JP2005262822A - Capping device and liquid droplet discharging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capping device which can efficiently recover the ink discharging performance of nozzle openings for discharging different inks, and to provide a liquid droplet discharging apparatus equipped with this capping device. <P>SOLUTION: The capping device is equipped with a cap member 30 for covering a plurality of nozzle arrays 24a-24f each with a plurality of the nozzle openings formed at a nozzle plate 25, and a suction pump 40 for generating a negative pressure at an internal space (sealed space) 45 surrounded by the cap member 30 and the nozzle plate 25. A groove 34 is formed at the cap member 30 as a recess opposed to one of the plurality of nozzle arrays 24a-24f in a state that the cap member 30 covers the plurality of nozzle arrays 24a-24f. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a capping device for covering a droplet ejection head that ejects droplets, and a droplet ejection device including the capping device.

  An example of a conventional droplet discharge device is an ink jet printer that forms an image on a recording medium by discharging ink droplets onto a recording medium such as paper. Inkjet printers are used for various types of printing including color printing because the noise during printing is relatively low, and fine dots can be ejected onto paper at a high density. Yes.

  This type of ink jet printer includes a print head mounted on a carriage that reciprocates in the width direction of the recording medium, and a recording medium transport mechanism that sends the recording medium in a direction orthogonal to the moving direction of the carriage.

  The print head has a pressure chamber that pressurizes ink, and a nozzle opening that communicates with the pressure chamber and ejects the pressurized ink as ink droplets to the outside of the print head. For example, the ink jet printer drives a carriage and a recording medium transport mechanism in response to print data received from a host computer. Then, the print head pressurizes the ink in the pressurizing chamber according to a predetermined drive pulse, thereby ejecting ink droplets from the nozzle opening toward the recording medium. The ink droplets ejected from the nozzle openings are landed and fixed on the recording medium, thereby forming an image on the recording medium.

  In an inkjet printer capable of color printing, the print head has a pressure chamber and a nozzle opening for each color, and color printing is performed by ejecting ink droplets of colors according to print data from each nozzle opening. Execute.

  In an ink jet printer, conditions such as an increase in ink viscosity, solidification of ink, adhesion of dust, mixing of bubbles, and the like are likely to occur in the nozzle opening of the print head and inside thereof. In the ink jet printer, in order to avoid this deterioration in print quality, the capping device is used to cover the print head and the suction pump is used to suck the inside of the capping device, thereby sucking out the ink in the print head including the nozzle openings. A so-called capping suction cleaning operation is performed.

  In general, in an ink jet printer, by performing this capping, ink from an ink tank or an ink cartridge is smoothly filled into the pressurizing chamber, the deteriorated ink in the nozzle opening and the pressurizing chamber is sucked and discharged, and the ink in the pressurizing chamber is discharged. The internal bubbles are removed and the print head is always kept in a good state (see, for example, Patent Document 1).

  In the above-described capping, a method is generally used in which a suction hole for suction is provided at one place on the inner surface side of the capping device, and ink in the print head is sucked out by sucking ink from the suction hole.

  In a method in which a suction hole for suction is provided at one place on the inner surface side of the capping device, and suction is performed using a suction pump through this suction hole, the ink suction force varies within the capping device depending on the position of the suction hole. May occur. As described above, when the suction force varies in the capping device, the ink can be sufficiently sucked out from the nozzle opening arranged in the region where the suction force is strong, but the nozzle arranged in the region where the suction force is weak. There is a possibility that the ink may not be sufficiently sucked out from the opening, and the printing accuracy may vary from nozzle opening to nozzle opening.

