JPH05188689A - Automatic document feeder - Google Patents

Abstract

PURPOSE:To provide an automatic document feeder where a document can be extracted without load on the document applied by a document stopper and without damaging the document even when a power source is turned off in case of jamming of the document. CONSTITUTION:The document stopper 41 for positioning the front end of the document P at the time of setting the document P on a document placing table 20 is supported in such a manner that it can freely move between the document front end aligning position and the document feeding position which is out of a document carrying path. The position of the document stopper 41 is switched by a self-hold type solenoid 44 with a permanent magnet. When the self-hold type solenoid 44 comes to the state of self-holding, the document stopper 41 is held in the document feeding position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder.

[0002]

10 and 11 show the vicinity of a paper feed port of a conventional automatic document feeder. A paper feed roller 101 and a pair of separation rollers 102 and 103 are provided near the paper feed port of the automatic document feeder. Paper feed roller 10
1 and the pair of separating rollers 102 and 103 are driven by a sheet feeding motor (not shown). As is well known, the pair of separating rollers 102 and 103 includes a forward rotation roller 103 that rotates in the document feeding direction and a reverse rotation roller 102 that rotates in the direction opposite to the document feeding direction, and prevents double feeding of the documents. To do.

Further, in the vicinity of the paper feed port, the document placing table 104 is provided.
A document stopper 110 for positioning the leading edge of the document when setting the document P on the document is provided. The document stopper 110 is swingably provided around one end Q thereof. The document stopper 110 is always shown in FIG.
As shown in FIG. 7, the urging force of a spring (not shown) causes the positioning plate portion 111 on the swinging end side to come to a position where it blocks the document conveying path between the sheet feeding roller 101 and the pair of separating rollers 102 and 103. Held in. Then, at the time of feeding the original, as shown in FIG. 11, until the positioning plate portion 111 is positioned below the original feeding path between the feeding roller 101 and the pair of separating rollers 102 and 103 by a solenoid (not shown). It is rocked and held.

The paper feed roller 101 is supported so as to be movable up and down, and is located at the upper position shown in FIG. 10 when the original P is set on the original placing table 104, and the original P is placed on the original placing table 104. When placed, the front end of the document P in the document transport direction is in contact with the positioning plate portion 111 of the document stopper 110. When the original is fed, the feeding roller 101 is arranged as shown in FIG.
As shown in FIG. 1, the sheet is moved to the lower position, and the sheet can be fed.

[0005]

A solenoid for switching the position of the document stopper 110 is energized from the start of document feeding until there are no documents on the document table 104, and the document stopper 110 is shown in FIG. Held in position. However, generally, when a document jam occurs during the paper feeding operation, the driving of the solenoid is stopped and the document stopper 110 is returned to the original position shown in FIG. Although some solenoids do not control the drive of the solenoid to stop when a document jam occurs (see, for example, Japanese Patent Laid-Open No. 61-64650), the power source of the copying machine main body is turned off when a document jam occurs. Then, the driving of the solenoid is stopped, and the document stopper 110 is returned to the original position shown in FIG.

Paper feed roller 101 and separation roller pair 10
A document jam occurs in a state where the document straddles 2 and 103, and based on this document jam, the document stopper 11
When 0 is returned to the position shown in FIG. 10, the document stopper 11
0 puts a load on the document. Therefore, when pulling out the original from the paper feed port, there is a problem that an extra load is applied to make it difficult to pull out and the original is damaged. Such a problem also occurs when the power of the copying machine is inadvertently turned off during the document feeding operation.

The present invention provides an automatic document feeder which can pull out a document without damaging the document even if the power is turned off when a document jam occurs and the document is not loaded by the document stopper. The purpose is to

[0008]

In the automatic document feeder according to the present invention, a document stopper for positioning the leading end of the document when setting the document on the document table is provided with a document leading end position and a document conveying position. It is movably supported between a document feeding position that is out of the path, and the position of the document stopper is switched by a self-holding solenoid having a permanent magnet, and the self-holding solenoid is in a self-holding state. The above-mentioned document stopper is held at the document feeding position when the document is opened.

