Image reading device and image forming device

Abstract

To provide an image reader capable of reducing the possibility of damaging a rotation member for detecting a sheet during maintenance of a reading unit and jam processing, and an image forming apparatus provided therewith.SOLUTION: An image forming apparatus 101 includes: a reading unit 307; a rotation guide member 500 supported by a housing 316 so as to be rotatable between a closed position of covering the reading unit 307 when viewed from above and an open position of exposing the reading unit 307 when viewed from above; and a sheet detection unit 600 having a flag member 601 provided in a rotatable manner. The flag member 601 is arranged at a position at which an abutting part 602 is exposed when viewed from above in a state where the rotation guide member 500 is located at the open position. The abutting part 602 has a first inclined plane 602a and a second inclined plane 602b formed so as to mutually come closer to an axial direction as it is separated from a rotary shaft part 603 in an orthogonal direction perpendicular to the axial direction of the rotary shaft part 603.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to an image reading device that reads an image on a sheet and an image forming apparatus including the same. [Background technology]

[0002] Conventionally, image reading devices mounted on image forming devices such as copiers are known to have an automatic document feeder (hereinafter referred to as ADF) that feeds sheets one by one as documents placed on a document tray. When a reading unit that reads images on a sheet is disposed inside such an ADF, the sheet transport path may be configured to be openable so that the glass surface of the reading unit is exposed to the outside of the device in order to clean the glass surface facing the sheet or to handle jams. Patent Document 1 describes a configuration in which an opening / closing member that forms the top surface of the device and a guide member that forms the sheet transport path of the ADF are rotatable in order to expose the glass surface of the reading unit to the outside of the device.

[0003] In addition, some ADFs have a detection unit disposed in the sheet transport path to detect the sheet for transport control and jam detection. A known example of such a detection unit is one that includes a rotating member that rotates when pressed by the transported sheet, and a sensor that detects the sheet by detecting the rotation of the rotating member (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-194011 A [Patent Document 2] JP 2007-22706 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a configuration in which the conveying path can be opened as in Patent Document 1, a rotating member for detecting a sheet may be exposed to the outside of the device when the sheet conveying path is opened. In such a case, there is a risk that the rotating member may be damaged if the operator's hand or a cleaning tool comes into contact with the rotating member during maintenance of the reading unit or when clearing a jam.

[0006] Therefore, an object of the present invention is to provide an image reading device and an image forming apparatus equipped with the same that can reduce the possibility of damage to a rotating member for detecting sheets during maintenance of the reading unit or jam processing. [Means for solving the problem]

[0007] One aspect of the present invention is a document that includes a housing, a placement section on which a sheet is placed, a feeding member that feeds the sheet placed on the placement section, a transport member that transports the sheet fed by the feeding member along a transport path, a reading unit that reads an image on the sheet transported by the transport member, an opening / closing member that has a first guide surface that faces an upper surface of the sheet transported by the transport member and guides the sheet, the opening / closing member being rotatably supported by the housing, and a second guide surface that faces a lower surface of the sheet transported by the transport member and forms the transport path together with the first guide surface, the opening / closing member having a first position that covers the reading unit when viewed from above, and a second position that covers the reading unit when viewed from above. and a detection unit having a rotating member rotatably provided, the rotating member being pressed by a sheet conveyed by the conveying member to rotate and detecting the sheet, the rotating member having a rotating shaft portion and an abutment portion that abuts against the sheet conveyed by the conveying member, the rotating member being disposed at a position where the abutment portion is exposed when viewed from above with the guide member positioned at the second position, the abutment portions being formed to approach each other in the axial direction as they move away from the rotating shaft portion in a direction perpendicular to the axial direction of the rotating shaft portion. , a plane extending in a direction inclined with respect to the perpendicular direction and the axial direction. The image reading device is characterized by having a first surface and a second surface. Effect of the Invention

