Image reading apparatus

Abstract

The invention provides an image reading apparatus which enables the posture of a conveyed medium to be appropriate. An image reading apparatus includes: a feeding unit having a feed roller and a separation roller; a first conveyance roller pair disposed downstream of the feeding portion in the conveyance direction; a second transport roller pair disposed downstream of the first transport roller pair in the transport direction; and a reading unit disposed downstream of the second transport roller pair in the transport direction, the feeding unit transporting the medium while clamping the medium with a clamping width narrower than the width of the medium, and the first transport roller pair transporting the medium while clamping the medium with a clamping width wider than the clamping width of the feeding unit. The second transport roller pair passes through the plurality of roller pairs so as to transport the medium at a nip width that is wider than the nip width of the first transport roller pair.

Description

Technical Field

[0001] The present invention relates to an image reading device. Background Art

[0002] Various image reading devices have been used. Among them, some read images of conveyed media. For example, Patent Document 1 discloses a feeding device that bends the medium upward toward a reading section midway along the medium's conveyance path while conveying it.

[0003] In the feeder device disclosed in Patent Document 1, the medium, which is deformed into a V-shape when viewed from the conveying direction, is conveyed along a conveying path that curves upward, thereby correcting the deformation of the medium. In this manner, the medium is sometimes deformed into a V-shape in the feeder when viewed from the conveying direction, and then, when viewed from a width direction intersecting the conveying direction, the V-shaped medium is flattened and flattened in the opposing area of ​​the reading section by bending the medium when viewed from the width direction intersecting the conveying direction. However, in conventional image reading devices that read images of conveyed media, such as the feeder device disclosed in Patent Document 1, even with this configuration, it is difficult to maintain the proper posture of the conveyed medium. For example, in a configuration that excessively bends the deformed V-shaped medium, it is sometimes impossible to properly convey sturdy media such as thick paper. Furthermore, there are cases where the deformed V-shaped medium cannot be completely flattened in the opposing area of ​​the reading section, resulting in reduced reading accuracy.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-120742 Summary of the Invention

[0005] The image reading device of the present invention for solving the above-mentioned problems is characterized by comprising: a feeding section having a feed roller and a separation roller that clamps a medium together with the feed roller and separates the medium, and conveys the medium in a conveying direction along a conveying path; a first conveying roller pair that is arranged downstream of the feeding section in the conveying direction and conveys the medium in the conveying direction while clamping the medium; a second conveying roller pair that is arranged downstream of the first conveying roller pair in the conveying direction and conveys the medium in the conveying direction; and a reading section that is arranged adjacent to the second conveying roller. The comparison unit is located downstream of the conveying direction and reads an image of the medium. The feeding unit clamps the medium in a width direction intersecting the conveying direction with a clamping width narrower than the width of the medium and conveys it in the conveying direction. The first conveying roller pair clamps the medium in the width direction with a clamping width wider than the clamping width of the feeding unit and conveys it in the conveying direction. The second conveying roller pair uses multiple roller pairs to convey the medium in the width direction with a clamping width wider than the clamping width of the first conveying roller pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is a side view of the image reading device according to the first embodiment of the present invention.

[0007] Figure 2 for Figure 1 1 is an enlarged view of a portion of the image reading device and is a side view of the periphery of the feeding portion, the first conveying roller pair, and the second conveying roller pair.

[0008] Figure 3 for Figure 1 A perspective view of a base unit of an image reading device.

[0009] Figure 4 for Figure 1 A perspective view of an opening and closing unit of an image reading device.

[0010] Figure 5 This is a schematic side view of an image reading device according to a second embodiment of the present invention.

[0011] Figure 6 for Figure 5 A schematic side view of the feeding portion, the first conveying roller pair, the second conveying roller pair, and the surrounding areas of the image reading device.

[0012] Figure 7 for Figure 5 A rear view of the periphery of a second conveying roller pair of the image reading device. DETAILED DESCRIPTION

[0013] First, the present invention will be briefly described.

