JP3913222B2 - Document feeder - Google Patents

Description

  The present invention relates to a document feeding device that feeds a document onto a platen.

  2. Description of the Related Art Conventionally, in an image forming apparatus having a document feeding device, when a document is fed by the document feeding device and placed at an image reading position, a document image is read by scanning the document at the reading position by a scanner ( Hereinafter, the fixed reading method) is known. In order to achieve 100% productivity of the image forming apparatus by this fixed reading method, the original document is fed by the original feeding device between the end of scanning by the scanner and the return of the scanner to the image reading start position. Must be fed and placed at the image reading position to complete the document exchange.

  To achieve this, the document feeder must feed the document at a high speed. However, if the document is fed at a high speed, the feeding sound in the document feeder increases, and the document Recently, a method of reading an image while fixing a scanner in a predetermined position and feeding a document with a document feeding device (hereinafter referred to as a flow reading method) has been adopted. ing. According to the flow reading method, since the document replacement and the image reading are performed at the same time, there is an advantage that high productivity can be obtained even if the feeding speed is lowered.

  Sink reading is performed by conveying a document along the platen with a wide belt, and image formation starts from the start of driving of the drive motor for driving the wide belt until the vibration of the drive system stops. To avoid this, the transport path is lengthened accordingly. According to this flow reading method, even when the drive motor starts driving, image formation is not started immediately, and as shown in FIG. 46A, after the run-up period (T1) has elapsed, that is, the drive system After the vibration is settled, image formation is started, and after the image formation period (T2) has elapsed, the drive motor is stopped and waits for the waiting period (T3) to receive the next paper feed start signal. This cycle (T0) is repeated.

Japanese Patent Publication No. 8-18728 US Pat. No. 5,407,191 US Pat. No. 5,423,527 U.S. Pat. No. 4,331,328 U.S. Patent No. 4451027 US Pat. No. 4,893,804 US Pat. No. 5,121,915

  However, these prior arts assume that the paper is transported at a high speed, and when the paper interval becomes extremely narrow, the speed of the subsequent paper is reduced or the paper interval is inappropriate. Is to control the speed on the downstream side of the conveyance path and adjust the sheet interval. Such a prior art, for example, sequentially separates the documents stacked on the tray of the document feeder, When applying to an image forming apparatus that reads an image while conveying a document on a scanner that is fixed to (hereinafter referred to as “flow reading”), there are the following problems.

  That is, when the original on the original tray is continuously separated and transported with the original interval being narrowed, the original cannot be sufficiently separated and the preceding paper and the subsequent original are carried along. This phenomenon is prominent when the original is a paper having a large surface friction coefficient such as recycled paper. In order to solve this problem, there is no choice but to apply the above-mentioned prior art because feeding is performed with a sufficient separation interval.

  Further, in order to correct the paper interval, a method of controlling the conveyance speed is adopted, and the speed response at the time of acceleration / deceleration is not sufficiently considered, and there is a difficulty in controlling the paper interval with high accuracy. . In order to improve this, there is a method of simultaneously controlling the speed and the moving amount by using a stepping motor, but not only the calculation processing for correcting the document interval is complicated, but also there is a load fluctuation like separation driving. There was a risk of stepping out in large transport systems.

  Further, when trying to control the paper interval on the downstream side of the conveyance path, it is necessary to make the distance between the separation unit and the original image reading unit sufficiently large. There was a problem that the number of times of reading the original was not increased. Furthermore, when trying to correct the sheet interval near the image reading unit, the vibration affects the image reading, resulting in a problem that the read image quality is impaired.

  An object of the present invention is to provide a document feeding device that can solve the above-described problems and can further improve the accuracy of the distance between sheets.

The invention according to claim 1 is a document feeding device that feeds a document to a reading position of the image reading device, and separates the stacked plurality of documents one by one, and is separated by the separation unit. A first feeding means for feeding the original, a second feeding means provided on the downstream side of the first feeding means, and the reading position provided on the downstream side of the second feeding means. In a document feeder having a transport means for transporting a plurality of documents ,
Before the leading edge of the succeeding document fed by the first feeding means enters the second feeding means, the distance between the preceding document and the preceding document preceding the succeeding document is previously set. Control means for controlling the rotational speed of the first feeding means according to a difference from the determined inter-paper distance, and the control means further pushes the leading edge of the succeeding document against the second feeding means. After the control so that the distance between the preceding document and the succeeding document is the first distance, the distance between the preceding document and the succeeding document becomes a second distance longer than the first distance. In this manner, the rotational speed of the second feeding unit is controlled, and the preceding document and the subsequent document are conveyed by the conveying unit while maintaining the second distance .

According to claim 1, before Symbol control means includes clock generating means for generating a number of clocks corresponding to the rotational speed of the first motor for driving said separating means and said first feeding means, said first A reference clock generating means for controlling the rotation speed of the second motor for driving the two feeding means, and a succeeding original after the trailing edge of the preceding original is detected at a predetermined position before the first feeding means. The difference between the number of clocks generated by the reference clock generation means and the number of clocks corresponding to a predetermined interval between papers according to the size of the conveyed document is detected until the leading edge of the document is detected. arithmetic means, the difference calculated by said difference calculating means is preset, to the preset simultaneously, with counts up the reference clock generated by the reference clock generating means, said clock production And a up-down counter that counts down the number of pulses generated by the means, the count value of the up-down counter so that the zero, drives and controls the rotational speed of the first motor in accordance with the count value It is characterized by that .

According to claim 2, wherein the control means, wherein also continue, the rotational speed of the first motor control Gosuru it to the count value to zero after a count value of said up-down counter becomes zero And

According to claim 1, wherein, while the original is conveyed across the second feeding means and the first feeding means, the feeding speed of the first feeding means, said second sheet and controls to match the feeding speed of the feeding means.

  According to this invention, since it comprised as mentioned above, the precision of the distance between sheets can be improved more.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 27 shows a first embodiment of the present invention. This is an example of a copying machine, and an ADF (auto document feeder) 2 is provided on the copying machine main body 1. The structure of this copying machine is shown in FIG.

  Referring to FIG. In an ADF (auto document feeder) 2, a wide belt 7 wound around a driving roller 36 and a turn roller 37 is disposed below the document tray 4. On the document tray 4, the document P is placed in the order of 1 page (2 pages), 3 pages (4 pages),. The document P on the document tray 4 is sequentially separated from the uppermost sheet, and is conveyed to a platen glass (hereinafter referred to as a platen) 3 that is a reading position of the copying machine main body 1. The wide belt 7 is in contact with the platen 3, and the sheet document P conveyed from the document tray 4 is placed at a predetermined position on the platen 3, or the sorted document P on the platen 3 is placed on the discharge tray 10. To be taken out.

  The copier body 1 will be described. The copying machine main body 1 includes a reader unit 200 and a printer unit 300. The reader unit 200 optically reads image information recorded on the document P placed on the platen 3, photoelectrically converts it, and inputs it as image data. The scanner unit 204 includes a platen 3, a lamp 202, and a mirror 203, mirrors 205 and 206, a lens 207, and an image sensor 208. The printer unit 300 forms an image by a known method, and its structure will be described later.

  The present invention can also be applied to a reading device in which the reader unit 200 and the document feeding device are integrated. The present invention can also be applied to a copying machine having a main body provided with a document feeding device.

  The printer unit 300 will be described with reference to FIG. In FIG. 2, reference numeral 400 denotes an upper cassette and a sheet material. Reference numeral 401 denotes a feeding roller for feeding the sheet separated from the upper cassette 400 by the separation claw to the registration roller 406. Reference numeral 402 denotes a lower cassette for storing a sheet material. Reference numeral 403 denotes a feeding roller for feeding the sheet separated from the lower cassette 400 by the separation claw to the registration roller 406. Reference numeral 404 denotes a manual feed guide for guiding the sheet material set on the manual document tray to the registration roller 406 via the roller 405 one by one. Reference numeral 408 denotes a deck type sheet stacking device, in which a sheet material is placed on an intermediate plate 408a, and the intermediate plate 408a can be moved up and down by a motor or the like. Reference numeral 409 denotes a feeding roller for feeding the uppermost sheet material separated by the separation claw among the plurality of sheet materials placed on the intermediate plate 408 a to the registration roller 406 via the conveying roller 410. is there.

  Reference numeral 412 denotes a photosensitive drum for forming a latent image based on image data. A developing device 414 develops a latent image on the photosensitive drum 412 to form a toner image. A transfer charger 415 transfers a toner image on the photosensitive drum 412 onto a sheet material fed by the registration roller 406 at an appropriate timing. A separation charger 416 is for separating the sheet material on which the toner image is transferred.

  Reference numeral 417 denotes a conveyance belt for conveying the sheet material on which the toner image is transferred. A fixing device 418 fixes the toner image on the sheet material conveyed by the conveying belt 417. Reference numeral 419 denotes a conveyance roller for conveying the sheet material after fixing. Reference numeral 420 denotes a flapper that regulates the conveyance path of the sheet material conveyed by the conveyance roller 419. Reference numeral 421 denotes a discharge roller, which transports the sheet material regulated by the flapper 420 in the transport path to the discharge roller 421 to the sorter 422 via either the non-sort tray discharge roller 422c or the sort bin tray discharge roller 422d. Is for. The sorter 422 includes a non-sort tray 422a and a sort bin tray 422b for receiving the discharged sheet material. A non-sort tray discharge roller 422c is provided on the non-sort tray 422a, and a sort bin is provided on the sort bin tray 422b. The sheet material is discharged by the tray discharge roller 422d. The non-sort tray 422a and the sort bin tray 422b are moved up and down to sort the sheet material. Of course, instead of the sorter 422, a discharge tray can be mounted.

  Reference numeral 500 denotes an intermediate tray for stocking the sheet material on which the image is formed when images are formed on both sides of the sheet material, or when an image is formed on one side of the sheet material (multiple). Is. Reference numeral 501 denotes a conveyance roller for conveying a sheet material regulated by a flapper 420 on a conveyance path to the conveyance roller 501. A conveyance belt 502 conveys the sheet material conveyed by the conveyance roller 501 with the image surface facing down. A flapper 503 is provided downstream of the conveyance belt 502. The sheet material conveyed by the conveyance belt 502 is restricted to a path 507 to the intermediate tray 500 in the case of multiple copying, and on the conveyance belt 504 in the case of duplex copying. And the reverse path 506 downstream of this path. The sheet material conveyed onto the intermediate tray 500 via the path 507 is stacked on the intermediate tray 500 with the image surface facing down. Reference numeral 505 denotes a conveyance roller for conveying the sheet material conveyed through the reverse path 506 onto the intermediate tray 500. The sheet material conveyed onto the intermediate tray 500 by the conveying roller 505 is stacked on the intermediate tray 500 with the image surface facing up.

  509 and 510 are auxiliary rollers, and 511 is a pair of forward and reverse separating rollers. These rollers cooperate to separate the sheet material stacked on the intermediate tray 500 one by one from below, and the separated sheet material. For re-feeding. Reference numerals 513, 514, and 515 denote conveyance rollers for feeding the sheet material separated from the intermediate tray 500 and re-fed to the roller 110.

  In addition, according to the method of creating only one set of copies each time a document is made one round by the automatic document feeder, even when a plurality of copies are created, a group of copies with pages is obtained in order. Even if there is no sorter, the required number of copies can be divided and obtained.

