JP3021059B2 - Original image reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an original image reading apparatus, and more particularly, to an original image reading apparatus which is detachably attached to an image information processing apparatus such as a facsimile or an image scanner and optically reads image information of an original. It is about.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for smaller, lighter, and less expensive image information processing apparatuses such as facsimile machines and image scanners. In particular, as for the facsimile, with the expansion of the home facsimile market for personal use and the like, not only miniaturization, weight reduction and price reduction, but also various demands for design and function have been increased.

A document image reading apparatus mounted on such an image information processing apparatus for optically reading image information of a document is a reduced reading method in which a line sensor such as a CCD and a reduction optical system are combined, and the same as the document width. 1x optical system such as line sensor with length and converging fiber lens array and LED
A contact reading system in which a light source such as an array is integrated into the frame, or a line sensor and a light source are integrated into the frame without using a lens array, and the document is brought close to the line sensor. 2. Description of the Related Art A document image reading apparatus such as a perfect contact type reading method for reading a document image is employed.

FIG. 1 shows a schematic configuration of a conventional document image reading apparatus.
10 is a sectional view schematically showing a conventional document image reading apparatus, and FIG. 11 is a schematic perspective view of FIG.

Here, reference numeral 1 denotes a line sensor as image reading means, which optically reads an image of the document P. Reference numeral 13 denotes an automatic paper feed unit including a combination of a separation piece 11 and a feed roller 12, and separates and feeds the originals P one by one toward the line sensor 1. Reference numeral 2 denotes a conveyance roller as a conveyance unit, which reads the fed document P at a reading position 4 of the line sensor 1.
It has a function of a document transporting means for transporting the document P together with a document contacting means for pressing and contacting the document P.

[0006]

However, according to the knowledge of the present inventors, in the conventional document image reading apparatus, one transport roller has a role as a document transport unit and a role as a document close contact unit. Therefore, there are the following problems.

(1) In order to read a document image by a line sensor, the line sensor and the document need to be brought into close contact with each other. Therefore, the length of the transport roller is equal to the length of the line sensor or the entire reading width of the document. Required. For this reason, the conveyance force varies depending on the position due to the influence of the flatness of the reading surface of the line sensor, which causes the document to be skewed.

(2) When the original is brought into close contact with the reading surface of the line sensor and transported, the load applied to the motor that rotates the transport roller increases, so that the motor is likely to generate heat and lose synchronism. Therefore, a large motor must be used for stable document transport, making it difficult to reduce the size and weight of the document image reading apparatus.

(3) Documents fed obliquely tend to be more oblique. This description will be made with reference to FIG.

FIG. 7 is a schematic plan view of the conventional document image reading apparatus shown in FIGS. 10 and 11 as viewed from above.
It should be noted that the line sensor is disposed on the back side of the document conveying roller 2 in the drawing, not shown.

In FIG. 7A, when the document P is obliquely inserted into the automatic paper feeder 13, the automatic feeder 13 transfers the document P to the transport roller 2 as shown in FIG.
Conveyed by Next, in FIG. 7C, the conveying force (b) of the conveying roller 2 acts on a part of the document P sandwiched between the conveying roller 2 and the line sensor. Generally, the feed roller (not shown) of the automatic feeder 13 has a peripheral speed slightly lower than that of the transport roller 2. Therefore, the load (c) acts in the direction opposite to the document conveying direction due to the peripheral speed difference and the friction piece load, and the rotational force (d) is generated by the forces (b) and (c), and the document P is further inclined. Will do.

As described above, the conventional structure cannot be said to be sufficient for the reduction in size, weight, and price of a document image reading apparatus which has been increasingly spurred in recent years. There are many technical issues.

