Media transport device

Abstract

To provide a medium conveying apparatus in which a backing is provided in a unit movably located to face an imaging sensor, configured to further reduce the apparatus size.SOLUTION: A medium conveying apparatus includes: a conveying section to convey a medium, a first unit, a second unit located to face the first unit, an imaging section provided in the first unit to image the medium conveyed by the conveying section; a backing including a facing surface, and provided in the second unit in such a way that the facing surface is rotatable between a facing position at which the facing surface faces the imaging section, and a non-facing position at which the facing surface deviates from the facing position; a guide portion to slidably guide the second unit in a direction perpendicular to a medium conveying surface so that the second unit moves in the direction perpendicular to the medium conveying surface; and a support portion to rotatably support the backing. The support portion is located inside the guide portion.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to a medium conveyance device, and more particularly to a medium conveyance device that conveys and images a medium.

Background Art

[0002] In a medium conveyance device such as a scanner device that images a medium while conveying it, it is required to image media of various thicknesses well. For this purpose, a medium conveyance device has been developed in which a unit arranged opposite to an imaging unit that images a medium is arranged to be movable according to the thickness of the medium. Generally, in such a medium conveyance device, a backing is provided on a unit arranged opposite to the imaging unit, and the medium conveyance device has a function of changing the background color of the medium to white or black by switching the position of the backing.

[0003] An image reading device having an imaging unit that images a document and a backing having a facing surface with white is disclosed (see Patent Document 1). This image reading device switches the backing between a facing position where the facing surface faces the imaging unit and the imaging unit can acquire a white reference image, and a non-facing position where the facing surface is removed from the facing position and the imaging unit can acquire a black reference image.

[0004] An image reading device is disclosed that is provided movably in the conveyance direction of a document within a sensor case attached along a conveyance path, and has a reading sensor that reads one side of the document, and a background member provided opposite to the reading sensor across the conveyance path (see Patent Document 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a medium transport device in which a backing is provided on a unit that is movably arranged to face an imaging unit, it is desired to make the device size smaller.

[0007] An object of the present invention is to enable the device size to be made smaller in a medium transport device in which a backing is provided on a unit that is movably arranged to face an imaging unit.

Means for Solving the Problem

[0008] A medium transport device according to one aspect of the present invention includes a transport unit that transports a medium, a first unit, a second unit arranged to face the first unit, an imaging unit provided in the first unit and imaging the medium transported by the transport unit, a backing provided in the second unit and rotatable between an opposing position where the opposing surface faces the imaging unit and a non-opposing position where the opposing surface is out of the opposing position, a guide unit that slidably guides the second unit in a direction orthogonal to the medium transport surface so that the second unit moves in a direction orthogonal to the medium transport surface, and a support unit that rotatably supports the backing, and the support unit is arranged within the guide unit.

Advantages of the Invention

[0009] According to the present invention, in a medium transport device in which a backing is provided on a unit that is movably arranged to face an imaging unit, it is possible to make the device size smaller.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] Hereinafter, a media conveyance device according to an aspect of the present invention will be described with reference to the drawings. However, note that the technical scope of the present invention is not limited to those embodiments, and extends to the invention described in the claims and its equivalents.

[0012] FIG. 1 is a perspective view showing a media conveyance device 100 configured as an image scanner. The media conveyance device 100 conveys and images a media that is a document. The media is paper, cardboard, plastic card, passport, booklet, or the like. The media conveyance device 100 may also be a facsimile machine, a copying machine, a printer multifunction peripheral (MFP), or the like.

[0013] The media conveyance device 100 includes a lower housing 101, an upper housing 102, a placement table 103, a discharge table 104, an operation device 105, a display device 106, and the like. In FIG. 1, arrow A1 indicates the media conveyance direction, arrow A2 indicates the width direction orthogonal to the media conveyance direction A1, and arrow A3 indicates the height direction orthogonal to the media conveyance surface. Hereinafter, upstream refers to the upstream in the media conveyance direction A1, and downstream refers to the downstream in the media conveyance direction A1.

[0014] The upper housing 102 is disposed at a position covering the upper surface of the media conveyance device 100 and is engaged with the lower housing 101. The placement table 103 is engaged with the lower housing 101 so as to be able to place the conveyed media. The discharge table 104 is engaged with the lower housing 101 so as to be able to hold the discharged media. Note that the discharge table 104 may be engaged with the upper housing 102.

[0015] The operation device 105 has an input device such as a button and an interface circuit that acquires signals from the input device, accepts an input operation by a user, and outputs an operation signal corresponding to the user's input operation. The display device 106 has a display including a liquid crystal, an organic EL (Electro-Luminescence), etc., and an interface circuit that outputs image data to the display, and displays the image data on the display.

[0016] FIG. 2 is a diagram for explaining the conveyance path inside the medium conveyance device 100.

[0017] The conveyance path inside the medium conveyance device 100 has a medium sensor 111, a feed roller 112, a separation roller 113, a first conveyance roller 114, a second conveyance roller 115, an imaging unit 116, a first discharge roller 117, a second discharge roller 118, etc. The feed roller 112, the separation roller 113, the first conveyance roller 114, the second conveyance roller 115, the first discharge roller 117, or the second discharge roller 118 is an example of a conveyance unit that conveys the medium. Note that the number of each roller is not limited to one, and the number of each roller may be plural.

[0018] The upper surface of the lower housing 101 forms a lower guide 101a of the medium conveyance path, and the lower surface of the upper housing 102 forms an upper guide 102a of the medium conveyance path. The lower guide 101a or the upper guide 102a forms a medium conveyance surface that conveys the medium.

[0019] The medium sensor 111 is disposed upstream of the feed roller 112 and the separation roller 113. The medium sensor 111 has a contact detection sensor and detects whether a medium is placed on the placement table 103. The medium sensor 111 generates and outputs a medium signal whose signal value changes between a state where a medium is placed on the placement table 103 and a state where no medium is placed. Note that the medium sensor 111 is not limited to a contact detection sensor, and as the medium sensor 111, any other sensor capable of detecting the presence or absence of a medium, such as an optical detection sensor, may be used.

[0020] The feed roller 112 is provided on the lower housing 101 and sequentially separates and feeds the medium placed on the mounting table 103 from below. The separation roller 113 is a so-called brake roller or retard roller, which is provided on the upper housing 102, is arranged opposite to the feed roller 112, and rotates in the direction opposite to the medium feed direction.

