JP7626875B2 - Media transport device - Google Patents

Description

The present disclosure relates to a media conveying device.

Generally, in media transport devices such as scanners that capture images of media while transporting them, paper dust or dirt adhering to the media may come into contact with rollers or guides used to transport the media, fall off the media, and accumulate inside the device. Such media transport devices capture images of the media using a light source and an optical element that receives light emitted from the light source and reflected by the media being transported. In the media transport device, if paper dust or dirt enters the path of the light received by the optical element, noise may occur in the image captured of the media.

A document reading device that transports a document and reads the document at a predetermined position on a contact glass has been disclosed (see Patent Document 1). In this document reading device, a guide member provided at the entrance to the contact glass has multiple holes, and a dust suction member is arranged behind the position of the guide member where the holes are arranged.

A paper dust removal device is disclosed that has a paper dust collection case with an opening facing the surface of the registration roller, and a cleaning blade whose tip abuts against the surface of the registration roller to scrape off the paper dust (see Patent Document 2).

An image reading device is disclosed that has a dustproof member that holds foreign objects that fall through the gap between the transport guide and the transport roller in the hole where the transport roller is provided (see Patent Document 3). In this image reading device, the dustproof member separates the space between the transport guide and the scanner unit that reads the image of the document.

Patent No. 3829055 Patent No. 4115876 JP 2020-21979 A

In media transport devices, it is necessary to prevent paper dust or dirt from entering the path of the light received by the optical element.

The media conveying device of the embodiment aims to prevent paper dust or debris from entering the path of light received by the optical element.

A medium transport device according to one aspect of an embodiment includes a housing frame having a medium guide surface in which a recess having a first opening is formed, a light source frame arranged in the recess and having a second opening and a light source, an optical element that receives reflected light emitted from the light source and reflected by the medium transported along the medium guide surface and passing through the first opening and the second opening, a first gap formed between the housing frame and the light source frame, a second gap formed between the first opening and the second opening, a first path from the first gap to the second gap, a shielding member arranged on the first path, and a storage section for storing paper powder or debris shielded by the shielding member , the storage section being provided outside the first path .

According to this embodiment, the media conveying device is able to prevent paper dust or debris from entering the path of the light received by the optical element.

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 only and are not restrictive of the invention as claimed.

1 is a perspective view showing a medium conveying device 100 according to an embodiment. 2 is a diagram for explaining a transport path inside the medium transport device 100. FIG. 5 is a schematic diagram for explaining a first lighting device 116a etc. 4 is a schematic diagram for explaining a cover 101b. FIG. 2 is a schematic diagram for explaining a housing frame 107 and the like. FIG. 11 is a schematic diagram for explaining a first storage portion 107c. FIG. 2 is a schematic diagram for explaining a light source frame 108 and the like. FIG. 11 is a schematic diagram for explaining a shielding member 135 and the like. FIG. 11 is a schematic diagram for explaining a shielding member 135 and the like. FIG. 11 is a schematic diagram for explaining a shielding member 135 and the like. FIG. 13A, 13B, and 13C are schematic diagrams for explaining the inclination. 11 is a schematic diagram for explaining second storage portions 136a and 136b. FIG. 5 is a schematic diagram for explaining a path of movement of paper dust or dirt. FIG. 4 is a schematic diagram for explaining a cover 101b. FIG. 1 is a block diagram showing a schematic configuration of a medium conveying device 100. FIG. FIG. 2 is a diagram showing a schematic configuration of a storage device 150 and a processing circuit 160. 10 is a flowchart illustrating an example of the operation of a medium reading process. 13 is a schematic diagram for explaining another first storage portion 207c. FIG. 13 is a schematic diagram for explaining other housing frames 307 etc. 13 is a schematic diagram for explaining other housing frames 407 etc. 5A to 5C are schematic diagrams for explaining other housing frames 507 and the like. FIG. 13 is a diagram showing a schematic configuration of another processing circuit 660.

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, please note that the technical scope of the present invention is not limited to these embodiments, but extends to the inventions described in the claims and their equivalents.

Figure 1 is a perspective view showing a medium transport device 100 configured as an image scanner. The medium transport device 100 transports a medium, which is an original document, and captures an image. The medium is paper, thin paper, thick paper, a card, a booklet, an envelope, etc. The medium transport device 100 may be a facsimile, a copier, a multifunction printer (MFP, Multifunction Peripheral), etc.

The media transport device 100 comprises a lower housing 101, an upper housing 102, a loading platform 103, an ejection platform 104, an operation device 105, and a display device 106. In Fig. 1, arrow A1 indicates the media transport direction, arrow A2 indicates the width direction perpendicular to the media transport direction, and arrow A3 indicates the height direction perpendicular to the media guide surface. In the following, upstream refers to the upstream side of the media transport direction A1, and downstream refers to the downstream side of the media transport direction A1.

The upper housing 102 is positioned to cover the top surface of the media transport device 100, and is rotatably engaged with the lower housing 101 by a hinge so that it can be opened and closed when media becomes jammed, when cleaning the inside of the media transport device 100, etc.

The loading platform 103 engages with the lower housing 101 and places the media to be fed and transported on it. The ejection platform 104 engages with the upper housing 102 and places the ejected media on it. The ejection platform 104 may also engage with the lower housing 101.

The operation device 105 has an input device such as a button and an interface circuit that acquires signals from the input device, accepts input operations 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.

Figure 2 is a diagram illustrating the transport path inside the media transport device 100.

The transport path inside the media transport device 100 includes a media sensor 111, a feed roller 112, a separation roller 113, a first transport roller 114, a second transport roller 115, a lighting device 116, an imaging device 117, a first discharge roller 118 and a second discharge roller 119, etc.

The number of each of the feed roller 112, separation roller 113, first conveying roller 114, second conveying roller 115, first discharge roller 118 and/or second discharge roller 119 is not limited to one, and may be multiple. In this case, the multiple feed rollers 112, separation roller 113, first conveying roller 114, second conveying roller 115, first discharge roller 118 and/or second discharge roller 119 are arranged at intervals in the width direction A2 perpendicular to the medium conveying direction.

