JP2016069091A - Sheet conveying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet conveying device that can separate and convey preferably sheets regardless of the type of the sheets.SOLUTION: A sheet conveying device 1 comprises a supporting part 6 that supports sheets SH and a conveying part 4 that conveys the sheets SH to be supported by the supporting part 6, in a predetermined conveying direction. The conveying part 4 has: a separating roller 42 that can rotate around a first shaft core X1 parallel to a width direction orthogonal to the conveying direction; a separating pad 20 that separates the sheets SH to be supported by the supporting part 6 one by one, in cooperation with the separating roller 42; and pressing means 29 that presses the separating pad 20 against the separating roller 42. The sheet conveying device 1 further comprises an attaching/detaching member 100 a state of which can be changed between an attached state where the member is attached to the conveying part 4 and a detached state where the member is detached from the conveying part 4 and changes pressing loads F1 acting on the separating pad 20 in the attached state.SELECTED DRAWING: Figure 12

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 includes a support unit and a conveying unit. The support part supports the sheet. The conveyance unit conveys the sheet supported by the support unit in a predetermined conveyance direction.

  More specifically, the transport unit includes a separation roller, a separation pad, and a pressing unit. The separation roller is rotatable around a first axis parallel to the width direction orthogonal to the conveyance direction. The separation pad separates the sheets supported by the support portion one by one in cooperation with the separation roller. The pressing means presses the separation pad toward the separation roller.

  In this sheet conveying apparatus, a braking force is generated between the separation roller and the separation pad due to a pressing load acting on the separation pad, and the braking force acts on the sheet. As a result, when a plurality of sheets are likely to be conveyed in a state of being overlapped by the separation roller, a braking force acts on the sheets other than the sheet that is in contact with the separation roller, and the sheets are one by one. To be separated.

JP 2011-73814 A

  By the way, generally, if the size, thickness, slipperiness, etc. of the sheet changes, the pressing load necessary for separating the sheets also changes. Specifically, the pressing load necessary for separating a sheet having a small width is low and sufficient as compared with the pressing load necessary for separating a sheet having a large width. In this regard, in the above conventional sheet conveying apparatus, a constant pressing load is applied to the separation pad by the pressing means regardless of the size, thickness, surface slipperiness, etc. of the sheet. Can cause various problems.

  For example, in this type of sheet conveying apparatus, consider a case where the pressing load of the pressing unit is determined based on a wide sheet, a thin sheet, a slippery sheet, or the like. In this case, a high pressing load always acts on the separation pad, and an excessive braking force tends to act on a small width sheet, a thick sheet, a non-slip sheet, or the like. Then, the conveyance speed of the sheet separated and conveyed by the separation roller is likely to fluctuate.

  On the other hand, in this sheet conveying apparatus, a case is considered in which the pressing load of the pressing unit is determined based on a narrow sheet, a thick sheet, a non-slip sheet, or the like. In this case, the braking force acting on a wide sheet, a thin sheet, a slippery sheet or the like tends to be too small. Then, there is a problem that a sheet other than the sheet that comes into contact with the separation roller slides with respect to the separation pad, the separation performance is deteriorated, and double feeding is likely to occur.

  The present invention has been made in view of the above-described conventional situation, and an object of the present invention is to provide a sheet conveying apparatus that can separate and convey a sheet satisfactorily regardless of the type of the sheet.

The sheet conveying apparatus of the present invention includes a support unit for supporting a sheet,
A conveyance unit that conveys the sheet supported by the support unit in a predetermined conveyance direction, and the conveyance unit is a separation roller that is rotatable around a first axis parallel to a width direction orthogonal to the conveyance direction; ,
A separation pad that separates the sheets supported by the support portion one by one in cooperation with the separation roller;
Pressing means for pressing the separation pad toward the separation roller,
It further includes a detachable member that can be changed between a mounted state attached to the transport unit and a detached state detached from the transport unit, and changes a pressing load acting on the separation pad in the mounted state. It is characterized by.

  In the sheet conveying apparatus of the present invention, the pressing load acting on the separation pad is changed depending on whether the detachable member is in the mounted state or in the detached state. The configuration for changing the pressing load includes a configuration for reducing the pressing load when the detachable member is in the mounted state with respect to the pressing load when the detachable member is in the detached state, and a case where the detachable member is in the detached state. A configuration in which the pressing load when the detachable member is in the mounted state with respect to the pressing load is increased is included. A pressing load suitable for the conveyed sheet can be applied to the separation pad by appropriately changing whether the detachable member is in the mounted state or the detached state according to the type of the sheet.

  Therefore, in the sheet conveying apparatus of the present invention, the sheets can be well separated and conveyed regardless of the type of the sheet.

1 is a perspective view of an image reading apparatus according to Embodiment 1. FIG. FIG. 3 is a partial perspective view mainly showing a support portion, a pair of guides, and the like according to the image reading apparatus of Embodiment 1. FIG. 3 is a partial perspective view showing a state in which an outer cover on the upper left side is removed from FIG. 2. 1 is a partial cross-sectional view of an image reading apparatus according to Embodiment 1. FIG. FIG. 3 is a partial perspective view mainly showing a base, a separation pad, a separation pad holding unit, a pressing unit, and the like according to the image reading apparatus of Embodiment 1. 1 is a partial cross-sectional view of an image reading apparatus according to Embodiment 1. FIG. FIG. 4 is a schematic diagram illustrating a separation pad, a separation pad holding unit, and a separation roller according to the image reading apparatus of Embodiment 1. FIG. 8 is a partial cross-sectional view mainly showing a separation pad, a separation pad holding unit, a separation roller, a base, a pressing unit, and the like, taken along a line AA in FIG. 7. 1 is a perspective view of a detachable member according to an image reading apparatus of Embodiment 1. FIG. FIG. 3 is a partial perspective view mainly showing an attaching / detaching member, a pair of guides, and the like in an attached state, according to the image reading apparatus of Embodiment 1. FIG. 4 is a partial bottom view mainly showing a base, a separation pad, a separation pad holding unit, a detachable member in a mounted state, and the like according to the image reading apparatus of Embodiment 1. FIG. 12 is a partial cross-sectional view mainly showing a separation pad, a separation pad holding portion, a separation roller, a detachable member in a mounted state, etc., taken along the line BB in FIG. 11. It is CC cross section of FIG. 12, Comprising: It is a schematic diagram which shows the separation pad, the separation pad holding | maintenance part, the separation roller, and the attachment / detachment member in a mounting state. FIG. 6 is a schematic diagram illustrating a magnitude relationship between a path length from a separation nip position to a second nip position and a length in a conveyance direction of a predetermined sheet. FIG. 10 is a perspective view of an attaching / detaching member according to the image reading apparatus of Example 2. It is CC sectional drawing of FIG. 15, Comprising: It is a fragmentary sectional view which shows the attachment / detachment member in a mounting state, the predetermined sheet | seat hold | maintained at an attachment / detachment member, and a pair of guide.

  Embodiments 1 and 2 embodying the present invention will be described below with reference to the drawings.

