JP2007168947A - Automatic document carrying device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an automatic document carrying device and image forming device, capable of preventing abnormalities of each device provided within an automatic document placement part by preventing static electricity caused by electric charges charged on documents, and having simple structures. <P>SOLUTION: This automatic document carrying device is provided with a paper feed member 7 for feeding a bundle P of documents placed on a document table 5 from the uppermost face of the document bundle P sequentially one by one; a butting plate 25 for regulating the movement of the document bundle P placed on the document table 5 from the document table 5; and a document carrying path 32 for carrying documents fed by the paper feed member 7 to the paper delivery direction. The butting plate 25 is movable between a shut-off position for shutting off the document carrying path 32 and an opening position for opening the document carrying path 32, and is provided with a static eliminating brush 40 for eliminating electric charges charged on documents. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an automatic document feeder and an image forming apparatus.

  In the prior art described in Patent Document 1, in the automatic document feeder, a charge eliminating member is provided between a document feed tray (document placement table) and a sheet discharge tray to contact the document discharged to the sheet discharge tray. Thus, there is disclosed a technique for neutralizing a document.

JP 2005-75493 A

  However, in the prior art described in Patent Document 1, since a static elimination member is provided between the lower portion of the document placement table and the paper discharge tray, an attachment member for the neutralization member is additionally required at the lower portion of the document placement table. There was a problem that the configuration was complicated. In the above-described conventional technology, the document discharged to the discharge tray is neutralized. However, the document is fed between the time when the document is fed from the mounting table and the document is discharged to the discharge tray. There was a possibility that static electricity was generated by the charged electric charge. In this case, there is a possibility that an abnormality of each device such as a detection sensor or an electrical component provided in the automatic document placement may occur due to the generated static electricity.

  The present invention provides an automatic document feeder and an image forming apparatus that can prevent the occurrence of static electricity due to electric charges charged on a document, prevent the occurrence of abnormality in each device provided in the automatic document stacking, and have a simple configuration. With the goal.

  In order to solve the above problems, the invention described in claim 1 is directed to a paper feed member that feeds a bundle of documents placed on the document placement table one by one from the top surface one by one, and a document placement table. A restriction member that restricts movement of the placed document bundle from the document placement table, and a document conveyance path that conveys the document fed by the sheet feeding member in the paper discharge direction. It is possible to move between a blocking position for blocking and an open position for opening the document conveyance path, and the regulating member is provided with a charge eliminating member for removing charges charged on the document.

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, the charge eliminating member is a charge eliminating brush.

  According to a third aspect of the present invention, in the second aspect of the present invention, the automatic document feeder includes a main body frame, and the neutralization brush contacts the main body frame, and the charge removed by the neutralization brush is passed through the main body frame. It is characterized by discharging outside.

  The invention described in claim 4 is characterized in that, in the invention described in claim 2 or 3, when the restricting member is in the open position, the brush bristles of the static eliminating brush protrude in the document transport path. To do.

  The invention described in claim 5 is the invention described in claim 2 or 3, further comprising a restriction member movement control means for controlling movement of the restriction member, and when the restriction member is in the open position, the restriction member is a bristle. Can be moved between a protruding position where the brush protrudes in the document conveying path and a retracted position where the brush bristles are retracted from the document conveying path. The restriction member is moved between the two.

  According to a sixth aspect of the present invention, in the fifth aspect of the invention, a document leading edge detection sensor for detecting the leading edge of the document is provided on the document conveying path, and the regulation is performed when the leading edge detection sensor does not detect the leading edge of the document. The restricting member is retracted to the retracted position by the member movement control means, and when the leading edge detection sensor detects the leading edge of the document, the restricting member movement control means moves the restricting member from the retracted position to the protruding position. And

  According to a seventh aspect of the present invention, in the image forming apparatus including the automatic document feeder according to any one of the first to sixth aspects, an image is formed by reading a document conveyed by the automatic document feeder. It is characterized by that.