An object of the present invention is to provide a document image reading device which illuminates a document closely attached to a reading section of a contact type image reading means with a light source, detects light reflected by the document, and reads image information of the document. A document feed roller provided on the document feed side of the reading section, and a document transport provided on the document discharge side of the read section so that the reading section is outside the nip. A roller, a drive transmission unit attached to the document transport roller, for transmitting a driving force for driving the document transport roller from outside the document image reading device, and a drive transmission unit for bringing the document into close contact with the reading unit. And a length of the document feed roller and the document transport roller in a direction perpendicular to the document transport direction is shorter than a length of the document close device. A document image reading device, or a document image reading device that illuminates a document closely attached to a reading unit of a contact type image reading unit with a light source, detects light reflected by the document, and reads image information of the document. In the apparatus, a document feed roller provided on the document feed side from the reading unit, so that the reading unit is outside the nip,
A document transport roller provided on the paper discharge side of the document from the reading unit; and a document feed roller attached to the document transport roller for transmitting a driving force for driving the document transport roller from outside the document image reading apparatus. A drive transmission unit, and a film-shaped original contact unit for bringing the original into close contact with the reading unit, and the original transport roller is provided on the same surface as the reading unit of the image reading unit. This is achieved by a document image reading device that is arranged so as to abut.

It is another object of the present invention to provide a document image reading apparatus which can easily handle a contact type image sensor which is difficult to handle in positioning, document transport, and the like.

Still another object of the present invention is to provide a document image reading apparatus which can be easily attached to and detached from an information processing apparatus.

An object of the present invention is to provide a document image reading apparatus which illuminates a document closely attached to a reading section of image reading means with a light source, detects light reflected by the document, and reads image information of the document. The reading unit is arranged on the document feeding side so as to be outside the nip of the document conveying roller, and a document contact unit for bringing the document into close contact with the reading unit is provided, and a driving force for driving the document conveying roller is provided. The document image reading apparatus is provided with a drive transmission means for transmitting the image data from outside the apparatus.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 6 show a preferred embodiment of the present invention.
In the configuration shown in FIG. 7, when a driving force is applied from the outside 7, the driving force transmitting means for transmitting the driving force is integrally provided. Specific examples thereof will be described later with reference to FIGS. 8, 12, 13, and 14.

FIG. 1 is a schematic sectional view showing a first embodiment of a document image reading apparatus according to the present invention, and FIG.
FIG. 2 is a schematic perspective view of the document image reading device shown in FIG.

1 and 2, reference numeral 1 denotes a line sensor for reading an image of a document P, reference numeral 2 denotes a conveying roller for conveying the document P, and reference numeral 3 denotes a document contact member for bringing the document P into close contact with a reading position 4 of the line sensor 1. It is. Reference numeral 13 denotes an automatic sheet feeding unit including a combination of the separation piece 11 and the feeding roller 12. The document contact member 3 is disposed outside the collapsed width of the transport roller 2 on the document feeder 13 side from a point 5 where the line sensor 1 and the transport roller 2 abut. The distance between the document contact member 3 and the transport roller 2 on the line sensor 1 is determined so that the document contact member 3 and the transport roller 2 arranged at the reading position 4 do not interfere with each other. In general, the automatic paper feeder 1
3 may be unstable due to a change in the paper quality of the document. Therefore, it is desirable that the distance between the document contact member 3 and the transport roller 2 is shorter, and more specifically, the distance that does not cause a problem is 2 to 5 mm. It is.

The transport roller 2 is made of a material such as EPDM (ethylene propylene rubber), CR (chloroprene rubber), and silicon. The original adhesion member 3 is made of PE (polyethylene) PET (polyethylene terephthalate), PE
It is made of a plastic film such as EK (polyetheretherketone), nylon, or fluorine film, or a flexible member such as a metal foil, an aluminum foil, or a titanium foil. Document adhesion member 3
Is desirably 0.1 mm or less. One end of the flexible member 3 is fixed to the support member 6 with an adhesive screw or the like, and the other end abuts on the reading position 4 of the line sensor 1 by its own weight or the spring property of the flexible member itself. 1 reading position.

According to the embodiment of the present invention, the following effects can be obtained.

(1) Since the transport roller 2 has a function of transporting only the original, the rubber portion of the transport roller 2 can be shortened. As a result, the influence of the flatness of the reading surface of the line sensor can be reduced, and stable document conveyance can be performed. Furthermore, since the flatness management of the reading surface of the line sensor, which has been conventionally required, can be reduced, the cost can be easily reduced.

(2) Since the document transport function and the document contact function are configured to be separated by separate members, the pressing force required to transport the document and the pressure required to press the document onto the line sensor are required. The pressing force can be minimized. In other words, what has conventionally required a force sufficient to crush the transport roller 2 and absorb the flatness of the line sensor is no longer necessary. As a result, the load on the motor is reduced, and the outer dimensions and cost of the motor can be reduced.

