Sheet feeding device, image reading device, and image forming device

Abstract

To reduce occurrence of conveying failure and skew of a sheet having small size in a width direction.SOLUTION: An ADF comprises a document tray, a pickup roller for feeding a document, and a first side regulation plate 31 and a second side regulation plate 32 arranged on a top surface of the document tray so as to be moved in a width direction of the document. The first side regulation plate 31 includes a first regulation surface 31Aa for regulating a position of the document in the width direction, and a first bottom plate part 31B slid with respect to the top surface of the document tray. The second side regulation plate 32 includes a second regulation surface 32Aa for regulating the position of the document in the width direction, and a second bottom plate part 32B slid with respect to the top surface of the document tray. A part of the first bottom plate part 31B is positioned on the side of the second regulation surface 32Aa beyond a middle position B in a state where the first regulation surface 31Aa and the second regulation surface 32Aa are brought closest to each other in the width direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a sheet feeding device, an image reading device, and an image forming apparatus, which are provided with a first regulating portion and a second regulating portion that regulate a position of a sheet in a width direction on a stacking tray for stacking sheets. [Background technology]

[0002] For example, some image forming apparatuses such as copiers and multifunction machines are equipped with an automatic document feeder (hereinafter referred to as "ADF") that transports a document, which is a sheet, to an image reading unit. In general, in such an ADF, a document tray on which documents (sheets) are loaded is equipped with two side regulating plates (side guide mechanisms) that abut on both sides of the widthwise ends of the document to regulate the widthwise position of the document (see Patent Document 1). A user places a document on the document tray and slides the two side regulating plates so that they abut on the widthwise ends of the document. This regulates the widthwise position of the document set on the loading tray, and the document can be well oriented when it is subsequently fed and the image is read by the image reading device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-8766 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the above-mentioned side regulating plate has a regulating portion having a regulating surface that abuts against the widthwise end of the document, and a bottom plate portion that is slidably provided on the upper surface of the stacking tray and is integral with the regulating portion. If the bottom plate portion is provided on the outer side opposite to the side that regulates the document with respect to the regulating portion, it becomes necessary to increase the width of the ADF in order to be able to move the side regulating plate to the outermost side in the width direction when setting a document with a large width. Therefore, the bottom plate portion is provided on the side of the regulating surface of the regulating portion, that is, on the inner side in the width direction of the two side regulating plates.

[0005] On the other hand, in recent years, there has been a demand for documents with small widths, such as business cards, to be fed and read using the ADF. In order to configure the scanner to be able to load documents with small widths, such as business cards, it is necessary to bring the regulating parts of the two side regulating plates closer together in the width direction, and this can be achieved by shortening the width of the bottom plate.

[0006] However, if there is a component tolerance in the height direction between the part below the regulating part that slides against the loading tray and the part below the tip of the bottom plate that slides against the loading tray, the regulating surface will be inclined. If the length of the bottom plate in the width direction is shortened, the parts where the height difference occurs due to the component tolerance will be closer, so there is a problem that the effect of the component tolerance will be greater, that is, the inclination of the regulating surface will be greater. If the regulating surface is inclined toward the inside of the two side regulating plates, when a stack of documents is set, the documents will be clamped in the width direction, especially above the regulating surface, and the transport resistance will be greater, making it easier to cause transport failures. On the other hand, if the regulating surface is inclined toward the outside of the two side regulating plates, a gap will be generated between the width direction end of the documents and the regulating surface, especially above the regulating surface, and the documents will be inclined with respect to the feeding direction, making it easier to cause skew during feeding.

[0007] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a sheet feeding device, an image reading device, and an image forming apparatus that are capable of reducing the occurrence of poor transport and skew of sheets that are small in width. [Means for solving the problem]

[0008] One aspect of the present invention is a sheet feeding device that includes a loading tray having a loading surface for loading sheets, a feeding section that feeds the sheets loaded on the loading tray, and a first regulating section and a second regulating section that are movable in a width direction perpendicular to a sheet feeding direction and that regulate a position in the width direction of the sheets loaded on the loading surface, the loading surface having a first slit extending in the width direction and a second slit that is disposed at a position different from the first slit in the feeding direction and extends in the width direction, and the first regulating section the first regulating surface abuts against one end in the width direction of the sheets loaded on the loading surface, a first bottom plate portion that slides against an upper surface of the loading tray and supports the sheets together with the loading surface, and a first protrusion portion that moves inside the first slit; the second regulating surface abuts against the other end in the width direction of the sheets loaded on the loading surface, and a second bottom plate portion that slides against the upper surface of the loading tray and supports the sheets together with the loading surface; and a second protrusion that moves inside the second slit, wherein the first bottom plate portion has a first inclined portion inclined with respect to the feeding direction such that an outer edge of the first regulating surface side in the width direction moves away from the first regulating surface as it moves downstream in the feeding direction when viewed from above, and the second bottom plate portion has a second inclined portion inclined with respect to the feeding direction such that an outer edge of the first regulating surface side in the width direction moves closer to the second regulating surface as it moves downstream in the feeding direction when viewed from above, a first tip portion that is located closest to the second regulating surface in the width direction in the first regulating portion and a second tip portion that is located closest to the first regulating surface in the width direction in the second regulating portion are positioned at different positions from each other in the feeding direction, and when the first regulating surface and the second regulating surface move from their farthest positions to their closest positions, the first tip portion and the second tip portion pass a center position between the first regulating surface and the second regulating surface.

