JP2005112605A - Reverse transfer device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To constitute a small image formation device as a device capable of double-face printing only by mounting an option unit to the device, simplify the constitution of the option unit, and save a space. <P>SOLUTION: An option unit 50 is detachably constituted on one side of a device body 2 of an image formation device 1 as well as a manual paper feeding tray 25. A reverse transfer path 55 is installed to the option unit 50, and an exhaust path 20 and a reverse transfer path 55 are connected with a converge part 7 at a bottom part of the paper transfer path under a condition that it is mounted to the device body 2. Also, a drive mechanism relative to a transfer roller device 60 and the like, and a control mechanism are accommodated in a tolerance part on a rear side inside a body frame of the option unit 50, so that a noise source is not arranged on a front side of the device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reversing conveyance device that conveys a single-side recorded paper in a returning direction toward recording on the back side in an image forming apparatus capable of recording images on both sides of the paper, and in particular, simplifies the configuration of the reversing conveyance device. The present invention relates to a device that can be easily combined with a small device.

There have been known many examples of configuring an image forming apparatus capable of printing on one side of a sheet as an apparatus capable of double-sided recording by providing a reverse conveyance unit in combination. For example, a reversing conveyance device configured as one unit is combined by connecting a reversing conveyance path that connects between a recording paper discharge unit of a small image forming apparatus and a lower paper feeding unit, There is also known an apparatus configured so that a single-sided recording sheet can be reversed and returned to the paper feeding unit and then recorded on the back side of the sheet when the recording unit is passed through. The sheet reversing unit is provided with a combination of a conveying means on a reversing path for conveying a single-sided copy sheet and a reversing mechanism for reversing the sheet and guiding it toward the recording on the back side. For this purpose, a small-sized image forming apparatus having a single-sided printing function can be connected to the sheet conveyance path by simply positioning and mounting the sheet reversing unit on one side thereof, and between the apparatus body and the optional unit. , So that the paper transporting action can be performed easily (see, for example, Patent Document 1).
JP 2001-206646 A

  Even when the paper reversing unit of the conventional example is mounted in combination on the side of the apparatus main body, it is driven separately from the drive source of the apparatus main body in order to drive the conveyance roller device provided in the unit. A transmission system is provided. However, in order to provide the reversing unit in combination with a side portion of a small-sized image forming apparatus, means for connecting a paper detection sensor, a cover open / close detection sensor, or the like to the control device of the apparatus main body at the connection portion. Must be provided. In addition, in the frame of the reversing unit, it is necessary to dispose a driving source, a driving force transmission system, and the like on one side of the sheet conveyance path.

  In addition, by providing a control board or the like for controlling the operation of each mechanism arranged in the reversing unit according to the detection information from the sensors and the operation signal from the apparatus main body, There is also a problem that the wiring connected to it becomes complicated. Furthermore, between the reversing unit and the apparatus main body, there is also a problem that a harness used for signal transmission and power supply becomes longer. If the apparatus / mechanism and wiring are combined in a complicated manner, the reversing unit Therefore, it is necessary to provide a large accommodating portion on the side of the apparatus, and there is a problem that the apparatus cannot be reduced in size and space.

  The present invention provides a device that can reduce the size and space of a unit by disposing a driving mechanism on one side of a reversing conveyance device in a reversing unit that returns single-sided recorded paper to a paper feeding unit. It is aimed.

The present invention relates to a reversing and conveying apparatus having a reversing conveying path that conveys a single-sided recorded sheet in a returning direction toward recording on the back side, and a conveying unit that conveys the sheet in the reversing conveying path.
In the first aspect of the present invention, a drive source for driving the transport unit is disposed on one side of the reverse transport device orthogonal to the paper transport direction.
A part of the driving force transmitting means for transmitting the driving force to the conveying means is arranged on the other side of the reverse conveying apparatus.

