JPH03123365A - Automatic document feeder - Google Patents

Abstract

PURPOSE:To shorten the time required for processing all documents by processing two or more documents placed on a document placing part so that the second and subsequent documents are fed from a waiting position the instant that the first one is ejected from an exposing part. CONSTITUTION:When a roller 7 comes into press-contact with the documents on the placing part 1 an electromagnetic clutch and a motor drive rollers 7 to 15 in the direction of an arrow, and the first document is fed. During a period when the leading edge of the second one does not reach a position in which it receives the carrying force of a belt 11 and when the leading edge of the first one does not reach a position in which it abuts on a stopper 13 after the leading edge of the second one passes through a detecting means 10, the clutch is turned off, and the leading edge of the second one is awaited in a position in which the detecting means 10 and the belt 11 take the document. At the end of scanning and exposure, the clutch and the motor are again turned on. The first one is ejected to a tray 16, while the waiting second one is fed to the belt 11. When the trailing edge of the second one is out of the roller 7, the third one is fed from the placing part. Since the second and subsequent ones are fed from the waiting position the instant that the previous one is ejected, document processing is sped up.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic document feeder used in copying machines, document reading devices, etc. The present invention relates to an automatic document feeding device equipped with a feeding conveyance means for feeding documents one after another, and an above-platen conveyance means for bringing a document received from the feeding conveyance means to an exposure section on a platen glass, leaving it stationary, and then ejecting it from the exposure section.

[Conventional technology]

Conventionally, the automatic document feeder described above always feeds originals directly from the document stacking section to the exposure section, and the second and subsequent documents are fed in at the same time as the previous document is ejected from the exposure section. It was something. In this case, the entire document processing speed is slow because it takes the same amount of time to transport all the documents from the document stacking section to the exposure section until the documents are placed on the exposure section.

[Problem to be solved by the invention]

According to the present invention, the time it takes for the second and subsequent documents sent from the document stacking section to be placed on the W source section is shorter than the time required to transport them from the document stacking section to the exposure section, thereby reducing the overall To provide an automatic document feeding device capable of increasing processing speed, having a relatively simple structure, and facilitating drive control.

[Means to solve the problem]

The automatic document feeder of the present invention is such that the drive system of the feed conveyance means can be stopped even while the above-platen conveyance means is being driven, so that the drive system of the feed conveyance means can be stopped even when the above-platen conveyance means is being driven. When the document detecting means in the document stacking section detects the presence of a document, the drive is started before the second document reaches the platen conveying means and before the first document reaches the exposure section. Then, as long as the document detecting means detects the presence of a document, the document in the standby position is sent to the above-platen conveying means, and the document in the document stacking section is kept on standby. The above-mentioned detection means repeats driving of the feeding conveying means to bring the document to the original position, and driving of the platen conveying means to eject the document from the exposure section and bring the document at the standby position sent from the feeding conveyance means to the exposure section. The present invention is characterized in that, when a blank is detected, the drive of the feeding conveying means and the platen conveying means is stopped after each of the detected originals has passed, and this feature achieves the above object.

[Effect]

That is, in the automatic document feeder of the present invention, when two or more documents are placed on the document stacking section, the second and subsequent documents are placed on standby at the same time as the previous document is ejected from the exposure section. Since the document is fed from the standby position to the exposure section, the time it takes for the document to be placed on the exposure section is shorter than the distance from the document stacking section to the exposure section. , Therefore, the overall document processing speed becomes faster. Furthermore, if the drive system of the feed conveyance means can be stopped even while the above-platen conveyance means is being driven, the drive system of the feed conveyance means and the above-platen conveyance means may be started, for example, when the first document is fed and when the last document is exposed. As described above, even if the originals are always processed at the same time, including when they are ejected from the unit, the processing speed of the document can be increased, and the configuration of the apparatus can be simplified, and the drive control of the feed conveyance means and the platen conveyance means can be performed simultaneously. It's also easy.

〔Example〕

The present invention will be explained below using illustrated examples.

FIGS. 1 and 2 are a side view of a schematic component and a diagram of a transmission mechanism showing an example of an automatic document feeder according to the present invention.

