JPS6148828A - Image forming device - Google Patents

Abstract

PURPOSE:To perform image forming operation for the 1st and the 2nd originals automatically and continuously without replacing the originals by interrupting the image forming process of the 1st original and forming the image of the 2nd original on a form stored in an intermediate tray, and then performing cycles of the image formation for the 1st and the 2nd originals. CONSTITUTION:The originals A and B are set side by side on an original platen 1, a copy of the original A is taken (1st copying cycle), and then transferred materials after the 1st cycle of copying operation are stacked in the intermediate tray 39 successively. When the transfer materials after the 1st copying operation are stacked successively up to the permissible number, the 1st cycle of copying operation for the original A is interrupted temporarily. Then, a scan on the original B on the original platen 1 is made and said transfer materials after the 1st copying of the original A are refed, sheet by sheet, from the intermediate tray 39, so that the original B is copied on the refed transfer materials (2nd cycle of copying) until all the transfer materials are sent out of the intermediate tray 39.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention [Field of Industrial Application] The present invention relates to an image forming apparatus such as a copying machine. More specifically, the present invention relates to an image forming apparatus capable of forming images multiple times on both sides of a sheet and/or on the same side.

[Conventional technology]

For convenience, a copying machine will be described as an example of an image forming apparatus.

2. Description of the Related Art Copying machines having a double-sided copying function that forms images on both sides of a sheet of paper and a multiple copying function that forms images multiple times on the same side of a sheet are well known.

Specifically, the copy execution mechanism and the copy execution mechanism m1
An intermediate tray temporarily stores the paper that has been copied for the first time, and the paper that has been copied for the first time stored in the intermediate tray is sent to the copy execution mechanism again for the second copy processing (duplex copying/multiple copying). and a feeding mechanism.

FIG. 7 is a schematic diagram of the intermediate tray portion of the duplex/multiple copying machine as described above. Reference numeral 39 denotes an intermediate tray, onto which the paper P1 that has been subjected to the first copying process by a copy execution mechanism (not shown) is introduced via the introduction means 38 and stored. In the case of multi-copying (copying multiple sheets), the first-copied sheets P1 are sequentially fed and stacked and stored one after another on the tray 39. The stored paper P1 is then separated into individual sheets by the sheet-by-sheet separation and feeding means 40 for the second copying process, and is again fed to the copy execution mechanism via the sheet path 42.

[Problem that the invention seeks to solve]

By the way, the paper PL that has been copied for the first time is generally curled to a greater or lesser extent by passing through a heat roller in the copying execution mechanism and undergoing image fixation.
As shown in a slightly exaggerated manner in FIG. 6, the curled paper P1 is deposited on the paper 9. Therefore, the apparent number of sheets that can be stored in the intermediate tray 39 decreases. When the accumulation progresses to a certain extent, the leading edge of the next sheet to be fed hits the curled rear edge of the paper Pi stored in the intermediate tray, as shown by the two-dot chain line, causing paper jamming and other irregular feeds. It's easy to do.

In order to increase the number of sheets that can be stored in the intermediate tray 39, the position of the paper feeding means 38 with respect to the intermediate tray 39 must be raised to increase the space between the two 38 and 39. There is a problem like this.

Since a large space is required between the ωΦ human tray 39 and the paper feeding means 38, the entire copying machine becomes larger.

■It becomes necessary to provide a mechanism for correctly storing a large amount of curled paper P1, for example, a mechanism for pressing down the paper that is sequentially fed onto the tray 39 and stored, which increases the complexity of the machine. Maneku.

■When the amount of paper stored on the intermediate tray 39 is large, it becomes difficult to stably and reliably separate and re-feed that large amount of paper to the copy execution mechanism one by one until the last one, which reduces reliability. It is easy to become lacking.

■Furthermore, considering the case where double feeding of paper occurs during the first copying or the second copying, the paper PL from the intermediate tray 39
After all sheets have been fed out, the occurrence of double feeding can be detected by comparing the number of sheets fed during the first copy with the number of sheets re-fed from the intermediate tray 39. When searching for double fed sheets, the work becomes difficult if there are a large number of sheets, and a large number of sheets are wasted when copying all at once.