In order to solve this problem, the capping device is configured such that the dimensions of the capping device are set so as to cover a range longer than the length of the nozzle row comprising a plurality of nozzle openings, and all the nozzle rows are sucked evenly. Has also been proposed (see, for example, Patent Document 2).
Japanese Patent Laid-Open No. 2003-341077 JP 2003-175617 A

  In general, in the case of a color print head that discharges a plurality of types of ink, the ink characteristics are different for each color, and therefore the optimum suction force during cleaning may be different for each ink. In particular, in the case of pigment-based ink, the drying property and viscosity of the ink may differ greatly depending on the color, and ink clogging occurs in the nozzle openings that eject ink that is easy to dry or highly viscous. It's easy to do. If uniform capping is performed on these nozzle openings, the degree of improvement in the state of the nozzle openings and the pressure chambers, that is, the recoverability of ink ejection properties may vary for each color. In this way, when printing is performed using a print head having a nozzle array in which the ink discharge performance is not sufficiently improved for each color, a desired color can be obtained because an expected amount of ink droplets are not discharged depending on the color. As a result, there is a problem that a situation occurs in which the print quality is deteriorated.

  In order to solve this problem, it is conceivable to repeat the ink suction until the ink discharge performance of the nozzle openings that discharge ink that tends to be clogged is restored to the same level as the other nozzle openings. However, if the ink suction operation is repeated many times in order to improve the ink discharge performance of such poorly recoverable nozzle openings, the ink is also sucked from the already recovered nozzle openings, so it is used for printing. The amount of ink consumed unnecessarily increases.

  The present invention has been made in view of the above, and provides a capping device capable of efficiently recovering the ink discharge performance of nozzle openings for discharging different inks, and a droplet discharge device including the capping device. The purpose is to provide.

The object of the present invention is achieved by the following configurations.
(1) a cap member that covers a plurality of nozzle rows each formed of a plurality of nozzle openings formed on the droplet discharge member;
A pump for generating a negative pressure in a sealed space surrounded by the cap member and the droplet discharge member,
The capping device, wherein the cap member is formed with a recess facing the one of the plurality of nozzle rows in a state of covering the nozzle row.
(2) The capping device according to (1), wherein an opening communicating with the pump is formed in the recess.
(3) The concave portion is provided at a position facing a nozzle row that ejects droplets that are more likely to be clogged than droplets ejected from other nozzle rows (1) or ( 2) The capping device described above.

(4) having a plurality of recesses facing each one of the plurality of nozzle rows,
The capping device according to any one of (1) to (3), wherein the number of the plurality of recesses is smaller than the number of the nozzle rows.
(5) The capping device according to any one of (1) to (4), wherein the recess is provided with a plurality of openings communicating with the pump.
(6) A droplet absorbing member that absorbs the droplet is disposed on the cap member,
6. The capping device according to any one of (1) to (5), wherein a density of a droplet absorbing member in a region sandwiched between one of the nozzle rows and the concave portion is lower than that of other regions. .
(7) A droplet absorbing member that absorbs the droplet is disposed on the cap member,
The capping according to any one of (1) to (5), wherein a thickness of the droplet absorbing member in a region sandwiched between one of the nozzle rows and the recess is thinner than the other region. apparatus.
(8) a droplet discharge member that discharges droplets onto the object;
A carriage for moving the droplet discharge member in a first direction;
A transport mechanism for transporting the object in a second direction orthogonal to the first direction;
A capping device for improving the droplet discharge property of the droplet discharge member,
The droplet discharge member has a droplet discharge member in which a plurality of nozzle rows each having a plurality of nozzle openings for discharging droplets are formed,
The capping member is
A cap member covering the plurality of nozzle rows;
A pump that generates a negative pressure in a space surrounded by the cap member and the droplet discharge member,
The droplet discharge device according to claim 1, wherein the cap member is formed with a recess facing the one of the plurality of nozzle rows in a state of covering the nozzle rows.
(9) The droplet discharge device according to (8), wherein an opening communicating with the pump is formed in the recess.
(10) One of the plurality of nozzle rows ejects a droplet that is more likely to be clogged than a droplet ejected from another nozzle row. (8) or (9) Droplet discharge device.
(11) having a plurality of recesses respectively facing any one of the plurality of nozzle rows;
The droplet discharge device according to any one of (8) to (10), wherein the number of the plurality of recesses is smaller than the number of the nozzle rows.
(12) The droplet discharge device according to any one of (8) to (11), wherein the recess is provided with a plurality of openings communicating with the pump.
(13) A droplet absorbing member that absorbs the droplet is disposed on the cap member,
The droplet according to any one of (8) to (12), wherein a density of a droplet absorbing member in a region sandwiched between one of the nozzle rows and the concave portion is lower than that of another region. Discharge device.
(14) A droplet absorbing member that absorbs the droplet is disposed on the cap member,
13. The liquid according to any one of (8) to (12), wherein a thickness of the droplet absorbing member in a region sandwiched between one of the nozzle rows and the concave portion is thinner than that in the other region. Drop ejection device.

