JPH10167521A - Automatic document sheet carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic document carrying device which can sense normally the crosswise length of the fed document sheet even in case it is perforated by punching, etc., in the condition that a connector is mismounted on the sensor to sense the document width. SOLUTION: Monitoring is made to know how many of three input ports PA0-PA2 is/are put in Hi level in the period that resist sensor is on (that is, any document sheet is passing the area with sensors SN1-SN3), and thereby judgement is made from the obtained number of Hi-level input ports which SN1-SN3 is turned on to determine the length of the fed document sheet.

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 provided in an image forming apparatus such as a copying machine and a facsimile machine, and more particularly, to detecting the width of a sheet material having a punch hole or the like in the width direction. And an automatic document feeder capable of detecting the length in the width direction even when a connector is incorrectly attached to a sensor.

[0002]

2. Description of the Related Art Generally, an automatic document feeder (hereinafter, simply referred to as an ADF) used for an image forming apparatus such as a facsimile machine and a copying machine has a plurality of sensors arranged in a direction orthogonal to a document feed direction. By detecting the ON / OFF state of this sensor, the length of the document in the width direction is detected.

[0003] The sensor usually has the same polarity and connector, and may be arranged in a close place so that various sizes in Japan or abroad can be detected at the same arrangement position. In many cases, if the connector is attached to a sensor other than the sensor to which it should be attached, the length in the width direction of the document cannot be detected normally. I try to change the color and the length of the harness.

When the color of the connector is changed or the length of the harness is changed, the A
The cost of the DF increases, and a change instruction must be given each time the assembling work is performed, which causes a problem that workability is poor. Therefore, in order to prevent such a problem from occurring, for example,
There is one described in JP-A-7-146705.

This device uses a plurality of sensors having the same polarity and the same connector and a fixed ON / OFF order, and outputs the connectors in order from the connector to be coupled to the sensor having the highest ON / OFF order. Is determined, the sensor and the connector coupled to the sensor are specified, so that the length of the document in the width direction can be detected even when the connector is erroneously attached to the sensor.

[0006]

However, in such a conventional method of detecting an erroneous connection of a connector, a document having a large number of sprocket holes, such as a punch hole for a file or a computer form, is formed by an ADF. When the document is conveyed, if the sensor does not detect the document itself by directly detecting a punch hole or the like at the time of detecting the document width (eg, when setting the document) (when the sensor is turned off)
In this case, the order of ON / OFF of the sensors is different from the actual document width, and there is a problem that the document width is erroneously detected.

On the other hand, as a device for preventing a document from being erroneously detected by a punch hole or the like opened in the document, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 57-9656. This device has a pair of sensors in a direction orthogonal to the document transport direction, and when one sensor detects the document and the other sensor does not detect the document after a lapse of a predetermined time, the skew of the document is reduced. Generates a jam signal as if it had occurred,
When one sensor detects the document and the other sensor once detects the document and then goes back to the non-detection state, it detects a punch hole or the like and feeds the document without generating a jam signal. I do it.

However, if this is applied to a device for detecting the length of a document in the width direction, a sensor for detecting a punched hole and a sensor for detecting the document width are required. About twice as much,
In addition to the problem of increasing the cost of the ADF, if a punch hole or the like is opened at a position where the two sensors are simultaneously turned off, the document width cannot be detected normally as described above. A problem occurred,
Not practical.

Therefore, the present invention detects the length of a document in the width direction normally even when a perforated document such as a punch hole is transported in a state where a connector is erroneously attached to a sensor for detecting the width of the document. It is an object of the present invention to provide an automatic document feeder capable of performing the following.

[0010]

According to the first aspect of the present invention,
In order to solve the above-mentioned problem, a plurality of sensors having the same polarity and connector are arranged in a direction perpendicular to the document transport direction, and are attached to each sensor according to the length of the document in the width direction. In the automatic document feeder capable of detecting the length of the document in the width direction based on a signal output from the sensor through the connected connector, the sensor is operated for a predetermined time while the document passes through the sensor. It is characterized by having control means for detecting whether or not the above operation has been performed, and for determining the length of the document in the width direction based on the number of operated sensors.

