JPS59218464A - Double-face copying method of double-faced original - Google Patents

Abstract

PURPOSE:To obtain double-faced copies from double-faced originals automatically without changing the order of page of originals at all and eject transfer paper in the same order of page as originals, by providing switching pawls to invert originals. CONSTITUTION:In a cyclic double-faced original automatic supply device A, a switching pawl 12 switches the first original paper path 1a and the eighth original paper path VIIa. A switching pawl 13 switches the fourth original paper path IVa and the sixth original paper path VIa. Sensors 14, 15, 16, 17, and 18 detect the front end or the rear end of the original paper in the movement direction. In a double-face copying machine body B, the lower end of the third transfer paper path IIIb is connected to the sixth transfer paper path VIb, and the upper end of the fifth transfer paper path Vb is connected to the sixth transfer paper path VIb and the fourth transfer paper path IV, and the upper end of the fourth transfer paper path IVb is connected to the first transfer paper path I b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic double-sided copying method, and more particularly to a double-sided copying method for forming an original image on both the front and back sides of a transfer sheet from a double-sided sheet original.

Conventionally, as a device that performs double-sided imaging using a circulation method,
A method has been used in which one side of the original is copied onto each side of copy paper, the resulting one-sided copies are stored in an intermediate tray, and the sheets are re-fed from 7c, etc., to sequentially copy on the back side. For this reason, if the copy paper jams during the process, the page order will be incorrect, so all the copy paper left in the intermediate tray after single-sided copying and after double-sided copying are discarded. There was the inconvenience of having to redo the copy.

Conventionally, in order to eliminate this drawback, a method has been devised in which a double-sided copy is obtained by reversing the front and back sides of each document using a circulation type double-sided copying method.

This starts copying from the second page or the second page from the end of the original, and after double-sided copying is completed, the copy is turned over again along with the original, and then the copied side is stacked on the output tray with the copied side facing down, making the same page as the original. You will get a double-sided copy of the order.

However, with this method, it is not possible to start copying from the first page or from the end of the manuscript;
After double-sided copying, the copy must be reversed to obtain the same page order as the original, which inevitably complicates the mechanism.

Also, when obtaining a single-sided copy from a double-sided original, you will not be able to obtain a copy in the same page order as the original unless you start copying from the first page from the end, so after flipping the original and placing it on the platen, The document had to be reversed, placed again, started copying, reversed again, and copied the back side, which resulted in a time loss and a longer path, which had an adverse effect on the document.

The present invention provides a double-sided copying method using a double-sided original, which eliminates the drawbacks of the prior art described above and does not require a mechanism for reversing the transfer paper after double-sided copying.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of one embodiment of the present invention, showing each element and the path of the original and transfer paper.

In Figure 1, A is a circulating double-sided automatic document feeder, B is
is a duplex copying machine that makes double-sided copies. Reference numeral 1 denotes a paper feed tray, which is tilted downward to the left side. Adjacent to the left side of the paper feed tray 1, a paper feed belt driven roller 2a
A paper feed belt 3 is provided on the paper feed belt driven roller 2a.
The paper feed belt drive roller 2 is wrapped around the other end of the paper feed belt 3.
Install. The paper feed belt 3 is a paper feed belt driven roller 2a.
The paper feed belt is wound around the drive roller 2 and rotated in the direction of arrow C. Paper feed belt drive roller 2,
The paper feed belt drive roller 2a is configured to rotate in the same direction as the paper feed belt 3 (direction of arrow C). 4 is a separation belt drive roller, 4a is a separation belt driven roller, which is arranged above the paper feed belt drive roller 2, and these two rollers, that is, separation belt drive roller 4 and separation belt driven roller 4a, are separated. A belt 5 is wound around it, and this separation belt 5 is designed to rotate in the direction of the arrow. In this way, between the separating belt 5 and the paper feed belt 3, one sheet of the sheet-like original placed on the paper feed tray 1 is separated from the bottom. Reference numeral 6 denotes the left roller, that is, a conveyance roller located below and to the left of the paper feed belt drive roller 2, and left and right rollers 6 are provided on both sides of the conveyance roller 6.
b, 6a are press contact. Reference numeral 7 denotes a conveyor belt drive roller, which is located below the paper feed belt drive roller 2, and this conveyor belt drive roller 7 rotates in both forward and reverse directions.

7a is a conveyor belt driven roller, and a conveyor belt 8 is wound between the conveyor belt drive roller 7 and the conveyor belt driven roller 7a. And the conveyor belt driven roller 7a
is located at the right end of the double-sided automatic document feeder A. 9 and 10
are the first and second switchback mechanisms, respectively, and the first
The switchback mechanism 9 is located below and to the left of the left roller 6b.
The switchback mechanism 10 is located to the upper left of the separation belt driven roller 4a. Reference numerals 11 and lla designate sheet discharge rollers, which are located above the separation belt drive roller 4, and the sheet discharge rollers 11 and lla are arranged vertically and pressed against each other.

