Media transport device

Abstract

Provided is a media conveyance device whereby jamming of media can be suppressed. This media conveyance device has: a feed roller for feeding media; a separation roller disposed facing the feed roller; a first conveyance roller disposed on a downstream side of the feed roller in a media conveyance direction; a second conveyance roller disposed facing the first conveyance roller; a first pressing part arranged so as to intersect with a first nip part between the feed roller and the separation roller as viewed from the direction orthogonal to the media conveyance direction, the first pressing part pressing, in a first direction, the media fed in the direction orthogonal to a media conveyance path; and a second pressing part arranged on the downstream side of the first nip part in the media conveyance direction and so as to intersect with a first imaginary straight line extending the first nip part downstream in the media conveyance direction as viewed from the direction orthogonal to the media conveyance direction, the second pressing part pressing, in a second direction opposite to the first direction, the media fed in the direction orthogonal to the media conveyance path.

Description

[Technical field]

[0001] The present disclosure relates to a media handling device. [Background technology]

[0002] A media transport device such as a scanner that transports and captures multiple media while separating them is required to transport not only general PPC (Plain Paper Copier) paper but also various types of media such as thin paper. Thin paper is likely to have wrinkles or tears, and is also weak, so when thin paper is transported as a medium, it is highly likely that the medium will buckle and jam.

[0003] A media supplying device is disclosed that has a feed section that feeds out media placed on a loading table, a separation section that is placed in contact with the feed section, and a first arm that has a stiffening section that presses the media toward the feed section to bend it (see Patent Document 1).

[0004] A document transport device is disclosed that is arranged between a feed roller in a transport path and a transport roller arranged downstream of the feed roller, and has a protrusion that protrudes from the lower surface of the transport path (see Patent Document 2).

[0005] A medium feeding device is disclosed that includes a regulating section that is located downstream of the nip position between the feeding roller and the separation roller and regulates contact between the medium to be fed and the separation roller by contacting the medium from the separation roller side (see Patent Document 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6082256 [Patent Document 2] Patent No. 6081792 [Patent Document 3] JP 2019-167231 A Summary of the Invention

[0007] There is a demand for a medium transport device that can prevent the occurrence of medium jams.

[0008] The medium conveying device according to the embodiment aims to prevent the occurrence of medium jams.

[0009] A medium transport device according to one aspect of the embodiment includes a feed roller for feeding a medium, a separation roller arranged opposite the feed roller, a first transport roller arranged downstream of the feed roller in a medium transport direction, a second transport roller arranged opposite the first transport roller, a first pressing portion arranged to intersect with a first nip portion between the feed roller and the separation roller as viewed from a direction perpendicular to the medium transport direction and pressing the medium being fed in a first direction in the direction perpendicular to the medium transport path, and a second pressing portion arranged downstream of the first nip portion in the medium transport direction as viewed from a direction perpendicular to the medium transport direction. and a second pressing portion arranged so as to intersect with a first virtual straight line extending from the first nip portion downstream in the media transport direction, and pressing the medium fed in a direction perpendicular to the media transport path in a second direction opposite to the first direction, wherein the first pressing portion is arranged so as to be movable in the second direction by the medium being fed, and the second pressing portion is arranged so as not to intersect with a second virtual straight line connecting the center position of the second nip portion of the first transport roller and the second transport roller and the center position of the first nip portion when viewed from the direction perpendicular to the media transport direction, or is arranged so as not to intersect with the second virtual straight line by the medium being fed.

[0010] According to this embodiment, the medium conveying device can prevent the occurrence of medium jams.

[0011] The objects and advantages of the invention will be realized and obtained by means of the elements and combinations particularly pointed out in the claims. Both the foregoing general description and the following detailed description are exemplary and explanatory but are not restrictive of the invention as claimed. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing a medium conveying device 100 according to an embodiment. [Diagram 2] 2 is a diagram for explaining a transport path inside the medium transport device 100. FIG. [Diagram 3] 1 is a schematic diagram for explaining a first pressing member 121 and the like. FIG. [Figure 4] 1 is a schematic diagram for explaining a first pressing member 121 and the like. FIG. [Diagram 5] 13A and 13B are schematic diagrams for explaining the arrangement position. [Figure 6] 13A and 13B are schematic diagrams for explaining the second pressing member 122. FIG. [Figure 7] FIG. 13 is a schematic diagram for explaining an arrangement position. [Figure 8] 13A and 13B are schematic diagrams showing how a thin paper is fed. [Figure 9] FIG. 13 is a schematic diagram showing how thin paper is fed. [Figure 10] FIG. 13 is a schematic diagram showing how thin paper is fed. [Figure 11] FIG. 4 is a schematic diagram showing how thick paper is fed. [Figure 12] 1 is a block diagram showing a schematic configuration of a medium conveying device 100. FIG. [Figure 13] FIG. 2 is a diagram showing a schematic configuration of a storage device 140 and a processing circuit 150. [Figure 14] 10 is a flowchart illustrating an example of the operation of a medium reading process. [Figure 15] 13 is a schematic diagram for explaining another second pressing member 222. FIG. [Figure 16] 13(A) and 13(B) are schematic diagrams for explaining another second pressing member 322. FIG. [Figure 17] 10 is a flowchart showing an example of the operation of another medium reading process. [Figure 18] 13 is a schematic diagram for explaining another second pressing member 422. FIG. [Figure 19] FIG. 13 is a schematic diagram showing how thin paper is fed. [Figure 20] FIG. 13 is a schematic diagram showing how thin paper is fed. [Figure 21] FIG. 4 is a schematic diagram showing how thick paper is fed. [Figure 22] 10 is a flowchart showing an example of the operation of another medium reading process. [Figure 23] 13 is a schematic diagram for explaining another second pressing member 522. FIG. [Figure 24] 13A and 13B are schematic diagrams for explaining other first pressing members 621 and the like. [Diagram 25] FIG. 13 is a diagram showing a schematic configuration of another processing circuit 750. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, a medium conveying device, a control method, and a control program according to one aspect of the present disclosure will be described with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to the embodiments, but extends to the inventions described in the claims and their equivalents.

[0014] FIG. 1 is a perspective view showing a medium conveying device 100 configured as an image scanner. The medium conveying device 100 conveys a medium, which is an original document, and captures an image of the medium. The medium is paper, thin paper, thick paper, a card, a booklet, copying paper, an envelope, or the like. The medium conveying device 100 may be a facsimile, a copier, a multifunction printer (MFP, Multifunction Peripheral), or the like. Note that the medium being conveyed may not be an original document, but may be a print target, or the like, and the medium conveying device 100 may be a printer, or the like.

[0015] The medium transport device 100 includes a lower housing 101, an upper housing 102, a loading stand 103, an ejection stand 104, an operation device 105, and a display device 106. In Fig. 1, an arrow A1 indicates the medium transport direction, an arrow A2 indicates the width direction perpendicular to the medium transport direction, and an arrow A3 indicates the height direction perpendicular to the medium transport path. In the following, upstream refers to the upstream side of the medium transport direction A1, and downstream refers to the downstream side of the medium transport direction A1.

[0016] The lower housing 101 is an example of a first housing, and the upper housing 102 is an example of a second housing. The upper housing 102 is provided so as to be openable and closable with respect to the lower housing 101. The upper housing 102 is disposed at a position covering the top surface of the medium conveying device 100, and is rotatably engaged with the lower housing 101 by a hinge so as to be openable and closable when a medium is jammed, when the inside of the medium conveying device 100 is cleaned, and the like.

