Image reading device

Abstract

To provide an image reading device to be used in a copying machine, an image scanner, a multifunction printer, etc., and more particularly to a scanning guide member of a reading unit.SOLUTION: An image reading device includes a reading unit (202) for reading image information of a document (200), driving means (203) for moving the reading unit in a sub-scanning direction, a guide member (204) for guiding the reading unit in the sub-scanning direction, and a housing (205) for accommodating the reading unit therein. The guide member is formed by bending a metal plate, and has fitting holes (102) (103) in two side walls (100) (101) on the sub-scanning direction side of the housing. Front and rear end portions of the guide member are provided with circular engagement portions (104) (105) that engage with the fitting holes provided in the side walls, and the guide member is positioned with respect to the housing.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image reading device used in a copying machine, an image scanner, a multifunction printer, etc., and more particularly to a scanning guide member of a reading unit. [Background technology]

[0002] The image reading device is mainly composed of a platen glass (201) on which an original (200) is placed, a reading unit (202) that reads the image information of the original, a driving means (203) that moves the reading unit in the sub-scanning direction, a guide member (204) that guides the reading unit in the sub-scanning direction, and a housing (205) that contains the above components, and is a device that reads the image of the original placed on the platen glass.

[0003] Examples of the guide member include those using a metal round shaft as disclosed in JP-A-2007-110466 and JP-A-2017-121034.

[0004] Furthermore, the specification of Japanese Patent No. 4757845 discloses the use of a sheet metal frame as a guide member.

[0005] Furthermore, Japanese Patent Nos. 6116147 and 6314607 disclose a configuration in which a protrusion is provided on a resin housing and used as a guide member. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2007-110466 A [Patent Document 2] JP 2017-121034 A [Patent Document 3] Patent No. 4757845 [Patent Document 4] Patent No. 6116147 [Patent Document 5] Patent No. 6314607 Summary of the Invention [Problem to be solved by the invention]

[0007] Generally, the guide member (204) is mainly a metal round shaft, a sheet metal frame, or a protruding portion of a resin housing, as described in the above patent documents.

[0008] The dimensional accuracy expected for guide members is generally in the following order: metal round shaft > sheet metal frame > plastic housing guide member.

[0009] That is, the reading accuracy of the reading unit (202) also follows the above order.

[0010] On the other hand, when comparing the costs of guide members, the order of increasing cost is generally metal round shaft > sheet metal frame > plastic casing guide member.

[0011] The guide member to be used is determined in consideration of the product specifications of the image reading device (206), such as resolution, scanning speed, durability, and cost.

[0012] However, once the guide member is selected, the shape of the housing (205) that contains it is also determined dynamically according to the mounting shape of the guide member. In other words, the housing has to be newly manufactured for each shape of the guide member, which results in the problem of high costs such as mold costs for the housing.

[0013] Furthermore, since the housing differs for each product specification, there is a problem in that a common design cannot be implemented.

[0014] Furthermore, in order to expand the product lineup, when it becomes necessary to meet higher specifications, such as improving scanning speed, it becomes necessary to replace the guide member with one that has higher precision. However, this requires changing the housing as well, which is an obstacle to expanding the product lineup.

[0015] The present invention has been made based on the above background, and has an object to enable selective use of the guide members and to standardize the housing. [Means for solving the problem]

[0016] In order to solve the above problems, the image reading device of the present invention has a reading unit (202) that reads image information of an original (200), a driving means (203) that moves the reading unit in the sub-scanning direction, a guide member (204) that guides the reading unit in the sub-scanning direction, and a housing (205) that contains the reading unit, and is characterized in that the guide member is formed by bending a metal plate, and two side walls (100) (101) on the sub-scanning direction side of the housing have fitting holes (102) (103), and the front and rear ends of the guide member are provided with circular engagement portions (104) (105) that engage with the fitting holes provided in the side walls, so that the guide member is positioned relative to the housing.

[0017] The guide member is also characterized in that at least one of the front and rear ends has an engagement portion (106) formed by cutting out a part of a circle, and the side wall has an engagement hole (107) formed by cutting out a part of a circle.

[0018] The guide member is also characterized in that separate engagement members (108) are disposed at the front and rear ends thereof to engage with the fitting holes in the side walls. Effect of the Invention

[0019] According to the present invention, fitting holes are provided on two side walls of the housing in the sub-scanning direction, and the front and rear ends of the guide member, which is made by bending plate metal, are provided with circular engagement portions that engage with the side walls, thereby enabling the guide member to be positioned relative to the housing.

