Image reading device and image forming device

Abstract

The present application provides an image reading device and an image forming device which do not cause the device to be large, and prevent the occurrence of the flexible cable being wound by the optical scanning unit. The image reading device (102) is provided with a contact glass (7) as a reading surface of a placed original, an optical scanning unit (16), and a flexible cable (30) having a curved cross-sectional shape between the inner side bottom surface of the contact glass (7) frame (4) and a fixed portion (21), one end of which is connected to the optical scanning unit (16), and the other end of which is connected to the fixed portion (24). The flexible cable (30) has a load member (24) which makes the flexible cable (30) flex to form a recess (33) at a position (23) which is substantially the center of a separation distance (L2) in the horizontal direction from a holding portion (22) of the original position of the optical scanning unit (16) to the fixed portion (24). The load member (24) is made of a material which is close to the position on the triboelectric series of the material constituting the surface of the flexible cable (30).

Description

Technical Field

[0001] The present invention relates to an image reading device and an image forming device. Background Art

[0002] Image reading devices include those installed in image forming devices such as fax machines, copiers, or multifunction peripherals that combine printer and scanner functions, or those used independently as image reading devices. In addition to reading an original document by moving it relative to a fixed reading optical system, there are also scanning methods that use a moving optical system to read an original document placed on a loading table. Among the latter methods, a known configuration involves moving a carriage equipped with a reading element positioned in the main scanning direction in a sub-scanning direction within a frame housing the reading device that houses the carriage.

[0003] A known configuration includes a flexible flat cable (FFC) (hereinafter referred to as a "flexible cable") as a medium for transmitting and receiving carriage reading signals and carriage driving power to and from the device main body. A known device has a configuration in which one end of the flexible cable is fixed to the carriage and the other end is fixed to the main body. During scanning, the flexible cable moves while bending between the contact glass serving as the document loading portion and the main body (see, for example, Patent Document 1).

[0004] In an image reading device that has been miniaturized in the height direction, a flexible cable is configured to contact the contact glass. In this configuration, as the carriage moves back and forth in the sub-scanning direction, the flexible cable frequently and repeatedly comes in and out of contact with the contact glass. This repetitive movement can damage the flexible cable. Furthermore, static electricity generated by friction can cause the flexible cable to adhere to the bottom surface of the contact glass, potentially entangled in the moving optical scanning unit. Furthermore, debris or dust from the flexible cable can adhere to the contact glass, potentially hindering reading. When the surface of the contact glass becomes contaminated, noise can be incorporated into the read signal, significantly reducing image quality.

[0005] In contrast, Patent Document 1 discloses a configuration in which a separation mechanism is provided to prevent a bent portion of a flexible cable from coming into contact with a contact glass.

[0006] Patent Document 1 discloses a mechanism for separating the flexible cable from the contact glass. The mechanism includes a shaft fixed to multiple locations on the flexible cable and rollers attached to both ends of the shaft. Another mechanism includes two rollers disposed opposite each other with the flexible cable sandwiched therebetween, a connecting member for the rollers, and a guide. However, each of these separation mechanisms is complex, leading to increased costs.

[0007] On the other hand, in order to prevent the flexible cable from coming into contact with the contact glass, a separation distance between the two must be ensured, which leads to a problem of increasing the size of the image reading device.

[0008] On the other hand, if the contact area and contact time can be reduced without completely separating the flexible cable from the contact glass, the generation of static electricity can be reduced, thereby preventing the above-mentioned problems, especially the flexible cable being caught in the optical scanning unit.

[0009] Therefore, an object of the present invention is to provide an image reading device that can prevent a flexible cable from being entangled in an optical scanning unit without increasing the size of the device.

[0010] [Patent Document 1] (Japanese Patent Application Laid-Open No. 5-34838) Summary of the Invention

[0011] To solve the above-mentioned problems, the present invention relates to an image reading device, characterized by comprising: a contact glass serving as a reading surface for a loaded document; an optical scanning unit having an image sensor that moves within a reading area of ​​the contact glass to read the document; a carriage that holds the image sensor so as to be movable in a sub-scanning direction; and a flexible cable having one end connected to the optical scanning unit and the other end connected to a fixing portion on the inner bottom surface of a housing that houses the optical scanning unit, the flexible cable having a curved cross-sectional shape between the contact glass and the inner bottom surface of the housing. The carriage has a holding portion for holding the flexible cable on a front side surface that forms a forward path in the sub-scanning direction. The flexible cable is provided with a load member that bends the flexible cable to form a recessed portion at a position at the center of a horizontal separation distance from the holding portion to the fixing portion in a home position of the optical scanning unit. The load member is made of a material that is close in position to a material constituting a surface of the flexible cable in a triboelectric system.