[0017] The placement stage 103 engages with the lower housing 101 and places thereon the media to be fed and transported. The ejection stage 104 engages with the upper housing 102 and places thereon the ejected media. Note that the ejection stage 104 may also engage with the lower housing 101.

[0018] The operation device 105 has an input device such as a button and an interface circuit for acquiring a signal from the input device, accepts an input operation by a user, and outputs an operation signal according to the input operation by the user. The display device 106 has a display including a liquid crystal, an organic EL (Electro-Luminescence), or the like, and an interface circuit for outputting image data to the display, and displays the image data on the display.

[0019] FIG. 2 is a diagram for explaining a transport path inside the medium transport device 100. As shown in FIG.

[0020] The transport path inside the medium transport device 100 includes a medium sensor 111, a feed roller 112, a separation roller 113, a first transport roller 114, a second transport roller 115, an imaging device 116, a first discharge roller 117, and a second discharge roller 118.

[0021] The number of each of the feed roller 112, separation roller 113, first conveyance roller 114, second conveyance roller 115, first discharge roller 117, and / or second discharge roller 118 is not limited to one, and may be more than one. In this case, the multiple feed rollers 112, separation roller 113, first conveyance roller 114, second conveyance roller 115, first discharge roller 117, and / or second discharge roller 118 are arranged at intervals in the width direction A2 perpendicular to the medium conveyance direction. In the following, an example will be described in which the feed roller 112, separation roller 113, first conveyance roller 114, second conveyance roller 115, first discharge roller 117, and / or second discharge roller 118 are arranged at intervals in the width direction A2 perpendicular to the medium conveyance direction.

[0022] The top surface of the lower housing 101 forms a lower guide 101a of the medium transport path, and the bottom surface of the upper housing 102 forms an upper guide 102a of the medium transport path.

[0023] The media sensor 111 is disposed upstream of the feed roller 112 and the separation roller 113. The media sensor 111 has a contact detection sensor, and detects whether or not a medium is placed on the placement table 103. The media sensor 111 generates and outputs a media signal whose signal value changes depending on whether or not a medium is placed on the placement table 103. Note that the media sensor 111 is not limited to a contact detection sensor, and any other sensor capable of detecting the presence or absence of a medium, such as a light detection sensor, may be used as the media sensor 111.

[0024] The feed roller 112 is provided in the lower housing 101, and separates and feeds the media placed on the mounting table 103 from the bottom. The separation roller 113 is a so-called brake roller or retard roller, and is provided in the upper housing 102, and disposed opposite the feed roller 112. The separation roller 113 is provided so as to be rotatable or stoppable in the direction opposite to the medium feeding direction. Note that the feed roller 112 may be provided in the upper housing 102 and the separation roller 113 in the lower housing 101, and the feed roller 112 may feed the media placed on the mounting table 103 from the top.

[0025] The first conveying roller 114 and the second conveying roller 115 are disposed opposite each other downstream of the feed roller 112 and the separation roller 113 in the medium conveying direction A1. The first conveying roller 114 is provided in the upper housing 102, and conveys the medium fed by the feed roller 112 and the separation roller 113 to the imaging device 116.

[0026] The imaging device 116 is an example of an imaging section, and is disposed downstream of the first transport roller 114 and the second transport roller 115 in the medium transport direction A1, and captures an image of the medium transported by the first transport roller 114 and the second transport roller 115. The imaging device 116 includes a first imaging device 116a and a second imaging device 116b disposed opposite each other across the medium transport path.

[0027] The first imaging device 116a has a line sensor using a CIS (Contact Image Sensor) of a life-size optical system type having imaging elements using CMOS (Complementary Metal Oxide Semiconductor) linearly arranged in the main scanning direction. The first imaging device 116a also has a lens that forms an image on the imaging elements, and an A / D converter that amplifies and analog-to-digital (A / D) converts the electrical signal output from the imaging elements. The first imaging device 116a captures the surface of the medium being conveyed under the control of a processing circuit described later, generates an input image, and outputs it.

[0028] Similarly, the second imaging device 116b has a line sensor using a CIS of a life-size optical system type having CMOS imaging elements arranged in a line in the main scanning direction. The second imaging device 116b also has a lens that forms an image on the imaging element, and an A / D converter that amplifies and analog-to-digital (A / D) converts the electrical signal output from the imaging element. The second imaging device 116b captures the back side of the medium being conveyed under the control of a processing circuit described later, generates an input image, and outputs it.

[0029] The medium conveying device 100 may have only one of the first imaging device 116a and the second imaging device 116b arranged to read only one side of the medium. Also, instead of a CIS line sensor of an equal magnification optical system type having a CMOS imaging element, a CIS line sensor of an equal magnification optical system type having a CCD (Charge Coupled Device) imaging element may be used. Also, a reduction optical system type line sensor having a CMOS or CCD imaging element may be used.

[0030] The first discharge roller 117 and the second discharge roller 118 are disposed opposite each other in the medium conveying direction A1 from the imaging device 116, i.e., downstream from the first conveying roller 114 and the second conveying roller 115. The first discharge roller 117 is provided in the upper housing 102, and conveys the medium conveyed by the first conveying roller 114 and the second conveying roller 115 further downstream and discharges it onto the discharge tray 104.

[0031] The medium placed on the placement table 103 is conveyed between the lower guide 101a and the upper guide 102a in the medium conveying direction A1 by the rotation of the feed roller 112 in the direction of the arrow A4, i.e., the medium feeding direction. The medium conveying device 100 has a separation mode in which the medium is separated while being fed, and a non-separation mode in which the medium is fed without being separated, as the feeding mode. The feeding mode is set by the user using the operation device 105 or an information processing device that is communicatively connected to the medium conveying device 100. When the feeding mode is set to the separation mode, the separation roller 113 rotates or stops in the direction of the arrow A5, i.e., the opposite direction to the medium feeding direction. When multiple media are placed on the placement table 103, only the media in contact with the feed roller 112 among the media placed on the placement table 103 is separated by the action of the feed roller 112 and the separation roller 113. This limits the conveyance of media other than the separated media (prevention of double feeding). On the other hand, when the feeding mode is set to the non-separation mode, the separation roller 113 rotates in the direction opposite to the arrow A5, that is, in the medium feeding direction.

[0032] The medium is fed between the first conveyor roller 114 and the second conveyor roller 115 while being guided by the lower guide 101a and the upper guide 102a. The medium is fed between the first imaging device 116a and the second imaging device 116b as the first conveyor roller 114 and the second conveyor roller 115 rotate in the directions of the arrows A6 and A7, respectively. The medium read by the imaging device 116 is discharged onto the discharge tray 104 as the first discharge roller 117 and the second discharge roller 118 rotate in the directions of the arrows A8 and A9.

[0033] 3 and 4 are schematic diagrams for explaining the first pressing member 121 and the second pressing member 122. Fig. 3 is a cross-sectional view (perspective view) of the periphery of the feed roller 112 and the separation roller 113 cut at the center position in the width direction A2 by a plane perpendicular to the width direction A2. Fig. 4 is a side view of the cross-sectional view of Fig. 3 seen from the side.

[0034] As shown in FIGS. 3 and 4, the medium conveying device 100 further includes a first pressing member 121 and a second pressing member 122.

