JP2010089894A - Automatic document feeder and image forming device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a document delivery tray superior in stacking performance. <P>SOLUTION: This automatic document feeder has a document carrying part for carrying and delivering a document and the document delivery tray for receiving the delivered document, and is provided so that the document delivery tray has at least two ribs extending in the document delivering direction on a surface of the document delivery tray, an auxiliary tray extractably arranged in the document delivering direction in the document delivery tray, and a rib moving mechanism for expanding a rib interval by interlocking with extraction operation of the auxiliary tray. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

    The present invention relates to an automatic document feeder in an image forming apparatus such as a copying machine, a multifunction machine, or a facsimile machine.

A document discharge tray provided in the automatic document feeder needs to properly stack (stack) a plurality of discharged documents. Therefore, in order to improve stacking (stacking) properties and make it easy to take a document, a document discharge tray provided with ribs is known (for example, see Patent Document 1).
This document discloses a paper discharge tray device in which the protrusion height of the lumbar ribs is increased in conjunction with the pull-out operation of the auxiliary tray.
JP 2000-31561 A

  However, there are various sizes of documents, and there is a problem that stacking performance of documents cannot be improved only by changing the protruding amount of the rib with respect to the discharged document. In particular, when a large-sized document that has been ejected is curled and ejected in a concave direction or a convex direction, the paper is shifted to the left or right, resulting in poor stacking on the document tray. The present invention has been made in view of such circumstances, and provides an automatic document feeder capable of obtaining a good stacking property corresponding to a change in document size.

  The present invention includes a document transport unit that transports and discharges a document, and a document discharge tray that receives the document to be discharged. The document discharge tray extends on the surface of the document discharge tray along the document discharge direction. Provided is an automatic document feeder including a rib, an auxiliary tray provided on a document discharge tray so as to be able to be pulled out in a document discharge direction, and a rib moving mechanism that increases a rib interval in conjunction with a pull-out operation of the auxiliary tray. is there.

  The interval between the ribs is increased in conjunction with the drawing operation of the auxiliary tray. That is, since the rib interval is set corresponding to the document size, good stacking properties can be obtained.

An automatic document feeder according to the present invention includes a document transport unit that transports and discharges a document, and a document discharge tray that receives the document to be discharged. The document discharge tray is disposed on the surface of the document discharge tray along the document discharge direction. And a rib moving mechanism for enlarging the interval between the ribs in conjunction with the drawing operation of the auxiliary tray. To do.
The rib may be composed of two ribs, and the moving mechanism may move the two ribs in a direction orthogonal to the document discharge direction.
The rib may be composed of two ribs, and the moving mechanism may move the two ribs so that they widen toward the document discharge direction.
The moving mechanism may enlarge the interval between the ribs in proportion to the pull-out amount of the auxiliary tray.
From another viewpoint, the present invention provides an image forming apparatus provided with the above document feeder.

The present invention will be described in detail below based on the embodiments shown in the drawings.
FIG. 1 is an explanatory view of the configuration of an image forming apparatus in which the automatic document feeder of the present invention is used. The image forming apparatus 100 forms multicolor and single color images on a predetermined sheet (recording paper) in accordance with image data transmitted from the outside. The image forming apparatus 100 includes an apparatus main body 200, an automatic document processing apparatus 300, and the like. It is comprised by. The automatic document processor 300 includes an automatic document feeder 310 and a document scanning unit 320. The apparatus main body 200 includes an exposure unit 1, a developing device 2, a photosensitive drum 3, a cleaner unit 4, a charger 5, an intermediate transfer belt unit 6, a fixing unit 7, a paper feed cassette 81, a paper discharge tray 91, and the like. It is configured.

  An automatic document processing apparatus 300 according to the present invention provided at the upper part of the apparatus main body 200 is provided with a document placing table 120 made of transparent glass on which a document is placed, and an automatic document feeding is placed above the document placing table 120. A device 310 is attached. The automatic document feeder 310 automatically conveys a document on the document table 120. Further, the document can be manually placed by opening the automatic document feeder 310 and opening the top of the document table 120.

  Image data handled in the image forming apparatus 100 corresponds to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y). Accordingly, four developing devices 2, photosensitive drums 3, charging devices 5, and cleaner units 4 are provided to form four types of latent images corresponding to the respective colors, and are respectively provided in black, cyan, magenta, and yellow. These are set to form four image stations.

