JP2006168995A - Document conveying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a document conveying device preventing document blurring or the like in reading an image to suppress the occurrence of image jitter in the document moving optical fixed type document conveying device. <P>SOLUTION: When conveying a document 1 on contact glass 101 on a reading part 10, the document 1 is pressed onto the contact glass 101 by a conveyor belt 13 suspended across a conveyor belt driving roller 11 and a conveyor belt driven roller 12. Document blurring or the like on the reading part 10 is thereby prevented to suppress the occurrence of image jitter. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a document movement of a copying machine or a facsimile machine, an optical system fixed type ADF, and more particularly to a reading unit.

  2. Description of the Related Art Conventionally, there is one described in Japanese Patent Application Laid-Open No. 2005-151867 for document movement of a copying machine or a facsimile machine and an optical system fixed type ADF (so-called sheet-through type).

  In the document described in Patent Document 1, as shown in FIG. 5, the document P is guided to the reading position 202 through the introduction bus 205 by the conveying roller 204. A guide plate 203 that constitutes a sheet guide in cooperation with the reading position 202 is disposed near the upper position of the reading position 202. Further, below the reading position 202, an optical system 201 for reading image information of the document P is disposed in a fixed state. As described above, reading of image information is performed by pouring while reading the document P while the optical system 201 is fixed.

  In addition, as a document conveying apparatus that holds a document above a reading unit, there is one described in Patent Document 2.

In the document described in Patent Document 2, as shown in FIG. 6, the document sheet 210 is transported to the mapping station 212 through the document feed path 213, and is contact glass 215 by the transport roller 214 above the optical system 211. Is read by the optical system 211.
JP-A-6-247642 JP 7-175279 A

  However, in the case where a guide plate is provided at a position facing the contact glass as in the automatic document feeder described in Patent Document 1, the document is exposed between the guide plate and the contact glass. When the leading edge of the document enters the roller downstream of the reading unit, or when the trailing edge of the document passes through the roller upstream of the reading unit, the conveyance of the document becomes unstable and image jitter occurs.

  On the other hand, in the document processing machine described in Patent Document 2, a roller for bringing the document into contact with the contact glass is provided on the reading unit, but the contact glass is in point contact. Therefore, although it is more advantageous than that described in Patent Document 1, there is a drawback in that image jitter occurs due to unstable conveyance of the document as described above.

  SUMMARY OF THE INVENTION An object of the present invention is to convey a document so that the document is in contact with the surface of the contact glass on the image reading position, thereby preventing screen jitter and realizing highly accurate image reading.

  According to a first aspect of the present invention, in order to achieve the above object, in a document conveying apparatus that reads a document while conveying the document, a document reading unit that reads a document on a contact glass at a predetermined reading position, and a front and rear including the reading position. And a document conveying means for conveying the contact glass while pressing the contact glass, wherein the document conveying means includes an endless conveyance belt and the conveyance belt at the first pressure position. A driving roller for pressing the contact glass; and a pressing roller for pressing the transport belt against the contact glass at a second press position adjacent to the driving roller in a direction extending in the document transport direction of the contact glass; The reading position is arranged between the first pressure position and the second pressure position. It is.

  According to the document conveying device of the present invention, since the document is pressed against the contact glass before and after the reading position, the document comes into contact with the contact glass on the surface before and after the reading position, so there is no blurring of the document, Generation of image jitter can be suppressed.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 4 are views showing an embodiment of a double-sided original reading type of the original conveying apparatus according to the present invention.

  As shown in FIG. 1, the document conveying device includes a document table 2, a paper feed guide plate 3, a bottom plate 4, a roller 5, a separation belt 6, a separation roller 7, a pull-out roller 8, a pull-out driven roller 9, a reading unit 10, and a conveyance. Belt drive roller 11, transport belt driven roller 12, transport belt 13, auxiliary roller 14, auxiliary driven roller 15, paper discharge roller 16, paper discharge lower driven roller 17, paper discharge upper driven roller 18, switching claw 19, paper discharge unit 20 , Reverse roller 21, reverse driven roller 22, intermediate tray 23, paper discharge sensor 24, guide member 50, main body 100 and contact glass 101.

  In this document feeder, a document 1 is set on a document table 2 with the first image surface facing upward, and is fed one by one from the topmost document 1 in response to a signal from the main body 100. The operation procedure will be described below.

  The leading edge of the document 1 is positioned by abutting against the paper feed guide plate 3.

  The bottom plate 4 rises in the direction of arrow A around the fulcrum 4a by SOL (not shown), calls the document 1 from below, and pressurizes the rollers 5. The pressurized originals 1 are fed in order from the top to the separation unit including the separation belt 6, the separation roller 7, and the guide member 50 also serving as an exterior, and are separated one by one.

  The separated document 1 is transported to the reading unit 10 through a first transport path having a pull-out roller 8 and a pull-out driven roller 9. The reading unit 10 includes a contact glass 101, a conveyance belt driving roller 11, a conveyance belt driven roller 12, and a conveyance belt 13, and the conveyance belt 13 obtains conveyance force by applying pressure to the contact glass 101.