When double-sided copying is performed by this method, a double-sided copy group can be obtained by repeating a cycle in which both sides of a single document are continuously read and continuously copied and discharged on the front and back sides of the sheet material.
[Description of Configuration of Document Tray 4]
The pair of width direction regulating plates provided on the document tray 4 are slidable in the width direction of the sheet document P, regulate the width direction of the sheet document P placed on the document tray 4, and This ensures stability during feeding. The stopper 21 (FIG. 4) is rotatably disposed at the end of the document tray 4, and the stopper 21 protrudes to restrict the sheet document P set on the document tray 4 from moving downstream. Is.
[Description of sensor on tray]
In the vicinity of the upstream portion of the stopper 21, document set detection sensors 40 a and 40 b (FIG. 4) that are transmissive optical sensors that detect that a sheet document P bundle has been set are provided. In the middle of the document tray 4, there is provided a document trailing edge detection sensor 41 which is a reflection type optical sensor for determining whether or not the set document is a half-size document. The document trailing edge detection sensor 41 is disposed at a position 225 mm away from the stopper 21 and is turned on when a longitudinal document is set. A final document detection sensor 43, which is a reflection type optical sensor, is provided at an intermediate portion between the document set detection sensor 40 and the trailing edge detection sensor 41 so that it can be determined whether or not the document being conveyed is the final document. It has become. A paper width detection sensor 44 that detects the length in the width direction of the bundle of documents P set on the document tray 4 by detecting the position of the width direction regulating plate is provided below the document tray 4.
[Description of separation unit]
A swing arm 53 (FIG. 5) is provided above the document tray 4. The elevating arm 51 swings with respect to the rotation width center c1 of the separation feeding roller 8, and the arm shaft 51c is supported through the support plates 51a, 51b before and after the elevating arm 51, The swing arm 53 is controlled to swing by the arm shaft 51c. A paper feed roller 5 is provided at the tip of the swing arm 53. Normally, the position of the paper feed roller 5 shown in FIG. 5 is the home position, and is restrained by the arm shaft 51c and retracted above the upper separation guide plate 52 (suppressed by the bin 51g). Therefore, the document setting work is not hindered. The elevating arm 51 is driven and controlled by a motor 103 which will be described later, and is in the position shown in FIG.

  FIG. 9 is a plan view of the separation unit. The lifting / lowering arm 51 rotates about the rotation axis center C1 and is movable from the position of FIG. 5 to the position of FIG. As described above, the paper feed roller 5 is provided at the tip of the swing arms 57 and 53 that rotate about the rotation center axis C1. The swing arms 57 and 53 are lowered by their own weight as the elevating arm 51 is moved, and stop when the paper feed roller 5 is landed on the uppermost sheet of the document P. This state is shown in FIG. When the paper feed roller 5 is rotated in this state, the original can be sequentially conveyed from the uppermost paper. The upper guide plate 52 is restrained to the position shown in FIG. 6 by a stopper (not shown).

  At the point where the sheet feeding roller 5 has landed on the uppermost sheet of the sheet document bundle, that is, in the state of FIG. 8, the relationship between the swinging arms 57 and 53 and the arm shaft 51c supporting the swinging arms 57 and 53. The match is released. At this time, the relative positional relationship between the swing arms 57 and 53 and the lifting arm 51 starts to shift. The amount of deviation is based on the first swing arm flag 54 and the second swing arm flag 55 which are a part of the swing arms 57 and 53, and the first swing position sensor 46 and the second swing arm 51 attached to the lifting arm 51. By the position sensor 47, the non-detection state so far becomes the detection state of FIG. 8, and the swing arms 57 and 53 are controlled to stop.

  In this state, the swing arms 57 and 53 and the paper feed roller 5 are placed in a self-loading state with respect to the bundle of sheet originals P stacked on the tray 4, and a stable feeding force is always applied to the sheet original P. It becomes possible to grant.

  The elevating arm 51 is driven by a swing motor 103 (stepping motor), and the elevating arm 51 can take an arbitrary position between the position shown in FIG. 5 and the position shown in FIG. 6 (for example, the position shown in FIG. 7). Is possible.

  A paper feed roller home sensor 45 that is a transmissive optical sensor is attached to the fixed support plate 56 above the separation portion. When the lifting arm 51 is positioned at the standby position that is the home position, the swing arms 57 and 53 are arranged. The raising / lowering arm flag 51d provided on the sensor block shields the sensor optical path of the paper feed roller home sensor 45.

  As described above, the lift arm 51 is provided with the first swing position sensor 46 and the second swing sensor 47 that move integrally with the lift arm, and the first swing position sensor 46 and the second swing sensor 47 The first swing arm flag 54 and the second swing arm flag 55 formed so as to extend in the descending direction of the swing arms 53 and 57 can be detected.

  In the state of FIG. 7, as described above, the feed roller 5 is in the retracted position during continuous feeding, and the swing arms 57 and 53 do not need to return to the home position (the state of FIG. 5). The sheet feed roller 5 is controlled to stop at an intermediate position at a position separated by a minimum amount (about 3 mm to 5 mm).

  By adopting such a configuration, it becomes possible to minimize the amount of movement of the paper feed roller 5, and the landing vibration of the paper feed roller 5 on the sheet original P is reduced, thereby improving the paper feed performance. Contribute. At the same time, it is possible to shorten the time until the start of the subsequent sheet feeding, and it is possible to perform sheet feeding control with a shortened sheet feeding interval.

  When the feeding operation is started when the paper feeding rollers 5 provided on the swing arms 57 and 53 respectively land on the sheet original P and bounce due to the impact, the feeding rollers provided on the swing arms 57 and 53, respectively. The pressure balance with respect to the sheet original P of the paper roller 5 is lost, and the possibility of causing skew during paper feeding increases.

  As shown in FIG. 9, a plurality of paper feed rollers 5 arranged in the width direction each have an independent suspension configuration and are easily equalized into a bundle of sheet originals P, so that the paper feed performance can be improved. Is possible.

  A separation unit including a known separation belt 6 and separation conveyance roller 8 is provided downstream of the shutter 21 in the conveyance direction, and performs a separation operation by rotating in the direction of an arrow (FIG. 8).

The arrangement of the sheet feeding roller 5 and the separation conveying roller 8 is shown in FIG.
[Description of transport path]
The conveyance path will be described with reference to FIG. From the document tray 4 to the platen 3, document feeding paths (A), (B), and (C) are provided in this order. In order to guide the sheet document P onto the platen 3, the document feed paths (A), (B), and (C) are bent (curved downward) and connected to the conveyance path (D) on the platen 3. . Before the document is conveyed to the platen 3, the reverse feeding paths (H), (H), and (R) are extended from the original feeding path (B) so that the original can be reversed. The document reversed in the reverse feeding paths (h), (f), and (re) is switched back, passed through the document feeding / discharging path (e), conveyed to the platen 3 and placed. A document reversing path (g) is branched from the reversing feeding path (f) so as to be merged with the document feeding path (b), and the document on the platen 3 is transferred to the transport path (e), (f), It is possible to switch back and reverse by using (g) and (c) and to return to the platen 3 again.

  The original on the platen 3 is discharged to the paper discharge tray 10 through the original feed path (d) on the platen and the original discharge path (n) in FIG.

As shown in FIG. 1, an openable manual document tray 14 is provided on the right side of the ADF 2, and the set document P (one document) can be fed to the platen 3 through the manual conveyance path (L). It is like that.
[Explanation of roller arrangement]
The arrangement of the rollers will be described with reference to FIG. The document feed path (A) is a transport path through which the document separated by the sheet feed roller 5 is conveyed in the downstream direction by the separation feed roller 8 and the separation belt 6. Between the document feeding path (A) and the document feeding path (B), there is a roller for restraining the document that is separated and fed by the separation unit, and prevents skewing of the document at the separation unit. A first feed roller 16 is provided for this purpose. The separation feeding roller 8 has a one-way mechanism in order to reduce the transport load when the original is pulled out from the separation unit by the first feeding roller 16.

  A loop is formed in the arrived sheet original P at the junction of the original feeding path (b) and the original reversing path (g) and at the branch of the original feeding path (c) and the reverse feeding path (g). A second feed roller 9 for preventing the sheet document P from skewing is provided. A first reversing roller 17 for conveying the original P along the loop-shaped reversing path is provided between the reversing feeding paths (h) and (f). 2), a second reversing roller 18 is provided for transporting the original P along the loop-shaped reversing path.

  On the right side of the ADF 2 (FIG. 1), a manual paper feed roller 13 is provided for feeding a document set on the manual document tray 14 from right to left in FIG.

  Between the manual feed roller 13 and the platen 3, there is provided a manual registration roller 11 for forming a loop on the manually fed document and preventing skewing. This manual registration roller 11 also relays the document discharge from the platen 3.

In the document discharge path (n) shown in FIG. 1, a discharge roller 12 for discharging the discharged document P to the discharge tray 10 is provided.
[Explanation of flapper in path]
The flapper on the document feeding path will be described with reference to FIGS. A reverse feed flapper 22 for switching the original to either the original feed path (c) or the reverse feed path (h) is provided downstream of the second feed roller 9 in the feed direction. When the reverse feed flapper 22 is positioned at a position indicated by a solid line in FIG. 4, the document P is fed to the reverse feed paths (h), (f), and (re), and FIG. Is fed to the document feed paths (c) and (d).

  The path is switched between the reverse feed path (re) and the original reverse path (g) downstream of the second reverse roller 18 disposed between the reverse feed paths (f) and (re). An inversion flapper 23 is provided. By positioning the reverse flapper 23 at the position indicated by the solid line in FIG. 4, the original P conveyed from the original feed path (b) and the reverse feed path (h) can be reversed. , The original from the platen 3 can be reversed through the original feed / discharge path (e), the reverse feed path (f), and the original reverse path (g).

  A mylar or the like is pasted in the vicinity of the upstream of the first reverse roller 17 disposed between the junction of the reverse feed path (h) and the document feed / discharge path (e) and the reverse feed path (f). A direction flapper 24 is provided. The one-way flapper 24 serves as a guide when the original P is fed from the reverse feeding path (h) to the reverse feeding path (to), and the original P is fed to the reverse feeding path (g), In the case where the document P is fed onto the platen 3 through the document feed / discharge path (e), it plays the role of preventing the reverse entry of the document P into the reverse feed path (h).

  A supply / discharge flapper 25 is provided on the platen 3 side of the document supply / discharge path (e). The feeding / discharging flapper 25 is adapted to be linked with a reverse feeding flapper 22 provided downstream in the feeding direction of the second feeding roller 9, and feeds the document P to the platen 3 from the document feeding / discharging path (e). In the case of feeding, the front end of the original P entering the platen 3 is prevented from colliding with the end of the platen 3 at a position indicated by a solid line in FIG. In the case of feeding from the document to the document supply / discharge path (e), the document is positioned at a position indicated by a one-dot chain line in FIG. 4 so that the document from the platen 3 can be skimmed.

  A paper discharge flapper 26 is provided between the right end of the platen 3 and the manual registration roller 11, and this paper discharge flapper 26 is shown in FIG. 4 when the document P is transported from the manual transport path (L) to the platen 3. The leading end of the document P entering the platen 3 is prevented from colliding with the end of the platen 3, and the document P is discharged from the platen 3 to the document discharge path (n). 4 is positioned at the position indicated by the alternate long and short dash line in FIG. 4 so that the document from the platen 3 can be skimmed.

  A unidirectional direction for preventing the document P discharged from the platen 3 from entering the manual feed path (L) at the junction between the original discharge path (N) and the manual feed path (L) shown in FIG. A manual flapper 27 is provided.

A manual shutter 28 is provided in the vicinity of the downstream of the manual feed roller 13 (FIG. 1) in the paper feeding direction, and this manual shutter 28 is a manual feed set on the manual document tray 14 while the copied document P is being discharged. The original is prevented from entering the manual registration roller. Since the manual feed roller 13 is set to have a low conveying force, the document hitting the manual feed shutter 28 in the lowered state slips by the manual feed roller 13.
[Explanation of sensor placement in path]
The in-path sensor will be described with reference to FIG. Between the separation feeding roller 8 and the first feeding roller 16, a separation sensor 30 which is a transmission type optical sensor for detecting the document P conveyed by the separation feeding roller 8 is provided. The skew detection sensor 31, which is a transmission type sensor for detecting the skew amount of the document P in cooperation with the sensor 30, is at the same position in the transport direction as the separation sensor 30 and is separated by a predetermined distance in the thrust direction. At the position.

