JP2002218161A - Image reader and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader and an image forming device with excellent quality that prevent deterioration in a read image caused by a cable through which an image signal is transmitted. SOLUTION: A cable 108e through which an image signal is transmitted in a contact image sensor 108 is bent around a connection part with the substrate of the contact image sensor 108 so as to be placed under a 1st size index 201.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus and an image forming apparatus, such as a copying machine and a facsimile, provided with a contact image sensor.

[0002]

2. Description of the Related Art Conventionally, in a copier, a multi-function machine having a copying function and a facsimile function, or an image scanner, a contact image sensor (CIS) is brought into close contact with the back surface of the platen glass. 2. Description of the Related Art A device that reads a document image of a document is known.

[0003] This contact type image sensor will be described with reference to FIGS. 8 and 9. FIG. 8 is a schematic perspective view of the contact image sensor, and FIG. 9 is a schematic sectional view of the contact image sensor.

The contact type image sensor 1 has a light source L
An ED 10 and a light guide 11 for guiding light from the LED 10 to a document are provided. The LED 10 is fixed to one end in the longitudinal direction of the light guide 11 (one is provided on the near side in the illustrated example), and light emitted from the LED 10 is repeatedly reflected in the light guide 11. By proceeding, light is emitted from the entire length of the light guide 11 toward the document.

As shown in FIG. 9, the light emitted from the light guide 11 irradiates the original D on the original platen glass 2 and the reflected light is transmitted through the selfoc lens array 12 to a one-dimensional light receiving device such as a CCD. An image is formed on the element array 13.

The reflected light is photoelectrically converted by the one-dimensional light receiving element array 13 to convert image information into electronic information, and the image signal of the original image is transmitted to an image processing unit provided in the apparatus main body.

FIG. 10 is a schematic layout diagram of each component viewed from the back side of a contact type image sensor according to the prior art.

As shown in the figure, a substrate 1c on which a one-dimensional light receiving element array 13 and the like are mounted is provided on the back side of a frame (housing) 1b of the contact type image sensor 1. A flexible flat cable (hereinafter, simply referred to as a cable) 1e for transmitting an image signal (electronic information of an image) is connected to the board 1c via a connector 1d.

Here, in general, due to electronic components mounted on the substrate and other restrictions, the length of the substrate 1c in the width direction (longitudinal direction) and the image reading range of the maximum original size are shown in FIG.
As shown in FIG.

[0010]

In the case of the above prior art, the following problems have occurred.

FIGS. 11A and 11B schematically show the arrangement of each member in a reading section of an image reading apparatus according to the prior art. FIG. 11A is a schematic arrangement view from above, and FIG. It is the typical arrangement figure seen from the side surface side ((a) middle P direction side).

As described above, the substrate 1 in the width direction
Since the length c and the reading range are substantially equal, the cable 1e extending from the connector 1d connected to the substrate 1c is also arranged in the image reading range. That is, as shown in FIG. 11, the cable 1e is disposed below the range on the document table glass 2 where the document can be placed.

Here, when performing fixed reading, that is, when reading an image by placing a document on the platen glass 2, the contact type image sensor 1 moves along the guide shaft 3 to read the document image. Since the scanning is performed, the cable 1e must also follow the contact type image sensor 1. In the drawing, reference numeral 1f denotes a spacer for positioning a distance from the platen glass 2.

Also, due to the space limitation of the apparatus, the space where the cable 1e is arranged cannot be so large.

Therefore, as shown in FIG. 11 (b), the cable 1e is arranged in contact with the lower surface of the platen glass 2, and when the contact type image sensor 1 moves, the cable 1e moves up and down. In such a case, the sheet slides along the lower surface of the original platen glass 2 because the sheet follows the sheet so as to be folded in the direction.

Accordingly, the lower surface of the original table glass 2 may be stained or damaged by the cable 1e, thereby causing a deterioration in the quality of the read image.

FIG. 12 shows a configuration in which the cables are arranged so that the cables do not slide on the lower surface of the platen glass.

FIGS. 12A and 12B schematically show the arrangement of each member in a reading section of an image reading apparatus according to the prior art. FIG. 12A is a schematic arrangement view from above, and FIG. It is the typical arrangement figure seen from the side surface side ((a) middle P direction side).

