JP5850221B2 - Image recording device - Google Patents

Description

  The present invention relates to an image recording apparatus that performs so-called borderless printing, in which a recording head ejects ink onto a recording medium and prints an image without providing a margin on the edge of the recording medium.

  2. Description of the Related Art Conventionally, there is an image recording apparatus capable of so-called borderless printing, in which an image is printed without providing a margin at the edge of a recording medium. When performing borderless printing with this image recording apparatus, the recording head ejects ink beyond the recording medium to the outside of the recording medium. For example, an area setting unit that sets an area for ejecting ink generates an ink ejection area larger than the size in the width direction orthogonal to the conveyance direction of the recording medium. The recording head ejects ink according to the ink ejection area set by the area setting means, thereby realizing borderless printing. When borderless printing is realized, ink that protrudes from the recording medium is ejected onto a platen that faces the ink ejection surface of the recording head and supports the recording medium from below when the ink is ejected.

  As an example of an image recording apparatus capable of borderless printing, there is a recording apparatus described in Patent Document 1. A recording apparatus described in Patent Document 1 includes a carriage that mounts an inkjet recording head and scans in a main scanning direction, a conveyance roller that conveys a recording medium in a conveyance direction, and a downstream roller that is disposed on the upstream side of the carriage conveyance direction. And a paper width sensor that detects the position of the end portion in the main scanning direction of the recording medium that is mounted on the carriage and conveyed.

  When performing borderless printing with the recording apparatus described in Patent Document 1, first, the carriage is moved in the main scanning direction, and the position of the end of the recording medium in the main scanning direction is detected by a paper width sensor. The detected positions of both ends of the recording medium in the main scanning direction are stored, and a protruding area is set from each of the stored positions of the both ends in a direction in which no recording medium exists in the main scanning direction. Then, the recording head ejects ink over the set protruding area and the area in the main scanning direction of the recording medium. After that, the recording medium is conveyed by a predetermined amount, and borderless printing is performed on the entire surface of the recording medium by repeating the detection of the end portion in the main scanning direction, the setting of the protruding area, and the ejection of the ink.

JP 2006-168110 A

  As described above, borderless printing sets the ink ejection area more than the width orthogonal to the conveyance direction of the recording medium. This ink discharge area is composed of a width area of the recording medium and a protruding area that protrudes from the width. Therefore, the ink ejected in the protruding area lands on the platen facing the recording head.

  Here, the platen has a plurality of protrusions extending in parallel to the transport direction. The plurality of protrusions are arranged on the platen at a predetermined distance along the width direction of the recording medium in order to appropriately support recording media of various sizes. Therefore, the recording medium to be conveyed is supported by a plurality of protrusions provided in the platen.

  In the recording apparatus described in Patent Document 1, each time the recording medium is conveyed by a predetermined amount, the protruding area is set based on the detected end portion of the recording medium in the main scanning direction. No processing has been done for the times that are included. Therefore, when the recording head ejects ink according to the protruding area, if the protruding area includes a protruding portion, the protruding portion is contaminated by the ink. In this case, when an image is to be recorded on the subsequent recording medium, if the subsequent recording medium passes through the damaged projection, a show-through occurs in which ink adheres to the back side of the subsequent recording medium. There was a risk of it.

  An object of the present invention is to provide an image recording apparatus capable of reducing show-through to a subsequent recording medium even when a protruding portion of a platen is included in the protruding area.

  In order to achieve this object, an image recording apparatus according to claim 1 is provided with a transport unit that transports a recording medium in the transport direction, and a recording head that discharges ink to the transported recording medium. The recording head comprising: a carriage that can reciprocate in a perpendicular main scanning direction; and a plurality of protrusions that support a lower surface of a recording medium to be conveyed and extend in the sub-scanning direction and are arranged in the main scanning direction. A platen disposed at a position opposite to the lower surface of the recording medium, and a recording medium to be conveyed or an optical unit that emits light to the platen and receives reflected light, and is received by the optical unit Both end determination means for determining the first end positions in the main scanning direction of the recording medium conveyed from the light, the region between the determined first end positions, and one end of the first end positions In the scanning direction A region on one side extending to the outside of the recording medium and a region on the other side extending from the other end of the first end positions to the outside of the recording medium in the main scanning direction. A discharge area setting means for setting; a control means for controlling the recording head and the carriage so as to discharge ink in an area for discharging ink set by the discharge area setting means; and one of the first end positions. A first area setting means for setting a first area extending from the edge to the outside of the recording medium in the main scanning direction by a first distance; and a recording medium in the main scanning direction from the other end of the first both end positions. A second area setting means for setting a second area extending outside by a second distance, extending from one end of the first both end positions to the outside of the recording medium in the main scanning direction, and the first area Distance A third area setting means for setting a third area within a third distance to a projection that is smaller than and located on the outer side of the recording medium and closest to the one end; and the other of the first end positions Within the fourth distance from the end to the outside of the recording medium in the main scanning direction and smaller than the second distance and located outside the recording medium and closest to the other end A fourth area setting means for setting a fourth area; a first determination means for determining whether or not the protrusion is in the first area at one end of the first both end positions; and the first both ends An image recording apparatus comprising: a second determination unit configured to determine whether or not the protrusion is in the first region at the other end of the position, wherein the discharge region setting unit includes the first both ends When it is determined that the protrusion is not in the first region at one end of the position, The region used for the one side region is set as the first region, and when it is determined that the protrusion is in the first region at one end of the first both end positions, The region used for the region is set as the third region, and when it is determined that the protrusion is not present in the second region at the other end of the first both end positions, the region is used for the other region. When the region is set as the second region, and it is determined that the protrusion is in the second region at the other end of the first both end positions, the region used as the other region is the first region. It is characterized by setting to 4 areas.

  According to a second aspect of the present invention, in addition to the image recording apparatus according to the first aspect, the third area and the fourth area are recorded from one end and the other end of the first both end positions. And the third area setting means is not smaller than the third distance and the fourth distance, and has a size equal to or larger than a fifth area extending from the recording medium by a fifth distance corresponding to the resolution of the both end determination means. The third area is set at the maximum distance for each of the fifth distances, and the fourth area setting means sets the fourth area at the maximum distance for each of the fifth distances. And

According to a third aspect of the present invention, in addition to the second aspect of the image recording apparatus of the second aspect, the first storage unit capable of storing the first information and the first information stored in the first storage unit. Notification means for informing the case, third determination means for determining whether or not the protrusion is in the fifth region at the one end of the first end position, and the other end of the first end position And a fourth determination means for determining whether or not the protrusion is present in the fifth area at the end, wherein the discharge area setting means is provided in the first area at one end of the first both end positions. Is used for the region on the one side when it is determined that there is no projection in the fifth region at one end of the first end position. The region to be formed is set as the third region, and the protrusion is in the fifth region at one end of the first both end positions. When it is determined that there is a portion, the region used for the one side region is set as the first region, and the protrusion is in the second region at the other end of the first both end positions. If it is determined that it is determined that there is no projection in the fifth region at the other end of the first both end positions, the region used for the other region is the fourth region. And when it is determined that the protrusion is in the fifth region at the other end of the first both end positions, the region used for the other region is set as the second region, The first storage means stores the first information when it is determined that there is a protrusion in the fifth region at one end or the other end of the first both end positions. It is characterized by that.

  According to a fourth aspect of the present invention, in addition to the image recording apparatus according to any one of the first to third aspects, the both-end determining means conveys the recording medium by a predetermined amount that is larger than a single conveyance amount. The first end positions are determined every time, and the first end positions of the recording medium determined this time by the both end determination means and the second end positions of the recording medium determined last time are determined this time. A calculating unit that calculates a third both-end position of the recording medium at a position where the one conveyance amount is conveyed in the conveying direction from the position of the recording medium, and the ejection area setting unit calculates the calculated area A region between the third end positions, a region extending from one end of the third end positions to the outside of the recording medium in the main scanning direction, and a main scanning direction from the other end of the third end positions At the other side extending to the outside of the recording medium. And a sixth area that sets a sixth area extending from the one end of the third both end positions to the outside of the recording medium in the main scanning direction by the first distance. Setting means; seventh area setting means for setting a seventh area extending by the second distance from the other end of the third end positions to the outside of the recording medium in the main scanning direction; and the third end positions Extending from the one end of the recording medium to the outside of the recording medium in the main scanning direction, and from the first distance to the protrusion that is smaller than the first distance and is located outside the recording medium and closest to the one end. An eighth area setting means for setting the eighth area within three distances, and extends from the other end of the third both end positions to the outside of the recording medium in the main scanning direction, and is smaller than the second distance and The other side located outside the recording medium Whether the ninth region setting means for setting the ninth region within the fourth distance to the protrusion nearest to the end is different from the first end position and the second end position or the third end position And when the fifth determination means and the fifth determination means determine that the first end position is different from the second end position or the third end position, the third end position A sixth determination means for determining whether or not the protrusion is in the sixth region of the region on one side of the position, and the fifth determination means to determine whether the first both-end position and the second both-end position or A seventh determining means for determining whether or not the protrusion is in the seventh region of the region on the other side of the third end position when it is determined that the third end position is different from the third end position; The discharge area setting means further includes an area on one side of the third end positions. When it is determined that there is no protrusion in the sixth region, the region used for the one side region is set as the sixth region, and the sixth region in the one side region of the third both end positions is set. When it is determined that the protrusion is present in the region, the region used for the one side region is set as the eighth region, and the region on the other side of the third end positions is within the seventh region. When it is determined that there is no protrusion, an area used for the other area is set as the seventh area, and the protrusion is within the seventh area of the other area at the third end positions. When it is determined that there is, the area used for the other side area is set as the ninth area.

  According to a fifth aspect of the present invention, in addition to the image recording apparatus according to the fourth aspect, the eighth area and the ninth area are recorded from one end and the other end of the third both end positions. , The third distance and the fourth distance or less, and a size equal to or larger than the tenth area extending from the recording medium to the fifth distance corresponding to the resolution of the both end determination means, and the eighth area. The setting means sets the eighth area at the maximum distance for each fifth distance, and the ninth area setting means sets the ninth area at the maximum distance for each fifth distance. It is characterized by.

  In addition to the image recording apparatus according to claim 5, the image recording apparatus according to claim 6 is a second storage unit capable of storing the first information, and the tenth region at one end of the third both end positions. And an eighth determination means for determining whether or not the protrusion is in the tenth area, and a ninth determination means for determining whether or not the protrusion is in the tenth region at the other end of the third end positions. And the discharge region setting means determines that the protrusion is in the sixth region of the region on one side of the third end positions, and the discharge region setting means When it is determined that the protrusion is not present in the tenth region at one end, the region used for the one region is set as the eighth region, and one end of the third end position is set. When it is determined that the protrusion is in the tenth region, it is used for the one side region. When the region is set to the sixth region and it is determined that the protrusion is in the seventh region of the region on the other side of the third end position, the other end of the third end position When it is determined that there is no protrusion in the tenth region, the region used for the other region is set as the ninth region, and the tenth portion at the other end of the third end positions is set. When it is determined that the protrusion is present in the region, the region used for the other side region is set as the seventh region, and the second storage means is configured to either one end of the third both end positions or When it is determined that there is a protrusion in the tenth region at the other end, the first information is stored, and the notification unit stores the first information in the second storage unit. In this case, it is notified.

  In addition to the image recording device according to any one of claims 3 and 6, an image recording device according to claim 7 includes a cover that covers the platen and can be opened and closed, and a detection unit that detects opening and closing of the cover. The notifying means starts notifying when printing of one page of the recording medium is completed, and stops notifying on the condition that the opening / closing of the cover is detected by the detecting means.

  According to the image recording apparatus of the first aspect, when it is determined that there is a protrusion in the first region at one end of the first both end positions determined by the first determination unit, the ejection region setting unit The area used for the side area is set to a third area that is set within a third distance to the protrusion that is located outside the recording medium and is closest to one end. In addition, when it is determined that there is a protrusion in the second region at the other end of the first both end positions determined by the second determination unit, the discharge region setting unit determines the region used as the other region to be covered. It is set in a fourth area that is set within a fourth distance to the protrusion that is located outside the recording medium and is most adjacent to the other end.

  The control unit controls the carriage and the print head according to the third area for one end and according to the fourth area for the other end. As a result, it is possible to reduce the adhesion of ink to the protrusion, and even if the subsequent recording medium is conveyed, the show-through to the subsequent recording medium can be reduced.