  According to the present invention, since the concave portion is formed at a position facing one of the plurality of nozzle rows, compared with a case where the suction force from the nozzle row facing the concave portion is sucked from another nozzle row. It can be increased relatively. This makes it possible to positively execute ink suction from the nozzle row located at the position facing the concave portion, and to make it easier for the ink ejection properties of this nozzle row to recover than the other nozzle rows. Therefore, even when one of the plurality of nozzle rows discharges ink that is more likely to be clogged than the other nozzle rows, ink can be sucked with a stronger suction force than the other nozzle rows. Therefore, it is possible to enhance the cleaning effect by one suction, and it is possible to reduce the number of times of ink suction with respect to the nozzle row that is likely to be clogged. Thereby, the amount of ink sucked by the capping operation can be reduced, and the ink in the ink cartridge can be prolonged.

  Hereinafter, embodiments of a capping device according to the present invention and a droplet discharge device including the capping device will be described with reference to the drawings. In the following description, an inkjet printer will be described as an example of a droplet discharge device.

  FIG. 1 is a partial external perspective view of the ink jet printer of the present embodiment, FIG. 2 is a schematic cross-sectional view of a print head and an ink cartridge of the ink jet printer, and FIG. 3 is a plan view of the print head.

  The ink jet printer 1 is an ink jet type image recording apparatus, and a recording medium transport direction in which a recording medium S such as paper disposed on a platen (not shown) is forwarded from the rear to the front of the housing 1 a via a transport roller 12. The apparatus forms an image by landing ink on the recording medium S while being conveyed.

  Both ends of a rod-shaped guide rail 13 are fixed to both side walls 11a and 11b of the housing 11, respectively. The guide rail 13 is arranged in a direction (recording medium width direction) whose longitudinal direction is orthogonal to the recording medium conveyance direction. The guide rail 13 is a guide member that regulates the moving direction of the carriage 14.

  The carriage 14 is slidably attached along the guide rail 13 and is fixed to a driving belt 15 driven via a motor 16. The carriage 14 reciprocates along the longitudinal direction of the guide rail together with the drive belt 15 according to the rotation of the motor 16.

An ink cartridge 17 is detachably attached to the upper surface side of the carriage 14. The ink cartridge 17 is an ink tank filled with ink corresponding to a plurality of colors.
A print head 20 for ejecting ink in the ink cartridge 17 toward the recording medium S is attached to the lower surface side of the carriage 14. In the inkjet printer 10 of this embodiment, printing is performed over a predetermined area or the entire surface of the recording medium by conveying the recording medium in the recording medium conveying direction via the conveying roller 12 while reciprocating the carriage 14 in the recording medium width direction. By ejecting ink from the head 20, an image is recorded on the recording medium.

  As shown in FIG. 2, the ink cartridge 17 of this embodiment includes a color ink cartridge 17a and a black ink cartridge 17b.