That is, as shown in FIG. 12, the cable 1e is bent so as to be perpendicular to the platen glass 2 and is arranged so as to surround the image reading range, so that the contact type image sensor is provided. When the cable 1 moves, the cable 1e follows in a wavy manner in the horizontal direction, so that sliding contact with the lower surface of the document table glass 2 can be prevented.

However, in such an arrangement, since the cable 1e becomes long, a disturbance is apt to occur when transmitting electronic information, and this also causes the quality of the read image to deteriorate. Was.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide an excellent quality for preventing deterioration of a read image due to a cable for transmitting an image signal. To provide an image reading apparatus and an image forming apparatus.

[0022]

In order to achieve the above object, an image reading apparatus according to the present invention comprises a platen glass on which a document is placed, and a glass platen provided on the platen glass. A size index indicating the position where the original is placed,
An image reading apparatus comprising: a contact image sensor that reads a document image while being in close contact with the back surface of the platen glass; and a cable that is connected to the contact image sensor and transmits an image signal of the read document image. The cable is wired in a region where the size index is provided.

Therefore, even if the lower surface of the glass is stained or damaged by the cable abutting (sliding) on the lower surface of the original platen glass, the area is provided with the size index. Thus, the quality of the read image is not adversely affected.

In the area where the size index is provided, it is preferable to provide an interposition member between the cable and the platen glass to prevent the cable from coming into contact with the platen glass.

Preferably, the cable is a flexible flat cable.

In the image forming apparatus of the present invention,
It is characterized by comprising the above-mentioned image reading device and image forming means for forming an image read by the image reading device on a sheet.

[0027]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The materials, shapes, relative arrangements, and the like are not intended to limit the scope of the present invention only to them unless otherwise specified.

(First Embodiment) An image reading apparatus and an image forming apparatus according to an embodiment of the present invention will be described with reference to FIGS. In the following description, a copying machine will be described as an example of an image forming apparatus.

FIG. 1 is a perspective view of the image forming apparatus according to the embodiment of the present invention as viewed from the front, FIG. 2 is a perspective view of the image forming apparatus according to the embodiment of the present invention, and FIG. FIG. 4 is an enlarged perspective view of an image reading unit.

First, a schematic configuration of the entire image forming apparatus will be described.

1, 2 and 3, reference numeral 101 denotes an apparatus main body; 102, an ADF (auto document feeder) pressure plate for stacking a plurality of sheet originals, separating and conveying them one by one; An image reading unit that reads image information of a book document on a platen glass;
An image forming apparatus main body 104 employs an electrophotographic printer system using an LED array, and an operation unit 105 includes a display unit and input keys.

Reference numeral 106 denotes a document table on which a document is placed in the case of performing a flow reading, reference numeral 107 denotes a platen glass on which a document is mounted in the case of performing a fixed reading, 108 denotes a contact image sensor, and 109 denotes a flow reading. This is a flow-reading glass that is used when performing.

Reference numeral 110 denotes an LED head unit for forming a latent image on a photosensitive drum; 111, an image forming unit provided with image forming means (photosensitive drum and the like) for forming an image according to a known electrophotographic process; Reference numeral 112 denotes a cassette sheet feeding unit on which sheets (recording paper or the like) for forming an image are stacked and which separates and feeds the sheets one by one; and 113, a plurality of sheet materials P can be stacked on the upper portion of the image forming apparatus main body 104. Is a sheet discharge unit configured as described above.

Reference numeral 114 denotes a cartridge cover for opening the inside of the image forming unit 111 when a component such as a photosensitive drum or the like is formed into a cartridge, and 115 denotes a sheet conveying path inside the ADF. ADF separation unit 116, a paper discharge conveyance unit that discharges and conveys the original at the time of moving reading, 117 a document discharge unit that discharges the flow-read original, and 118 a book document at the time of fixed reading Is a document pressing plate for pressing the document.