A document detector is provided near the document feed port,
When a document jam occurs, when the document is no longer detected by the document detector, it is preferable to release the self-holding state of the self-holding solenoid and switch the document stopper to the document leading end position. ..

In an automatic document feeder having an openable and closable cover for covering the paper feed roller and the separating roller pair, and one roller of the separating roller pair is attached to the cover, when a document jam occurs. In the above, when the cover is opened, the self-holding state of the self-holding solenoid may be released to switch the document stopper to the document leading edge positioning position.

[0011]

In the automatic document feeder according to the present invention, the document stopper for positioning the leading edge of the document when the document is set on the document placing table is provided for feeding the document out of the document leading edge positioning position and the document transport path. It is movably supported to and from the position. Then, the position of the document stopper is switched by a self-holding solenoid having a permanent magnet,
When the self-holding solenoid is in the self-holding state, the document stopper is held at the document feeding position.

Therefore, even if the power is turned off when a document jam occurs, the document stopper is held at the document feeding position and does not move to the document leading edge positioning position, so that the jammed document is not loaded by the document stopper. It will not take. Therefore, the jammed document can be smoothly pulled out without damaging the document.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an automatic document feeder used in a copying machine will be described below with reference to the drawings.

FIG. 1 shows the structure of an automatic document feeder.

The automatic document feeder 1 is installed on the upper surface of the copying machine main body 2. The automatic document feeder 1 includes a paper feed roller 21 and a pair of separating rollers 22 and 23 for taking in the original P on the original placing table 20, and a pair of registration rollers 24 and 25 for conveying the taken original at a predetermined timing.
And a conveying belt 26 that conveys the original conveyed by the pair of registration rollers 24 and 25 to a predetermined reading position on the contact glass 3 of the copying machine main body 2 and conveys the read original to the discharged original stock unit 27. It has and. In the automatic document feeder 1, originals P are placed on the original placing table 20 with the original surface facing upward, and the originals P on the lower side are fed in order.

Paper feed roller 21, pair of separation rollers 22, 2
3 and the pair of registration rollers 24 and 25 are the paper feed motor 3
Driven by 1. The pair of separating rollers 22, 23 are
As is well known, it is composed of a forward rotation roller 22 that rotates in the document feeding direction and a reverse rotation roller 23 that rotates in the direction opposite to the document feeding direction, and prevents double feeding of documents. The reverse rotation roller 23 includes a paper feed roller 21 and a separation roller pair 2.
It is attached to the paper feed unit cover 11 that covers the sheets 2 and 23. The paper feed unit cover 11 is pivotally attached to the main body of the automatic document feeder via a pin 12 and is openable and closable about the pin 12. Also, the automatic document feeder 1
The main body cover 13 can also be opened and closed.

Paper feed roller 21 and separation roller pair 2
2 and 23, a paper feed clutch 32 not shown in FIG.
The rotational force of the sheet feeding motor 31 is transmitted via (see FIG. 2). The rotational force of the sheet feeding motor 26 is transmitted to one of the pair of registration rollers 24 and 25 via a registration clutch 33 (see FIG. 2) not shown in FIG.

A document stopper 41 for positioning the leading edge of the document when setting the document on the document table 20 is provided near the document inlet. Document stopper 4
1 is swingably provided about one end Q thereof. In the document stopper 41, the locating plate portion 42 on the swinging end side of the document stopper 41 is always driven by the urging force of the spring 43.
It is held so as to come to a position where it blocks the document transport path between 1 and the pair of separating rollers 22 and 23. Hereinafter, this state position is referred to as a document leading edge positioning position. Then, at the time of feeding the original, the positioning plate portion 4 is moved by the solenoid 44.
The sheet 2 is rocked and held until it comes to a position below the document conveying path between the sheet feeding roller 21 and the pair of separating rollers 22 and 23. Hereinafter, this state position is referred to as a document feeding position. When the document stopper 41 is in the position for positioning the leading edge of the document, when the document is placed on the document table 20, the front end of the document in the document transport direction is positioned by the positioning plate portion 42 of the document stopper 41.
Is in contact with.

