JP2017154895A - Image reading apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reading apparatus capable of inhibiting a reading quality from decreasing while implementing an improvement in productivity.SOLUTION: A conveyance section 4 includes a chute member 100 forming a guide surface 101 that extends to be able to abut on a first surface SH1 of a sheet SH and guides the sheet SH in a conveyance path P1. The chute member 100 includes a first chute member 110 forming a first guide surface 111, which defines an upper path PA1, in the guide surface 101, and a second chute member 120 forming a second guide surface 122, which defines one of a first slope portion PB11 and a second slope portion PB12, in the guide surface 101. The second chute member 120 includes a storage section 129 that is recessed toward the upper path PA1 from the second guide surface 122 and stores a first reading section 3A. The first chute member 110 forms a third guide surface 113, which defines the other of the first slope portion PB11 and the second slope portion PB12, in the guide surface 101.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an image reading apparatus.

  Patent Document 1 discloses an example of a conventional image reading apparatus. The image reading apparatus includes a transport unit and a reading unit. The transport unit defines a transport path for transporting the sheet, including an upper path, a lower path positioned below the upper path, and a curved path connecting the upper path and the lower path. . The conveyance unit conveys the sheet from the upper path to the lower path via the curved path. The reading unit reads an image of a sheet conveyed on the conveyance path by the conveyance unit.

  The transport unit includes a chute member that forms a guide surface. The guide surface extends so as to be in contact with the first surface of the sheet facing downward in the upper path and facing upward in the lower path, and guides the sheet in the transport path.

  More specifically, the chute member has a first chute member and a second chute member. The first chute member forms a first guide surface that defines an upper path among the guide surfaces. The second chute member forms a second guide surface that defines a lower path among the guide surfaces. The first chute member has a holding part. The holding unit is recessed from the first guide surface toward the lower path side and holds the reading unit.

  In this image reading apparatus, the conveyance unit conveys the sheet from the upper path to the lower path via the curved path. When the sheet passes through the upper path, the reading unit reads an image on the first surface of the sheet.

Japanese Patent No. 5126270

  By the way, in the conventional image reading apparatus, the first chute member having the holding portion forms the entire first guide surface, and thus tends to be large as a part. Usually, in the manufacturing process, when the reading unit is mounted on the holding unit, the reading unit is mounted in a clean room so that dust, dust, and the like do not enter the periphery of the reading unit. At that time, the larger the size of the component (first chute member) provided with the holding portion, the easier the handling becomes. For this reason, in this image reading apparatus, it may be difficult to efficiently perform the work of mounting the reading unit on the holding unit of the first chute member in the clean room, and it is difficult to improve productivity. On the other hand, when the reading unit is mounted on the holding unit in a place not inside the clean room, there is a problem that dust, dust, and the like easily enter the periphery of the reading unit, leading to deterioration in reading quality.

  The present invention has been made in view of the above-described conventional situation, and an object thereof is to provide an image reading apparatus capable of suppressing a decrease in reading quality and realizing an improvement in productivity.

The image reading apparatus according to the present invention conveys a sheet including an upper path, a lower path positioned below the upper path, and a curved path connecting the upper path and the lower path. A conveying unit that defines a conveying path, and is configured to convey a sheet from one of the upper path and the lower path to the other of the upper path and the lower path via the curved path;
An image reading apparatus comprising: a first reading unit that reads an image of a sheet conveyed by the conveying unit;
The lower path includes, as a reference part, a predetermined portion positioned below the curved path, a first inclined part that slopes downward from the curved path toward the reference part, and the curved path from the reference part. Includes a second inclined portion inclined upward toward the opposite side,
The first reading unit is configured to read an image of the sheet when the sheet passes through one of the first inclined unit and the second inclined unit,
The conveyance portion extends so as to be in contact with the first surface of the sheet facing downward in the upper path and facing upward in the lower path, and forms a guide surface for guiding the sheet in the conveyance path Including members,
The chute member includes a first chute member that forms a first guide surface that defines the upper path of the guide surface, and one of the first inclined portion and the second inclined portion of the guide surface. A second chute member forming a second guide surface to be defined,
The second chute member has a holding portion that is recessed from the second guide surface toward the upper path side and holds the first reading unit,
The first chute member forms a third guide surface that defines the other of the first inclined portion and the second inclined portion of the guide surface.

  In the image reading apparatus of the present invention, the first chute member defines the other of the first inclined portion and the second inclined portion among the guide surfaces that define the conveyance path including the upper path, the lower path, and the curved path. Three guide surfaces are formed. That is, in this image reading apparatus, since the second chute member having the holding portion forms the second guide surface, but does not form the third guide surface, the component size of the second chute member can be reduced. For this reason, in this image reading apparatus, the size of the second chute member is reduced in the manufacturing process, and the handling is less likely to be complicated, and the work of mounting the first reading unit on the holding portion of the second chute member in the clean room is efficient. Can be done well.

  Therefore, in the image reading apparatus of the present invention, it is possible to suppress reading quality deterioration and to improve productivity.

  Further, in this image reading apparatus, it is easy to eliminate the undercut in the mold for forming the second chute member as compared with the case where the second chute member having the holding portion temporarily forms the second guide surface and the third guide surface. . For this reason, in this image reading apparatus, the mold for forming the second chute member can be simplified, and as a result, the manufacturing cost can be reduced.

  The third guide surface may be constituted by lower end edges of a plurality of ribs formed so as to protrude toward the lower path side from the surface facing the opposite side of the first guide surface in the first chute member. desirable. In this case, since the third guide surface is constituted by the lower end edges of the plurality of ribs, the contact area between the sheet and the third guide surface can be reduced, so that the sheet conveyance resistance is reduced.