Reference numeral 119 denotes a junction between the image reading unit 103 and the main body 104 of the image forming apparatus; 120, a control unit of the facsimile apparatus; 121, a sheet original conveying unit for conveying a sheet original at the time of scanning; A double-sided conveyance section cover for opening a conveyance path for performing image formation on both sides of the sheet, a conveyance direction switching section 123 for switching a sheet conveyance direction for performing image formation on both sides of a sheet, and a image formation timing 124. A resist transport unit 125 for transporting the sheet while measuring is provided. Reference numeral 125 denotes an MP (multi-paper) paper feed unit disposed inside the image forming apparatus main body 104.

Next, fixed reading (reading of book original)
Will be described.

The ADF pressure plate 102 is rotatably attached to the image reading unit 103 via a hinge 102a. One hinge portion 102a is provided on each of the left and right sides on the rear side of the apparatus (the left side is not shown), and can be opened and closed by lifting the front side of the ADF pressure plate 102 (see both arrows in FIG. 2).

The hinge portion 102a can stop the ADF pressure plate 102 in an open state up to a predetermined angle (for example, 70 °) by a combination of a damper, a cam, a spring member, and the like. When the ADF pressure plate 102 is open, a document can be set on the document table glass 107.

The basic structure of the contact type image sensor 108 is the same as that described in the above prior art.
The light from the LED, which is a light source, is guided by a light guide made of resin or the like, the guided light is applied to the image information surface (original surface) of the original, and the reflected light reflected by the image information surface is used as an image forming means. The image information is read by forming an image on a one-dimensional sensor element array provided with a plurality of photoelectric conversion elements by a Selfoc lens (trademark).

As shown in FIG. 4, the contact-type image sensor 108 is movable in the left-right direction of the apparatus along a guide shaft 103c, and is driven by a timing belt 103a, a driving pulley 103b, a driving motor (not shown), and the like. Can be moved to the position. In this case, the contact image sensor 108 is supported by the guide shaft 103c via the carriage 103d, and the spring 103
and is biased upward by e.

A contact type image sensor 108 is provided between the contact type image sensor 108 and the platen glass 107.
A spacer 108 a for determining the distance from the platen 107 to the platen glass 107 is inserted. Then, the contact image sensor 108 moves at a constant speed in a predetermined range from the book reading range start position 107a to the book reading range end position 107b to read the image of the document placed on the platen glass 107. Has become.

A white sheet 109c is provided on the lower surface of a jump table 109b projecting above the document table glass 107, and performs shading correction of the contact image sensor 108 when the reading position of the contact image sensor 108 is below the white sheet 109c. Do. When performing a book scan, the contact-type image sensor 108 passes under the jump table 109b each time scanning is performed, so that shading correction can be performed each time scanning is performed. This is effective for reducing the influence of the light source of the contact type image sensor 108 in which the light amount changes according to the temporal change of the light source.

The original holding plate 118 is formed by laminating white sheets, sponges, and the like.
07 is prevented from floating. Document holding plate 1
Reference numeral 18 denotes a book reading range start position 107a at the left end 118a.
And the right end 118b are the book reading range end position 107
It extends to the right side of b.

Next, the flow reading (reading of a sheet document) will be described.

The ADF separation unit 115 includes a pickup roller 115a, a separation roller 115b, and a separation roller 115b which are vertically movable by an actuator (not shown).
And a retard roller 115c that rotates in the opposite direction while being pressed against.

First, a table (front) is placed on the document table 106.
The sheet document stacked face up is pressed by lowering the pickup roller 115, and the separation roller 115b is pressed.
The sheet is fed between the retard rollers 115c and separated one by one by a separation roller 115b pressed against the retard roller 115c. Next, the U-turn paper path is transported along the document guide 121d by the reading transport roller 121c pressed against the separation transport rollers 121a and 121b pressed by a pressing spring (not shown).

Next, the sheet original is conveyed to the flow reading glass 109, and the sheet original is pressed against the flow reading glass 109 by the sheet original pressing plate 121e pressed by an urging spring (not shown) and is conveyed while being brought into close contact therewith.

Here, the contact type image sensor 108 is fixed to the sheet original reading position 109a, and the contact original image sensor 108
9a, the image information on the front side of the sheet document moving on the surface is read.

