JPH04240664A - Electrophotographic device provided with document feeder - Google Patents

Abstract

PURPOSE:To offer an electrophotographic copying device which stably ejects a sheet-through document though it also has the existing constitution of the device by feeding the sheet-through document by a document feeder. CONSTITUTION:A sheet-through document carrying means 40 is provided in the feeding part 15 of the document feeder, and the sheet-through document is carried to the feeding belt 22 of the feeding part 15 by the means 40. The sheet-through document carried to the belt 22 is exposed by an exposing means 16 which is stopped at a specified position while it is fed in a reverse direction to the feeding direction of a cut sheet document 13 by the belt 22. The sheet- through document is ejected through a gap formed between the feeding part 15 and a paper carrying part 10. Then, a sheet-through document ejection roller 116 for ejecting the sheet-through document is driven to be rotated in an ejecting direction only at the time of ejecting the sheet-through document.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus such as a copying machine, a printer, or a facsimile machine, and more particularly to an electrophotographic apparatus equipped with a document conveying device, so-called ADF.

0002

2. Description of the Related Art Conventionally, an electrophotographic apparatus includes a fixed document feeding means for feeding a cut sheet document;
A document feeder is often used, which includes a document feeder that can be opened and closed between a position that covers and a position that opens the document placement table of an electrophotographic device that is provided adjacent to the document feeder. There is. In such an electrophotographic device,
A plurality of cut sheet originals loaded on the original feeding means are transported one by one to a predetermined position on the original placing table by the original transporting means and then stopped, and the exposure means is moved with respect to the stopped cut sheet originals. Expose the original while doing so. After the exposure is completed, the cut sheet original is ejected to the outside of the original table.

Generally, in this type of electrophotographic apparatus, the maximum size of the document that can be handled is determined because the document is exposed while it is stopped on the document table. Usually, A3 size or DLT (double letter) size is the maximum. Such devices cannot handle documents larger than the maximum size. Therefore, for example, in Japanese Patent Application Laid-Open No. 1-172983, the document conveying means is mounted on the document table in an open state,
An electrophotographic apparatus has been disclosed that includes a document transport unit that once sends a document placed on a document feeder toward a document tray, then reverses the document, and conveys the document again to the document feeder while rubbing the document tray. There is. In this electrophotographic apparatus, the exposure means is stopped at a predetermined original exposure position, and the original is exposed while being reversely transported in the direction of the original feeding means by the original transport unit. This type of document exposure is called a sheet-through method because the document is moved while the position of the exposure means is fixed.

According to such an electrophotographic apparatus, by combining with a known reduction function, the maximum size of a document that can be handled can be increased in the document feeding direction.

[0005]

[Problems to be Solved by the Invention] However, in such a conventional electrophotographic apparatus, when exposure is performed by sheet-through, the sheet-through document conveying unit is a separate unit installed afterwards, and the document is transferred each time. Since it is necessary to attach the transport unit to the electrophotographic apparatus, there are problems in that operability is poor and the cost of the apparatus is high.

[0006] Accordingly, the invention as set forth in claim 1 provides the following advantages:
It is an object of the present invention to provide an electrophotographic apparatus that enables document exposure by sheet-through while taking advantage of the operability and conveyance reliability of a document conveyance device. In addition, the invention according to claim 2 uses a gap formed between the document conveying means and the document feeding means as a discharge path for the sheet-through document, and a discharge roller for the sheet-through document when the sheet-through document is discharged. It is an object of the present invention to provide an electrophotographic apparatus that is capable of stably ejecting a sheet-through document while following the existing apparatus configuration by rotating the original in the ejection direction.

[0007] Furthermore, the invention as set forth in claim 3 uses the ejection passage for sheet-through originals as a carry-in passage for continuous computer paper originals, and conveys the continuous computer paper originals one page at a time by the conveyance means and exposes them to light. ,
It is an object of the present invention to provide an electrophotographic apparatus that can simplify the passage of a document while supporting various types of document conveyance.

[0008]

[Means for solving the problem] The invention according to claim 1 includes:
In order to achieve the above object, there is provided a document feeding means that is fixedly arranged on an electrophotographic device and feeds out a set cut sheet document, and a document placing table of the electrophotographic device that is provided adjacent to the document feeding device. a document conveyance device having a document conveying means that can be freely opened and closed toward and away from the document table and conveys the cut sheet document to the document placing table; In an electrophotographic apparatus having an exposure means that exposes the stopped cut-sheet original while moving the original after being conveyed to a position and stopped, a sheet-through apparatus is used to feed a sheet-through original to the original conveying means. While moving the sheet-through document in a direction opposite to the conveying direction of the cut sheet document by the document feeding means and the document conveying means,
The present invention is characterized by comprising a sheet-through document exposure control means for exposing an exposure means stopped at a predetermined position.