Example 1
As shown in FIG. 1, the image reading apparatus 1 according to the first exemplary embodiment is an example of a specific aspect of the sheet conveying apparatus of the present invention. In FIG. 1, the side on which the operation panel 8P is provided is defined as the front side of the apparatus, and the side that comes to the left hand when facing the operation panel 8P is defined as the left side, and the front, rear, left, and right directions are displayed. . 2 are displayed in correspondence with the directions shown in FIG. 1. Hereinafter, each component provided in the image reading apparatus 1 will be described with reference to FIG.

<Overall configuration>
As shown in FIGS. 1 to 6, the image reading apparatus 1 includes a main body unit 8, an opening / closing unit 9, an image forming unit 5, a reading unit 3, and a conveying unit 4. The main body 8 is a flat substantially box-shaped body. As shown in FIG. 1, an operation panel 8 </ b> P that is a touch panel or the like is provided on the front surface of the main body 8.

  As shown in FIG. 4, the image forming unit 5 is accommodated in the lower portion of the main body 8. The image forming unit 5 forms an image on a sheet by an ink jet method or a laser method. The reading unit 3 is accommodated in the upper part in the main body 8. The reading unit 3 is used when reading an image of a document. The transport unit 4 is provided in the opening / closing unit 9. The transport unit 4 reads the image of the sheet SH while sequentially transporting the plurality of sheets SH supported by the support unit 6 along the transport path P1 shown in FIG. 4 or the transport path P2 shown in FIG. Used when reading from

  As shown in FIG. 4, a first platen glass 81 and a second platen glass 82 are disposed on the upper surface of the main body 8. A document support surface 81 </ b> A is formed by the upper surface of the first platen glass 81. The document support surface 81A supports the document from below when the reading unit 3 reads an image of the stationary document. Documents to be read include books, in addition to sheets such as paper and OHP sheets. The second platen glass 82 is located on the left side of the first platen glass 81 and extends in the longitudinal direction. A reading surface 82 </ b> A is formed by the upper surface of the second platen glass 82. The reading surface 82A guides the conveyed sheet SH from below when the reading unit 3 reads an image of the sheet SH conveyed one by one by the conveying unit 4.

  In this embodiment, an object whose image is read using the document support surface 81A is referred to as a document, and an object whose image is read while being conveyed by the conveying unit 4 is referred to as a sheet SH. The document and the sheet SH may be substantially the same.

  As shown in FIG. 1, the opening / closing part 9 is supported by a hinge (not shown) provided at the upper rear edge of the main body part 8 so as to be swingable around an opening / closing axis X9 extending in the left-right direction. In the closed state shown in FIGS. 1 to 4 and 6, the opening / closing unit 9 covers the document support surface 81 </ b> A from above. As shown by a two-dot chain line in FIG. 1, the opening / closing portion 9 swings around the opening / closing axis X9 so that the front end portion thereof is displaced upward and rearward, thereby exposing the document support surface 81A. It is displaced to. As a result, the user can support the document to be read on the document support surface 81A.

  As shown in FIG. 4, the reading unit 3 includes a reading sensor 3 </ b> A accommodated in the upper portion in the main body 8, a scanning mechanism (not shown), and a reading sensor 3 </ b> B accommodated in the opening / closing unit 9. . The reading sensors 3A and 3B are an example of the “reading unit” in the present invention.

  The reading sensor 3A reciprocates in the left-right direction below the document support surface 81A and the reading surface 82A in the main body 8 by the scanning mechanism. When reading an image of a document supported on the document support surface 81A, the reading sensor 3A reads the image while moving below the document support surface 81A. The position where the reading sensor 3A stops below the reading surface 82A is a fixed reading position. When reading an image while the sheet SH is conveyed by the conveying unit 4, the reading sensor 3A is stopped at the fixed reading position. As will be described later, the reading sensor 3B is disposed in the middle of the conveyance paths P1 and P2 in the opening / closing unit 9. As the reading sensors 3A and 3B, known image reading sensors such as CIS (Contact Image Sensor) and CCD (Charge Coupled Device) are employed.

  As shown in FIGS. 1 to 6, the image reading apparatus 1 includes a support portion 6, a base member 70, a guide member 50, and a pair of movable guides 61 and 62. The guide member 50 is an example of the “base” in the present invention. The movable guides 61 and 62 are an example of the “pair of guides” in the present invention.

  As shown in FIG. 1, an exterior cover 9 </ b> A is provided on the upper surface of the opening / closing part 9. The exterior cover 9A is divided into three parts: a first cover 75 located on the right side, a second cover 76 located in the center, and a third cover 77 located on the left side. In the closed state shown in FIG. 1, the second cover 76 constitutes the upper exterior of the opening / closing part 9 together with the first cover 75 and the third cover 77. The second cover 76 constitutes a part of the support portion 6 by being deployed as shown in FIGS. 2 and 3. The support unit 6 supports the sheet SH conveyed from the lower side by the conveyance unit 4 in a predetermined conveyance direction. The sheet SH includes paper and an OHP sheet.

  As shown in FIGS. 2 to 4 and 6, the base member 70 constitutes the lower part of the opening / closing part 9. The base member 70 extends in a substantially flat plate shape so as to cover the document support surface 81A and the reading surface 82A when the opening / closing portion 9 is in the closed position.

  A mounting surface 70 </ b> A is formed on the upper surface side of the base member 70. 70 A of mounting surfaces are connected to the left end edge of the 2nd cover 76 of the expand | deployed state, and are extended substantially horizontal toward the left side. The placement surface 70A supports the sheet SH placed on the second cover 76 from below. The mounting surface 70 </ b> A also constitutes a part of the support portion 6 together with the second cover 76 in the unfolded state.

  As shown in FIGS. 2 to 4, the pair of movable guides 61 and 62 are provided on the mounting surface 70 </ b> A of the base member 70. The movable guides 61 and 62 project vertically upward while facing each other with a gap W in the front-rear direction, and then bent in a direction approaching each other in the front-rear direction. The movable guides 61 and 62 further have extension portions 61A and 62A extending in a direction approaching the front-rear direction. The extending portions 61A and 62A and the placement surface 70A have a predetermined interval in the vertical direction. The front-rear direction in which the movable guides 61 and 62 face each other is orthogonal to the conveyance direction when the sheet SH is conveyed along the conveyance paths P1 and P2. The front-rear direction is an example of the “width direction” in the present invention.

  As shown in FIGS. 2 and 3, a guide rail 68 extending in the front-rear direction is formed on the mounting surface 70 </ b> A of the base member 70. The movable guides 61 and 62 are supported by the base member 70 so as to be slidable in the front-rear direction along the guide rail 68. As shown in FIG. 4, the movable guides 61 and 62 are connected by a rack and pinion mechanism 69 disposed on the back side of the placement surface 70A.

  As shown in FIG. 2, when the rack and pinion mechanism 69 is displaced in the front-rear direction so that one of the movable guides 61 and 62 approaches the other, the displacement is transmitted to the other of the movable guides 61 and 62 to move. The other of the guides 61 and 62 is displaced in the front-rear direction so as to approach one. Further, as shown in FIG. 3, when the rack and pinion mechanism 69 is displaced in the front-rear direction so that one of the movable guides 61 and 62 is separated from the other, the displacement is transmitted to the other of the movable guides 61 and 62. The other of the movable guides 61 and 62 is displaced in the front-rear direction so as to be separated from the other. Here, the distance from the intermediate position in the front-rear direction of the placement surface 70A to the guide 61 is configured to be always equal to the distance from the intermediate position in the front-rear direction of the placement surface 70A to the guide 62.