  According to another aspect of the image recording apparatus of the present invention, the third area setting means sets the third area at the maximum distance of the fifth distance corresponding to the resolution of the both end detection means, and the fourth area setting means. Sets the fourth region by the maximum distance of the fifth distance corresponding to the resolution of the both end detection means. Therefore, according to the image recording apparatus of the second aspect, in addition to the effect exhibited by the image recording apparatus of the first aspect, the image quality of borderless printing can be ensured, and further, the ink adheres to the protrusion. Since it can be reduced, even if the subsequent recording medium is conveyed, there is an effect that the show-through to the subsequent recording medium can be reduced.

  According to the image recording apparatus of the third aspect, when the third determining means determines that there is a projection in the fifth area at one end of the recording medium, or the fourth determining means If it is determined that there is a protrusion in the fifth region at the other end of the medium, the first information is stored in the storage means. Then, the notification unit performs notification on the condition that the first information is stored in the storage unit.

  Thereby, according to the image recording apparatus of claim 3, in addition to the effect produced by the image recording apparatus of claim 2, there is a protrusion in the fifth region, that is, the protrusion is soiled by ink. Since the notification is made even if it is closed, there is an effect that the user can confirm that the protruding portion is soiled and can give an opportunity to clean the protruding portion.

  According to the image recording apparatus of the fourth aspect of the present invention, it is determined this time from the first end positions of the recording medium determined this time by the both end determination means and the second end positions of the recording medium determined last time. From the position of the recording medium, the third end positions of the recording medium at the position where the transport amount of one time is transported in the transport direction are calculated. When the first end position is different from the second end position or the third end position, the ejection region setting means has projections in the sixth region and the seventh region at the third end position. Determine whether or not. When the first end position is different from the second end position or the third end position, that is, the recording medium is transported while being skewed, both ends of the recording medium are transported each time the recording medium is transported. Even when the position changes and the position of the sixth area or the seventh area changes, after the determination of the both end positions this time, the first end of the recording medium at the both end positions after one transport is determined. The sixth area or the eighth area and the seventh area or the ninth area can be set for the other end of the recording medium.

  Therefore, in addition to the effects achieved by the image recording device according to any one of claims 1 to 3, the image recording device according to claim 4 can be performed once even if the recording medium is conveyed in a skewed state. Since each region can be set at both end positions after the conveyance, it is possible to further reduce the adhesion of ink to the protrusions and to reduce the show-through to the subsequent recording medium.

  According to the image recording apparatus of the fifth aspect, the eighth area setting means sets the eighth area at the maximum distance of the fifth distance corresponding to the resolution of the both end detection means, and the ninth area setting means. Sets the ninth region by the maximum distance of the fifth distance corresponding to the resolution of the both end detection means. Therefore, according to the image recording apparatus of the fifth aspect, in addition to the effect produced by the image recording apparatus of the fourth aspect, it is possible to guarantee the image quality of borderless printing and further, the ink adheres to the protrusion. Since it can be reduced, even if the subsequent recording medium is conveyed, there is an effect that the show-through to the subsequent recording medium can be reduced.

  According to the image recording apparatus of the sixth aspect, when the eighth judging means judges that there is a protrusion in the tenth region at one end of the recording medium, or the ninth judging means If it is determined that there is a protrusion in the tenth region at the other end of the medium, the first information is stored in the second storage means. Then, the notifying means notifies on the condition that the first information is stored in the second storage means.

  Thus, according to the image recording apparatus of the sixth aspect, in addition to the effect exhibited by the image recording apparatus of the fifth aspect, there is a protrusion in the tenth region, that is, the protrusion is soiled by ink. Since the notification is made even if it is closed, there is an effect that the user can confirm that the protruding portion is soiled and can give an opportunity to clean the protruding portion.

  According to the image recording apparatus of the seventh aspect, the notification is started when printing of one page of the recording medium is completed, and the notification is stopped when the opening / closing of the cover is detected. Thereby, according to the image recording apparatus of Claim 7, in addition to the effect which the image recording apparatus of any one of Claim 3 or 6 show | played, the user damaged the protrusion part via the alerting | reporting part. In addition, since the notification is continued until the cover is opened and closed, the ink ejected to the protrusion can be cleaned, and the show-through to the subsequent paper can be reduced. be able to.

1 is a perspective view of a multifunction machine 10. 2 is a schematic cross-sectional view of a printer unit 11. FIG. 3 is a perspective view of a paper feed tray 20. FIG. 3 is a top view of the printer unit 11. FIG. FIG. 6 is a perspective view showing the periphery of a recording unit 24. 3 is a top view showing the periphery of the platen 34. FIG. FIG. 6 is a schematic diagram illustrating detection of both side edges of the paper P by the media sensor 52. 3 is a block diagram illustrating a configuration of a control unit 90. FIG. It is a flowchart which shows the borderless printing process of this embodiment. It is a flowchart which shows the protrusion area | region setting process before printing of this embodiment. It is a flowchart which shows the printing process of this embodiment. It is a flowchart which shows the protrusion area | region setting process in printing of this embodiment. It is a flowchart which shows the protrusion area | region setting process in printing of this embodiment. FIG. 6 is a diagram illustrating the relative positions of the paper P, the ribs 81, and the protruding area when borderless printing is performed on the paper P that is not skewed. FIG. 10 is a diagram illustrating the relative positions of the paper P2, the rib 81, and the protruding area when borderless printing is performed on the skewed paper P2.

  Hereinafter, embodiments of the present invention will be described. The embodiment described below is merely an example of the present invention, and it is needless to say that the embodiment of the present invention can be changed as appropriate without departing from the gist of the present invention. Further, in the following description, the progression from the start point to the end point in consideration of the arrow in the vector is expressed as “direction”, and the traffic on the line connecting the start point and the end point without considering the arrow in the vector is referred to as “direction”. Expressed. In the following description, the vertical direction 7 is defined with reference to the state in which the multifunction machine 10 is installed (the state in FIG. 1), and the side where the opening 13 is provided is the front side (front side). A direction 8 is defined, and a left-right direction 9 is defined when the multifunction machine 10 is viewed from the front side (front).

<Appearance of MFP 10>
With reference to FIG. 1, an appearance of a multifunction machine 10 including an embodiment of the present invention will be described. As shown in FIG. 1, a multifunction machine 10, which is an example of an ink jet recording apparatus of the present invention, is formed in a generally thin rectangular parallelepiped. An ink jet recording type printer unit 11 is provided in the lower part of the multifunction machine 10. The multifunction machine 10 has various functions such as a facsimile function and a print function.

  The printer unit 11 has a housing 14. A front wall 15 extending in the vertical direction 7 and the horizontal direction 9 is formed on the front side of the housing 14. An opening 13 is formed at a substantially central portion of the front wall 15. The paper feed tray 20 and the paper discharge tray 21 can be inserted and removed from the opening 13 in the front-rear direction. A sheet P having a desired size is placed on the sheet feeding tray 20. A display unit 18 is disposed above the front wall 15, and the display unit 18 displays the state of the multifunction machine 10.

  The multifunction machine 10 is provided with a cover 12 (an example of the cover of the present invention) on the top of the housing 14. The cover 12 is pivotally supported at the rear end portion of the multifunction machine 10 so as to be rotatable in the vertical direction 7, and is configured so that the user can open and close the cover 12. In addition, the multifunction machine 10 is provided with an open / close sensor 19 (see FIG. 8, an example of the detection means of the present invention) that detects the opening / closing of the cover 12. The user can access the printer unit 11 by rotating the cover 12 upward and opening the cover 12, and can clean the inside of the printer unit 11, for example, the paper P in which a paper jam has occurred. It can be removed. Further, the cover 12 covers at least a platen 34 described later in the closed posture.

  The multifunction device 10 can be connected to an external device such as a personal computer (hereinafter referred to as a PC), and various functions of the multifunction device 10 are executed by the PC. The multifunction machine 10 executes various functions only with the multifunction machine 10 main body. In this case, when the user operates the operation panel 16 provided with the display unit 18 (an example of the notification unit of the present invention) above the front wall 15, the multifunction device 10 can perform various functions only by the multifunction device 10 main body. Run.

<Internal structure of printer unit 11>
Next, the internal structure of the printer unit 11 will be described with reference to FIGS. As shown in FIG. 2, the printer unit 11 feeds the paper P placed on the paper feed tray 20 to the transport path 23, and the paper P fed by the feeding unit 17. A pair of transport rollers 54 transported to the recording section 24, a recording section 24 of an ink jet recording system that records an image on the paper P transported by the pair of transport rollers 54, and the paper P recorded by the recording section 24 is discharged to the discharge tray 21. A pair of paper discharge rollers 55 for discharging paper is provided.

<Feeding unit 17>
As shown in FIG. 2, a feeding unit 17 is provided on the upper side of the paper feed tray 20. The feeding unit 17 includes a paper feeding roller 25, a paper feeding arm 26, and a drive transmission mechanism 27. The paper feed roller 25 is pivotally supported at the end of a paper feed arm 26 that moves up and down detachably from the paper feed tray 20. The paper feed roller 25 is rotated by a driving force of a paper feed motor 76 (see FIG. 8) transmitted by a drive transmission mechanism 27 in which a plurality of gears are engaged. The paper feed roller 25 is pressed against the paper P on the paper feed tray 20 and rotates in that state. As a result, the stacked paper P is fed to the conveyance path 23 described below.

<Paper Tray 20>
Hereinafter, the sheet feeding tray 20 will be described with reference to FIGS. 2 and 3. The paper feed tray 20 includes a placement plate 22 on which the paper P is placed, a pair of guide plates 101 provided on both sides of the placement plate 22 in the left-right direction 9, a rotatable gear 102, and left and right from the guide plate 101. A cam portion 103 having a cam that extends in the direction 9 and meshes with the gear 102 and a paper discharge tray 21 are provided. The guide plate 101 is prepared as a pair on both sides in the left-right direction 9 on the mounting plate 22 and is provided in a state of standing upward. The gear 102 is disposed at the central portion in the left-right direction 9 of the mounting plate 22. Further, the guide plate 101 is provided with cam portions 103 extending in the left-right direction 9, and each cam portion 103 is provided with comb-like teeth so as to mesh with the gear 102.

  When the pair of guide plates 101 is operated in the left-right direction 9 by the user, the comb-shaped teeth of the pair of cam portions 103 move and the gear 102 rotates. As a result of the movement of the pair of cam portions 103 and the rotation of the gear 102, the distance between the pair of guide plates 101 increases along the left-right direction 9 with respect to the center of the left-right direction 9. It gets smaller. Accordingly, by operating the pair of guide plates 101 according to the size of the paper P in the left-right direction 9, the paper P on which an image is recorded is set at the center position.

  A paper discharge tray 21 is disposed above the front side of the paper feed tray 20. The paper discharge tray 21 receives the paper P recorded by the recording unit 24.

<Conveyance path 23>
As shown in FIG. 2, the conveyance path 23 is bent upward from the rear end of the paper feed tray 20 and to the front side of the printer unit 11, and from the back side (rear side) to the front side (front side) of the printer unit 11. ). Further, the conveyance path 23 passes through the nipping position by the conveyance roller pair 54, the lower side of the recording unit 24, and the nipping position by the paper discharge roller pair 55 and communicates with the paper discharge tray 21. The paper P fed from the paper feed tray 20 is guided to make a U-turn from the lower side to the upper side by the transport path 23 and reaches the recording unit 24. The paper P is ejected to the paper ejection tray 21 after image recording is performed by the recording unit 24. The conveyance path 23 is formed by an outer guide member 29 and an inner guide member 28 that are opposed to each other at a predetermined interval except for a place where the recording unit 24 and the like are disposed.

<Conveying roller pair 54 and paper discharge roller pair 55>
Hereinafter, the direction in which the paper P is transported along the transport path 23 (the direction indicated by the dashed arrow in FIG. 2) will be described as the transport direction 5.

  As shown in FIG. 2, upstream of the recording unit 24 in the transport direction 5, a transport roller 47 disposed above the transport path 23 and a pinch disposed below the transport path 23. A conveying roller pair 54 (an example of the conveying means of the present invention) having a roller 48 is provided. A discharge roller having a discharge roller 49 disposed below the conveyance path 23 and a spur 50 disposed above the conveyance path 23 on the downstream side in the conveyance direction 5 with respect to the recording unit 24. A pair 55 (an example of the conveying means of the present invention) is provided. A paper discharge tray 21 is arranged downstream of the paper discharge roller pair 55 in the transport direction 5. That is, the paper discharge tray 21 is provided on the downstream side in the transport direction 5 with respect to the recording unit 24. Further, the paper discharge roller pair 55 is provided between the recording unit 24 and the paper discharge tray 21 in the transport path 23.

