JP2005060071A - Automatic document feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic document feeder for increasing a reading efficiency by disposing a plurality of sheets of documents in a document feeding route on the downstream side of a contact lens parallel with each other at specified intervals according to a document size. <P>SOLUTION: In this automatic document feeder 1, the plurality of sheets of documents are disposed in the document feeding route on the downstream side of the contact lens 19 parallel with each other at specified intervals according to the document size and the presence or absence of the abutting of the sheets when the documents are set to a document reading position. Accordingly, the document reading efficiency can be increased by properly disposing the plurality of sheets of the documents parallel with each other on the contact glass 19. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an automatic document feeder, and more specifically, a plurality of documents are placed on a document conveyance path after a contact glass between sheets according to the document size and the presence / absence of a butting set at a document reading position. The present invention relates to an automatic document feeder that is arranged side by side to improve reading efficiency and allows an image reading device to efficiently read a plurality of documents.

  2. Description of the Related Art Conventionally, in an image reading apparatus such as a copying machine, a facsimile machine, and a scanner apparatus, an automatic document conveying device that automatically conveys a document to a document reading position of the image reading device is mounted in order to improve document reading efficiency. It has become to.

  Conventionally, in an automatic document feeder, a plurality of documents set on a document table are separated one by one and sequentially conveyed with a predetermined gap between them, but in order to improve reading efficiency, In order to reduce the gap between the original sheets, a first-out process for feeding the leading edge of the next original to a predetermined first-out position has been conventionally performed.

  As an automatic document feeder that performs such advance processing, conventionally, a read document is moved to an intermediate position between a document reading position and a paper discharge unit, and the next document is fed and conveyed to the document reading position. However, an automatic document feeder has been proposed that discharges a document when the sheet discharge sensor is turned on (see Patent Document 1).

Japanese Patent Laid-Open No. 5-35020

  However, in the conventional automatic document feeder as described above, the sheet interval is fixed in advance and cannot be changed depending on the document size. There was a need.

  Therefore, according to the first aspect of the present invention, the plurality of documents placed on the document table are separated one by one by the paper feeding means and conveyed to the document reading position on the contact glass, and the next document is transferred to the document First advance to a predetermined advance position before the document reading position in the document transport direction, transport the document at the first advance position to the document reading position, and simultaneously read the document at the first advance position to the document reading position. Feeding start timing of the first-order document when transporting the read document at the position in the direction of the paper discharge means and placing a plurality of documents in parallel on the document transport path after the document reading position with a predetermined gap between them Is changed according to the size in the document transport direction of the last read document detected by the document length detecting means for detecting at least the length of the document in the document transport direction. Accordingly, by changing the document juxtaposition interval, the document discharge time and document replacement time depending on the document size are shortened, the document reading efficiency is improved, and the number of juxtaposed small-sized documents is prevented from becoming too large. An object of the present invention is to provide an automatic document feeder that can prevent document skew from occurring and has good usability.

  According to the second aspect of the present invention, a butting function for performing a butting operation of striking the document against the document scale at the document reading position when the document is set at the document reading position, and a butting operation using the butting function A selection function is provided for selecting whether or not to perform, and during the non-butting operation in which the abutting operation is not performed, the feeding start timing of the first document is delayed by a predetermined time compared to the case where the abutting operation is performed. This prevents the number of documents placed side by side on the contact glass from becoming too large during the non-butting operation, suppresses the document skew during the document discharge operation, and further improves the availability of automatic document conveyance. The object is to provide a device.

  According to a third aspect of the present invention, the interval between the juxtaposed documents is determined by determining the feeding start timing of the first document based on the number of steps of the motor that conveys the read document at the document reading position in the direction of the paper discharge means. An object of the present invention is to provide an automatic document feeder that is accurate and suppresses document skew during a document discharge operation and is more highly usable.

  According to a first aspect of the present invention, there is provided an automatic document feeder that separates a plurality of documents placed on a document table one by one and feeds them to a document reading position on a contact glass, and the contact A conveying unit configured to convey a document on the glass; a sheet discharging unit configured to discharge the document conveyed from the conveying unit onto a sheet discharge table; and a document length detecting unit configured to detect at least a length in the conveying direction of the document. A plurality of originals placed on the original table are separated one by one by the paper feeding means and conveyed to the original reading position on the contact glass, and the next original is read. When the document is advanced in advance to a predetermined advance position before the position in the document conveyance direction, and the document at the advance position is transported to the document reading position, the document at the same time as the document at the advance position is transported to the document reading position. Reading position In the automatic document conveying apparatus that conveys a plurality of read documents in the direction of the paper discharge means and juxtaposes a plurality of documents on a document conveyance path after the document reading position with a predetermined gap between them, the first document The above object is achieved by changing the sheet feeding start timing in accordance with the size of the last read document detected by the document length detecting means in the document transport direction.

