JP2591491B2 - Automatic document feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder attached to an image processing apparatus such as a copying machine and an image reader, and more particularly to a document feed control mechanism.

[0002]

2. Description of the Related Art In recent years, an automatic document feeder (hereinafter, referred to as an ADF) has been proposed in order to shorten the time required to replace a document among the times required for copying and to save the troublesome work of document replacement. ) Have been developed and put into practical use. If this type of ADF is a measure to reduce indirect costs (time and labor) related to copying, a direct cost (consumables such as copying paper and toner) can be reduced directly by copying two originals onto both sides of one copying paper. Or double-sided copying
There is a method of reducing and copying two originals to one side of a copy sheet of the size of one original (two-sided original single-sided copying). In the former two-sided copying, only one copy sheet is required, but two toner sheets are required. On the other hand, the latter two-sided single-sided copying is economical because only one copy sheet and one toner are required. further,
When both are combined, four originals can be copied on both sides of one copy sheet, which is extremely economical.

[0003] By the way, conventionally provided various ADFs
Is to transport documents one by one onto a platen glass (platen). To perform two-sided single-sided copying, the operator must arrange the documents on the platen glass one by one.
Hassle and time haven't improved at all. As a remedy, a two-sheet feed mode, in which two originals are fed in parallel in the transport direction on the platen glass and the two originals are simultaneously exposed and then discharged from the platen glass, can be executed. Such ADFs are disclosed in, for example, JP-A-62-89943 and JP-A-60-2942.

Japanese Patent Application Laid-Open No. Sho 62-89943 discloses that the two-sheet feed mode is performed by an ADF provided with one endless belt. However, this A
The DF has a problem when discharging the original. That is, since the two originals are arranged side by side without any gap, if the two originals are discharged from the platen glass as they are, the leading end of the second original will push the rear end of the first original, There is a possibility that alignment or page alignment on the discharge tray may be disturbed.

Japanese Patent Application Laid-Open No. Sho 60-2942 discloses that the ADF having two transport belts performs the two-document feed mode, and further shifts the drive timing of the two transport belts when discharging the original. It is disclosed that two documents are spaced apart from each other so as not to disturb the alignment on the discharge tray. However, in this ADF, since two transport belts are used, a shadow is formed at a boundary portion of the transport belt,
There is a fatal problem that this shadow appears on the copy image when copied.

That is, when executing the two-sheet original feed mode, taking the above-mentioned prior art into consideration,
Japanese Patent Application Laid-Open No. Sho.
As described in Japanese Patent Application Laid-Open No. 2-89943, the one-belt system is superior in that no shadow appears in a copied image. However, the control for keeping the space between the two originals at the time of discharging the original has not been solved. For example, the following can be considered as a solution. The stopper is inserted between the two documents at the timing of driving the transport belt when the documents are discharged, and the discharge of the second document is temporarily stopped to provide an interval.
However, this necessitates the addition of a stopper and its driving mechanism, which also increases the cost.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a two-document feed mode in a single-belt mode in which the shadow of a transport belt does not appear on a copy image, and a simple configuration and control of the document. An object of the present invention is to provide an automatic document feeder capable of keeping a space between two documents at the time of discharging.

In order to achieve the above object, the present invention is directed to a two-sheet document which is stretched over a first position on a platen and a second position adjacent to the first position in the document transport direction. And a document transport belt for discharging the document from the platen after the end of the exposure operation, and a tray for receiving the document discharged from the platen by the document transport belt. In an automatic document feeder provided with a discharge unit for discharging the document, the first document is transferred to the discharge unit by driving the document conveyance belt, and then the driving of the document conveyance belt is temporarily stopped.
Thereafter, the driving of the document conveying belt is restarted, and the second document is delivered to the discharging means.

[0009]

In the present invention, when a document is discharged, 1
The driving of the document transport belt is temporarily stopped after the first document has been delivered to the discharging unit, so that a gap is provided between the first document and the second document, and then the driving of the document transport belt is stopped. By restarting, the second document is delivered to the discharge unit. Therefore, the two originals are ejected at an interval from the platen, and the leading end of the second original does not push the rear end of the first original, and the alignment or page alignment on the output tray is disturbed. Is reliably prevented.

That is, the present invention employs a one-sheet belt system in which no shadow appears in the copy image to execute the two-sheet document feed mode, and the document is conveyed from the document transport belt to the discharge means when the document is discharged. The transfer of the original is controlled by turning on and off the drive of the original conveyance belt, so that there is no need for a stopper or other members, and a simple configuration, and a simple on / off control allows a gap between two originals. Was opened.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an automatic document feeder (AD) according to the present invention will be described.
The embodiment F) will be described with reference to the accompanying drawings. This A
The DF is installed on the upper surface of the copying machine main body 1.
An outline of the copying machine will be described.

(Schematic Configuration and Operation of Copying Machine) In FIG. 1, a copying machine main body 1 is installed on a re-feeding path box 60, a sheet feeding section on the left side, and a duplex / composite unit 70 on the right side.
And a sorter 90. At substantially the center of the copying machine main body 1, a photosensitive drum 10 is installed so as to be rotatable at a constant peripheral speed V in the direction of arrow a. Around the photosensitive drum 10, a main eraser 11, a charging charger 12, a sub eraser 13, and a magnetic brush type developing device 1 are provided.
4, transfer charger 15, sheet separation charger 16,
A blade type cleaning device 17 is sequentially arranged. The photoreceptor drum 10 has a well-known photoreceptor layer provided on the surface thereof. With the rotation in the direction of arrow a, each time copying is performed, the main eraser 11, charging charger 12, and sub-eraser 13 remove and charge the photosensitive drum. , Unnecessary parts are neutralized,
The electrostatic latent image formed on the surface after the image exposure by the optical system 20 is formed into a toner image by the developing device 14.

An optical system 20 is provided so that an original image can be scanned below an original platen glass 19.
It comprises a first mirror 22, a second mirror 23, a third mirror 24, a projection lens 25, and a fourth mirror 26.
The exposure lamp 21 and the first mirror 22 are integrally formed into a block, and the ratio (v / m: m is a copy magnification) of the peripheral speed V of the photosensitive drum 10 (constant regardless of the same magnification / variable magnification). It can move in the direction of arrow b at a speed. The second mirror 23 and the third mirror 24 are integrally blocked, and can move in the direction of the arrow b at a speed of V / 2m. Changing the copy magnification involves an operation of correcting the optical path by moving and swinging the fourth mirror 26 while the lens 25 moves on the optical axis.

The copy paper is accommodated in a fixed automatic paper feed cassette 30 and a detachable automatic paper feed cassette 35 provided on the left side of the copying machine main body 1.
The sheets 1 and 36 are selectively driven to rotate, so that sheets are fed one by one. The upper surface of the cassette 30 is a manual paper feed unit 32 from which copy paper can be fed one by one. The copy paper fed from the cassette 30 and its manual feed unit 32 is transported to a pair of timing rollers 40 through a pair of transport rollers 33, and the copy paper fed from the cassette 35 is directly transported to the timing roller 40, Here, it temporarily waits. The copy paper is sent out to the transfer unit in synchronization with the image formed on the surface of the photosensitive drum 10 by the timing roller 40, and the photosensitive drum 1
The toner image is transferred by the corona discharge of the transfer charger 15 and separated from the photosensitive drum 10 by the AC corona discharge of the separation charger 16 and the stiffness of the sheet itself. Thereafter, the copy paper is supplied to the air suction means 42.
Fixing device 43 while being sucked onto a conveyor belt 41 having
Then, the toner image is fixed and discharged from the pair of discharge rollers 44.