Next, the sheet document D is placed on the jump table 109.
b returns to the ADF pressure plate 102 side, and the reading and conveying roller 1 pressed against the reading and conveying roller 121f pressed by the pressing spring.
It is conveyed by 21c.

Further, the sheet is discharged onto the document discharge tray 117c by the discharge roller 117b pressed against the discharge roller 117a pressed by the pressing spring. Discharge roller 117b
A read stamp 121g is provided on the upstream side of, and can be stamped on the surface of the sheet document.

The document placing table 106 is fixedly disposed on the ADF pressure plate 102. The document placing table 106 has a slider 106a slidable in a direction perpendicular to the sheet document conveying direction (the width direction of the sheet document D). Is provided. The slider 106a can align both sides of the sheet document stacked on the document table 106.

A document length sensor 106b is provided on the document table 106, and can detect the length of a set sheet document. Also, the ADF separation unit 115
The presence / absence and width of a sheet document can be detected by a plurality of document width sensors 115d arranged in the width direction of the sheet document. Document width sensor 115d and document length sensor 10
The document size and the setting direction can be detected based on the combination of the detection outputs 6b.

The sheet document transport section 121 is provided with a document feed sensor 121h and a document end sensor 121i. The document feed sensor 121h detects whether the sheet document has been fed out from the ADF separation unit 115 or detects the passage of the rear end of the sheet document. The document edge sensor 121i detects the passage of the leading edge and the trailing edge of the sheet document, and its output is used for reading timing control.

Next, the arrangement of each member constituting the image reading section according to the present embodiment will be described with reference to FIGS. 5 and 6. FIG. FIG. 5 is a schematic layout diagram of each configuration viewed from the back side of a contact image sensor, which is a main configuration of the image reading apparatus. FIG. 6 shows the first embodiment of the present invention.
FIGS. 4A and 4B schematically show the arrangement of each member in a reading unit of the image reading apparatus according to the embodiment, FIG. 4A is a schematic layout viewed from above, and FIG. a) Medium Q
FIG.

As shown, the contact type image sensor 10
A substrate 108c on which a one-dimensional light receiving element array or the like is mounted is provided on the back surface side of the eight frames (housing) 108b.

A flexible flat cable (hereinafter simply referred to as a cable) 108e for transmitting an image signal (electronic information of an image) is provided on the substrate 108c.
Are connected via a connector 108d.

In the present embodiment, the cable 108e is bent in the vicinity of the connection portion with the board 108c, so that the cable 108e
The wiring is arranged (arranged) outside the image reading range and in a region where the size index is provided.

That is, due to the electronic components mounted on the substrate 108c and other restrictions, the substrate 1 in the width direction (longitudinal direction) is not used.
The length of 08c and the image reading range of the maximum original size are substantially the same as shown in FIG.

Therefore, if the cable 108e is directly extended from the connector 108d connected to the board 108c, the cable 10e is not moved within the image reading area as in the prior art.
Since 8e abuts on the platen glass, the space for setting the size index provided outside the image reading range is effectively used.

That is, the document table of the image reading apparatus is provided with a size index indicating the position where the document is placed according to the document size. More specifically, as shown in FIG.
At one end in the width direction of the image reading area, a first size index 201 indicating the position in the length direction of the document is provided. At one end in the length direction of the image reading area, the position in the width direction of the document is indicated. A second size index 202 shown is provided.

Normally, the first size index 201 is provided on the platen glass 107. The area where the first size index 201 is provided is, of course, outside the image reading area.

Therefore, in the present embodiment, as described with reference to FIG.
As shown in FIG. 6, the cable 108e has a bent shape in the vicinity of the connection portion with the cable 108e.
It is arranged below the size index 201.

With such an arrangement,
The cable 108e abuts on the lower surface of the platen glass 107 below the first size index 201,
When the close contact type image sensor 108 moves, it comes into sliding contact with the lower surface of the original platen glass 107, so that the lower surface of the original platen glass 107 may be stained or damaged.

However, even if this portion becomes dirty or damaged, since it is outside the image reading area, the quality of the read image is not adversely affected, and stable image quality can be maintained.