[0009] According to the present invention, it is possible to provide an image reading device and an image forming apparatus equipped with the same that can reduce the possibility of damage to a rotating member for detecting a sheet during maintenance of the reading unit or when clearing a jam. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view of an image forming apparatus. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. 4 is a perspective view of the ADF with the access cover open. [Diagram 5] FIG. 4 is a perspective view of the ADF with the opening / closing cover and the rotation guide member open. [Figure 6] FIG. 4 is a side view of the ADF with the rotation guide member closed. [Figure 7] FIG. 4 is a side view of the ADF with the rotation guide member open. [Figure 8] FIG. 4 is a cross-sectional view of the reading unit and the reading guide member. [Figure 9] FIG. 4 is a perspective view of the ADF with the opening / closing cover and the rotation guide member open. [Figure 10] FIG. 4 is an enlarged view of the vicinity of a contact portion of the flag member according to the first embodiment. [Figure 11] FIG. 4 is a cross-sectional view of the ADF in the vicinity of the flag member according to the first embodiment. [Figure 12] FIG. 2 is a perspective view of a flag member according to the first embodiment. [Figure 13] FIG. 11 is an enlarged view of the vicinity of a contact portion of a flag member according to a second embodiment. [Figure 14] FIG. 11 is a perspective view of a flag member according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [First embodiment] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. However, the following embodiment is an example of the present invention and does not limit the technical scope of the present invention.

[0012] <Image forming device> First, an image forming apparatus 100 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view of the image forming apparatus 100 as viewed from the front.

[0013] 1, the image forming apparatus 100 includes an image forming apparatus main body 104 and an image reading device 101 provided above the image forming apparatus main body 104. The image forming apparatus 100 forms a toner image on a sheet of paper P in response to image data read by the image reading device 101 or an image signal from a host device such as a personal computer communicatively connected to the image forming apparatus 100. Examples of the sheet of paper P that is a recording medium include sheet materials such as plain paper, plastic film, and cloth.

[0014] Inside the image forming apparatus main body 104, there are provided laser scanners 107-110 corresponding to the respective colors of YMCK, which are image forming sections using an electrophotographic method, image forming units 111-114, and a fixing unit 118. The laser scanners 107-110 irradiate lasers toward the photoconductors of the corresponding image forming units 111-114 in response to input image signals. These image forming units 111-114 are arranged along an intermediate transfer belt 115.

[0015] In the image forming unit 111, a yellow toner image is formed, and the formed yellow toner image is primarily transferred to the intermediate transfer belt 115. In the image forming unit 112, a magenta toner image is formed, and the formed magenta toner image is primarily transferred and superimposed on the yellow toner image transferred to the intermediate transfer belt 115. In the image forming unit 113, a cyan toner image is formed, and the formed cyan toner image is primarily transferred and superimposed on the yellow and magenta toner images transferred to the intermediate transfer belt 115. In the image forming unit 114, a black toner image is formed, and the formed black toner image is primarily transferred and superimposed on the yellow, magenta, and cyan toner images transferred to the intermediate transfer belt 115.

[0016] A paper feed cassette 105 is disposed at the bottom of the image forming apparatus main body 104 so as to be able to be pulled out toward the front side. The image forming apparatus 100 feeds paper P stored in the paper feed cassette 105 by a pickup roller 106 toward a secondary transfer nip portion where an intermediate transfer belt 115 and a secondary transfer unit 116 come into contact with each other. When conveying the paper P, the image forming apparatus 100 conveys the paper P in synchronization with the toner image on the intermediate transfer belt 115. Then, the multiple toner image on the intermediate transfer belt 115 is transferred onto the paper P at the secondary transfer nip portion by the action of a secondary transfer bias voltage applied to the secondary transfer unit 116.

[0017] The paper P onto which the toner image has been secondarily transferred by the secondary transfer section 116 is transported by a transport belt 117 to a fixing unit 118. The paper P is then heated and pressurized by the fixing unit 118 to fix the toner image thereon, and is then discharged onto a paper output tray 119 after the toner image has been fixed onto the surface of the paper P.

[0018] In this embodiment, the image forming apparatus 100 includes an electrophotographic image forming means, but the image forming means is not limited to this, and may be other image forming means such as an inkjet type.

[0019] <Image reader> Next, the image reading device 101 will be described with reference to FIGS. 2 and 3. FIG. 2 is a perspective view of the image reading device 101, and FIG. 3 is a schematic cross-sectional view of the image reading device 101. The image reading device 101 has a reader 103 and an ADF 102 provided on the upper part of the reader 103. The image reading device 101 also has a control unit 101a, which controls the conveyance of the sheet by the ADF 102 based on a signal from a sheet detection unit 600 described later. The ADF 102 is supported rotatably with respect to the reader 103 by a hinge (not shown) provided at the rear side of the device. The image reading device 101 can execute an operation of reading image information from a stationary original placed on an original table glass 318 of the reader 103 (fixed reading operation) and an operation of reading image information while conveying a sheet as an original by the ADF 102 (flick reading operation).

