JP2000013561A - Sheet carrier and device and method for reading image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader capable of continuing read operation without stopping a device, when a sensor for detecting the length in a carrying direction of a sheet fails. SOLUTION: When an original is set on an original tray and a copy key is depressed, whether or not an original rear end detection sensor is a fault is discriminated, and when the original rear end sensor is not the fault, whether or not the original rear end detection sensor is off is discriminated. When the original rear end detection sensor is off, a copying processing is performed in a first rough read mode. Meanwhile, when the original rear end detection sensor is at fault or in the case that the original read end detection sensor is on, the copying processing is performed in a second rough read mode. When the original rear end detection sensor is the fault, since the sensor output becomes an on state at all times, the original is read at the read position of a large size sheet by the second rough read mode regardless of a set original size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying apparatus for conveying a sheet such as a document, an image reading apparatus for reading an image recorded on the conveyed sheet, and a method.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus having a sheet conveying device, a method in which a sheet is conveyed to an image reading position by a sheet conveying device and then a scanner is scanned to read an image (hereinafter referred to as a fixed reading method) is generally used. Has been adopted.

In this fixed reading method, when one set of copies is obtained from a sheet bundle set in a sheet conveying device, the sheet exchange by the sheet conveying device is not completed while the scanner returns to the image reading start position. Thus, the productivity of the image forming apparatus cannot be fully exhibited, and it is necessary to convey the sheet at a high speed on the sheet conveying apparatus side.

However, when a sheet is conveyed at a high speed,
Not only does the conveying noise in the sheet conveying device increase, but there is a risk that the sheet itself may be damaged.

For this reason, a method has recently been proposed in which a scanner is fixed at a predetermined position and an image is read while a sheet is conveyed by a sheet conveying device (hereinafter referred to as a flow reading method). In this flow reading method, the reading position is changed after detecting whether or not the sheet placed on the tray is a large size sheet based on the length in the sheet conveying direction. The determination of the image reading position is performed by detecting the length of the placed sheet in the sheet conveying direction by a reflection type sensor mounted on the tray.

[0006] In this flow reading method, since the exchange of the sheet and the image reading are performed at the same time, there is an advantage that high productivity can be obtained by reducing the sheet interval even if the transport speed is reduced.

[0007]

However, in the above-mentioned conventional image reading apparatus, if the sensor for detecting the length of the sheet in the conveying direction fails, the sheet cannot be conveyed by itself. There was a problem.

Therefore, the present invention provides a sheet conveying apparatus, an image reading apparatus, and a method capable of continuing a reading operation without stopping the apparatus when a sensor for detecting the length of the sheet in the conveying direction has failed. The purpose is to do.

[0009]

According to a first aspect of the present invention, there is provided a sheet conveying apparatus for conveying a sheet from which an image is read by an image reading apparatus to an image reading position. , A placement unit for placing the sheet, a detection unit for detecting a length of the placed sheet in the conveyance direction, and the image reading position according to the length of the detected sheet in the conveyance direction. Transport means for transporting the sheet, wherein the transport means transports the sheet to an image reading position corresponding to a sheet of a predetermined size when the detection means has failed.

According to a second aspect of the present invention, in the sheet transporting apparatus according to the first aspect, the image reading position corresponding to the sheet of the predetermined size is an image reading position corresponding to the sheet of the maximum size. Features.

According to a third aspect of the present invention, there is provided an image reading apparatus, comprising: detecting means for detecting a length of a sheet conveyed to an image reading position in a conveying direction; Setting means for setting an image reading position;
Reading means for reading an image recorded on the sheet at the set image reading position, the setting means,
When the detecting means breaks down, an image reading position is set according to a sheet of a predetermined size.

According to a fourth aspect of the present invention, in the image reading apparatus according to the third aspect, the image reading position set according to the sheet having the predetermined size is an image reading position corresponding to the sheet having the maximum size. There is a feature.

According to a fifth aspect of the present invention, in the image reading apparatus according to the third aspect, a sheet conveying means for separating sheets one by one from a sheet bundle placed on a tray and conveying the sheets to the image reading position. Wherein the reading means comprises:
The image recorded on the sheet conveyed to the image reading position is read in a fixed state.

According to a sixth aspect of the present invention, in the image reading apparatus according to the third aspect, the image reading apparatus is applied to an image forming apparatus.

According to a seventh aspect of the present invention, in the image reading method, the length of the sheet conveyed to the image reading position in the conveying direction is detected by a sensor, and the image reading is performed according to the detected length of the sheet in the conveying direction. When a position is set and an image recorded on the sheet is read at the set image reading position, if the sensor fails, the image reading position is set according to a sheet of a predetermined size. .

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a sheet conveying apparatus, an image reading apparatus and a method according to the present invention will be described. The image reading device of the present embodiment is applied to a copying machine.

[Entire Apparatus] FIG. 1 is a diagram showing the configuration of a copying machine. The copier includes a copier main body 1 including an image input unit 200 (hereinafter, referred to as a reader unit) and an image output unit 300 (hereinafter, referred to as a printer unit), and a document feeder disposed above the copier main body 1. (ADF: Automatic Do
cument Feeder) 2.

The reader unit 200 optically reads an image recorded on a document P placed on a platen glass (platen) 3 which is a reading position of the copying machine body 1, and inputs the image as image data by photoelectric conversion. A scanner unit 204 having a platen 3, a lamp 202 and a mirror 203, mirrors 205 and 206, and a lens 20.
7, an image sensor 208 and the like.

The printer unit 300 outputs an image read by the reader unit 200 on a sheet. FIG. 2 is a diagram showing a configuration of the printer unit 300. In the figure, 302a
Denotes an upper cassette. Sheets in the cassette are separated and fed one by one by the action of a separation claw and a feeding roller 301, and are guided to registration rollers 306.

Reference numeral 302b denotes a lower cassette. Sheets in the cassette are separated and fed one by one by the action of a separation claw and a feeding roller 303, and are guided to registration rollers 306.

A manual guide 304 guides sheet materials one by one to a registration roller 306 via a roller 305. Reference numeral 308 denotes a sheet stacking device (deck type) having a middle plate 308a which is moved up and down by a motor or the like, and the sheets on the middle plate are separated and fed one by one by the action of a feeding roller 309 and a separating claw. It is guided to the transport roller 310.

Photosensitive drum 312, reading optical system, developing unit 3
14, the transfer charger 315 and the separation charger 316 constitute an image forming unit. Reference numeral 317 denotes a conveyance belt for conveying the sheet material on which an image is formed, 318 denotes a fixing device, 319 denotes a conveyance roller, and 320 denotes a flapper. The sheet material on which the image is formed is guided to the discharge roller 321 by the flapper 320, and is conveyed into the sorter 322. The sorter 322 includes a non-sort tray 322a, a sort bin tray 322b,
It has a non-sort tray discharge roller 322c and a sort bin tray discharge roller 322d, and the non-sort tray and the sort bin tray move up and down to sort sheets one by one. Incidentally, a discharge tray may be mounted in place of the sorter.

Reference numeral 400 denotes an intermediate tray which stocks a sheet material on which an image has been formed once when forming an image on both sides of the sheet material or when forming an image on one side of the sheet material (multiple). 401 is a conveyance roller, 402 is a conveyance belt, 403 is a flapper, 404 is a conveyance belt,
405 is a transport roller. Pass 4 for duplex copy
06 to the intermediate tray 400. The image side of the sheet is facing up. Pass 4 for multiple copies
07 to the intermediate tray 400. The image side of the sheet is facing down.

The sheet material stacked on the intermediate tray 400 includes auxiliary rollers 409 and 410, a forward / reverse separation roller pair 4
The sheets are separated one by one from below by the action of 11 and re-fed. The re-fed sheet materials are transport rollers 413, 4
It is guided to the image forming unit via the rollers 14 and 415 and the roller 310. After the image formation, it is discharged in the same manner as described above.

In accordance with the number of copies set for one document placed on the platen, first, single-sided copies are made, and these are stacked on the intermediate tray 400. After that, the original is reversed on the platen and guided again on the platen, and this image is read by the number of copies. The read image is formed on a sheet material re-fed from the intermediate tray 400 every time the image is read. They are sorted by the sorter 322 in page order.

On the other hand, there is also a method in which only one copy is created each time a document is cycled by the document feeder 2. According to this method, even when a plurality of copies are made, a copy group having the same page order can be obtained in order, so that a necessary number of copies can be obtained separately without a sorter. When making a two-sided copy in this way, both sides of one document are continuously read, and then copied and ejected on both sides of the sheet material.
Thereafter, the same operation is repeated several times on both sides of the next original, thereby obtaining a divided double-sided copy group.

The document transport device 2 transports a document to a predetermined reading position of the copying machine main body 1. FIG. 3 is a diagram illustrating the configuration of the document feeder 2. Document feeder 2
Has a document tray 4 on which documents are placed, and a drive roller 36 and a turn roller 37 below it.
The wide belt 7 wound around is arranged. The document P (see FIG. 4) placed on the document tray 4 is sequentially separated from its uppermost sheet and transported to a platen glass (platen) 3 which is a reading position of the copying machine main body 1. FIG. 4 is a diagram showing the position of the flapper provided in the transport path.

The wide belt 7 is in contact with the platen 3 and places the sheet document P conveyed from the document tray 4 at a predetermined position on the platen 3 or discharges the sheet document P placed on the platen 3. It is carried out to the paper tray 10. The originals are placed on the original tray 4 in the order of 1 page (2 pages), 3 pages (4 pages),... From the top.

[Configuration of Document Tray 4] The document tray 4 is for stacking sheet-shaped documents, and a pair of width-direction regulating plates (regulation guides) 29 are slid on the document tray 4 in the width direction of the document P. It is arranged freely. The width direction regulating plate 29 regulates the width direction of the document P placed on the document tray 4 and secures stability when the document P is fed. The width direction regulating plate 29 has five slide switches SW0 to SW0.
An SW 4 is provided to detect a width of the document in a direction orthogonal to the sheet conveying direction.

A stopper 21 is provided at the downstream end of the document tray 4 in the transport direction so as to be rotatable. The sheet document P set on the document tray 4 is moved by the protruding stopper 21. It is restricted so that it cannot advance downstream (see FIG. 5).

[Sensor on Document Tray 4] Stopper 21
A document set detection sensor 40 (40a, 40b) composed of a transmissive optical sensor that detects that the sheet document bundle P has been set is provided near the upstream portion of the document (see FIG. 3).