[0014] The image reading device of the first embodiment of the present invention for solving the above-mentioned problems is characterized in that it comprises: a feeding section having a feed roller and a separation roller that clamps a medium together with the feed roller and separates the medium, and conveys the medium in a conveying direction along a conveying path; a first conveying roller pair that is arranged downstream of the feeding section in the conveying direction and conveys the medium in the conveying direction while clamping the medium; a second conveying roller pair that is arranged downstream of the first conveying roller pair in the conveying direction and conveys the medium in the conveying direction; and a reading section that is arranged adjacent to the second conveying roller pair. The feed roller pair is closer to the downstream of the conveying direction and reads the image of the medium. The feeding portion clamps the medium in the width direction intersecting the conveying direction with a clamping width narrower than the width of the medium and conveys it in the conveying direction. The first conveying roller pair clamps the medium in the width direction with a clamping width wider than the clamping width of the feeding portion and conveys it in the conveying direction. The second conveying roller pair uses multiple roller pairs to convey the medium in the width direction with a clamping width wider than the clamping width of the first conveying roller pair.

[0015] According to this method, the feeder unit holds the medium in the width direction with a narrower gripping width than the width of the medium while conveying it in the conveying direction. This allows the medium to be fed in a V-shaped position, thus preventing feeding defects. Furthermore, the first conveyor roller pair holds the medium with a wider gripping width than the feeder unit's gripping width while conveying it, while the second conveyor roller pair, using multiple roller pairs, conveys the medium with a wider gripping width than the gripping width of the first conveyor roller pair. This configuration allows the V-shaped medium to be appropriately flattened before reaching the reader unit. This ensures that the posture of the conveyed medium is optimized.

[0016] The image reading device of the second mode of the present invention is a mode subordinate to the first mode, and is characterized in that the clamping position in the feeding portion and the clamping position in the first conveying roller pair are arranged in the horizontal direction, and in the first conveying roller pair, the upper roller and the lower roller are arranged opposite to each other in the up and down directions, and the rotation axis of the upper roller is arranged downstream in the conveying direction compared to the rotation axis of the lower roller.

[0017] According to this configuration, the rotation axis of the upper roller in the first conveyor roller pair is positioned downstream in the conveying direction relative to the rotation axis of the lower roller. This configuration allows the media to be bent at an appropriate angle when viewed widthwise, allowing the V-shaped media to be appropriately flattened before reaching the reader. Furthermore, the clamping position in the feeder section and the clamping position in the first conveyor roller pair are aligned horizontally. While a configuration in which the conveyor path faces upward near the feeder section would tend to increase the height of the device, this configuration minimizes this increase in height.

[0018] The image reading device of the third embodiment of the present invention is a method subordinate to the second embodiment, characterized in that the first conveying roller pair is constructed so that when viewed from the width direction, the line connecting the rotation axis of the upper roller and the rotation axis of the lower roller forms an angle of greater than 3° and less than 12° relative to the line extending from the rotation axis of the lower roller toward the vertical upward direction.

[0019] According to this method, when viewed in the width direction, the line connecting the rotation axes of the upper and lower rollers forms an angle of 3° or more and 12° or less relative to a line extending vertically upward from the rotation axis of the lower roller. This configuration prevents feeding failures while allowing the V-shaped medium to be properly flattened before reaching the reader.

[0020] An image reading device according to a fourth aspect of the present invention is an aspect belonging to any one of the first to third aspects, wherein a nipping position in the feeding section is arranged at a position higher than a nipping position in the first transport roller pair.

[0021] According to this method, the clamping position in the feed section is located higher than the clamping position in the first conveyor roller pair. This configuration allows the V-shaped medium to be appropriately flattened before reaching the reader section, eliminates the need for a structure where the conveying path faces upward near the feed section, and reduces the size of the device in the height direction.

[0022] The image reading device of the fifth embodiment of the present invention is a method subordinate to the fourth embodiment, and is characterized in that it is constructed so that the line connecting the clamping position in the feeding portion and the clamping position in the first conveying roller pair forms an angle of greater than 2° and less than 15° relative to the horizontal line.

[0023] According to this method, the line connecting the nip position in the feed section and the nip position in the first conveyor roller pair forms an angle of at least 2° and less than 15° relative to the horizontal. This configuration prevents feeding defects while properly flattening V-shaped media before reaching the reader. This allows for proper conveyance of even sturdy media such as thick paper.