[0020] Furthermore, even if the specifications of the image reading device are changed, the scanning speed is increased, and the guide member is changed to a round metal shaft, the guide member can be replaced simply by inserting the round metal shaft into the fitting hole of the housing, which means that the housing can be standardized even if the product specifications are different. [Brief description of the drawings]

[0021] [Figure 1] 1 is a perspective view of an image reading device according to an embodiment of the present invention; [Diagram 2] 1 is a cross-sectional view of an image reading device according to the present invention. [Diagram 3] FIG. 4 is a detailed view of a guide member according to the present invention. [Figure 4] FIG. 4 is a detailed view of a guide member and a housing according to the present invention. [Diagram 5] FIG. 4 is a detailed view of a guide member and a reading unit according to the present invention. [Figure 6] FIG. 4 is a detailed view of another embodiment according to the present invention. [Figure 7] FIG. 4 is a detailed view of another embodiment according to the present invention. [Figure 8] FIG. 4 is a detailed view of another embodiment according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] (First embodiment) FIG. 1 is a perspective view of an image reading device according to the present invention.

[0023] FIG. 2 is a cross-sectional view of an image reading device according to the present invention.

[0024] FIG. 3 is a detailed view of a guide member according to the present invention.

[0025] FIG. 4 is a detailed view of the housing of the present invention.

[0026] FIG. 5 is a view showing the engagement between the guide member and the reading unit of the present invention.

[0027] The reading unit (202) is moved in the sub-scanning direction by a driving means (203) and is configured to read an image of an original (200) placed on the platen glass (201).

[0028] In order to guide the reading unit in the sub-scanning direction, a guide member (204) made by bending a metal sheet such as an electroplated zinc steel sheet into a U-shape is provided, and a sliding member (206) provided on the reading unit is made to follow this guide member to guide and move it in the sub-scanning direction, thereby reading the original.

[0029] The ends of the guide members have circular engagement portions (105) and (106).

[0030] On the other hand, the housing (205) containing the reading unit has circular fitting holes (103) (104) in side walls (101) (102) arranged in the sub-scanning direction, and the guide member is positioned relative to the housing by fitting the engagement portions of the guide member into the holes.

[0031] In the present invention, if an upgrade to product specifications requires replacing the guide member with a metal round shaft, it is sufficient to simply insert the metal round shaft into the fitting hole of the housing. In other words, even if the product lineup expands, it can be accommodated without changing the housing.

[0032] (Second Example) FIG. 6 shows another embodiment of the present invention.

[0033] That is, at least one of the engagement portions of the guide member has an engagement portion (107) with a part of a circle cut out, and at least one of the engagement holes of the housing has an engagement hole (108) with a part of a circle cut out.

[0034] This makes it possible to regulate the rotation of the guide member about the axis of the fitting hole.

[0035] (Third Example) FIG. 7 shows another embodiment of the present invention.

[0036] That is, the guide member has engagement members (109) at both front and rear ends. The guide member is made by bending sheet metal, but a special die is required to finish the sheet metal into a circular shape during bending, so this eliminates the need for a special die and reduces costs. It also makes it possible to provide the engagement members with shapes that are difficult to make by bending sheet metal (such as an E-ring retaining groove). [Industrial Applicability]

[0037] The present invention relates to an image reading device used in a copying machine, an image scanner, a multifunction printer, etc., and more particularly to improving the holding / positioning accuracy of an image sensor. [Explanation of symbols]

[0038] 100 side wall 1 101 Side wall 2 102 Fitting hole 103 Fitting hole 104 Joint part 105 Joint part 106 A part of the yen has been cut off 107 A fitting hole with a part of a circle cut out 108 Separately constructed engagement members 109 Separate joint parts 200 manuscripts 201 Platen Glass 202 Reading unit 203 Driving Means 204 Guide member 205 Case 206 Sliding members

Claims

1. The scanning device includes a scanning unit that scans image information of an original, a driving unit that moves the scanning unit in a sub-scanning direction, a guide member that guides the scanning unit in the sub-scanning direction, and a housing that contains the scanning unit; The guide member is formed by bending a metal plate, The housing has fitting holes in two side walls in the sub-scanning direction, the guide member is provided at its front and rear ends with circular engagement portions which engage with the engagement holes formed in the side walls, thereby positioning the guide member relative to the housing.

2. 2. An image reading device according to claim 1, wherein at least one of the front and rear ends of said guide member has an engagement portion formed by cutting out a part of a circle, and said side wall has a fitting hole formed by cutting out a part of a circle.

3. 3. An image reading apparatus according to claim 1, wherein separate engagement members are disposed at front and rear ends of said guide member for engaging with said fitting holes of said side walls.

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