  The conveyance unit is preferably configured to convey the sheet from the upper path to the lower path via the curved path. In addition, the first reading unit is preferably configured to read an image of the sheet when the sheet passes through the first inclined portion. As for the 2nd chute member, it is desirable to form the 2nd guide surface which prescribes | regulates a 1st inclination part among guide surfaces. The first chute member desirably forms a third guide surface that defines the second inclined portion of the guide surface.

  The image reading apparatus according to the present invention preferably further includes a supply unit that supports the sheet sent to the upper path from the lower side, and a discharge unit that discharges the sheet conveyed in the lower path. The conveyance unit rotates while contacting the sheet sent from the supply unit to the upper path, and separates the separation roller that conveys the sheet toward the curved path, and the sheet that is opposed to the separation roller and is conveyed by the separation roller. It is desirable to include a separation piece that cooperates and separates one by one. The separation roller and the separation piece are preferably attached to the first chute member. According to this configuration, since the separation roller and the separation piece are attached to the common first chute member, variations in the relative positional relationship between them are suppressed, so that the sheet separation performance can be stabilized.

  The conveyance unit preferably includes a detection unit that detects that the sheet fed from the supply unit to the upper path is positioned in the vicinity of the separation roller. And it is desirable for at least one part of a detection part to be attached to the 1st chute member. According to this configuration, by attaching the separation roller and at least a part of the detection unit to the common first chute member, variation in the relative positional relationship between the two is suppressed, so that the detection accuracy of the detection unit is stabilized. be able to.

  The conveyance unit extends to be able to contact a second surface facing the first guide surface while facing the first guide surface from the upper side. The fourth guide surface guides the sheet in the upper path. A first cover member to be formed, and a fifth guide that extends to be able to contact the second surface of the sheet while facing the second guide surface and the third guide surface from below, and guides the sheet in the lower path. It is desirable to include the 2nd cover member which forms a surface.

  The conveyance unit desirably includes a plurality of conveyance rollers that convey the sheet along the conveyance path. Each transport roller is preferably attached to the second cover member. According to this configuration, by attaching the respective conveyance rollers to the common second cover member, variation in the relative positional relationship between the respective conveyance rollers is suppressed, so that the conveyance of the sheet by the conveyance unit can be stabilized.

  The transport unit preferably includes a drive unit for driving each transport roller and a frame member that holds the drive unit. The frame member is preferably attached to the second cover member. According to this configuration, by attaching each conveyance roller and the drive unit to the common second cover member, variations in the relative positional relationship of these components are suppressed, so that the conveyance of the sheet by the conveyance unit is further stabilized. Can be made.

  An image reading apparatus according to the present invention includes a main body having an original support surface formed on the upper surface for supporting an original to be read, and an image of an original that is accommodated in the main body and supported by the original support surface while moving. It is desirable to further include a reading unit, an opening / closing unit supported by the main body so as to be displaceable to a closed position that covers the document support surface and an open position that exposes the document support surface. The conveyance unit and the first reading unit are preferably provided in the opening / closing unit. The second reading unit faces the reference part of the lower path in a state where the opening / closing part is in the closed position, and is the first surface of the sheet when the sheet conveyed by the conveying unit passes the reference part. It is desirable to be configured to read an image of the second surface facing the opposite side.

  The reference unit is preferably set in a range including a position facing the fixed reading position where the second reading unit reads the image of the sheet conveyed by the conveying unit.

1 is a perspective view of an image reading apparatus according to an embodiment. 1 is a schematic side view of an image reading apparatus according to an embodiment. 1 is a schematic partial cross-sectional view of an image reading apparatus according to an embodiment. FIG. 4 is a partial perspective view illustrating a first cover member, a first chute member, a second cover member, and the like according to the image reading apparatus of the embodiment. FIG. 5 is a perspective view illustrating a state in which the first chute member is looked up from below according to the image reading apparatus of the embodiment. It is a perspective view which shows the 2nd chute | shoot member concerning the image reading apparatus of an Example. It is a perspective view which shows the 2nd cover member concerning the image reading apparatus of an Example. FIG. 6 is a partial perspective view illustrating a second chute member, a conveyance roller, a drive unit, and the like in a state assembled to a second cover member according to the image reading apparatus of the embodiment. FIG. 9 is a partial perspective view illustrating a state in which the second chute member is removed from FIG. 8 according to the image reading apparatus of the embodiment. It is a fragmentary perspective view which shows the 2nd cover member concerning the image reading apparatus of a modification.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

(Example)
As shown in FIG. 1, an image reading apparatus 1 according to the embodiment is an example of a specific mode of the image reading apparatus according to 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.

<Configuration>
As shown in FIGS. 1 to 3, 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, a supply tray 91, a discharge tray 92, and a conveyance unit 4. The main body 8 is a flat substantially box-shaped body. As shown in FIG. 1, an operation panel 8 </ b> P such as a touch panel is provided on the front surface of the main body 8.

  As shown in FIGS. 1 and 2, the image forming unit 5 is accommodated in the lower part 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.

  As shown in FIG. 3, 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 the image of the document to be read in a stationary state. 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.

  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. The open / close section 9 covers the document support surface 81A from above in the closed position shown in FIGS. Although not shown, the opening / closing part 9 is displaced to an open position where the document supporting surface 81A is exposed by swinging around the opening / closing axis X9 so that the front end side is displaced upward and backward. As a result, the user can support the document to be read on the document support surface 81A.

  As shown in FIGS. 2 and 3, the reading unit 3 includes a reading sensor 3 </ b> B accommodated in the upper portion of the main body 8, a scanning mechanism (not shown), and a reading sensor 3 </ b> A accommodated in the opening / closing unit 9. doing. The reading sensor 3A is an example of the “first reading unit” in the present invention. The reading sensor 3B is an example of the “second reading unit” in the present invention.