  In the case of reading only the first image surface (single-sided mode), the document 1 is read by the reading unit 10, and then the auxiliary roller 14, the auxiliary driven roller 15, the paper discharge roller 16, and the paper discharge follower are driven. It is conveyed to the paper discharge unit 20 through a second conveyance path having the roller 17. The switching claw 19 is normally held at the B position.

  In the case of reading the first image plane and the second image plane (double-sided mode), after reading the first image plane, it is detected that the leading edge of the document has reached the paper discharge sensor 24 through the second conveyance path, and the switching claw 19 Is lowered to the position B ′ by SOL (not shown), and is conveyed onto the intermediate tray 23 through a third conveyance path which is a switchback path having the reverse roller 21 and the reverse driven roller 22. The switching claw 19 has a SOL (not shown) after the document trailing edge has passed through the paper discharge sensor 24 and a predetermined time has elapsed (the time until the document trailing edge has passed the paper discharge roller 16 and reaches the switching claw 19). Is released to return to the position B.

  After the switching claw 19 returns, the reverse roller 21 rotates in the reverse direction and enters the fourth transport path having the paper discharge roller 16 and the paper discharge upper driven roller 18. The leading edge of the original enters the nip portion between the paper discharge roller 16 and the paper discharge upper driven roller 18. At this time, the paper discharge roller 16 is stopped, and so-called skew abutting correction is performed. After completion of the abutting correction, the document 1 passes through the fourth conveyance path and the first conveyance path, and the reading unit 10 reads the image information on the second image surface.

  If the second image surface is read and discharged to the paper discharge unit 20 in this state, the second image surface is stacked face down, and the page order of the document is out of order. The document 1 passes through the second transport path, the switching claw 19 descends to the position B ′, and is transported onto the intermediate tray 23 through the third transport path so that the first image surface is stacked downward. Thereafter, the switching claw 19 returns to the position B, and is discharged to the paper discharge unit 20 through the fourth transport path, the first transport path, and the second transport path.

  FIG. 2 shows an example in which a pressure roller 25 as a pressure member is provided in the conveyor belt 13.

  The pressure roller 25 falls due to its own weight and is in contact with the contact glass 101 with the conveyance belt 13 interposed therebetween.

  As a result, the degree of adhesion between the contact glass 101 and the conveyance belt 13 is increased, and a larger conveyance force than when the pressure roller 25 is not provided can be obtained.

  FIG. 3 shows an example in which a pressure higher than its own weight is applied to the pressure roller 25.

  By providing a compression spring 32 on the bearing 31 of the pressure roller 25 via a receiving member 33, pressure in the direction of arrow C is applied to the pressure roller 25, and a larger conveying force than in the case of only its own weight can be obtained. .

  FIG. 4 shows an example in which the pressure roller 25 is a foam material.

  The pressure roller 25 is fixed, and the radius of the pressure roller 25 in the natural state is set larger than the distance D from the center of the pressure roller 25 to the contact glass 101. For this reason, the pressure roller 25 is crushed, and the pressure roller 25 presses the conveying belt 13 by the repulsive force of the foam material at that time.

It is a figure which shows one Example of the document conveying apparatus which concerns on this invention. It is the figure which provided the pressure roller in the conveyance belt. It is a figure which shows the example which gave the pressure more than self-weight to a pressure roller. It is a figure which shows the example which used the foaming material for the pressure roller. It is a figure which shows an example of the conventional automatic document feeder. It is a figure which shows an example of the conventional document processing machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Document 2 Document table 3 Feeding guide plate 4 Bottom plate 5 Roll 6 Separation belt 7 Separation roller 8 Pull-out roller 9 Pull-out driven roller 10 Reading unit 11 Conveying belt drive roller 12 Conveying belt driven roller 13 Conveying belt 14 Auxiliary roller 15 Auxiliary driven roller 16 Paper discharge roller 17 Lower paper discharge driven roller 18 Upper paper discharge driven roller 19 Switching claw 20 Paper discharge unit 21 Reverse roller 22 Reverse driven roller 23 Intermediate tray 24 Paper discharge sensor 25 Pressure roller 31 Bearing 32 Compression spring 33 Receiving member 50 Guide Member 100 Main body 101 Contact glass 201 Optical system 202 Reading position 203 Guide plate 204 Conveying roller 205 Introduction bus 210 Document paper 211 Optical system 212 Mapping station 213 Document feeding path 214 Conveying roller 215 Contact glass

Claims (1)

In a document transport device that reads a document while transporting it,
An original reading means for reading an original on the contact glass at a predetermined reading position;
Document conveying means for conveying the document on the contact glass while pressurizing the document before and after including the reading position,
The document conveying means includes an endless conveying belt, a driving roller that presses the conveying belt against the contact glass at a first pressure position, and the driving roller in a direction extending in the document conveying direction of the contact glass. A pressure roller that presses the contact belt against the contact glass at a second pressure position next to
An original conveying apparatus, wherein the reading position is arranged between the first pressure position and the second pressure position.

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