Image reading device and image forming device

Abstract

This reduces the impact the reading unit receives when it is moved. [Solution] The image reading device comprises a cover unit that is rotatable around a first pivot axis and forms the upper surface of the image reading device, a sheet transport means for transporting sheets, a transport guide for guiding sheets transported by the sheet transport means, which is rotatable around a second pivot axis different from the first pivot axis, a transparent member, and a reading unit having a reading section for reading images of sheets transported by the sheet transport means through the transparent member, which is rotatable around a third pivot axis different from the first and second pivot axes, and the transparent member is exposed to the outside of the image reading device as the cover unit, transport guide and reading unit rotate.

Description

Technical Field

[0001] The present disclosure relates to an image reading apparatus that reads image information from a sheet, and an image forming apparatus that forms an image on a recording material.

Background Art

[0002] Conventionally, in image reading apparatuses installed in copiers and the like, there is known an apparatus in which a reading unit is disposed inside an automatic document conveying apparatus (hereinafter referred to as ADF) that conveys documents while separating the documents one by one. When the reading unit is disposed inside the ADF, the reading unit may be configured to be movable so that the glass surface facing the document is exposed, for purposes such as cleaning the glass surface and clearing document jams. Patent Document 1 describes a configuration in which a reading unit disposed inside an ADF is supported by a conveyance guide that forms a document conveyance path, and when the conveyance guide is rotated, the reading unit rotates integrally with the conveyance guide.

Prior Art Literature

Patent Documents

[0003]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0004] However, in the configuration described in the above document, the reading unit rotates integrally with the conveyance guide, so when the conveyance guide abuts against another member, an impact corresponding to the total weight of the rotatable unit including the reading unit and the conveyance guide is generated. The reading unit is a precision apparatus equipped with electronic circuits and optical elements inside, and there is a possibility that internal components may be damaged or misaligned when a large impact is applied, so it has been desired to reduce the impact received by the reading unit.

[0005] Therefore, the present invention aims to provide an image reading device capable of reducing the impact received by the reading unit when the reading unit is moved, and an image forming device equipped therewith. [Means for solving the problem]

[0006] One aspect of the invention according to the present disclosure is an image reading device for reading image information from a sheet, comprising: a cover unit rotatably mounted around a first pivot axis and constituting the upper surface of the image reading device; a sheet transport means for transporting the sheet along a sheet transport path; a transport guide for guiding the sheet transported by the sheet transport means, the transport guide being rotatably mounted around a second pivot axis different from the first pivot axis; a transparent member; and a reading unit for reading an image of the sheet transported by the sheet transport means through the transparent member, wherein the first pivot axis The image reading device comprises a reading unit rotatably mounted around a third pivot axis different from the axis and the second pivot axis, and an interlocking mechanism that rotates the reading unit in conjunction with the rotation of the transport guide, wherein the cover unit is rotatable between a closed position that forms part of the sheet transport path together with the transport guide and an open position that opens part of the sheet transport path, and when the cover unit is in the open position, the reading unit rotates in conjunction with the transport guide by the interlocking mechanism, thereby exposing the transparent member to the outside of the image reading device. [Effects of the Invention]

[0007] According to this disclosure, the impact received by the reading unit when it is moved can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] Schematic diagram (a) of an image forming apparatus and schematic diagram (b) of a document reading apparatus according to an embodiment. [Figure 2] A diagram showing a part of the ADF according to Example 1. [Figure 3]A cross-sectional view of the reading unit and its surroundings according to Example 1. [Figure 4] Cross-sectional view of the reading unit and its surroundings at the cutting position shown in Figure 2. [Figure 5] Figures (a, b) illustrating the movement of the rotating guide and reading unit according to Example 1. [Figure 6] This figure shows the reading unit according to Example 1 in a state where it has been moved to the maintenance position. [Figure 7] A schematic diagram illustrating the force acting from the arm to the reading unit. [Figure 8] A schematic diagram illustrating the maximum rotation angle when the arm contacts only one surface of the reading unit. [Figure 9] A diagram showing a portion of the ADF related to a modified version. [Figure 10] A diagram showing a portion of the ADF according to Example 2. [Figure 11] A diagram showing a portion of the ADF according to Example 2. [Figure 12] A diagram showing a portion of the ADF according to Example 2. [Figure 13] A diagram showing a portion of the ADF according to Example 3. [Figure 14] A diagram showing a portion of the ADF according to Example 3. [Figure 15] A diagram showing a portion of the ADF according to Example 4. [Figure 16] A diagram showing a portion of the ADF related to a modified version. [Figure 17] Figures (a-c) show the wires connected to the reading unit in Example 1. [Figure 18] A diagram showing a portion of the ADF according to Example 5. [Figure 19] A diagram showing a portion of the ADF according to Example 5. [Figure 20] A diagram showing a part of the ADF according to Example 6. [Figure 21] A diagram showing a part of the ADF according to Example 6. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

[0010] [Image Forming Apparatus] First, a schematic configuration of an image forming apparatus 1 according to the present embodiment will be described with reference to FIG. 1(a). The image forming apparatus 1 of the present embodiment is a color electrophotographic apparatus including, as an image forming unit, an image forming mechanism 1B that includes four image forming portions PY, PM, PC, and PK. The image forming apparatus 1 forms an image on a sheet S based on image information received from a document reading device 2 provided at an upper portion of an apparatus main body 1A or an external device. As the sheet S which is a recording material, various sheet materials different in size and material can be used, such as paper including plain paper and thick paper, plastic film, cloth, sheet materials subjected to surface treatment such as coated paper, and sheet materials of special shapes such as envelopes and index paper.

[0011] The image forming apparatus 1 includes a main control unit 12. The main control unit 12 includes a CPU as an execution unit for a control program of the image forming apparatus 1, a ROM that stores the program, a RAM that temporarily stores data, and an input / output circuit that inputs and outputs signals to and from the outside. The CPU reads and executes the program from the ROM, and sends commands to each unit of the image forming apparatus 1 via the input / output circuit, thereby controlling the operation of the image forming apparatus 1. For example, the main control unit 12 is electrically connected to a control unit 2C of the document reading device 2. The main control unit 12 can perform an image forming operation (copying) of receiving, via the control unit 2C of the document reading device 2, image information read from a document by reading units 110 and 210, and forming an image on the sheet S based on the received image information.

[0012] The image forming units PY, PM, PC, and PK are units that form yellow, magenta, cyan, and black toner images, respectively. The image forming units PY to PK are also called process units or image forming stations. The four image forming units PY, PM, PC, and PK have substantially the same configuration except that they use different toner colors to create the toner images. Each image forming unit PY to PK has a photosensitive drum 3, which is an electrophotographic photoreceptor formed in a drum shape, and a charging device 4, a developing device 6, and a drum cleaner 8, which are process means that act on the photoreceptor to perform the electrophotographic process. Below the image forming units PY to PK, an exposure device 5 is positioned as a process means (exposure means) for exposing the photosensitive drum 3 of each image forming unit PY to PK. Above the image forming units PY to PK, a replenishment container 9 for replenishing developer to the developing device 6 of each image forming unit PY to PK is detachably attached to the main body 1A of the device.

[0013] An intermediate transfer unit 19 is positioned above the image forming sections PY to PK. The intermediate transfer unit 19 includes an intermediate transfer belt 21, which is an intermediate transfer body made of an endless flexible member, and a plurality of rollers that tension the intermediate transfer belt 21. The plurality of rollers include a secondary transfer inner roller 22. On the outer circumference of the intermediate transfer belt 21, a secondary transfer roller 23 is positioned opposite the secondary transfer inner roller 22, with the intermediate transfer belt 21 in between. A transfer section (secondary transfer section T2) is formed as a nip between the secondary transfer roller 23 and the secondary transfer inner roller 22, where the image is transferred from the intermediate transfer belt 21 to the sheet S. On the inner circumference of the intermediate transfer belt 21, primary transfer rollers 7 are positioned opposite each photosensitive drum 3, with the intermediate transfer belt 21 in between. A belt cleaner 24 is also positioned on the outer circumference of the intermediate transfer belt 21.