  The charger 5 is a charging means for uniformly charging the surface of the photosensitive drum 3 to a predetermined potential. In addition to the charger type as shown in FIG. 1, a contact type roller type or brush type charger is used. Sometimes used.

  The exposure unit 1 is configured as a laser scanning unit (LSU) provided with a laser emitting portion, a reflection mirror, and the like. The exposure unit 1 includes a polygon mirror that scans a laser beam and optical elements such as a lens and a mirror for guiding the laser beam reflected by the polygon mirror to the photosensitive drum 3. As the exposure unit 1, for example, an EL or LED writing head in which light emitting elements are arranged in an array can be used.

  The exposure unit 1 has a function of forming an electrostatic latent image corresponding to the image data on the surface thereof by exposing the charged photosensitive drum 3 according to the input image data. The input image data is data acquired from a document and input to the apparatus main body 200 in the automatic document processing apparatus 300 as will be described later.

  The developing device 2 visualizes the electrostatic latent images formed on the respective photosensitive drums 3 with toner of four colors (hereinafter referred to as YMCK). The cleaner unit 4 removes and collects toner remaining on the surface of the photosensitive drum 3 after development and image transfer.

  The intermediate transfer belt unit 6 disposed above the photosensitive drum 3 includes an intermediate transfer belt 61, an intermediate transfer belt driving roller 62, an intermediate transfer belt driven roller 63, an intermediate transfer roller 64, and an intermediate transfer belt cleaning unit 65. I have. Four intermediate transfer rollers 64 are provided corresponding to each color for YMCK.

  The intermediate transfer belt driving roller 62, the intermediate transfer belt driven roller 63, and the intermediate transfer roller 64 are driven to rotate while the intermediate transfer belt 61 is stretched. Each intermediate transfer roller 64 provides a transfer bias for transferring the toner image on the photosensitive drum 3 onto the intermediate transfer belt 61.

  The intermediate transfer belt 61 is provided so as to be in contact with each photoconductor drum 3, and the toner images of the respective colors formed on the photoconductor drum 3 are sequentially transferred to the intermediate transfer belt 61 and transferred. Further, it has a function of forming a color toner image (multicolor toner image) on the intermediate transfer belt 61. The intermediate transfer belt 61 is formed in an endless shape using, for example, a film having a thickness of about 100 μm to 150 μm.

  Transfer of the toner image from the photosensitive drum 3 to the intermediate transfer belt 61 is performed by an intermediate transfer roller 64 that is in contact with the back side of the intermediate transfer belt 61. A high-voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) is applied to the intermediate transfer roller 64 in order to transfer the toner image.

  The intermediate transfer roller 64 is a roller whose base is a metal (for example, stainless steel) shaft having a diameter of 8 to 10 mm and whose surface is covered with a conductive elastic material (for example, EPDM, urethane foam, or the like). With this conductive elastic material, a high voltage can be uniformly applied to the intermediate transfer belt 61. In this embodiment, a roller shape is used as the transfer electrode, but a brush or the like can also be used.

  As described above, the electrostatic images visualized according to the respective hues on the respective photosensitive drums 3 are laminated on the intermediate transfer belt 61. As described above, the laminated image information is transferred onto the sheet by the transfer roller 10 disposed at a contact position between the sheet and the intermediate transfer belt 61 described later by the rotation of the intermediate transfer belt 61.

  At this time, the intermediate transfer belt 61 and the transfer roller 10 are pressed against each other at a predetermined nip, and a voltage for transferring the toner onto the sheet is applied to the transfer roller 10 (the polarity opposite to the toner charging polarity (−)). (+) High voltage). Further, in order to obtain the nip constantly, the transfer roller 10 uses either the transfer roller 10 or the intermediate transfer belt drive roller 62 as a hard material (metal or the like), and the other as a soft material (elasticity such as an elastic roller). A rubber roller, a foaming resin roller, or the like) is used.

  Further, as described above, the toner attached to the intermediate transfer belt 61 by contacting the photosensitive drum 3 or the toner remaining on the intermediate transfer belt 61 without being transferred onto the sheet by the transfer roller 10 is used in the next step. Therefore, the intermediate transfer belt cleaning unit 65 is configured to remove and collect the toner. The intermediate transfer belt cleaning unit 65 includes a cleaning blade as a cleaning member that comes into contact with the intermediate transfer belt 61. The intermediate transfer belt 61 that comes into contact with the cleaning blade is supported by an intermediate transfer belt driven roller 63 from the back side. ing.

