JP2003289421A - Sheet member carrying apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet member carrying apparatus capable of suppressing an expansion and contraction difference of front and rear images without managing a drive roller diameter and varying (adjusting) the number of revolutions of a drive motor between a front side and a rear side of the image. <P>SOLUTION: The sheet member carrying apparatus provided with: a sheet placing plate (paper feed tray); a separation means for separating sheet members one by one; a first image read means for reading image information of one side of the sheet member separated by the separation means; a second image read means for reading the image information of the other side of the sheet member separated by the separation means; a first carrying means placed at an upstream of the first read means; and a second carrying means placed at a downstream of the second read means, is configured such that at least a drive transmission means the outer circumferential face of which is driven at a prescribed sheet member carrying speed is placed between the first and second carrying means and the first and second carrying means are driven while being in press contact with the outer circumferential face of the drive transmission means. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material conveying device and an image forming apparatus such as a copying machine or LBP having the sheet material conveying device.

[0002]

2. Description of the Related Art As a conventional sheet material conveying device, there is a device which automatically conveys a sheet material to an image reading portion of an image forming apparatus such as a copying machine. Various devices and the like have been proposed, which have a function of separating the sheets one by one by a separating unit, conveying them to the image reading unit of the image forming apparatus, and further inverting the front and back of the sheet material.

Various methods have been proposed as methods for scanning image information on a sheet material S (a sheet material to be read such as a document) by using this conventional sheet material conveying device, and there are roughly two methods.

One is a method in which a sheet material is placed on a platen and image information is read while moving the reading means, and the other is to fix the reading means at a predetermined position on the platen to make a sheet. This is a method of reading image information while conveying a material.

In recent years, the latter method (hereinafter referred to as flow reading) has been adopted because of the advantages of improved productivity (how much can be processed within a fixed time) and downsizing of the device. In order to improve productivity, a method of providing two reading means and reading image information on the front and back of the sheet material at once is also adopted.

[0006]

However, the sheet material having the structure of adopting the flow-reading method as in the above-mentioned conventional example and reading the image information of the front and back sides at once by the two image reading means without reversing the sheet material. In the conveying device, since a plurality of conveying rollers (driving rollers) are present near the image reading means, there is a difference in the conveying speed of the sheet material passing through the respective image reading means due to variations in the outer diameter of the driving rollers. In some cases, the difference between expansion and contraction occurs in the front and back images.

The details will be described below with reference to FIGS. 7 to 10.

FIG. 7 is a sectional view of a conventional sheet material automatic conveying device, and FIG. 8 is an enlarged sectional view of the vicinity of the image reading portion.

In the figure, numeral 24 'is a large-diameter drive roller for conveying the sheet material by rotating the upstream (idler) roller 23' of the first image reading means, and downstream (idler) roller. It is also a large-diameter drive roller for rotating 25 'to convey the sheet material. Reference numeral 30 'is a drive roller for rotating a downstream (idler) roller 31' of the second image reading means to convey the sheet material.

In this structure, when the image on one side is read by the first image reading means 27 ', the (idler) rollers 23', 25 'are rotated by the large-diameter drive roller 24' to speed the sheet material. When the image is read while being conveyed by V1 (FIG. 9) and the image on the other side is read by the second image reading means 28 ', the (idler) roller 31' is rotated by the drive roller 30 'to remove the sheet material. The image is read while being conveyed at the speed V2 (FIG. 10). At this time, the outer diameters of the large diameter drive roller 24 'and the drive roller 30' are set so that V1 = V2.

However, since the outer diameters of the large-diameter drive roller 24 'and the drive roller 30' always have variations in manufacturing, the intent value V1 = V2 does not necessarily hold, and V1> V2, V.
There were cases where 1 <V2. When V1> V2, the image obtained by the first image reading unit is shrunk than the image obtained by the second image reading unit.

In order to solve this problem, it is possible to (variably) suppress the variation in the outer diameter of each drive roller, or to adjust the rotational speed of the drive motor from the front and back assuming that there is a difference in the outer diameter of the drive rollers. It is proposed that V1 = V2 can be set.

However, in the former case, it is difficult to control the diameter of the driving roller, which leads to an increase in cost. In the latter case, since the number of rotations of the motor is different between the front and back, one drive motor reads the front and back images at the same time. However, since the reading of one side is completed and the other side is read while changing the rotation speed, it is necessary to keep a distance from each other's reading means, leading to an increase in size of the apparatus and an increase in cost.