  The color ink cartridge 17a is formed with ink chambers 18a, 18b, 18c, 18d, and 18e for storing five color inks used for color printing, and each of the ink chambers 18a to 18e is different. Filled with different types of ink. For example, the ink filled in each of the ink chambers 18a to 18e is CY (cyan) ink in the ink chamber 18a, M (magenta) ink in the ink chamber 18b, and Y (yellow) ink in the ink chamber 18c. The ink chamber 18d is filled with LCY (light magenta) ink, and the ink chamber 18e is filled with LM (light magenta) ink.

  The black ink cartridge 17b is formed with an ink chamber 18f for storing black ink used for monochrome printing or color printing. In the present embodiment, the color ink cartridge 17a and the black ink cartridge 17b are separated from each other in consideration of the difference in the consumption amounts of the black ink and the color ink, and can be independently attached and detached.

  FIG. 2 shows a state immediately before the color ink cartridge 17a and the black ink cartridge 17b are attached to the print head 20, but when the cartridges 17a and 17b are attached to the print head 20, the upper surface of the head 20 is shown. The ink needles 21a, 21b, 21c, 21d, 21e, and 21f arranged on the side are inserted into the corresponding ink chambers 18a to 18f of the color ink cartridge 17a and the black ink cartridge 17b, and the ink chambers 18a to 18f. Each ink inside is injected into the print head 20 through the flow path in these ink needles 21a to 21f.

  The inks sent from the ink needles 21a to 21f into the print head 20 are pressurized chambers 23a, 23b, and 23c via ink paths 22a, 22b, 22c, 22d, 22e, and 22f communicating with the ink needles 21a to 21f. , 23d, 23e, and 23f.

  The pressurizing chambers 23a to 23f are configured such that the internal pressure is variable via a piezo element (not shown), and a plurality of nozzles communicating with the pressurizing chambers 23a to 23f according to pressure fluctuations due to driving of the piezo element. Ink droplets are ejected downward from the nozzle opening rows 24a, 24b, 24c, 24d, 24e, and 24f. These nozzle opening rows 24a to 24f are formed in a nozzle plate 25 that is arranged closest to the recording medium of the print head 20.

  As shown in FIG. 3, the nozzle openings of the nozzle rows 24 a to 24 f are arranged so as to form a row in a direction perpendicular to the conveyance direction of the image recording medium, that is, the movement direction of the carriage 14 and the print head 20. . Specifically, in the present embodiment, each of the nozzle rows 24a to 24f has 180 nozzle openings (only 17 are schematically shown in FIG. 3), and ink droplets are simultaneously discharged from each nozzle opening at the maximum. By discharging, it is possible to simultaneously perform image recording with a width in the recording medium conveyance direction.

Next, returning to FIG.
At one end of the carriage 14 in the moving direction, a cap member 30 for capping the print head 20, a suction pump 40 for sucking the inside of the cap member 30 to make negative pressure, and a nozzle plate 25 of the print head 20 A wiper member 50 that wipes ink and dust adhering to the nozzle plate 25 by rubbing the surface is disposed. In the present embodiment, the cap member 30 and the suction pump 40 constitute a capping device.

  The cap member 30 is a device for covering the print head 20 at a predetermined timing such as when the power is turned off, when waiting, or when printing failure occurs. The cap member 30 covers the print head 20 and is sucked by the suction pump 40 to suck out the ink in the print head 20 from the nozzle rows 24a to 24f, and from the ink cartridges 17a and 17b to the pressurizing chamber 23a. In addition to smoothly supplying ink to 23 f, the inside of the print head 20 is always in a good state by sucking and discharging the deteriorated ink in the nozzle opening and the pressure chamber, removing bubbles in the ink in the pressure chamber, etc. Configured to keep on.

  4 is an exploded perspective view showing the configuration of the cap member 30, FIG. 5 is a top view of the cap body 31, and FIG. 6 is a cross-sectional view of the cap member 30. As shown in FIG.