In the middle of the document tray 4, a document trailing edge detection sensor 41 for determining whether the set document is a half size document is provided. It consists of a reflection type optical sensor, is arranged at a distance of 225 mm from the stopper 21, and turns on when a long original (large size sheet) is set.

When the document trailing edge detection sensor 41 fails, its sensor output is always turned on, that is, in a paper-existing state, and the reading by a scanner described later depends on the large sheet size. The reading is performed at the reading position.

A final document detection sensor 43 composed of a reflection type optical sensor is provided between the document set detection sensor 40 and the document rear end detection sensor 41, and determines whether the document being transported is the final document. Is determined.

A paper width detection sensor 44 is provided below the document tray 4 to detect the length of the document bundle P set on the document tray 4 in the sheet conveying direction. Based on the length in the sheet conveyance direction detected by the paper width detection sensor 44 and the length in the direction orthogonal to the sheet conveyance direction detected by the above-described slide switches SW0 to SW4, the document is set on the document tray 4. The size of the document bundle P is determined.

[Feeding / Separating Mechanism] FIG.
FIG. 3 is a diagram illustrating a sheet feeding / separation mechanism viewed from the direction of line A. FIG.
FIG. 3 is a diagram illustrating members such as a swing arm 53, a sheet feeding roller 5, and a lifting arm 51. FIG. 7 is a plan view showing the sheet feeding / separation mechanism. A swing arm 53 is provided above the document tray 4.
The lift arm 51 is configured to be swingable about the rotation width center C1 of the separation / conveyance roller 8.

The swing arm 53 is swing-restricted by an arm shaft 51c that is supported by the support plates 51a and 51b in front and behind the lifting arm 51.
Is provided.

Normally, the sheet feeding roller 5 is restrained by the arm shaft 51c and stands by at a home position (see FIG. 5) above the separation upper guide plate 52 which is restrained by the pin 51g. Does not inhibit Here, the lifting arm 51 is connected to a swing motor 10 described later.
3 (see FIG. 3).

The elevating arm 51 rotates about the center C1 of the rotating shaft, and is movable from the position shown in FIG. 5 to the position shown in FIG.
FIG. 8 is a diagram showing the operation of the paper feed / separation mechanism. The paper feed roller 5 is provided at the tip of the swing arms 57 and 53 that swing about the rotation axis center C1 as described above. The swing arms 57 and 53 move down by their own weight with the movement of the lift arm 51, and the paper feed roller 5 lands on the uppermost sheet of the document P and stops (the position in FIG. 9). FIG. 9 is a diagram showing the operation of the paper feed / separation mechanism. By rotating the paper feed roller 5 in this state, the original is sequentially conveyed from the uppermost sheet. The upper separation guide plate 52 is restrained at the position shown in FIG. 8 by a stopper (not shown).

In the state of FIG. 9, the swing arms 57, 5
Arm shaft 51c and swing arms 57, 5 supporting
The engagement with the roller 3 is released when the paper feed roller 5 lands on the document surface. 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 displacement is determined by the first swing arm flag 54 and the second swing arm flag 5, which are a part of the swing arms 57 and 53.
5 and a first swing position sensor 46 and a second swing position sensor 47 attached to the lifting arm 51. When the states of the first swing position sensor 46 and the second swing position sensor 47 change from the non-detection state to the detection state (see FIG. 9), the swing arms 57 and 53 receive stop control.

In this state, the swing arms 57 and 53 and the paper feed roller 5 are placed by their own weight on the sheet bundle stacked on the document tray 4, so that a stable feeding force is always applied to the sheet document P. It is possible to give.

The raising / lowering arm 51 is driven by a swing motor 103 (stepping motor), and the raising / lowering arm 51 is in any state between the state shown in FIG. 5 and the state shown in FIG. 8 (FIG. 10). Position). FIG.
0 is a diagram showing the operation of the paper feed / separation mechanism.

Above the separation roller 6, a paper feed roller home sensor 45 composed of a transmission type optical sensor is provided with a fixed support plate 56.
When the elevating arm 51 is at the home position, the elevating arm flag 51d provided on the swing arms 57 and 53 shields the sensor optical path of the paper feed roller home sensor 45 from light.

As described above, the lift arm 51 is provided with the first swing position sensor 46 and the second swing sensor 47 which move integrally with the lift arm 51, and the swing arms 53 and 57 respectively swing. The first swing arm flag 54 and the second swing arm flag 55 extending in the directions are detected.

The state shown in FIG. 10 shows the standby position during continuous paper feeding. At the time of continuous paper feeding, the swing arms 57 and 53 do not need to return to the home position (the position in FIG. 5), so that the feed roller 5 is intermediately stopped at a position where the feeding roller 5 is separated from the original bundle by the minimum amount (about 3 to 5 mm). Is controlled as follows.

By adopting the above configuration, it is 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 document P is reduced.
Contributes to improving paper feeding performance. At the same time, the time until the start of the subsequent sheet feeding can be shortened, and sheet feeding control with a shorter sheet feeding interval can be performed.

When the feeding operation is started in a state in which the paper feed roller 5 is bound by the impact when the paper sheet P lands on the sheet document P, the pressure balance of the front and rear feed rollers against the sheet document P is lost, and the paper feeding time is reduced. The possibility of generating skew is increased.

As shown in FIG. 7, a plurality of feed rollers 5 arranged in the width direction each have an independent suspension structure, and are easily equalized to the sheet bundle of originals P. It is possible to plan.

Downstream of the shutter 21 in the transport direction, there is provided a separation section including the well-known separation belt 6 and the separation transport roller 8, and performs the separation operation by rotating in the direction of the arrow (see FIG. 9).

[Conveying Mechanism] FIG. 11 is a diagram showing a configuration of a document feeding path. Document feed paths (a), (b), and (c) are formed from the document tray 4 to the platen 3, and these document feed paths (a), (b), and (c) are bent (curved downward). The sheet original P is guided to the platen 3 by being connected to the conveyance path (d) on the platen 3.

The document transport path (a) is a transport path in which the document separated by the separation unit is transported downstream by the separation transport roller 8.

From the original feeding path (b) to the reverse feeding path (h),
(F) and (i) are extended so that the original can be turned over before the original is conveyed to the platen 3.

The original reversed in the reversing feeding paths (h), (f) and (l) is switched back, passes through the original feeding / discharging path (e), is conveyed to the platen 3, and is placed thereon.

The document reversing path (G) is branched from the reversing feeding path (F) so that the document reversing path (B) can be merged with the document feeding path (B). G), c)
The document on the platen 3 can be switched back and upside down by using, and can be returned to the platen 3 again.

The original conveyed to the platen 3 is read after the image reading is completed, and then the original is conveyed on the platen (d).
The document is discharged to the paper discharge tray 10 through the document discharge path (N) shown in FIG.

An openable manual document tray 14 is provided on the right side of the ADF 2 shown in FIG. 3, and can feed the set document P (single document) to the platen 3 through a manual feed path. It has become.

[Arrangement of Rollers] A first feeding roller 16 is provided between the document feeding paths (a) and (b) (see FIG. 11), and a separating section (separating belt 6, separating and conveying roller) is provided. The document sent from 8) is restrained to prevent the document from being skewed.

The separation / conveyance roller 8 is provided with a one-way mechanism to reduce the conveyance load when the original is pulled out of the separation section by the first feeding roller 16.

A second feeding roller 9 is provided at the junction of the document feeding paths (a), (b) and (c) and the document reversing path (g). Then, a loop is formed in the arrived sheet document P to prevent skew of the sheet document P.

In the reversing feed paths (h), (f), and (li),
A first reversing roller 17 and a second reversing roller 18 are provided, and transport the document P along a loop-shaped reversing path.

On the right side of the ADF 2, a manual feed roller 1 is provided.
The document feeder 3 feeds a document set on the manual document tray 14 from right to left.

A manual feed registration roller 11 is provided between the manual feed roller 13 and the platen 3 to prevent a skew by forming a loop on a document fed manually. The manual registration rollers 11 relay the discharge of the original from the platen 3.

A discharge roller 12 is provided in the document discharge path (nu), and the discharged document P is discharged from the discharge tray 10.
To be discharged.

[Intra-path flapper] In FIG. 4 showing the position of the flapper provided in the conveyance path, a reversing paper feed flapper 22 is provided downstream of the second feeding roller 9 in the conveyance direction. The path between the path (c) and the reverse feeding path (h) is switched. When the original P is transported to the reverse feeding paths (H), (F), and (I), the flapper 22 is in the state of the solid line in the figure, and the original P is transported to the original feeding paths (C) and (D). In this case, it swings to the state shown by the chain line in the figure.

A reversing flapper 23 is provided downstream of the second reversing roller 18 in the transport direction, and switches between a reversing feeding path (R) and a document reversing path (G).

When reversing the original P conveyed from the original feeding path (b) and the reverse feeding path (h), the reversing flapper 23 is in the state of the solid line in FIG. When the document is reversed through the document feeding / discharging path (e), the reversing feeding path (f), and the document reversing path (g), it swings to the position indicated by the chain line in the figure.

A one-way flapper 24 (to which a mylar or the like is attached) is provided at the junction of the reversing feed path (h) and the document supply / discharge path (e) near the upstream of the first reversing roller 17. The one-way flapper 24 serves as a guide when the document P is transported from the reversing feeding path (h) to the reversing feeding path (f).
When the document P is conveyed from (f) to the platen 3 through the document supply / discharge path (e), the document P serves to prevent the document P from entering the reverse supply path (h) backward.

On the platen 3 side of the reversing supply / discharge path (e), there is provided a supply / discharge flapper 25 interlocked with the reversal sheet supply flapper 22, and conveys the document P to the platen 3 from the document supply / discharge path (e). In this case, the platen 3
Is prevented from colliding with the end of the platen 3. When the document P is transported from the platen 3 to the document supply / discharge path (e), the document P can be swung to a position indicated by a dashed line in FIG.

A paper discharge flapper 26 is provided between the right end of the platen 3 and the manual feed registration roller 11 (FIG. 3).
When the original P is transported from the manual feed path (L) to the platen 3, the original P is located at the solid line position in the drawing, and the leading end of the original P entering the platen 3 is prevented from colliding with the end of the platen 3. I have. Document P from platen 3 to document discharge path (nu)
Is ejected, the document can be swung to the position indicated by the dashed line in FIG.

A one-way manual flapper 27 is provided at the confluence of the document discharge path (N) and the manual feed path (R), and is used when the document P is discharged from the platen 3. The document is prevented from entering the document.