In this case, by detecting the number of operations of the sensor while the document is passing through the sensor, even if the connector is erroneously attached to the sensor, the length of the document in the width direction can be determined from the number of operations of the sensor. Can be detected. Also, by determining whether the sensor has been operated for a predetermined time or more while the document is passing through the sensor, the sensor detects the document width at the timing of detecting the document width, such as when setting the document. Even when a formed punch hole or a sprocket hole of a computer foam or the like is detected, the original can be reliably detected, and erroneous detection of the original width can be prevented.

As a result, the length of the document in the width direction can be reliably detected without being affected by punch holes and the like.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 17 are views showing an embodiment of the automatic document feeder according to the present invention. First, the configuration will be described. 1 and 2, reference numeral 1 denotes an automatic document feeder (hereinafter, referred to as an ADF). The ADF 1 has a contact glass 2 provided above a copying machine (not shown) as an image forming apparatus and constituting a part of an exposure position. Covering.

The ADF 1 feeds a document table 3 on which a document bundle composed of a plurality of documents can be placed, and a lowermost document separated from the document bundle on the document table 3 one by one. Thereafter, separating / transporting means 4 for transporting toward the contact glass 2, transporting means 5 for transporting the document separated and transported from the separating / transporting means 4 to a document exposure position on the contact glass 2, Paper discharge means 7 having a paper discharge path for discharging the above-exposed document onto the document discharge section 6 and a turn path for reversing the document during double-sided document copying and returning it to the contact glass 2 again. ing.

When the original bundle is set on the original table 3, the separating / transporting means 4 comes into contact with the leading end of the original bundle to prevent the original bundle from entering inward.
A document set detection filler 9 that moves upward by contacting the leading end of the document bundle set on the document mounting table 3, a document set sensor 10 that detects the detection filler 9 in proximity to and separated from the detection filler 9, Detection filler 9 is a set sensor
When the sensor 10 detects separation from the sensor 10, the pressing lever 12 approaches the call roller 11 and presses the document bundle against the call roller 11 to feed the document bundle together with the call roller 11.
It has.

The document stopper 8 is fixed to a recall drive shaft 13 as shown in FIGS. 3 and 4, and a press lever 12 is fixed to the drive shaft 13 via a recall arm 14, and the press lever 12 is a recall arm. It is rotatably connected to 14. A document stopper 8 is connected to the drive shaft 13 so as to be swingable relative to the drive shaft 13. The stopper 8 is restricted from moving in the thrust direction by an E-ring (not shown). Notches 8a and 9a are formed in the original stopper 8 and the filler 9, respectively.
The notches 8a and 9a are in contact with each other, and
Restricts rotation beyond rotation.

The drive shaft 13 is connected to a call solenoid 17 as shown in FIG. 2, and the solenoid 17 is driven by a main control unit 18. The main control unit 18 includes a CPU (Central Processing Unit).
18a, RAM (Random Access Memory), ROM (Read
Only ADF) for executing the basic operation of the ADF 1.

When the lever 17a is constantly urged by the spring 17b, the ringing solenoid 17 rotates the pivot shaft 13.
Is rotated to a predetermined position. In this state, the original stopper 8 prevents the original bundle from entering and the pressing lever
12 is separated from the ring roller 11 (see FIG. 5). That is, the calling solenoid 17 is formed of a keep solenoid, and the plunger once pulled is kept as it is by the magnetic force of the keep solenoid.

The calling solenoid 17 detects that the original set sensor 10 has set the original bundle, outputs a signal from the set sensor 10 to the main controller 18 and depresses the start switch. When turned on based on a signal from the main control unit 18, the rotating shaft 13 is rotated in a direction opposite to a predetermined direction against the urging force of the spring 17b, and the document stopper 8 is separated from the leading end of the document bundle. At the same time, the holding lever 12 is brought into contact with the retrieving roller 11 via the document bundle (see FIG. 6).

A compression spring 16 is interposed between the presser lever 12 and the retrieving arm 14. The compression spring 16 allows the presser lever 12 to move the retrieving roller 11 through a document bundle.
The original bundle is pressed with a sufficient pressing force when it comes into contact with the original bundle. A separation roller 19, a separation belt 20, a pull-out driving roller 21, and a pull-out driven roller 21 a that is brought into contact with a pull-out driving roller 21 by a spring (not shown) are disposed downstream of the retrieving roller 11 in the document conveying direction. ing. The separation belt 20 is formed of an endless belt, and is driven by a separation belt driving roller 22. Then, the document bundle fed by the recall roller 11 was once stopped between the separation roller 19 and the separation belt 20, and then the lowermost document was separated by the frictional force between the separation roller 19 and the separation belt 20. After, separation roller 19
And the pull-out driving roller 21 is carried toward the contact glass 2.