[0020] 3, the reader 103 includes a platen glass 318 on which an original is placed, and a reading unit 306 that reads image information of the original placed on the platen glass 318 while moving in the sub-scanning direction (left-right direction in the figure) below the platen glass 318. The reader 103 also includes a first running reading glass 312. While stopped below the first running reading glass 312, the reading unit 306 can optically scan the original conveyed by the ADF 102 via the first running reading glass 312 to read image information.

[0021] The reading unit 306 has a sensor board 309 on which a CCD image sensor is mounted as a light receiving element, a light source 310 that irradiates the original with light, and a plurality of mirrors 308 that guide the light reflected from the original to the imaging surface of the light receiving element.

[0022] The ADF 102 has a document tray 200, a discharge tray 201 disposed below the document tray 200, and a reading unit 307. In the ADF 102, a feed roller 300, a separation roller pair 301, conveying roller pairs 302, 303, 304, and a discharge roller pair 305 are disposed along a sheet conveying path P1 along which a sheet is conveyed. The document tray 200 is a placement section on which a sheet as a document is placed, and the discharge tray 201 is a discharge stacking section on which a sheet from which image information has been read is discharged. The conveying roller pairs 303, 304 and the discharge roller pair 305 as conveying members are rotatably supported inside a housing 316 including the exterior and sheet metal of the ADF 102. The document tray 200 is configured to be rotatable about a rotation axis (not shown) relative to the housing 316, and a user can easily take out a document on the discharge tray 201 by rotating the document tray 200 upward.

[0023] The reading unit 307 has a contact image sensor (hereinafter, referred to as CIS 311) as a reading section, and a second flow reading glass 313. The second flow reading glass 313 is a first transparent member that transmits light from the original, and the CIS 311 reads image information of the original transported on the sheet transport path P1 via the second flow reading glass 313. The reading unit 307 is rotatably supported on a housing 316 of the ADF 102 via a rotation shaft 314.

[0024] When a user sets a stack of documents on the document tray 200 and issues an instruction to start a reading operation via an operation unit (not shown), the documents are fed to the sheet conveying path P1 in order from the top document by a feeding roller 300 as a feeding member. The fed documents are separated one by one by a separation roller pair 301, and conveyed to the sheet conveying path P1 while being transferred in order to conveying roller pairs 302, 303, and 304. Then, when the documents pass through a first moving reading glass 312, image information of a first surface (front surface) of the documents is read by a reading unit 306. Similarly, when the documents pass through a second moving reading glass 313, image information of a second surface (back surface) opposite to the first surface of the documents is read by a reading unit 307. The documents from which image information has been read are discharged to the outside of the ADF 102 by a discharge roller pair 305 as a discharge member, and are stacked on the discharge tray 201. It should be noted that the first side of the document refers to the upper side of the document when placed on document tray 200, and the second side of the document refers to the lower side of the document when placed on document tray 200.

[0025] The ADF 102 includes an opening / closing cover 315 that constitutes the upper surface of the device. The opening / closing cover 315 as an opening / closing member is supported by a housing 316 of the ADF 102 via a rotation shaft 319 so as to be rotatable (openable and closable). The opening / closing cover 315 is provided with an upper guide 315a that forms a sheet conveying path P1 together with a lower guide 500a of a rotating guide member 500 described later. Here, the upper guide 315a is a first guide surface that faces the upper surface of the sheet fed by the feed roller 300 to guide the sheet. The lower guide 500a is a second guide surface that faces the lower surface of the sheet fed by the feed roller 300 to guide the sheet. The opening / closing cover 315 is fixed to the housing 316 by a lock mechanism (not shown) at the closed position (position shown in FIG. 2). When a user opens the opening / closing cover 315, the user pulls up an opening / closing lever 315b to release the lock mechanism (not shown) and the opening / closing cover 315 can be opened.

[0026] When the opening / closing cover 315 is closed, the upper side of the rotating guide member 500 is covered by the opening / closing cover 315. Also, the opening / closing cover 315 is provided with the feed roller 300, the pair of separation rollers 301, and one roller (upper side in the figure) of the pair of conveying rollers 302. Therefore, when the opening / closing cover 315 rotates upward from the closed position to the open position, a part of the sheet conveying path P1 is opened and the rotating guide member 500 is exposed to the outside of the ADF 102, and the rotating guide member 500 becomes capable of rotating as described later.