[0014] A sheet feeding unit for feeding sheets S is provided at the lower part of the main body 1A of the apparatus. The sheet feeding unit includes a cassette 40 that is detachably attached to the main body 1A of the apparatus, and a feeding unit that feeds the sheets S stored in the cassette 40 one by one while separating them. A transport roller 41 and a registration roller 42 are arranged on the transport path from the sheet feeding unit to the secondary transfer unit T2.

[0015] A fixing device 30 is positioned downstream of the secondary transfer section T2 in the sheet transport direction. The fixing device 30 includes a fixing roller 31 as a heating element, a pressure roller 32 as a pressure element, and a heating means (not shown) for heating the fixing roller 31. A halogen lamp or an electromagnetic induction heating unit can be used as the heating means. Further downstream of the fixing device 30, a discharge roller 43 is positioned as a discharge means for discharging the image-formed sheet S to the outside of the device body 1A. A discharge tray 11 is provided on the upper surface of the device body 1A as a loading section on which the image-formed sheets S are loaded. This embodiment employs a so-called in-body discharge type configuration in which a space is provided between the device body 1A and the document reading device 2 in the vertical direction (vertical direction when the image forming apparatus 1 is installed on a horizontal plane) for discharging and loading the image-formed sheet S.

[0016] When the main control unit 12 receives image information and instructions to execute image forming operations, the main control unit 12 executes the image forming operations as follows: First, the photosensitive drums 3 start rotating in the image forming units PY to PK, and the surface of the photosensitive drums 3 is uniformly charged to a predetermined polarity and potential by the charging device 4. The exposure device 5 irradiates each photosensitive drum 3 with laser light modulated according to the image signal (video signal) based on the image information, and writes electrostatic latent images corresponding to the component images of each color (yellow, magenta, cyan, and black) onto the photosensitive drums 3. These electrostatic latent images are developed by the developing device 6 using a developer containing toner of each color, and toner images of yellow, magenta, cyan, and black are created on the photosensitive drums 3. The toner images carried on each photosensitive drum 3 are first transferred from the photosensitive drums 3 to the intermediate transfer belt 21 by the primary transfer roller 7. At this time, the toner images of each color overlap each other on the intermediate transfer belt 21, forming a full-color toner image on the intermediate transfer belt 21. Any residue such as leftover toner that remains on the surface of the photosensitive drum 3 without being transferred to the intermediate transfer belt 21 is removed by the drum cleaner 8. The image formed on the intermediate transfer belt 21 is transported to the secondary transfer section T2 by the rotation of the intermediate transfer belt 21.

[0017] In parallel with the toner image creation process in the image forming section PY~PK, one sheet S is fed from the cassette 40 and transported to the registration roller 42 via the transport roller 41. The registration roller 42 corrects the skew of the sheet S and then transports the sheet S to the secondary transfer section T2 so that the arrival of the image supported on the intermediate transfer belt 21 to the secondary transfer section T2 and the arrival of the sheet S to the secondary transfer section T2 are synchronized. In the secondary transfer section T2, a bias voltage is applied to the secondary transfer roller 23, thereby transferring the image from the intermediate transfer belt 21 to the sheet S (secondary transfer). Any adhering material that remains on the intermediate transfer belt 21 without being transferred to the sheet S is removed by the belt cleaner 24.

[0018] The sheet S, having passed through the secondary transfer section T2, is transported to the fixing device 30. The fixing device 30 heats and pressurizes the image on the sheet S while gripping and transporting it with a nip section (fixing nip) between the fixing roller 31 and the pressure roller 32. As a result, the toner melts, mixes, and then fixes, resulting in an image fixed to the sheet S. The sheet S, having passed through the fixing device 30, is discharged by the discharge roller 43 and loaded onto the discharge tray 11. This completes the series of image forming operations.

[0019] In this embodiment, an intermediate transfer type color electrophotographic apparatus is illustrated, but the image forming apparatus 1 may also include a direct transfer type image forming means that transfers the toner image formed on the image carrier to the sheet S without going through an intermediate transfer body. Furthermore, the image forming apparatus 1 is not limited to an electrophotographic method and may also include an inkjet printing unit or an offset printing mechanism as image forming means.

[0020] [Document scanning device] An example of an image reading device, the document reading device 2, will be explained using Figure 1(b). The document reading device 2 includes a scanner unit 20 (main body and lower unit) and an ADF 10, which is an upper unit provided above the scanner unit 20 and rotatably supported by the scanner unit 20. The document reading device 2 is capable of performing two operations: reading image information from a stationary document placed on the document glass of the scanner unit 20 (fixed reading operation) and reading image information while transporting a sheet of document by the ADF 10 (swimming operation).

[0021] The scanner unit 20 includes a document glass on which the document is placed, and a reading unit 210 that reads image information of the document placed on the document glass while moving below the document glass in the sub-scanning direction (left-right direction in the figure). The scanner unit 20 also has a glass 201 as a transparent member. The reading unit 210 can optically scan the document transported by the ADF 10 through the glass 201 to read image information.

[0022] The reading unit 210 includes a sensor substrate 213 on which a CCD image sensor as a light-receiving element is mounted, an illumination unit 211 that irradiates the original with light, and a reduction optical system including a plurality of mirrors 212 that images the reflected light from the original onto the imaging surface of the light-receiving element. Here, a CCD type reading unit 210 is shown, but a CIS type reading unit 210 configured to image the reflected light from the original onto the imaging surface of a CMOS image sensor positioned opposite the original via a 1:1 optical system may also be used. The image information read by the reading unit 210 is transmitted to the control unit 2C via the signal line 151.

[0023] The ADF 10 includes a document tray 121, an output tray 122, an ADF body 10A with a document transport path P1 formed inside, and a reading unit 110 positioned on the document transport path P1. The ADF body 10A has a sheet transport means for transporting sheets, which includes a feed roller 101, a pair of separation rollers 102, transport roller pairs 103, 104, 105, and an output roller pair 106 arranged along the document transport path P1. The document tray 121 is a placement section on which sheets as documents are placed, and the output tray 122 is an output section on which sheets from which image information has been read are ejected. The document tray 121 is located above the output tray 122, and in the viewpoint shown in Figure 1(b) (viewed in the sheet width direction), the document transport path P1 is curved in a U-shape, opening to one side in the horizontal direction.

[0024] The reading unit 110 includes a contact image sensor (hereinafter referred to as CIS112) as a reading unit, a reading frame 119 that holds the CIS112, and a glass 111 (see also Figure 3). The glass 111 is a transparent member facing the document transport path P1 (sheet transport path), and the CIS112 functions as a reading unit that reads image information from the document (sheet) being transported along the document transport path P1 via the transparent member.

[0025] The reading frame 119 and the glass 111 form a roughly rectangular parallelepiped space that houses the CIS 112. The CIS 112 includes a sensor substrate 112c on which a CMOS image sensor as a light-receiving element is mounted, an illumination unit 112a that irradiates light onto the document, and a lens 112b that constitutes a 1:1 optical system that focuses reflected light from the document onto the imaging plane of the light-receiving element (see also Figure 3). Here, a CIS-type reading unit 110 is shown, but a CCD-type image sensor unit may also be used as the reading unit 110. The image information read by the reading unit 110 is transmitted to the control unit 2C via the wire 150. The wiring path of the wire 150 will be described in detail later.