  As shown in FIGS. 4 to 6, the cap member 30 includes a cap body 31 having a bottom portion 31 a having a substantially rectangular shape and side walls 31 b erected integrally from four sides of the bottom portion 31 a. On the inner surface side of the side wall 31b of the cap body 31, a stepped portion 31c having a rectangular shape when viewed from above is formed along the inner surface of the side wall 31b. An annular sealing member 32 is fitted and fixed to the step 31c by bonding or the like, and the upper end of the annular sealing member 32 is provided so as to protrude above the upper end of the side wall 31b. .

  When the cap member 30 is pressed against the surface of the nozzle plate 25 of the print head 20, the sealing member 32 has a nozzle so as to close the opening 30 a formed along the upper end on the inner peripheral surface side of the sealing member 32. A member that is in close contact with the plate 25. The sealing member 32 is configured to maintain the airtightness between the inside and the outside of the cap member 30 while being in close contact with the nozzle plate 25. The sealing member 32 is preferably a member that does not damage the nozzle plate 25 and is preferably made of a material that can maintain good internal airtightness. Examples of such a sealing member 32 include elastic members such as rubber. Is done.

  On the bottom 31a of the cap body 31, an ink absorbing member 33 formed from a nonwoven fabric made of dry pulp or the like is disposed. The ink absorbing member 33 absorbs the sucked ink to prevent the ink plate from being bounced back to the nozzle plate 25, and the ink absorbing member 33 caps the nozzle plate 25 with the cap member 30 by the ink absorbed by the ink absorbing member 33. The inside of the member 30 is kept wet, and the nozzle openings of the nozzle rows 24a to 24f and the inside thereof are prevented from being dried. The ink absorbing member 33 preferably has high air and ink flowability and high ink retention, and examples thereof include Kinocloth # 02-47-03 (trade name, manufactured by Oji Kinocross Co., Ltd.).

  Further, a groove 34 is formed on the bottom portion 31a of the cap body 31 on the side facing the ink absorbing member 33. The upper surface side and the lower surface side of the suction bottom portion 31a are communicated with one end portion of the groove 34. A suction hole 35 is formed. An attachment portion 36 is provided on the back side of the bottom portion 31 a of the cap body 31 so as to correspond to the suction hole 35, and the suction tube 41 is connected to the attachment portion 36.

  The suction tube 41 is connected to the suction pump 40. In the suction pump 40, the cap member 30 is driven by a driving mechanism (not shown), and the cap member 30 is surrounded by the cap member 30 and the nozzle plate 25 in a state where the sealing member 32 of the cap member 30 is in close contact with the nozzle plate 25. By suctioning from the internal space 45 (sealing space) through the suction tube 41 and the suction hole 35, the internal space 45 is brought into a negative pressure state. When the internal space 45 is in a negative pressure state, ink is sucked from the nozzle openings of the nozzle rows 24a to 24f of the nozzle plate 25, and ink is supplied from the ink cartridges 17a and 17b to the pressurizing chambers 23a to 23f and the nozzles. The ink is supplied to the opening, and the ink in the pressurizing chambers 23a to 23f and each nozzle opening is exchanged. At the time of this suction, ink with increased viscosity in the pressurizing chambers 23a to 23f and the nozzle openings, fixed ink, dust that has entered the interior, and the like are also discharged at the same time, and ink in a good state is discharged into the pressurizing chambers 23a to 23f and Supplied into each nozzle opening. Ink sucked by the suction pump 40 is discharged to the ink reservoir 42.

  FIG. 7 is a diagram illustrating a relative positional relationship between the print head 20 and the cap member 30, and FIG. 8 is a cross-sectional view illustrating a state of ink suction using the cap member 30.

  As shown in FIG. 7, the longitudinal direction of the groove 34 is formed in a direction parallel to the nozzle arrangement direction of the nozzle rows 24 a to 24 f. Further, the groove 34 is formed so as to face the nozzle row 24 b and to be positioned directly below the nozzle row 24 b in a state where the cap member 30 is pressed against the nozzle plate 25 of the print head 20.