[0009] Also, one aspect of the present invention includes a loading tray having a loading surface on which sheets are loaded, a feeding section that feeds the sheets loaded on the loading tray, and a first regulating section and a second regulating section that are movable in a width direction perpendicular to a sheet feeding direction and regulate a position in the width direction of the sheets loaded on the loading surface, the loading surface having a first slit extending in the width direction and a second slit that is provided at a position different from the first slit in the feeding direction and extends in the width direction, the first regulating section has a first regulating surface that abuts against one end in the width direction of the sheets loaded on the loading surface, a first bottom plate section that slides against an upper surface of the loading tray and supports the sheets together with the loading surface, and a first protruding section that moves inside the first slit, the second regulating section has a second regulating surface that abuts against the other end in the width direction of the sheets loaded on the loading surface, and a second regulating section that abuts against the other end in the width direction of the sheets loaded on the loading surface. the first bottom plate portion has a first inclined portion inclined with respect to the feeding direction so that an outer edge of the first regulating surface side in the width direction moves away from the first regulating surface as it moves downstream in the feeding direction when viewed from above, and the second bottom plate portion has a second inclined portion inclined with respect to the feeding direction so that an outer edge of the first regulating surface side in the width direction moves closer to the second regulating surface as it moves downstream in the feeding direction when viewed from above, and the first regulating portion and the second regulating portion do not overlap when viewed from the feeding direction at a position where the first regulating surface and the second regulating surface are furthest from each other, and at least partially overlap when viewed from the feeding direction at a position where the first regulating surface and the second regulating surface are closest to each other. Effect of the Invention

[0010] According to the present invention, it is possible to reduce the occurrence of poor conveyance and skew of a sheet having a small size in the width direction. [Brief description of the drawings]

[0011] [Figure 1]1 is an overall perspective view showing a printer according to a first embodiment. [Diagram 2] 1A is a schematic cross-sectional view showing an image reading device including an ADF according to a first embodiment, and FIG. [Diagram 3] 1A is a general perspective view showing the ADF according to the first embodiment with the first and second side restriction plates closed, and FIG. 1B is a general perspective view showing the ADF according to the first embodiment with the first and second side restriction plates opened. [Figure 4] 1A is a perspective view showing only the first and second side regulating plates according to the first embodiment, and FIG. 1B is an enlarged perspective view showing the first and second side regulating plates according to the first embodiment provided on a stacking tray. [Diagram 5] 1A is an enlarged perspective view showing a state in which a first side regulating plate and a second side regulating plate are provided on a stacking tray according to the first embodiment, and FIG. [Figure 6] 1A is a perspective view showing the side regulating mechanism in a state in which the first and second side regulating plates are open, and FIG. [Figure 7] 1A is a schematic cross-sectional view showing the relationship between the component tolerance of the second side regulating plate, the inclination of the regulating surface, and the positional tolerance of the regulating surface in the first embodiment, and FIG. [Figure 8] 1A is a general perspective view showing an ADF according to a second embodiment with a first side regulating plate and a second side regulating plate in a closed state, and FIG. [Figure 9] 10A is a general perspective view showing an ADF according to a third embodiment with a first side regulating plate and a second side regulating plate in a closed state, and FIG. [Figure 10]13A is a general perspective view showing an ADF in a state where a first side regulating plate and a second side regulating plate are closed according to a fourth embodiment, and FIG. 13B is a perspective view showing only the first side regulating plate and the second side regulating plate according to the fourth embodiment. [Figure 11] 1A is a general perspective view showing an ADF in a state where the first and second side regulating plates, which have a short first and second bottom plate portions, are closed, and FIG. 1B is a general perspective view showing an ADF in a state where the first and second side regulating plates, which have a short first and second bottom plate portions, are opened. [Figure 12] 1A is a schematic cross-sectional view showing the relationship between the component tolerance, the inclination of the regulating surface, and the positional tolerance of the regulating surface in the second side regulating plate when the second bottom plate portion is shortened, and FIG. 1B is a schematic top view showing the relationship between the positional tolerance of the first and second regulating surfaces and the document to be set when the first and second bottom plate portions are shortened. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] <First embodiment> [Overall configuration] A first embodiment will be described below. A printer 100 as an image forming apparatus according to the first embodiment is an electrophotographic laser beam printer. As shown in FIG. 1, the printer 100 includes a printer body 70, an image reading device 10 attached to the top of the printer body 70, and an operation unit 90 having a display unit 91 and operation keys 92 capable of various notifications and operations. As shown in FIG. 2(b), the printer body 70 includes an image forming engine 60. In the following description, the term "sheet" includes not only plain paper, but also special paper such as cardboard and coated paper, recording materials of special shapes such as envelopes and index paper, and plastic films and cloths for overhead projectors, and a manuscript is also an example of a sheet.

[0013] As shown in Fig. 2(b), the image forming engine 60 as an image forming section includes an image forming unit PU as an electrophotographic image forming means, and a fixing device 7. When a command is issued to start an image forming operation, the photosensitive drum 1, which is a photoconductor, rotates, and the drum surface is uniformly charged by the charging device 2. Then, the exposure device 3 modulates and outputs a laser beam based on image data transmitted from the image reading device 10 or an external computer, and scans the surface of the photosensitive drum 1 to form an electrostatic latent image. This electrostatic latent image is visualized (developed) by toner supplied from the developing device 4 to become a toner image.

[0014] In parallel with such image forming operation, a feeding operation is performed to feed a sheet loaded on a cassette or manual feed tray (not shown) toward the image forming engine 60. The fed sheet 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 1 is transferred to the sheet by the transfer roller 5. Toner remaining on the photosensitive drum 1 after the toner image transfer is collected by a cleaning device 6. The sheet onto which the unfixed toner image has been transferred is delivered to a fixing device 7, where it is sandwiched between a pair of rollers and heated and pressed. The sheet onto which the toner has been fused and fixed to the sheet and the image has been fixed is discharged by a discharge means such as a pair of discharge rollers.

[0015] [Image reader] Next, the image reading device 10 will be described in detail. As shown in FIG. 2(a), the image reading device 10 includes an ADF (automatic document feeder) 20 that feeds documents loaded on a document tray 121 as a loading tray and discharges them to a discharge tray 122, and a reading unit 40 that reads the documents transported by the ADF 20. That is, the ADF 20 constitutes a sheet feeding device that transports sheets as documents to the reading unit 40. The reading unit 40 has a front surface reading unit 104 as a reading section that reads an image on the front surface of the document. The ADF 20 is supported rotatably with respect to the reading unit 40 by a hinge (not shown) so that the document table glass 101 can be opened. The document, which is an example of a sheet, may be blank paper or may have an image formed on one or both sides.