According to the present invention, since the neutralizing member is provided on the regulating member that regulates the movement of the document bundle from the document placement table, the document bundle placed on the document placement table and the document fed into the transport path are provided. The charged electric charge can be removed, and static electricity hardly occurs due to the electric charge charged on the original conveyed in the conveying path. Accordingly, it is possible to prevent the occurrence of an abnormality in each device (electrical component or detection sensor) provided in the automatic document placement. Since the neutralizing member is provided on the regulating member, a separate mounting member for the neutralizing member is not required, and the configuration is simple.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a sectional view showing a driving mechanism for a butting plate according to the first embodiment, FIG. 2 is a perspective view showing the driving mechanism for the butting plate according to the first embodiment, and FIG. 3 is a driving mechanism for the calling roller. FIG. 4 is a sectional view schematically showing the automatic document feeder according to the first embodiment of the present invention, and FIG. 5 is provided with the automatic document feeder according to the first embodiment of the present invention. 2 is a cross-sectional view showing the image forming apparatus.

  As shown in FIG. 5, the image forming apparatus 1 is a copying machine and includes an apparatus main body 1a and an automatic document feeder (hereinafter simply referred to as ADF) 4 provided on the upper part of the apparatus main body 1a. A contact glass 2 and a slit glass 3 having a smaller area than the contact glass 2 are provided on the upper surface of the apparatus main body 1a. The apparatus main body 1a includes a scanner 31, a writing unit 200 that writes image data read by the scanner 31 onto a photosensitive drum, an image forming unit 201, a fixing unit 208, a paper feeding unit 206, and the like.

  Image information of a document read by the scanner 31 is output as image data to a main body control unit (not shown), and the main body control unit is placed on the photosensitive drum 202 constituting the image forming unit 201 by the writing unit 200. An electrostatic latent image is formed, and a visible image of toner is formed on the photosensitive drum 202 by the cooperation of the charging unit 203, the exposure unit 204, and the developing unit 205 constituting the image forming unit 201. .

On the other hand, the transfer paper fed from the paper feeding unit 206 is conveyed to the image forming unit 201, and toner is transferred to one surface of the transfer paper by the transfer unit 207 constituting the image forming unit 201, and the fixing unit. The transfer sheet on which fixing by 208 is completed is conveyed to the reverse discharge unit 209.
Here, the I path in the reverse paper discharge unit 209 is a straight paper discharge path for the transfer paper to the outside of the image forming apparatus 1, and the II path is a path through which the transfer paper is reversed and discharged in the reverse paper unit 209. , III path after the transfer paper is reversed in the reverse discharge unit 209, after the transfer paper is re-fed to the double-sided tray, the other side of the transfer paper is transferred through the image forming process described above, It is discharged out of the image forming apparatus 1 through the I path.

  As shown in FIG. 4, the ADF 4 is provided with a document table (document placement table) 5 on the upper surface, and the document table 5 is a document composed of a plurality of documents on the back side reference (downstream reference in the document transport direction). The bundle P can be set. A document detection sensor 6 including an optical sensor or the like is provided on the back side of the document table 5. The document detection sensor 6 detects a document set on the document table 5 and outputs detection information to a controller (not shown). It is supposed to be. The controller outputs a paper feed start signal based on the detection information from the sensor 6.

  A calling roller (paper feeding member) 7 is provided at the front end of the document table 5 (downstream in the document conveyance direction). The calling roller 7 is separated from the contact position and the document bundle P where the document roller P contacts. It swings between the separated positions.

  As shown in FIG. 3, the calling roller 7 has a rotating shaft 7 a rotatably supported on a bracket 8, and the bracket 8 is fixed to a supporting shaft 9. A lever 10 is fixed to the support shaft 9, and a first protrusion 10 a is formed at one end of the lever 10 in the extending direction. The first protrusion 10 a is a tongue 8 a formed on the bracket 8. Can be engaged.