  As shown in FIG. 5, the transport roller 47 is rotationally driven by a driving force transmitted from a transport motor 59 connected to one end of the transport roller 47 in the left-right direction 9. The paper discharge roller 49 is driven to rotate by the conveying roller 47 via the intermediate gear 57 and the belt 58 and is driven to rotate. Therefore, the rotational drive of the paper discharge roller 49 depends on the rotational drive of the transport roller 47.

  Then, when the transport roller 47 is driven to rotate forward (counterclockwise in FIG. 2), the paper P fed from the paper feed tray 20 is nipped by the transport roller pair 54 and is transported in the transport direction 5. It is conveyed to. When the paper discharge roller 49 is driven forward (driven clockwise in FIG. 2), the paper P on which an image has been recorded by the recording unit 24 is nipped by the paper discharge roller pair 55 and transported in the transport direction 5. Is done. That is, the paper P is discharged to the paper discharge tray 21 by the paper discharge roller pair 55.

<Rotary encoder 68>
As shown in FIGS. 2 and 5, a rotary encoder 68 that detects the amount of rotation of the transport roller 47 is provided on one end side of the transport roller 47. The rotary encoder 68 includes an encoder disk 51 and an optical sensor 60 which are provided coaxially with the transport roller 47 and rotate together with the transport roller 47. The encoder disk 51 is formed with a pattern in which transmissive portions that transmit light at regular intervals and non-transmissive portions that do not transmit light are alternately arranged at equal pitches in the circumferential direction. When the encoder disk 51 rotates together with the transport roller 47, a pulse signal is generated each time the pattern of the encoder disk 51 is detected by the optical sensor 60. The pulse signal is output to the control unit 90 (see FIG. 8). The rotary encoder 68 detects the rotation amount of the transport roller 47, and the rotational drive of the transport roller 47 and the paper discharge roller 49 is controlled according to the detection result.

<Recording unit 24>
As shown in FIG. 2, the recording unit 24 records an image on the paper P by a so-called ink jet method in the present embodiment, and has a recording head 30 mounted on the lower side in the main scanning direction (in FIG. 2). A carriage 31 (an example of a carriage according to the present invention) is provided that reciprocates in a direction perpendicular to the paper surface, that is, the left-right direction 9). Further, a platen 34 that supports the paper P conveyed by the conveyance roller pair 54 is provided below the recording head 30.

  As shown in FIG. 4, cyan (C), magenta (M), yellow (Y), and black (K) inks are supplied to the recording head 30 from the ink tank 46 through the ink tube 33. The ink tank 46 has a cyan cartridge 32C filled with cyan ink, a magenta ink cartridge 32M filled with magenta ink, a yellow cartridge 32Y filled with yellow ink, and a black color. Each color ink cartridge 32 such as a black cartridge 32 </ b> K filled with each ink is mounted, and ink is supplied from each color ink cartridge 32 to the ink tank 46.

  As shown in FIG. 2, a plurality of nozzles 310 corresponding to the inks of the respective colors are formed on the lower surface of the recording head 30. The one-color nozzles 310 are arranged in a line along the front-rear direction 8, and the line along the front-rear direction 8 of the one-color nozzle 310 corresponds to the main scanning direction of the carriage 31 (see FIG. 2) so as to correspond to each color ink. They are arranged in a direction perpendicular to the plane of the paper, that is, in the left-right direction 9).

  The recording head 30 ejects ink of each color as minute ink droplets from a nozzle 310 provided on the lower surface thereof. Then, when the carriage 31 reciprocates in the left-right direction 9, the recording head 30 is scanned with respect to the paper P, and an image is recorded on the paper P conveyed on the platen 34.

  As shown in FIGS. 4 and 5, a pair of guide rails 35, 36 on a flat plate are arranged in the recording unit 24 at a predetermined interval in the front-rear direction 8, and the pair of guide rails 35, 36 extends along the left-right direction 9. The carriage 31 is reciprocated by sliding on the guide rails 35, 36 across the pair of guide rails 35, 36.

  As shown in FIG. 4, a belt drive mechanism 38 is disposed on the upper surface of the guide rail 36. The belt drive mechanism 38 includes a drive pulley 39 provided at one end of the guide rail 36 in the left-right direction 9, a driven pulley 40 provided at the other end, and the pulleys 39, 40 stretched and teeth on the inside. An endless annular timing belt 41. A driving force is input from the carriage motor 73 (see FIG. 8) to the shaft of the driving pulley 39, and the timing belt 41 moves circumferentially by the rotation of the driving pulley 39. The timing belt 41 is fixed to the carriage 31. Therefore, the reciprocating movement of the carriage 31 is realized by the circumferential movement of the timing belt 41.

<Linear encoder 69>
As shown in FIGS. 4 and 5, an encoder strip 42 is disposed on the guide rail 36, and a transmissive portion that transmits light at a constant interval in the left-right direction 9 and a non-transmissive portion that does not transmit light are equal. Patterns arranged alternately at a pitch are formed. An optical sensor (not shown) provided in the carriage 31 detects the pattern of the encoder strip 42 by irradiating the pattern formed on the encoder strip 42 with light. Each time a pattern is detected, a pulse signal is generated. The pulse signal is output to the control unit 90 (see FIG. 8). The encoder strip 42 and a linear encoder 69 comprising an optical sensor (not shown) provided in the carriage 31 detect the position in the left-right direction 9 when the carriage 31 reciprocates, and the main scanning direction of the carriage 31 is detected according to the detection result. Movement is controlled. The control unit 90 detects and determines the position of the carriage 31 in the main scanning direction using the count value counted by the linear encoder 69.

  The specific resolution of the linear encoder 69 of the multifunction machine 10 of this embodiment is 150 dpi, which is 0.17 mm. Needless to say, the resolution of the linear encoder 69 may be set larger than 150 dpi or smaller.

<Platen 34>
As shown in FIGS. 2 and 4 to 7, a platen 34 (an example of a platen of the present invention) is disposed below the recording head 30 (in FIG. 4, the direction perpendicular to the paper surface). Further, the platen 34 is disposed in a portion where the transported paper P can pass through the reciprocating range of the carriage 31, and the size of the platen 34 in the left-right direction 9 can be placed on the paper feed tray 20. It is larger than the maximum width of the largest sheet P, and both ends of the conveyed sheet P pass over the platen 34.

  Hereinafter, the platen 34 will be described with reference to FIG. The platen 34 is provided with a non-ejection portion 80 where ink is not ejected in the front-rear direction 8 and an ejection target portion 85 facing the lower side of the plurality of nozzles 310 (in the direction perpendicular to the paper surface in FIG. 6). And a rib 81 (an example of the protrusion of the present invention) provided so as to extend the portion 80 and the discharged portion 85 along the front-rear direction 8.

  The non-ejecting portion 80 includes a horizontal plane portion 82 and an inclined surface 83 that is inclined so as to be spaced downward (in the direction perpendicular to the plane of FIG. 6) from the nozzle 310 as it goes forward in the front-rear direction 8. . A media sensor 52 (see a dotted line in FIG. 6) provided on the carriage 31 is disposed immediately above the inclined surface 83. When the media sensor 52 passes immediately above the inclined surface 83, the light emitted by the light emitting element is irregularly reflected. As a result, the amount of light received by the sheet P conveyed on the platen 34 and the platen 34 becomes clearer and different, and the positions of both ends of the sheet P can be accurately detected. The detection of the paper P by the media sensor 52 will be described later.

  The upper surface of the rib 81 is closest to the nozzle 310 in the platen 34. Therefore, the lower surface of the paper P conveyed to the platen 34 is supported by the ribs 81. A plurality of ribs 81 are provided along the front-rear direction 8 and are provided at predetermined intervals along the left-right direction 9.

  Further, the ribs 81 are provided such that the distance from the center line C (see the dashed line in FIG. 6) in the left-right direction 9 of the platen 34 to the left side and the right side is equal. For example, the rib 81A and the rib 81B are provided such that the distance from the center line C in the left-right direction 9 to the left side and the right side is X (mm) (see the two-dot chain line in FIG. 6). In the center line C, the intervals between the ribs 81 facing each other at equal intervals in the left-right direction 9 are set to be smaller than the width in the left-right direction 9 of the standard paper to be conveyed. For example, the interval 2X between the rib 81A and the rib 81B is an interval smaller than the width in the left-right direction 9 of the A4 sheet that is a standard sheet (see the two-dot chain line in FIG. 6).

  Specifically, the interval 2X between the rib 81A and the rib 81B is 5.2 mm smaller than the width in the left-right direction 9 of the A4 paper that is a standard paper. Accordingly, the distance from the rib 81A to the left end of the A4 sheet and the distance from the rib 81B to the right end of the A4 sheet are set to 2.6 mm. In the multi-function device 10 of this embodiment, the error in the left-right direction 9 of the paper P fed by the feeding unit 17 is ± 1.8 mm, and the paper P in the left-right direction 9 is 1.8 mm, which is the maximum error. Even if they are shifted, the rib 81A and the rib 81B can support the A4 paper. These specific distances are arbitrary, and the rib 81A and the rib 81B can support the A4 sheet with respect to the error in the left-right direction 9 of the A4 sheet fed by the feeding unit 17. The range can be changed as appropriate.

  Further, the position of each rib 81 in the left-right direction 9 and the position of the center line C in the left-right direction 9 of the platen 34 are stored in advance in the ROM 92 (see FIG. 8) in the control unit 90. And stored as a count value counted by the linear encoder 69.

  The ejected portion 85 merges with the flat portion 86, a plurality of inclined grooves 87 that incline downward (in the direction perpendicular to the paper surface in FIG. 6) toward the front side, and front end portions of the plurality of inclined grooves 87, And a lateral groove 88 extending substantially over the entire area of the discharged portion 85 in the left-right direction 9. Further, an unillustrated absorber that absorbs ink droplets is disposed below the ejected portion 85 (in the direction perpendicular to the paper surface in FIG. 6), and the lateral groove 88 is disposed below (as shown in FIG. 6) so as to be connected to the absorber. 6 in the direction perpendicular to the paper surface). The inclined grooves 87 extend along the front-rear direction 8 and are provided with a predetermined distance along the left-right direction 9.

  When ink droplets are ejected onto the ejected portion 85, first, the ink droplets land on the flat portion 86 or the inclined groove 87. The ink droplets that have landed on the flat surface portion 86 are moved to the inclined groove 87. The ink droplets landed or moved in the inclined groove 87 are moved to the lateral groove 88 that merges with the front end portion of the inclined groove 87 according to the inclination of the inclined groove 87. Since the horizontal groove 88 passes through the absorbent body 85 so as to be connected to the absorber disposed in the lower side (perpendicular to the paper surface in FIG. 6), the ink droplets moved to the horizontal groove 88 pass through the horizontal groove 88. Passes and is absorbed by the absorber. In this way, the ink droplets ejected to the ejected portion 85 of the platen 34 are absorbed by the absorber without remaining in the flat portion 86, the inclined groove 87, and the lateral groove 88.

<Media sensor 52>
As shown in FIGS. 2 and 4, on the rear side of the carriage 31, there is a media sensor 52 (the optical means of the present invention) that can detect the presence / absence of the sheet P being conveyed and the positions of both ends of the sheet P in the left-right direction 9 Example). The media sensor 52 includes a light emitting element such as a light emitting diode and a light receiving element such as a phototransistor. The light emitted from the light emitting element is applied to the recording medium conveyed on the platen 34, and is irradiated to the platen 34 when the recording medium is not conveyed up to the platen 34. And the light irradiated to the paper P or the platen 34 is reflected, the light receiving element receives the reflected light, and outputs according to the amount of received light. As a result, it is possible to detect whether the paper P is present at a position facing the media sensor 52, and the positions of both side edges 9 in the left-right direction 9 of the paper P when the paper P is facing the media sensor 52.

  Next, detection of both end positions in the left-right direction 9 of the paper P by the media sensor 52 will be described with reference to FIG. In FIG. 7, the conveyance roller pair 54 and the discharge roller pair 55 are omitted for the sake of simplicity.