[0021] The first transport roller 114 and the second transport roller 115 are provided downstream of the feed roller 112 and the separation roller 113 and upstream of the imaging unit 116. The first transport roller 114 and the second transport roller 115 are respectively provided on the upper housing 102 and the lower housing 101 so as to face each other, and transport the medium fed by the feed roller 112 and the separation roller 113 to the imaging unit 116.

[0022] The imaging unit 116 is arranged downstream of the first transport roller 114 and the second transport roller 115 and upstream of the first discharge roller 117 and the second discharge roller 118. The imaging unit 116 includes a first imaging unit 116a, a second imaging unit 116b, and an imaging unit guide 116c that are arranged opposite to each other across the medium transport path.

[0023] The first imaging unit 116a is an example of the first unit and is provided on the lower housing 101. The second imaging unit 116b is an example of the second unit and is arranged on the upper housing 102 opposite to the first imaging unit 116a. The imaging unit guide 116c is provided outside the upstream side of the second imaging unit 116b. The imaging unit guide 116c guides the leading end of the medium transported by the first transport roller 114 and the second transport roller 115 between the first imaging unit 116a and the second imaging unit 116b.

[0024] The first discharge roller 117 and the second discharge roller 118 are provided downstream of the imaging unit 116. The first discharge roller 117 and the second discharge roller 118 are provided facing each other on the upper housing 102 and the lower housing 101 respectively, and discharge the medium conveyed by the first conveyance roller 114 and the second conveyance roller 115 and imaged by the imaging unit 116 onto the discharge table 104.

[0025] The medium placed on the placement table 103 is conveyed in the medium conveyance direction A1 between the lower guide 101a and the upper guide 102a by the rotation of the feed roller 112 in the direction of arrow A4 in FIG. 2. The separation roller 113 rotates in the direction of arrow A5, that is, in the direction opposite to the medium feed direction, when feeding the medium. By the action of the feed roller 112 and the separation roller 113, when a plurality of media are placed on the placement table 103, only the medium in contact with the feed roller 112 among the media placed on the placement table 103 is separated. Thereby, the conveyance of the media other than the separated media is restricted (prevention of double feeding).

[0026] The medium is fed between the first conveyance roller 114 and the second conveyance roller 115 while being guided by the lower guide 101a and the upper guide 102a. The medium is fed between the first imaging unit 116a and the second imaging unit 116b by the rotation of the first conveyance roller 114 and the second conveyance roller 115 in the directions of arrow A6 and arrow A7 respectively. The medium read by the first imaging unit 116a and the second imaging unit 116b is discharged onto the discharge table 104 by the rotation of the first discharge roller 117 and the second discharge roller 118 in the directions of arrow A8 and arrow A9 respectively.

[0027] FIG. 3 and FIG. 4 are schematic diagrams for explaining the imaging unit 116.

[0028] As shown in FIGS. 3 and 4, the first imaging unit 116a is provided with a first light transmissive member 121a, a first light source 122a, a first imaging sensor 123a, a first backing member 124a, a first wall member 125a, and the like. The second imaging unit 116b is provided with a second light transmissive member 121b, a second light source 122b, a second imaging sensor 123b, a second backing member 124b, a second wall member 125b, and the like.

[0029] The first light transmissive member 121a and the second light transmissive member 121b are formed of transparent glass. Note that the first light transmissive member 121a and the second light transmissive member 121b may be formed of transparent plastic or the like. The first light transmissive member 121a and the second light transmissive member 121b form a medium conveyance surface.

[0030] The first light source 122a is provided on the opposite side of the second backing member 124b with the first light transmissive member 121a and the second light transmissive member 121b interposed therebetween. The first light source 122a has an LED (Light Emitting Diode). The first light source 122a irradiates light toward the surface of the medium conveyed to the position of the imaging unit 116 (when the medium is not being conveyed, the second backing member 124b or the second wall member 125b of the opposing second imaging unit 116b).

[0031] Similarly, the second light source 122b is provided on the opposite side of the first backing member 124a with the second light transmissive member 121b and the first light transmissive member 121a interposed therebetween. The second light source 122b has an LED. The second light source 122b irradiates light toward the back surface of the medium conveyed to the position of the imaging unit 116 (when the medium is not being conveyed, the first backing member 124a or the first wall member 125a of the opposing first imaging unit 116a).

[0032] The first imaging sensor 123a is an example of an imaging unit, and is provided on the opposite side of the second backing member 124b with the first light transmissive member 121a and the second light transmissive member 121b interposed therebetween. The first imaging sensor 123a has a line sensor by a CIS (Contact Image Sensor) of an equi-magnification optical system type having an imaging element by CMOS (Complementary Metal Oxide Semiconductor) linearly arranged in the main scanning direction. Further, the first imaging sensor 123a has a lens that forms an image on the imaging element, and an A / D converter that amplifies an electrical signal output from the imaging element and performs analog / digital (A / D) conversion. The first imaging sensor 123a generates and outputs an input image obtained by imaging the surface and the periphery of the medium conveyed by the conveying unit at the imaging position L1. Further, when the medium is not being conveyed, the first imaging sensor 123a generates and outputs a reference image obtained by imaging the second backing member 124b.

[0033] Similarly, the second imaging sensor 123b is provided on the opposite side of the first backing member 124a with the first light transmissive member 121a and the second light transmissive member 121b interposed therebetween. The second imaging sensor 123b has a line sensor by a CIS of an equi-magnification optical system type having an imaging element by CMOS linearly arranged in the main scanning direction. Further, the second imaging sensor 123b has a lens that forms an image on the imaging element, and an A / D converter that amplifies an electrical signal output from the imaging element and performs analog / digital conversion. The second imaging sensor 123b generates and outputs an input image obtained by imaging the back surface and the periphery of the medium conveyed by the conveying unit at the imaging position L2. Further, when the medium is not being conveyed, the second imaging sensor 123b generates and outputs a reference image obtained by imaging the first backing member 124a.

[0034] Instead of the line sensor using a CIS of an equal magnification optical system type equipped with an imaging device using CMOS, a line sensor using a CIS of an equal magnification optical system type equipped with an imaging device using a CCD (Charge Coupled Device) may be used. Further, a line sensor of a reduced magnification optical system type equipped with an imaging device using CMOS or CCD may be used. Further, the set of the second light source 122b, the second imaging sensor 123b, the first backing member 124a, and the first wall member 125a may be omitted.