The lower housing 101 includes a housing frame 107 and a light source frame 108. 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. The lower guide 101a and the upper guide 102a function as media guide surfaces. That is, the housing frame 107 and the light source frame 108 have media guide surfaces.

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 an optical detection sensor, may be used as the media sensor 111.

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 arranged opposite the feed roller 112. The separation roller 113 is arranged so that it can rotate or stop in the opposite direction to the medium feeding direction. It is preferable that the rotation axis of the separation roller 113 is arranged downstream of the rotation axis of the feed roller 112. As a result, the leading edge of the medium fed by the feed roller 112 and the separation roller 113 passes through the nip portion between the feed roller 112 and the separation roller 113, then heads downward and comes into contact with the lower guide 101a. Therefore, paper dust or dirt present on the lower guide 101a is carried downstream by the leading edge of the fed medium. Alternatively, the feed roller 112 may be provided in the upper housing 102 and the separation roller 113 may be provided in the lower housing 101, and the feed roller 112 may feed the media placed on the placement table 103 in order from the top.

The first conveying roller 114 and the second conveying roller 115 are arranged downstream of the feed roller 112 and the separation roller 113 in the media conveying direction A1, and convey the medium fed by the feed roller 112 and the separation roller 113 to the imaging device 117. The first conveying roller 114 is provided in the upper housing 102, and the second conveying roller 115 is provided in the lower housing 101 opposite the first conveying roller 114. The second conveying roller 115 is an example of a conveying roller. It is preferable that the rotation axis of the first conveying roller 114 is arranged downstream of the rotation axis of the second conveying roller 115. As a result, the leading edge of the medium conveyed by the first conveying roller 114 and the second conveying roller 115 passes through the nip portion between the first conveying roller 114 and the second conveying roller 115, then heads downward and comes into contact with the lower guide 101a (the upper surface of the light source frame 108). Therefore, paper dust or dirt present on the lower guide 101a (the upper surface of the light source frame 108) is carried downstream by the leading edge of the transported medium.

The lighting device 116 is disposed downstream of the first transport roller 114 and the second transport roller 115 in the medium transport direction A1, and illuminates the medium transported by the first transport roller 114 and the second transport roller 115. The lighting device 116 includes a first lighting device 116a and a second lighting device 116b disposed opposite each other across the medium transport path.

The imaging device 117 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 117 includes a first imaging device 117a and a second imaging device 117b disposed opposite each other across the medium transport path. The first imaging device 117a and the second imaging device 117b are disposed opposite the first lighting device 116a and the second lighting device 116b, respectively, on the opposite side of the medium transport path across the first lighting device 116a and the second lighting device 116b.

The first discharge roller 118 and the second discharge roller 119 are arranged downstream of the imaging device 117 in the media transport direction A1, i.e., downstream of the first transport roller 114 and the second transport roller 115. The first discharge roller 118 and the second discharge roller 119 transport the medium transported by the first transport roller 114 and the second transport roller 115 further downstream and discharge the medium onto the discharge tray 104. The first discharge roller 118 is provided in the upper housing 102, and the second discharge roller 119 is provided in the lower housing 101 opposite the first discharge roller 118. The second discharge roller 119 is an example of a transport roller.

The media placed on the mounting table 103 is transported between the lower guide 101a and the upper guide 102a in the media transport direction A1 by the rotation of the feed roller 112 in the direction of the arrow A4, i.e., the media feed direction. The separation roller 113 rotates or stops in the direction of the arrow A5, i.e., the opposite direction to the media feed direction. When multiple media are placed on the mounting table 103, the feed roller 112 and the separation roller 113 act to separate only those media placed on the mounting table 103 that are in contact with the feed roller 112. This limits the transport of media other than the separated media (preventing double feeding).

The medium is guided by the lower guide 101a and the upper guide 102a and sent between the first transport roller 114 and the second transport roller 115. The medium is sent between the first imaging device 117a and the second imaging device 117b as the first transport roller 114 and the second transport roller 115 rotate in the directions of the arrows A6 and A7, respectively. The medium read by the imaging device 117 is discharged onto the discharge tray 104 as the first discharge roller 118 and the second discharge roller 119 rotate in the directions of the arrows A8 and A9, respectively.

Figure 3 is a schematic diagram for explaining the first lighting device 116a and the first imaging device 117a.

3, a recess 107a is formed in the medium guide surface (lower guide 101a) of the housing frame 107, and the recess 107a has a first opening 107b. Meanwhile, the light source frame 108 has a second opening 108a on its lower surface, and is disposed in the recess 107a of the housing frame 107 so that the second opening 108a faces the first opening 107b.

The first lighting device 116a is provided in the light source frame 108. The first lighting device 116a has a light source group 121 and a transparent member 122. The light source group 121 is an example of a light source and includes LEDs (Light Emitting Diodes) and the like. The light source group 121 emits light toward the medium transport path, i.e., toward the medium M being transported. The transparent member 122 is formed of glass, plastic, or the like, and transmits the light irradiated from the light source group 121 to the medium transport path. The upper surface of the transparent member 122 forms a medium guide surface.

The first imaging device 117a is provided on the housing frame 107. The first imaging device 117a has a reflecting member group 123, a lens group 124, an imaging sensor 125, etc. The reflecting member group 123 is a mirror or the like, and reflects light emitted from the light source group 121 and reflected by the transported medium M toward the lens group 124. The lens group 124 collects the reflected light reflected by the reflecting member group 123 and forms an image on the imaging sensor 125. The imaging sensor 125 is a reduced optical system type imaging sensor equipped with imaging elements using CCDs (Charge Coupled Devices) linearly arranged in the main scanning direction. The first imaging device 117a further has an A/D converter that amplifies the electrical signal output from the imaging sensor 125 and performs analog/digital (A/D) conversion. The first imaging device 117a generates and outputs an input image of the transported medium according to control from a processing circuit described later.

The light emitted from the light source group 121 passes through the transparent member 122, is reflected by the medium M transported along the medium guide surface (the upper surface of the transparent member 122), and passes through the transparent member 122 again. The light that passes through the transparent member 122 again passes through the second opening 108a and the first opening 107b, is reflected by the reflecting member group 123, is collected by the lens group 124, and is imaged by the image sensor 125. By forming the second opening 108a and the first opening 107b in the light source frame 108 and the housing frame 107, respectively, the light emitted from the light source group 121 and reflected by the medium reaches the reflecting member group 123, the lens group 124, and the image sensor 125 well.