  Thus, the pair of movable guides 61 and 62 moves in the front-rear direction to increase or decrease the interval W, thereby positioning the sheets SH supported by the support unit 6 in the front-rear direction with reference to the center. To do.

  As shown in FIG. 2, the pair of movable guides 61 and 62 are spaced apart by a distance W = W1 when positioning a small-sized sheet SH (SH1) such as a business card, for example. On the other hand, as shown in FIG. 3, the pair of movable guides 61 and 62 are spaced apart by an interval W = W2 (> W1) when positioning a large sheet SH (SH2) such as an A4 sheet, for example. . Note that the business card as the small-sized sheet SH (SH1) is an example, and when the card, postcard, A6 size or the like is positioned by the movable guides 61 and 62, the interval W is close to W1. . Similarly, the A4 size sheet as the large size sheet SH (SH2) is an example, and when the letter size, the A3 size (short direction), or the like is positioned by the movable guides 61 and 62, the interval W Is a position close to W2.

  As shown in FIG. 4, the base member 70 is formed with an inclined surface 70 </ b> B, an opening 70 </ b> C, a pressing member support portion 70 </ b> F, and a housing portion 70 </ b> H. The inclined surface 70B is located on the left side of the mounting surface 70A, continues to the mounting surface 70A, and is inclined downward toward the left side. The opening 70C is cut out in a rectangular shape elongated in the front-rear direction on the left side of the inclined surface 70B. The pressing member support portion 70F is positioned on the upper side of the opening portion 70C and extends in the front-rear direction, and straddles the opening portion 70C in the front-rear direction. The accommodating portion 70H is located on the left side of the pressing member support portion 70F and is recessed upward.

  A pressing member 39A is disposed below the pressing member support portion 70F. The pressing member 39A is supported by the pressing member support portion 70F so as to be displaceable in the vertical direction. The pressing member 39A is biased by a compression coil spring and faces the reading surface 82A from above.

  The reading sensor 3B is accommodated in the accommodating portion 70H. A third platen glass 83 is disposed below the reading sensor 3B. The third platen glass 83 closes the accommodating portion 70H. A reading surface 83 </ b> A is formed by the lower surface of the third platen glass 83. The reading surface 83A guides the conveyed sheet SH from above when the reading unit 3 reads an image of the sheet SH conveyed one by one by the conveying unit 4.

  A pressing member support 8 </ b> F is formed on the upper surface of the main body 8 at a position on the left side of the second platen glass 82. The pressing member support portion 8F is positioned below the third platen glass 83 in a state where the opening / closing portion 9 is closed.

  A pressing member 39B is disposed above the pressing member support portion 8F. The pressing member 39B is supported by the pressing member support portion 8F so as to be displaceable in the vertical direction. The pressing member 39B is urged by the compression coil spring and faces the reading surface 83A from below.

  As shown in FIGS. 4 and 6, the base member 70 supports the switching member 78 at a position on the left side of the housing portion 70H so as to be displaceable. A surface facing the right side of the switching member 78 is a lower curved guide surface 78D. As shown in FIG. 4, the lower curved guide surface 78 </ b> D is opposed to the outer peripheral surface of the second conveyance roller 44 constituting the conveyance unit 4 with a predetermined interval, and is curved while being curved toward the left side. Inclined.

  The switching member 78 is displaced from the position shown in FIG. 4 to the position shown in FIG. 6 in conjunction with the opening of the left side cover 79 of the opening / closing portion 9 from the closed state shown in FIG. 4 as shown in FIG. To do. When the switching member 78 is displaced to the position shown in FIG. 6, the lower end side of the lower curved guide surface 78 </ b> D moves to the right side from the position shown in FIG. 4, and comes into contact with the outer peripheral surface of the second transport roller 44 constituting the transport unit 4. It is held at the position just before.

  As shown in FIGS. 3 to 6, the guide member 50 is positioned above the left side portion of the mounting surface 70 </ b> A, the inclined surface 70 </ b> B, the opening 70 </ b> C, the pressing member support portion 70 </ b> F, and the housing portion 70 </ b> H. It extends in the left-right direction. The guide member 50 is assembled on the upper side of the base member 70 in a state where the front end edge side and the rear end edge side are fixed to the base member 70 and straddle the mounting surface 70A in the front-rear direction. An upper surface extending substantially horizontally of the guide member 50 is a guide surface 50G.

  As shown in FIGS. 3 and 4, the guide surface 50G is adjacent to the extending portions 61A and 62A of the movable guides 61 and 62 from the left side. The extending portions 61 </ b> A and 62 </ b> A of the movable guides 61 and 62 and the guide surface 50 </ b> G constitute the discharge portion 7. The discharge part 7 is located above the support part 6. The sheet SH that has been transported by the transport unit 4 and whose image has been read by the reading sensors 3A and 3B is discharged to the discharge unit 7.

  As shown in FIGS. 4 and 6, the third cover 77 covers the guide surface 50 </ b> G and the second transport roller 44 constituting the transport unit 4 from the upper side. The lower surface of the third cover 77 is a cover side guide surface 77G and an upper curved guide surface 77D. The cover side guide surface 77G faces the guide surface 50G from above. The upper curved guide surface 77D is formed in a range facing the second transport roller 44 of the third cover 77. The upper curved guide surface 77D is connected to the lower curved guide surface 78D in a state where the switching member 78 is at the position shown in FIG. 4, and is inclined upward while being curved toward the right side.

  The third cover 77 rotatably supports the discharge pinch roller 44R. The discharge pinch roller 44 </ b> R constitutes the transport unit 4.

  As shown in FIG. 4, when the left side cover 79 of the opening / closing part 9 is closed, the conveyance path P <b> 1 shown in FIG. 4 is defined by the base member 70, the guide member 50, the switching member 78, and the third cover 77. .

  The conveyance path P1 includes a portion that is inclined downward from the placement surface 70A (support 6) toward the left side along the inclined surface 70B and passes above the reading surface 82A of the second platen glass 82. At this time, the lower surface of the pressing member 39A defines, from the upper side, a portion passing through the upper side of the reading surface 82A in the transport path P1.

  The transport path P1 includes a portion that passes below the reading surface 83A of the third platen glass 83. At this time, the upper surface of the pressing member 39B defines a portion of the transport path P1 that passes below the reading surface 83A from the lower side.

  The conveyance path P1 includes a portion that makes a U-turn upward along the lower curved guide surface 78D and the upper curved guide surface 77D and changes the conveyance direction of the sheet SH from left to right.

  The conveyance path P1 is guided by the guide surface 50G of the guide member 50, proceeds to the right, and includes a portion reaching the upper side of the extending portions 61A and 62A of the movable guides 61 and 62. At this time, the cover side guide surface 77G faces the guide surface 50G across the transport path P1, and defines the transport path P1 from above. The cover side guide surface 77G guides the sheet SH toward the upper side of the extending portions 61A and 62A of the movable guides 61 and 62 while being in contact with the conveyed sheet SH together with the guide surface 50G.