[0009] Furthermore, in order to achieve the above object, the invention as set forth in claim 2 makes the gap formed between the original conveying means and the original feeding means an ejection passage for the sheet-through original; At least one discharge roller that can rotate in both forward and reverse directions is provided between the final end and the final position where the conveying force of the document conveying means acts, and this discharge roller rotates in the discharge direction only when a sheet-through document is discharged. The present invention is characterized by being equipped with a discharge drive means for driving.

[0010] Furthermore, in order to achieve the above object, the invention as set forth in claim 3 carries a continuous computer paper document into the document conveyance means using a sheet-through document discharge path as a carry-in passage, and the continuous computer paper document is carried in through this carry-in passage. Exposure control of a continuous computer paper document in which the continuous computer paper document is conveyed one page at a time by the document conveying means and stopped, and then the stopped continuous computer paper document is exposed to light while moving the exposure means. It is characterized by having means.

[0011]

[Operation] In the invention as set forth in claim 1 having the above configuration, while the sheet-through original fed to the original transport means is moved by the original transport means in a direction opposite to the transport direction of the cut sheet original, The original is exposed to light by the exposure means stopped at a predetermined position.

Further, in the invention according to claim 2 having the above configuration, the gap formed between the document conveying means and the document feeding means is used as a discharge path for sheet-through documents, and the gap is used for discharging sheet-through documents. The ejection roller is rotated in the ejection direction only when ejecting a sheet-through document. Further, in the invention as set forth in claim 3 having the above configuration, the ejection passage for the sheet-through original is also used as the carry-in passage for the continuous computer paper original, and the continuous computer paper original is conveyed one page at a time by the conveying means and exposed. .

[0013]

EXAMPLES The present invention will be explained below based on examples. 1 to 13 are diagrams showing an embodiment of an electrophotographic apparatus according to any one of claims 1 to 4. FIG. 1 is a side sectional view showing a copying machine as an electrophotographic apparatus. In the figure, a paper feeding section 10 serving as a document feeding means is connected to a main body 1 of a copying machine.
A cut sheet original 13 fixedly placed on the original table 12 and set on the original table 12 is sent out. Adjacent to the paper feed section 10, the copying machine main body 11 is provided with a contact glass 14 as a document mounting table. The cut sheet original 13 is transported to the contact glass 14 by a transport section 15 serving as an original transport means that can be opened and closed toward and away from the contact glass 14 . Further, on the opposite side of the conveying section 15 with the contact glass 14 in between, an exposure means 16 made of, for example, a halogen lamp is provided, and the conveying section 15 conveys the cut sheet original 13 to a predetermined position on the contact glass 14 and stops After this, the cut sheet original 13 that has been stopped is exposed while moving.

In normal use, one or more cut sheet originals 13 are set on the original table 12 with the original surface facing downward. After the original setting sensor 17 confirms that the original has been set, by pressing a copy start key (not shown) located on the copying machine, the cut sheet original 13 is transferred to the separation roller 19 by the calling roller 18.
and separation blade 20, and are separated one by one. The separated cut sheet original 13 is sent out by the pull-out roller 21 and sent to the conveying section 15. The fed-out cut sheet original 13 is sent to a predetermined position on the contact glass 14 by the conveyor belt 22 and stopped. After stopping, exposure is performed by the exposure means 16 on the main body side, after which it is conveyed again by the conveyor belt 22 and sent out from the contact glass 14. At this time, if the cut sheet original 13 is a single-sided original, the reversal switching claw 23 is at the position indicated by the solid line in the figure, and the cut sheet original 13 is sent straight to the original tray 25 by the discharge roller 24. When the cut sheet original 13 is double-sided, the reversal switching claw 2
3 and the reversing ejection claw 26 are at the position indicated by the dashed line, and are reversed by the reversing driving roller 27, guided by the reversing ejection switching claw 28 located at the solid line position, and then returned to the predetermined position of the contact glass 14 by the conveyor belt 22 that is conveyed in the reverse direction. sent to. After the back side is exposed, it is turned over again and discharged. During reversal ejection, the reversal switching claw 23, the reversal ejection claw 26, and the reversal ejection switching claw 28 are at the positions indicated by the dashed-dotted lines, and the leading edge of the document is guided to the reverse ejection guide plate 29. Then, when the trailing edge of the document passes the reversal discharge sensor 30, the reversal drive roller 27 rotates in the reverse direction, and the document is sent to the discharge roller 24 by switchback and is reversely discharged. In addition, in FIG. 1, 35 is a discharge sensor, 36 is a driven roller, and 37 is a presser Mylar.