  A second protrusion 10 b is formed at the other end in the extending direction of the lever 10, and the second protrusion 10 b is in sliding contact with the cam 11. The cam 11 is connected to a link 12, and one end of the link 12 is urged toward the main body 1a by a first spring (connecting member) 13a. The other end of the link 12 is connected to the solenoid 14 via a second spring (connecting member) 13b.

  The solenoid 14 is driven on the basis of an output signal from the controller. When the solenoid 14 is in the ON state, the second spring 13b is pulled against the urging force of the first spring 13a so that the link 12 in FIG. By rotating in the rotation direction, the cam 11 is rotated to lower the second protruding portion 10b, and the calling roller 7 is brought into contact with the document bundle P. In the OFF state, the link 12 is rotated counterclockwise in FIG. 2 by the first spring 13a, thereby rotating the cam 11 to raise the second projecting portion 10b to bring the calling roller 7 into the original bundle. It is designed to be separated from P. That is, the solenoid 14 moves the calling roller 7 between the contact position and the separation position.

  On the other hand, a paper feeding belt 15 is provided on the downstream side in the document conveying direction with respect to the calling roller 7, and this paper feeding belt 15 is bridged by a driving roller 15a and a driven roller 15b, and is rotated clockwise by the driving roller 15a. It is designed to move around. A reverse roller 16 is slidably contacted with the paper feed belt 15 and the reverse roller 16 rotates in a clockwise direction that is a separation direction. Therefore, the uppermost document is separated from the document bundle P conveyed between the paper feed belt 15 and the reverse roller 16.

  The separated original is conveyed to the slit glass 3 via the pull-out driving roller 17 and the pull-out driven roller 18, and the original is detected by a registration sensor 19 a located on the downstream side of the pull-out driving roller 17 and the pull-out driven roller 18. When the leading edge is detected, the controller reverses the sheet feeding motor that drives the calling roller 7, the driving roller 15a, and the pull-out driving roller 17.

  Although not shown, the driving force of the sheet feeding motor is transmitted to the calling roller 7, the driving roller 15a, and the pull-out driving roller 17 through a transmission mechanism including a plurality of gears and a timing belt. Is driven forward, the calling roller 7, the driving roller 15a and the pull-out driving roller 17 are rotated in the document separating direction via the transmission mechanism, and when the paper feeding motor is driven in reverse, the transmission is transmitted via the one-way clutch. Since the driving roller 15a connected to the mechanism is idle, the sheet feeding belt 15 is prevented from idling to separate the next original from the original bundle.

  The document that has been read by the slit glass 3 is nipped between the transport driving roller 20 and the transport driven roller 21 and transported, and then the paper discharge drive roller (paper discharge roller) 22 and the paper discharge driven roller (paper discharge roller) 23. The paper is discharged onto a paper discharge tray 24 sandwiched between the two. The transport drive roller 20 and the paper discharge drive roller 22 are rotated by a paper discharge motor (motor) and a speed reduction mechanism (not shown).

  A paper discharge sensor 19b is provided in the vicinity of the paper discharge driving roller 22, and this paper discharge sensor 19b detects the trailing edge of the original and outputs the original paper discharge information to the controller. On the other hand, an abutting plate (regulating member) 25 that is an abutting plate is provided at the leading end of the document table 5, and the leading end of the document bundle P set on the document table 5 abuts against the abutting plate 25. It is supposed to be.

  The abutting plate 25 is formed in an L shape and is fixed to the support shaft 26. A link 27 is attached to the end of the support shaft 26, and one end of the link 27 is urged toward the main body 1a by a first spring 28a. The other end of the link 27 is connected to the solenoid 14 via the second spring 28b. Further, a neutralizing brush (static eliminating member) 40 is attached to the L-shaped portion of the abutting plate 25.

  When the solenoid 14 is on, the second spring 28b is pulled against the bias of the first spring 28a to rotate the link 27 in the counterclockwise direction in FIG. The transport path 32 is retracted to an open position where the transport path 32 is opened. When the solenoid 14 is OFF, the link 27 is rotated in the clockwise direction in FIG. 1 by the first spring 28 a, so that the abutting plate 25 blocks the transfer path 32 from the retracted position so that the transfer path 32. Protrusively inside.

