JP6018974B2 - Paper supply apparatus and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a sheet supply device suitably used for a copying machine, a printer, and the like, and an image forming apparatus including the same.

  2. Description of the Related Art Conventionally, a paper supply device having a detachable paper feed cassette is known.

  For example, Patent Literature 1 includes a pair of guide rails formed on the left and right side surfaces of a paper feed cassette that stores a bundle of sheets, and a pair of guide grooves formed in a main body case for guiding each guide rail. A paper supply apparatus is disclosed. Each guide rail is slidably engaged with each guide groove, and the paper feed cassette is pushed from the near side to the far side and attached to the main body case. The front end of each guide rail is formed with a tip portion that protrudes downward, and this tip portion comes into contact with the inclined surface of the step portion of each guide groove immediately before the mounting of the sheet feeding cassette is completed. The paper feed cassette is further pushed in from here, and the leading end of the paper feeds over the stepped portions to complete the mounting of the paper feed cassette.

  Further, for example, Patent Document 2 discloses a paper supply device including a driving roller provided in a main body case and a driven roller provided in a paper feed cassette. The driven roller is strongly urged by the driving roller in a state where the sheet cassette is mounted on the main body case. Then, by rotating the driving roller, the paper stored in the paper feed cassette is conveyed one by one by the cooperation of both rollers.

JP 2004-269111 A JP 2009-057178 A

  However, in the technique described in Patent Document 1, when the tip end portion of each guide rail starts to slidably contact the stepped portion of each guide groove, the load applied to pushing in the paper feed cassette suddenly increases. There was a problem that the increase was mistakenly recognized as the completion of the installation of the paper cassette. In particular, when the load fluctuation timing is immediately before the completion of mounting, that is, when the paper feed cassette is substantially closed, such a problem becomes more prominent. Thus, the image forming apparatus cannot be operated in a state where the mounting is incomplete, and the user is forced to perform a mounting operation again.

  Further, in the technique described in Patent Document 2, since the urging force of the driven roller acts as a repulsive force that pushes the paper feed cassette outward, a large load fluctuation occurs when the driven roller contacts the driving roller during mounting. Has occurred. Such a rapid load fluctuation applied when the paper cassette is pushed in causes a user to misrecognize the correct mounting position of the paper cassette.

  The present invention has been made to solve the above-described problems, and provides a paper supply device that can easily recognize that a paper feed cassette is mounted at a correct position, and an image forming apparatus including the paper supply device. The purpose is to do.

  In order to achieve the above-described object, a paper supply device according to the present invention is configured to be detachable from a main body case, and is urged toward a mounting direction of the paper supply cassette, and a paper supply cassette that stacks and stores paper. In this state, the paper transporting the sheet located on the outermost layer of the paper feed cassette toward the transport path by the cooperation of the first transport roller provided in the paper feed cassette and the second transport roller provided in the main body case. A mechanism, a sliding contact member provided in one of the main body case and the paper feed cassette and extending in the attaching / detaching direction of the paper feed cassette, and provided in either one of the main body case and the paper feed cassette. The sliding contact member is pressed against the sliding contact member when the first transport roller and the second transport roller are separated from each other in the process of attaching and detaching the paper feed cassette. Characterized in that it and a pressing member for relative sliding me.

  According to this configuration, for example, when the paper feed cassette is mounted on the main body case, the relative sliding of the pressing member pressed by the sliding contact member before the first transport roller and the second transport roller come into contact with each other. The movement starts. Therefore, the sliding resistance by the sliding contact member and the pressing member occurs before a large load fluctuation due to the contact between the rollers. For this reason, it is possible to gradually increase the load generated when the paper feed cassette is mounted on the main body case. This prevents sudden load fluctuations associated with the loading, and can effectively prevent the user from erroneously recognizing that the load fluctuation is the completion of the loading of the paper feed cassette.

  In this case, it is preferable that the front end surface of the pressing member is fixed at a position where the pressing surface can slide on the sliding contact member.

  According to this configuration, since the pressing member is fixed, it is possible to generate a stable sliding resistance with the sliding contact member with a simple configuration. As a result, it is possible to configure a paper supply device that can prevent sudden load fluctuations at low cost.

  In addition, the sliding contact member is formed in a rail shape having at least a part of an inclined surface that increases a pressing force with the pressing member toward the mounting direction of the paper feed cassette, The pressing member includes a rotating member that is rotatably provided so as to be in sliding contact with the sliding contact member including the inclined surface, and a biasing member that biases the rotating member toward the sliding contact member. It is preferable that it is comprised.

  According to this configuration, the rotating member urged by the urging member slides relatively along the inclined surface of the slidable contact member. The sliding resistance with the rotating member will gradually increase. Therefore, since the load applied to the mounting varies smoothly, it is possible to more appropriately prevent erroneous recognition of the mounting completion by the user, and to provide the user with good operability.