On the other hand, the toner and the electric charge remaining on the surface of the photosensitive drum 10 after the transfer are removed by the cleaning device 17 and the main eraser 11 to prepare for the next copying process.

(Detection of Copy Paper Size) Micro switches SW1 to SW4, SW5, SW6 to SW
9, SW10 is installed. Switches SW1 to SW
4, SW6 to SW9 are turned on and off in accordance with the position of the copy paper width direction regulating plate and the like, and the cassettes 35, 3 are set on the basis of a 4-bit code corresponding to the combination of the on and off.
It detects whether the copy paper is set in the vertical or horizontal direction with respect to the size of the copy paper set to 0 and the paper feed direction.
The size that can be copied in the copying machine, that is, the size of copy paper that can be set in each of the cassettes 30 and 35 is, for example, A
3, A4, A5, A6, B4, B5, B6 and A
4, A5 and B5 can be selected vertically or horizontally. Further, the switches SW1 to SW4 also detect the attachment / detachment of the cassette 35. Table 1 below shows the switch SW1
An example of a code table based on .about.SW4 is shown. This table 1
In FIG. 7, the switch is represented as 0 when the switch is on, and 1 when the switch is off. When all the switches are off, it indicates that the cassette 35 is not mounted on the sheet feeding unit. Note that one set of switches SW6 to SW9 performs similar detection. Microswitches SW5 and SW10 provided in each paper feed unit directly detect the presence or absence of copy paper in cassettes 35 and 30, respectively.

[0017]

[Table 1]

(Structure and paper passing for double-sided / combined copying) The double-sided / combined unit 70 is roughly composed of a first switching claw 71,
The second switching claw 72, the discharge rollers 73 and 74, the transport rollers 75 and 76, each guide plate located around them and constituting a transport path, and a re-feeding device 80 are provided. A sorter 90 provided with 91 is installed.

The sheet re-feeding device 80 has a detachable sheet re-feeding cassette 81, a pickup roller 85 used for both sheet storage and sheet re-feeding, and a storage roller 86 that is driven to rotate in contact with the roller 85. , A paper feed roller 87 and a sabaki roller 88. The refeeding cassette 81 has a bottom plate 82 that can be rotated about a rear end 82a, and the bottom plate 82 can be rotated from a dotted line position to a solid line position by a push-up mechanism (not shown).

The re-feeding path box 60 is composed of a pair of conveying rollers 61, 62, 63 and respective guide plates located around them and forming a sheet path. The sheet sent from the unit 70 is transported by a pair of conveying rollers 61,
The guide plate 4 of the copying machine main body 1
8 and 49, the sheet is conveyed to the timing roller pair 40.

The paper passing mode in the duplex / composite unit 70 includes a discharge mode, a duplex copy mode, and a composite copy mode, and the paper passing mode in each mode is changed by switching the positions of the switching claws 71 and 72. That is, in the discharge mode, the switching claw 71 is set at the position indicated by the dotted line in FIG. 1, and the copy paper is discharged to the sorter bin 91. In the double-sided copying mode, the switching claws 71 and 72 are set at the positions indicated by the solid lines, and the copy paper copied to one side is fed into the re-feeding cassette 81 as described above. In the composite copying mode, the switching claw 72 is set to the position indicated by the dotted line, and the copy paper copied on one side is immediately conveyed to the re-feeding path box 60.

(Structure and Operation of Automatic Document Feeder (ADF)) The ADF 100 generally includes a document feeder 110, a document feeder 120, and a document discharger 130. Can be opened. Therefore,
As shown in FIG. 1, the ADF 100 automatically conveys originals one by one or two continuously in a state where the originals are set on the original platen glass 19 as described below. In addition to setting the document at the upper predetermined position, the operator can lift the document upward and place the document on the platen glass 19 to execute copying. ADF100
Is detected by the switch PSW (see FIG. 10),
The control of the ADF 100 and the control of the copying machine main body 1 are associated with each other by this detection signal.

The document feeder 110 includes a document tray 111
, A pickup roller 112, a forward rotation roller 113 and a reverse rotation roller 114 for document separation,
Feed motor (not shown) for driving 2, 113, 114
And a document detection sensor SE1. The document tray 111 has a slide plate (not shown) for positioning the document in the width direction. The document is set on the document tray 111 with the image side down, and this state is detected by the sensor SE1. The pickup roller 112 is capable of moving up and down, and usually stands by upward. Documents are in document tray 1
When the sensor SE1 is turned on and the ADF start switch SSW (see FIG. 10) is turned on by the operator, the pickup roller 112 descends, comes into pressure contact with the upper surface of the document, and finally rotates. Feed the upper document.

The forward rotation roller 113 can be driven to rotate in the document feeding direction, and the reverse rotation roller 114 can be driven to rotate in the document return direction.
13 and 114 are driven to rotate, and only one upper document is sent to the document transport unit 120 by the rotation of the forward rotation roller 113, and the lower document is returned to the document tray 111 by the rotation of the reverse rotation roller 114.

The document conveying section 120 includes a pinch roller 121,
122 and a drive motor 123 thereof (see FIG. 2), a transport belt 125 and a drive motor thereof (not shown), and document discharge sensors SE2 and SE3. The transport belt 125 is endlessly stretched around support rollers 126a and 126b.
In the state of being in contact with the upper side, it can be driven forward and reverse in the direction of arrow c.

That is, when the sensor SE2 detects the leading edge of the original sent from the original feeder 110, the pickup roller 112 and the forward / reverse rotation roller 1 have a slight time delay.
The rotation of the document 13 and 114 is stopped, and the leading edge of the document comes into contact with the nip portion of the pinch rollers 121 and 122 to form a loop upstream thereof. Thus, the skew of the document is corrected.

Further, originals are pinch rollers 121, 12
2 and the transport belt 125 is forwardly rotated in the direction of the arrow c to be conveyed onto the platen glass 19. The stop of the document is controlled by setting a timer when the trailing edge of the document is detected by the sensor SE2, and stopping the forward rotation of the transport belt 125 when the timer ends. Thus, the document is stopped at a predetermined position on the platen glass 19.

Here, a copying operation start signal is output from the ADF 100 to the copying machine body 1, and the copying operation is started in the copying machine body 1. When the set number of image exposure scans by the optical system 20 are completed, the copy machine body 1 outputs a document exchange signal to the ADF 100. With this signal, the transport belt 125 is driven to rotate forward in the direction of arrow c, and the document is discharged.

By the way, as shown in FIG. 2, the length of the original is measured by a pulse signal from the sensor SE5 based on the rotation of the disk 124 fixed to the support shaft 121a of the pinch roller 121. That is, the output of the sensor SE5 is the logical sum of the sensor SE2 for detecting the passage of the document and the drive output of the pinch roller 121, and the second microcomputer 202
The original length signal is obtained by counting the number of pulses input to the sensor SE2 (see FIG. 10) and passing the sensor SE2.

The width of the original is detected by a sensor SE3.
being classified. This sensor SE3 is, in this embodiment,
Detected (ON) when A4 and B5 documents are fed horizontally, and not detected (OFF) when fed vertically.
It is installed in a position. As a result, the size of A4, A5, B4, B6, etc., which cannot be determined only by the document length signal, and whether the document is vertically or horizontally passed is identified.

