JP2012012184A - Sheet carrying device - Google Patents

Abstract

A sheet conveying apparatus capable of stabilizing the positioning accuracy in the width direction of a sheet placed on a placing surface.
A sheet transport apparatus 11 performs a predetermined process on a sheet 9 in the middle of a transport path 16 and a transport unit 42 that transports a sheet 9 on the supply tray 12 along the transport path 16. And a processing unit 25. The supply tray 12 includes a placement surface 12A for supporting the back surface 9A of the sheet 9, and a pair of positioning members 200A for positioning in the width direction across the sheet 9 from both sides in the width direction of the sheet 9 on the placement surface 12A. 200B. At least one of the positioning members 200 </ b> A and 200 </ b> B is movable in the width direction according to the width of the sheet 9. Guide portions 100A, 100B, and 100C that bulge upward or downward along the conveyance direction on the placement surface 12A and curve the sheet 9 placed on the placement surface 12A upward or downward along the conveyance direction. Is provided.
[Selection] Figure 4

Description

  The present invention relates to a sheet conveying apparatus.

  Patent Document 1 discloses an example of a conventional sheet conveying apparatus. The sheet conveying apparatus (see reference numeral 5 in FIG. 1 and the like) conveys a supply tray (see reference numeral 10 in FIG. 1 and the like) on which a sheet is placed and a sheet placed on the supply tray along a conveyance path. A conveyance section (see reference numerals 74 to 77 and 79 in FIG. 6) and a processing section (see reference numeral 78 in FIG. 6) for reading an image formed on the sheet in the middle of the conveyance path.

  The supply tray includes a mounting surface that supports the back surface of the sheet, and a pair of positioning members that perform positioning in the width direction across the sheet from both sides in the width direction that is perpendicular to the sheet conveyance direction on the mounting surface ( And the like (see reference numerals 80a and 80b in FIG. 1). Each positioning member is movable in the width direction according to the width of the sheet.

  In the conventional sheet conveying apparatus having the above configuration, the user moves each positioning member and presses the sheet against the sheet according to various sizes of sheets, thereby positioning the sheet placed on the placing surface in the width direction. I do. Thus, skew and paper jam when the sheet is conveyed toward the processing unit are suppressed.

JP 2006-117382 A

  However, in the conventional sheet conveying apparatus, when the positioning member moves in the width direction and stops against the sheet, pressure in the width direction acts on the sheet. In this case, if the sheet is thin or curled in the width direction (upward warping or downward warping), both end edges in the width direction of the sheet can easily escape upward or downward with respect to the positioning member. For this reason, there is a possibility that the pair of positioning members may come into contact with both edges in the width direction of the sheet in a positional relationship narrower than the original width direction size of the sheet, and the positioning in the width direction of the sheet placed on the placement surface It is difficult to stabilize accuracy. As a result, a sheet conveyed along the conveyance path from the placement surface is skewed or a paper jam occurs, and there is a problem in a predetermined process performed by the processing unit on the sheet in the middle of the conveyance path. Can occur. For example, if the processing unit is an image reading unit that reads an image formed on a sheet, a defect such as distortion may occur in the read image. Further, for example, if the processing unit is an image forming unit that forms an image on a sheet, the image formed on the sheet may be distorted and problems such as misalignment may occur.

  The present invention has been made in view of the above-described conventional situation, and an object thereof is to provide a sheet conveying apparatus capable of stabilizing the positioning accuracy in the width direction of the sheet placed on the placement surface. .

The sheet conveying apparatus of the present invention includes a supply tray on which a sheet is placed,
A transport unit that transports the sheet placed on the supply tray along a transport path;
A sheet conveying apparatus including a processing unit that performs a predetermined process on the sheet in the middle of the conveying path,
The supply tray is positioned in the width direction across the sheet from both the placement surface that supports the back surface of the sheet and the width direction that is a direction orthogonal to the sheet conveyance direction on the placement surface. A pair of positioning members
At least one of the positioning members is movable in the width direction according to the width of the sheet,
The placement surface is provided with a guide portion that bulges upward or downward along the transport direction and curves the sheet placed on the placement surface upward or downward along the transport direction. (Claim 1).

  In the sheet conveying apparatus of the present invention, a guide portion is provided on the mounting surface of the supply tray. The guide portion bulges upward or downward along the sheet conveyance direction, and curves the sheet placed on the placement surface upward or downward along the conveyance direction. For this reason, even when the sheet is thin or curled in the width direction, the sheet placed on the placement surface comes into contact with the guide portion, thereby forcibly moving the sheet upward or downward along the conveyance direction. Can be curved. Thereby, curling in the width direction of the sheet is corrected, and rigidity against pressure from the width direction of the sheet is improved. As a result, even if a pressure from the width direction acts on the sheet due to the movement of the positioning member in the width direction, both end edges in the width direction of the sheet can be prevented from escaping upward or downward with respect to the positioning member.

  Therefore, the sheet conveying apparatus of the present invention can stabilize the positioning accuracy in the width direction of the sheet placed on the placement surface. As a result, it is difficult for the processing unit to process the sheet.

  In addition, when the user moves the positioning member to position the sheet in the width direction, the positioning member can easily stop against the sheet whose rigidity against pressure from the width direction is improved. It becomes easy to carry out, and the work of placing the sheet on the placement surface becomes easy.