[0035] The first backing member 124a is provided below the first light transmissive member 121a and at a position facing the second light source 122b and the second imaging sensor 123b. The first backing member 124a has a first facing surface 126a facing the second imaging sensor 123b. The first facing surface 126a has, for example, a white color and functions as a white reference member for performing image correction such as shading based on the image signal obtained by imaging the first facing surface 126a. Note that the first facing surface 126a only needs to have a color other than black and may have a color other than white. The first backing member 124a is rotatably supported about the first rotation axis 127a and rotates by the driving force from a first motor described later. The first backing member 124a is rotatably provided between a facing position where the first facing surface 126a faces the second imaging sensor 123b (the position shown in FIG. 3) and a non-facing position where the first facing surface 126a is out of the facing position (the position shown in FIG. 4).

[0036] The second backing member 124b is an example of a backing, and is provided above the second light transmissive member 121b and at a position facing the first light source 122a and the first imaging sensor 123a. The second backing member 124b has a second facing surface 126b facing the first imaging sensor 123a. The second facing surface 126b is an example of a facing surface, has, for example, a white color, and functions as a white reference member for correcting an image such as shading based on an image signal obtained by imaging the second facing surface 126b. Note that the second facing surface 126b may have a color other than black, and may have a color other than white. The second backing member 124b is rotatably supported about a second rotation axis 127b, and rotates by a driving force from a first motor. The second backing member 124b is rotatably provided between a facing position where the second facing surface 126b faces the first imaging sensor 123a (the position shown in FIG. 3) and a non-facing position where the second facing surface 126b is out of the facing position (the position shown in FIG. 4).

[0037] The first wall member 125a is provided at a position facing the second imaging sensor 123b when the first backing member 124a is disposed at the non-facing position. The surface of the first wall member 125a facing the second imaging sensor 123b has a color different from that of the first facing surface 126a such as black.

[0038] Similarly, the second wall member 125b is provided at a position facing the first imaging sensor 123a when the second backing member 124b is disposed at the non-facing position. The surface of the second wall member 125b facing the first imaging sensor 123a has a color different from that of the second facing surface 126b such as black.

[0039] Hereinafter, the first light transmissive member 121a and the second light transmissive member 121b may be collectively referred to as the light transmissive member 121. Also, the first light source 122a and the second light source 122b may be collectively referred to as the light source 122. The first imaging sensor 123a and the second imaging sensor 123b may be collectively referred to as the imaging sensor 123. Also, the first backing member 124a and the second backing member 124b may be collectively referred to as the backing member 124. Also, the first wall member 125a and the second wall member 125b may be collectively referred to as the wall member 125. Also, the first opposing surface 126a and the second opposing surface 126b may be collectively referred to as the opposing surface 126.

[0040] As shown in FIG. 3, when the backing member 124 is disposed at the opposing position, the light emitted from the light source 122 is reflected by the opposing surface 126 of the backing member 124 in the region where no medium exists and forms an image on the imaging sensor 123. In the image based on the image signal generated at this time, the pixels corresponding to the region where no medium exists have white. On the other hand, as shown in FIG. 4, when the backing member 124 is disposed at the non-opposing position, the light emitted from the light source 122 is reflected by the wall member 125 and forms an image on the imaging sensor 123. In the image based on the image signal generated at this time, the pixels corresponding to the region where no medium exists have black.

[0041] FIGS. 5(A) and (B) are schematic views for explaining the second backing member 124b. FIG. 5(A) is a perspective view of the second backing member 124b, and FIG. 5(B) is an exploded view of the second backing member 124b.

[0042] As shown in FIGS. 5(A) and (B), the second backing member 124b includes a plate member 131, a sheet member 132, a second support member 133, a second cam member 134, a spring member 135, a third support member 136, and the like.

[0043] The plate member 131 is a plate-shaped member having a concave cross-section when viewed from the width direction A2 and provided so as to extend along the width direction A2.

[0044] The sheet member 132 is a seal having one surface with the second opposing surface 126b and the other surface with an adhesive surface, and is provided so as to extend along the width direction A2. By attaching the adhesive surface of the sheet member 132 to the bottom surface of the plate member 131, the second opposing surface 126b is provided on the bottom surface of the plate member 131.

[0045] The second support member 133 is attached to one end of the plate member 131 in the width direction A2 and rotatably supports the plate member 131. Thereby, the second support member 133 rotatably supports the second backrest member 124b.

[0046] The second cam member 134 is provided so as to rotate by a driving force from a first motor described later. The second cam member 134 is attached to the second support member 133 so that the second support member 133 rotates as the second cam member 134 rotates. The second support member 133 and the second cam member 134 are an example of a support portion.

[0047] The spring member 135 is a screw recoiling spring or the like. One end of the spring member 135 is attached to the upper housing 102 and the other end is attached to the second cam member 134, and a force that rotates in a direction opposite to the direction of rotation by the driving force from the first motor is applied to the second cam member 134.

[0048] The third support member 136 is an example of the second support portion. The third support member 136 is attached to the end of the plate member 131 on the side opposite to the second support member 133 in the width direction A2 and supports the plate member 131.

[0049] FIG. 6 is a schematic diagram for explaining the plate member 131 and the second support member 133. FIG. 6 is a perspective view of the plate member 131 and the second support member 133 as viewed from the side of the second support member 133.

[0050] As shown in FIG. 6, the plate member 131 has a first concave portion 131a and a first hole portion 131b. On the other hand, the second support member 133 has a first protrusion portion 133a, a first claw portion 133b, and a first shaft portion 133c. When the first protrusion portion 133a is fitted into the first concave portion 131a, the second support member 133 is positioned with respect to the plate member 131. When the first claw portion 133b is engaged with the first hole portion 131b, the second support member 133 is attached to the plate member 131. A shaft portion of a second cam member 134 described later is fitted into the first shaft portion 133c.

[0051] FIG. 7 is a schematic diagram for explaining the plate member 131 and the third support member 136. FIG. 7 is a perspective view of the plate member 131 and the third support member 136 as viewed from the side of the third support member 136.

[0052] As shown in FIG. 7, the plate member 131 further has a second concave portion 131c and a second hole portion 131d. On the other hand, the third support member 136 has a second protrusion portion 136a, a second claw portion 136b, and a second shaft portion 136c. When the second protrusion portion 136a is fitted into the second concave portion 131c, the third support member 136 is positioned with respect to the plate member 131. When the second claw portion 136b is engaged with the second hole portion 131d, the third support member 136 is attached to the plate member 131. The second shaft portion 136c is provided coaxially with the first shaft portion 133c of the second support member 133 and is engaged with a hole portion formed at an end portion on the side of the third support member 136 in the width direction A2 of the second imaging unit 116b.

[0053] FIGS. 8 and 9 are schematic diagrams for explaining the second imaging unit 116b and the second cam member 134. FIG. 8 is a perspective view of the second imaging unit 116b and the second cam member 134 as viewed from the side of the second support member 133, and FIG. 9 is an exploded view of the second imaging unit 116b and the second cam member 134.