Therefore, in order to avoid the above-mentioned problems, actual double-sided
In many multi-overlap copying machines, the intermediate tray 39 is often designed so that the number of sheets that can be stored is relatively small.

However, if the number of sheets that can be stored in the intermediate tray 39 is relatively small, the maximum number of double-sided and multiple copies that can be processed continuously is also limited to the small number of sheets that can be stored in the intermediate tray 39. .

For this purpose, the number of sheets that can be stored in the intermediate tray 39 (the maximum number of double-sided/multiple copies that can be processed continuously) is determined.
When the required number of copies is n, the case where m<n often occurs in actual copying work.

In such cases, double-sided/multiple copying involves dividing the copying process into two or more parts, and ultimately creating the required number of copies. It also has to be replaced, etc., resulting in poor workability and efficiency.

Specifically, FIG. 8 is a copying work flow diagram in the case of copying where man≦2m.

Step I: Set original A for first copying on the original table of the copying machine.

Step H = Duplex or multiple copy mode selection designation.

Step m=Number of copies Set the number of copies to m, which is the number of sheets that can be stored in the intermediate tray 39, using the number key.

Step ■ = Press the copy button to copy original A. As a result, m sheets of first-copied paper Pl are stored in the intermediate tray 39.

Step V=Remove original A from the original table and set original B for second copying.

Step ■=Press the copy button, thereby transferring the first copied sheet P1 from the intermediate tray 39 to the copy execution mechanism.
The sheet is re-fed, a second copying process is performed on the sheet, and m double-sided or multiple copies are sequentially output to the outside of the copying machine.

Step ■=Remove the B original from the original table and set the A original again.

Step m = Number of copies remaining by pressing the number key (
n − m).

Step ■=Press the copy button to copy the A mE draft, which results in (n - m) sheets of first copied paper P
L is stored in the intermediate tray 39.

Step X--Remove original A from the original table and set original B again.

Step mowing=Press the copy button, thereby transferring the first copied sheet P1 from the intermediate tray 39 to the copy execution mechanism.
The sheet is re-fed, a second copying process is performed on the sheet, and (n-m) double-sided or multiple copies are sequentially output to the outside of the copying machine.

Thus, through all the above operations, the required n double-sided or multiple copies can be finally obtained. Note that in the above flow, any of steps I to m may be performed first.

If n>2m, repeat steps r~■ twice or more the necessary number of times, then perform step ■~mowing, and finally n(>2m).
The procedure is to obtain 2 m) double-sided or multiple copies.

The present invention has been proposed in view of the above, and includes
Even when the number m of sheets that can be stored in No. 9 is relatively small and the above-mentioned man copy conditions are met, it is possible to automatically and continuously copy the required number of n sheets without having to reposition the original. It is an object of the present invention to provide an image forming apparatus of this type which is capable of performing the following operations, and therefore has very good workability and efficiency.

1. Configuration of the Invention [Means for Solving Problems] The present invention provides an A-B scan function that separately scans a first document and a second document placed and set side by side on a document table, and an image forming function. The execution mechanism feeds the paper on which the image of the first original has been formed to an intermediate tray and stores it therein, and performs image formation on the paper stored in the intermediate tray so as to form an image of the second original on the paper. It has a machine 17 that performs double-sided or multiple image formation on the same sheet by refeeding it to the mechanism, and executes multiple-sheet image forming processing in A-B scan mode, double-sided or multiple image forming mode. In this case, in the middle of the image forming process for the first document being executed a set number of times, the image-formed paper for the first document that is fed and stored in the intermediate tray becomes the paper in the intermediate tray. When the number of sheets that can be stored is reached, the image forming process for the first document is interrupted until the number of sheets reaches that number, and the sheets stored in the intermediate tray are sequentially re-fed to the image forming execution mechanism, and the remaining sheets are After that, the cycle of image formation on the first document and image formation on the second document is performed again, and double-sided or multiple image formation is performed for the required number of images formed at the beginning. The gist of the present invention is an image forming apparatus characterized in that it is configured to automatically perform processing until a processed sheet is output.