The document discharge unit 130 includes discharge rollers 131 and 1
32, 133, and 134, a guide plate around the discharge tray 135, a drive motor (not shown) for each of the rollers 131 to 134, and a document detection sensor SE4.

When the image exposure scanning for the number of copies by the optical system 20 is completed and a document exchange signal is output from the copying machine main body 1, the transport belt 125 is driven to rotate forward, and
The rollers 131 to 134 are driven to rotate, and the document is discharged from the platen glass 19 to the discharge tray 135.
The document discharging operation is stopped after a predetermined time from the document trailing edge detection signal of the sensor SE4, that is, when the document is stored on the discharge tray 135. When a document trailing edge detection signal from the sensor SE4 is issued, the presence or absence of a document on the document tray 111 is determined by the signal from the sensor SE1, and if a document is set, the above-described document feeding and stopping are performed. And each operation of discharging is repeated.

(Operation in Document Two-Sheet Feed Mode) In this embodiment, the ADF 100 sets a document one by one at a predetermined position on the platen glass 19 and discharges the image after exposing and scanning. In addition, two originals are successively fed onto the original platen glass 19 and set in a predetermined position in series, and the two originals are image-exposed at once, and discharged after the exposure scan is completed. The feed mode can be selected.

(Document Feeding Operation) The document feeding operation when the two-sheet feed mode is selected will be described below with reference to FIGS. 3, 4, and 5. FIG. When the two-sheet feed mode is selected and the ADF start switch SSW is turned on, the originals stacked on the original tray 111 are fed from the uppermost original D1 by the rotation of the pickup roller 112, and rotated forward and backward as described above. The sheet is separated by the rollers 113 and 114 and sent out from the feeding section 110 (see FIG. 3A). The leading end of the first document D1 sent out in this way contacts the nip portion between the pinch rollers 121 and 122, and forms a loop upstream thereof (see FIG. 3B). Hereinafter, this process is referred to as a leading edge resist process.

Next, the original is conveyed onto the original platen glass 19 by rotating the pinch rollers 121 and 122 and rotating the conveyor belt 125 forward in the direction of arrow c (see FIG. 3C). ). Thereafter, when the rear end of the document D1 passes the pinch rollers 121 and 122, the rotation of the pinch rollers 121 and 122 and the conveyance belt 125 is stopped (see FIG. 4D).

Next, the transport belt 125 is driven to rotate in the reverse direction in the direction of arrow c ', and the rear end of the original D1 is pinched by the pinch rollers 121,1.
22 is stopped in a state of contact with the nip portion of FIG.
(E)). Hereinafter, this processing is referred to as a rear end resist processing. While the first document D1 remains in the trailing edge registration process, the second document D2 is sent out from the document tray 111 (see FIG. 4F), and the leading edge registration process is performed (FIG. 5 (g)). )reference). With this, two originals D1 and D
2 are continuously arranged side by side with the rear end and the front end registered by the pinch rollers 121 and 122.

In this state, the pinch rollers 121, 122
Then, the transport belt 125 is driven to rotate forward, and the originals D1 and D2 are simultaneously transported onto the original platen glass 19 (see FIG. 5H). When the rear end of the second document D2 reaches a predetermined position on the platen glass 19, that is, the exposure start position by the optical system 20, the pinch rollers 121 and 122 and the transport belt 125
Is stopped (see FIG. 5 (i)). As a result, the two originals D1 and D2 are set at predetermined positions on the original platen glass 19 in a state where they are continuously arranged in series in the transport direction.

(Original Discharge Operation) In the above-described two-sheet feed mode, two originals are arranged side by side without any gap. Since the rear end of the document is pushed, alignment or page alignment on the discharge tray 135 may be disturbed.

In the two-sheet feed mode,
Sheets of the document are discharged onto the discharge tray 135 at intervals,
The arrangement of the documents on the discharge tray 135 is ensured. That is, the first document is discharged by the discharge rollers 131 and 132.
, The forward rotation of the conveyor belt 125 is stopped, and
This is a method in which the first document is made to stand by on the document table glass 19, an appropriate space is provided between the two, and then the transport belt 125 is rotated forward again.

More specifically, the transport belt 125 is driven to rotate forward by a document exchange signal, and the discharge rollers 131 to 13 are driven.
4 is rotated (see FIG. 6A). As a result, the originals D1 and D2 begin to be discharged in the direction of arrow c, and when the leading end of the first original D1 is detected by the sensor SE4, the normal rotation of the transport belt 125 is stopped (FIG. 6B). reference). From this state, the first document D1 continues to be the discharge roller 1
The documents D2 are conveyed at 31 to 134, and the second document D2 is on standby on the platen glass 19, with a space between them (see FIGS. 6C and 7D). The first original D1
Is detected by the sensor SE4, the transport belt 1
25 is driven forward again (see FIG. 7E), and the two originals D1 and D2 are discharged onto the discharge tray 135 at appropriate intervals.

(Single-sheet feed when double-sheet feed mode is selected) By the way, when the above-described two-sheet feed mode is selected, if the total number of original documents is an odd number, the originals are fed in pairs. As a result, there is finally only one document. Accordingly, one final document is fed and the sensor S
When a document empty signal is output at E1, processing in the single-sheet feed mode is executed for the final document.

(Automatic Optimal Magnification Setting Function (AMS)) Next, in this copying machine, when the copy paper size and the original size are designated by the operator, the original image is cut off to the copy paper of the selected size. It has an automatic optimal magnification setting function (hereinafter, referred to as AMS) for automatically setting an optimal copying magnification formed without occurrence.

When this AMS mode is selected, the second C
The document size is determined and coded by the PU 202 and the first
Sent to CPU 201. The first CPU 201 stores the document size code and the cassette 30 selected by the operator.
The optimum copy magnification is calculated from the copy paper size code set in 35, and if the calculated copy magnification is within the specifications of the copying machine, the copy magnification is set. On the other hand, if it is out of the specification, the operator is warned that it is impossible to set the optimum copy magnification, and is prompted to set the copy magnification manually.

Table 2 below shows the relationship between the original size and the copy paper size in the AMS mode in the normal copy mode in which the originals are conveyed one by one, and the copy magnification calculated and set by them.

[0045]

[Table 2]

(Automatic optimum copy paper size setting function (AP
S)) In this copying machine, when an original size and a copy magnification are designated by an operator, a paper cassette in which a copy paper of a size that can form an original image without image cut is automatically set. Has an automatic optimum copy paper size setting function (hereinafter referred to as APS).

When this APS mode is selected, the second C
The document size is determined and coded by the PU 202 and the first
Sent to CPU 201. The first CPU 201 calculates the optimum copy paper size from the document size code and the copy magnification selected by the operator, and feeds the copy paper of the calculated size, ie, the cassette 30, 35.
Select On the other hand, if the copy paper of the calculated size is not set in any of the cassettes 30 and 35, or if the copy paper has a specification other than that of the copying machine, the operator is warned that there is no copy paper of the optimum size. Prompts the user to manually select the paper feed unit or manually set the copy magnification.

Table 3 below shows the relationship between the document size and the copy magnification in the APS mode in the normal copy mode in which the documents are conveyed one by one, and the copy paper size calculated and set by them.