  Thus, the conveyance path P1 guides the sheet SH supported by the support unit 6 to the reading sensors 3A and 3B and further guides the sheet SH to the discharge unit 7. The conveyance path P1 is mainly a large size such as A4 size or letter size, and is applied to conveyance of a thin sheet SH.

  As shown in FIG. 6, when the left side cover 79 of the opening / closing part 9 is opened, the base member 70, the switching member 78, and the left side cover 79 define the conveyance path P2 shown in FIG. The conveyance path P2 is the same as the conveyance path P1 until just before the switching member 78. In the conveyance path P2, the switching member 78 displaced to the position shown in FIG. 6 prohibits the sheet SH from moving upward and guides it to the left.

  Thus, the conveyance path P2 guides the sheet SH supported by the support portion 6 to the reading sensors 3A and 3B, and further guides the sheet SH to the surface facing the upper side of the left side cover 79 in the opened state. . The conveyance path P2 is applied to conveyance of a small-sized sheet SH such as a postcard or a business card, or a sheet SH that is difficult to bend even if it is a large size.

  As shown in FIGS. 4, 5, 7, and 8, the transport unit 4 includes a feeding roller 41, a separation roller 42, a separation pad 20, a separation pad holding unit 25, and a torsion coil spring 29. . The torsion coil spring 29 is an example of the “pressing means” in the present invention.

  As shown in FIG. 4, the feeding roller 41 and the separation roller 42 are rotatably supported by the base member 70, and the upper portion of the base roller 70 is exposed on the left side portion of the mounting surface 70 </ b> A. The separation roller 42 is positioned downstream of the feeding roller 41 in the transport paths P1 and P2, that is, on the left side with respect to the feeding roller 41, and is rotatable around a first axis X1 parallel to the front-rear direction. Yes. The feeding roller 41 and the separation roller 42 are driven by a driving source (not shown) and rotate synchronously. The feeding roller 41 sends the sheet SH supported by the support unit 6 toward the downstream side in the transport direction, that is, leftward. The separation roller 42 conveys the sheet SH supported by the support unit 6 together with the feeding roller 41 to the left.

  As shown in FIGS. 4, 5, 7, and 8, the separation pad 20 is a small rectangular piece made of a friction member such as rubber, elastomer, or sponge. The lower surface of the separation pad 20 facing the separation roller 42 comes into contact with the sheet SH fed to the feeding roller 41 from the upper side, and gives a frictional force to the sheet SH.

  The separation pad holding part 25 is a resin member formed in a substantially plate shape. A shaft support portion 50 </ b> H is integrally formed on the lower surface of the guide member 50. The right end portion of the separation pad holding portion 25 is supported by the shaft support portion 50H so as to be swingable around the second axis X2 parallel to the width direction. The second axis X2 extends in the front-rear direction at a position above and on the right side of the first axis X1. The separation pad holding part 25 extends to the left side and the lower side above the separation roller 42 so as to be separated from the second axis X2.

  The surface of the separation pad 20 facing away from the separation roller 42 is affixed to the lower surface of the separation pad holding unit 25 on the left end side, and faces the separation roller 42 from above. As the separation pad holding part 25 swings around the second axis X2, the separation pad 20 held by the separation pad holding part 25 approaches and separates from the separation roller.

  Spring receiving portions 50 </ b> J and 50 </ b> K are formed on the lower surface of the guide member 50. The torsion coil spring 29 is elastically deformed, the coiled portion is locked to the spring receiving portion 50J, one end side is locked to the spring receiving portion 50K, and the other end side is the left end portion of the separation pad 20 It is locked to the upper surface of the side. Thereby, the torsion coil spring 29 presses the separation pad holding part 25 toward the separation roller 42.

  As shown in FIG. 7, the pressing load with which the torsion coil spring 29 presses the separation pad holding part 25 is defined as Fs1. A pressing load acting on the separation pad 20 is defined as F1. The state shown in FIG. 7 is a state in which a first sheet holder 100 described later is removed. In this state, the pressing load Fs1 that the torsion coil spring 29 presses the separation pad holding part 25 acts on the separation pad 20 as it is, and the separation pad 20 is pressed against the separation roller 42 by the pressing load F1 (= Fs1).

  The separation pad 20 separates the sheets SH one by one when a plurality of sheets SH fed to the feeding roller 41 overlap with each other in cooperation with the separation roller 42. More specifically, when the separation pad 20 is pressed against the separation roller 42 by the torsion coil spring 29, a braking force generated between the separation roller 42 and the separation pad 20 acts on the sheet SH. As a result, when a plurality of sheets SH are about to be conveyed in a state of being overlapped by the separation roller 42, the braking force acts on the sheets other than the sheet in contact with the separation roller 42 among the sheets SH, and the sheet SH SH is separated one by one.

  As shown in FIGS. 4 and 6, the transport unit 4 includes a first transport roller 43, a first pinch roller 43P, a second transport roller 44, a second pinch roller 44P, a third pinch roller 44Q, and a discharge pinch roller 44R. Have. The first transport roller 43 and the first pinch roller 43P are an example of the “first transport roller pair” in the present invention. The second transport roller 44 and the second pinch roller 44P are an example of the “second transport roller pair” in the present invention.

  The first conveying roller 43 is rotatably supported by the guide member 50 at a position facing the inclined surface 70B from above. The first pinch roller 43P is rotatably supported by the base member 70, and the upper portion thereof is exposed from the inclined surface 70B. The first pinch roller 43P is pressed toward the first transport roller 43.

  The second conveyance roller 44 is rotatably supported by the base member 70 at a position on the right side of the lower curved guide surface 78D and the upper curved guide surface 77D. The lower left portion of the outer peripheral surface of the second transport roller 44 is opposed to the lower curved guide surface 78D from the upper side and the right side with the curved portion of the transport path P1 interposed therebetween. The upper left portion of the outer peripheral surface of the second transport roller 44 faces the upper curved guide surface 77D of the third cover 77 from the lower side and the right side with the curved portion of the transport path P1 interposed therebetween.

  The second pinch roller 44P and the third pinch roller 44Q are positioned below the outer peripheral surface of the second transport roller 44 and are rotatably supported by the base member 70. The third pinch roller 44Q is located on the left side of the second pinch roller 44P. The second pinch roller 44P and the third pinch roller 44Q are pressed toward the second transport roller 44. The discharge pinch roller 44R is rotatably supported by the third cover 77 and is pressed toward the second transport roller 44R.

  The first conveyance roller 43 and the first pinch roller 43P convey the sheet SH sent to the conveyance path P1 by the feeding roller 41 and the separation roller 42 toward the opening 70C and the second conveyance roller 44. As a result, the sheet SH passes between the reading surface 82A of the second platen glass 82 and the lower surface of the pressing member 39A, that is, the upper side of the reading sensor 3A. Further, the sheet SH passes between the reading surface 83A of the third platen glass 83 and the upper surface of the pressing member 39B, that is, the lower side of the reading sensor 3B.