[0035] The first pressing member 121 is an example of a first pressing portion. The first pressing member 121 is disposed in the upper housing 102, and is provided so as to protrude downward from a first nip portion N1 between the feed roller 112 and the separation roller 113 in the height direction A3. The first nip portion N1 is a flat area formed by the surface of the feed roller 112 and the surface of the separation roller 113 which press against each other, and has a width of about 4 mm or more and 8 mm or less in the medium conveying direction A1. The first pressing member 121 includes a rotating shaft 121a, an arm 121b, and a spring 121c.

[0036] The rotating shaft 121a is provided on the upper housing 102 so as to extend in the width direction A2 and be rotatable. The arm 121b is a plate-like member provided so as to extend toward the upstream side in the medium transport direction A1. The downstream end of the arm 121b is attached to the rotating shaft 121a, and the arm 121b is provided so as to be swingable (rotatable) around the rotating shaft 121a. The spring 121c is a torsion coil spring or the like, and is provided on the rotating shaft 121a so as to apply a force in the direction of the arrow A11 (a force directed downward in the height direction A3) to the arm 121b. The arm 121b, biased by the spring 121c in the direction of the arrow A11, is disposed in an initial position in contact with the stopper 121d. In the initial position, the lower end of the arm 121b is disposed below the first nip portion N1.

[0037] That is, the first pressing member 121 is disposed so as to intersect with the first nip portion N1 between the feed roller 112 and the separation roller 113 when viewed from the width direction A2 perpendicular to the medium transport direction. The first pressing member 121 is also provided so as to be movable upward in the height direction A3.

[0038] The second pressing member 122 is an example of a second pressing portion. The second pressing member 122 is a resin member, and is disposed in the lower housing 101, and is provided so as to protrude upward from the first nip portion N1 between the feed roller 112 and the separation roller 113 in the height direction A3. That is, the upper end of the second pressing member 122 is disposed above the first nip portion N1. The second pressing member 122 is formed integrally with the lower housing 101. The second pressing member 122 may be formed of a member separate from the lower housing 101. The second pressing member 122 is disposed downstream of the first nip portion N1 in the medium conveying direction A1, that is, downstream of a portion of the first pressing member 121 that intersects with the first nip portion N1.

[0039] 5(A) and (B) are schematic diagrams for explaining the positions of the first pressing member 121 and the second pressing member 122 in the width direction A2. Fig. 5(A) is a schematic diagram of the periphery of the feed roller 112 and the separation roller 113 as viewed from the upstream side, and Fig. 5(B) is a schematic diagram of the periphery of the feed roller 112 and the separation roller 113 as viewed from the downstream side.

[0040] 5(A) and (B), in the width direction A2 perpendicular to the medium transport direction, the first pressing member 121 and the second pressing member 122 are disposed between the two feed rollers 112 and between the two separation rollers 113. By disposing the first pressing member 121 and the second pressing member 122 at the center in the width direction A2, the medium transport device 100 can equalize the force applied to both sides of the fed medium in the width direction A2, thereby suppressing the occurrence of skew of the medium.

[0041] 6(A) and (B) are schematic diagrams for explaining the second pressing member 122. Fig. 6(A) is a perspective view of the lower guide 101a from above with the feed roller 112 removed. Fig. 6(B) is a cross-sectional view (perspective view) of the lower guide 101a from which the feed roller 112 is removed, cut along a plane that is perpendicular to the width direction A2 and passes between the two feed rollers 112.

[0042] As shown in FIGS. 6A and 6B, the second pressing member 122 is provided in the opening 101b in the lower guide 101a where the feed roller 112 is disposed. The second pressing member 122 is provided in the center of the opening 101b in the width direction A2 so as to extend from the downstream end of the opening 101b in the medium conveying direction A1 to the upstream side. The lower guide 101a is provided with an extension portion 101c extending from the upstream end of the opening 101b in the medium conveying direction A1 to the downstream side in the center of the opening 101b in the width direction A2. The second pressing member 122 is provided so that the upstream end of the second pressing member 122 is separated from the downstream end of the extension portion 101c. In addition, a slit 101d extending in the medium conveying direction A1 is provided between the second pressing member 122 and the end of the lower guide 101a facing the upstream end of the opening 101b. As a result, the second pressing member 122 is provided so as to bend in the direction of the arrow A12 (downward in the height direction A3).

[0043] Fig. 7 is a schematic diagram for explaining the arrangement position in the medium transport direction A1 and the height direction A3 of the second pressing member 122. Fig. 7 is a schematic diagram of the periphery of the feed roller 112, the separation roller 113, the first transport roller 114, and the second transport roller 115 as viewed from the side.

[0044] 7, the upper end of the second pressing member 122 is disposed above a first virtual straight line L1 that extends the first nip portion N1 between the feed roller 112 and the separation roller 113 downstream in the medium transport direction A1. That is, the second pressing member 122 is disposed so as to intersect with the first virtual straight line L1 that extends the first nip portion N1 downstream in the medium transport direction A1 when viewed from the width direction A2 perpendicular to the medium transport direction.

[0045] On the other hand, the upper end of the second pressing member 122 is disposed below a second imaginary straight line L2 connecting the center position C1 of the first nip portion N1 between the feed roller 112 and the separation roller 113 and the center position C2 of the second nip portion N2 between the first conveying roller 114 and the second conveying roller 115. That is, the second pressing member 122 is disposed so as not to intersect with the second imaginary straight line L2 connecting the center position C1 of the first nip portion N1 and the center position C2 of the second nip portion N2 when viewed from the width direction A2 perpendicular to the medium conveying direction. The second nip portion N2 is a flat area formed by the surface of the first conveying roller 114 and the surface of the second conveying roller 115 pressing against each other, and has a width of about 4 mm or more and 8 mm or less in the medium conveying direction A1. The center position C1 of the first nip N1 is the intersection of the first nip N1 and a straight line connecting the rotation center C3 of the feed roller 112 and the rotation center C4 of the separation roller 113. The center position C2 of the second nip N2 is the intersection of the second nip N2 and a straight line connecting the rotation center C5 of the first conveyor roller 114 and the rotation center C6 of the second conveyor roller 115.

[0046] Figures 8(A), (B), 9, and 10 are schematic diagrams showing how thin paper is fed as medium M1. Figures 8(A), (B), and 9 show the state where the leading edge of medium M1 has passed through the first nip portion N1, and Figure 10 shows the state where the leading edge of medium M1 has passed through the second nip portion N2.

[0047] As shown in Figures 8(A) and 9, the first pressing member 121 presses the fed medium M1 downward in a height direction A3 perpendicular to the medium transport path. The downward direction in the height direction A3 is an example of the first direction. As shown in Figure 8(A), the first pressing member 121 presses the center of the medium M1 downward in the width direction A2. Also, as shown in Figure 9, the first pressing member 121 presses the medium M1 downward at the first nip portion N1.

[0048] As a result, the fed medium M1 bends in a wavy manner in the width direction A2 at the first nip N1 where the medium is separated. Therefore, the medium conveying device 100 can stiffen the medium along the medium conveying direction A1 when separating the medium, thereby improving the rigidity of the medium traveling in the medium conveying direction A1. Therefore, even when thin paper with low stiffness is conveyed as the medium, the medium conveying device 100 can suppress the occurrence of buckling of the medium and suppress the occurrence of medium jams.