[0054] As shown in FIGS. 8 and 9, the second imaging unit 116b has a protrusion portion 116d, a first engagement member 116e, and the like.

[0055] The protruding portion 116d is provided at one end in the width direction A2 of the second imaging unit 116b (the end on the side of the second support member 133). Inside the protruding portion 116d, a through hole is formed that penetrates the wall portion of the second imaging unit 116b in the width direction A2. The second support member 133 is arranged such that the first shaft portion 133c faces the through hole of the protruding portion 116d.

[0056] The first engaging member 116e is an example of the first engaging portion and the engaging portion, and is formed of a member with high slidability such as a plastic member. It is engaged with the outer peripheral surface of the protruding portion 116d so as to cover the protruding portion 116d. The first engaging member 116e is provided so as to slide with respect to a first guiding member described later. Since the first engaging member 116e is formed as a member separate from the second imaging unit 116b, even if the first engaging member 116e is damaged by friction with the first guiding member, the medium conveying device 100 can be inexpensively restored by replacing parts. Note that the first engaging member 116e may be formed as a member integral with the second imaging unit 116b.

[0057] The second cam member 134 has a rotating portion 134a, a third shaft portion 134b, a fitting portion 134c, etc. The rotating portion 134a is attached to one end (the outer end) in the width direction A2 of the third shaft portion 134b and is provided so as to be rotatable about the third shaft portion 134b. The fitting portion 134c is formed at the other end (the inner end) in the width direction A2 of the third shaft portion 134b and has a shape that fits with the first shaft portion 133c of the second support member 133. The fitting portion 134c is fitted with the first shaft portion 133c of the second support member 133 through the inside of the first engaging member 116e and the protruding portion 116d. Thereby, the third shaft portion 134b of the second cam member 134 is disposed inside the first engaging member 116e, and the second backing member 124b is provided so as to rotate as the second cam member 134 rotates.

[0058] FIG. 10 is a schematic diagram for explaining the second imaging unit 116b and the third support member 136. FIG. 10 is a perspective view of the second imaging unit 116b as viewed from the side of the third support member 136.

[0059] As shown in FIG. 10, the second imaging unit 116b further includes a third hole portion 116f, a second engaging member 116g, and the like.

[0060] The third hole portion 116f is provided at an end portion on the side opposite to the end portion on the second support member 133 side (the end portion on the third support member 136 side) in the width direction A2 of the second imaging unit 116b. By engaging the second shaft portion 136c of the third support member 136 with the third hole portion 116f, the second imaging unit 116b rotatably supports the third support member 136.

[0061] The second engaging member 116g is an example of the second engaging portion and is a boss having a rectangular shape with rounded corners. Since the second engaging member 116g has a rectangular shape, it is possible to suppress the occurrence of breakage. Note that the second engaging member 116g may have a circular shape. The second engaging member 116g is formed of a member having high slidability, such as a plastic member. The second engaging member 116g is provided at an end portion on the side opposite to the end portion on the second support member 133 side (the end portion on the third support member 136 side) in the width direction A2 of the second imaging unit 116b. That is, the first engaging member 116e is provided at one end of the width direction A2 orthogonal to the medium conveyance direction of the second imaging unit 116b, and the second engaging member 116g is provided at the other end of the width direction A2 orthogonal to the medium conveyance direction of the second imaging unit 116b.

[0062] In the example shown in FIG. 10, two second engaging members 116g are arranged side by side at intervals in the height direction A3 perpendicular to the medium conveyance surface. The distance between the upper end of the second engaging member 116g arranged on the upper side and the lower end of the second engaging member 116g arranged on the lower side is set to be larger than the distance between the upper end and the lower end of the first engaging member 116e. Note that only one second engaging member may be arranged as the second engaging member. In that case, the distance between the upper end and the lower end of the one second engaging member is set to be larger than the distance between the upper end and the lower end of the first engaging member 116e. Further, three or more second engaging members may be arranged as the second engaging member. In that case, the distance between the upper end of the second engaging member arranged at the uppermost side and the lower end of the second engaging member arranged at the lowermost side is set to be larger than the distance between the upper end and the lower end of the first engaging member 116e.

[0063] The second engaging member 116g is provided so as to slide with respect to a second guiding member described later. Since the second engaging member 116g is formed as a member separate from the second imaging unit 116b, the medium conveyance device 100 can be inexpensively restored by replacing parts even when the second engaging member 116g is damaged due to friction with the second guiding member. Note that the second engaging member 116g may be formed as a member integral with the second imaging unit 116b.

[0064] FIG. 11 is a schematic diagram for explaining the second imaging unit 116b. FIG. 11 is a perspective view of the entire second imaging unit 116b.

[0065] As shown in FIG. 11, the second imaging unit 116b further includes an elastic member 116h. The elastic member 116h is a spring member such as a compression coil spring, and one end thereof is attached to the upper surface of the second imaging unit 116b, and the other end thereof is provided so as to be supported by the upper housing 102. The second imaging unit 116b is biased in the direction toward the first imaging unit 116a by the elastic member 116h. Note that the elastic member 116h may be another spring member such as a leaf spring or a rubber member.

[0066] The second imaging unit 116b has a so-called auto-gap mechanism that moves in the height direction A3 according to the thickness of the conveyed medium. The second imaging unit 116b is arranged by the elastic member 116h so that the distance between the second imaging unit 116b and the first imaging unit 116a becomes sufficiently small. Thereby, when a thin medium such as PPC paper or thin paper is conveyed, the distance from the medium to the imaging sensor 123 at the imaging position becomes constant. Therefore, even when a CIS of an equal magnification optical system type with a shallow depth of field is used, the occurrence of out-of-focus is suppressed, and the imaging sensor 123 can acquire a stable image. On the other hand, when a medium thicker than the distance between the second imaging unit 116b and the first imaging unit 116a, such as thick paper, a booklet, or a passport, is conveyed, the second imaging unit 116b is pushed up by the thickness of the medium. Therefore, the thick medium is well guided between the first imaging unit 116a and the second imaging unit 116b.

[0067] As shown in FIG. 11, the first engagement member 116e is arranged upstream of the center position P3 of the downstream end P1 and the upstream end P2 of the second imaging unit 116b in the medium conveyance direction A1. That is, the first engagement member 116e is arranged at a position closer to the upstream end P2 than the downstream end P1 of the second imaging unit 116b in the medium conveyance direction A1.