[Effect]

The so-called A-B scan system self-mechanism that separately scans a first original and a second original set side by side on a document table is well known, and although detailed explanation thereof will be omitted, fJS2
As shown in the figure, side A of the first original (left page side of the original OR in this example) and side B of the second original (right page side in the same example) placed side by side on document table 1 are mirrored. Scanning process a1 separately by a scanning member (not shown) such as a photoelectric reading element
・a2 (b+ ” bz is the return of the scanning member).

By utilizing this A-B scan, the present invention has made it possible to automatically and continuously perform double-sided or multiple image formation on a large number of sheets, which exceeds the number of sheets that can be stored in the intermediate tray 39, in a single scan. It is something. That is, as shown in the flowchart of FIG. 3, in step E, original A as a first original and original B as a second original are placed and set side by side on an original table.

Step II = Duplex copy mode or multiple copy mode selection.

Step III = A@B scan mode selection.

Step ■ = Set the required number of copies.

Step V = Copy button - on.

After the above steps, the above-mentioned automatic control allows the document to be printed on both sides or with multiple images for the required total number of documents, even if the number of sheets that can be stored in the intermediate tray 39 is relatively small. Output without any work.

〔Example〕

FIG. 1 is a longitudinal sectional front view showing a schematic configuration of an embodiment of the apparatus (an electronic copying machine capable of double-sided and multiple copying).

■ is a fixed document table such as a transparent glass plate placed on the top of the exterior of the copying machine.The document is placed at a predetermined position on the top of this document table with the image side to be copied facing downward, and then the original is placed on top of the document table. Cover with a document pressure bonding plate (not shown) to set the document. A・B
When copying is to be performed in the scan mode, the A original and BFFl are placed and set side by side on the original table l.

Reference numeral 2 denotes a moving optical system that scans a downward image surface set on the document table l, and has an A-B scan function.

3 is a drum-type photoreceptor that is rotated at a predetermined circumferential speed in the direction of the arrow; Uniform −12 electrons by the electric device 4 → Original image exposure (slit exposure) by the optical system 2 → Development action of the electrostatic latent image formed on the photoreceptor surface by the first developer 5 or the second developer 6. As a result, a toner image corresponding to the original image is formed on the circumferential surface of the photoreceptor. The toner image forming surface passes through a pre-transfer position (for stabilizing the potential on the photo-conductor uniformly before transfer) by the subsequent rotational drive of the photo-conductor, and then passes through the position of a transfer charger 8. During the process of passing through the transfer charger 8 position, the toner image on the surface of the photoreceptor 3 is transferred to the surface of the transfer material fed between the photoreceptor 3 and the charger 8 in synchronization with the rotation of the photoreceptor. are sequentially transferred.The portion of the transfer material that has passed through the transfer device 8 is sequentially separated from the photoreceptor surface by the action of the peeling charger 9.The photoreceptor surface from which the transfer material has been peeled off is transferred It is subjected to the action of a charger 10 to facilitate the removal of residual toner from the photoreceptor surface, and then subjected to the removal of transfer residual toner by a cleaner 11,
It is again subjected to the action of the charger 4 for image formation.

- In this example, the transfer material is fed from the manual feed tray 12,
The transfer material manually set on the manual feed tray 12 is fed selectively from three paper feed systems: t51 paper feed from cassette 17, second cassette).
3. The auxiliary timing roller pair 14 transports the sheet through the first sheet path 15 to the main timing roller pair 16, and the main timing roller pair 16 aligns the timing with the leading edge of the toner image on the photoreceptor 3, and the photoreceptor 3 and charger 8 The image is fed to the transfer section between the two. The transfer material in the first cassette (17) is edged one by one by a feeding roller 18, and is conveyed to a pair of main timing rollers 16 through a second sheet path 19. The transfer material in the second cassette 20 is edged one by one by the feeding roller 21, and is conveyed to the main timing roller pair 16 through the third sheet path 22Φ sub-timing roller pair 23.

