Sheet conveyance device, image reading device and image forming device

Abstract

To suppress the generation of loading failures of discharged sheets, in a sheet conveyance device which includes a loading tray stretchable in the width direction.SOLUTION: A document tray 4 of an ADF 2 includes: a first support member 41 for supporting a sheet; and a second support member movable between a drawn position and a retreat position with respect to the first support member 41. Furthermore, the document tray 4 includes: a first static elimination member 47 arranged at a bottom surface 45a of a first cover member 45; and a second static elimination member 48 arranged at a bottom surface 46a of a second cover member 46. The second static elimination member 48 is drawn out of the first support member 41 according to the movement of the second support member 42.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a sheet conveying device that conveys a sheet, an image reading device that reads image information from a sheet, and an image forming apparatus that forms an image on a recording material. [Background technology]

[0002] Conventionally, image reading devices mounted on copying machines, facsimile machines, digital multifunction machines, etc. are known that read images on a document while conveying the document by an ADF (Auto Document Feeder). A sheet conveying device used in such image reading devices separates and feeds sheets loaded on a loading tray one by one, and discharges the sheets to a discharge tray.

[0003] As a configuration of the stacking tray, a stacking tray having a stacking surface that can be moved in the width direction and retreated has been proposed (Patent Document 1). This configuration improves the visibility and ease of removal of sheets discharged onto the discharge tray.

[0004] Furthermore, when a sheet becomes charged during transport, this can cause improper stacking of the sheet on the discharge tray. In order to prevent such improper stacking, a sheet transport device has been proposed in which a charge eliminating member is provided on the surface of the stack tray opposite the stacking surface (Patent Document 2). When a sheet is discharged, the sheet comes into contact with the charge eliminating member arranged on the bottom surface of the stack tray, thereby reducing improper stacking caused by charge on the sheet. Furthermore, such charge eliminating members are arranged across the entire width in order to eliminate charge on sheets of various sizes. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-210611 A [Patent Document 2] JP 2018-172190 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in a stacking tray having a stacking surface that can be moved in the width direction and retracted, the width of the stacking tray itself changes (expands and contracts) depending on the size of the document, so it was difficult to provide a static eliminator on the bottom surface of the stacking tray as in the past. Therefore, there was a risk that discharged sheets would not be neutralized and stacking failure would occur.

[0007] SUMMARY OF THE PRESENT DISCLOSURE In view of the above, an object of the present invention is to prevent the occurrence of improper stacking of discharged sheets in a sheet transport device having a stacking tray that is extendable in the width direction. [Means for solving the problem]

[0008] In order to solve the above problems, one aspect of the present invention is a sheet conveying device comprising: a loading tray having a first support portion that supports a sheet; a second support portion that is arranged to be movable in the sheet width direction relative to the first support portion between a first position that supports a sheet together with the first support portion and a second position retracted from the first position; a feeding means that feeds sheets loaded on the loading tray; a discharge means that discharges the sheets fed by the feeding means; and a discharge tray that is arranged below the loading tray and on which the sheets discharged by the discharge means are loaded, wherein the loading tray has a first charge neutralizing member that is arranged on a first bottom surface opposite to a first support surface that supports the sheets in the first support portion and discharges the sheets discharged by the discharge means; and a second charge neutralizing member that is arranged on a second bottom surface opposite to a second support surface that supports the sheets in the second support portion and discharges the sheets discharged by the discharge means, wherein the second charge neutralizing member is drawn out from the first support portion as the second support portion moves from the second position to the first position. Effect of the Invention

[0009] According to the present invention, in a sheet transport device having a stacking tray that is extendable in the width direction, it is possible to prevent the occurrence of stacking errors of discharged sheets. [Brief description of the drawings]

[0010] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] 1A is a cross-sectional view of the first support member and the second support member, and FIG. [Diagram 5] 1A is a cross-sectional view of the document tray when the second support member is pulled out, and FIG. [Figure 6] FIG. 4 is a perspective view of the document tray with a small-sized document placed thereon. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] 1A is a perspective view of the upper surface of a first cover member, and FIG. [Figure 11] 1A is a rear view of the image reading device, and FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Note that the following embodiment is an example of the present invention, and is not intended to limit the technical scope of the present invention.

