JP2008001466A - Paper storage device and image forming device provided with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper storage device capable of certainly installing both side cursors even when a ground-contact member is provided on either one of a pair of side cursors or a pinion gear in the paper storage device using a width restriction mechanism constituted by a pair of side cursors made of metal and a conductive pinion gear for connecting these. <P>SOLUTION: An engagement hole 52e is provided on a slide part 52a in a width direction of the side cursor 52, and an engagement projection 28 is provided on a bottom wall 21 so as to be positioned at an inner side in a width direction relative to the engagement hole 52e. A tension coil spring 55 is extended so as to fasten these engagement hole 52e and engagement projection 28, and the side cursor 52 is always urged to the inner side in the width direction by the tension coil spring 55. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper storage device used in an image forming apparatus such as a copying machine, a facsimile, and a printer, and more particularly to a paper storage device provided with a width regulating mechanism that aligns the widthwise ends of the paper to be stored. Is.

  2. Description of the Related Art Conventionally, image forming apparatuses such as copying machines, facsimile machines, and printers are provided with a paper feed cassette that can accommodate a large number of sheets. A paper stacking plate is provided inside the paper feed cassette mounted in such an image forming apparatus. This sheet stacking plate is rotatably supported at both sides of the rear end in the paper feeding direction by the side wall of the paper feeding cassette, and biasing means such as a coil spring is provided on the lower surface of the front end in the paper feeding direction.

  When the front end of the paper stacking plate is biased upward, the stacked paper is automatically pushed up, and the uppermost paper stacked on the paper stacking plate can be pressed against the pickup roller and fed. It is configured as follows. Further, a separation means such as a separation pad or a retard roller is provided downstream of the pickup roller, so that the sheets stacked on the sheet stacking plate are fed into the apparatus main body one by one from the top. It is configured to be.

  However, in the paper feed cassette configured as described above, a charge is generated by friction between the uppermost sheet and the second sheet on the sheet stacking plate during sheet feeding, and the charge is transferred to the sheet stacking plate. Will be accumulated. The electric charge accumulated on the paper stacking plate is discharged to cause a malfunction of the control circuit in the main body of the apparatus, or when the user's finger touches the middle plate when replenishing paper, etc. There is a risk of giving.

  In view of this, a paper storage device has been proposed that makes it possible to drop the charge accumulated on the paper stacking plate into the main body device as described above, and prevents the malfunction of the control circuit and the electric shock of the user due to the discharge of the charge. For example, Patent Document 1 discloses a container unit that can store multiple sheets, a sheet stacking plate for stacking sheets in the container unit, and a container for contacting the sheet with a feeding unit. And a biasing means for biasing the paper stacking plate in the section, and a part of the biasing means is extended to the outer surface of the container portion, and the charge charged on the paper stacking plate is released by the extension portion. A containment device is disclosed.

  By the way, in recent years, universal cassettes capable of storing a plurality of paper sizes have been used, and the paper width regulating mechanism used in such a paper feed cassette is applied to a rack plate and paper provided with a rack gear. It comprises a pair of side cursors that are slidable in a direction perpendicular to the paper feeding direction in order to regulate the paper width, and a pinion gear connected to the rack gear.

  The rack gears of the rack plates of the side cursors are formed so as to face each other, and one rack gear is drivingly connected to the other rack gear via a pinion gear. By sliding in a perpendicular direction, the other side cursor slides by the same amount as the one side cursor in the direction opposite to the sliding direction of one side cursor around the pinion gear.

When the metal side cursor is used in the paper feeding cassette configured as described above, a charge is generated by friction between the paper and the side cursor conveyed during paper feeding, and the charge is transferred to the side cursor. The pinion gear is formed from a conductive material, and a pair of side cursors are electrically moved through the pinion gear, and a grounding member is provided on one of the side cursors. Thus, there has been proposed a universal cassette configured to release the electric charges charged in both side cursors.
Japanese Patent Laid-Open No. 11-222329

  However, when the grounding member is provided only on one side cursor as described above, and both side cursors are neutralized, the side cursor and pinion gear are caused by the backlash between the rack gear and the pinion gear of the side cursor. In some cases, a contact failure may occur between the two and a conduction failure. When the conduction failure occurs as described above, the static electricity charged on the side cursor may cause an abnormal operation to the image forming apparatus.