The invention according to claim 2 is characterized in that the conveying means for conveying the sheet in the reverse conveying path is a conveying roller device, and a part of the driving force transmitting means is a conveying roller shaft.
The invention of claim 3 is characterized in that an electrical component including the drive source is disposed only on one side of the apparatus.
The invention according to claim 4 is characterized in that one side of the device is a rear side of the device.

  With the configuration as described above, the optional unit mounted in combination with the apparatus main body can be integrally provided with a guide mechanism for transporting paper, a transport roller device, a drive source, and the like. It can be compact. In addition, regardless of whether the device is configured as a single-sided recording specification or a double-sided recording specification, it is possible to use the same basic configuration of the device, so that the members can be shared, and low cost and space-saving can be achieved. Make it possible. Furthermore, when an optional unit for double-sided recording is installed, noise-generating members such as the drive source can be concentrated on the rear side of the apparatus main body, so that noise generated from the apparatus can be confined. .

  In the embodiments described below, a small-sized single-sided recordable image forming apparatus has a basic configuration, and an apparatus capable of double-sided recording only by attaching an optional unit to the side surface of the apparatus main body. Can be easily configured. In addition, the apparatus main body of the image forming apparatus is not limited to a small-sized image forming apparatus as described below, and can be configured to be any known image forming apparatus. The optional unit basically has a configuration as shown in the figure, but in addition to this, depending on the position of the paper transport path of the target apparatus main body, the paper transport path (reversing path) of the option unit. ) And the arrangement position of the transport roller device and the like can be changed. As an image forming apparatus described below, in addition to an apparatus having only a function as a general copying machine or a printer, an apparatus configured as a multifunction machine in combination with a function of a facsimile machine (FAX) is an object. However, since only the mechanism for creating the recording paper has the gist of the present invention, in the following description, the configuration of the paper transport mechanism will be mainly described.

  The configuration of the image forming apparatus will be described according to the illustrated example. An image forming apparatus 1 shown in FIG. 1 is configured as an apparatus capable of producing recording paper using an electrophotographic method, and an image of a document is read on an upper part of an apparatus main body 2 provided with a recording unit. A combination of image reading devices 30 is provided. The apparatus main body 2 of the image forming apparatus 1 is provided with a paper feed tray 3 at the lowermost part thereof so that paper can be fed toward the recording unit by a paper feed roller 4. In addition, a sheet feeding device equipped with one or a plurality of sheet feeding trays or the like is separately provided in the lower part of the apparatus main body 2, and a sheet of different sizes is accommodated in the sheet feeding unit. It is also possible to easily cope with this.

  Corresponding to the sheet conveyance path 5 arranged on one side surface of the apparatus main body 2, a recording unit 10 is provided in the upper part of the sheet feeding unit, and the recording unit records a toner image on the sheet. Then, fixing is performed through the fixing device 18 provided on the upper portion, and the recording paper is discharged to the discharge tray 22. In the lower part of the recording unit 10, the sheets separated one by one from the sheet feeding tray 3 by the sheet feeding roller 4 are stopped by the registration roller device 6 at the position of the merging unit 7 in the sheet conveying path. Provided. In the registration roller device 6, the toner image formed on the photoconductive drum 11 is synchronized with the toner image and works to feed out the paper. In addition, the leading edge of the paper is abutted against the nip position of the roller. And control so that the sheet is not conveyed obliquely by the recording unit.

  The recording unit 10 is provided with a charging unit 12, a writing unit 13, a developing device 16, a transfer unit 14, a cleaner 15, and the like around the photosensitive drum 11 according to a predetermined arrangement relationship. For the photosensitive drum 11 arranged in the recording unit 10, the surface of the photosensitive drum 11 is uniformly charged by an arbitrary discharge means, for example, discharge from the corotron 12, and then the original is scanned. Light information is emitted from the writing device 13 to form an electrostatic latent image on the surface of the photosensitive drum. Then, toner is supplied from the paper feed roller 17 of the developing device 16 to the electrostatic latent image to make it visible as a toner image, and the toner image is transferred to a sheet. At a position where the toner image is transferred to the paper, a predetermined value of voltage is applied to the transfer roller while conveying the paper so that the paper is sandwiched between the photoconductive drum and the transfer roller 14. The transfer to the sheet is performed in the same manner as in the case of an image forming apparatus using a conventional general electrophotographic system.