(3) Even if the sheet is fed obliquely, it is difficult for the sheet to skew. FIGS. 6A to 6C are schematic views of the embodiment of the present invention as viewed from above. It should be noted that the line sensor is disposed on the far side of the document conveying roller 2 in the drawing, not shown. FIG.
When the document P is inserted obliquely in FIG.
As shown in (B), the leading end of the original contact means 3 having no original conveying force hits the original contacting means 3, and a load resistance (e) is generated.
Also, in the automatic sheet feeding section 13, since the sheet feeding force (a) is working, a rotational force (d) for correcting the document P is generated in combination with the load resistance (e), and the document P returns to the normal position. . When the load resistance (e) is distributed over the entire area of the leading edge of the document,
The sheet feeding force (a) overcomes the load resistance (e) and feeds the document to the document feed roller 2. In FIG. 6C, since the document conveying roller 2 has a short roller portion,
Since the rotational force hardly acts between the load (c) and the conveying force (b) of the conveying roller 2, the original can be conveyed without skew. At this time, the center of the rubber portion of the conveyance roller 2 in the main scanning direction, the center of the automatic paper feeding unit 13 and the center of the effective reading length of a line sensor (not shown) are made to coincide with each other, so that the document conveyance which is more difficult to be inclined is performed. Can do it.

(4) By making at least a part of the reading position of the original contacting means 3 white, even when reading a thin paper, a transparent original or a narrow original, the image is not affected. Further, it can be used as a white reference at the time of multi-tone reading. In other words, electrical correction can be performed by storing the output of the line sensor 1 on a bit basis, for example, based on the reflectance of the white portion of the document adhering means 3. As the means for making the document white, the document pressing means 3 itself may be white, or the surface of the document pressing means 3 on the document side may be provided by white painting, printing, or the like. Alternatively, the same effect can be obtained even when the transparent document pressing means 3 is provided on the surface opposite to the document surface by painting or printing.

FIG. 3 is a schematic sectional view showing a second embodiment of the document image reading apparatus according to the present invention. In FIG.
The original contact means is constituted by the elastic member 3 and the pressing spring 7. As the elastic member 3, a material such as rubber or sponge, or a member having shape elasticity is used. In addition,
Although the pressing spring 7 is taken as an example of the pressing means, the effect of using gravity may be obtained.

FIG. 4 is a schematic sectional view showing a third embodiment of the document image reading apparatus according to the present invention. In FIG.
1 shows an embodiment in which a document conveying roller 2 is provided outside a line sensor 1. The backup roller 8 is pressed by the document transport roller 2 to hold and transport the document P in a form following the document transport roller 2. The document pressing means uses a flexible member 3 as in FIG.

FIG. 5 is a schematic sectional view showing a fourth embodiment of the document image reading apparatus according to the present invention. In FIG. 5, a member (hereinafter referred to as a sliding member) 10 having a friction coefficient smaller than a friction coefficient between the reading surface of the line sensor 1 and the conveyance roller 2 at the contact point 5 of the document conveyance roller 2 in the embodiment of FIG.
Has been arranged. Usually, the reading surface of the line sensor 1 is
The sliding member 10 is made of glass, and examples of the sliding member 10 include a fluorine-based resin. The sliding member 10 may be provided on the reading surface of the line sensor 1 by printing, painting, pasting, or the like, or may be provided on, for example, the housing of the line sensor 1 other than the reading surface that does not interfere with paper passing. Thus, even when the document P is not at the contact point 5 of the transport roller 2, the transport roller 2 can be driven to rotate with a light load, which is effective for reducing the size and power consumption of the motor.

Although not shown, the driving force transmitting means of the first to fourth embodiments described above is constituted by a plurality of gears, timing belts and the like.

FIGS. 8 and 9 show a document image reading apparatus according to a fifth embodiment of the present invention which is best characterized by the features of the present invention. This is an example. The separation piece 11 is supported by a member (not shown) and is locked on the frame 9.
The frame 9 has a structure in which the line sensor 1, the separation piece 11, the paper feed roller 12, the document transport roller 2, and the document contact means 3 are integrally supported.