[0024] An image reading device according to a sixth aspect of the present invention is the aspect belonging to any one of the first to fifth aspects, wherein a nip width of the second transport roller pair is wider than a width of the medium in the width direction.

[0025] According to this aspect, the clamping width of the second conveying roller pair is wider than the width of the medium in the width direction. By setting such a structure, the V-shaped medium can be appropriately flattened across the entire width direction before reaching the reading unit.

[0026] An image reading device according to a seventh aspect of the present invention is based on the sixth aspect, wherein the second transport roller pair sandwiches at least a center portion and both end portions of the medium in the width direction.

[0027] According to this method, the second conveyor roller pair clamps at least the center and both ends of the medium in the width direction. This configuration allows the V-shaped medium to be appropriately flattened across the entire width direction before reaching the reading unit, while simplifying the structure of the second conveyor roller pair.

[0028] The image reading device of the eighth mode of the present invention is a mode belonging to any one of the first mode to the seventh mode, and is characterized in that the reading unit includes: a first reading unit, which reads the image of the first side of the medium; and a second reading unit, which is arranged opposite to the first reading unit and reads the image of the second side of the medium on the opposite side of the first side.

[0029] According to this method, the reading unit includes a first reading unit that reads an image on the first side of the medium, and a second reading unit that is arranged opposite the first reading unit and reads an image on the second side of the medium. This configuration shortens the length required to arrange the first and second reading units in the conveyance direction, thereby preventing the device from becoming larger in the depth direction.

[0030] Example 1

[0031] Hereinafter, an embodiment of the image reading device 1 according to the present invention will be described below. First, regarding the image reading device 1A according to the embodiment 1 of the image reading device 1 according to the present invention, Figures 1 to 4 to illustrate. In the following description, as shown in the accompanying drawings, three mutually orthogonal axes are set as X-axis, Y-axis, and Z-axis respectively. The directions indicated by the arrow marks of the three axes (X, Y, Z) are the + directions of each direction, and the opposite directions are the - directions. The Z-axis direction is equivalent to the vertical direction, that is, the direction of gravity, the +Z direction indicates the vertical top, and the -Z direction indicates the vertical bottom. The X-axis direction and the Y-axis direction are equivalent to the horizontal direction, wherein the X-axis direction corresponds to the width direction B. The +Y direction indicates the front direction of the device, and the -Y direction indicates the rear direction of the device. The +X direction indicates the right direction of the device, and the -X direction indicates the left direction of the device.

[0032] The image reading device 1A of this embodiment is a scanner capable of reading an image on a medium M serving as an original document. Here, the term "image" refers to content visually recorded on the medium, such as text, graphics, tables, pictures, and photographs. The medium M is not limited to sheets but also includes cards, booklets, and the like. The image reading device 1 is not limited to a scanner and may also be a copier, facsimile machine, or the like.

[0033] As in Figure 1 As shown in FIG. 1 , the image reading device 1A of this embodiment includes a first reading unit 4A and a second reading unit 4B as the reading unit 4 for reading an image of a medium M. The first reading unit 4A and the second reading unit 4B are disposed opposite each other on a conveyance path 5 for conveying the medium M. The first reading unit 4A can read an image on the first side M1 of the medium M, and the second reading unit 4B can read an image on the second side M2 ​​of the medium M. The first reading unit 4A and the second reading unit 4B may be, for example, CIS (Contact Image Sensor) sensors or CCD (Charge Coupled Device) sensors.

[0034] The image reading device 1A of this embodiment includes a first conveyor roller pair 20 and a second conveyor roller pair 30. The first conveyor roller pair 20 conveys the medium M in the conveyance direction A along the conveyance path 5 and is disposed upstream of the reading unit 4 in the conveyance direction A. The second conveyor roller pair 30 is disposed downstream of the first conveyor roller pair 20 and upstream of the reading unit 4 in the conveyance direction A. Furthermore, the image reading device 1A includes a plurality of conveyor roller pairs 6 disposed downstream of the reading unit 4 in the conveyance direction A. Specifically, the conveyor roller pair 6A, the conveyor roller pair 6B, the conveyor roller pair 6C, and the conveyor roller pair 6D.