  In view of the above problems, the present invention provides a sheet storage device using a sheet width regulating unit including a pair of metal side cursors and a conductive pinion gear that connects the pair of metal side cursors. It is an object of the present invention to provide a paper storage device capable of reliably grounding both side cursors even when only one of them is provided with a grounding member.

  In order to achieve the above object, the present invention provides a housing for storing paper, a conductive pinion gear rotatably supported inside the bottom surface of the housing, and slides in the width direction along the bottom surface of the housing. A width regulating mechanism that is configured from a pair of metal side cursors provided with rack gears that are arranged so as to mesh with the pinion gears, and that aligns the widthwise ends of the paper stored in the housing; A grounding member is connected to either one of the side cursor or the pinion gear to release a charge charged to the side cursor, and at least of the pair of side cursors. One side cursor is provided with urging means for urging the side cursor inward in the width direction.

  According to the present invention, in the paper storage device configured as described above, the biasing means is a tension coil spring stretched so as to connect the side cursor and an engagement protrusion provided on a bottom surface of the housing. It is a feature.

  According to the present invention, in the paper storage device configured as described above, the grounding member is formed of a wire spring material, and a protruding portion for click is formed at a portion connected to the side cursor, The cursor is provided with an engaging portion that engages with the protruding portion.

  According to the present invention, in the image forming apparatus including the paper storage device having the above-described configuration, a conductive member is provided at a position in contact with the grounding member when the paper storage device is mounted.

  According to the first configuration of the present invention, the rack gear and the pinion gear provided on the metal side cursor are engaged by urging at least one of the metal side cursors inward in the width direction by the urging means. Even if there is backlash in the part, the metal side cursor will surely come into contact with the pinion gear, and there will be no contact failure between the metal side cursor and the pinion gear. The side cursor can be securely grounded, and the static electricity charged on the metal side cursor is prevented from causing an abnormal operation to the image forming apparatus. Further, by urging the metal side cursor inward in the width direction, the backlash of both metal side cursors is eliminated, paper alignment is stabilized, and registration accuracy is improved.

  According to the second configuration of the present invention, in the paper storage device of the first configuration, when the compression spring is used as the biasing means for the metal side cursor, the metal side cursor is positioned outside in the width direction. It is necessary to dispose a compression spring on the housing, which leads to an increase in the size of the housing of the paper storage device. However, since a tension coil spring can be disposed inside the metal side cursor in the width direction, the housing of the paper storage device No increase in size.

  According to the third configuration of the present invention, in the paper storage device having the first or second configuration, the engagement portion provided on the metal side cursor is set so that the metal side cursor has a standard size width of the paper. If it is provided at a position where it engages with the protrusion when it is slid to the corresponding position, the metal side cursor is moved by the click feeling due to the change in resistance before and after engaging with the engagement portion of the protrusion. It can be confirmed that the slider has been slid to a position corresponding to the standard size width, and the metal side cursor can be easily aligned.

  According to the fourth configuration of the present invention, in the image forming apparatus including the paper storage device having any one of the first to third configurations, when the paper storage device is mounted, it contacts the grounding member. By providing the conductive member at the position, the ground member is reliably grounded via the conductive member in a state where the sheet storage device is mounted on the image forming apparatus main body, and therefore, by static electricity charged on the metal side cursor, It is possible to prevent abnormal operation of the image forming apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram illustrating the overall configuration of an image forming apparatus including a paper feed cassette according to the present invention, and the right side is illustrated as the front side of the image forming apparatus. FIG. 2 is a perspective view showing a state in which the paper feed cassette is pulled out from the image forming apparatus main body. Here, in this embodiment, a printer is illustrated as an example of an image forming apparatus. However, it goes without saying that the present invention can be applied to an image forming apparatus other than a printer, such as a copying machine or a facsimile.