  The sheet on which the toner image has been transferred is sent to a fixing device 18 provided at the top thereof, and the toner melted by the heat of the heat roller 19 is pressed from behind the sheet by a pressing roller 19a to be fixed on the sheet. Therefore, the same fixing action as that of a general heat roller type fixing device is performed. The paper fixed as described above is sent to the discharge tray 22 by the discharge roller device 21 through the discharge path 20, and when a plurality of recording papers are continuously discharged, the image surface faces downward. Are stacked one after another. In addition, when the apparatus main body 2 is configured as a single-sided recording apparatus, the discharge roller apparatus 21 has a drive system configured to be driven only in one side. On the other hand, as will be described below, when the apparatus main body 2 is configured as an apparatus capable of double-sided recording, the conveying roller apparatus 21 is illustrated so as to be capable of forward and reverse rotation. It is connected to a driving device that is omitted, and an operation is performed to return the single-sided recording paper to the paper feed unit through the reverse conveyance path. The configuration of the device for that purpose will be described in detail later.

  Further, a manual feed tray 25 is provided on the side of the apparatus main body 2 on the side where the sheet conveyance path 5 is arranged, that is, on the right side of the drawing, and the apparatus main body is associated with the manual feed tray 25. 2, a paper feed roller 29 is provided, and the paper conveyance path is formed up to the junction 7. The manual feed tray 25 is provided with a second tray member 27 so as to be swingable with respect to the tray main body 26, and when feeding a large size paper, the second tray 27 is greatly expanded. To. Further, the manual feed tray 25 is provided so as to be swingable with respect to the apparatus main body via a hinge portion 28. When the tray is not used, the manual feed tray 25 is provided so as to be stood on the side surface of the apparatus main body.

  An image reading device 30 is provided on the upper part of the apparatus main body 2, and a scanning device 35 is provided inside the frame 32 of the reading device 31 so as to be movable in the left-right direction in the figure. A large platen 33 corresponding to a flat bed scanner (FBS) and a small platen 34 corresponding to an automatic document feeder (ADF) are provided above the frame 32 of the reading device 31. Then, the reading operation is performed on the original of the book set on the platen 33 while moving the scanning device 35 at a predetermined speed. Further, when reading using the ADF function, the document conveyed in the document conveyance path 45 of the ADF 41 is read with the scanning device 35 stopped at the position of the small platen 34.

  The scanning device 35 provided so as to be movable in the frame 32 of the reading device 31 is provided so as to be reciprocally movable at a constant speed by a drive mechanism (not shown), and is set on the platen 33 using the FBS function. A document is read. The scanning device 35 is provided with a lamp 36 at the top of its moving frame, and a number of mirrors 37 are combined in the frame so as to reflect light at a predetermined angle and reflect light. The optical path is configured to have a predetermined length. Then, the light reflected by the multiple mirrors 37... Is imaged on a CCD 39 as a photoelectric conversion means via a lens 38, and the image light is converted as a digital signal by the CCD to form a photosensitive drum. It is possible to cope with an arbitrary usage method such as direct transmission or transmission to another FAX apparatus using the image transmission function of the FAX apparatus.

  The upper device 40 provided on the upper portion of the reading device 31 so as to be openable and closable with respect to the large platen 33 has a large front side on the rear side of the frame 32 of the image reading device 30 via a hinge member (not shown). It is supported so that it can be opened and closed. The upper device 40 is integrally formed with a function of the ADF 41 and a plate member serving as a document discharge tray 48 and a platen cover. The ADF 41 includes a document tray 42, a document conveyance path 45 formed in a substantially U shape in the horizontal direction, and a discharge tray 48 positioned at the end of the document conveyance path 45, as in a conventionally known apparatus. Composed.