[0049] The first pressing member 121 is disposed on the upper side in the height direction A3 perpendicular to the medium transport path, and presses the fed medium downward. This allows the medium transport device 100 to apply an appropriate force to the fed medium by utilizing the gravity of the first pressing member 121 at the first nip portion N1 where the medium is separated, thereby stiffening the medium.

[0050] As shown in Figures 8(B) and 9, the second pressing member 122 presses the fed medium M1 upward in a height direction A3 perpendicular to the medium transport path. The upward direction in the height direction A3 is an example of a second direction opposite to the first direction. As shown in Figure 8(B), the second pressing member 122 presses the center of the medium M1 upward in the width direction A2. As shown in Figure 9, the second pressing member 122 presses the medium M1 upward downstream of the first nip portion N1.

[0051] As a result, the fed medium M1 bends in a wavy manner in the width direction A2 even after passing through the feed roller 112 and the separation roller 113. Therefore, the medium conveying device 100 can stiffen the medium along the medium conveying direction A1 even after the medium is separated, and can improve the rigidity of the medium traveling in the medium conveying direction A1. Furthermore, the medium conveying device 100 can stiffen the medium along the width direction A2 by the first pressing member 121 and the second pressing member 122, and can improve the rigidity of the medium. Therefore, even when thin paper with low stiffness is conveyed as the medium, the medium conveying device 100 can suppress the occurrence of buckling of the medium and suppress the occurrence of a medium jam.

[0052] The second pressing member 122 is disposed on the lower side in the height direction A3 perpendicular to the medium transport path, and presses the fed medium upward. This prevents the leading edge of the medium M1 pressed downward by the first pressing member 121 from contacting the lower guide 101a, thereby preventing a reduction in the transport force of the medium M1. It also prevents the leading edge of the medium M1 from contacting the lower guide 101a due to static electricity between the fed medium and the surface of the feed roller 112, thereby preventing a reduction in the transport force of the medium M1.

[0053] Generally, the lower guide 101a is formed of different materials around the feed roller 112 and around the second conveyor roller 115, and a step T is formed between the feed roller 112 and the second conveyor roller 115 on the lower guide 101a. The second pressing member 122 presses the leading edge of the medium that has passed through the feed roller 112 and the separation roller 113 upward, thereby preventing the leading edge of the medium from contacting the step T formed between the feed roller 112 and the second conveyor roller 115 on the lower guide 101a. This allows the medium conveying device 100 to prevent the leading edge of the medium M1 from colliding with the step T and causing buckling of the medium M1.

[0054] As described above, the arm 121b of the first pressing member 121 is provided so as to be able to swing, and is biased downward by the spring 121c. As shown in FIG. 10, when the leading edge of the medium M1 passes through the second nip portion N2, the medium M1 is pulled by the first nip portion N1 and the second nip portion N2 to generate sufficient rigidity. In this case, in the arm 121b, the upward force applied by the rigidity of the medium M1 being fed exceeds the downward force applied by the spring 121c, and the first pressing member 121 is pushed upward and placed at the moving position shown in FIG. 10. In this way, the first pressing member 121 is provided so as to be able to move upward in the height direction A3 by the medium M1 being fed. As a result, after the leading edge of the medium M1 passes through the first conveying roller 114 and the second conveying roller 115, the medium M1 is not bent downward by the first pressing member 121.

[0055] Furthermore, as described above, the second pressing member 122 is disposed so as not to intersect with the second virtual straight line L2 connecting the center position C1 of the first nip portion N1 and the center position C2 of the second nip portion N2. As shown in Fig. 10, when the leading edge of the medium M1 passes through the second nip portion N2, the medium M1 is disposed so as to be pulled by the first nip portion N1 and the second nip portion N2 and extend along the second virtual straight line L2. As a result, after the leading edge of the medium M1 passes through the first conveyor roller 114 and the second conveyor roller 115, the second pressing member 122 does not come into contact with the medium M1.

[0056] Therefore, after the leading edge of medium M1 passes through first conveyor roller 114 and second conveyor roller 115, medium M1 is not bent in a wavy manner in width direction A2 by first pressing member 121 and second pressing member 122. As a result, the input image generated by imaging device 116 arranged downstream of first conveyor roller 114 and second conveyor roller 115 does not include wrinkles due to bending of the medium, and medium conveyor device 100 can obtain a good input image.

[0057] FIG. 11 is a schematic diagram showing how thick paper is fed as the medium M2.

[0058] As described above, the first pressing member 121 is provided so as to be movable upward in the height direction A3 by the medium being fed. When thick paper is fed as the medium M2, the upward force applied to the arm 121b by the rigidity of the medium M2 being fed exceeds the downward force applied by the spring 121c, and the first pressing member 121 is pushed upward and placed at the moving position. This prevents the first pressing member 121 from applying excessive force to the medium, causing the medium to bend, when thick paper is fed as the medium.

[0059] As described above, the second pressing member 122 is arranged to bend downward. When thick paper is fed as the medium M2, the second pressing member 122 is pressed downward due to the rigidity of the fed medium M2, and is disposed at the movement position shown in Fig. 11. This prevents the medium from being bent due to excessive force being applied to the medium by the second pressing member 122 when thick paper is fed as the medium.

[0060] The first pressing member 121 and / or the second pressing member 122 are provided so as to move when PPC paper is fed as the medium in the same manner as when thick paper is fed. Alternatively, the first pressing member 121 and / or the second pressing member 122 may be provided so as to move or stop when PPC paper is fed as the medium in the same manner as when thin paper is fed.

[0061] FIG. 12 is a block diagram showing a schematic configuration of the medium conveying device 100. As shown in FIG.

[0062] In addition to the components described above, the medium conveying device 100 further includes a motor 131, an interface device 132, a storage device 140, a processing circuit 150, and the like.

[0063] The motor 131 has one or more motors, and rotates the feed roller 112, separation roller 113, first conveyance roller 114, second conveyance roller 115, first discharge roller 117, and / or second discharge roller 118 to convey the medium in response to a control signal from the processing circuit 150. Each motor is, for example, a DC (Direct Current) motor. Each motor may be a stepping motor. Also, one of the first conveyance roller 114 and the second conveyance roller 115 may be a driven roller that rotates following the other roller. Also, one of the first discharge roller 117 and the second discharge roller 118 may be a driven roller that rotates following the other roller.

[0064] The interface device 132 has an interface circuit conforming to a serial bus such as USB, and is electrically connected to an information processing device (not shown, for example, a personal computer, a mobile information terminal, etc.) to transmit and receive input images and various information. Also, instead of the interface device 132, a communication unit having an antenna for transmitting and receiving wireless signals and a wireless communication interface device for transmitting and receiving signals through a wireless communication line in accordance with a predetermined communication protocol may be used. The predetermined communication protocol is, for example, a wireless LAN (Local Area Network). The communication unit may have a wired communication interface device for transmitting and receiving signals through a wired communication line in accordance with a communication protocol such as a wired LAN.

[0065] The storage device 140 includes a memory device such as a random access memory (RAM) or a read only memory (ROM), a fixed disk device such as a hard disk, or a portable storage device such as a flexible disk or an optical disk. The storage device 140 also stores computer programs, databases, tables, and the like used for various processes of the medium conveying device 100. The computer programs may be installed in the storage device 140 from a computer-readable portable recording medium using a known setup program or the like. The portable recording medium is, for example, a compact disc read only memory (CD-ROM), a digital versatile disc read only memory (DVD-ROM), or the like.