The group of reflective members 123, the group of lenses 124 and the image sensor 125 are examples of optical elements, and receive the reflected light that is emitted from the group of light sources 121, reflected by the medium transported along the medium guide surface, and passes through the first opening 107b and the second opening 108a.

The second illumination device 116b has a light source group and a transparent member having the same configuration as the light source group 121 and the transparent member 122. The second imaging device 117b has a reflecting member group, a lens group, and an imaging sensor having the same configuration as the reflecting member group 123, the lens group 124, and the imaging sensor 125. The second imaging device 117b further has an A/D converter that amplifies the electrical signal output from the imaging sensor and performs analog/digital (A/D) conversion. The second imaging device 117b generates and outputs an input image of the transported medium according to control from a processing circuit described later. Note that the second illumination device 116b and the second imaging device 117b may be omitted.

Figure 4 is a schematic diagram for explaining the cover 101b. Figure 4 is a schematic diagram of the lower housing 101 viewed from above with the upper housing 102 and the mounting base 103 removed.

As shown in FIG. 4, the housing frame 107 has a cover 101b for covering the feed roller 112 and the second transport roller 115. The cover 101b forms the lower guide 101a, i.e., the media guide surface.

Figure 5 is a schematic diagram for explaining the positional relationship between the housing frame 107 and the light source frame 108. Figure 5 is a cross-sectional view of line A-A' in Figure 4.

5, at the upstream end of the light source frame 108, a first gap 131a is formed between the housing frame 107 and the light source frame 108. Also, at the downstream end of the light source frame 108, a first gap 131b is formed between the housing frame 107 and the light source frame 108. When paper dust or dirt attached to the medium comes into contact with each roller or each guide and falls from the medium into the medium transport path, the paper dust or dirt that has fallen into the medium transport path is pushed by the tip of the medium being transported and enters the lower housing 101 through the first gaps 131a and 131b. Therefore, it is possible to prevent the paper dust or dirt from accumulating around each roller, causing each roller to not rotate properly, and preventing the medium from being transported properly. Also, it is possible to prevent the paper dust or dirt from adhering to the transparent member 122 and causing noise in the input image generated by the imaging device 117.

In addition, a second gap 132 is formed between the first opening 107b formed on the upper surface of the housing frame 107 and the second opening 108a formed on the lower surface of the light source frame 108. That is, a first path 133a from the first gap 131a to the second gap 132 and a first path 133b from the first gap 131b to the second gap 132 are formed between the housing frame 107 and the light source frame 108. A dustproof shielding member 135 is arranged on the first path 133a and the first path 133b. The shielding member 135 is formed of a contracting member such as sponge (foam member) or rubber, and prevents paper dust or dirt that has entered the first path 133a from the first gap 131a and the paper dust or dirt that has entered the first path 133b from the first gap 131b from entering the second gap 132.

The housing frame 107 is provided with a first storage section 107c. The first storage section 107c is an example of a storage section, and stores paper dust or dirt shielded by the shielding member 135. The medium guide surface (lower guide 101a) of the housing frame 107 has a fourth opening 107d for arranging the second conveying roller 115. The first storage section 107c is arranged below the second conveying roller 115 so as to face the fourth opening 107d. The first storage section 107c stores paper dust or dirt that has entered the first path 133a from the first gap section 131a, as well as paper dust or dirt that has entered from the fourth opening 107d, so that the medium conveying device 100 can efficiently collect paper dust or dirt.

Between the shielding member 135 and the first gap 131a, a third opening 134 is formed that opens from the first path 133a toward the first storage section 107c. That is, the housing frame 107 is formed with a second path 133c for guiding the paper dust or dirt that enters from the first gap 131a and is shielded by the shielding member 135 from the third opening 134 to the first storage section 107c. By forming the second path 133c, the paper dust or dirt that enters the first path 133a from the first gap 131a is well contained in the first storage section 107c, and the accumulation of paper dust or dirt in the first path 133a is suppressed. Note that the third opening 134 may be omitted, and the medium conveying device 100 may not have the second path 133c.

In addition, the housing frame 107 has protrusions (ribs) protruding upward and recesses recessed downward, and the light source frame 108 has protrusions (ribs) protruding downward and recesses recessed upward. The housing frame 107 and the light source frame 108 are arranged so that the protrusions of the housing frame 107 are inserted into the recesses of the light source frame 108 and the protrusions of the light source frame 108 are inserted into the recesses of the housing frame 107. Due to the gap between the protrusions and recesses of the housing frame 107 and the protrusions and recesses of the light source frame 108, the first paths 133a, 133b are formed to have a labyrinth structure. This makes it difficult for paper dust or debris that has entered the first path 133a from the first gap 131a, and paper dust or debris that has entered the first path 133b from the first gap 131b, to reach the second gap 132, thereby preventing the paper dust or debris from entering the housing frame 107.

Figure 6 is a schematic diagram for explaining the first storage section 107c. Figure 6 is a schematic diagram of the periphery of the first storage section 107c viewed from the side.

As shown in Figure 6, the second transport roller 115 is positioned in the media transport direction A1 such that a gap L1 is provided between the upstream end E1 of the second transport roller 115 and the upstream wall W1 of the first storage section 107c. The second transport roller 115 is also positioned in the media transport direction A1 such that a gap L2 is provided between the downstream end E2 of the second transport roller 115 and the downstream wall W2 of the first storage section 107c. The second transport roller 115 is positioned in the media transport direction A1 such that the upstream gap L1 is smaller than the downstream gap L2.

The second conveying roller 115 rotates in the direction of the medium conveying direction A1 (arrow A6) on the medium guide surface. That is, the second conveying roller 115 rotates downward on the downstream side and rotates upward on the upstream side. Therefore, the paper dust or dirt that comes into contact with the second conveying roller 115 and peels off from the medium falls as the second conveying roller 115 rotates on the downstream side, while it tries to rise as the second conveying roller 115 rotates on the upstream side. In the medium conveying device 100, the second conveying roller 115 is arranged so that the gap L1 on the upstream side is smaller than the gap L2 on the downstream side, thereby preventing the paper dust or dirt contained in the first storage section 107c from returning to the medium conveying path as the second conveying roller 115 rotates. Therefore, the medium conveying device 100 can more efficiently store the paper dust or dirt in the first storage section 107c.