  Near the downstream of the first feed roller 16 is a mixed loading detection sensor 32 for detecting the document P by moving the flag. The document tray 4 cooperates with the sensor on the document tray 4 during document transportation. A mixed loading detection sensor 32 is provided for detecting whether or not originals of different sizes are set on the upper side.

  In the vicinity of the upstream side of the second feeding roller 9, a front end and a rear end of the document P that has passed through one of the document feeding paths (B), (C) or the document reversing path (G) are detected. A paper feed sensor 35 which is a transmissive optical sensor is provided. A registration sensor 39, which is a transmissive optical sensor for detecting the trailing edge of the document P, is provided downstream of the second feeding roller 9. When the trailing edge of the document P is detected by the registration sensor 39, the stop position of the document P is controlled.

  A reverse sensor 50 that is a transmission type optical sensor for detecting the original P discharged from the platen 3 or the original P entering the platen 3 is provided in the reverse conveyance path (e).

  The reverse feed path (Li) is a reverse detection sensor 33 that detects the document P by moving the flag, and detects whether or not the document P has been guided to the reverse feed path (Li) by switching the reverse flapper. A reversal detection sensor 33 is provided.

  Near the downstream in the paper discharge direction of the manual registration roller 11, transmission light for detecting the original from the manual feed path (L) and for detecting the original P discharged from the platen 3 to the original discharge path (N). A manual registration sensor 34 as a sensor is provided.

On the manual document tray 14 side of the manual paper feed roller 13, there is a manual document detection sensor 60 for detecting the document P by moving the flag, and a manual document for detecting whether a document is set on the manual document tray 14 or not. A detection sensor 60 is provided.
[Description of drive system]
A drive system of the ADF 2 will be described with reference to FIG. In FIG. 4, reference numeral 100 denotes a separation motor, and a DC brush motor that is PLL-controlled is used. A clock plate 100a made up of a plurality of slits is provided on the motor shaft of the separation motor 100. While the separation motor 100 is rotating, the slit and the separation clock sensor 100b, which is a transmissive optical sensor, are used to drive the motor. Clock pulses proportional to the number of revolutions are generated. The separation motor 100 drives the separation feeding roller 8 and the separation belt 6 of the separation unit in a direction indicated by an arrow in FIG. 4, and transmits a driving force to the sheet feeding roller 5 via the separation clutch 106. .

  Reference numeral 101 denotes a conveyance motor that can rotate forward and backward, and a stepping motor is used. The conveyance motor 101 drives the second feeding roller 9, the first reverse roller 17, and the second reverse roller 18. A clock plate 10la composed of a plurality of slits is provided on the driven roller shaft of the second feeding roller 9, and while the conveyance motor 101 is rotating, the slit and the reverse clock sensor 10lb that is a transmission type optical sensor are provided. And a clock pulse is generated. If slip occurs while the original P is being transported by the second feed roller 9, the slip amount can be measured from the number of generated clock pulses and the number of drive clocks of the transport motor 101. ing.

102 is a reversible base Rutomota, a stepping motor is used. The belt motor 102 drives a driving roller 36 for driving the wide belt 7, and the rotation of the driving roller 36 is transmitted to the turn roller 37 by the wide belt 7. The rotation of the turn roller 37 is transmitted to the manual registration roller 11, and the conveyance speed of the document on the platen 3 is made equal to the conveyance speed of the manual registration roller 11.

  Reference numeral 103 denotes a swing motor that can be rotated forward and backward, and a stepping motor is used to drive the lifting arm 53 of the paper feed roller.

  Reference numeral 104 denotes a paper discharge motor, which uses an FG servo-controlled DC motor. A clock plate 104a composed of a plurality of slits is provided on the shaft of the paper discharge motor 104. While the paper discharge motor 104 is rotating, a slit and a paper discharge clock sensor 104b which is a transmission type optical sensor Clock pulses proportional to the motor speed are generated. The drive of the paper discharge motor 104 is transmitted to the paper discharge roller 12 and the manual paper supply roller 13.

  A stopper solenoid 105 drives the stopper 21 at the paper feed end of the document tray 4. The stopper 21 is in a position indicated by a solid line in FIG. 4 when it is off, and is in a position indicated by a dashed line in FIG. 4 when it is on. A separation clutch 106 transmits the driving force of the separation motor 100 to the sheet feeding roller 5, the separation belt 6, and the separation feeding roller 8. Reference numeral 107 denotes a path switching solenoid that drives the reverse feed flapper 22 and the supply / discharge flapper 25. When the path switching solenoid 107 is off, the reverse feed flapper 22 and the supply / discharge flapper 25 are in the positions indicated by the solid lines in FIG. 4, while when the solenoid is on, the reverse feed is performed. The flapper 22 and the supply / discharge flapper 25 are in the positions indicated by the one-dot chain line in FIG. Reference numeral 108 denotes a reverse flapper solenoid that drives the reverse flapper 23. When the reverse flapper solenoid is off, the reverse flapper 23 is in the position indicated by the solid line in FIG. 4, and when it is on, it is at the position indicated by the alternate long and short dash line in FIG.

A paper discharge flapper solenoid 109 drives the paper discharge flapper 26 and the manual shutter 28. When the paper discharge flapper solenoid is off, the paper discharge flapper 26 and the manual shutter 28 are in the positions indicated by the alternate long and short dash lines in FIG. 4, and when they are on, they are in the positions indicated by the solid lines in FIG. .
[Description of reading position]
FIG. 11 shows a document reading position on the platen 3. The document reading position is switched to one of the reading positions indicated by R1, R2, and R3 in FIG. 11 according to the document transport mode and the transported document size.

  The reading position R1 is a reading position in the duplex original mode. In the double-sided original mode, the original is placed with the end of the original aligned at the reading position R1, and the image is read by scanning the scanner of the copying machine main body 1 (fixed reading mode). The reading position R2 is a reading position of a half-size document in the single-sided document mode. When the reading position is the reading position R2, the scanner of the copying machine main body 1 is fixed, and image reading is performed while transporting a half-size document (flow talk mode).

  The reading position R3 is a reading position for a large-size document in the single-sided document mode and a half-size document that is vertically fed. When the reading position is the reading position R3, the scanner of the copying machine main body 1 is fixed, and image reading is performed while conveying the original (a flow reading mode).

  In FIG. 11, L1 is the distance from the nip point of the second feeding roller 9 to the reading position R1, L2 is the distance from the nip point of the second feeding roller 9 to the reading position R2, and L3 is the second feeding. This is the distance from the nip point of the roller 9 to the reading position R3.

In FIG. 12, L4 is the distance from the leading edge of the subsequent half-size document that has stopped at the standby position on the platen 3 for standby to the reading position R1. L5 is the distance from the leading edge of the document stopped at the standby position to the reading position R2. L6 is the distance from the trailing edge of the preceding document to the previous end of the succeeding original (paper distance). L7 is the distance from the reading position R1 to the manual registration roller 11.

  The stop position of a half-size document is Lph when the length in the conveyance direction of the half-size document is Lph.

L7 <(L4 + 2 × L6 + Lph)
L2> (L5 + Lph)
Therefore, the original Pn is stopped for waiting, and the original Pn-1 is stopped after the image formation is completed, so that the original Pn and the original Pn-1 have a positional relationship as shown in FIG. Even so, as shown in FIG. 12, the trailing edge of the preceding document Pn-12 passes through the nip of the manual registration roller 11, and the trailing edge of the document Pn passes through the nip of the second feeding roller 9. Become. The operation of the ADF will be described next.
[Description of document separation operation]
When a document bundle on the document tray 4 is detected by the document set sensor 40 shown in FIG. 1, the pre-separation operation is started, and the paper feed roller 5 is lowered to land on the document bundle. After that, when the operation unit of the copying machine is operated to input copying conditions and the start key is pressed, the document size is detected by a sensor on the platen 3. When the stopper 21 is sucked by SL, the path of the sheet original bundle is released, and the original bundle is fed by the paper supply roller 5 and advances from the original P1, which is the uppermost paper, to the downstream portion. In the following description, the documents stacked on the document tray 4 are the document P1, the document P2, the document P3,... In order from the top. .

  The separation feeding roller 8 and the separation belt 6 constituting the separation unit, which are arranged downstream of the stopper 21, are rotated in the direction of the arrows, respectively, so that the documents P that have advanced from the document tray 4 are separated one by one. Then, it is conveyed further downstream. The document P that has passed through the separation unit is detected by the separation sensor 30 and the skew sensor 31, and then is restrained and conveyed by the first feeding roller 16. Then, the paper feed roller 5 is raised, and then the separation clutch 106 is turned off. As a result, the drive of the separation belt 6 and the separation feeding roller 8 is disconnected, and the separation belt 6 stops, but the separation feeding roller 8 Is constituted by a one-way roller, and rotates (follows) following the movement of the document P being conveyed.

Thereafter, the document P is conveyed only by the first feeding roller 16 and is abutted against the second feeding roller 9 whose rotation is stopped, and the known skew feeding is performed. After the skew feeding is completed, the first feeding roller 16 and the second feeding roller 9 start to rotate at the same time, so that the first feeding roller 16 and the second feeding roller 9 have the same conveying speed. Synchronous speed control. Since the subsequent operation differs depending on the document conveyance mode, the operation will be described for each document conveyance mode.
[Operation in half-size single-sided document transport mode]
13 and 14 show the flow of the original in the single-side original conveyance mode. When the document transport mode is set to the single-sided document transport mode, the path switching solenoid 107 is turned off, and the transport path is the document feed path (C) (FIG. 3). Accordingly, the document conveyed by the first feeding roller 16 and the second feeding roller 9 enters the platen 3 via the document feeding path (C).

  The conveying speed of the wide belt 7 immediately before the original P1 enters the platen 3 is controlled so as to coincide with the speed of the second feeding roller 9. Then, when the trailing edge of the document P1 passes the nip point of the paper feed roller 5, the feed roller 5 is lowered again to prepare for the subsequent paper feed operation of the document P2. Then, when the trailing edge of the document P1 passes through the nip point of the first paper feed roller 5, the separation clutch 106 is turned on, the paper feed roller 5 starts feeding the document P2, and the second transport roller 9 is turned on. Stopped. This state is shown in FIG.

  The succeeding document P2 is rapidly accelerated after feeding by the feeding roller 5, and is controlled so as to arrive at the feeding sensor 35 when the rotation of the second transport roller 9 is stopped. Then, when the document P2 is detected by the paper feed sensor 35, the first feeding roller 16 and the second feeding roller 9 perform control for skew feeding as in the case of the document P1 preceding the document P2. Is called. At this time, the preceding document P1 enters the transport path (d) on the platen 3 and is independently transported by the wide belt 7. Then, the document P1 is temporarily stopped from being conveyed by the wide belt 7 after a predetermined distance has passed after the trailing edge of the document P1 has passed through the paper feed sensor 35. At the same time as the stop, a conveyance completion signal 120 is output to the copying machine main body, and it waits for the conveyance start signal 121 to be input. The distance between the leading edge of the stopped document P1 and the reading position R2 is L5, and the distance between the trailing edge of the stopped document P1 and the nip point of the second feeding roller 9 is L8. L8 is the distance from the reading position R2 to the second feeding roller 9 when L2 is

L8 = L2- (L5 + conveyance original size)
It is expressed. Since L8 becomes positive, the trailing edge of the stopped document P1 passes through the nip point of the second feeding roller 9. This state is shown in FIG.