[0066] The processing circuit 150 operates based on a program previously stored in the storage device 140. The processing circuit is, for example, a CPU (Central Processing Unit). The processing circuit 150 may be, for example, a DSP (digital signal processor), an LSI (large scale integration), an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable Gate Array).

[0067] The processing circuit 150 is connected to the operation device 105, the display device 106, the medium sensor 111, the imaging device 116, the motor 131, the interface device 132, the storage device 140, etc., and controls each of these components. The processing circuit 150 performs drive control of the motor 131, imaging control of the imaging device 116, etc., based on a medium signal received from the medium sensor 111. The processing circuit 150 acquires an input image from the imaging device 116, and transmits it to the information processing device via the interface device 132.

[0068] FIG. 13 is a diagram showing a schematic configuration of the storage device 140 and the processing circuit 150. As shown in FIG.

[0069] 13, the storage device 140 stores a control program 141, an abnormality detection program 142, a movement detection program 143, and the like. Each of these programs is a functional module implemented by software that runs on a processor. The processing circuit 150 reads each program stored in the storage device 140 and operates according to the read program. In this way, the processing circuit 150 functions as a control unit 151, an abnormality detection unit 152, and a movement detection unit 153.

[0070] FIG. 14 is a flowchart showing an example of the operation of the medium reading process of the medium conveying device 100.

[0071] An example of the operation of the medium reading process of the medium conveying device 100 will be described below with reference to the flowchart shown in Fig. 14. Note that the flow of the operation described below is executed mainly by the processing circuit 150 in cooperation with each element of the medium conveying device 100 based on a program stored in advance in the storage device 140.

[0072] First, the control unit 151 waits until a user inputs an instruction to read a medium using the operation device 105 or an information processing device, and an operation signal instructing the user to read a medium is received from the operation device 105 or the interface device 132 (step S101).

[0073] Next, control unit 151 acquires a medium signal from medium sensor 111, and determines whether or not a medium is placed on mounting table 103 based on the acquired medium signal (step S102). If no medium is placed on mounting table 103, control unit 151 ends the series of steps.

[0074] On the other hand, when a medium is placed on the placement table 103, the control unit 151 rotates the feeding roller 112, the separation roller 113, the first conveying roller 114, the second conveying roller 115, the first discharge roller 117 and / or the second discharge roller 118 (step S103). The control unit 151 drives the motor 131 to rotate each roller to feed and convey the medium.

[0075] Next, the control unit 151 determines whether the entire medium has been imaged (step S104). The control unit 151, for example, is disposed upstream of the imaging device 116 and determines whether the rear end of the medium has passed the position of the media sensor based on a detection signal received from a media sensor (not shown) that detects the presence of the medium. The control unit 151 determines that the rear end of the medium has passed the position of the media sensor when the signal value of the detection signal received from the media sensor changes from a value indicating the presence of the medium to a value indicating the absence of the medium. The control unit 151 determines that the rear end of the medium has passed the imaging position of the imaging device 116 and the entire medium has been imaged when a predetermined time has elapsed since the rear end of the medium passed the position of the media sensor. Note that the control unit 151 may determine that the entire transported medium has been imaged when a predetermined time has elapsed since the start of feeding the medium. The control unit 151 waits until the entire medium has been imaged.

[0076] When the entire medium has been imaged, the control unit 151 acquires an input image from the imaging device 116, and outputs the acquired input image by transmitting it to the information processing device via the interface device 132 (step S105).

[0077] Next, control unit 151 determines whether or not a medium remains on mounting table 103 based on the medium signal received from medium sensor 111 (step S106). If a medium remains on mounting table 103, control unit 151 returns the process to step S104, and repeats the processes of steps S104 to S106.

[0078] On the other hand, if no media remain on the placement table 103, the control unit 151 stops the feed roller 112, the separation roller 113, the first conveyor roller 114, the second conveyor roller 115, the first discharge roller 117 and / or the second discharge roller 118 (step S107). The control unit 151 controls the motor 131 to stop each roller, and ends the series of steps.

[0079] As described above in detail, the medium conveying device 100 has the first pressing member 121 that presses the medium at the first nip portion N1 between the feed roller 112 and the separation roller 113. The medium conveying device 100 also has the second pressing member 122 that presses the medium from the opposite side to the first pressing member 121 downstream of the first nip portion N1. This enables the medium conveying device 100 to stiffen the medium both in the medium conveying direction A1 and the width direction A2, making it possible to prevent the occurrence of medium jams.

[0080] In particular, the medium conveying device 100 can suppress the occurrence of medium jams even when various types of media such as thin paper, PPC paper, and thick paper are conveyed, when wrinkled or torn media are conveyed, or when a large amount of media is conveyed. Therefore, the medium conveying device 100 can suppress damage to each medium being conveyed. In addition, since the frequency with which the user re-conveys media is reduced, the medium conveying device 100 can improve the user's work efficiency and improve the user's convenience.

[0081] In a medium transport device that does not have a first pressing member and a second pressing member, 2 As a result of an experiment in which thin paper of A7 size was conveyed, the probability of jamming was 3.0%, of which the probability of jamming at the first nip between the feeding roller and the separation roller was 2.0%, and the probability of jamming between the first nip and the second nip between the first conveying roller and the second conveying roller was 1.0%.

[0082] In addition, an experiment was conducted to transport the thin paper in a medium transport device having a first pressing member but not a second pressing member, and the result was that the probability of jamming was 1.0%. Of that, the probability of jamming at the first nip was 0.2%, and the probability of jamming between the first nip and the second nip was 0.8%. In addition, an experiment was conducted to transport the thin paper in a medium transport device having a second pressing member but not a first pressing member, and the result was that the probability of jamming was 2.5%. Of that, the probability of jamming at the first nip was 2.0%, and the probability of jamming between the first nip and the second nip was 0.5%.

[0083] Meanwhile, in an experiment conducted on conveying the above-mentioned thin paper in the medium conveying device 100 having the first pressing member 121 and the second pressing member 122, the probability of jamming was 0.3%. Of these, the probability of jamming at the first nip was 0.2%, and the probability of jamming between the first nip and the second nip was 0.1%. Thus, by having both the first pressing member 121 and the second pressing member 122, the medium conveying device 100 is able to dramatically reduce the occurrence of jamming of thin paper.

[0084] FIG. 15 is a schematic diagram for explaining a second pressing member 222 in a medium conveying device according to another embodiment.

[0085] The second pressing member 222 shown in FIG. 15 is used in place of the second pressing member 122 of the medium conveying device 100. The second pressing member 222 has a similar configuration to the second pressing member 122. However, a roller 223 that comes into contact with the medium being fed and rotates with the movement of the medium is disposed at the tip (upper end) of the second pressing member 222. This allows the medium being fed to move smoothly toward the downstream side, allowing the medium conveying device to feed the medium better. Note that the roller 223 may not be directly attached to the second pressing member 222, but may be attached to the second pressing member 222 via a spring member such as a compression coil spring or a leaf spring, or an elastic member such as a rubber member.

[0086] As described above in detail, the medium conveying device can prevent the occurrence of medium jams even when the rollers 223 are provided on the second pressing member 222.

[0087] 16A and 16B are schematic diagrams for explaining a second pressing member 322 in a medium conveying device according to yet another embodiment.