A manual shutter 28 is provided in the vicinity of the downstream of the manual paper feed roller 13 in the transport direction, and the manual document set on the manual document tray 14 is discharged by the manual registration roller 11 while the original P after copying is being discharged. To prevent entry. At this time, the conveying force is set low so that the manual feed roller 13 and the original slip.

[Arrangement of Sensors in Path] Separating and Conveying Roller 8
A separation sensor 30 composed of a transmission type optical sensor is provided between the first feed roller 16 and the first feed roller 16 (see FIG. 3), and detects the original P conveyed by the separation conveyance roller 8. At the same position in the transport direction as the separation sensor 30 and at a position separated by a predetermined distance in the thrust direction, a skew detection sensor 31 composed of a transmission type optical sensor is provided. The skew detection sensor 31 and the separation sensor 30 are used to detect the skew amount of the fed document.

In the vicinity of the downstream side of the first feed roller 16, there is provided a mixed detection sensor 32 for detecting a document by moving a flag. It is configured to detect that a document is set on the document tray 4.

In the vicinity of the upstream of the second feed roller 9, a paper feed sensor 35 composed of a transmission type optical sensor is provided.
The front end and the rear end of the document P that has passed through any one of the document feeding paths (a), (b), (c) and the document reversing path (g) are detected.

A registration sensor 39, which is also a transmission type optical sensor, is provided downstream of the feed roller 9, and controls the stop position of the document P by detecting the rear end of the document P.

The reversing conveyance path (e) is provided with a reversing sensor 50 composed of a transmission type optical sensor.
The original P discharged from the printer or the original P entering the platen 3 is detected.

A reversing detection sensor 33 for detecting the document P by moving the flag is provided in the reversing feeding path (R), and the document P is led to the reversing feeding path (R) by switching the reversing flapper. Detect that.

A manual registration sensor 34, which is a transmission type optical sensor, is provided near the downstream of the manual registration roller 11 in the sheet discharging direction. The document P discharged to the document discharge path (nu) is detected.

On the side of the manual feed tray 14 of the manual feed roller 13, there is provided a manual feed detection sensor 60 for detecting the original P by moving a flag, and detects that a document is set on the manual feed tray 14. .

[Drive System] The drive system of the document feeder 2 will be described. FIG. 3 shows a drive system such as a motor and a solenoid for driving various transport rollers and a flapper.

The separation motor 100 drives the separation section (separation / conveyance motor 8 and separation belt 6) in the direction of the arrow in FIG. 5, and also drives the paper feed roller 5 via the separation clutch 106. In the present embodiment, a PLL is used as the separation motor 100.
A controlled DC brush motor is used.

A clock plate 100a comprising a plurality of slits is provided on the motor shaft of the separation motor 100.
When the separation motor 100 is rotated by the slit and the separation clock sensor 100b including a transmission type optical sensor, a clock pulse proportional to the rotation speed is generated.

The transport motor 101 is a stepping motor that can rotate forward and reverse, and drives the second feed roller 9, the first reverse roller 17, and the second reverse roller 18.

The driven roller shaft of the second feeding roller 9 is provided with a clock plate 101a composed of a plurality of slits, and the transport motor 101 is controlled by the slits and an inverted clock sensor 101b composed of a transmission type optical sensor. When rotated, a clock pulse proportional to the number of rotations is generated.

When a slip occurs while the document P is being conveyed by the second feeding roller 9, the slip amount can be measured from the number of clock pulses and the number of drive clocks of the conveying motor 101.

The belt motor 102 is composed of a stepping motor that can rotate forward and backward, and drives the wide belt 7 and the manual registration roller 11. The driving force of the belt motor 102 is transmitted to the wide belt 7 via the drive roller 36, and further transmitted to the manual registration roller 11 via the wide belt 7 and the turn roller 37. in this case,
The conveying speed of the original on the platen 3 is set to be equal to the conveying speed of the manual registration roller 11.

The swing motor 103 is a stepping motor that can be rotated in the forward and reverse directions, and drives the swing (elevation) arm 53 of the paper feed roller 5.

The discharge motor 104 is an FG servo control type D
A C motor drives the discharge roller 12 and the manual feed roller 13. A clock plate 104a composed of a plurality of slits is provided on the motor shaft of the paper discharge motor 104. The paper discharge motor 104 is formed by the slits and a paper discharge clock sensor 104b composed of a transmission type optical sensor.
When 4 rotates, a clock pulse proportional to the number of rotations is generated.

The stopper solenoid 105 is connected to the document tray 4
Then, the stopper 21 at the sheet feeding end is driven. Stopper 21
Is in the solid line position in FIG. 7 when it is off, and swings to the chain line position in FIG. 7 when it is on.

The separation clutch 106 is connected to the separation motor 100
Is transmitted to the paper feed roller 5, the separation belt 6, and the separation conveyance roller 8 or cut off.

The path switching solenoid 107 drives the reverse sheet feeding flapper 22 and the supply / discharge flapper 25. When the path switching solenoid 107 is off, the reversing sheet feeding flapper 22 and the supply / discharge flapper 25 are respectively at the solid line positions in FIG. 4, and when the path switching solenoid 107 is on, the reversing sheet feeding flapper 22 and the supply The discharge flapper 25 swings to the position indicated by the dashed line in FIG.

The reverse flapper solenoid 108 drives the reverse flapper 23. When the reverse flapper solenoid 108 is off, the reverse flapper 23 is at the solid line position in FIG. 4, and when turned on, swings to the chain line position in FIG.

The discharge flapper solenoid 109 drives the discharge flapper 26 and the manual shutter 28. When the solenoid is off, the paper discharge flapper 26 and the manual feed shutter 28 are at the dashed line position in FIG. 3, and when turned on, swing to the solid line position in FIG.

[Original Reading Position] FIG.
FIG. 7 is a diagram illustrating an upper document reading position. There are three document reading positions R1, R2, and R3 in the figure, and one of them is selected according to the document transport mode and the size of the document to be transported.

The reading position R1 is a reading position in the double-sided original mode. With the document placed on this position with the document edge aligned, the scanner unit 20
4 is scanned to perform image reading (fixed reading mode).

The reading position R2 is a reading position for a half-size original in the one-sided original mode. The scanner unit 204 of the copying machine main body 1 is fixed at this position, and the image is read while the document is being conveyed (flow reading mode).

The reading position R3 is a reading position of the original when the large-size and half-size originals are vertically fed in the single-sided original mode. Copying machine body 1
The scanner unit 204 is fixed, and an image is read while a document is being conveyed (flow reading mode).

In FIG. 12, L1 is the second feed roller 9
, The distance from the nip point of the second feeding roller 9 to the reading position R2, and L3 the distance from the nip point of the second feeding roller 9 to R3.

L4 shown in FIG. 13 is the distance from the reading position R1 to the stop position for standby of the half-size document placed on the left side of the platen 3. FIG. 13 is a diagram showing a reading position of a document. 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 between the trailing edge of the preceding document and the trailing edge of the succeeding document (hereinafter,
This is referred to as the sheet distance). L7 is the distance from the reading position R1 to the manual registration roller 11.

The length of the half-size document in the transport direction is Lp
When h is set, the stop position of the half-size document is controlled so that the relationship of Expression (1) holds.

L7 <[L4 + 2 × L6 + Lph] L2> [L5-Lph] (1) As a result, as shown in FIG.
n and Pn-1 are stopped, the preceding original P
The rear end of n-2 passes through the nip of the manual registration roller 11, and the rear end of the document Pn waiting for image formation is the second end.
Through the nip of the feed roller 9.

Next, the operation of the document feeder will be described. At the time of transport, first, a separation operation common to each document transport mode is performed, and then, a different operation is performed for each document transport mode.

The separation operation and the operation unique to each document transport mode will be described separately. Here, in order to clarify the order of conveyance, a document conveyed earlier is referred to as a “preceding document”, and a document conveyed later is referred to as a “subsequent document”.

[Separation operation] Original set sensors 40a, 4a
When the document bundle on the document tray 4 is detected by 0b, the pre-separation operation is started. That is, the paper feed roller 5
Descends and lands on the document stack. The originals stacked on the original tray 4 are referred to as an original P1, an original P2, an original P3,. If the order of the originals is not specified, the original P
And

When copying conditions are input on the operation unit of the copying machine and the start key is pressed, the size of the document is detected by a sensor on the platen 3. Further, the stopper 21
Is operated by the stopper solenoid 105, the path of the document bundle is opened. The document bundle advances from the document P1, which is the uppermost sheet, to the downstream portion after being fed by the paper feed roller 5.

A separation conveyance roller 8 and a separation belt 6 constituting a separation section are provided downstream of the stopper 21. The separation roller P rotates in the direction of an arrow and moves out of the document tray 4 one by one. And transported further downstream.

The document P that has passed through the separation unit is separated by the separation sensor 3
0, after skew is detected by the skew sensor 31,
The sheet is conveyed while being restrained by the first feed roller 16.

When the original is conveyed by the first feed roller 16, the paper feed roller 5 is raised, and then the separation clutch 106 is turned off, and the drive of the separation belt 6 and the separation conveyance roller 8 is cut off and stopped. I do. Since the separation / conveyance roller 8 is constituted by a one-way roller, the separation / conveyance roller 8 rotates (rotates) following the movement of the document P being conveyed.

The document P is conveyed only by the first feeding roller 16 and hits the stopped second feeding roller 9 to perform a known skew feeding.

When the skew feeding is completed, the first feed roller 1
6 and the second feeding roller 9 start rotating simultaneously. The first feed roller 16 and the second feed roller 9 are speed-controlled synchronously so that their transport speeds match.

As a result, the separation operation ends. The subsequent operation differs depending on the document transport mode, and will be described separately for each mode. That is, the operation after the separation operation is
A description will be given separately for each document transport mode such as a single-side fixed reading mode, a half-size single-sided document transport mode, a large-size single-sided document transport mode, a half-size double-sided document transport mode, a large-size double-sided document transport mode, and a manual-feed document transport mode.

[Simplex Fixed Reading Mode] FIG. 14 is a diagram showing the flow of a document in the simplex fixed reading mode. In the single-sided fixed reading mode, the path switching solenoid 107 is turned off, so that the transport path is on the side of the document feeding path (C), and the preceding document P1 enters the platen 3, but the preceding document P1 When the rear end of P1 passes through the nip point of the first feeding roller 16, the separation clutch 106 is turned on, and the feeding of the next original P2 by the feeding roller 5 is started.
Before the preceding document P1 enters the platen 3, the transport speed of the wide belt 7 is controlled to match the speed of the second feeding roller 9.