FIGS. 2 and 3 are detailed views of the reversing section of this embodiment. FIG. 2 shows the state in which the one-sided document in the above description is ejected, and the reversal switching claw 23 and the reversal ejection claw 26 are in the solid line position in FIG. Also, Figure 3
1 shows the state when a double-sided document is reversed and reversely discharged, and the reverse switching claw 23 and the reverse discharge claw 26 are in the position indicated by the dashed-dotted line in FIG. In addition, the reverse ejection switching claw 2
8, as in FIG. 1, the solid line state indicates the time of reversal, and the dashed-dotted line state indicates the time of reversal discharge.

As described above, by providing the reverse discharge switching claw 28 and the reverse discharge guide plate 29, it is possible to set the reverse path shorter than in the conventional machine, thereby shortening the reverse time. That is, as is clear from FIG. 4 showing the reversing section of the conventional machine, the conventional machine has a reversing guide 31 made of Mylar or the like, corresponding to the reversing ejection claw 26 in this embodiment. The reversing guide 31 is fixed and is laid out so that the trailing edge of the document, after passing through the reversing guide 31, is directed toward the discharge path by the waist of the document. In addition, the reversing conveyance path secures the maximum document length around the turn roller 32, and always ensures that the leading edge of the document is on the conveyor belt 2 when being reversed and ejected.
2, and the reversing conveyance path becomes long. Note that if there is sufficient space for the reversing section, the conventional configuration may be employed in the embodiment. In addition, in FIG. 4, 33 shows a reversing drive roller, 34 shows an intermediate conveyance roller, and the same code|symbol is attached|subjected about the same structure as the above-mentioned example shown in FIGS. 1-3.

[0017] Here, the configuration according to the invention recited in claim 1 will be explained. In this embodiment, the transport unit 15 is used to transport a sheet-through original, for example, an A3 or larger original. That is, the conveying section 15 of this embodiment is provided with a sheet-through document feeding means 40, and the sheet-through document feeding means 40 feeds the sheet-through document to the conveying belt 22 of the conveying section 15. In the case of sheet-through use, one sheet-through document is turned upward and fed into the feed roller 42 along the document feed table 41. The feed sensor 43 detects the sheet-through original, and the feed roller 42 is driven and hits the entrance gate 44, completing the setting. After setting, by pressing a copy start key (not shown), the entrance gate 44 is released to the state shown by the dotted chain line, and is sent to the reversing driven roller 45 by the feed roller 42, and is guided by the reversing discharge switching claw 28 shown as the solid line. , the cut sheet original 13 is transported in a direction opposite to the transport direction of the cut sheet original 13 by a transport belt 22 that reversely transports the cut sheet original 13 over the contact glass 14 . At this time, the exposure means 16 on the copying machine main body 11 side is fixed at the center position of the conveyor belt 22 by the sheet-through original exposure control means 47 so that the influence of the reversing driven roller 45 or the sheet-through discharge roller 46 is minimized. be done. On the other hand, the sheet-through document is conveyed on the contact glass 14 by the conveyor belt 22 toward the paper feed section 10, and at this time is read by a main body scanner (not shown). A conveyor belt pressure roller 48 is provided at a position facing the scanner reading position, and this conveyor belt pressure roller 48 increases the contact pressure between the conveyor belt 22 and the contact glass 14, further stabilizing the document conveyance state. . Since the original is conveyed in both directions, the reference side scale 49 is movable as shown in FIG. 5, and when the sheet-through original is conveyed, it retreats to the dashed-dotted line state, making it possible to reverse feed the sheet-through original. The sheet-through document that has passed through the reference side scale 49 is guided by a switching plate 50 indicated by a chain line, is sent to a sheet-through discharge roller 46, and is discharged to the upper part of the paper feed section 10.