  The reading sensor 3B is located below the document support surface 81A and the reading surface 82A. A scanning mechanism (not shown) reciprocates the reading sensor 3B in the left-right direction below the document support surface 81A in the main body 8 when reading an image of the document supported on the document support surface 81A. A scanning mechanism (not shown) stops the reading sensor 3B at a fixed reading position below the reading surface 82A in the main body 8 when the reading sensor 3B reads an image of the sheet SH conveyed by the conveying unit 4. .

  As will be described later, the reading sensor 3 </ b> A is disposed in the middle of the transport path P <b> 1 in the opening / closing unit 9. As shown in FIG. 3, the reading sensor 3 </ b> A faces the conveyance path P <b> 1 through the third platen glass 83. The reading surface 83A of the third platen glass 83 guides the conveyed sheet SH from above when the reading sensor 3A reads an image of the sheet SH conveyed by the conveying unit 4.

  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. 2 and 3, the supply tray 91, the discharge tray 92, and the transport unit 4 are provided in the opening / closing unit 9. The supply tray 91 is an example of the “supply unit” in the present invention. The discharge tray 92 is an example of the “discharge portion” in the present invention. The supply tray 91 is formed on the right side portion of the opening / closing portion 9 by unfolding the closed cover 9C shown by a solid line in FIG. 1 as shown by a two-dot chain line in FIG. The discharge tray 92 is located below the supply tray 91.

  As shown in FIG. 3, the supply tray 91 supports the sheet SH to be read conveyed by the conveying unit 4 from below. A surface facing the lower side of the sheet SH supported by the supply tray 91 is defined as a first surface SH1. A surface facing the upper side of the sheet SH supported by the supply tray 91, that is, a surface facing the opposite side to the first surface SH1, is defined as a second surface SH2. Images are read onto the discharge tray 92 by the reading sensors 3 </ b> A and 3 </ b> B, and the sheet SH conveyed by the conveyance unit 4 is discharged. When the sheet SH is discharged to the discharge tray 92, the first surface SH1 faces the upper side and the second surface SH2 faces the lower side.

  As shown in FIGS. 3 to 7, the transport unit 4 includes a chute member 100, a first cover member 130, and a second cover member 140. In the chute member 100, the first cover member 130, and the second cover member 140, a plurality of guide surfaces, which will be described later, are formed so as to be able to contact the first surface SH1 or the second surface SH2 of the sheet SH in the opening / closing part 9. Yes. The transport unit 4 defines a transport path P1 shown in FIGS. 2 and 3 as a space surrounded by the plurality of guide surfaces. The conveyance path P1 includes an upper path PA1, a lower path PB1, and a curved path PC1.

  The upper path PA <b> 1 extends from the supply tray 91 to the left end side of the opening / closing part 9. The upper path PA1 is inclined downward at a portion continuing to the supply tray 91, and is inclined upward at a position between a supply roller 41 and a separation roller 42 described later.

  The lower path PB1 is located below the upper path PA1. The lower path PB <b> 1 extends from the left end side of the opening / closing part 9 to the discharge tray 92. The lower path PB1 is inclined downward from the left end side of the opening / closing portion 9 so as to approach the reading surface 82A, extends substantially horizontally along the reading surface 82A, and then upwardly inclined toward the discharge tray 92. ing.

  The curved path PC1 is curved so as to swell leftward, and connects the left end of the upper path PA1 and the left end of the lower path PB1.

  The lower path PB1 has a first inclined part PB11 and a second inclined part with a part extending substantially horizontally to the right side along the reading surface 82A, that is, a predetermined part positioned below the curved path PC1 as a reference part PB10. PB12.

  The first inclined portion PB11 is inclined downward from the lower path PB1 so as to approach the reading surface 82A from the left end side of the opening / closing section 9, that is, from the curved path PC1 toward the reference portion PB10. Part.

  The second inclined portion PB12 is a portion of the lower path PB1 that is inclined upward from the reading surface 82A toward the discharge tray 92, that is, a portion that is inclined upward from the reference portion PB10 toward the opposite side of the curved path PC1. is there.

  The transport unit 4 transports the sheet SH from the upper path PA1 to the lower path PB1 via the curved path PC1 in the transport path P1. The conveyance direction of the sheet SH in the conveyance path P1 is leftward in the upper path PA1, is changed from leftward to the right in the curved path PC1, and is rightward in the lower path PB1. In the transport path P1, the right end side of the upper path PA1 is the upstream side in the transport direction, and the right end side of the lower path PB1 is the downstream side in the transport direction.

  Specific configurations of the chute member 100, the first cover member 130, and the second cover member 140 that define the transport path P1 will be described in detail.

  As shown in FIGS. 2 to 6, the chute member 100 includes a first chute member 110 and a second chute member 120, which are assembled. The first chute member 110 and the second chute member 120 are resin molded products manufactured by, for example, injection molding of a thermoplastic resin. Moreover, the 1st cover member 130 and the 2nd cover member 140 are also resin molded products manufactured by injection molding of a thermoplastic resin, for example.

  As shown in FIGS. 3 and 5, the first chute member 110 extends in the front-rear direction and the left-right direction. As shown in FIG. 3, the right portion of the upper surface of the first chute member 110 is connected to the left edge of the upper surface of the deployed cover 9 </ b> C and is inclined downward to the left, and the left portion of the upper surface of the first chute member 110 is Further, it is inclined upward to the left end side of the opening / closing part 9. The upper surface of the first chute member 110 forms a first guide surface 111 that defines the upper path PA1. The first guide surface 111 extends so as to be in contact with the first surface SH1 of the sheet SH conveyed in the upper path PA1, and guides the sheet SH from below in the upper path PA1.