[0035] A feeding portion 10 is provided upstream of the first conveying roller pair 20 in the conveying direction A. Figure 2 As shown in FIG, the feeding unit 10 is a roller pair consisting of a feed roller 11 that rotates about a rotation axis 11A and a separation roller 12 that rotates about a rotation axis 12A. The feed roller 11 is a drive roller that is rotated by power from a drive unit (e.g., a motor) (not shown) and conveys the medium M in a conveyance direction A. The separation roller 12 is a drive roller that is rotated by power from a drive unit (e.g., a motor) (not shown) and separates a single sheet of medium M from a plurality of sheets of medium M.

[0036] Here, the separation roller 12 rotates in a direction that feeds the medium M upstream in the conveying direction A. The separation roller 12 is equipped with a torque limiter (not shown). When a torque exceeding a set value is applied to the torque limiter, the separation roller 12 is driven to rotate in a direction that feeds the medium M downstream in the conveying direction A. A pickup roller 13 is disposed upstream of the separation roller 12. The pickup roller 13 is a drive roller that is rotated by power from a drive unit (e.g., a motor) (not shown) and feeds the medium M in the conveying direction A.

[0037] The first and second conveyor roller pairs 20, 30, and the conveyor roller pairs 6A, 6B, 6C, and 6D that convey the medium M in the conveying direction A also include drive rollers that are rotated by power from a drive unit (e.g., a motor) (not shown). The lower roller 22 of the first conveyor roller pair 20 and the lower roller 32 of the second conveyor roller pair 30 serve as drive rollers. Alternatively, the upper roller 21 and lower roller 22 of the first conveyor roller pair 20 may both serve as drive rollers. Furthermore, the upper roller 31 and lower roller 32 of the second conveyor roller pair 30 may both serve as drive rollers.

[0038] As in Figure 1 As shown in FIG, the conveying path 5 is a substantially straight line extending from the feed roller 11 to the conveying roller pair 6A, namely, the straight path 5A. Downstream of the straight path 5A in the conveying direction A, that is, downstream of the conveying roller pair 6A in the conveying direction A, a curved reversing path 5B is provided as the conveying path 5. The conveying roller pair 6B, the conveying roller pair 6C, and the conveying roller pair 6D are disposed on the curved reversing path 5B. The discharge receiving portion 7, which receives the medium M discharged from the curved reversing path 5B, is located above the straight path 5A, thereby achieving a more compact device.

[0039] As in Figure 1As shown in FIG, the medium M, which is the image reading document, is placed on the medium placement portion 8. The medium M on the medium placement portion 8 is conveyed on the conveying path 5 and is finally discharged to the discharge receiving portion 7. The medium placement portion 8 is constructed in a manner that moves up and down. When the medium M placed on the medium placement portion 8 is fed in the conveying direction A, first, the medium placement portion 8 is driven by a driving source (not shown) to move upward, and stops in a state in which the uppermost medium M among the placed media M comes into contact with the pickup roller 13. In this state, the pickup roller 13 rotates to feed the medium M in the conveying direction A, so that the top end of the medium M in the conveying direction A reaches the clamping position of the roller pair of the feed roller 11 and the separation roller 12.

[0040] Although multiple sheets of media M can be stacked on the media placement section 8, if the stacked media M is in an overlapped state, the media M is separated into a single sheet by the separation roller 12. This single sheet of media is then conveyed in the conveyance direction A by the first and second conveyance roller pairs 20 and 30, and the image of the media M is read by the reader 4. The media M, whose image has been read by the reader 4, is fed to the curved reversing path 5B by the conveyance roller pair 6A, conveyed by the conveyance roller pair 6A, the conveyance roller pair 6B, the conveyance roller pair 6C, and the conveyance roller pair 6D, and then discharged to the discharge receiving section 7 by the conveyance roller pair 6D, which also serves as the discharge section.

[0041] As in Figure 1 As shown in FIG. 1 , the image reading device 1A comprises a base unit 2 and an opening and closing unit 3. The opening and closing unit 3 is configured to be able to be rotated in the vertical direction relative to the base unit 2 and opened and closed by an opening and closing mechanism (not shown). The base unit 2 includes a second reading section 4B, a separation roller 12, the lower roller 22 of the first conveyor roller pair 20, the lower roller 32 of the second conveyor roller pair 30, and the drive rollers of the conveyor roller pair 6A, the conveyor roller pair 6B, the conveyor roller pair 6C, and the conveyor roller pair 6D.