The transfer material passed through the transfer section 8 and sequentially separated from the surface of the photoreceptor 3 by the charger 9 is transferred to a pair of fixing rollers 25 by a conveyor belt 24.
The toner image is guided through the nip and passes between the pair of rollers, where the toner image is fixed.

Reference numeral 26 denotes a first deflector for changing the course of the transfer material exiting between the pair of fixing rollers 25, which is selectively controlled to be switched between a first switching attitude shown by a solid line and a second switching attitude shown by a two-dot chain line.

When the first deflector 26 is in one-sided copy mode,
In the double-sided or multiple copying mode, during the second copying process, the fixing roller pair 2 is held in the second switching posture.
The transfer material that has been copied on one side, or the transfer material that has been copied on both sides or multiple times passes through the upper surface side of the deflector 26 and passes through the path of the fourth sheet path 27 → paper ejection roller pair 28 → paper ejection port 2.9. and is discharged onto a tray 30 outside the machine.

On the other hand, during the first copying process in the duplex or multiple copying mode, the first deflector 26 is held in the first switching position, and the first copied transfer material exiting the fixing roller pair 25 is The sheet is introduced into the fifth sheet path 31 through the lower surface side of the deflector 26 .

Reference numeral 33 denotes a second deflector for changing the course of the transfer material, which is disposed in the middle of the fifth sheet path 31, and is controlled to be selectively switched between a first switching posture shown by a solid line and a second switching posture shown by a two-dot chain line. Ru. Reference numeral 32 denotes a pair of transfer material intermediate conveyance rollers disposed in the middle of the fifth sheet path 31 between the first deflector 26 and the second deflector 33.

The above-mentioned second deflector 33 is held in the first switching posture in the double-sided copying mode, and the transfer material entering the fifth sheet path 31 passes through the left side of the deflector 33, and at that point the forward rotation a The sheet is conveyed to a sixth sheet path (switchback sheet path) 35 via a forward/reverse rotation roller pair (switchback roller pair) 34. When the trailing edge of the conveyed transfer material finishes passing the second deflector 33 position, the forward/reverse rotation roller pair 34 is driven in the reverse direction,
As a result, the transfer material carried into the sixth sheet path is reversely conveyed and guided to the first pair of rollers 36 for introducing the transfer material to the intermediate tray 39 that has passed through the lower surface side of the second deflector 33. 38 is a second introduction roller pair disposed in front of the first introduction roller pair 36; 37 is a transfer material path switching fj disposed between the first and t52 introduction roller pairs 36 and 38;
53 deflector, and the size of the transfer material used is large.
Alternatively, when the length is long, the transfer material is held in the first switching posture shown by the solid line, and the transfer material is directly transferred from the four-person roller pair 36 to the intermediate tray 39, J: with the image surface facing upward.
It will be introduced and stored. Further, when the size of the transfer material used is small or the length is short, it is held in the second switching posture shown by the two-dot chain line, and the transfer material coming out from the first introduction roller pair 36 is moved to the deflector 37. The sheet is guided through the upper surface of the sheet to the second introducing roller pair 38, and is introduced and stored from the second introducing roller pair 38 onto the intermediate tray 39 with the image surface facing upward. In the case of double-sided copying of a large number of sheets, the transfer materials that have been copied for the first time are sequentially introduced onto the intermediate tray 39 along the above-mentioned path, and are deposited and stored.

On the other hand, in the multiple copying mode, the second deflector 33 is held in the second switching attitude, and the transfer material entering the fifth sheet path 31 is guided to the first introduction roller pair 36 through the upper surface side of the deflector 33. , directly from the first pair of introducing rollers 36, or via the upper surface of the third deflector 37 in the second switching position and then the second pair of introducing rollers 38, and is introduced and stored in the intermediate tray 39 with the image surface facing downward. In the case of multiple copying of a large number of sheets, the transfer materials that have been copied for the first time are sequentially introduced onto the intermediate tray 39 along the above-mentioned path, and are deposited and stored.