  First, the outline of the image forming apparatus 1 will be described with reference to FIG. In the image forming apparatus 1, when performing an image forming operation, the photosensitive drum 2 that rotates clockwise in the drawing is uniformly charged by the charging unit 3, and the exposure unit (laser scanning unit or the like) 4 based on the document image data. An electrostatic latent image is formed on the photosensitive drum 2 by the laser beam, and a developer (hereinafter referred to as toner) is attached to the electrostatic latent image by the developing unit 5 to form a toner image.

  The toner is supplied to the developing unit 5 from the toner container 6. The image data is transmitted from a personal computer (not shown) or the like. Further, a static elimination device (not shown) for removing residual charges on the surface of the photosensitive drum 2 is provided on the downstream side of the cleaning device 7.

  The sheet fed from the sheet feeding cassette 20 by the pickup roller 8 toward the photosensitive drum 2 on which the toner image is formed as described above, and being fed at the nip portion between the feed roller 9 and the retard roller 10 is supplied to the sheet. The toner image formed on the surface of the photosensitive drum 2 is transferred onto a sheet by the transfer roller 13 (image transfer unit) that is conveyed through the path 11 and the registration roller pair 12.

  The sheet on which the toner image is transferred is separated from the photosensitive drum 2 and conveyed to the fixing unit 14 having the fixing roller pair 14a to fix the toner image. The sheet that has passed through the fixing unit 14 is conveyed to the upper part of the apparatus by a sheet conveying path 15 and is discharged to a discharge tray 17 by a discharge roller pair 16.

  Here, in the lower part of the main body of the image forming apparatus 1, there is provided a space (hereinafter referred to as a “paper cassette mounting portion”) 1 a in which the paper feed cassette 20 that opens to the front surface of the main body of the image forming apparatus 1 is mounted. The paper cassette 20 is mounted in the paper cassette mounting portion 1a. To facilitate the paper replenishment operation to the paper cassette 20, the paper cassette 20 is pulled out in the direction of the arrow A, as shown in FIG. As shown, the image forming apparatus 1 is configured to be removable from the main body.

  Next, the paper feed cassette 20 according to the present embodiment will be described with reference to FIGS. FIG. 3 is a perspective view of the sheet feeding cassette as viewed from above. 4 is a perspective view of the paper feed cassette as seen from above, as in FIG. 3, but with the paper stacking plate excluded. 5 and 6 are perspective views of the side cursor disposed in the paper feed cassette. FIG. 5 illustrates the side cursor disposed on the right side in the paper transport direction. FIG. 6 illustrates the paper transport. The side cursor arrange | positioned on the left side toward the direction is shown in figure.

  As shown in FIG. 3, the paper feed cassette 20 includes a bottom wall 21, a pair of side walls 22 provided on both side edges of the bottom wall 21 so as to be perpendicular to the bottom wall 21, and the bottom wall 21. The rear wall 23 is provided at the rear end edge so as to be perpendicular to the bottom wall 21, and the cassette cover 24 is provided at the front end edge of the bottom wall 21 so as to be perpendicular to the bottom wall 21. Is configured. The cassette cover 24 is exposed to the outside when the paper feed cassette 20 is mounted on the main body of the image forming apparatus 1 so that the surface side (the side seen from the arrow B) is exposed to the outside. Part of it.

  Further, on the outer surfaces of the side walls 22, protrusions 25 extending in the mounting direction of the sheet feeding cassette 20 to the main body of the image forming apparatus 1 (direction of arrow C) are integrally formed. On the other hand, guide rails 1b (see FIG. 2) for guiding the protrusion 25 when the paper feed cassette 20 is attached and detached are disposed on both sides of the paper feed cassette mounting portion 1a of the image forming apparatus 1 main body. When the paper cassette 20 is mounted, the paper feed cassette 20 is guided to a predetermined position by the guide rail 1b.

  As shown in FIG. 3, a paper stacking plate 30 is provided inside the housing of the paper feed cassette 20 so as to be rotatably supported on both side walls 22 and on which paper is stacked. The sheet stacking plate 30 is integrally formed with a pair of engaging pieces 30b so as to be bent vertically upward on both side edges of the rear end in the sheet feeding direction of the mounting plate 30a on which sheets are stacked. By engaging the piece 30 b with a rotation fulcrum 26 provided on the inner surface of both side walls 22, the piece 30 b is rotatably supported with respect to the both side walls 22.

  In addition, notches are formed on both side edges and the rear edge of the mounting plate 30a, respectively, and when the sheet size to be stacked is small, a rear edge cursor 40 and side cursors 51 and 52, which will be described later, are fed. The paper cassette 20 can slide inward. Further, a compression coil spring (not shown) is disposed between the lower surface of the front end of the loading plate 30 a and the upper surface of the bottom wall 21, whereby the sheet stacking plate 30 is rotated about the rotation fulcrum 26. The paper loaded on the mounting plate 30a is pressed against the pickup roller 8.

  Further, a rear end cursor 40 that restricts the rear end of the stacked paper and a width restriction mechanism 50 that restricts the width direction end of the stacked paper are provided in the housing of the paper feed cassette 20. The trailing edge cursor 40 is slidably attached to the bottom wall 21 and a trailing edge regulating portion 40b that stands vertically from one end of the conveying direction sliding portion 40a and aligns the trailing edge of the paper. And is slidable in the paper transport direction along a guide rail 27 provided on the bottom wall 21.

  As shown in FIG. 4, the width regulating mechanism 50 includes a side cursor 51 that regulates the right end in the transport direction of the stacked paper and a side cursor that regulates the left end in the transport direction of the stacked paper. 52 and a pinion gear 53 which meshes with rack gears 51d and 52d provided on the side cursors 51 and 52 and drives and connects them.

  As shown in FIGS. 5 and 6, the side cursors 51, 52 are substantially L-shaped width direction sliding portions 51 a, 52 a that slide in the paper width direction along the bottom wall 21, and each width direction. It comprises rectangular width restricting portions 51b and 52b which are vertically arranged from one end of the sliding portions 51a and 52a and align the end portions in the width direction of the paper. Further, guide grooves 51c and 52c are provided in the respective width direction sliding portions 51a and 52a, and the reciprocating movement of the side cursors 51 and 52 is stable by engaging with the rib provided on the bottom wall 21. It has come to be.

  In addition, rack gears 51d and 52d that mesh with the pinion gear 53 are formed at the end edges of the respective width direction sliding portions 51a and 52a on the side in contact with the pinion gear 53. The side cursors 51 and 52 are disposed on the bottom wall 21 so that the rack gears 51d and 52d face each other and are connected to each other via a pinion gear 53. For example, the side cursors 51 and 52 are arranged in the paper width direction. When slid, the side cursor 52 slides by the same amount as the movement amount of the side cursor 51 in the direction opposite to the sliding direction of the side cursor 51 around the pinion gear 53.

  Further, the side cursor 51 is provided with a stopper (not shown) so that the side cursor 51 can be fixed by this stopper. When the side cursor 51 is fixed, the pinion gear 53 cannot be rotated. Therefore, the side cursor 52 is also fixed via the pinion gear 53.

  Here, in order to reliably regulate the side edges of the stacked sheets, the width regulating portions 51b and 52b of the side cursors 51 and 52 need to have a predetermined rigidity or more. In order to obtain sufficient rigidity when the 52 is formed from resin, it is necessary to form the width restricting portions 51b and 52b very thick, which leads to an increase in the size of the paper feed cassette 20, so that the side cursors 51 and 52 are It is made of a metal having sufficient rigidity.

  A grounding member 54 (see FIGS. 7 to 9) is connected to the side cursor 51 so that charges charged in the side cursor 51 can be released. Further, the pinion gear 53 is made of a conductive resin, whereby the side cursors 51 and 52 are brought into electrical conduction via the pinion gear 53, whereby only one grounding member 54 is provided. Thus, the electric charges charged in the side cursors 51 and 52 can be released.

  Here, the grounding member 54 will be described with reference to FIGS. FIG. 7 is a perspective view showing the grounding member disposed on the bottom wall of the sheet cassette, excluding the sheet stacking plate and the side cursor disposed on the right side in the sheet transport direction. . FIG. 8 illustrates a state in which the side cursor is disposed on the grounding member illustrated in FIG. FIG. 9 is a perspective view of the sheet cassette as viewed from below.

  The grounding member 54 is formed by bending a conductive wire spring material, and is provided on the side cursor side grounding portion 54a in contact with the side cursor 51 and the main body of the image forming apparatus 1 as shown in FIG. The body side grounding part 54b in contact with the conductive member 1c (see FIG. 2) is formed in series, and the side cursor side grounding part 54a and the body side grounding part 54b are formed in a substantially L shape in plan view so as to form a right angle. Has been. The grounding member 54 is disposed so that the side cursor side grounding portion 54a faces the paper width direction and the main body side grounding portion 54b faces the paper transport direction.

  When the side cursor 51 is disposed, the side cursor side grounding portion 54a comes into contact with the lower surface of the width direction sliding portion 51a of the side cursor 51 as shown in FIG. The side grounding portion 54 a is provided with a click protrusion 54 c that is bent so as to protrude vertically upward with respect to the bottom wall 21. A plurality of engaging portions 51e that engage with the protruding portions 54c are provided (see FIG. 5). These engaging portions 51e are provided at positions where the side cursor 51 is engaged with the protruding portion 54c when the side cursor 51 is slid to a position corresponding to the standard size width of the paper.

  When the protruding portion 54c is not engaged with the engaging portion 51e, the protruding portion 54c is pressed by the width direction sliding portion 51a and bent downward, but the protruding portion 54c is engaged with the engaging portion 51e. The projecting portion 54c engages with the engaging portion 51e without being pressed by the width-direction sliding portion 51a, so that the projecting portion 54c slides in the width direction before and after engaging with the engaging portion 51e. It can be confirmed that the side cursor 51 has been slid to the position corresponding to the standard size width of the paper by the click feeling due to the change of the slip resistance of the moving portion 51a.

  The main body side grounding part 54b is provided with a grounding projecting part 54d bent so as to project vertically downward with respect to the bottom wall 21, and the bottom wall 21 faces the projecting part 54d. Through-holes are formed at the positions where the protrusions 54d are formed, and as shown in FIG. A conductive member 1c (see FIG. 2) is attached to the lower part of the paper feed cassette mounting portion 1a formed in the main body of the image forming apparatus 1. When the paper feed cassette 20 is mounted, the protruding portion 54d is a wire spring. The urging force is configured to be pressed against the conductive member 1c.

  Here, if there is a backlash in the meshing portion between the rack gears 51d and 52d provided on the side cursors 51 and 52 and the pinion gear 53, the side cursor 52 will play back when the side cursor 51 is fixed by the stopper. In such a case, a contact failure may occur between the side cursor 52 and the pinion gear 53, and a conduction failure may occur. When the conduction failure occurs as described above, the static electricity charged on the side cursor 52 may cause an abnormal operation to the image forming apparatus 1.

  Therefore, as shown in FIG. 6, an engagement hole 52e is formed in the width direction sliding portion 52a of the side cursor 52, and as shown in FIG. 4, the bottom wall 21 is located in the width direction with respect to the engagement hole 52e. The engagement protrusion 28 is provided so as to be located in the direction, and the tension coil spring 55 is stretched so as to connect the engagement hole 52e and the engagement protrusion 28. The side cursor 52 is always widened by the tension coil spring 55. It is configured to be urged inward in the direction and reliably contact the pinion gear 53.