As described above, in this embodiment, the sheet-through document fed to the conveyor belt 22 is moved by the conveyor belt 22 in the opposite direction to the conveyance direction of the cut sheet document, and is moved to a predetermined position. The original can be exposed by the exposure means 16 that has been stopped. For this reason,
A sheet-through document can be conveyed by the document conveyance device, and it is possible to expose the document by sheet-through while taking advantage of the operability and conveyance reliability of the document conveyance device. Furthermore, there is no need to newly install a conveyance unit for sheet-through originals, which is advantageous in terms of operability and cost.

Here, the sheet-through discharge roller 46 according to the second aspect of the present invention is supplied with driving force through an electromagnetic clutch as a discharge drive means so that the sheet-through discharge roller 46 is driven only in the sheet-through discharge direction. . Therefore, the sheet-through discharge roller 46 is driven only during sheet-through discharge, thereby making it possible to stably discharge the sheet-through document. In this embodiment, the transport section 15 and the paper feed section 10
The gap formed between the two is used as a discharge path for sheet-through originals. At least one or more sheet-through discharge rollers 46 are provided between the final end of the discharge path and the final position where the conveying force of the conveyor belt 22 acts, and the sheet-through discharge rollers 46 are arranged so that the electromagnetic clutch is turned off. It is designed to rotate in both forward and reverse directions.

As described above, in this embodiment, the gap formed between the conveyance section 15 and the paper feed section 10 is used as the ejection path for the sheet-through original, and the sheet-through ejection roller for ejecting the sheet-through original is used as the ejection path for the sheet-through original. By rotationally driving 46 in the discharge direction only when discharging a sheet-through document, it is possible to stably discharge the sheet-through document while following the existing device configuration.

Next, the drive system of the transport section 15 will be explained. As shown in FIG. 6, the conveyor drive system includes a conveyor belt motor 60 for driving the conveyor belt 22 and the sheet-through discharge roller 46, and a conveyor belt motor 60 for driving the feed roller 42, reversing drive roller 27, and discharge roller 24. It has a reversing motor 61 for causing the rotation. The conveyor belt 22 and the sheet through discharge roller 46 are driven in the circumferential direction via a timing belt 62, an idler pulley 63, a timing belt 64, and the like. The conveyor belt 22 is wound around a belt drive roller 51 and a belt driven roller 52 and is driven to rotate in both directions. Further, the sheet-through discharge roller 46 is driven only in the discharge direction by a pulley 65 with an electromagnetic clutch as a discharge drive means. Next, feed roller 4
2 and the reversing roller 27 are connected to the double-tooth timing belt 6 after passing through the timing belt 66, idler pulley 67, etc.
8. Furthermore, the timing belt 69
By means of the pulleys 70 and 71 with one-way clutches and the idler gear 72, the discharge roller 24 is driven only in the discharge direction, regardless of the rotational direction of the reversing motor 61.

[0022]Here, the invention recited in claim 3 will be explained. In FIG. 1, a continuous computer paper document (hereinafter referred to as CF paper) is carried in from the upper part of the paper feed section 10 using the sheet-through document discharge path as a carry-in path. After this CF paper is conveyed by the conveyor belt 22 in the same direction as the conveyance direction of the cut sheet original 13 and stopped,
A CF paper exposure control means 53 is provided which exposes the stopped CF paper while moving the exposure means 16. Note that the CF paper transport path is not limited to the embodiment in which the sheet-through document discharge path is commonly used, and may be a dedicated transport path.

As described above, in this embodiment, the CF paper is fed from the upper part of the paper feed section 10 onto the conveyor belt 22, and the CF paper is transported by the conveyor belt 22 in the same direction as the conveyance direction of the cut sheet original 13. After the paper is conveyed one page at a time and stopped, it is exposed to light by an exposure means. Therefore, while taking advantage of the operability and transport reliability of the document transport device, it is possible to support the transport of various types of documents such as cut sheets, sheet-through documents, and CF paper.
The document feeding path can be simplified.

Exposure operations for sheet-through originals (sheet-through mode) and exposure operations for CF paper (CFF mode) will be described below. Sheet-Through Mode This mode is used when copying a document larger than the size of the contact glass 14, for example, A2 or the like. When using the sheet-through mode, the mode is set using an input means (not shown) on the copying machine main body 11 side. Although the description will be made so that the mode is set on the copying machine main body 11 side, this mode may be entered when a sheet-through original is detected by the feed sensor 43 (see FIG. 1) on the ADF side.