  When the conveyance start signal 121 is received from the copying machine main body and the skew feeding control of the succeeding document P2 by the first feeding roller 16 and the second feeding roller 9 is completed, the wide belt 7 is activated, and the preceding belt The original P1 is conveyed at the image forming speed. When the distance from the trailing edge of the preceding document P1 to the leading edge of the succeeding document P2 (hereinafter referred to as the inter-paper distance) reaches a predetermined distance, the second feeding roller 9 is activated, and the second feeding roller 9 causes the succeeding document 9 to move. The conveyance of P2 is started. When the transport speed (image forming speed) of the preceding document P1 by the wide belt 7 and the transport speed of the second feed roller 9 coincide with each other, the second feed roller 9 controls the speed so that the inter-paper distance becomes L6. Is done. When the preceding document P1 reaches the reading position R2, the image destination arrival signal 122 is output, and the copier body 1 that has received the image destination arrival signal 122 starts reading the image of the preceding document P1.

  FIG. 13C shows a state after the image reading of the preceding document P1 is completed. As in the case of the preceding document P1, the succeeding document P2 is temporarily stopped from being conveyed by the wide belt 7 after the trailing edge of the succeeding document P2 has passed through the paper feed sensor 35 and then advanced by a predetermined distance. Even if the reading of P1 is finished, it is stopped after being conveyed for a predetermined time. As can be seen from FIG. 13C, the distance traveled by the preceding document that has been read is L9, and the stop position of the subsequent document P2 is a position at a distance L5 from the reading position R2. In a state where the conveyance by the wide belt 7 is stopped, the document P3 further following the document P2 stands by while maintaining a loop for skew feeding by the second feeding roller 9. When a conveyance start signal 120 is input from the copying machine main body 1 in this state, image formation of the original P2 is started this time.

  FIG. 14A shows the positions of the originals P1, P2, and P3 in the path during image reading of the original P2. During image reading of the document P2, the preceding document P1 is conveyed by the wide belt 7, the manual registration roller 11, and the paper discharge roller 12, as can be seen from FIG. Although the conveyance speed of the wide belt 7 and the manual registration roller 11 is equal, the paper discharge roller 12 is controlled at the same speed as the conveyance speed of the wide belt 7 and the manual registration roller 11 or slightly faster.

  FIG. 14B shows a state when the reading of the subsequent document P2 is completed. When reading of the original P2 is completed, the conveyance of the originals P2 and P3 by the wide belt 7 is temporarily stopped in the same manner as in the case of the originals P1 and P2, and the originals P2 and P3 are temporarily stopped on the platen 3. . However, at this time, the trailing edge of the preceding document P1 has already passed through the nip point of the manual registration roller 11 and is conveyed alone by the paper discharge roller 12. The preceding original P1 is then discharged to the paper discharge tray 10.

  With reference to FIG. 43, the conveyance speed control of the wide belt 7 and the feeding speed control of the second feeding roller 9 will be described. The time transition of the conveyance speed of the wide belt 7 is as indicated by 601 in FIG. 43A, and after the conveyance speed is once accelerated to a speed V2 higher than the image forming speed V1 between time t1 and time t3. Then, the image forming speed V1 is restored, and thereafter the image forming speed V1 is maintained.

  The time transition of the feeding speed of the second feeding roller 9 is as indicated by 602 in FIG. 43B, and the feeding speed is accelerated to the image forming speed V1 between time t2 and time t3, Thereafter, the image forming speed V1 is maintained.

  FIG. 43 (c) shows a combination of the speed profile indicated by 601 in FIG. 43 (a) and the speed profile indicated by 602 in FIG. 43 (b).

  The time transition of the interval between the original P1 and the original P2 is as shown in FIG. 43 (d). When the document P1 and the document P2 are stopped, the sheet interval is L8. In this state, the conveyance by the wide belt 7 is started at time tl, and the sheet interval is gradually opened. As already described, at the time t2, the conveyance of the second feeding roller 9 is also started, and at the time t3, both speeds coincide with the image forming speed V1. Image reading starts at time t4. When the distance that the preceding document P1 moves between time t1 and time t3 is S1, and the distance that the subsequent document P2 moves between time t2 and time t3 is S2, the following relationship, that is,

S1-S2 = L6-L8
The time t2 is determined based on this. Actually, when the preceding document is conveyed by the wide belt 7 for a distance (L6-L8), the second feeding roller 9 is driven with a predetermined speed profile.

  Note that the speed V2 is not related to these, and is determined by the image forming speed V1 and the above-described L5 (distance between the reading position and the standby position).

When the image formation of the preceding document is completed, the trailing edge of the subsequent document is still nipped by the second transport roller 9. When the trailing edge of the subsequent document passes the nip of the second conveyance roller 9, the second conveyance roller 9 is stopped, and registration loop control of the subsequent document P3 is enabled. Even after the second conveying roller 9 is stopped, the preceding document P1 and the succeeding document P2 are transported by the wide belt 7 and stopped when the leading edge of the succeeding document P2 reaches the front of the reading position R2 (distance L5). . At this time, the trailing edge of the succeeding document P2 is located at a distance L8 from the nip of the second conveying roller 9.
[Operation in large-size single-sided document transport mode]
The operation in the large-size single-sided document conveyance mode is essentially not different from the operation in the half-size single-sided document conveyance mode, but the following points are different because the document sizes are different.

  That is, in the half-size single-sided document conveyance mode, the reading position is L2, that is, from the nip point of the second feeding roller 9.

L2 = L8 + Conveyed document size + L5
In the large size single-sided document conveyance mode, L3, that is,

L3 = L10 + Conveyed document size + L5
It is in a position separated by a distance. However, L10 is the distance from the trailing edge of the original to the nip point of the second feeding roller 9 when the conveyance by the wide belt 7 is temporarily stopped.

  When the trailing edge of the document P1 passes through the nip point of the first paper feed roller 5, the separation clutch 106 is turned on, and the state when the paper feed roller 5 starts feeding the subsequent document P2 is shown in FIG. Shown in a).

  Since L10> 0, the document is independently conveyed by the wide belt 7, and when the trailing edge of the document is stopped once it has advanced a predetermined distance after passing through the paper feed sensor 35, the trailing edge of the document is the second feeding roller. 9 nip points are passed. This state is shown in FIG.

  Also, the following points are different. That is, in the half-size single-sided document conveyance mode, the distance between the sheets is determined when the conveyance speed (image formation speed) of the preceding document P1 by the wide belt 7 and the conveyance speed of the second feeding roller 9 that conveys the document P2 coincide. The speed of the second feeding roller 9 is controlled so as to be L6. On the other hand, in the large-size single-sided document conveyance mode, the speed of the second feeding roller 9 is controlled so that the inter-paper distance is L11. The state after this speed control is shown in FIG.

Both the inter-paper distance L6 and the inter-paper distance L11 are distances from the leading edge of the original document to be ejected next to the currently ejected original document to the nip point of the manual registration roller 11 after being temporarily stopped after image reading. It is bigger. Specifically, the inter-paper distance L6 is larger than the distance from the leading edge of the subsequent original P2 that has been temporarily stopped after the image reading of the original P2 to the nip point of the manual registration roller 11, whereas the inter-paper distance. L11 is larger than the distance from the leading edge of the succeeding document P2 that has been temporarily stopped after reading the image of the document P1 to the nip point of the manual registration roller 11. FIG. 16B shows a state after the original image is read.
[Description of half-size double-sided document conveyance]
17 to 20 show the flow of the document in the duplex document conveyance mode. When the document transport mode is set to the double-sided document transport mode, the reverse feed flapper 22 and the reverse flapper 23 are positioned at the positions indicated by the solid lines in FIG. 3, and the transport path is the reverse feed path (h), ( F), (re). Accordingly, the document fed by the first feeding roller 16 and the second feeding roller 9 is guided to (re) through the reverse feeding paths (H) and (H). This is shown in FIG.

  When the trailing edge of the document P1 passes through the one-way flapper 24, the rollers 17 and 18 are reversed, and the rollers 17 and 18 cause the document P1 to reverse the reverse feeding paths (h), (f), and (re). And is guided to a conveyance path (d) on the platen 3 via a supply / discharge flapper 25 at a position indicated by a solid line in FIG. This is shown in FIG.

  When the trailing edge of the document P1 guided to the transport path (d) is detected by the reverse sensor 50 and transported a predetermined distance from the position where the trailing edge of the document P1 is detected, the wide belt 7 transports the document P1. The document P1 is stopped, and the document P1 is placed at the reading position R1 in the fixed reading mode with the second side facing down. This is shown in FIG. When the placement of the document P1 is completed, the path switching solenoid 107 is turned off, and the reverse feed flapper 22 and the feed / discharge flapper 25 are positioned at the positions indicated by the one-dot chain line in FIG.

  When the placement of the document P1 is completed, the second surface of the document P1 is scanned by the scanner. When the reading of the document P1 is completed, the wide belt 7 is reversed, and at the same time, the reverse flapper 23 is moved to the position indicated by the one-dot chain line in FIG. 3, and the document P1 is moved by the wide belt 7 through the supply / discharge flapper 25. It is conveyed to the supply / discharge path (e) and guided to the document reversing path (g) by the first reversing roller 17 and the second reversing roller 18. This state is shown in FIG. Then, when the leading edge of the document P1 is detected by the reverse sensor 50 and the document is conveyed by a predetermined distance from the position where the leading edge of the document is detected, the rotation of the wide belt 7 is temporarily stopped and the rotation of the wide belt 7 is normal. Can be switched. Control is performed so that the transport speeds of the second feeding roller 9 and the wide belt 7 coincide with each other when the front end of the inverted document P1 reaches the transport path (d) on the platen 3.

  When the trailing edge of the document P1 guided to the document reversing path (g) passes the nip point of the second feeding roller 9, the second feeding roller 9 is stopped and the subsequent document P2 is moved to the second feeding roller 9. Wait for it to arrive. The document P1 that has passed through the second feeding roller 9 is independently conveyed by the wide belt 7. When the document P1 conveyed by the wide belt 7 is conveyed by a predetermined distance after the trailing edge of the document P1 is detected by the paper feed sensor 35, the conveyance is stopped and the first position P1 is again returned to the reading position R1. Placed face down. Further, when the trailing edge of the document P1 is detected by the paper feed sensor 35, the document P2 is separated, and a known skew feeding is performed by the second feed roller 9.

  When the placement of the document P1 is completed, the first surface is scanned by the scanner. While the scanner scans the first surface of the document P1, the document P2 is reversed in the same manner as the reversal of the document P1, and waits with the vicinity of the front end of the document P2 nipped by the first reversing roller 17. To do. This is shown in FIG.

  When the scanning of the first surface of the preceding document P1 is completed, the first reversing roller 17 and the second reversing roller 18 are reversed, the wide belt 7 is rotated forward, and the succeeding document P2 is moved together with the preceding document P1 to the platen 3. Carried over. When the succeeding document P2 reaches the reading position R1, the rotation of the wide belt 7 is stopped, and the succeeding document P2 is placed at the reading position R1, and only a predetermined inter-paper distance (L12) from the succeeding document P2. The preceding document P1 is placed at a position on the platen 3 that is away. This situation is shown in FIG. When the placement of the succeeding document P2 at the reading position R1 is completed, the second surface of the succeeding document P2 is scanned by the scanner.

  When the scanning of the second surface of the succeeding document P2 is completed, the wide belt 7 is reversed, and the succeeding document P2 and the preceding document P1 are conveyed toward the reverse feeding path (e). Then, when the leading edge of the succeeding document P2 is detected by the reverse sensor 50 and the document P2 is conveyed by a predetermined distance from the position where the leading edge of the document is detected, the rotation of the wide belt 7 is temporarily stopped and the rotation of the wide belt 7 is performed. Is switched to normal rotation. At this time, since the trailing edge of the succeeding document P2 passes through the wide belt 7, only the preceding document P1 is conveyed on the platen 3 by the wide belt 7.