[0049]

[Table 3]

(Relationship Between Document, Magnification, and Copy Paper in Double Sheet Feed Mode) When the ADF 100 is operated in the double sheet feed mode,
When copying two original images on one side of a single copy sheet,
The document size, copy magnification, and copy paper size have the following relationship. For example, if two A4 transverse documents are conveyed, and the copy magnification is 1.000 times, A3 is selected as the copy paper, so that two A4 transverse original images are overlaid on the A3 copy paper. Fits without shortage. If the copy magnification is 0.707, the original image fits in just enough by selecting A4 portrait paper as copy paper. On the other hand, when A3 copy paper is selected for two A4 landscape documents, the copy magnification is set to 1.00.
If it is set to 0x, or if A4 vertical copy paper is selected, and if the copy magnification is set to 0.707x, the A4 horizontal copy of the original image is printed on one copy paper in the same manner as described above. Can be paid without excess or shortage.

Therefore, by performing copying in the two-sheet feed mode using the ADF 100, two original images can be formed on one copy sheet, thereby saving copy sheets and copy time. Connect. Also, if the two-sided copy mode is used, four original images can be formed on the front and back surfaces of one copy sheet. Further, if the copier body 1 is provided with a book dividing function, that is, a function of exposing and scanning an image of a book original one by one, the two-sheet feed mode, the book dividing function mode, and the double-sided copying mode are used together. One document can be imaged on each of the front and back surfaces of one copy sheet. These copying modes further save copying paper and copying time.

(Operation Panel) In FIG. 8, the operation panel 150 of the copying machine main body 1 is provided with keys, display means, and the like described below. Various keys are provided with switches inside and are turned on when pressed.

Reference numeral 151 denotes a print key for starting a copying operation. Numeral 152 is used to enter the number of copies and the like. Reference numeral 153 denotes a clear / stop key having a role of a stop key for canceling multi-copy in the middle and a role of clearing the number. Reference numeral 154 denotes an interrupt key for executing an interrupt copy. Reference numeral 155 denotes a copy mode switching key for switching the copy mode between normal copy, double-sided copy, and composite copy. Reference numeral 156 denotes a magnification selection key for setting a copy magnification to a preset magnification or an arbitrary magnification. A copy paper selection key 157 is used to select a copy paper size. Reference numeral 158 denotes a document size detection mode selection key for selecting one of the AMS, APS, and manual modes. Reference numeral 159 denotes a feed mode selection key for selecting the feed mode of the original between one-sheet feed and two-sheet feed.

The operation panel 150 further has display means described below. Reference numeral 160 denotes a four-digit display segment for displaying the number of copies and the like. Reference numeral 161 denotes a 4-digit display segment for displaying a manually set copy magnification. 162
165 are LEDs for displaying preset copy magnification. 166 is a normal copy, 167 is a duplex copy, 1
68 is an LED for displaying the composite copy. 169 is an LED for displaying a copy paper size. 170 is an AMS mode, 171 is an APS mode, and 172 is a manual mode LED. 173 is a single-sheet feed mode,
Reference numeral 174 denotes an LED that indicates a two-sheet feed mode. These various LEDs rotate each time the corresponding keys 155 to 159 are turned on once.

(Control Circuit) FIG. 9 shows an input / output configuration of the first CPU 201 for controlling the copying machine body 1, and FIG.
4 shows an input / output configuration of a second CPU 202 that controls F100. The CPUs 201 and 202 are connected to each other for synchronization.

The input / output ports of the first CPU 201 have various key switches 151 to 15 on the operation panel 150.
9. Micro switches SW1 to SW installed in the paper feeding unit
A switch matrix 203 including 10 and the like is connected, and a display segment 160 and a matrix 204 including display LEDs are connected via the switch matrix 203 and a decoder 205. The output port outputs on / off signals to a main motor, a developing motor, and the like in the copying machine body 1. The terminal B1 receives a pulse signal of the main motor.

The input port of the second CPU 202 has an ADF
100 open / close detection switch PSW, ADF start switch SSW, sensors SE1 to SE for detecting document conveyance
4. A sensor SE5 for detecting the rotation of the pinch roller motor 123 is connected. The output port includes a pickup roller 112, a feed motor for driving the forward / reverse rotation rollers 113 and 114, a transport motor for driving the transport belt 125,
A solenoid for moving the pickup roller 112 up and down,
A discharge motor or the like for driving the discharge rollers 131 to 134 is connected. A pulse signal of the transport motor is input to the terminal B2.

A clock terminal SCK for data sampling and output of the first CPU 201 and an interrupt output terminal PC
O, data output terminal SOUT and data input terminal SIN
Are connected to the clock input terminal SCK, the interrupt input terminal INT, the data input terminal SIN, and the data output terminal SOUT of the second CPU 202.

(Control Procedure) The control procedure of this embodiment will be described below in detail with reference to FIGS. FIG. 11 shows a main routine of the first CPU 201 for controlling the copying machine body 1. When the first CPU 201 is reset and the program is started, first, in step S1, the internal RAM is cleared, various registers and the like are initialized, and initialization for setting each device to the initial mode is performed.

Here, the flags used in the following routine will be described in advance. Copy flag F0: Indicates that the copying machine is operating, and is set to "1" from the time when the copy start processing is completed to the time when the copy processing is completed. Mode flag F1: indicates a document feed mode in the ADF 100, and is set by the feed mode selection key 159. When "0", it indicates a one-sheet feed mode, and "1"
2 shows a two-sheet feed mode.

Feed flag F2: This flag indicates the number of documents actually fed on the platen glass 19 by the ADF 100. When "0", it indicates that the number is one, and "1".
Indicates that the number is two. Even when the two-sheet feed mode is selected, if the total number of originals is an odd number, it is "0" at the time of transporting the final original. Note that this flag F2 is set by a feed number signal from the second CPU 202.

Returning to the routine, in step S2, the first C
The main timer of the PU 201 is set. This main timer determines the time required for one of the main routines, and its value is set in advance in step S1. Next, the subroutines shown in steps S3 to S5 are sequentially called. Step S3 is a subroutine of a key input process.
Copy paper size set in 0, 35 to internal RAM
, A copy mode setting process using the copy mode switching key 155, and a magnification setting process using the magnification selection key 156. Step S4 is a subroutine of a document feed mode switching process.
9 for setting the document feed mode of the ADF 100. Step S5 is a copy start processing subroutine for starting the copy operation.

Next, in step S6, it is determined whether or not the copy flag F0 is "1". If the copy flag F0 has been reset to "0", the process proceeds to step S8, and if it has been set to "1", the process proceeds to step S7. A subroutine of a copying process for performing an actual copying operation is executed, and the process proceeds to step S8. Step S8
Then, data transmission and reception with the second CPU 202 are processed. The signals communicated in this step S8 include:
Signals transmitted from the first CPU 201 to the second CPU 202 include a copying operation signal, a document feed mode signal, and a document replacement signal when image exposure scanning for a set number of sheets is completed.

The signals transmitted from the second CPU 202 to the first CPU 201 include the following. ADF mode signal: a signal that is set to "1" when a document is loaded on the document tray 111 during the copying operation and when the ADF 100 is not operating, and is reset to "0" when the last document is discharged.

Set complete signal: Original is platen glass 19
A signal that is output when the sheet is conveyed and stopped at the upper predetermined position. Document size signal: ADF100 sensors SE3 and SE5
The code signal of the original size detected at. Feed number signal: a signal indicating the number of originals actually fed onto the original platen glass 19. Prohibition signal: A signal output when the fed document size is inconvenient for copying.

When the processing in each of the above subroutines is completed, the flow returns to step S2 after waiting for the end of the counting of the main timer in step S9. Various timers appearing in each subroutine are counted using the length of time of this one routine. That is, various timers determine the end of counting based on how many times this one routine is repeated.