In addition, in the medium transport direction A1, the end E3 of the medium guide surface that forms the downstream end of the fourth opening 107d has an inclined surface that is positioned downward as it approaches the upstream side. This allows paper dust or dirt that comes into contact with the second transport roller 115 and is peeled off from the medium to fall along the end E3, allowing the medium transport device 100 to more efficiently store the paper dust or dirt in the first storage section 107c.

In addition, in the medium transport direction A1, the upper end E4 of the wall portion W1 on the upstream side of the first storage portion 107c, which forms the upstream end of the fourth opening 107d, has an inclined surface that is positioned downward as it approaches the upstream side. The upper end E4 of the wall portion W1 prevents the paper dust or debris contained in the first storage portion 107c from returning to the medium transport path as the second transport roller 115 rotates, so that the medium transport device 100 can more efficiently store the paper dust or debris in the first storage portion 107c.

In addition, convection caused by the rotation of the second conveyor roller 115 is unlikely to occur directly below the second conveyor roller 115. Therefore, by arranging the first storage section 107c directly below the second conveyor roller 115, the movement of the paper dust or garbage accumulated in the first storage section 107c is suppressed, and the first storage section 107c can efficiently accumulate the paper dust or garbage. In addition, the greater the distance between the lower surface of the second conveyor roller 115 and the bottom surface of the first storage section 107c, the more preferable it is so that the first storage section 107c can store a large amount of paper dust or garbage. In addition, since the paper dust or garbage only needs to enter the first storage section 107c from the gap between the fourth opening 107d and the second conveyor roller 115 in the medium conveying direction A1, there is no need to be a gap between the fourth opening 107d and the second conveyor roller 115 in the width direction A2. Therefore, the length of the fourth opening 107d in the width direction A2 is set to be substantially the same as the length of the second conveying roller 115 in the width direction A2.

Figure 7 is a schematic diagram for explaining the removal of the light source frame 108 and the shielding member 135. Figure 7 is a cross-sectional view of line A-A' in Figure 4 with the light source frame 108 and the shielding member 135 removed.

7, the light source frame 108 and the shielding member 135 are provided so as to be detachable from the lower housing 101, i.e., from the medium conveying device 100. This allows the user to remove the light source frame 108 and the shielding member 135 from the lower housing 101 to clean the medium conveying device 100, making it possible to easily remove paper dust or debris accumulated in the first paths 133a, 133b. Therefore, the medium conveying device 100 can improve the convenience for the user.

In addition, the housing frame 107 has a protrusion (rib) that protrudes upward at a position opposite the first opening 107b. This prevents the paper dust or dirt that has been blocked in the first path 133b by the shielding member 135 from falling from the first opening 107b when the light source frame 108 and the shielding member 135 are removed from the lower housing 101.

Figures 8, 9, and 10 are schematic diagrams for explaining the shielding member 135 and the housing frame 107. Figure 8 is a schematic diagram of the housing frame 107 with the light source frame 108 removed, viewed from above. Figure 9 is a cross-sectional view taken along line C-C' in Figure 8, showing the housing frame 107 with the shielding member 135 removed, viewed from diagonally above. Figure 10 is a cross-sectional view taken along line C-C' in Figure 8, showing the housing frame 107 with the shielding member 135 attached, viewed from the side.

8, the shielding member 135 has a square shape and is disposed so as to surround the first opening 107b and the second opening 108a facing the first opening 107b. The shielding member 135 is attached to the light source frame 108 so that no gap is generated between the shielding member 135 and the light source frame 108.

9, the housing frame 107 has a first rib 107e, a second rib 107f, and a third rib 107g that protrude upward, i.e., toward the light source frame 108 side. The first rib 107e, the second rib 107f, and the third rib 107g are arranged to surround the first opening 107b and the second opening 108a that faces the first opening 107b, and to face the shielding member 135. The first rib 107e is arranged upstream of the first opening 107b and the second opening 108a, and has a first plane 107h that is inclined so as to be positioned downward toward the upstream side. The second rib 107f is arranged downstream of the first opening 107b and the second opening 108a, and has a second plane 107i that is inclined so as to be positioned downward toward the upstream side. The third ribs 107g are disposed at both ends of the first opening 107b and the second opening 108a in the width direction A2, and have third planes 107j that are inclined so as to be positioned lower toward the outside.

10, the cross section of the shielding member 135 has a rectangular shape. One corner of the shielding member 135 is pressed against the first plane 107h. Similarly, one corner of the shielding member 135 is pressed against the second plane 107i and the third plane 107j. As a result, one corner of the shielding member 135 is crushed by the first plane 107h, the second plane 107i, and the third plane 107j, and no gap is generated between the shielding member 135 and the light source frame 108 and the housing frame 107. Therefore, the paper powder or dust that has entered the first path 133a from the first gap portion 131a and the paper powder or dust that has entered the first path 133b from the first gap portion 131b are more reliably prevented from entering the second gap portion 132.

Figures 11 (A), (B), and (C) are schematic diagrams for explaining the inclination of the first plane 107h, the second plane 107i, and the third plane 107j.

Figure 11 (A) is a graph showing the relationship between the amount of pushing in of the shielding member 135 (contraction member) and the repulsive force from the shielding member 135. The horizontal axis of Figure 11 (A) shows the amount of pushing in, and the vertical axis shows the repulsive force. Graph 1100 of Figure 11 (A) shows the repulsive force when the shielding member 135 is pushed in by abutting the flat surface of a specified rectangular member against the bottom surface (flat surface) of the shielding member 135. Graph 1101 shows the repulsive force when the shielding member 135 is pushed in by abutting the inclined first flat surface 107h against the corner of the shielding member 135.