  In the sheet conveying device of the present invention, when the guide portion and each positioning member are viewed from the side in the width direction, the portion that bulges most upward or downward of the guide portion is disposed at a position overlapping each positioning member. It is desirable (Claim 2). According to this configuration, since the guide portion and each positioning member are in the above-described relative positional relationship, the guide portion corrects the curl in the width direction of the sheet in the vicinity of each positioning member, and from the width direction of the sheet. The rigidity against pressure can be improved. For this reason, even if the pressure from the width direction acts on the sheet by the movement of the positioning member in the width direction, the sheet can be reliably prevented from escaping upward or downward with respect to the positioning member. As a result, the positioning accuracy in the width direction of the sheet placed on the placement surface can be further stabilized.

  In the sheet conveying apparatus of the present invention, it is desirable that the guide portion is integrally formed on a surface of the positioning member that contacts the back surface of the sheet. According to this configuration, in the vicinity of the position where the positioning member applies pressure from the width direction to the sheet, the guide portion integrally formed with the positioning member corrects the curl in the width direction of the sheet, and the width direction of the sheet The rigidity with respect to the pressure from the can be improved. For this reason, it can prevent more reliably that a sheet | seat escapes upward or downward with respect to a positioning member, and can stabilize the positioning precision of the width direction of the sheet | seat mounted in a mounting surface more.

  In the sheet conveying apparatus of the present invention, the supply tray is preferably composed of a main tray and a sub-tray. The main tray preferably forms a range on the downstream side in the transport direction on the placement surface. The sub-tray is provided to be displaceable between a storage position overlapping the main tray and a deployment position extending from the main tray to the upstream side in the transport direction. It is preferable that the guide portion is formed on the mounting surface when the sub-tray that is configured and in the development position is inclined with respect to the main tray. According to this configuration, since the placement surface and the guide portion can be formed by the main tray and the sub tray, the width of the sheet can be obtained even for a long sheet in the transport direction without providing a dedicated guide portion. The rigidity against the pressure from the direction can be improved. As a result, the positioning accuracy in the width direction of the sheet placed on the placement surface can be stabilized.

  In the sheet conveying apparatus of the present invention, the processing unit is preferably an image reading unit that reads an image formed on the sheet. According to this configuration, problems such as distortion are not likely to occur in the image read by the processing unit which is an image reading unit.

  In the sheet conveying apparatus of the present invention, the processing unit is preferably an image forming unit that forms an image on a sheet. According to this configuration, the processing unit, which is an image forming unit, is distorted in the image formed on the sheet, and problems such as misalignment are less likely to occur.

FIG. 2 is a perspective view of an image processing apparatus to which the sheet conveying apparatus according to the first exemplary embodiment is applied (a state where the ADF is closed and the positioning members are most separated from each other). 1 is a top view of an image processing apparatus to which a sheet conveying apparatus according to a first exemplary embodiment is applied. 1 is a perspective view of an image processing apparatus to which a sheet conveying apparatus of Example 1 is applied (showing a sheet conveying apparatus in a state where an ADF is open). FIG. 3 is a cross-sectional view illustrating the AA cross section of FIG. 2 according to the sheet conveying apparatus of Embodiment 1. FIG. 2 is a perspective view of an image processing apparatus to which the sheet conveying apparatus according to the first exemplary embodiment is applied (a state where the ADF is closed and the positioning members are closest to each other). (A) And (b) is a schematic diagram explaining the effect | action of each positioning member and the guide part with respect to the sheet | seat mounted in a mounting surface, (C) is related with the sheet conveying apparatus of Example 1. It is a schematic diagram explaining the comparative example in which the guide part is not provided. FIG. 6 is a cross-sectional view illustrating a main tray and a sub-tray that constitute a supply tray in the sheet conveying apparatus according to the second exemplary embodiment ((a) illustrates a sub-tray in a storage position, and (b) illustrates a sub-tray in a development position. ). FIG. 10 is a schematic diagram of an image forming apparatus to which a sheet conveying apparatus of Example 3 is applied.

  Embodiments 1 to 3 embodying the present invention will be described below with reference to the drawings.

Example 1
As shown in FIG. 1, an automatic document feeder (ADF: Auto Document Feeder; hereinafter simply referred to as “ADF”) 11 as an example of a sheet conveying apparatus of the present invention is applied to an image processing apparatus 10. It is. In FIG. 1, the operation panel 3 side of the image processing apparatus 10 is defined as the front side of the apparatus, and the opposite side of the operation panel 3 is defined as the rear side of the apparatus. Further, when the device is viewed from the front side, the left hand side (left side toward the operation panel 3) is defined as the left side, and the opposite side is defined as the right side. . 2 are displayed in correspondence with the directions shown in FIG. 1. Hereafter, based on FIG. 1, each component with which the image processing apparatus 10 is provided is demonstrated.

1. As shown in FIGS. 1 to 3, the image processing apparatus 10 has a function of reading an image on a sheet and converting it into electronic data, and a data transmission function of transmitting the read electronic data to the outside ( For example, the image processing apparatus main body 20 and the ADF 11 are provided. The ADF 11 is disposed so as to cover the upper surface of the image processing apparatus main body 20. Although illustration is omitted, the rear lower end edge of the ADF 11 is supported so as to be swingable around a swing shaft that faces in the left-right direction with respect to the rear upper end edge of the image processing apparatus main body 20. Then, by performing an operation of lifting the front part of the ADF 11 upward or vice versa, the ADF 11 is displaced between a closed state as shown in FIG. 1 and an open state as shown in FIG. It is possible to make it. When the ADF 11 is opened, the upper surface of the image processing apparatus main body 20 is opened.