These paper ejection rollers 11 eject the copied original onto the paper feed tray 1. Paper discharge roller 11a.

The conveyance force of the switchback mechanism 11 is weaker than the conveyance force of the switchback mechanism 10. Reference numeral 12 denotes a switching pawl, which is located on the left side of the separation belt drive roller 2 and switches between the first original paper path 1a and the eighth original paper path 1a.

The first document paper bus 1a is formed between the drive roller 2 and the conveyance roller 6, and the eighth document paper path ■ll a
is formed between the paper feed belt drive roller 2, the conveyance roller 6, and the conveyance belt drive roller 7.

Reference numeral 13 denotes a switching claw, which is located on the left side of the conveyor belt drive roller 7, and is used to switch between the fourth document paper path IVa and the sixth document paper path ■Ia.
Switch between The fourth document paper path IVa is formed between the switchback mechanism 9 and the conveyor belt drive roller 7. The sixth original paper path Via is connected to the left roller 6a and the switching claw 13.
is formed between.

14, 15, 16, 17, and 18 are sensors for detecting the leading edge or trailing edge of the manuscript paper in the moving direction, respectively.
is on the left side of the switching claw 13, the sensor 16 is on the lower left side of the switchback mechanism 10, the sensor 17 is on the left side above the roller 6a, and the sensor 18 is on the left side of the conveyor belt drive roller 7. The second manuscript path Ila is the switchback mechanism 9
and the left roller 6a, and the third original paper bus 1ll.
a is formed below the switchback mechanism 9, and furthermore, a fifth document paper path Va and a seventh document paper bus Vlla are formed below the conveyance belt 8, the conveyance roller 6, the switchback mechanism 10, and the paper ejection path, respectively. It is formed between the rollers 11. The lower end of the first manuscript paper bus Ia is divided into a second manuscript paper bus lla and a sixth manuscript paper path Vla,
The lower ends of the sixth original paper path Via and the eighth original paper resistance path vIlla communicate with the fifth original paper path Va. The right end of the third original paper path Ha communicates with the fourth original paper bus and the second original paper path Ifa.

Next, the double-sided copying machine main body B will be explained. Reference numeral 19 denotes a document table glass located below the conveyance belt 8, and the fifth document paper path Va is formed between the conveyance belt 8 and the document table lath 19. Reference numeral 20 denotes a photosensitive drum located below the document table glass 19. 21 is a charger, 22 is a developer,
23 is a transfer charger, and 24 is a cleaner, which are respectively provided on the surface around the photosensitive drum 20. Reference numeral 26 denotes a paper feed roller, which has a disc shape with a cutout at the bottom, and is connected to the photosensitive drum 2.
A paper feed cassette 25 is provided below the paper feed roller 26 on the right side of the paper feed roller 26. A register roller 27 is located between the photosensitive drum 20 and the paper feed cassette 26, and a register roller 27a is pressed against the lower surface of the register roller 27. The front paper feed roller 26 functions to feed out the transfer paper in the paper feed cassette 25 one by one. Reference numeral 28 denotes a conveyor belt for conveying the transferred transfer paper to fixing rollers 29 and 29a. Fixing rollers 29 and 29a are provided on the left side of the transfer paper conveyance belt 28, and the fixing roller 29a is in pressure contact with the lower surface of the fixing roller 29.

30 is a transfer paper guide located on the left side of the fixing rollers 29, 29a, 32 is an intermediate tray located below the photosensitive drum 20, and between the transfer paper conveyance belt 2B and the intermediate tray 32, Four transfer paper conveyance rollers are arranged from left to right, 31, 31', 31'', 31111. A paper refeed roller 33 is provided on the right side of the intermediate tray 3.
Registration stroke 27 of the transfer paper after single-sided transfer entered in 2
, 27a. Reference numerals 34 and 34a denote paper discharge rollers, which are located on the left side of the fixing rollers 29 and 29a, and the paper discharge roller 34 is pressed against the upper surface of the paper discharge roller 34a.