  The paper feed cassette 81 is a tray for storing sheets (recording paper) used for image formation, and is provided below the exposure unit 1 of the apparatus main body 200. A sheet used for image formation can also be placed on the manual paper feed tray 82. A paper discharge tray 91 provided above the apparatus main body 200 is a tray for collecting printed sheets face down.

  Further, the apparatus main body 200 is provided with a substantially vertical sheet conveyance path S for sending the sheets of the sheet feeding cassette 81 and the manual sheet feeding tray 82 to the sheet discharge tray 91 via the transfer roller 10 and the fixing unit 7. It has been. In the vicinity of the paper transport path S from the paper feed cassette 81 or the manual paper feed tray 82 to the paper discharge tray 91, pickup rollers 11a and 11b, a plurality of transport rollers 12a to 12d, a registration roller 13, a transfer roller 10, and a fixing unit. 7 etc. are arranged.

  The conveyance rollers 12 a to 12 d are small rollers for promoting and assisting conveyance of the sheet, and a plurality of conveyance rollers 12 a to 12 d are provided along the sheet conveyance path S. The pickup roller 11 a is provided near the end of the paper feed cassette 81, picks up sheets one by one from the paper feed cassette 81, and supplies them to the paper transport path S. Similarly, the pickup roller 11 b is provided near the end of the manual paper feed tray 82, picks up sheets one by one from the manual paper feed tray 82, and supplies them to the paper transport path S.

FIG. 2 is an explanatory diagram of the configuration of the automatic document processing apparatus 300. As shown in the figure, the automatic document processing apparatus 300 includes an automatic document feeder 310 and a document scanning unit 320.
The automatic document feeder 310 includes a document tray 101 on which the document R is stacked, a transport path 104a, 104b, 104c for transporting the document, and a paper discharge tray 117 that receives a document discharged from the transport path 104b.
The document scanning unit 320 includes a lamp unit 130 on which the light source 109 and the first mirror 110 are mounted, a mirror unit 140 on which the second mirror 114 and the third mirror 113 are mounted, a lens 111, and a CCD 112.

  In such an automatic document processing apparatus 300, when one or more single-sided originals are placed on the original tray 101 with the front side (image side) facing upward, the original placement detection sensor 116 detects the originals. Then, the originals are successively carried into the conveyance path 104 a one by one by the pickup roller 115, and conveyed to the conveyance path 104 b through the original reading glass 107.

  The document being conveyed is illuminated by the light source 109 via the document reading glass 107, and the reflected light from the document is received by the CCD 112 via the first mirror 110, the second mirror 114, the third mirror 113, and the lens 111, Image data is read. The read original is sequentially discharged from the conveyance path 104 b to the original discharge tray 117 by the discharge roller 126. The discharged originals are sequentially stacked on the original discharge tray 117 by the ribs 25a and 25b (FIG. 4) and the auxiliary tray 24.

  In addition, when the original is a double-sided original and the double-sided image is read, the original whose surface image data has been read as described above is used for recoil by the reverse rotation of the discharge roller 126 immediately before being discharged to the original discharge tray 117. To the transport path 104c. Then, the document is discharged to the document discharge tray 117 through the conveyance paths 104a and 104b with the front and back sides reversed. At this time, the inverted original, that is, the image data on the back side is read by the CCD 112 through the original reading glass 107 as described above.

  When the automatic document feeder 310 is not used, the document is manually placed on the document placing table 120 with the surface (image surface) facing down. Then, the lamp unit 130 and the mirror unit 140 move to scan the document, and the image data of the document is read by the CCD 112.

  The image data read in this way is input to the apparatus main body 200 as described above, and an image is formed on the sheet supplied from the paper feed cassette 81 or the manual paper feed tray 82 based on the image data. The

3 is a front view of the document discharge tray 117 as viewed from the document discharge side, FIG. 4 is a top view thereof, and FIGS. 5, 6, and 7 are views taken along arrows AA, BB, and CC in FIG. 8 is a cross-sectional view taken along the line DD of FIG.
In these drawings, an auxiliary tray 24 is accommodated in the housing 21, and a handle 23 for pulling out the auxiliary tray 24 protrudes from the front end of the auxiliary tray 24 through the front opening 22 of the housing 21. Further, ribs 25 a and 25 b protrude from the short openings 26 a and 26 b on the upper surface of the housing 21. Further, a pair of rib movement guides 27 a and 27 b provided with locking bosses 36 a and 36 b that sandwich the auxiliary tray 24 from both sides are accommodated inside the housing 21.

