JP2009298544A - Paper feeder and image forming apparatus having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder simply configured for reduction in cost and capable of smoothly drawing in and out its paper feed cassette, easily loading the paper feed cassette into an appropriate position, and carrying out stable paper feed operation. <P>SOLUTION: The paper feeder 20 includes a main body 21, the paper feed cassette 22, a lift plate 25, a lift plate push-up mechanism 40, and its drive unit 50. The drive unit 50 has a drive-side connecting gear 51 connected to the lift plate push-up mechanism 40 when the paper feed cassette 22 is loaded to the main body 21; the lift plate push-up mechanism 40 is provided with a lift-side connecting gear 44 which is disposed on a side face of the paper feed cassette 22, engaged with the drive-side connecting gear 51 of the drive unit 50 when the paper feed cassette 22 is loaded to the main body 21, and is supported to be displaceable toward or away from the drive-side connecting gear 51. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a paper supply device such as a cut paper, which can be applied to an image forming apparatus represented by a copying machine or a printer. The present invention also relates to an image forming apparatus equipped with this paper supply device.

  The paper supply device is indispensable for feeding cut paper or the like in an image forming apparatus represented by a copying machine or a printer. Many paper supply devices in image forming apparatuses stock a large number of sheets before printing in a paper storage unit, and separate and supply the paper one by one from the uppermost layer of paper stacked in the paper storage unit. Such a sheet supply device is used in a cassette type sheet feeding unit, a manual sheet feeding unit, and a document feeding unit of an image forming apparatus.

  There are a roller supply method and a suction supply method as a method of feeding paper from the paper supply device to the outside, and the roller supply method is generally widely used. In the roller supply method, a pickup roller disposed on the upstream side presses against the uppermost layer of the sheet bundle, and the sheet is delivered to a sheet feeding roller disposed on the downstream side. It sends out to the outside.

As a method of pressing the uppermost layer of the sheet bundle against the pickup roller, a lift plate on which the sheets are stacked is pushed up from below by a driving device equipped with a motor and the like, and a method of pushing up by a biasing means such as a spring And exist. In the paper cassette, when the lift plate is pushed up to the paper supply position by a drive device equipped with a motor or the like, the drive device is outside the paper feed cassette and is attached to the paper supply device body or the paper supply device. It is mounted in the image forming apparatus. Examples of such a paper supply device can be found in Patent Documents 1 and 2.
Japanese Patent Laid-Open No. 5-193761 (page 5-6, FIG. 1-2) Japanese Patent Laying-Open No. 2003-2459 (page 4, FIG. 4)

  Here, in the conventional sheet supply apparatus, when the stored sheet cassette is pulled out, the pulling operation may be felt very heavy due to the configuration of the drive device for the lift plate. In view of this, the sheet feeding cassette middle plate lifting device described in Patent Document 1 detects that the user has put a hand on the handle in order to pull out the sheet feeding cassette, and moves the lift motor to the middle plate (lift plate). At the same time as the rotation of the sheet is lowered, the connection of the gear for driving the intermediate plate is released so that the sheet feeding cassette can be pulled out smoothly. However, in this configuration, in order to release the connection between the lift plate and the drive device, a sensor is required at the handle, and the gear group of the drive device is arranged in a complicated manner considering the connection release. There is also a need. As a result, there is a possibility that the parts cost and the production cost are greatly increased, and the motor must be controlled.

  On the other hand, the sheet feeding device (paper feeding device) described in Patent Document 2 is provided with an intermediate gear that is a part of a drive mechanism that transmits power to a lifter that lifts and lowers an intermediate plate (lift plate). Thus, the middle plate can be raised and lowered by the drive mechanism when the paper cassette is stored in the apparatus main body, and the middle plate is lowered by the action of gravity when the paper cassette is pulled out. In this configuration, when pulling out the paper cassette, the pulling operation does not feel heavy and can be pulled out relatively smoothly. However, when the paper cassette is stored in the main body, it is provided in the paper cassette. There is a high possibility that the teeth of the intermediate gear collide with the gear teeth on the apparatus main body side that engage with the teeth of the intermediate gear. Therefore, there is a possibility that the paper feeding cassette cannot be stored in a predetermined position after a long time. Furthermore, there is a concern that the gear for driving the lift plate may be damaged by repeating the storing operation, and there is a possibility that a stable paper feeding operation cannot be performed.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and in a paper supply apparatus having a drive device that pushes up a lift plate and displaces the lift plate to a paper supply position, with a simple structure that achieves cost reduction and a paper feed cassette. An object of the present invention is to provide a paper supply device that can smoothly pull out / store paper, can easily store a paper feed cassette in an appropriate position, and can perform a stable paper feeding operation. And It is another object of the present invention to provide an image forming apparatus equipped with such a paper supply device.