Reference numeral 40 designates a feeding roller mechanism for one sheet of transfer material, consisting of a feeding roller 40a and a double feeding prevention roller 40b, which is disposed on the front end side of the intermediate tray 39, and is arranged on the front end side of the intermediate tray 39. In this example, the material is delivered one sheet from the bottom and re-supplied to the transfer unit 8 along the path of intermediate conveyance roller pair 41 - seventh sheet path 42 → auxiliary timing roller pair 23 → main timing roller pair 16. sent.

In this case, as described above, in the double-sided copying mode, the first copied transfer material is introduced and stored in the intermediate tray 39 with the image surface facing upward, so that the transfer material cannot be re-fed to the transfer section 8. The side of the transfer material opposite to the first copied side is fed facing the photoreceptor surface, the second copy is made on that side, and a double-sided copy is output on the paper output tray 30. be done. In the case of multiple copying mode, since the transfer material that has been copied for the first time is introduced and stored in the intermediate tray 39 with the image surface facing downward, the refeeding of the transfer material to the transfer section 8 is carried out in the first copy of the transfer material. The surface that has been copied for the first time is fed facing the photoreceptor surface, a second copy is made to that surface, and multiple copies are output to the paper discharge tray 30.

Figure 4 shows a plan view of the operation panel of the copying machine.
is the A/B scan mode selection key, 44 is the duplex copy mode selection key, 45 is the multiple copy mode selection key, 46 is the numeric keypad for setting the number of copies, 47 is the clear key, 48 is the number of copies display, and 49 is the copy button. be. It has a background density adjustment dial, a transfer material size selection key, a variable magnification key, etc., but these are omitted from the figure.

FIG. 5 is an operational flow of the control circuit system associated with mode selection.

When the double-sided copying mode or the multiple copying mode is selected by the step E key 44 or 45, the control circuit system becomes the selected mode execution system.

Step ■=When either key 44 or 45 is released, the control circuit system becomes a normal one-sided copy mode execution system. In this case, by setting the original on the original table l, setting the required number of copies n, and pressing the copy button 49, one-sided copying for the set number of sheets will be automatically and continuously performed.

Step (2) = When the duplex or multiple copying mode is selected and the A-B scan mode is selected by the key 43, the control circuit system becomes the selected mode execution system.

Step (2)=Next, when the required number of copies n is set using the key 46, the number n is compared with the number m of transfer materials that can be stored in the intermediate tray A 39.

When step V=n>m, it is impossible to store all first-copied transfer materials for the set number of sheets in the intermediate tray 39, so automatic batch copying according to the present invention as described above is performed. Duplex or multiple copying in mode is performed.

When step VI=n≦m, all the first-copied transfer materials for the set number of sheets can be stored in the intermediate tray 39, so in this case, double-sided or multiple copying in the normal automatic copying mode is possible. executed.

Step ■=If the A@B scan mode is not selected in step ■, and then the required number of copies n is set, that is, for double-sided copying or multiple copying, A and B are first scanned. When performing double-sided copying or multiple copying, the procedure is to set the document on the document table and execute the first copying process, then replace the A document on the document table with B document and execute the second copying process. . In this case as well, a comparison is made between the set number of copies n and the number m of transfer materials that can be stored in the intermediate tray 39.

When step (2)=n≦m, it becomes possible to perform double-sided or multiple copying processing using a procedure that does not involve the above-mentioned A/B scanning.

When step ■=n>m, it is impossible to store all the first-copied transfer materials for the set number of sheets in the intermediate tray 39, so double-sided or multiple copying processing using the above procedure is impossible. , and a display to that effect will be made. Specifically, the sheet number display 48 is made to display an error code or the like indicating that copying is not possible, a separate warning display section is provided to display a message that copying is prohibited, such as "rMAXOo My Made," and the sheet number display section 48 is flickered. If the copy button 49 is still pressed, the first copy is performed for the number of sheets that can be stored in the intermediate tray 39, and then the remaining number of sheets is displayed. .