  As shown in FIG. 4, when the left side cover 79 of the opening / closing part 9 is closed, the second conveying roller 44, the second pinch roller 44P, the third pinch roller 44Q, and the discharge pinch roller 44R are located on the upper side of the reading sensor 3A. The sheet SH that has passed under the reading sensor 3B is conveyed so as to make a U-turn upward, that is, along the curved portion of the conveyance path P1. At this time, the lower curved guide surface 78D and the upper curved guide surface 77D abut against the sheet SH from the outside of the curve with respect to the sheet SH passing through the curved portion of the conveyance path P1, and the sheet SH is guided while being curved. . Then, the second transport roller 44 and the discharge pinch roller 44R transport the sheet SH to the right and discharge it to the discharge unit 7. As a result, the sheet SH is stacked on the upper side of the guide surface 50G as the discharge portion 7 and the extending portions 61A and 62A of the movable guides 61 and 62. That is, the guide surface 50G serves as both guidance of the sheet SH and stacking of the sheets SH.

  As shown in FIG. 6, in a state where the left side cover 79 of the opening / closing unit 9 is opened and the switching member 78 prohibits the sheet SH from moving upward, the second conveying roller 44, the second pinch roller 44P, and the third The pinch roller 44Q conveys the sheet SH that has passed the upper side of the reading sensor 3A and the lower side of the reading sensor 3B leftward, that is, along the conveyance path P2. As a result, the sheet SH is discharged onto the surface facing the upper side of the left side cover 79 in the opened state.

<Image reading operation>
In the image reading apparatus 1, when reading an image of a document supported on the document support surface 81A, a scanning mechanism (not shown) operates in the reading unit 3, and the reading sensor 3A is moved from the lower side of the left edge of the document support surface 81A to the right end. Move left and right between the edges. As a result, the reading sensor 3A reads the image of the document supported on the document support surface 81A. Thereafter, the scanning mechanism (not shown) moves the reading sensor 3A that has finished reading from the right end side to the left end side in the reading unit 3 to return to the original position.

  In the image reading apparatus 1, when reading images of a plurality of sheets SH supported by the second cover 76 and the placement surface 70 </ b> A as the support unit 6, a scanning mechanism (not shown) operates in the reading unit 3. Then, the reading sensor 3A is stopped at a fixed reading position below the reading surface 82A. When the transport unit 4 sequentially transports the sheet SH placed on the second cover 76 and the placement surface 70A along the transport path P1 shown in FIG. 4 or the transport path P2 shown in FIG. 6, the sheet SH becomes the reading surface. Since the sheet passes through the upper side of the reading sensor 3A at the fixed reading position while being in contact with 82A, and further passes under the reading sensor 3B while being in contact with the reading surface 83A, the reading sensors 3A and 3B are the sheets through which they pass. Read images on both sides of SH. The transport unit 4 transports the sheet SH on which an image has been read, and discharges the sheet SH onto the discharge unit 7 or the left side cover 79 in an opened state.

<Specific configuration of first sheet holder>
As shown in FIGS. 9 to 13, the image reading apparatus 1 further includes a first sheet holder 100. The first sheet holder 100 is an example of the “detachable member” in the present invention.

  As shown in FIG. 10, the first sheet holder 100 is mounted on the mounting surface 70A constituting the conveyance unit 4, and is removed from the mounting surface 70A as shown in FIGS. It is possible to change to a detached state. 11 to 13 show the first sheet holder 100 in the mounted state. The front-rear direction and the left-right direction shown in FIG. 9 are also based on the first sheet holder 100 in the mounted state.

  The first sheet holder 100 can be selectively placed in a mounted state by a user operation when a small-sized sheet SH1 such as a business card is transported by the transport unit 4. That is, the user mounts the sheet SH <b> 1 on the placement surface 70 </ b> A that is a part of the transport unit 40 with the first sheet holder 100 holding the sheet SH <b> 1. Alternatively, after the first sheet holder 100 is mounted on the placement surface 70A, the sheet SH1 is held by the first sheet holder 100. Here, the small-sized sheet SH1 such as a business card is an example of the “predetermined sheet” in the present invention. The sheet SH1 includes a sheet slightly larger than the business card, a sheet slightly smaller than the business card, and the like. As shown in FIG. 2, the user can also transport the small-sized sheet SH1 such as a business card by the transport unit 4 while the first sheet holder 100 is in the detached state.

  As shown in FIG. 9, the first sheet holder 100 includes a sheet holding part 110 and an action part 120.

  The sheet holding part 110 has a flat plate part 115 and side walls 111, 112, 113. The flat plate portion 115 is a plate-like body that has a substantially rectangular shape corresponding to the outline of a small-sized sheet SH1 such as a business card and extends in the front-rear direction and the left-right direction.

  The side wall 111 is connected to the front end edge of the flat plate portion 115, protrudes upward, and extends in the left-right direction. The side wall 112 is connected to the rear end edge of the flat plate portion 115, protrudes upward, and extends in the left-right direction. The side wall 113 is connected to the right end edge of the flat plate portion 115, protrudes upward, and extends in the front-rear direction. The front end portion of the side wall 113 is connected to the right end portion of the side wall 111. The rear end portion of the side wall 113 is connected to the right end portion of the side wall 112.

  An inner width W110 in the front-rear direction between the side wall 111 and the side wall 112 is set to a size that allows a small-sized sheet SH1 such as a business card to fit in the front-rear direction. As shown in FIG. 10, with the sheet holding unit 110 holding a plurality of sheets SH1, the first sheet holder 100 is placed on the placement surface 70A, and the pair of movable guides 61 and 62 are indicated by solid lines. The movable guides 61 and 62 sandwich the side walls 111 and 112 of the first sheet holder 100 from outside in the front-rear direction by moving from the position to the position indicated by the two-dot chain line. Accordingly, the first sheet holder 100 in the mounted state is positioned in the front-rear direction on the placement surface 70A, and the sheet SH1 held by the sheet holding unit 110 is also indirectly positioned in the front-rear direction.

  As shown in FIG. 9, the sheet holding unit 110 has a notch 119. The notch 119 is notched so that the left side portion of the flat plate portion 115 is recessed rightward. As shown in FIG. 11, when the first sheet holder 100 is in the mounted state, the notch 119 extends to a position corresponding to the feeding roller 41, the separation roller 42, and the separation pad 20. That is, the position and size of the notch 119 are set so that the first sheet holder 100 in the mounted state does not interfere with the feeding roller 41, the separation roller, and the separation pad 20.

  The action part 120 has a pair of contact parts 121 and 122. The front contact portion 121 is connected to the left end portion of the side wall 111 of the first sheet holder 100. The front-side contact portion 121 has a surface that is stepped backward from a portion that is at the same height as the upper end of the side wall 111, and a small protrusion 121A protrudes backward at the rear end of the step-down surface. Is formed. The rear contact portion 122 is connected to the left end portion of the side wall 112 of the first sheet holder 100. The rear contact portion 122 has a surface that is stepped forward one step from a portion that is at the same height as the upper end of the side wall 112, and a small protrusion 122A protrudes forward at the front end of the stepped surface. Is formed.

  As illustrated in FIGS. 12 and 13, the lower surfaces 121 </ b> C and 122 </ b> C of the contact portions 121 and 122 are located above the upper surface of the flat plate portion 115 of the sheet holding unit 110. The plurality of sheets SH <b> 1 held by the sheet holding unit 110 is pressed from above by the lower surfaces 121 </ b> C and 122 </ b> C of the contact portions 121 and 122.