  On the other hand, the reversed succeeding document P2 is transported by the second feeding roller 9, and when the leading end of the succeeding document P2 reaches the transport path (d) on the platen 3, the transport of the second feeding roller 9 and the wide belt 7 is performed. Control is done so that the speeds are consistent. When the trailing edge of the succeeding document P2 passes the nip point of the second feeding roller 9, the second feeding roller 9 is stopped and waits for the next document P3 to arrive at the second feeding roller 9. The succeeding document P2 that has passed through the second feeding roller 9 is independently conveyed by the wide belt 7. The succeeding document P2 transported by the wide belt 7 is stopped when it is transported a predetermined distance after the trailing edge of the succeeding document P2 is detected by the paper feed sensor 35, and again returns to the reading position R1. Placed with the first side down. FIG. 20A shows the position of the preceding document P1 and the position of the document P3 when the succeeding document P2 is placed at the reading position R1. In a state where the subsequent document P2 is placed at the reading position R1, the document P3 stands by in a state where it is nipped by the first reversing roller 17, like the document P2 shown in FIG. The distance between the succeeding document P2 and the preceding document P1 placed at the reading position R1 is L13. The wide belt 7 may be driven and controlled so that the distance between the sheets is L12.

  When the placement of the subsequent document P2 at the reading position R1 is completed, the first surface of the subsequent document P2 is scanned by the scanner. When the scanning of the first surface of the succeeding document P2 is completed, the first reverse roller 17 and the second reverse roller 18 are reversed, the wide belt 7 is rotated forward, and the discharge roller 12 starts rotating. The first reverse roller 17 and the second reverse roller 18 transport the document P3 toward the transport path (d) on the platen 3, and the subsequent document P2 and the preceding document P1 discharge the transport path (d) on the platen 3. It is conveyed toward the roller 12. When the document P3 reaches the reading position R1, the wide belt 7 is stopped, and the document P3 is placed with the second side down.

  In the state where the document P3 is placed at the reading position R1, as shown in FIG. 20B, the trailing edge of the subsequent document P2 is immediately before the nip of the manual registration roller 11, so that the paper with the subsequent document P2 The preceding document P1 whose distance is L12 has a trailing edge that passes through the nip of the manual registration roller 11. The preceding original P1 that has passed through the nip of the manual registration roller 11 is independently conveyed by the paper discharge roller 12 and discharged to the paper discharge tray 10.

Thereafter, this cycle is repeated. When the scanning of the first surface of the final document Pn is completed, the final document Pn and the last previous document Pn-1 in the same state as shown in FIG. 19B are conveyed on the platen 3 by the wide belt 7 ( D) is continuously conveyed toward the paper discharge roller 12 and is discharged at once by the paper discharge roller 12.
[Description of conveyance of full-size duplex originals]
Compared with the operation at the time of half-size double-sided document conveyance, the operation at the time of full-size double-sided document conveyance is as follows. The point of passing through the nip is different.

  FIG. 21 to FIG. 24 show the flow of originals when a full-size double-sided original is conveyed. The preceding document P1 is reversed (see FIG. 21A), guided to the transport path (d) on the platen 3 with the second side down (see FIG. 21B), and read in the fixed reading mode. It is placed at the position R1 (see FIG. 22A), and the second surface of the preceding document P1 is scanned by the scanner. Then, the preceding document P1 for which the scanning of the first surface has been completed is reversed (see FIG. 22B) and guided to the conveyance path (d) on the platen with the first surface facing down, and is moved to the reading position R1. When the placement of the preceding document P1 is completed, the second surface of the preceding document P1 is scanned by the scanner.

  The separation operation of the succeeding document P2 is started before and after the detection of the trailing edge of the preceding document by the sheet feed sensor 35, and a known skew feeding is performed by the stopped second feeding roller 9, and the succeeding document P2 is As shown in FIG. 23 (a), they are led to the reverse feeding paths (H), (H), and (R).

  During the scanning of the first surface of the preceding document P1 by the scanner, the reversing operation of the succeeding document P2 is performed in the same manner as the preceding document P1, and the vicinity of the leading end of the succeeding document P2 when the reversing operation is completed is shown in FIG. As shown in FIG. 5B, the sheet is nipped by the first reverse roller 17 and is in a standby state. The distance between the preceding document P1 and the subsequent document P2 in the standby state at this time is controlled to be L14.

When the scanning of the first surface of the preceding document P1 is completed, the reverse rotation of the first reverse roller 17 and the second reverse roller 18 and the normal rotation of the wide belt 7 are started at the same time, as shown in FIG. The value of L14 is determined so that the trailing edge of the preceding document P1 passes through the nip point of the manual registration roller 11 when the succeeding document P2 is placed. Thereafter, the same operation as this is continued until the final document Pn.
[Document transport when manually feeding originals]
FIG. 25 and FIG. 26 show the flow of the original when manually feeding the original. When a document is set as shown in FIG. 25A and the document set is detected by the manual document detection sensor 60, the manual flapper 27 and the manual shutter 28 are switched to the positions shown by the solid lines in FIG. carried by the manual feed roller 13. The conveyed manual document is skewed by the manual registration roller 11 in a stopped state, and then guided to the conveyance path (d) on the platen 3 by the wide belt 7. When the leading edge of the manual document reaches the reading position R1 of the platen 3, the wide belt 7 is stopped, and then the manual document is scanned by the scanner 204 of the copying machine main body, and the manual flapper 27 and the manual shutter 28 are shown in FIG. Is returned to the position indicated by the alternate long and short dash line to enable the next document setting (see FIG. 25B). When the scanning by the scanner 204 is completed, the wide belt 7 is reversed, and the manual feed document is conveyed toward the paper discharge roller 12 by the wide belt 7.

When the paper discharge roller 12 rotates, the manual paper feed roller 13 also rotates, but the leading edge of the next manually fed document P2 is regulated by the manual shutter 28, the manual paper feed roller 13 slips, and the document P2 The process cannot proceed (see FIG. 26A). When the trailing edge of the document P1 is detected by the manual registration sensor 34, the manual registration roller 11 is stopped, and the manual flapper 27 and the manual shutter 28 are moved to positions indicated by solid lines in FIG. Then, the original P2 is conveyed toward the manual registration roller 11 by the manual paper feed roller 13, and as described above, after the skew feeding is completed, the original P2 is conveyed along the conveyance path (d) of the platen 3 and placed at the reading position R1. Is done.
[Description of control unit]
FIG. 27 will be described. 27, reference numerals 30 to 35, 39, and 50 denote the same parts as in FIG. 4, and reference numeral 40 denotes the same parts as in FIG.

  Reference numeral 201 denotes a CPU (central processing unit), and a drive unit for various loads and sensor signals from each sensor are connected to the input / output port. Reference numeral 201a denotes a random access memory (RAM), which is used as a work area. 201b is a ROM (read only memory) in which a control program is stored. A communication control unit 202 controls data communication with the copying machine main body 1.

  Reference numeral 203a denotes a controller, which receives a reference clock, an on / off signal, and the like serving as a reference for the motor rotation speed from the CPU 201, and drives and controls the separation motor 100 (DC brush motor) via the driver 203. A stepping motor driver 204 drives the conveyance motor 101 (stepping motor) based on the phase excitation signal and the motor current control signal from the CPU 201. A stepping motor driver 205 drives the belt motor 102 (stepping motor) at a constant current based on a phase excitation signal from the CPU 201 and a motor current control signal. Reference numeral 206 denotes a driver that drives the swing motor 103 (stepping motor) at a constant voltage. Reference numeral 207a denotes a controller for FG servo, which drives and controls the discharge motor 104 (DC brush motor) via the driver 207. As shown in FIG. 4, the encoder for detecting the rotation speed of the paper discharge motor 104 is composed of a clock plate 104a and a paper discharge clock sensor 104b.

  A driver 208 drives the shutter solenoid 105. A driver 209 drives the separation clutch 106. A driver 210 drives the path switching solenoid 107. Reference numeral 211 denotes a driver 211 that drives the reverse flapper solenoid 108. A driver 212 drives a paper discharge flapper solenoid. Each of the drivers 208 to 212 operates according to a signal connected to the input / output port of the CPU 201.

Separation sensor 30, skew detection sensor 31, mixed load detection sensor 32, reverse detection sensor 33, manual registration sensor 34, paper feed sensor 35, reverse sensor 50, manual document detection sensor 60, registration sensor 39, a document set sensor 40, a document trailing edge detection sensor 41, a final document detection sensor 43, a paper width detection sensor 44, a paper feed roller home sensor 45, and a swing position sensor 46 are provided as input ports of the CPU 201. It is connected and used to monitor the behavior of the document and the behavior of the movable load in the apparatus.
[Description of control program]
28 to 42 are flowcharts showing an example of a control program stored in the ROM 201b of FIG. When a copy key of an operation unit (not shown) of the copying machine main body 1 is pressed, control is started. It is determined whether a document set on the document tray 4 is detected by the document set detection sensor 40 (main 1). If a document set is detected, it is determined whether the copying mode from the copying machine body 1 is the single-sided document mode (main 2). If it is determined that the mode is not the single-sided mode, a series of copying processes are executed in the double-sided original mode (main 6), and then the control is terminated. On the other hand, if it is determined that the single-side mode is selected, it is determined whether or not the document trailing edge detection sensor 41 is turned off (main3). If it is determined that it is off, a series of copy processing is executed in a first flow reading mode to be described later (main 4), and then the control is terminated. On the other hand, if it is determined that it is not turned off, a series of copying processes are executed in a second flow reading mode to be described later (main 5), and then the control is terminated.

  In this embodiment, an example is described in which mode selection based on the document size is restricted only by the feed direction by turning on / off the document trailing edge detection sensor 41. As described above, the document is detected by the paper width detection sensor 44 below the document tray 4. Depending on the combination with the width detection means, mode selection may be regulated according to the document size.

On the other hand, if the document set is not detected by the document set detection sensor 40, it is determined whether or not the document set on the manual document tray is detected by the manual document set detection sensor. If not detected, a series of copying processes are executed in the manual feed mode described later (main 8), and then the control is terminated.
[First scanning mode]
FIG. 29 is a flowchart showing an example of a control program in the first flow reading mode (main4) of FIG. A pickup DOWN process, which will be described later, is performed to move the paper feed roller 5 on the document surface set on the document tray 4 (draftmd1), and a separation process (draftmd2), which will be described later, is performed to separate only one uppermost document. ) To perform a paper feed process (draftmd3). Next, a document flow reading process for reading a document image is started with the scanner 204 (FIG. 1) of the copying machine main body 1 fixed at a predetermined reading position (draftmd4), and the trailing edge of the document is detected by the separation sensor 30. (Draftmd5). When the trailing edge of the document is detected, it is determined whether the document set detection sensor 40 has detected the separation of the document bundle, that is, whether the document is the final document (draftmd6). If it is determined that the document is not the final document, a later-described sheet discharge process is started in order to discharge the document onto the sheet discharge tray 10 (draftmd7), and then the process returns to draftmd2. On the other hand, if it is determined that the document is the final document, a paper discharge process is performed (draftmd8), a pickup UP process described later is performed, the paper feed roller 5 is returned to the upper limit position (draftmd9), and then the control ends.

At this time, the scanner 204 shown in FIG. 1 is fixed at the position R2 in FIG. 11 when the original is a half size, and is fixed at the position R3 in FIG. 11 when the original is a large size. The position control of the scanner 204 may be performed by driving and controlling a stepping motor, or may be performed using a mechanical stopper configuration.
[Second scanning mode]
FIG. 30 is a flowchart showing an example of a control program in the second flow reading mode (main 5) of FIG. A pickup DOWN process, which will be described later, is performed in order to move the paper feed roller 5 onto the document surface set on the document tray 4 (draft2md1), and a separation process, which will be described later, is performed in order to separate only one uppermost document ( draft2md2) and paper feed processing (draft2md3). Next, the document flow scanning process is started (draft 2 md 4). Since the fixing position of the scanner 204 in FIG. 1 is in the vicinity of the sheet discharge unit, the sheet discharge process described later is started to discharge the document onto the sheet discharge tray 10. (Draft2md5), and waits until the trailing edge of the document is detected by the separation sensor 30 (draft2md6). Then, when the trailing edge of the document is detected, it is determined whether or not the document set detection sensor 40 has detected the separation of the document bundle, that is, whether or not the document is the final document (draft2md7). If it is not the final document, the process returns to draft 2 md 2, and if it is the final document, a pickup UP process described later is performed to return the paper feed roller 5 to the upper limit position (draft 2 md 8), and then the control ends. At this time, the scanner 204 is fixed at the reading position R3 shown in FIG.
[Duplex mode]
FIG. 31 is a flowchart showing an example of a control program in the double-sided document mode (main 6) of FIG. A pickup DOWN process, which will be described later, is performed in order to move the paper feed roller 5 onto the document surface set on the document tray 4 (dub1emd1), and a separation process, which will be described later, is performed to separate only one uppermost document ( doub1emd2). Next, a pre-inversion process (dub 1 emd 3), which will be described later, is performed to invert the separated document and place it on the reading position R 1 on the platen 3 so that the second side of the document is turned down. When the second surface is placed at the reading position R1 on the platen 3, the optical system moving document reading process is performed while moving the scanner 204 (dub1emd4).