[0016] The ADF 20 has a pickup roller 111 as a feeding section, and a separation drive roller 112 and a retard roller 113 that constitute a separation roller pair. The ADF 20 also has a registration roller pair 114, a lead roller pair 115, a transport roller pair 117, and a discharge roller pair 119. The ADF 20 also has a back side reading unit 105 as a reading section. Meanwhile, the reading unit 40 has a platen glass 102, a document table glass 101, and a front side reading unit 104 as an image reading means. The front side reading unit 104 is configured to be slidable, that is, configured to be movable in the sub-scanning direction of a reading sensor (not shown).

[0017] As shown in Fig. 3(a) and Fig. 3(b), the document tray 121 is provided with a side regulating mechanism 30 as a width regulating means that is movable in a width direction perpendicular to the feeding direction on the document loading surface and abuts against the end of the document in the width direction to regulate the position of the document in the width direction. The side regulating mechanism 30 is composed of a pair (two) of a first regulating portion and a second regulating portion, a first side regulating plate 31 and a second side regulating plate 32, which are movable in the width direction. The first side regulating plate 31 and the second side regulating plate 32 are connected to an interlocking mechanism 50 composed of a rack and pinion mechanism described later in detail (see Fig. 6(a) and Fig. 6(b)). As a result, when one of the first side regulating plate 31 and the second side regulating plate 32 moves, the other moves in the width direction in conjunction with the first side regulating plate 31 and the second side regulating plate 32. That is, the center of transport of the document is located at the center in the width direction, and these side regulating plates 31, 32 are configured to approach or move away from the center in the width direction, that is, configured so that the center of the document is at the same position as the transport center regardless of the size of the document.

[0018] Next, the operation of reading an original will be described with reference to Fig. 2(a). The image reading device 10 reads image information from an original in a flow reading mode in which an original image is scanned while the original loaded on the original tray 121 is transported by the ADF 20, and in a fixed reading mode in which an original placed on the original platen glass 101 is scanned. The flow reading mode is selected when an original presence / absence sensor (not shown) detects an original loaded on the original tray 121, or when a user explicitly instructs the mode via the operation unit 90 or the like.

[0019] When the flow reading mode is executed, the pickup roller 111 descends and contacts the topmost document on the document tray 121. The document is then transported by the pickup roller 111 and separated one by one at a separation nip formed by the separation drive roller 112 and the retard roller 113. A torque limiter is disposed in the rotation support structure of the retard roller 113, and the retard roller 113 rotates together with the separation drive roller 112 when the number of transported documents is one, and does not rotate when the number of transported documents is two or more. This allows the documents to be separated one by one. Note that a drive in the opposite direction to the sheet transport direction may be input to the retard roller 113. Meanwhile, in order to read the document transported at the same time as the pickup roller 111 descends, the front surface reading unit 104 is moved below the platen glass 102. The transported document is transported toward the platen glass 102 by the registration roller pair 114 and the lead roller pair 115.

[0020] In the case of front side reading, the image on the front side of the document is read by the front side reading unit 104 through the platen glass 102. The reading surface is illuminated by the light source of the front side reading unit 104, and the reflected light from the document surface is photoelectrically converted line by line by the light receiving element of the reading sensor (not shown). The photoelectrically converted image information is transferred to an image memory of the control unit (not shown). Then, the document that has passed through the platen glass 102 is guided to a pair of transport rollers 117 and discharged to a discharge tray 122 by a pair of discharge rollers 119.

[0021] In the case of double-sided reading, as described above, the front side is read by the front side reading unit 104, and the image on the back side of the document is read by the back side reading unit 105. Similarly, the reading surface is illuminated by the light source of the back side reading unit 105, and the reflected light from the document surface is photoelectrically converted line by line by the light receiving element of the reading sensor (not shown). The photoelectrically converted image information is transferred to the image memory of the control unit.

[0022] On the other hand, the fixed reading mode is selected when the device detects an original placed on the glass platen 101 or when the user explicitly instructs this via the operation unit 90. In this case, the original on the glass platen 101 does not move, and the front surface reading unit 104 is moved along the glass platen 101 to scan the original. Similarly, image information photoelectrically converted by the light receiving element of the reading sensor of the front surface reading unit 104 is transferred to the image memory of the control unit.

[0023] [Details of the side regulation mechanism] Next, the detailed configuration of the side regulating mechanism 30 will be described with reference to Figs. 4(a), 4(b), 5(a), 5(b), 6(a), and 6(b). As shown in Figs. 4(a) and 6(a), the side regulating mechanism 30 is roughly configured to include a first side regulating plate 31, a second side regulating plate 32, and an interlocking mechanism 50 for interlocking their widthwise movements. In the following description, the side facing the center position B between the first side regulating plate 31 and the second side regulating plate 32 is referred to as the inside, and the opposite side is referred to as the outside. In addition, in describing the first bottom plate portion 31B and the second bottom plate portion 32B described later, the parts that are integrally connected to the first regulating portion 31A and the second regulating portion 32A in the width direction of the sheet are referred to as the root, and the opposite side is referred to as the tip, and are referred to as the root side and the tip side, respectively.

[0024] In the first embodiment, the first side regulating plate 31 has a first regulating portion 31A, a first bottom plate portion 31B, and a first slider portion 31C, as shown in Fig. 4(a) and Fig. 6(a). The first regulating portion 31A is disposed so as to protrude upward from the document stacking surface 121a of the document tray 121, as shown in Fig. 4(a) and Fig. 4(b). The first regulating portion 31A is formed with a first regulating surface 31Aa that abuts against an end of the document in the width direction loaded on the document tray 121 to regulate the position of the document. The first regulating surface 31Aa is disposed facing inward between the first side regulating plate 31 and the second side regulating plate 32 so as to face a second regulating surface 32Aa of the second side regulating plate 32 described later.