[0012] [Image forming device] First, an image forming apparatus according to the present embodiment will be described. Fig. 1 is a schematic cross-sectional view of a printer 100 as an image forming apparatus according to the present embodiment. The printer 100 is an electrophotographic laser beam printer. The printer 100 includes a printer body 100a and an image reading device 1 attached to the upper part of the printer body 100a.

[0013] Hereinafter, the side of printer 100 where an operation unit (not shown) is provided will be referred to as the front side, and the opposite side will be referred to as the rear side. That is, Fig. 1 is a diagram of printer 100 as seen from the front side. In addition, in this embodiment, the sheet includes, in addition to plain paper, special paper such as coated paper, recording materials having special shapes such as envelopes and index paper, plastic films and cloths for overhead projectors, and the original document is also an example of a sheet.

[0014] The printer main body 100a has an image forming engine 110. The image forming engine 110 includes an image forming unit PU as an electrophotographic image forming means, and a fixing device 107. When a command is issued to start an image forming operation, a photosensitive drum 101, which is a photoconductor, rotates, and the drum surface is uniformly charged by a charging device 102. Then, an exposure device 103 modulates and outputs a laser beam based on image data transmitted from the image reading device 1 or an external computer, and scans the surface of the photosensitive drum 101 to form an electrostatic latent image. This electrostatic latent image is visualized (developed) by toner supplied from a developing device 104 to become a toner image.

[0015] In parallel with such image forming operation, a feeding operation is performed to feed the recording material S loaded on a cassette 109 or a manual feed tray (not shown) toward the image forming engine 110. The fed recording material S is transported in accordance with the progress of the image forming operation by the image forming unit PU. Then, the toner image carried on the photosensitive drum 101 is transferred to the recording material S by the transfer roller 105. Toner remaining on the photosensitive drum 101 after the toner image transfer is collected by a cleaning device 106. The recording material S with the transferred unfixed toner image is delivered to a fixing device 107, where it is sandwiched between a pair of rollers and heated and pressurized. The recording material S with the fixed toner is discharged to a discharge tray 111.

[0016] [Image reader] Next, the image reading device 1 will be described. FIG. 2 is a perspective view of the image reading device 1. The image reading device 1 is composed of an ADF 2 and an image reading section 3. The ADF is an automatic document feeder. As shown in FIG. 1, the image reading section 3 has a first reading unit 31 that reads an image from a document D, a document table glass 32 that is a transparent member, and a flow reading glass 33 that is a transparent member. The ADF 2 is provided so as to be openable and closable with respect to the image reading section 3 by a hinge (not shown). With the ADF 2 open with respect to the image reading section 3, the user can place a document on the document table glass 32. The first reading unit 31 is provided so as to be movable in the sub-scanning direction (left and right direction in the figure) along the document table glass 32 by a motor and a drive belt (not shown). The first reading unit 31 can read the image of the document placed on the document table glass 32 while moving in the sub-scanning direction (fixed reading). Furthermore, while waiting at the first reading position P1, the first reading unit 31 is capable of reading an image on the first side (front side) of the document D conveyed by the ADF 2 through the flow reading glass 33 (flow reading).

[0017] The ADF2 has a second reading unit 21 that reads an image from a second side (reverse side) of the document D. The second reading unit 21 reads an image from the second side of the document D transported by the ADF2 at a second reading position P2 downstream of the first reading position P1 in the transport direction of the document D.