When the preceding document P1 is placed with the document edge aligned with the reading position R1, the image is read by the scanning of the scanner unit 204 of the copying machine body 1.
At this time, the leading end of the next document P2 is abutted against the stopped second feeding roller 9 to perform skew feeding.

When the image reading of the preceding document P1 by the scanning of the scanner unit 204 is completed, the next document P2 becomes
The leading document P1 is placed with the document edge aligned with the reading position R1, the preceding document P1 is transported in the rotation direction of the transport belt 7, and the leading edge of the succeeding document P3 is abutted against the stopped second feeding roller 9 and skewed. Takes place. Thereafter, the same operation is performed for all subsequent documents.

[Half-size one-sided original transport mode] FIG.
5 and 16 are diagrams showing the flow of a document in the single-sided document transport mode. When the original transport mode is the one-sided original transport mode, the path switching solenoid 107 is controlled to be turned off, so that the transport path is on the original feed path (C), and the preceding original P1 enters the platen 3. To go. Before the preceding document P1 enters the platen 3, the transport speed of the wide belt 7 is controlled to match the speed of the second feeding roller 9.

When the trailing edge of the preceding document P1 passes through the nip point of the sheet feeding roller 5, the feeding roller 5 descends again and prepares for the operation of feeding the succeeding document P2.

Further, when the trailing edge of the preceding document P1 passes through the nip point of the feed roller 5 for punching 1, the separation clutch 106 is turned on, and the feeding of the succeeding document P2 by the paper feeding roller 5 is started (FIG. 15 ( a)).

When the trailing edge of the preceding document P1 passes through the nip of the second feeding roller 9, the second conveying roller 9 is stopped. The subsequent document P2 is rapidly accelerated after the start of paper feeding by the paper feeding roller 5, and when the second conveyance roller 9 stops, the paper feeding sensor 3
5 is controlled. When the paper feed sensor 35 is turned on by the succeeding document, control for skew feeding is performed as in the case of the preceding document P1.

At this time, the preceding document P1 has entered the transport path (d) on the platen 3 and is independently transported by the wide belt 7, and when the trailing edge has advanced a predetermined distance after passing through the paper feed sensor 35, The document P1 temporarily stops (see FIG. 15B).

At this time, the distance between the leading end of the document P1 and the second reading position R2 is controlled to be L5.
The distance L8 between the rear end of the document P1 and the nip point of the second feeding roller 9 is represented by L8 = L2-L5-conveyed document size L2: distance from the reading position R2 to the second feeding roller. It is configured to be distance and positive. That is, the rear end of the document P1 has passed the nip of the second feeding roller.

The ADF 2 temporarily stops the preceding original P1, outputs a transport completion signal 120 to the copying machine main body, and waits for the input of the transport start signal 121.

When the conveyance start signal 121 from the copying machine main body is received and the skew feed control of the succeeding original P2 is completed,
The wide belt 7 is activated to convey the preceding original P1 at the image forming speed.

When the distance between the trailing edge of the preceding document P1 and the leading edge of the succeeding document P2, that is, the sheet-to-sheet distance, becomes a predetermined distance, the second feeding roller 9 is activated, and the same as the preceding document P1.
At the image forming speed.

When the conveying speeds of the wide belt 7 and the second feeding roller 9 coincide with each other, the activation and acceleration of the second feeding roller 9 are controlled so that the sheet distance becomes L6.

When the preceding original P1 reaches the reading position R2, the ADF 2 outputs an image destination reaching signal 122. The copier body 1 receives this and starts reading an image of the preceding original P1.

FIG. 15C shows a state after the image reading of the document P1 is completed. The document P1 is stopped after being conveyed at a predetermined position (L9) after the reading is completed. At this time, the succeeding original P2 is at the reading position R2.
At a distance L5 from the vehicle. Further following manuscript P
3 stands by while maintaining a loop for skew removal by the second feeding roller 9.

In this state, when the conveyance start signal 120 is input from the copying machine main body 1, an image of the original P2 is formed. FIG. 16A shows the position of the original in the path while the image of the original P2 is being read. The document P1 is conveyed by the wide belt 7, the manual registration roller 11, and the paper discharge roller 12. At this time, the conveying speed of the wide belt 7 and the conveying speed of the manual registration roller 11 are configured to be equal. The transport speed of the discharge roller 12 is controlled to be equal to or slightly faster than these speeds.

FIG. 16B shows a state when reading of the succeeding original P2 is completed. After the completion of reading, the wide belt 7 stops, so that the following originals P2, P3
Is stopped on the platen 3. Since the trailing end of the preceding document P1 has already passed through the nip of the manual registration roller 11, it is independently conveyed by the paper discharge roller 12 and
Discharged to zero.

[Large-size one-sided original transport mode] FIG.
FIGS. 7 and 18 show the flow of a document in the large-size one-sided document transport mode. As in the case of the small (half) size single-sided document transport mode, the path switching solenoid 107 is controlled to be off, so that the transport path is on the document feed path (c). Prior document P1 is platen 3
When the trailing edge of the preceding document P1 passes through the nip point of the separation / conveyance roller 8, the feeding roller 5 descends again and prepares for the feeding operation of the following document P2.

Further, when the trailing end of the preceding document P1 passes through the nip point of the first feeding roller 16, the separation clutch 106 is turned on and the feeding of the succeeding document P2 by the feeding roller 5 is started. This state is shown in FIG.

When the trailing edge of the preceding document P1 passes through the nip of the second feeding roller 9, the second feeding roller 9 is stopped. The subsequent document P2 is rapidly accelerated after the start of sheet feeding by the sheet feeding roller 5, and when the second feeding roller 9 stops, the sheet feeding sensor 3
5 is controlled. When the feed sensor 35 is turned on by the succeeding document P2, control for skew feeding is performed in the same manner as in the case of the preceding document P1.

At this time, the preceding document P1 has entered the transport path (d) on the platen 3 and is independently transported by the wide belt 7. Then, when the trailing end advances a predetermined distance after passing through the paper feed sensor 35, the preceding original P1 stops temporarily (see FIG. 17B).

At this time, the distance between the leading edge of the document P1 and the third reading position R3 is controlled to be L5 as in the case of transporting the half-size document. The distance L10 from the rear end of the document P1 to the nip point of the second feeding roller 9 is represented by L10 = L3-L5-conveyed document size L3: distance from the reading position R3 to the second feeding roller 9, The value (L10) is configured to be positive. That is, the rear end of the document P1 has passed the nip of the second feeding roller.

The ADF 2 outputs a transport completion signal 120 to the copier main body 1 at the same time as stopping the preceding original P 1 once. Then, it waits for the input of the transport start signal 121.

When the conveyance start signal 121 from the copying machine main body is received, and the skew feeding control of the succeeding original P2 is completed, the wide belt 7 is started, and the wide original belt P7 conveys the preceding original P1 at the image forming speed. I do. When the preceding document P1 reaches the reading position R3, an image destination reaching signal 122 is output. The copier body 1 receives this and starts reading an image of the preceding original P1.

When the distance between the trailing edge of the preceding document P1 and the leading edge of the succeeding document P2, that is, the inter-paper distance has reached a predetermined distance,
The second feed roller 9 is activated, and the second feed roller 9 conveys the succeeding document P2 at the same image forming speed as the preceding document P1. At this time, when the conveying speeds of the wide belt 7 and the second feeding roller 9 match, the activation and acceleration of the second feeding roller 9 are controlled so that the sheet distance becomes L11.
This state is shown in FIG.

FIG. 18B shows a state after the image reading of the document P1 is completed. The succeeding document P2 is stopped on the platen 3. The sheet distance L11 is set to be greater than the distance from the leading edge of the succeeding document P2 to the nip point of the manual feed registration roller 11. Therefore,
When the succeeding document P2 is stopped, the trailing end of the preceding document P1 has already passed through the nip point of the manual feed registration roller 11, and the document P1 is independently conveyed and discharged by the discharge roller 12.

[Half size double-sided document transport mode] FIG.
FIGS. 9, 20, 21 and 22 show the flow of originals during double-sided original transport. The transport speeds of the second feeding roller 9 and the wide belt 7 are controlled to be constant except in special cases.

When the document transport mode is the duplex document transport mode, first, the reverse sheet feeding flapper 22 and the reverse flapper 2
Reference numeral 3 is at the position indicated by the solid line in FIG. 4, and the document P1 is guided to the reverse feeding paths (H), (F) and (L) (FIG.
reference).

When the rear end of the document P1 passes through the one-way flapper 24, the rollers 17 and 18 are rotated in the reverse direction to convey the document P1 in the reverse direction. Since the supply / discharge flapper 25 is at the solid line position in FIG. 4, the document P1 conveyed in the reverse direction is guided to the conveyance path (d) on the platen 3 (see FIG. 19B).

When the document is further conveyed a predetermined distance from the time when the rear end of the document in the conveyance direction is detected by the reversing sensor 50, the wide belt 7 stops. As a result, the document P1 is placed on the reading position R1 in the fixed reading mode (see FIG. 20A). In this state, the scanning scan of the second surface is performed by the scanner unit 204 of the copying machine body 1.

The path switching solenoid 107 is turned off around the time when the placing of the document P1 is completed. Thereby, the reversing sheet feeding flapper 22 and the supply / discharge flapper 25 swing to the position indicated by the chain line in FIG. Scanner unit 20 of copier body 1
When the reading scan of the second surface of the document P1 is completed by 4, the wide belt 7 rotates in the reverse direction, and the document P1 is transported to the document feeding / ejecting path (e). At this time, since the reversing flapper 23 swings and moves to the position indicated by the chain line in FIG. 4 simultaneously with the reverse rotation of the wide belt 7, the document P1 is guided to the document reversing path (g) (see FIG. 20B). ).

When the document is conveyed a predetermined distance from the time when the leading edge of the document is detected by the reversing sensor 50, the rotation of the wide belt 7 temporarily stops, and then changes from reverse rotation to normal rotation. When the leading end of the inverted document P1 approaches the transport path (d) on the platen 3, the transport speed of the second feed roller 9 and the transport speed of the wide belt 7 are controlled so as to match.

When the trailing edge of the preceding document P1 passes through the nip point of the second feeding roller 9, the second feeding roller 9 stops and waits for the arrival of the following document P2.

The preceding document P1 is independently conveyed by the wide belt 7. When the document is conveyed a predetermined distance from the time when the trailing edge of the document is detected by the paper feed sensor 35, the wide belt 7 stops. As a result, the document P1 is placed at the reading position R1 in the fixed reading mode. In this state, the scanning scan of the first surface is performed by the scanner unit 204.

Further, before and after the trailing edge of the preceding document is detected by the paper feed sensor 35, the separating operation of the succeeding document P2 is started, and the second feeding roller 9 performs the well-known skew feeding.

During the scanning of the first side of the original P1 by the scanner unit 204 of the copying machine body 1, the reversing operation of the succeeding original P2 is completed. The next original P2 after the inversion is in a standby state with the vicinity of the leading end thereof nipped by the first inversion roller 17 (see FIG. 21A).

When the scanning of the first surface of the preceding original P1 is completed, the first reversing roller 17 and the second reversing roller 1
8 starts rotating, and the wide belt 7 starts rotating forward. As a result, the preceding document P1 and the succeeding document P2 are placed on the platen 3 with a predetermined sheet distance (L12) apart (FIG. 2).
1 (b)).

When the scanning of the second side of the original P2 by the scanner unit 204 of the copying machine body 1 is completed, the preceding original P
As in the case of 1, the reversing operation of the succeeding document P2 is started, and the succeeding document P2 and the preceding document P1 are conveyed in the direction of the reversing feed path (e).

Here, since the inter-sheet distance L12 is set to an appropriate value, the rotation of the belt is temporarily stopped while the preceding original P1 is on the transport path (d) on the platen 3, and thereafter, the rotation of the wide belt 7 is stopped. The direction is switched. As a result, the originals P1 and P2 are again conveyed in the direction of the paper discharge roller 12 and stopped in the state shown in FIG. And
In this state, reading scanning of the first surface of the document P2 starts. At this time, the distance between the document P1 and the document P2 is L1
It becomes 3. In addition, it is also possible to control so as to be L12. At this time, the succeeding original P3 is
As in the case of the document P2 shown in (a), the document is on standby while being nipped by the first reversing roller 17.

When the scanning of the first surface of the original P2 is completed, the first reversing roller 17 and the second reversing roller 18 are read.
, The forward rotation of the wide belt 7, and the rotation of the paper discharge roller 12 are started. As a result, the subsequent document P3, the document P2 for which image reading has been completed, and the document P1 are simultaneously conveyed.

When the wide belt 7 stops and the placement of the second surface of the succeeding document P3 is completed, the rear end of the preceding document P1 has passed through the nip of the manual feed registration roller 11. Therefore, the preceding document P1 is thereafter conveyed alone by the paper discharge roller 12 and discharged to the paper discharge tray 10 (FIG. 2).
2 (b)). This is achieved by setting the sheet distance to L13.

The above operation is continuously performed, and the final document Pn
When the scanning for reading the first surface is completed, the final document Pn and the final previous document Pn-1 are arranged on the platen 3 and are discharged at one time by the continuous operation of the wide belt 7.

[Large-size double-sided document transport mode] FIG.
3, FIG. 24, FIG. 25, and FIG. 26 are diagrams showing the flow of a document when a large-size double-sided document is conveyed. The transport speeds of the second feeding roller 9 and the wide belt 7 are controlled to be constant except in special cases.

When the document transport mode is the double-sided document transport mode, first, the reverse sheet feeding flapper 22 and the reverse flapper 23 are located at the solid line positions in FIG. In this state, the document P1 is guided to the reverse feeding paths (H), (F), and (L) (FIG. 23).
(See (a)).

When the trailing edge of the document passes through the one-way flapper 24, the rollers 17 and 18 are rotated in the reverse direction to transport the document P1 in the reverse direction.

Since the supply / discharge flapper 25 is at the position indicated by the solid line in FIG. 4, the document P1 conveyed in the reverse direction is guided to the conveyance path (d) on the platen 3 (see FIG. 23 (b)).

When the original P1 is further conveyed a predetermined distance from the time when the rear end of the original in the conveying direction is detected by the reversing sensor 50, the wide belt 7 stops. In this state, the document P1 is in the reading position R1 in the fixed reading mode.
(See FIG. 24A).

The path switching solenoid 107 is turned off around the time when document placement is completed. Thereby, the reversing sheet feeding flapper 22 and the supply / discharge flapper 25 swing to the position indicated by the chain line in FIG. When the scanning of the second side of the document P1 is completed by the scanner unit 204 of the copying machine body 1,
The wide belt 7 rotates in the reverse direction, and the document P1 is conveyed to the document supply / discharge path (e). At this time, the reversing flapper 23 swings simultaneously with the reverse rotation of the wide belt 7, and is in the state of the chain line in FIG. Therefore, the document P1 is guided to the document reversing path (g) (see FIG. 24B).

When the original is conveyed a predetermined distance from the time when the leading edge of the original is detected by the reversing sensor 50, the rotation of the wide belt 7 temporarily stops and then changes from reverse rotation to normal rotation. When the leading end of the inverted document approaches the transport path (d) on the platen, the transport speed of the second feeding roller 9 and the transport speed of the wide belt 7 are controlled so as to match.

When the trailing edge of the preceding document P1 passes through the nip point of the second feeding roller 9, the second feeding roller 9 stops and waits for the arrival of the following document.

The preceding document P1 is independently conveyed by the wide belt. However, when the document P1 is conveyed by a predetermined distance from the time when the trailing edge of the document P1 is detected by the paper feed sensor 35, the wide belt 7 stops. As a result, the document P1 is placed at the stop position R1 in the fixed reading mode.

Further, before and after the trailing edge of the preceding document is detected by the paper feed sensor 35, the separating operation of the succeeding document P2 is started, and the well-known skew feeding is performed by the stopped second feeding roller 9. . After that, the reversing feed path (H), (F),
The document P2 is guided to (i) (see FIG. 25A).

During the scanning of the first side by the scanner unit 204 of the copying machine body 1, the reversing operation of the succeeding document P2 is completed in the same manner as the preceding document P1. The subsequent original P1 after the reversal is
The vicinity of the leading end is on standby while being nipped by the first reversing roller 17 (see FIG. 25B). At this time, the distance between the preceding original P1 and the following succeeding original P2 is L14.
It is controlled to become.

When the scanning for reading the first side of the preceding original P1 is completed, the first reversing roller 17 and the second reversing roller 1
8 is started simultaneously with the forward rotation of the wide belt 7. Thereby, as shown in FIG. 26, when the succeeding document P2 is placed on the platen 3, the rear end of the preceding document P1 passes through the nip of the manual registration roller 11,
The value of L14 described above is determined. Thereafter, the same operation is continued up to the final document Pn.

[Manual Document Transport Mode] FIGS. 27 and 28 are diagrams showing the flow of a document when a manual document is transported.
When the manual document detection sensor 60 detects that the document P1 is set (see FIG. 27A), the manual flapper 27 and the manual shutter 28 move to the solid line positions in FIG. Then, the document P1 is conveyed by the manual feed roller 13 and skewed by the stopped manual registration roller 11. Thereafter, when the leading edge of the document arrives at the reading position R1 of the platen 3, the document P1 is read.
Is stopped (see FIG. 27B). At this time, the manual flapper 27 and the manual shutter 28 return to the positions indicated by the dashed lines in FIG. 3 to enable the next original set.

After the scanning by the scanner 204 of the copier body 1 is completed, the original P1 is rotated by the reverse rotation of the wide belt 7.
Is discharged toward the discharge roller 12. Discharge roller 1
2 rotates, the manual feed roller 13 also rotates. However, since the leading edge of the document P2 is regulated by the manual shutter 28, the manual feed roller 13 slips and the document P2 does not advance (FIG. 28A).
reference).

The trailing end of the document P1 is the manual registration sensor 3
4, the manual registration roller 11 stops (see FIG. 28B), and the manual flapper 27 and the manual shutter 28 move to the positions indicated by the solid lines in FIG.

Thereafter, the original P2 is conveyed by the manual paper feed roller 13 to the manual registration roller 11, and after the skew feeding is completed, the original P2 is placed on the platen 3 in the same manner as the original P1.

[Control Device] FIG. 29 is a block diagram showing a circuit configuration of the control device. The control device is mainly composed of a microprocessor (CPU) 501,
Drive circuits of various loads and sensor signals are connected to the input / output port 01.

The control device includes a RAM that is backed up by a battery (not shown) and a ROM that stores control sequence software. An IC 502 is a communication IC for controlling data communication with the copying machine main body 1. The copier body 1 is provided with a display panel 49.

In the figure, a separation motor 100 (DC brush motor) includes a driver 503 and a controller 503.
a is controlled by the controller 503a.
, A reference clock serving as a reference for the motor rotation speed, an on / off signal, and the like are input from the CPU 501.

Transport motor 101 (stepping motor)
Are driven by a stepping motor driver 504. Similarly, the belt motor 102 (stepping motor) is driven by the stepping motor driver 505 at a constant current. Each driver receives a phase excitation signal and a motor current control signal from the CPU 501.

Swing motor 103 (stepping motor)
Is driven by a driver 506 at a constant voltage, and the discharge motor 104 (DC brush motor) is driven and controlled by a driver 507 and a controller 504a for FG servo.

The motors 100 to 104 are provided with encoders 100a to 104a and detectors 100b to 104b, respectively, as means for detecting the rotational speeds of these motors (see FIG. 3).

Further, the stopper solenoid 105 is driven by the driver 508, and the separation clutch 106 is similarly driven by the driver 509 and the path switching solenoid 10.
7 is a driver 510; a reversing flapper solenoid 108 is a driver 511;
12 respectively.

The drivers 503 to 512 are all
The operation is controlled by a signal connected to the input / output port 01. Further, the separation sensor 30,
Skew detection sensor 31, mixed loading detection sensor 32, reversal detection sensor 33, manual feed registration sensor 34, paper feed sensor 3
5, reversing sensor 50, manual document detection sensor 60, registration sensor 39, document set detection sensor 40, document trailing edge detection sensor 41, final document detection sensor 43, paper width detection sensor 44, paper feed roller home sensor 45, swing position Various sensors such as the sensor 46 are connected to the input port of the CPU 501, and are used to monitor the behavior of the document and the behavior of the movable load in the apparatus.

[Copying Operation] FIG. 30 is a flowchart showing a reading processing procedure in the copying operation in the control device.
This processing is stored in a ROM (not shown) in the control device, and is executed by the CPU 501.

The document set detection sensor 40 detects whether a document is set on the document tray 4 and determines whether a copy key (not shown) on the operation unit of the copying machine is pressed. (Step S1).