  In this case, for example, as described in claim 2, the automatic document feeder performs a butting operation of abutting the document against the document scale at the document reading position when the document is set at the document reading position. This function has a selection function that selects whether or not to perform the abutting operation using the abutting function, and compared with the case where the abutting operation is performed when the abutting operation is not performed. Then, the start timing of feeding the first document may be delayed by a predetermined time.

  For example, as described in claim 3, the automatic document feeder is configured to perform a feeding start timing of the first document, and a motor step for conveying the read document at the document reading position toward the paper discharge unit. It may be determined based on the number.

  According to the automatic document feeder of the first aspect of the invention, the plurality of documents placed on the document table are separated one by one by the sheet feeding means and conveyed to the document reading position on the contact glass, The next document is advanced in advance to a predetermined first position before the document reading position in the document transport direction, the document at the first position is transported to the document reading position, and the document at the first position is transported to the document reading position. At the same time, when the read document is transported in the direction of the paper discharge unit at the document reading position and a plurality of documents are juxtaposed on the document transport path after the document reading position with a predetermined gap between them, the first document The document feed start timing is changed according to the size of the last read document detected by the document length detection means for detecting at least the length of the document in the document transport direction. By changing the document juxtaposition interval according to the size of the document, it is possible to shorten the document discharge time and the document replacement time according to the document size, improve the document reading efficiency, and arrange the number of small-size documents juxtaposed. Therefore, it is possible to prevent the document skew from occurring and to improve the usability.

  According to the automatic document feeder of the invention described in claim 2, the butting function for performing a butting operation of butting the document against the document scale at the document reading position when the document is set at the document reading position, and the butting function A selection function for selecting whether or not to perform the abutting operation is provided, and during the non-abutting operation in which the abutting operation is not performed, feeding of the first-out document is performed as compared with the case where the abutting operation is performed. Since the start timing is delayed by a predetermined time, it is possible to prevent an excessive number of documents juxtaposed on the contact glass during the non-contact operation, and to suppress document skew during the document discharge operation. The property can be further improved.

  According to the automatic document feeder of the invention described in claim 3, since the feeding start timing of the first document is determined based on the number of steps of the motor that conveys the read document at the document reading position in the direction of the paper discharge means. The interval between the documents placed side by side can be made accurate, the document skew during the document discharge operation can be suppressed, and the usability can be further improved.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, since the Example described below is a suitable Example of this invention, various technically preferable restrictions are attached | subjected, However, The scope of the present invention limits this invention especially in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

  1 to 30 are diagrams showing an embodiment of an automatic document feeder of the present invention. FIG. 1 is a schematic front view of an automatic document feeder 1 to which an embodiment of the automatic document feeder of the present invention is applied. It is a block diagram.

  In FIG. 1, an automatic document feeder 1 includes a paper feed mechanism 3, a paper feed roller 4, a transport unit 5, a paper discharge roller 6, a double-side claw 7, a switchback claw 8, a switchback roller 9, and a housing 2. A switchback path 10, a paper discharge path 11, a paper discharge outlet roller 12, a document set sensor 13, a pullout sensor 14, a registration sensor 15, a paper discharge inlet sensor 16, a paper discharge outlet sensor 17, and a switchback sensor 18 are accommodated. A contact glass 19 is provided at the bottom of the housing 2. In the automatic document feeder 1, a paper discharge tray (paper output table) 20 is formed at the top of the housing 2, and a document tray (document base) 21 is provided above the paper output tray 20.

  The automatic document feeder 1 is mounted on an image reading device as a main device such as an electrophotographic copying machine, and an image reading unit of the image reading device is disposed below the contact glass 19. The image reading unit of the image reading device irradiates the original conveyed to the original reading position on the contact glass 19 with reading light from a light source (not shown), and photoelectrically reflects the reflected light including the image information of the original reflected by the original. The image of the original is read by performing photoelectric conversion with the conversion element.