  When the reading of the original on the second side is completed, the reversing process is performed again to reverse the front and back surfaces (dub1emd5). When the reversed original is placed at the reading position R1 with the first side down, An optical system moving document reading process is performed on one surface (dub1emd6).

Determining between a document set Gu Broken document bundle is detected by the detection sensor 40 Taka whether, I sand, whether the original is the last original is reading processing of the first surface of the original ( doub1emd7). If it is not the final document, a later-described sheet discharge process is started to discharge the document to the discharge tray 10 (dub1emd8), and the process returns to doub1emd2. On the other hand, if the document is the final document, a paper discharge process is performed (dub1emd9), a pickup UP process described later is performed to return the paper feed roller 5 to the upper limit position (dub1emd10), and the control is terminated.
[Manual feed mode]
FIG. 42 is a flowchart showing an example of a control program in the manual feed mode (main 8) of FIG. A manual paper feed process is performed on the document set in the manual paper feed unit (manual1md1), and when the manual document is placed at the reading position R1, an optical system moving document reading process is performed on the placed document. Perform (manualmd2). When the reading process is completed, the paper discharge process is started to discharge the original to the paper discharge tray 10 (manual 1 md 3), and waits until the manual registration sensor 34 detects the rear end of the original (manual 1 md 4). When the trailing edge of the original is detected, the manual original detection sensor 60 detects whether or not the next original exists in the manual paper feed unit. If there is an original, the process returns to manual1md5. If there is no original, Then, the manual paper discharge process is performed, and then the control is terminated.
[Pickup DOWN treatment]
FIG. 32 is a flowchart showing an example of the pickup DOWN processing procedure described above. The swing motor 103 is driven (pickupdwn1) to lower the paper feed roller 5 from the position where the paper feed roller home sensor 45 is on (FIG. 5) onto the original bundle P placed on the original tray. ), Elevating arm 51, swing arm 1, and swing arm 2 are lowered. Next, it waits until the paper feed roller home sensor 45 is turned off (pickupdwn2). When the paper feed roller home sensor 45 is turned off, after confirming that the paper feed roller has been lowered, the first swing position sensor 46 and Wait until the second swing position sensor 47 is turned on (pickupdwn3). Then, when the first swing position sensor 46 and the second swing position sensor 47 are turned on and it is detected that the paper feed roller 5 has fallen on the paper surface, the drive of the swing motor 103 is stopped (pickupdwn 4).
[Pickup UP processing]
FIG. 33 is a flowchart showing an example of the above-described pickup UP processing procedure. In order to raise the paper feed roller 5 to the position shown in FIG. 5, the swing motor 103 is driven (pickup 1), and then waits until the paper feed roller home sensor 45 is turned on (pickup 2). When it is detected that the paper feed roller home sensor 45 is turned on and reaches the upper limit position, the driving of the swing motor 103 is stopped (pickup 3). At this time, the rotation direction of the swing motor 103 is opposite to that during the pickup DOWN process.
[Separation process]
FIG. 34 is a flowchart showing an example of the above-described separation processing procedure. The separation clutch 106 and the separation motor 100 are turned on (sep1) to rotate the paper feed roller 5 that has been dropped onto the document bundle P, and the separation belt 6, the separation conveyance roller 8, and the first feeding roller 16. , And the sheet feeding roller 5 separates only one uppermost document in the document bundle P, and the separated document is guided to the transport path (A) by the separation belt 6 and the separation transport roller 8. When the separation sensor 30 is turned on and the leading edge of the document is detected (step 2), speed control of the separation motor 100 described later is performed (step 3). When the paper feed sensor 35 is turned on and the leading edge of the document is detected (step 4), a separation loop counter for counting clock signals input from the separation clock is started (step 5), and the set count is counted. (Spa6). When the counting is completed, the separation motor 100 is turned off (step 7), and the leading edge of the document is abutted against the nip portion of the second feeding roller 9 by the first feeding roller 16 to form a predetermined amount of loop. In the state in which the document is formed, the conveyance of the document is stopped, and the skew generated during the separation is corrected.
[Paper Handling]
FIG. 35 is a flowchart showing an example of the above-described paper feed processing procedure. In order to feed the separated document to the transport path (c), the path switching solenoid 107 is turned on, the reverse feed flapper 22 is switched to the position indicated by the one-dot chain line in FIG. 4 (ent1), the separation motor 100, The conveyance motor 101 and the belt motor 102 are turned on (ent2), and the first feeding roller 16, the second feeding roller 9, and the wide belt 7 are driven. The speed control of the separation motor 100 at this time will be described in detail with reference to FIG. Further, a size check counter for counting clock signals input from the inverted clock is started (ent3). When the registration sensor 39 leading edge of the document is detected, i.e., when the original is conveyed to the conveying path (c) it is confirmed (ENT4), until the trailing edge of the document is detected by the separation sensor 30 stand by.

  When the trailing edge of the document is detected by the separation sensor 30 (ent5), a separation activation counter for counting by a clock signal input from the separation clock is started (ent6) until the count by the separation activation counter is completed. ,stand by. When the counting for the distance from the first feeding roller 16 to the separation sensor 30 is completed (ent7), that is, when the trailing edge of the document passes through the first feeding roller 16, the separation motor 100 is rotated at a high speed. (Ent8). Thereafter, the process waits until the trailing edge of the document is detected by the paper feed sensor 35 (ent9).

When the trailing edge of the document is detected by the paper feed sensor 35, the size check counter is stopped (ent10), and a size check process (see FIG. 40) described later is performed based on the data of the size check counter (ent11). ). Next, in order to stop the original at a predetermined position on the platen 3, a registration counter for counting the belt excitation clock is started (ent 12), and is counted for a distance L 4 from the paper feed sensor 35 to the second feed roller 9. It waits until it does (ent13). When the counting for the distance L4 is completed, the transport motor 101 is turned off (ent14), and the process waits until the counting by the registration counter is completed. When the counting by the registration counter is completed (ent15), the belt motor 102 is turned off (ent16), and the path switching solenoid 107 is turned off (ent17).
[Pre-inversion processing]
FIG. 36 is a flowchart showing an example of the above-described pre-inversion processing procedure. The path switching solenoid 107 is off, and the reverse paper feed flapper 22 is in the position indicated by the solid line in FIG. In this state, the separation motor 100 and the conveyance motor 101 are turned on (pretrn1), and the first feeding roller 16, the second feeding roller 9, the first reverse roller 17, and the second reverse roller 18 are driven. Then, the original document nipped by the first feeding roller 16 is conveyed to the conveyance path (H). Also, a size check counter that counts clock signals input from the inverted clock is started (pretrn2). Next, the process waits until the registration sensor 39 detects the leading edge of the document.

When the registration sensor 39 leading edge of the document is detected, i.e., when the original is conveyed to the conveying path (h) is confirmed (Pretrn3), until the trailing edge of the document is detected by the separation sensor 30 Wait (pretrn4). When the separation sensor 30 detects the trailing edge of the document, a separation off counter for counting a clock signal input from the separation clock is started (pretrn 5), and the first feed roller 16 to the separation sensor 30 are started. Wait until the count for the distance is completed (pretrn6). When the counting by the separation off counter is finished, that is, when the trailing edge of the original passes through the first feeding roller 16, the separation motor 100 is turned off to stop the driving of the first feeding roller 16 (pretrn7), and the paper feed. It waits until the trailing edge of the original is detected by the sensor 35 (pretrn 8).

  When the trailing edge of the document is detected by the paper feed sensor 35, the size check counter is stopped (pretrn 9), and a size check process (see FIG. 40) described later is performed based on the data of the size check counter (pretrn 10). ). Next, the process waits until the registration sensor 39 detects the trailing edge of the document (pretrn 11). When the registration sensor 39 detects the trailing edge of the document, a pre-inversion counter is started to count the inversion excitation clock so that the trailing edge of the document stops at a predetermined position after passing through the conveyance path (h) (pretrn12). . At this time, the reverse flapper 23 is in a position indicated by a solid line in FIG. 4 and is urged so that the document is conveyed to the conveyance path (re).

When the counting by the pre-reverse counter is completed (pretrn 13), the transport motor 101 is turned off for a predetermined time and then turned on to reverse the belt motor 102 and the belt motor 102 is turned on (pretrn 15). Wait until the leading edge of the document is detected (pretrn 16). When the leading edge of the original is detected by the reverse sensor 36, i.e., when the original is conveyed to the conveying path (e) is confirmed, to wait by the reverse sensor 36 to the trailing edge of a document is detected ( pretrn 17). When the reversing sensor 36 detects the trailing edge of the document, the conveying motor 101 is turned off (pretrn 18), and a pre-feed counter for counting the belt excitation clock is used to stop the document at a predetermined position on the platen. Start (pretrn 19), and wait until the pre-feed counter finishes counting (pretrn 20). When the counting by the pre-feed counter is completed, the belt motor 102 is turned off (pretrn 21).
[Reversal processing]
FIG. 37 is a flowchart showing an example of the above reversal processing procedure. The reverse flapper solenoid 108 is turned on, the reverse flapper 23 is switched to the position indicated by the solid line in FIG. 4, the path switching flapper solenoid 107 is turned on, and the reverse feed flapper 22 and the supply / discharge flapper 25 are respectively shown by a one-dot chain line in FIG. (Trn1). Further, in order to transport the original on the platen 3 to the transport path (e), the belt motor 102 and the transport motor 101 are turned on (trn2), the wide belt 7, the second feeding roller 9, and the first reverse roller. 17 and the second reversing roller 18 are driven, and after that, the reversing sensor 36 waits until the leading edge of the document is detected (trn3).

  When the leading edge of the document is detected by the reversing sensor 36, that is, when the leading edge of the document reaches a predetermined position in the transport path (G) through the transport path (f), the belt motor 102 is stopped and reversed. An inversion counter for counting the belt excitation clock is started (trn4) and waits until the counting by the inversion counter is completed (trn5). When the counting by the reverse counter is completed, the belt motor 102 is turned off for a predetermined time (trn6), and then the belt motor 102 is reversely rotated (trn7). Next, the process waits until the paper feed sensor 35 detects the leading edge of the document. While the belt motor 102 is rotating in the reverse direction, the first reverse roller 17, the second reverse roller 18, and the second feed roller 9 are driven by the conveyance motor 101, and the original is conveyed in the conveyance path (F), (G). Will be transported.

  When the leading edge of the document is detected by the paper feed sensor 35 (trn8), that is, when it is confirmed that the document is transported through the transport path (g), the trailing edge of the document is detected by the registration sensor 39. (Trn9). When the registration sensor 39 detects the trailing edge of the document, the conveyance motor 101 is turned off (trn10), and a reverse feed counter for counting the belt excitation clock is set to stop the document at a predetermined position on the platen. Start (trn11) and wait until the count is completed (trn12).