[0027] <Glass cleaning> While the image reading device 101 repeats the flow-reading operation, foreign matter such as dust such as paper powder and stains such as glue and ink that were attached to the original may adhere to the first flow-reading glass 312 and the second flow-reading glass 313. If the flow-reading operation is performed with foreign matter attached within the reading range of the reading units 306, 307 on the first flow-reading glass 312 and the second flow-reading glass 312, a streaky image that does not actually exist on the original will be read at the position corresponding to the foreign matter. This is a phenomenon (hereinafter referred to as image streaks) that occurs when the foreign matter attached to the first flow-reading glass 312 and the second flow-reading glass 313 blocks the optical path during reading by the reading units 306, 307, creating a shadow.

[0028] In order to eliminate the occurrence of image streaks, it is effective to properly clean the first and second running glasses 312 and 313 to remove the foreign matter that is the cause. As for the reading unit 306 of the reader 103, the first running glass 312 is exposed by rotating the ADF 102 upward from the reader 103, so that the user can clean it from above. On the other hand, the reading unit 307 of the ADF 102 is disposed inside the housing 316. As shown in FIG. 3, in this embodiment, the reading unit 307 is disposed below the rotating guide member 500 and in an area inside the sheet conveying path P1 curved in a U-shape. Therefore, a configuration for exposing the second running glass 313 to the outside of the device (a means for enabling access to the second running glass 313) is required. Therefore, in this embodiment, the rotation guide member 500 and the reading unit 307 are each configured to be rotatable with respect to the housing 316, making it possible to expose the second running glass 313 of the reading unit 307 to the outside of the ADF .

[0029] Fig. 4 is a perspective view of image reading device 101 with opening / closing cover 315 open. Fig. 5 is a perspective view of image reading device 101 with opening / closing cover 315 and pivot guide member 500 open. As described above, when opening / closing cover 315 is closed, opening / closing cover 315 covers the upper side of pivot guide member 500. On the other hand, as shown in Fig. 4, when opening / closing cover 315 is open, a part of sheet transport path P1 is opened and pivot guide member 500 is exposed to the outside of the device when viewed from above.

[0030] In this embodiment, the rotating guide member 500 is rotatably supported by the housing 316 of the ADF 102 via a rotating shaft 502 extending in a width direction perpendicular to the sheet conveying direction. Here, the width direction is a direction along the main scanning direction of the reading units 306 and 307. The rotating guide member 500 is rotatable between a closed position (position shown in FIG. 4, first position) that covers the reading unit 307 when viewed from above, and an open position (position shown in FIG. 5, second position) that exposes the reading unit 307 to the outside of the device when viewed from above. On the other hand, a fixed guide member 507 that guides a sheet continuously to the lower guide 500a of the rotating guide member 500 is fixed to the housing 316 of the ADF 102. As shown in FIG. 4, the fixed guide member 507 is a guide surface that is adjacent to the downstream end of the lower guide 500a and faces the upper guide 315a to form the sheet conveying path P1.

[0031] The reading unit 307 is configured to rotate in conjunction with the rotation of the rotating guide member 500. FIG. 6 is a side view of the ADF 102 when the rotating guide member 500 is in a closed state, and FIG. 7 is a side view of the ADF 102 when the rotating guide member 500 is in an open state. Note that parts not necessary for the description are omitted in FIG. 6 and FIG. 7. The ADF 102 has an arm member 501 for rotating the reading unit 307. The arm member 501 as an interlocking member is provided so as to be rotatable about a rotation shaft 502 as the rotating guide member 500 rotates. When the user rotates the rotating guide member 500 in the direction of the arrow A, the arm member 501 also rotates in the direction of the arrow A. When the arm member 501 rotates by a predetermined angle, the arm member 501 abuts against the reading unit 307. Then, the reading unit 307 is lifted by the arm member 501 and rotates about the rotation shaft 314 in the direction of arrow B. By the above operation, the second running glass 313 of the reading unit 307 is exposed to the outside of the ADF 102, and the user can clean the second running glass 313 with a cleaning tool such as nonwoven fabric. Furthermore, when the rotation guide member 500 is in the open state and the reading unit 307 has rotated, the user can also clean the protective glass 404, which will be described later.