When the registration sensor 100 detects the leading end of the bundle of originals conveyed toward the contact glass 2, the driving of the call roller 11 and the separation roller 19 is stopped, and the separation belt 20 and the pull-out driving roller 21 are stopped. Thus, the original is conveyed toward the contact glass 2. Recall roller 11 and separation roller 1 described above
9, the separation belt 20 and the pull-out driving roller 21 are driven via a transmission mechanism 24 by a sheet feeding motor 23 which is a stepping motor of the present invention.

That is, the driving force of the sheet feeding motor 23 is transmitted to a driven pulley 26 via a timing belt 25, and the driven pulley 26 transmits the driving force to a pulley 28 via a connecting shaft 27. It is supposed to. The pulley 28 transmits a driving force to a pulley 30 via a timing belt 29. The pulley 30 transmits a driving force to gears 32 and 33 via a rotating shaft 31. gear
The gear 32 is connected to the separation belt driving roller 22 via a gear group 34 and a rotating shaft 35, and the gear 32 is rotatable only in a counterclockwise direction by a one-way clutch. Also,
The gear 32 is connected to a gear 37 which can be rotated only in the counterclockwise direction by a one-way clutch via an idler gear 36. It is connected to the roller 21.

On the other hand, the gear 33 is rotatable only in the clockwise direction by a one-way clutch.
The gear 40 is connected to the separation roller 19 via a rotating shaft 41. The gear 33 is also meshed with a gear 39, and this gear 39 is a gear that can be rotated only in a counterclockwise direction by an one-way clutch via an idler gear 42.
43, and this gear 43
Connected to 11.

Accordingly, when the paper feed motor 23 is rotated clockwise in FIG. 2, the paging roller 11, the separation roller 19 and the pull-out drive roller 21 rotate counterclockwise with the separation belt 22 stopped. When the bundle of originals is fed and separated, and the leading edge of the separated originals is detected by the registration sensor 100, the feed motor is controlled by a command from the main control unit 18.
After the stoppage, the sheet feeding motor 23 rotates counterclockwise in FIG. 2 to stop the rotation of the calling roller 11 and the separation roller 19, and the separation belt 20 and the pull-out drive roller 21 rotate and follow. The separated original is conveyed toward the contact glass 2 while preventing the separated original from being separated.

The paper feed motor 23 is composed of a four-phase stepping motor. The paper feed motor 23 is controlled in torque and rotational speed by a motor driver (not shown), and the motor driver is controlled by the main controller 18. It has become. The motor driver varies the pulse width of the signal supplied to each coil of the paper feeding motor based on the four-phase input signal input from the main control unit 18 to vary the rotation speed of the paper feeding motor 23. ing.

The registration sensor 100 detects the front and rear ends of the document and outputs a signal to the main control unit 18. Reference numeral 102 denotes a document width detection sensor.
02 is configured to detect the length of the document in the width direction and output document size information to the main control unit 18. In particular,
As shown in FIG. 7, the sensor 102 includes three sensors 102a to 102c arranged in a direction orthogonal to the document conveying direction, and detects the size of the document according to each detection position. Has become.

The sensors 102a to 102c have the same polarity and connector (details will be described later), and are arranged on the same line in the width direction of the document as the registration sensor 100. A pulse generator (not shown) is provided on the rotation shaft of the pull-out driven roller 21a, and a pulse generated by the pulse generator is detected by the document length detection sensor 103. The detection signal from the sensor 103 is output to the main control unit 18.

Further, the main control unit 18 controls the registration sensor 10
When the detection information of the front and rear ends of the original is input by 0, the pulse signal of the motor driver that drives the paper feed motor 23 when passing the front and rear ends is counted, and the original length is determined by the original feed amount per pulse. Calculation and determination. Then, the main controller 18 finally detects the document length based on the detection information from the registration sensor 100 and the pulse signal of the paper feed motor 23. In addition, paper feed motor
Instead of counting the number of pulses of 23 and detecting the rotation amount of the pull-out driving roller 21, the rotation amount of the rotating shaft of the pull-out driving roller 21 may be detected by a pulse generator and a sensor.