In the figure, l is a document stacking part, 2 is a pair of left and right parts,
The racks 2A provided at the bottom of each are engaged with the binions 3 rotatably provided on the lower surface of the original stacking section l, sandwiching the binions 3 between them, allowing for symmetrical movement towards and away from the binions 3. 4 is a document size sensor that detects the position of the rack 2A to provide document width information and therefore document size information; 5 is a leading edge position for aligning the leading edges of sheet documents placed on the document stacking section L; regulation plate; 6, document detection means of document stacking section 1; 7, document stacking section 1;
It contacts the top surface of the document placed on the screen and rotates in the direction of the arrow.
It is a friction feed roller that sends out the uppermost document using frictional force, and when the friction feed roller 7 is displaced from the solid line position to the dotted line position by an unillustrated elevating means, the leading edge position regulating plate 5 is also moved by an unillustrated driving means. It is rotated around the support shaft 5A and displaced from the solid line position to the dotted line position so as not to interfere with the feeding of the document.

Reference numeral 8 denotes a sorting and feeding means consisting of light pressure contact between a friction feeding belt 8A rotating in the direction of the arrow and a sorting row 28B stationary or rotating at a slow speed counterclockwise; 9 a pair of pinchers for further feeding the document sent by the sorting and feeding means 8; It is a pressure feed roller,
The conveyance force and conveyance speed of the nipping pressure roller 9 are determined by the friction feed roller 7 and the separation feed speed, as described above, when the document is gripped by the nip feed roller 9, the advancing speed of the document becomes equal to the conveyance speed of the nip feed roller 9. It is larger than means 8. The conveying speed of the pinch feed roller 9 is set so that the friction feed roller 7 and the separating feed means 8 convey the document by a distance Q1 from the regulation position of the leading edge position regulating plate 5 to the gripping position of the roller 9 for pinch feeding. , the speed at which the nipping feed roller 9 conveys the document by a distance of 03 or more from the position where the friction feed roller 7 presses the original to the gripping position of the nip feed roller 9, that is, the conveyance speed of the friction feed roller 7 and the separating and feeding means 8. It is preferable to increase the fold by a factor of Qx/Qr or more. As a result, even if the sorting action of the sorting and feeding means 8 does not work, the pressure contact position of the friction feed roller 7 is retreated from the regulation position of the tip position regulation plate 5, which tends to cause a, -a. .

The overlapping of the document ahead of the length and the next document can be eliminated by the time the next document reaches the pinch feed roller 9, and the feed is now gripped by the pinch feed roller 9 and fed. It is possible to reliably detect a single document by the document detection means IO. When the document detection means IO is provided upstream of the pinch feed roller 9 by a distance ΔQ, the pinch feed is The conveyance speed of the roller 9 is set to (L) of the conveyance speed of the friction feed roller 7 and the separation feed means 8.
-AM) / (Qt -Al1) times [htot6(7
) is preferred. The friction feed roller 7, the separation feed means 8, and the pinch feed roller 9 constitute a feed conveyance means.

Reference numeral 11 denotes a feeding belt which rotates in the direction of the arrow and serves as an above-platen conveyance means for conveying the original received from the feeding conveyance means to the exposure section on the platen glass 12 and for ejecting the original from the exposure section from above the platen glass 12. , llA and II
B is a driving roller and a driven roller on which the feeding belt 11 is stretched; 11C is a tension roller of feeding belt 11;
1D is a pressing roller that brings the feed belt 11 into pressure contact with the upper surface of the platen glass 12.

Immediately before the feed belt 1-11 stops rotating in the direction of the arrow, the feed belt 13 moves to a blocking position where its upper end protrudes above the top surface of the platen glass 12 as shown in the figure to stop the document in the exposure section. an exposure unit stopper whose upper end is displaced to a retracted position retracted below the upper surface of the platen glass 12 to allow passage of the original immediately before the platen glass 12 starts rotating in the direction of the arrow;
Reference numeral 4 indicates means for detecting a document discharged from the platen glass 12 by the feed belt 11, and reference numeral 15 indicates a discharge roller for discharging the document passed through the document detection means 14 onto the document receiving tray 16.