As the solenoid 44, there is used a self-holding solenoid having a permanent magnet for attracting and holding the actuating shaft at the attracting position, and performing attracting and returning operations by pulse energization. As such a self-holding solenoid, for example, model number JSM manufactured by Hoshidenki Seisakusho Co., Ltd.
0118 may be mentioned. The solenoid 44 is normally in a state in which its operating shaft is advanced, and in this case, the document stopper 41 is at the document leading edge positioning position. In this state, when a pulse for attracting the operating shaft to the solenoid 44 is applied (suction driving), the operating shaft retracts and is attracted to the permanent magnet, and the operating shaft is held at the retracted position. When the operation shaft of the solenoid 44 retracts, the document stopper 41 swings to the document feed position. After the operating shaft of the solenoid 44 retracts and is attracted to the permanent magnet,
The adsorption state is maintained even without energization. When the operating shaft is held at the retracted position and when the operating shaft is returned to the original advanced position, a pulse for returning the operating shaft to the solenoid 44 is applied (return drive).

On the rear side of the paper feed roller 21 in the original conveying direction,
A first document detector 51 for detecting a document on the document table 20 is provided. Further, the automatic document feeder 1 is provided with a paper feed unit cover open / close detector 52 for detecting the open / closed state of the paper feed unit cover 11. Further, second and third document detectors 53 and 54 are provided on the rear side and the front side of the pair of registration rollers 24 and 25 in the document conveying direction.

The conveyor belt 26 is driven to travel by the conveyor motor 34. The automatic document feeder 1 is provided with a rotation amount detector 55 for detecting the rotation amount of the conveyance motor 34 and a main body cover open / close detector 56 for detecting the open / closed state of the automatic document feeder main body cover 13. Has been.
The rotation amount detector 55 outputs a pulse each time the carry motor 34 rotates by a predetermined rotation angle. Near the document exit,
A fourth document detector 57 is provided.

FIG. 2 shows the electrical construction of the automatic document feeder and the main body of the copying machine.

The automatic document feeder 1 is controlled by the feeder controller 60. The feeding device side control unit 60 is C
It is provided with a PU 61, a ROM 62 for storing its programs and the like, a RAM 63 for storing necessary data, an input interface 64 and an output interface 65.

First original detector 51, second original detector 5
The third, third document detector 54, fourth document detector 57, paper feed unit cover open / closed detector 52, main body cover open / closed detector 56, and rotation amount detector 55 are connected to the CPU 61 via an input interface 64. There is. Paper feed motor 31, transport motor 34, paper feed clutch 32, registration clutch 3
3, the solenoid 44 is connected to the CPU 61 via the output interface 65.

Further, the copying machine main body side control unit 70 is connected to the CPU 61 via an input interface 64 and an output interface 65. A display unit 71, an operation unit 72 having a print key and the like, and a memory 73 are connected to the copying machine main body side control unit 70.

FIG. 3 shows the overall processing procedure by the CPU 61.

When the power is turned on, it is determined whether or not the paper feed unit cover 11 is closed based on the paper feed unit cover open / close detector 56 (step 1). Paper feed unit cover 11
If is open, the solenoid 44 is driven to return for a predetermined time, for example, 500 msec (step 3) to prepare for the document set, and the process proceeds to step 5. When the solenoid 44 is driven to return, the solenoid 44
The operating shaft of the document advances, and the document stopper 41 is positioned at the document leading edge positioning position.