[0088] 16(A) and (B) is used in place of the second pressing member 122 of the medium conveying device 100. The second pressing member 322 has a configuration similar to that of the second pressing member 122. However, an encoder 323 is disposed at the tip (upper end) of the second pressing member 322, and is rotatable in accordance with the medium being fed.

[0089] The encoder 323 includes a roller 323a, a case 323b, a disk 323c, a light emitter 323d, and a light receiver 323e. The roller 323a is provided so as to come into contact with the medium being fed and rotate with the movement of the medium. A group of gears is provided inside the case 323b so as to rotate with the rotation of the roller 323a and rotate the disk 323c. A large number of slits (light transmitting holes) are formed in the disk 323c. The light emitter 323d and the light receiver 323e are provided so as to face each other across the disk 323c. The light receiver 323e calculates the number of times that the state where there is a slit between the light emitter 323d and the light receiver 323e changes to the state where there is no slit and the light is blocked by the disk 323c at regular intervals. The light receiver 323e calculates the moving speed of the outer circumferential surface of the roller 323a, ie, the moving speed of the medium being fed, based on the calculated number of changes, and generates and outputs a moving speed signal indicating the calculated moving speed.

[0090] FIG. 17 is a flowchart showing an example of the operation of a medium reading process of the medium conveying device according to the present embodiment.

[0091] An example of the operation of the medium reading process of the medium conveying device according to this embodiment will be described below with reference to the flowchart shown in Fig. 17. The flow of the operation described below is executed mainly by the processing circuit 150 in cooperation with each element of the medium conveying device based on a program previously stored in the storage device 140. The flow of the operation shown in Fig. 17 is executed instead of the flowchart shown in Fig. 14. Note that the processes of steps S201 to S203 and S208 to S210 are the same as the processes of steps S101 to S103 and S105 to S107 in Fig. 14, so their explanations are omitted, and only the processes of steps S204 to S207 will be described below.

[0092] In step S204, the abnormality detection unit 152 acquires a moving speed signal from the encoder 323 (step S204).

[0093] Next, the abnormality detection unit 152 determines whether or not a medium feeding abnormality has occurred based on the acquired moving speed signal, i.e., based on the rotation of the encoder 323 (step S205). If the moving speed indicated by the moving speed signal is equal to or greater than the speed threshold, the abnormality detection unit 152 determines that a medium feeding abnormality has not occurred. On the other hand, if the moving speed indicated by the moving speed signal is less than the speed threshold, the abnormality detection unit 152 determines that the medium is not progressing and a medium jam has occurred, and determines that a medium feeding abnormality has occurred. The speed threshold is set to a value obtained by subtracting a margin from the moving speed of the outer circumferential surface of the feed roller 112 caused by the motor 131.

[0094] If the abnormality detection unit 152 determines that a medium feeding abnormality has occurred, the control unit 151 executes abnormality processing (step S206) and ends the series of steps. As abnormality processing, the control unit 151 stops the motor 131 to stop feeding and transporting the medium. This allows the medium transport device to prevent damage to the medium. As abnormality processing, the control unit 151 may also notify the user by displaying information indicating that a medium feeding abnormality has occurred on the display device 106 or by transmitting the information to the information processing device via the interface device 132.

[0095] On the other hand, if abnormality detection unit 152 has not determined that a medium feeding abnormality has occurred, control unit 151 determines whether or not the entire medium has been imaged (step S207) in the same manner as in the process of step S104. If the entire medium has not yet been imaged, control unit 151 returns the process to step S204 and repeats the processes of steps S204 to S207. On the other hand, if the entire medium has been imaged, control unit 151 proceeds to the process of step S208.

[0096] As described above in detail, the medium conveying device can prevent the occurrence of medium jams even when the encoder 323 is provided on the second pressing member 322.

[0097] Fig. 18 is a schematic diagram for explaining a second pressing member 422 in a medium conveying device according to still another embodiment. Fig. 18 is a cross-sectional view (perspective view) of the periphery of the feed roller 112 and the separation roller 113 cut at the center position in the width direction A2 by a plane perpendicular to the width direction A2.

[0098] 18 is used in place of the second pressing member 122 of the medium conveying device 100. The second pressing member 422 has a similar configuration to the second pressing member 122. However, the second pressing member 422 is provided so as to be movable by the medium being fed.

[0099] The second pressing member 422 includes a rotating shaft 422a, an arm 422b, and a spring 422c. The rotating shaft 422a is provided on the lower housing 101 so as to extend in the width direction A2 and be rotatable. The arm 422b is a plate-shaped member provided so as to extend toward the upstream side in the medium transport direction A1. The downstream end of the arm 422b is attached to the rotating shaft 422a, and the arm 422b is provided so as to be swingable (rotatable) around the rotating shaft 422a. The spring 422c is a torsion coil spring or the like, and is provided on the rotating shaft 422a so as to apply a force in the direction of the arrow A13 (a force directed upward in the height direction A3) to the arm 422b. The arm 422b, biased by the spring 422c in the direction of the arrow A13, is disposed in an initial position where it abuts against the stopper 422d. In this manner, the second pressing member 422 is provided so as to be movable downward in the height direction A3.

[0100] Figures 19 and 20 are schematic diagrams showing how thin paper is fed as medium M3. Figure 19 shows a state in which the leading edge of medium M3 has passed through the first nip portion N1, and Figure 20 shows a state in which the leading edge of medium M3 has passed through the second nip portion N2. In Figure 19, the second pressing member 422 is disposed in the initial position, and in Figure 20, the second pressing member 422 is pressed downward by medium M3 and disposed in the first movement position.

[0101] 19 and 20, the upper end of the second pressing member 122 is disposed above a first imaginary straight line L1 that extends the first nip portion N1 between the feed roller 112 and the separation roller 113 downstream in the medium conveying direction A1 in both the initial position and the first moving position. That is, the second pressing member 122 is disposed so as to intersect with the first imaginary straight line L1 that extends the first nip portion N1 downstream in the medium conveying direction A1 when viewed from the width direction A2 perpendicular to the medium conveying direction. In this manner, the second pressing member 422 is disposed in the lower housing 101 and provided so as to protrude upward from the first nip portion N1 between the feed roller 112 and the separation roller 113 in the height direction A3.

[0102] 19, the upper end of the second pressing member 122 in the initial position is disposed above a second imaginary straight line L2 that connects the center position C1 of the first nip portion N1 and the center position C2 of the second nip portion N2 between the first conveying roller 114 and the second conveying roller 115. That is, the second pressing member 122 is disposed so as to intersect with the second imaginary straight line L2 that connects the center position C1 of the first nip portion N1 and the center position C2 of the second nip portion N2 in the initial position when viewed from the width direction A2 perpendicular to the medium conveying direction.

[0103] When thin paper is fed as medium M3, the second pressing member 422 is disposed in an initial position, similar to the second pressing member 122, and presses the fed medium M3 upward in the height direction A3 perpendicular to the medium transport path. The second pressing member 422 presses the medium M3 upward downstream of the first nip portion N1.

[0104] As a result, the fed medium M3 bends in a wavy manner in the width direction A2 even after passing through the feed roller 112 and the separation roller 113. Therefore, the medium conveying device can stiffen the medium along the medium conveying direction A1 even after the medium is separated, and can improve the rigidity of the medium traveling in the medium conveying direction A1. Therefore, even when thin paper with low stiffness is conveyed as the medium, the medium conveying device can suppress the occurrence of buckling of the medium and suppress the occurrence of a medium jam. In particular, since the upper end of the second pressing member 422 is positioned above the second virtual straight line L2, the medium can be stiffened more strongly, and the rigidity of the medium traveling in the medium conveying direction A1 can be further improved.