The present invention has been made in view of the above problems, and an object of the present invention is to prevent the difference in expansion and contraction of images on the front and back sides from changing the rotation number of the drive motor without controlling the diameter of the drive roller. It is an object of the present invention to provide a sheet material conveying device and an image forming apparatus that can be suppressed (without adjustment).

[0015]

In order to achieve the above-mentioned object, the present invention provides a sheet placing table (sheet feeding tray) on which a sheet material is placed, and a sheet material which is arranged on the downstream side of the sheet placing table. The separating means for separating the sheets one by one, the first image reading means for reading one image information of the sheet material separated by the separating means, and the other image information of the sheet material separated by the separating means. A second image reading unit for reading, a first conveying unit arranged upstream of the first reading unit, and a second conveying unit arranged downstream of the second reading unit are provided. In the sheet material conveying device, at least one drive transmitting means whose outer peripheral surface rotates at a predetermined sheet material conveying speed is arranged between the first and second conveying means, and the first conveying means and the second conveying means are arranged. The transportation means of Characterized in that it abuts the rotation to the outer peripheral surface of the drive transmission means.

The present invention also includes the above-described sheet material conveying device,
The image forming apparatus is configured to include an image forming unit that forms an image on a recording sheet with image information of the sheet material read at a predetermined position by the sheet material conveying apparatus.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of an automatic sheet material conveying apparatus to which the present invention is applied will be described in detail below with reference to the drawings. The following embodiments exemplify an automatic sheet material conveying device in an image forming apparatus such as a copying machine.

First, an example of an image forming apparatus main body to which the automatic sheet material conveying apparatus according to the present invention can be applied will be described with reference to FIG. The sheet material automatic conveying device according to the present invention will be described in detail later.

An ADF 80, which is an automatic sheet material conveying device according to the present invention, has a paper feed tray 11 as a mounting table above the sheet material S, and the sheet material S on the paper feed tray 11 is a paper feed means. The roller 1 sequentially feeds out the uppermost sheet material, and the sheets are separated one by one by a separation / conveyance roller 3 and a separation pad 4 which constitute separation means, and conveyed to a platen 18 which is an image reading position of the image forming apparatus main body. It After the image reading is completed, the sheet material S is discharged onto the discharge tray 19 by the discharge rollers 16. still,
The sheet material S is discharged onto the discharge tray 19 in order of page 1 (page 2), page 3 (page 4) ...

The copying machine main body as an image forming apparatus is composed of an image input section 200 (hereinafter referred to as a reader section) and an image output section (hereinafter referred to as a printer section).

The reader unit 200 optically reads the image information recorded on the sheet material S to be read, such as a document, photoelectrically converts the image information, and inputs the image data as image data. , Mirror 20
A scanner unit 204 having three or the like, a mirror 205,
It has 206, a lens 207, an image sensor 208, and the like.

Next, the printer unit 300 which is an image output unit
Will be described.

Reference numeral 800 denotes an upper cassette, and the recording target sheet material such as a recording medium accommodated in the cassette is separated and fed one by one by the action of the separating claw and the feeding roller 801, and is guided to the registration roller 806. Reference numeral 802 denotes a lower cassette, and the recording medium sheet material in the cassette is separated and fed one by one by the action of the separating claw and the feeding roller 803, and is guided to the registration roller 806. Reference numeral 804 denotes a manual feed guide, which guides the sheet material one by one to a registration roller 806 via a roller 805.

A sheet material placing device (deck type) 808 is provided with an intermediate plate 808a which is moved up and down by a motor or the like.
The sheet material to be recorded on the intermediate plate is separated and fed one by one by the action of the feeding roller 809 and the separating claw, and the conveying roller 8
Guided to 10.

Reference numeral 812 is a photosensitive drum, 813 is a reading optical system, 814 is a developing device, 815 is a transfer charging device, and 816 is a transfer charger.
Is a separation charger, and these constitute an image forming unit.

Reference numeral 817 is a conveying belt for conveying the image-formed sheet material, 818 is a fixing device, 819 is a conveying roller, and 820 is a flapper. The sheet material on which the image is formed is guided to the main body discharge roller 821 by the flapper 820 and discharged to the sheet processing apparatus 400 on the downstream side.

An image is formed on the photosensitive drum 812 in accordance with the set number of copies for one sheet material (sheet material to be read such as a document) read on the platen, and the number of copies is made. Sheet material (sheet material to be recorded such as recording medium) for cassettes 800, 802, deck 8
No. 08, an image is fed every time an image is formed on the photoconductor drum 812. The registration roller 806 aligns the image on the photosensitive drum 812 with the sheet material to be recorded.
Done by

Reference numeral 900 denotes an intermediate tray which is used to form an image once when an image is formed on both sides of a recording target sheet material or when an image is formed on one side of the recording target sheet material (multiplexing). The sheet material on which is formed is stocked. 901
Is a transport roller, 902 is a transport belt, 903 is a flapper, 904 is a transport belt, and 905 is a transport roller.
In case of double-sided copying, the intermediate tray 9 is passed through the path 906.
Lead the sheet material to 00, and in the case of multiple copy, arrow 90
Guide the sheet material to the intermediate tray through the path indicated by 7.