  A protrusion 131 is formed on the front contact portion 121. A protrusion 132 is formed on the rear contact portion 122. The front protruding portion 131 protrudes upward from a portion at the same height as the upper end of the side wall 111 in the contact portion 121, and further protrudes to the left in a substantially prismatic shape. The rear protruding portion 132 protrudes upward from a portion at the same height as the upper end of the side wall 112 in the contact portion 122, and further protrudes to the left in a substantially prismatic shape. The protrusions 131 and 132 are positioned at the downstream end in the transport direction of the first sheet holder 100 in the mounted state.

  As shown in FIGS. 5 and 11, the image reading apparatus 1 further includes a positioning unit 59. The positioning unit 59 includes contacted portions 51 and 52 provided on the lower surface of the guide member 50 constituting the transport unit 4. The abutted portions 51 and 52 are a part of the surface facing the right side of the rib 50R formed on the lower surface of the guide member 50 and extending in the left-right direction. The front contacted part 51 is located in front of the separation pad 20. The rear contacted portion 52 is located on the rear side of the separation pad 20.

  As shown in FIG. 11, when the first sheet holder 100 is in the mounted state, the action part 120 extends to the lower surface side of the guide member 50 and protrudes at a position adjacent to the separation pad 20 from the outside in the front-rear direction. The parts 131 and 132 are brought into contact with the contacted parts 51 and 52. Thus, the first sheet holder 100 in the mounted state is positioned with respect to the transport unit 4 by the positioning unit 59. Specifically, the first sheet holder 100 is positioned with respect to the guide member 50 constituting the transport unit 4 and is also indirectly positioned with respect to the separation pad 20, the separation pad holding unit 25, the separation roller 42, and the like. .

  As shown in FIGS. 11 to 13, when the first sheet holder 100 is in the mounted state, the action portion 120 extends to the lower surface side of the guide member 50 and is adjacent to the separation pad 20 from outside in the front-rear direction. Positioned with. In this state, the protrusion 121A of the front contact portion 121 contacts the front end edge side of the separation pad holding portion 25 from below, and the protrusion 122A of the rear contact portion 122 faces the rear end edge side of the separation pad holding portion 25. Contact from below. Thereby, the action part 120 presses the separation pad holding part 25 away from the separation roller 42, that is, upward.

  As shown in FIG. 12, the pressing load that the action part 120 presses the separation pad holding part 25 upward by the projection 121A of the front contact part 121 is defined as Fr1. Further, the pressing load that the action part 120 presses the separation pad holding part 25 upward by the projection 122A of the rear contact part 122 is defined as Fr2. As described above, the protrusion 121A and the protrusion 122A are configured to press the front end and the rear end of the separation pad holding portion 25 upward under substantially the same conditions. Thereby, the pressing load Fr1 and the pressing load Fr2 become substantially equal, and the separation pad holding part 25 is pressed evenly in the front-rear direction.

  Thereby, the pressing load F1 acting on the separation pad 20 is changed from the pressing load Fs1 in which the torsion coil spring 29 presses the separation pad holding part 25 to the pressing load in which the protrusions 121A and 122A press the separation pad holding part 25 upward. A value obtained by subtracting Fr1 and Fr2 (F1 = Fs1-Fr1-Fr2). Thus, in the mounted state, the first sheet holder 100 indirectly presses the separation pad 20 upward by the action portion 120, and reduces the pressing load F1 acting on the separation pad 20.

  As shown in FIG. 14, the position where the separation roller 42 and the separation pad 20 nip the sheet SH is defined as a separation nip position N1. A position where the second conveying roller 44 and the second pinch roller 44P nip the sheet SH is defined as a second nip position N2. A path length L1 from the separation nip position N1 to the second nip position N2 is set to be longer than a length L2 in the conveyance direction of a small-sized sheet SH1 such as a business card.

<Effect>
In the image reading apparatus 1 according to the first embodiment, as illustrated in FIG. 7, when the first sheet holder 100 is in the detached state, the torsion coil spring 29 is used as the pressing load F <b> 1 acting on the separation pad 20. It is equal to the pressing load Fs1 for pressing 25. On the other hand, as shown in FIG. 12, when the first sheet holder 100 is in the mounted state, the first sheet holder 100 reduces the pressing load F1 acting on the separation pad 20 (F1 = Fs1-Fr1-Fr2). .

  In the image reading apparatus 1, for example, when the user uses a small-sized sheet SH 1 such as a business card as the sheet SH, the first sheet holder 100 is put into a mounted state. Thereby, the action part 120 of the first sheet holder 100 reduces the pressing load F1 acting on the separation pad 20 from (F1 = Fr1) to (F1 = Fs1-Fr1-Fr2). An appropriate braking force acts on the sheet SH1. As a result, the conveyance speed of the sheet SH1 that is separated and conveyed by the separation roller 42 is less likely to fluctuate. On the other hand, when the user uses a wide sheet, a thin sheet, a slippery sheet, or the like as the sheet SH, the first sheet holder 100 is set in the detached state. The action portion 120 of the first sheet holder 100 increases the pressing load F1 acting on the separation pad 20 from (F1 = Fs1−Fr1−Fr2) to (F1 = Fr1), so that an appropriate braking force is applied to the sheets SH. Works. As a result, in the image reading apparatus 1, it is difficult for sheets other than the sheet in contact with the separation roller 42 to slide with respect to the separation pad 20, and it is difficult for SH to be fed.

  Therefore, in the image reading apparatus 1 according to the first embodiment, the sheet SH can be satisfactorily separated and conveyed regardless of the type of the sheet SH.

  Further, a small sheet SH1 such as a business card is generally thick. In this respect, in the image reading apparatus 1, the first sheet holder 100 is mounted when using a small sheet SH1 such as a business card, and the pressing load F1 acting on the separation pad 20 is small. The size is reduced to a size suitable for the sheet SH1. Thereby, in this image reading apparatus 1, it becomes difficult for excessive braking force to act on a small-sized sheet SH1 such as a business card, and fluctuations in the business card conveyance speed can be suppressed.

  Further, in the image reading apparatus 1, as shown in FIG. 12, the first sheet holder 100 is configured to press the separation pad 20 away from the separation roller 42, that is, upward in the mounted state. The holder 100 can be simplified.

  In the image reading apparatus 1, as shown in FIGS. 10 to 13, the first sheet holder 100 has a function of holding a small-sized sheet SH <b> 1 such as a business card by the sheet holding unit 110 and an action unit. Since the function of reducing the pressing load F1 acting on the separation pad 20 by 120 is exhibited, convenience is improved.

  Furthermore, in this image reading apparatus 1, as shown in FIGS. 11 to 13, the action unit 120 abuts against the separation pad holding unit 25, so that the torsion coil spring 29 presses the separation pad holding unit 25. Since a part of the load Fs1 is shared, the pressing load F1 acting on the separation pad 20 can be reduced by that amount.

  In the image reading apparatus 1, as shown in FIGS. 11 and 12, the pair of contact portions 121 and 122 are in contact with the separation pad holding portion 25 evenly in the front-rear direction. It is difficult to tilt in the direction. For this reason, in the image reading apparatus 1, when the pressing load F1 acting on the separation pad 20 is reduced, it is possible to prevent the degree of reduction from becoming uneven in the front-rear direction.