[0068] In the medium conveyance device 100, when a thick medium is conveyed at high speed, the medium vigorously collides with the imaging unit guide 116c and applies an impact force toward the downstream side in the medium conveyance direction A1 to the second imaging unit 116b. Due to the impact force from the medium, a rocking force is applied to the second imaging unit 116b so as to rock downstream and downward about the arrangement position of the first engagement member 116e supported by the upper housing 102. As described above, the second imaging unit 116b is pushed up by the thickness of the medium, but due to this rocking force, a so-called cocking force that rotates while rising is generated in the second imaging unit 116b. Due to this cocking force, the first engagement member 116e is caught by the first guide member, the smooth rising of the second imaging unit 116b is hindered, and the conveyance load of the medium increases.

[0069] In the media conveyance device 100, the first engagement member 116e is disposed on the upstream side. As a result, when an impact force is applied to the second imaging unit 116b by a thick medium conveyed at high speed, the rotational moment applied to the second imaging unit 116b decreases (the radius of swing of the second imaging unit 116b swinging decreases). Therefore, the swinging force applied to the second imaging unit 116b becomes smaller, and the cogging force with respect to the upward movement of the second imaging unit 116b becomes smaller. Therefore, the media conveyance device 100 can smoothly raise the first engagement member 116e along the first guide member and suppress an increase in the conveyance load of the media. Therefore, the media conveyance device 100 can convey a thick medium at high speed well. Further, the media conveyance device 100 can suppress the occurrence of media jams or elongation between media in the input image by suppressing an increase in the conveyance load of the media. Furthermore, the media conveyance device 100 can suppress an increase in conveyance torque and suppress an increase in power consumption by suppressing an increase in the conveyance load of the media.

[0070] Note that the first engagement member 116e may be disposed on the upstream side of the center-of-gravity position of the second imaging unit 116b in the media conveyance direction A1. Also in that case, the media conveyance device 100 can convey a thick medium at high speed well.

[0071] FIGS. 12 and 13 are schematic views for explaining the operation of the second cam member 134. FIGS. 12 and 13 are schematic views of the periphery of the imaging unit 116 as viewed from the side. FIG. 12 shows the imaging unit 116 with the backing member 124 disposed at the opposing position, and FIG. 13 shows the imaging unit 116 with the backing member 124 disposed at the non-opposing position.

[0072] As shown in FIGS. 12 and 13, the media conveyance device 100 further includes a first support member 141, a first cam member 142, a first motor 143, a gear 144, a third cam member 145, an arm member 146, and the like.

[0073] The first support member 141 is attached to one end of the first backing member 124a (the end on the side of the second support member 133) in the width direction A2, and rotatably supports the first backing member 124a.

[0074] The first cam member 142 is provided to rotate by the driving force from the first motor 143. The first cam member 142 is attached to the first support member 141 such that the first support member 141 rotates as the first cam member 142 rotates. The first cam member 142 has a protrusion 142a that engages with the arm member 146.

[0075] The first motor 143 rotates according to a control signal from a processing circuit described later, and generates a driving force for rotating the first backing member 124a and the second backing member 124b to arrange them at non - opposing positions.

[0076] The gear 144 has a first gear portion 144a that meshes with a gear portion 143a provided on the rotation shaft of the first motor 143, and a second gear portion 144b that meshes with the third cam member 145, and rotates according to the driving force from the first motor 143.

[0077] The third cam member 145 has a gear portion 145a that meshes with the second gear portion 144b of the gear 144, and rotates as the gear 144 rotates. Further, the third cam member 145 has a protrusion 145b that engages with the arm member 146, and by rotating as the gear 144 rotates, slides the arm member 146 in the height direction A3.

[0078] The arm member 146 has a rail portion 146a that extends along the medium conveyance direction A1 and engages with the protrusion 145b of the third cam member 145, and slides in the height direction A3 as the third cam member 145 rotates. Further, the arm member 146 has an upper surface portion 146b and a bottom surface portion 146d provided in a recess 146c that extends along the height direction A3. The upper surface portion 146b rises as the arm member 146 rises, abuts against the rotating portion 134a of the second cam member 134, and rotates the second cam member 134. The bottom surface portion 146d rises as the arm member 146 rises, abuts against the protrusion 142a of the first cam member 142, and rotates the first cam member 142.

[0079] In the state shown in FIG. 12, the rotating portion 134a of the second cam member 134 is not in contact with the arm member 146 and is biased in the direction of arrow A11 by the spring member 135. Further, the protrusion 142a of the first cam member 142 is not in contact with the bottom surface portion 146d of the arm member 146 and is biased in the direction of arrow A12 by a spring member similar to the spring member 135. In this state, the first backing member 124a and the second backing member 124b are arranged at the opposing positions shown in FIG. 3.

[0080] On the other hand, as shown in FIG. 13, when the first motor 143 generates a driving force and the rotating shaft of the first motor 143 rotates in the direction of arrow A13, the gear 144 rotates in the direction of arrow A14, and the third cam member 145 rotates in the direction of arrow A15. As a result, the protrusion 145b of the third cam member 145 moves upward to the left, and the arm member 146 moves in the direction of arrow A16 (upward) so that the protrusion 145b can move leftward along the rail portion 146a. The upper surface portion 146b of the arm member 146 abuts against the rotating portion 134a of the second cam member 134, and rotates the second cam member 134 in the direction opposite to the direction of arrow A11 against the biasing force of the spring member 135. Further, the bottom surface portion 146d of the arm member 146 abuts against the protrusion 142a of the first cam member 142, and rotates the first cam member 142 in the direction opposite to the direction of arrow A12 against the biasing force of the spring member. As a result, the first backing member 124a and the second backing member 124b are arranged at the non-opposing positions shown in FIG. 4.

[0081] FIG. 14 is a schematic diagram for explaining the first guide member 102b. FIG. 14 is a perspective view showing the periphery of the end portion on the side of the first engaging member 116e of the second imaging unit 116b.

[0082] As shown in FIG. 14, the upper housing 102 has a first guide member 102b. The first guide member 102b is an example of a guide portion, and is a rail formed so as to extend in the height direction A3 orthogonal to the medium conveyance surface at the end portion on the side of the first engaging member 116e in the width direction A2 of the medium conveyance path. The first engaging member 116e is engaged with the first guide member 102b so as to be slidable along the first guide member 102b. Thereby, the first engaging member 116e is guided by the first guide member 102b along the height direction A3 orthogonal to the medium conveyance surface. The first guide member 102b guides the second imaging unit 116b so as to be slidable in the height direction A3 orthogonal to the medium conveyance surface so that the second imaging unit 116b moves in the height direction A3 orthogonal to the medium conveyance surface. Further, the second cam member 134 disposed inside the first engaging member 116e is disposed inside the first guide member 102b.