A mode setting from the copying machine main body 11
When the DF side recognizes that it is the sheet-through mode, the reversing motor 61 is turned on for a certain period of time by the document detection by the feeding sensor 43, and the sheet-through document is fed so as to come into contact with the entrance gate 44. Since the feed roller 42 makes weak contact with the sheet-through document, even if the sheet-through document hits the entrance gate 44, it will not break, and the sheet-through document will be skewed parallel to the entrance gate 44. Corrected. During this time, on the copying machine main body 11 side, the exposure means 16 is moved to a position approximately at the center of the conveyor belt 22 as described above, and when the movement is completed, the print switch is set to the green state to notify the copying ready state.

When the print switch is pressed in this state, the ADF first moves the entrance gate 44 to the dotted line position according to a command from the copying machine main body 11, and then drives the reversing motor 61, so that the sheet-through original is moved to the reversing registration sensor 80. Transport it until it touches the surface and then stop it temporarily. When a sheet-through document feeding command is received from the copying machine main body 11 at a predetermined timing, the ADF side operates the reversing motor 61 and the conveyance belt motor 6.
0 at an accurate conveyance speed based on the reference clock frequency from the CPU 100 shown in FIG. 9, and conveyance is started. This conveyance speed can be changed by changing the reference clock frequency from the CPU 100. The magnification can be changed by changing the conveyance speed of the sheet-through document and the speed ratio of the imaging section of the copying machine main body 11. The sheet-through document is conveyed at a constant speed while being exposed on the contact glass 14, and the reference side scale 49 and the switching plate 50 are moved to the position indicated by the dashed dot line. Therefore, the sheet-through document is guided upward and is discharged to the CF paper entrance section 54, that is, the upper part of the paper feed section 10, via the sheet-through discharge roller 46.

As shown in FIG. 5, the CF paper entrance section 54
The upper surfaces of the sheet feeding section 10 and the sheet feeding section 10 are at approximately the same height, and a sheet-through document can be ejected without bending. In addition, since the document feed table 41 and the CF paper entrance section 54 are at almost the same height, even when a sheet-through document is placed on the document feed table 41 to feed a sheet-through document, the document can be placed almost flat, and the height of the top surface is almost uniform, giving a clean appearance.

[0028] The operation when making repeat copies of several sheets from one sheet-through original will be described next. The first copying operation is the same as the above operation, but the second operation is performed after the trailing edge of the sheet-through original passes the exposure position in the first copying operation (this detection is performed using the inversion registration sensor 80 in FIG. 1). After the trailing edge of the document has passed, this can be detected by counting the elapsed time or the number of pulses of the conveyor belt motor 60), the conveyor belt motor 60 and the reversing motor 61 are turned in the opposite direction, that is, the cut sheet 13 is conveyed. direction. At the same time, the reversal switching claw 23 and the reversal discharge switching claw 28 are controlled to be at the positions indicated by the dashed-dotted lines. By reversing each operating system, the sheet-through original is picked up by the reversing switching claw 23, driven by the reversing drive roller 27 and the driven roller 45,
It is guided to a reverse discharge guide plate 29 via a reverse discharge switching claw 28 .

When the end surface of the sheet-through document passes the sheet-through sensor 84, the reversing motor 61 performs a reversing operation again, and stops after a predetermined time (or after a predetermined pulse) after turning on the sheet-through sensor 84. At this time, it is desirable that the distance from the end surface position of the sheet-through document to the exposure position is equal to the distance between the exposure position and the document position stopped based on the reversal registration sensor 80 when copying is performed for the first time. As a result, it becomes possible to make the paper feeding timing on the copying machine side the same for the first and second and subsequent times, which facilitates control. Note that in this embodiment, as described above, the first document position and the second and subsequent document positions are controlled to be the same distance from the exposure position, but if this is not possible due to the structure, the timing may be changed. Needless to say, it is also possible to carry out transportation by changing the.

Next, after a predetermined timing, the copying machine main body 1
When the document feeding command comes from 1, the ADF side switches the reversing motor 61 and the conveyance belt motor 60 to C as in the case of the first document.
Conveyance is started at an accurate conveyance speed based on the reference clock from the PU 100. Thereafter, the same operation as for the first sheet is performed, and this operation is repeated for the number of sheets to be repeated. After copying the number of repeat sheets, the sheet-through original is discharged from the CF paper entrance section 54.