[0105] As described above, the arm 422b of the second pressing member 422 is provided to be able to swing, and is biased upward by the spring 422c. As shown in FIG. 20, when the leading end of the medium M3 passes through the second nip portion N2, the medium M3 is pulled by the first nip portion N1 and the second nip portion N2 to generate sufficient rigidity. At this time, the medium M3 is arranged so as to be pulled by the first nip portion N1 and the second nip portion N2 and extend along the second virtual straight line L2. In this case, the downward force applied by the rigidity of the fed medium M3 in the arm 422b exceeds the upward force applied by the spring 422c, and the second pressing member 422 is pressed downward and arranged at the first movement position. In the first movement position, the upper end of the second pressing member 422 is disposed below a second imaginary straight line L2 that connects the center position C1 of the first nip portion N1 and the center position C2 of the second nip portion N2 between the first conveying roller 114 and the second conveying roller 115. In other words, the second pressing member 122 is movably provided at a position that does not intersect with the second imaginary straight line L2 that connects the center position C1 of the first nip portion N1 and the center position C2 of the second nip portion N2 when viewed from the width direction A2 perpendicular to the medium conveying direction.

[0106] In this manner, the second pressing member 422 is provided so as to be movable downward in the height direction A3 by the medium M3 being fed. As a result, after the leading end of the medium M3 has passed through the first conveyor roller 114 and the second conveyor roller 115, the leading end of the medium M3 is not bent upward by the second pressing member 422.

[0107] Therefore, after the leading edge of medium M3 passes through first conveyor roller 114 and second conveyor roller 115, medium M3 is not bent in a wavy manner in width direction A2 by first pressing member 121 and second pressing member 422. As a result, an input image generated by imaging device 116 disposed downstream of first conveyor roller 114 and second conveyor roller 115 does not include shading (noise) due to bending of the medium, and the medium conveyor device can obtain a good input image.

[0108] FIG. 21 is a schematic diagram showing how thick paper is fed as medium M4.

[0109] As described above, the second pressing member 422 is provided so as to be movable downward in the height direction A3 by the medium being fed. When thick paper is fed as the medium M4, the downward force applied to the arm 422b by the rigidity of the medium M4 being fed exceeds the upward force applied by the spring 422c. Therefore, the second pressing member 422 is pressed downward and disposed at the second movement position further below the first movement position. This prevents the first pressing member 121 from applying excessive force to the medium and bending the medium when thick paper is fed as the medium.

[0110] The second pressing member 422 is provided so as to move when PPC paper is fed as the medium in the same manner as when thick paper is fed. Alternatively, the second pressing member 422 may be provided so as to move or stop when PPC paper is fed as the medium in the same manner as when thin paper is fed.

[0111] As shown in FIG. 19, FIG. 20, and FIG. 21, the medium conveying device according to this embodiment further includes a movement sensor 423. The movement sensor 423 includes a light emitter and a light receiver that are provided to face each other. The light emitter and the light receiver are provided so as not to face the tip of the arm 422b when the second pressing member 422 is disposed at the initial position or the first movement position, and are provided so as to face the tip of the arm 422b when the second pressing member 422 is disposed at the second movement position. The light emitter is an LED (Light Emitting Diode) or the like, and emits light toward the light receiver. On the other hand, the light receiver is a photodiode or the like, and receives the light emitted by the light emitter. When the second pressing member 422 is disposed at the initial position or the first movement position, the light receiver detects the light emitted from the light emitter. On the other hand, when the second pressing member 422 is disposed at the second movement position, the light emitted from the light emitter is blocked by the tip of the arm 422b, and the light receiver does not detect the light emitted from the light emitter. The movement sensor 423 generates and outputs a movement detection signal whose signal value changes depending on whether the arm 422b is present or not at the position of the movement sensor 423, based on the intensity of the light received by the light receiver. The movement detection signal indicates whether the second pressing member 422 is disposed at the second movement position, i.e., whether the medium being fed is cardboard or not.

[0112] FIG. 22 is a flowchart showing an example of the operation of a medium reading process of the medium conveying device according to the present embodiment.

[0113] An example of the operation of the medium reading process of the medium conveying device according to this embodiment will be described below with reference to the flowchart shown in Fig. 22. The flow of the operation described below is executed mainly by the processing circuit 150 in cooperation with each element of the medium conveying device based on a program previously stored in the storage device 140. The flow of the operation shown in Fig. 22 is executed in place of the flowchart shown in Fig. 14. Note that the processes of steps S301 to S303 and S308 to S310 are the same as the processes of steps S101 to S103 and S105 to S107 in Fig. 14, so their description will be omitted, and only the processes of steps S304 to S307 will be described below.

[0114] In step S304, the movement detection unit 153 acquires a movement detection signal from the movement sensor 423 (step S304).

[0115] Next, the movement detection unit 153 judges whether the second pressing member 422 has moved by a predetermined amount or more based on the acquired movement detection signal (step S305). When the signal value of the movement detection signal changes from a value indicating that the arm 422b does not exist to a value indicating that the arm 422b exists, the movement detection unit 153 judges that the second pressing member 422 has moved by a predetermined amount or more. In that case, the movement detection unit 153 judges that cardboard (or a card, a booklet, etc.) is being fed as the medium. In this way, the movement detection unit 153 detects the movement of the second pressing member 422 due to the medium being fed. When the movement detection unit 153 does not judge that the second pressing member 422 has moved by the predetermined amount or more, the control unit 151 shifts the process to step S307 without executing any particular process.

[0116] On the other hand, when the movement detection unit 153 determines that the second pressing member 422 has moved by a predetermined amount or more, the control unit 151 controls the motor 131 to change the rotation speed of each roller (step S306). When the second pressing member 422 has moved by a predetermined amount or more, that is, when thick paper is being fed, the control unit 151 changes the rotation speed of each roller so as to reduce the medium feeding speed and / or conveying speed compared to when general paper such as PPC paper is being fed. That is, the control unit 151 reduces the rotation speed of the feed roller 112, the separation roller 113, the first conveying roller 114, the second conveying roller 115, the first discharge roller 117, and / or the second discharge roller 118.

[0117] In this way, the control unit 151 changes the rotation speeds of the feed roller 112, separation roller 113, first conveyor roller 114, second conveyor roller 115, first discharge roller 117 and / or second discharge roller 118 based on the detection result by the movement detection unit 153. When a DC motor is used as the motor 131, the motor 131 needs to ensure sufficient torque to feed and transport the thick paper smoothly. When the thick paper is being fed, the control unit 151 reduces the rotation speed of each roller to ensure sufficient torque, thereby allowing the thick paper to be fed and transported smoothly.

[0118] Next, the control unit 151 determines whether or not the entire medium has been imaged in the same manner as in step S104 (step S307). If the entire medium has not yet been imaged, the control unit 151 returns the process to step S304 and repeats the processes of steps S304 to S307. On the other hand, if the entire medium has been imaged, the control unit 151 proceeds to step S308.

[0119] In the medium conveying device according to this embodiment, the movement sensor 423 may be omitted, and the medium conveying device may execute the medium reading process shown in FIG.

[0120] As described above in detail, the medium conveying device is able to prevent the occurrence of medium jams even when the second pressing member 422 is provided to be movable.