[0026] The document transport operation by the ADF10 will be explained using Figure 1(b). When the user sets a stack of documents in the document tray 121 and instructs the start of the scanning operation via an unshown control unit, the documents are fed out of the document tray 121 one by one by the feed roller 101, starting from the top document. The fed documents are transported one by one separated by the separation roller pair 102 and transported along the document transport path P1, passing them sequentially through the transport roller pairs 103, 104, and 105. As the documents pass through the glass 201 of the scanner unit 20, the image information of the first side of the document is read by the reading unit 210. Similarly, as the documents pass through the glass 111, the image information of the second side opposite to the first side of the document is read by the CIS 112 of the reading unit 110. The documents whose image information has been read are discharged to the outside of the ADF main body 10A by the discharge roller pair 106 and stacked on the discharge tray 122.

[0027] In the following description and drawings, the vertical direction when the image forming apparatus 1 is installed on a horizontal plane is defined as the "Z direction". The sheet width direction perpendicular to the document transport direction of the document transported along the document transport path P1 is defined as the "X direction". The X direction is the main scanning direction during image reading, and is preferably perpendicular to the Z direction (horizontal direction). The horizontal direction when viewed in the X direction is defined as the "Y direction". The X, Y, and Z directions are directions that intersect each other, and are preferably perpendicular to each other.

[0028] As shown in Figure 1(b), the ADF 10 includes an upper cover 147 as a cover unit that constitutes the upper surface of the ADF body 10A. The upper cover 147 is rotatably supported by the frame of the ADF body 10A via a support portion 147a and rotates about an axis (first pivot axis) extending in the X direction. The upper cover 147 is provided with a transport guide 148 as an opposing guide (upper guide surface) that forms a document transport path P1 between the guide surface (lower guide surface) of the rotating guide 141 supported by the ADF body 10A. As shown in Figure 1(b), when the upper cover 147 is closed, a part of the rotating guide 141 is covered by the upper cover 147. However, when the upper cover 147 is closed, the entire rotating guide 141 may be covered by the upper cover 147. Furthermore, the upper cover 147 is provided with one of the feed rollers 101, the separation roller pair 102, and the transport roller pair 103 (the upper one in the figure). Therefore, when the upper cover 147 is rotated upward from the closed position shown in Figure 1(b), a part of the document transport path P1 is opened, exposing the rotation guide 141 to the outside of the ADF 10, and the rotation guide 141 can be rotated as described later.

[0029] [Regarding glass cleaning] Incidentally, while the document scanner 2 repeatedly performs a skimming operation, foreign matter such as dust from paper or dirt such as glue and ink that was attached to the original document may adhere to the glass 201,111. If the skimming operation is performed with foreign matter attached to the reading range of the reading units 210,110 on the glass 201,111, streaky images that do not exist in the original document will be read at the positions corresponding to the foreign matter. This is a phenomenon (hereinafter referred to as image streaks) that occurs because the light path during reading by the reading units 210,110 is blocked by the foreign matter attached to the glass 201,111, creating a shadow.

[0030] To eliminate image streaks, it is effective to periodically clean the glass 201 and 111 to remove the foreign matter causing the problem. For the reading unit 210 of the scanner unit 20, the glass 201 of the reading unit 210 is exposed by rotating the ADF 10 upward from the scanner unit 20, allowing cleaning from above. On the other hand, the reading unit 110 of the ADF 10 is located inside the ADF body 10A. As shown in Figure 1(b), in this embodiment, the reading unit 110 is located below the rotation guide 141 and in the area inside the U-shaped curved document transport path P1. Therefore, a configuration to expose the glass 111 (means that allow access to the glass 111) is necessary.

[0031] Here, as a method for exposing the glass 111 of the reading unit 110, it is conceivable to support the reading unit 110 on a rotating guide 141, so that the reading unit 110 rotates integrally with the rotating guide 141. However, in such a configuration, since the reading unit 110 rotates integrally with the rotating guide 141, when the rotating guide 141 strikes another component, an impact is generated corresponding to the total weight of the rotatable unit including the reading unit 110 and the rotating guide 141. The reading unit 110 is a precision device in which electronic circuits including a light-receiving element, and optical elements constituting an illumination unit and a 1:1 or 1:1 optical system or a reduction optical system are arranged inside. Therefore, if a large impact is applied to the reading unit 110 when the rotating guide 141 is rotated to expose the glass 111, there is a possibility that the internal components may be damaged or displaced.

[0032] Therefore, as will be explained below, in this embodiment, a rotating guide 141 is provided as a rotatable transport guide, and the reading unit 110 is configured to rotate independently of the rotating guide 141 around a rotation axis different from the rotation axis of the rotating guide 141. By rotating the rotating guide 141 and the reading unit 110, the glass 111, which is the surface of the reading unit 110 that faces the sheet (the object to be read), is exposed. This reduces the impact that the reading unit 110 receives when it is moved to clean the glass 111 or to clear jams. In addition, by configuring the reading unit 110 to rotate independently of the rotating guide 141, the stress on the wires connecting the reading unit 110 and the control unit 2C can also be reduced.

[0033] The following describes the specific configuration of the reading unit 110 and its surroundings, using examples. [Examples]

[0034] First, Example 1 will be described using Figures 2 to 7. Figure 2 is a side view showing some of the components of the ADF 10. Here, the components located inside the document transport path P1, the base transport guide 143 and the arm 131 are shown when viewed in the X direction from the front side of the image forming apparatus 1. Figure 3 is a cross-sectional view of the reading unit 110 cut by a plane perpendicular to the X direction.

[0035] As shown in Figures 2 and 3, a glass 111 is attached to the bottom of the reading unit 110 that encloses the CIS 112 (the opening of the reading frame 119, which has a roughly U-shaped cross-section). Furthermore, gap sheets 115 are attached to both ends of the glass 111 in the X direction (the longitudinal direction of the CIS 112, the main scanning direction).

[0036] Figure 4 shows the IV-IV cross-section in Figure 2. The IV-IV cross-section is a cross-section obtained by cutting the reading unit 110 with a plane perpendicular to the sheet transport direction D1 at the scanning position of the reading unit 110 (a plane extending in the X direction and the sheet thickness direction D2 at the scanning position). As shown in Figures 2 and 4, each of the two gap sheets 115 attached to both ends of the glass 111 in the X direction abuts against the shading plate 144, which is an opposing member facing the glass 111. As a result, in the region between the gap sheets 115 in the X direction (document passage region), a gap equivalent to the thickness of the gap sheet 115 is guaranteed between the glass 111 and the shading plate 144, as shown in Figure 3. In other words, the gap sheet 115 functions as a gap-forming member that abuts against the opposing member facing the glass 111 and forms a gap between the glass 111 and the opposing member. As long as the gap width is guaranteed (specified), the gap sheet 115 is not the only option; for example, a projection that protrudes from the glass 111 may be formed integrally with the reading frame 119.

[0037] The shading plate 144 is attached to the base transport guide 143, which is a transport guide facing the reading unit 110, and the base transport guide 143 is attached to the frame of the ADF 10. In other words, the shading plate 144 and the base transport guide 143 are components fixed to the frame of the ADF 10.

[0038] Furthermore, a pressurizing section 114 is provided to pressurize the reading unit 110 so that it can stably remain stationary at the point where it abuts against the gap sheet 115 (Figure 4). The pressurizing section 114 is located on the upper part of the reading unit 110 (opposite side from the glass 111). The pressurizing section 114 includes a resin cover 114a as a contacting part that abuts against a pressurizing surface 141a (Figure 2) provided on the bottom surface of the rotation guide 141, and a compression spring 114b as an elastic member interposed between the resin cover 114a and the reading frame 119.