  In order to solve the above problems, the present invention provides a paper feed cassette that stacks and accommodates paper and can be pulled out / stored in a direction parallel to the paper transport direction with respect to the apparatus main body, The lift plate is disposed on the upper surface of the apparatus, the lift plate is provided on the upper surface of the apparatus, the lift plate is provided on the paper cassette, and the lift plate is pushed up and displaced to the paper supply position. And a drive device that includes a drive-side connecting gear that is connected to the lift plate push-up mechanism when the paper feed cassette is stored in the device main body. The plate push-up mechanism is provided on the side surface of the paper feed cassette and engages with the drive side coupling gear of the drive device when the paper feed cassette is stored in the apparatus main body, and the engagement is released. With no range, it was decided to include the lifting-side connecting gear which is supported in the displaceable in a direction approaching / separating from the drive coupling gear.

  In the paper supply apparatus having the above-described configuration, the paper feed cassette can displace the lift side connection gear in a direction of approaching / separating from the drive side connection gear at a support portion of the lift side connection gear. A long hole was provided.

  In the paper supply device having the above-described configuration, when the lift side connection gear and the drive side connection gear come into contact with each other, the lift side connection gear is separated from the drive side connection gear while rotating. It was supposed to be configured to extend in the direction.

  In the paper supply device having the above-described configuration, when the lift side coupling gear rotates by obtaining power from the driving device, the lift side coupling gear is displaced in a direction approaching the driving side coupling gear by the rotating force. did.

  In the present invention, the paper supply device is mounted on the image forming apparatus.

  According to the configuration of the present invention, the paper is stacked and stored, and can be pulled out / stored in a direction parallel to the paper transport direction with respect to the apparatus main body, and is disposed inside the paper feed cassette. A lift plate on which the paper is placed, a lift plate provided in the paper feed cassette that pushes the lift plate to displace it to a paper supply position, and a device main body that provides power to the lift plate push-up mechanism. In the paper supply device including the drive device for transmitting, the drive device includes a drive side connection gear that is connected to the lift plate push-up mechanism when the paper feed cassette is stored in the device body, and the lift plate push-up mechanism is , Provided on the side surface of the paper feed cassette, and engages with the drive side coupling gear of the drive device when the paper feed cassette is stored in the apparatus main body, and in a range where the engagement is not released, Since the lift-side coupling gear supported so as to be displaceable in the direction approaching / separating from the moving-side coupling gear is provided, a slight amount is provided between the driving-side coupling gear and the lift-side coupling gear to be engaged. Play can be provided. As a result, there is a space for rotation between the two gears, a high load is applied when the paper cassette is pulled out of the main body of the apparatus, and the teeth of both gears collide when stored. Can be prevented. Such a lift side connecting gear support mechanism can be obtained with a simple configuration. Therefore, the paper cassette can be smoothly pulled out / stored with a simple configuration with a low cost, and the paper cassette can be easily stored at an appropriate position, so that stable paper feeding is possible. A paper supply apparatus capable of performing the operation can be provided.

  In addition, the sheet feeding cassette is provided with a long hole at the support portion of the lift side connection gear so that the lift side connection gear can be displaced in a direction approaching / separating from the drive side connection gear. In addition, a support mechanism for the lift side connecting gear can be obtained with a simpler configuration. Therefore, with a configuration in which the cost is further reduced, the paper cassette can be smoothly pulled out / stored, and the paper cassette can be easily stored at an appropriate position.