On the other hand, the conveying means 5 inserts the original between the driving roller 51 and the driven roller 52, the endless conveying belt 53 wound around the rollers 51 and 52, and the conveying belt 53 and the contact glass 2. And a plurality of rows of pressing rollers 55 which are provided so as to be separated by a predetermined distance in the extending direction of the contact glass 2 and press the conveyor belt 53 against the contact glass 2. I have.

The transport means 5 transports the document to the exposure position by the transport belt 53 and transports the exposed document from the contact glass 2 to the paper discharge means 7. The drive roller 51 is connected to a transport belt motor 58 via a transmission mechanism 57, and is driven by the transport belt motor 58. The transport belt motor 58 is connected to a driven pulley 60 via a timing belt 59, and the driven pulley 60 transmits the driving force of the transport belt motor 58 to a pulley 62 via a timing belt 61. The pulley 62 is connected to the driving roller 51 via a rotating shaft 63, and transmits the driving force from the conveyor belt motor 58 by the above-described members.

The conveyor belt motor 58 is driven by the main control unit 18 in the counterclockwise direction in FIG. 2 so that the original together with the separation belt 20 and the pull-out driving roller 21 is transported toward the original exposure position of the contact glass 2. When a signal indicating that the trailing end of the document separated from the registration sensor 100 has been detected is input to the main control unit 18, the number of set pulses after the drive of the sheet feeding motor 23 is stopped by the main control unit 18 The document is stopped after being driven for a minute, and the document is stopped at the exposure position.

Here, the exposure position is, for example, a position where the rear end position of the document in the conveying direction coincides with the front end of the reference scale 56 on the left side which is the reference position of the contact glass 2. After the trailing edge of the document is detected, the distance is counted until the trailing edge of the document contacts the reference scale 56. Then, the document is exposed at this exposure position by a known exposure means including a light source, a mirror, a lens, a photosensitive drum and the like provided below the contact glass 2.

The paper discharging means 7 is provided with a reversing guide 71 which extends upwardly from the driven roller 52 on the contact glass 2.
And a reversing / discharge motor provided along this guide 71.
The ADF 1 is provided on the downstream side of the reversing drive roller 73 and the sheet discharge drive roller 75 operated by the
A guide roller 74 rotatably supported by the main body and a document provided downstream of the guide roller 74 and conveyed by the reversing drive roller 73 are directly discharged to the document discharge section 6 by the discharge drive roller 75. After switching the first switching position and the upper and lower surfaces of the original, the original is switched to the second switching position for returning the original to the contact glass 2 via the turn passage 77 while holding the original by the inversion driving roller 73 and the inversion exit driven roller 76. And a possible switching claw 78.

The reversing / discharge motor 72 is driven by the main control unit 18 and a timing belt 79
And is connected to the driven pulley 80 via The driven pulley 80 is connected to a pulley 82 via a rotating shaft 81, and the pulley 82 transmits a driving force from a motor 72 to pulleys 84 and 85 via a timing belt 83. The pulley 84 is connected to a paper discharge roller 75 via a rotation shaft 86, and the pulley 85 is connected to a reversal drive roller 73 via a rotation shaft 87. The driving force from the reversing / discharge motor 72 is transmitted via each member.

On the other hand, the switching claw 78 is connected to a reversing solenoid 89 via a driving shaft 88, and the reversing solenoid 89 is turned on / off by the main controller 18. When the reversing solenoid 89 is turned off, the switching pawl 78 is switched to the first switching position by pulling the drive shaft 88 in the direction of arrow B by the return spring 90. Is discharged to The reversing solenoid 89 is turned on in the double-sided mode based on an output signal from the main control unit 18. At this time, the drive shaft 88 is pulled in the direction of arrow A against the pulling force of the return spring 90. As a result, the switching pawl 78 is switched to the second switching position, and the original is returned to the contact glass 2.

A paper discharge sensor 104 is provided between the reversing drive roller 73 and the guide roller 74. The paper discharge sensor 104 detects a document and outputs this detection information to the main control unit 18. ing. The main control unit 18 drives the reversing solenoid 89 based on the detection information to change the document discharge position. On the other hand, as shown in FIG.
1 to 113 are attached. The connectors 111 to 113 are connected to input ports PAφ, Pφ of the CPU 18a via connectors 114 to 116 soldered to the board 18b of the main control unit 18, respectively.
A1 and PA2.