FIG. 12 shows a subroutine of a document feed mode switching process executed in step S4 of the main routine. First, in step S10, it is determined whether or not the copy flag F0 is "0", and if it is set to "1",
That is, if a copying operation is being performed, the process returns to the main routine.
If it has been reset to "0", it is determined in step S11 whether the feed mode selection switch 159 is on-edge. If it is not on edge, the process returns to the main routine. If it is on edge, it is determined in step S12 whether or not the mode flag F1 is "0". If the mode flag F1 has been reset to "0", that is, if the single-sheet feed mode has been set at this point, it is determined in step S13 whether or not portrait paper has been selected as copy paper. If it is horizontal, the process returns to the main routine. If it is vertical, step S
In step 14, the mode flag F1 is set to "1", that is, the two-sheet feed mode is set. In the two-sheet feed mode, the original image becomes longer in the vertical direction (image scanning direction), which is inconvenient for horizontally passing copy paper. Therefore, the two-sheet feed mode is accepted only when the vertically copying paper is selected.

On the other hand, if it is determined in step S12 that the mode flag F1 is set to "1", the mode flag F1 is reset to "0" in step S15, that is, the single-sheet feed mode is set.

FIG. 13 shows a subroutine of the copy start process executed in step S5 of the main routine. First, in step S20, it is determined whether or not the ADF mode signal is "1", and if it is set to "1",
If copying using 100 has been selected (see step S123), it is determined in step S21 whether a document inhibit signal has not been output. If the document inhibit signal has not been output, it is determined in step S22 whether or not the set completion signal has been output. If the set completion signal has not been output, the process stands by. If output is completed, that is, if the document is set at a predetermined position on the platen glass 19 (see steps S170 and S212), copying is performed in step S25. The flag F0 is set to "1".

On the other hand, if it is determined in step S21 that the document prohibition signal has been output (see step S206), a prohibition display is output in step S26 to prohibit the start of the copying operation. If it is determined in step S20 that the ADF mode signal has been reset to "0", it is confirmed in step S23 that the copy flag F0 has been reset to "0", and the print switch 151 is reset in step S24. It is determined whether it is an on-edge. And
When the print switch 151 is turned on, the copy flag F0 is set to "1" in step S25.

When the copy flag F0 is set to "1" as described above, the copying process in step S8 is started. It should be noted that the control of the copying process is well known, and a description thereof will be omitted.

FIG. 14 shows the second CP for controlling the ADF 100.
7 shows a main routine of U202. When the second CPU 202 is reset and the program starts, first, in step S100, the internal RAM is cleared, various registers and the like are initialized, and initial settings for setting each device to the initial mode are performed.

Here, the flags used in the following routine will be described in advance. Copy flag F0, mode flag F1, feed flag F
2: The above flags are the same as those used in the control of the first CPU 201. ADF operation flag F3: indicates that the ADF 100 is operating, and is set to "1" from the start of document feeding until the last document is discharged.

ADF feed flag F4: This flag indicates that the ADF 100 is feeding a document, and is set to "1" from the start of document feeding until the stop at a predetermined position on the document glass 19 is completed. Is set to Leading edge registration flag F5: Indicates that the leading edge registration process for sending the original from the tray 111 to the leading edge registration position is being performed, and is from the start of feeding the first and second originals to the completion of the leading edge registration process. It is set to "1" during the period.

The leading edge registration start flag F6 is for indicating the timing for starting the leading edge registration processing, and is "1" from the start of feeding the first and second originals until the feeding motor and the pickup roller 112 rise. Is set to Standby flag F7: Indicates that the document is waiting at the leading edge registration position, and is set to "1" from the completion of the leading edge registration process to the restart of feeding onto the document table glass 19.

Set complete flag F8: Document tray 111
Is set at a predetermined position on the platen glass 19, and is set to "1" from the completion of feeding to the start of discharging. Discharge flag F9: This flag indicates that the document is being discharged from the platen glass 19 to the discharge tray 135, and is "1" from the generation of the document exchange signal to the completion of discharge.
Is set to Document flag F10: This flag indicates whether the document in the feeding state in the two-sheet feeding mode is the first sheet or the second sheet. When "0", it indicates the first sheet. Sometimes it is the second sheet.

Returning to the routine, in step S101, the main timer of the second CPU 202 is set. This main timer determines the time required for one of the main routines, and the value is set in advance in step S100.

Next, it is determined in step S102 whether or not the ADF mode is set. If NO, the process proceeds to step S112, and if YES, the subroutines of steps S103 to S105 are sequentially called. Step S103
Executes a process of detecting the ON edge of the ADF start switch SSW and starting the operation of the ADF 100. In step S104, a leading edge registration process for sending the document from the document tray 111 to the leading edge registration positions of the pinch rollers 121 and 122 is executed. In step S105, a process of detecting the size of the document sent from the document tray 111 is performed.

Next, in step S106, the mode flag F
It is determined whether 1 is "1". If the mode flag F1 has been reset to "0", that is, if the single-sheet feed mode, the subroutines of steps S107 and S110 are called, and the process proceeds to step S112. Step S1
Reference numeral 07 denotes a process for feeding and setting a normal original one by one on the original platen glass 19. A step S110 executes a process of discharging one document to the discharge tray 135.

At step S106, the mode flag F1
Is set to “1”, that is, 2
If the sheet feed mode has been selected, a process of feeding and setting the documents on the platen glass 19 two by two in a subroutine of step S108 is executed. Then, step S10
In step S9, it is determined whether or not the feed flag F2 is "1". If the flag is set to "1", a process of discharging two documents to the discharge tray 135 is executed in a subroutine of step S111. Transition. If the feed flag F2 has been reset to "0", the subroutine of the step S110 is executed, and the process proceeds to the step S112.

In step S112, transmission and reception of data with the first CPU 201 are processed. The signals communicated here are the same as those described in the processing in step S8. When the processing in each of the above subroutines is completed, the process returns to step S101 after waiting for the end of the counting of the main timer in step S113. Various timers appearing in each subroutine are counted using the length of time of this one routine.

FIG. 15 shows a subroutine of ADF start processing executed in step S103 of the main routine of the second CPU 202. First, in step S120, the copy flag F0 is reset to "0", in step S121, the ADF operation flag F3 is reset to "0", and in step S122, the sensor SE1 on the document tray 111 is reset. It is determined whether or not the document is on, and if any is NO, the process immediately returns to the main routine. If both are YES, that is, the copying operation or the ADF operation is not being performed, and the document is set on the tray 111, If it is confirmed that the ADF mode signal is present, the ADF mode signal is set to "1" in step S123.

Next, in step S124, the process waits for the ON edge of the ADF start switch SSW, and then proceeds to step S12.
In step S5, the ADF operation flag F3 is set to "1", the ADF feed flag F4 is set to "1" in step S126, and the leading edge registration flag F5 and the leading edge registration start flag F6 are set to "1" in step S127. . Subsequently, in step S128, it is determined whether or not the mode flag F1 is "1".
In step 129, the feed flag F2 is set to "1", and if it has been reset to "0", the feed flag F2 is set in step S130.
2 is reset to "0", and this subroutine ends.