When the paper feed unit cover 11 is closed,
It is determined whether or not the original is detected by the first original detector 51 (step 2). Even when the original is not detected by the first original detector 51, in order to prepare for the original set, the solenoid 44 is operated for a predetermined time, eg, 5
The return drive is performed for 00 msec (step 3), and the process proceeds to step 5. When the solenoid 44 is driven to return, the document stopper 41 is positioned at the document leading edge positioning position.

In the step 2, when the first document detector 51 detects the document, it is considered that the document jam has occurred when the power of the copying machine main body is turned off, and the jam flag FJ is set. It is set (FJ = 1) (step 4), and the process proceeds to step 5.

In step 5, the jam flag FJ
Is set (step 5). The jam flag FJ is reset in the initial setting performed when the power is turned on. Then, as described above, when the power supply is turned on, the paper feed unit cover 11 is closed and the original is detected by the first original detector 51, or the automatic original feeding process (step 6) described later is executed. If a document jam has occurred, it is set.

If the jam flag FJ is not set in step 5, the automatic document feeding process is executed (step 6). When the jam flag FJ is set, the return control process of the document stopper 41 is executed (step 7).

FIG. 4 and FIG. 5 show the automatic document feeding processing procedure of step 6 described above.

Whether or not the paper feed unit cover 11 is closed (step 101), the automatic document feeder main body cover 13 is provided.
Is closed (step 102) and whether a document is set on the document table 20 (step 103) depending on whether the paper feed unit cover open / close detector 52, the main body cover open / close detector 56, and the first cover are opened. It is checked based on the document detector 51. When the paper feed unit cover 11 and the transport unit cover 13 are closed and a document is set on the document table 20, when the print key of the operation unit 72 of the copying machine body is turned on (step 10).
4) The solenoid 44 is suction driven for a predetermined time (step 105), the operating shaft of the solenoid 44 retracts and is attracted to the permanent magnet, and the retracted state is maintained even after the suction drive is stopped. As a result, the document stopper 41 swings and is moved to and held at the document feeding position.

After that, the primary paper feeding process is executed (step 106). In the primary paper feeding process, as shown in FIG. 6, first, the paper feeding motor 31 is driven and the paper feeding clutch 32 is engaged (steps 131 and 132),
The paper feed roller 21 and the pair of separating rollers 22 and 23 are driven. As a result, the lowermost one of the documents stacked and placed on the document table 20 is taken into the automatic document feeding process 1.

Then, when the front end of the original in the conveying direction is detected by the second original detector 53 located behind the pair of registration rollers 24 and 25 in the original conveying direction (step 133), time counting for a predetermined time is started (step). 134). For this predetermined time, the front edge of the original is detected by the second original detector 53, and then the front edge of the original is paired with the registration rollers 24 and 25.
Therefore, the front end of the document is set to a time suitable for forming a proper loop. When the predetermined time has elapsed (step 135), the registration clutch 33 is engaged (step 136), and the registration roller pair 24, 25 is driven.

The front end of the original is the registration roller pair 2
The third document detector 54 located at the front of the document transport direction of Nos. 4 and 25
When detected by (step 137), it is determined whether or not the first flag F1 is set (step 138). The first flag F1 is for storing whether or not the original document that is being primary-fed is the first original document among the original documents set on the original document table 20, and is initialized after the power is turned on. Or at the end of the automatic document feeding process.

Therefore, in the primary paper feed processing in step 106, the first flag F1 is in the reset state (F1 = 0), so the routine proceeds to step 139, where the first flag F1 is set (F1 = 1). After being
The paper feed clutch 32 is disengaged (step 141). As a result, the primary sheet feeding process for the first sheet ends. Since it is the first original, the registration clutch 33 is kept in the engaged state even after the front edge of the original is detected by the third original detector 54, and the original is sent to the conveyance belt 26 side.

When the primary sheet feeding process is completed, the secondary sheet feeding process is executed (step 107). In the secondary paper feeding process, as shown in FIG. 7, first, the registration clutch 33 is engaged and the carry motor 34 is driven (steps 151, 152). As a result, the pair of registration rollers 24 and 25 are driven and the transport belt 26 is driven to travel. As mentioned above, step 106.
In the primary paper feeding process in, the registration clutch 3
Since 3 is still entered, step 106
In the secondary paper feeding process performed after the above, the registration roller pairs 24 and 25 are driven from the beginning.

The pair of registration rollers 24 and 25 sends the original to the side of the conveying belt 26, and the conveying belt 26 conveys the original toward a predetermined reading position on the contact glass 3. The trailing edge of the document is the third document detector 54.
When detected by (step 153), the counting of the output pulse number of the rotation amount detector 55 is started to position the document at the reading position on the contact glass 3 (step 154). Further, the registration clutch 33 is disengaged and the driving of the paper feed motor 31 is stopped (step 1
55, 156), the secondary sheet feeding process this time is ended.

When the count value of the number of output pulses of the rotation amount detector 55 reaches a predetermined value after the secondary paper feeding process is completed (step 108), the driving of the carry motor 34 is stopped (step 109). As a result, the document is positioned at the reading position on the contact glass 3. Further, a print signal (PRINT signal) is sent to the copying machine main body side control portion 70 to notify the copying machine main body control portion 70 that the original has been set at the reading position (step 110). The copying machine main body side control unit 70 starts the exposure process based on the print signal.

After the print signal is output, it is checked based on the first document detector 51 whether or not the document remains on the document table 20 (step 111). If the original remains, the primary paper feeding process shown in FIG. 6 is executed again to feed the next original (step 112). In the primary sheet feeding process for the second and subsequent sheets, the first flag F1 has already been set (F1 = 1), so step 138
Is YES. Therefore, when the front edge of the original is detected by the third original detector 54 in step 137, the process proceeds from step 138 to step 140, and the registration clutch 3 is used to set the timing for exchanging the original to be read.
3 is cut. That is, with the front end of the original document positioned at a predetermined position in front of the registration roller pair 24, 25 in the original conveyance direction, the original document is placed in a standby state, and the primary paper feeding process ends. In this case, the original document is in a state of being pinched by the pair of registration rollers 24 and 25.

When the primary paper feeding process is completed, the second flag F2 is set (F2 = 1) (step 113),
The driving of the paper feeding motor 31 is stopped (step 11).
5). After this, when a document exchange signal (CHANGE signal) is sent from the copying machine main body side control unit 70 (step 1).
16), it is checked whether the second flag F2 is set or reset (step 117). If the second flag F2 is set, it is determined that the document is primarily fed and is in the standby state, and the feeding motor 31 is driven (step 118).

Then, in step 107, the secondary paper feeding process shown in FIG. 7 is executed again. In the secondary sheet feeding process for the second and subsequent sheets, the pair of registration rollers 24 and 25 and the transport belt 26 are driven, so that the original document that has been waiting by the primary sheet feed is transported toward the reading position at the same time. The document that has already been read is discharged to the discharged document stock unit 27. When the secondary sheet feeding process is completed and the count value of the output pulse number of the rotation amount detector 55 reaches a predetermined value (step 108), the driving of the carry motor 34 is stopped (step 109), and the print signal is transmitted to the copying machine. Main body side control unit 7
0 (step 110).

In this way, when all the originals set on the original placing table 11 have been subjected to the primary and secondary paper feeding, the originals are no longer detected by the first original detector 51, so that step 111 At document placement table 2
It is determined that there is no document left on 0. In this case, the process proceeds from step 111 to step 114, and the second flag F2 is reset (F2 = 0). Then, the driving of the paper feed motor 31 is stopped (step 115).

After this, when a document replacement signal is sent from the main body controller 70 of the copying machine (step 116), the state of the second flag F2 is determined (step 117). Second
Since the flag F2 is in the reset state, the routine proceeds from step 117 to step 119, and the carry motor 34 is driven to eject the last document at the reading position. When the trailing edge of the last document is detected by the fourth document detector 57 (step 120), the driving of the carry motor 34 is stopped (step 121). Further, the solenoid 44 is driven to return for a predetermined time (step 12
2) The attraction state of the working shaft to the permanent magnet is released, and the working shaft advances. As a result, the document stopper 41 swings and is moved to and held at the document leading edge positioning position. Further, the first flag F1 is reset (step 123), the automatic document feeding process this time is ended, and the process returns to step 5.

8 and 9 show the document stopper return control processing procedure in step 7 described above.

When a document jam occurs, the user usually opens the paper feed unit cover 11 or the main body cover 13 to remove the jammed document. When the document jam occurs as described above, the jam flag FJ is set, the automatic document feeding process is stopped, and the jam flag FJ is set.
The automatic document feeding process is not performed unless is reset. In this automatic document feeder 1, as can be seen from the document stopper return control process described below, the paper feed unit cover 11 or the main body cover 13 must be opened in order to reset the jam flag FJ once set. Is one of the necessary conditions. Therefore, when a jam occurs, the paper feed unit cover 11 and the main body cover 1
Even when the jam original can be removed without opening 3, the user needs to once open the paper feed unit cover 11 or the main body cover 13 in order to reset the jam flag FJ.

In the document stopper return control process, first, it is determined whether or not the paper feed unit cover 11 is opened based on the paper feed unit cover open / close detector 52 (step 16).
1). When the paper feed unit cover 11 is opened, the open flag FO is set (FO = 1) (step 162).
In order to prepare for the original set after clearing the jam, the solenoid 44 is driven to return for a predetermined time (step 16).
3) The document stopper 41 is positioned at the document leading edge positioning position.

The reason why the document stopper 41 is positioned at the document leading edge positioning position when the paper feed unit cover 11 is opened is as follows. That is, even if the document exists on the paper feed roller 21 and the pair of separation rollers 22 and 23 when the jam occurs, the paper feed unit cover 1
When 1 is opened, the reverse rotation roller 23 of the pair of separating rollers 22 and 23 is separated from the forward rotation roller 22 as shown by the chain line in FIG. 1, so that even if the document stopper 41 is moved to the document leading edge positioning position, the jammed document is not scanned. This is because the document stopper 41 is not loaded.

When the processing of step 163 is performed or when the paper feed unit cover 11 is not opened, it is determined whether the body cover 13 is opened or not based on the body cover open / close detector 56 (step). 164). When the main body cover 13 is opened, the open flag FO is set (FO = 1) (step 165).

When the process of step 165 is performed or the main body cover 13 is not opened, the first
It is determined whether or not the document is no longer detected by the document detector 51 (step 166). First document detector 5
When the document is no longer detected by 1, the paper feed roller 21 and the separation roller pair 24, 2 when a jam occurs
Whether the manuscript did not exist across 5 and
Alternatively, it is determined that the original was present in the state where the original straddled the paper feed roller 21 and the pair of separating rollers 24 and 25 but was removed, and the reset flag FR is set (FR = 1).
(Step 167). Further, since the document does not exist in the state where it straddles the paper feed roller 21 and the pair of separating rollers 24 and 25, the solenoid 44 is driven to return for a predetermined time in order to prepare for the document set after the jam is released (step 168). ), The document stopper 41 is positioned at the document leading edge positioning position.

When the process of step 168 is performed or the document is detected by the first document detector 51, it is determined whether the open flag FO is set (step 169). If the open flag FO is not set, that is, if neither the paper feed cover 11 nor the main body cover 13 has been opened after the occurrence of the jam, the process returns to step 5.
In this case, since the jam flag FJ has not been reset, the process returns to step 7 and the document stopper return control process is performed again.

If the open flag FO is set, that is, if at least one of the paper feed cover 11 and the main body cover 13 has been opened after the occurrence of the jam, it is determined whether or not the reset flag FR is set. It is determined (step 170). Reset flag F
If R is not set, the original is detected by the first original detector 51, and the process returns to step 5. In this case, since the jam flag FJ has not been reset, the process returns to step 7 and the document stopper return control process is performed again.