When a document is set on the document tray 4 and the copy key is pressed, it is determined whether or not the copy mode transmitted from the apparatus body is the one-sided document mode (step S2). If the mode is the one-sided document mode, it is determined whether or not the document trailing edge detection sensor 41 has failed (step S3). If the document trailing edge detection sensor 41 has not failed, it is determined whether or not the document trailing edge detection sensor 41 is off (step S4). When the document trailing edge detection sensor 41 is off, the copying process is performed in the first moving reading mode (step S5), and a series of processes is ended. On the other hand, when the trailing edge detection sensor 41 is out of order, or when the trailing edge sensor 41 is turned on in step S4, the copying process is performed in the second non-stop reading mode (step S6), and a series of processes is performed. finish. As described above, when the document trailing edge detection sensor 41 is out of order, the sensor output is always set to the ON state. Reading is performed at the reading position R3 of the large size sheet.

On the other hand, if the mode is not the one-sided original mode in step S2, the copying process is performed in the two-sided original mode (two-sided original mode, step S7), and the series of processes is terminated. On the other hand, if the original is not set on the original tray 4 or the copy key (not shown) is not pressed in step S1, it is determined whether or not the manual original is set by the manual original detection sensor 60; It is determined whether the copy key has been pressed (step S8). If no manual document is set or the copy key is not pressed, the process returns to step S1. On the other hand, when the manual document is set and the copy key is pressed, the copying process is performed in the manual mode (step S9).
A series of processing ends.

[First Flow Reading Mode] FIG. 31 is a flowchart showing the processing procedure of the first flow reading mode in step S5. A pickup DOWN process is performed to move the paper feed roller 5 onto the paper placed on the document tray 4 (step S21).
Separation processing (step S22) and sheet feeding processing (step S23) are performed to separate only the sheets.

The optical system of the copying machine main body (scanner unit 2
04) is started at a predetermined position (reading position R1), and a document flow reading process for reading a document image is started (step S24). Thereafter, the process waits until the separation sensor 30 detects the trailing end of the document (step S25), and the separation sensor 30 detects a break in the document bundle to determine whether the document is the final document (step S26). .

If the document is not the final document, the document is
The paper discharge process is started to discharge the paper to the upper side (step S2).
8) Return to the process of step S22. Step S
If it is determined in step S26 that the document is the last document, a sheet discharging process is performed (step S27), and then a pickup UP process is performed to return the sheet feeding roller 5 to the upper limit position (step S2).
9), a series of processing ends.

When the length of the document in the feeding direction is L ′ mm, the scanner unit 204 is connected to the second feeding roller 9.
, L'mm or more, and located downstream in the transport direction in the transport path (R2, R3 in FIG. 12). The position control of the scanner unit 204 may be performed by a known stepping motor control or by a mechanical stopper.

[Second Flow Reading Mode] FIG. 32 is a flowchart showing a processing procedure of the second flow reading mode in step S6. First, the paper feed roller 5 is moved to the document tray 4.
Pickup DOW to move on the paper placed on
N processing is performed (step S31). Thereafter, a separation process is performed to separate the uppermost document by one sheet (step S3).
2) and a paper feeding process (step S33) is performed.

Further, while the optical system (scanner unit 204) of the copying machine body is fixed at a predetermined position (reading position R3), a document flow reading process for reading a document image is started (step S34). Since the fixing position is near the paper discharge unit, the paper discharge process is started to discharge the document onto the paper discharge tray 10 (step S35).

Thereafter, the process waits for the separation sensor 30 to detect the trailing end of the document (step S36), and the document set sensor 40 detects a break in the document bundle to determine whether the document is the final document. (Step S37). If it is not the final document, the process returns to step S32 and the same process is repeated.

On the other hand, if it is the last document, the pickup UP process is performed to return the sheet feeding roller 5 to the upper limit position (step S38), and a series of processes is ended.

In the second drift reading mode, as described above,
The scanner unit 204 of the copying machine main body 1 is at the reading position R3 shown in FIG.

[Single-Sided Original Fixed Reading Mode] FIG. 33 is a flowchart showing a processing procedure in the single-sided original fixed reading mode. This process is not executed in the process shown in FIG. First, a pickup DOWN process is performed to move the paper feed roller 5 onto the paper placed on the document tray 4 (step S41), and then a separation process is performed to separate only the topmost document (step S42). Then, a paper feeding process (step S43) is performed.

When the uppermost document comes into contact with the platen and is placed on the left end on the platen, an optical system moving document that reads the document image while moving the optical system (scanner unit 204) of the copier body. A reading process is performed (step S44). While the reading process is being performed, the document set detection sensor 40 detects the break of the document bundle and determines whether the document is the final document (step S45).

If the document is not the final document, the document is
The paper discharge process is started to discharge the paper to zero (step S4).
6) Returning to the processing of step S42, the same processing is repeated. On the other hand, if it is the last document, the paper discharge process is performed (step S47), and then the pickup UP process is performed to return the paper feed roller 5 to the upper limit position (step S4).
8), a series of processing ends.

[Duplex Document Mode] FIG. 34 is a flow chart of step S7.
6 is a flowchart showing a processing procedure in a double-sided original mode in FIG. Pickup DOWN processing is performed to move the paper feed roller 5 onto the paper placed on the document tray 4 (step S51), and then separation processing (step S52) is performed to separate only the topmost document by one sheet. Do. Further, a pre-reversal process (step S53) is performed so that the separated document is turned upside down so that the second surface of the document comes into contact with the platen and is placed on the left end on the platen.

Thereafter, an optical system moving document reading process for reading a document image while moving the optical system (4 between the scanner units 20) of the copying machine body is performed (step S5).
4). When the reading is completed, the reversing process is performed again for reversing the front and back surfaces (step S55), the optical system moving document reading process is performed (step S56), and the reading of the document image on the first surface is also completed.

While the reading process is being performed, the document set sensor 40 detects the break of the document bundle and determines whether or not the document is the final document (step S57). If the document is not the final document, the paper discharge process is started to discharge the document to the paper discharge tray 10 (step S58), and the process returns to step S52 to repeat the same process.

On the other hand, if it is the last original in step S57, the paper discharge processing is performed (step S59), and then the pickup UP processing is performed to return the paper feed roller 5 to the upper limit position (step S60), and a series of The process ends.

[Manual Insertion Mode] FIG. 35 is a flowchart showing the processing procedure in the manual insertion mode. A manual sheet feeding process is performed to convey the document set in the manual sheet feeding unit onto the platen 3 of the copying machine body (step S61). Thereafter, an optical system moving document reading process for reading a document image while moving the optical system (scanner unit 204) of the copying machine body is performed (step S62).

When the reading process is completed, the paper discharge process is started to discharge the document to the paper discharge tray 10 (step S63), and thereafter, it waits until the trailing edge of the document is detected by the manual feed registration sensor 34 (step S63). In step S64, the presence or absence of the next document is detected by the manual document detection sensor 60 (step S65).

If there is a next original, the process returns to step S61 and the same process is repeated. On the other hand, if there is no next original, a manual paper ejection process is performed (step S66), and a series of processes is ended.

[Pickup DOWN Processing] FIG. 36 is a flowchart showing the pickup DOWN processing procedure in steps S21, S31, S41 and S51. The swing motor 103 is driven to lower the paper feed roller 5 from the position shown in FIG. 4 where the paper feed roller home sensor 45 is turned on to the original bundle P placed on the original tray 4 (step S71). The lifting arm 51 and the swing arms 53 and 57 are lowered.

After the feed roller home sensor 45 is turned off to confirm that the feed roller 5 has been lowered (step S72), the first swing position sensor 46 and the second swing position sensor 47 are turned on. When it is detected that the paper feed roller 5 has dropped onto the paper surface (step S73), the swing motor 103 is turned off to stop its drive (step S7).
4).

[Pickup UP Processing] FIG. 37 is a flowchart showing the pickup UP processing procedure in steps S29, S38, S48 and S60.

The rocking motor 103 is driven to raise the paper feed roller 5 to the position shown in FIG. 4 (step S8).
1). When it is detected that the paper feed roller home sensor 45 has been turned on to reach the upper limit position (step S82),
The swing motor 103 is turned off and its driving is stopped (step S83). At this time, the rotation direction of the swing motor 103 is opposite to that during the pickup DOWN processing.

[Separation Processing] FIG. 38 shows steps S22 and S22.
It is a flowchart which shows the separation processing procedure in S32, S42, and S52. First, the separation motor 100 is turned on (step S91), and the paper feed roller, the separation belt 6, the separation / conveyance roller 8, and the first feeding roller 16 that are falling on the document bundle P are rotated, respectively, so that the document bundle is The uppermost document on P is separated by one sheet and conveyed in the sheet path (a).

Thereafter, when the separation sensor 30 is turned on to detect the leading edge of the original (step S92), the second separation process is completed within a predetermined time range.
The speed of the separation motor 100 is controlled based on the remaining transport distance until the leading edge of the document is abutted against the feed roller 9 to form a loop and the elapsed time until the separation sensor 30 is turned on (step S93).

Thereafter, when the leading edge of the original is detected by turning on the paper feed sensor 35 (step S94), a separation loop counter which starts counting by a clock signal input from the separation clock is started (step S95), and the set count ends. Thereafter (step S96), the separation motor 100 is turned off (step S97), and the process ends.

Thereafter, the leading end of the document abuts the nip portion of the second feed roller 9 and stops with a predetermined amount of loop formed. Thus, even when skew occurs during separation, the skew is corrected.

[Sheet Feeding Processing] FIG. 39 shows steps S23 and S23.
It is a flowchart which shows the paper feed processing procedure in 33 and S43. Normally, as shown by the solid line in FIG. 4, when the path switching solenoid 107 is in the OFF state, the reverse sheet feeding flapper 22 is biased so that the document is conveyed to the sheet path (H). The switching solenoid 107 is turned on to switch the reverse sheet feeding flapper 22 to the position indicated by the chain line in FIG. 4 (step S101).

[0210] The front end is abutted against the second feeding roller 9, and
The separation motor 100, the conveyance motor 101, and the belt motor 102 are turned on to convey the document nipped by the first feed roller 16 to the sheet paths (c) and (d) (step S102). Feed roller 16, second
The feeding roller 9 and the wide belt 7 are driven.

At the same time, a size check counter for counting by a clock signal input from the inverted clock is started (step S103). Then, by detecting the leading edge of the document by the registration sensor 39, it is confirmed that the document has been conveyed to the sheet path (C) (step S1).
04).