[0083] FIG. 15 is a schematic diagram for explaining the second guide member 102c. FIG. 15 is a perspective view showing the periphery of the end portion on the side of the second engaging member 116g of the second imaging unit 116b.

[0084] As shown in FIG. 15, the upper housing 102 further includes a second guiding member 102c. The second guiding member 102c is an example of a second guiding portion, and is a rail formed to extend in the height direction A3 orthogonal to the medium conveyance surface at the end on the second engaging member 116g side in the width direction A2 of the medium conveyance path. The second engaging member 116g is engaged with the second guiding member 102c so as to be slidable along the second guiding member 102c. Thereby, the second guiding member 102c supports the second engaging member 116g so as to be slidable in the height direction A3 orthogonal to the medium conveyance surface. The second guiding member 102c guides the second imaging unit 116b so as to be slidable in the height direction A3 orthogonal to the medium conveyance surface so that the second imaging unit 116b moves in the height direction A3 orthogonal to the medium conveyance surface. Further, the third support member 136, which is the rotation axis of the second backing member 124b, is not disposed within the second engaging member 116g and the second guiding member 102c. Note that the third support member 136 may be provided so as to be disposed within the second engaging member 116g and the second guiding member 102c.

[0085] As described above, when a thick medium is conveyed, the second imaging unit 116b is pushed up by the thickness of the medium. Along with this, the first engaging member 116e disposed inside the second cam member 134 slides upward along the first guiding member 102b. That is, the rotation fulcrum of the second backing member 124b is disposed within the rail for the sliding movement of the second imaging unit 116b.

[0086] If the rotation fulcrum of the backing member is disposed outside the rail for the sliding movement of the imaging unit, it is necessary to separate the rotation fulcrum and the rail so that they do not interfere with each other. In order to slide the imaging unit smoothly, the rail is preferably disposed near the central position of the imaging unit in the medium conveyance direction. In order to rotate the backing member smoothly, the support member and the cam member for rotating the backing member need to have a certain size. Therefore, the rotation fulcrum needs to be disposed at a position sufficiently away from the central position of the imaging unit so that the support member, the cam member, and the rail do not contact each other, and the imaging unit needs to have a certain size. However, if the imaging unit is enlarged, the size of the apparatus becomes larger and the force required to push up the imaging unit becomes larger, so that the conveyance load associated with the conveyance of the medium increases.

[0087] In the medium conveyance apparatus 100, since the rotation fulcrum of the second backing member 124b is disposed within the rail for the sliding movement of the second imaging unit 116b, it is possible to reduce the size of the second imaging unit 116b. As a result, the medium conveyance apparatus 100 can be made smaller in size, suppress an increase in the conveyance load associated with the conveyance of the medium, and convey the medium smoothly.

[0088] Note that, in order to stably slide the second imaging unit 116b, it is necessary to increase the size of the first engagement member 116e in the height direction A3 that abuts against and is guided by the first guide member 102b. However, the third shaft portion 134b of the second cam member 134 that rotatably supports the second backing member 124b has a cylindrical shape, and the first engagement member 116e that covers the third shaft portion 134b has a cylindrical shape.

[0089] As described above, in the medium transport device 100, the second engagement member 116g disposed on the opposite side of the first engagement member 116e in the second imaging unit 116b is provided so as to slide along the second guide member 102c. The distance between the upper end and the lower end of the second engagement member 116g is set to be larger than the distance between the upper end and the lower end of the first engagement member 116e. Thereby, the medium transport device 100 can stably slide the second imaging unit 116b by the second engagement member 116g provided on the opposite side of the first engagement member 116e in the width direction A2.

[0090] Further, in the medium transport device 100, among the two engagement members provided at both ends in the width direction A2 in the second imaging unit 116b, only the length in the height direction A3 of one second engagement member 116g is increased, and the length in the height direction A3 of the other first engagement member 116e is shortened. Thereby, the medium transport device 100 reduces the area of the region where the second imaging unit 116b abuts on each guide member at both ends in the width direction A2, and can reduce the sliding load between the second imaging unit 116b and each guide member. Therefore, even when release twisting or dimensional defects occur due to resin molding of the second imaging unit 116b, the medium transport device 100 can reduce the sliding load between the second imaging unit 116b and each guide member. Therefore, the medium transport device 100 can slide the second imaging unit 116b satisfactorily.

[0091] FIG. 16 is a block diagram showing a schematic configuration of the medium transport device 100.

[0092] In addition to the above-described configuration, the medium transport device 100 further includes a second motor 151, an interface device 152, a storage device 160, a processing circuit 170, and the like.

[0093] The second motor 151 has one or a plurality of motors, and rotates the feed roller 112, the separation roller 113, the first conveyance roller 114, the second conveyance roller 115, the first discharge roller 117, and the second discharge roller 118 according to a control signal from the processing circuit 170 to convey the medium. Note that one of the first conveyance roller 114 and the second conveyance roller 115 may be a driven roller that rotates in a driven manner with respect to the other roller. Also, one of the first discharge roller 117 and the second discharge roller 118 may be a driven roller that rotates in a driven manner with respect to the other roller.

[0094] The interface device 152 has an interface circuit conforming to a serial bus such as USB, for example, and is electrically connected to an information processing device (for example, a personal computer, a portable information terminal, etc.) not shown in the figure to transmit and receive an input image and various types of information. Further, instead of the interface device 152, a communication unit having an antenna that transmits and receives wireless signals and a wireless communication interface device for transmitting and receiving signals through a wireless communication line according to 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 according to a communication protocol such as a wired LAN.

[0095] The storage device 160 has a memory device such as a RAM (Random Access Memory) and a ROM (Read Only Memory), a fixed disk device such as a hard disk, or a portable storage device such as a flexible disk and an optical disk. Further, the storage device 160 stores computer programs, databases, tables, etc. used for various processes of the medium conveyance device 100. The computer program may be installed in the storage device 160 from a computer-readable portable recording medium using a known setup program or the like. The portable recording medium is, for example, a CD-ROM (compact disc read only memory), a DVD-ROM (digital versatile disc read only memory), etc.

[0096] The processing circuit 170 operates based on a program pre-stored in the storage device 160. The processing circuit is, for example, a CPU (Central Processing Unit). As the processing circuit 170, a DSP (digital signal processor), LSI (large scale integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), etc. may be used.