  As shown in FIG. 2, the automatic document feeder 1 has a circuit block configuration. The document set sensor 13 (not shown in FIG. 2), a pull-out sensor 14, a registration sensor 15, a paper discharge inlet sensor 16, In addition to a discharge exit sensor 17 and the like, a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an engine I / O 104, a main body I / F 105, a calling motor 106, A paper feed motor 107, a conveyance motor 108, a paper discharge motor 109, a switchback claw solenoid 110, a double-side claw solenoid 111, a paper discharge clutch 112, and the like are provided. Are connected by a bus 113. The operation unit 201 of the image reading apparatus main body is connected to the main body I / F 105, and the main body I / F 105 notifies the CPU 101 of the operation content of the operation unit 201 via the bus 113. The operation information of the collected automatic document feeder 1 is notified to the operation unit 201 as necessary.

  The engine I / O 104 is connected to the document set sensor 13 (not shown) and the pull-out sensor 14 to the paper discharge clutch 112. The engine I / O 104 is connected between the CPU 101 and the respective parts via the bus 113. Send and receive information.

  In the automatic document feeder 1, the CPU 101 controls each part of the automatic document feeder 1 while using the RAM 103 as a work memory based on a program in the ROM 102 to perform processing as the automatic document feeder 1 and will be described later. The conveyance control process is executed.

  In the automatic document feeder 1, a plurality of documents are placed on the document tray 21, the document set sensor 13 detects the documents placed on the document tray 21, and is sent to the CPU 101 via the engine I / O 104. Output.

  In the paper feed mechanism 3, when the calling motor 106, which is a stepping motor, rotates forward, the roller portion on the side of the document tray 21 moves up and down as shown by a double arrow in FIG. By rotating forward, as shown in FIG. 4, the paper feed mechanism 3 rotates clockwise, and the paper feed roller 4 rotates counterclockwise, so that a plurality of documents set on the document tray 21 are rotated. Are fed one sheet at a time from the upper document. Further, as shown in FIG. 5, the paper feed motor 107 is reversed, the paper feed mechanism 3 is stopped, and only the paper feed roller 4 rotates counterclockwise, thereby conveying the document. The sheet feeding mechanism 3 and the sheet feeding roller 4 function as sheet feeding means as a whole.

  The pull-out sensor 14 detects a document sent from the document tray 21 by the paper feed mechanism 3, and the paper feed roller 4 detects the document sent by the paper feed mechanism 3 between the contact glass 19 and the transport unit 5. Feed paper.

  The registration sensor 15 is disposed in front of the contact glass 19 in the document conveyance direction by the paper feed roller 4, detects the document conveyed on the contact glass 19, and outputs it to the CPU 101 via the engine I / O 104. .

  The CPU 101 can detect the length of the document from the on / off timing of these sensors 14 and 15 by using the pull-out sensor 14 and the registration sensor 15 as the document length detection means, and also uses it as a document standby position. .

  As shown in FIG. 6, when the conveyance motor (motor) 108 rotates in the forward direction, the conveyance roller 5a rotates the driving roller 5a counterclockwise, thereby causing the conveyance belt 5b to rotate counterclockwise. The original is conveyed between the conveying belt 5b and the contact glass 19 by the paper feeding roller 4 and conveyed to the original reading position on the contact glass 19 to be temporarily stopped. When the original is read by the scanning unit and the reading of the image of the original is completed, the original on which the image has been read is conveyed to the paper discharge roller 6.

  Further, as shown in FIG. 7, when the conveyance motor 108 is reversed, the conveyance unit 5 rotates its driving roller 5a in the clockwise direction, and rotates the conveyance belt 5b in the clockwise direction to complete the reading once. After the reversed double-sided document is turned upside down by the switchback path 10, it is again conveyed back to the document reading position on the contact glass 19.

  The paper discharge entrance sensor 16 is disposed in front of the paper discharge roller 6, detects the original conveyed to the paper discharge roller 6 by the transport unit 5, and outputs it to the CPU 101 via the engine I / O 104. .

  The switchback sensor 18 is provided in the switchback path 10 that is used when paper is discharged on one side of the document, and detects the presence or absence of a document in the switchback path 10.