  As shown in FIGS. 3 and 5, an upper curved surface 116 is formed at the left end portion of the first chute member 110 so as to be curved so as to draw an arc changing from left to down. The upper curved surface 116 defines the upper part of the curved path PC1. The upper curved surface 116 extends so that the upper portion of the curved path PC1 can come into contact with the first surface SH1 of the sheet SH being conveyed, and guides the sheet SH from the lower side and the right side in the upper portion of the curved path PC1.

  As shown in FIGS. 3 and 6, the second chute member 120 extends in the front-rear direction and the left-right direction. The length of the second chute member 120 in the left-right direction is approximately the same as the length in the left-right direction of the left portion of the first chute member 110 that is inclined upward to the left. That is, the length of the second chute member 120 in the left-right direction is about half of the length of the first chute member 110 in the left-right direction. The second chute member 120 is assembled from the lower side with respect to the left portion of the first chute member 110.

  At the left end portion of the second chute member 120, a lower curved surface 126 that is curved so as to draw an arc that changes from downward to right is formed. The lower curved surface 126 defines the lower portion of the curved path PC1. The lower curved surface 126 extends so as to be able to contact the first surface SH1 of the sheet SH conveyed along the lower part of the curved path PC1, and guides the sheet SH from the right side and the upper side in the lower part of the curved path PC1. To do.

  As shown in FIG. 3, the lower surface of the second chute member 120 is connected to the lower curved surface 126 and is inclined downward to the right. The second chute member 120 forms a second guide surface 122 that defines the first inclined portion PB11 of the lower path PB1 by the lower surface thereof. The second guide surface 122 extends so as to be able to contact the first surface SH1 of the sheet SH conveyed through the first inclined portion PB11, and guides the sheet SH from the upper side in the first inclined portion PB11.

  The second chute member 120 has a holding part 129. The holding portion 129 is recessed from the second guide surface 122 to the upper side and the right side, that is, toward the upper path PA1 side. The holding unit 129 holds the reading sensor 3A therein. The opening of the holding part 129 is closed by the third platen glass 83.

  The reading surface 83A of the third platen glass 83 is inclined downward to the right along the first inclined portion PB11. The reading surface 83A, together with the second guide surface 122, defines the first inclined portion PB11. The reading sensor 3A faces the first inclined portion PB11 via the reading surface 83A of the third platen glass 83.

  As shown in FIG. 5, a pair of front and rear pressing member holding portions 117 </ b> A and 117 </ b> A and a spring holding portion 117 </ b> B are provided on the lower surface 112 that is a surface facing the first guide surface 111 of the first chute member 110. Is formed. Each pressing member holding part 117A, 117A supports the front-end part and rear-end part of the pressing member 49 shown in FIG. A biasing spring 49 </ b> S shown in FIG. 3 is disposed between the spring holding portion 117 </ b> B and the pressing member 49.

  As shown in FIG. 3, the pressing member 49 is located adjacent to the second guide surface 122 from the right side, and faces the reading surface 82A from the upper side. The urging spring 49S urges the pressing member 49 toward the reading surface 82A. The lower surface of the pressing member 49 defines the reference portion PB10 of the lower path PB1. The lower surface of the pressing member 49 extends so as to be in contact with the first surface SH1 of the sheet SH conveyed through the reference portion PB10, and guides the sheet SH from the upper side in the reference portion PB10.

  As shown in FIGS. 3 and 5, a plurality of ribs 119 are formed on the lower surface 112 of the first chute member 110. Each rib 119 protrudes from the lower surface 112 to the lower side, that is, toward the second inclined portion PB12 side of the lower path PB1 on the right side of each pressing member holding portion 117A and spring holding portion 117B. The ribs 119 extend in the left-right direction with an interval in the front-rear direction.

  As shown in FIG. 3, the lower and left corners of each rib 119 are adjacent to the pressing member 49 from the right side. The lower end edge 119A of each rib 119 is inclined upward from the lower and left corners to the right. The first chute member 110 forms a third guide surface 113 that defines the second inclined portion PB12 of the lower path PB1 by the lower end edge 119A of each rib 119. The third guide surface 113 extends so as to be able to contact the first surface SH1 of the sheet SH conveyed through the second inclined portion PB12, and guides the sheet SH from the upper side in the second inclined portion PB12.

  That is, the chute member 100 includes the first guide surface 111 and the upper curved surface 116 of the first chute member 110, the lower curved surface 126 and the second guide surface 122 of the second chute member 120, the lower surface of the pressing member 49, the first A guide surface 101 is formed by the third guide surface 113 of the chute member 110. The guide surface 101 extends so as to be in contact with the first surface SH1 of the sheet SH, and guides the sheet SH conveyed by a plurality of conveyance rollers described later along the conveyance path P1.

  As shown in FIGS. 3 and 4, the first cover member 130 is assembled to the first chute member 110 from the upper side. The first cover member 130 extends in the front-rear direction and the left-right direction so as to cover the first chute member 110.

  As shown in FIG. 3, a plurality of ribs 139 are formed on the lower surface of the first cover member 130. Although not shown, the ribs 139 extend in the left-right direction with an interval in the front-rear direction. A lower end edge 139 </ b> A of each rib 139 extends in the left-right direction along the first guide surface 111 while being spaced from the first guide surface 111 of the first chute member 110. And the lower end edge 139A of each rib 139 is curving so that it may draw the circular arc which changes from the left direction to a downward direction, having a space | interval with the upper side curved surface 116 of the 1st chute | shoot member 110. FIG.

