JPH11292301A - Automatic document feeder - Google Patents

Abstract

[PROBLEMS] To provide an automatic document feeder excellent in durability, capable of realizing stable transport quality, easy to assemble and low in cost, and suitable for downsizing. A part of a document positioning surface of a side fence (1a) is formed of a metal wear-resistant member. Further, the wear-resistant member and the side fence moving means (rack 36) are integrally formed, and a wall of the rack 36 is a part of the document positioning surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder mounted on a copying machine or the like, and more particularly to a circulation type automatic document feeder.

[0002]

2. Description of the Related Art In a general automatic document feeder, documents stacked on a document table are separated one by one and conveyed onto a contact glass, and a desired number of copies are copied at a reading position on the contact glass. Then, the document is discharged to a discharge tray. Therefore, only one pass is required regardless of the number of copies, and the durability of the apparatus is about 600,000. On the other hand, in a circulation type automatic document feeder that circulates the separated documents according to the number of copies, it is necessary to increase the durability of the device. It is. In such a device,
The side fence for positioning in the document width direction is a component that is always touched by the user, and is often made of resin from the viewpoint of safety in consideration of electric shock due to charging and discharging.

[0003] It should be noted that related devices of this type include, for example, Japanese Patent Application Laid-Open Nos.
No. 166139.

[0004]

In the prior art, the positioning surface of the side fence in the document width direction is severely worn, and in reality, the positioning accuracy in the document width direction is reduced to about one million sheets, and the document skew is reduced. And other problems occur. SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic document feeder that can solve such problems, has excellent durability, and can realize stable transport quality. More specifically, the wear of the document positioning surface due to the document passing is reduced, the position of the document on the document table is prevented from shifting, the occurrence of skew and the like can be suppressed, and the document is circulated on the transport path. It is an object of the present invention to allow a returned document to smoothly fall on a document table. Another object of the present invention is to provide an automatic document feeder which is easy to assemble, is low in cost, and is suitable for downsizing.

[0005]

In order to achieve the above object, an automatic document feeder according to the present invention is an automatic document feeder which feeds, separates and transports originals stacked on an original table one by one. A side fence for positioning a document stacked on the document table in a document width direction, and a document positioning surface of the side fence is formed of a wear-resistant member different from other members forming the side fence. It is characterized by having been done.

In order to achieve the above object, an automatic document feeder according to the present invention is mounted on a copying machine and feeds and separates the documents stacked on a document table one by one. The circulating automatic document feeder has at least one pair of side fences for positioning a document stacked on the document table in a document width direction, and a part of the document positioning surface of the side fence is made of metal. It is characterized by being formed from a wear-resistant member made of.

Further, a part of the document positioning surface formed by the wear-resistant member is formed in a concave shape. Further, there is provided a side fence moving means for changing a distance between the pair of side fences in accordance with the size of the document in the width direction, wherein the wear-resistant member is integrally formed with the moving means. And

[0008]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of an automatic document feeder according to an embodiment of the present invention, FIG. 2 is a perspective view showing a configuration of a side fence in the automatic document feeder of FIG.
FIG. 3 is a cross-sectional view of the side fence of FIG. 2 (FIG. 2B is
FIG. 2A is an enlarged view of FIG. 2A, and FIG. 4 is a view showing a method of assembling the side fence of FIG. The automatic document feeder according to the present embodiment is mounted on a copying machine main body (not shown), and feeds a document 4 stacked on a document table 3 in a document setting section 23 to a feed belt 6 and a pull-out roller 7. The paper is fed and separated one by one, and is circulated according to the number of copies. In addition, the document setting unit 23 includes
As shown in FIG. 2, at least one pair of side fences 1 (side fences 1a and 1b) for positioning the documents 4 stacked on the document table 3 in the document width direction.
And an end fence 2 for positioning the rear end of the document. As shown in FIGS. 3A and 4, the side fence 1 a has a part of the document positioning surface of the side fence 1 (a metal wall 39 formed on the rack 36 is a square window 46 of the side fence 1 a). Is formed from a metal wear-resistant member. In addition, side fence 1
The other part of a is made of a member made of resin or the like.
The rack 36 (= side fence moving means) is shown in FIG.
The pair of side fences 1 via the gear 36a as shown in FIG.
The gap between them is changed in accordance with the size of the document in the width direction by sliding and moving a and 1b. The wall 39 is formed integrally with the rack 36 as shown in FIGS. ing. When assembling these parts 36 and 39, as shown in FIG. 4, the wall 39 is inserted into a through hole 40 having a rectangular cross section provided in the side fence 1a, and the rack 3 is inserted.
6 is set on the side fence 1 a and fixed with screws 37. According to the present embodiment, since the rack 36 and the side fence 1a are integrally configured, it is easy to assemble, low in cost, and contributes to downsizing of the apparatus. The side fence 1a has a rectangular window 4 on the surface 38 for determining the position in the document width direction.
6 are provided, and as shown in FIG.
On the other hand, the wall 39 of the rack 36 is recessed by a depth x (specifically, 1 mm or less) with respect to the window 46 and is formed in a concave shape. That is, there is a step of 1 mm or less between the document positioning surface formed by the wall 39 and the surface 38. In addition to the present embodiment, a separate rectangular part having a size equivalent to the window 46 made of a metal wear-resistant member is attached without providing the window 46 on the surface 38 and without being integrated with the rack 36. Or it may be attached. In this case, when the document 4 returning to the document table 3 by circulating through the transport path in the apparatus falls, the document 4 is formed to be thinner so as not to be caught by the separate component. In the present embodiment, the side fence 1a has been described, but the side fence 1b paired with the side fence 1a is similarly configured.