2. Image Processing Apparatus Main Body As shown in FIG. 1, an operation panel 3 is provided on the front side of the image processing apparatus main body 20. The operation panel 3 accepts input from the user and displays the processing status of the image processing apparatus 10 and the like. Although not shown in the figure, the image processing apparatus main body 20 is provided with a control unit and a power supply unit that control the ADF 11, the operation panel 3, and the like.

  As shown in FIGS. 3 and 4, a contact glass 22 is provided on the upper surface side of the image processing apparatus main body 20. The contact glass 22 is divided into a fixed reading glass 79 on the left side and a moving reading glass 80 on the right side, and a document separating member 81 to be described later is provided between the two.

  As shown in FIG. 4, an image reading unit 25 is provided below the contact glass 22 inside the image processing apparatus main body 20. As the image reading unit 25, a well-known image reading sensor such as a contact image sensor (CIS) or a charge coupled device (CCD) can be used. In this embodiment, a contact image sensor is used. . A slide shaft 78 extending in the left-right direction is fixed to the inner side surface of the housing of the image processing apparatus main body 20. The image reading unit 25 is slidably supported on the slide shaft 78 and is slid in the left-right direction along the slide shaft 78 by being driven by a driving mechanism (not shown) (for example, a pulley / belt mechanism). In the standby state, the image reading unit 25 is located below the left edge of the moving reading glass 80. As will be described later, the image reading unit 25 moves to the image reading position 18 and also functions as an image reading unit of the ADF 11.

  When a user places a single document or book on the moving reading glass 80 and wants to read an image of the surface (the surface facing the moving reading glass 80), that is, an automatic document of the ADF 11 When the transport function is not used, the image reading unit 25 reads an image formed on the surface of the document or the book while moving from below the left edge of the moving reading glass 80 to below the right edge. Then, the image read by the image reading unit 25 is transmitted to the control unit and converted into electronic data.

3. ADF
As shown in FIG. 4, the ADF 11 includes a base member constituted by a main body frame 30, an upper guide 34, and an under guide 36, and an upper cover 32 that covers the left portion of the upper guide 34 from above. .

  The main body frame 30 is a box-like body that constitutes the bottom and side walls of the ADF 11. A discharge tray 14 for discharging sheets is formed on the surface of the main body frame 30 facing upward.

The upper guide 34 is a plate-like body that extends upwardly with respect to the discharge tray 14. The left side of the upper guide 34 is supported by the main body frame 30 and covered with the upper cover 32. The right side of the upper guide 34 is a supply tray 12 on which a single sheet (for example, a document such as paper or an OHP sheet) or a plurality of stacked sheets are placed. The upper guide 34 extends from the supply tray 12 to the vicinity of a supply unit 50 (see FIG. 4), which will be described later, and constitutes a part of the first conveyance path 26, which will be described later.

  The under guide 36 is a substantially plate-like body that extends from below a main roller 64 to be described later to the vicinity of a discharge unit 70 to be described later and constitutes a part of a second transport path 28 to be described later.

  Further, the ADF 11 takes out one sheet or a plurality of sheets 9 placed on the supply tray 12 one by one, automatically conveys them along the conveyance path 16, and discharges them to the discharge tray 14. An image reading unit 25 that reads an image of the surface 9B of the sheet 9 in the middle of the conveyance path 16 (when the sheet 9 is placed on the supply tray 12, the surface facing upward is referred to as the surface 9B, and the surface 9B is The opposite surface is the back surface 9A). As will be described later, the image reading unit 25 moves to the image reading position 18 below the fixed reading glass 79 and stops when the ADF 11 is operated, and the image reading unit 25 of the ADF 11 (the “processing” of the present invention). Function as an example).

3.1. Supply Tray As shown in FIGS. 1, 2, and 4, the supply tray 12 has a rectangular plate shape with a size on which sheets of various sizes can be placed, and is inclined downward toward the left side. The upper surface of the supply tray 12 is a placement surface 12 </ b> A that supports the back surface 9 </ b> A of the sheet placed on the supply tray 12.

  In the present embodiment, the placement surface 12A refers to the leading end of the sheet 9 placed on the supply tray 12 when the sheet 9 is inserted to a position where the sheet 9 can be fed by the sheet feeding unit 50. This is the surface that supports the back surface 9A of the sheet 9 when it is at a position detected by the sheet detection sensor 151 (see FIG. 4). In FIG. 4, the surface on the right side of the upper surface of the upper guide 34 from the sheet detection sensor 151 is the placement surface 12A.

  A pair of positioning members 200A and 200B are provided on the mounting surface 12A. Each positioning member 200A, 200B includes a partition portion 202A, 202B and a base portion 201A, 201B.

  The partition sections 202A and 202B are located outside the width direction (front-rear direction of the apparatus), which is a direction orthogonal to the conveyance direction of the sheet 9 in the supply tray 12 (a direction along a conveyance path 16 described later). These are plate-like members that extend in the conveying direction and project upward, and face each other.

  The base portions 201A and 201B are plate-like members that extend from the lower end edges of the partition portions 202A and 202B toward the center side in the width direction of the supply tray 12 so as to approach each other. The lengths of the bases 201A and 201B in the conveyance direction of the sheet 9 are set to be as long as the partitions 202A and 202B. The lower surfaces of the base portions 201A and 201B are opposed to the mounting surface 12A of the supply tray 12, and the upper surfaces of the base portions 201A and 201B are curved surfaces that draw a gentle arc upward along the conveyance direction of the sheet 9. It is said that. The upper surfaces of the base portions 201A and 201B are guide portions 100A and 100B.