[0121] FIG. 23 is a schematic diagram for explaining a second pressing member 522 in a medium conveying device according to yet another embodiment.

[0122] The second pressing member 522 shown in FIG. 23 is used in place of the second pressing member 122 of the medium conveying device 100. The second pressing member 522 has a similar configuration to the second pressing member 522. However, the second pressing members 522 are arranged at intervals in the width direction A2 perpendicular to the medium conveying direction, and each second pressing member 522 is arranged outside the multiple feed rollers 112 (side wall side of the conveying path) in the width direction A2. In this case, too, the medium conveying device can equalize the force applied to both sides of the fed medium in the width direction A2, thereby suppressing the occurrence of skew of the medium. Note that the first pressing members 121 are also arranged at intervals in the width direction A2, and each first pressing member 121 may be arranged outside the multiple feed rollers 112 in the width direction A2 (side wall side of the conveying path).

[0123] As described above in detail, the medium conveying device is able to prevent the occurrence of medium jams even when a plurality of second pressing members 522 are arranged.

[0124] FIG. 24 is a schematic diagram for explaining a first pressing member 621 and a second pressing member 622 in a medium conveying device according to yet another embodiment.

[0125] 24 are used in place of the first pressing member 121 and the second pressing member 422 of the medium conveying device. The first pressing member 621 and the second pressing member 622 have the same configuration as the first pressing member 121 and the second pressing member 422. However, the first pressing member 621 is disposed in the lower housing 101, and the second pressing member 622 is disposed in the upper housing 102.

[0126] The first pressing member 621 is disposed so as to intersect with the first nip portion N1 as viewed from the width direction A2, and presses the medium fed in the height direction A3 upward. The upward direction in the height direction A3 is an example of a first direction. The first pressing member 621 is provided so as to be movable downward in the height direction A3 by the medium fed. The downward direction in the height direction A3 is an example of a second direction. On the other hand, the second pressing member 622 is disposed so as to intersect with the first virtual straight line L1 as viewed from the width direction A2, and presses the medium fed in the height direction A3 downward. The second pressing member 622 is provided so as to be movable to a position not intersecting with the second virtual straight line L2 as viewed from the width direction A2.

[0127] By the second pressing member 622 pressing the medium being fed downward, the leading edge of the medium pressed upward by the first pressing member 621 is prevented from floating up and being prevented from being guided between the first conveying roller 114 and the second conveying roller 115, which causes the medium to jam.

[0128] In this way, the first pressing member is disposed in one of the lower housing 101 and the upper housing 102, and the second pressing member is disposed in the other of the lower housing 101 and the upper housing 102. This enables the medium transport device to stiffen the medium along the width direction A2 by the first pressing member and the second pressing member, thereby improving the rigidity of the medium.

[0129] As described above in detail, the medium conveying device is able to prevent medium jams from occurring even when the first pressing member 621 is arranged in the lower housing 101 and the second pressing member 622 is arranged in the upper housing 102.

[0130] 25 is a diagram showing a schematic configuration of a processing circuit 750 in a medium conveying device according to yet another embodiment. The processing circuit 750 is used in place of the processing circuit 150 of the medium conveying device 100, and executes medium reading processing and the like in place of the processing circuit 150. The processing circuit 750 has a control circuit 751, an abnormality detection circuit 752, a movement detection circuit 753, and the like. Each of these components may be formed of an independent integrated circuit, microprocessor, firmware, and the like.

[0131] The control circuit 751 is an example of a control unit, and has the same functions as the control unit 151. The control circuit 751 receives an operation signal from the operation device 105 or the interface device 132, a medium signal from the medium sensor 111, a detection result of a medium feeding abnormality from the abnormality detection circuit 752, and a detection result of the movement of the second pressing member from the movement detection circuit 753. The control circuit 751 controls the motor 131 based on each piece of received information, and also obtains an input image from the imaging device 116 and outputs it to the interface device 132.

[0132] The abnormality detection circuit 752 is an example of an abnormality detection unit, and has the same function as the abnormality detection unit 152. The abnormality detection circuit 752 receives a movement speed signal from the encoder 323, detects a medium feeding abnormality based on the received movement speed signal, and outputs the detection result to the control circuit 751.

[0133] The movement detection circuit 753 is an example of a movement detection unit, and has the same function as the movement detection unit 153. The movement detection circuit 753 receives a movement detection signal from the movement sensor 423, detects the movement of the second pressing member 422 based on the received movement detection signal, and outputs the detection result to the control circuit 751.

[0134] As described above in detail, the medium conveying device can prevent the occurrence of medium jams even when the processing circuit 750 is used. [Explanation of symbols]

[0135] 100 medium conveying device, 101 lower housing, 102 upper housing, 112 feeding roller, 113 separation roller, 114 first conveying roller, 115 second conveying roller, 121, 621 first pressing member, 122, 222, 322, 422, 522, 622 second pressing member, 151 control unit, 152 abnormality detection unit, 153 movement detection unit, 323 encoder

Claims

1. a feed roller for feeding the medium; a separation roller disposed opposite the feed roller; a first conveying roller disposed downstream of the feed roller in a medium conveying direction; a second conveying roller disposed opposite the first conveying roller; a first pressing portion that is disposed so as to intersect with a first nip portion between the feeding roller and the separation roller when viewed from a direction perpendicular to the medium transport direction, and that presses the medium, which is fed in a direction perpendicular to the medium transport path, in a first direction; a second pressing portion that is disposed downstream of the first nip portion in the medium transport direction so as to intersect with a first virtual line extending from the first nip portion to the downstream side in the medium transport direction when viewed from a direction perpendicular to the medium transport direction, and that presses the medium fed in the direction perpendicular to the medium transport path in a second direction opposite to the first direction, the first pressing portion is provided so as to be movable in the second direction by a medium being fed, the second pressing portion is provided so as not to intersect with a second virtual line connecting a center position of the second nip portion between the first conveying roller and the second conveying roller and a center position of the first nip portion when viewed from a direction perpendicular to the medium conveying direction, or is movable to a position so as not to intersect with the second virtual line due to the medium being fed. A medium transport device comprising:

2. the first pressing portion is disposed on the upper side in a direction perpendicular to the medium transport path, and presses the medium being fed downward; The medium transport device according to claim 1 , wherein the second pressing portion is disposed on a lower side in a direction perpendicular to the medium transport path, and presses the medium being fed upward.

3. an encoder disposed at a tip of the second pressing portion and rotatably provided in accordance with the medium being fed; The medium transport device according to claim 1 , further comprising an abnormality detection unit that detects a medium feeding abnormality based on the rotation of the encoder.

4. a movement detection unit that detects the movement of the second pressing unit due to the medium being fed; 4. The medium transport device according to claim 1, further comprising: a control unit that changes a rotation speed of the feed roller based on a detection result by the movement detection unit.

5. As the feeding roller, a plurality of feeding rollers are arranged at intervals in a direction perpendicular to a medium conveying direction, 5. The medium transport device according to claim 1, wherein the first pressing portion and the second pressing portion are disposed between the plurality of feed rollers in a direction perpendicular to a medium transport direction.

6. A first housing; A second housing provided so as to be openable and closable relative to the first housing, the first pressing portion is disposed in one of the first housing and the second housing, The medium transport device according to claim 1 , wherein the second pressing portion is disposed on the other of the first housing and the second housing.

Images