FIG. 16 shows a subroutine of the leading edge registration process executed in step S104 of the main routine of the second CPU 202. First, in step S140, it is determined whether or not the leading edge registration flag F5 is "1". If the flag is reset to "0", the process immediately returns to the main routine.
If it is set to "1", it is determined in step S141 whether or not the leading edge registration start flag F6 is "1".
If the flag F6 has been reset to "0", the process proceeds to step S144, and if it has been set to "1", the feed motor and the pickup solenoid are turned on in step S142. As a result, the pickup roller 112 is pressed against the uppermost surface of the document and rotates, and the forward / reverse rotation roller 11 is rotated.
3 and 114 also start rotating, and only one uppermost document is sent out from the tray 111 (see FIG. 3A). Subsequently, in step S143, the leading edge registration start flag F
6 is reset to "0", and the routine goes to Step S144.

In step S144, it is determined whether or not the sensor SE2 is on-edge. If the sensor SE2 is not on-edge, the process proceeds to step S146.
In step S146, the leading edge registration timer is set.
Move to The leading edge registration timer detects that the leading edge of the document detected by the sensor SE2 is a pinch roller 121,1.
The time is set until the loop is formed by contacting the nip portion 22. Therefore, in step S146, after waiting for the end of the count of the leading end registration timer, the process proceeds to step S146
In step 147, the feed motor and the pickup solenoid are turned off. In step S148, the leading end registration flag F5 is reset to "0". In step S149, the standby flag F is reset.
7 is set to "1", and this subroutine ends.
As a result, the leading edge of the document sent out from the tray 111 abuts on the nip portion of the pinch rollers 121 and 122 to correct the skew, and waits in a state where a loop is formed upstream of the skew (see FIG. 3B). ).

FIG. 17 shows a subroutine of the document size detection process executed in step S105 of the main routine of the second CPU 202. This subroutine is executed while the original is fed from the leading edge registration position to a predetermined position on the original table glass 19, and the sensor SE5 detects the length of the original in the transport direction by the pulse count by the sensor SE5, and detects the width direction. The document size is determined based on the combination of ON and OFF of SE3.

Here, it is first determined in step S150 whether or not the pinch roller motor 123 has started.
This pinch roller motor 123 performs the following step S16
It is turned on at 4. If not rising, step S15
The process proceeds to step S2, and if it is rising, the pulse count of the sensor SE5 is started in step S151, and the process proceeds to step S152. In step S152, the sensor SE2
Is detected, the pulse count of the sensor SE5 is stopped in step S153, and
At 154, the document size is calculated based on the pulse count number and the ON / OFF signal of the sensor SE3. At step S155, a document size signal is output, and this subroutine ends.

FIG. 18 shows a subroutine of the original feeding process in the single-sheet feeding mode executed in step S107 of the main routine of the second CPU 202. First, it is determined in step S160 whether or not the ADF feed flag F4 is "1". If the flag is reset to "0", the process immediately returns to the main routine. If the flag is set to "1",
When the start switch SSW is turned on, step S1
At 61, it is determined whether or not the standby flag F7 is "1". If the standby flag F7 has been reset to "0", step S
166, if it is set to "1", that is,
If the leading edge of the document is registered by the pinch rollers 121 and 122, it is determined in step S162 whether or not the discharge flag F9 is "0". The discharge flag F9 is already "1"
If it is set to, the process proceeds to step S164,
If it has been reset to "0", the conveyance motor is turned on in step S163, the pinch roller motor 123 is turned on in step S164, and the standby flag F7 is turned on in step S165.
Is reset to "0", and the routine goes to Step S166.
As a result, the original is moved from the leading edge registration position to the original table glass 1.
Feeding is resumed on 9.

In step S166, it is determined whether or not the sensor SE2 has an off-edge. If the sensor SE2 is not an off-edge, the process proceeds to step S168.
At step 7, the stop timer is set, and the routine goes to step S168. This stop timer is set to the time from when the rear end of the document passes through the sensor SE2 to when the document reaches the exposure start position on the document table glass 19. Therefore, step S16
In step S8, the process waits for the end of the count of the stop timer, and
In step S169, the pinch roller motor 123 and the conveyance motor are turned off.
U201, and the set completion flag F8 is set to "1" in step S171. Thus, the document is fed to a predetermined position on the platen glass 19 and stopped.

Next, in step S172, it is determined whether or not the sensor SE1 is on. If the sensor SE1 is on, that is, if the next original is on the tray 111, the original is subjected to the leading edge registration processing in advance. In step S173, the leading end registration flag F5 is set to "1", in step S174, the leading end registration start flag F6 is set to "1", and in step S175, the ADF feed flag F4 is reset to "0". To end. If the sensor SE1 is turned off in step S172, that is, if there is no document on the tray 111, step S17
In step 5, the ADF feed flag F4 is reset to "0", and this subroutine ends.

FIGS. 19 to 22 show a subroutine of the original feeding process in the two-sheet feeding mode executed in step S108 of the main routine of the second CPU 202. In this subroutine, only when the size of the first original and the size of the second original are both the same and horizontal (for example, A4 horizontal or B5 horizontal), two-sheet feeding is performed. The process is executed, and when other originals are fed, the copying operation is prohibited and the originals are ejected.

First, in step S180, it is determined whether or not the ADF feed flag F4 is "1". If the flag is reset to "0", the process returns to the main routine immediately. If the flag is set to "1", that is, When the ADF start switch SSW is turned on, it is determined in step S181 whether or not the document flag F10 is "0". If the document flag F10 is set to "1", that is, if the document to be fed is 2
If it is the first sheet, the process proceeds to step S201, and if it is reset to "0", that is, if the original to be fed is
If it is the first sheet, it is determined in step S182 whether or not the standby flag F7 is “1”. If the standby flag F7 has been reset to "0", the process shifts to step S187 to "1".
, That is, if the leading edge registration process for the first document has been completed, it is determined in step S183 whether the discharge flag F9 is “0”. If the discharge flag F9 is set to "1", the process proceeds to step S185 because one set of documents is already being discharged and the conveyance motor is turned on. If the discharge flag F9 is reset to "0", the process proceeds to step S184. The conveyance motor is turned on, the pinch roller motor 123 is turned on in step S185, the standby flag F7 is reset to "0" in step S186, and the flow shifts to step S187. As a result, feeding of the first document from the leading edge registration position onto the document table glass 19 is resumed (see FIG. 3C).

In step S187, it is determined whether or not the sensor SE2 is off-edge. If the sensor SE2 is not off-edge, the flow shifts to step S193; if it is off-edge, step S18 is performed.
In step 8, it is determined whether the document size is horizontal. If the document is in portrait orientation, the original image cannot fit on the copy paper, so a prohibition signal is output to the first CPU 201 in step S206, the ADF feed flag F4 is reset to “0” in step S207, and the discharge flag is set in step S208. F9 is set to "1" to instruct document ejection, and the process returns to the main routine. If the document size is horizontal, it is determined in step S189 whether or not the sensor SE1 is on. If the first document is the final document,
In order to process the document as the first document, the document flag F10 is set to “1” in step S190, and the process proceeds to step S191.
Resets the feed flag F2 to "0" at step S2
Move to 09.

If the sensor SE1 is turned on in step S189, that is, if the second document is on the tray 111, the switchback timer is set in step S192. The switchback timer starts the pinch roller 12 after the trailing edge of the first document is detected by the sensor SE2.
The time is set to completely pass through the nip portion of 1,122.