[0097] The processing circuit 170 is connected to an operation device 105, a display device 106, a media sensor 111, an imaging sensor 123, a first motor 143, a second motor 151, an interface device 152, a storage device 160, etc., and controls these respective parts. The processing circuit 170 performs drive control of the first motor 143 and the second motor 151, imaging control of the imaging sensor 123, etc. based on the media signal received from the media sensor 111, acquires an input image from the imaging sensor 123, and transmits it to an information processing device via the interface device 152.

[0098] FIG. 17 is a diagram showing a schematic configuration of the storage device 160 and the processing circuit 170.

[0099] As shown in FIG. 17, a control program 161, an image acquisition program 162, etc. are stored in the storage device 160. These respective programs are functional modules implemented by software operating on a processor. The processing circuit 170 reads each program stored in the storage device 160 and operates according to each read program. Thereby, the processing circuit 170 functions as a control unit 171 and an image acquisition unit 172.

[0100] FIG. 18 is a flowchart showing an example of the operation of the media reading process of the media conveyance device 100.

[0101] Hereinafter, an example of the operation of the medium reading process of the medium conveyance device 100 will be described with reference to the flowchart shown in FIG. 18. The flowchart of the operation described below is mainly executed by the processing circuit 170 in cooperation with each element of the medium conveyance device 100 based on a program stored in the storage device 160 in advance.

[0102] First, the control unit 171 waits until an instruction to read a medium is input by the user using the operation device 105 or the information processing device, and a control signal instructing the reading of the medium is received from the operation device 105 or the interface device 152 (step S101).

[0103] Next, the control unit 171 acquires a medium signal from the medium sensor 111, and determines whether a medium is placed on the mounting table 103 based on the acquired medium signal (step S102). If no medium is placed on the mounting table 103, the control unit 171 ends the series of steps.

[0104] On the other hand, if a medium is placed on the mounting table 103, the control unit 171 controls the first motor 143 to place the backrest member 124 in the opposing position (step S103).

[0105] Next, the image acquisition unit 172 causes the imaging sensor 123 to image the backrest member 124, and acquires a reference image from the imaging sensor 123 (step S104).

[0106] Next, the control unit 171 controls the first motor 143 to place the backing member 124 at a designated position specified by the user among the opposing position or the non-opposing position (step S105). The designated position is specified by the user using the operation device 105 or the information processing device before the medium reading process is executed and is preset in the storage device 160. By placing the backing member 124 at the opposing position, the medium conveyance device 100 can make the background in the input image white and can acquire an image in which the background is not prominent. On the other hand, by placing the backing member 124 at the non-opposing position, the medium conveyance device 100 can make the background in the input image black and can more accurately crop a medium having white from the input image.

[0107] Next, the control unit 171 rotates the feed roller 112, the separation roller 113, the first conveyance roller 114, the second conveyance roller 115, the first discharge roller 117, and / or the second discharge roller 118 (step S106). The control unit 171 drives the second motor 151 to rotate each roller and convey the medium.

[0108] Next, the image acquisition unit 172 causes the imaging sensor 123 to image the medium and acquires an input image from the imaging sensor 123 (step S107).

[0109] Next, the image acquisition unit 172 corrects the acquired input image using the reference image acquired in step S104 (step S108). The image acquisition unit 172 performs shading correction on the input image using the reference image by utilizing known image processing techniques.

[0110] Next, the image acquisition unit 172 outputs the corrected input image by transmitting it to the information processing device via the interface device 152 (step S109).

[0111] Next, the control unit 171 determines whether there is any medium remaining on the mounting table 103 based on the medium signal received from the medium sensor 111 (step S110). If there is any medium remaining on the mounting table 103, the control unit 171 returns the process to step S107 and repeats the processes of steps S107 to S110.

[0112] On the other hand, if there is no medium remaining on the mounting table 103, the control unit 171 stops the feed roller 112, the separation roller 113, the first conveyance roller 114, the second conveyance roller 115, the first discharge roller 117, and / or the second discharge roller 118 (step S111). The control unit 171 controls the second motor 151 to stop each roller and ends a series of steps.

[0113] As described in detail above, in the medium conveyance device 100, the rotation axis of the second backing member 124b is disposed within the first engagement member 116e for vertically sliding the second imaging unit 116b. Thereby, the medium conveyance device 100 can share the auto-gap mechanism of the second imaging unit 116b and the rotation mechanism of the second backing member 124b. Therefore, in the medium conveyance device 100 in which the second backing member 124b is provided in the second imaging unit 116b movably opposed to the first imaging sensor 123a, it has become possible to make the device size smaller.

[0114] FIG. 19 is a schematic diagram for explaining a second imaging unit 216b in a medium conveyance device according to another embodiment.

[0115] As shown in FIG. 19, the medium conveyance device according to the present embodiment has a second imaging unit 216b instead of the second imaging unit 116b.

[0116] The second imaging unit 216b has the same configuration as the second imaging unit 116b. However, the second imaging unit 216b has a first engaging member 216e instead of the first engaging member 116e. The first engaging member 216e is an example of an engaging portion. Similar to the first engaging member 116e, it is provided at one end in the width direction A2 of the second imaging unit 216b, with a second cam member 134 disposed inside and guided by the first guiding member 102b. However, the first engaging member 216e is provided such that the length in the height direction A3 orthogonal to the medium conveyance surface is longer than the length in the medium conveyance direction A1. Thereby, the medium conveyance device can stably slide the second imaging unit 216b by the first engaging member 216e.

[0117] In this case, the second engaging member provided on the side opposite to the first engaging member 216e in the second imaging unit 216b may be provided in a cylindrical shape, that is, such that the length in the height direction A3 is substantially the same as the length in the medium conveyance direction A1. That is, the distance between the upper end and the lower end of the second engaging member may be set to be shorter than the distance between the upper end and the lower end of the first engaging member 216e. Thereby, the medium conveyance device can reduce the area of the region where the second imaging unit 216b contacts the respective guiding members at both ends in the width direction A2, and reduce the sliding load between the second imaging unit 216b and the respective guiding members. Therefore, the medium conveyance device can slide the second imaging unit 216b satisfactorily.

[0118] As described in detail above, even when the medium conveyance device is provided such that the length in the height direction A3 of the first engaging member 216e is longer than the length in the medium conveyance direction A1, the device size can be made smaller.

[0119] FIG. 20 is a schematic diagram for explaining a second imaging unit 316b in a medium conveyance device according to still another embodiment.

[0120] As shown in FIG. 20, the medium conveyance device according to this embodiment has a second imaging unit 316b instead of the second imaging unit 116b.