The paper feed roller 12 and the original conveying roller 2 are provided as a driving force transmitting means for transmitting a driving force from a driving source provided in an apparatus main body (for example, an entire configuration including communication means of a facsimile apparatus). It is driven and rotated by two gears 14.

FIG. 12 is a schematic diagram showing a state in which the unit shown in FIG. 8 is mounted on the apparatus main body. Unit 1
00 is mounted by moving along guides 59 and 62 parallel to the direction of arrow AA. The longer guide 59 has a stopper at the end, and the shorter guide 62 has a connector 60 also serving as a stopper at the end. The connector 60 is configured to be electrically connectable to the signal terminal 63 on the unit 100 side. The signal terminal 63 includes a line for transmitting a drive signal of the line sensor 1, an image signal from the line sensor 1, a reference signal, and the like. The signal terminal 63 is electrically connected to the main body via the wiring 61 by contact with the connector 60 and mutually controlled. It becomes possible.

A motor 57 as a drive source is fixed to the side wall of the body-side frame 58 to which these members 59 to 62 are fixed. This motor 57 has a gear 56
The gear 51 is attached when the unit 100 is mounted.
The driving force is transmitted to the unit side gear 14 via the gear 51. The rollers 2 and 12 are rotated by the transmitted driving force. The gear 51 is rotatably attached to an arm 52 that rotates about a shaft 55 fixed to a side wall, and is swingable with respect to the shaft 55 as indicated by an arrow BB. When the unit 100 is not mounted, the arm 52 is urged downward by the spring 54. A stopper 53 is provided below to restrict the rotation of the arm 52 (FIG. 12).

Next, FIG. 13 shows a state in which the unit 100 is completely mounted on the main body frame 58.

As the unit moves in the direction of arrow AA (FIG. 12), the gear 14-1 of the transmission gear 14 provided on the shaft of the paper feed roller 12 comes into contact with the gear 51. The gear 51 is pushed upward by the gear 14-1 against the urging force CC, and abuts on the gear 56 of the driving source.

When the unit 100 is further moved, the movement is restricted by the stoppers 59 and 60, and at the same time, the electrical connection by the connector 60 is completed. At this time gear 14
-1, 51 and 56 are completely engaged (FIG. 1
3).

FIG. 14 is a schematic diagram for explaining a facsimile apparatus having the original image reading apparatus of the present invention.

When the document P is mounted on the document image reading apparatus 100 and the transmission operation starts, the driving source 93
The transport rollers inside rotate the original, and the image information is read by the line sensor. This information is stored in a memory in the control means 90 as an electric signal.

When the communication means 91 connects to the external line 94 connected to the transmission destination, the image signal in the memory is transmitted through the communication means.

The recording means 92 records the transmitted image signal on a recording medium, and includes a thermal head and an ink jet recording head.

[0042]

As described above, the original image reading apparatus according to the present invention solves the problems of the prior art, such as skew, high cost, and large external dimensions of the motor and the like. , Lighter weight, and lower price have become possible. Further, the following advantages can be obtained by integrally disposing the embodiment of the present invention on the frame and unitizing it.

(1) The accuracy of assembling components related to document reading is improved.

(2) By standardizing this unit and incorporating it in common with each model of the image information processing apparatus, the design,
The load of evaluation and production can be greatly reduced, and the total cost of the image information processing apparatus can be reduced.

(3) Since the document image reading device is a small and lightweight unit image reading device, the layout in the image information processing device is facilitated, and the design and design flexibility are improved.

(4) When the original reading device in the image information processing apparatus is defective or broken down, the repair can be performed only by replacing the unit, so that the user himself can easily do so without any special education, skills and tools. Can be repaired.

According to the present invention, an inexpensive and small-sized original image reading apparatus can be provided, and can be applied to various image information processing apparatuses such as a facsimile, an image sensor, a computer, a word processor, and a copying machine.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing a first embodiment of a document image reading apparatus according to the present invention.

FIG. 2 is a perspective view schematically showing a first embodiment of a document image reading apparatus according to the present invention.

FIG. 3 is a sectional view schematically showing a second embodiment of the document image reading apparatus according to the present invention.

FIG. 4 is a sectional view schematically showing a third embodiment of the document image reading apparatus according to the present invention.