  The first cover member 130 forms a fourth guide surface 134 that defines the upper portion of the upper path PA1 and the curved path PC1 by the lower edge 139A of each rib 139. The fourth guide surface 134 extends so as to be able to come into contact with the second surface SH2 of the sheet SH conveyed along the upper portion of the upper path PA1 and the curved path PC1, and the sheet SH in the upper portion of the upper path PA1 and the curved path PC1. Is guided from the upper side and the left side.

  As shown in FIGS. 3, 4, and 7 to 9, the second cover member 140 is assembled to the first chute member 110 and the second chute member 120 from below. The second cover member 140 extends in the front-rear direction and the left-right direction. The lower surface of the opening / closing part 9 is formed by the lower surface of the second cover member 140.

  The upper surface of the right side portion of the second cover member 140 is a discharge tray 92. A rectangular opening 140H elongated in the front-rear direction is provided in the left side portion of the second cover member 140. As shown in FIG. 3, the opening 140 </ b> H is located directly above the reading surface 82 </ b> A in a state where the opening / closing part 9 is in the closed position, and faces the reading surface 82 </ b> A and the pressing member 49. Accordingly, the reading surface 82A defines the reference portion PB10 of the lower path PB1. The reading surface 82A extends so as to be in contact with the second surface SH2 of the sheet SH conveyed through the reference portion PB10, and guides the sheet SH from below in the reference portion PB10. In other words, the reference portion PB10 is set in a range including a position facing the fixed reading position where the reading sensor 3B reads the image of the sheet SH conveyed by the conveying section 4, that is, the position of the reading surface 82A.

  As shown in FIGS. 3 and 7 to 9, in the left portion of the second cover member 140, a fifth guide surface 145A is formed on the left side of the opening 140H, and a fifth guide surface 145B is formed on the right side of the opening 140H. Is formed.

  As shown in FIG. 3, the fifth guide surface 145 </ b> A is curved so as to draw an arc that changes from downward to right while having a space between the lower curved surface 126 of the second chute member 120. The fifth guide surface 145A is inclined downward to the right and reaches the opening 140H while being spaced from the second guide surface 122 of the second chute member 120.

  The fifth guide surface 145A defines the lower portion of the curved path PC1 and the first inclined portion PB11 of the lower path PB1. The fifth guide surface 145A extends so as to be in contact with the lower portion of the curved path PC1 and the second surface SH2 of the sheet SH conveyed through the first inclined portion PB11 of the lower path PB1, and below the curved path PC1. The sheet SH is guided from the left side and the lower side in the first portion PB11 of the side portion and the lower path PB1.

  The fifth guide surface 145B is inclined upward to the right and reaches the discharge tray 92 while being spaced from the third guide surface 113 of the first chute member 110.

  The fifth guide surface 145B defines the second inclined portion PB12 of the lower path PB1. The fifth guide surface 145B extends so as to be able to contact the second surface SH2 of the sheet SH conveyed through the second inclined portion PB12 of the lower path PB1, and the sheet SH in the second inclined portion PB12 of the lower path PB1. Guide from below.

  At the left end of the second cover member 140, a pressing member 149 is provided along the fifth guide surface 145A. The pressing member 149 is biased toward the third platen glass 83 by the biasing spring 149S. The surface of the pressing member 149 facing the third platen glass 83 also defines the first inclined portion PB11 of the lower path PB1 together with the fifth guide surface 145A.

  As shown in FIGS. 8 and 9, the transport unit 4 includes a drive unit 4 </ b> M and a frame member 150. The frame member 150 is attached to a portion of the second cover member 140 on the rear side of the opening 140H and the fifth guide surfaces 145A and 145B with a set screw or the like. The frame member 150 is formed by stamping and bending a steel plate. The frame member 150 is bent so as to rise from the second cover member 140 and extends in the left-right direction. The frame member 150 holds the drive unit 4M at the rising portion. The drive unit 4M includes a plurality of gear groups, pulleys, and the like, and is connected to an electric motor (not shown).

  As shown in FIG. 3, the transport unit 4 includes a supply roller 41, a separation roller 42, a separation piece 43, and a detection unit 47 at a position near the supply tray 91 in the upper path PA <b> 1.

  The supply roller 41 and the separation roller 42 are provided at positions facing the first guide surface 111 of the first chute member 110 from above. The separation roller 42 is assembled to a drive shaft 42S that extends in the front-rear direction. The separation roller 42 is a roller that rotates integrally with the drive shaft 42S.

  As shown in FIG. 4, the front end portion 42F of the drive shaft 42S is rotatably supported by the first chute member 110. Although not shown, the rear end portion of the drive shaft 42S is rotatably supported by the first chute member 110 in the same manner as the front end portion 42F. A gear (not shown) is fixed to the rear end portion of the drive shaft 42S, and the gear meshes with a gear constituting the drive portion 4M shown in FIG. When the driving force of an electric motor (not shown) is transmitted to the driving shaft 42S via the driving unit 4M, the separation roller 42 rotates.

  As shown in FIG. 3, a holder 42F is swingably supported on the drive shaft 42S. The holder 42F protrudes to the right from the drive shaft 42S. The supply roller 41 is rotatably supported on the right side portion of the holder 42F. Although not shown, the holder 42F is provided with a transmission gear group (not shown) that transmits the rotational driving force from the drive shaft 42S to the supply roller 41.

  The separation piece 43 is provided in the first chute member 100 at a position facing the separation roller 42 from below. The separation piece 43 is a plate-like body made of a soft material such as rubber or elastomer. The separation piece 43 is fixed to the upper surface of the separation piece holder 43F supported by the first chute member 100 so as to be swingable. An urging spring 43S is disposed between the separation piece holder 43F and the first chute member 100. The urging spring 43S urges the separation piece holder 43F upward, whereby the separation piece 43 is pressed against the separation roller.