The paper feeding belt 6 in the document setting section 23 is formed by forming a plurality of endless belts in parallel with the paper feeding direction as shown in FIG. In this case, a suction hole (not shown) for sucking the lowermost document 4 is arranged. This suction hole is provided in the vacuum tank 25 below the paper feeding belt 6, and a valve (not shown) in the vacuum tank 25 is provided.
It is configured to open and close. The opening and closing of the valve is performed by turning on / off a solenoid (not shown). On the other hand, an air knife 5 is provided above the paper feed side end of the paper feed belt 6, and is compressed from a plurality of nozzles 24 of the air knife 5 to the paper feed side end of the stacked originals 4 by an ADF blower motor (not shown). By blowing air, double feed during document feeding is prevented, and sheets are separated one by one.

As shown in FIG. 5, a SADF paper feeder according to the present embodiment includes a SADF document table 19 for setting a document so that an image surface faces upward. Side fence 45 for positioning, SADF partitioning claw 30 driven by a solenoid not shown, relay lever 34 for relaying the operation of SADF partitioning claw 30 to link SADF pressure roller 35, solenoid not shown , A SADF roller 18 driven by a drive motor (not shown), and a drive motor (not shown), and set on the document table 3 in conjunction with the operation of the SADF partitioning claw 30. And a SADF pressure roller 35 that pressurizes and feeds the original. The side fence 45 is smaller than the side fence 1 and is made of, for example, resin.

The documents 4 separated one by one in the document setting section 23 are conveyed onto a contact glass 9 through respective conveying paths, and the contact glass 9 is together with a slit glass (not shown). This is provided on the upper surface of the copying machine. An exposure lamp, a first mirror, and the like (not shown) are provided below the contact glass 9 and the slit glass. The exposure lamp and the first mirror move in the horizontal direction in FIG. 1 when reading the original 4 on the contact glass 9, and stop below the slit glass when reading the original 4 on the slit glass. Then, light is irradiated on the image surface of the original by the exposure lamp. After the exposure process is completed, the reflected light is imaged on a photosensitive drum (not shown) via a first mirror and an optical system (not shown), and the electrostatic light formed on the photosensitive drum is formed. The image forming apparatus is configured to attach toner or the like to the latent image and transfer the toner image to recording paper. Alternatively, an image of the reflected light is formed on an image sensor (not shown) such as a CCD via the optical system, and a recording sheet is formed by image forming means (not shown) using a signal photoelectrically converted by the image sensor. Is configured to transfer an image.