  Further, the elongated hole is configured in such a manner that when the lift side connection gear and the drive side connection gear come into contact with each other, the lift side connection gear extends in a direction away from the drive side connection gear while rotating. Therefore, it is possible to enhance the action of preventing the teeth of the lift side connecting gear and the driving side connecting gear from colliding with each other when the paper cassette is stored in the apparatus main body. Thereby, it becomes easy to engage a lift side connection gear and a drive side connection gear. Therefore, the paper feeding cassette can be stored more smoothly, and the effect of performing a stable paper feeding operation by storing the paper feeding cassette in an appropriate position can be improved.

  Further, when the lift side connecting gear rotates by obtaining power from the driving device, the lift side connecting gear is displaced in a direction approaching the driving side connecting gear by the rotating force. Even if play is provided between the connection gear and the drive-side connection gear, an effect that both gears are more easily engaged occurs. Therefore, it is possible to obtain a paper supply device that can perform a more stable paper supply operation.

  Further, in the present invention, since the paper supply device is mounted on the image forming apparatus, the paper cassette can be smoothly pulled out / stored with a simple configuration with low cost, and easy. In addition, it is possible to obtain an image forming apparatus that can store the paper feeding cassette in an appropriate position and can perform a stable paper feeding operation.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. Here, it is assumed that the paper supply device of the present invention is designed to be disposed below the image forming apparatus (printer).

  First, an image output operation of a printer, which is an example of an image forming apparatus equipped with the paper supply device of the present invention, will be described with reference to FIG. FIG. 1 is a schematic vertical cross-sectional right side view showing a printer equipped with a paper supply device according to an embodiment of the present invention. In FIG. 1, the left side is the front side of the printer, and the right side is the back side.

  As shown in FIG. 1, a paper supply device 20 is disposed below the printer 1. The paper supply device 20 is provided with a paper feed cassette 22 as a paper storage unit inside a main body 21, and paper P such as cut paper before printing is stacked and stored in the paper feed cassette 22. Has been. A paper feeding device 23 is disposed on the downstream side of the paper feeding cassette 22 in the paper conveyance direction, that is, on the upper left side in FIG. The sheet feeding device 23 separates and feeds the sheets P one by one toward the upper left of the sheet feeding cassette 22 in FIG. The paper feed cassette 22 is slid horizontally and moved to the front side of the main body 21, that is, to the left in FIG.

  A manual feed tray 2 is provided in the center of the front surface of the printer 1. The manual paper feed tray 2 is rotatable in a vertical plane around a support shaft provided at the lower end and extending substantially horizontally in the horizontal direction. The manual paper feed tray 2 has an upper end that is openable and closable around the support shaft in the direction of the outside of the printer 1, and can open and unfold to form a sheet P or the like on its upper surface. Become.

  On the manual paper feed tray 2, paper of a size that is not in the paper feed cassette 22, paper that is to be fed one by one, such as thick paper and an OHP sheet, is placed. The paper placed on the manual paper feed tray 2 is sent leftward by a paper feed device 3 for the manual paper feed tray 2 disposed on the left side of the manual paper feed tray 2 in FIG. When not in use, the manual paper feed tray 2 is closed as shown in FIG.

  A paper feed path 4, a registration roller 5, an image forming unit 30, and a transfer roller 8 are disposed downstream of the paper feed cassette 22 and the manual paper feed tray 2 in the paper feed direction. The paper P sent out from the paper feed cassette 22 and the manual paper feed tray 2 passes through the paper feed paper conveyance path 4 and reaches the registration roller 5. The registration roller 5 corrects the oblique feeding of the paper P, measures the timing with the toner image formed by the image forming unit 30, and feeds the paper P to the transfer roller 8.

  Image data signals such as characters, graphics, and patterns from an external computer (not shown) are transmitted to the printer 1, and lasers controlled by the optical unit 7 provided above the image forming unit 30 based on the image data. Light L (dashed line in the figure) is irradiated. As a result, in the image forming unit 30, an electrostatic latent image of the original image is formed on the photosensitive drum 31 that is an image carrier, and the toner image is developed from the electrostatic latent image. The toner image is transferred to the paper P sent in synchronization by the registration roller 5 at a transfer nip portion formed by pressing the photosensitive drum 31 and the transfer roller 6 as a transfer member.

  A fixing device 8 is provided downstream of the image forming unit 30 and the transfer roller 6 in the sheet conveyance direction. The paper P carrying an unfixed toner image at the transfer nip is sent to the fixing device 8 where the toner image is heated and pressed by a heat roller and a pressure roller to be fixed.

  A discharge paper transport path 9, a paper discharge port 10, and a paper discharge unit 11 are disposed downstream of the fixing device 8. The paper P discharged from the fixing device 8 is sent upward through the discharge paper conveyance path 9 and is discharged from the paper discharge port 10 to the paper discharge portion 11 provided on the upper surface of the printer 1.

  Next, the configuration of the paper supply device 20 mounted on the printer 1 will be described with reference to FIGS. 2 to 7 in addition to FIG. 2 is a perspective view of the sheet supply device as seen from the rear side of the right side, FIG. 3 is a perspective view of the sheet cassette as seen from the rear side of the right side, FIG. 4 is a perspective view of the lift plate push-up mechanism as seen from the front, and FIG. FIG. 6 is a perspective view of the periphery of the lift plate push-up mechanism around the front of the paper feed cassette, FIG. 6 is a perspective view of the drive device of the lift plate push-up mechanism as viewed from the inside (paper feed cassette side), and FIG. It is the perspective view which looked at the engagement state with an apparatus from the inner side (paper feed cassette side).

  As described above, the paper supply device 20 is provided below the inside of the printer 1 shown in FIG. As shown in FIG. 2, the paper supply device 20 is configured to have a flat rectangular parallelepiped shape and is attached to the printer 1. In addition to the main body 21, the paper feed cassette 22, and the paper feed device 23, the paper supply device 20 includes a drive device 50 (see FIG. 6) of a lift plate push-up mechanism 40 (see FIGS. 4 and 5) described later. I have.

  As shown in FIG. 3, the paper feed cassette 22 is configured by a flat box whose upper surface is open, and stacks and stores paper P from the upper surface direction. The paper P is sent from the right side to the left side in FIG. 3 by the paper feeding device 23 shown in FIG. On the side surface of the paper feed cassette 22, a horizontal ridge 24 that allows a substantially horizontal sliding movement with respect to the main body 21 of the printer 1 is disposed. The horizontal ridges 24 are provided so as to extend in the paper transport direction of the paper feed cassette 22, that is, in the left-right direction in FIG.

  A guide rail (not shown) is provided inside the main body 21 of the paper supply device 20 shown in FIG. The guide rail extends substantially horizontally in the paper transport direction, that is, the front-rear direction of the paper supply device 20. This guide rail engages with a horizontal ridge 24 provided on the side surface of the paper feed cassette 22, thereby enabling the paper feed cassette 22 to be pulled out / stored in the direction parallel to the paper transport direction with respect to the main body 21. ing. The horizontal ridges 24 and the guide rails are provided on the left and right side surfaces of the sheet feeding cassette 22.

  As shown in FIG. 3, a lift plate 25 is provided inside the paper feed cassette 22. The paper P is placed on the lift plate 25. The upstream end of the lift plate 25 in the paper transport direction is supported on both side surfaces of the paper feed cassette 22, and the vertical surface along the paper transport direction with the support shaft 25 a (see FIG. 1) as the center and the downstream end as a free end. Can be rotated within.

  A lift plate push-up mechanism 40 shown in FIGS. 4 and 5 is built in the lower portion of the lift plate 25 at the downstream end side and in the downstream portion of the paper feed cassette 22. The lift plate push-up mechanism 40 includes a push-up plate 41, a rotation shaft 42, a sector gear 43, and a lift side connection gear 44.

  The push-up plate 41 is provided on the inner bottom surface of the paper feed cassette 22 below the downstream portion of the lift plate 25 and is located at the center of the lift plate 25 in the paper width direction. As shown in FIG. 4, one end of the push-up plate 41 is fixed to the tip of a rotating shaft 42 that is arranged to extend in the paper width direction. The push-up plate 41 is provided so as to protrude outward in the radial direction of the rotary shaft 42.

  A sector gear 43 is fixed to the other end of the rotating shaft 42. The sector gear 43 is located in the vicinity of the right side surface of the paper feed cassette 22 and is accommodated inside the gear holder 45 shown in FIGS. 4 and 5. The sector gear 43 is rotatable in a vertical plane along the paper conveyance direction around the axis of the rotation shaft 42, that is, the axis extending in the paper width direction perpendicular to the paper conveyance direction.

  The lift side connection gear 44 is engaged with the sector gear 43. The lift-side connecting gear 44 is also rotatable in a vertical plane along the paper transport direction around an axis extending in the paper width direction. The lift-side connecting gear 44 is arranged inside the gear holder 45, similar to the sector gear 43, but a part of the upper side upstream in the paper transport direction is exposed to the outside from the opening 46 of the gear holder 45. ing. In addition, the detailed structure of the support location of the lift side connection gear 44 is demonstrated later.

  The drive device 50 (see FIG. 6) of the lift plate push-up mechanism 40 configured as described above is provided outside the paper feed cassette 22 and on the main body 21 side of the paper supply device 20 shown in FIG. . The driving device 50 is disposed at a location close to the right side surface of the paper supply device 20. The drive device 50 includes a motor that is a drive source and a plurality of gears.

  As shown in FIG. 6, a drive side connecting gear 51 is provided at the ends of the plurality of gears of the drive device 50. The drive side connecting gear 51 is disposed on a surface facing the right side surface of the paper feed cassette 22 and in the vicinity of the paper feed cassette 22. A part of the drive-side connecting gear 51 on the lower side downstream in the paper transport direction is exposed from the opening 52 of the drive device 50 toward the paper feed cassette 22.

  Further, the drive side connection gear 51 is disposed at a position corresponding to the lift side connection gear 44 of the paper feed cassette 22. Accordingly, as shown in FIG. 7, when the paper feed cassette 22 is stored in the main body 21, the lift side connection gear 44 and the drive side connection gear 51 are engaged and connected. Therefore, the driving device 50 can transmit the power to the lift plate push-up mechanism 40 via the lift-side connection gear 44 and the drive-side connection gear 51 to push the downstream end side of the lift plate 25 to the paper supply position. it can.

  Next, the detailed configuration of the support part of the lift side connection gear 44 of the lift plate push-up mechanism 40 will be described with reference to FIGS. 8 to 11 in addition to FIGS. 5 and 6. FIG. 8 is a perspective view showing the vicinity of the lift plate push-up mechanism at the front part of the paper feed cassette similar to FIG. 5, and shows a state where the gear holder and the gear group are removed, and FIG. 9 is a lift side connection gear and a drive side connection gear. FIG. 10 is a partially enlarged view of the portion of the lift side connecting gear and the drive side connecting gear as in FIG. 9 seen from the inside, and shows a state where both gears are separated from each other. FIG. 11 is a partially enlarged view of the lift side connection gear and the drive side connection gear as in FIG. 9 viewed from the inside, and shows a state in which both gears are rotating with power.

  The lift-side connecting gear 44 is rotatable at both ends of a shaft portion 44 between a bearing 47 provided on the frame 22a of the paper feed cassette 22 shown in FIG. 8 and a bearing 48 provided on the gear holder 45 shown in FIG. It is supported by.

  As shown in FIG. 9, the bearings 47 and 48 are configured by long holes extending in the paper conveyance direction, that is, substantially horizontally in the front-rear direction of the paper supply device 20. The direction in which the long holes constituting the bearings 47 and 48 extend is inclined with respect to the normal line N at the contact point between the lift side connection gear 44 and the drive side connection gear 51 and forwardly away from the normal line N. It extends towards. As a result, the lift-side connecting gear 44 can be displaced in a direction along the pulling / storing direction of the paper feed cassette 22 and in a direction approaching / separating from the driving-side connecting gear 51.

  It should be noted that the length of the long holes of the bearings 47 and 48 is such that the engagement with the drive side connecting gear 51 is not caused when the paper feed cassette 22 is stored in the main body 21 no matter how the lift side connecting gear 44 is displaced. It is the length of the range which is not cancelled | released (refer FIG.9 and FIG.11).