  When the counting by the reversing paper feed counter is completed, the belt motor 102 is turned off (trn13), the reversing flapper solenoid 108 is turned off, the reversing flapper 23 is returned to the position shown by the solid line in FIG. Is turned off, and the reverse feed flapper 22 and the feed / discharge flapper 25 are returned to the positions indicated by the solid lines in FIG. 4 (trn14).

At trn7, the direction in which the original is pulled by the first reverse roller 17 and the wide belt 7 is opposite to each other, but the nip force of the first reverse roller 17 is stronger than the nip force of the wide belt 7. Is conveyed following the first reverse roller 17. However, in the case of a document that is long in the feeding direction, it is greatly affected by the nip force between the pressing roller inside the wide belt 7 and the platen 3 and does not follow the first reverse roller 17, so the belt motor 102 is stopped, The timing of reverse rotation, that is, the value of the reverse counter is controlled so as to vary depending on the length of the document in the feed direction.
[Discharge Processing]
FIG. 38 is a flowchart showing an example of the paper discharge processing procedure described above. The paper discharge flapper solenoid 109 is off, and the paper discharge flapper 26 is urged to a position where the tip of the flapper is lower than the platen 3 as shown by a one-dot chain line in FIG. In this state, both the belt motor 102 and the paper discharge motor 104 are turned on (ejct1) to convey the original on the platen 3 to the conveyance paths (d) and (n), and the wide belt 7 and the manual paper feed The roller 13 and the paper discharge roller 12 are driven. Next, the process waits until the leading edge of the original is detected by the manual registration sensor 60 (ejct2). When the leading edge of the document is detected by the manual registration sensor 60, that is, when it is confirmed that the document is transported through the transport path (n), the process waits until the trailing edge of the document is detected by the manual registration sensor 60. (Ejct3). When the manual registration sensor 34 detects the trailing edge of the document, the belt motor 102 is turned off (ejct4), and a paper discharge counter for counting the clock signal input from the paper discharge clock is started (ejct5). Wait until the count by the paper discharge counter is completed (ejct6). When the counting by the paper discharge counter is completed, the paper discharge motor 104 is turned off (ejct7). The original passes through the transport path (n), passes through the paper discharge roller 12, and is discharged onto the paper discharge tray 10.
[Manual Feeding]
FIG. 41 is a flowchart showing an example of the paper discharge processing procedure described above. The manual flapper 26 is abutted against the leading edge of the document set in the manual paper feeder. The paper discharge flapper solenoid 109 is off, and the paper discharge flapper 26 and the manual shutter 28 are urged to a position where the front end of the paper discharge flapper 26 is lower than the platen, as shown by the solid line in FIG. In this state, the paper discharge flapper 109 is turned on, the manual shutter 28 and the paper discharge flapper 26 are switched to the positions indicated by the alternate long and short dash line in FIG. 4 (ment 1), the paper discharge motor 104 is turned on (ment 2), and manual feed is performed. The paper feed roller 13 is rotated to transport the original in the transport path (L). Next, the process waits until the manual registration sensor 34 is turned on.

  When the leading edge of the document is detected by the manual registration sensor 34 (ment 3), a manual loop counter for counting the clock signal input from the paper discharge clock is started (ment 4) and waits until the counting is finished (ment 4). ment5). When the counting by the manual feed loop counter is completed, the paper discharge motor 104 is turned off for a predetermined time (ment 6). In order to correct the skew of the document generated during the conveyance by the manual feed roller 13, the leading end of the document is abutted against the nip portion of the manual registration roller 11 and stops in a state where a predetermined amount of loop is formed. After the paper discharge motor 104 is turned off, the paper discharge motor 104 and the belt motor 102 are turned on (ment 7) in order to transport the original to the transport paths (l) and (d), the manual paper feed roller 13, the manual registration The roller 11 and the wide belt 7 are driven. Next, a size check counter for counting clock signals input from the belt clock is started (ment 8). Further, in order to stop the original at a predetermined position on the platen 3, a belt registration counter for counting the belt excitation clock is started (ment 9), and the process waits until the manual registration sensor 34 detects the rear end of the original (ment 10). ).

When the manual registration sensor 34 is turned off and the trailing edge of the document is detected, the size check counter stops counting and a size check process (see FIG. 41) described later is performed based on the count data (ment11). . Next, since the trailing edge of the original has passed through the manual feed roller 13, the paper discharge motor 104 is turned off (ment 12), and the process waits until the count by the manual registration counter is completed (ment 13). When the count by the manual registration counter is completed, the belt motor 102 is turned off (ment 14), and the paper discharge flapper solenoid 109 is turned off (ment 15).
[Original Scanning Processing]
FIG. 39 is a flowchart showing an example of the above-described document feed reading processing procedure. In order to read an image of a document with the optical system of the copying machine main body 1 fixed, the belt motor 102 is turned on (move 1), and the wide belt 7 is driven. Next, in order to turn on the image destination signal when the leading edge of the document reaches a predetermined position, an image destination on-counter for counting the belt excitation clock is started (move 2) until the counting by the image destination on-counter ends. Wait (move 3). At this time, the belt motor is controlled at a constant speed by outputting an excitation clock signal based on the flow reading speed data (V) from the copying machine main body 1.

  When the counting by the image destination on counter is completed (move 3), the image destination signal is turned on (move 4), and the image destination off timer is started (move 5). When receiving the turned-on image destination signal, the copying machine main body 1 calculates the time until the leading end of the document reaches the optical system fixing position during the flow reading, and performs actual image reading. When a predetermined time set in the image destination off timer elapses (move 6), the image destination signal is turned off from on (move 7), and the belt motor 102 is turned off when the trailing edge of the document passes the reading position. (Move 8).

The flow reading speed data (V) may be equal to or different from the reading speed (V1) when the optical system is moved. In particular, when V> V1, the original image is read in a shorter time than the normal optical system moving reading, so that the copying speed is improved by using the original feeding device of the present invention.
[Size check processing]
FIG. 40 is a flowchart showing an example of the size check processing procedure described above. In this size check process, first, the true document size (feed direction length) is corrected by adding the distance from the nip position of the second feed roller 9 to the paper feed sensor 35 to the size check counter data. Document length data is calculated (size 1). In this process, the document is conveyed by the second feeding roller 35 and the wide belt 7, and the feeding amount and the count value based on the belt excitation clock surely match.

  When it is determined that the document length data is not less than A3 (size2), the document size is determined as A3 (size14).

  If the document length data is less than A3 but not less than B4 (size 3), the document size is determined to be B4 (size 13).

  When the document length data is less than B4 but not less than A4R (size4), the document size is determined as A4R (size12).

  If the document length data is less than A4R but not less than B5R (size5), the document size is determined to be B5R (size11).

  If the document length data is less than B5R but not less than A4 (size6), the document size is determined as A4 (size10).

  When the document length data is less than A4 but not less than B5 (size 7), the document size is determined to be B5 (size 9).

If the document length data is less than B5 (size 7), the document size is determined as A5 (size 8).
<Second Embodiment>
FIG. 44 shows a second embodiment of the present invention. 44, 30, 35, 203 and 203a indicate the same parts as in FIG. 27, and 100 and 100b indicate the same parts as in FIG. Reference numeral 601 denotes a control unit that drives and controls the separation motor by the speed control loop 2020 and the movement amount control loop 2021.

  The control unit 601 will be described. A timing / gain control unit 2014 designates a separation operation timing in response to detection by the separation sensor 30 in a document feeding sequence, determines a gain of a speed control period loop in each separation operation, and each counter. Is performed, and separation control is performed. Reference numeral 2013 denotes a separation / conveyance speed setting unit, which sets conditions for each part according to the separation operation, the conveyance operation, the synchronization operation with the second feeding roller 9, and the image reading speed. Reference numeral 2004 denotes a reference clock generation unit that generates a reference clock 2005 for controlling the speed of the separation motor 100. This clock is output in relation to the excitation clock frequency of the stepping motor 101 that drives the first feeding roller 9. An up / down counter 2006 outputs a difference between the reference clock from the reference clock generation unit 2004 and the separated clock 2022 from the separated clock sensor 100b. A pulse counter loop gain setting unit (Gpcd) 2007 sets the loop gain of the movement amount control loop 2021 according to the difference from the up / down counter 2006. Reference numeral 2011 denotes an initial duty setting unit that sets a duty corresponding to the initial rotation control voltage of the separation motor 100 in accordance with the conditions set by the separation conveyance speed setting unit 2013. Reference numeral 2018 denotes an arithmetic unit that adds the loop gain set by the pulse counter loop gain setting unit 2007 and the duty set by the initial duty setting unit 2011.

  Reference numeral 2002 denotes an A / D converter that converts an analog signal from the controller 20a into a digital signal. Reference numeral 2016 denotes a calculation unit that calculates the difference between the output from the A / D converter 2002 and a predetermined reference value (128 in this case). Reference numeral 2003 denotes a PLL loop gain setting unit (Gpll), which sets the loop gain of the speed control loop 2020 based on the difference obtained by the calculation of the calculation unit 2016. A calculation unit 2019 adds the addition result of the calculation unit 2018 and the output of the PLL loop gain setting unit 2003.

  Reference numeral 2001 denotes a pulse width modulation control unit (PWM) that controls the energization rate to the separation motor 100 via the driver 203 according to the calculation result from the calculation unit 2019.

  An AND gate 2008 outputs a reference clock 2005 while the separation sensor 30 is off. Reference numeral 2009 denotes a counter that counts clocks output from the AND gate 2008. A paper size detection unit 2015 detects the paper size based on a sensor on the tray, the number of conveyance clocks during document conveyance, and the like. A paper interval setting unit 2010 calculates an appropriate paper interval based on the paper size detected by the paper size detection unit 2015. A calculation unit 2017 calculates a difference between the sheet interval set by the sheet interval setting unit 2010 and the count value from the counter 2009, that is, preset data of the up / down counter 2006.

2012 is a counter that counts the separated clock 2022 from the separated clock sensor 100b and outputs the count value to the timing / gain control unit 2014. By the reset signal from the timing / gain control unit 2014, the up / down counter It is reset at the same time as 2006 and the counter 2009.
[Description of Speed Control Loop 2020]
The speed control loop 2020 includes a separation clock sensor 100b, a controller 203a, an A / D converter 2002, a calculation unit 2016, a PLL loop gain setting unit 2003, a calculation unit 2019, a pulse width modulation control unit 2001, and a driver. 203 and the separation motor 100, and a well-known PLL speed control is performed on the separation motor 100 to control the reference clock 2005 and the separation clock 2022 from the encoder so as to be in frequency / phase synchronization. . As described above, the loop gain of the speed control loop 2020 can be set by the PLL loop gain setting unit 2003. The loop gain can be changed depending on the mode. In some cases, the speed control loop 2020 is disabled. Can be. This speed control loop 2020 is mainly effective when the original is nipped between the first feeding roller 16 and the second feeding roller 9 and conveyed. As a result, the document can be conveyed synchronously.
[Description of Movement Amount Control Loop 2021]
The movement amount control loop 2021 includes a separation clock sensor 100b, an up / down counter 2006, a pulse counter loop gain setting unit 2007, a calculation unit 2018, a calculation unit 2019, a pulse width modulation control unit 2001, a driver 203, The separation motor 100 is configured.

The movement amount control loop 2021 is a control loop for controlling the movement amount of the subsequent document. The distance between the subsequent document and the preceding document is set so that the distance between the preceding document and the subsequent document becomes a value set by the paper interval setting unit 2010. There is control. That is, when the leading edge of the succeeding document is detected by the separation sensor 30, the difference between the count value of the counter 2009 and the output of the sheet interval setting unit 2010 is calculated by the calculation unit 2017, and the difference is input to the up / down counter 2006. When the presetting is completed and the difference presetting is completed, the up / down counter 2006 starts counting.