Next, the operation of the automatic document feeder of this embodiment will be described. First, the case of the RDH single-sided original and single-sided copy mode will be described. In the present embodiment, the document 4 is set on the document table 3 of the document setting unit 23 so that the image surface faces upward. At this time, the end fence 2 and the side fence 1 (side fence 1a,
According to 1b), the positioning of the rear end of the document and the width direction is performed.
According to the present embodiment, as described above, a part (wall 39) of the document positioning surface of the side fence 1 is formed of a wear-resistant member made of metal. It can be performed. In addition, since only a part of the document positioning surface, not the entire side fence 1, is made of metal, the user does not receive an electric shock due to charging or discharging, and can be used safely. After the original 4 is set at a predetermined position, the copy start key of the operation unit (not shown) of the copying machine is pressed, whereby the partition plate 15 built in the end fence 2 is driven to rotate, and Touch the top. At the same time, a fan motor (not shown) rotates, and a plurality of nozzles 2 provided below the air knife 5 are provided.
4, compressed air is blown from the leading end of the stacked originals 4 on the paper feed side, and the originals 4 are in a floating state. At this time, a valve (not shown) in the vacuum tank 25 is turned on.
Thus, when a suction force is applied, only the lowermost document is sucked through the plurality of holes on the upper surface of the paper feeding belt 6, and the document 4 other than the lowermost document is maintained in a floating state. When the paper feed belt 6 is rotated counterclockwise in this state, only the lowermost document is pulled out.

When the IN sensor 26 detects that the leading edge of the lowermost document has been nipped by the pull-out roller 7, the driving of the paper feed belt 6 is stopped, and the valve in the vacuum tank 25 is turned off. By interrupting the suction force, the conveyance force is not applied to the next original. The document nipped by the pull-out roller 7 is fed to a sheet feeding deflection claw 8 driven by a solenoid (not shown).
The direction is changed to the direction of the contact glass 9 (direction A), and the paper is conveyed onto the contact glass 9 by the paper feed roller 10 and the conveyance belt 11. The pull-out roller 7, the sheet feeding roller 10, and a reversing roller 17, which will be described later,
The ADF rollers 18 are driven at the same speed by the same drive motor (not shown). After the exposure on the contact glass 9 is completed, the original is conveyed by a conveyor belt 11 and a pair of paper discharge rollers 12, and RDH is discharged by a discharge deflection claw 13.
The direction is changed in the direction of the document table 3 (direction D), and the document is returned to the RDH document table 3 by the discharge belt 14. In addition,
The division of the job is made by the partition plate 15 in the end fence 2. According to the present embodiment, as described above, a part (wall 39) of the document positioning surface of the side fence 1 is formed in a concave shape using a metal wear-resistant member. The original positioning surface can be constantly positioned with little wear on the original positioning surface, and the original 4 circulating on the transport path and returning can fall on the original table 3 by touching the corners of the wall 39 to improve alignment. No disturbing.

Next, the case of the RDH double-sided original and double-sided copy mode will be described. As in the single-sided copying mode, the original conveyed by the pull-out roller 7 is turned in the reversing direction (B direction) by the feeding deflecting claw 8 and the reversing deflecting claw 16 interlocked therewith, and conveyed by the reversing roller 17 and the SADF roller 18. Then, the sheet is further conveyed in the direction of the reverse conveying path 32 by the SADF deflection claw 31 shown in FIG. The SADF deflection claw 31 is driven by a solenoid (not shown). Further, the SADF deflection claw 31 switches at the same time as receiving the signal indicating the double-sided copying mode from the copying machine main body operation unit, and does not perform the switching operation until one job divided by the partition plate 15 is completed. Also, SADF
The pressure roller 35 is driven by a solenoid (not shown) in conjunction with a SADF partitioning claw 30 described later.
At the same time as the operation of the ADF switching claw 31, the pressure is switched to the pressurized state. Thereafter, when the reversing sensor 20 detects the passage of the rear end of the document, the drive motor rotates in the reverse direction to perform a switchback operation. At the same time, the sheet feeding deflection claw 8 and the reverse deflection claw 1
6 can be turned each other, so that the switched back document turns in the direction of the contact glass 9 (direction C).
The sheet is conveyed in an inverted state on the contact glass 9 by the sheet feeding roller 10 and the conveying belt 11. Then, after the exposure of the image side (back side) of the reversed document is completed, the document is returned to the RDH document table 3 as in the one-sided copy mode. At this time, since the front and back sides are reversed from the state where the original was set, the switchback operation is performed simultaneously with the completion of the exposure of the back side of all the set originals. The document is copied and returned to the RDH document table 3 in the state of being set first. According to the present embodiment, as described above, a part (wall 39) of the document positioning surface of the side fence 1 is formed in a concave shape using a metal wear-resistant member. The original positioning surface can be always stably positioned with little wear on the original positioning surface, and the original 4 circulated on the transport path and returned.
However, when dropping onto the document table 3, the corners of the wall 39 do not touch and cause skew.