  The paper discharge roller 6 conveys the original conveyed by the conveyance unit 5 to the double-sided claw 7, and the inclination of the double-sided claw 7 changes as the double-sided claw solenoid 111 is turned on / off as shown in FIG. Thus, switching is made between a paper discharge conveyance path for discharging the document through the paper discharge path 11 onto the paper discharge tray 20 at the paper discharge outlet roller 12 and a reverse conveyance path for conveying the original to the switchback path 10 via the switchback claw 8. To transport. The paper discharge roller 6, the double-sided claw 7, the switchback claw 8, and the paper discharge outlet roller 12 function as a paper discharge unit as a whole.

  As shown in FIG. 9, the inclination of the switchback claw 8 changes when the switchback claw solenoid 110 is turned on / off, and the document fed in the direction of the switchback claw 8 by the double-sided claw 7 is reversed again. A path of feeding in the direction of conveyance to the document reading position on the contact glass 19 by the conveyance unit 5 rotating in the opposite direction, and the document fed in the direction of the switchback claw 8 by the double-sided claw 7 are switched back by the switchback roller 9. The document is fed to the path 10 and switched from the switchback path 10 to the path for discharging the document on the switchback roller 9 through the sheet discharge path 11 onto the sheet discharge tray 20 through the sheet discharge outlet roller 12.

  The switch back roller 9 is rotationally driven by the paper discharge motor 109 and, as described above, performs normal rotation and reversal so that the document fed by the switch back claw 8 is fed into the switch back path 10. Then, the document in the switchback path 10 is sent out.

  The paper discharge outlet roller 12 is rotationally driven by a paper discharge motor 109 and discharges the original conveyed to the paper discharge path 11 onto the paper discharge tray 20.

  The paper discharge clutch 112 turns on / off driving of the paper discharge roller 6 that is driven and controlled by the paper discharge motor 109, the switch back roller 9, and the paper discharge outlet roller 12. To do. That is, when the paper discharge motor 109 rotates in the normal direction, the paper discharge roller 6, the switch back roller 9 and the paper discharge outlet roller 12 all rotate counterclockwise as shown in FIG. As shown in FIG. 11, the paper discharge roller 6 and the paper discharge outlet roller 12 rotate counterclockwise, and the switchback roller 9 rotates clockwise. If the paper discharge clutch 112 is off when the paper discharge motor 109 rotates forward or reverse, the paper discharge roller 6 becomes free as shown in FIG. Only the roller 12 rotates according to the normal rotation or reverse rotation of the paper discharge motor 109.

  The main body operation unit 201 includes various operation keys such as a numeric keypad, a start key, a mode key, and a one-touch key, and includes various LEDs and an LCD (Liquid Crystal Display). Then, setting of various operation modes and various operation instruction operations of the image reading apparatus which is the main body apparatus are performed, and the contents inputted with the operation keys and various information notified from the main body apparatus to the operator are displayed on the LCD.

  Next, the operation of this embodiment will be described. The automatic document feeder 1 according to this embodiment sets a space between a plurality of sheets placed side by side on the contact glass 19 based on the document size and the document abutting setting state for determining whether or not to abut the document. Increase efficiency.

  That is, as described above, the automatic document feeder 1 is assembled in an image reading apparatus as a main body device such as a copying apparatus, and the image reading apparatus uses the automatic document feeder 1 to perform a copy operation of a plurality of documents. For this purpose, the user sets a plurality of documents on the document tray 21 of the automatic document feeder 1, and the single-side mode for reading only one side of the document, the double-sided reading mode for reading both sides of the document, and documents of different sizes. A necessary mode setting operation such as a mixed document mixed mode is performed by the main body operation unit 201 of the image reading apparatus, and then the start key 203 of the main body operation unit 201 is pressed.

  In the following description, it is assumed in the flowcharts of FIGS. 13 to 16 and the operation explanatory diagrams of FIGS. 17 to 30 that single-sided scanning of three A4-size originals, hereinafter, originals Org1, Org2, and org3 is performed. This will be explained based on.

  In the automatic document feeder 1, when a plurality of A4-size single-sided originals are set on the original tray 21, the original setting sensor 13 detects the setting of the originals, and various necessary setting operations are performed by the image reading apparatus. When the start key is pressed in the main body operation unit 201, first, as shown in FIG. 13, a group process GS1 for starting feeding of the first document Org1 based on a paper feed / discharge command is performed.