As shown in FIG. 7, the CF paper entrance section 54 includes a sensor 81 for detecting the presence or absence of CF paper (hereinafter referred to as CF paper detection sensor) and a sensor for detecting holes in the CF paper (hereinafter referred to as CF paper detection sensor). (referred to as hole detection sensors) 82 are installed side by side. Note that the CF paper detection sensor 81 is
In sheet-through mode, it is used to detect the ejection of sheet-through originals.

Here, as shown in FIG.
It is provided at a distance of 6.35 mm (1/4 inch) from the edge of the original of the F paper 55. On the other hand, the CF paper detection sensor 8
1 is located closer to the manuscript center than that. As shown in the figure, the end surface of the sheet-through document 56 is set to pass approximately in the center of the CF paper detection sensor 81 and the CF paper hole detection sensor 82 . With such a sensor arrangement, it is possible to detect the skew of the original during repeat copying of the sheet-through original 56. That is, when normal conveyance is repeated, the CF paper detection sensor 81 is in the document detection state, and the CF paper hole detection sensor 82 is in the non-detection state. If the sheet-through document 56 is skewed for some reason, both sensors 81
, 82 are simultaneously turned on or turned off. As a result, it is possible to detect skew. In this example, the skew detection width is (1/2) x (
distance between the sensors 81 and 82). Here, when the skew exceeds a predetermined value, the repeat operation is stopped and the sheet-through document 56 is discharged to the upper part of the paper feed section 10. Note that when implementing this configuration, the edge reference of the document differs between sheet-through mode and other modes, but this can be done by moving the lens system of the copying machine to unify the reference position for image formation. It is supposed to be done.

By the way, as shown in FIG. 8, a CF positioning guide 84 for positioning the CF paper 55 in the width direction is provided at the paper discharge port of the sheet-through original 56, that is, at the entrance portion 54 of the CF paper 55. There is. This CF positioning guide 84 is slidably attached to a CF loading guide plate 85 that forms a loading path for CF paper.
When a sheet-through document is ejected, it is moved away from the ejection path. Here, a magnet 86 is attached to the lower part of the CF positioning guide 84, as shown in FIG. Further, a magnetic sensing element 87 is attached below the CF loading guide plate 85, and the magnet 8
By detecting the magnetic force of 6, the CF positioning guide 84
It is designed to detect the position of. Therefore, in the sheet-through mode, if the CF positioning guide 84 is set at a position that does not prevent the ejection of sheet-through originals, conveyance of the sheet-through original is permitted, but if the CF positioning guide 84 is set at a position that prevents ejection of the sheet-through original, In such cases, conveyance of sheet-through originals is prohibited and the user is notified through guidance, etc. As a result, during sheet through, CF
Jams due to improper positioning of the positioning guide 84 can be prevented. CFF mode This mode is used when copying CF paper. Since the control itself of the CFF mode is already known, the details will be omitted. As described above, driving force is input to the sheet-through discharge roller 46 provided in the CF paper carrying path through an electromagnetic clutch so that the sheet-through discharge roller 46 is driven only in the sheet-through discharge direction. For this reason, it is only driven when ejecting through sheets, and when carrying in and transporting CF paper, the CF
Follows the direction of paper movement. As a result, it is possible to achieve both stable ejection of sheet through and conveyance of CF paper.

Now, when copying CF paper, the conveying section 15 is opened, the side edge of the CF paper is positioned by the CF positioning guide 84, and the CF paper is moved to the CF carry-in guide plate 8.
5, set the CF paper on the contact glass 14. In this way, when setting CF paper, set the CF paper so that the fold line of the CF paper is aligned with the document reference. Next, by closing the transport section 15, the CF original is set. The setting of the CF paper is detected by a CF paper detection sensor 81 shown in FIG. By pressing the copying machine's print switch (not shown), a CF paper feed command is sent from the copying machine to the ADF every time copying is completed.
Sent to the side. AD by the feed signal from the copier
F counts the holes in the CF paper using the CF paper hole detection sensor 82, and stops the CF paper when one page is counted. Then, the exposure means is moved to perform an exposure operation, that is, a copy operation. The copied CF paper is discharged to the document tray 25 via the discharge roller 24. In addition, C
A CF positioning guide 84 provided at the FF entrance section presses the end surface of the CF paper to prevent skew.