  On the placement surface 12A, rail grooves 205A and 205B for guiding the base portions 201A and 201B in the width direction of the sheet 9 are cut out. A well-known rack gear mechanism is provided below the rail grooves 205A and 205B to move the base portions 201A and 201B in the width direction in conjunction with each other. By this rack gear mechanism, the base portion 201A and the partition portion 202A, and the base portion 201B and the partition portion 202B are overlapped with the central axis of the mounting surface 12A (the AA cross section in FIG. 2 overlaps the central axis of the mounting surface 12A. .) Is always maintained at an equal interval. Positioning members 200A and 200B (shown by a solid line in FIG. 2) shown in FIG. 1 are located at positions farthest from each other, corresponding to the maximum size sheet that can be handled by the ADF 11. On the other hand, the positioning members 200A and 200B (shown by a two-dot chain line in FIG. 2) shown in FIG. 5 are located closest to each other, corresponding to the smallest size sheet that the ADF 11 can handle.

  In the center of the mounting surface 12A in the width direction, a bulging portion 201C that has a width that does not interfere with the base portions 201A and 201B that move in the width direction and bulges upward is integrally formed. Similarly to the upper surfaces of the base portions 201A and 201B, the upper surface of the bulging portion 201C is also a curved surface that draws a gentle arc upward along the sheet 9 conveyance direction. The upper surface of the bulging portion 201C is the guide portion 100C.

  In FIG. 4, the guide portion 100A is located on the front side of the paper with respect to the guide portion 100C, and the guide portion 100B is located on the back side of the paper. When the placement surface 12A is viewed from the side in the front-rear direction of the apparatus, the curved shapes of the guide portions 100A, 100B, and 100C are the same, and the portion 101 that bulges most above the guide portions 100A, 100B, and 100C It is disposed at a position overlapping the positioning members 200A and 200B. Accordingly, the guide portions 100A, 100B, and 100C are configured to bend the sheet 9 placed on the placement surface 12A upward along the conveyance direction.

  Each of the positioning members 200A and 200B having such a configuration moves in the width direction of the sheet 9, and the partition portions 202A and 202B come into contact with both end edges in the width direction of the sheet 9, thereby sandwiching the sheet 9 from both ends. Thus, the sheet 9 can be positioned in the width direction. At this time, the sheet 9 is positioned with reference to the central axis of the placement surface 12A.

3.2. As shown in FIG. 4, in the transport unit 42, the transport path 16 is continuous with the first transport path 26 extending leftward from the supply tray 12 and the first transport path 26, and downwards in an arc shape. A curved conveyance path 27 that is curved and a second conveyance path 28 that is continuous with the curved conveyance path 27 and extends in the upper right direction toward the discharge tray 14 are configured.

  The left end portion of the upper cover 32 is swingably supported by the left end portion of the main body frame 30. Although illustration is omitted, by lifting the right end portion of the upper cover 32 upward, the upper side of the first conveyance path 26 is opened, and it is possible to deal with problems such as sheet jamming.

  A plurality of reinforcing ribs 191 and 192 are provided inside the upper cover 32. Each of the reinforcing ribs 191 and 192 protrudes downward in a state in which the upper cover 32 is closed, and extends from the right end portion to the left end portion of the upper cover 32. The reinforcing ribs 191 and 192 of the upper cover 32 guide the upper surface of the sheet conveyed from the supply tray 12 side, and constitute a part of the first conveyance path 26 and the curved conveyance path 27.

  A main roller 64 described later is disposed below the left end portion of the main body frame 30 and the left end portions of the reinforcing ribs 191 and 192 of the upper cover 32. The inner wall surface on the left end side of the main body frame 30 and the left end portions of the reinforcing ribs 191 and 192 of the upper cover 32 and the outer peripheral surface of the main roller 64 are transported through the first transport path 26 and further toward the downstream side in the transport direction. Guides the conveyed sheet. That is, the inner wall surface on the left end side of the main body frame 30 and the left end portions of the reinforcing ribs 191 and 192 of the upper cover 32 and the outer periphery of the main roller 64 constitute the curved conveyance path 27.

  The lower inner wall surface of the main body frame 30 and the under guide 36 guide a sheet conveyed along the curved conveyance path 27 and conveyed toward the sheet discharge tray 14. That is, the lower inner wall surface of the main body frame 30 and the under guide 36 constitute a second transport path 28. As shown in FIGS. 3 and 4, an opening 84 is provided in the lower surface 31 of the main body frame 30 of the ADF 11. The opening 84 is located in the vicinity of the boundary between the second conveyance path 28 and the curved conveyance path 27. The sheet conveyed through the second conveyance path 28 is exposed toward the main body 20 when passing above the opening 84.

  The sheet conveyed from the curved conveyance path 27 to the second conveyance path 28 passes through the fixed reading glass 79 provided in the main body portion 20 through the opening 84. At this time, the document separating member 81 provided between the fixed reading glass 79 and the moving reading glass 80 scoops up the sheet conveyed while in contact with the fixed reading glass 79 from the fixed reading glass 79, 2 Guidance is reliably given to the conveyance path 28.

  Further, as shown in FIG. 4, the transport unit 42 includes a supply unit 50, a transport unit 60, and a discharge unit 70 described in detail below.

3.2.1. Supply Unit The supply unit 50 is provided on the downstream side of the supply tray 12 in the sheet conveyance direction, takes out the sheets 9 placed on the supply tray 12 one by one in order from the top, and conveys them downstream. Is. The supply unit 50 includes a suction roller 52 provided above the upper guide 34, a separation roller 54, and a separation pad 57.