  That is, in the group process GS1, the CPU 101 receives a paper feed / discharge command from the image reading apparatus (step S101), and starts feeding the first original document Org1 by the paper feed mechanism 3 and the paper feed roller 4 (step S101). S102). When the first document Org1 is fed, the number of steps of the feed motor 107 from when the document reaches the registration sensor 15 and the registration sensor 15 is turned on until the trailing edge of the document passes through the pull-out center 14 Calculate from and decide.

  Next, the CPU 101 determines whether or not to perform a document abutting operation for abutting the document against the document scale when the document is fed to the document reading position. Then, the group processing GS2 is performed to transmit the document stop signal and advance the second document Org2.

  In other words, in the group process GS2, the CPU 101 checks whether or not the setting for abutting the document is made (step S103). If the setting for the butting of the document is set, as shown in FIG. When the butting setting of the first document Org1 at the document reading position is completed (step S104), a signal indicating the document stop is transmitted to the image reading device, and the first document Org1 at the document reading position is transmitted by the image reading device. At the same time, the calling motor 106 and the paper feed motor 107 are driven to start the first-out of the second original document Org2 (step S105).

  Next, the CPU 101 performs a group process GS3 for starting first discharge of the second original document Org2 and starting discharge of the first original document Org1 based on a paper supply / discharge command from the image reading apparatus.

  That is, in the group process GS3, when the CPU 101 completes reading of the first document Org1 and receives a paper supply / discharge command from the image reading apparatus (step S106), the CPU 101 sends the second document Org2 to a predetermined document first. Waiting for completion of first-out feeding and stopping to the position (step S107), the delivery operation of the first original document Org1 is started by the transport section 5 and the discharge roller 6 and the second original document Org2 is started. The paper feeding operation to the original reading position on the contact glass 19 is started (step S108).

  Next, the CPU 101 performs a group process GS4 that performs from the abutment of the second original G2 to the start of the first advance of the third original Org3.

  That is, in the group process GS4, the CPU 101 performs abutting setting of the second document Org2 to the document reading position on the contact glass 19, and as shown in FIG. 18, the document of the second document Org2 When the abutting setting at the reading position is completed (step S109), a signal indicating the document stop is transmitted to the image reading device, and reading of the second document Org2 at the document reading position is started by the image reading device. At the same time, the calling motor 106 and the paper feed motor 107 are driven to start the first-out of the third original document Org3 (step S110). When the image reading device receives the document stop signal, the image reading device starts reading the second document Org2 at the document reading position on the contact glass 19, and when the reading is completed, a paper feed / discharge command is sent to the automatic document transport device 1. Send.

  Next, as shown in FIG. 14, the CPU 101 checks the completion of the reading of the second original document Org2 and the completion of the first advance of the third original document G3, and feeds the third original document Org3 and the second original document. A group process GS5 for starting paper discharge of Org2 is performed.

  That is, when the CPU 101 completes the reading of the second original document Org2 and receives a paper supply / discharge command from the image reading apparatus as shown in FIG. 14 (step S111), the first original completion of the third original document Org3 is completed. (Step S112), the paper feed motor 107 is rotated to start feeding the third original document Org3, and discharge the first original document Org1 and the second original document Org2. (Step S113).

  Next, the CPU 101 performs a group process GS6 for processing from the setting of the third document Org3 to the reading position to the discharge of all the documents.

  That is, when the CPU 101 completes the abutting setting of the third original document Org3 to the original reading position on the contact glass 19 (step S114), the CPU 101 transmits a signal indicating the original stop to the image reading apparatus. As shown, the discharge of the first document Org1 and the second document Org2 is stopped, and the three documents Org1 to Org3 are juxtaposed on the contact glass 19, that is, on the document transport path (step S115). ). When the image reading device receives the document stop signal, the image reading device starts reading the third document Org3 at the document reading position on the contact glass 19. When the reading is completed, the image reading and discharging command is sent to the automatic document conveying device 1. Send.

  Then, the CPU 101 waits for reception of a paper discharge command from the image reading apparatus (step S116), and as shown in FIGS. 20 to 23, all of the first original document Org1 to the third original document Org3 are displayed. The originals Org1 to Org3 are sequentially discharged, and the process ends (step S117). At this time, the automatic document feeder 1 first sends the first document Org1 into the switchback path 10 as shown in FIG. 20, and then discharges it from the switchback path 10 as shown in FIG. Inverted and discharged on the paper tray 20, and thereafter, similarly, the second original document Org2 is discharged onto the discharge tray 20 as shown in FIG. 22, and then the third original document Org3. Are discharged onto a paper discharge tray 20 as shown in FIG.