In the example shown in FIG. 2, the feeding and conveying means is driven by the rotation of a motor 17 such as a DC servo motor that drives a motor pulley 17.
A is transmitted to the input pulley 18A of the electromagnetic clutch 18 by the timing belt, and when the electromagnetic clutch 18 is turned on, the rotation of the input pulley 18A is transmitted to the pinch feed roller 9.
and is transmitted to pulley 9A integral with it, and pulley 9
The rotation of A is caused by the timing belt to cause carrier pulley 1
9 and a carrier gear 19A integral therewith;
By meshing with G, the friction feed belt 8A rotates, and the rotation of the roller shaft gear 8AG is transmitted from the roller shaft pulley 8AP, which is integrated with it, to the roller shaft pulley 7A, which is integrated with the friction feed roller 7, by the timing belt. It is done by being given. Further, the platen conveying means and the discharge roller 15 are driven by the rotation of the motor 17 being transferred from the motor pulley 17B to the feed belt 11 by a timing belt.
Drive shaft pulley IIA P integrated with drive roller IIA of
The rotation of the driven roller LLB is transmitted by the timing belt to the roller shaft pulley 15A, which is integral with the discharge roller 15, from the driven shaft pulley IIBP, which is integral with the driven roller LLB. .

The operation of the automatic document feeder configured as described above will be further explained in the case of a copying machine.

A document is placed on the document stacking section l so that the leading edge is regulated by the leading edge position regulating plate 5, the document detecting means 6 detects the presence of the document, and the document is sandwiched between the width position regulating plates 2, whereby the document is When the copy start button is pressed in the automatic document feeding mode where the size sensor 4 detects the document size, the automatic document feeding device operates as follows under the control of the copying machine control device (not shown). works like this.

The friction feed roller 7 is lowered by the elevating means and pressed against the upper surface of the stacked documents, and then the electromagnetic clutch 18 and motor 17 are turned on to rotate the friction feed roller 7 to the discharge roller 15 in the direction of the arrow. As a result, the uppermost document is fed from the document stacking section 1, and when the trailing edge of the document comes off the friction feed roller 7, the next document is fed from the document stacking section 1. The leading edge of the second document has passed the positions of the nipping pressure feed roller 9 and the document detection means 1O, and has not yet reached the position where it receives the conveying force from the feed belt 11, and only one document is being processed. When the leading edge of the first document has not yet reached the position where it contacts the exposure section stopper 13, the electromagnetic clutch 18 is turned off and everything from the friction feed roller 7 to the pressure feed roller 9 is stopped, thereby causing the second document to be exposed. The leading edge of the original is placed on standby at a standby position between the nipping feed roller 9 (in the example of FIG. 1, the original detecting means 1O) and the original gripping position of the feed belt 11. The timing for turning off the electromagnetic clutch 18 is determined based on information on the detection of the leading edges of the first and second documents by the document detection means IO, time measurement or pulse count information from the time of detection, document conveyance speed, and exposure from the document detection means IO. It is determined based on the distance between the contact position of the stopper 13 and the document holding position of the feed belt 1-11, but the standby position is as close as possible to the feed belt l.
It is preferable to decide on the l side in order to increase the overall processing speed.

The motor 17 continues to rotate even after the electromagnetic clutch 18 is turned off, and is turned off to stop the feed belt 11 just before the leading edge of the first document reaches the contact position of the exposure section stopper I3. As a result, the first original document is stopped at the exposure section where the leading edge of the document is brought into contact with the exposure section stopper 13 which was previously moved to the blocking position due to inertial rotation when the feed belt stops. At this time, the turning off timing of the motor 17 is also determined by the detection information of the leading edge of the first document by the document detection means 10, the time measurement or pulse count information from the time of detection, the document conveyance speed, and the timing of the exposure section stopper 13 from the document detection means 10. Determined based on the distance to the contact point.

The exposure optical system consisting of the exposure lamp 20 shown in FIG. 1 emits light onto the first document stopped at the exposure section while moving in the direction of the thick arrow, and forms the document image on a photoreceptor drum (not shown). Scanning exposure for projecting images is repeated a predetermined number of copies.

As a result, a predetermined number of copies of the first original document are obtained.