[0039] The rotating guide 141 has a shaft portion 141c that is rotatably supported by the frame of the ADF 10, and is rotatable about a pivot axis A1 (second pivot axis). In this embodiment, the pivot axis A1 is assumed to be provided at the upstream end (one end in the Y direction) of the rotating guide 141 in the conveying direction of the sheet being conveyed from the feed roller 101 toward the separation roller pair 102, but the pivot axis A1 may be provided at other positions. Furthermore, the support portion for rotatably supporting the rotating guide 141 is not limited to the shaft portion 141c, and a hole (bearing) may be provided in the rotating guide 141 to fit the shaft shape provided in the frame of the ADF 10. The rotating guide 141 is rotatable between a position for guiding the lower surface of the document being conveyed along the document conveying path P1 (see Figure 2; hereinafter referred to as the closed position) and a position moved upward from the closed position (see Figure 6; hereinafter referred to as the open position). The closed position is the position where the rotating guide 141 covers the reading unit 110 when viewed from above (third position), and the open position is the position where the rotating guide 141 exposes the reading unit 110 when viewed from above (fourth position). The rotating guide 141 is held in the closed position by the engagement of a fixed portion 141d provided at its tip with a transport guide 142 fixed to the ADF body 10A.

[0040] With the rotating guide 141 in the closed position, the pressing surface 141a of the rotating guide 141 contacts the resin cover 114a of the pressing section 114. Then, due to the elasticity of the compression spring 114b generated by the pressing of the resin cover 114a, the reading unit 110 is pressed toward the shading plate 144. This stabilizes the position of the reading unit 110 in the sheet thickness direction D2, contributing to high-precision reading of image information.

[0041] The reading unit 110 has a shaft portion 113 that is rotatably supported by the frame of the ADF 10, and is rotatable around a rotation axis A2 (third rotation axis) that is different from the rotation axis A1 of the rotation guide 141. Note that the support portion for rotatably supporting the reading unit 110 is not limited to the shaft portion 113; a hole (bearing) may be provided in the reading frame 119 and the shaft shape provided in the frame of the ADF 10 may be fitted into it. The reading unit 110 is rotatable between a position in which image information can be read from a document being transported along the document transport path P1 (see Figure 2; hereinafter referred to as the reading position) and a position in which the glass 111 is exposed (see Figure 6; hereinafter referred to as the maintenance position). The reading position is the position of the reading unit 110 (first position) where the transparent glass 111 faces the document transport path P1, and the maintenance position is the position of the reading unit 110 (second position) where the glass 111 is exposed when viewed from outside the ADF 10.

[0042] With the reading unit 110 in the reading position, the glass 111 faces the shading plate 144 or the base transport guide 143 across the document transport path P1, and when viewed from above in the vertical direction, the glass 111 is hidden by the reading frame 119. The maintenance position is the position of the reading unit 110 in which at least a part of the glass 111 (preferably the area encompassing the reading range of the CIS 110 or the entire glass 111) is exposed when the ADF 10 is viewed from a predetermined direction (for example, above in the vertical direction).

[0043] The shaft portion 113 is provided, for example, protruding outward in the X direction from both ends of the reading frame 119 in the X direction (longitudinal direction), and is held by a holding portion B1 provided on the frame of the ADF 10. Therefore, the pivot axis A1 of the rotation guide 141 and the pivot axis of the reading unit 110 are substantially parallel to each other and both extend substantially in the X direction. The holding portion B1 is a concave shape (opening) that rotatably holds the shaft portion 113, and in this embodiment, the holding portion B1 is an elongated oval hole (groove) that extends elongated in the sheet thickness direction D2. The holding portion B1 as an oval hole is provided, for example, on a side plate (a plate-shaped member that extends in the Y and Z directions outside the document passage area in the X direction) that constitutes the frame of the ADF 10.

[0044] The pivot axis A1 of the pivot guide 141 is located at one end of the pivot guide 141 in the Y direction (right side in Figure 2), whereas the shaft portion 113 of this embodiment is located at the other end of the reading unit 110 in the Y direction (left side in Figure 2) and the upper end in the Z direction. Therefore, the reading unit 110 rotates counterclockwise in the figure (first rotation direction) from the reading position to the maintenance position, while the pivot guide 141 rotates clockwise in the figure (second rotation direction) from the closed position to the open position. Configuring the pivot guide 141 and the reading unit 110 to rotate in opposite directions has the advantage of making it easier to secure the rotation range of the reading unit 110 without being affected by the pivot guide 141 in the open position. Note that the rotation direction of the pivot guide 141 when open is also opposite to the rotation direction of the upper cover 147 when open.

[0045] Next, the arm 131 will be described. The arm 131 is rotatably supported by the frame of the ADF 10 and rotates in conjunction with the rotation of the rotation guide 141 from the closed position to the open position, thereby moving the reading unit 110 from the reading position to the maintenance position. In other words, the arm 131 is an example of an interlocking mechanism that moves the reading unit 110 in conjunction with the rotation of the rotation guide 141. In this embodiment, the arm 131 rotates around a rotation axis A1 common to the rotation guide 141 and is a component that can rotate independently of the rotation guide 141.

[0046] As shown in Figures 5(a, b), the rotating guide 141 is provided with an arm contact portion 141b, and the arm 131 is provided with a contacted portion 131e that contacts the arm contact portion 141b. When the rotating guide 141 is in the closed position and the reading unit 110 is in the reading position, the arm contact portion 141b is spaced apart from the contacted portion 131e. In addition, the tip side of the arm 131 is provided with arc profiles 131a, 131b, and 131c as contact portions for pressing the reading unit 110. Details of the arc profiles 131a, 131b, and 131c will be described later.

[0047] In this embodiment, the arm 131 moves in conjunction with the rotation guide 141 only within a range, and the rotation range of the arm 131 is narrower than the rotation range of the rotation guide 141. Specifically, in the closed position of the rotation guide 141, the arm contact portion 141b of the rotation guide 141 does not contact the arm 131, and the arm contact portion 141b contacts the arm 131 during the rotation of the rotation guide 141 to the open position (Figure 5(a, b)). As a result, the rotation trajectory of the arm 131 is smaller compared to when the arm 131 rotates integrally with the rotation guide 141, and less space is required to position the arm 131.

[0048] This section explains the operation of moving the reading unit 110 from the reading position to the maintenance position during maintenance work. The operator (user or maintenance staff) should, in advance, rotate the upper cover 147 upward from the closed position shown in Figure 1(b) to open it.

[0049] First, in the state shown in Figure 2, in order to secure space for the reading unit 110 to rotate, the operator places their hand on the rotation guide 141 and rotates it clockwise around the rotation axis A1 in the figure. When this is done, as shown in Figure 5(a), the rotation guide 141 moves upward away from the reading unit 110, and the arm contact portion 141b moves closer to the contact portion 131e of the arm 131.

[0050] As the rotation guide 141 is further rotated, as shown in Figure 5(b), the arm contact portion 141b comes into contact with the contacted portion 131e of the arm 131, causing the arm 131 to rotate clockwise around the rotation axis A1. As the arm 131 rotates, the arc profiles 131a and 131c provided on the tip side of the arm 131 come into contact with and press against the reading unit 110, causing the reading unit 110 to rotate counterclockwise around the shaft portion 113. As a result, the reading unit 110 moves from the reading position shown in Figure 2 to the maintenance position shown in Figure 6.

[0051] The operator can easily perform tasks such as cleaning the glass 111 on the reading unit 110 after it has been moved to the maintenance position. The rotating guide 141 can be configured to hold the reading unit 110 in the maintenance position via the arm 131, for example, by remaining in the open position due to its own weight. As will be described in more detail later, when the reading unit 110 reaches the maintenance position, the pressurized part 114 of the reading unit 110 comes into contact with the abutment surface 142a (Figure 6) of the transport guide 142 fixed to the frame of the ADF body 10A.