Next, the SADF mode will be described.
The document 4 is set on the SADF document table 19 with the image surface facing upward and the front end abutting against the SADF partitioning claw 30. The SADF partitioning claw 30 is in a partitioning state in a default state, and the SADF pressure roller 35 interlocked with the operation of the SADF partitioning claw 30 via the relay lever 34 is
It is in a non-pressurized state. The SADF partitioning claw 30 is opened by the copy start signal from the operation unit of the copier main body, and the SADF pressure roller 35 is lowered to press the document 4 and, at the same time, the drive motor (not shown) is driven to drive the document. Reference numeral 4 denotes the SADF roller 18 and the reversing roller 1 similarly to the operation after the switchback in the reversing mode.
7 and is turned in the direction (C direction) of the contact glass 9 by the sheet feeding deflection claw 8 and the reversing deflection claw 16,
The paper is conveyed onto the contact glass 9 by the paper feed roller 10. Further, after the exposure is completed, the original 4 is conveyed by the conveyance belt 11 and the paper discharge roller 12,
Change the direction to ADF paper discharge table 21 direction (E direction),
The paper is discharged onto the SADF paper discharge table 21 by the paper discharge rollers 22.

In this embodiment, the circulation type automatic document feeder has been described. However, the configuration of the side fences 1, 1a, 1b can be naturally applied to a non-circulation type automatic document feeder. In addition, similarly, the durability of the document positioning surface can be enhanced, and stable conveyance quality can be realized.

[0017]

As described above, according to the present invention,
Since the document positioning surface of the side fence for positioning in the document width direction on the document table of the automatic document feeder is formed of a wear-resistant member different from other members, the durability of the document positioning surface can be enhanced. More specifically, since a part of the document positioning surface is formed from a wear-resistant member made of metal, the document positioning surface is excellent in durability and can realize stable conveyance quality. That is, since the abrasion of the document positioning surface due to the document passing is reduced, the position of the document on the document table is prevented from shifting, the occurrence of skew and the like is suppressed, and the stable transport quality can be always realized. .

Further, according to the present invention, since a part of the document positioning surface is formed in a concave shape, the document circulating on the transport path and returning can be smoothly transferred without being caught by the wear-resistant member. Can fall on the table. Therefore, it is possible to suppress the disorder of the alignment of the stacked originals and the occurrence of the folding of the originals. According to the present invention,
Since the abrasion-resistant member that forms a part of the document positioning surface of the side fence and the side fence moving means are integrally formed, assembly is easy, low cost, and suitable for downsizing the apparatus.

[Brief description of the drawings]

FIG. 1 is a sectional view of an automatic document feeder according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a side fence in the automatic document feeder of FIG. 1;

FIG. 3 is a sectional view of the side fence of FIG. 2;

FIG. 4 is a view showing a method of assembling the side fence of FIG. 2;

FIG. 5 is a cross-sectional view of the SADF paper feeding unit of FIG.

[Explanation of symbols]

 1, 1a, 1b Side fence 2 End fence 3 Document table 4 Document 6 Paper feed belt 36 Rack 37 Screw 38 Positioning surface 39 Wall 40 Through hole 46 Window

Claims (4)

[Claims] An automatic document feeder that feeds, separates, and conveys the originals stacked on the original table one by one for positioning the originals stacked on the original table in the width direction of the original. An automatic document feeder having a side fence, wherein a document positioning surface of the side fence is formed of a wear-resistant member different from other members forming the side fence. 2. An automatic document feeder that is mounted on a copying machine, feeds and separates documents stacked on a document table one by one, and circulates according to the number of copies. An automatic manuscript having at least one pair of side fences for positioning the manuscript in the manuscript width direction, wherein a part of the manuscript positioning surface of the side fence is formed of a metal wear-resistant member; Transport device. 3. The automatic document feeder according to claim 2, wherein a part of the document positioning surface formed by the wear-resistant member is formed in a concave shape. 4. A side fence moving means for changing a distance between the pair of side fences according to a size of the document in the width direction, wherein the wear-resistant member is formed integrally with the moving means. 4. The automatic document feeder according to claim 3, wherein: