JPH0485269A - Both-side document automatic feeder - Google Patents

Abstract

PURPOSE:To improve a processing speed by simultaneously starting discharge conveyance of a leading document and feed conveyance of a following document, placing the following document in temporary standby on a platen, and restarting a feed of the following document to a predetermined position after completion of discharge of the leading document. CONSTITUTION:In the case of setting a following document 40B in a predetermined position A after finishing both side copies of a leading document 40A set to the predetermined position A, motors M2, M3 are placed in a rotational condition to convey the document 40A toward an inverting discharge part 5 by an inverting roller 20 and a conveying belt 16. Simultaneously, the document 40B is conveyed to a platen direction according to a start of rotation of a resist roller 14. A microcomputer 30 temporarily stops the document 40B in a part where its point end reaches a position B before. When a rear end of the document 40A passes through a position of a paper discharge sensor 23, reconveyance of the temporarily stopped document 40B is started. A switching pawl 22 is switched to a reverse feed side. When picture processing of the document, thus reversely fed, is finished, the document is discharged to a paper discharge tray without switching the switching pawl 22 to the reverse feed side. Or the document, after it is again inverted to perform picture processing, is discharged to the paper discharge tray.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a double-sided document automatic feeder that reverses the front and back of a document and conveys the document to a predetermined position on a platen of an image processing device.

[Prior art 1] In an image processing device such as a copying machine or an image processing device, when attempting to efficiently process images written on both sides of a document, the document is turned over as necessary and placed on the platen of the image processing device. An automatic document feeder with a reversing function that automatically feeds documents to a predetermined position is used.

FIG. 4 is a cross-sectional view showing the overall structure of the conveyance mechanism of such an automatic document feeder, and this automatic document feeder 1 includes:
Broadly speaking, there is a feeding unit 3 that feeds the originals on the paper feed tray 2 one by one, a transporting unit 4 that transports the originals fed one by one to a predetermined position on the platen P, and a It consists of a reversing and discharging section 5 that discharges the document, turns it upside down and guides it again to a predetermined position on the platen P, and a # paper tray 6 that loads the discharged document.

The paper feed section 3 includes a pickup roller 7 and an empty sensor 8.
, the separation roller 9 and the registration sensor 10, as well as the pickup roller 7 and the motor M1 as a power source for the separation roller 9. The document placed on the paper feed tray 2 is moved from below by the big 7 pusher roller 7. Several documents are taken out one by one, and only the lowest document is separated by a separating roller 9 and sent to a space 11 having a large loop margin. Here, the document whose direction has been changed along the outer gAff side plate 12 passes through the straight guide section 13 and reaches the two-gamma fold point between the registration roller 14 and the pinch roller 15 of the conveyance section 4 .

The conveyance section 4 includes the registration roller 14 and the pinch roller 15, a wide conveyance belt 16, and the conveyance belt 16.
a driving roller 17 and a driven roller 18 that rotationally drive the
It consists of a plurality of pinch rollers 19 that stretch the conveyor belt 16 over the top surface of the platen P, and a registration roller 14.
The document fed to the entrance of the printer is sent out in the direction of the platen P as the registration roller 14 rotates while being in pressure contact with the registration roller 14 and the pinch roller 15, and starts rotating at the same time as the registration roller 14. It is conveyed onto the platen P by a conveyor belt 16. It should be noted that the registration roller 14 has a Renost clutch G interposed between the conveyance belt 16 and the drive motor M2, so that the rotation of the registration roller 14 is stopped while the conveyance belt 16 is rotating. At this time, the registration sensor 10 remains on until the trailing edge of the document is sent out from the registration sensor 10, so the control section (not shown) starts rotating the registration roller 14 and the drive roller 17, and from the timing the registration sensor 10 is activated by the passage of the trailing edge of the document. The number of pulses applied to the motor M2, which is the power source for the drive roller 17 and the registration roller 14, is counted during the open period until the timing when the register roller 14 is turned off, and the document size L1 is classified into regular document sizes based on the count value. Then, when a number of pulses corresponding to the distance 10 from the position of the registration sensor 10 to a predetermined position A on the platen P are applied to the motor M2 when only one side is copied, the motor M2 is stopped at one point.

As a result, the original is set at a predetermined position j[A on the platen P.

Next, anti-Tll1. # The output section 5 includes a reversing roller 20, driven rollers 21a and 21b pressed against the reversing roller 20, and a switching claw 2 that transports the document reversely in the direction of the conveyor belt 16 with the front and back sides of the document reversed.
2. Paper discharge sensor 23, sensor 24 for determining the stop timing during reverse feeding, paper discharge row 725, reversal a-22
When the image processing for one side of the document is completed, the Ni document is conveyed in the discharge direction by the conveyor belt 16, and the document is conveyed in the discharge direction by the reversing roller 20. At this time, if the switching claw 22 is as shown in the figure, the document is ejected to the ejection tray 6 by the ejection roller 25. However, when the switching claw 22 is switched to the reverse feed side, the sheet is guided toward the driven roller 181III of the conveyor belt 16, and is set at a predetermined position on the platen P again by the reverse rotation of the conveyor belt 16.

On the other hand, during double-sided copying, in order to align the ejection order of the originals, the originals are passed over the platen P and reversed from front to back at the reversing discharge section 5, and the reversed originals are transferred to the platen P.
One-sided copying is performed by setting the printer at the predetermined position A. After that, the original is turned over in the reversing and discharging section 5 and set again at the predetermined position A, and the remaining one side is copied.
Thereafter, the switching claw 22 of the reversing and discharging unit 5 is switched to the illustrated state, and the paper is discharged onto the paper discharge tray 6.

The problem is the control method when ejecting the preceding original and feeding the next succeeding original in the unit. Conventionally, the following methods have been broadly classified.

(1) When the leading edge of the preceding document is detected by the paper ejection sensor 23, by setting the time opening t corresponding to the size of the preceding document in the timer α, and turning on the registration clutch G after the time 11. , how to start feeding subsequent documents.

(2) A method of setting time 1 according to the maximum size original in the method (1) above, and starting feeding the subsequent original after the elapse of time.

(3) A method in which feeding of the subsequent document is started when the trailing edge of the preceding document is detected by the paper ejection sensor 23.

[Problems to be Solved by the Invention] However, in the control methods (1) to (3) above, in the control method (1), it is necessary to set the time t in the timer for each size of the preceding document; There is a problem that control processing becomes troublesome. Furthermore, the conveyor belt 16 must be continuously rotated from the time it starts discharging the preceding document until the time when the subsequent document is set at a predetermined position. For this reason, there is a problem in that the noise accompanying the rotation of the conveyor belt 16 cannot be ignored, and the wear increases.

On the other hand, the control methods (2) and (3) have the problem that the waiting time until the start of feeding of the subsequent original is long, there is a lot of wasted time during feeding, and the processing speed is reduced.

The present invention was made to solve these problems, and it simplifies the control process associated with document ejection and feeding.
It is another object of the present invention to provide a double-sided document automatic feeding device that can suppress noise and wear in the conveyance system, and can also improve processing speed.

[Means for Solving the Problems 1] In order to achieve the above object, the double-sided automatic feeding device of the present invention includes a conveyor belt that conveys the document to a predetermined position on the platen, and a conveyor belt that conveys the document to a predetermined position on the platen, and a reversing roller that reverses the document conveyed in the discharge direction by the conveyor belt and guides it toward the discharge port or the predetermined position by reversing the front and back sides; and a reversing roller that conveys the preceding document to be conveyed in the discharge direction by the conveyance belt and conveys it to the predetermined position. control means for simultaneously starting conveyance of a subsequent document to be transferred, and for conveying the subsequent document to a predetermined position by the reversing roller and the conveyance belt after the document is temporarily stopped on the platen until the preceding document is ejected; It was composed of

[Function 1] In the above configuration, the ejection conveyance of the preceding document and the feeding and conveyance of the succeeding document are started at the same time, so that the rotation time of the conveyor belt is shortened by the amount necessary for ejecting the preceding document. Therefore, noise and wear associated with the rotation of the conveyor belt are also reduced.

Further, since the feeding of the temporarily stopped subsequent document to a predetermined position is restarted when the preceding document is ejected, it becomes unnecessary to set a timer time according to the size of the preceding document. Furthermore, when the preceding original is ejected, the subsequent original is fed, but since the subsequent original is already located on the platen, there is no wasted time to set it in the designated position, and the original is ejected efficiently. and feeding can be carried out.

[Example 1 Hereinafter, the present invention will be explained in detail based on examples.

FIG. 1 is a structural diagram showing the principle of the conveyance mechanism according to the present invention, and is constructed in the same manner as in FIG. 4, and the same parts are indicated by the same symbols.

FIG. 2 is a block diagram showing the configuration of a control section that controls the conveyance of a document in the present invention. This control section is specifically constituted by a microcomputer 30.

This microcomputer 30 controls the conveyance of the document in cooperation with each element of the conveyance mechanism configured in the same manner as shown in FIG. Therefore, the configuration and operation will be explained below with reference to each figure.

In FIG. 2, the microcomputer 30 includes an empty sensor 8, a registration sensor 10, and a discharge sensor 23.
In addition to inputting each sensor output signal of the sensor 24 for detecting stop timing, there is also a clock pulse Φ1 that serves as a reference for the pulses PMI to PM3 applied to the motors M1 to M3.
．． Φ2 is input. Further, the output signals include a motor M1 for rotating the separation roller 9, etc. of the paper feed section 3;
Application hull XP to motor M2 for rotating the conveyor belt 16 and motor M3 for rotating the reversing roller 20
M1 to PM3, an on signal RCL to the registration clutch G for transmitting the rotation of the motor M2 to the registration roller 14, a drive signal SD to the slide/id (not shown) for switching the switching pawl 25, etc. are output. has been done.

Further, inside the microcomputer 30, four timers T, -T4 and one counter CT are provided.

FIGS. 3 and 4 are 70-charts showing the procedure for discharging the preceding original and feeding the succeeding original.

The operation of the embodiment will be described below with reference to this 70-chart.

First, double-sided copying of the preceding original 40A, which was set at a predetermined position A on the platen P shown in Figures IJ&1, is completed.
Next, considering the case where the succeeding original 40B is set at the predetermined position 140A, first, the motors M 2 and M 3 are started, and the registration clutch G is turned on (step 81). As a result, the motors M 2 and M 3 become in a rotating state, and the reversing a-220 and the conveyor belt 16
begins to rotate in the direction to eject the preceding original 40A, and the preceding original 40A is conveyed by the conveying belt 16 toward the reversing and ejecting section 5. At the same time, the subsequent document 40B located at the registration roller 14 is moved to the registration roller 1.
4 is conveyed in the direction of the platen.

After turning on the registration clutch G, the microcomputer 30 moves the subsequent document 40B to a position B in front of the reversing and discharging section 5.
In order to temporarily stop the rotation, a timer time t1 corresponding to the time required to reach the front position B is set in the inversion front stop timer T1 (step S2).

On the other hand, when the leading edge of the preceding layer N40A being conveyed in the discharge direction passes the position of the paper discharge sensor 23, the paper discharge sensor 23
Since the output signal of microcomputer 3 turns on,
0 sets the deceleration timer T2 to the deceleration time t2, which determines the time to decelerate the motor M3 that drives the reversing a-ra 20 (step S4).

Then, when the reversal front stop timer T1 times up, the leading edge of the succeeding document 40B should have reached the front position B, so the motor M2 that drives the conveyor belt 16 is stopped (step 35.S6). Subsequent manuscript 4
0B temporarily stops when its tip reaches the front position B.

On the other hand, the motor M3 is rotating at high speed and the preceding document 40A is being ejected by the reversing roller 20, but in step S4
When the deceleration timer T2 set in step 1 times up, the microcomputer 30 decelerates the motor M3 (step S8). As a result, the succeeding document 40B is conveyed in the discharge direction at a low speed immediately after the leading edge thereof passes the paper discharge sensor 23. The reason for switching to low-speed transport in this way is to prevent the originals ejected to the paper ejection tray from being uneven. When the output signal of the paper ejection sensor 23 turns off, the microcomputer 30 ejects the paper for a timer time T, which corresponds to the time required until the trailing edge of the preceding document 40A is ejected to the paper ejection tray. Set the completion timer T3 and wait for the timer T3 to time up. If the timer t expires after 13 hours (step 511), it means that the preceding document 40A has been completely ejected to the paper ejection tray, so the motor M2 is started and the motor M3 is driven at high speed. (Step 512
). As a result, the subsequent document 40B, which had been temporarily stopped at a position in front of the reversing and discharging section 5, starts to be conveyed again. Therefore, when the leading edge of the subsequent document 40B reaches the position of the paper discharge sensor 23 and the paper discharge sensor 23 is turned on, the microcomputer 30 starts counting the pulses applied to the motor M3. (813,514). In this state, the conveyance of the document is completely controlled by the rotation of motor M3, so
In the next step 315, motor M2 is stopped. At the same time, the switching claw 22 is switched to the reverse feed side. During this time, the subsequent document 40B is being conveyed by the reversing roller 20 toward the switching pawl 22, but as the switching pawl 22 is switched to the reverse feeding side, the driven roller 18 of the conveying belt 16
111 toward the rear end. Therefore, this end 1
In order to turn the conveyor belt 16 into a reverse feeding state in anticipation of the leading edge of the document reaching position 8, a reversal timer T of the motor M2 is set, and when the timer T4 times out, the reversal of the motor M2 is set. , the conveyor belt 16
is in the reverse feeding state.

(S16.S17.S1B).