The sheet material placed on the intermediate tray 900 includes auxiliary rollers 909 and 910 and a pair of forward / reverse separation rollers 9.
By the action of 11, the sheets are separated one by one from below and are re-fed. The re-fed sheet material is conveyed by the conveyance roller 91.
3,914,915 and 810, registration roller 806
Is guided to the image forming unit via. After the image is formed, it is discharged in the same manner as described above.

For one sheet material (sheet material to be read such as a manuscript) read on the platen, according to the set number of copies, first, the number of sheet materials (recording of recording medium etc.) A single-sided copy of the target sheet material) is made, and they are placed on the intermediate tray 900. After that, the inside and outside of the sheet material to be read is reversed in the ADF 80, and the sheet material is guided again to the reading unit (platen 18) to read the image information. Read image (image information)
Is formed on the sheet material to be recorded, which is re-fed from the intermediate tray 900.

The image-formed sheet material discharged from the main body of the copying machine is discharged to a sheet processing apparatus 400 (also called a finisher).

In the non-sort mode, the sheet material carried in from the main body of the copying machine is ejected onto the sample tray 405 by the ejection roller 404 via the buffer roller 401, the flapper 402, and the non-sort mode path 403, and placed. To be done. In the sort mode, the buffer roller 401, the flapper 406, and the sort mode path 407.
Through the discharge roller 408, the sheet is discharged onto the processing tray 409 serving as an intermediate tray and temporarily placed.

The sheet material bundle on the processing tray 409 is aligned at both ends in the direction intersecting the sheet conveying direction by an aligning member (not shown), and the rear end portion of the sheet material bundle is bound by the stapler 410 as necessary. After that, the bundle discharge rollers 411 discharge and stack the stack tray 412.

Next, the sheet material conveying device (ADF80) according to the present invention will be described in detail with reference to FIGS.

1 is a sheet feeding roller as a feeding means, 2 is an arm for moving the sheet feeding roller 1 up and down around a shaft 5, and 3 and 4 are separating means for separating sheet materials one by one. Separation conveyance roller and separation pad, 6
Is a fixed guide for smoothly guiding the sheet material from the feeding means to the separating means, 7 is a timing belt for transmitting the drive of the motor M to the feeding means, and 8 and 9 are stretched with the timing belt. A pulley 11 is a sheet feed tray as a mounting table on which a sheet material to be read such as a document is set. A sheet material width 10 is a sheet material width for regulating the width of the sheet material to be read set on the sheet feeding tray. It is a regulation plate.

Further, reference numeral 12 is a spring clutch as a pressure applying means, and when the motor M rotates in the normal direction (in FIG. 3, the paper feed roller 1 and the separation / conveyance roller 3 rotate in the direction of the arrow, the arm 2
Goes down. ), The paper feed roller 1 applies a certain constant pressure (torque) after landing on the upper surface of the sheet material on the paper feed tray 11, and when the arm 2 is rotated in the reverse direction (direction opposite to the arrow), Lock to raise.

Reference numeral 13 is a shaft which is the center of rotation of the paper feed roller 1. Reference numeral 14 is a swing guide as a guide means, which is a guide for guiding the sheet material from the paper feed roller 1 to the separation / conveyance roller 3, and is swingable around a fulcrum b. Reference numeral 15 denotes an elastic member such as an elastically deformable mylar, which is attached to the tip portion (downstream side) of the swing guide 14. Reference numeral 17 is a sheet material stopper.

Reference numeral 21 denotes a pair of registration rollers for carrying out skew feeding (registration removal) of the sheet material to be read which has been separated into one sheet by the separating means, and 24 denotes rollers 22, 23, 25, 29 around the reading portion. It is a large-diameter roller that drives 30, 31 and is the only drive roller when reading image information on a sheet material.

Reference numeral 28 denotes a contact sensor (second reading means) provided in the ADF 80, which reads image information on the surface opposite to the first reading means 27.

Reference numeral 16 denotes a pair of discharge rollers for discharging the read sheet material onto the discharge tray 19.