  The separation roller 54 is provided at the center of the first rotation shaft 56 whose front end and rear end are rotatably supported by the main body frame 30. The first rotating shaft 56 is driven by a drive source 99 (see FIG. 2) including an electric motor and a large number of gears, and rotates in a predetermined rotation direction (clockwise in FIG. 4). Along with this, the separation roller 54 also rotates integrally with the first rotation shaft 56.

  A holder 58 is swingably supported on the first rotating shaft 56. The holder 58 extends to the supply tray 12 side while surrounding the separation roller 54, and supports the suction roller 52 so that the suction roller 52 can rotate. The suction roller 52 is connected to the first rotation shaft 56 via a gear group (not shown) disposed inside the holder 58. Thus, when the first rotation shaft 56 rotates, not only the separation roller 54 but also the suction roller 52 rotates clockwise. Along with this, the holder 58 swings so as to push down the suction roller 52 toward the lower upper guide 34.

  A separation pad 57 is disposed at a position facing the separation roller 54. The separation pad 57 is pressed against the outer peripheral surface of the separation roller 54 from below. The separation pad 57 is typically made of a cork piece, and is in sliding contact with the back surface 9A of the sheet passing above the separation pad 57 to exert a large frictional force against the sheet.

  The suction roller 52 rotates while being in contact with the surface 9B of the sheet placed on the supply tray 12, and applies a conveying force to the sheet. The separation roller 54 applies a conveying force to the sheet by rotating while abutting against the surface 9B of the sheet conveyed by the suction roller 52. At this time, when a plurality of sheets try to pass between the separation roller 54 and the separation pad 57, only the uppermost sheet in contact with the separation roller 54 is separated by the frictional force of the separation pad 57, and the sheet is separated. It is transported downstream in the transport direction. That is, the sheet is conveyed between the suction roller 52 and the upper guide 34 and between the separation roller 54 and the separation pad 57, and the supply unit 50 includes the reinforcing ribs of the upper guide 34 and the upper cover 32. The first transport path 26 is configured in cooperation with 191, 192, and the like.

3.2.2. Conveying Unit The conveying unit 60 conveys the sheets taken out from the supply tray 12 one by one by the supply unit 50 along the first conveying path 26, the curved conveying path 27, and the second conveying path 28. The conveyance unit 60 includes a conveyance roller 61 provided on the left side of the separation roller 54 (on the downstream side of the separation roller 54 in the conveyance direction in the middle of the first conveyance path 26), and a pinch roller 65 facing the conveyance roller 61. is doing. The transport unit 60 includes a main roller 64 provided in the curved transport path 27 and pinch rollers 62 and 63 facing the main roller 64.

  The transport roller 61 is provided at the center of the second rotating shaft 66 whose front end and rear end are rotatably supported by the main body frame 30. Similarly to the first rotation shaft 56, the second rotation shaft 66 is driven by the drive source 99 and rotates in a predetermined rotation direction (clockwise in FIG. 4). Along with this, the transport roller 61 also rotates integrally with the second rotation shaft 66.

  The sheet conveyed by the separation roller 54 is nipped by the conveyance roller 61 and the pinch roller 65. The conveying roller 61 imparts a conveying force to the sheet by rotating while contacting the surface 9B of the conveyed sheet. That is, the transport roller 61 and the pinch roller 65 also constitute the first transport path 26.

  The main roller 64 is provided on a third rotating shaft 67 whose front end and rear end are rotatably supported by the main body frame 30. Similar to the first and second rotary shafts 56 and 66, the third rotary shaft 67 is driven by the drive source 99 and rotates in a predetermined rotation direction (counterclockwise in FIG. 4). Along with this, the main roller 64 also rotates integrally with the third rotation shaft 67.

  Thereafter, the sheet conveyed by the conveying roller 61 is nipped by the main roller 64 and the pinch roller 62 and further nipped by the main roller 64 and the pinch roller 63 on the downstream side in the sheet conveying direction. The main roller 64 rotates while being in contact with the back surface 9 </ b> A of the sheet, thereby applying a conveying force to the sheet and sending it to the downstream side of the second conveying path 28. That is, the main roller 64, the pinch roller 62, and the pinch roller 63 cooperate with the left end side inner wall surface of the main body frame 30 and the left end portions of the reinforcing ribs 191 and 192 of the upper cover 32 to form the curved conveyance path 27. ing.

3.2.3. Discharging Unit The discharging unit 70 discharges the sheet conveyed by the conveying unit 60 through the second conveying path 28 to the discharging tray 14. The discharge unit 70 includes a discharge roller 72 and a pinch roller 74 provided at the right end of the under guide 36 (the most downstream side of the second transport path 28). The discharge roller 72 is provided on a fourth rotation shaft 71 whose front end and rear end are rotatably supported by the main body frame 30. The fourth rotation shaft 71 is driven by the drive source 99 and rotates in a predetermined rotation direction (counterclockwise in FIG. 4), similarly to the first, second, and third rotation shafts 56, 66, and 67. Along with this, the discharge roller 72 also rotates integrally with the fourth rotating shaft 71. Then, the sheet sent along the second conveyance path 28 is nipped by the discharge roller 72 and the pinch roller 74 and discharged to the discharge tray 14. That is, the discharge roller 72 and the pinch roller 74 constitute the second transport path 28 in cooperation with the lower inner wall surface of the main body frame 30 and the under guide 36.