  Ribs 25a and 25b stand on the rib movement guides 27a and 27b, respectively. The rib movement guide 27a has a pair of long holes 28a and 28b, and the rib movement guide 27b has a pair of long holes 28A and 28B. Guide bosses 29a and 29b projecting upward from the inner bottom surface of the casing 21 are inserted into the long holes 28a and 28b, respectively. Guide bosses 29A and 29B projecting from the inner bottom surface of the housing 21 are inserted into the long holes 28A and 28B, respectively. Accordingly, the rib movement guides 27a and 27b can slide in the directions of the arrows X1 and X2 in the housing 21, respectively.

  The rib movement guides 27a and 27b are urged in the directions of the arrows X2 and X1 by the tension springs 30 and 31 provided at both ends, respectively. The auxiliary tray 24 is mounted on a slide base 32 integrally formed on the inner bottom surface of the casing 21, and guide bosses 33 and 34 standing on the slide base 32 are formed at the center of the auxiliary tray 24. It is inserted into the hole 35. As a result, the auxiliary tray 24 can slide on the slide table 32 in the directions of arrows Y1 and Y2. The locking bosses 36 a and 36 b provided on the rib movement guides 27 a and 27 b are in contact with both side surfaces of the auxiliary tray 24. That is, the auxiliary tray 24 is sandwiched between the locking bosses 36a and 36b by the tensile force of the tension spring.

  In addition, two pairs of arc-shaped concave portions 37a, 37b and 38a, 38b are symmetrically formed on the inclined surfaces on both sides of the auxiliary tray 24, and when the auxiliary tray 24 is pulled out from the housing 21 in the direction of the arrow Y1, The locking bosses 36a and 36b are locked to each other.

The operation of the document discharge tray 117 having such a configuration will be described.
First, when the document is discharged in the longitudinal direction in A4 size, the auxiliary tray 24 is used in the state shown in FIG. 4 without being pulled out. At this time, the interval L (FIG. 3) between the ribs 25a and 25b is 100 mm.

  Next, when the document is discharged in the longitudinal direction in B4 size, the auxiliary tray 24 is located at an intermediate position where the arc-shaped concave portions 37a and 37b are locked to the locking bosses 36a and 36b, respectively, according to the length of the document. It is pulled out and used. At this time, the distance L (FIG. 3) between the ribs 25a and 25b is increased to 140 mm in proportion to the drawing length of the auxiliary tray 24.

  Next, when the document is discharged in the longitudinal direction in A3 size, the auxiliary tray 24 is the longest position where the arc-shaped recesses 38a and 38b are locked to the locking bosses 36a and 36b, respectively, according to the length of the document. (FIG. 9) is pulled out and used. At this time, the interval L (FIG. 3) between the ribs 25a and 25b is enlarged to 160 mm in proportion to the drawing length of the auxiliary tray 24.

The user, when pulling out the auxiliary tray 24, perceives whether or not the locking bosses 36a and 36b are locked to the arc-shaped recesses 37a and 37b or 38a and 38b with a click feeling, and is B4 size or A3 size. It is possible to confirm the amount of the auxiliary tray 24 that corresponds to.
Further, the document sizes “B4” and “A3” are displayed on the auxiliary tray 24 (see FIG. 8), and the relationship between the pull-out amount of the auxiliary tray 24 and the document size can be visually confirmed.

  FIG. 10 is a correspondence diagram showing a modification of the embodiment shown in FIG. In this modification, the rib movement guides 27a and 27b are slightly shortened in the longitudinal direction, and fulcrum pins 40a and 40b are provided instead of the guide bosses 29a and 29A. Fan-shaped openings 39a and 39b are provided instead of the short openings 26a and 26b, and arc-shaped elongated holes 41a and 41b are provided instead of the elongated holes 28b and 28B. Accordingly, the rib movement guides 27a and 27b can be rotated around the fulcrum pins 40a and 40b.

The operation of such a modification will be described.
First, when the document is discharged in the longitudinal direction in A4 size, the auxiliary tray 24 is used in the state shown in FIG. 10 without being pulled out. At this time, the ribs 25a and 25b are parallel to each other.