If the reset flag FR is set, it is judged whether or not a document is detected by the second document detector 53 (step 171). If the document is detected by the second document detector 53, the process returns to step 5. In this case, since the jam flag FJ has not been reset, the process returns to step 7 and the document stopper return control process is performed again.

If the document is not detected by the second document detector 53, it is judged whether or not the document is detected by the third document detector 54 (step 17).
2). If the document is detected by the third document detector 54, the process returns to step 5. In this case, the jam flag F
Since J has not been reset, the process returns to step 7 and the document stopper return control process is performed again.

If the document is not detected by the third document detector 54, it is judged whether or not the document is detected by the fourth document detector 57 (step 17).
3). If the document is detected by the fourth document detector 57, the process returns to step 5. In this case, the jam flag F
Since J has not been reset, the process returns to step 7 and the document stopper return control process is performed again.

At step 173, if the document is not detected by the fourth document detector 54, the open flag FO, the reset flag FR and the jam flag F are displayed.
J is reset (step 174) and the process returns to step 5. In this case, since the jam flag FJ has been reset, the process proceeds to step 6 and shifts to the automatic document feeding process.

That is, when the jam flag FJ is set, at least one of the paper feed unit cover 11 and the main body cover 13 is opened and the originals are detected by all the first to fourth original detectors 51, 53, 54 and 57. When it is no longer detected, the jam flag FJ is reset and the automatic document feeding process is started. Further, when the jam flag FJ is set, the document stopper 41 is returned to the document leading edge positioning position when the paper feed unit cover 11 is opened or when the document is no longer detected by the first document detector 51. ..

The jam flag FJ is set as shown in FIG. 3 in addition to the case where a document jam occurs during the automatic document feeding process.
It is also set when the paper feed unit cover 11 is closed when the power of the copying machine main body 2 is turned on and the original is detected by the first original detector 51. The reason why the paper feed unit cover 11 is closed when the power of the copying machine main body 2 is turned on and the original is detected by the first original detector 51 is as follows. That is, after the recording paper jam occurs in the copying machine body 2 during the automatic document feeding process and the power of the copying machine body 2 is turned off, the documents in the automatic document feeding are not removed, and the copying machine is not removed. This is to remove the original document in the automatic document feeder when the recording paper jam of the main body 2 is released and the power is turned on.

According to this embodiment, the position of the document stopper 41 is switched by the self-holding solenoid 44 having a permanent magnet, and when the self-holding solenoid 44 is in the self-holding state, the document stopper 41 is set to the document. It is held at the paper feed position. Then, when a document jam occurs, after the paper feed unit cover 11 is opened and the separating roller pairs 22 and 23 are separated from each other, or when the document is not detected by the first document detector 51 or the first document detector 51 is detected.
After the document is no longer detected by the document detector 51, the solenoid 44 is returned and the document stopper 41 is moved to the document leading edge positioning position. Therefore, when a document exists across the paper feed roller 21 and the pair of separating rollers 24 and 25 when a jam occurs, the document can be pulled out without the load of the document stopper 41 being applied to the jammed document. ,
The original will not be damaged when it is pulled out.

Further, in the case where the original exists across the paper feed roller 21 and the pair of separating rollers 24 and 25 when the jam occurs, even if the power of the copying machine main body 2 is turned off, the original stopper 41 is provided. Is held at the document feeding position and does not move to the document leading edge positioning position, so that the document is not loaded by the document stopper 41. Therefore, even if the power of the copying machine body 2 is turned off when a document jam occurs, the jammed document can be smoothly pulled out without damaging the document.