Next, in step S193, it is determined whether or not the count of the switchback timer has ended. If not, the process proceeds to step S198.
In step 4, the transport motor and the pinch roller motor 123 are turned off (see FIG. 4D). Subsequently, in step S195, the reverse rotation of the transport motor is turned on. As a result, the first document is fed backward to the pinch rollers 121 and 122. And
In step S196, the leading edge registration flag F5 and the leading edge registration start flag F6 are set to "1", and the leading edge registration processing for the second document is prepared. at the same time,
In step S197, the reverse rotation timer is set, and in step S197
Move to 198. This reverse rotation timer is set to the time from when the document is reversely fed to when the trailing edge contacts the nip portion of the pinch rollers 121 and 122 and the trailing edge is registered.

Therefore, after the count of the reverse rotation timer is completed in step S198, the reverse rotation of the transport motor is turned off in step S199, and in step S200, the document flag F10 is set to "1" in order to process the second document thereafter. I do. As a result, the first document has a pinch roller 12 at the rear end.
The nip portions 1 and 122 are brought into contact with each other and stand by in a registered state.

Next, at step S201, the standby flag F7
Is "1". Here, it is determined whether the leading edge registration processing of the second document has been completed, and if the standby flag F7 has been reset to “0”, the process proceeds to step S204.
If it is set to "1", that is, if the leading edge registration processing for the second document has been completed by executing the subroutine of step S104 (see step S149), the conveyance is performed in step S202. The motor and the pinch roller motor 123 are turned on, and the standby flag F7 is reset to “0” in step S203, and the process proceeds to step S2
Move to 04. As a result, the first and second originals are continuously fed onto the original platen glass 19 (FIG. 5).
(G) and (h)).

In step S204, it is determined whether or not the sensor SE2 is off-edge. If it is not off-edge, the process proceeds to step S210. If it is off-edge, that is, when the rear end of the second document has passed the sensor SE2. In step S205, it is determined whether the size of the second document is the same as the size of the first document. If the size is not the same, it is inappropriate for copying.
The CPU 201 outputs the output to the CPU 201, resets the ADF feed flag F4 to "0" in step S207, sets the discharge flag F9 to "1" in step S208, instructs document discharge, and returns to the main routine. If the first and second documents are the same size, a stop timer is set in step S209, and the process proceeds to step S210. This stop timer is the same as that set in step S167.
Then, after waiting for the end of the counting of the stop timer in step S210, the conveyance motor and the pinch roller motor 123 are turned off in step S211 and a document setting completion signal is output to the first CPU 201 in step S212.
In step 213, the setting completion flag F8 is set to "1", and in step S214, the document flag F10 is reset to "0". As a result, the two originals are fed to a predetermined position on the original platen glass 19 side by side in the transport direction and stopped (see FIG. 5 (i)).

Next, in step S215, it is determined whether or not the sensor SE1 is ON. If the sensor SE1 is ON, that is, if the next original is on the tray 111, the original is set as the first original in advance. Step S2 for performing the resist process
In step S16, the leading end registration flag F5 and the leading end registration start flag F6 are set to "1".
The DF feed flag F4 is reset to "0", and this subroutine ends. If the sensor SE1 is off, that is, if there are no more documents on the tray 111, the ADF feed flag F4 is reset to "0" in step S217, and this subroutine ends.

FIG. 23 and FIG. 24 show a subroutine of a one-sheet feed original discharging process executed in step S110 of the main routine of the second CPU 202. This process is executed when the single-sheet feed mode is selected, when the last sheet of the odd-numbered sheet is fed even when the two-sheet feed mode is selected, or when the first sheet is fed. Is determined to be inappropriate for copying in the two-sheet feed mode (NO in step S188).

First, at step S220, the discharge flag F9
Is "1". The discharge flag F9 is set to "1" when the image exposure scanning for the number of copies of the original in the copying machine main body 1 is completed and the original exchange signal is output. Therefore, if the discharge flag F9 remains reset to "0", the process immediately returns to the main routine. If the discharge flag F9 is set to "1", it is determined in step S221 whether the set completion flag F8 is "1". Set completion flag F8
If is set to "0", the process proceeds to step S224. If set to "1", the transport motor and the discharge motor are turned on in step S222, and the set completion flag F8 is reset to "0" in step S223. Then, control proceeds to a step S224. As a result, the document set on the document table glass 19 is started to be discharged.

In step S224, it is determined whether or not the sensor SE4 is off-edge, that is, whether or not the trailing edge of the document has passed the sensor SE4.
226, and if it is off-edge, step S225
To set the discharge timer, and shift to step S226. The discharge timer is set to a time from when the trailing end of the document is detected by the sensor SE4 to when the discharge end reaches the discharge rollers 133 and 134. Therefore, the discharge motor is turned off in step S227 after the counting of the discharge timer is completed in step S226. The document is now in the output tray 13
5 has been discharged.

Next, at step S228, the standby flag F7
Is determined to be "0", that is, whether or not the next original is waiting at the leading edge registration position. If the standby flag F7 is set to "1", the ADF feeding flag F4 is set to "1" in step S232 to execute the feeding process.
And the process moves to step S233. If the standby flag F7 has been reset to "0", that is, if the original discharged at this time is the final original, step S229 is performed.
To turn off the transport motor, reset the ADF operation flag F3 to "0" in step S230, reset the ADF mode signal to "0" in step S231, and
01, and the process moves to step S233.

In step S233, the discharge flag F9 is reset to "0", and in step S234, it is determined whether or not the mode flag F1 is "1". If the mode flag F1 has been reset to "0", that is, if the single-sheet feed mode, the process returns to the main routine. If the mode flag F1 is set to "1", that is, if the mode is the two-sheet feed mode, the feed flag F2 is set to "1" in step S235, and the process returns to the main routine.

FIG. 25 and FIG. 26 show a subroutine of a document discharge process by two-sheet feed executed in step S111 of the main routine of the second CPU 202. In this subroutine, the first document is discharged by the discharge roller 13 when the document is discharged.
1 and 132, the driving of the conveyor belt 125 is temporarily stopped, and the second document is temporarily put on standby on the platen glass 19, so that an appropriate interval is provided between the two documents. Thereafter, the transport belt 125 is driven to rotate again, and the two originals are discharged onto the discharge tray 135 with good alignment.

Specifically, steps S240 to S243
Are the same as steps S220 to S223, and the discharge process is started when the discharge flag F9 and the set completion flag F8 are set to "1" (see FIG. 6A). Then, in a step S244, it is determined whether or not the sensor SE4 is on-edge. If the sensor SE4 is not on-edge, the process proceeds to step S247, and if it is on-edge, it is determined in step S245 whether or not the document flag F10 is "0". If the document flag F10 has been reset to "0", that is, if the document whose leading end is detected by the sensor SE4 in step S224 is the first document, the conveyance motor is turned off in step S246, and step S247 is performed. Move to Thus, the second document is on standby on the platen glass 19, and only the first document is discharged (FIG. 6).
(B), (c), FIG. 7 (d)).

In step S247, it is determined whether or not the sensor SE4 is off edge. If the sensor SE4 is not off-edge, the process proceeds to step S252, and if it is off-edge, it is determined in step S248 whether or not the document flag F10 is "1". If the document flag F10 has been reset to "0", that is, if the document whose rear end is detected by the sensor SE4 in step S247 is the first document, the conveyance motor is turned on in step S250, and In step S251, the document flag F10 is set to "1", and the process returns to the main routine. 2 waiting on the platen glass 19
The discharge of the sheet is resumed (see FIG. 7E).