  The supply roller 41 rotates around an axis parallel to the drive shaft 42 </ b> S, applies a conveyance force to the sheet SH supported by the supply tray 91, and sends the sheet SH toward the separation roller 42. The separation roller 42 rotates while being in contact with the sheet SH sent from the supply tray 91 along the upper path PA1, and conveys the sheet SH toward the curved path PC1. The separation piece 43 separates the sheets SH conveyed by the separation roller 42 one by one in cooperation with the separation roller 42.

  As shown in FIGS. 3 and 5, the detection unit 47 includes an actuator 47A and a photo interrupter 47B. The actuator 47A and the photo interrupter 47B are attached to the lower surface 112 side of the first chute member 110. The actuator 47A is supported so as to be swingable between the two ribs 119. The optical path of the photo interrupter 47B is opened and closed by the swing of the actuator 47A.

  As shown in FIG. 3, the upper end portion of the actuator 47 </ b> A protrudes above the first guide surface 111 and is located between the supply roller 41 and the separation roller 42. When the sheet SH supported by the supply tray 91 is inserted to the vicinity of the separation roller 42, the upper end portion of the actuator 47A is pushed by the sheet SH and retracts below the first guide surface 111. Then, the optical path of the photo interrupter 47B is opened or blocked. Accordingly, the detection unit 47 detects that the sheet SH sent out from the supply tray 91 to the upper path PA <b> 1 is positioned in the vicinity of the separation roller 42.

  As shown in FIGS. 3 and 7 to 9, the transport unit 4 includes a first transport roller 44, a pinch roller 44 </ b> P, a second transport roller 45, a pinch roller 45 </ b> P, a discharge roller 48, and a pinch roller 48 </ b> P. . The first transport roller 44, the second transport roller 45, and the discharge roller 48 are examples of the “transport roller” of the present invention.

  As shown in FIG. 3, the first conveyance roller 44 and the pinch roller 44P are disposed on the left side of the separation roller 42 and the separation piece 43 in the upper path PA1, that is, on the downstream side in the conveyance direction. The first transport roller 44 is located on the first guide surface 111 side, and the pinch roller 44P is located on the fourth guide surface 134 side.

  As shown in FIGS. 8 and 9, the first transport roller 44 is assembled to a drive shaft 44 </ b> S that extends in the front-rear direction. The first transport roller 44 is a roller that rotates integrally with the drive shaft 44S.

  The front end 44F of the drive shaft 44S is rotatably supported by the second cover member 140. The rear end portion 44R of the drive shaft 44S is rotatably supported by a frame member 150 attached to the second cover member 140. A gear is fixed to the rear end 44R of the drive shaft 44S, and the gear meshes with a gear constituting the drive unit 4M. The driving force of an electric motor (not shown) is transmitted to the drive shaft 44S via the drive unit 4M, whereby the first transport roller 44 rotates. The pinch roller 44P is driven to rotate by the first conveying roller 44.

  As shown in FIG. 3, the second transport roller 45 and the pinch roller 45P are disposed on the left side of the reading sensor 3A, that is, on the upstream side in the transport direction, in the first inclined portion PB11 of the lower path PB1. . The second transport roller 45 is located on the second guide surface 122 side, and the pinch roller 45P is located on the fifth guide surface 145A side.

  As shown in FIGS. 8 and 9, the second transport roller 45 is assembled to a drive shaft 45 </ b> S that extends in the front-rear direction. The second transport roller 45 is a roller that rotates integrally with the drive shaft 45S.

  The front end 45F of the drive shaft 45S is rotatably supported by the second cover member 140. The rear end portion 45R of the drive shaft 45S is rotatably supported by a frame member 150 attached to the second cover member 140. A gear is fixed to the rear end portion 45R of the drive shaft 45S, and the gear meshes with a gear constituting the drive unit 4M. The driving force of an electric motor (not shown) is transmitted to the drive shaft 45S via the drive unit 4M, whereby the second transport roller 45 rotates. The pinch roller 45P is driven to rotate by the second transport roller 45.

  The first conveyance roller 44 and the pinch roller 44P nip the sheet SH separated one by one by the separation roller 42 and the separation piece 43 and convey the sheet SH to the curved path PC1. The second conveying roller 45 and the pinch roller 45P nip the sheet SH, toward the reading sensor 3A facing the first inclined portion PB11 and the reading sensor 3B stopping at the fixed reading position and facing the reference portion PB10. The sheet SH is conveyed. At this time, the sheet SH is pressed against the reading surface 83 </ b> A by the pressing member 149. Further, the sheet SH is pressed against the reading surface 82 </ b> A by the pressing member 49.

  As shown in FIG. 3, the discharge roller 48 and the pinch roller 48P are disposed at a position facing the discharge tray 92 on the right end side of the second inclined portion PB12 of the lower path PB1. The discharge roller 48 is located on the third guide surface 113 side, and the pinch roller 48P is located on the fifth guide surface 145B side.

  As shown in FIGS. 8 and 9, the discharge roller 48 is assembled to a drive shaft 48S extending in the front-rear direction. The discharge roller 48 is a roller that rotates integrally with the drive shaft 48S.

  The front end 48F of the drive shaft 48S is rotatably supported by the second cover member 140. The rear end portion 48R of the drive shaft 48S is rotatably supported by a frame member 150 attached to the second cover member 140. A pulley is fixed to the rear end 48R of the drive shaft 48S, and the pulley is connected to a pulley constituting the drive unit 4M by a timing belt. When the driving force of an electric motor (not shown) is transmitted to the drive shaft 48S via the drive unit 4M, the discharge roller 48 rotates. The pinch roller 48P is driven to rotate by the discharge roller 48.

