JPH07333919A - Document feeder and image reader - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a document feeding device which does not have a document feeding failure even when there is a binding hole on the leading edge side of a document. A document feeding device that separates and feeds documents S on a document stacking tray 1 as a stacking unit one by one.
The paper feed sensor 22 is a binding hole detection sensor that detects the binding holes of the document, and a one-chip microcomputer that is a control unit that controls the feeding and conveyance of the document S.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document feeder such as an automatic document feeder capable of automatically feeding a document,
In particular, it relates to the control method.

[0002]

2. Description of the Related Art Image reading (copy) production in an image reading apparatus, an image forming apparatus, etc. to which an automatic document feeding apparatus (hereinafter referred to as ADF) as a conventional document feeding apparatus of this type is applied. In order to prevent the deterioration of the property, the next original is made to stand by in the middle of the conveyance path during the main body copy, and the original is fed and discharged at the same time when the main body copy is completed.

[0003]

However, in the above-mentioned conventional ADF, there is a timing in which the trailing edge of the previous document and the leading edge of the next document overlap near the document placement reference position. At this time, if the original used is a perforated original and it is set on the leading edge of the originals on the original stacking tray, the holes on both originals will collide with each other during this overlap, causing skewed feeding, etc. Therefore, there is a problem that the image on the original cannot be read.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a document feeding device which does not have a document feeding defect even when a document has a binding hole. To do.

[0005]

In order to achieve the above object, according to the present invention, in an original material feeding device for separating and feeding the originals in a stacking unit one by one, a binding hole for the originals is provided. The present invention is characterized by including a binding hole detection sensor for detecting and a control unit for controlling feeding and conveyance of a document.

When a binding hole is detected in the original, the control means may change the feeding timing of the next original.

[0007]

In the document feeding device configured as described above, the document binding device is provided with the binding hole detection sensor for detecting the binding holes of the document and the control means for controlling the feeding and transportation of the document. When the detection of the hole is detected, it is possible to control so as to eliminate the influence of the feeding and the conveyance due to the binding hole of the document.

When a binding hole is detected in a document, the timing of feeding the next document is changed by the control means so that the binding hole of the document does not overlap with the binding hole of the document to be fed next. You can control.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.

FIG. 1 shows a configuration of an automatic document feeder (hereinafter referred to as ADF) as a document feeder, which is a document stack tray (hereinafter referred to as tray) as a stacking unit for stacking and setting documents S. It is called). Reference numeral 2 is a document stopper, and 4 is a document pressing plate.

The tray 1 is for placing the document S, and is arranged so as to be lower on the document feeding side and inclined downward as it goes in the document feeding direction. As a result, the documents S to be fed are stacked in the delivery direction.

Reference numeral 3 denotes a half-moon roller which is rotated in the direction of the arrow and sends out the document S to the downstream separating portion. When there is no document S on the tray 1, the cutout portion is directed upward and stopped. Controlled by.

Reference numeral 19 denotes a recycle lever, which is driven by a recycle motor 20a at the start of document feeding and placed on the uppermost surface of the document to distinguish the last fed document from the copied document. 20b is a recycle motor encoder,
Reference numeral 20c is a recycle lever reference position detection sensor.

A feeding roller 6 is rotated in the direction of the arrow to feed the original S sent from the tray 1.

Further, 7 and 8 are separation rollers, which rotate the separation belt 9 in the direction of the arrow so that the separation rollers 9 and the feeding roller 6 are the lowest among the originals S stacked on the tray 1. One original S is separated.

The feeding roller 6 and the separating belts 7 and 8 constitute a separating and supplying section.

The original S sent from the separating / feeding section is fed by the feed roller 1 driven by the sheet feeding motor 10a.
It is sandwiched between 1 and 12 and is fed onto the platen glass 15 by the rotation of the feed rollers 11 and 12 in the direction of the arrow. Reference numeral 10b is a paper feed clock disk, and 10c is a paper feed clock sensor.

The paper feed motor 10a also drives the first discharge roller 13a and the second discharge roller 13b.

The entire belt 18 on the platen glass 15
Is an endless belt having a width large enough to cover the entire surface of the document S.
5 has a sufficient coefficient of friction such that it can be slid on the carriage 5 and conveyed in the direction of the arrow.
It is configured so that and do not slip. The drive roller 16 is driven by the belt motor 14a. 14b
Is an electromagnetic brake, 14c is a belt clock disk, 14d
Is a belt clock sensor.

The first discharge roller 13a is the feed roller 12
The original S discharged from the platen glass 15 by the movement of the arrow of the entire surface belt 18 is rotated in the direction of the arrow and is nipped and conveyed.

The original S is sandwiched by the second discharge rollers 13b and discharged onto the tray 1.

Reference numeral 21 is a paper discharge sensor, and 22 is a document detection sensor.

FIG. 2 shows a circuit block diagram of the ADF.

The ADF according to the present invention is mainly composed of a one-chip microcomputer (hereinafter, referred to as a microcomputer) CPU1 as a control means, and further exchanges a signal with a controller CPU2 of a copying machine through communication. Various controls are performed while performing.