  In these cases, a mechanism-side sliding contact member provided in one of the main body case and the paper feed cassette and extending in the attachment / detachment direction of the paper feed cassette, and the other of the main body case and the paper feed cassette A pressing action position that slides on the mechanism side sliding contact member to apply a pressing force to the pressing member in the process of attaching and detaching the paper feeding cassette; and at least the mechanism side in a state where the paper feeding cassette is mounted A projecting mechanism-side pressing member that moves the sheet cassette between a pressing release position that releases the pressing force applied to the pressing member by releasing the sliding contact with the sliding contact member. It is preferable.

  According to this configuration, when the paper feed cassette is mounted at the correct position of the main body case, the pressure applied to the pressing member is released. Thereby, the user can easily recognize that the paper feed cassette is mounted at the correct position.

  In order to achieve the above object, an image forming apparatus according to the present invention includes any one of the above-described paper supply devices.

  According to this configuration, for example, when a paper cassette is mounted, sliding resistance due to the sliding contact member and the pressing member is generated before a large load fluctuation due to contact between the rollers. The generated load can be increased stepwise. This prevents sudden load fluctuations associated with the loading, and can effectively prevent the user from erroneously recognizing that the load fluctuation is the completion of the loading of the paper feed cassette.

  According to the present invention, it can be easily recognized that the paper feed cassette is mounted at the correct position.

1 is a perspective view showing a printer according to an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically illustrating the internal structure of the printer according to the embodiment of the invention. 1 is a perspective view showing a paper supply device according to an embodiment of the present invention. It is sectional drawing which shows the paper supply apparatus which concerns on one Embodiment of this invention. It is a perspective view showing a lock mechanism of a paper supply device according to an embodiment of the present invention. FIG. 3 is a perspective view showing a part of a main body case and a paper feed cassette of the paper supply device according to the embodiment of the present invention. It is a perspective view which shows the paper feed cassette of the paper supply apparatus which concerns on one Embodiment of this invention from another direction. It is sectional drawing which shows the state before mounting | wearing with the paper feed cassette of the paper supply apparatus which concerns on one Embodiment of this invention. It is sectional drawing which shows a mode that the paper feed cassette of the paper supply apparatus which concerns on one Embodiment of this invention moves to a press action position. It is sectional drawing which shows the state which the paper feed cassette of the paper supply apparatus which concerns on one Embodiment of this invention moved to the press release position. It is sectional drawing which shows the state before mounting | wearing with the paper feed cassette of the paper supply apparatus which concerns on the modification of one Embodiment of this invention.

  Hereinafter, a sheet supply device according to an embodiment of the present disclosure and a printer as an image forming apparatus including the same will be described with reference to the accompanying drawings. In the following description, for convenience, the arrow Fr shown in each figure is defined as the front side (front side) of the printer.

  First, the printer 1 will be described with reference to FIGS. 1 and 2. Here, FIG. 1 is a perspective view showing the printer 1, and FIG. 2 is a cross-sectional view schematically showing the internal structure thereof.

  As shown in FIGS. 1 and 2, the printer 1 includes a main device 3 built in a box-shaped device body 2, and a plurality of paper supply devices 4 having a paper feed cassette 21 that stores a sheet of paper S. , Including. The apparatus main body 2 is integrally provided with a single sheet supply device 4 (see FIG. 2).

  In FIG. 1, the right front portion of the apparatus main body 2 is formed in a substantially semi-cylindrical shape, and a liquid crystal display portion for displaying various messages, a numeric keypad directly operated by a user, and the like are provided on the upper surface thereof.

  As shown in FIG. 2, the main device 3 includes an image forming unit 6 that transfers the toner image on the photosensitive drum 11 onto the paper S sent from the paper supply device 4 to the conveyance path 5, and the toner image transferred onto the paper. A fixing device 7 for fixing the toner image, and a paper discharge unit 8 as a discharge destination of the paper on which the toner image is fixed.

  The image forming unit 6 performs, for example, a monochrome image forming process, and includes a toner container 10 that stores a supply toner (black (K)). In addition, the image forming unit 6 forms an electrostatic latent image by exposing the surface of the photosensitive drum 11, the photosensitive drum 11 that carries the toner image, the charger 12 that charges the surface of the photosensitive drum 11, and the surface of the photosensitive drum 11. An exposure unit 13, a developing unit 14 that develops the electrostatic latent image into a toner image with toner, a transfer roller 15 that transfers the toner image onto the paper S in cooperation with the photosensitive drum 11, and a photosensitive drum after transfer. 11 and a cleaning device 16 that removes toner remaining on the surface.

  The charging device 12, the exposure device 13, the developing device 14, the transfer roller 15, and the cleaning device 16 are arranged in the order of the transfer process along the rotation direction of the photosensitive drum 11.

  Here, an image forming operation by the printer 1 will be described. When the printer 1 is turned on, initialization of various parameters such as temperature setting of the fixing device 7 is executed. Then, when image data is input from a personal computer (not shown) connected to the printer 1 and an instruction to start printing is given, an image forming operation is executed as follows.