  As shown in FIG. 7, in a state where the ink absorbing member 33 is disposed in the cap body 31, the ink absorbing member 33 does not enter the groove 34 (only a part even when entering), and the internal space 45. The air inside and the sucked ink are in a state where they can easily flow in the longitudinal direction of the groove 34 by driving the suction pump 40. When air or ink easily flows in the longitudinal direction of the groove 34, as indicated by an arrow in FIG. 8, the suction force from the nozzle row 24 b disposed opposite to the groove 34 to the groove 34 causes other nozzle rows to flow. It becomes relatively larger than the case where ink is sucked downward from 24a, 24c to 24f.

  That is, in this embodiment, the groove 34 is provided in the cap body 31 so as to face the nozzle row 24b, so that the suction force from the nozzle row 24b is sucked from the other nozzle rows 24a, 24c to 24f. The ink ejection performance of the nozzle array 24b is more easily recovered than the other nozzle arrays 24a and 24c to 24f by actively executing ink suction. In such a configuration, when it is desired to actively perform suction from a specific nozzle row, for example, when a nozzle row that ejects ink that is likely to be clogged is sucked with a stronger suction force than other nozzle rows. It is effective when used for.

  In this embodiment, the ink ejected from the nozzle row 24b is magenta ink. However, particularly when this magenta ink is composed of a pigment-based material, clogging occurs as compared with inks of other colors. It's easy to do. In such a state, if ink suction is performed with the same suction force as that of the other nozzle rows, a situation may be considered in which the ink discharge performance is not sufficiently recovered by the nozzle row 24b that discharges the magenta ink. In order to improve the ink discharge performance of such a poorly recoverable nozzle row, it is necessary to repeat the ink suction operation many times. However, when such ink suction is performed, the already recovered nozzle row 24a. , 24c to 24f, the ink is sucked from the nozzle rows 24a and 24c to 24f.

  However, as in this embodiment, the groove 34 is formed in the cap body 31 corresponding to the nozzle row 24b, and the nozzle row 24b that discharges the magenta ink is actively sucked, so that the number of suctions can be reduced. The ink discharge performance of the row 24b can be recovered to the same level as the other nozzle rows 24a and 24c to 24f.

  In the present embodiment, the ink sucked to the bottom surface of the groove 34, particularly the corners of the four corners, may remain without being discharged from the suction hole 35. Such ink contributes to the improvement of moisture retention inside the cap body 31. In particular, a groove 34 is provided facing the nozzle row that discharges the ink with the highest drying property, and when ink remains in the groove 34, it contributes to moisture retention of the nozzle row that discharges the ink with high drying property. In addition, the drying of the ink can be delayed.

  As described above, the capping device of this embodiment includes the cap member 30 that covers the plurality of nozzle rows 24 a to 24 f each having a plurality of nozzle openings formed in the nozzle plate 25, and the cap member 30 and the nozzle plate 25. And a suction pump 40 that generates a negative pressure in the enclosed internal space (sealed space) 45. The cap member 30 is formed with a groove 34 as a recess facing one of the plurality of nozzle rows 24a to 24f in a state where the cap member 30 covers the plurality of nozzle rows 24a to 24f. Yes.

  According to this embodiment, since the groove 34 is formed at a position facing one of the plurality of nozzle arrays 24a to 24f, ink suction is positively performed from the nozzle array located at the position facing the groove 34. In addition, the ink ejection property of this nozzle row is configured to be more easily recovered than other nozzle rows. Therefore, even when one of the plurality of nozzle rows 24a to 24f ejects ink that is more likely to be clogged than the other nozzle rows, ink suction is performed with a stronger suction force than the other nozzle rows. Is possible. Therefore, the cleaning effect by one suction can be enhanced, and the number of ink suctions to the nozzle rows that are likely to be clogged can be reduced. Thereby, the amount of ink sucked by the capping operation can be reduced, and the ink in the ink cartridge can be prolonged.