  When the abutting plate 25 is in the open position, as shown in FIG. 1, the brush bristles 40a of the static elimination brush 40 are positioned above the paper feed guide plate 32a (projected in the conveyance path 32), and are conveyed. The bristles 40a are in contact with the surface of S.

  Further, the automatic document feeder 1 is provided with a metal main body frame 42, and when the abutting plate 25 is in the open position, the charge removed by the static eliminating brush 40 when the neutralizing brush 40 comes into contact with the main body frame 42 is removed. 42 is discharged outside the automatic document feeder 1.

  A plate-like member 29 is provided at the end of the support shaft 26, and a cam 30 is in sliding contact with the plate-like member 29. The cam 30 is attached to the end of the rotation shaft 22 a of the paper discharge drive roller 22, and rotates with the rotation of the paper discharge drive roller 22. The cam 30 is connected to the rotary shaft 22a via a torque limiter, and the cam 30 rotates idle when the roller 22 rotates with a load capable of conveying the document.

  When the cam 30 is rotated to a predetermined position, the protruding cam surface 30a is engaged with the stopper portion 29a of the plate-like member 29, and at this time, the abutting plate 25 is maintained in the open position. Thus, the position at the blocking position is restricted. In the present embodiment, the cam 30 and the plate-like member 29 constitute a stopper member.

  A document detection sensor 6 provided on the document table 5 detects the presence or absence of a document on the document table 5 and outputs detection information to the controller. The controller detects the document based on the detection information from the document detection sensor 6. When it is determined that there is no document on the table 5, the paper discharge motor is driven to return the abutting plate 25 to the blocking position.

  The registration sensor 19a and the paper discharge sensor 19b detect the document on the conveyance path and output detection information to the controller. The controller retains the document on the conveyance path for a predetermined time or more based on the detection information. In this case, it is determined that a jam has occurred, and the paper discharge motor is driven to keep the abutting plate 25 in the open position.

  In the present embodiment, the document detection sensor 6, the registration sensor 19a, the paper discharge sensor 19b, and the controller constitute a paper detection unit.

  On the other hand, the image forming apparatus 1 below the slit glass 3 is provided with a scanner 31 composed of an image sensor, and the scanner 31 is moved in the left-right direction in FIG. 1 by a driving device (not shown). The driving device is controlled by a main body control unit (not shown). When reading image information of a document set on the contact glass 2, a scanner 31 is scanned below the contact glass 2 and a slit is formed. When reading the image information of the document conveyed on the glass 3, the scanner 31 is stopped below the slit glass 3.

  Next, the operation and effect of the automatic document feeder according to the present embodiment will be described. First, a method for conveying a document will be described. When the document bundle P is set on the document table 5, the document detection sensor 6 detects the document bundle P and outputs a paper feed start signal to the controller. At this time, the controller turns on the solenoid 14. When the solenoid 14 is turned on, the second spring 13b is pulled against the urging force of the first spring 13a, and the link 12 is rotated in the clockwise direction in FIG. The protruding portion 10b is lowered to bring the calling roller 7 into contact with the document bundle P.

  At this time, the solenoid 24 simultaneously pulls the second spring 28b against the bias of the first spring 28a to rotate the link 27 in the counterclockwise direction in FIG. The path 32 is retracted to an open position where the path 32 is opened.

  Next, the feeding roller 7, the driving roller 15a, and the pull-out driving roller 17 are rotated by the paper feeding motor, and the conveyance driving roller 20 and the paper discharging driving roller 22 are rotated by the paper discharging motor, so The original is separated and conveyed to the slit glass 3 which is a reading position.

  The brush bristles 40a of the charge eliminating brush 40 are brought into contact with the surface of the document S transported in the transport path 32 by the calling roller 7, and the charge charged on the document S is removed. The electric charge removed by the static eliminating brush 40 is discharged out of the automatic document feeder 1 through the main body frame 42.