  First, exposure according to image data is performed by the exposure device 13 on the surface of the photosensitive drum 11 charged to a predetermined potential by the charger 12. As a result, the electrostatic latent image formed on the photosensitive drum 11 is developed into a toner image by the developing device 14. Then, a transfer bias is applied to the transfer roller 15, and the toner image is transferred to the paper S that has been transported through the transport path 5. The transferred toner image is fixed on the paper S by the fixing device 7. The sheet S on which the toner image is fixed is conveyed downstream and discharged to the sheet discharge unit 8. Further, after the transfer is completed, the toner remaining on the surface of the photosensitive drum 11 is removed by the cleaning device 16.

  Next, each paper supply device 4 will be described with reference to FIGS. Here, FIG. 3 is a perspective view showing the paper supply device 4, and FIG. 4 is a sectional view thereof. FIG. 5 is a perspective view showing the lock mechanism 35 of the paper supply device 4. FIG. 6 is a perspective view showing a part of the main body case 20 of the paper supply device 4 and the paper feed cassette 21.

  In the present embodiment, for example, one sheet supply device 4 provided integrally with the apparatus main body 2 and four sheet supply devices 4 as additional options are stacked in the vertical direction. The device main body 2 containing the main device 3 is arranged at the top (see FIG. 1). The five paper feed cassettes 21 are configured to be able to accommodate different sizes of paper S, respectively. The paper S includes various recording media such as plain paper, high-quality paper, coated paper, cardboard, and an OHP sheet (including those other than paper).

  As shown in FIG. 3, each paper supply device 4 includes a main body case 20 that forms a main appearance, and a paper feed cassette 21 that is configured to be detachable from the main body case 20 and that stores paper S in a stacked manner. It is formed in a substantially flat rectangular parallelepiped shape. Here, since each paper supply device 4 has substantially the same configuration, one paper supply device 4 will be described in detail below. In the following description, for the sake of convenience, the left-right direction is also referred to as “width direction”, the front side is also referred to as “front side”, and the rear side is also referred to as “back side”.

  As shown in FIGS. 3 to 6, the paper supply device 4 conveys the pickup roller 22 in contact with the paper S located on the outermost layer of the paper feeding cassette 21 and the paper S drawn by the pickup roller 22 one by one. Separating mechanism 23, conveying mechanism 24 for sending the sheet S sent by the separating mechanism 23 toward the conveying path 5, and sliding contact provided in the sheet feeding cassette 21 and extending in the attaching / detaching direction of the sheet feeding cassette 21. A pair of left and right members 25, a pressing member 26 provided in the main body case 20, which slides relatively along the sliding contact member 25, and a left and right pair provided in the main body case 20 and extending in the attaching / detaching direction of the paper feed cassette 21. A mechanism-side sliding contact member 27 (see FIG. 8) and a pair of left and right mechanism-side pressing members 28 (see FIG. 8) provided in the paper feed cassette 21 and capable of sliding contact with the mechanism-side sliding contact member 27 are provided. Yes.

  As shown in FIG. 5, the main body case 20 is formed in a box shape having an opening 20a on the front end surface. On the upper surface of the main body case 20, a pair of connecting protrusions 30 project from substantially the center in the front-rear direction of both left and right ends. Each connection protrusion 30 is adapted to be fitted into a recess (not shown) formed on the bottom surface of the paper supply device 4 and the device main body 2 placed on the main body case 20. Thus, the plurality of paper supply devices 4 and the device main body 2 are stacked in a positioned state. In FIG. 5, a connector 20b is provided on the rear side of the right connecting projection 30 so as to be electrically connected to the upper device during lamination. A pair of slide rails 31 are formed on the left and right inner surfaces of the main body case 20 (see FIG. 8).

  As shown in FIGS. 3, 4, and 6, the paper feed cassette 21 includes a design surface 32 provided on the front side, a mechanism holding unit 33 provided on the back side of the design surface 32, and a back surface of the mechanism holding unit 33. And a base portion 34 provided on the side. The paper feed cassette 21 is inserted into the main body case 20 through the opening 20 a and is supported so as to be slidable in the front-rear direction with respect to the main body case 20.

  In FIG. 3, the right side of the design surface 32 is formed in a substantially semi-cylindrical shape like the right front portion of the apparatus main body 2. The design surface 32 is exposed to the front surface in a state in which the paper feed cassette 21 is mounted on the main body case 20, and forms substantially the same surface as the front surface of the apparatus main body 2 (see FIG. 1).

  As shown in FIG. 6, the mechanism holding portion 33 is connected to a portion excluding the substantially semi-cylindrical shape formed on the right side of the design surface 32. The mechanism holding portion 33 is formed with an apparatus-side conveyance path 33a that penetrates in the vertical direction (see FIG. 4). Further, a lock mechanism 35 is provided on the front side of the mechanism holding portion 33.

  As shown in FIG. 5, the lock mechanism 35 includes a pair of left and right hooks 36 that are engaged with holes (not shown) formed in the left and right side walls of the main body case 20, and triangular right and left connected to the hooks 36. A pair of rotating plates 37, a pair of left and right lock springs 38 that urge each hook 36 outward in the width direction, and an operation unit 39 that is held by a user to perform a lock release operation.

  Each hook 36 is formed in a plate shape that is long in the width direction of the paper feed cassette 21. A receiving hole 36 a that is long in the front-rear direction is formed through the center of each hook 36 in the width direction.

  Each rotation plate 37 is arranged with the hypotenuse toward the center in the width direction, and is supported by the mechanism holding portion 33 so as to rotate about a lock rotation shaft 37a provided at a substantially center of gravity. Each rotation plate 37 is rotatably connected to the hook 36 at the top on the back side, and is slidably connected to the end in the width direction of the operation unit 39 at the top on the near side.

  The operation unit 39 is disposed on the back surface slightly to the left of the design surface 32 in the width direction, and is provided to be slidable in the front-rear direction. An operation spring 39 a that urges the operation unit 39 toward the back side is attached to the center of the operation unit 39 in the width direction.

  When the paper cassette 21 is pulled out, the user pulls the operation unit 39 toward the front side. Then, the left and right rotation plates 37 rotate inwardly about the lock rotation shaft 37a. Each hook 36 moves toward the center in the width direction against the urging force of the lock spring 38. As a result, the tip of each hook 36 is detached from each hole of the main body case 20, and the paper feed cassette 21 can be pulled out from the main body case 20.

  On the other hand, when the paper cassette 21 is pushed in (attached), when the paper cassette 21 is moved toward the back side, the operation unit 39 is moved to the back side by the operation spring 39a, and the left and right rotating plates 37 are respectively Rotate outward. Each hook 36 moves toward the outside in the width direction (direction away from the center line) by the urging force of the lock spring 38. As a result, the tip of each hook 36 engages with each hole of the main body case 20, and the paper feed cassette 21 is locked so that it cannot be pulled out from the main body case 20.

  As shown in FIGS. 4 and 6, the base portion 34 is formed to extend rearward from the back surface of the mechanism holding portion 33. That is, the base portion 34 is connected to the portion excluding the substantially semi-cylindrical shape formed on the right side of the design surface 32 via the mechanism holding portion 33.

  The base portion 34 includes a bottom plate portion 40 that supports a paper stacking portion 42 on which the paper S is placed (laminated), a pair of side wall portions 41 that are provided upward from both left and right end portions of the bottom plate portion 40, and Are integrally formed.

  The sheet stacking unit 42 is pivotally supported by a push-up rotation shaft 42a provided on the rear end side. Further, a push-up spring 42b that urges the sheet stacking portion 42 upward with the bottom plate portion 40 as a base is disposed below the front end of the sheet stacking portion 42 (see FIG. 2).

  As shown in FIG. 6, a pair of left and right lateral guides 42c are provided on the front side of the sheet stacking portion 42 so as to be slidable in the left-right direction, and a longitudinal guide 42d is provided on the rear portion of the bottom plate portion 40 so as to be slidable in the front-rear direction. It has been. When the paper S is set at a predetermined position of the paper stacking unit 42, the front end of the paper S is brought into contact with the mechanism holding unit 33, and the pair of left and right horizontal guides 42c and 42d are slid to the left and right ends and the rear of the paper S, respectively. Touch to the end.

  The front end of each side wall portion 41 is connected to the mechanism holding portion 33. Slide grooves 43 extend in the front-rear direction at the outer lower portions of the side wall portions 41, respectively. When the slide rail 31 is slidably engaged with the pair of left and right slide grooves 43, the paper feed cassette 21 is slidably supported by the main body case 20 (see FIG. 8).

  In FIG. 6, the right side wall 41 is erected to a height that is substantially half of the design surface 32. On the other hand, the left side wall part 41 is erected up to a lower wall part 41a located at the rear side and formed at the same height as the right side wall part 41, and to a height of about 2/3 of the design surface 32 located at the front side. The high wall portion 41b and the inclined wall portion 41c that connects the low wall portion 41a and the high wall portion 41b are integrally formed (see FIG. 8). The upper end surfaces of the low wall portion 41a and the high wall portion 41b are respectively formed horizontally in the front-rear direction, and the upper end surface of the inclined wall portion 41c is formed to be inclined upward toward the front. Note that the inclined wall portion 41c may be omitted, and the low wall portion 41a and the high wall portion 41b may be connected.

  As shown in FIGS. 2 and 4, the pickup roller 22 is supported by the main body case 20 so as to be rotatable about a shaft extending in the width direction at a position facing the front end portion of the lifted sheet stacking portion 42. ing. For this reason, the uppermost (outermost) sheet S placed on the sheet stacking unit 42 is urged by the push-up spring 42 b and pressed against the pickup roller 22. Further, the pickup roller 22 rotates in the direction of the arrow in FIG.

  As shown in FIG. 2, the drive mechanism 44 includes a motor 44a, a clutch 44b, a gear train (not shown), and the like, and is disposed on the right side of the main body case 20 in FIG. The drive mechanism 44 receives a control signal from a control unit (not shown), and drives / stops the motor 44a and switches on / off the clutch 44b.

  The separation mechanism 23 includes a feed roller 45 provided in the main body case 20 in front of the pickup roller 22, a retard roller 46 provided in the mechanism holding portion 33 of the paper feed cassette 21 at a position facing the lower side of the feed roller 45, have.

  Each of the rollers 45 and 46 is supported so as to be rotatable about an axis parallel to the pickup roller 22, and is rotated in the direction of the solid line arrow in FIG. 4 by the driving force from the driving mechanism 44.

  The retard roller 46 is biased obliquely rearward by the separation spring 46 a and is pressed against the feed roller 45. Moreover, the retard roller 46 has a built-in torque limiter (not shown) that cuts off the driving force from the driving mechanism 44 when the load on the outer peripheral surface exceeds the set critical value.

  The transport mechanism 24 is provided in the mechanism holding portion 33 of the paper feed cassette 21 at a position facing the drive transport roller 47 (second transport roller) provided at the upper front end of the main body case 20 from the front side of the drive transport roller 47. And a driven transport roller 48 (first transport roller).

  Each of the transport rollers 47 and 48 is supported so as to be rotatable about an axis parallel to the pickup roller 22. The drive conveyance roller 47 is rotated in the direction of the solid line arrow in FIG. 4 by the drive force from the drive mechanism 44. The driven conveyance roller 48 is pressed by the driving conveyance roller 47 by the urging force of the conveyance spring 48a and is driven to rotate. That is, the driven transport roller 48 is provided in the paper feed cassette 21 in a state where it is urged toward the mounting direction of the paper feed cassette 21.

  Here, the conveyance of the sheet S positioned on the uppermost layer placed in the sheet feeding cassette 21 will be described. Here, as an initial state, it is assumed that the clutch 44b of the drive mechanism 44 is switched off, the motor 44a is stopped, and the rollers 22, 45 to 47 are stopped.

  When transporting the paper S, the clutch 44b is switched on. Thereby, the driving force of the motor 44a is transmitted to each roller 22, 45-47, and each roller 22, 45-47 rotates in a predetermined direction, respectively. When the sheet S 1 comes into contact with the rotating pickup roller 22, the sheet S is pulled out from the sheet stacking unit 42 and sent to the separation mechanism 23.

  When only one sheet S is sent between the feed roller 45 and the retard roller 46, the sheet S is sent to the supply path 49 by contacting the feed roller 45. At this time, the retard roller 46 receives a load exceeding the set limit value of the torque limiter from the feed roller 45 via the paper S, and therefore does not rotate in the direction of the solid line arrow in FIG. And rotate in the direction of the broken arrow in FIG.

  The sheet S sent to the supply path 49 passes between the driving conveyance roller 47 and the driven conveyance roller 48 and is supplied to the conveyance path 5 (or the apparatus-side conveyance path 33a of the sheet supply apparatus 4 disposed on the upper side). The The sheet S supplied to the apparatus-side conveyance path 33a is further conveyed upward by the conveyance mechanism 24 provided at the downstream end of the apparatus-side conveyance path 33a (see FIG. 2). That is, the paper S positioned at the outermost layer of the paper feed cassette 21 (paper stacking unit 42) is sent out toward the transport path 5 by the cooperation of the driving transport roller 47 and the driven transport roller 48.

  On the other hand, when two or more sheets S are double-fed between the feed roller 45 and the retard roller 46, the uppermost sheet S passes through the supply path 49 (the apparatus side) through the supply path 49 as described above. Transported to transport path 33a). At this time, the load applied to the retard roller 46 is reduced due to the presence of the lowermost sheet S, and the retard roller 46 continues to rotate in the direction of the solid arrow in FIG. For this reason, the lowermost sheet S is not sent to the supply path 49 due to the rotation of the retard roller 46. That is, the separation mechanism 23 separates two or more sheets S by cooperation of the feed roller 45 and the retard roller 46 to prevent double feeding.

  When the paper S passes through the separation mechanism 23, the clutch 44b is switched off, and the rotation of the rollers 22, 45 to 47 is stopped. Thereafter, when an image is formed on the second sheet S, the clutch 44b is turned on at a predetermined timing, and the conveyance of the sheet S is started again.

  Next, the sliding contact member 25 and the pressing member 26 will be described with reference to FIGS. FIG. 7 is a perspective view showing the paper feeding cassette 21 of the paper feeding device 4 from below. FIG. 8 is a cross-sectional view showing a state before the paper feed cassette 21 is mounted.

  The sliding contact member 25 is formed as the upper end surface of the left side wall 41 in FIG. Specifically, the sliding contact member 25 is formed in a rail shape by the upper end surface 50 of the high wall portion 41b.

  The pressing member 26 is formed on the upper left inner surface of the main body case 20 in FIG. 6 so as to face the sliding contact member 25 from above. More specifically, a rail portion 51 having a convex portion 51a that protrudes in a cantilever shape from the left inner surface of the main body case 20 inward and forms a crank shape downward is formed. The pressing member 26 protrudes further downward from the front end portion of the convex portion 51a. The front end (lower end) surface of the pressing member 26 is fixed to a position where the pressing member 26 can slide on the sliding contact member 25. The pressing member 26 is relatively moved along the sliding contact member 25 while being pressed by the sliding contact member 25 when the driving transport roller 47 and the driven transport roller 48 are separated from each other in the process of attaching and detaching the paper feed cassette 21. It is provided to slide.