FIG. 6 is a more detailed flowchart of step V in the flow of FIG. 5 described above.

When the copy button 49 is pressed, a counter indicating the remaining number of required copies is set to the set number of copies n, and a counter k for the number of transfer materials in the intermediate tray is set to 0 (step Im).

With the A-B scan function, copying (first copying) of A original of A original and B original set side by side on document table l is executed, and the transfer material that has been copied for the first time is sequentially copied. is stored in the intermediate tray 39 (step rv-v).

Each time one copy is executed, the sentence is subtracted by 1, and k is incremented by 1 (step ■).
The acid reaching the introducing roller pair 36 passes through the photoelectric sensor 50 (
1), etc., and subtracting and adding k by 1 based on the signal.

When the first-copied transfer material is sequentially introduced into the intermediate tray 39 and reaches =m (step ■), the first copying process for the A original is temporarily interrupted.

Then, the B original on the document table l is scanned, and the copied transfer material for the A original (the first copied transfer material) is re-fed one by one from the intermediate tray 39. , the copying (second copying) of the B original is performed on the re-fed transfer material until all the transfer materials in the intermediate tray 39, that is, m sheets, are exhausted, and the A.8 sheets are placed on the paper ejection tray 30. The transfer material presence sensor 51 of the intermediate tray 39 detects that all the transfer materials in the intermediate tray 39 have been re-fed when double-sided or multiple copies of the original are output (steps ① to X). Alternatively, the transfer material passage detection sensor 52 may be disposed in the middle of the seventh sheet path 42, and k may be subtracted by 1 each time the transfer material passage is detected, and detection may be performed when k becomes 0. . In this case, at the time when = 0, the transfer material presence sensor 5 of the intermediate tray 39
Depending on whether or not No. 1 detects that there is no transfer material, it is possible to detect double feeding of transfer materials that may occur during the A original copying process and the B original copying process.

The last sheet of transfer material in the intermediate tray 39 is fed again,
When the second copying process is completed, the process returns to step m, k is set to 0, and steps ■
-X are repeatedly executed, and finally a set number n of double-sided or multiple copies are outputted to the paper discharge tray 30, and the entire copying cycle is completed (step X[I).

In step (2), even if k has not reached m, if the number of remaining copies becomes 0 (step XI), no further copying is necessary, and the copying process for original B begins. If k has not reached m and the number of copies remains, copying of original A is continued.

In a copying machine having a document size detection means.

If the set original is of a size that cannot be copied using A-B scan mode, a message to that effect will be displayed, and if the original size is possible, you can select A-B scan mode to process multiple double-sided or multiple copies. It is also possible to display a message to that effect. In addition, in the case of copying with the A-B scan mode selected, the first copying process is performed on the B original, and the first copying process is performed on the A original, depending on the placement position and direction of the A original and B original on the document table 1. It is also possible to perform a second copy process.

When copying in the A-B scan mode, it is also possible to have the automatic document feeder automatically set two documents, an Am document and a B document, on the document table 1.

Fig. 9 is a schematic diagram of an example of a specific automatic document feeder, Fig. 10 is a partially enlarged view of the device, and Fig. 11 is a normal document feeder (automatic feeding of originals one by one onto the document table). Feeding/
Operation time chart for discharging mode), t
FIG. 512 is an operation time chart in the case of a mode in which two sheets of originals are continuously fed.

Reference numeral 60 denotes a sheet original stacking tray disposed on the right side of the original table l, on which a plurality of sheet originals 0 are stacked and set with the image surface facing downward.

(1) In the case of normal document feeding ■ The first electromagnetic clutch CL (not shown) is turned on (FIG. 11) by the document feeding start signal from the control circuit, and the document feeding roller 61 and separating roller 62 are turned on (FIG. 11). is driven to rotate. As a result, only the lowest one of the sheets 1 and O on the tray 60 is separated and sent toward the document table l.