  As a result, no contact failure occurs between the side cursor 52 and the pinion gear 53, so that the side cursor 52 can be securely grounded, and the image forming apparatus 1 is charged with static electricity charged on the side cursor 52. In contrast, abnormal operation is prevented. Further, by biasing the side cursor 52 inward in the width direction, the side cursors 51 and 52 are not rattled, the sheet alignment is stabilized, and the registration accuracy is improved.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, the grounding member 54 is positioned on the right side in the paper transport direction. However, it may be provided on the left side cursor 52 or on the pinion gear 53. Moreover, in the said embodiment, although the grounding member 54 was formed from the wire spring material, this can also be formed from a leaf | plate spring etc.

  In the above-described embodiment, the left side cursor 52 is urged inward in the width direction by the tension coil spring 55. However, the tension coil spring 55 can be attached to the right side cursor 51. However, in that case, it is preferable to provide a stopper for fixing the side cursor on the side cursor 52. Furthermore, it is possible to provide tension coil springs 55 on both side cursors 51 and 52. As the biasing means, a compression coil spring, a torsion coil spring, or the like can be used in addition to the tension coil spring.

  INDUSTRIAL APPLICABILITY The present invention can be used in a paper storage device used in an image forming apparatus such as a copying machine, a facsimile machine, and a printer, and particularly has a paper storage provided with a width regulating means for aligning the widthwise ends of the stored paper. Can be used in the device.

FIG. 1 is a schematic configuration diagram illustrating an overall configuration of an image forming apparatus including a paper feed cassette according to the present invention. FIG. 4 is a schematic perspective view showing a state in which the paper feed cassette is pulled out from the image forming apparatus main body. FIG. 4 is an upper perspective view of the paper feed cassette. FIG. 4 is an upper perspective view of the paper feed cassette, excluding the paper stacking plate. FIG. 4 is a perspective view of a side cursor disposed on the right side in the transport direction. FIG. 5 is a perspective view of a side cursor disposed on the left side in the transport direction. FIG. 4 is a perspective view showing a grounding member disposed on the bottom wall of the paper feed cassette. These show the state where the side cursor is disposed on the grounding member. FIG. 4 is a lower perspective view of the paper feed cassette.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 1a Paper cassette mounting part 1b Guide rail 1c Conductive member 20 Paper feed cassette (paper accommodation apparatus)
21 bottom wall 22 side wall 23 rear wall 24 cassette cover 25 ridge 26 rotating fulcrum 27 guide rail 28 engaging protrusion 30 paper stacking plate 30a mounting plate 30b engaging piece 40 rear end cursor 40a transport direction sliding portion 40b rear end Restriction part 50 Width restriction mechanism 51, 52 Side cursor 51a, 52a Width direction sliding part 51b, 52b Width restriction part 51c, 52c Guide groove 51d, 52d Rack gear 51e Engagement part 52e Engagement hole 53 Pinion gear 54 Grounding member 54a Side Cursor side grounding part 54b Body side grounding part 54c Projection part 54d Projection part 55 Tension coil spring (biasing means)

Claims (4)

A housing for storing paper, a conductive pinion gear rotatably supported on the inner bottom surface of the housing, and slidably disposed in the width direction along the bottom surface of the housing, and meshes with the pinion gear In a paper storage device comprising: a pair of metal side cursors provided with a rack gear, and a width regulating mechanism for aligning the widthwise ends of the paper stored in the housing;
Either one of the side cursor or the pinion gear is connected to a grounding member for releasing the electric charge charged in the side cursor, and at least one of the pair of side cursors includes the ground cursor. A paper storage device comprising biasing means for biasing the side cursor inward in the width direction.   2. The paper storage device according to claim 1, wherein the biasing means is a tension coil spring stretched so as to connect the side cursor and an engagement protrusion provided on a bottom surface of the housing.   The grounding member is formed of a wire spring material, a click projection is formed at a portion connected to the side cursor, and the side cursor is engaged with the projection. The sheet storage device according to claim 1, wherein a section is provided.   An image comprising the paper storage device according to claim 1, wherein a conductive member is provided at a position in contact with the grounding member when the paper storage device is mounted. Forming equipment.

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