  In the present embodiment, the groove 34 is provided at a position facing one nozzle row 24b. However, the present invention is not limited to this, and a plurality of recesses facing a plurality of nozzle rows are provided. It may be configured. In this case, it is possible to provide grooves so as to face all the nozzle rows, but by making the number of concave portions smaller than the number of nozzle rows, the concave portions are formed more than the nozzle rows where no concave portions are provided. The ink suction force from the provided nozzle row can be increased. Therefore, when there are two or more types of ink that are more likely to be clogged than other inks, a recess is provided opposite to the nozzle row that discharges each ink, and a suction hole is provided in each recess. Alternatively, ink suction may be performed.

  In the embodiment described above, the suction hole 35 is provided at one end of the groove 34, but the present invention is not limited to this. For example, like the cap member 30A shown in FIG. 9, the suction hole 35A may be formed in the central portion in the longitudinal direction of the groove 34 formed in the cap body 31A. In the case of the cap member 30A, the suction hole 35A is provided at a symmetrical position with respect to the groove 34, so that variation in suction force in the longitudinal direction of the groove 34 is reduced as compared with the cap member 30 shown in FIG. Is possible.

  Further, as in the cap member 30B shown in FIG. 10, the suction holes 35B, 35C, and 35D are formed in a total of three locations in the longitudinal center portion of the groove 34 formed in the cap body 31B and both ends thereof. Also good. In the case of the cap member 30B, since the plurality of suction holes 35B to 35D are arranged so as to be symmetric with respect to the groove 34, compared to the cap member 30 shown in FIG. 5 and the cap member 30A shown in FIG. It is possible to further reduce the variation in the suction force in the longitudinal direction of the groove 34.

Further, the ink absorbing member 33 described in the above embodiment is not limited to that described in the above embodiment.
For example, like the cap member 30 </ b> C shown in FIG. 11, the density of the ink absorbing member 33 may be changed between the region 33 b located immediately above the groove 34 and the other region 33 a. In this case, at the time of capping, the density between one of the nozzle rows located immediately above the region 33b and the groove 34 is lower than that of the other regions. Therefore, ink or air is transferred from the nozzle row located immediately above the region 33b to the groove 34. The ink suction force with respect to the nozzle row located directly above the groove 34 is relatively increased, and the ink is more easily absorbed.

  Further, like the cap member 30D shown in FIG. 12, by removing a part of the ink absorbing member on the groove 34 side (lower surface side) of the ink absorbing member 33 located immediately above the groove 34, a removal portion 33c is formed. The thickness of the ink absorbing member 33b located directly above the groove 34 may be reduced. Even in this case, ink or air easily flows from the nozzle row located directly above the groove 34 to the groove 34, and the ink suction force with respect to the nozzle row located directly above the groove 34 is relatively increased. It becomes easy to absorb.

  Similarly, like the cap member 30E shown in FIG. 13, a part of the ink absorbing member on the side opposite to the groove 34 (upper surface side) of the ink absorbing member 33 located immediately above the groove 34 (upper surface side) is removed to remove the removing portion 33d. By forming, the thickness of the ink absorbing member 33b located immediately above the groove 34 may be reduced. Even in this case, ink or air easily flows from the nozzle row located directly above the groove 34 to the groove 34, and the ink suction force with respect to the nozzle row located directly above the groove 34 is relatively increased. It becomes easy to absorb.

  In the present embodiment, as an example of the droplet discharge device, an ink jet printer has been described as an example. However, the present invention is not limited to this. In addition to the ink jet printer, the droplet discharge device includes an electrode material used for forming electrodes such as a device provided with a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an organic EL (Electroluminescence) display, and a surface light emitting display. Examples include an apparatus provided with an ejection head, an apparatus provided with a bioorganic matter ejection head used for biochip production, and an apparatus equipped with a sample ejection head as a precision pipette.