FIG. 5 is a sectional view schematically showing a fourth embodiment of a document image reading apparatus according to the present invention.

FIG. 6 is a diagram illustrating a state of transporting a document in the document image reading apparatus according to the present invention.

FIG. 7 is a diagram illustrating a state of transporting a document in a conventional document image reading apparatus.

FIG. 8 is a perspective view schematically showing a fifth embodiment of a document image reading apparatus according to the present invention.

FIG. 9 is a sectional view schematically showing a fifth embodiment of the document image reading apparatus according to the present invention.

FIG. 10 is a cross-sectional view schematically showing a conventional document image reading apparatus.

FIG. 11 is a perspective view schematically showing a conventional document image reading apparatus.

FIG. 12 is a schematic diagram for explaining the mounting operation of the image reading apparatus to the apparatus main body according to the present invention.

FIG. 13 is a schematic view for explaining an operation of mounting the image reading apparatus to the apparatus main body according to the present invention.

FIG. 14 is a block diagram showing a control system of the image reading apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Line sensor 2 Document conveyance roller 3 Document contact means 4 Reading position 5 Contact position of document conveyance roller 6 Support member 7 Press spring 8 Backup roller 9 Frame 10 Sliding member 11 Separation piece 12 Paper feed roller 13 Automatic paper feed section 14 Gear P Document (a) Document feed force of automatic feeder (b) Document feed force of feed roller (c) Load of automatic feeder (d) Rotational force (e) Load

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tetsuya Shimada 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-2-238765 (JP, A) JP-A Sho-62 254563 (JP, A) JP-A-2-13064 (JP, A) Japanese Utility Model Application Sho 58-8264 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 1/00 H04N 1/04-1/207 B65H 9/00-9/20 B65H 5/06

Claims (9)

(57) [Claims] 1. A document image reading apparatus for illuminating a document closely attached to a reading section of a contact type image reading means with a light source, detecting light reflected by the document, and reading image information of the document, A document feed roller provided on a document feeding side of the document from a reading unit; a document transport roller provided on a document discharge side of the document from the reading unit so that the reading unit is outside the nip; A drive transmission means attached to the document transport roller for transmitting a driving force for driving the document transport roller from outside the document image reading device; and a film-shaped document for bringing the document into close contact with the reading unit. A document, wherein the length of the document feed roller and the document transport roller in a direction perpendicular to the document transport direction is shorter than the length of the document contact device. Image reading device. 2. The document image reading apparatus according to claim 1, wherein said film-shaped document contact means has a white color. 3. The document feeder according to claim 1, wherein the document feed roller, the image reading means, the document feed roller, and the document contacting means are integrally arranged on a frame to form a unit. Document reading device according to the above. 4. A document image reading apparatus which illuminates a document closely attached to a reading section of a contact type image reading means with a light source, detects light reflected by the document, and reads image information of the document. A document feed roller provided on a document feed side of the document from a reading unit, and a document feed roller provided on a document discharge side of the document from the read unit so that the read unit is outside the nip. A drive transmission unit attached to the document transport roller for transmitting a driving force for driving the document transport roller from outside the document image reading device; and a film-shaped unit for bringing the document into close contact with the reading unit. A document adhering unit, wherein the document transport roller is disposed on the same surface as the reading unit of the image reading unit so as to contact the surface. 5. A straight line connecting a center position of a document feed roller in a direction perpendicular to the document transport direction and a center position of the document transport roller in a direction perpendicular to the document transport direction is a main scan of the image reading means. 5. The document image reading device according to claim 4, wherein the document image reading device passes through the center of the effective reading unit in the direction. 6. The document according to claim 4, wherein a slip member having a smaller coefficient of friction with respect to the document conveying roller than a coefficient of friction of the surface with respect to the document conveying roller is provided at a position where the document conveying roller abuts. Image reading device. 7. The document image reading apparatus according to claim 4, wherein said film-shaped document contact means has a white color. 8. The document feeder according to claim 4, wherein said document feed roller, said image reading means, said document feed roller and said document contact means are integrally arranged on a frame to form a unit. The document image reading device according to any one of the preceding claims. 9. The document image reading device according to claim 1, wherein the document reading device is detachably mounted on an information processing device having a drive source that generates the driving force.