[0032] <Reading unit configuration> Next, the configuration of the reading unit 307 will be described in detail with reference to Fig. 8. Fig. 8 is a cross-sectional view of the reading unit 307 and the reading guide 403. The reading unit 307 has a first case member 400 and a second case member 401, and the CIS 311 is stored by the first case member 400 and the second case member 401. An opening 402 is provided on the surface of the first case member 400 on the sheet conveying path P1 side to read image information of the conveyed sheet, and a second running reading glass 313 is attached to the first case member 400 so as to cover the opening 402.

[0033] Meanwhile, a reading guide 403 is provided at a position facing the second running reading glass 313. The reading guide 403 is fixed to the housing 316, and has a guide surface that faces the second running reading glass 313 and guides a sheet. The reading guide 403 is provided with a white sheet 405 and a protective glass 404. The white sheet 405 is a white reference member for performing shading correction of the CIS 311 before the reading unit 307 reads the image information of the document. The protective glass 404 is a second transparent member for preventing the surface of the white sheet 405 from being scratched.

[0034] <Sheet detection unit> Next, the sheet detection unit 600 will be described. Fig. 9 is a perspective view of the ADF 102 with the opening / closing cover 315 and the rotating guide member 500 in the open state and with the reading unit 307 rotated, and is a drawing of the ADF 102 in the state shown in Fig. 5, viewed from a different angle. Fig. 10 is an enlarged view of the vicinity of the abutment portion 602 of the flag member 601. Fig. 11 is a cross-sectional view of the vicinity of the flag member 601 of the ADF 102. Fig. 12 is a perspective view of the sheet detection unit 600.

[0035] The ADF 102 has a sheet detection unit 600 as a detection unit for detecting a conveyed sheet. The sheet detection unit 600 is a discharge sensor that detects a sheet at a detection position between the reading position of the reading unit 307 and the pair of discharge rollers 305 in the sheet conveying path P1. As shown in FIG. 12, the sheet detection unit 600 has a flag member 601 which is a rotating member that rotates when pressed by the conveyed sheet, and a photointerrupter 610 which is a sensor that detects the rotation of the flag member 601. The flag member 601 has a rotation shaft portion 603 extending in the main scanning direction, a contact portion 602 formed so as to extend from the rotation shaft portion 603 in an orthogonal direction D that is orthogonal to the axial direction C (main scanning direction), a light shielding portion 604, and flange portions 605 and 606. The contact portion 602 comes into contact with the sheet conveyed in the sheet conveying path P1. The light blocking portion 604 blocks the optical path between the light emitting portion 611 and the light receiving portion 612 of the photointerrupter 610. The flange portions 605 and 606 restrict the movement of the flag member 601 in the main scanning direction by abutting against a restricting portion (not shown) provided on the housing 316. The photointerrupter 610 switches between ON / OFF of a signal to be transmitted to the control portion 101a depending on whether the optical path is blocked by the light blocking portion 604 of the flag member 601 or not.

[0036] 11, the ADF 102 has transport guides 508 and 509 that form a sheet transport path P1 between the reading unit 307 and the pair of discharge rollers 305. The transport guide 508 is a fourth guide surface provided adjacent to the downstream side of the protective glass 404 in the transport direction, and is a guide surface that guides the sheet while facing a first surface opposite to the second surface of the sheet read by the reading unit 307. On the other hand, the transport guide 509 is a third guide surface provided on the opposite side to the lower guide 500a of the rotating guide member 500, and is positioned so as to face the transport guide 508 when the rotating guide member 500 is in the closed state.

[0037] The flag member 601 is disposed so that the contact portion 602 protrudes from the opening 508a formed in the conveying guide 508 into the sheet conveying path P1. When the opening / closing cover 315 and the rotating guide member 500 are in the open state, the flag member 601 is disposed at a position where the contact portion 602 is exposed to the outside of the ADF 102 as viewed from above. The contact portion 602 is disposed on the downstream side of the protective glass 404 in the conveying direction. The leading edge of the sheet conveyed by the conveying roller pair 304 comes into contact with the contact portion 602 after passing the reading position of the reading unit 307. As shown in FIG. 11, the contact portion 602 is pressed by the sheet and rotates around the rotating shaft portion 603 so as to fall to the downstream side in the conveying direction. At this time, the rotating shaft portion 603 rotates, so that the light blocking portion 604 of the flag member 601 moves to a position where it does not block the optical path of the photointerrupter 610. This switches the output signal of the photointerrupter 610, enabling the sheet detection unit 600 to detect the sheet.