[0012] According to the present invention, it is possible to provide an image reading device that can prevent a flexible cable from being entangled in an optical scanning unit without increasing the size of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 FIG. 1 is a schematic diagram showing the external appearance of an example of an image forming apparatus according to an embodiment of the present invention.

[0014] Figure 2 FIG. 1 is an example of an image forming apparatus according to an embodiment of the present invention. Figure 1 FIG. 1 is a schematic diagram showing the configuration of a scanning and reading section of an image forming apparatus.

[0015] Figure 3 Shown is Figure 2 A schematic cross-sectional view of XX of the scanning and reading portion.

[0016] Figure 4 Shown is Figure 3 A partial enlarged view of .

[0017] Figure 5 (A) and (B) are schematic diagrams showing an example of an adjustment mechanism for adjusting the length of a flexible cable. DETAILED DESCRIPTION

[0018] The image reading device and image forming device of the present invention are described below with reference to the accompanying drawings. The present invention is not limited to the embodiments described below; other embodiments, additions, corrections, deletions, and the like are possible within the scope of those skilled in the art. Any such modifications, as long as they achieve the functions and effects of the present invention, are within the scope of the present invention.

[0019] Figure 1 FIG2 is a schematic diagram of the external appearance of an embodiment of an image forming apparatus including an image reading device according to the present invention. Furthermore, the image reading device, described later, may be applied to an image scanner, and the image forming apparatus may be applied to a copier or facsimile machine including an image scanner, or further to a multifunction peripheral device including a copying function and a facsimile function.

[0020] exist Figure 1 The image forming apparatus of this embodiment includes an image forming unit 101, a scanning and reading unit 102 as an image reading device according to the present invention, and an automatic document feeder (hereinafter also referred to as “ADF”) 103.

[0021] The ADF 103 is attached to the scanning and reading unit 102 via an opening and closing mechanism such as a hinge so as to be openable and closable.

[0022] The image forming unit 101 constitutes an image forming mechanism, including an exposure device (not shown), multiple photosensitive drums, a developing device with colorants of different colors (cyan (C), yellow (Y), magenta (M), black (Bk)) arranged around each photosensitive drum, a transfer belt, and a fixing device.

[0023] Based on the image information read by the scanning and reading section 102 and decomposed by color, images are formed separately by color on multiple photosensitive drums. After the colorant on the photosensitive drum is transferred and overlapped on the recording paper supplied from the paper supply section, the colorant of the colorant image transferred to the recording paper is melted by the fixing device, thereby fixing the color image on the recording paper.

[0024] Figure 2 FIG. 1 is an example of an image forming apparatus according to an embodiment of the present invention. Figure 1 FIG. 2 is a schematic diagram showing the configuration of the scanning and reading unit 102 of the image forming apparatus.

[0025] like Figure 2 As shown, the image reading device (scanning and reading section) 102 of this embodiment includes a contact glass 7 as a reading surface for a placed document and an optical scanning unit 16 within a housing 4 .

[0026] The optical scanning unit 16 includes an image sensor that moves in the reading area W of the contact glass 7 to read the document, and a carriage that holds the image sensor so that it can move in the sub-scanning direction (the direction of arrow B in the figure). The image sensor has a main scanning direction as its longitudinal direction (the direction of arrow A in the figure).

[0027] Specifically, the optical scanning unit 16 includes a charge coupled device (CCD), a light source, a lens, and a reflective mirror as an image sensor, and reads a two-dimensional color image of the document placed on the contact glass 7 by moving the optical scanning unit 16 in the sub-scanning direction (direction B) via a driving mechanism (not shown).

[0028] The electric signal as the read information is sent via a cable from the substrate including the CCD mounted on the optical scanning unit 16 to the main body side substrate provided on the inner bottom side of the housing 4. As the cable, a flexible cable suitable for space saving is used.