3.3. Image Reading Unit During ADF Operation The image reading unit 25 moves to a predetermined image reading position 18 (see FIG. 4) and stops when the ADF 11 operates. In this state, the upper surface side of the image reading unit 25 faces the second conveyance path 28 through the opening 84. The sheet conveyed by the conveyance unit 60 reaches the image reading position 18 on the upper surface of the fixed reading glass 79 through the opening 84, and at this time, the sheet surface 9B passes through the upper surface side of the image reading unit 25. It has become. Thereafter, the sheet is scooped up from the fixed reading glass 79 by the document separating member 81.

  A white member 82 is provided on the opposite side of the image reading unit 25 waiting at the image reading position 18 with the fixed reading glass 79 interposed therebetween. The white member 82 is elastically biased toward the image reading unit 25 waiting at the image reading position 18 by a coil spring. The sheet conveyed along the second conveyance path 28 passes through the upper surface side of the image reading unit 25 while being pressed against the image reading unit 25 side by the white member 82. As a result, the image reading unit 25 reads an image formed on the surface 9B of the sheet. Then, the image read by the image reading unit 25 is transmitted to the control unit and converted into electronic data.

3.4. Sheet Detection Member As shown in FIG. 4, the upper guide 34 is provided with a sheet detection sensor 151 that is positioned between the suction roller 52 and the separation roller 54 and protrudes so as to intersect the first conveyance path 26. ing. The sheet detection sensor 151 has a well-known configuration including a movable member that contacts and displaces the sheet, and a photo interrupter that detects the displacement of the movable member. When the sheet 9 is placed on the supply tray 12 and the leading end of the sheet 9 is inserted into the sheet feeding unit 50, the sheet detection sensor 151 inserts the sheet 9 into the sheet feeding unit 50 with respect to the control unit. A detection signal indicating that it has been made is transmitted.

3.5. Automatic Document Reading Operation of ADF As shown in FIG. 4, when the user places one or more sheets on the supply tray 12 and inserts the leading end of the sheet into the supply unit 50, the sheet detection sensor 151 is moved to the sheet. Is transmitted to the control unit.

  Then, after the user performs positioning in the width direction by sandwiching the sheet 9 from both sides in the width direction by the pair of positioning members 200A and 200B, the user operates the operation panel 3 to input the start of automatic document reading processing by the ADF 11. The control unit controls the conveyance unit 42 and the image reading unit 25 in the ADF 11 to start an automatic document reading process. Then, the sheets on the supply tray 12 are taken out one by one, conveyed along the conveyance path 16, and further turned upside down when passing through the curved conveyance path 27. Then, the image formed on the surface 9B of the sheet is read by the image reading unit 25. Thereafter, the sheet is discharged onto the discharge tray 14 with the surface 9 </ b> B down in the second conveyance path 28. This series of operations is automatically repeated until there are no more sheets on the supply tray 12.

<Effect>
In the ADF 11 according to the first embodiment, guide portions 100A, 100B, and 100C are provided on the placement surface 12A of the supply tray 12. Then, as shown in FIG. 4, the guide portions 100A, 100B, and 100C bulge upward along the sheet conveyance direction (the direction along the conveyance path 16) and are placed on the placement surface 12A. 9 is curved upward along the transport direction. Therefore, when the sheet 9 is thin or curled in the width direction (an example in which the sheet curls in the width direction is shown in FIG. 6 (a). However, when the sheet 9 placed on the placement surface 12A comes into contact with the guide portions 100A, 100B, and 100C, the sheet 9 is forcibly moved in the transport direction as shown in FIG. It can be curved upward along. As a result, as shown in FIG. 6B, curling in the width direction of the sheet 9 is corrected, and rigidity against pressure from the width direction of the sheet 9 is improved. As a result, even if the pressure F from the width direction acts on the sheet 9 due to the movement of the positioning members 200A and 200B in the width direction, both end edges in the width direction of the sheet 9 are above or below the positioning members 200A and 200B. It can prevent you from escaping.

  FIG. 6C shows a comparative example. If the placement surface 12A is not provided with the guide portions 100A, 100B, and 100C (the positioning members 200A and 200B are configured by only the partition portions 202A and 202B, and the placement surface 12A does not have the bulging portion 201C. ), When the sheet 9 curled in the width direction is made the mounting surface 12A, the sheet 9 is kept curled in the width direction as it is. In this state, when the pressure F from the width direction acts on the sheet 9 by the movement of the positioning members 200A and 200B in the width direction, both end edges in the width direction of the sheet 9 escape upward or downward with respect to the positioning members 200A and 200B. End up. In this case, the positioning members 200A and 200B cannot accurately position both ends of the sheet 9 in the width direction.

  As described above, the ADF 11 according to the first exemplary embodiment includes the guide portions 100A, 100B, and 100C on the placement surface 12A, thereby correcting the curl in the width direction of the sheet 9 placed on the placement surface 12A. 9 can be a curved shape along the conveying direction. For this reason, the rigidity of the both ends of the width direction of the sheet | seat 9 can be improved, and positioning by positioning member 200A, 200B can be performed accurately. Further, it is possible to prevent the sheet conveyed along the conveyance path 16 from the placement surface 12A from being skewed or causing a paper jam, and as a result, the image reading unit 25 moves along the conveyance path 16 in the middle of the sheet. 9 is difficult to cause a problem (for example, image data is distorted and the image is distorted).

  When the user moves the positioning members 200A and 200B to position the sheet 9 in the width direction, as shown in FIG. 6B, the positioning member 200A is placed on the sheet 9 having improved rigidity against pressure from the width direction. 200B is easy to stop, so that the positioning of the positioning members 200A and 200B can be easily determined, and the placement work of the sheet 9 on the placement surface 12A is facilitated.