[0038] Next, the shape of the contact portion 602 will be described. As shown in FIG. 12, the contact portion 602 is formed with a first inclined surface 602a (first surface) and a second inclined surface 602b (second surface) extending in the direction along the conveying direction. The first inclined surface 602a and the second inclined surface 602b are planes inclined with respect to both the axial direction C and the orthogonal direction D, and are inclined so as to approach each other in the axial direction C as they move away from the rotating shaft portion 603 in the orthogonal direction D. Furthermore, the contact portion 602 is formed with a connection surface 602c that smoothly connects the first inclined surface 602a and the second inclined surface 602b on the upstream side in the conveying direction of the first inclined surface 602a and the second inclined surface 602b. The connection surface 602c is a surface of the contact portion 602 that the sheet comes into contact with. The connection surface 602c is composed of a curved surface portion continuing from the upstream side of the first inclined surface 602a, a curved surface portion continuing from the upstream side of the second inclined surface 602b, and a flat surface portion continuing from these two curved surface portions. Since the first inclined surface 602a and the second inclined surface 602b are inclined so as to approach each other as they move away from the rotating shaft portion 603, the width of the connection surface 602c in the axial direction C becomes smaller as they move away from the rotating shaft portion 603. In other words, the abutting portion 602 has a shape that tapers toward the tip, and the shape of the abutting portion 602 is approximately triangular when viewed from the conveying direction.

[0039] Incidentally, as shown in FIG. 9, when the opening / closing cover 315 and the rotating guide member 500 are in the open state, the flag member 601 is disposed at a position where the abutting portion 602 is exposed to the outside of the ADF 102 as viewed from above. As described above, when the opening / closing cover 315 and the rotating guide member 500 are in the open state, the user can clean the second running glass 313 and the protective glass 404. For example, the user cleans the second running glass 313 and the protective glass 404 by pressing the nonwoven fabric against the area to be cleaned and moving it in the main scanning direction. At this time, the user's hand may come into contact with the abutting portion 602 of the flag member 601. However, in this embodiment, when a force in the main scanning direction is applied to the first inclined surface 602a or the second inclined surface 602b, the flag member 601 rotates in the same direction as when the sheet is detected. In other words, the flag member 601 is configured to be retractable when a force in the direction along the axial direction C is applied to the abutting portion 602. This makes it possible to reduce the possibility of the flag member 601 being damaged when the user cleans the second scanning glass 313 or the protective glass 404.

[0040] In this embodiment, the first inclined surface 602a and the second inclined surface 602b are flat surfaces, but the first inclined surface 602a and the second inclined surface 602b may have a shape other than a flat surface, such as a curved surface.

[0041] [Second embodiment] Next, a second embodiment of the present invention will be described with reference to Fig. 13 and Fig. 14. The second embodiment has a configuration in which only the shape of the abutting portion 602 of the flag member 601 is changed from that of the first embodiment, and therefore, a description of the same configuration as the first embodiment will be omitted.

[0042] 14 shows a flag member 701 as a rotating member of a sheet detection unit 600 according to the second embodiment. The flag member 701 has a rotation shaft portion 703 extending in the main scanning direction, a contact portion 702 extending in an orthogonal direction D perpendicular to an axial direction C of the rotation shaft portion 703, a light shielding portion 704, and flange portions 705 and 706. The contact portion 702 contacts a sheet conveyed in the sheet conveying path P1. The light shielding portion 704 blocks an optical path between a light emitting portion 611 and a light receiving portion 612 of the photointerrupter 610. The flange portions 705 and 706 contact a regulating portion (not shown) provided on the housing 316 to regulate the movement of the flag member 701 in the main scanning direction.

[0043] The contact portion 702 is formed with a first inclined surface 702a (first surface) and a second inclined surface 702b (second surface) extending in the perpendicular direction D. As shown in FIG. 13, the first inclined surface 702a and the second inclined surface 702b are flat surfaces inclined with respect to the conveying direction, and are inclined so as to approach each other toward the upstream side in the conveying direction. Furthermore, the contact portion 702 is formed with a connection surface 702c that smoothly connects the first inclined surface 702a and the second inclined surface 702b on the upstream side of the conveying direction of the first inclined surface 702a and the second inclined surface 702b. The connection surface 702c is a surface of the contact portion 702 that the sheet comes into contact with. The connection surface 702c is composed of a curved surface portion continuing from the upstream side of the first inclined surface 702a, a curved surface portion continuing from the upstream side of the second inclined surface 702b, and a flat surface portion continuing from the two curved surface portions. When viewed from the orthogonal direction D, the shape of the abutting portion 702 is substantially triangular.