[0042] The opening and closing unit 3 includes the first reading section 4A, the pickup roller 13, the feed roller 11, the upper roller 21 of the first conveying roller pair 20, the upper roller 31 of the second conveying roller pair 30, the conveying roller pair 6A, the conveying roller pair 6B, the conveying roller pair 6C, and the driven rollers of the conveying roller pair 6D. When the opening and closing unit 3 is closed relative to the base unit 2, as in Figure 1 As shown in the figure, the feed roller 11 and the separation roller 12, the upper roller 21 and the lower roller 22, the upper roller 31 and the lower roller 32, the conveying roller pair 6A, the conveying roller pair 6B, the conveying roller pair 6C and the respective driving rollers and the respective driven rollers of the conveying roller pair 6D are arranged in an opposing manner.

[0043] When the opening and closing unit 3 is open relative to the base unit 2, although not shown in the figure, the feed roller 11 and separation roller 12, the upper roller 21 and lower roller 22, the upper roller 31 and lower roller 32, and the driving rollers and driven rollers of the conveyor roller pairs 6A, 6B, 6C, and 6D are not aligned with each other. In other words, the facing surfaces of the base unit 2 and the opening and closing unit 3 are exposed, allowing the user to access the conveyor path 5 corresponding to these facing surfaces.

[0044] Next, the details of the feeder 10, the first conveying roller pair 20, and the second conveying roller pair 30, which are the main components of the image reading device 1A of this embodiment, will be described. As described above, the image reading device 1A of this embodiment includes the feeder 10, which has a feed roller 11 and a separation roller 12 that, together with the feed roller 11, sandwiches and separates the medium M. The feeder 10 transports the medium M in the transport direction A along the transport path 5. Furthermore, the feeder 10 includes the first conveying roller pair 20, which is positioned downstream of the feeder 10 in the transport direction A and sandwiches and sandwiches the medium M while transporting it in the transport direction A. Furthermore, the image reading device 1A includes the second conveying roller pair 30, which is positioned downstream of the first conveying roller pair 20 in the transport direction A and transports the medium M in the transport direction A. Furthermore, a reading unit 4 is provided. The reading unit 4 is arranged downstream of the second conveying roller pair 30 in the conveying direction A and reads an image on the medium M.

[0045] Here, as in Figure 3 As shown in FIG, the feeding unit 10 feeds the medium M in the conveying direction A while holding the medium M with a clamping width L2 that is narrower than the width L1 of the medium M in the width direction B intersecting the conveying direction A. Therefore, the medium M can be fed in a V-shaped state when viewed from the conveying direction A, thereby effectively applying a feeding force to the medium M and suppressing feeding defects.

[0046] In addition, as in Figure 3 as well as Figure 4As shown in FIG. 1 , the first conveyor roller pair 20 conveys the medium M in the conveyance direction A while holding it in the width direction B with a nip width L3 that is wider than the nip width L2 of the feed unit 10. The second conveyor roller pair 30, comprising multiple roller pairs arranged in the width direction B, conveys the medium M in the conveyance direction A with a nip width L4 that is wider than the nip width L3 of the first conveyor roller pair 20. This configuration allows the V-shaped medium M to be appropriately flattened before reaching the reading unit 4. Therefore, the image reading device 1A of this embodiment can optimize the posture of the conveyed medium M.

[0047] Furthermore, the image reading device 1A of this embodiment is configured such that the nip width L4 of the second conveying roller pair 30 is wider than the width L1 of the medium M in the width direction B. This configuration allows the V-shaped medium M to be appropriately flattened over the entire width direction B before reaching the reading unit 4 .

[0048] In the image reading device 1A of this embodiment, the second transport roller pair 30 clamps at least the center and both ends of the medium in the width direction B. However, this configuration is preferred. This is because, without necessarily using rollers that are long and require high-precision manufacturing across the entire width direction, the second transport roller pair 30 can be simplified while ensuring that the V-shaped medium M is appropriately flattened across the entire width direction B before reaching the reading unit 4.