In the present embodiment, the CPU 18a operates while the registration sensor 100 is ON (that is, the sensor 102a
Sensor 102 during the passage of the document to
a to 102c detect whether or not the sensors 102a to 102c have been operated (turned ON) for a predetermined time or more.
The length in the width direction of the document is determined based on the number of 02c, and constitutes control means together with the registration sensor 100.

Next, a method of transporting a document by the ADF 1 will be described with reference to flowcharts shown in FIGS.
This flowchart shows a program stored in the ROM of the main control unit 18 and executed by the CPU 18a, and shows a process of conveying a document to the contact glass 2. First, the original bundle is placed on the original placing table 3 such that the image side of the original faces upward, and is set at a position where the leading end of the original abuts the original stopper 8 at the entrance of the paper feeding unit. The document bundle set to the position where it abuts the document stopper 8 lifts the detection filler 9 and determines whether or not the document set sensor 10 has detected that the document bundle has been set on the document table 3 ( Step S
1) When the document set sensor 10 is turned ON, it is determined whether or not a mode signal (whether the mode is the duplex mode or the simplex mode) is input (step S2).

Next, it is determined whether or not the mode signal is a one-sided mode signal (step S3). If the mode signal is determined to be a one-sided mode signal, whether the start switch is pressed in the mode set in the mode is determined. It is determined whether or not a paper feed signal has been input (step S
Four). On the other hand, when the signal is not the single-sided mode signal, it is determined that the mode is the double-sided mode, and it is determined whether or not the start switch is pressed in the state where the mode is set, that is, whether or not the sheet reversal signal is input. (Step S5).

When either the paper feed signal or the paper feed reversal signal is input in step S4 or step S5, the call solenoid 17 is turned on, and the paper feed motor 23 is driven to rotate clockwise in the normal direction. The motor 58 is driven to rotate forward in the counterclockwise direction, and the reversing / discharge motor 72 is driven to rotate forward in the counterclockwise direction. At this time, each motor 23, 58, 72
Starts a slow-up operation and counts the number of pulses of each motor (step S6).

That is, when the calling solenoid 17 is turned on, the rotating shaft 13 is rotated against the urging force of the spring 17b, the original stopper 8 moves upward from the original bundle S, and the pressing lever 12 is moved to the original bundle S. (See FIG. 6), the document bundle is fed by the call roller 11 and conveyed between the separation roller 19 and the separation belt 20. At this time, since the separation belt 20 is stopped because the gear 32 is restricted from rotating counterclockwise by the one-way clutch, the separation roller 19 is stopped.
The document located at the bottom of the document bundle is separated by friction separation by the separation belt 20, and only this document is separated by the separation roller 19, the pullout drive roller 20, and the pullout driven roller.
Conveyed by 20a. At this time, the main controller 18 inputs a four-phase signal to the motor driver with a gradually shortened pulse width, thereby gradually shortening the pulse width when the coil is excited by the motor driver to feed the paper. The motor 23 is started by slow-up.

Then, it is determined whether or not the slow-up of each of the motors 23 and 58 has been completed since the separation of the document was started (step S7).
It is determined whether or not the leading edge of the document has been detected based on the detection information from the registration sensor 100 (step S8). If the registration sensor 100 is not ON, it is determined whether or not the pulse count of the paper feed motor 23 has reached the set value A (step S9). The set value A is set on the document table 3
This is the number of pulses obtained by adding the jam detection allowance distance to the distance from the leading end of the document set above to the registration sensor 100. Therefore, if it is determined in step S9 that the registration sensor 100 has not been turned on and the number of pulses of the paper feed motor 23 has reached the pulse count A, it is determined that a jam has occurred and jam processing is performed.

In this jam processing, after the motors 23, 58 and 72 are slowed down, all the motors 23, 58 and 72 are stopped (step S73). Usually, in this state, the user
Since the operation of removing the jammed paper from the DF1 is performed, it is determined whether or not the jammed paper has been released based on the detection information from the registration sensor 100 and the width detection sensor 102. Step 10 is executed from the start.