  When the document abutting setting is not set in step S103 in FIG. 13, as shown in FIG. 15, the first document Org1 is set to the document reading position by the non-document abutting and the third document is set. A group process GS7 and a group process GS8 for processing a series of operations up to the start of the advance out of Org3 are performed.

  That is, when the document abutting setting is not set in step S103, the CPU 101 performs the non-abutting setting of the first document Org1 at the document reading position on the contact glass 19, and the non-abutting setting is completed. Then (step S118), a signal indicating that the document is stopped is transmitted to the image reading apparatus. When the image reading apparatus starts reading the first document Org1 at the document reading position, at the same time, as shown in FIG. Then, the calling motor 106 and the paper feed motor 107 are driven to start the first-out of the second original document Org2 (step S119).

  Next, when the CPU 101 completes reading of the first document Org1 and receives a paper feed / discharge command from the image reading apparatus (step S120), the CPU 101 transports the second document Org2 to a predetermined document first-out position. In step S121, the first document Org1 is discharged by the transport unit 5 and the discharge roller 6 (step S122), and the first document Org1 is started. It is checked whether or not the number of steps of the transport motor 108 for discharging the paper sheet is equal to or greater than a preset specified value N (step S123).

  As shown in FIG. 24, the CPU 101 starts the feeding operation of the second original document Org2 when the number of motor steps of the transport motor 108 is rotated by a predetermined value N or more (step S124). When the non-abutting set of Org2 is performed and the non-abutting set is completed (step S118), as shown in FIG. 26, a signal indicating a document stop is transmitted to the image reading apparatus, and the image reading position is read by the image reading apparatus. The discharge operation of the first document Org1 is stopped, and the first-out of the third document Org3 is started (step S126).

  Next, as shown in FIG. 16, the CPU 101 performs a group process GS9 from the reception of the discharge command to the start of the discharge operation of the second original document Org2.

  That is, the CPU 101 completes the non-abutting setting of the second document Org2 in step S126 of FIG. 15, transmits a document stop to the image reading apparatus, and stops the discharge operation of the first document Org1. When the first delivery of the third document Org3 is started, as shown in FIG. 16, it waits for the receipt of a paper feed / discharge command from the image reading apparatus (step S127), and the third document Org3 After confirming the completion of the first-out (step S128), the transport motor 108 is driven to start discharging the first document Org1 and the second document Org2 (step S129).

  Next, the CPU 101 checks whether or not the number of steps of the transport motor 108 for discharging the first and second originals Org1 and Org2 is equal to or greater than a predetermined value N set in advance (step S130).

  As shown in FIG. 26, the CPU 101 starts the feeding operation of the third document Org3 when the number of motor steps of the transport motor 108 is rotated by a predetermined value N or more (step S131), and the third document. When the non-abutting set of Org3 is performed and the non-abutting set is completed (step S132), as shown in FIG. 27, a signal indicating a document stop is transmitted to the image reading apparatus, and the image reading position is read by the image reading apparatus. The discharge operation of the second original document Org2 is started (step S133). When the image reading device receives the document stop signal, the image reading device starts reading the third document Org3 at the document reading position on the contact glass 19. When the reading is completed, the image reading and discharging command is sent to the automatic document conveying device 1. Send.

  Next, the CPU 101 performs group processing GS10 for processing from reception of the paper discharge command to discharge of all originals.

  That is, in the group process GS10, the CPU 101 waits for reception of a discharge command from the image reading apparatus (step S134), and the discharge of the first original document Org1 is completed as shown in FIGS. If it is confirmed (step S135), the second original document Org2 and the third original document Org3 are sequentially discharged, and all the original documents Org1 to Org3 are discharged in sequence, and the process ends (step S136). . At this time, the automatic document feeder 1 first feeds the first document Org1 into the switchback path 10 and then reverses it from the switchback path 10 onto the paper discharge tray 20 as shown in FIG. Thereafter, in the same manner, the second original document Org2 is discharged onto the discharge tray 20 as shown in FIG. 29, and the third original document Org3 is shown in FIG. Then, the paper is discharged onto the paper discharge tray 20.