[0044] 13, when the opening / closing cover 315 and the rotation guide member 500 are in the open state, the flag member 701 is disposed at a position where the contact portion 702 is exposed to the outside of the ADF 102 when viewed from above. In this configuration, when a force in the main scanning direction is applied to the first inclined surface 702a or the second inclined surface 702b, the flag member 701 rotates in the same direction as when a sheet is detected. This makes it possible to reduce the possibility of the flag member 701 being damaged when the user cleans the second running glass 313 or the protective glass 404, as in the first embodiment. [Explanation of symbols]

[0045] 100 Image forming device 101 Image reading device 102 ADF 103 Leader 306,307 Reading unit 312 First skimming glass 313 Second Skimming Glass 315 Opening and closing cover 500 Rotating guide member 600 Sheet Detection Unit 601,701 Flag parts 602,702 Contact part 602a,702a 1st slope 602b,702b 2nd slope

Claims

1. A housing and a placement section on which a sheet is placed; a feeding member that feeds the sheet placed on the sheet placement section; a conveying member that conveys the sheet fed by the feeding member along a conveying path; a reading unit that reads an image on the sheet conveyed by the conveying member; an opening / closing member having a first guide surface that faces an upper surface of the sheet conveyed by the conveying member and guides the sheet, the opening / closing member being rotatably supported by the housing; a guide member that faces a lower surface of a sheet transported by the transport member, has a second guide surface that forms the transport path together with the first guide surface, and is supported by the housing so as to be rotatable between a first position that covers the reading unit when viewed from above and a second position that exposes the reading unit when viewed from above; a detection unit having a rotating member that is rotatably provided, the rotating member being pressed by the sheet conveyed by the conveying member to rotate and detect the sheet; Equipped with the rotating member has a rotating shaft portion and a contact portion that contacts the sheet conveyed by the conveying member, and is disposed at a position where the contact portion is exposed when viewed from above in a state where the guide member is located at the second position, The abutment portion has a first surface and a second surface which are flat surfaces extending in a direction inclined with respect to the orthogonal direction and the axial direction of the rotation shaft portion and which are formed so as to approach each other in the axial direction as the abutment portion moves away from the rotation shaft portion in the orthogonal direction perpendicular to the axial direction of the rotation shaft portion.

1. An image reading apparatus comprising:

2. the contact portion has a connection surface that connects the first surface and the second surface on an upstream side in a conveying direction and comes into contact with the sheet conveyed by the conveying member, The width of the connection surface in the axial direction becomes smaller as the connection surface moves away from the rotation shaft portion in the orthogonal direction.

2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

3. The detection unit has a sensor having a light emitting unit and a light receiving unit, The rotating member has a light blocking portion that blocks an optical path between the light emitting portion and the light receiving portion.

2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

4. a discharge member that discharges the sheet on which the image has been read by the reading unit, the detection section detects the sheet at a detection position between a reading position of the reading unit on the transport path and the discharge member; 2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

5. the reading unit has a transparent member that transmits light from the sheet, and is rotatable so that the transparent member is exposed when viewed from above with the guide member located at the second position.

2. The image reading apparatus according to claim 1, wherein the image reading apparatus comprises:

6. the transparent member is a first transparent member, the housing has a white reference member for the reading unit to perform shading correction, and a second transparent member that covers the white reference member with respect to the transport path, the rotating member is disposed such that the abutting portion is located downstream of the second transparent member in a sheet conveying direction.

6. The image reading apparatus according to claim 5,

7. the guide member has a third guide surface that guides a sheet on an opposite side to the second guide surface, the housing has a fourth guide surface that is provided adjacent to the second transparent member on a downstream side in the sheet transport direction and that forms the transport path together with the third guide surface; The contact portion is disposed so as to protrude into the transport path from an opening formed in the fourth guide surface.

7. The image reading apparatus according to claim 6,

8. a linking member that rotates the reading unit in conjunction with the rotation of the guide member; 6. The image reading apparatus according to claim 5,

9. An image reading device according to any one of claims 1 to 8, and an image forming unit for forming an image on a recording medium based on the image read by the reading unit.

1. An image forming apparatus comprising:

Images