[0029] Figure 1 The ADF 103 shown includes, for example, a document tray and a paper feed unit composed of various rollers, etc., which separates documents one by one from a bundle of documents placed on the document tray and feeds them to the contact glass 7. Furthermore, the ADF 103 includes a paper discharge unit composed of various rollers, etc., and the document on the contact glass 7 is scanned by the optical scanning unit 16 of the scanning and reading unit 102 and then discharged to the paper discharge tray.

[0030] The ADF 103 also functions as a document pressing portion that presses and fixes the document on the contact glass 7 when the optical scanning unit 16 moves in the sub-scanning direction (B direction) to read the document placed on the contact glass 7 .

[0031] The contact glass 7 is provided on the upper portion of the housing 4 of the scanning and reading unit 102 and constitutes the upper surface of the housing 4 .

[0032] Figure 3 Shown is Figure 2 A schematic diagram of the XX cross section of the scanning reading unit 102 is shown. Figure 4 Shown is Figure 3 A partial enlarged view of .

[0033] The optical scanning unit 16 is connected to the optical scanning unit 16 by Figure 3 and Figure 4The predetermined home position (standby position) shown is moved in the sub-scanning direction to read the original document.

[0034] like Figure 3 and Figure 4 As shown, a flexible cable 30 for power supply or signal transmission and reception is connected to the optical scanning unit 16 .

[0035] One end of the flexible cable 30 is connected to the substrate 17 of the optical scanning unit 16, and the other end is connected to a fixing portion 21 on the inner bottom surface of the housing 4 that houses the optical scanning unit 16. The flexible cable 30 has a curved cross-section between the contact glass 7 and the inner bottom surface of the housing 4. The fixing portion 21 is electrically connected to a main body-side substrate provided on the housing 4.

[0036] The carriage of the optical scanning unit 16 has a holding portion 22 for holding the flexible cable 30 on a surface on the front side that becomes the outward path in the sub-scanning direction.

[0037] The flexible cable 30 is provided with a load member 24 at a position 23 approximately in the center of the horizontal separation distance L2 between the holding portion 22 and the fixing portion 21 in the original position of the optical scanning unit 16. The load member 24 is configured to bend the flexible cable 30 to form a recess 33 (in the figure, L3 = L2 / 2).

[0038] By including the load member 24, the flexible cable 30 can bend without being affected by the rigidity of the rising portion 31 extending from the fixing portion 21, thereby forming the recessed portion 33. Without the load member 24, the entire region of the flexible cable 30 facing the contact glass 7 is convex, and contacts the contact glass 7 over a wide area.

[0039] In contrast, in this embodiment, a recess 33 is formed substantially in the center of the convex portion, and there are two or more convex portions including the convex portions (3234) formed on both sides of the recess 33, so that the contact area between the flexible cable 30 and the contact glass 7 becomes smaller.

[0040] The flexible cable 30 is preferably arranged in a position that is invisible or difficult to see from the outside by the user, etc. When the optical scanning unit 16 reciprocates in the sub-scanning direction B, the influence of the flexible cable 30 contacting the contact glass 7 can be reduced.

[0041] The load member 24 is made of a material that is close in position to the material constituting the surface of the flexible cable 30 in terms of the frictional charging system. This can reduce or prevent the generation of static electricity.

[0042] Since the surface of the flexible cable 30 is generally covered with a material containing polyester fiber, the material of the load member 24 is preferably composed of a material containing polyester fiber, polycarbonate, ABS resin, polystyrene, polyurethane resin, polypropylene, vinyl chloride resin, and silicone resin.

[0043] In addition, Figure 3 and Figure 4 In the example shown in FIG, the load member 24 is provided on the upper surface of the flexible cable 30 (the surface facing the contact glass 7), but the present invention is not limited thereto. The load member 24 may be provided on any surface of the flexible cable 30 as long as the flexible cable 30 can be bent in a direction away from the contact glass 7 to form the recess 33.

[0044] The load member 24 may be detachably provided with respect to the flexible cable 30 or may be bonded and fixed by an adhesive or the like.

[0045] With this configuration, it is possible to prevent the moving optical scanning unit 16 from being caught in the flexible cable 30 .