Further, according to this embodiment, after the document is set at the reading position and before the document exchange signal is received, the front end of the next document is located at the detection position by the third document detector 54. Then, the original is placed in a standby state with the original sandwiched by the pair of registration rollers 24 and 25. Therefore,
The time from the receipt of the original exchange signal until the next original is set at the reading position and the print signal is output (original exchange time) is stable, and the copying speed can be increased. In addition, it is possible to reduce secondary paper feed failure. Further, in the secondary paper feed process, the paper feed clutch 32 does not have to be engaged when the carry motor 34 is started, so the load on the power supply when the carry motor 34 is started can be reduced.

In the above-described embodiment, in the document stopper return control processing of FIGS. 8 and 9, the document stopper 41 is opened when the paper feed unit cover 11 is opened or when the first document detector 51 no longer detects the document. Is returned to the position for positioning the leading edge of the document, but the paper feed unit cover 11
When the document is opened, the document stopper 41 is not returned to the document leading edge positioning position, and the document stopper 41 is returned to the document leading edge positioning position only when the document is no longer detected by the first document detector 51. Good. Also, when the paper feed unit cover 11 is opened or the first
When the document is not detected by the document detector 51, the document stopper 41 is not returned to the document leading edge positioning position, and the document stopper 41 is moved to the document leading edge positioning position when the jam flag FJ is reset in step 174. You may make it return to.

Further, in the document stopper return control processing of FIGS. 8 and 9, opening at least one of the paper feed unit cover 11 and the main body cover 13 is one of the conditions for resetting the jam flag FJ. Although mentioned, the opening of the paper feed unit cover 11 or the main body cover 13 may be removed from the condition for resetting the jam flag FJ. That is, steps 161-1 in the document stopper return control process of FIGS. 8 and 9.
Step 65, Step 169, and Step 17
The process of resetting the open flag FO in 4 may be omitted.

[0065]

According to the present invention, even if the power is turned off when a document jam occurs, the document is not loaded by the document stopper and can be pulled out without damage.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of an automatic document feeder.

FIG. 2 is a block diagram showing an electrical configuration of an automatic document feeder and a copying machine main body.

FIG. 3 is a flowchart showing an overall processing procedure by a CPU.

FIG. 4 is a flowchart showing a document automatic feeding process procedure.

FIG. 5 is a flowchart showing a document automatic feeding process procedure.

FIG. 6 is a flowchart showing a primary paper feed processing procedure.

FIG. 7 is a flowchart showing a secondary paper feed processing procedure.

FIG. 8 is a flowchart showing a document stopper return control processing procedure.

FIG. 9 is a flowchart showing a document stopper return control processing procedure.

FIG. 10 is an explanatory diagram for explaining a conventional example.

FIG. 11 is an explanatory diagram for explaining a conventional example.

[Explanation of symbols]

 1 Automatic Document Feeding Device 20 Document Loading Table 21 Paper Feeding Rollers 22, 23 Separation Roller Pair 41 Document Stopper 44 Solenoid 51 First Document Detector 60 Feeding Device Side Control Unit 61 CPU 62 ROM 63 RAM 70 Copier Main Unit Control Unit

Claims (3)

[Claims] 1. A document stopper for positioning the leading edge of the document when setting the document on the document mounting table is moved between a position for positioning the leading end of the document and a position for feeding the document out of the document transport path. The original stopper is freely supported, and the position of the original stopper is switched by a self-holding solenoid having a permanent magnet. When the self-holding solenoid is in a self-holding state, the original stopper is held at the original feeding position. Automatic document feeder. 2. A document detector is provided near the document feed port, and when a document jam occurs, when the document is no longer detected by the document detector, the self-holding solenoid self-holds. 2. The automatic document feeder according to claim 1, wherein the document stopper is switched to a document leading edge positioning position by releasing the state. 3. A cover which is openable and closable for covering the paper feed roller and the separating roller pair, and one roller of the separating roller pair is attached to the cover, and when a document jam occurs, the above-mentioned cover is formed. 2. The automatic document feeder according to claim 1, wherein when the cover is opened, the self-holding state of the self-holding solenoid is released to switch the document stopper to a document leading edge positioning position.