In order to prevent the light source frame 108 from floating up due to the shielding member 135 (contraction member), the weight W of the light source frame 108 needs to be set to be greater than the repulsive force that the light source frame 108 receives from the shielding member 135. On the other hand, in order to reduce the weight of the medium conveying device 100, it is preferable that the weight W of the light source frame 108 is smaller (lighter). Therefore, it is preferable that the repulsive force from the shielding member 135 is smaller.

11(A), the repulsive force generated when the first plane 107h is brought into contact with the corner of the shielding member 135 and the shielding member 135 is pushed in is sufficiently smaller than the repulsive force generated when the shielding member 135 is brought into contact with a flat surface (flat surface) of the shielding member 135. By bringing the first plane 107h into contact with the corner of the shielding member 135, the medium conveying device 100 is able to sufficiently reduce the repulsive force from the shielding member 135, thereby reducing the weight of the light source frame 108 and enabling the weight of the medium conveying device 100 to be reduced.

It is preferable that the shielding member 135 is arranged so as to abut against the first plane 107h of the first rib 107e, but not abut against the peripheral region of the first plane 107h (the upper surface of the first rib 107e and the surface located at the bottom of the first rib 107e). Similarly, it is preferable that the shielding member 135 is arranged so as to abut against the second plane 107i of the second rib 107f, but not abut against the peripheral region of the second plane 107i (the upper surface of the second rib 107f and the surface located at the bottom of the second rib 107f). It is also preferable that the shielding member 135 is arranged so as to abut against the third plane 107j of the third rib 107g, but not abut against the peripheral region of the third plane 107j (the upper surface of the third rib 107g and the surface located at the bottom of the third rib 107g). As a result, the medium conveying device 100 is able to sufficiently reduce the repulsive force from the shielding member 135, thereby making it possible to reduce the weight of the light source frame 108 and the weight of the medium conveying device 100 itself.

11(B) is a schematic diagram of the periphery of the shielding member 135 as viewed from the side. Since the inclinations of the first plane 107h, the second plane 107i, and the third plane 107j are similar, the following description will be given of the first plane 107h as a representative.

As described above, in order to prevent the light source frame 108 from being lifted by the shielding member 135, the weight W of the light source frame 108 needs to be set to be greater than the repulsive force that the light source frame 108 receives from the shielding member 135. On the other hand, in order to reduce the weight of the medium conveying device 100, it is preferable that the weight W of the light source frame 108 is as small as possible.

In the example shown in Fig. 11B, the first plane 107h is inclined at an angle θ with respect to the height direction A3. A compressive force N is generated on the first plane 107h by the shielding member 135 along a direction perpendicular to the first plane 107h, and a frictional force μN is generated along the first plane 107h. μ is a friction coefficient having a value greater than 0 and less than 1. If the component of the compressive force N in the height direction A3 is P, the following formulas (1) and (2) are established, and from formulas (1) and (2), formula (3) is established for the ratio of the compressive force N to the weight W of the light source frame 108.
N=P/sinθ (1)
W=P+μNcosθ (2)
N/W=1/(sinθ+μcosθ) (3)

Figure 11 (C) is a graph showing the relationship between the ratio of the compressive force N by the shielding member 135 to the weight W of the light source frame 108 and the angle θ of the first plane 107h with respect to the height direction A3. The horizontal axis of Figure 11 (B) shows the angle θ of the first plane 107h with respect to the height direction A3, and the vertical axis shows the ratio of the compressive force N by the shielding member 135 to the weight W of the light source frame 108. As shown in Figure 11 (B), the smaller the angle θ, the larger the ratio of the compressive force N to the weight W, and the weight W can be made smaller with respect to the compressive force N. It is preferable that the angle θ is set in the range of, for example, 10° or more and 40° or less. As a result, the light source frame 108 is prevented from floating up without fixing the light source frame 108 with screws or the like, so that the medium conveying device 100 can reduce the parts cost.

In addition, it is preferable that the portion of the housing frame 107 that comes into contact with the shielding member 135 is mirror-polished or Teflon (registered trademark) coated. This enables the medium conveying device 100 to reduce the coefficient of friction between the housing frame 107 and the shielding member 135, and to increase the ratio of the compressive force N by the shielding member 135 to the weight W of the light source frame 108. Therefore, the medium conveying device 100 can generate a larger compressive force with a smaller pushing force, and can enhance the so-called wedge effect.

Figure 12 is a schematic diagram for explaining the second storage sections 136a, 136b. Figure 12 is a cross-sectional view along line B-B' in Figure 4.

As shown in FIG. 12, the second storage sections 136a and 136b are each disposed at the end of the first path 133a in the width direction A2 perpendicular to the media transport direction. The second storage sections 136a and 136b are an example of a storage section, and store paper dust or dirt that enters the first path 133a from the first gap 131a and is shielded by the shielding member 135. When air is blown onto the media transport path to remove (clean) the paper dust or dirt on the media transport path, the paper dust or dirt may enter the first path 133a from the first gap 131a. The paper dust or dirt that enters the first path 133a moves along the shielding member 135 to the end in the width direction A2 and is stored in the second storage sections 136a and 136b.

A user can collect the paper dust or debris contained in the second storage sections 136a, 136b by removing the light source frame 108 from the lower housing 101. This allows the medium conveying device 100 to prevent the paper dust or debris that has entered the first path 133a from accumulating in the first path 133a, making it possible to efficiently collect the paper dust or debris.

Figure 13 is a schematic diagram for explaining the path of movement of paper dust or dirt. Figure 13 is a cross-sectional view of the periphery of the light source frame 108 viewed from the side.

13, paper dust or dirt that enters the first path 133a from the first gap 131a enters the second path 133c from the third opening 134 and is stored in the first storage section 107c. Paper dust or dirt that does not enter the second path 133c enters along the first path 133a to the position of the shielding member 135. Paper dust or dirt that enters the position of the shielding member 135 moves along the shielding member 135 to the end in the width direction A2 and is stored in the second storage sections 136a, 136b.

Similarly, the paper dust or dirt that enters the first path 133b from the first gap 131b advances along the first path 133b to the position of the shielding member 135. The paper dust or dirt that advances to the position of the shielding member 135 moves along the shielding member 135 to the end in the width direction A2 and is accommodated in the second accommodation sections 136a, 136b.