Further, unlike the case where the cable is arranged perpendicular to the platen glass, it is not necessary to lengthen the cable, so that disturbance when transmitting an image signal by the cable can be suppressed, and a stable image can be obtained. Quality can be maintained.

(Second Embodiment) An image reading apparatus according to a second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a schematic arrangement view of an arrangement configuration of each member in a reading unit of an image reading apparatus according to a second embodiment of the present invention, as viewed from a side.

In the first embodiment, the cable 10
A case has been described where 8e is configured to be bent (disposed) outside the image reading range as a bent shape near a connection portion with the substrate 108c.

However, there may be cases where the entire width of the cable 108e in the width direction cannot be completely located outside the image reading range due to restrictions on the size and shape of the substrate, the cable, the size index, and the like.

Therefore, in the present embodiment, a mylar 203 as an interposition member is adhered to a region below the platen glass 107 and in which the first size index 201 is provided.

By attaching the mylar 203 in this manner, even if a part of the cable 108e in the width direction is arranged in the image reading area, a gap is formed between the cable 108e and the platen glass 107, There is no contact or sliding contact with the glass 107.

As a result, the cable 108e does not stain or damage the platen glass 107, so that stable image quality can be maintained.

[0072]

As described above, according to the present invention, when the cable for transmitting the image signal is wired in the area where the size index is provided, the lower surface of the glass is stained or damaged by the cable. Even in the region where the size index is provided, the quality of the read image is not adversely affected, and the quality of the read image is excellent because the deterioration of the read image can be prevented.

In the area where the size index is provided,
By providing an interposition member between the cable and the platen glass to prevent the cable from coming into contact with the platen glass, the cable can be prevented from soiling or damaging the platen glass.

[Brief description of the drawings]

FIG. 1 is a perspective view of an image forming apparatus according to an embodiment of the present invention as viewed from the front.

FIG. 2 is a perspective view of the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is an enlarged perspective view of an image reading unit in the image forming apparatus according to the embodiment of the present invention.

FIG. 4 is an internal structural diagram of an image reading unit in the image forming apparatus according to the embodiment of the present invention.

FIG. 5 is a schematic layout diagram of each configuration as viewed from the back surface side of the contact image sensor according to the first embodiment of the present invention.

FIG. 6 is an arrangement configuration diagram of each member in a reading unit of the image reading apparatus according to the first embodiment of the present invention.

FIG. 7 is an arrangement configuration diagram of each member in a reading unit of an image reading device according to a second embodiment of the present invention.

FIG. 8 is a schematic perspective view of a contact image sensor.

FIG. 9 is a schematic sectional view of a contact image sensor.

FIG. 10 is a schematic layout view of each configuration as viewed from the back side of a contact image sensor according to the related art.

FIG. 11 is a schematic configuration diagram of each member in a reading unit of an image reading apparatus according to the related art.

FIG. 12 is a schematic layout diagram of each member in a reading unit of an image reading apparatus according to the related art.

[Explanation of symbols]

 103 Image Reading Unit 104 Image Forming Apparatus Main Body 106 Document Placement Table 107 Document Placement Glass 108 Contact Image Sensor 108a Spacer 108b Frame 108c Board 108d Connector 108e Cable (Flexible Flat Cable) 111 Image Forming Unit 201 First Size Index 202 Second Size Indicator 203 Myra

Continued on the front page F-term (reference) 5C051 AA01 BA04 DB04 DB06 DB35 DC07 5C062 AB17 AD06 5C072 AA01 EA07 FA05 LA02

Claims (4)

[Claims] An original platen glass on which an original is placed; a size index provided on the platen glass indicating a position on which the original is to be placed according to the original size; An image reading apparatus comprising: a contact image sensor that reads an original image; and a cable connected to the contact image sensor and transmitting an image signal of the read original image. An image reading device, which is wired in an area provided. 2. An interposition member for preventing the cable from coming into contact with the original platen glass in the area where the size index is provided, between the cable and the original platen glass. The image reading device according to claim 1. 3. The image reading apparatus according to claim 1, wherein the cable is a flexible flat cable. 4. An image forming apparatus comprising: the image reading apparatus according to claim 1, 2, or 3; and an image forming unit that forms an image read by the image reading apparatus on a sheet. .