On the other hand, if it is determined in step S248 that the document flag F10 is set to "1", that is, in step S247, the document whose rear end is detected by the sensor SE4 is the second document. If there is, the discharge timer is set in step S249, and the flow shifts to step S252.

Steps S252 to S257 are the same as steps S226 to S231 described above. When the count of the discharge timer is completed, the discharge motor is turned off (YES in step S252, step S253), and the next document feeding process is executed. (NO in step S254, step S25
8) If the final document has been ejected, end processing is executed (YES in step S254, steps S255 to S255).
S257). Subsequently, in step S259, the discharge flag F
9 is reset to "0", the document flag F10 is reset to "0" in step S260, and this subroutine is terminated.

(Main part of the embodiment) In the above configuration,
When the leading edge of the first document is detected by the sensor SE4 at the time of discharging the document in the two-sheet feed mode, the transport motor is stopped (see FIG. 25, steps S244 to S246), and the trailing edge of the first document Is detected by the sensor SE4, the transport motor is driven again (FIGS. 25 and 26, step S247,
See S248 and S250). As a result, an appropriate space is provided between the first and second documents, and the two documents are discharged onto the discharge tray 135 with good alignment.

(Other Embodiments) The present invention is not limited to the above embodiments, but can be variously modified within the scope of the invention. For example, in the above embodiment, the pinch roller 12 is used as a means for registering the leading and trailing edges of a document.
Although the example using 1,122 is shown, a gate 129 can be used as shown in FIG. In this case, the gate 129 is installed on the downstream side in the feeding direction of the pinch rollers 121 and 122 so as to be able to advance and retreat with respect to the feeding path, and the upper pinch roller 121 can be moved toward and away from the lower pinch roller 122. ing.

In this case, the two-sheet feed mode is selected and A
When the DF start switch SSW is turned on, first, the pinch roller 121 is separated from the lower roller 122, and the gate 129 enters the feeding path. Documents stacked on the document tray 111 are picked up by a pickup roller 112.
The document is fed from the uppermost document D1 by the rotation of, and is separated by the forward / reverse rotation rollers 113 and 114.
21 and 122, it comes into contact with the gate 129, and a tip resist process is performed (see FIG. 27A). Thereafter, the gate 129 is retracted from the feeding path, the pinch roller 121 is pressed against the lower roller 122 to be driven to rotate, and the transport belt 125 is also driven to rotate forward. Thus, the document D1 is fed until the rear end passes through the gate 129 (see FIG. 27B).

Next, the gate 129 enters the feeding path, and the pinch roller 121 is separated from the lower roller 122. At the same time, the transport belt 125 is driven to rotate in the reverse direction in the direction of arrow c ′, the document D1 is fed back, and
The rear end resist process is performed by abutting the resist 29 (see FIG. 27C). In the state where the first document D1 has been subjected to the trailing edge registration processing,
The original D2 is fed, and the leading edge registration process is performed. As a result, the two originals D1 and D2 are continuously arranged side by side with the trailing edge registration and the leading edge registration performed by the gate 129.

In this state, the gate 129 is retracted from the feeding path, and the pinch roller 121 is moved to the lower roller 1.
22 and is driven to rotate, and
The originals D1 and D2 are simultaneously fed onto the original platen glass 19 (see FIG. 27D). And 2
When the rear end of the document D2 reaches a predetermined position on the platen glass 19, that is, the exposure start position by the optical system 20, the rotation of the pinch rollers 121 and 122 and the transport belt 125 is stopped.

On the other hand, in the processing for setting the original at the predetermined position, the control for stopping the feeding by the timer based on the rear end detection signal of the original by the sensor SE2 has been described. The original may be switched back by providing a stopper. That is, the document is once fed until it overruns a predetermined position, and then the transport belt 125 is reversed and switched back, and the rear end of the document is positioned in contact with the step or the stopper.

In the present invention, various means other than those described above may be employed for arranging two originals on the original platen glass 19 in parallel. For example, a so-called offset feed method in which a second document is fed following the first document in the separation section when feeding the document may be employed.

[Brief description of the drawings]

FIG. 1 illustrates an automatic document feeder (A) according to an embodiment of the present invention.
FIG. 1 is an internal configuration diagram of a copying machine provided with a DF).

FIG. 2 is a perspective view in which a part of the ADF is cut away.

FIG. 3 is an operation explanatory diagram showing a document feeding process in the ADF.

FIG. 4 is an operation explanatory view showing a document feeding process in the ADF, continued from FIG. 3;

FIG. 5 is an operation explanatory view showing a document feeding process in the ADF, continued from FIG. 4;

FIG. 6 is an operation explanatory diagram showing a document discharging process in the ADF.

FIG. 7 is an operation explanatory view showing the document discharging process in the ADF, continued from FIG. 6;

FIG. 8 is a plan view of an operation panel of the copying machine.

FIG. 9 is a block diagram of a control circuit of the copying machine.

FIG. 10 is a block diagram of a control circuit of the ADF.

FIG. 11 is a flowchart showing a control procedure (main routine) of the first CPU.

FIG. 12 is a flowchart illustrating a subroutine of a document feed mode switching process.

FIG. 13 is a flowchart illustrating a subroutine of a start process.

FIG. 14 is a flowchart showing a control procedure (main routine) of the second CPU.

FIG. 15 is a flowchart showing a subroutine of ADF start processing.

FIG. 16 is a flowchart illustrating a subroutine of a leading edge registration process of a document.

FIG. 17 is a flowchart illustrating a subroutine of a document size detection process.

FIG. 18 is a flowchart illustrating a subroutine of a document feeding process in the single-sheet feed mode.

FIG. 19 is a flowchart illustrating a subroutine of a document feeding process in a two-sheet feed mode.

FIG. 20 is a flowchart showing a subroutine of a document feeding process in the two-sheet feed mode, and is a continuation of FIG. 19;

21 is a flowchart showing a subroutine of a document feeding process in the two-sheet feed mode, and is a continuation of FIG. 20.

FIG. 22 is a flowchart showing a subroutine of a document feeding process in the two-sheet feed mode, and is a continuation of FIG. 21.

FIG. 23 is a flowchart illustrating a subroutine of a document discharging process in the single-sheet feed mode.

24 is a flowchart showing a subroutine of a document discharging process in the single-sheet feed mode, and is a continuation of FIG. 23.

FIG. 25 is a flowchart illustrating a subroutine of a document discharge process in a two-sheet feed mode.

26 is a flowchart showing a subroutine of a document discharging process in the two-sheet feed mode, and is a continuation of FIG. 25.

FIG. 27 is an operation explanatory diagram showing a document feeding process in a modification of the document registration means in the ADF.

[Explanation of symbols]

 Reference Signs List 100 automatic document feeder (ADF) 110 document feeder 111 document tray 112 pickup roller 120 document feeder 121, 122 pinch roller 125 transport belt 130 document discharger 131, 132 discharge roller 135 ... Ejection tray SE1-SE4 ... Photo sensor for document detection

Claims (1)

(57) [Claims] A first position on the platen and a second position adjacent to the first position in the document conveying direction;
A document conveying belt for stopping two consecutive documents arranged side by side at the first position and the second position, and discharging the document from the platen after completion of the exposure operation, and discharging the document from the platen by the document conveying belt. An automatic document feeder having a discharge means for receiving and discharging a document to be fed onto a tray, after the first document is delivered to the discharge means by driving the document transport belt, the drive of the document transport belt is temporarily stopped. Stopping the document, then restarting the driving of the document transport belt, and delivering the second document to the discharge means.