A paper discharge tray 35 is provided on the left side of the paper discharge roller 34a. The paper ejection rollers 34 and 34a transfer the transferred paper to the paper ejection tray 3.
It has the effect of discharging 5. A sensor 36 detects the front end or rear end of the transfer paper in the moving direction, and is located on the upper right side of the intermediate tray. The first transfer paper path Ib is between the paper feed roller 26 and the register roller 27, the second transfer paper path IIL+ is at the upper part of the transfer paper transport roller 28, and the third transfer paper path mb is for fixing. The fourth transfer paper path IVb is between the roller 29a and the transfer paper transport roller 31, the fourth transfer paper path IVb is between the base paper feed roller 33 and the register roller 27a, and the fifth transfer paper path Vb is on the upper surface of the intermediate tray 32. The sixth transfer paper path ``b'' is formed between the transfer paper transport rollers 31 and 31'', and the seventh transfer paper path Vllb is formed between the transfer guide 30 and the paper discharge roller 34. The upper end of the third transfer paper path 111b is connected to the second transfer paper bus Ilb and the seventh transfer paper path 111b.
It communicates with the transfer paper bus 1111b. The lower end of the third transfer paper bus 111b communicates with the sixth transfer paper bus vIb of the sixth transfer paper bus, and the upper end of the fifth transfer paper bus Vb communicates with the sixth transfer paper bus Vl l and the sixth transfer paper bus VIb. The upper end of the fourth transfer paper bus 1b communicates with the first transfer paper bus Ib. Note that the known exposure scanning optical system includes a light source 12a of 8g1, a first mirror 13a1, and a second mirror 13a.
It consists of a mirror 13b, a runes 12b1, a third mirror 13c, and a fourth mirror 13d.

Next, referring to FIGS. 2 and 3, a document separating section to which an embodiment of the present invention is applied will be described.

FIG. 2 is a plan view showing the document separating section. FIG. 3 is a side view showing the document separating section.

In FIGS. 2 and 3, 126, 126 are partition plates, and these partition plates 126, 126 are for separating the original before exposure and the original after exposure.
6 is disposed on both valve sides of the paper feed belts 3, 3. Partition plate arms 127, 127 are pivoted to the left side of the partition plates 126, 126 in the perpendicular direction, respectively, at fulcrums 128, 128. This partition plate 126 pivots in the downward direction of arrow E in FIG. 2 about a fulcrum 128. Further, reference numeral 129 denotes a friction plate, which is sandwiched between a gear 132 that engages with a gear 131 fixed to both ends of the shaft 130 of the separation belt 1 drive a-ra 4 and the partition plate arm 127. The roller 4 and the separation belt driven roller rotate to remove the partition plate 1.
When the paper feed belt 3 comes into contact with the partition plate arm 127
is designed to rotate in the direction G in FIG. This facilitates document feeding from the paper feed tray 1. Further, a roller 133 that receives the load of the partition plate arm 127 via the feed belt 3 is provided on the lower surface of the paper feed belt 3. 136
The bottle shafts 134 and 135 are installed on the partition plate 126.
The hook between the two is a passed spring, and this spring 136 is attached to the fulcrum 1.
It crosses 28. Because of that, the partition plate 1
26 can be rotated in the directions of arrows E and F in FIG. The outer periphery 137 of the partition plate 126 has a cam shape,
When the partition plate 126 rotates in the direction of E in FIG. 2 and the partition plate arm 127 rotates in the direction of arrow G in FIG. 3, the partition plate 126 is rotated in the direction of F in FIG. 'l
l+ 138 is installed perpendicularly below the paper feed belt 3. Reference numeral 139 denotes an optical sensor located below the descending portion of the paper feed belt 3. This optical sensor 139 comes into contact when the partition plate arm 127 rotates in the direction G in FIG.
The rotation of the partition plate arm 127 is detected, and this indicates that the 1f cycle of document copying has been completed. In FIG. 3, 140 is a sensor and the seat path
The sensor is provided on the downstream side of the document and is configured to detect the trailing edge of the document and stop the paper feed belt drive roller and the separation belt driven roller.

Next, the driving section will be explained using FIG. 4.

FIG. 4 is a sectional rear view showing the drive section. In the figure, 141 is a motor, 142 is a motor pulley provided on the motor 141, and this motor pulley 142, a roller 145 coaxial with the paper ejection roller 11a, and a pulley 14.
Belt 143 is in place at 7. Pulley 147 and (
A belt 144 is hung on the general feed row 26. A belt 151 is hooked on a pulley 146 coaxial with the conveyance roller 6 and a boolean 9-153. A pulley is in pressure contact with the pulley 153, and this pulley drives the second switchback mechanism 10. Boo! for driving the first switchback mechanism 9! I-152 is located below the first switchback mechanism 9, and a belt 150 is hooked between the pulley 146 and pulley 152. A clutch 149 is in pressure contact with the separation belt drive roller 4, the paper feed belt drive roller 2, and the boot 9-147, and transmits the power of the motor 141 to the paper feed belt drive roller 2 and the separation belt drive roller 4. . 148 is a clutch;
It is in pressure contact with the motor pulley 142 and the conveyor belt drive roller 7, and switches between forward and reverse rotation of the conveyor belt drive roller 7. Further, as described above, the pulley 146 includes the first switchback mechanism 9 and the second switchback mechanism 1.
Belts 150 and 151 for transmitting power to the boos 9-152 and 153 provided at the motor pulley 142 and the belt 143 are provided.
It is transmitted to the paper ejection rollers lla and 11 via the pulley 145. As described above, it is possible to concentrate the driving portions at - points without having to do so.