  Then, the original set on the discharge tray 42 is taken out by the pickup roller 43, separated one by one by the paper separating device 44, conveyed at a constant speed by the conveying roller device 46, and placed below the small platen 34. The image is read by the stopped scanning device 35. The document that has been read is sent out toward the discharge tray 48 by the discharge roller device 47, but the reading operation is continued while the documents set on the document tray 42 are sequentially sent. Note that the image reading operation of the document by the image reading device 30 is performed by operating information input to or selected by the control panel of the image forming apparatus. In other words, based on information selected by the operator, such as selection of the recording paper size and information on the setting of the enlargement / reduction ratio, an image reading operation is performed by the reading device, so that the recording paper can be created and the FAX function can be set. It is used as information for image transmission using.

  In the image forming apparatus 1 configured as described above, an optional unit 50 as an auxiliary means (sheet reversing conveyance mechanism) for double-sided recording can be mounted on the side of the apparatus body 2 as necessary. doing. First, when the image forming apparatus is configured to be capable of only single-sided recording without the optional unit, a marginal space 9 is formed on the side surface of the apparatus body 2 as shown in FIG. In this state, the manual feed tray 25 is accommodated in the space portion 9. Therefore, when the manual feed tray 25 is not used, the space 9 on the side of the apparatus main body is placed in a state where the bottom plate portion of the main body of the manual feed tray 25 closes the side opening. In the state as described above, the operation of creating the recording paper by transferring the toner image to the paper fed from the paper feeding unit of the apparatus main body by the recording unit can be continued.

  When the optional unit 50 is attached to the space portion of the apparatus main body 2 to form an apparatus capable of duplex recording, a main body frame 51 is mounted on the side of the apparatus main body 2 as shown in FIG. In order to attach the main body frame 51, any connecting means can be used. Further, when the option unit 50 is mounted on the apparatus main body 2 to form a double-sided recording sheet, it is necessary to reversely convey the one-side recorded paper toward the reverse conveyance path 55 of the option unit 50. Therefore, the discharge roller device 21 provided at the end of the discharge path 20 is configured as a forward / reverse conveyance roller. That is, when the optional unit 50 is installed, the drive transmission system of the apparatus main body is provided with a drive transmission mechanism capable of switching the drive in the forward and reverse directions with respect to the discharge roller device 21, and the control input to the control panel of the apparatus Based on the information, the single-sided recorded paper is returned to the optional unit, and the recording paper created under other conditions is transported so that it is discharged toward the discharge tray. The operation and the control operation for the sheet conveying apparatus are performed.

  In the optional unit 50, the main body frame 51 and the inner frame member 57 are disposed so as to sandwich the reverse conveyance path 55, and the reverse conveyance path 55 provided between the two members 51 and 57 is: It is defined by the outer guide surface 56 and the inner guide surface 56a. As shown in the figure, the inner frame member 57 of the option unit 50 is configured such that the end of the inner frame member 57 is combined with a block member 9 a that also serves as an inner wall of the space portion 9 of the apparatus main body 2. It is attached to the apparatus main body 2 by attaching to. In the state where the option unit 50 is mounted on the side surface of the apparatus main body 2, the manual feed tray 25 cannot be closed in a state of being completely stood, but can be held along the side surface so as not to interfere with normal operation. To.

  Since the optional unit 50 can be attached only to the required image forming apparatus, only the system such as signal transmission and power feeding is connected to the drive / control means of the apparatus main body 2. It is comprised so that operation | movement can be performed. When the option unit 50 of FIG. 3 is viewed from the apparatus main body 2 side, it is configured as shown in FIG. 4, and the (inner) surface of the main body frame 51 serves as an outer guide surface of the reversal conveyance path 55. It is provided to act. The outer guide surface 56 is formed so that a large number of ribs protrude in parallel with the paper conveyance direction, but the ribs are not shown. The reverse conveyance path 55 is provided with two conveyance roller devices 60 and 62 at a predetermined interval, and the conveyance roller devices 60 and 62 are driven when conveying the single-side recorded paper.