On the other hand, when it is determined in step S8 that the registration sensor 100 has been turned on, the sheet feeding motor 23 and the conveying belt motor 58 are started at a slow speed (step S10). In order to start the paper feed motor 23 at a slowdown, the main controller 18 inputs a four-phase signal to the motor driver with a gradually increasing pulse width so that the pulse generated when the coil is excited by the motor driver is output. By gradually increasing the width, the feed motor 23 is started at a slow speed.

Next, it is determined whether or not the slowdown start of the sheet feeding motor 23 and the conveying belt motor 58 has been completed (step S11), and if so, the driving of the sheet feeding motor 23 and the conveying belt motor 58 is stopped. After that (step S12), as shown in FIG. 2, the sheet feeding motor 23 is driven to rotate in the counterclockwise direction, and the conveyor belt motor 58 is driven to rotate in the counterclockwise direction.
Are counted (step S13).

At this time, the rotation of the gear 33 by the one-way clutch is restricted by the reverse rotation drive of the paper feed motor 23, the call roller 11 and the separation roller 19 are stopped, and only the pull-out drive roller 21 rotates counterclockwise. I do. Also, the one-way clutch in the gear 32 is disengaged and the separation belt driving roller 22 is rotated, and the separation belt 19 stopped at the time of separation rotates in the clockwise direction, that is, in the direction opposite to the document conveyance. 11. By stopping the separation roller 19 and rotating the separation belt 20, the next document is prevented from entering the separation nip, and the document separated and conveyed first is pulled out by the drive roller 21, the driven roller 21a, and the conveyance motor.
The conveyance belt 53 is conveyed from the separation / conveyance means 4 to the conveyance means 5 by the counterclockwise rotation of the conveyance belt 53 by the driving of the 58.

Next, it is determined whether or not the slow-up of the motors 23 and 58 has been completed (step S14). When the slow-up has been completed, whether or not the sensor 100 has been turned off based on the detection information from the registration sensor 100 is determined. That is, it is determined whether or not the trailing edge of the separated document has been detected (step S15). If the registration sensor has not been turned off, it is determined whether or not the number of pulses of the paper feed motor 23 has reached the set value C. It is determined (step S16). The set value C is set to a length obtained by adding the jam detection allowance distance to the maximum original length in the feeding direction. If the number of pulses of the paper feed motor 23 has reached the set value C while the registration sensor is OFF in step S16, the above-described jam processing is executed. In step S15, the registration sensor
If it is determined that 100 has been turned off, feed motor 2
Turn off 3 and release belt 19 and pull-out drive roller 2
When 1 is stopped and only the conveyance belt motor 58 is driven to convey the document onto the contact glass 2 (step S17), it is determined whether or not the single-sided non-collision mode is set (step S18).

If it is determined in step S18 that the single-sided non-collision mode is set, it is determined whether or not the pulse count value of the conveyor belt motor 58 has reached the pulse set value B.
The set value B is a value obtained by subtracting the distance required for slowing down the sheet feeding motor 23 and the transport belt motor 58 from the distance from the registration sensor 100 to the document stop position (the position where the rear end of the document contacts the reference scale 56). Is set.

If it is determined in step S19 that the pulse count value of the conveying belt motor 58 has reached the set value B, the sheet feeding motor 23 and the conveying belt motor 58 are slowed down (step S20). Paper feed motor 23
Then, it is determined whether or not the slowdown of the transport belt motor 58 has been completed (step S21). When it is determined that the slowdown has been completed, the driving of the paper feed motor 23 and the transport belt motor 58 is stopped (step S22). ). Therefore, the original is exposed while the original is stopped at the original exposure position on the contact glass 2. The description of the processing after step S22 is omitted.

Next, based on FIGS.
A method of detecting the length of the document in the width direction will be described with reference to 02c. First, a conventional method of detecting the length of a document in the width direction will be described with reference to the drawings of the present embodiment. For the sake of convenience, the sensor 102a is referred to as a sensor SN1, a sensor 10
2b is described as a sensor SN2, and the sensor 102c is described as a sensor SN3.

First, as shown in FIG.
When a document P having a size detected by the sensors SN1 and SN2 out of SN3 is conveyed, the sensors SN1 and SN2
Is turned on and SN3 is turned off.
Is detected, it is determined that the document P has a length in the width direction corresponding to the sensors SN1 and SN2 (for example, a medium size).