  Further, in the image reading apparatus 1, as shown in FIG. 10, the first sheet holder 100 is positioned in the front-rear direction by the pair of movable guides 61 and 62 when in the mounted state. Thereby, in this image reading apparatus 1, since it becomes unnecessary to make the structure which positions the 1st sheet holder 100 in the front-back direction in the 1st sheet holder 100, the 1st sheet holder 100 can be simplified.

  In the image reading apparatus 1, as shown in FIG. 14, the path length L1 from the separation nip position N1 to the second nip position N2 is longer than the length L2 in the conveyance direction of a small-sized sheet SH1 such as a business card. It is set long. For this reason, a small-sized sheet SH1 such as a business card is conveyed to the downstream side in the conveyance direction from the state of being nipped by the separation roller 42 and the separation pad 20 and nipped by the first conveyance roller 43 and the first pinch roller 43P. Thus, when the nipping is not performed between the separation roller 42 and the separation pad 20, only the first conveying roller 43 and the first pinch roller 43P are nipped. Thereafter, a small-sized sheet SH1 such as a business card is conveyed downstream in the conveying direction, nipped by the first conveying roller 43 and the first pinch roller 43P, and nipped by the second conveying roller 44 and the second pinch roller 44P. It will be in a state to be. When the state in which the small-sized sheet SH1 such as a business card is nipped changes in this way, if an excessive braking force acts on the small-sized sheet SH1 such as a business card, the small-sized sheet SH1 such as a business card The conveyance speed is more likely to fluctuate. In this regard, in the image reading apparatus 1, the pressing load F1 acting on the separation pad 20 is reduced by putting the first sheet holder 100 in the mounted state, and an excessive braking force is applied to a small-sized sheet SH1 such as a business card. Therefore, it is possible to reliably suppress fluctuations in the conveyance speed of a small-sized sheet SH1 such as a business card.

  Further, in the image reading apparatus 1, as shown in FIG. 11, the first sheet holder 100 is separated from the separation roller 42 and the separation pad 20 by the notch 119 cut out in the sheet holding unit 110 of the first sheet holder 100. The function of holding a small sheet SH1 such as a business card and the function of reducing the pressing load F1 acting on the separation pad 20 can be exhibited while avoiding the interference.

  Further, in the image reading apparatus 1, the first sheet holder 100 avoids interference with the feeding roller 41 by the cutout portion 11 extended to a position corresponding to the feeding roller 41, and small business cards and the like. The function of holding the size sheet SH1 and the function of reducing the pressing load F1 acting on the separation pad 20 can be exhibited.

  Further, in the image reading apparatus 1, as shown in FIGS. 5 and 11, the first sheet holder 100 can be accurately positioned in the transport direction with respect to the transport unit 4 by the positioning unit 59. When the is in the mounted state, the pressing load F1 acting on the separation pad 20 can be accurately reduced to a desired magnitude, and that state can be maintained.

  In the image reading apparatus 1, the positioning unit 59 includes the contacted parts 51 and 52. Then, in the vicinity of the separation pad 20, the protruding portions 131 and 132 of the first sheet holder 100 in the mounted state are brought into contact with the contacted portions 51 and 52. Thereby, in this image reading apparatus 1, the pressing load F1 which acts on the separation pad 20 can be reduced to a desired magnitude with higher accuracy and the state can be maintained.

  Further, in this image reading apparatus 1, as shown in FIGS. 4 and 6, the first sheet holder 100 is appropriately detached and conveyed by the separation roller 42 and the separation pad 20 one by one as appropriate. Since the reading sensors 3A and 3B read the image of the sheet SH to be read, the reading quality of the reading sensors 3A and 3B is stabilized.

(Example 2)
In the image reading apparatus according to the second embodiment, a second sheet holder 200 shown in FIGS. 15 and 16 is employed instead of the first sheet holder 100 in the image reading apparatus 1 according to the first embodiment. Other configurations of the second embodiment are the same as those 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.

  The second sheet holder 200 is also an example of the “detachable member” in the present invention. The second sheet holder 200 includes a sheet holding part 210 and an action part 220.

  The sheet holding part 210 has a flat plate part 215 and side walls 211 and 212. The flat plate portion 215 is a plate-like body that has a substantially rectangular shape corresponding to the outline of a small-sized sheet SH1 such as a business card and extends in the front-rear direction and the left-right direction. The sheet holding unit 210 holds a plurality of sheets SH1 in a state of covering from above.

  The side wall 211 is connected to the front end edge of the flat plate portion 215, protrudes upward, and extends in the left-right direction. The side wall 212 is connected to the rear end edge of the flat plate portion 215, protrudes upward, and extends in the left-right direction.

  An outer width W210 in the front-rear direction between the side wall 211 and the side wall 212 is set to a size such that a small-sized sheet SH1 such as a business card protrudes in the front-rear direction. As shown in FIG. 16, in a state where the second sheet holder 200 covers the plurality of sheets SH1 supported by the placement surface 70A from above, the second sheet holder 200 and the sheet SH1 are placed on the placement surface 70A. The sheet SH1 held by the second sheet holder 200 is sandwiched between the pair of movable guides 61 and 62 from the outside in the front-rear direction. Thus, the sheet SH1 held by the second sheet holder 200 in the mounted state is directly positioned in the front-rear direction by the movable guides 61 and 62 on the placement surface 70A.

  As shown in FIG. 15, the sheet holding unit 210 is formed with a notch 219. The cutout 219 is cut out so that the left side portion of the flat plate portion 215 is recessed rightward. Although not shown, when the second sheet holder 200 is in the mounted state, the notch 219 extends to a position corresponding to the feeding roller 41, the separation roller 42, and the separation pad 20. That is, the position and size of the notch 219 are set so that the second sheet holder 200 in the mounted state does not interfere with the feeding roller 41, the separation roller, and the separation pad 20.

  The action part 220 has a pair of contact parts 221 and 222. The front contact portion 221 is connected to the left end portion located on the front side of the notch portion 219 in the flat plate portion 215 of the second sheet holder 200. The front contact portion 221 has a surface that is stepped backward from a portion that is at the same height as the upper surface of the flat plate portion 215, and a small protrusion 221 </ b> A protrudes backward at the rear end of the stepped surface. It is formed as follows. The rear contact portion 222 is connected to the left end portion located on the rear side of the notch portion 219 in the flat plate portion 215 of the second sheet holder 200. The rear contact portion 222 has a surface that is stepped forward one step from a portion that is at the same height as the upper surface of the flat plate portion 215, and a small protrusion 222A projects forward at the front end of the stepped surface. It is formed as follows.

  A protrusion 231 is formed on the front contact portion 221. A protrusion 232 is formed on the rear contact portion 222. The front protruding portion 231 protrudes upward from a portion of the contact portion 221 that is at the same height as the upper surface of the flat plate portion 215, and further protrudes to the left in a substantially prismatic shape. The rear protruding portion 232 protrudes upward from a portion at the same height as the upper surface of the flat plate portion 215 in the contact portion 122, and further protrudes in a substantially prismatic shape to the left.

  The pair of contact portions 221 and 222 has the same configuration and operation as the pair of contact portions 121 and 122 in the action portion 120 of the first sheet holder 100 of the first embodiment. The same applies to the protrusions 221A and 222A and the protrusions 231 and 232 included in the pair of contact portions 221 and 222.