Figure 14 is a schematic diagram for explaining the removal of cover 101b. Figure 14 is a schematic diagram of the lower housing 101 from above with cover 101b removed.

14, the cover 101b is provided so as to be detachable from the lower housing 101, i.e., from the medium conveying device 100. This allows the user to remove the cover 101b and easily collect paper dust or garbage from the first storage section 107c, thereby enabling the medium conveying device 100 to improve user convenience.

The cover 101b may be provided so as to cover only the second conveying roller 115 without covering the feed roller 112. The cover 101b may also be formed integrally with the light source frame 108. In either case, the cover 101b may be provided so as to be detachable from the medium conveying device 100.

Figure 15 is a block diagram showing the general configuration of the medium conveying device 100.

In addition to the above-mentioned configuration, the medium conveying device 100 further has a motor 141, an interface device 142, a memory device 150, a processing circuit 160, etc.

The motor 141 has one or more motors, and rotates the feed roller 112, separation roller 113, first conveying roller 114, second conveying roller 115, first discharge roller 118 and/or second discharge roller 119 to convey the medium in response to a control signal from the processing circuit 160. Note that one of the first conveying roller 114 and the second conveying roller 115 may be provided so as to rotate following the other of the first conveying roller 114 and the second conveying roller 115, rather than rotating according to the driving force of the motor 141. Also, one of the first discharge roller 118 and the second discharge roller 119 may be provided so as to rotate following the other of the first discharge roller 118 and the second discharge roller 119, rather than rotating according to the driving force of the motor 141.

The interface device 142 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 142, 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 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.

The storage device 150 includes a memory device such as a RAM (Random Access Memory) or a ROM (Read Only Memory), 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 150 also stores computer programs, databases, tables, etc. used for various processes of the medium conveying device 100. Computer programs may be installed into the storage device 150 from a computer-readable portable recording medium using a known setup program, etc. Portable recording media include, for example, a CD-ROM (compact disc read only memory), a DVD-ROM (digital versatile disc read only memory), etc.

The processing circuit 160 operates based on a program previously stored in the storage device 150. The processing circuit is, for example, a CPU (Central Processing Unit). The processing circuit 160 may be a DSP (digital signal processor), an LSI (large scale integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or the like.

The processing circuit 160 is connected to the operation device 105, the display device 106, the media sensor 111, the lighting device 116, the imaging device 117, the motor 141, the interface device 142, the storage device 150, etc., and controls each of these components. Based on the media signal received from the media sensor 111, the processing circuit 160 performs drive control of the motor 141, irradiation control of the lighting device 116, imaging control of the imaging device 117, etc. The processing circuit 160 acquires an input image from the imaging device 117, and transmits it to the information processing device via the interface device 142.

Figure 16 is a diagram showing the general configuration of the memory device 150 and the processing circuit 160.

As shown in FIG. 16, the memory device 150 stores a control program 151, an image acquisition program 152, etc. Each of these programs is a functional module implemented by software running on a processor. The processing circuit 160 reads each program stored in the memory device 150 and operates in accordance with the read program. In this way, the processing circuit 160 functions as a control unit 161 and an image acquisition unit 162.

Figure 17 is a flowchart showing an example of the operation of the media reading process of the media conveying device 100.

Below, an example of the operation of the media reading process of the media conveying device 100 will be described with reference to the flowchart shown in Figure 17. Note that the flow of the operation described below is executed mainly by the processing circuit 160 in cooperation with each element of the media conveying device 100 based on a program previously stored in the storage device 150.

First, the control unit 161 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 142 (step S101).

Next, the control unit 161 acquires a medium signal from the medium sensor 111, and determines whether or not a medium is placed on the placement table 103 based on the acquired medium signal (step S102). If a medium is not placed on the placement table 103, the control unit 161 ends the series of steps.

On the other hand, if a medium is placed on the placement table 103, the control unit 161 drives the motor 141 (step S103). As a result, the control unit 161 rotates the feed roller 112, the separation roller 113, the first conveying roller 114, the second conveying roller 115, the first discharge roller 118 and/or the second discharge roller 119 to feed and convey the medium.

Next, the control unit 161 causes the lighting device 116 to illuminate the medium while causing the imaging device 117 to capture an image of the medium, acquires an input image from the imaging device 117, and outputs the acquired input image by transmitting it to the information processing device via the interface device 142 (step S104).

Next, the control unit 161 determines whether or not a medium remains on the mounting table 103 based on the medium signal received from the medium sensor 111 (step S105). If a medium remains on the mounting table 103, the control unit 161 returns the process to step S104 and repeats the processes of steps S104 to S105.

On the other hand, if no media remain on the mounting table 103, the control unit 161 stops the motor 141 (step S106). This causes the control unit 161 to stop the feed roller 112, the separation roller 113, the first conveying roller 114, the second conveying roller 115, the first discharge roller 118 and/or the second discharge roller 119, thereby stopping the feeding and conveying of the media. The control unit 161 then ends the series of steps.

As described above in detail, the medium conveying device 100 is provided with first gaps 131a, 131b between the housing frame 107 and the light source frame 108 through which paper dust or dirt can enter, and a second gap 132 for allowing light to enter the housing frame 107. In the medium conveying device 100, a shielding member 135 that blocks the entry of paper dust is provided between the first gaps 131a, 131b and the second gap 132. This makes it possible for the medium conveying device 100 to prevent paper dust or dirt from entering the path of the light received by the optical element.

Figure 18 is a schematic diagram for explaining the first storage section 207c in a medium conveying device according to another embodiment.

The first storage section 207c shown in FIG. 18 is used in place of the first storage section 107c of the medium conveying device 100. The first storage section 207c has a similar configuration to the first storage section 107c. However, the first storage section 207c is provided so as to be detachable from the lower housing 101, i.e., from the medium conveying device. This allows the user to easily remove paper dust or debris contained in the first storage section 207c, and the medium conveying device 100 can improve user convenience.

As described above in detail, the medium conveying device is capable of preventing paper dust or debris from entering the path of the light received by the optical element, even when the first storage section 207c is provided in a removable manner.

Figure 19 is a schematic diagram for explaining the housing frame 307, light source frame 308 and shielding member 335 in a medium conveying device according to another embodiment.