  Then, the document that has been read is discharged onto the discharge tray 24 by the conveyance drive roller 20 and the discharge drive roller 22. When the trailing edge of the document is detected by the registration sensor 19a, if it is determined that there is still a document on the document table 5 based on the detection information from the document detection sensor 6, the solenoid 14 is turned on to call the roller. 7 is brought into contact with the original bundle P, and the paper feeding motor is driven to rotate forward to separate subsequent originals.

  On the other hand, when it is determined that there is no document on the document table 5 based on the detection information from the document detection sensor 6, the solenoid 14 is kept OFF. The link 27 is to be rotated in the clockwise direction in the drawing by the first spring 28a. At this time, the cam surface 30a of the cam 30 is engaged with the stopper portion 26a, so that the abutting plate 25 is positioned at the open position. Will remain. Then, after discharging the document in the transport path, the discharge motor is driven in reverse to reversely rotate the rotating shaft 22a, whereby the cam 30 is rotated in reverse to separate the cam surface 30a from the stopper portion 26a. The link 27 rotates in the clockwise direction in FIG. 1 by the urging force of 28a, so that the abutting plate 25 moves to the blocking position protruding on the transport path 32 and returns to the original state. The returning operation of the abutting plate 25 is performed as an initial operation when the image forming apparatus 1 is turned on.

  In the present embodiment, since the neutralizing brush 40 is provided on the abutting plate 25 that restricts the movement of the original bundle P from the original table 5, the electric charge charged on the original S fed into the transport path 32 is removed. In other words, static electricity is unlikely to be generated by the electric charges charged on the document S transported in the transport path 32. Therefore, it is possible to prevent abnormal detection of detection sensors such as the registration sensor 19a and the paper discharge sensor 19b provided in the automatic document placement 1 and abnormalities of electric parts.

  Since the static elimination brush 40 is used as the static elimination member, it is excellent in flexibility and resilience, hardly bent or broken, and a stable static elimination effect can be obtained.

  Since the brush bristles 40a of the static elimination brush 40 protrude in the transport path 32 of the document S at the open position of the abutting plate 25, the brush bristles 40a are slidably contacted with the surface of the document S transported in the transport path 32. Therefore, the charge charged on the document S can be effectively removed.

  Since the charge removal brush 40 is in contact with the main body frame 42 to discharge the charges removed by the charge removal brush 40, it is not necessary to separately provide a grounding member, and the configuration is simple.

  Since the neutralizing brush 40 is provided on the abutting plate 25, a separate mounting member for the neutralizing bra 40 is not required, and the configuration is simple.

  Next, other embodiments will be described. In the following description, parts having the same functions and effects as those of the first embodiment described above are denoted by the same reference numerals, and detailed description of the parts is given. In the following description, differences from the first embodiment will be mainly described. 6 and 7 are diagrams for explaining the driving operation of the butting plate 25 according to the second embodiment.

  As shown in FIG. 6, a cam 43 is provided in the vicinity of the link 27 for rotating the abutting plate 25, and the cam 43 is rotatable by driving of a motor. Further, the drive motor of the cam 43 is connected to a restricting member movement restricting means (control unit) 41. The restricting member movement controlling means 41 causes the brush hair 40a to protrude into the conveyance path 32, and the brush. The abutting plate 25 is controlled so that the bristles 40a are movable between the retracted positions where the hairs 40a are retracted from the transport path 32.

  Until the registration sensor (document leading edge detection sensor) 19a detects the document leading edge, the cam 43 is brought into contact with the link 27 so that the brush bristles 40a of the charge eliminating brush 40 do not protrude upward from the conveyance guide plate 32a. I have to. When the registration sensor 19a detects the leading edge of the document, the restricting member movement restricting means 41 drives the cam 43 as shown in FIG. 7 to rotate the abutting plate 25 to a position where the brush bristles 40a project in the conveying path 32. Move.