  Next, each mechanism-side sliding member 27 and each mechanism-side pressing member 28 will be described with reference to FIGS.

  As shown in FIG. 8, each mechanism-side slidable contact member 27 is formed at the lower part of both left and right ends in the vicinity of the opening 20 a of the main body case 20. At the front end of each mechanism-side sliding contact member 27, a mechanism-side inclined surface 27a that tilts upward toward the rear is formed, and at the upper end of the mechanism-side inclined surface 27a, a mechanism-side slide that extends horizontally toward the rear. A contact surface 27b is formed. Further, the rear end of each mechanism-side sliding contact member 27 is formed vertically, and each mechanism-side sliding contact member 27 is formed in a substantially trapezoidal shape when viewed from the side.

  As shown in FIGS. 7 and 8, each mechanism-side pressing member 28 is formed so as to slightly protrude downward from the front lower end surface of the pair of left and right side wall portions 41. Each mechanism-side pressing member 28 is mounted with a pressing action position P1 at which the pressing force is applied to the pressing member 26 by slidingly contacting the mechanism-side sliding contact member 27 in the process of attaching and detaching the sheet feeding cassette 21. In this state, the sheet feeding cassette 21 is moved between the pressing release position P2 where the sliding contact with each mechanism side sliding contact member 27 is released and the pressing force applied to the pressing member 26 is released.

  Next, with reference to FIGS. 9 and 10, a process of attaching and detaching the paper feed cassette 21 to the main body case 20 will be described. Here, FIG. 9 is a cross-sectional view showing a state where the paper feed cassette 21 of the paper supply device 4 is moved to the pressing action position, and FIG. 10 is a cross-sectional view showing a state where it is moved to the press releasing position P2.

  First, a process in which the paper feeding cassette 21 is pushed in and attached from a state where it is pulled out from the main body case 20 will be described. When the user pushes the paper feed cassette 21 facing the pressing release position P2 toward the back side, the paper feed cassette 21 moves rearward along a pair of left and right slide rails 31. At this time, the positional relationship between the pressing member 26 and the sliding contact member 25 in the vertical direction does not come into contact with each other.

  As the user pushes in the paper feeding cassette 21, each mechanism-side pressing member 28 comes into contact with the mechanism-side inclined surface 27 a of each mechanism-side sliding contact member 27. At this time, the pressing member 26 is relatively moved to face the rear end side upper side of the sliding contact member 25 (upper end surface 50).

  When the paper cassette 21 is further pushed, each mechanism-side pressing member 28 slides on the mechanism-side inclined surface 27a and starts to contact the mechanism-side sliding contact surface 27b. Then, the entire sheet cassette 21 is lifted by the height of each mechanism-side pressing member 28, and the pressing member 26 is pressed against the rear end portion of the sliding contact member 25 (see FIG. 9). That is, the paper feed cassette 21 moves to the pressing action position P1. As a result, the load required to push the paper cassette 21 increases.

  In this state, when the paper feeding cassette 21 is further pushed in, the driven conveyance roller 48 comes into contact with the driving conveyance roller 47. As described above, the driven conveyance roller 48 is urged toward the driving conveyance roller 47 by the conveyance spring 48a, so that the load applied to the pushing is further increased.

  In this state, when the user pushes in the paper feed cassette 21, each mechanism-side pressing member 28 that has slid on each mechanism-side sliding contact surface 27 b gets over each mechanism-side sliding contact member 27, and each mechanism-side pressing member 28. The entire sheet feeding cassette 21 moves downward by the height (see FIG. 10). Thereby, the pressing member 26 is slightly separated upward from the sliding contact member 25. That is, the paper feed cassette 21 moves to the press release position P2. At this time, each lock mechanism 35 described above is in a locked state. As described above, the paper feed cassette 21 is attached to the main body case 20.

  In addition, before the driven conveyance roller 48 contacts the driving conveyance roller 47, the arrangement positions (heights) of the sliding contact member 25 and the pressing member 26 are set so that the pressing member 26 can contact the sliding contact member 25. And the length in the front-rear direction is set. Similarly, the arrangement positions (heights of the mechanism-side sliding members 27 and the mechanism-side pressing members 28 are set so that the members 25 and 26 can abut before the rollers 46 and 47 abut. And the length in the front-rear direction is set.

  Specifically, the pressing of the pressing member 26 against the sliding contact member 25 is started (feeding) in a state where the user can clearly recognize that the paper cassette 21 has not been mounted (the pressing is insufficient). It is preferable that the paper cassette 21 is moved to the pressing action position P1. For example, it is preferable that the paper feed cassette 21 is moved to the pressing action position P1 in a state where the paper S set in the paper feed cassette 21 is opened to the extent that the user can see from above.

  Next, when pulling out the paper feed cassette 21 from the main body case 20, the user unlocks each lock mechanism 35 according to the procedure described above, and pulls out the paper feed cassette 21 toward the front side. At this time, each mechanism-side pressing member 28 is in a state of being caught on the rear end surface of each mechanism-side slidable contact member 27. However, since the protruding amount of each mechanism-side pressing member 28 is small, the paper cassette 21 is pulled out. Does not interfere with operation. Then, in the reverse order of the mounting process described above, the sheet feeding cassette 21 is moved and pulled out between the pressing action position P1 and the pressing release position P2.