  The discharge roller 48 and the pinch roller 48P nip the sheet SH that has passed over the reading surface 82A and discharge it to the discharge tray 92.

<Image reading operation>
In this 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 3B 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 3B reads the image of the document supported on the document support surface 81A. Thereafter, the scanning mechanism (not shown) moves the reading sensor 3B 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 the images on the first surface SH1 and the second surface SH2 of the sheet SH on the supply tray 91 are read, the opening / closing unit 9 is in the closed position. Then, in the reading unit 3, a scanning mechanism (not shown) operates to stop the reading sensor 3B at a fixed reading position below the reading surface 82A. The reading sensor 3B faces the reference portion PB10 of the lower path PB1 at the fixed reading position.

  When the transport unit 4 sequentially transports the sheet SH on the supply tray 91 along the transport path P1, the sheet SH passes through the upper path PA1 and the curved path PC1 and reaches the lower path PB1. Then, the reading sensor 3A reads an image of the first surface SH1 of the sheet SH that passes through the first inclined portion PB11. Next, the reading sensor 3B stopped at the fixed reading position reads an image of the second surface SH2 of the sheet SH that passes through the reference portion PB10. Then, the sheet SH on which the image has been read passes through the second inclined portion PB12 and is discharged to the discharge tray 92 by the discharge roller 48 and the pinch roller 48P.

<Effect>
In the image reading apparatus 1 of the embodiment, the first chute member 110 defines the second inclined portion PB12 among the guide surfaces 101 that define the transport path P1 including the upper path PA1, the lower path PB1, and the curved path PC1. A third guide surface 113 is formed. That is, in the image reading apparatus 1, the second chute member 120 having the holding portion 129 forms the second guide surface 122, but does not form the third guide surface 113. For this reason, as shown in FIG. 6, the component size of the 2nd chute member 120 can be formed small. As a comparative example, when the third guide surface 113 is formed by the second chute member 120, a portion additionally formed on the second chute member 120 is indicated by a two-dot chain line 120K. In this comparative example, it is clear that the component size of the second chute member 120 is increased. For this reason, in the image reading apparatus 1, since the second chute member 120 is reduced in size in the manufacturing process, handling is difficult, and thus the reading sensor 3A is mounted on the holding portion 129 of the second chute member 120 in the clean room. Can be performed efficiently. As a result, in the image reading apparatus 1, it is possible to reliably exclude dust and the like from adhering to the reading sensor 3A attached to the holding unit 129 in the manufacturing process.

  Therefore, in the image reading apparatus 1 of the embodiment, it is possible to suppress the deterioration of the reading quality and improve the productivity.

  Further, in this image reading apparatus 1, compared with a case where the second chute member 120 having the holding portion 129 forms the second guide surface 122 and the third guide surface 113, the mold for forming the second chute member 120 is used. About easy to eliminate undercut. For this reason, in this image reading apparatus 1, the mold of the second chute member 120 can be simplified, and as a result, the manufacturing cost can be reduced.

  Further, in the image reading apparatus 1, as shown in FIGS. 3 and 5, the third guide surface 113 is configured by the lower end edges 119 </ b> A of the plurality of ribs 119, so that the sheet SH and the third guide surface 113 are separated. The contact area can be reduced. Thereby, in this image reading apparatus 1, the conveyance resistance of the sheet SH is reduced, and stable sheet conveyance can be realized.

  In the image reading apparatus 1, as shown in FIGS. 3 and 5, the separation roller 42, the separation piece 43, and the detection unit 47 are attached to a common first chute member 110. Thereby, in this image reading apparatus 1, since the variation in the relative positional relationship between the separation roller 42 and the separation piece 43 is suppressed, the separation performance of the sheet SH can be stabilized. Further, in this image reading apparatus 1, since the variation in the relative positional relationship between the separation roller 42 and the detection unit 47 is suppressed, the detection accuracy of the detection unit 47 can be stabilized.

  Further, in the image reading apparatus 1, as shown in FIGS. 8 and 9, the first conveyance roller 44, the second conveyance roller 45, and the discharge roller 48 are attached to a common second cover member 140. In the image reading apparatus 1, the frame member 150 that holds the drive unit 4 </ b> M is also attached to the second cover member 140. Thereby, in this image reading apparatus 1, since the dispersion | variation in the relative positional relationship of the 1st conveyance roller 44, the 2nd conveyance roller 45, the discharge roller 48, and the drive part 4M is suppressed, the 1st conveyance roller 44, the 2nd conveyance roller The conveyance of the sheet SH by the roller 45 and the discharge roller 48 can be stabilized.

  Further, in the image reading apparatus 1, the images on the first surface SH1 and the second surface SH2 of the sheet SH by the reading sensors 3A and 3B can be favorably read due to the above-described effects.

  While the present invention has been described with reference to the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments and can be appropriately modified and applied without departing from the spirit thereof.

  For example, as illustrated in FIG. 10, the second cover member 140 may be provided with a pressing member support portion 147 that straddles the opening 140 </ b> H in the front-rear direction. In this case, the pair of front and rear pressing member holding portions 117A and 117A and the spring holding portion 117B shown in FIG. 5 can be removed from the first chute member 110 and transferred to the lower surface side of the pressing member support portion 147. As a result, the shape of the first chute member 110 can be simplified.

  In the embodiment, the transport unit 4 is configured to transport the sheet SH from the upper path PA1 via the curved path PC1 to the lower path PB1, but is not limited to this configuration. The conveying unit may be configured to convey the sheet from the lower path to the upper path via the curved path.