  As described above, the automatic document feeder 1 according to the present embodiment separates a plurality of documents placed on the document tray 20 one by one by the sheet feeding mechanism 3 and the sheet feeding roller 4, and documents on the contact glass. The document is transported to the reading position, the next document is first advanced to a predetermined first position before the document reading position, and the document at the first position is transported to the document reading position. At the same time as transporting the original to the original reading position, the read original at the original reading position is transported in the direction of the paper discharge roller 6 to place a plurality of originals on the original transport path after the original reading position with a predetermined space between them. The juxtaposition start timing of the first document is changed in accordance with the size of the last document read by the pull-out sensor 14 and the report sensor 15 in the document transport direction.

  Accordingly, by changing the juxtaposition interval of the originals according to the size of the originals in the original conveyance direction, the original discharge time and the original replacement time according to the original size can be shortened, and the reading efficiency of the originals can be improved. It is possible to prevent an excessive increase in the number of juxtaposed small-size documents, prevent document skew from occurring, and improve usability.

  In addition, the automatic document feeder 1 of the present embodiment uses an abutting function for performing an abutting operation for abutting the document against the document scale at the document reading position when the document is set at the document reading position, and the abutting function. In the non-butting operation in which the abutting operation is not performed, a selection function for selecting whether or not to perform the abutting operation is provided. Is delayed for a predetermined time.

  Accordingly, it is possible to prevent an excessive number of documents juxtaposed on the contact glass 19 during the non-butting operation, and to suppress document skew during the document discharge operation, thereby further improving the usability. be able to.

  Further, the automatic document feeder 1 according to the present embodiment determines the start timing of feeding the first document based on the number of steps of the motor that conveys the read document at the document reading position in the direction of the discharge roller 6.

  Accordingly, it is possible to accurately set the interval between the documents placed side by side to suppress the document skew during the document discharge operation, and to further improve the usability.

  The invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to the above, and various modifications can be made without departing from the scope of the invention. Needless to say.

  Mounted on image reading devices such as scanners, facsimile machines, and copying machines, and multiple documents on the document transport path after the contact glass between the papers depending on the size of the document and whether or not the butting set is performed at the document reading position Can be applied to an automatic document feeder that allows a plurality of documents to be read efficiently by the image reading device.