(2) 63 is a feeding document sensor. When the sensor 63 detects that the leading edge of the document has been reached, the signal turns on the second electromagnetic clutch CR, 2 (not shown) (FIG. 11) and transfers the relay conveyance roller pair 64 and the upper surface of the document table l. The endless rotating belt 65 for document conveyance, which is in contact from the right side to the left side, is driven to rotate in the direction of the arrow. 65aφ65b
are the drive roller and turn roller of the belt.

■The first magnetic clutch CL is turned off after a predetermined time (time determined by the machine arrangement) after the arrival of the leading edge of the document is detected by the sensor 63, and the document feed roller 61 and the separation The rotation of the roller 62 is stopped.

However, the leading edge of the fed document has already been gripped by the pair of intermediate conveying rollers 64, and continues to be fed by the rotational force of the pair of rollers.

(2) The document then enters between the document table 1 and the rotating belt 65, and is conveyed to the left side of the document table while sliding on the upper surface of the document table 1 by the rotating force of the belt 65.

(2) The sensor 63 then detects passage of the trailing edge of the fed document.

The size of the fed document (length in the feeding direction) is determined by the calculation section of the control circuit according to the time T from when the sensor 63 detects that the leading edge of the fed document has arrived until it detects that the trailing edge has passed. ) is detected.

(ΦThe first electromagnetic clutch CL2 is kept on from the time when the sensor 63 detects the passage of the trailing edge of the fed document until a time t1 determined by the size of the one-passed document and the machine layout has elapsed. At this point, it is turned off and the drive of the roller pair 64 and rotating belt 65 is stopped.At this point, the leading edge of the document fed onto the document table L is exactly at the reference position on the left side of the document table surface. The document is now set at a predetermined position on the document table 1.

■Next, the copying process for the above-mentioned sect original is performed on the copying machine main unit side, and after that, the next original is automatically fed again by the operations from ■ to ■ above. The copied original is automatically ejected to a paper ejection tray 66 on the left side of the original table by rotating the rotating belt 65 again.

(2) Continuous feeding of two originals ■ When the A-B scan selection key 43 is pressed, the original feeding control circuit system is set to this mode.

■'' In the case of bipedal (1) term ■~■ and turning movement, first original v40! is automatically fed.

(2) When the passage of the rear end of the 11th original is detected by the sensor 63, the first electromagnetic clutch CLI is turned on again (FIG. 12), thereby starting the feeding of the second original.

■Furthermore, when a predetermined time t2 (time determined by the machine configuration) has elapsed from the time when the rear end of the first document is detected by the sensor 63, the second electromagnetic clutch CL2 is turned off. Feeding of the EC document 01 is temporarily stopped. At this time, the document O1 is waiting with its trailing end just coming out of the relay conveyance roller pair 64 as shown in FIG.

(2) The second electromagnetic clutch CL2 is turned on again after time t3 has elapsed since the arrival of the leading edge of the second document 02 fed in (2) above at the sensor 63 position is detected. At this point, the leading edge of the second original 02 has reached the nip portion of the pair of relay conveyance rollers 64, and the second electromagnetic clutch CL2 is turned on, so that the first and second originals o1 and 02 are mutually moved. In a substantially connected state, the documents are conveyed on the document table l toward the left side of the document table by the conveyance force of the rotary belt 65.

(ΦThe first electromagnetic clutch CL is turned off after a time L0 after the leading edge of the two originals [1] is detected by the sensor 63. However, the second original fI02 is already held between the pair of relay conveyance rollers 64. Since it is loaded, it will continue to be transported.

■The clutch CL2 is turned off after time t4 from the time when the second electromagnetic clutch CL2 in the above ■ is turned on again.
Feeding of the first and second originals O1 and 0□ is stopped.

As a result, as shown in FIG. 75g, the automatic feeding Φ set state is established with the two originals O8 and 02 arranged side by side at predetermined positions on the original table l.