  The body frame 51 of the option unit 50 is provided with marginal parts 52 and 52a at positions corresponding to both sides of the sheet conveyance path portion, that is, both sides of the rear side and the front side of the apparatus body 2. Yes. The margin portion 52 formed on the rear side of the apparatus main body is provided with a driving device 65 for the transport roller devices 60 and 62, and includes a motor 65a, a speed reduction transmission mechanism 66, and two transport roller devices 60 and 62. And a conductive member 67 for driving force conduction between them. The conductive member 67 can also be provided in the margin part 52a on the front side of the apparatus as shown by a chain line in the figure, and the mechanism is a pulley provided at the end of the roller shafts 61 and 63. The conductive belt 67 may be stretched over 64 and 64a.

  When the option unit 50 is attached to the apparatus main body 2 and a jam occurs in the reverse conveyance path 55, the option unit 50 can be opened to perform jam processing. The shaft support portions 53 and 53a provided on the main body support shaft 54 and 54a provided on the apparatus main body 2 can be pivotally supported. If the upper portion of the option unit 50 can be opened widely using the shaft support means, it is possible to easily perform the jam processing operation in the reverse conveyance path 55. When the lower portion of the option unit 55 is pivotally supported and attached to the apparatus main body 2, the manual feed tray 25 swings outside the option unit 50 via a separate shaft as shown in FIG. Since it is provided so as to be movable, there is an inconvenience that the angle at which the option unit 50 can be opened is limited because the manual feed tray 25 interferes. However, there is no support for the operability of the apparatus except that the angle is limited when the option unit 50 is opened and closed.

  Since the rear margin 52 of the option unit 50 is configured as a relatively large space, a large space remains even if only the driving device 65 is accommodated. Therefore, in addition to the power supply means for supplying power to the motor of the driving device 65 with respect to the rear side margin 52, a sheet detection sensor, a cover open / close detection sensor, and a control for controlling these sensors and power supply A substrate or the like can be disposed in the control device housing portion 68. As described above, the power supply device, the control means, and the like are arranged on the rear side of the option unit 50, so that the harness of the signal transmission system connected to the control device of the device body 2 is intricately intertwined. And will not be placed. And, between the device main body 2 and the option unit 50, the minimum necessary harness provided on each rear side is connected via a short connection path, and the drive traditional mechanism By gathering such noise sources on the rear side of the apparatus, it becomes possible to protect the environment of the office where the image forming apparatus is arranged from the influence of noise.

  In the state where the option unit 50 having the above-described configuration is mounted on the side of the apparatus main body 2, as described with reference to FIG. 3, the upper portion of the reverse conveyance path 55 is connected to the discharge path of the apparatus main body. Further, the lower part of the reverse conveying path 55 is connected from the lower part of the block member 9a to the alignment position by the registration roller device 6 to constitute the reverse conveying path. Then, the single-sided recorded paper prepared through the fixing device 18 passes through the guide surface on the lower surface of the gate 23, and the end portion of the paper is discharged by the discharge roller device 21 positioned at the end portion of the discharge path 20. The discharge roller device 21 is driven in the reverse direction at the timing when it is nipped and has passed through the gate portion.

  Then, the one-side recorded paper is guided toward the reverse conveyance path 55 of the option unit 50 through the guide surface on the gate 23, and conveyed downward by the conveyance roller devices 60 and 62 in the reverse conveyance path 55, The leading end of the sheet is inserted into the nip portion of the registration roller device 6 through the junction 7 at the bottom of the sheet conveying path 5 and stopped. Thereafter, an additional feeding action is applied by the transport roller device 62 so that a loop is formed on the paper so that the front edge of the paper is uniformly pressed against the registration roller device 6. Perform matching and wait.