[0121] The second imaging unit 316b has the same configuration as the second imaging unit 116b. However, the second imaging unit 316b has a third engaging member 316e and a fourth engaging member 316i instead of the first engaging member 116e. The third engaging member 316e is an example of a third engaging portion, and like the first engaging member 116e, it is provided at one end in the width direction A2 of the second imaging unit 316b, with a second cam member 134 disposed inside, and is guided by the first guide member 102b. On the other hand, the fourth engaging member 316i is an example of a fourth engaging portion, and is provided at one end in the width direction A2 of the second imaging unit 316b and above the third engaging member 316e, and is guided by the first guide member 102b. The second cam member 134 is not disposed inside the fourth engaging member 316i. Thereby, the medium conveyance device can stably slide the second imaging unit 316b by the third engaging member 316e and the fourth engaging member 316i.

[0122] In this case, the second engaging member provided on the opposite side of the third engaging member 316e and the fourth engaging member 316i in the second imaging unit 316b may be provided in a cylindrical shape, that is, the length in the height direction A3 is substantially the same as the length in the medium conveyance direction A1. That is, the distance between the upper end and the lower end of the second engaging member may be set to be shorter than the distance between the lower end of the third engaging member 316e and the upper end of the fourth engaging member 316i. Thereby, the medium conveyance device can reduce the area of the region where the second imaging unit 316b contacts each guide member at both ends in the width direction A2, and can reduce the sliding load between the second imaging unit 316b and each guide member. Therefore, the medium conveyance device can slide the second imaging unit 316b satisfactorily.

[0123] As described in detail above, when the fourth engaging member 316i is provided above the third engaging member 316e, the medium conveyance device can also make the device size smaller.

[0124] FIG. 21 is a schematic diagram for explaining a second imaging unit 416b in a media transport device according to still another embodiment.

[0125] As shown in FIG. 21, the media transport device according to the present embodiment has a second imaging unit 416b instead of the second imaging unit 116b.

[0126] The second imaging unit 416b has the same configuration as the second imaging unit 116b. However, the second imaging unit 416b has a third engagement member 416e and a fourth engagement member 416i instead of the first engagement member 116e. The third engagement member 416e and the fourth engagement member 416i each have the same configuration as the third engagement member 316e and the fourth engagement member 316i, respectively. However, the fourth engagement member 416i is provided below the third engagement member 416e.

[0127] In this case as well, the second engagement member provided on the opposite side of the third engagement member 416e and the fourth engagement member 416i in the second imaging unit 416b may be provided such that the length in the height direction A3 is substantially the same as the length in the media transport direction A1. That is, the distance between the upper end and the lower end of the second engagement member may be set to be shorter than the distance between the upper end of the third engagement member 416e and the lower end of the fourth engagement member 416i.

[0128] As described in detail above, even when the fourth engagement member 416i is provided below the third engagement member 416e in the media transport device, the device size can be made smaller.

[0129] FIG. 22 is a diagram showing a schematic configuration of a processing circuit 570 in a media transport device according to still another embodiment. The processing circuit 570 is used instead of the processing circuit 170 of the media transport device 100 and executes media reading processing and the like instead of the processing circuit 170. The processing circuit 570 includes a control circuit 571, an image acquisition circuit 572, and the like. Note that each of these units may be configured by an independent integrated circuit, microprocessor, firmware, or the like.

[0130] The control circuit 571 is an example of a control unit and has the same functions as the control unit 171. The control circuit 571 receives an operation signal from the operation device 105 or the interface device 152 and a medium signal from the medium sensor 111, and controls the first motor 143 and the second motor 151 based on each received piece of information.

[0131] The image acquisition circuit 572 is an example of an image acquisition unit and has the same functions as the image acquisition unit 172. The image acquisition circuit 572 acquires an input image from the imaging sensor 123, corrects the acquired input image, and outputs it to the interface device 152.

[0132] As described in detail above, even when the processing circuit 570 is used, the size of the medium conveyance device can be made smaller.

[0133] Although the preferred embodiments have been described above, the embodiments are not limited thereto. For example, the first imaging unit may be provided in the upper housing 102, and the second imaging unit may be provided in the lower housing 101 so as to be movable according to the thickness of the medium to be conveyed.

Description of Reference Numerals

[0134] 100 Medium conveyance device, 102b First guide member, 102c Second guide member, 116a First imaging unit, 116b Second imaging unit, 116e First engagement member, 116g Second engagement member, 123a First imaging sensor, 124b Second backrest member, 126b Second opposing surface, 133 Second support member, 136 Third support member, 216e First engagement member, 316e Third engagement member, 316i Fourth engagement member

Claims

1. A conveying unit for conveying a medium, a first unit, a second unit disposed opposite to the first unit, an imaging unit provided in the first unit and configured to image the medium conveyed by the conveying unit, a backing provided in the second unit, having an opposing surface, and being rotatable between an opposing position where the opposing surface faces the imaging unit and a non-opposing position where the opposing surface is out of the opposing position, a guiding portion for guiding the second unit to be slidably movable in a direction orthogonal to the medium conveying surface so that the second unit moves in a direction orthogonal to the medium conveying surface, and a supporting portion for rotatably supporting the backing, wherein the supporting portion is disposed within the guiding portion, A medium conveying device characterized by the above.

2. A first engaging portion provided at one end of the second unit in a direction orthogonal to the medium conveying direction of the second unit, having the supporting portion disposed therein, and being guided by the guiding portion, a second engaging portion provided at the other end of the second unit in a direction orthogonal to the medium conveying direction of the second unit, and a second guiding portion for slidably supporting the second engaging portion in a direction orthogonal to the medium conveying surface, wherein the distance between the upper end and the lower end of the second engaging portion is set to be larger than the distance between the upper end and the lower end of the first engaging portion. The medium conveying device according to Claim 1.

3. A third engaging portion provided in the second unit, having the supporting portion disposed therein, and being guided by the guiding portion, and a fourth engaging portion provided in the second unit and above or below the third engaging portion and being guided by the guiding portion. The medium conveying device according to Claim 1.

4. The second unit further includes an engaging portion provided in the second unit, having the supporting portion disposed therein, and being guided by the guiding portion, wherein the engaging portion is provided such that the length in the direction orthogonal to the medium conveying surface is longer than the length in the medium conveying direction. The medium conveying device according to Claim 1.

5. The second unit further includes an engaging portion provided in the second unit, having the supporting portion disposed therein, and being guided by the guiding portion, wherein the engaging portion is disposed at a position closer to the upstream end than the downstream end of the second unit in the medium conveying direction. The medium conveying device according to Claim 1.

Images