[0049] In addition, as in Figure 2 As shown in FIG. , in the image reading device 1A of this embodiment, the clamping position P1 of the feed unit 10 and the clamping position P2 of the first conveyor roller pair 20 are arranged in the horizontal direction. A configuration in which the conveyor path 5 faces upward near the feed unit 10 would tend to increase the height of the device. However, by adopting this configuration, the image reading device 1A of this embodiment can suppress this increase in height. Furthermore, since the image reading device 1 may not be installed in a strictly horizontal position, the term "horizontal" herein is sufficient as long as it is substantially horizontal, and is intended to include even slight deviations from the strictly horizontal direction.

[0050] And, as in Figure 2As shown in FIG, the upper roller 21 and the lower roller 22 of the first conveying roller pair 20 are arranged to face each other in the vertical direction, and the rotation axis 21A of the upper roller 21 is arranged downstream of the rotation axis 22A of the lower roller 22 in the conveying direction A. With this configuration, the image reading device 1A of this embodiment can be configured to bend the medium M at an appropriate angle when viewed in the width direction B, and can appropriately flatten the V-shaped medium M before reaching the reading unit 4.

[0051] Specifically, in the image reading device 1A of this embodiment, as shown in FIG. Figure 2 As shown in FIG. 1 , the first conveying roller pair 20 is configured such that, when viewed in the width direction B, a line LA connecting the rotation axis 21A of the upper roller 21 and the rotation axis 22A of the lower roller 22 forms an angle θ1 of not less than 3° and not more than 12° with respect to a line LB extending vertically upward from the rotation axis 22A of the lower roller 22. With this configuration, the image reading device 1A of this embodiment can appropriately flatten the V-shaped medium M before it reaches the reading unit 4 while suppressing feeding defects.

[0052] In addition, as in Figure 2 As shown in the figure, the upper roller 31 and lower roller 32 of the second conveyor roller pair 30 are arranged to face each other in the vertical direction, and the rotation axis 31A of the upper roller 31 and the rotation axis 32A of the lower roller 32 are arranged at the same position in the conveying direction A. Furthermore, the nip position P3 between the upper roller 31 and the lower roller 32 of the second conveyor roller pair 30 is located horizontally with respect to the nip position P2 between the upper roller 21 and the lower roller 22 of the first conveyor roller pair 20. This structure maintains the linear path 5A horizontally, thereby preventing the device from increasing in height.

[0053] Furthermore, as described above, in the image reading device 1A of this embodiment, the reading unit 4 includes a first reading unit 4A and a second reading unit 4B. The first reading unit 4A reads an image of the first side M1 of the medium M, and the second reading unit 4B is disposed opposite the first reading unit 4A and reads an image of the second side M2 ​​of the medium M, which is opposite the first side M1. This configuration of the image reading device 1A of this embodiment reduces the length in the Y-axis direction required by disposing the first reading unit 4A and the second reading unit 4B in the conveyance direction A, thereby preventing an increase in the size of the device.

[0054] Example 2

[0055] Next, regarding the image reading device 1B of the second embodiment, reference will be made to Figures 5 to 7 Here, Figure 5 The image reading device 1A corresponding to the embodiment 1 Figure 1 , Figure 6 The image reading device 1A corresponding to the embodiment 1 Figure 2 In addition, the image reading device 1B of this embodiment is the same as the image reading device 1A of the first embodiment except for the following description, and therefore has the same features as the image reading device 1A of the first embodiment. Figures 5 to 7 In the embodiment 1, the same parts as those in the embodiment 1 are represented by the same symbols and detailed descriptions are omitted.