[0018] The ADF 2 includes a document tray 4 as a loading tray on which documents D are loaded, a transport section 22 that transports the documents D loaded on the document tray 4, and a discharge tray 5 on which documents D discharged from the ADF 2 are loaded. The transport section 22 includes a feed roller 23 as a feeding means for feeding the documents D loaded on the document tray 4, and a separation roller pair 24 as a separation means for separating the documents D fed by the feed roller 23 one by one. The transport section 22 further includes a first transport roller pair 25 that pulls out the documents D from the nip portion of the separation roller pair 24, and a plurality of transport roller pairs that sequentially transfer and transport the documents D received from the first transport roller pair 25. The transport section 22 includes a discharge roller pair 26 as a discharge means for discharging the documents D to the discharge tray 5.

[0019] The discharge tray 5 is disposed below the document tray 4 in the vertical direction. The transport path 27 inside the transport section 22 is curved in a U-shape as shown in Fig. 1. The document D fed from the document tray 4 has its image read by the first reading unit 31 and the second reading unit 21 while being transported along the curved transport path 27 by the above-mentioned multiple transport roller pairs. Then, the document D whose image has been read is discharged from the outlet of the transport path 27 to the discharge tray 5 by the discharge roller pair 26.

[0020] [Document tray configuration] Next, the configuration of the document tray 4 will be described with reference to Figs. 3 to 6. Fig. 3 is a perspective view of the document tray 4. Fig. 4(a) is a cross-sectional view of the AA section in Fig. 3 viewed in the Y direction, and Fig. 4(b) is a plan view of Fig. 4(a) viewed in the Z direction. Note that a first cover member 45 and a second cover member 46 described later are not shown in Fig. 4. Fig. 5 is a cross-sectional view showing the document tray 4 during width expansion and contraction. Fig. 6 is a perspective view of the document tray 4 in a state in which a small-sized document is placed. The X direction in Fig. 3 is the sheet width direction (also simply referred to as the width direction), the Y direction is the sheet feed direction (also simply referred to as the feed direction), and the Z direction is the vertical direction. Note that the sheet width direction is perpendicular to the sheet feed direction.

[0021] As shown in FIG. 3, the document tray 4 is composed of a first support member 41, a second support member 42, a first side regulating plate 43, a second side regulating plate 44, a first cover member 45, and a second cover member 46. The first support member 41 and the second support member 42 support the document D loaded by the user. The first side regulating plate 43 and the second side regulating plate 44 are each movable in the width direction and are moved according to the width of the document D to regulate the position of the document D in the width direction. At this time, the first side regulating plate 43 abuts against the front end of the document D, and the second side regulating plate 44 abuts against the front end of the document D. In this embodiment, the second side regulating plate 44 is an example of the first regulating member, and the first side regulating plate 43 is an example of the second regulating member. The first cover member 45 covers the first support member 41 from below, and the second cover member 46 covers the second support member 42 from below. The first supporting member 41 and the first cover member 45 constitute a first supporting portion in this embodiment, and the second supporting member 42 and the second cover member 46 constitute a second supporting portion in this embodiment.

[0022] As shown in FIGS. 4(a) and 4(b), the first side regulating plate 43 is provided with a first guide rack 431, and the second side regulating plate 44 is provided with a second guide rack 441. The first guide rack 431 and the second guide rack 441, together with a pinion gear 411 attached to the first support member 41, constitute a pinion rack mechanism (interlocking mechanism). Specifically, the first guide rack 431 and the second guide rack 441 each have a plurality of teeth arranged in a straight line. The teeth formed on the first guide rack 431 and the second guide rack 441 are arranged so as to mesh with the pinion gear 411. This allows the first side regulating plate 43 and the second side regulating plate 44 to move in the width direction in an interlocking manner with each other.

[0023] The second support member 42 is movable in the width direction relative to the first support member 41 between a drawn-out position (position shown in FIG. 3 and FIG. 5(a)) where the second support member 42 supports the sheet together with the first support member 41, and a retracted position (position shown in FIG. 5(b) and FIG. 6) retracted from the drawn-out position. In the drawn-out position, which is the first position, the support surface 42a of the second support member 42 is exposed when viewed from above, and the second support member 42 can support the sheet together with the support surface 41a of the first support member 41. On the other hand, in the retracted position, which is the second position, the second support member 42 is located below the first support member 41, and the support surface 42a of the second support member 42 is covered by the support surface 41a of the first support member 41 when viewed from above. The support surface 41a of the first support member 41 is the first support surface in this embodiment, and the support surface 42a of the second support member 42 is the second support surface in this embodiment.