[0046] In addition, the fixing portion 21 is preferably disposed at a position substantially in the center of the scanning range L in the sub-scanning direction B of the optical scanning unit 16. Figure 3 and Figure 4 In the equation, L2=L / 2.

[0047] The load member 24 and the recess 33 of the flexible cable 30 formed by the load member 24 preferably do not contact the contact glass 7 and the inner bottom surface of the frame 4 , and are displaced along with the movement of the optical scanning unit 16 in the sub-scanning direction B.

[0048] When the recess 33 contacts the inner bottom surface of the frame 4, the flexible cable 30 may be caught under the moving optical scanning unit 16. To prevent this, it is preferable to adjust the weight of the load member 24 and / or the length of the flexible cable 30.

[0049] To adjust the length of the flexible cable 30, for example, Figure 3 and Figure 4 As shown, a mode can be adopted in which the carriage of the optical scanning unit 16 includes an adjustment mechanism 26 for adjusting the length between the holding portion 22 and the fixing portion 21 of the flexible cable 30 .

[0050] 1 is a perspective view of an example of an adjustment mechanism for adjusting the length of the flexible cable 30, (A) is a perspective view of an example screw component (length adjustment screw) 26, and (B) is a perspective view of an example of a state in which the flexible cable 30 is wound around the screw component.

[0051] In the present embodiment, the adjustment mechanism is a screw member 26 that can wind up the flexible cable 30 by rotating it.

[0052] The screw member 26 includes a screw portion 29 that is rotatably screwed into a screw hole (not shown) provided in the carriage, a shaft portion 28 around which the flexible cable 30 can be wound, and a hook portion 27 .

[0053] like Figure 3 and Figure 4 , (B) shows a state in which the flexible cable 30 is inserted into the screw member 26. By rotating the screw member 26 in this state, the flexible cable 30 can be wound or rewound, and the length of the flexible cable 30 can be appropriately adjusted.

[0054] According to the image reading device of this embodiment, the flexible cable 30 can be prevented from being entangled in the optical scanning unit 16 with a simple configuration without increasing the size of the device to separate the flexible cable 30 from the contact glass 7 .

Claims

1. An image reading device, characterized in that include: a contact glass serving as a reading surface for a placed original document; an optical scanning unit including an image sensor that moves in a reading area of ​​the contact glass and reads an original document, and a carriage that holds the image sensor so as to be movable in a sub-scanning direction; and a flexible cable having one end connected to the optical scanning unit and the other end connected to a fixing portion on the inner bottom surface of a frame housing the optical scanning unit, and having a curved cross-sectional shape between the contact glass and the inner bottom surface of the frame; The carriage has a holding portion for holding the flexible cable on a front side surface that becomes a forward path in the sub-scanning direction. The flexible cable is provided with a load member that bends the flexible cable to form a recessed portion at a position in the middle of a horizontal separation distance from the holding portion to the fixing portion in the original position of the optical scanning unit. The load member is made of a material that is close in position to a material constituting the surface of the flexible cable in a triboelectric charging series.

2. The image reading device according to claim 1, wherein: The flexible cable has two or more convex portions on both sides of the concave portion formed by the load member.

3. The image reading device according to claim 1, wherein: The fixing portion is arranged at a position that becomes the center of a scanning range of the optical scanning unit in the sub-scanning direction.

4. The image reading device according to claim 1, wherein: The load member and the recessed portion of the flexible cable formed by the load member are not in contact with the contact glass and the inner bottom surface of the housing, and are displaced along with the movement of the optical scanning unit in the sub-scanning direction.

5. The image reading device according to claim 1, wherein: The slider includes an adjustment mechanism for adjusting a length between the holding portion and the fixing portion of the flexible cable.

6. The image reading device according to claim 5, wherein: The adjustment mechanism is a screw member capable of winding up the flexible cable by rotating it.

7. The image reading device according to claim 1, wherein: The surface of the flexible cable is composed of a material containing polyester fibers, The load member is made of a material including any one of polyester fiber, polycarbonate, ABS resin, polystyrene, polyurethane resin, polypropylene, vinyl chloride resin, and silicone resin.

8. An image forming apparatus, characterized in that: An image reading device according to any one of claims 1 to 7.

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