■After copying the above manuscript OL ・02,
The next two originals are automatically fed by the operations ① to ② above. At this time, the rotating belt 65 rotates again, and the two copied originals OL.02 are automatically sequentially discharged onto the tray 66.

In addition, in the time charts of Figures 11 and 12, t3=t
2, and t4 is 1. -12 is the time calculated.

FIG. 13 shows a flowchart for automatically switching the mode or displaying that execution is not possible due to automatic document size detection. If the size of the document that allows two sheets to be placed on the document table is defined as small size, if the document is small and n>m, normal duplex/multiplex operation (mode ■) will be used, and if n>m, A- Whether B scan is selected or not, A-B scan double-sided multiplex operation (mode ■) is automatically activated.
Two originals are continuously fed from the automatic document feeder, and the operation of the present invention enables automatic double-sided multiple copying of a large number of sheets. Also, if the original size is not small, if A/B scan is selected, it will be displayed as disabled (mode ■), and even if n > m, the above-mentioned display will be displayed as disabled. It is.

Note that the present invention is not limited to the above embodiments,
For example, various methods of stopping a document at a fixed position in an automatic document feeder are known in the past, and this technique is applied to the document 2 of the present invention.
It is possible to adapt to continuous sheet feeding. C. Effects of the Invention As described above, according to the present invention, the number m of sheets that can be stored in the intermediate tray is relatively small, and therefore the image forming apparatus is small. Also, it is possible to automatically and continuously perform double-sided or multiple image forming processing for an amount greater than m without having to reposition the document midway.

Therefore, the workability and fat percentage are very good, and the intended purpose is well achieved.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional front view showing a schematic configuration of an apparatus according to an embodiment of the present invention, Fig. 2 is an explanatory diagram of the A-B scan mode, Fig. 3 is a flowchart of the double-sided or multiple copying procedure, and Fig. 4 is the operation. A plan view of the board, Figure 5 is an operation flow diagram, Figure 6 is an automatic control flow diagram, Figure 7 is an enlarged side view of the intermediate tray section, Figure 8 is a conventional double-sided or multiple copying procedure flow diagram, and Figure 9 is a flow diagram of the conventional duplex or multiple copying procedure. The figure is a schematic diagram of the automatic document feeder, Figure 10 is a partially enlarged view, and Figure 1
Figure 1 and Figure 12 are automatic feeding time charts, respectively.
Figure 3 is a flowchart of copy mode switching based on document size detection. 1 is a document table, 3 is a photoreceptor, and 39 is an intermediate tray. -] Figure 6

Claims (2)

[Claims] (1) The first and second originals placed and set side by side on the document table
It has an A/B scan function that scans the original and the original separately, and an image forming execution mechanism that feeds the paper on which the image has been formed for the first original to an intermediate tray and stores it, and the paper stored in the intermediate tray is used as the paper. It has a function to perform double-sided or multiple image formation on the same sheet by refeeding it to the image forming execution mechanism to perform image formation on the second document, A/B scan mode, double-sided Or, when multiple image forming processing is executed in the multiple image forming mode, the image forming process for the first document is fed and stored in the intermediate tray during the process of executing the required number of image forming steps for the first document. When the number of sheets of paper on which images have been formed for the first document reaches the number of sheets that can be stored in the intermediate tray, the image forming process for the first document is interrupted after that number of sheets, and the sheets stored in the intermediate tray are sequentially The image formation execution mechanism is caused to refeed the paper and execute image formation on the second original, and then repeat the cycle of image formation on the first original and image formation on the second original again for the first time. An image forming apparatus characterized in that the image forming apparatus is configured to automatically execute the process until a required number of sheets of image forming sheets set as double-sided or multiple image forming sheets are outputted. (2) Equipped with an automatic document feeder that has a function to automatically detect the size of fed documents, a mode for forming multiple images on the same sheet of paper is selected, and the set number of sheets for image formation can be stored in the intermediate tray. In the case where the number of originals exceeds the number of sheets and the size of the original allows two sheets to be placed on the document table, the document feeding device feeds the two documents consecutively onto the document table. The image forming apparatus according to scope (1).