[0025] Further, the first bottom plate portion 31B is formed at two locations for one first regulating portion 31A. Each first bottom plate portion 31B is formed in a rectangular shape when viewed from above (as viewed from above), with a base portion formed integrally with the first regulating portion 31A and formed to extend in the width direction toward the tip. The upper surface 31Ba of the first bottom plate portion 31B is disposed so as to be substantially flush with the document loading surface 121a of the document tray 121, and forms the document loading surface. The width direction length of the first bottom plate portion 31B will be described in detail later.

[0026] As shown in Fig. 6(a) and Fig. 6(b), the first slider portion 31C is integrally formed with the first regulating portion 31A and the first bottom plate portion 31B so as to protrude downward on the side opposite to the upper surface 31Ba of the first bottom plate portion 31B. On the other hand, as shown in Fig. 5(a), the document tray 121 is formed with a guide groove portion 121c having a groove shape (slit shape) with the width direction as the longitudinal direction. Also, the document tray 121 is formed with a plurality of ribs 121b protruding upward in parallel with the guide groove portion 121c. As shown in Fig. 5(b), Fig. 6(a) and Fig. 6(b), the plurality of ribs 121b slide on the base side sliding portion 31Ab at the end of the width direction below the first regulating portion 31A and the tip side sliding portion 31Bb at the tip of the width direction below the first bottom plate portion 31B. Therefore, the first side regulating plate 31 is arranged to be movable (slidable) in the width direction relative to the document tray 121 by the first slider portion 31C being guided by the guide groove portion 121c while sliding on the upper surfaces of the multiple ribs 121b.

[0027] Similarly, the second side regulating plate 32 has a second regulating portion 32A, a second bottom plate portion 32B, and a second slider portion 32C, as shown in Figs. 4(a) and 6(a). The second regulating portion 32A is disposed so as to protrude upward from the document stacking surface 121a of the document tray 121, as shown in Figs. 4(a) and 4(b). The second regulating portion 32A is formed with a second regulating surface 32Aa that abuts against an end of the document in the width direction loaded on the document tray 121 to regulate the position of the document. The second regulating surface 32Aa is disposed facing inward between the first side regulating plate 31 and the second side regulating plate 32 so as to face the first regulating surface 31Aa of the first side regulating plate 31 described above.

[0028] The second bottom plate portion 32B is formed so as to be located at one position for one second regulating portion 32A and between the two second bottom plate portions 31B of the first regulating portion 31A in the feeding direction. The second bottom plate portion 32B is formed in a rectangular shape when viewed from above, and the base portion is formed integrally with the second regulating portion 32A and is formed so as to extend in the width direction toward the tip. The upper surface 32Ba of the second bottom plate portion 32B is disposed so as to be substantially the same plane as the document loading surface 121a of the document tray 121, and forms the document loading surface. The details of the width direction length of the second bottom plate portion 32B will be described later.

[0029] As shown in Figs. 6(a) and 6(b), the second slider portion 32C is integrally formed with the second regulating portion 32A and the second bottom plate portion 32B so as to protrude downward on the side opposite to the upper surface 32Ba of the second bottom plate portion 32B. As described above, the document tray 121 is formed with the guide groove portion 121c, and also with a plurality of ribs 121b. As shown in Figs. 5(b), 6(a) and 6(b), the base side sliding portion 32Ab at the end of the width direction below the second regulating portion 32A and the tip side sliding portion 32Bb at the tip of the width direction below the second bottom plate portion 32B slide on the plurality of ribs 121b. Therefore, the second side regulating plate 32 is arranged to be movable (slidable) in the width direction relative to the document tray 121 by the second slider portion 32C being guided by the guide groove portion 121c while sliding on the upper surfaces of the plurality of ribs 121b.

[0030] As shown in Figs. 5(b), 6(a) and 6(b), the interlocking mechanism 50 is configured with a rack and pinion mechanism disposed inside the document tray 121. The interlocking mechanism 50 is configured with a first rack 51, a second rack 52, a pinion 53 and a support plate 54. The first rack 51 is connected to one of the first slider parts 31C of the first side regulating plate 31, and the second rack 52 is connected to the second slider part 32C of the second side regulating plate 32. The first rack 51 and the second rack 52 are disposed on the back side of the document tray 121 because the first slider part 31C and the second slider part 32C pass through the guide groove part 121c, respectively. The pinion 53 has its central axis supported by a support plate 54 fixed to the back side of the document tray 121, and is engaged with the first rack 51 and the second rack 52. As a result, as described above, by moving one of the first side regulating plate 31 and the second side regulating plate 32, the other moves in the width direction in conjunction with the first regulating surface 31Aa and the second regulating surface 32Aa. Therefore, the center of the document, both ends of which are regulated by the first regulating surface 31Aa and the second regulating surface 32Aa, is configured to be at the same position as the conveyance center.

[0031] [Regarding positional tolerance of control surfaces due to component tolerances] Next, the inclination of the first and second restricting surfaces 31Aa and 32Aa and the positional tolerance at their upper ends caused by the component tolerances of the first and second side restricting plates 31 and 32 will be described. First, a case will be described in which the widthwise length of the first and second bottom plate parts is formed to half the width of a business card so that both ends in the widthwise direction of the size of a business card can be restricted by the first and second restricting surfaces of the first and second side restricting plates. In the following description, the second side restricting plate will be described as an example for parts that are similar to those of the first and second side restricting plates, and the description of the first side restricting plate will be omitted.