Thereafter, when it is detected that the rear end of the document has passed the separation sensor 30 (step S105), a separation off counter which counts by a clock signal input from the separation clock is started (step S10).
6).

When the counting for the distance from the first feed roller 16 to the separation sensor 30 is completed (step S107), the rear end of the original has fallen out of the first feed roller 16 and the separation motor 100 Is turned off to stop driving the first feed roller 16 (step S10).
8).

Thereafter, when the paper feed sensor 35 detects that the rear end of the document has passed (step S109), the size check counter is stopped (step S110), and the size check processing is performed based on the data (step S1).
Perform 12).

At the same time, a registration counter counted by the belt excitation clock is started to stop the original at a predetermined position on the platen 3 (step S112). Thereafter, at the time when the distance L4 from the paper feed sensor 35 to the second feeding roller 9 has been counted (step S113), the transport motor 101 is turned off (step S114), and when the started registration counter ends (step S114). (Step S115), the belt motor 102 is turned off (step S116). Then, the path switching solenoid 107 is turned off (step S
117).

[Pre-Reversal Processing] FIG. 40 shows a step S53.
9 is a flowchart showing a pre-inversion processing procedure in FIG. As shown by the solid line in FIG.
Since the bus switching solenoid 107 is turned off and the original is urged so that the original is conveyed to the sheet path (h), the leading end is abutted against the second feeding roller 9 and the first feeding roller 16 The separation motor 100 and the conveyance motor 101 are turned on in order to convey the nipped document to the sheet path (h) (step S121), and the first feeding roller 16, the second feeding roller 9, and the first reversing roller are turned on. The roller 17 and the second reversing roller 18 are driven.

At the same time, a size check counter counting by a clock signal input from the inverted clock is started (step S122). Then, by detecting the leading edge of the document by the registration sensor 39, it is confirmed that the document has been conveyed to the sheet path (h) (step S1).
23). Thereafter, when it is detected that the trailing edge of the document has passed the separation sensor 30 (step S124), a separation off counter that counts by a clock signal input from the separation clock is started (step S125).

When the counting for the distance from the first feed roller 16 to the separation sensor 30 is completed (step S126), the trailing end of the document has fallen out of the first feed roller 16, so that the separation motor 100 Is turned off to stop driving the first feed roller 16 (step S12).
7).

Thereafter, when it is detected that the rear end of the original has passed the paper feed sensor 35 (step S128), the size check counter is stopped (step S129), and the size check processing is performed based on the data (step S1).
Perform 30).

When it is detected that the trailing end of the document has passed through the registration sensor 39 (step S131), the trailing edge of the document is counted by the reverse magnetic excitation clock so as to stop at a predetermined position passing through the sheet path (h). The pre-reversal counter is started (step S132).

At this time, the reverse flapper 23 is urged so that the original is conveyed to the sheet path (re) as shown by the solid line in FIG. When the started pre-reversal counter ends (step S133), the transport motor 10
1 is turned off (step S134).

After the motor is turned off for a predetermined time, the conveying motor 101 is reversed, the belt motor 102 is turned on (step S135), the original is conveyed to the sheet path (e), and the leading end of the original has passed the reversing sensor 36. Is detected (step S136), it is confirmed that the sheet has been conveyed to the sheet path (e). Further, when it is detected that the rear end of the document has passed the reversing sensor 36 (step S137), the transport motor 101 is turned off (step S13).
8) The pre-feed counter is counted by the belt excitation clock to stop the original at a predetermined position on the platen (step S139). When the started pre-feed counter ends (step S14).
0), the belt motor 102 is turned off (step S1).
41).

[Reversal Processing] FIG. 41 is a flowchart showing the procedure of the reversal processing in step S55. As shown by the solid line in FIG. 4, the reversing flapper 23 is urged so that the original is conveyed to the sheet path (re) when the reversing flapper solenoid 108 is off.
The reverse flapper solenoid 108 is turned on, and the reverse flapper 23 is switched to the position shown by the solid line in FIG.

Further, the path switching flapper solenoid 107 is turned on so that the reverse sheet feeding flapper 22 and the supply / discharge flapper 25 are respectively switched to the positions indicated by the chain lines in FIG. 4 (step S151). The belt motor 10 is used to convey the original on the platen 3 to the sheet path (e).
2. Turn on the transport motor 101 (step S15
2) The wide belt 7, the second feeding roller 9, the first reversing roller 17, and the second reversing roller 18 are driven. Reversing sensor 3
6 is detected (step S).
153) When the leading edge of the document reaches a predetermined position in the sheet paths (f) and (g), the inversion counter counted by the belt excitation clock is started to stop / reverse the belt motor 102 (step S15).
4).

When the started reversal counter ends (step S155), the belt motor 102 is turned off (step S156), and after the motor is turned off for a predetermined time, the belt motor 102 is reversed (step S15).
7). During this time, since the conveyance motor 101 is on, the first reversing roller 17, the second reversing roller 18, and the second feeding roller 9 where the document is nipped are driven, so that the sheet path (f), (f) G).

By detecting that the leading edge of the original has passed through the paper feed sensor 35 (step S158), it is confirmed that the original has been conveyed to the sheet path (g), and the trailing edge of the original has passed the registration sensor 39. Then (Step S15
9), turning off the transport motor 101 (step S16)
0). At the same time, a reverse sheet feeding counter counted by the belt excitation clock is started to stop the document at a predetermined position on the platen (step S16).
1).

When the reversing sheet feeding counter which has started is completed (step S162), the belt motor 102 is turned off (step S163), the reversing flapper solenoid 108 is turned off, and the reversing flapper 23 is moved to the position shown by the solid line in FIG. Further, the path switching solenoid 107 is turned off, and the reversing sheet supply flapper 22 and the supply / discharge flapper 25 are returned to the positions shown by the solid lines in FIG. 4 (step S164), and the process ends.

In step S157, the document is pulled in the opposite direction by the first reversing roller 17 and the wide belt 7, but since the nip force of the first reversing roller 17 is stronger, the document follows the reversing roller. Conveyed. However, in the case of a document long in the feeding direction, the document is greatly affected by the nip force between the pressing roller inside the wide belt 7 and the platen, so that the document does not follow the first reversing roller 17. As a result, the timing at which the belt motor 102 is stopped and reversely rotated, that is, the value of the reversal counter is set to a value such that the control differs depending on the length of the document in the feeding direction.

[Sheet Discharge Processing] FIG. 42 shows steps S27 and S27.
It is a flowchart which shows the paper discharge processing procedure in 28 and S35. When the discharge flapper solenoid 109 is turned off, the discharge flapper 26 is urged to a position where the tip of the flapper is lower than the platen as shown by a chain line in FIG. (D),
The belt motor 102 and the paper discharge motor 104 are turned on (step S171), and the wide belt 7, the manual paper feed roller 13 and the paper discharge roller 12 are driven in order to carry the paper (D).

By detecting that the leading edge of the document has passed through the manual feed registration sensor 37 (step S172), it is confirmed that the document is being conveyed to the sheet path (nu).
When the trailing edge of the document has passed the manual feed registration sensor 37 (step S173), the belt motor 102 is turned off (step S174).

At the same time, a paper discharge counter for counting by a clock signal input from the paper discharge clock is started (step S175), and after the set count is completed (step S176), the paper discharge motor 104 is turned off (step S176). In step S177, the document passes through the sheet path (N), passes through the discharge roller 12, and is discharged onto the discharge tray 10.

[Manual Paper Feeding Process] FIG.
3 is a flowchart showing a manual paper feed processing procedure in FIG. In a state where the paper discharge flapper solenoid 109 is off, the paper discharge flapper 26 and the manual feed shutter 28 are urged to a position where the tip of the paper discharge flapper is lower than the platen as shown by the chain line position in FIG. Manual flapper 2
Reference numeral 6 denotes a state in which the leading end of the document set in the manual paper feed unit is abutted. Therefore, the paper discharge flapper solenoid 109 is turned on, and the manual shutter 28 and the paper discharge flapper 26 are switched to the position shown by the solid line in FIG. 3 (step S181).

Then, the paper discharge motor 104 is turned on (step S182), and the original is conveyed into the sheet path by rotating the manual paper feed roller 13. Thereafter, when the leading edge of the document is detected by turning on the manual feed registration sensor 34 (step S183), a manual feed loop counter counted by a clock signal input from the paper ejection clock is started (step S18).
4).

After the end of the set count (step S1)
85) By turning off the paper discharge motor 104 (step S186), the leading edge of the document is abutted against the nip portion of the manual registration roller 11, and the operation is stopped with a predetermined amount of loop formed. Thereby, the manual paper feed roller 13
Even if skewing occurs during conveyance in the, it can be corrected.

Then, after turning off the motor for a predetermined time,
The paper discharge motor 104 and the belt motor 102 are turned on in order to convey the document to the sheet paths (D) and (D) (step S187), and the manual paper feed roller 13, the manual paper registration roller 11, and the wide belt 7 are driven. At the same time, a size check counter for counting by a clock signal input from the belt clock is started. (Step S188).

Further, a belt registration counter counted by the excitation clock to stop at a predetermined position on the platen 3 is started (step S189).
When the manual feed registration sensor 34 is turned off to detect that the rear end of the document has passed (step S190),
The size check counter is stopped, and a size check process (step S191) is performed based on the data.

At the same time, since the trailing end of the original has passed through the manual feed roller 13, the discharge motor 104 is turned off (step S192). Thereafter, when the started manual feed registration counter ends (step S19).
3) Turn off the belt motor 102 (step S1)
94). Then, the paper discharge flapper solenoid 109 is turned off (step S195), and the process ends.

[Original Flow Reading Process] FIG. 44 is a flow chart showing the flow of original flow reading process. The belt motor 102 is turned on (step S201) and the wide belt 7 is driven so that the image of the document is read by the fixed optical system of the copying machine main body. At the same time, when the leading edge of the document reaches a predetermined position, an image-on-counter, which is counted by the belt excitation clock, is turned on to turn on the image-origin signal (step S202).

At this time, the belt motor speed is controlled to a constant speed by outputting an excitation clock signal based on the moving reading speed data (V) received from the copying machine main body. Thereafter, when the started image on-counter ends (step S203), the image signal is turned on and transmitted to the copying machine body (step S204).

After receiving the image tip signal, the copier body calculates the time required for the leading edge of the document to reach the optical system fixed position during the flow reading, and actually reads the image. The image signal is turned off after a predetermined time has elapsed (steps S205, S206, S207). Thereafter, when the rear end of the document has passed the reading position, the belt motor 1
02 is turned off (step S208).