  Next, when the document is discharged in the longitudinal direction in B4 size, the auxiliary tray 24 is located at an intermediate position where the arc-shaped concave portions 37a and 37b are locked to the locking bosses 36a and 36b, respectively, according to the length of the document. It is pulled out and used. At this time, the ribs 25a and 25b are rotated by an angle proportional to the drawing length of the auxiliary tray 24 so that the ribs 25a and 25b spread toward the end in the document discharge direction, and the rib interval is increased corresponding to the angle.

Next, when the document is discharged in the longitudinal direction in A3 size, the auxiliary tray 24 is the longest position where the arc-shaped recesses 38a and 38b are locked to the locking bosses 36a and 36b, respectively, according to the length of the document. (FIG. 9) is pulled out and used. At this time, the ribs 25a and 25b are rotated by an angle proportional to the pull-out length of the auxiliary tray 24 so that the ribs 25a and 25b further expand in the document discharge direction, and the rib interval is expanded as shown in FIG.
As described above, according to the above-described embodiment and modification, the rib interval is adjusted according to the document size, so that the document to be discharged is satisfactorily stacked on the document discharge tray.

1 is a configuration explanatory diagram of an image forming apparatus according to the present invention. FIG. 1 is a configuration explanatory diagram of a document processing apparatus according to the present invention. FIG. It is a front view of the document discharge tray according to the present invention. It is a top view of the document discharge tray according to the present invention. It is AA arrow sectional drawing of FIG. It is a BB arrow sectional view of Drawing 4. It is CC sectional view taken on the line of FIG. It is DD sectional view taken on the line of FIG. FIG. 5 is an operation explanatory diagram of the document discharge tray shown in FIG. 4. FIG. 5 is a view corresponding to FIG. 4 showing a modification of the present invention. It is operation | movement explanatory drawing of the modification shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exposure unit 2 Developing device 3 Photoconductor drum 4 Cleaner unit 5 Charger 6 Intermediate transfer belt unit 7 Fixing unit 10 Transfer roller 11a, 11b Pickup roller 12a-12d Conveyance roller 13 Registration roller 21 Case 22 Opening 23 Handle 24 Auxiliary tray 25a, 25b Rib 26a, 26b Short opening 27a, 27b Rib movement guide 28a, 28b Long hole 28A, 28B Long hole 29a, 29b Guide boss 29A, 29B Guide boss 30 Tension spring 31 Tension spring 32 Slide table 33 Guide boss 34 Guide boss 35 Long hole 36a Locking boss 36b Locking boss 37a, 37b Arc-shaped recess 38a, 38b Arc-shaped recess 39a, 39b Fan-shaped opening 40a, 40b Support pin 41a, 41b Arc-shaped slot 61 Intermediate transfer bell 62 Intermediate transfer belt driving roller 63 Intermediate transfer belt driven roller 64 Intermediate transfer roller 65 Intermediate transfer belt cleaning unit 81 Paper feed cassette 82 Manual feed tray 91 Paper discharge tray 100 Image forming apparatus 101 Document trays 104a, 104b, 104c Conveying path 107 Document reading glass 109 Light source 110 First mirror 111 Lens 112 CCD
113 Third Mirror 114 Second Mirror 115 Pickup Roller 116 Document Placement Detection Sensor 117 Document Discharge Tray 120 Document Placement Table 126 Discharge Roller 130 Lamp Unit 140 Mirror Unit 200 Main Body 300 Automatic Document Processing Device 310 Automatic Document Feeder 320 Document Scan Unit R Document S Paper transport path

Claims (5)

  A document transport unit that transports and discharges a document, and a document discharge tray that receives the document to be discharged. The document discharge tray includes at least two ribs that extend along the document discharge direction on the surface of the document discharge tray, and a document An automatic document feeder comprising: an auxiliary tray provided on a discharge tray so as to be able to be pulled out in a document discharge direction; and a rib moving mechanism that expands a rib interval in conjunction with a drawing operation of the auxiliary tray.   2. The automatic document feeder according to claim 1, wherein the rib includes two ribs, and the moving mechanism moves the two ribs in a direction orthogonal to the document discharge direction.   The automatic document feeder according to claim 1, wherein the rib includes two ribs, and the moving mechanism moves the two ribs so as to be widened toward the document discharge direction.   The automatic document feeder according to any one of claims 1 to 3, wherein the moving mechanism enlarges the interval between the ribs in proportion to the pull-out amount of the auxiliary tray.   An image forming apparatus comprising the automatic document feeder according to claim 1.

Images