[0032] 11(a) and 11(b) are diagrams showing an ADF that can set, for example, a size of a business card. In the ADF 10, a side regulating mechanism 530 having a first side regulating plate 531 and a second side regulating plate 532 is provided on the document tray 121. For example, when setting a business card on the document tray 121, it is necessary to move the first side regulating plate 531 and the second side regulating plate 532 from a position separated in the width direction shown in FIG. 11(b) to a position close to the width of the business card shown in FIG. 11(a). For this reason, the widthwise lengths of the first bottom plate portion 531B and the second bottom plate portion 532B of the first side regulating plate 531 and the second side regulating plate 532 are formed up to a central position (center line) B that is the center in the width direction, that is, half the width of the business card. The length of the first side regulating plate 531 and the second side regulating plate 532 in the feeding direction is formed to a general length L1 (see FIG. 12(b)).

[0033] However, if the width of the first bottom plate portion 531B and the second bottom plate portion 532B is short, the following problem occurs. As shown in FIG. 12(a), the second side regulating plate 532 has a base side sliding portion 532Ab at the second regulating portion 532A that slides against the document tray 121, and a tip side sliding portion 532Bb at the tip of the bottom plate portion 532B that slides against the document tray 121. It is assumed that a component tolerance d12 in the height direction occurs between the base side sliding portion 532Ab and the tip side sliding portion 532Bb. Then, when the width of the second bottom plate portion 532B is W11, the second regulating surface 532Aa of the second regulating portion 532A is inclined at an angle θ11, and a position error d11 occurs at the upper end of the second regulating surface 532Aa.

[0034] Here, if the first side regulating plate 531 also has a component tolerance d12 with respect to the base side sliding portion at the tip side sliding portion, a position error d11 occurs at the upper end of the first regulating surface 531Aa shown in FIG. 12(b). Then, assume that a stack of A4 size original documents S1 having a length LS1 in the feeding direction and a width WS1 in the width direction is set. Then, for the width WS1 of the original documents S1, the distance in the width direction at the upper ends of the first regulating surface 531Aa and the second regulating surface 532Aa is the distance "WS1+d11×2". Therefore, even if the original documents S1 set between the first side regulating plate 531 and the second side regulating plate 532 are regulated by the length L1 of the first regulating surface 531Aa and the second regulating surface 532Aa, a gap of a position error d11×2 occurs. Therefore, the angle θ12 of the original S1 is inclined at a maximum of tan θ=d11×2 / L1, that is, the skew that occurs from the start of feeding (initial skew) becomes large.

[0035] In addition, in the first side regulating plate 531 and the second side regulating plate 532, there may be a case where the part tolerance of the tip side sliding part is reversed with respect to the base side sliding part, that is, the tip side sliding part 532Bb is lower than the base side sliding part 532Ab (part tolerance -d12). In this case, the position error of the upper end of the first regulating surface 531Aa and the second regulating surface 532Aa becomes the position error -d11, that is, the upper end is inclined inward. In this case, when setting the stack of documents S1, if the user strongly presses the first side regulating plate 531 and the second side regulating plate 532 inward, the documents S1 above the stack are strongly clamped and become a transport load. Then, there is a risk of a transport failure in which the pickup roller 111 cannot transport the documents. Furthermore, if the user does not press the first and second side regulating plates 531 and 532 inward strongly when setting the stack of originals S1, the position error of the lower ends of the first and second regulating surfaces 531Aa and 532Aa becomes the position error d11. Therefore, as described above, the skew (initial skew) that occurs from the start of feeding below the stack of originals S1 becomes large.

[0036] Next, the inclination of the first and second restricting surfaces 31Aa and 32Aa and the positional tolerance at their upper ends caused by the component tolerances of the first and second side restricting plates 31 and 32 in the first embodiment will be described. The width direction length of the first bottom plate portion 31B and the second bottom plate portion 32B of the first and second side restricting plates 31 and 32 in the first embodiment is formed to a length W1, which is the width of a business card, for example, as shown in Fig. 7(a). In short, it is formed to a length twice the length of the second bottom plate portion 532B shown in Fig. 12(a).

[0037] That is, the first bottom plate portion 31B and the second bottom plate portion 32B are formed alternately at different positions in the feeding direction. Therefore, when the first side regulating plate 31 and the second side regulating plate 32 are closest to each other, the tip of the first bottom plate portion 31B abuts against the second regulating surface 32Aa, and the tip of the second bottom plate portion 32B abuts against the first regulating surface 31Aa. In other words, the first bottom plate portion 31B and the second bottom plate portion 32B are formed so that a part (about half) thereof exceeds the central position B, which is the center in the width direction, when the first side regulating plate 31 and the second side regulating plate 32 are closest to each other. Therefore, when the first side regulating plate 31 and the second side regulating plate 32 are closest to each other, the first bottom plate portion 31B and the second bottom plate portion 32B are configured to overlap each other when viewed from the feeding direction.

[0038] In the second side regulating plate 32 thus configured, as shown in FIG. 7(a), a component tolerance d2 in the height direction is generated between the base side sliding portion 32Ab of the portion sliding with the document tray 121 and the tip side sliding portion 32Bb of the portion sliding with the document tray 121. Then, since the width direction length of the second bottom plate portion 32B is W1, the second regulating surface 32Aa of the second regulating portion 32A is inclined at an angle θ1, and only a position error d1 is generated at the upper end of the second regulating surface 32Aa whose height direction length is W2. That is, it is assumed that the component tolerance d2 is the same as the component tolerance d12 (see FIG. 12(a)) and the height direction length W2 is the same. Then, since the width direction length W1 of the second bottom plate portion 32B is double the length W11, the angle θ1 is half the angle θ11, and the position error d1 is also half the position error d11.