  According to the above-described paper supply device 4 according to the present embodiment, for example, when the paper feed cassette 21 is attached to the main body case 20, the sliding contact member is brought into contact with the drive conveyance roller 47 and the driven conveyance roller 48. The relative sliding of the pressing member 26 pressed by 25 is started. Therefore, the sliding resistance by the sliding contact member 25 and the pressing member 26 occurs before a large load fluctuation due to the contact between the rollers 46 and 47. For this reason, the load generated when the paper cassette 21 is attached to the main body case 20 can be increased stepwise. This prevents sudden load fluctuations associated with the loading, and can effectively prevent the user from erroneously recognizing the load fluctuations as the loading of the paper feed cassette 21 being completed.

  Further, according to the paper supply device 4 according to the present embodiment, since the pressing member 26 is fixed, it is possible to generate a stable sliding resistance with the sliding contact member 25 with a simple configuration. Thereby, the paper supply device 4 capable of preventing a sudden load fluctuation can be configured at a low cost. Further, when the paper feed cassette 21 is mounted at the correct position of the main body case 20, the pressure applied to the pressing member 26 is released. Thereby, the user can easily recognize that the paper feed cassette 21 is mounted at the correct position.

  Next, a modified example of the paper supply device 4 according to the present embodiment will be described with reference to FIG. Here, FIG. 11 is a cross-sectional view showing a state before the paper feeding cassette 21 of the paper feeding device 4 is mounted. Hereinafter, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the paper supply device 4 according to this modification, the sliding contact member 60 is formed in a rail shape from the inclined surface 61 as the upper end surface of the inclined wall portion 41c to the upper end surface 50 of the high wall portion 41b. As described above, the inclined surface 61 is formed to be inclined upward toward the front.

  Further, the pressing member 62 is provided so as to be rotatable so as to be in sliding contact with the sliding contact member 60 including the inclined surface 61, and a biasing force that biases the rotating member 63 toward the sliding contact member 60. The member 64 is comprised.

  The rotating member 63 is supported by the left inner wall of the main body case 20 in a state where the rotating member 63 can rotate around a pressing rotation shaft 65 provided at the front end thereof. A contact portion 66 protruding downward is formed at the rear end portion of the rotating member 63.

  The urging member 64 is a so-called coil spring, and is provided with an upper end fixed to a pedestal portion 67 formed on the lower surface of the rail portion 51 and a lower end fixed to the opposite side of the contact portion 66.

  Next, a process for attaching and detaching the paper feed cassette 21 to the main body case 20 will be described.

  The user pushes in the paper feed cassette 21 facing the pressure release position P <b> 2 and moves the paper feed cassette 21 rearward along each slide rail 31. Then, the rotation member 63 is urged by the urging member 64 and is rotated by the pressing rotation shaft 65 as a fulcrum and is pressed against the inclined surface 61. For this reason, a pushing load is applied to the sheet feeding cassette 21.

  As the user pushes in the paper feed cassette 21, the rotating member 63 slides relatively on the inclined surface 61. With this relative sliding, the pressing force against the inclined surface 61 of the rotating member 63 gradually increases. That is, the inclined surface 61 increases the pressing force with the pressing member 62 in the mounting direction of the paper feed cassette 21.

  Eventually, when each mechanism-side pressing member 28 starts to slide on each mechanism-side slidable contact member 27, the entire sheet feeding cassette 21 is lifted by the height of each mechanism-side pressing member 28, and the rotation member 63 is inclined. The pressing force against the surface 61 is further increased. When the paper cassette 21 is further pushed, the rotating member 63 starts to slide relative to the upper end surface 50, and the pressing force of the rotating member 63 against the upper end surface 50 becomes substantially constant. After that, when the driven conveyance roller 48 comes into contact with the driving conveyance roller 47 and the load applied to the push-in increases further, and the user pushes in the sheet feeding cassette 21, the sheet feeding cassette is inserted into the main body case 20 in the same manner as the above-described embodiment. 21 is attached.

  According to the paper supply device 4 according to the modification of the present embodiment described above, the rotating member 63 biased by the biasing member 64 slides relatively along the inclined surface 61 of the sliding contact member 25. Therefore, for example, when the paper feed cassette 21 is mounted, the sliding resistance between the sliding contact member 25 and the rotating member 63 gradually increases. Therefore, since the load applied to the mounting varies smoothly, it is possible to more appropriately prevent erroneous recognition of the mounting completion by the user, and to provide the user with good operability.

  In the paper supply device 4 according to the present embodiment and its modification, the sliding contact member 25 is provided in the paper feed cassette 21 and the pressing member 26 is provided in the main body case 20. The member 25 may be provided, and the pressing member 26 may be provided on the paper feed cassette 21. Further, although the members 25 and 26 are provided only on the left side in FIG. 6, they may be provided on the right side or on both the left and right sides.