[0056] As in Figure 5 As shown in FIG, the image reading device 1B of this embodiment is different from the Figure 1 The image reading device 1A of Example 1 shown in FIG. 1 similarly includes a feeding unit 10 having a feed roller 11 and a separation roller 12 that, together with the feed roller 11, sandwiches and separates the medium M. The feeding unit 10 conveys the medium M in the conveyance direction A along the conveyance path 5. Furthermore, the feeding unit 10 includes a first conveyance roller pair 20 that is positioned downstream of the feeding unit 10 in the conveyance direction A and sandwiches and sandwiches the medium M while conveying it in the conveyance direction A. Furthermore, the feeding unit 10 includes a second conveyance roller pair 30 that is positioned downstream of the first conveyance roller pair 20 in the conveyance direction A and sandwiches the medium M while conveying it in the conveyance direction A. Furthermore, the feeding unit 10 includes a reading unit 4 that is positioned downstream of the second conveyance roller pair 30 in the conveyance direction A and reads an image on the medium M.

[0057] Furthermore, in the image reading device 1B of this embodiment, similarly to the image reading device 1A of Embodiment 1, the feed unit 10 conveys the medium M in the conveyance direction A while holding the medium M in the width direction B intersecting the conveyance direction A with a nip width L2 that is narrower than the width L1 of the medium M. Furthermore, the first conveying roller pair 20 conveys the medium M in the conveyance direction A while holding the medium M in the width direction B with a nip width L3 that is wider than the nip width L2 of the feed unit 10. The second conveying roller pair 30, comprising a plurality of roller pairs arranged in the width direction B, conveys the medium M in the conveyance direction A with a nip width L4 that is wider than the nip width L3 of the first conveying roller pair 20.

[0058] On the other hand, as in Figure 5As shown in FIG. 1 , the image reading device 1B of this embodiment differs from the image reading device 1A of Example 1 in that the first reading section 4A and the second reading section 4B are not opposed to each other, and a transport roller pair 6E is provided between the first reading section 4A and the second reading section 4B on the transport path 5. Furthermore, the image reading device 1B of this embodiment differs from the image reading device 1A of Example 1 in the structure of the linear path 5A in the transport path 5, as well as the structure of the feed section 10 and the first transport roller pair 20.

[0059] Specifically, in the image reading device 1B of this embodiment, as in Figure 6 As shown in FIG, the nip position P1 of the feed unit 10 is located higher than the nip position P2 of the first conveyor roller pair 20. This configuration allows the V-shaped medium M to be appropriately flattened before reaching the reader 4. Furthermore, the conveyance path 5 can be directed downward near the feed unit 10, thereby preventing the conveyance path 5 from being directed upward. This can suppress an increase in the height of the device.

[0060] Furthermore, in a configuration where the nip position P1 is positioned higher than the nip position P2, it is preferable that the line LC connecting the nip position P1 in the feed unit 10 and the nip position P2 in the first conveyor roller pair 20 form an angle of at least 2° and less than 15° relative to the horizontal line LD. This configuration prevents feeding defects while allowing the V-shaped medium M to be properly flattened before reaching the reading unit 4. This allows for proper conveyance of even sturdy media M, such as thick paper.

[0061] Here, we explain why it is preferable to configure the line LC connecting the nip positions P1 and P2 to form an angle of at least 2° and less than 15° relative to the horizontal line LD. Table 1 below evaluates the transportability (thick paper transportability) when thick paper is used as the medium M, and whether commercially available copy paper can be properly flattened near the reading unit 4 (copy paper deflection) when the medium M is used, with A being considered acceptable and B being considered unacceptable. The transportability of thick paper is determined by whether the thick paper can be transported smoothly, while the deflection of copy paper is determined by whether the flatness of the medium M near the reading unit 4 is unpredictable. As shown in Table 1 below, if the line LC connecting the nip positions P1 and P2 is less than 2° relative to the horizontal line LD, the transportability of thick paper is unacceptable, and if the line LC connecting the nip positions P1 and P2 is more than 15° relative to the horizontal line LD, the deflection of copy paper is unacceptable.

[0062] Table 1

[0063] Less than 2° 2° or more and 15° or less More than 15° Thick paper transportability A A B Deflection of copy paper B A A

[0064] Furthermore, in the image reading device 1B of this embodiment, the structure of the second conveying roller pair 30 is also different from that of the image reading device 1A of the embodiment 1. Specifically, Figure 7 As shown in FIG. , rollers having narrower widths than the upper rollers 31 and lower rollers 32 of the image reading device 1A of Example 1 are arranged more frequently in the width direction B. However, similarly to the second conveyor roller pair 30 of the image reading device 1A of Example 1, the second conveyor roller pair 30 of the image reading device 1B of this embodiment is configured such that the nip width L4 of the second conveyor roller pair 30 is wider than the width L1 of the medium M in the width direction B.