[0052] After cleaning the glass 111 and completing other tasks, in the state shown in Figure 6, the operator rotates the rotating guide 141 counterclockwise from the open position to the closed position. The arm 131 then rotates counterclockwise in accordance with the rotation of the rotating guide 141. The reading unit 110, supported by the arm 131, rotates clockwise from the maintenance position to the reading position. When the rotating guide 141 reaches the closed position, the reading unit 110 returns to the state shown in Figure 2, where it is held in the reading position. In other words, in this embodiment, the reading unit 110 moves from the reading position to the maintenance position in conjunction with the opening of the rotating guide 141, and moves from the maintenance position to the reading position in conjunction with the closing of the rotating guide 141.

[0053] In this way, by configuring the reading unit 110 to be rotatable around a pivot axis separate from the rotation guide 141, the impact received by the reading unit 110 when it is moved for cleaning or jamming the glass 111 can be reduced.

[0054] Furthermore, in this embodiment, the holding portion B1 on the mating side (the frame side of the ADF 10) of the shaft portion 113 of the reading unit 110 is configured as an elongated oval hole extending in the sheet thickness direction D2. In order to allow the reading unit 110 to rotate independently of the rotation guide 141, the holding portion B1 may be configured as a cylindrical hole corresponding to the shaft portion 113. However, in this embodiment, by configuring the holding portion B1 as an elongated oval hole, movement in the sheet thickness direction D2 is permitted in addition to the rotation of the reading unit 110. This restricts the positional deviation of the reading unit 110 in the sheet transport direction D1, while absorbing positional variations of the reading unit 110 due to component tolerances of the ADF 10, etc., by the movement of the shaft portion 113 relative to the holding portion B1. By absorbing the positional variations of the reading unit 110, the glass 111 can be positioned more stably with respect to the shading plate 144 with the gap sheet 115 in between.

[0055] Furthermore, as shown by the arrows in Figure 6, when the reading unit 110 is rotated to the maintenance position, the reading unit 110 can be lifted upward by the length of the holding part B1, thereby improving the workability for maintenance and other tasks. In this case, if the abutment surface 142a of the transport guide 142 is configured as an inclined surface having a slope along the holding part B1, it also functions as a guide when lifting the reading unit 110. In this embodiment, the longitudinal direction of the elongated hole which is the holding part B1 is configured to substantially coincide with the sheet thickness direction D2 at the reading position of the reading unit 110. However, the holding part B1 may be an elongated hole that extends in a direction different from the sheet thickness direction D2 in a direction that intersects the sheet transport direction D1 when viewed in the X direction, as long as it can restrict the positional displacement of the reading unit 110 in the sheet transport direction D1 at the reading position.

[0056] [Wiring to the reading unit] Next, the wiring route of the reading unit 110 in this embodiment and its advantages will be described. As mentioned above, the reading unit 110 is electrically connected to the control unit 2C (Figure 1(b)) of the document reading device 2 via the electric wire 150. The electric wire 150 is a signal line that transmits the image information read by the reading unit 110 to the control unit 2C, and is also a power line that supplies power to the reading unit 110. In this embodiment, an FFC (Flexible Flat Cable) is used as the electric wire 150.

[0057] As shown in Figures 2 and 3, the electric wire 150 is connected to the sensor board 112c inside the reading unit 110 and is led out to the outside of the reading unit 110 through an opening (outlet 146) provided in the reading frame 119. Outside the reading unit 110, the electric wire 150 is guided by a guide member attached to the frame of the ADF 10 and wired inside the ADF body 10A, and connected to the control unit 2C of the scanner unit 20. Therefore, the electric wire 150 includes an internal unit portion 150a held inside the reading unit 110, a body-side portion 150b held in the frame of the ADF body 10A, and an intermediate portion 150c connecting the internal unit portion 150a and the body-side portion 150b. The intermediate portion 150c is the portion between the outlet 146 of the reading unit 110 and the inlet 149 on the ADF body side (an opening to receive the electric wire 150 or a guide member to hold the electric wire 150). Furthermore, in order to allow the intermediate portion 150c to bend easily, the electric wire 150 (FFC) is arranged such that the width direction of the electric wire 150 in the intermediate portion 150c is substantially parallel to the X direction, which is the main scanning direction of the reading unit 110.

[0058] When the reading unit 110, which is a movable member that can move relative to the frame of the ADF main body 10A, moves, the bending of the electric wire 150 allows the movement of the reading unit 110. That is, when the reading unit 110 is rotated from the reading position shown in Figure 17(a) to the maintenance position shown in Figure 17(b), the bending of mainly the middle portion 150c of the electric wire 150 follows the change in posture of the reading unit 110, allowing the rotation of the reading unit 110. Also, as shown in Figure 17(c), when the reading unit 110 in the maintenance position is lifted upward along the holding part B1, the middle portion 150c of the electric wire 150 stretches (the bending due to excess length is eliminated), allowing the upward movement of the reading unit 110.

[0059] Here, we will explain that in this embodiment, by configuring the reading unit 110 to be rotatable independently of the rotation guide 141, the stress on the electric wire 150 when the reading unit 110 is rotated can be reduced.

[0060] As shown in Figure 3, the electric wire 150 is drawn out from the inside to the outside of the reading unit 110, passing near the pivot axis A2 of the reading unit 110. When viewed in the X direction, the distance from the pivot axis A2 (third pivot axis) of the reading unit 110 to the outlet 146 through which the electric wire 150 is drawn out of the reading unit 110 is shorter than the distance from the pivot axis A1 (second pivot axis) of the rotation guide 141 to the outlet 146. Therefore, the amount of movement of the outlet 146 when the reading unit 110 is rotated is smaller compared to when the reading unit 110 is mounted on the rotation guide 141. Furthermore, the vicinity of the pivot axis A2 is preferably such that the electric wire 150 passes through a position that overlaps with the shaft portion 113 when viewed in the X direction. Furthermore, it is preferable to arrange the four corners of the reading frame 119, which is roughly rectangular when viewed in the X direction, such that the corner closest to the outlet 146 for drawing out the electric wire 150 and the corner closest to the shaft portion 113 are the same.

[0061] In this way, when the electric wire 150 is routed near the pivot axis A2 of the reading unit 110, the electric wire 150 bends mainly near the pivot axis A2 when the reading unit 110 is rotated around the pivot axis A2 (see Figure 17(b)). In other words, the electric wire 150 bends so that the internal portion 150a of the electric wire 150 rotates with the vicinity of the pivot axis A2 as the pivot point. Therefore, the variation in distance from the outlet 146 of the electric wire 150 on the reading unit 110 side to the inlet 149 of the electric wire 150 on the ADF body 10A side is small. If the variation in distance from the outlet 150 of the electric wire 150 on the reading unit 110 side to the inlet 150 of the electric wire 150 on the ADF body 10A side is large, there is a risk that the electric wire 150 may break or become detached due to tension. Therefore, it is conceivable to increase the excess length of the intermediate section 150c to account for fluctuations, but increasing the excess length of the intermediate section 150c would lead to increased costs and larger equipment. In contrast, in this embodiment, the amount of fluctuation in the distance from the outlet of the wire 150 on the reading unit 110 side to the inlet of the wire 150 on the ADF main body 10A side is small, so even if the excess length of the intermediate section 150c is set short, disconnections and other problems are less likely to occur, thus preventing increased costs and larger equipment.