  On the other hand, both ends of the shaft portion 51a of the drive side connecting gear 51 are rotatably supported by the bearings 53 of the drive device 50 shown in FIG. 6 (the bearing farther from the paper feed cassette 22 side is not shown). ). As shown in FIG. 9, the bearing 53 has a circular shape. Therefore, the drive side connecting gear 51 is not displaced in the direction along the pulling / storing direction of the paper feed cassette 22.

  In this way, the paper P is stacked and stored, and the main body 21 is disposed inside the paper feed cassette 22 and the paper feed cassette 22 that can be pulled out / stored in a direction parallel to the paper transport direction. A lift plate 25 on which the paper P is placed and a lift plate push-up mechanism 40 that is provided in the paper feed cassette 22 and pushes the lift plate 22 up to displace it to a paper supply position. In the paper supply device 20 including a drive device 50 that transmits power to the push-up mechanism 40, the drive device 50 of the lift plate push-up mechanism 40 is connected to the lift plate push-up mechanism 40 when the paper feed cassette 22 is stored in the main body 21. The drive side connecting gear 51 is connected, and the lift plate push-up mechanism 40 is provided on the side surface of the paper feed cassette 22, and when the paper feed cassette 22 is stored in the main body 21, the drive device A lift-side coupling gear that is engaged with the drive-side coupling gear 51 of 0 and supported so as to be displaceable in a direction approaching / separating from the driving-side coupling gear 51 within a range in which the engagement is not released. 44 is provided, a slight play can be provided between the driving side connecting gear 51 and the lift side connecting gear 44 to be engaged. As a result, there is room for rotation between the two gears, a high load is applied when the paper cassette 22 is pulled out of the main body 21, and the teeth of both gears collide when stored. Can be prevented. Such a support mechanism for the lift-side connecting gear 44 can be obtained with a simple configuration. Therefore, the paper cassette 22 can be smoothly pulled out / stored with a simple configuration with low cost, and the paper cassette 22 can be easily stored in an appropriate position, which is stable. It is possible to provide a paper supply device 20 capable of performing a paper supply operation.

  Further, since the paper feed cassette 22 is provided with a long hole at a support portion of the lift side connection gear 44 so that the lift side connection gear 44 can be displaced in a direction approaching / separating from the drive side connection gear 51. In addition, a support mechanism for the lift-side connecting gear 44 can be obtained with a simpler configuration. Therefore, the paper cassette 22 can be smoothly pulled out / stored with a configuration in which the cost is further reduced, and the paper cassette 22 can be easily stored at an appropriate position.

  When the lift side coupling gear 44 abuts on the drive side coupling gear 51 when the paper cassette 22 is stored in the main body 21, as shown in FIG. Due to the relationship between the circle A) and the direction in which the long holes of the bearings 47 and 48 extend, it moves in the long hole in a direction away from the drive side connecting gear 51 while rotating in the direction indicated by the broken line arrow in the figure.

  That is, the long holes of the bearings 47 and 48 are arranged such that when the drive side connection gear 51 contacts the lift side connection gear 44 at the position of the circle A in FIG. 10, the drive side connection gear 51 rotates while the lift side connection gear 44 rotates. It is configured to extend in a direction away from the direction. As a result, it is possible to enhance the action of preventing the teeth of the lift side connecting gear 44 and the driving side connecting gear 51 from colliding with each other when the paper feed cassette 22 is stored in the main body 21. Thereby, the lift side connection gear 44 and the drive side connection gear 51 are easily engaged. Therefore, the paper cassette 22 can be stored more smoothly, and the effect of performing the stable paper feeding operation by storing the paper cassette 22 in an appropriate position can be improved.

  When the driving device 50 transmits power to the lift plate push-up mechanism 40 to push the lift plate 25 to the paper supply position, the drive side connecting gear 51 is viewed from the inside of the paper feed cassette 22 as shown in FIG. In the clockwise direction, the lift-side connecting gear 44 rotates counterclockwise. Thereby, the lift side connecting gear 44 tends to move while rolling from the front side to the rear side of the long holes of the bearings 47 and 48, that is, from right to left in FIG.