  Furthermore, in this ADF 11, as shown in FIG. 4, when the guide portions 100A, 100B, 100C, the positioning members 200A, 200B, and the placement surface 12A are viewed from the side in the front-rear direction of the apparatus (the paper surface of FIG. 4). The portion 101 that bulges most above the guide portions 100A, 100B, and 100C is disposed at a position that overlaps the positioning members 200A and 200B. For this reason, in the vicinity of each positioning member 200A, 200B, the guide portions 100A, 100B, 100C can correct the curl in the width direction of the sheet 9 and improve the rigidity against the pressure from the width direction of the sheet 9. Thereby, even if the pressure F from the width direction acts on the sheet 9 due to the movement of the positioning members 200A and 200B in the width direction, the sheet 9 can be more reliably prevented from escaping upward or downward with respect to the positioning member.

  Further, in the ADF 11, among the three guide portions 100A, 100B, and 100C, the guide portions 100A and 100B that are positioned on both ends in the width direction of the sheet 9 are the positions of the sheet 9 in the base portions 201A and 201B of the positioning members 200A and 200B. It is integrally formed on the surface that contacts the back surface 9A. That is, the upper surfaces of the base portions 201A and 201B are curved surfaces that draw a gentle arc upward, and the upper surfaces of the base portions 201A and 201B are guide portions 100A and 100B. For this reason, the guide portions 100A and 100B correct the curl in the width direction of the sheet 9 in the vicinity of the portion where the partition portions 202A and 202B of the positioning members 200A and 200B apply the pressure F from the width direction to the sheet 9, The rigidity with respect to the pressure from the width direction of the sheet 9 can be improved. For this reason, it can prevent more reliably that the sheet | seat 9 escapes upward or downward with respect to positioning member 200A, 200B. Further, the configuration of the guide portions 100A and 100B can be simplified.

(Example 2)
As shown in FIG. 7, the ADF as the sheet conveying apparatus of the second embodiment is obtained by changing the supply tray 12 of the ADF 11 of the first embodiment to a supply tray 12D including a main tray 12M and a sub-tray 12S. Other configurations of the ADF of the second embodiment are the same as those of the ADF 11 of the first embodiment. For this reason, only the supply tray 12D is illustrated, and other configurations are omitted. Further, in the supply tray 12D, the same components as those in the supply tray 12 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  In the ADF according to the second embodiment, the supply tray 12D includes a main tray 12M and a sub-tray 12S.

  In the main tray 12M, the right side of the supply tray 12 of the first embodiment is shortened, and a pair of support portions 12F are provided on both ends in the width direction of the right end edge (in FIG. 7, one support portion is provided). Although only 12F is illustrated, the other support portion 12F exists on the front side of the sheet. Other configurations (for example, the positioning members 200A and 200B and the guide portions 100A, 100B, and 100C) are the same as the supply tray 12 of the first embodiment.

  The sub-tray 12S is a plate-like body provided with a pair of supported portions 12G that are rotatably supported by the support portion 12F (in FIG. 7, only one supported portion 12G is illustrated, but on the front side of the sheet. Is the other supported portion 12G). The sub-tray 12S can be rotated around an axis parallel to the front-rear direction of the apparatus by a hinge including a support portion 12F and a supported portion 12G.

  As shown in FIG. 7A, the position where the sub-tray 12S overlaps the main tray 12M from above is an example of the “storage position” in the present invention. In this state, the size of the device in the left-right direction can be reduced, and space saving of the device when not in use can be achieved.

  On the other hand, as shown in FIG. 7B, the sub-tray 12S is rotated away from the main tray 12M, and the edge of the sub-tray 12S near the supported portion 12G is applied to the right edge of the main tray 12M. The stop position is an example of the “deployment position” in the present invention. In this development position, the sub-tray 12S is inclined upward with respect to the main tray 12M.

  When the sub-tray 12S is in the unfolded position, the placement surface 12E is formed by the upper surface of the main tray 12S and the upper surface of the sub-tray 12S. The main tray 12S constitutes a range on the downstream side in the conveyance direction on the placement surface 12E, and the sub-tray 12S constitutes a range on the upstream side in the conveyance direction on the placement surface 12E. By deploying the sub-tray 12S, the placement surface 12E can be lengthened in the transport direction, and it is easy to handle larger size sheets.

  Then, the sub-tray 12S in the unfolded position is inclined upward with respect to the main tray 12M, and the main tray 12M and the sub-tray 12S are bent downward in a substantially “<” shape, thereby lowering the mounting surface 12E downward. A bulging guide portion 100D is formed.

  In the ADF according to the second embodiment having such a configuration, guide portions 100A, 100B, and 100C and a guide portion 100D are provided on the placement surface 12E of the supply tray 12D. As shown in FIG. 7B, the guide portions 100A, 100B, and 100C on the main tray 12M side bulge upward along the sheet conveyance direction, and the sheet 9 placed on the placement surface 12E. Is curved upward along the conveying direction. Further, the guide portion 100D, which is a bent portion between the main tray 12M and the sub-tray 12S, bends downward along the sheet conveyance direction, and causes the sheet 9 placed on the placement surface 12E to be along the conveyance direction. To bend downward. That is, when viewed from the width direction of the sheet 9, the sheet 9 placed on the placement surface 12 </ b> E is curved in a substantially “S” shape. As a result, the rigidity of both ends of a large size sheet can be improved.

  Therefore, the ADF of the second embodiment can achieve the same effects as the ADF of the first embodiment.