[0062] Incidentally, if the reading unit 110 is configured to rotate integrally with the rotating guide 141, it becomes difficult to route the electric wire 150 via the vicinity of the rotating axis A2. This is due to the following reasons. First, a conveying guide that guides a sheet, such as the rotating guide 141, is a relatively large component that extends along the sheet conveying path. Therefore, when attempting to rotate such a large component as a conveying guide, it is natural to position the rotating axis of the conveying guide near the upstream or downstream end of the conveying guide in the direction of conveying the sheet being guided. On the other hand, since the reading unit is positioned away from the guide surface of the conveying guide (below the rotating guide 141 in the case of the reading unit 110) so as not to obstruct the conveying of the sheet, it becomes difficult to position the outlet of the electric wire from the reading unit near the rotating axis of the conveying guide. Furthermore, conveying rollers that convey the sheet are often positioned near the conveying guide, and if the reading unit is positioned to avoid interference with the conveying rollers, it becomes even more difficult to position the outlet of the electric wire from the reading unit near the rotating axis of the conveying guide. The further the wire exit from the reading unit is from the pivot axis of the transport guide, the greater the variation in distance from the wire exit on the reading unit side to the wire inlet on the ADF body side when the transport guide is rotated. As a result, there is a risk of wire 150 breaking.

[0063] In contrast, this embodiment employs a configuration in which the reading unit 110 rotates independently of the rotation guide 141, allowing the electric wire 150 to be routed near the rotation axis A2 of the reading unit 110. Furthermore, the rotation axis A2 of the reading unit 110 can be positioned below the guide surface of the rotation guide 141. As a result, as described above, the likelihood of the electric wire 150 breaking can be reduced.

[0064] [Arm details] Next, a configuration that allows the reading unit 110 to rotate within a wide range of motion while improving operability when moving the reading unit 110 will be explained using Figures 7 and 8.

[0065] In the reading unit 110, the glass 111 is positioned so that it faces downward in the Z direction when in the reading position, and the glass 111 is exposed when viewed from above in the Z direction when in the maintenance position. In other words, in this embodiment, when the reading unit is in the first position, the transparent member faces downward in the vertical direction, and when the reading unit is in the second position, the transparent member faces upward in the vertical direction.

[0066] If the tilt of the glass 111 relative to the horizontal at the reading position is too great, the curvature of the document transport path P1 becomes too sharp, making it difficult to transport thick paper and the like. Therefore, the tilt of the glass 111 is set to, for example, 45 degrees or less, preferably 30 degrees or less. For this reason, the reading unit 110 is configured to be rotatable between the reading position and the maintenance position within a wide range of rotation, for example, 60 degrees or more, preferably 75 degrees or more, and more preferably 90 degrees or more.

[0067] When rotating the reading unit 110 over such a wide range of motion, in a configuration where an operator directly grips and rotates the reading unit 110, there is a risk of the operator's hand getting caught between the rotated reading unit 110 and other parts of the ADF 10, and there was room for improvement in operability.

[0068] As described above, in this embodiment, the tip of the arm 131, which is linked to the rotation of the rotation guide 141, contacts the reading unit 110 from below, causing the reading unit 110 to rotate in conjunction with the rotation guide 141 (see Figures 5(b) and 6). At this time, the arm 131 rotates in the opposite direction to the reading unit 110, changing its contact position with the reading unit 110, thereby rotating the reading unit 110 from the reading position to the maintenance position. This allows the reading unit 110 to rotate over a wide range of motion while improving operability. Furthermore, since it is possible to move the reading unit 110 from the reading position to the maintenance position with the smallest possible operating force, the operating load can be reduced. A detailed explanation follows below.

[0069] Figure 7 shows the positional relationship between the reading unit 110, the pivot axis A1 of the arm 131, and the pivot axis A2 of the reading unit 110 when the arm 131 first contacts the reading unit 110. In order to rotate the reading unit 110 counterclockwise by contacting it from below with the arm 131, it is efficient to contact the first contact surface 110a, which is the lower surface of the reading unit 110 at the reading position (the surface on which the glass 111 is placed). Next, to consider at what position on the first contact surface 110a the arm 131 should contact, we consider three points a, b, and c. The dashed lines passing through each point are the rotational trajectories around the pivot axis A1 at that point, and the arrows indicate the tangential direction (the direction of the load when the arm 131 presses against the reading unit 110 at each point).

[0070] When the arm 131 contacts the reading unit 110 at point a, the direction of the load is almost directly toward the rotation axis A2 of the reading unit 110, making it inefficient to rotate the reading unit 110. When the arm 131 contacts the reading unit 110 at point c, a moment in the clockwise direction in the figure, which is opposite to the direction in which we want to rotate the reading unit 110, acts on the reading unit 110. On the other hand, when the arm 131 contacts the reading unit 110 at a position on the first contact surface 110a that is to the right of the rotation axis A2 in the figure, as in point b, the reading unit 110 rotates even if the load applied by the arm 131 to the reading unit 110 is relatively small.

[0071] Figure 8 shows the maximum angle at which the reading unit 110 can be rotated by pressing the first contact surface 110a from below. If the arm 131 were in contact with the first contact surface 110a at point d in the figure, when the reading unit 110 rotates to a position where the first contact surface 110a is vertical, the arm 131 can no longer press the reading unit 110 any further at point d. In order to rotate the reading unit 110 further, the arm 131 is configured to press the reading unit 110 by contacting it at a second contact surface 110b, which is different from the first contact surface 110a, as shown at point e.

[0072] In this embodiment, based on the above, the arm 131 is provided with two contact portions (131a, 131c), and the two contact portions sequentially contact and press against the first contact surface 110a and the second contact surface 110b of the reading unit 110.

[0073] The configuration will be described in detail below. As shown in Figure 5(b), the tip of the arm 131 in this embodiment is provided with three arc profiles 131a, 131b, and 131c. These are referred to as the first arc profile 131a, the second arc profile 131b, and the third arc profile 131c, extending radially outward from the rotation axis A1 of the arm 131. The first arc profile 131a and the third arc profile 131c are arc-shaped curved surfaces that are convex toward the downstream side in the rotation direction of the arm 131 when pressing the reading unit 110 (clockwise direction in the figure). The first arc profile 131a is the first convex portion that presses against the first contact surface 110a (first surface) of the reading unit 110. The third arc profile 131c is a second convex portion that presses against the second contact surface 110b (second surface) of the reading unit 110. The second arc profile 131b is an arc-shaped curved surface recessed between the first arc profile 131a and the third arc profile 131c, forming a space that receives the corner 110c between the first contact surface 110a and the second contact surface 110b. In this embodiment, the first contact surface 110a and the second contact surface 110b are two adjacent surfaces (perpendicularly intersecting surfaces) of the reading unit 110, which are substantially rectangular when viewed in the X direction. However, the first and second surfaces may be surfaces extending in directions that intersect each other at angles other than perpendicular.

[0074] In this embodiment, the first contact surface 110a of the reading unit 110 is the surface of the gap sheet 115 (gap-forming member) attached to the glass 111. By preventing the arm 131 from directly contacting the glass 111, the possibility of damage to the glass 111 is reduced. As shown in Figure 4, the contact position of the arm 131 with respect to the gap sheet 115 is offset in the X direction from the abutment area of ​​the shading plate 144 with respect to the gap sheet 115. Therefore, even if the surface of the first contact surface 110a of the gap sheet 115 becomes rough due to repeated contact with the arm 131, the accuracy of the gap width formed between the glass 111 and the shading plate 144 does not decrease.

[0075] As shown in Figure 5(b), when the arm 131 rotates in conjunction with the rotation of the rotation guide 141, the first arc profile 131a first contacts the first contact surface 110a of the reading unit 110, causing the reading unit 110 to start rotating from the reading position. At this time, the third arc profile 131c is not in contact with the second contact surface 110b of the reading unit 110.

[0076] As the arm 131 rotates further and the reading unit 110 reaches a predetermined angle, the third arc profile 131c comes into contact with the second contact surface 110b, while the first arc profile 131a moves away from the first contact surface 110a. Then, as the third arc profile 131c presses against the second contact surface 110b, the reading unit 110 is rotated to the maintenance position, as shown in Figure 6.