[0039] Similarly, even if the tip-side sliding portion 31Bb (see FIG. 5B) of the first side regulating plate 31 has a component tolerance d12 with respect to the base-side sliding portion 31Ab, the position error occurring at the upper end of the first regulating surface 31Aa shown in FIG. 7B is the position error d1. Suppose that a stack of A4-sized original documents S1 having a length LS1 in the feeding direction and a width WS1 in the width direction is set. Then, for the width WS1 of the original documents S1, the widthwise distance at the upper end between the first regulating surface 31Aa and the second regulating surface 32Aa is a distance "WS1+d1×2", which is half of the above-mentioned distance "WS1+d11×2". Therefore, the original documents S1 set between the first side regulating plate 31 and the second side regulating plate 32 is regulated by the length L1 of the first regulating surface 31Aa and the second regulating surface 32Aa, and a gap of the position error d1×2 occurs, which is half of the above-mentioned position error d11×2. Therefore, the angle θ2 of the original S1 is at most equal to the inclination of tan θ=d11×2 / L1, that is, the skew (initial skew) that occurs from the start of feeding is reduced.

[0040] In addition, in the first side regulating plate 31 and the second side regulating plate 32, there may be a case where the part tolerance of the tip side sliding part is reversed with respect to the base side sliding part, that is, the tip side sliding part 32Bb is lower than the base side sliding part 32Ab (part tolerance is -d2). Even in this case, the position error of the upper end of the first regulating surface 31Aa and the second regulating surface 32Aa becomes the position error -d1, that is, the upper end is inclined inward. However, even if the user strongly presses the first side regulating plate 31 and the second side regulating plate 32 inward when setting the stack of documents S1, the distance at which the documents S1 above the stack are strongly clamped is half, and the transport load is reduced. This also reduces the occurrence of transport failures in which the pickup roller 111 cannot transport the documents. Furthermore, if the user does not press the first and second side regulating plates 31 and 32 inward strongly when setting the stack of documents S1, the position error of the lower ends of the first and second regulating surfaces 31Aa and 32Aa will be the position error d1. Even in this case, the gap that occurs in the width direction of the documents S1 below the stack will be the position error d1×2, and the skew that occurs below the stack of documents S1 from the start of feeding will be reduced.

[0041] As described above, the first bottom plate portion 31B and the second bottom plate portion 32B are formed so as to exceed the center position B (see FIG. 4(b)) of the first and second restricting surfaces 31Aa and 32Aa when the first and second restricting surfaces 31Aa and 32Aa are closest to each other. That is, the tip of the first bottom plate portion 31B is located on the second restricting surface 32Aa side beyond the center position B, and the tip of the second bottom plate portion 32B is located on the first restricting surface 31Aa side beyond the center position B.

[0042] As a result, the length of the base side sliding parts 31Ab, 32Ab and the tip side sliding parts 31Bb, 32Bb at both ends of the parts of the first side regulating plate 31 and the second side regulating plate 32 that slide on the document tray 121 is defined as a length W1. Then, the length W1 can be made longer than the half length W11 of the state in which the first regulating surface 31Aa and the second regulating surface 32Aa are closest to each other. Therefore, even if there is a part tolerance d2 between the base side sliding parts 31Ab, 32Ab and the tip side sliding parts 31Bb, 32Bb, the inclination angle θ1 of the first regulating surface 31Aa and the second regulating surface 32Aa can be made small. This makes it possible to reduce the position error d1 of the upper ends of the first regulating surface 31Aa and the second regulating surface 32Aa. Therefore, when the first regulating surface 31Aa and the second regulating surface 32Aa are inclined inward, the transport resistance of the set document can be reduced, and the occurrence of transport failure can be reduced. Furthermore, when the first and second restricting surfaces 31Aa and 32Aa are inclined outward, the inclination of the set document relative to the feeding direction can be reduced, and the occurrence of skew during feeding can be reduced. This reduces the inclination of the image read by the front-side reading unit 104 and the back-side reading unit 105, and prevents the reading quality from deteriorating.

[0043] <Second embodiment> Next, a second embodiment, which is a partial modification of the first embodiment, will be described with reference to Figures 8(a) and 8(b). In the description of the second embodiment, the same reference numerals are used for the same parts as those in the first embodiment, and the description thereof will be omitted.

[0044] In the second embodiment, the shapes of the first bottom plate portion and the second bottom plate portion are changed compared to the first embodiment. In detail, as shown in Fig. 8(a) and Fig. 8(b), the side regulating mechanism 130 in the second embodiment has a first side regulating plate 131 and a second side regulating plate 132, similar to the first embodiment. Similarly, the first side regulating plate 131 has a first regulating portion 131A having a first regulating surface 131Aa and a first bottom plate portion 131B, and the second side regulating plate 132 has a second regulating portion 132A having a second regulating surface 132Aa and a second bottom plate portion 132B.

[0045] The first bottom plate portion 131B and the second bottom plate portion 132B in the second embodiment are each formed as one piece, formed in a rectangular shape when viewed from above, and disposed at different positions in the feeding direction. When the first regulating surface 131Aa and the second regulating surface 132Aa are closest to each other, the tips of the first bottom plate portion 131B and the second bottom plate portion 132B exceed the center position B and have a widthwise length that abuts on the first regulating surface 131Aa and the second regulating surface 132Aa, respectively. That is, when the first regulating surface 131Aa and the second regulating surface 132Aa are closest to each other, the first bottom plate portion 131B and the second bottom plate portion 132B are shaped so that they overlap when viewed from the feeding direction, but do not overlap when viewed from the width direction. Therefore, as in the first embodiment, the inclination of the first regulating surface 131Aa and the second regulating surface 132Aa caused by the component tolerance is reduced, and the position error at their upper ends is also reduced.

[0046] Other than this, the configuration, operation, and effects of the second embodiment are similar to those of the first embodiment, so the description thereof will be omitted.

[0047] <Third embodiment> Next, a third embodiment, which is a partial modification of the first embodiment, will be described with reference to Figures 9(a) and 9(b). In the description of the third embodiment, the same reference numerals are used for the same parts as those in the first embodiment, and the description thereof will be omitted.