Here, in the conventional detection method, when the connectors 111 to 113 are correctly mounted on the sensors SN1 to SN3, as shown in FIG. 8, the sensors SN1 and SN2 are turned on and the sensors SN3 and SN3 are turned on. Is turned off, and this signal is input to the 3-bit input port of the CPU 18a of the main control unit 18 via the connectors 111 to 113 and the connectors 114 to 116.

More specifically, SN1 is connected to input port PAφ (bit of port A) of CPU 18a via connectors 111 and 114.
φ), SN2 is connected to input port PA1 (bit 1 of port A) via connectors 112 and 115, and SN3 is connected to connectors 113 and 116.
Is normally connected to the input port PA2 (bit A of port A) through the CPU 18a, the CPU 18a sets PAφ to “Hi”.
If it is "level", it is determined that SN1 is ON, and if it is "low", it is determined that SN1 is OFF.

On the other hand, when the connector is erroneously mounted,
For example, if the connectors of SN1 and SN3 are switched as shown by the broken line, SN1 and SN2 are actually turned on.
In this case, PA2 of the CPU 18a goes to "Hi level" and PAφ goes to "Low" level. Therefore, the program judges that SN3 has been turned ON and erroneously detects the length of the document in the width direction. I have.

That is, conventionally, each input port PA
φ, PA1 and PA2 are sensors SN1, SN2 and SN
Since there was a one-to-one correspondence with 3, it was not possible to cope with a case where a signal input path was different due to erroneous mounting of a connector. Therefore, in the present embodiment, PAφ to P
How many of the three input ports of A2 are H
By monitoring while the registration sensor 100 is ON (i.e., while the original is passing through the sensors SN1 to SN3), the number of input ports that have become Hi level Which of SN1 to SN3 is turned ON is determined to detect the length of the document.

Hereinafter, the detection method will be described with reference to the flowcharts shown in FIGS. Note that this flowchart is stored in the ROM of the main control unit 18, and the CPU 18a
FIG. First, in FIG. 12, as described above, the registration sensor 100
Then, it is determined whether or not the leading edge of the document is detected and the registration sensor 100 is turned on (step S31). ON
, The registration sensor flag (RGEG
F) is set to 1 (step S32).

Next, ON / O of each of the sensors 102a to 102c is performed.
The FF state is detected (steps S33, S34). That is, a logical product of the input port (INDT7) of the CPU 18a and 07H is taken to detect the signal of the lower bit level.
Here, when all the sensors 102a to 102c are OFF, the process proceeds to SIZWDφ, and the edge flag non-execution processing shown in FIG. 13 is executed.

When any one of the sensors 102a to 102c is turned on, the process proceeds to SIZWD1, and the processing shown in steps S51 and S52 of FIG. 14 is executed to set the edge flag (SN1 EGF) of the sensor A to 1 Set to. Also,
If any two of the sensors 102a to 102c are turned on, the process proceeds to SIZWD2 and steps S61 to S64 in FIG.
Is executed to execute the processing shown in FIG.
N1EGF, SN2EGF) is set to 1.

When all of the sensors 102a to 102c are turned on, the process proceeds to SIZWD3, and proceeds to step S71 in FIG.
The processing shown in steps S77 to S77 is executed to set the edge flags (SN1 EGF, SN2 EGF, SN3 EGF) of the sensors A, B and C to 1. Next, if the registration sensor is not ON in step S31 of FIG. 12, it is determined whether or not RGEGF is set to 1 (step S35). It is determined that the end is detected and the registration sensor 100 is turned off, and the RGEGF is reset (step S3).
6).

Then, in steps S37 to S39, the number of edge flags (ie, the number of activated sensors) is determined, and in steps S40 to S43, original detection width data (ORGWD) corresponding to the number is determined. That is, the process of the above-described flowchart is performed by monitoring how many input ports of the three input ports PAφ to PA2 have reached the Hi level while the registration sensor 100 is ON, thereby setting the Hi level to the Hi level. The length of the original is detected by judging which SN1 to SN3 are turned ON from the number of input ports that have changed.

In the present embodiment, by performing such processing, for example, the input ports PA1 and PA2 are set to “Hi”.
When PAφ is “Low level” in “Level”,
Since the number of input ports at “Hi level” is two, the sensors 102a and 102b are ON, and the sensor 102c
Is determined to be OFF, and the length of the document width is determined. Therefore, connectors for the sensors 102a to 102c
Even when 111 to 113 are erroneously mounted, the document width and length can be reliably detected from the number of sensors that are ON.