When the trailing edge of the trailing original 40B reaches a position where it passes the driven roller 21b, it becomes controlled by the rotation of the conveyor belt 16, so the sensor 24 turns on and detects a part of the trailing manuscript 40B that is being fed backwards. and the paper ejection sensor 23 is t.
& When the rear end of the subsequent document 40B is detected and turned off, counting of the number of pulses applied to the motor M3 is stopped. (S
19. S20.521), thereby the subsequent document 40B
The sine rL1 is detected in a form converted into the number of pulses applied to the motor M3 (S 22 ).

Next, the size L1 of the subsequent document 40B detected in this way is converted into the number of pulses applied to the motor M2 (S2
3). After this, the sensor 24 and a predetermined position A on the platen are
The number of pulses applied to the motor M2 corresponding to the distance L2 from
25). That is, the difference between the distance L2 to the predetermined position A and the document size L1 is determined. Next, when the rear end of the succeeding document 40B passes the position of the sensor 24 and the sensor 24 is turned off, the motor M2 is stopped (826, 527). After this, when the number of pulses corresponding to the difference L2-Ll is applied to the motor M2, the motor M2 is stopped (8
2B, 529).

When the image processing of the document sent backward in this manner is completed, the document is ejected to the paper ejection tray without switching the switching claw 22 to the reverse feed side. Alternatively, the paper is reversed again, subjected to image processing, and then ejected to the paper ejection tray. In this case, when reruminating, the document size is L.
1 is not detected, and the document is set at a predetermined position based on the value of document size L1 detected during the first rumination.

As described above, in this embodiment, the ejection conveyance of the preceding original document 40A and the feeding conveyance of the succeeding original document g40B are started at the same time, and the subsequent original document 40B is temporarily held on the platen until the output of the preceding original document 40Af)@ is completed. After the ejection of the preceding document 40A is completed, feeding to the predetermined position A is restarted. That is, by reusing a part of the ejection operation of the preceding original 40A, the subsequent original f
I am trying to feed g40B. Therefore, the rotation time of the conveyor belt is shortened by the time equivalent to the ejection time of the preceding document 40A, and the conveyor belt 1 when ejecting and feeding the document is
6. Noise and wear can be reduced. Furthermore, since the feeding of the temporarily stopped subsequent document 40B to the predetermined position A is restarted when the preceding document 40A is ejected, it is no longer necessary to set a timer time according to the size of the preceding document 40A. Become. Furthermore, since the preceding original 40A has been ejected, the subsequent original 40B is fed, but the subsequent original 40B
Since it is already located on the platen, there is no wasted time until it is set in a predetermined position, and the document can be ejected and fed efficiently. Furthermore, subsequent manuscript 40A
Since the document is temporarily stopped on the platen, even if the preceding document 40A is ejected at a low speed, accidents such as colliding with it and causing a conveyance abnormality in both can be prevented. In the invention, the ejection and transportation of the preceding original and the feeding and transport of the subsequent original are started simultaneously, and the subsequent original is temporarily held on the platen until the ejection of the preceding original is completed.
After the ejection of the preceding original is completed, feeding to the predetermined position fA is restarted. That is, part of the ejection operation of the preceding original is used to feed the succeeding original. Therefore, the rotation time of the conveyor belt is shortened by the time equivalent to the ejection time of the preceding document, and the noise and wear of the conveyor belt during ejection and feeding of the document can be reduced.

Further, since the feeding of the temporarily stopped subsequent document to a predetermined position is restarted when the preceding document is ejected, it becomes unnecessary to set a timer time according to the size of the preceding document. Furthermore, when the preceding original is ejected, the subsequent original is fed, but since the subsequent original is already located on the platen, there is no wasted time to set it in the designated position, and the original is ejected efficiently. and feeding can be carried out.

Furthermore, in order to temporarily stop the subsequent document on the platen,
Even if the preceding document is ejected at a low speed, accidents such as colliding with the preceding document and causing a conveyance abnormality in both can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a principle explanatory diagram for explaining the present invention in detail, Fig. 2 is a block diagram showing an embodiment of the control section, and Figs. 3 and 4 show the paper ejection operation and paper feeding operation of the control section. The flowchart shown in FIG. 5 is a sectional view showing the overall configuration of a mechanism for transporting a document.

Claims (1)

[Claims] a conveyance belt that conveys the document to a predetermined position on the platen; and a reversing roller that reverses the document conveyed in the discharge direction by the conveyance belt and guides it to the discharge port or to the predetermined position after image processing is completed. and the conveyance of the preceding document to be conveyed in the discharge direction by the conveyor belt and the conveyance of the subsequent document to be conveyed to the predetermined position are simultaneously started, and the subsequent document is discharged from the preceding document. A double-sided automatic document feeder comprising: a control means for temporarily stopping the document on the platen until the end of the document, and then conveying the document to a predetermined position by the reversing roller and the conveyor belt.