[0077] When the reading unit 110 reaches the maintenance position, as shown in Figure 6, the pressurizing section 114 of the reading unit 110 abuts against the abutting surface 142a of the transport guide 142 fixed to the frame of the ADF main body 10A. At this time, the elasticity of the elastic member (compression spring 114b) provided in the pressurizing section 114 mitigates the impact of the reading unit 110 hitting the transport guide 142. In other words, the pressurizing section 114 not only positions the reading unit 110 during image reading, but also acts as a buffer when the reading unit 110 is moved to the maintenance position.

[0078] In this way, by configuring the contact position between the arm 131 and the reading unit 110 to switch according to the rotation angle of the reading unit 110, the reading unit 110 can be rotated over a wide range of motion while reducing the operating load. Furthermore, because a concave arc profile 131c is provided between the two protrusions of the arm 131 that contact the first contact surface 110a and the second contact surface 110b of the reading unit 110, the arm 131 and the reading unit 110 do not become locked by the two protrusions. That is, the corners 110c of the first contact surface 110a and the second contact surface 110b are accommodated in the space inside the arc profile 131c, allowing for a smooth transition from the contact state between the first arc profile 131a and the first contact surface 110a to the contact state between the third arc profile 131c and the second contact surface 110b.

[0079] Furthermore, in this embodiment, the three arc profiles 131a, 131b, and 131c are smoothly connected (the tangential direction does not change discontinuously), which allows for smooth rotation when the contact position of the reading unit 110 switches between each profile.

[0080] In this embodiment, the two convex portions and the concave portion between them are described as being composed of circular arcs, but they may be composed of curves other than circular arcs.

[0081] (Variation 1) In Embodiment 1, a configuration was described in which the reading unit 110 rotates in conjunction with the opening and closing of the rotating guide 141 via an arm 131 that is linked to the rotating guide 141. However, the configuration is not limited to this, and as shown in Figure 9, the reading unit 110 may be rotated by the operator directly by hand without providing the arm 131. In this case, in order to move the reading unit 110 to the maintenance position, the operator first grasps the rotating guide 141 and rotates it from the closed position to the open position, and then grasps the reading unit 110 and rotates it from the reading position to the maintenance position.

[0082] (Modification 2) Furthermore, as another configuration in which the reading unit 110 rotates in conjunction with the opening and closing of the rotating guide 141, the arm 131 may be formed integrally with the rotating guide 141, so that a part of the rotating guide 141 contacts the reading unit 110. In Embodiment 1, the arm 131 is rotatable relative to the rotating guide 141, and the rotation range of the arm 131 is narrower than the rotation range of the rotating guide 141. As a result, as described above, the device can be made smaller compared to this modified example.

[0083] (Variation 3) In Embodiment 1, the arm 131 was described as being positioned on one side in the X direction of the reading unit 110 and the rotating guide 141, but the arm 131 may be positioned on both sides in the X direction. In that case, torsional loads will be less likely to be applied to the reading unit 110 and the rotating guide 141. [Examples]

[0084] Embodiment 2 will be described using Figures 10 to 12. This embodiment differs from Embodiment 1 in that the reading unit 110 rotates when the operator grasps the operating part of the arm 131 and operates the arm 131 with the rotation guide 141 already moved to the open position. Hereafter, elements with the same reference numerals as in Embodiment 1 have substantially the same configuration and operation as those described in Embodiment 1, and the elements that differ from Embodiment 1 will be mainly described.

[0085] As shown in Figure 10, the arm 131 of this embodiment has an arm operating section 131d as an operating section (lever, handle). The arm operating section 131d is positioned so as to be easily accessible to the operator when the upper cover 147 is open, for example, on the front side of the image forming apparatus 1 and protruding above the guide surface of the rotation guide 141. The arm operating section 131d is described as rotating integrally with the other parts of the arm 131, but it may also be connected so as to be rotatable relative to the other parts of the arm 131 only within a predetermined range of rotation.

[0086] When moving the reading unit 110 from the reading position to the maintenance position during maintenance work, the operator first opens the upper cover 147 and then moves the rotation guide 141 to the open position. In this state, the operator places their hand on the arm operating section 131d and rotates the arm 131 clockwise in the diagram.

[0087] As shown in Figures 11 and 12, the arc profiles 131a and 131c provided on the tip side of the arm 131 come into contact with and press against the reading unit 110, causing the reading unit 110 to rotate counterclockwise around the shaft portion 113. This moves the reading unit 110 from the reading position shown in Figure 10 to the maintenance position shown in Figure 12. By configuring the reading unit 110 to rotate independently of the rotation guide 141 in this way, the impact received by the reading unit 110 when it is moved for cleaning or jamming the glass 111 can be reduced.

[0088] Furthermore, in the process of rotating the arm 131, similar to Embodiment 1, the two arc profiles 131a and 131c provided on the arm 131 come into contact with the first contact surface 110a and the second contact surface 110b of the reading unit 110 in sequence. At this time, if the operator wants to move the reading unit 110 to the maintenance position, they only need to operate the arm operating section 131d, and there is little possibility of their hand getting caught between the reading unit 110 and the ADF body 10. Thus, the reading unit 110 can be rotated over a wide range of motion while improving operability.

[0089] In this embodiment as well, by configuring the reading unit 110 to rotate independently of the rotation guide 141, the risk of wire breakage of the electric wire 150 when the reading unit 110 is rotated can be reduced. [Examples]

[0090] Embodiment 3 will be described using Figures 13 and 14. In this embodiment, the position of the pivot axis of the reading unit 110 and the rotation direction of the reading unit 110 differ from those of Embodiment 1. Hereafter, elements with the same reference numerals as in Embodiment 1 have substantially the same configuration and operation as those described in Embodiment 1, and the elements that differ from those in Embodiment 1 will be mainly described.

[0091] As shown in Figure 13, the reading unit 110 has a shaft portion 113 that is rotatably supported by the frame of the ADF 10, and is rotatable about a pivot axis A3 (second pivot axis) that is different from the pivot axis A1 of the pivot guide 141 which serves as a transport guide. In this embodiment, the pivot axis A3 of the reading unit 110 is provided at the end on one side in the Y direction (negative side in the Y direction) and the upper end in the Z direction of the reading unit 110. In other words, in this embodiment, the first pivot axis is provided at the upstream end of the transport guide in the sheet transport direction (left side in the figure) of the sheet guided by the transport guide. The second pivot axis is provided at the upstream end of the reading unit in the sheet transport direction of the sheet guided by the transport guide.

[0092] Therefore, the rotating guide 141 rotates clockwise around the pivot axis A1 from the closed position to the open position, and the reading unit 110 rotates clockwise around the pivot axis A3 from the reading position to the maintenance position. In this way, even if the rotation direction of the rotating guide 141 and the reading unit 110 is the same when the glass 111 as a transparent member is exposed, the same effects as in Examples 1 and 2 can be obtained. Whether the rotation direction of the rotating guide 141 and the reading unit 110 is the same or opposite is selected according to the specific configuration of the ADF 10, such as the positional relationship with the members arranged around them.

[0093] Incidentally, in this embodiment, since the position of the pivot axis A3 of the reading unit 110 is different from that of embodiments 1 and 2, it is preferable to change the wiring route of the electric wire 150 connected to the reading unit 110 from that of embodiments 1 and 2. As shown in Figure 13, the electric wire 150 is drawn out from the inside to the outside of the reading unit 110 via the vicinity of the pivot axis A3 of the reading unit 110. In this case, unlike embodiment 1, the electric wire 150 is drawn out on the negative side in the Y direction (downstream side of the sheet transport direction D1 at the reading position) and is guided and wired by a guide member 152 provided on the frame of the ADF body 10.