After completing the scanning exposure for a predetermined number of copies, the first
Without waiting for the return to the position shown, the electromagnetic clutch 18 and the motor 17 are turned on, and the friction feed roller 7 and even the discharge roller 15 rotate in the direction of the arrow again. As a result, the first original in the exposure section passes through the original detection means 14 and is ejected to the original tray 16 by the ejection roller 15, and the second original in the standby position is sent to the feed bell 1-11, and the second original is sent to the feed bell 1-11.
When the trailing edge of the third original comes off the friction feed roller 7, the third original is fed from the original stacking section l. When the third document reaches the standby position, the electromagnetic tarlatch 18 is turned off and the third document is held at the standby position, and then when the second document reaches the exposure section, the motor 17 is turned off. to stop the second original at the exposure section. In this case, as before, the timing for turning off the electromagnetic clutch 18 may be determined based on the time when the document detecting means 10 detects the leading edge of the third document, thereby reducing fluctuations in the standby position. However, in the example of FIG. 1 in which the document detecting means is not provided between the standby position and the feed belt 11, the timing for turning off the motor 17 is determined when the document detecting means 10 detects the trailing edge of the second document. The length of the document must be determined based on the time and the length of the document in the transport direction obtained from the document size information. Therefore, in order to simplify the control, the timing for turning off the motor 17 from the time of the first document is determined based on the time when the document detection means lO detects the trailing edge of the document, or the time when the motor 17 is turned off is determined based on the time when the document detection means lO detects the trailing edge of the document, or It is preferable that a document detecting means is also provided between the belts 11 and the determination is made based on the time when the document detecting means detects the leading edge of the document. In the latter case, care must be taken to ensure that the document conveyance speed is constant before the leading edge of the document reaches the document detection means. Otherwise, the document will not be able to stop stably at the exposure area.

As mentioned above, the second document stopped at the exposure section is scanned and exposed a predetermined number of times in the same way as before, and when that is finished, the electromagnetic clutch 18 and motor 17 are turned on again. Then, the above operation is repeated. When the original detecting means 6 detects that there is no original, the electromagnetic clutch 18 is turned off when the trailing edge of the last original that caused it to be detected is detected by the original detecting means 10, and the last original is also placed in the exposure section. The motor 17 is turned off. When the scanning exposure for the predetermined number of copies of the last document is completed, the electromagnetic clutch 18 is no longer turned on, and only the motor 17 is turned on. As a result, the last manuscript is also placed in the manuscript tray 16.
After the trailing edge of the last document passes the position of the discharge roller 15, the motor 17 is turned off and the series of copying operations in the automatic document feeding mode is completed.

The document detection information of the document detection means 14 is used in combination with information from a timer and pulse counter to detect a jam, detect a failed stop when the document passes the exposure area, count the number of document sheets, etc. .

It goes without saying that the document detection information from the document detection means 10 can also be used for jam detection in combination with information from a timer or pulse counter.

The present invention is not limited to the illustrated example, and the feed conveyance means and the platen conveyance means may be driven by separate motors.

〔Effect of the invention〕

In the automatic document feeder of the present invention, there are two
When more than one original is placed, the time it takes for the second and subsequent originals to be placed on the exposure area is shorter than the distance from the original stacking area to the exposure area for originals whose distance from the standby position to the exposure area is Since the transport time is reduced, the overall document processing speed can be increased, and the configuration and drive control of the apparatus can be simplified.

[Brief explanation of drawings]

FIGS. 1 and 2 are a side view of a schematic component and a diagram of a transmission mechanism showing an example of an automatic document feeder according to the present invention. l...Document stacking section 5...Tip position regulating plate 6.
10.14... Original detection means 7... Friction feed roller 8... Sorting and feeding means 9...
・Pinch feed roller 11...Feed belt 11A...
Drive roller 12... platen glass 13...
Exposure section stopper 15...Discharge roller 16...Document tray 17...Motor 17A, 17B...Motor pulley

Claims (1)

[Claims] A feed conveyance means that sequentially feeds the originals placed on the document stacking section one by one, and an above-platen conveyance means that brings the documents received from the feed conveyance means to an exposure section on a platen glass, leaves them stationary, and then discharges them from the exposure section. In the automatic document feeder, the drive system of the feed conveyance means is configured to be able to be stopped even while the above-platen conveyance means is being driven, and the feed conveyance means feeds the first document from the document placement section. When the document detecting means in the document stacking section detects the presence of a document, the driving is performed at a timing before the second document reaches the platen conveying means and before the first document reaches the exposure section. Then, as long as the document detecting means detects the presence of a document, the document in the standby position is sent to the above-platen conveying means, and the document in the document stacking section is sent to the document stacking section. By repeating the driving of the feeding conveyance means to bring the document to the standby position and the driving of the platen conveyance means which ejects the document from the exposure section and brings the document at the standby position sent from the feed conveyance means to the exposure section, the detection means An automatic document feeder characterized in that, when detecting the absence of a document, the automatic document feeder is controlled so as to stop the drive of the feed conveyance means and the platen conveyance means after each of the detected documents has passed.