Input ports I1 to I6 of the microcomputer CPU1
The document detection sensor 2 provided on the tray 1 described above
3 signal S1, the original S provided on the conveyance path of the original S
Signal S2 of the sheet feed sensor 22 as a binding hole detection sensor for detecting the binding hole of the sheet, signal S3 of the sheet ejection sensor 21, ADF
Open / close switch, recycle lever reference position detection sensor 2
The signal S4 of 0c and the encoder pulse signal P2 for detecting the rotation and the rotation direction of the motor mounted on the shaft of the recycle motor 20a are input. The paper feed sensor 22 is arranged at a position where a general sheet material (original S) binding hole can be detected.

As this detection method, in this embodiment, when the document S is conveyed, immediately after the leading edge of the document S is detected, and when a state of no document is detected for a short time, it is determined that "the binding hole exists".
Of course, the rear end of the document S can be detected similarly.

Further, the interrupt terminal INT of the microcomputer CPU1
1, INT2 and INT3 each have a belt motor 14
The signals from the axis a, the axis of the paper feed motor 10a, the encoder pulse signal P1, the paper feed clock interrupter, and the recycle clock interrupter are input.

These serve as a reference clock for the moving amount of the document feed and a document stacking amount detection clock, and the microcomputer CPU
1 The internal counter performs counting operation.

On the other hand, the output port O1 of the microcomputer CPU1
To O5 are the separation motor 5 and the belt motor 14 described above.
Operation signals of a, the electromagnetic brake 14b, the paper feed motor 10a, and the recycle motor 20a are output, and each output load is controlled via the drivers D1 to D5.

Signals are exchanged with the controller CPU2 of the copying machine including an image reading device having an image reading means (not shown) via communication, and the input I6 to I8 of the microcomputer CPU1 are supplied with respective original feed signals. , A document discharge signal and a mode signal are input, and a copy request signal, a document detection signal, and a document size signal are output from the output ports O6 to O8.

Further, the microcomputer CPU1 has a ROM storing a control program, a RAM as a work area for arithmetic operations, an EEPROM which is a non-volatile memory,
An A / D converter for reading a voltage value and a D / A converter that is a voltage varying unit are connected.

FIGS. 3A and 3B are diagrams showing the principle of binding hole detection.

FIG. 3A is a timing chart of the paper feed sensor / paper feed motor clock pulse when the document S having no binding holes is conveyed.

FIG. 3B is a timing chart of the paper feed sensor / paper feed motor clock pulse when the document S having a binding hole is conveyed.

When the position of the binding hole is on the leading end side of the document S, the time from the rise to the fall of the paper feed sensor is short, and this is detected (sensor ON time or feeding during the sensor ON period). Paper motor clock pulse number) It is possible to detect the presence or absence of a binding hole in the document S.

FIG. 4 shows a flowchart of the present invention.

When the ADF receives a document feed signal from the copying apparatus, the ADF starts feeding the document.

After the document S is conveyed and the paper feed sensor 22 detects the leading edge of the document S and the trailing edge of the document S, respectively,
Whether or not there is a binding hole on the leading end side is determined based on the number of paper feed motor pulses during that period.

When the leading end has a binding hole, the paper feed sensor 22
Is conveyed until the original S completely passes, and further conveyed to the reference position on the platen.

After confirming that the document S is set at the reference position, the copying apparatus shifts to the image forming operation by the image forming means (not shown), and immediately after the completion, transmits the document exchange signal to the ADF.

The ADF shifts to the document discharge operation accordingly. However, if there is a binding hole at the leading edge of the document S, the front document transport distance until the next document is fed is increased by l _0, and the previous document is fed. Make sure that the trailing edge and the leading edge of the next document do not overlap.

Then, this operation is continued until all the documents S are fed and the images are formed.

[0043]

As described above, according to the present invention, the binding hole detecting sensor for detecting the binding hole of the original document and the control means for controlling the feeding and the transportation of the original document are provided. When the detection is detected, it is possible to control so as to eliminate the influence of the feeding and conveying of the document by the binding hole, and even when the document has the binding hole, the conventional document feeding failure can be prevented.

When a binding hole is detected in the document, the control unit changes the feeding timing of the next document so that the binding hole of the document does not overlap with the binding hole of the document to be fed next. It can be controlled, and feeding defects such as oblique feeding due to hole burrs of the binding holes as in the past do not occur.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an automatic document feeder (hereinafter, ADF) as a document feeder according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit of a copying apparatus including an ADF circuit of the present invention and an image reading apparatus to which the ADF is applied.

FIG. 3A and FIG. 3B are diagrams of the binding hole detection principle of the present invention.

FIG. 4 is a flow chart of the present invention.

[Explanation of symbols]

CPU 1 One-chip microcomputer (control means) S Document 1 Document placement tray (stacking unit) 22 Paper feed sensor (binding hole detection sensor)

Claims (3)

[Claims] 1. A document material feeding device for separating and feeding the documents in a stacking unit one by one, a binding hole detection sensor for detecting binding holes of the documents, and a control for controlling feeding and transportation of the documents. An original document feeding device comprising: 2. The document feeder according to claim 1, wherein when a binding hole is detected in a document, the control unit changes the feeding timing of the next document. 3. An image reading device comprising: the document feeding device according to claim 1; and image reading means for reading an image on a document fed by the document feeding device.