  That is, when the lift side connection gear 44 rotates by obtaining power from the drive device 50, the lift side connection gear 44 is displaced in a direction approaching the drive side connection gear 51 by the rotating force. As a result, even if play is provided between the lift-side connecting gear 44 and the driving-side connecting gear 51 that are engaged with each other, there is an effect that both gears are more easily engaged. Therefore, it is possible to obtain the paper supply device 20 that can perform a more stable paper feeding operation.

  In the present invention, since the paper supply device 20 is mounted on the printer 1, the paper cassette 22 can be smoothly pulled out / stored with a simple configuration with low cost, and can be easily supplied. The printer 1 that can store the paper cassette 22 in an appropriate position and can perform a stable paper feeding operation can be obtained.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  The present invention can be used in a paper supply apparatus including a lift plate that is lifted by a driving device and displaced to a paper supply position.

1 is a schematic right side view of a vertical section showing a printer equipped with a paper supply device according to an embodiment of the present invention. FIG. 2 is a perspective view of the paper supply device of FIG. FIG. 3 is a perspective view of the sheet feeding cassette of FIG. FIG. 4 is a perspective view of a lift plate push-up mechanism of the paper feed cassette of FIG. 3 as viewed from the front. FIG. 4 is a perspective view showing the vicinity of a lift plate push-up mechanism at the front portion of the paper feed cassette of FIG. It is the perspective view which looked at the drive device of the lift board pushing-up mechanism from the inner side (sheet feeding cassette side). It is the perspective view which looked at the engagement state of a lift board pushing-up mechanism and its drive device from the inner side (paper feed cassette side). FIG. 6 is a perspective view showing the periphery of a lift plate push-up mechanism at the front part of the paper feed cassette similar to FIG. 5 and shows a state in which the gear holder and the gear group are removed. It is the elements on larger scale which looked at the location of the lift side connection gear and the drive side connection gear from the inner side. FIG. 10 is a partially enlarged view of the lift-side connection gear and the drive-side connection gear as in FIG. 9 viewed from the inside, and shows a state in which both gears are separated from each other. FIG. 10 is a partially enlarged view of the lift side connection gear and the drive side connection gear as in FIG. 9 viewed from the inside, and shows a state in which both gears are rotating with power.

Explanation of symbols

1 Printer (equipment, image forming device)
DESCRIPTION OF SYMBOLS 20 Paper supply apparatus 21 Main body 22 Paper feed cassette 25 Lift board 40 Lift board push-up mechanism 44 Lift side connection gear 47, 48 Bearing (support location, long hole)
50 Drive device 51 Drive side coupling gear

Claims (5)

A paper feed cassette that stacks and stores paper and can be pulled out / stored in a direction parallel to the paper transport direction with respect to the main body of the apparatus, and is placed inside the paper feed cassette. And a lift plate push-up mechanism that is provided in the paper feed cassette and pushes up the lift plate to be displaced to a paper supply position, and a drive device that is provided in the apparatus main body and transmits power to the lift plate push-up mechanism. In the paper supply device,
The drive device includes a drive side connecting gear that is connected to the lift plate push-up mechanism when the paper feed cassette is stored in the device main body, and the lift plate push-up mechanism is provided on a side surface of the paper feed cassette to the device main body. When the paper cassette is stored, it engages with the drive-side coupling gear of the drive device, and can be displaced in a direction approaching / separating from the drive-side coupling gear as long as the engagement is not released. A paper supply device comprising a lift-side connecting gear supported.   The sheet feeding cassette is provided with an elongated hole at a support portion of the lift side connection gear so that the lift side connection gear can be displaced in a direction approaching / separating from the drive side connection gear. Item 2. The paper supply device according to Item 1.   The elongated hole is configured in such a manner that when the lift-side connecting gear and the driving-side connecting gear come into contact, the lift-side connecting gear extends in a direction away from the driving-side connecting gear while rotating. The paper supply apparatus according to claim 2, wherein   4. The lift-side connecting gear is displaced in a direction approaching the driving-side connecting gear by the rotating force when rotating by obtaining power from the driving device. The paper supply apparatus according to any one of the above.   An image forming apparatus comprising the paper supply device according to claim 1.

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