In the above construction, the sheet material bundle set in the sheet feeding tray 11 is fed from the uppermost portion by the feeding means (sheet feeding roller 1), and when a plurality of sheets are fed simultaneously, the sheet material bundle is arranged downstream thereof. The separating means (separation conveyance roller 3 and separation pad 4) separates the sheets one by one, and only the uppermost sheet is further conveyed to the registration roller pair 21 located downstream. The sheet material conveyed to the registration roller pair 21 is registered and further conveyed to the downstream image reading means (first image reading means 27, second image reading means 28).

The sheet material conveyed to the image reading means is read between the (idler) rollers 23 and 25 by the first image reading means 27 to read the image information on one side thereof, and then the (idler) roller 25, The image information on the other surface is read by the second image reading means between the (idler) roller pair 30/31.

At this time, the (idler) rollers 23, 25
Is rotated by the drive roller 24, and the (idler) roller pair 30/31 is also rotated by the drive roller 24 via the (idler) roller 29. Therefore, during the image reading by the first and second image reading means, since the sheet material is always conveyed at the speed V, the expansion / contraction difference of the image does not occur.

After that, the read sheet material is discharged onto the discharge tray 19 by the discharge roller pair 16.

In this embodiment, the drive roller 24 and the (idler) roller 29 are used as the drive transmission means to describe the features, but the present invention is not limited to this.
The effect of the present invention can also be obtained by using a belt-shaped drive transmission means.

[0046]

As is apparent from the above description, according to the present invention, the sheet material is conveyed by the same driving roller during the image reading by the first image reading means and the second image reading means. As a result, there is no difference in conveyance speed, and there is no difference in expansion / contraction of the front and back images.

[Brief description of drawings]

FIG. 1 is a sectional view of a sheet material conveying device of the present invention.

FIG. 2 is a cross-sectional view (enlarged view) of a reading unit of the sheet material conveying device of the present invention.

FIG. 3 is a cross-sectional view of a sheet feeding unit and a separating unit of the sheet material conveying device of the present invention.

FIG. 4 is a plan view (view from arrow X in FIG. 3) of the sheet feeding unit and the separating unit of the sheet material conveying device of the present invention.

FIG. 5 is a cross-sectional view (at the time of feeding the sheet material) of the sheet feeding portion and the separating portion of the sheet material conveying device of the present invention.

FIG. 6 is a cross-sectional view of a sheet material conveying device of the present invention and an applicable image forming apparatus main body.

FIG. 7 is a sectional view of a conventional sheet material conveying device.

FIG. 8 is a cross-sectional view (enlarged view) of a reading unit of a conventional sheet material conveying device.

FIG. 9 is a cross-sectional view of a reading unit of a conventional sheet material conveying device (when reading one surface).

FIG. 10 is a cross-sectional view of the reading unit of the conventional sheet material conveying device (when reading the other surface).

[Explanation of symbols]

M motor S sheet material b fulcrum 1 Paper feed roller 2 Separation pad 3 Separation and conveyance rollers 4 Separation pad 5 shafts 6 Fixed guide 7 Timing belt 8,9 pulley 10 Sheet material width control plate 11 Paper tray 12 Spring clutch 13 shaft 14 Swing guide 15 Elastic member 16 Paper ejection roller 17 Sheet material stopper 18,18 'platen 19 Output tray 21 cash register 22,23 (idler) rollers

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H076 AA04 AA58 BA17 BA24 BA35                       BA39 BA58 BA83 BA87                 3F049 AA10 DA12 EA21 LA02 LB03                 5C062 AA02 AA05 AB02 AB17 AB22                       AB32 AC09 AC12 AD06 BA00                 5C072 AA01 BA01 BA02 CA02 DA02                       DA04 DA25 EA05 EA07 NA01                       WA02 XA01

Claims (2)

[Claims] 1. A sheet placing table (paper feed tray) on which a sheet material is placed, a separating means arranged downstream of the sheet placing table and separating sheet materials one by one, and separated by the separating means. A first image reading means for reading one image information of the sheet material, a second image reading means for reading the other image information of the sheet material separated by the separating means, and the first image reading means. A sheet material conveying device comprising a first conveying unit arranged upstream of a reading unit and a second conveying unit arranged downstream of the second reading unit, wherein the first and second conveying units are provided. In between, at least one drive transmission means whose outer peripheral surface rotates at a predetermined sheet material conveying speed is arranged, and both the first conveying means and the second conveying means contact the outer peripheral surface of the drive transmitting means. To rotate The sheet material conveying apparatus according to symptoms. 2. A sheet material conveying device according to claim 1, and an image forming means for forming image information of the sheet material read at a predetermined position by the sheet material conveying device on a recording sheet. An image forming apparatus characterized by.