The housing frame 307, light source frame 308 and shielding member 335 shown in Figure 19 are used in place of the housing frame 107, light source frame 108 and shielding member 135 of the medium conveying device 100. The housing frame 307, light source frame 308 and shielding member 335 have the same configuration as the housing frame 107, light source frame 108 and shielding member 135. However, the shielding member 335 is attached to the housing frame 307, not the light source frame 308.

The light source frame 308 has a first rib 308b, a second rib 308c, and a third rib (not shown) that protrude downward, i.e., toward the housing frame 307 side. The first rib 308b, the second rib 308c, and the third rib are arranged to surround the first opening 307b and the second opening 308a and to face the shielding member 335. The first rib 308b is arranged upstream of the first opening 307b and the second opening 308a and has a first plane 308d that is inclined so as to be positioned upward toward the upstream side. The second rib 308c is arranged downstream of the first opening 307b and the second opening 308a and has a second plane 308e that is inclined so as to be positioned upward toward the upstream side. The third rib is arranged at both ends of the width direction A2 of the first opening 307b and the second opening 308a and has a third plane (not shown) that is inclined so as to be positioned upward toward the outside.

The corners of the shielding member 335 are pressed against the first plane 308d, the second plane 308e, and the third plane. As a result, no gaps are generated between the shielding member 335 and the light source frame 308 and the housing frame 307. Therefore, the paper dust or dirt that has entered the first path 133a from the first gap 131a, and the paper dust or dirt that has entered the first path 133b from the first gap 131b are more reliably prevented from entering the second gap 132.

In this case, the portion of the light source frame 308 that comes into contact with the shielding member 335 is preferably mirror-polished or Teflon (registered trademark) coated. This allows the medium transport device to reduce the coefficient of friction between the light source frame 308 and the shielding member 335, and to increase the ratio of the compressive force N by the shielding member 335 to the weight W of the light source frame 308. Therefore, the medium transport device can generate a larger compressive force with a smaller pushing force, and the so-called wedge effect can be enhanced.

As described above in detail, the medium conveying device is capable of preventing paper dust or debris from entering the path of the light received by the optical element, even when the shielding member 335 is attached to the housing frame 307.

Figure 20 is a schematic diagram for explaining a housing frame 407 in a media conveying device relating to another embodiment.

The housing frame 407 shown in FIG. 20 is used in place of the housing frame 107 of the medium conveying device 100. The housing frame 407 has a similar configuration to the housing frame 107. However, the housing frame 407 has a first rib 407e, a second rib 407f, and a third rib (not shown) instead of the first rib 107e, the second rib 107f, and the third rib 107g. The first rib 407e, the second rib 407f, and the third rib have the same configuration as the first rib 107e, the second rib 107f, and the third rib 107g, respectively. The first rib 407e is disposed upstream of the first opening 407b and the second opening 108a, and has a first plane 407h that is inclined so as to be positioned downward toward the upstream side. The second rib 407f is disposed downstream of the first opening 407b and the second opening 108a, and has a second plane 407i that is inclined so as to be positioned downward toward the upstream side. The third ribs are arranged at both ends of the first opening 407b and the second opening 108a in the width direction A2, and have third flat surfaces (not shown) that are inclined so as to be positioned lower toward the outside.

The housing frame 407 further has a fourth rib 407k, a fifth rib 407l, and a sixth rib (not shown). The fourth rib 407k is arranged upstream of the first opening 407b and the second opening 108a, and has a fourth plane 407m that is inclined so as to be positioned upward toward the upstream side. The fifth rib 407l is arranged downstream of the first opening 407b and the second opening 108a, and has a fifth plane 407n that is inclined so as to be positioned upward toward the upstream side. The sixth rib is arranged at both ends of the width direction A2 of the first opening 407b and the second opening 108a, and has a sixth plane (not shown) that is inclined so as to be positioned upward toward the outside. The fourth rib 407k, the fifth rib 407l and the sixth rib are arranged so that the fourth plane 407m, the fifth plane 407n and the sixth plane, respectively, face the first plane 407h of the first rib 407e, the second plane 407i of the second rib 407f and the third plane of the third rib.

The two mutually opposing corners of the shielding member 135 are pressed against the first plane 407h and the fourth plane 407m, respectively. Similarly, the two mutually opposing corners of the shielding member 135 are pressed against the second plane 407i and the fifth plane 407n, respectively, and are pressed against the third plane and the sixth plane. As a result, no gap is generated between the shielding member 135 and the light source frame 108 and the housing frame 407. Therefore, the paper dust or dust that has entered the first path 133a from the first gap portion 131a, and the paper dust or dust that has entered the first path 133b from the first gap portion 131b are more reliably prevented from entering the second gap portion 132. In particular, by pressing the planes against the two mutually opposing corners of the shielding member 135, the forces applied to each corner from each plane are offset, and the medium transport device can stably hold the shielding member 135.

In addition, even when flat surfaces are pressed against two mutually opposing corners of the shielding member 135, the shielding member 135 may be attached to the housing frame 407 instead of the light source frame 108. In other words, the light source frame 108 may be configured to have two flat surfaces against which the two corners of the shielding member 135 are pressed. In this case as well, the medium transport device is able to stably hold the shielding member 135.

As described above in detail, the media conveying device is capable of preventing paper dust or dirt from entering the path of the light received by the optical element, even when flat surfaces are pressed against each of the two opposing corners of the shielding member 135.

Figure 21 is a schematic diagram for explaining the housing frame 507 and the shielding member 535 in a medium conveying device according to another embodiment.

The housing frame 507 and shielding member 535 shown in FIG. 21 are used in place of the housing frame 107 and shielding member 135 of the medium conveying device 100. The housing frame 507 and shielding member 535 have the same configuration as the housing frame 107 and shielding member 135, respectively. However, the housing frame 507 has a first rib 507e, a second rib 507f, and a third rib (not shown) instead of the first rib 107e, the second rib 107f, and the third rib 107g. The first rib 507e, the second rib 507f, and the third rib have the same configuration as the first rib 107e, the second rib 107f, and the third rib 107g, respectively. However, the first rib 507e, the second rib 507f and the third rib each have a rectangular parallelepiped shape, and have a first corner 507h, a second corner 507i and a third corner (not shown) instead of the first plane 107h, the second plane 107i and the third plane 107j.