[0048] In the third embodiment, the shapes of the first bottom plate portion and the second bottom plate portion are changed compared to the first embodiment. In detail, as shown in Fig. 9(a) and Fig. 9(b), the side regulating mechanism 230 in the third embodiment has a first side regulating plate 231 and a second side regulating plate 232, similar to the first embodiment. Similarly, the first side regulating plate 231 has a first regulating portion 231A having a first regulating surface 231Aa and a first bottom plate portion 231B, and the second side regulating plate 232 has a second regulating portion 232A having a second regulating surface 232Aa and a second bottom plate portion 232B.

[0049] The first bottom plate portion 231B and the second bottom plate portion 232B in the third embodiment are each composed of two (plural), formed in a rectangular shape when viewed from above, and arranged alternately at different positions in the feeding direction, so-called comb-like. When the first regulating surface 231Aa and the second regulating surface 232Aa are closest to each other, the tips of the first bottom plate portion 231B and the second bottom plate portion 232B exceed the center position B and have a widthwise length that abuts on the first regulating surface 231Aa and the second regulating surface 232Aa, respectively. In other words, when the first regulating surface 231Aa and the second regulating surface 232Aa are closest to each other, the first bottom plate portion 231B and the second bottom plate portion 232B are shaped so that they overlap when viewed from the feeding direction, but do not overlap when viewed from the width direction. Therefore, similarly to the first embodiment, the inclination of the first restriction surface 231Aa and the second restriction surface 232Aa caused by component tolerances is reduced, and the position error at their upper ends is also reduced.

[0050] Other than this, the configuration, operation, and effects of the third embodiment are similar to those of the first embodiment, so the description thereof will be omitted.

[0051] <Fourth embodiment> Next, a fourth embodiment, which is a partial modification of the first embodiment, will be described with reference to Figures 10(a) and 10(b). In the description of the fourth embodiment, the same reference numerals are used for the same parts as those in the first embodiment, and the description thereof will be omitted.

[0052] In the fourth embodiment, the shapes of the first bottom plate portion and the second bottom plate portion are changed compared to the first embodiment. In detail, as shown in Fig. 10(a) and Fig. 10(b), the side regulating mechanism 330 in the fourth embodiment has a first side regulating plate 331 and a second side regulating plate 332, similar to the first embodiment. Similarly, the first side regulating plate 331 has a first regulating portion 331A having a first regulating surface 331Aa and a first bottom plate portion 331B, and the second side regulating plate 332 has a second regulating portion 332A having a second regulating surface 332Aa and a second bottom plate portion 332B.

[0053] In the fourth embodiment, the first bottom plate portion 331B and the second bottom plate portion 332B are each formed as one piece, and are formed in a triangular shape with the first regulating surface 331Aa or the second regulating surface 332Aa as the base when viewed from above. That is, the first bottom plate portion 331B and the second bottom plate portion 332B are formed in a so-called tapered shape in which the width in the feeding direction becomes smaller toward the tip side in the width direction. Then, in a state in which the first regulating surface 331Aa and the second regulating surface 332Aa are closest to each other, the tip ends of the first bottom plate portion 331B and the second bottom plate portion 332B have a widthwise length that exceeds the center position B and abuts against the first regulating surface 331Aa and the second regulating surface 332Aa, respectively. That is, the first bottom plate portion 331B and the second bottom plate portion 332B are shaped to overlap when viewed from the feeding direction with the first regulating surface 331Aa and the second regulating surface 332Aa closest to each other. Therefore, as in the first embodiment, the inclination of the first regulating surface 331Aa and the second regulating surface 332Aa caused by component tolerances is reduced, and the position error at their upper ends is also reduced.

[0054] Other than this, the configuration, operation, and effects of the fourth embodiment are similar to those of the first embodiment, so the description thereof will be omitted.

[0055] <Possibilities for other embodiments> In the above first to fourth embodiments, the first and second bottom plate portions both exceed the center position B when the first and second side regulating plates are closest to each other. However, this is not limiting, and only the first bottom plate portion (or the second bottom plate portion) may exceed the center position B. Even in this case, there is an effect of reducing the position error of the side that exceeds the center position B.

[0056] In the above first to fourth embodiments, the tip of the first bottom plate abuts against the second restriction surface and the tip of the second bottom plate abuts against the first restriction surface when the first side restriction plate and the second side restriction plate are closest to each other. However, the tip of the first bottom plate or the tip of the second bottom plate may be slightly beyond the center position B when the first side restriction plate and the second side restriction plate are closest to each other. Even in this case, there is an effect of reducing the position error compared to when the tip does not exceed the center position B. In other words, if at least a part of the first bottom plate and the second bottom plate exceeds the center position B when the first side restriction plate and the second side restriction plate are closest to each other, there is an effect of reducing the position error compared to when the tip does not exceed the center position B. In this case, the part where the first side restriction plate and the second side restriction plate abut against each other when the first side restriction plate and the second side restriction plate are closest to each other is not limited to the tip part of the first bottom plate or the second bottom plate. For example, it is possible to abut any part of the first bottom plate portion of the first side regulating plate (the second bottom plate portion of the second side regulating plate) against a predetermined part such as a protrusion of the document tray. It is also possible to abut a first rack (second rack) fixed to the first side regulating plate (second side regulating plate) against a predetermined part such as a protrusion of the document tray.

[0057] In the above first to third embodiments, the first and second bottom plate portions are rectangular when viewed from above, and in the fourth embodiment, the first and second bottom plate portions are triangular when viewed from above. However, the present invention is not limited to this, and any shape may be used as long as the first and second side regulating plates are not hindered from moving in the width direction and the tip of the first or second bottom plate portion exceeds the center position B. For example, the boundary between the first and second bottom plate portions when the first and second side regulating plates are closest to each other may be arc-shaped or stepped, and there may be a gap between the first and second bottom plate portions.

[0058] In the above first to fourth embodiments, the inclination of the first and second restricting surfaces and the position error of the upper ends thereof due to the component tolerances of the base side sliding portion and the tip side sliding portion of the first and second bottom plate portions have been described. However, the present invention is not limited to this, and may be, for example, a planar shape in which the sliding portion of the first and second bottom plate portions and the upper surface of the document tray come into surface contact. In other words, the present invention can be applied when the sliding portion of the first and second bottom plate portions has a shape in which the vertical heights of the base side and the tip side are different due to the component tolerances.