  A reference clock 2005 corresponding to the amount of movement of the preceding document is input to the upcount input of the up / down counter 2006, and a separation clock 2022 corresponding to the amount of movement of the subsequent document is input to the downcount input. Since the movement amount control is performed so that the output of the up / down counter 2006 becomes zero (the difference in movement amount is zero), fluctuations in the sheet interval that occur during document conveyance are collectively corrected. When the value of the up / down counter 2006 falls within the predetermined value, the position correction of the succeeding document is completed, and the interval between the preceding document and the succeeding document (distance between sheets) is a value set by the sheet spacing setting unit 2010. become.

  Thereafter, the amount of movement of the subsequent original is controlled by the first paper feed roller 16 so that the inter-paper distance is constant. As a result, the rotation speed of the first paper feed roller 16 is controlled to be the same as the rotation speed of the second paper feed roller 9, and the subsequent document and the preceding document move at the same speed. However, because of the control method, the speed between the two originals cannot be synchronized with high accuracy, and this movement amount control loop 2021 is effective until the leading edge of the subsequent original reaches the second feeding roller.

Since the loop gain of the position control can be changed by the pulse counter loop gain setting unit 2007, the loop gain can be increased or decreased depending on the operation mode, and in some cases, this speed control loop can be disabled. . The configuration of the control unit 601 has been described with reference to a hardware block diagram for the sake of convenience, but in practice it can be realized by peripheral functions of the CPU 201 and a control algorithm.
[Separate motor control flow]
FIG. 45 is a flowchart showing the speed control switching state of the separation motor 100.

  This flowchart shows a control state in which the original is continuously separated and fed, and starts from the point where the uppermost original on the tray is fed as shown in FIG.

  First, after waiting for the paper feed process to start (entch 1), the PLL speed control loop 2020 is enabled, and a reference clock for PLL control is output, and a value corresponding to the initial voltage applied to the separation motor 100 Is set in the PWM register (entcht2). The separation motor 100 is turned on (entch 3), and the output voltage from the phase / frequency comparator is A / D converted periodically (entch 4). The A / D converted value is offset by a predetermined amount (entcht5), multiplied by a certain coefficient (Gpll), and added to the PWM value corresponding to the initial voltage (entcnt6), and a new applied voltage is separated by the separation motor 100. The rotation speed changes in addition to.

  Next, it waits for the trailing edge of the preceding document to pass through the separation sensor 30 (entch7). While the preceding document is on the separation sensor 30, the process returns to the encht4, and the updating of the PWM value is repeated to control the separation motor at a constant speed.

  When the trailing edge of the preceding document passes through the separation sensor 30, the movement amount control process is started, and the paper interval counter register is reset and started. As a result, the reference clock is input to the document interval counter and counted up. This count value is a value corresponding to the distance between the separation sensor 30 and the trailing edge of the preceding document (sepnt1). Next, the paper feed roller 5 is lowered and pre-separation processing such as connection of the separation clutch 106 is performed (sepnt 2).

  In this state, the first feeding roller 16 and the second feeding roller 8 cooperate to convey the preceding document, and the PLL speed control loop 2020 is effective.

  Next, initial setting for the movement amount control mode is performed (sepnt3). That is, resetting the up / down counter register, setting a paper interval control value in the paper interval register, outputting a reference clock corresponding to the preceding document conveyance amount, and a value corresponding to an applied voltage for rotating the separation motor 100 at high speed Is set in the PWM register. Next, the speed control mode of the separation motor 100 is switched to the movement amount control loop 2021. By this switching, the PWM motor-modulated initial voltage for high-speed rotation is applied to the separation motor 100, and the separation motor 100 is accelerated (sepnt 4).

When the leading edge of the subsequent document is detected by a separation sensor 30 (sepcnt5), turns off the separating clutch 106 (sepc n t6). Clock input to the document interval counter is prohibited by the AND circuit 2008, and the value of the counter maintains a value corresponding to the interval between the preceding document and the subsequent document. Further, the difference between the value of the document interval counter and the paper interval control value of the paper interval register is calculated (sepcnt7), and the calculation result (target paper interval) is preset in the up / down counter (sepcnt8). The up / down counter counts up using the reference clock and counts down using the separated clock 100b (sepcnt9). The value of the up / down counter is read at a constant timing, multiplied by a certain coefficient (multiplied by Gpcd), and added to the PWM value corresponding to the initial voltage (sepcnt10). The applied voltage is applied to change the rotation speed.

  When it is detected that the leading edge of the succeeding document has been applied to the paper feed sensor 35 (stepcnt11), the movement amount control is ended (stepcnt12), and the skew correction of the document described in the separation process flowchart of FIG. 34 is performed. If the paper feed sensor 35 does not detect the subsequent document, the process returns to sepcnt 10 and continues to update the PWM value.

  By performing such control, when the document is transported only by the separation unit (the paper feed roller 5, the separation transport roller 8, and the first feed roller 16), the rotational accuracy of the first transport roller is sacrificed. When the document is fed simultaneously by the first feeding roller 16 and the second feeding roller 9, the first feeding roller 16 is rotated. Since speed control is performed with priority given to accuracy, it is possible to prevent the documents from being pulled by both rollers.

1 is a cross-sectional view showing a structure of a copying machine. FIG. 2 is a cross-sectional view illustrating a structure of an image forming unit 300 in FIG. 1. It is sectional drawing which shows the path | pass of ADF2. It is sectional drawing which shows the drive system of ADF2. FIG. 10 is an explanatory diagram (No. 1) for explaining the operation of the separation unit of the ADF 2, which is an AA arrow view of FIG. 9. FIG. 10 is an explanatory diagram (No. 2) for explaining the operation of the separation unit of the ADF 2, which is an AA arrow view of FIG. 9. It is AA arrow directional view of FIG. 9, Comprising: It is explanatory drawing (the 3) for demonstrating operation | movement of the isolation | separation part of ADF2. FIG. 10 is an explanatory diagram (No. 4) for explaining the operation of the separation unit of the ADF 2, which is an AA arrow view of FIG. 9. It is a top view which shows the structure of ADF2. FIG. 4 is a diagram illustrating an arrangement of a sheet feeding roller 5 and a separation conveying roller 8. FIG. 6 is an explanatory diagram for explaining a document reading position. It is explanatory drawing explaining a primary contract reading position. FIG. 6 is a diagram (part 1) illustrating a document flow when a half-size single-sided document is conveyed. FIG. 6 is a diagram (part 2) illustrating the flow of a document when a half-size single-sided document is conveyed. FIG. 6 is a diagram (part 1) illustrating a flow of a document when a large-size single-sided document is conveyed. FIG. 10 is a diagram (part 2) illustrating a flow of a document when a large-size single-sided document is conveyed. FIG. 6 is a diagram (part 1) illustrating a flow of a document when a half-size duplex document is conveyed. FIG. 10 is a diagram (part 2) illustrating a flow of a document when a half-size duplex document is conveyed. FIG. 10 is a diagram (No. 3) illustrating the flow of a document when a half-size duplex document is conveyed. FIG. 10 is a diagram (part 4) illustrating the flow of a document when a half-size duplex document is conveyed. FIG. 5 is a diagram (part 1) illustrating a document flow when a full-size duplex document is conveyed. FIG. 6 is a diagram (part 2) illustrating the flow of a document when a full-size duplex document is conveyed. FIG. 10 is a diagram (part 3) illustrating the flow of a document when a full-size duplex document is conveyed. FIG. 10 is a diagram (part 4) illustrating the flow of a document when a full-size duplex document is conveyed. FIG. 6 is a diagram (part 1) illustrating a flow of a document during manual document feeding. FIG. 10 is a diagram (part 2) illustrating a flow of a document when a manual document is conveyed. It is a block diagram which shows the 1st Embodiment of this invention. It is a flowchart which shows an example of the control program stored in ROM201b of FIG. It is a flowchart which shows an example of the control program in the 1st flow reading mode (main4) of FIG. It is a flowchart which shows an example of the control program in the 2nd flow reading mode (main5) of FIG. FIG. 29 is a flowchart showing an example of a control program in the double-sided document mode (main 6) of FIG. 28. FIG. It is a flowchart which shows an example of a pickup DOWN process sequence. It is a flowchart which shows an example of a pick-up UP process sequence. It is a flowchart which shows an example of a separation process procedure. 6 is a flowchart illustrating an example of a paper feed processing procedure. It is a flowchart which shows an example of a pre inversion process sequence. It is a flowchart which shows an example of the inversion processing procedure. 6 is a flowchart illustrating an example of a paper discharge processing procedure. 6 is a flowchart illustrating an example of a document flow scanning process procedure. It is a flowchart which shows an example of a size check process sequence. 6 is a flowchart illustrating an example of a paper discharge processing procedure. FIG. 29 is a flowchart showing an example of a control program in the manual feed mode (main 8) of FIG. 28. FIG. FIG. 6 is an explanatory diagram for explaining the conveyance speed control of the wide belt and the feeding speed control of the second feeding roller. It is a block diagram which shows the 2nd Embodiment of this invention. It is a block diagram which shows the 3rd Embodiment of this invention. It is explanatory drawing explaining the document feeding control in the conventional sink reading.

Explanation of symbols

1 Copier body 2 ADF
3 Platen 4 Document Tray 5 Paper Feeding Roller 6 Separation Belt 7 Wide Belt 8 Separation Transport Roller 9 Second Feeding Roller 10 Paper Discharge Tray 11 Manual Registration Roller 12 Paper Discharge Roller 13 Manual Paper Feed Roller 14 Manual Document Feed Tray 16 First Feed Feed roller 17 First reverse roller 18 Second reverse roller 21 Stopper 22 Reverse feed flapper 23 Reverse flapper 24 One-way flapper 25 Feed flapper 26 Discharge flapper 27 Manual flapper 28 Manual shutter 30 Separation sensor 200 Leader 202 Lamp 203 First 1 mirror 204 scanner 205 second mirror 206 third mirror 207 lens 208 image sensor 300 printer unit

Claims (4)

A document feeding device that feeds a document to a reading position of an image reading device, for separating a plurality of stacked documents one by one, and for feeding a document separated by the separation unit A first feeding unit, a second feeding unit provided on the downstream side of the first feeding unit, and a plurality of documents provided on the downstream side of the second feeding unit to the reading position. In a document feeder having transport means ,
Before the leading edge of the succeeding document fed by the first feeding means enters the second feeding means, the distance between the preceding document and the preceding document preceding the succeeding document is previously set. Control means for controlling the rotational speed of the first feeding means according to the difference from the determined inter-paper distance ;
The control means further controls the leading document after the leading edge of the succeeding document is brought into contact with the second feeding means so that the distance between the preceding document and the succeeding document becomes a first distance. The rotational speed of the second feeding unit is controlled so that the distance from the subsequent document becomes a second distance longer than the first distance, and the conveying unit keeps the second distance. An original feeding apparatus that conveys the preceding original and the subsequent original . In claim 1, before Symbol control means,
Clock generating means for generating a number of clocks corresponding to the rotational speed of a first motor for driving the separating means and the first feeding means;
A reference clock generating means for controlling the rotation speed of a second motor for driving the second feeding means;
The number of clocks generated by the reference clock generation unit between the time when the trailing edge of the preceding document is detected at a predetermined position before the first feeding unit and the time when the leading edge of the subsequent document is detected; Difference calculating means for calculating a difference from a clock number corresponding to a predetermined interval between papers according to a document size to be performed;
The difference calculated by said difference calculating means is preset, to the preset simultaneously, with counts up the reference clock generated by the reference clock generating means, for counting down the number of pulses generated by the clock generating means With an up / down counter,
As the count value of the up-down counter reaches zero, the original feeding apparatus characterized by driving and controlling the rotation speed of the first motor in accordance with the count value. According to claim 2, wherein the control means, the Rukoto subsequently Gyosu control the rotational speed of said first motor to said count value to zero after the count value of the up-down counter becomes zero Characteristic document feeder. According to claim 1, wherein, while the original is conveyed across the second feeding means and the first feeding means, the feeding speed of the first feeding means, said second sheet A document feeding device, wherein the document feeding device is controlled so as to coincide with a feeding speed of a feeding unit.

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