  The inclined surface 61 of the inclined wall portion 41c only needs to constitute at least a part of the sliding contact member 25. That is, the longitudinal length and the inclination angle of the inclined surface 61 are arbitrarily set. For example, all of the sliding contact members 25 may be configured by the inclined surface 61. When the slidable contact member 25 is mainly composed of an inclined surface, the pressing force can be smoothly changed not only with the pressing member 62 according to the modified example but also with the fixed protruding pressing member 26. Furthermore, in the modification of this embodiment, although it was the linear inclined surface 61, it is not limited to this, For example, you may form in the parabolic shape (curved surface) which protrudes upwards or downwards.

  Note that the mechanism-side pressing member 28 and the mechanism-side slidable contact member 27 may be omitted in the paper supply device 4 according to the present embodiment and its modification. In this case, the pressing members 26 and 62 are arranged with dimensions such that they slide on the sliding contact members 25 and 60 with a predetermined pressing force.

  Further, in the paper supply device 4 according to the present embodiment and the modification thereof, the mechanism-side pressing member 28 and the mechanism-side sliding contact member 27 are provided separately from the sliding contact members 25 and 60 and the pressing members 26 and 62. However, the sliding contact members 25 and 60 may be used as the mechanism-side sliding contact member 27 and the pressing members 26 and 62 may be used as the mechanism-side pressing member 28. For example, the pressing members 26 and 62 are configured to slide on the sliding contact members 25 and 60 with a predetermined pressing force, and when the mounting of the paper feed cassette 21 is completed, the tips of the pressing members 26 and 62 are moved. The fitting recess may be provided on the sliding contact members 25 and 60.

  Note that the description of the present embodiment (including the modified example) describes a preferred embodiment in the printer 1 including the paper supply device 4 according to the present invention, and therefore various technically preferable limitations are attached. However, the technical scope of the present invention is not limited to these embodiments unless specifically described to limit the present invention. Furthermore, the constituent elements in the present embodiment can be appropriately replaced with the existing constituent elements and the like, and various variations including combinations with other existing constituent elements are possible. The description does not limit the content of the invention described in the claims.

1 Printer (image forming device)
DESCRIPTION OF SYMBOLS 4 Paper supply apparatus 5 Conveyance path 20 Main body case 21 Paper feed cassette 24 Conveyance mechanism 25,60 Sliding contact member 26,62 Pressing member 27 Mechanism side sliding contact member 28 Mechanism side pressing member 33a Apparatus side conveyance path 47 Drive conveyance roller (first) (2 transport rollers)
48 Followed transport roller (first transport roller)
61 Inclined surface 63 Rotating member 64 Biasing member P1 Pressing action position P2 Pressing release position S Paper

Claims (3)

A paper feed cassette configured to be detachable from the main body case, and stacking and accommodating paper;
The outermost layer of the paper feed cassette by the cooperation of the first transport roller provided in the paper feed cassette and the second transport roller provided in the main body case in a state of being biased toward the mounting direction of the paper feed cassette. A transport mechanism that sends out the paper located at the transport path toward the transport path;
A sliding contact member provided on one of the main body case and the paper feed cassette and extending in the attachment / detachment direction of the paper feed cassette;
It is provided on either the main body case or the paper feed cassette, and is pressed by the sliding contact member when the first transport roller and the second transport roller are separated in the process of attaching and detaching the paper feed cassette. A pressing member that slides relatively along the sliding contact member in a
A mechanism side sliding contact member provided in one of the main body case and the paper feed cassette and extending in the attaching / detaching direction of the paper feed cassette;
A protruding mechanism side pressing member provided on the other of the main body case and the paper feed cassette ,
The sliding contact member is formed in a rail shape having at least a part of an inclined surface such that a pressing force between the pressing member and the pressing member increases in a mounting direction of the sheet feeding cassette.
The pressing member is
A rotating member that is rotatably provided so as to be in sliding contact with the sliding contact member including the inclined surface;
A biasing member that biases the rotating member toward the sliding contact member,
The mechanism-side pressing member has a pressing action position in which a pressing force is applied to the pressing member by slidingly contacting the mechanism-side sliding contact member in the process of attaching and detaching the paper feeding cassette, and in the state where the paper feeding cassette is mounted. The paper cassette is moved between a press release position that releases the pressing force applied to the pressing member by releasing the sliding contact with the mechanism side sliding contact member,
The rotating member that is in sliding contact with the sliding contact member presses the paper feeding cassette downward,
The sheet feeding device according to claim 1, wherein the mechanism-side pressing member that is in sliding contact with the mechanism-side sliding member presses the sheet feeding cassette upward . As the mounting of the paper feeding cassette proceeds with respect to the main body case, the pressing force against the inclined surface of the rotating member gradually increases,
If the mechanism-side pressing member starts to slidably contact the mechanism-side slidable member after the rotating member slidably contacts the inclined surface, the pressing force of the rotating member against the inclined surface further increases. The paper supply device according to claim 1. An image forming apparatus characterized by comprising a sheet feeder according to claim 1 or 2.

Images