On the other hand, the shielding member 535 has a first plane 535a that is inclined downward toward the upstream side at a position facing the first corner 507h. Similarly, the shielding member 535 has a second plane 535b that is inclined downward toward the upstream side at a position facing the second corner 507i. In addition, the shielding member 535 has a third plane (not shown) that is inclined downward toward the outside in the width direction A2 at a position facing the third corner.

The first corner 507h, the second corner 507i, and the third corner of the housing frame 507 are pressed against the first plane 535a, the second plane 535b, and the third plane of the shielding member 535, respectively. As a result, the plane of the shielding member 135 is crushed by the first corner 507h, the second corner 507i, and the third corner, and no gap is generated between the shielding member 535 and the light source frame 108 and the housing frame 507. Therefore, the paper powder or dust that has entered the first path 133a from the first gap portion 131a and the paper powder or dust that has entered the first path 133b from the first gap portion 131b are more reliably prevented from entering the second gap portion 132.

Even when the corners of the frame are pressed against the plane of the shielding member 535, the shielding member 535 may be attached to the housing frame 507 instead of the light source frame 108. That is, the light source frame 108 may be provided with a rib having a corner that is pressed against the plane of the shielding member 535. In this case, the medium conveying device can also prevent paper powder or debris from entering the second gap portion 132.

As described above in detail, the media conveying device is able to prevent paper dust or debris from entering the path of the light received by the optical element, even when the corners of the frame are pressed against the flat surface of the shielding member 535.

Figure 22 is a diagram showing a schematic configuration of a processing circuit 660 in a medium conveying device according to yet another embodiment. The processing circuit 660 is used in place of the processing circuit 160 of the medium conveying device 100, and executes media reading processing and the like in place of the processing circuit 160. The processing circuit 660 has a control circuit 661, an image acquisition circuit 662, and the like. Each of these components may be composed of an independent integrated circuit, microprocessor, firmware, and the like.

The control circuit 661 is an example of a control unit, and has the same functions as the control unit 161. The control circuit 661 receives an operation signal from the operation device 105 or the interface device 142, and a medium signal from the medium sensor 111. The control circuit 661 controls the motor 141 based on the received information.

The image acquisition circuit 662 is an example of an image acquisition unit, and has the same function as the image acquisition unit 162. The image acquisition circuit 662 controls the lighting device 116 and the imaging device 117 to acquire an input image from the imaging device 117, and outputs it to the interface device 142.

As described above in detail, the media conveying device is capable of preventing paper dust or debris from entering the path of the light received by the optical element, even when using the processing circuit 660.

100 Media conveying device, 101a Lower guide, 101b Cover, 102a Upper guide, 107, 307, 407, 507 Housing frame, 107a Recess, 107b First opening, 107c First storage section, 107d Fourth opening, 107h, 407h First plane, 107i, 407i Second plane, 107j Third plane, 407m Fourth plane, 407n Fifth plane, 507h First corner, 507i Second corner, 108, 308 Light source frame, 108a Second opening, 308d First plane, 308e Second plane, 115 Second conveying roller, 121 Light source group, 123 Reflecting member group, 124 Lens group, 125 Image sensor, 131a First gap, 132 Second gap, 133a First path, 133c Second path, 134 Third opening, 135, 335, 535 Shielding member, 535a First plane, 535b Second plane, 136a, 136b Second storage section

Claims (14)

a housing frame having a medium guide surface in which a recess having a first opening is formed;
a light source frame disposed in the recess and having a second opening and a light source;
an optical element that receives light that is emitted from the light source, reflected by the medium transported along the medium guide surface, and passes through the first opening and the second opening;
a first gap portion formed between the housing frame and the light source frame;
a second gap portion formed between the first opening and the second opening;
a first path extending from the first gap to the second gap;
A shielding member disposed on the first path;
a storage section for storing the paper dust or dirt shielded by the shielding member ,
The storage section is provided outside the first path.
A medium transport device comprising : a third opening formed between the shielding member and the first gap;
The medium transport device of claim 1 , further comprising a second path for guiding paper dust or dirt that enters through the first gap and is blocked by the blocking member from the third opening to the storage section. The medium conveying device further includes a conveying roller for conveying the medium.
the medium guide surface further has a fourth opening for disposing the transport roller;
The medium transport device according to claim 1 , wherein the storage portion is disposed so as to face the fourth opening portion. The medium transport device according to claim 3, wherein the transport roller is arranged such that, in the medium transport direction, the gap between the upstream end of the transport roller and the upstream wall of the storage section is smaller than the gap between the downstream end of the transport roller and the downstream wall of the storage section. The medium transport device according to claim 3 or 4, wherein the end of the medium guide surface that forms the downstream end of the fourth opening in the medium transport direction has an inclined surface that is positioned downward toward the upstream side. The medium transport device according to any one of claims 1 to 5, wherein the light source frame is detachably provided from the medium transport device. The medium transport device according to any one of claims 1 to 6, wherein the storage section is detachably provided from the medium transport device. The shielding member is made of sponge,
The medium transport device according to claim 1 , wherein the housing frame or the light source frame has a flat surface against which a corner of the shielding member is pressed. The medium transport device according to claim 8, wherein the housing frame or the light source frame has two flat surfaces against which the two corners of the shielding member are pressed. The shielding member is made of sponge,
The medium transport device according to claim 1 , wherein the shielding member has a flat surface against which a corner of the housing frame or the light source frame is pressed. The medium transport device according to any one of claims 1 to 9, further comprising a second storage section arranged at an end of the first path in a width direction perpendicular to the medium transport direction, for storing paper dust or dirt shielded by the shielding member. The medium conveying device according to any one of claims 1 to 11, wherein the first path has a labyrinth structure. The medium transport device according to any one of claims 1 to 12, wherein the portion of the housing frame or the light source frame that comes into contact with the shielding member is mirror-polished or Teflon (registered trademark) coated. The media transport device according to any one of claims 1 to 13, wherein the housing frame forms the media guide surface and has a cover that is detachable from the media transport device.

Images