FIG. 9 is a schematic block diagram showing the overall circuit configuration of the ADF. As shown in the figure, the CPU 10 of the ADF
0 is provided with a sheet-through original exposure control means 47 and a CF paper exposure control means 53. CPU100
is connected to a control device 102 on the copying machine main body side via a transmission/reception buffer 101, and transmits information through serial communication. The CPU 100 drives an input section (input buffer) 103 into which signals from each sensor are input, a paper feed motor 104 that drives the paper feed section 10, a conveyance belt motor 60, a reversing motor 61, and the like. The driving of the three motors is controlled by each servo circuit 105. Each servo circuit 105 has a CP
Motor ON/OFF command from U100, command to control motor speed (for example, 6-bit data input from CPU 100 via D/A converter 106)
, and the motor rotation direction command, the CPU 100
Each motor is operated according to the commands. Here, the speed control of the motor in the servo circuit 105 uses pulses from an encoder 107 attached to the motor. Further, this pulse information is supplied to CPU 100, and CPU 100 mainly controls the position of the document based on this pulse information. Part of the pulse information is also used to detect abnormalities in the motor.

By the way, the CPU 100 has analog ports AN1 and AN2 (for example, NEC's μ
variable resistors VR1 and VR2 are attached to the analog ports AN1 and AN2, respectively. For example, the CPU 10 calculates this resistance value with a resolution of 256 gradations.
0. This information is used to adjust the stopping position of the document, which varies slightly from machine to machine. For example, in a certain machine, after a document passes through the registration sensor 57 in FIG.
Assuming that the number of stop pulses up to the document standard is 640 pulses, the value of VR1 may be changed to reach this number of pulses. On the software, for example, if you set 600 pulses as a fixed value and set it to 600+(VR1 analog value), you can adjust it.

In this embodiment, as can be seen from the above description, the conveyance directions are reversed in the sheet-through mode and the normal mode in which the cut sheet document 13 is conveyed from above the document table 12. This is A in normal scan mode.
This is to shorten the time required to replace originals when cutting sheet originals are fed by the DF. For example, as shown in FIG. 10, when the document reference B is on the left side of the contact glass 14, the exposure means of the main body scans from left to right as indicated by arrow M, and then stops the exposure means of the main body to expose the document. In the sheet-through mode, the document conveyance direction is from right to left as indicated by arrow N. Conversely, in FIG. 11, when the document reference A is on the right side of the contact glass 14, the scanning direction of the exposure means of the main body is from right to left as indicated by arrow M, and the document conveyance direction in sheet-through mode is as indicated by arrow N. from left to right. Here, in the normal scan mode, the document transport direction in the ADF is the same as the transport direction in the sheet-through mode (Fig. 10
, 11 n direction) and the opposite direction (Fig. 10
, 11), there is a difference in the transport span, so there is a difference in the time required to replace the document. In other words, in the same direction n(
When the cut sheet original is transported in the ADF mode (conveying from the direction opposite to the original standards A and B), it takes longer to replace the original.

[0038] Here, using a concrete and simple model, the difference in document replacement time will be explained. The model is shown in Figure 12. The transport speed of the cut sheet original 13 is 1
500 mm/s, the distance from the registration sensor 57 to the document reference A is 110 mm, and the distance from the document reference A to the document reference B is 330 mm. FIG. 13 shows a time chart when an A4 size document is transported in the horizontal direction. The case where the document is stopped at document reference A is shown by a solid line, and the case where the document is stopped at document reference B is shown by a broken line. Assuming that the conveyance belt motor 60 is decelerated linearly for 70 ms, (1) the cut sheet original 13 conveyed in the m direction with the original reference A;
When stopping the document, the time t1 from when the registration sensor 57 turns OFF (at the rear edge of the document) until the document stops is
110mm-(1500mm/s x 70m
s) /2 t1 =────────────
──────+70ms=108ms
1500mm/s
(2) When stopping the cut sheet original 13 conveyed in the n direction using the original standard B, t2 is 110 mm + 330 mm.
-210mm -(1500mm/s ×70ms)
/2 t2 =───
──────────────────────────＋7
0ms
1500mm/s
= 188ms

(A4 width, 210mm), t2 - t1 = 80
There is a difference in document replacement time of ms. Therefore, in order to improve productivity, in the normal scan mode, the cut sheet original 13 is transported in the m direction from the original reference A side, and in the sheet through mode, the original is transported in the direction N, which is opposite to the normal original transport. It is more advantageous to do so.