The moving reading speed data (V) may be equal to the reading speed (V1) when the optical system is moved.
May be different. In particular, when V> V1, the reading of the document image is completed in a shorter time than the normal optical system moving reading, so that the use of such a document transport device improves the copying speed.

[Size Check Processing] FIG. 45 is a flowchart showing the size check processing procedure in step S191. In this size check process, the document size is determined 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 as a document size determining means to obtain the true document size (length in the feed direction). (Step S211). At this time, the document is being conveyed by the second feed roller 35 and the wide belt 7, and the feed amount and the count value by the belt excitation clock surely match. Thereafter, according to the corrected size data, A5, B5, A4, B5R, A4R, B4,
A3 size determination is performed (steps S212 to S22).
4).

In the above embodiment, the case where the present invention is applied to a copying machine as an image forming apparatus has been described. However, the present invention is not limited to this.

The present invention is also applicable to a reading device in which a reader unit and a document feeder are integrated.
Further, it is possible to adopt a configuration in which the copying machine main body has a document conveying device.

Further, in the above-described embodiment, the case has been described in which when the document trailing edge detection sensor 41 for detecting the trailing edge position of the document fails, the reading is performed at the large sheet size reading position R3. When the reading position is changed using the document width detection sensor 44 that detects the length in the sheet conveyance direction, the same reading operation is performed even when the document width detection sensor fails. Is also good.

In the above-described embodiment, when the document trailing edge detection sensor 41 fails, the sensor output is always in the ON state, that is, in the paper present state. Therefore, even if step S3 in FIG. In step S4, the mode shifts to the second scanning mode, and the reading position R3 of the large-size sheet is set.
Was to be read. Therefore,
If the document trailing edge detection sensor has failed, the process of step S3 only needs to know that the sensor output has failed, and it is possible to cope with a failure that does not always turn on.

[0247]

According to the first aspect of the present invention, there is provided a sheet conveying apparatus for conveying a sheet from which an image is read by an image reading apparatus to an image reading position. Means, detecting means for detecting the length of the placed sheet in the transport direction, and transport means for transporting the sheet to the image reading position according to the length of the detected sheet in the transport direction. When the detecting means fails, the conveying means conveys the sheet to an image reading position corresponding to a sheet of a predetermined size, so that the sensor for detecting the length of the sheet in the conveying direction has failed. In this case, the reading operation can be continued without stopping the apparatus.

According to the sheet conveying apparatus of the present invention, the image reading position corresponding to the sheet of the predetermined size is the image reading position corresponding to the sheet of the maximum size. Even in this case, all the images recorded on the sheet can be read.

According to the image reading apparatus of the third aspect,
Detecting means detects the length of the sheet conveyed to the image reading position in the conveying direction, setting means sets the image reading position in accordance with the detected length of the sheet in the conveying direction, and reading means sets the image reading position. When reading an image recorded on the sheet at the set image reading position, the setting unit sets the image reading position according to a sheet of a predetermined size when the detection unit fails,
If the sensor for detecting the length of the sheet in the transport direction has failed, the reading operation can be continued without stopping the apparatus. For example, if the document trailing edge sensor installed on the tray fails for some reason,
By fixing the sensor output to the state with paper,
The reading operation can be continued without stopping the apparatus by performing the reading at the reading position of the large size sheet regardless of the document size. The same effect can be obtained in the image reading method according to the seventh aspect.

According to the image reading apparatus of the fourth aspect,
Since the image reading position set according to the sheet of the predetermined size is an image reading position corresponding to the sheet of the maximum size, all the images recorded on the sheet can be read even if the sensor fails.

According to the image reading apparatus of the fifth aspect,
A sheet conveying unit that separates sheets one by one from the sheet bundle placed on the tray and conveys the sheets to the image reading position, wherein the reading unit converts an image recorded on the sheet conveyed to the image reading position Since the reading is performed in a fixed state, the reading can be continued without stopping the so-called sink reading operation even when the sensor fails.

According to the image reading apparatus of the sixth aspect,
Since the present invention is applied to the image forming apparatus, the efficiency of image formation can be increased without stopping the image forming apparatus.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a copying machine.

FIG. 2 is a diagram showing a configuration of a printer unit 300.

FIG. 3 is a diagram illustrating a configuration of a document feeder 2;

FIG. 4 is a diagram illustrating a position of a flapper provided in a conveyance path.

FIG. 5 is a diagram illustrating a sheet feeding / separation mechanism.

FIG. 6 illustrates a swing arm 53, a sheet feeding roller 5, and a lifting arm 5.
It is a figure which shows members, such as 1.

FIG. 7 is a plan view showing a paper feed / separation mechanism.

FIG. 8 is a diagram illustrating an operation of a sheet feeding / separating mechanism.

FIG. 9 is a diagram illustrating an operation of a sheet feeding / separation mechanism.

FIG. 10 is a diagram illustrating an operation of a sheet feeding / separation mechanism.

FIG. 11 is a diagram illustrating a configuration of a document feeding path.

FIG. 12 is a diagram showing a document reading position on a platen 3;

FIG. 13 is a diagram illustrating a reading position of a document.

FIG. 14 is a diagram illustrating a flow of a document in a single-side fixed reading mode.

FIG. 15 is a diagram illustrating a flow of a document in a single-sided document transport mode.

FIG. 16 is a diagram illustrating a flow of a document in a one-sided document transport mode.

FIG. 17 is a diagram illustrating a flow of a document in a large-size one-sided document conveyance mode.

FIG. 18 is a diagram illustrating a flow of a document in a large-size one-sided document conveyance mode.

FIG. 19 is a diagram illustrating a flow of a document when a double-sided document is conveyed.

FIG. 20 is a diagram illustrating a flow of a document when a double-sided document is conveyed.

FIG. 21 is a diagram illustrating a flow of a document when a two-sided document is conveyed.

FIG. 22 is a diagram illustrating a flow of a document when a two-sided document is conveyed.

FIG. 23 is a diagram illustrating a flow of a document when a large-size double-sided document is conveyed.

FIG. 24 is a diagram illustrating the flow of a document when a large-size double-sided document is conveyed.

FIG. 25 is a diagram illustrating a flow of a document when a large-size double-sided document is conveyed.

FIG. 26 is a diagram illustrating the flow of a document when a large-size double-sided document is conveyed.

FIG. 27 is a diagram illustrating a flow of a document when a manual document is conveyed.

FIG. 28 is a diagram illustrating a flow of a document when a manual document is conveyed.

FIG. 29 is a block diagram illustrating a circuit configuration of a control device.

FIG. 30 is a flowchart showing a reading processing procedure during a copying operation.

FIG. 31 is a flowchart showing a processing procedure in a first moving-reading mode in step S5.

FIG. 32 is a flowchart showing a processing procedure in a second moving-reading mode in step S6.

FIG. 33 is a flowchart showing a processing procedure in a one-sided original fixed reading mode.

FIG. 34 is a flowchart showing a processing procedure in a duplex document mode in step S7.

FIG. 35 is a flowchart illustrating a processing procedure in a manual feed mode.

FIG. 36 shows steps S21, S31, S41 and S5.
3 is a flowchart showing a pickup DOWN processing procedure in No. 1;

FIG. 37 shows steps S29, S38, S48 and S6.
7 is a flowchart showing a pickup UP processing procedure at 0.

FIG. 38 shows steps S22, S32, S42 and S5.
6 is a flowchart illustrating a separation processing procedure in the second embodiment.

FIG. 39 is a flowchart showing a sheet feeding processing procedure in steps S23, S33 and S43.

FIG. 40 is a flowchart showing a pre-inversion processing procedure in step S53.

FIG. 41 is a flowchart showing the inversion processing procedure in step S55.

FIG. 42 is a flowchart showing a paper discharge processing procedure in steps S27, S28 and S35.

FIG. 43 is a flowchart showing a manual paper feed processing procedure in step S61.

FIG. 44 is a flow chart showing a procedure of a document flow reading process.

FIG. 45 is a flowchart showing the size check processing procedure in step S191.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Copier main body 2 Document feeder (ADF) 4 Document tray 41 Document trailing edge detection sensor 501 CPU

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Katsuya Yamazaki 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2H076 AA04 BA63 BA71 BB04 EA21 3F048 AA02 AB02 BA07 BB03 CA03 CC04 EB23 3F343 FA03 FB02 LC04 MB15 5C062 AA05 AB17 AB30 AB32 AC11 AC58 AC66 AC67 AC68 AC71 AE15 BA00 5C072 AA01 BA13 EA04 NA01 NA04 NA07 RA01 RA03 RA04 WA02 XA01

Claims (7)

[Claims] 1. A sheet conveying device for conveying a sheet from which an image is read by an image reading device to an image reading position, comprising: a mounting means for mounting the sheet; and a length of the mounted sheet in the conveying direction. Detecting means for detecting, and conveying means for conveying the sheet to the image reading position corresponding to the length of the detected sheet in the conveying direction, wherein the conveying means has a predetermined function when the detecting means fails. A sheet conveying device for conveying the sheet to an image reading position corresponding to a sheet of a size. 2. The sheet conveying device according to claim 1, wherein the image reading position corresponding to the predetermined size sheet is an image reading position corresponding to a maximum size sheet. 3. A detecting means for detecting a length of a sheet conveyed to an image reading position in a conveying direction, and a setting means for setting the image reading position according to the detected length of the sheet in the conveying direction. Reading means for reading an image recorded on the sheet at the set image reading position, wherein the setting means sets the image reading position according to a sheet of a predetermined size when the detection means has failed. An image reading apparatus, comprising: 4. The image reading apparatus according to claim 3, wherein the image reading position set according to the predetermined size sheet is an image reading position corresponding to a maximum size sheet. 5. A sheet conveying means for separating sheets one by one from a sheet bundle placed on a tray and conveying the separated sheets to the image reading position, wherein the reading means applies a sheet to the sheet conveyed to the image reading position. The image reading device according to claim 3, wherein the recorded image is read in a fixed state. 6. An image reading apparatus according to claim 3, wherein said apparatus is applied to an image forming apparatus. 7. A sensor detects a length of the sheet conveyed to the image reading position in the conveying direction, and sets the image reading position according to the detected length of the sheet in the conveying direction. When reading an image recorded on the sheet at the read image reading position, if the sensor fails, the image reading position is set according to a sheet of a predetermined size.