[0094] The distance from the pivot axis A3 of the reading unit 110 to the exit point for drawing the electric wire 150 from the reading unit 110 is at least shorter than the distance from the pivot axis A1 of the rotating guide 141 to the exit point. Furthermore, the vicinity of the pivot axis A3 is preferably such that the electric wire 150 passes through a position that coincides with the shaft portion 113 when viewed in the X direction. In addition, it is preferable that the four corners of the reading frame 119, which is roughly rectangular when viewed in the X direction, be arranged such that the corner closest to the exit point for drawing the electric wire 150 is the same as the corner closest to the shaft portion 113.

[0095] As described above, when the electric wire 150 is routed near the pivot axis A3 of the reading unit 110, the electric wire 150 bends mainly around the pivot axis A3 when the reading unit 110 is rotated around the pivot axis A3 (see Figure 13). Therefore, the variation in distance from the exit of the electric wire 150 on the reading unit 110 side to the inlet 149 of the electric wire 150 on the ADF body 10A side (the opening that receives the electric wire 150 or the guide member that holds the electric wire 150) is small. Consequently, even with the configuration of this embodiment, the possibility of the electric wire 150 breaking can be reduced. [Examples]

[0096] Embodiment 4 will be described with reference to Figure 15. In this embodiment, the position of the pivot axis of the pivot guide 141 and the rotation direction of the pivot guide 141 differ from those of Embodiment 2. Hereafter, elements with the same reference numerals as in Embodiment 2 have substantially the same configuration and function as those described in Embodiment 2, and the elements that differ from those in Embodiment 2 will be mainly described.

[0097] As shown in Figure 15, the rotating guide 141, which serves as a transport guide, is rotatably mounted around a pivot axis A4 (the first pivot axis). The pivot axis A1 is located at the downstream end (left side in the figure, positive Y direction) of the rotating guide 141 in the sheet transport direction of the sheet guided by the rotating guide 141. In other words, in this embodiment, the first pivot axis is located at the downstream end of the transport guide in the sheet transport direction of the sheet guided by the transport guide. The second pivot axis is located at the downstream end of the reading unit in the sheet transport direction of the sheet guided by the transport guide.

[0098] Therefore, the rotating guide 141 rotates counterclockwise around the pivot axis A4 from the closed position to the open position, and the reading unit 110 rotates counterclockwise around the pivot axis A2 from the reading position to the maintenance position. Even with this configuration, the same effects as in Examples 1 and 2 can be obtained.

[0099] (modified version) A modified example will be explained using Figure 16. This embodiment combines the position of the pivot axis A4 of the pivot guide 141 and the rotation direction of the pivot guide 141 in Embodiment 4 with the position of the pivot axis A3 of the reading unit 110 and the rotation direction of the reading unit 110 in Embodiment 3. In other words, in this embodiment, the first pivot axis is provided at the downstream end of the conveyor guide in the sheet conveying direction of the sheet guided by the conveyor guide. The second pivot axis is provided at the upstream end of the reading unit in the sheet conveying direction of the sheet guided by the conveyor guide.

[0100] Therefore, the rotating guide 141 rotates counterclockwise around the pivot axis A4 from the closed position to the open position, and the reading unit 110 rotates clockwise around the pivot axis A3 from the reading position to the maintenance position. Even with this configuration, the same effects as in Examples 1 and 2 can be obtained. [Examples]

[0101] Example 5 will be described with reference to Figures 18 and 19. This example differs from Example 2 in that multiple arm members are in contact with the first and second contact surfaces of the reading unit. Hereinafter, elements with the same reference numerals as in Example 2 have substantially the same configuration and function as those described in Example 2, and the elements that differ from Example 2 will be mainly described.

[0102] The ADF10 in this embodiment includes an arm 132 as a first arm member and an arm 133 as a second arm member. Arms 132 and 133 are rotatably supported by the frame of the ADF body 10A and both rotate around a pivot axis A1. Arms 132 and 133 overlap each other when viewed in the X direction. Furthermore, both arms 132 and 133 can be rotated by operating the arm operating part 131d. Even with this configuration, the same effects as in Embodiment 2 can be obtained.

[0103] When the arm operating section 131d is rotated clockwise from the state shown in Figure 18, the arm 132 rotates first and contacts the first contact surface 110a of the reading unit 110. Then, when the arm 132 has rotated by a predetermined angle, the arm 133 begins to rotate and contacts the second contact surface 110b of the reading unit 110. As a result, the reading unit 110 is rotated to the maintenance position as shown in Figure 19. In this way, by pressing multiple surfaces of the reading unit 110 with the two arms 132 and 133, the reading unit 110 can be rotated over a wide range of motion. Furthermore, by configuring the two arms 132 and 133, which are arranged in a stacked manner, to interlock with a time difference, the space required for the placement of the arms 132 and 133 can be reduced. [Examples]

[0104] Embodiment 6 will be described with reference to Figures 20 and 21. This embodiment differs from Embodiment 2 in that the contact surface on the reading unit side that abuts against the arm member is curved, thereby securing the rotation range of the reading unit. Hereinafter, elements with the same reference numerals as in Embodiment 2 have substantially the same configuration and function as those described in Embodiment 2, and the elements that differ from Embodiment 2 will be mainly described.

[0105] As shown in Figure 20, the reading unit 110 of this embodiment is provided with an arm contact surface 110d separate from the surface on which the glass 111 is placed. The arm contact surface 110d is a substantially arc-shaped curved surface that is convex toward the upstream side in the rotation direction of the arm 131 (clockwise direction in the figure) when viewed in the X direction. On the other hand, the tip of the arm 131 is formed in a substantially straight line along the straight line passing through the rotation axis A1. The arm contact surface 110d is a substantially continuous curved surface at least between the first contact point d1 (Figure 20) and the second contact point d2 (Figure 21). The first contact point d1 is the position where the arm 131 is in contact when the reading unit 110 is in the reading position. The second contact point d2 is the position where the arm 131 is in contact when the reading unit 110 is in the maintenance position.

[0106] When the arm 131 is rotated clockwise in the figure, the arm 131 rotates the reading unit 110 from the reading position to the maintenance position, while continuously changing the contact position with respect to the arm contact surface 110d from the first contact point d1 to the second contact point d2. Therefore, with the configuration of this embodiment, even if the arm 131 has a simple shape, the same effect as in Embodiment 2 can be obtained, and the degree of design freedom can be increased.

[0107] (Other embodiments) The above-described embodiment explains the configuration in which this technology is applied to an image reading device installed on top of the main body of an image forming apparatus. However, this technology is not limited to this configuration and can also be applied to an image reading device independent of the image forming apparatus. [Explanation of symbols]

[0108] 2…Image reading device (document reading device) / 101,102,103,104,105,106…Sheet transport means / 110…Reading unit / 111…Transparent member (glass) / 112…Reading section (CIS) / 113…Shaft section / 141…Transport guide (rotation guide) / 147…Cover unit (upper cover) / 147a…First rotation axis (support part) / A1…Second rotation axis / A2…Third rotation axis

Claims

[Claim 1] An image reading device that reads image information from a sheet, A cover unit is provided so as to be rotatable around a first pivot axis and constitutes the upper surface of the image reading device, A sheet conveying means for conveying the aforementioned sheet along a sheet conveying path, A conveying guide for guiding a sheet being conveyed by the sheet conveying means, the conveying guide being rotatable around a second pivot axis different from the first pivot axis, A reading unit comprising a transparent member and a reading unit that reads an image of a sheet being transported by the sheet transport means through the transparent member, wherein the reading unit is rotatably mounted around a third pivot axis different from the first pivot axis and the second pivot axis, An interlocking mechanism that rotates the reading unit in conjunction with the rotation of the transport guide, Equipped with, The cover unit is rotatable between a closed position in which it forms part of the sheet transport path together with the transport guide, and an open position in which it opens part of the sheet transport path. An image reading device characterized in that, when the cover unit is in the open position, the reading unit rotates in conjunction with the transport guide by the interlocking mechanism, thereby exposing the transparent member to the outside of the image reading device.

Images