  As described above, the information on the next image is transmitted to the recording unit 10 while the single-side recorded paper is waiting, and charging, writing, and developing operations on the photosensitive drum 11 are sequentially performed. In the middle of the operation, the registration roller device 6 starts to be driven in accordance with the information on the front end portion of the toner image formed on the photosensitive drum 11, and the one-side recorded paper is transferred from the photosensitive drum to the toner image transfer portion. Feed the paper toward. A double-sided recording sheet is created by applying a predetermined potential while pressing from the back of the sheet with a transfer roller, transferring the toner image on the photosensitive drum onto the sheet, and then fixing it with the fixing device 18. Therefore, the sheet is discharged as it is to the discharge tray 22 by the discharge roller device 21.

  As described above, the gate device 23 that guides the paper above the fixing device 18 is provided with a weak biasing means that biases the shaft 23a in one direction, such as a torsion spring. Thus, the sheet discharged from the fixing device 18 is allowed to pass by swinging the gate member 23. Then, when the paper has finished passing, it is preferable that the discharge path 20 and the reverse conveyance path 55 are automatically connected so that the guidance for returning the single-side recorded paper can be performed smoothly. In order to control the swing operation of the gate member, a conventionally known gate switching mechanism can be appropriately applied.

  The image reading apparatus described as an embodiment of the present invention is an apparatus that combines ADF and FBS functions. However, the scanning apparatus may be configured as a small-sized reading apparatus having only an FBS function. Further, in the image forming apparatus, the configuration of the sheet conveying device and the recording unit can be an arbitrarily configured device without departing from the object of the present invention. It is not limited to the apparatus of the mechanism demonstrated. In addition, as long as the drive unit provided in the option unit can be easily sound-insulated, it is needless to say that means arranged on the front side of the device can be used. Therefore, by using the sheet transport mechanism that performs the operation of returning the one-side recorded sheet as described above, it is possible to simplify the structure of the apparatus and obtain image information with good image quality.

1 is an explanatory diagram illustrating a configuration of an image forming apparatus. It is explanatory drawing of the state which does not provide an option unit. It is explanatory drawing of the state which attached the option unit to the side part of the apparatus main body. It is explanatory drawing which shows the structure of the option unit seen from the inversion road side.

Explanation of symbols

1 image forming apparatus, 2 apparatus main body, 3 paper feed tray, 5 transport path,
6 registration roller device, 7 merging section, 10 recording section,
11 photosensitive drum, 12 charging corotron, 13 writing device,
14 transfer roller 5 cleaner, 16 developing device, 17 developing roller, 18 fixing device, 20 discharge path, 21 discharge roller device,
22 discharge tray, 23 gate, 25 manual feed tray,
26 tray body, 27 second tray, 28 hinge,
29 paper feed roller, 30 image reading device, 31 reading device,
32 frames, 33/34 platen, 35 scanning device,
36 lamp, 37 mirror, 38 lens, 39 CCD,
40 upper member, 41 ADF, 42 document tray,
43 Pickup roller, 44 Paper separation device, 45 Document transport path,
46 Conveying roller device, 47 Discharging roller device, 48 Discharging tray,
50 optional unit, 51 body frame, 52 margin,
53 Lower shaft support section, 54 Main body support shaft, 55 Reverse transfer path,
56 guide surface, 57 inner frame member, 60/62 conveying roller device, 65 driving device, 68 control device accommodating portion.

Claims (4)

A reverse conveyance path for conveying the single-side recorded paper in the returning direction toward the recording on the back surface;
A reversing and conveying device having conveying means for conveying paper in the reversing and conveying path,
A drive source for driving the transport means is disposed on one side of the reverse transport device orthogonal to the paper transport direction,
A reverse conveying apparatus characterized in that a part of driving force transmitting means for transmitting driving force to the conveying means is arranged on the other side of the reverse conveying apparatus. The conveying means for conveying the paper in the reverse conveying path is a conveying roller device,
The reverse conveying device according to claim 1, wherein a part of the driving force transmitting means is a conveying roller shaft.   The reverse conveying apparatus according to claim 1, wherein an electrical component including the driving source is disposed only on one side of the apparatus.   4. The reverse conveying device according to claim 3, wherein one side of the device is a rear side of the device.

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