1 is a partial external perspective view of an ink jet printer according to the present invention. 2 is a schematic cross-sectional view of a print head and an ink cartridge of an inkjet printer. FIG. It is a top view of a print head. It is a disassembled perspective view which shows the structure of a cap member. It is a top view of a cap main body. It is sectional drawing of a cap member. It is a figure which shows the relative positional relationship of a print head and a cap member. It is sectional drawing which shows the mode of the ink suction using a cap member. It is a modification of the capping apparatus concerning this invention. It is a modification of the capping apparatus concerning this invention. It is a modification of the capping apparatus concerning this invention. It is a modification of the capping apparatus concerning this invention. It is a modification of the capping apparatus concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inkjet printer 11 Housing | casing 12 Carrying roller 13 Guide rail 14 Carriage 17 Ink cartridge 20 Print head 24a-24f Nozzle row 25 Nozzle plate 30 Cap member 31 Cap main body 32 Sealing member 33 Ink absorption member 34 Groove 35 Suction hole 40 Suction pump

Claims (14)

A cap member covering a plurality of nozzle rows each consisting of a plurality of nozzle openings formed in the droplet discharge member;
A pump for generating a negative pressure in a sealed space surrounded by the cap member and the droplet discharge member,
The capping device, wherein the cap member is formed with a recess facing the one of the plurality of nozzle rows in a state of covering the nozzle row.   The capping device according to claim 1, wherein an opening communicating with the pump is formed in the recess.   3. The capping according to claim 1, wherein the concave portion is provided at a position facing a nozzle row that ejects droplets that are more likely to be clogged than droplets ejected from other nozzle rows. apparatus. Each having a plurality of recesses facing one of the plurality of nozzle rows,
4. The capping device according to claim 1, wherein the number of the plurality of concave portions is smaller than the number of the nozzle rows.   The capping device according to any one of claims 1 to 4, wherein the recess is provided with a plurality of openings communicating with the pump. A droplet absorbing member that absorbs the droplet is disposed on the cap member,
6. The capping device according to claim 1, wherein a density of a droplet absorbing member in a region sandwiched between one of the nozzle rows and the concave portion is lower than that of the other region. A droplet absorbing member that absorbs the droplet is disposed on the cap member,
6. The capping device according to claim 1, wherein a thickness of the droplet absorbing member in a region sandwiched between one of the nozzle rows and the concave portion is thinner than the other region. A droplet discharge member that discharges droplets onto an object;
A carriage for moving the droplet discharge member in a first direction;
A transport mechanism for transporting the object in a second direction orthogonal to the first direction;
A capping device for improving the droplet discharge property of the droplet discharge member,
The droplet discharge member has a droplet discharge member in which a plurality of nozzle rows each having a plurality of nozzle openings for discharging droplets are formed,
The capping member is
A cap member covering the plurality of nozzle rows;
A pump that generates a negative pressure in a space surrounded by the cap member and the droplet discharge member,
The droplet discharge device according to claim 1, wherein the cap member is formed with a recess facing the one of the plurality of nozzle rows in a state of covering the nozzle rows.   The droplet discharge device according to claim 1, wherein an opening communicating with the pump is formed in the recess.   10. The droplet discharge device according to claim 8, wherein one of the plurality of nozzle rows discharges a droplet that is more easily clogged than a droplet discharged from another nozzle row. Each having a plurality of recesses facing one of the plurality of nozzle rows,
11. The droplet discharge device according to claim 8, wherein the number of the plurality of recesses is smaller than the number of the nozzle rows.   The droplet discharge device according to any one of claims 8 to 11, wherein the recess is provided with a plurality of openings communicating with the pump. A droplet absorbing member that absorbs the droplet is disposed on the cap member,
The droplet discharge device according to any one of claims 8 to 12, wherein a droplet absorbing member in a region sandwiched between one of the nozzle rows and the recess has a lower density than other regions. . A droplet absorbing member that absorbs the droplet is disposed on the cap member,
The droplet discharge according to any one of claims 8 to 12, wherein a thickness of the droplet absorbing member in a region sandwiched between one of the nozzle rows and the recess is thinner than the other region. apparatus.