  In the embodiment, the chute member 100 includes the first chute member 110 that forms the first guide surface 111 that defines the upper path PA1 in the guide surface 101, and the first inclined portion PB11 in the guide surface 101. A second chute member 120 that defines a second guide surface 122 to be defined, and the first chute member 110 forms a third guide surface 113 that defines the second inclined portion PB12 of the guide surface 101. However, it is not limited to this configuration. The chute member includes a first chute member that forms a first guide surface that defines the upper path of the guide surfaces, and a second chute member that forms a second guide surface that defines the second inclined portion of the guide surfaces. The first chute member may form a third guide surface that defines the first inclined portion of the guide surface.

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

DESCRIPTION OF SYMBOLS 1 ... Image reading apparatus, 8 ... Main-body part, 9 ... Opening / closing part, 4 ... Conveyance part P1 ... Conveyance path, PA1 ... Upper path, PB1 ... Lower path, PC1 ... Curve path SH ... Sheet, SH1 ... First of sheet Surface, SH2 ... second surface of sheet 3A ... first reading unit (reading sensor), 3B ... second reading unit (reading sensor)
PB10: reference portion, PB11: first inclined portion, PB12: second inclined portion 100 ... chute member, 101 ... guide surface, 113 ... third guide surface 110 ... first chute member, 111 ... first guide surface 120 ... first 2 chute members, 122 ... second guide surface 112 ... surface facing the opposite side to the first guide surface in the first chute member (lower surface)
129: Holding section, 119: Rib, 119A: Lower edge of rib 91: Supply section (supply tray), 92: Discharge section (discharge tray)
DESCRIPTION OF SYMBOLS 42 ... Separation roller, 43 ... Separation piece, 47 ... Detection part 130 ... 1st cover member, 134 ... 4th guide surface 140 ... 2nd cover member, 145A, 145B ... 5th guide surface 44, 45, 48 ... Conveyance roller (44 ... 1st conveyance roller, 45 ... 2nd conveyance roller, 48 ... discharge roller)
4M: Drive unit, 150: Frame member, 81A: Document support surface

Claims (13)

An upper path, a lower path positioned below the upper path, and a curved path that connects the upper path and the lower path to define a conveyance path for conveying a sheet, A conveying unit configured to convey a sheet along a conveying direction from a path to the lower path via the curved path;
A first reading sensor that reads an image of a sheet conveyed along the conveyance path by the conveyance unit;
A first chute having a first guide surface that defines at least a portion of the upper path from below and guides the seat;
A separation roller that opposes the first chute and conveys the sheets one by one;
Among the virtual surfaces extending in the direction orthogonal to the transport direction and in the vertical direction, when a specific virtual surface passing through the rotation axis of the separation roller intersects with the lower path as a reference position, A second chute member that includes a second guide surface that defines, from above, at least a part of a path portion from a position that is an upstream end in the conveyance direction in the lower path to the reference position;
The second chute member is a member different from the first chute part, and includes a housing part that is recessed toward the upper path with respect to the second guide surface,
The image reading apparatus, wherein the first reading sensor is accommodated in the accommodating portion with a reading surface facing a lower path from above.   2. The image reading apparatus according to claim 1, wherein the second guide surface is provided on an upstream side and a downstream side in the transport direction with the accommodating portion interposed therebetween. The transport unit includes a first transport roller pair and a second transport roller pair provided on the downstream side in the transport direction with respect to the separation roller,
The image reading apparatus according to claim 1, wherein a curved path is located between the first conveyance roller pair and the second conveyance roller pair.   4. The image reading apparatus according to claim 3, wherein the second chute member and the second conveying roller pair overlap each other when viewed from a direction perpendicular to the specific virtual surface.   5. The image reading apparatus according to claim 3, wherein the second chute member and the first conveying roller pair overlap each other when viewed from a direction parallel to the specific virtual surface. The first guide surface includes an inclined surface that is inclined upward from the upstream side in the transport direction toward the downstream side,
The image reading apparatus according to claim 1, wherein the separation roller is provided at a position facing the inclined surface. In the conveyance path, provided with a discharge roller pair that is provided on the downstream side in the conveyance direction from the first reading sensor, and discharges the sheet from the conveyance path,
The discharge roller located on the lower side of the discharge roller pair is located at a position overlapping the second chute member when viewed from a direction perpendicular to the specific virtual plane. The image reading apparatus according to any one of the above. A main body having a document support surface for supporting a document to be read formed on the upper surface;
A second reading sensor housed in the main body and reading an image of a document supported on the document support surface while moving;
An opening / closing part supported by the main body part so as to be displaceable to a closed position covering the original document support surface and an open position exposing the original document support surface;
The transport unit and the first reading sensor are provided in the opening / closing unit,
The second reading sensor is configured to read an image of a sheet conveyed by the conveyance unit at a predetermined stop position facing the lower path from below in a state where the opening / closing unit is in the closed position. The image reading apparatus according to any one of claims 1 to 7. The lower path includes an inclined path that is inclined with respect to the document support surface;
The second chute member defines a part of the inclined path;
10. The image reading apparatus according to claim 8, wherein the reading surface of the first reading sensor is disposed in an inclined posture along an inclined path. 11.   10. The image reading apparatus according to claim 8, wherein the second chute member is positioned between an edge of the document support surface near the curved path and the curved path. A separation piece facing the separation roller and separating sheets conveyed by the separation roller one by one in cooperation with the separation roller;
The image reading apparatus according to claim 1, wherein the separation piece is attached to the first chute member. The transport section extends from the top to face the first guide surface, and forms a third guide surface that defines the upper path from above, a first cover member;
6. The second cover member according to claim 1, further comprising a second cover member that forms a fourth guide surface that defines the lower path from below while facing the second chute member from below. Image reading apparatus.   The said 2nd conveyance roller pair is located in the conveyance direction upstream of the said 2nd chute member, and is supported by the member different from the said 2nd chute member. The image reading apparatus described in 1.

Images