  In the ADF of the second embodiment, the guide units 100A, 100B, and 100C may be omitted from the main tray 12M, and only the guide unit 100D between the main tray 12M and the sub-tray 12S may be provided. In this case, the sheet 9 placed on the placement surface 12E is curved downward along the transport direction. At this time, if each positioning member 200A, 200B has a shape extending to the guide part 100D, the sheet 9 can be positioned in the width direction in the vicinity of the guide part 100D, and the effects of the present invention can be reliably achieved.

  Further, the sub-tray 12S may be inclined downward with respect to the main tray 12M. In this case, a guide portion that is bent upward is formed between the sub-tray 12S and the main tray 12M. The sheet 9 placed on the placement surface 12E is curved upward along the transport direction by the upward guide portion.

(Example 3)
An image forming apparatus 11P according to the third embodiment is obtained by replacing the image reading unit 25 of the ADF 11 according to the first embodiment with an image forming unit 25P (an example of the “processing unit” in the present invention). Other configurations are the same as those of the ADF 11 of the first embodiment. For this reason, about the same structure as Example 1, the same code | symbol is attached | subjected and description is abbreviate | omitted or simplified.

  Also in this image forming apparatus 11P, the sheet 9 placed on the supply tray 12 contacts the guide portions 100A, 100B, and 100C and curves upward along the sheet conveyance direction (direction along the conveyance path 16). To do. Then, it is transported along the transport path 16 by the transport unit 42 and discharged to the discharge tray 14. At this time, an image forming process is performed on the sheet 9 by the image forming unit 25P in the middle of the conveyance path 16. The image forming unit 25P can employ any image forming method such as an ink jet method or an electrophotographic method.

  In the image forming apparatus 11P having such a configuration, as in the ADF 11 of the first embodiment, the positioning accuracy in the width direction of the sheet 9 placed on the placement surface 12A is stabilized by the guide portions 100A, 100B, and 100C. be able to. For this reason, it is possible to prevent the sheet conveyed from the placement surface 12A along the conveyance path 16 from being skewed or causing a paper jam, and as a result, the image forming unit 25P is located in the middle of the conveyance path 16. The image formed on the sheet 9 is not distorted and problems such as misalignment are unlikely to occur.

  In the above, the present invention has been described with reference to the first to third embodiments. However, the present invention is not limited to the first to third embodiments, and can be appropriately modified and applied without departing from the spirit of the present invention. Needless to say.

  For example, the shape of the guide portion may be a bent shape, a stepped shape, or a wavy shape when the placement surface 12A is viewed from the side in the front-rear direction of the apparatus. Further, the bulging portion 201C of the first embodiment may be a separate member from the supply tray 12 and may be assembled later, and the upper surface of the bulging portion 201C may be configured so that the mounting surface 12A becomes the front-back direction of the apparatus. When viewed from the side, it may be bent, stepped, or wavy.

  Further, although the placement surface 12A is the right side surface from the sheet detection sensor 151, the range of the placement surface 12A may be determined based on another configuration. For example, the placement surface 12A may be determined depending on the distance from the suction roller 51. May be defined.

  The present invention can be used for an image forming apparatus, an image reading apparatus, a multifunction peripheral, or the like.

DESCRIPTION OF SYMBOLS 9 ... Sheet, 12, 12D ... Supply tray, 16 ... Conveyance path, 42 ... Conveyance part 9B ... Sheet surface, 9A ... Sheet back surface, 12A, 12E ... Loading surface 25, 25P ... Processing part (25 ... Image reading Part, 25P ... image forming part)
11, 11P ... Sheet conveying device (11 ... ADF, 11P ... Image forming device)
200A, 200B ... positioning member, 100A, 100B, 100C ... guide part 101 ... part that bulges most upward or downward of the guide part 12M ... main tray, 12S ... sub-tray

Claims (6)

A supply tray on which sheets are placed;
A transport unit that transports the sheet placed on the supply tray along a transport path;
A sheet conveying apparatus including a processing unit that performs a predetermined process on the sheet in the middle of the conveying path,
The supply tray is positioned in the width direction across the sheet from both the placement surface that supports the back surface of the sheet and the width direction that is a direction orthogonal to the sheet conveyance direction on the placement surface. A pair of positioning members
At least one of the positioning members is movable in the width direction according to the width of the sheet,
The placement surface is provided with a guide portion that bulges upward or downward along the transport direction and curves the sheet placed on the placement surface upward or downward along the transport direction. A sheet conveying apparatus characterized by comprising:   2. When the guide part and each positioning member are viewed from the side in the width direction, the most bulging portion above or below the guide part is disposed at a position overlapping with each positioning member. The sheet conveying apparatus according to the description.   The sheet conveying apparatus according to claim 1, wherein the guide portion is integrally formed on a surface of the positioning member that contacts the back surface of the sheet. The supply tray includes a main tray and a sub-tray,
The main tray constitutes a range on the downstream side in the transport direction on the placement surface,
The sub-tray is provided to be displaceable between a storage position that overlaps the main tray and a development position that extends from the main tray to the upstream side in the conveyance direction, and the conveyance direction on the placement surface is at the development position. Configure the upstream range,
4. The sheet conveying apparatus according to claim 1, wherein the guide portion is formed on the placement surface when the sub-tray in the development position is inclined with respect to the main tray. 5.   The sheet conveying apparatus according to claim 1, wherein the processing unit is an image reading unit that reads an image formed on the sheet.   The sheet conveying apparatus according to claim 1, wherein the processing unit is an image forming unit that forms an image on the sheet.

Images