[0039]

As explained above, according to the electrophotographic apparatus according to the invention as set forth in claim 1, the sheet-through original fed to the original transporting means is transported by the original transporting means to transport the cut sheet original. By exposing the original using an exposure means that is stopped at a predetermined position while moving in the opposite direction, it is possible to expose the original by sheet-through while taking advantage of the operability and transport reliability of the original transporting device.

Further, according to the electrophotographic apparatus according to the second aspect of the invention, the gap formed between the document conveying means and the document feeding means is used as a sheet-through document ejection path, and the sheet-through document is ejected. By rotationally driving the ejection roller in the ejection direction only when ejecting the sheet-through original, it is possible to stably eject the sheet-through original while following the existing device configuration.

Further, according to the electrophotographic apparatus according to the third aspect of the present invention, the ejection passage for sheet-through originals is also used as the carry-in passage for continuous computer paper originals, and the continuous computer paper originals are conveyed one page at a time by the conveying means. By conveying and exposing the document, a conveyance path that can perform both sheet-through discharge and continuous computer paper document conveyance can be constructed, and the document passage path can be simplified while supporting various document conveyances.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of an electrophotographic apparatus according to any one of claims 1 to 3.

FIG. 2 is an enlarged view showing a state when a one-sided document is ejected from the reversing section in FIG. 1;

FIG. 3 is an enlarged view showing a state when a double-sided document is ejected from the reversing section in FIG. 1;

FIG. 4 is a side sectional view showing another embodiment of the reversing section.

FIG. 5 is an enlarged view showing a sheet-through document discharge section and a continuous computer paper document inlet section in FIG. 1;

FIG. 6 is a diagram showing a drive system of the document conveying device.

FIG. 7 is a diagram showing the arrangement positions of a CF paper detection sensor and a CF paper hole detection sensor.

FIG. 8 is a diagram showing a CF positioning guide at the entrance portion of CF paper.

FIG. 9 is a schematic block diagram showing the overall circuit configuration of the document conveying device.

FIG. 10 is a diagram showing the document conveyance direction with respect to the document reference B.

FIG. 11 is a diagram showing the document conveyance direction with respect to the document reference A.

FIG. 12 is a diagram showing a transport model for a cut sheet original.

FIG. 13 is a chart showing transport timing in FIG. 12;

[Explanation of symbols]

10 Paper feeding unit (original feeding means) 13 Cut sheet original 14 Contact glass (original mounting table) 15
Conveyance section (original conveyance means) 16 Exposure means 40 Sheet-through document feeding means 46 Sheet-through discharge roller 47 Sheet-through document exposure control means 53
Continuous computer paper document exposure control means 54
Continuous computer paper document entrance section 56 Sheet-through document 65 Pulley with electromagnetic clutch (discharge drive means)
.

Claims (3)

[Claims] Claim 1: Document feeding means fixedly disposed on an electrophotographic apparatus and feeding out a set cut sheet original, and a document placing table of the electrophotographic apparatus provided adjacent to the document feeding means. A document conveying device having a document conveying means that can be freely opened and closed toward and away and conveying the cut sheet document to the document placing table, and the document conveying device conveys the cut sheet document to a predetermined position on the document placing table. sheet-through document feeding in which a sheet-through document is fed to the document transporting device in an electrophotographic apparatus having an exposure device that exposes the stopped cut-sheet document to light while moving the document; and a sheet-through original exposure control means for exposing the sheet-through original by an exposure means stopped at a predetermined position while moving the sheet-through original by the original transporting means in a direction opposite to the transporting direction of the cut sheet original. An electrophotographic device characterized by: 2. A gap formed between the document transport means and the document feed means is used as a discharge path for the sheet-through document, and from the final end of this discharge path to the final position where the conveyance force of the document transport means acts. Claim 1 characterized in that at least one or more discharge rollers rotatable in both forward and reverse directions are provided between the two, and a discharge drive means is provided for rotationally driving the discharge roller in the discharge direction only when a sheet-through document is discharged. The electrophotographic device described. 3. A continuous computer paper document is carried into the document transport means using a sheet-through document discharge path as a carry-in passage, and the continuous computer paper document carried in through the carry-in passage is conveyed one page at a time by the document conveyance means. 3. An electronic photograph according to claim 2, further comprising an exposure control means for continuous computer paper original, which exposes the stopped continuous computer paper original while moving said exposure means after stopping the continuous computer paper original. Device.