  In the present embodiment, the restricting member movement control means 41 can move freely between a protruding position where the brush hairs 40a protrude into the transport path 32 and a retracted position where the brush hairs 40a retract from the transport path 32. Since the abutting plate 25 is controlled, it is possible to prevent an adverse effect on the original document (such as occurrence of a bent end of the original document) caused by the original document coming into contact with the brush bristles 40a.

  Further, the brush bristles 40a are in a position where they are retracted from the conveyance path 32 before the leading edge of the original passes through the static elimination brush 40, and the brush bristles 40a project into the conveyance path 32 after the leading edge of the original passes through the static elimination brush 40. Therefore, it is possible to remove the electric charge charged on the original while preventing the front end from being bent due to the front end of the original contacting the brush bristles 40a.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. As in the modification shown in FIG. 8, the shape of the static elimination brush 40 may be modified, and the brush hair 40a may be provided at a position where the end of the document bundle P abuts on the abutting plate 25. In this case, it is possible to remove the electric charge charged on the entire document bundle P placed on the document table 5.

It is sectional drawing which shows the drive mechanism of the butting plate which concerns on 1st Embodiment. It is a perspective view which shows the drive mechanism of the butting plate which concerns on 1st Embodiment. It is a perspective view which shows the drive mechanism of a calling roller. 1 is a cross-sectional view schematically showing an automatic document feeder according to a first embodiment. 1 is a cross-sectional view illustrating an image forming apparatus including an automatic document feeder according to a first embodiment. In the automatic document feeder concerning 2nd Embodiment, it is a figure which shows the drive mechanism of a butting board, and is sectional drawing which shows when the bristle of a static elimination brush exists in a projecting position. In the automatic document feeder concerning 2nd Embodiment, it is a figure which shows the drive mechanism of a butting board, and is sectional drawing which shows when the bristle of a static elimination brush exists in a retracted position. FIG. 10 is a cross-sectional view showing a driving mechanism of an abutting plate in an automatic document feeder according to a modification.

Explanation of symbols

1 Automatic document feeder 5 Document table (document placement table)
7 Calling roller (paper feed member)
19a Registration sensor (document leading edge detection sensor)
25 Butting plate (regulating member)
32 Document transport path 40 Static elimination brush (static elimination member)
40a Brush hair 41 Restriction member movement control means 43 Body frame

Claims (7)

  A sheet feeding member that sequentially feeds document bundles placed on the document placement table one by one from the top surface, and a regulating member that restricts movement of the document bundle placed on the document placement table from the document placement table And a document transport path for transporting the document fed by the paper feed member in the paper discharge direction, and the regulating member moves between a blocking position for blocking the document transport path and an open position for opening the document transport path An automatic document feeder, wherein the regulating member is provided with a charge eliminating member for removing electric charges charged on the document.   2. The automatic document feeder according to claim 1, wherein the neutralizing member is a neutralizing brush.   3. The automatic document feeder according to claim 2, wherein the automatic document feeder includes a main body frame, and the static elimination brush contacts the main body frame, and the electric charge removed by the static elimination brush is discharged outside the apparatus through the main body frame. Conveying device.   4. The automatic document conveying device according to claim 2, wherein when the restricting member is in the open position, the brush bristles of the static eliminating brush protrude in the document conveying path.   When there is a restricting member movement control means for controlling the movement of the restricting member and the restricting member is in the open position, the restricting member has a protruding position where the bristle protrudes into the document conveying path, and the bristle is within the original conveying path. 4. The apparatus according to claim 2, wherein the control member is movable between a retracted position and a retracted position, and the restricting member movement control unit moves the restricting member between the protruding position and the retracted position. Automatic document feeder.   A document leading edge detection sensor for detecting the document leading edge is provided on the document conveying path. When the document leading edge detection sensor does not detect the document leading edge, the regulating member movement control means retracts the regulating member to the retracted position. 6. The automatic document feeder according to claim 5, wherein when the sensor detects the leading edge of the document, the regulating member movement control means moves the regulating member from the retracted position to the protruding position. An image forming apparatus comprising the automatic document feeder according to any one of claims 1 to 6 and performing image formation by reading a document conveyed by the automatic document feeder.

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