  As shown in FIG. 7, in the front-rear direction 8, the media sensor 52 is disposed so as to face the inclined surface 83 on the lower side (perpendicular to the paper surface in FIG. 7). When the paper P is transported to a position facing the lower side of the media sensor 52, the light emitting element of the media sensor 52 emits light toward the inclined surface 83 or the paper P while the carriage 31 moves from the position A1 to the position A2. , The light receiving element of the media sensor 52 receives the reflected light from the upper surface of the platen 34 and the paper P. Here, by setting the upper surface of the platen 34 to a color having a low reflectance such as black, the amount of light received by the light receiving element by the reflected light of the paper P and the amount of light received by the light receiving element by the reflected light from the upper surface of the platen 34 However, each amount is different.

  When the carriage 31 is moved and the media sensor 52 passes the one end T1 of the paper P, the amount of light received by the media sensor 52 varies from the amount of light reflected from the platen 34 to the amount of light reflected from the paper P. To do. When the carriage 31 is further moved and the media sensor 52 passes the other end T2 of the paper P, the amount of light received by the media sensor 52 changes from the amount of light reflected from the paper P to the amount of light reflected from the platen 34. fluctuate.

  Here, since the position in the left-right direction 9 when the carriage 31 reciprocates is detected by the linear encoder 69, the position where the amount of received light fluctuates is made to correspond to the position of the carriage 31 detected by the linear encoder 69. The position of the paper P conveyed on the platen 34 is detected. As described above, the positions of the both ends of the paper P are detected by the variation in the amount of light received by the light receiving element of the media sensor 52. In addition, when determining the both end positions of the paper P, the count value counted by the linear encoder 69 is used. Further, for example, only the position of the left end or right end of the paper P is determined by the count value, and then the position of the left end or right end of the paper P is determined from the position of the left end or right end of the paper P determined previously. It may be determined after calculating by increasing or decreasing the length in the left-right direction 9.

<Sheet Detection Unit 110>
As shown in FIG. 2, the printer unit 11 includes a sheet detection unit 110 that detects the paper P conveyed through the conveyance path 23. The sheet detection unit 110 is provided on the upstream side in the transport direction 5 with respect to the transport roller pair 54 in the transport path 23. The sheet detection unit 110 includes, for example, a photo interrupter including a rotating body 112 having detectors 112A and 112B, a light emitting element (for example, a light emitting diode), and a light receiving element (for example, a phototransistor) that receives light emitted from the light emitting element. And the like optical sensor 111. The rotating body 112 is provided so as to be rotatable about the support shaft 113. The detector 112 </ b> A protrudes from the support shaft 113 into the conveyance path 23. In a state where no external force is applied to the rotator 112, the detector 112B enters the optical path from the light emitting element to the light receiving element of the optical sensor 111 and blocks light passing through the optical path. When the rotating body 112 is rotated by being pushed by the leading edge of the paper P, the detector 112B is removed from the optical path, and light passes through the optical path.

<Electrical configuration>
Next, the electrical configuration of the multifunction machine 10 will be described with reference to FIG. FIG. 8 is a block diagram illustrating an electrical configuration of the control unit 90 of the multifunction machine 10. The control unit 90 controls the overall operation of the multifunction machine 10, but a detailed description of the control of the scanner unit 12 and the recording unit 24 is omitted.

  As shown in FIG. 8, the control unit 90 is connected to the ASIC 98 via the bus 95. Connected to the ASIC 98 are various parts, specifically, a drive circuit 96 that drives the motors 71, 73, and 75, a rotary encoder 68, a linear encoder 69, and a media sensor 52. The drive circuit 96 includes drivers for driving the paper feed motor 71, the carriage motor 73, and the transport motor 75. The paper feed motor 71, the carriage motor 73, and the transport motor are provided. 75 is independently controlled by each driver. The control unit 90 drives the drive circuit 96 via the ASIC 98 and controls the operations of the rotary encoder 68, linear encoder 69, media sensor 52, and open / close sensor 19.

  The control unit 90 includes a CPU 91, ROM 92, RAM 93, and EEPROM 94. The CPU 91 controls various functions of the multifunction machine 10 and controls each unit connected to the ASIC 98 according to predetermined values and programs stored in the ROM 92 and the RAM 93.

  The ROM 92 stores a program for the CPU 91 to control various operations of the multifunction machine 10. The ROM 92 stores, for example, various control programs including programs for executing the processes shown in the flowcharts shown in FIGS. 9 to 13, data necessary for executing these various programs on the CPU 91, and the like. Yes.

  The RAM 93 is used as a storage area for temporarily storing various data used when the CPU 91 executes various programs. The RAM 93 includes a first side edge memory 93A, a second side edge memory 93B, a third side edge memory 93C, a first protrusion area memory 93D, a second protrusion area memory 93E, an image data memory 93F, and a dirt flag memory 93G. Various storage areas are allocated.

  The first both-side edge memory 93A is a storage area for storing the both-side edge positions in the left-right direction 9 currently determined by the media sensor 52 for the paper P. The second side end memory 93B is a storage area for storing the side end positions in the left-right direction 9 previously determined by the media sensor 52 for the paper P. When the both-side edge positions of the sheet P are stored in the second both-side edge memory 93B, if the current both-side edge positions of the sheet P are stored in the first both-side edge position memory 93A, the first both-side edge position memory until then is stored. The positions of the both ends of the sheet P stored in 93A are moved and stored in the second both ends memory 93B. The third side edge memory 93C includes the estimated side edge positions of the paper P calculated based on the both side edge positions of the paper P stored in the first side edge memory 93A and the second side edge memory 93B. Stores the estimated left and right side edge positions in the left-right direction 9 when the currently detected sheet P is transported by 0.1 inch (an example of the transport amount of the present invention) once by the transport means. . The both end positions are determined by the media sensor 52 every five times, that is, every 0.5 inch (an example of the predetermined amount of the present invention).

  Here, calculation of the estimated positions on both sides of the estimated paper P will be described. Assume that X1 is stored in the first both-end memory 93A and X2 is stored in the second both-end memory. X1 and X2 are the coordinates in the left-right direction 9 of the both side edge positions of the paper determined by the media sensor 52. Further, the both end positions are determined by the media sensor 52 when it is conveyed every 0.5 inch, and since one conveyance is 0.1 inch, the both end positions X1 and X2 of these sheets P are used. X3 stored in the third both-end memory is calculated as X1 + 0.2 × (X1-X2).

  In the first protruding area memory 93D and the second protruding area memory 93E, the margins of the sheet P are exceeded from both ends (that is, in the left-right direction 9) during borderless printing for recording an image without providing a margin at the edge of the sheet P. This is a storage area in which an area that protrudes outside the sheet is stored. Specifically, this protrusion area is, for example, an area from the ink discharge start position outside the paper P to one side edge of the paper, or a section from the ink discharge end position outside the paper P to the other side edge of the paper. These two areas are stored as encoder count values of the linear encoder 69.

  The protruding area is set for each side edge of the paper P, and the set protruding area is stored in the first protruding area memory 93D. Then, borderless printing is realized by ejecting ink in accordance with the protruding area stored in the first protruding area memory 93D. The protruding area can be reduced to a predetermined range in the left-right direction 9 (a range in which image quality in borderless printing can be guaranteed). In the present embodiment, specifically, the protruding area is in the range of 0.17 mm to 1.0 mm, and can be set in units of 0.17 mm, which is the resolution of the linear encoder 69.

  The first protrusion area memory 93D stores an extension area that is set based on the positions of both ends of the sheet P stored in the first both-end edge memory 93A, and the second protrusion area memory 93E stores the third protrusion area memory 93E. A protrusion area set based on the positions of both ends of the sheet P stored in the both-end memory 93C is stored. Further, the protruding areas stored in the first protruding area memory 93D and the second protruding area memory 93E are used as a judgment as to whether or not the rib 81 is in the protruding area. Of the rib 81 stored in the ROM 92 within the encoder count value from the ink discharge start position to the left end of the paper P and within the encoder count value from the right end of the paper P to the ink discharge end position outside the paper P. It is determined whether a count value exists.

  The image data memory 93F stores image data when the carriage 31 scans and the recording head 30 ejects ink. This image data stores 8-bit data (1 byte) per pixel. The 8-bit data is larger than the first droplet, not ejecting every 2 bits for each color of cyan (C), magenta (M), yellow (Y), and black (K). Information such as ejection of the second droplet and ejection of a third droplet larger than the second droplet is stored. Further, four pieces of these 8-bit data are stored in one block. Therefore, 32-bit data (4 bytes) is stored in a block indicating one address, that is, data for four pixels is stored. A plurality of these one blocks are prepared, and a plurality of blocks are stored in a state managed for each of a plurality of addresses.

  Therefore, when an image is recorded on the paper P, according to the image data stored in the image data memory 93F, specifically, based on the 32-bit data indicated by one block stored at the read address. The carriage 31 is scanned, and the recording head 30 is driven to eject ink of each color. When performing borderless printing, the image data memory 93F stores image data composed of the size of the paper P in the left-right direction 9 and the size of the protruding area 9 set in each side edge of the paper P in the left-right direction 9. Remembered. When the protruding area is reduced or enlarged, it is realized by reducing or increasing the range of addresses to be read.

  The dirt flag memory 93G (an example of the first storage unit and the second storage unit of the present invention) selectively stores the first information (an example of the first information of the present invention) and the second information. For example, the first information is stored when it is determined that the rib 81 of the platen 34 may be stained. The second information is stored when it is determined that there is no possibility of the rib 81 becoming dirty. In the present embodiment, the first information is stored in the dirt flag memory 93G, and ON is stored in the dirt flag memory 93G. Here, the case where the rib 81 of the platen 34 may be soiled is a time when the rib 81 of the platen 34 is included in the minimum protrusion region D0 in this embodiment described later.

  The EEPROM 94 stores settings, flags, and the like that should be retained even after the power is turned off.

<Operation of Embodiment>
Next, the borderless printing operation by the multifunction machine 10 according to the present embodiment will be described with reference to FIGS. Borderless printing refers to recording an image without providing a margin at the edge of the paper P. In this case, the ink ejection area has a size in the horizontal direction 9 of the paper P and a size in the horizontal direction 9 of the paper P. It consists of a protruding area that protrudes from the size. The multifunction machine 10 according to the present embodiment performs various controls when the rib 81 is included in the protruding area.

  As described above, the protruding area is the encoder count value from the ink discharge start position outside the paper P to the left end of the paper P, and the encoder count value from the right edge of the paper P to the ink discharge end position outside the paper P. It is.

<When NO is determined in S55 and S70 of FIGS. 12 and 13>
<< When using standard paper P1 >>
In the following, a case where a standard paper (hereinafter referred to as paper P1) is printed without margins without being skewed will be described with reference to FIGS. 9 to 13 and 14A. Note that the skew refers to a case where NO is determined in S55 and S70 of FIGS. Specifically, the skew of the paper P is specifically determined by the linear encoder between the side edge positions of the paper P stored in the first side edge memory 93A and the side edge positions of the paper P stored in the second side edge memory 93B. A case where the resolution is greater than 69 (0.17 mm) is shown. Further, the standard paper indicates a paper stored in advance in the multifunction machine 10. FIG. 14A is a diagram showing the relative positions of the paper P1, the rib 81, and the protruding area when borderless printing is performed on the paper P1 that is not skewed.

  As shown in FIG. 9, first, when the borderless printing process is started by operating an externally connected PC or the operation panel 16, the control unit 90 stores the memories 93A to 93E in the RAM. Initialization (Step 1, step is hereinafter abbreviated as S). Then, the control unit 90 drives the paper feed motor 71 to feed the paper P1 placed on the paper feed tray 20 by the feeding unit 17 toward the recording unit 24 (S2), and the paper P1 Cueing for feeding is performed to a cueing position that can be detected by the media sensor 52 (S3). Specifically, as shown in FIG. 7, the front end of the paper P <b> 1 is fed to a position facing the recording head 30. When the paper is fed to the cueing position, the media sensor 52 detects the presence or absence of the paper on the platen 34 (S4). Note that the presence / absence of the sheet is detected by scanning the carriage 31 in advance so that the sheet P1 to be fed by the media sensor 52 exists before the sheet P1 is fed to the cueing position. Let me. If the control unit 90 determines that there is no paper P1 as detected by the media sensor 52 (NO in S5), an error is displayed on the display unit 18 (S16), and the borderless printing is terminated.

  When the control unit 90 determines that the sheet P1 is present (YES in S5), the control unit 90 scans the carriage 31 so as to cross both side edges in the left-right direction 9 of the sheet P1 at the cueing position. Then, the both side edge determination of the paper P1 is performed by controlling the media sensor 52 (S6, which is an example of both end determination means of the present invention). At this time, the determined both-side edge positions of the sheet are stored in the first both-side edge memory 93A. Next, the center position in the left-right direction 9 of the paper P1 at the cueing position is specified (S7).

  Then, the control unit 90 matches the center of the ink discharge start position and the ink discharge end position when discharging ink onto the paper P1 with the specified center position of the paper P1 (S8). Thereby, the ink discharge start position and the ink discharge end position are determined. Thereafter, the control unit 90 sets the maximum protrusion area D (an example of the first area and the second area of the present invention) in the left-right direction 9 based on the determined positions of both side edges of the paper P1, and the first protrusion It memorize | stores in the area | region memory 93D (S9, an example of the 1st area | region setting means of this invention, a 2nd area | region setting means). It should be noted that the maximum protruding area D is secured by 1 mm on each side end in the left-right direction 9 of the paper P.

  Next, the control unit 90 proceeds to a protruding area setting process (S10) before printing. When the protruding area setting process is started, first, the controller 90 has the rib 81 in the leftmost protruding area D (an example of the first area of the present invention) stored in the first protruding area memory 93D. (S20, an example of the first determining means of the present invention). Specifically, it is determined whether or not the encoder count value of the rib 81 stored in the ROM 92 exists in the encoder count value from the ink discharge start position outside the paper P1 to the left end of the paper P1. In the present embodiment, as shown in FIG. 14A, the control unit 90 determines that there is no rib in the set left maximum protrusion region D (region surrounded by a dotted line) ( NO in S21).

  Next, the control unit 90 determines whether or not the rib 81 is present in the maximum protrusion area D on the right side (an example of the second area of the present invention) stored in the first protrusion area memory 93D (S24). An example of the second region determination means of the present invention). Specifically, it is determined whether or not the encoder count value of the rib 81 stored in the ROM 92 exists in the encoder count value from the right end of the paper to the ink discharge end position outside the paper P1. In the present embodiment, as shown in FIG. 14A, the control unit 90 determines that no rib exists in the set right maximum protrusion area D (area surrounded by a dotted line) ( NO in S24).

  Then, the control unit 90 determines the ink discharge start position and the ink discharge end position from the maximum protrusion area D on both sides stored in the first protrusion area memory 93D (S29). Next, the control unit 90 sets a range of addresses from which the image data stored in the image data memory 93F is read so that the ink is ejected for the distance from the determined ink ejection start position to the ink ejection end position. Specify (S30). Next, the process proceeds to a printing process (S15, see FIG. 11). Note that S29 and S30 are examples of the discharge region setting means of the present invention.

  As shown in FIG. 11, when the printing process is started, the control unit 90 first reads the ink discharge start position and the ink discharge end position determined in S29 and the image data designated in S30. In accordance with the address range, the carriage 31 is scanned and ink is ejected from the recording head 30 (S40, which is an example of the control means of the present invention). Next, the control unit 90 determines whether or not the sheet has been conveyed by a certain distance (specifically, 0.5 inch) or more since the previous determination on both sides of the sheet (S41). If it is determined by the control unit 90 that the sheet has not been conveyed for a certain distance (YES in S41), the control unit 90 drives the conveyance roller pair 54 and the discharge roller pair 55 to convey the sheet P1 (S43), and the control is performed. If it is determined by section 90 that printing of one sheet has not been completed (NO in S44), the process returns to S40 again. At this time, the conveyance amount of the sheet by the conveyance roller pair 54 and the discharge roller pair 55 is smaller than a certain distance (0.5 inch), for example, 0.1 inch. When the processes of S40, S41, S43, and S44 are repeated and the control unit 90 determines that the paper has been conveyed by a certain distance or more from the determination of both side edges of the paper (NO in S41), printing for determining both side edges of the paper being printed The both-side edge determination process for the middle sheet is started (see S42, FIG. 12 and FIG. 13).

  As shown in FIG. 12, when the paper both-side edge determination process during printing is started, the control unit 90 performs both-side edge determination for the paper being printed by the media sensor 52 and also determines the determined position on both sides of the paper. It memorize | stores in the 1st both-ends memory 93A (S50). At this time, the both-side edge positions of the paper at the previous determination stored in the first both-side edge memory 93A are moved and stored in the second both-side edge memory 93B by the control unit 90. Then, based on the both-side edge positions of the paper determined in S50, the maximum protruding area D on both sides is set by the control unit 90 (S51).

  The control unit 90 identifies the tendency of the skew of the paper from the previous and current side edge positions stored in the first both-side edge memory 93A and the second both-side edge memory 93B (S52). Thereafter, the control unit 90 calculates the estimated both-side edge positions of the sheet P1 when the sheet P is transported by 0.1 inch from the currently determined position of the sheet P1, based on the skew of the identified sheet. The calculated estimated both end positions are stored in the third both end memories in 93C (S53). Then, based on the estimated both-side end positions stored in the third both-side end memory 93C, the maximum protruding area D on both sides of the estimated side is set and stored in the second protruding area memory 93E (S54). Specifically, the maximum protruding area D on both sides of the estimation is specifically the encoder count value from the estimated ink ejection start position to the right edge of the estimated paper P1, and the left edge of the estimated paper P1 to the estimated ink ejection end position. Encoder count value.

  Further, the control unit 90 determines whether or not the currently determined left end position of the sheet P1 stored in the second both-side end memory 93B and the estimated left end position of the sheet P1 stored in the third both-side end memory 93C are shifted. Is determined (S55).

  When the paper P1 is placed and fed in a state where the pair of guide plates 101 of the paper feed tray 20 are correctly operated so as to have the same distance as the length in the left-right direction 9 of the standard paper, the paper P1 is fed. The sheet is fed to the recording unit 24 without being skewed. Accordingly, the paper P1 is not skewed even when fed from the paper feed tray 20 and transported by the recording unit 24, so the paper P1 stored in the second both-end memory 93B and the third both-end memory 93C. The both-side end positions coincide with each other (the both-ends also coincide with each other even when they are shifted in the left-right direction 9 within the resolution of the linear encoder 69 or less), and the control unit 90 determines NO in S55. To do. If the control unit 90 determines NO in S57, the control unit 90 uses the largest left overhang area D stored in the first overhang area memory 93D as it was previously determined (S63).

  Next, as shown in FIG. 13, the control unit 90 estimates the right sheet position of the currently determined sheet P1 stored in the second both-end memory 93B and the estimated sheet stored in the third both-end memory 93C. It is determined whether or not the right end position of P1 deviates (S70).

  In the first embodiment, the sheet P1 is not skewed even when being fed from the sheet feeding tray 20 and when being transported by the recording unit 24. Therefore, the second both-end memory 93B and the third both-end memory 93C are used. The two side end positions of the paper P1 stored in the first and second positions coincide with each other (the two side ends coincide with each other even when they are shifted in the left-right direction 9 within the resolution of the linear encoder 69 or less), and the control unit 90 Determines NO in S55. If the control unit 90 determines NO in S70, the control unit 90 uses the maximum right-side protruding area D stored in the first protruding area memory 93D when previously determined (S78).

  Then, the control unit 90 determines the ink discharge start position and the ink discharge end position from the maximum protrusion area D on both sides stored in the first protrusion area memory (S78). Next, the control unit 90 sets a range of addresses from which the image data stored in the image data memory 93F is read so that the ink is ejected for the distance from the determined ink ejection start position to the ink ejection end position. Designation is made (S79), and the both-sides edge determination process during printing ends.

  When the paper both side edge determination process during printing is completed, the paper P1 is transported (S43). If printing for one sheet is not completed (NO in S44), the ink ejection start position and ink ejection end position determined in S78 and the address range when reading the image data designated in S79 are determined. Then, the controller 90 scans the carriage 31 and ejects ink from the recording head 30 (S40). Then, the arbitrary processing of S40 to S44 described above is repeated until printing for one sheet is completed, and if the control unit 90 determines that printing for one sheet has been completed (YES in S44), the control is performed. The unit 90 discharges the sheet onto the discharge tray 21 (S45), ends the printing process, and proceeds to S12 of the flowchart shown in FIG.

  In S12, the control unit 90 determines whether ON is stored in the dirt flag memory 93G. If control unit 90 determines that ON is not stored in dirt flag memory 93G (NO in S12), then control unit 90 determines whether or not the next page is printed (S15). If the control unit 90 determines that the next page is printed (NO in S20), the process returns to S1 again, and the borderless printing process for the paper P of the next page is started. If control unit 90 determines that the next page is not printed (YES in S15), the borderless printing process is terminated.

<< When using non-standard-size paper P2 >>
Hereinafter, a case where non-standard-size paper (hereinafter referred to as paper P2) is printed without being skewed will be described with reference to FIGS. 9 to 13 and 14B. The non-standard-size paper indicates a paper that is not stored in advance in the multifunction machine 10. FIG. 14B is a diagram showing the relative positions of the paper P2, the rib 81, and the protruding area when borderless printing is performed on the paper P2 that is not skewed.

  As shown in FIG. 9, when borderless printing processing is started by operating an externally connected PC or the operation panel 16, the control unit 90 initializes each of the memories 93A to 93E in the RAM. (S1). The processing in S1 to S9 is the same as that in the case where the above-described standard paper P1 is printed without borders without being skewed, and is therefore omitted.

  When the process of S9 ends, the control unit 90 then proceeds to a protruding area setting process (S10) before printing. When the protruding area setting process is started, first, the control unit 90 determines whether or not the rib 81 is in the leftmost protruding area D stored in the first protruding area memory 93D (S20). . When the sheet P2 as shown in FIG. 14B is fed, the rib 81 is present in the maximum protrusion area D on the left side surrounded by a dotted line. Therefore, when printing the paper P2 without borders, the control unit 90 has the rib 81 in the left maximum protrusion area D based on the maximum protrusion area D on the left side stored in the first protrusion area memory 93D. It is determined that it exists (YES in S20). It should be noted that the left maximum protrusion area D is 1 mm on the left side in the left-right direction 9 of the paper P.

  Next, from within the minimum protrusion area D0 on the left side (which is an example of the fifth area of the present invention), the control unit 90 determines whether or not the rib 81 is present in the minimum protrusion area D0 on the left side ( S21). In order to sufficiently guarantee the image quality of borderless printing, the size in the left-right direction 9 is normally set to 1 mm as the leftmost protruding area D, but if the image quality can be guaranteed, the protruding area D is It can be reduced to 0.17 mm (minimum protruding area D0). Note that, as shown in FIG. 14B, a region D0 surrounded by an alternate long and short dash line is the smallest protruding region. When the paper P2 is fed, as shown in FIG. 14B, the rib 81 does not exist in the minimum protrusion area D0 on the left side. Therefore, NO in the left minimum protrusion region D0 set from the left maximum protrusion region D stored in the first protrusion region memory 93D).

  If it is determined that there is no rib 81 in the minimum protrusion area D0 on the left side (NO in S21), the control unit 90 allows the left protrusion area to avoid the rib 81 (an example of the third area of the present invention). Until then, the left protruding area D1 that can avoid the rib 81 nearest to the left end of the sheet P2 is reset, and the reset right protruding area D1 is stored in the first protruding area memory 93D (S23, according to the present invention). This is an example of third area setting means). Specifically, the encoder count value on the left side protruding area D1 that can avoid the rib 81, that is, the ink discharge start position, is between 0.17 mm and less than 1.0 mm from the left end of the paper P2 further to the left side. It is set at the position. Further, the protruding area D1 that can avoid the rib can be set for each resolution unit of the linear encoder 69 (specifically, 150 dpi, 0.17 mm, an example of the fifth distance of the present invention). In FIG. 14B, the region surrounded by the solid line is the protruding region D1 that can avoid the reset rib 81. Further, the left protruding area D1 that can avoid the rib 81 is set as the maximum value of the resolution of the linear encoder 69 for each unit.

  Next, the control unit 90 determines whether or not there is a rib 81 in the maximum protrusion area D on the right side stored in the first protrusion area memory 93D (S24). When the paper P2 as shown in FIG. 14B is fed, the rib 81 is present in the maximum protrusion area D on the right side surrounded by the dotted line. Therefore, when printing the paper P2 without borders, the control unit 90 has the rib 81 in the right maximum protrusion area D based on the maximum right protrusion area D stored in the first protrusion area memory 93D. It is determined that it exists (YES in S24). The maximum protrusion area D on the right side is secured about 1 mm on the right side in the left-right direction 9 of the paper P.

  Next, it is determined whether or not there is a rib in the minimum protrusion area D0 on the right side (which is an example of the fifth area of the present invention) (S25). In order to sufficiently guarantee the image quality of borderless printing, the size of the rightward and leftward extension area 9 is normally set to 1 mm as the maximum protrusion area D on the right side. It can be reduced to 0.17 mm (minimum protruding area D0). Note that, as shown in FIG. 14B, a region D0 surrounded by an alternate long and short dash line is the smallest protruding region. When the paper P2 is fed, as shown in FIG. 14B, the rib 81 does not exist in the minimum protrusion area D0 on the right side. Therefore, the control unit 90 determines that there is no rib 81 in the minimum protrusion area D0 on the right side from the minimum protrusion area D0 on the right side set from the maximum protrusion area on the right side stored in the first protrusion area memory 93D. (NO in S25).

  If it is determined that there is no rib 81 in the minimum protrusion area D0 on the right side (NO in S25), the control unit 90 resets the right protrusion area D1 that can avoid the right-most protrusion rib 81 and restarts. The set right protruding area D1 is stored in the first protruding area memory 93D (S27, which is an example of the fourth area setting means of the present invention). More specifically, the encoder count value on the right side protruding area D1 where the rib 81 can be avoided, that is, the ink discharge end position is between 0.17 mm and less than 1.0 mm from the right end of the paper P2 to the right side. It is set at the position. In FIG. 14B, the region surrounded by the solid line is the protruding region D1 that can avoid the reset rib 81. Further, the right protruding area D1 that can avoid the rib 81 is set as the maximum value of the resolution of the linear encoder 69 for each unit.

  Then, the control unit 90 determines the ink discharge start position and the ink discharge end position from the protruding areas D1 on both sides that can avoid the reset rib 81 stored in the first protruding area memory 93D (S29). Next, the control unit 90 sets a range of addresses from which the image data stored in the image data memory 93F is read so that the ink is ejected for the distance from the determined ink ejection start position to the ink ejection end position. Specify (S30). Next, the process proceeds to a printing process (S11, see FIG. 11).

  Processing during printing (S11) and paper both-side edge determination processing during printing (S42), S50 to S55 and S63 shown in the flowchart of FIG. 12, or S70 shown in the flowchart of FIG. Steps S77 to S79 are the same as those in the case where the paper P1 is printed without borders without being skewed.

  Further, since the printing process (S11) is completed and the processes of S12 and S15 shown in the flowchart of FIG. 9 are the same as the case where the paper P1 is printed without margins without being skewed, Omitted.

<< When using non-standard-size paper P3 >>
Hereinafter, the case where the non-standard-size paper (hereinafter referred to as paper P3) is printed without a skew and the ribs are soiled will be described with reference to FIGS. 9 to 13 and 14C. FIG. 14C is a diagram showing the relative positions of the paper P3, the rib 81, and the protruding area when borderless printing is performed on the paper P3 that is not skewed.

  As shown in FIG. 9, when borderless printing processing is started by operating an externally connected PC or the operation panel 16, the control unit 90 initializes each of the memories 93A to 93E in the RAM. (S1). The processing from S1 to S9 is the same as that in the case where the paper P1 is printed without margins without being skewed, and is therefore omitted.

  When the process of S9 ends, the control unit 90 then proceeds to a protruding area setting process (S10) before printing. When the protruding area setting process is started, first, the control unit 90 determines whether or not the rib 81 is in the leftmost protruding area D stored in the first protruding area memory 93D (S20). . When the sheet P3 as shown in FIG. 14C is fed, the rib 81 is present in the maximum protrusion area D on the left side surrounded by a dotted line. Accordingly, when printing the paper P3 without borders, the control unit 90 has the rib 81 in the left maximum protrusion area D based on the maximum protrusion area D on the left side stored in the first protrusion area memory 93D. It is determined that it exists (YES in S20). It should be noted that the largest protrusion area D on the left side is secured 1 mm on the left side in the left-right direction 9 of the paper P3.

  If YES is determined in S20, the control unit 90 then determines whether or not there is a rib in the minimum protrusion area D0 on the left side (S21, an example of the third determining means of the present invention). As shown in FIG. 14C, the area D0 surrounded by the alternate long and short dash line is the minimum protrusion area D0, and the minimum protrusion area D0 is 0.17 mm on the left side in the left-right direction 9 of the paper P3. Is done. When the paper P3 is fed, as shown in FIG. 14C, the rib 81 exists in the minimum protrusion area D0. Therefore, from the left minimum protrusion area D0 set from the left maximum protrusion area D stored in the first protrusion area memory 93D, the control unit 90 has the rib 81 in the left minimum protrusion area D0. Judgment is made (YES in S21).

  In this case, since ink is ejected onto the rib 81, the control unit 90 stores ON in the dirt flag memory 93G (S22).

  When the processing of S24 is completed, the control unit 90 determines whether or not the rib 81 is present in the maximum protrusion area D on the right side stored in the first protrusion area memory 93D (S24). When the sheet P3 as shown in FIG. 14C is fed, the rib 81 is present in the maximum protrusion area D on the right side surrounded by the dotted line. Therefore, when printing the paper P3 without borders, the control unit 90 has the ribs 81 in the maximum right protrusion area D based on the maximum protrusion area D on the right side stored in the first protrusion area memory 93D. It is determined that it exists (YES in S24). Note that the maximum protrusion area D on the right side is secured 1 mm on the left side in the left-right direction 9 of the paper P3.

  Next, the control unit 90 determines whether or not there is a rib in the minimum protrusion area D0 on the right side (S25, an example of the fourth determination unit of the present invention). As shown in FIG. 14C, the area D0 surrounded by the alternate long and short dash line is the minimum protrusion area D0, and the minimum protrusion area D0 is 0.17 mm on the right side in the left-right direction 9 of the paper P3. Is done. When the paper P3 is fed, as shown in FIG. 14C, the rib 81 exists in the minimum protrusion area D0. Therefore, the control unit 90 has the rib 81 in the minimum protrusion area D0 on the right side from the minimum protrusion area D0 on the right side set from the maximum protrusion area D on the right side stored in the first protrusion area memory 93D. Judgment is made (YES in S25).

  Next, the control unit 90 determines whether or not OFF is stored in the dirt flag memory 93G (S26). Since the dirt flag memory 93G has already been stored ON in S22, NO is determined in S26. To do. On the other hand, for example, when the rib 81 does not exist in the minimum protrusion area D0 on the left side and the rib 81 exists in the minimum protrusion area D0 on the right side, OFF is stored in the dirt flag memory 93G. (YES in S26), ON is stored in the dirt flag memory 93G (S28).

  Then, the control unit 90 determines the ink discharge start position and the ink discharge end position from the maximum protrusion area D on both sides stored in the first protrusion area memory 93D (S29). In this case, the largest protruding area D is selected as the protruding area on both sides, not the smallest protruding area D0. Next, the control unit 90 sets a range of addresses from which the image data stored in the image data memory 93F is read so that the ink is ejected for the distance from the determined ink ejection start position to the ink ejection end position. Specify (S30). Next, the process proceeds to a printing process (S11, see FIG. 11).

  Processing during printing (S11) and paper both-side edge determination processing during printing (S42), S50 to S55 and S63 shown in the flowchart of FIG. 12, or S70 shown in the flowchart of FIG. Steps S77 to S79 are the same as those in the case where the paper P1 is printed without borders without being skewed.

  When the printing process (S11) ends, the process proceeds to S12. Since ON is stored in the dirt flag memory 93 (YES in S12), the control unit 90 causes the display unit 18 to display that the rib 81 may be dirty and to request cleaning (S13). ). Thereafter, while the opening / closing sensor 19 does not detect that the cover 12 has been opened (NO in S14), the control unit 90 continues to display on the display unit 18 and confirms that the cover 12 has been opened. If detected (YES in S13), display on the display unit 18 is stopped, and then the control unit 90 determines whether or not the next page is printed (S15). If control unit 90 determines that there is printing of the next page (NO in S15), the process returns to S1 again, and borderless printing processing for the paper P of the next page is started. If control unit 90 determines that the next page is not printed (YES in S15), the borderless printing process is terminated.

<When YES is determined in S55 and S70 of FIGS. 12 and 13>
<< When using non-standard-size paper P2 >>
Hereinafter, the case where the paper P2 is printed in a skewed state will be described with reference to FIGS. 9 to 13 and FIG. Specifically, the skew of the sheet P is specifically defined by the positions of the both ends of the sheet P stored in the first both-end memory 93A and the positions of both ends of the sheet P stored in the second both-end memory 93B. The case where it is larger than the resolution (0.17 mm) of the linear encoder 69 is shown. FIG. 15 is a diagram showing the relative positions of the paper P2, the rib 81, and the protruding area when borderless printing is performed on the skewed paper P2. FIG. 15A is a diagram illustrating the position of the paper P2 after the first paper side edge determination is performed. FIG. 15B is a diagram illustrating the position of the sheet P2 when the sheet P2 at the position of FIG. FIG. 15C shows a case where the sheet is transported once from the position shown in FIG. 15B, which is estimated from the paper position shown in FIGS. 15A and 15B (0.1). FIG. 6 is a diagram illustrating a position of a sheet of paper P2 when being conveyed in inches.

  As shown in FIG. 9, when borderless printing processing is started by operating an externally connected PC or the operation panel 16, the control unit 90 initializes each of the memories 93A to 93E in the RAM. (S1). Since the processing of S1 to S9 is the same as the above-described content, it is omitted. When the process of S9 ends, the control unit 90 then proceeds to a protruding area setting process (S10) before printing. When the protruding area setting process is started, first, the control unit 90 determines whether or not the rib 81 is in the leftmost protruding area D stored in the first protruding area memory 93D (S20). . When the sheet P2 as shown in FIG. 15A is fed in a skewed state, the rib 81 is present in the maximum protrusion area D on the left side surrounded by a dotted line. Therefore, when borderless printing is performed on the paper P2, the control unit 90 determines that the ribs 81 are present in the maximum protrusion area D based on the maximum protrusion area D on the left side stored in the first protrusion area memory 93D. Judgment is made (YES in S20). It should be noted that the largest protrusion area D on the left side is secured 1 mm on the left side in the left-right direction 9 of the paper P3.

  Next, it is determined whether or not there is a rib in the minimum protrusion area D0 on the left side (area surrounded by an alternate long and short dash line in FIG. 15) (S21). When the sheet P2 is fed in a skewed state, the rib 81 does not exist in the minimum protrusion area D0 on the left side of the sheet P1, as shown in FIG. Therefore, the control unit 90 determines that there is no rib 81 in the left minimum protrusion area D0 from the left minimum protrusion area D0 set from the left protrusion area D stored in the first protrusion area memory 93D. (NO in S21).

  If it is determined that there is no rib 81 in the minimum protrusion area D0 on the left side (NO in S21), the control unit 90 causes the left protrusion area D1 on the left side of the paper P2 to the area D1 where the left protrusion area can avoid the rib 81. (A region surrounded by a solid line in FIG. 15) is reset, and the reset right protruding area D1 is stored in the first protruding area memory 93D (S23).

  Thereafter, the control unit 90 determines whether or not there is a rib 81 in the maximum protrusion area D on the right side stored in the first protrusion area memory 93D (S24). When the sheet P2 as shown in FIG. 15A is fed in a skewed state, the rib 81 is present in the largest protruding area D on the right side surrounded by a dotted line. Therefore, when performing borderless printing on the paper P2, the control unit 90 determines that the rib 81 is located in the maximum protrusion area D based on the maximum protrusion area D on the right side stored in the first protrusion area memory 93D. Judgment is made (YES in S24). The maximum protrusion area D on the right side is secured 1 mm on the right side in the left-right direction 9 of the paper P3.

  Next, it is determined whether or not there is a rib in the minimum protrusion area D0 (area surrounded by a one-dot chain line in FIG. 15) (S25). When the paper P2 is fed in a skewed state, as shown in FIG. 15A, the rib 81 does not exist in the minimum protrusion area D0 on the right side of the paper P1. Therefore, the control unit 90 determines that there is no rib 81 in the right minimum protrusion area D0 from the right minimum protrusion area D0 set from the right protrusion area D stored in the first protrusion area memory 93D. (NO in S25).

  If it is determined that there is no rib 81 in the minimum protrusion area D0 on the right side (NO in S25), the control unit 90 extends to the area D1 on the right side of the paper P2 until the right protrusion area can avoid the rib 81. (A region surrounded by a solid line in FIG. 15) is reset, and the reset right protruding area D1 is stored in the first protruding area memory 93D (S28). When the paper P2 is located at a position as shown in FIG. 15A, the right protruding area D1 that can avoid the rib 81 is set to D1 = D0 (0.17 mm).

  Then, the control unit 90 determines the ink discharge start position and the ink discharge end position from the protruding areas D1 on both sides that can avoid the reset rib 81 stored in the first protruding area memory 93D (S29). Next, the control unit 90 sets a range of addresses from which the image data stored in the image data memory 93F is read so that the ink is ejected for the distance from the determined ink ejection start position to the ink ejection end position. Specify (S30). Next, the process proceeds to a printing process (S11, see FIG. 11).

  Since the printing process (S15) is the same as that described above, a description thereof will be omitted. When the overhang area setting process (S42) during printing is started, the control unit 90 determines both side edges of the paper being printed by the media sensor 52, and the determined both-side edge position of the paper is the first both-side edge memory 93A. (S50). At this time, the both-side edge positions of the paper at the previous determination stored in the first both-side edge memory 93A are moved and stored in the second both-side edge memory 93B by the control unit 90. Then, based on the both-side edge positions of the paper determined in S50, the maximum protruding area D on both sides is set by the control unit 90 (S51).

Next, the control unit 90 specifies the tendency of the skew of the paper P2 from the previous and current side edge positions stored in the first both-side edge memory 93A and the second both-side edge memory 93B (S52). . As shown in FIGS. 15A and 15B, the sheet P2 is stored in the first both-side edge memory A and the second both-side edge memory 93B. Are different, the paper is skewed. Specifically, the positions of the both-side edges of the previous and current sheets stored in the first both-side edge memory A and the second both-side edge memory 93B are greatly different from the resolution (0.17 mm) of the linear encoder 69. Thereafter, the control unit 90 calculates the estimated both-side edge positions of the sheet P1 when the sheet P is transported by 0.1 inch from the currently determined position of the sheet P1, based on the skew of the identified sheet. The calculated estimated both end positions are stored in the third both end memories in 93C (S53). The position of the sheet P2 at the estimated position at this time is shown in FIG. Note that S52 and S53 are examples of the calculation means of the present invention.

  Then, based on the estimated both end positions stored in the third both end memory 93C, the maximum protruding area D on both sides of the estimated side is set and stored in the second protruding area memory 93E (S54, the first of the present invention). An example of 6 area setting means and 7th area setting means). Further, the control unit 90 determines whether or not the currently determined left end position of the sheet P1 stored in the second both-side end memory 93B and the estimated left end position of the sheet P1 stored in the third both-side end memory 93C are shifted. (S55, an example of the fifth determining means of the present invention). As described above, since the sheet P2 is fed in a skewed state, if it is determined that the control unit 90 is displaced (YES in S55), then the control unit 90 is stored in the second both-end memory 93B. It is determined whether or not there is a rib 81 between the left end position of the sheet P2 to be stored and the left end position of the sheet P2 stored in the third both-side end memory 93C (S56). Since the position of the rib 81 is stored in advance in the ROM 92, the position of the rib 81 stored in the ROM 92 is referred to in this process.

  As shown in FIGS. 15B and 15C, there is no rib 81 between the left end positions, so the control unit 90 includes the second both end memory 93B, the third both end memory 93C, With reference to the count value of each encoder stored in ROM 92, it is determined that there is no rib 81 (NO in S56). Thereafter, the control unit 90 determines whether or not the rib 81 is in the estimated leftward maximum protrusion area D (an example of the sixth area of the present invention) stored in the second protrusion area memory 93E. (S57, an example of sixth determination means of the present invention). As shown in FIG. 15C, the rib 81 is in the largest protrusion region D on the left side of the estimated paper P2. Therefore, the control unit 90 refers to the second protruding area memory 93E and determines that the rib 81 is present in the leftmost protruding area D stored in the second protruding area memory 93E (YES in S57).

  Thereafter, the controller 90 determines whether the rib 81 is in the left minimum protrusion area D0 (an example of the tenth area of the present invention) based on the left maximum protrusion area D stored in the second protrusion area memory 93E. It is determined whether or not (S59, an example of the eighth determining means of the present invention). As shown in FIG. 15C, there is no rib 81 in the minimum protrusion region D0 on the left side of the estimated paper P2. Therefore, the control unit 90 determines that there is no rib in the minimum protrusion area D0 on the left side (YES in S59).

  Next, the control unit 90 resets the left protruding area D1 (an example of the eighth area of the present invention) on the left side of the sheet P2 until the left protruding area can avoid the rib 81, and reset the left side. The protruding area D1 is stored in the first protruding area memory 93D (S61, an example of the eighth area setting means of the present invention).

  When the processing of S61 is completed, as shown in FIG. 13, the control unit 90 next stores the right end position of the sheet P1 determined this time stored in the second both-end memory 93B and the third both-end memory 93C. It is determined whether or not the right edge position of the estimated sheet P1 stored is deviated (S70, an example of a fifth determination unit of the present invention). As described above, since the paper P2 is being fed in a skewed state, if it is determined that the control unit 90 is displaced (YES in S70), then the control unit 90 is stored in the second both-end memory 93B. It is determined whether or not there is a rib 81 between the right end position of the sheet P2 and the right end position of the sheet P2 stored in the third both-side end memory 93C (S71).

  As shown in FIGS. 15 (B) and 15 (C), since there is no rib 81 between each right end position, the control unit 90 includes a second both end memory 93B, a third both end memory 93C, With reference to the count value of each encoder stored in ROM 92, it is determined that there is no rib 81 (NO in S71). Thereafter, the control unit 90 determines whether or not the rib 81 is present in the maximum protrusion area D on the right side stored in the second protrusion area memory 93E (an example of the seventh area of the present invention) ( S72, an example of seventh determination means of the present invention). As shown in FIG. 15C, the rib 81 is in the largest protrusion region D on the right side of the estimated paper P2. Therefore, the control unit 90 refers to the second protrusion area memory 93E and determines that the rib 81 is present in the maximum protrusion area D on the right side stored in the second protrusion area memory 93E (YES in S72).

  Thereafter, the control unit 90 determines whether or not there is a rib 81 in the minimum protrusion area D0 on the right side based on the maximum protrusion area D stored in the second protrusion area memory 93E (an example of the tenth area of the present invention). (S74, an example of the ninth determination means of the present invention). As shown in FIG. 15C, the rib 81 is in the smallest protrusion region D0 on the right side of the estimated paper P2. Therefore, the control unit 90 determines that the rib 81 is within the minimum protrusion area D0 on the right side (NO in S74).

  Next, with reference to the dirt flag memory 93G, the control unit 90 stores ON in the dirt flag memory 93G (S75) if OFF is stored in the dirt flag memory 93G (NO in S73). If ON is stored in memory 93G (YES in S73), the process proceeds to S78. In the process of S78, the control unit 90 determines the ink discharge start position and the ink discharge end position from the maximum protrusion area D on both sides stored in the first protrusion area memory (S78). In this case, the ink discharge start position and the ink discharge end position are determined based on the protrusion area D1 that can avoid the reset rib 81 in the right protrusion area, and the maximum protrusion area D in the left protrusion area. . Next, the control unit 90 sets a range of addresses from which the image data stored in the image data memory 93F is read so that the ink is ejected for the distance from the determined ink ejection start position to the ink ejection end position. Designation is made (S79), and the both-sides edge determination process during printing ends.

  Then, the paper both-side edge determination process during printing is completed, and the process returns to S42 shown in FIG. 11 again to transport the paper P2 (S43). If printing for one sheet has not been completed (NO in S43), the ink ejection start position and ink ejection end position determined in S78 and the address range when reading the image data designated in S79 are determined. Then, the controller 90 scans the carriage 31 and ejects ink from the recording head 30 (S40). Then, the arbitrary processing of S40 to S44 described above is repeated until printing for one sheet is completed, and if the control unit 90 determines that printing for one sheet is completed (YES in S44), the discharge is performed. The paper is discharged onto the paper tray 21 (S45), the printing process is terminated, the process returns to S11 in the flowchart shown in FIG. 9, and the process proceeds to S12.

  Since ON is stored in the dirt flag memory 93G (YES in S12), the control unit 90 causes the display unit 18 to display that the rib 81 may be dirty and to request cleaning (S13). ). Thereafter, while the opening / closing sensor 19 does not detect that the cover 12 has been opened (NO in S14), the control unit 90 continues to display on the display unit 18 and confirms that the cover 12 has been opened. If detected (YES in S14), display on the display unit 18 is stopped, and then the control unit 90 determines whether or not there is a next page (S15). If control unit 90 determines that there is printing of the next page (NO in S15), the process returns to S1 again, and borderless printing processing for the paper P of the next page is started. If control unit 90 determines that the next page is not printed (YES in S20), the borderless printing process is terminated.

  When the rib 81 is between the left end position of the sheet P2 stored in the first both-end memory 93B and the left end position of the sheet P2 stored in the third both-end memory 93C (S56), or If there is a rib 81 between the right end position of the sheet P2 stored in the second both-end memory 93B and the right end position of the sheet P2 stored in the third both-end memory 93C (S71), The rib 81 is present in the minimum protrusion area D0 when the sheet is conveyed for a predetermined distance. Therefore, the control unit 90 refers to the dirt flag memory 93G, and stores “ON” in the dirt flag memory 93G if “OFF” is stored in the dirt flag memory 93G (YES in S58, 73) (S60, S75). If ON is stored in dirt flag memory 93G (YES in S58), the process proceeds to S62 and S77. At this time, the maximum protruding area D on each side stored in the first protruding area memory 93D is used as the protruding area at each end.

  In addition, when the control unit 90 determines in S57 that there is no rib in the left largest protrusion area D stored in the second protrusion area memory 93E (NO in S57), the second protrusion area in S72. When it is determined that there is no rib in the maximum protrusion area D on the right side stored in the memory 93E (S72), the maximum protrusion area D on each side stored in the first protrusion area memory 93D is used.

  In S59, when the control unit 90 determines that the rib 81 is present in the minimum left protruding area D0 stored in the second protruding area memory 93E (NO in S59), the dirt flag memory is stored. Referring to 93G, if OFF is stored in dirt flag memory 93G (NO in S58), ON is stored in dirt flag memory 93G (S60), and ON is stored in dirt flag memory 93G (S60). YES in S58), the process proceeds to S62. At this time, the maximum protrusion area D stored in the first protrusion area memory 93D is used as the left protrusion area.

  In S74, if the control unit 90 determines that there is no rib 81 in the minimum protrusion region D0 on the right side stored in the second protrusion region memory 93E (NO in S74), the control unit 90 The right protrusion area D1 (an example of the ninth area of the present invention) is reset until the right protrusion area can avoid the rib 81, and the reset protrusion area D1 is reset to the first protrusion area memory. 93D (S76, an example of the ninth area setting means of the present invention).

<Modification>
In the present embodiment, in S55 of the flowchart shown in FIG. 12 and S70 of the flowchart shown in FIG. 13, the sheet is conveyed by 0.1 inch from the current paper side edge position and the currently determined paper P1. In this case, it is assumed that the estimated positions of the both sides of the sheet P1 are shifted, but the present invention is not limited to this. For example, in S55, it is determined whether or not the current paper left edge position determined this time is deviated from the previous paper left edge position determined last time. In S70, it is determined whether or not the current right edge position of the paper determined this time is shifted from the previous right edge position of the previous paper determined last time.

  In the present embodiment, the center of the sheet P in the left-right direction 9 passes through the center of the platen 34 in the left-right direction, but the present invention is not limited to this. For example, the left end of the paper P may pass along the left end of the platen 34, or the right end of the paper P may pass along the right end of the platen 34.

  In the present embodiment, borderless printing is not performed on the leading edge and the trailing edge of the paper P (both side edges in the front-rear direction 8). However, the present invention is not limited to this. Needless to say, printing is done.

  In the present embodiment, the recording head 30 that ejects ink is provided on the carriage 31 that is scanned in the left-right direction 9, but is not limited thereto. For example, a line head in which the size of the recording head 30 in the left-right direction 9 is larger than the left-right direction 9 of the largest paper P that can be printed by the multifunction machine 10 may be used.

  In the present embodiment, the media sensor 52 that determines both side edges of the paper is provided in the carriage 31 that is scanned in the left-right direction 9, but is not limited thereto. For example, both side edges of the paper may be determined using a line sensor larger than the left-right direction 9 of the largest paper P that can be printed by the multifunction machine 10.

  In the present embodiment, when changing the protrusion area, it is realized by changing the range of addresses to be read, but this is not restrictive. For example, when the address range to be read is left as it is and the protrusion area is desired to be reduced, a mask process may be performed in which all the pixel data stored in each block is rewritten without discharging. .

  In the present embodiment, in S9 and S54, the same maximum protrusion area D is set at both ends of the paper P. However, the present invention is not limited to this, for example, on the left side of the paper P and the right side of the paper P. The maximum protrusion area D may be set differently.

  In this embodiment, when determining whether or not the rib 81 is present in the maximum protrusion area D in S20, the encoder count value from the ink discharge start position outside the paper P to the left end of the paper P is Although it is determined whether or not the encoder count value of the rib 81 stored in the ROM 92 exists, the present invention is not limited to this. For example, the distance L1 between the encoder count value on the left side of the paper P and the encoder count value at the left ink discharge start position, and the distance L2 between the encoder count value on the left side of the paper P and the encoder count value up to the rib 81 When L1 <L2, it is determined YES in S20, and when L1> L2, NO is determined in S20. The same applies to S21, S24, S25, 57, S59, S72, and S74, and it may be determined whether or not there is a rib 81 in each protruding region by comparing the distances.

<Operational effects of this embodiment>
According to the present embodiment, when performing borderless printing in which no margin is provided at both side edges of the paper P, the maximum protrusion area D set based on the positions of the both edges of the paper P determined by the media sensor 52. If the rib 81 is present, the protrusion area is reset to the protrusion area D1 that can avoid the rib 81. Then, the control unit 90 controls the carriage 31 and the recording head 30 to discharge ink into an ink discharge region constituted by the protruding region D1 that can avoid the rib 81 and the width in the left-right direction 9 of the paper. As a result, it is possible to suppress the ink from being ejected to the rib 81 on which the lower surface of the paper P is supported, so that the show-through to the subsequent paper can be reduced.

  According to the present embodiment, the protrusion area D1 is smaller than the maximum protrusion area D, and is variably set in a range equal to or greater than the minimum protrusion area D0. Therefore, the size of the protruding region set based on the both end positions determined by the media sensor 52 can guarantee the image quality of borderless printing, and ink is ejected to the rib 81 on which the lower surface of the paper P is supported. Therefore, it is possible to reduce the show-through on the subsequent paper.

  According to the present embodiment, when the rib 81 is within the minimum protrusion area D0, the display unit 18 displays that the rib 81 is dirty. Further, the fact that the rib 81 is soiled is displayed until the cover 12 is opened, and the borderless printing on the subsequent paper P is not started. As a result, the user can confirm that the rib 81 is soiled via the display unit 18, and the borderless printing is not resumed until the cover 12 is opened, so that the ink discharged on the rib 81 can be cleaned. It is possible to reduce the show-through on the subsequent paper.

  According to this embodiment, when the paper P is conveyed by a predetermined distance, the media sensor 52 determines the positions of both side edges of the paper. Then, the transport amount for the next time is transported from the currently determined position of the sheet P from the both end positions of the sheet P at the time of the previous determination and the both end positions of the sheet P at the present determination. The position of both side edges of the paper P when being printed is calculated. Next, the both-side edge positions of the paper P when the paper is determined last time or the both-side edge positions of the paper P when the next determined conveyance amount is conveyed, and the both-side edges of the paper P when currently determined If the position is different, the protruding area at the both end positions of the sheet P when the next transport amount is transported is used to determine the position at the both end positions of the sheet P as currently determined. Set the overhang area. Therefore, when the sheet P is conveyed in a skewed state, the positions of both ends of the sheet P change every time the sheet P is conveyed, and even if the size of the protruding area changes, the protruding area can be reduced, When there is a possibility of being dirty, the notification is made, and the show-through to the subsequent paper can be suppressed.

12 Cover 12
DESCRIPTION OF SYMBOLS 16 Operation panel 19 Opening / closing sensor 20 Paper feed tray 24 Recording part 30 Recording head 31 Carriage 34 Platen 47 Conveyance roller 49 Paper discharge roller 52 Media sensor 68 Rotary encoder 69 Linear encoder 81 Rib 83 Inclined surface 90 Control part 101 Guide plate

Claims (5)

Conveying means for conveying the recording medium in the conveying direction;
A carriage having a recording head for ejecting ink on a recording medium to be conveyed, and a carriage that can reciprocate in a main scanning direction orthogonal to the conveying direction;
A platen that supports the lower surface of the recording medium to be transported and extends along the transport direction, and includes a plurality of protrusions disposed in the main scanning direction, and is disposed at a position facing the lower surface of the recording head;
Driving the optical means for emitting light to the recording medium to be conveyed or the platen and receiving the reflected light, and the main scanning direction of the recording medium to be conveyed from the light received by the optical means Both end determining means for determining the first end positions of
The determined region between the first end positions, one region extending from one end of the first end positions to the outside of the recording medium in the main scanning direction, and the other end of the first end positions An ejection area setting means for setting an area for ejecting ink from the other area extending from the recording medium to the outside of the recording medium in the main scanning direction;
Control means for controlling the recording head and the carriage so as to eject ink in an area for ejecting ink set by the ejection area setting means;
Storage means capable of storing the first information;
An informing means for informing when the first information is stored in the storage means;
First area setting means for setting a first area extending by a first distance from one end of the first both end positions to the outside of the recording medium in the main scanning direction;
A second area setting means for setting a second area extending by a second distance from the other end of the first end positions to the outside of the recording medium in the main scanning direction;
A projection that extends from one end of the first both end positions to the outside of the recording medium in the main scanning direction, is smaller than the first distance and is located outside the recording medium and is closest to the one end. A third region setting means for setting the third region within a third distance to the section;
A projection that extends from the other end of the first end position to the outside of the recording medium in the main scanning direction, is smaller than the second distance and is located outside the recording medium and is closest to the other end. A fourth area setting means for setting the fourth area within a fourth distance to the section;
First determination means for determining whether or not the protrusion is in the first region at one end of the first both end positions;
Second determination means for determining whether or not the protrusion is in the first region at the other end of the first both end positions;
Third determination means for determining whether or not the protrusion is in the fifth region at the one end of the first both-end positions;
An image recording apparatus comprising: a fourth determination unit configured to determine whether or not the protrusion is in the fifth region at the other end of the first both end positions ;
Further, the third area and the fourth area extend from one end and the other end of the first both end positions to the outside of the recording medium, and are equal to or less than the third distance and the fourth distance. A size equal to or greater than a fifth region extending a fifth distance corresponding to the resolution of the both end determination means from the medium;
The third area setting means sets the third area at a maximum distance within the third distance among values obtained by multiplying the fifth distance by an integer.
The fourth area setting means sets the fourth area as a maximum distance within the fourth distance among values obtained by multiplying the fifth distance by an integer.
The discharge area setting means includes
When it is determined that there is no projection in the first region at one end of the first both end positions, the region used for the one side region is set as the first region ,
When the protrusion is determined that there is no prior Symbol the second region of the other end of the first end positions, set the area used in the region of the other side in the second region,
It is determined that the protrusion is in the first region at one end of the first both end positions, and the protrusion is in the fifth region at one end of the first both end positions. When it is determined that there is not, the region used for the one side region is set as the third region, and it is determined that the protrusion is in the fifth region at one end of the first both end positions. The area used for the one side area is set as the first area,
It is determined that the protrusion is in the second region at the other end of the first both ends, and the protrusion is in the fifth region at the other end of the first both ends. If it is determined that there is not, the region used for the other region is set as the fourth region, and it is determined that the protrusion is in the fifth region at the other end of the first both end positions. The second area is set as the area used for the other area,
The storage means
An image recording apparatus that stores the first information when it is determined that there is a protrusion in the fifth region at one end or the other end of the first both end positions . The both-end determining means determines the first both-end positions each time the recording medium is conveyed by a predetermined amount larger than a single conveyance amount,
The one-time conveyance from the position of the recording medium determined this time based on the first both-end positions of the recording medium determined this time by the both-end determination means and the second both-end positions of the recording medium determined previously. A calculating means for calculating the third end positions of the recording medium at a position where the amount is conveyed in the conveying direction;
The ejection area setting means includes a calculated area between the third both end positions, a first area extending from one end of the third both end positions to the outside of the recording medium in the main scanning direction, and the first A region where ink is ejected from the other end of the three end positions extending to the outside of the recording medium in the main scanning direction;
A sixth area setting means for setting a sixth area extending from the one end of the third both end positions to the outside of the recording medium in the main scanning direction by the first distance;
A seventh area setting means for setting a seventh area extending from the other end of the third both end positions to the outside of the recording medium in the main scanning direction by the second distance;
A protrusion extending from one end of the third both end positions to the outside of the recording medium in the main scanning direction, being smaller than the first distance and positioned outside the recording medium and closest to the one end An eighth area setting means for setting the eighth area within the third distance to the section;
A projection that extends from the other end of the third both end positions to the outside of the recording medium in the main scanning direction, is smaller than the second distance and is located outside the recording medium and is closest to the other end. A ninth area setting means for setting the ninth area within the fourth distance to the section;
Fifth determination means for determining whether or not the first end position is different from the second end position or the third end position;
The sixth region of the region on one side of the third end positions when the fifth determination means determines that the first end positions are different from the second end positions or the third end positions. Sixth determination means for determining whether or not the protrusion is present in the interior;
When the fifth determination means determines that the first end position is different from the second end position or the third end position, the seventh area of the area on the other side of the third end position And a seventh judging means for judging whether or not the protruding portion is in the inside,
Further, the discharge area setting means includes
When it is determined that there is no protrusion in the sixth region of the one side region of the third both end positions, the region used for the one side region is set as the sixth region, and the third region When it is determined that the protrusion is in the sixth region of the one side region of both end positions, the region used for the one side region is set as the eighth region,
When it is determined that the projection is not present in the seventh region of the other region on the other side of the third end positions, the region used for the other region is set as the seventh region, and the third region The region used for the other side region is set as the ninth region when it is determined that the projection is in the seventh region of the other side region at both end positions. 2. The image recording apparatus according to 1. The eighth area and the ninth area extend from one end and the other end of the third both end positions to the outside of the recording medium, and are equal to or less than the third distance and the fourth distance. The size of the tenth region or more extending from the fifth distance corresponding to the resolution of the both end determination means,
The eighth area setting means sets the eighth area at a maximum distance within the third distance among values obtained by multiplying the fifth distance by an integer .
The image according to claim 2 , wherein the ninth area setting means sets the ninth area at a maximum distance within the fourth distance among values obtained by multiplying the fifth distance by an integer. Recording device. Eighth judgment means for judging the whether the protrusion is before Symbol the tenth region of one end of the third end positions,
And 9th determination means for determining whether or not the protrusion is in the 10th region at the other end of the third both end positions,
The discharge area setting means includes
In the case where it is determined that the protrusion is in the sixth region of the region on one side of the third both end positions, the protrusion is in the tenth region on one end of the third end positions. When it is determined that there is not, the region used for the one side region is set as the eighth region, and it is determined that the protrusion is in the tenth region at one end of the third both end positions. If so, the region used for the one side region is set as the sixth region,
It is determined that the protrusion is in the seventh region of the other side region of the third both end positions, and the protrusion is in the tenth region of the other end of the third both end positions. When it is determined that there is no area, the area used for the other area is set as the ninth area, and it is determined that the protrusion is in the tenth area at the other end of the third both end positions. If so, the region used for the other region is set as the seventh region,
Before Kiki憶means,
If it is determined that there is the protrusion in the third across one end position or the other of the first 10 in the region of the end, according to claim 3, characterized in memorize to Rukoto the first information Image recording device. A cover that covers the platen and can be opened and closed;
Detecting means for detecting opening and closing of the cover,
The notification means, according to claim 1, characterized in that stopping the notification condition that the printing of one page of the recording medium is a broadcast starts When finished, the opening and closing of the cover is detected by said detecting means 5. The image recording device according to any one of 4 to 4 .

Images