[0024] In addition, since the first side regulating plate 43 and the second cover member 46 are fixed to the second support member 42, they move in the width direction together with the second support member 42. That is, the user can move the second support member 42 by grasping the first side regulating plate 43 and moving it in the width direction. However, as described above, since the first side regulating plate 43 and the second side regulating plate 44 move in conjunction with each other, the conveying center is always constant. When the second support member 42 is located at the pull-out position, the second cover member 46 is also exposed when viewed from below. On the other hand, when the second support member 42 is located at the retracted position, the second cover member 46 is covered from below by the first cover member 45. That is, the second support member 42 and the second cover member 46 are stored between the first support member 41 and the first cover member 45, and are pulled out from between the first support member 41 and the first cover member 45. In other words, the second support part is configured so as to be able to be stored in the inside of the first support part and to be able to be pulled out from the inside of the first support part.

[0025] Therefore, when a large-sized original D is set, as shown in Fig. 3, both the support surface 41a of the first support member 41 and the support surface 42a of the second support member 42 support the original D, so that the original tray 4 can support the large-sized original D over a wide area. On the other hand, when a small-sized original D is set, as shown in Fig. 6, the second support member 42 retreats to the retreat position and the width of the original tray 4 is partially reduced. In other words, the original tray 4 can expand and contract according to the size of the set original D. This improves the visibility of the original D discharged to the discharge tray 5 arranged below the original tray 4, making it easier to take out.

[0026] [Static charge removal configuration for ejected documents] In the image reading device 1, while the original D is being transported by the ADF 2, the original D may become charged due to friction with the transport guide surface, rollers, etc. This causes a problem of poor loading when the original D is loaded onto the discharge tray 5. Conventionally, there is a configuration in which a charge removing member is provided across the entire width of the bottom surface of the original tray to remove charge from the sheet. However, since the original tray 4 in this embodiment is configured such that its width expands and contracts according to the size of the original, it is difficult to adopt a configuration in which a charge removing member is provided as in the conventional configuration.

[0027] Therefore, in this embodiment, the neutralization member is divided into two and arranged on the document tray 4 so that the width of the neutralization member also expands and contracts with the expansion and contraction of the document tray 4. Specifically, as shown in FIG. 5, a first neutralization member 47 is provided on the bottom surface 45a of the first cover member 45, and a second neutralization member 48 is provided on the bottom surface 46a of the second cover member 46. Since neutralization members are arranged on each of the first cover member 45 and the second cover member 46 in this manner, the length of the neutralization member as a whole also expands and contracts with the expansion and contraction of the document tray 4. This makes it possible to exert a neutralization effect on documents of various sizes. The bottom surface 45a is the first bottom surface opposite the support surface 41a of the first support portion, and the bottom surface 46a is the second bottom surface opposite the support surface 42a of the second support portion.

[0028] The detailed configurations of the first charge eliminating member 47 and the second charge eliminating member 48 will be described below. Fig. 7 is a perspective view of the bottom surface of the document tray 4. Fig. 8 is a perspective view of the bottom surface 45a of the first cover member 45. Fig. 9 is a perspective view of the bottom surface 46a of the second cover member 46. Fig. 10 is a perspective view of the top surface of the first cover member 45 and an enlarged view thereof. Fig. 11 is a rear view of the image reading device 1 and an enlarged view thereof.

[0029] 8, a first charge eliminating member 47 is provided on the bottom surface 45a of the first cover member 45. The first charge eliminating member 47 is made up of a conductive tape portion 471 having an adhesive layer on one side, and a conductive brush portion 472. The first charge eliminating member 47 is attached to the first cover member 45 by the adhesive layer of the tape portion 471, and has an extension portion 473 that extends to the side surface of the first cover member 45. The first charge eliminating member 47 can eliminate charge on the document D by contacting the document D with the brush portion 472, which is provided over substantially the entire area in the width direction of the bottom surface 45a of the first cover member 45.