Specifically, in FIG. 8 and FIG.
When the connectors 111 and 113 of the sensor 102c and the sensor 102c are mounted in reverse, the input port PAφ is
Although the document width and length cannot be measured accurately because F, PA1, and PA2 are turned on, in this embodiment, the sensor 10
Even when the connectors 111 and 113 of the sensor 2c and the sensor 102c are mounted in reverse, the two input ports PA1 and P2
By determining the document length from A2, the length of the document width can be detected regardless of the erroneous attachment of the connector.

On the other hand, in the present embodiment, as shown in FIG.
Since the sensors 102b and 102c detect whether the document width has been actuated for a predetermined time or more, the sensors 102b and 102c detect the document width at the timing when the document width is detected, such as when the document is set. The original can be reliably detected even when the sprocket hole or the notch hole is detected, and the erroneous detection of the original width can be prevented.

[0064]

According to the first aspect of the present invention, the number of actuations of the sensor while the document is passing through the sensor is detected, so that even if the connector is incorrectly attached to the sensor, the sensor is detected. , The width of the document in the width direction can be detected. Also, by determining whether the sensor has been operated for a predetermined time or more while the document is passing through the sensor, the sensor detects the document width at the timing of detecting the document width, such as when setting the document. Even when a formed punch hole or a sprocket hole of a computer foam or the like is detected, the original can be reliably detected, and erroneous detection of the original width can be prevented. As a result,
The length of the document in the width direction can be reliably detected without being affected by punch holes or the like.

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment of an automatic document feeder according to the present invention.

FIG. 2 is a schematic diagram of a drive mechanism of the automatic document feeder according to the embodiment.

FIG. 3 is a perspective view of a document stopper, a detection filler, a recall arm, and a recall roller that constitute a part of the separation / conveyance unit of the embodiment.

4A is a side view of a calling arm and a holding lever according to an embodiment, FIG. 4B is a configuration diagram of a document stopper and a detection filler, and FIG. It is a figure showing a state.

FIG. 5 is a detailed view of a separating / transporting unit according to one embodiment;
FIG. 6 is a diagram illustrating a state in which the leading end of the bundle of documents abuts on a document stopper.

FIG. 6 is a detailed view of a separating / transporting unit according to one embodiment;
FIG. 6 is a diagram illustrating a state in which a document stopper is separated from a leading end of a document bundle.

FIG. 7 is a diagram illustrating an arrangement state of a document width detection sensor and a registration sensor according to the embodiment;

FIG. 8 is a diagram illustrating a connection relationship between a document width detection sensor and a CPU according to one embodiment.

FIG. 9 is a flowchart illustrating a document conveying method according to an embodiment.

FIG. 10 is a flowchart subsequent to FIG. 9.

FIG. 11 is a diagram illustrating a state in which a document of a predetermined size is detected by a document width detection sensor and a registration sensor.

FIG. 12 is a flowchart illustrating a method for detecting the length of a document width according to an embodiment.

13 is a flowchart showing processing of SIZWDφ in FIG.

FIG. 14 is a flowchart illustrating processing of SIZWD1 in FIG. 12;

FIG. 15 is a flowchart showing processing of SIZWD2 in FIG. 12;

FIG. 16 is a flowchart showing processing of SIZWD3 in FIG. 12;

FIG. 17 is a timing chart of a registration sensor and a document width detection sensor output signal when a punch hole or the like is detected by the document width detection sensor.

[Explanation of symbols]

 1 ADF (automatic document feeder) 18 Main control unit (control means) 100 Registration sensor (control means) 102a-102c Document width detection sensor (sensor) 111-113 Connector

Claims (1)

[Claims] 1. A connector provided in a direction orthogonal to a document conveying direction and having a plurality of sensors having the same polarity and connector, and attached to each sensor according to the length of the document in the width direction. In the automatic document feeder capable of detecting the length of the document in the width direction based on a signal output from the sensor via the sensor, the sensor has been operated for a predetermined time or more while the document is passing through the sensor An automatic document feeder, comprising: a control unit for detecting whether or not the document has been scanned and determining the length of the document in the width direction based on the number of activated sensors.