  Similarly to the image reading apparatus 1 of the first embodiment, the image reading apparatus of the second embodiment including the second sheet holder 200 can separate and transport the sheet SH well regardless of the type of the sheet SH. Can do.

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

  The configuration for changing the pressing load may be a configuration in which the pressing load when the detachable member is in the mounted state is increased with respect to the pressing load when the detachable member is in the detached state. Such a configuration can be realized, for example, by changing the working portion 120 of the first sheet holder 100 in the mounted state to press the separation pad holding portion 25 downward in the first embodiment.

  The detachable member may not include the sheet holding unit. The positioning part may be provided in the support part. Moreover, the positioning part may be provided in the support part and the conveyance part. For example, in Example 1, the sheet holding part 110 of the first sheet holder 100 is provided with a positioning convex part that protrudes downward, the concave part into which the positioning convex part is fitted is provided on the placement surface 70A, and these are used as the positioning part. Also good.

  The conveyance path along which the sheet is conveyed by the conveyance unit is not limited to the conveyance paths P1 and P2 of the first embodiment. For example, a transport path is adopted in which the discharge unit is positioned below the support unit, the sheet is transported from the support unit in a predetermined transport direction, and the sheet is transported so as to make a U-turn downward and reach the discharge unit. May be.

  The present invention can be used in, for example, an image reading apparatus, an image forming apparatus, a multifunction machine, and the like.

DESCRIPTION OF SYMBOLS 1 ... Sheet conveying apparatus (image reading apparatus), 3A, 3B ... Reading part (reading sensor)
, SH ... sheet (SH1 ... predetermined sheet (small size sheet such as a business card))
DESCRIPTION OF SYMBOLS 6 ... Support part, 4 ... Conveying part, X1 ... 1st axis, X2 ... 2nd axis 42 ... Separation roller, 20 ... Separation pad, 25 ... Separation pad holding | maintenance part 29 ... Pressing means (torsion coil spring), F1 ... Pressing load acting on the separation pad Fs1 ... Pressing load in which the pressing means (torsion coil spring) presses the separation pad holding portion 100, 200 ... Removable member (100 ... first sheet holder, 200 ... second sheet holder)
DESCRIPTION OF SYMBOLS 110,210 ... Sheet holding | maintenance part, 120,220 ... Action part 50 ... Base part (guide member), 121,122 ... A pair of contact part 61, 62 ... A pair of guide (movable guide)
43, 43P ... first conveying roller pair (43 ... first conveying roller, 43P ... first pinch roller)
44, 44P ... 2nd conveyance roller pair (44 ... 2nd conveyance roller, 44P ... 2nd pinch roller)
N1: Separation nip position, N2: Second nip position L1: Path length from the separation nip position to the second nip position L2: Length of a predetermined sheet in the conveyance direction, 119: Notch 41: Feed roller, 59 ... Positioning part, 51, 52 ... Contacted part 131, 132 ... End part (protrusion part) on the downstream side in the conveying direction of the detachable member in the mounted state

Claims (14)

A support for supporting the sheet;
A conveyance unit that conveys the sheet supported by the support unit in a predetermined conveyance direction, and the conveyance unit is a separation roller that is rotatable around a first axis parallel to a width direction orthogonal to the conveyance direction; ,
A separation pad that separates the sheets supported by the support portion one by one in cooperation with the separation roller;
Pressing means for pressing the separation pad toward the separation roller,
It further includes a detachable member that can be changed between a mounted state attached to the transport unit and a detached state detached from the transport unit, and changes a pressing load acting on the separation pad in the mounted state. A sheet conveying apparatus characterized by the above.   The sheet transporting apparatus according to claim 1, wherein the detachable member is placed in the mounted state when a predetermined sheet supported by the support unit is transported by the transport unit.   The sheet conveying apparatus according to claim 2, wherein the detachable member presses the separation pad in a direction away from the separation roller in the mounted state. The detachable member includes a sheet holding unit that holds the predetermined sheet on the support unit in the mounted state;
4. The sheet conveying apparatus according to claim 2, further comprising an action unit that is located on the conveying unit side and changes the pressing load in the mounted state. 5. The separation pad is held by a separation pad holder that can swing around a second axis parallel to the width direction,
The pressing means has one end side locked to a base part constituting a part of the transport unit and the other end side locked to the separation pad holding unit to press the separation pad toward the separation roller,
The sheet conveying apparatus according to claim 4, wherein the detachable member is configured to bring the action portion into contact with the separation pad holding portion in the mounted state. The action part has a pair of contact parts,
In the mounted state, the detachable member causes the abutting portions to abut on the separation pad holding portion at positions adjacent to the separation pad from the outside in the width direction, and the separation pad holding portion is separated from the separation roller. The sheet conveying apparatus according to claim 5, wherein the sheet conveying apparatus is configured to be pressed in a direction of separating. The separation pad is disposed to face the separation roller from above,
The sheet conveying apparatus according to claim 5, wherein the detachable member is configured to press the separation pad upward by the action portion in the mounted state. The sheet supported by the support portion is provided on the support portion, opposed to each other with an interval in the width direction, and at least one of the sheets moves in the width direction to enlarge or reduce the interval. A pair of guides for positioning in the width direction;
The predetermined sheet or the detachable member held by the sheet holding portion is positioned in the width direction by the pair of guides when the detachable member is in the mounted state. The sheet conveying apparatus according to claim 1. The conveyance unit is provided on the downstream side in the conveyance direction with respect to the separation roller and the separation pad, and conveys a sheet separated by the separation roller and the separation pad to the downstream side in the conveyance direction. Vs.
A second conveyance roller pair provided downstream of the first conveyance roller pair in the conveyance direction and conveying a sheet conveyed by the first conveyance roller pair to the downstream side of the conveyance direction;
From the separation nip position to the second nip position, a position where the separation roller and the separation pad nip a sheet is a separation nip position, and a position where the second conveying roller pair nips the sheet is a second nip position. 9. The sheet conveying apparatus according to claim 2, wherein the path length is set to be longer than a length of the predetermined sheet in the conveying direction. The detachable member includes a sheet holding portion that holds the predetermined sheet on the support portion in the mounted state,
The sheet holding portion has a substantially rectangular shape corresponding to an outline of the predetermined sheet, and a notch is cut out at a position corresponding to the separation roller and the separation pad in the mounted state. The sheet conveying apparatus according to any one of the above. The transport unit has a feeding roller that is provided upstream of the separation roller in the transport direction, and transports a sheet supported by the support unit toward the separation roller,
The sheet conveying device according to claim 10, wherein the notch is extended to a position corresponding to the feeding roller.   The positioning unit according to any one of claims 1 to 11, further comprising a positioning unit that is provided on at least one of the support unit and the transport unit and positions the detachable member in the mounted state with respect to the transport unit. Sheet conveying device.   The positioning unit includes a contacted part that is provided at a base part that constitutes a part of the transport unit, and that is in contact with a downstream end of the mounting member in the transport direction in the transport direction. 12. A sheet conveying apparatus according to 12.   14. The apparatus according to claim 1, further comprising a reading unit that is positioned downstream of the separation roller and the separation pad in the conveyance direction and reads an image of a sheet conveyed by the separation roller. Sheet conveying device.

Images