[0059] In the above first to fourth embodiments, a rack-and-pinion mechanism is used as the interlocking mechanism for interlocking the first and second side regulating plates. However, the present invention is not limited to this, and may be, for example, a mechanism for interlocking the first and second side regulating plates using a belt and pulley. In other words, any mechanism having the function of an interlocking mechanism may be used.

[0060] In the above first to fourth embodiments, the sheet feeding device is provided in the image reading device. However, the present invention is not limited to this, and may be a manual feed tray or a paper feed cassette equipped with a first side regulating plate and a second side regulating plate on which a sheet as a recording material can be set. Even in this case, the skew of the sheet is reduced, and it is possible to reduce deterioration of the positional accuracy when an image is formed on the sheet by the image forming engine 60, and to reduce conveyance failure. [Explanation of symbols]

[0061] 10...image reading device / 20...sheet feeding device (ADF) / 31...first regulating section (first side regulating plate) / 31Aa...first regulating surface / 31B...first bottom plate / 32...second regulating section (second side regulating plate) / 32Aa...second regulating surface / 32B...second bottom plate / 60...image forming section (image forming engine) / 100...image forming device (printer) / 104, 105...reading section (front side reading unit, back side reading unit) / 111...feeding section (pickup roller) / 121...loading tray (original tray)

Claims

1. a loading tray having a loading surface for loading sheets; a feeding section that feeds the sheets stacked on the stacking tray; a first regulating portion and a second regulating portion that are movable in a width direction perpendicular to a sheet feeding direction and that regulate a position in the width direction of the sheets loaded on the loading surface, the loading surface has a first slit extending in the width direction, and a second slit disposed at a position different from the first slit in the feeding direction and extending in the width direction, the first regulating portion has a first regulating surface that abuts against one end in the width direction of the sheet loaded on the loading surface, a first bottom plate portion that slides against an upper surface of the loading tray and supports the sheet together with the loading surface, and a first protruding portion that moves inside the first slit, the second regulating portion has a second regulating surface that abuts against the other end in the width direction of the sheet loaded on the loading surface, a second bottom plate portion that slides against an upper surface of the loading tray and supports the sheet together with the loading surface, and a second protruding portion that moves inside the second slit, the first bottom plate portion has a first inclined portion inclined with respect to the feeding direction such that an outer edge on the second regulating surface side in the width direction becomes more distant from the first regulating surface toward a downstream side in the feeding direction when viewed from above, the second bottom plate portion has a second inclined portion inclined with respect to the feeding direction so that an outer edge on the first regulating surface side in the width direction approaches the second regulating surface toward the downstream in the feeding direction when viewed from above, a first tip end portion of the first restricting portion that is located closest to the second restricting surface in the width direction and a second tip end portion of the second restricting portion that is located closest to the first restricting surface in the width direction are disposed at positions different from each other in the feeding direction, When the first and second restriction surfaces move from their farthest positions to their closest positions, the first and second tip portions pass a central position between the first and second restriction surfaces. A sheet feeding device comprising:

2. a loading tray having a loading surface for loading sheets; a feeding section that feeds the sheets stacked on the stacking tray; a first regulating portion and a second regulating portion that are movable in a width direction perpendicular to a sheet feeding direction and that regulate a position in the width direction of the sheets loaded on the loading surface, the loading surface has a first slit extending in the width direction, and a second slit provided at a position different from the first slit in the feeding direction and extending in the width direction, the first regulating portion has a first regulating surface that abuts against one end in the width direction of the sheet loaded on the loading surface, a first bottom plate portion that slides against an upper surface of the loading tray and supports the sheet together with the loading surface, and a first protruding portion that moves inside the first slit, the second regulating portion has a second regulating surface that abuts against the other end in the width direction of the sheet loaded on the loading surface, a second bottom plate portion that slides against an upper surface of the loading tray and supports the sheet together with the loading surface, and a second protruding portion that moves inside the second slit, the first bottom plate portion has a first inclined portion inclined with respect to the feeding direction such that an outer edge on the second regulating surface side in the width direction becomes more distant from the first regulating surface toward a downstream side in the feeding direction when viewed from above, the second bottom plate portion has a second inclined portion inclined with respect to the feeding direction so that an outer edge on the first regulating surface side in the width direction approaches the second regulating surface toward the downstream in the feeding direction when viewed from above, The first and second restricting portions do not overlap when viewed from the feeding direction at a position where the first and second restricting surfaces are farthest from each other, and at least partially overlap when viewed from the feeding direction at a position where the first and second restricting surfaces are closest to each other. A sheet feeding device comprising:

3. a linkage mechanism for linking and moving the first restriction portion and the second restriction portion in opposite directions to each other in the width direction, 3. The sheet feeding device according to claim 1, wherein the sheet feeding device is a sheet conveying device.

4. the interlocking mechanism includes a first rack portion connected to the first regulating portion via the first slit, a second rack portion connected to the second regulating portion via the second slit, and a pinion gear meshing with the first rack portion and the second rack portion.

4. The sheet feeding apparatus according to claim 3,

5. The loading surface has a plurality of ribs extending in the width direction and sliding on the first bottom plate portion and the second bottom plate portion.

5. The sheet feeding device according to claim 1, wherein the sheet feeding device is a sheet conveying device.

6. A sheet feeding device according to any one of claims 1 to 5, a reading unit that reads an image on the sheet fed by the sheet feeding device, 1. An image reading apparatus comprising:

7. The image reading device according to claim 6 , and an image forming unit that forms the image read by the image reading device on another sheet.

1. An image forming apparatus comprising:

8. A sheet feeding device according to any one of claims 1 to 5, an image forming unit that forms an image on the sheet fed by the sheet feeding device, 1. An image forming apparatus comprising:

Images