1 is a schematic front view of an automatic document feeder to which one embodiment of an automatic document feeder of the present invention is applied. FIG. 2 is a circuit block diagram of a main part of the automatic document feeder in FIG. 1. FIG. 4 is a diagram illustrating a sheet feeding operation of the sheet feeding mechanism in FIG. 1. FIG. 2 is an operation explanatory diagram of the sheet feeding mechanism and the sheet feeding roller in a state where the sheet feeding mechanism in FIG. 1 rotates clockwise and the sheet feeding roller rotates counterclockwise. FIG. 3 is an operation explanatory diagram of the sheet feeding mechanism and the sheet feeding roller in a state where the sheet feeding mechanism in FIG. 1 is stopped and only the sheet feeding roller is rotated counterclockwise. FIG. 3 is an operation explanatory diagram of the conveyance unit in a state where the conveyance unit of FIG. FIG. 2 is an operation explanatory diagram of the conveyance unit in a state where the conveyance unit of FIG. Operation | movement explanatory drawing of the double-sided nail | claw of FIG. Operation | movement explanatory drawing of the switchback nail | claw of FIG. FIG. 3 is an operation explanatory diagram of the paper discharge roller, the switch back roller, and the paper discharge outlet roller in FIG. 1. FIG. 3 is an operation explanatory diagram of the paper discharge roller, the switch back roller, and the paper discharge outlet roller of FIG. FIG. 3 is an operation explanatory diagram of the paper discharge roller, the switch back roller, and the paper discharge outlet roller in FIG. 1. 3 is a flowchart showing a paper feed control process by the automatic document feeder of FIG. 14 is a flowchart showing processing subsequent to the paper feed control processing of FIG. 14 is a flowchart showing processing subsequent to the paper feed control processing of FIG. 16 is a flowchart showing processing subsequent to the paper feed control processing of FIG. FIG. 3 is an operation explanatory diagram of a state in which the first document of the automatic document feeder of FIG. 1 is abutted and set at a document reading position on a contact glass and a second document is conveyed to a first-out position. The first document of the automatic document feeder shown in FIG. 17 is fed first, the second document of the first delivery is set against the document reading position on the contact glass, and the third document is conveyed to the first delivery position. FIG. The first document of the automatic document feeder shown in FIG. 18 is transported to the discharge roller, the second document is forwarded, and the first third document is set against the document reading position on the contact glass. FIG. FIG. 20 is an operation explanatory diagram of a state in which the first document of the automatic document feeder of FIG. 19 is conveyed to the switchback path and the second and third documents are conveyed in the paper discharge direction, respectively. FIG. 21 is an operation explanatory diagram of a state in which the first document of the automatic document feeder of FIG. FIG. 21 is an operation explanatory diagram of a state in which the second document of the automatic document feeder of FIG. 20 is switched back by a switchback path, discharged to a sheet discharge tray, and conveyed in the discharge direction. FIG. 24 is an operation explanatory diagram of a state in which the third document of the automatic document feeder of FIG. FIG. 3 is an operation explanatory diagram of a state in which the first document of the automatic document feeder of FIG. 1 is set in a document reading position on a contact glass without being abutted and a second document is conveyed to a first-out position. FIG. 25 is an operation explanatory diagram of a state in which the first document of the automatic document feeder of FIG. 24 is advanced by N steps of a transport motor. The first sheet of the automatic document feeder shown in FIG. 25 is further advanced, the second-first document is set against the document reading position on the contact glass in a non-abutting manner, and the third document is conveyed to the first-position. FIG. FIG. 27 is an operation explanatory diagram of a state in which the first and second originals of the automatic original conveying apparatus in FIG. 26 are advanced by N steps of the conveying motor. FIG. 28 is an operation explanatory diagram of a state in which the first document is transported to the switchback path after the third document of the automatic document feeder of FIG. FIG. 29 is an operation explanatory diagram of a state in which the second document of the automatic document feeder of FIG. 28 is switched back by a switchback path, discharged to a sheet discharge tray, and transported a third document in the sheet discharge direction. FIG. 30 is an operation explanatory diagram of a state in which a third document of the automatic document feeder of FIG. 29 is switched back through a switchback path and then discharged onto a sheet discharge tray.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automatic document feeder 2 Case 3 Paper feed mechanism 4 Paper feed roller 5 Transport part 6 Paper discharge roller 7 Double-sided claw 8 Switchback claw 9 Switch back roller 10 Switchback path 11 Paper discharge path 12 Paper discharge exit roller 13 Document set Sensor 14 Pull-out sensor 15 Registration sensor 16 Paper discharge inlet sensor 17 Paper discharge outlet sensor 18 Switchback sensor 19 Contact glass 20 Paper discharge tray 21 Document tray 101 CPU
102 ROM
103 RAM
104 Engine I / O
105 Main unit I / F
106 Calling Motor 107 Paper Feed Motor 108 Carrying Motor 109 Paper Discharge Motor 110 Switchback Claw Solenoid 111 Double-side Claw Solenoid 112 Paper Discharge Clutch 113 Bus 201 Main Body Operation Unit

Claims (3)

  A sheet feeding unit that separates a plurality of documents placed on the document table one by one and feeds them to a document reading position on the contact glass, a conveyance unit that conveys the document on the contact glass, and the conveyance A document discharge unit that discharges the document conveyed from the unit onto a sheet discharge table; and a document length detection unit that detects at least a length of the document in the conveyance direction, and is placed on the document table. A plurality of originals are separated one by one by the paper feeding means and conveyed to the original reading position on the contact glass, and the next original is moved to a predetermined first position before the original reading position in the original conveying direction. When the document in the first-out position is transported to the document reading position in advance, the document at the first document reading position is moved in the direction of the paper discharge unit simultaneously with the transport of the document at the first-out position to the document reading position. Transport In an automatic document feeder that places a plurality of documents side by side on a document conveyance path after the document reading position with a predetermined space between them, the feeding start timing of the first document is determined by the document length detection means. An automatic document feeder, wherein the detected document is changed according to the size of the last document read in the document conveyance direction.   The automatic document feeder includes an abutting function for performing an abutting operation for abutting the document against the document scale at the document reading position when the document is set at the document reading position, and an abutting operation using the abutting function. A non-butting operation in which the abutting operation is not performed, and the feeding start timing of the advance document is set to a predetermined value compared with the case of performing the abutting operation. The automatic document feeder according to claim 1, wherein the automatic document feeder is delayed. The automatic document feeder is configured to determine a feeding start timing of the first document based on a number of steps of a motor that conveys a read document at the document reading position toward the paper discharge unit. The automatic document feeder according to claim 1 or 2.

Images