[0030] As shown in FIG. 9, a second charge removing member 48 is provided on the bottom surface 46a of the second cover member 46. The second charge removing member 48 is composed of a conductive tape portion 481 having an adhesive layer on one side, and a conductive brush portion 482. The second charge removing member 48 is attached to the second cover member 46 by the adhesive layer of the tape portion 481. The second charge removing member 48 can remove charge from the document D by contacting the brush portion 482, which is provided over substantially the entire area in the width direction of the bottom surface 46a of the second cover member 46, with the document D. In addition, the second charge removing member 48 is disposed at the same position as the first charge removing member 47 in the discharge direction of the discharge roller pair 26. Since the second charge removing member is attached to the second cover member 46, it moves in the width direction with the movement of the second support member 42. That is, as the second support member 42 moves from the retracted position to the pulled-out position, the second charge eliminating member 48 is pulled out from between the first support member 41 and the first cover member 45. Therefore, the total length of the exposed portions of the first charge eliminating member 47 and the second charge eliminating member 48 that can come into contact with the document changes depending on the size of the document placed on the document tray 4.

[0031] FIG. 10(a) is a view of the first cover member 45 viewed from above, and FIG. 10(b) is an enlarged view of the dotted line portion of FIG. 10(a). As shown in FIG. 10, the connection member 8 is attached to the first cover member 45 from above the first charge removing member 47. The connection member 8 is formed of an elastic member having electrical conductivity. The connection member 8 has a protrusion 81 protruding upward, a hole 82, and a claw portion 83. As shown in FIG. 5, when the first cover member 45 and the second cover member 46 are combined, the tip of the protrusion 81 of the connection member 8 comes into contact with the second charge removing member 48, so that the first charge removing member 47 and the second charge removing member 48 can be electrically connected. When the second support member 42 moves between the drawn-out position and the retracted position, the protrusion 81 of the connection member 8 slides against the second charge removing member 48. As a result, the first charge eliminating member 47 and the second charge eliminating member 48 are always electrically connected to each other regardless of the position of the second support member 42.

[0032] A boss 451 provided on the first cover member 45 fits into a hole 82 of the connection member 8, and a claw portion 83 of the connection member 8 is inserted into a hole 452 provided in the first cover member 45, whereby the connection member 8 is fixed to the first cover member 45. Note that a part of the tip of the boss 451 of the first cover member 45 is thicker than the hole 82 of the connection member 8 to prevent it from coming off.

[0033] Next, a method of connecting (grounding) each charge removing member to the earth will be described. FIG. 11(a) is a view of the image reading device 1 as seen from the back, and FIG. 11(b) is an enlarged view of the dotted line portion of FIG. 11(a). In FIG. 11, the rear cover 11 (see FIG. 2) is omitted for the sake of explanation. As shown in FIG. 11, the conductive wire member 71 is arranged in a manner sandwiched between the main body frame 6 and the metal plate 7, which are made of metal, and extends to a position where it contacts the extension portion 473 of the first charge removing member 47. That is, the extension portion 473 of the first charge removing member 47 is electrically connected to the main body frame 6 via the wire member 71. Therefore, by connecting the main body frame 6 to the earth, the first charge removing member 47 is also connected to the earth. Also, as shown in FIG. 5, the first charge removing member 47 and the second charge removing member 48 are always electrically connected to each other via the connection member 8. Since the first charge removing member 47 is connected to the ground as described above, the second charge removing member 48 is connected to the ground via the first charge removing member 47 .

[0034] As described above, in this embodiment, the first charge eliminating member 47 is disposed on the bottom surface 45a of the first cover member 45, and the second charge eliminating member 48 is disposed on the bottom surface 46a of the second cover member 46. The second charge eliminating member 48 is configured to be drawn out from between the first support member 41 and the first cover member 45 as the second support member 42 moves from the retracted position to the drawn-out position. This makes it possible to appropriately eliminate charge on the document being discharged even in a configuration in which the width of the document tray 4 expands and contracts.