[0065] The present invention is not limited to the above-described embodiments and can be implemented in various configurations without departing from its main purpose. In addition, in order to solve part or all of the above-described problems, or to achieve part or all of the above-described effects, the technical features in the embodiments corresponding to the technical features in the various embodiments described in the Summary of the Invention column can be appropriately replaced or combined. In addition, as long as the technical features are not described as essential in this specification, they may be appropriately deleted.

[0066] Explanation of symbols

[0067] 1…image reading device; 1A…image reading device; 1B…image reading device; 2…base unit; 3…opening and closing unit; 4…reading section; 4A…first reading section; 4B…second reading section; 5…conveying path; 5A…straight path; 5B…curved reversing path; 6…conveying roller pair; 6A…conveying roller pair; 6B…conveying roller pair; 6C…conveying roller pair; 6D…conveying roller pair; 6E…conveying roller pair; 7…discharging receiving section; 8…medium placement section; 10…feeding section; 11…feed roller; 11A…rotating shaft; 12…separating roller; 12 A…rotation axis; 13…pick-up roller; 20…first conveying roller pair; 21…upper roller; 21A…rotation axis; 22…lower roller; 22A…rotation axis; 30…second conveying roller pair; 31…upper roller; 31A…rotation axis; 32…lower roller; 32A…rotation axis; L1…width; L2…clamping width; L3…clamping width; L4…clamping width; LA…line; LB…line; LC…line; LD…line; M…medium; M1…first side; M2…second side; P1…clamping position; P2…clamping position; P3…clamping position.

Claims

1. An image reading device, characterized in that have: a feeding portion including a feed roller and a separation roller that sandwiches the medium together with the feed roller and separates the medium, and conveys the medium in a conveying direction along a conveying path; a first conveying roller pair disposed downstream of the feeding portion in the conveying direction and configured to convey the medium in the conveying direction while holding the medium; a second conveying roller pair disposed downstream of the first conveying roller pair in the conveying direction and conveying the medium in the conveying direction; a reading unit arranged downstream of the second conveying roller pair in the conveying direction and configured to read an image on the medium; The feeding portion feeds the medium in the conveying direction while holding the medium with a holding width narrower than the width of the medium in a width direction intersecting the conveying direction. The first conveying roller pair conveys the medium in the conveying direction while holding the medium with a gripping width wider than the gripping width of the feeding portion in the width direction. The second conveying roller pair conveys the medium in the conveying direction with a nip width wider in the width direction than the nip width of the first conveying roller pair by using a plurality of roller pairs.

2. The image reading device according to claim 1, wherein The nip position in the feeding portion and the nip position in the first conveying roller pair are arranged in the horizontal direction, In the first transport roller pair, an upper roller and a lower roller are disposed facing each other in the vertical direction, and a rotation axis of the upper roller is disposed downstream of a rotation axis of the lower roller in the transport direction.

3. The image reading device according to claim 2, wherein The first conveying roller pair is configured such that a line connecting the rotation axes of the upper roller and the lower roller forms an angle of 3° to 12° with respect to a line extending vertically upward from the rotation axis of the lower roller when viewed in the width direction.

4. The image reading device according to claim 1, wherein The nip position in the feeding portion is arranged at a higher position than the nip position in the first conveying roller pair.

5. The image reading device according to claim 4, wherein The line connecting the nip position in the feeding portion and the nip position in the first conveying roller pair is configured such that an angle of not less than 2° and less than 15° is formed with respect to a horizontal line.

6. The image reading device according to any one of claims 1 to 5, wherein: A nip width of the second conveying roller pair is wider than a width of the medium in the width direction.

7. The image reading device according to claim 6, wherein The second transport roller pair sandwiches at least a central portion and both end portions of the medium in the width direction.

8. The image reading device according to any one of claims 1 to 5, wherein: The reading unit includes: a first reading unit configured to read an image on a first side of the medium; The second reading unit is arranged to face the first reading unit and reads an image on a second surface of the medium opposite to the first surface.

Images