[0035] Furthermore, the second charge removing member 48 is always electrically connected to the first charge removing member 47 regardless of the position of the second support member 42, and is connected to the earth via the first charge removing member 47. This makes it possible to reduce the number of parts and achieve cost reductions compared to a configuration in which the first charge removing member 47 and the second charge removing member 48 are separately connected to the earth.

[0036] In this embodiment, a configuration has been described in which a charge eliminating needle having a brush portion is used as the first charge eliminating means and the second charge eliminating means. However, the effects of the present invention can be obtained regardless of the charge eliminating means. Also, in this embodiment, a configuration has been described in which the first charge eliminating member 47 and the second charge eliminating member 48 are arranged on the same straight line in the discharge direction. However, even if the first charge eliminating member 47 and the second charge eliminating member 48 are arranged at positions offset from each other in the discharge direction, the effects of the present invention can be obtained in the same manner as above as long as the charge eliminating means are electrically connected. [Explanation of symbols]

[0037] 1 Image reader 2 ADF 3 Image reading unit 4 Document Tray 41 First support member 42 Second support member 47 First static elimination member 48 Second static elimination member

Claims

1. a stacking tray including a first support portion that supports a sheet, and a second support portion that is movable in a sheet width direction relative to the first support portion between a first position that supports the sheet together with the first support portion and a second position that is retracted from the first position; a feeding means for feeding the sheets stacked on the stacking tray; a discharge means for discharging the sheet fed by the feeding means; a discharge tray provided below the stacking tray and configured to receive the sheets discharged by the discharge unit; Equipped with The loading tray is a first charge removing member that is disposed on a first bottom surface of the first support portion opposite to a first support surface that supports the sheet, and that removes charge from the sheet discharged by the discharge means; a second charge removing member that is disposed on a second bottom surface of the second support portion opposite to a second support surface that supports the sheet, and that removes charge from the sheet discharged by the discharge means; having the second charge removing member is pulled out from the first support portion as the second support portion moves from the second position to the first position. A sheet conveying device comprising:

2. The second charge removing member is connected to a ground via the first charge removing member.

2. The sheet transport device according to claim 1.

3. the loading tray has a connection member that slides against the second charge removing member when the second support portion moves and electrically connects the first charge removing member and the second charge removing member.

3. The sheet transport device according to claim 2.

4. the connecting member is an elastic member fixed to the first support portion and has a protrusion that protrudes upward and slides against the second static eliminating member; 4. The sheet transport device according to claim 3.

5. The first charge removing member and the second charge removing member are disposed at the same position in a discharge direction of the discharge means.

2. The sheet transport device according to claim 1.

6. The first charge removing member is provided across the entire area of ​​the first bottom surface in the sheet width direction, The second charge removing member is provided across the entire area of ​​the second bottom surface in the sheet width direction.

2. The sheet transport device according to claim 1.

7. the first support portion includes a first support member including the first support surface, and a first cover member including the first bottom surface and covering the first support member from below, the second support portion includes a second support member including the second support surface, and a second cover member including the second bottom surface and covering the second support member from below, The second support portion is housed between the first support member and the first cover member when moving from the first position to the second position.

2. The sheet transport device according to claim 1.

8. The stacking tray has a first regulating member disposed at the first support portion and regulating a position of the sheet in the sheet width direction, a second regulating member disposed at the second support portion and regulating a position of the sheet in the sheet width direction, and an interlocking mechanism that moves the first regulating member and the second regulating member in an interlocking manner.

2. The sheet transport device according to claim 1.

9. A sheet conveying device according to any one of claims 1 to 8, a reading means for reading an image on the sheet fed by the feeding means, 1. An image reading apparatus comprising:

10. The image reading device according to claim 9 ; and an image forming unit that forms an image on a recording material based on the image on the sheet read by the reading unit.

1. An image forming apparatus comprising:

Images