Further, the case where the last page of a plurality of original documents is to be fed will be explained with reference to FIGS. 2 and 3. A partition plate 126 is present immediately above the last page. When the last page is fed, the partition plate 126 comes into contact with the paper feed belt 3, so the friction force between the partition plate 126 and the arrow E
direction, and the force of the spring 136 brings it into the state shown by the two-dot chain line in the figure. Here, since a load is applied to the partition plate A127 by the friction plate 129 in the direction of the arrow G,
When the partition plate 126 is folded, it begins to rotate in the G direction. The feeding roller 2 and the separating roller 4 are each provided on the downstream side of the sheet path X and stop when the trailing edge of the document is detected by the sensor 140.
7 stops at the position indicated by the broken line in the figure after rotation when the last page is fed. When the last page is fed, that is, the partition arm 127 is detected by the sensor 139, the last page returns to the paper feed tray 1 after double exposure and is fed until one complete cycle is completed; 2 and the separation belt drive roller 4 are stopped and are set to start rotating at the first sheet of the second cycle, the partition plate 12
6 will be placed on top of the last page.

Next, the operation of the present invention will be described with reference to FIG. 1, in which a double-sided copy is obtained from a double-sided original. Introduction,
When the mode for double-sided copying from a double-sided original is selected using the operation panel (not shown) on the main body, the automatic circulating double-sided original feeding device A
The switching claw 12 is on the first document paper path Ia side, and the other switching claw 13 is on the fourth document paper path IVa-Ijl! Set to I. The originals set on the paper feed tray 1 are separated one by one from the bottom by a paper feed belt 3 and a separation belt 5.
Since the switching claw 12 is on the side of the first original paper path Ia, it passes through Ml, the second original paper paths la and lla, and enters the third original paper path I[a]. Here, when the sensor 14 detects the rear end of the original in the moving direction, the first switchback mechanism 9 is switched and the original is transferred to the fourth and fifth original paper paths JVa.
, Va, and the original is placed on the original paper tray 19 in a book with the lower side of the original in the paper feed tray 1 facing downward.
y will be done. At this time, the stopping position of the document is determined by the sensor 18 detecting the rear end of the document in the moving direction and by a preset clock signal.

When the original is placed on the original paper table 19, the copying operation of the double-sided copying machine main body B starts, and the transfer paper is fed from the cassette 25 by the paper feed roller. . At this time, the transfer paper guide 30 is switched to the third transfer paper path mb. The fed transfer paper passes through the first transfer paper path Ib, one side of which is transferred, and then passes through the second transfer paper path Ilb.
and is fixed by fixing rollers 29 and 29a. Since the transfer paper guide 30 is on the side of the third transfer paper path b, the transfer paper after fixing one side is placed in the third, sixth, and fifth transfer paper paths.
The transfer paper bus 111b passes through 1b and Vb and enters the intermediate tray 32 with the transferred side facing up.

On the other hand, the original that has been exposed on one side is ejected from the original paper table glass 19''2, but since the switch 13 is switched to the sixth original paper bus VIa side by the single-sided exposure end signal, the sixth original Passing the paper bus VIa, the eighth manuscript paper bus Vllll
Enter a. The rear end of the original +114 in the moving direction is sensor 1.
6 is detected, the second switchback mechanism 10 switches, passes through the manuscript paper bus Ha of the edict 2, and passes the manuscript paper bus 11 of the edict 2.
Enter 1a. Similarly to the above, when the sensor 14 detects the rear end of the document in the moving direction, the first switchback mechanism 9 is switched. At the same time, the switching claw 13 also switches to the fourth original paper path I.
Switching to the Va side, the fourth and fifth manuscript paper paths IVa and V
The original is conveyed along the original paper plate 19 and placed on the original paper table 19 again.

At this time, the side of the original opposite to the side that was previously copied is facing down on the original paper table 19.

When the original is placed on the original table again on the lath 19, the copying operation of the double-sided copying machine main body B starts, and when the transfer paper on which one-sided transfer has been completed in the intermediate tray 32 is re-fed by the re-feed O-ra 33, At the same time, the transfer paper guide 30 is switched to the seventh transfer paper path (2b). The re-fed transfer paper is transferred to the fourth transfer paper path Ivb.
After passing through, the paper passes through the first transfer paper path Ib with the untransferred side facing up, completing the double-sided transfer. After that, after passing through the second transfer paper path nb, the fixing roller 29°2
It is fixed at 9a. Since the transfer paper guide 30 is on the side of the seventh transfer paper path (b), after the duplex copying of the transfer paper is completed, the transfer paper passes through the seventh transfer paper path Wlb and is ejected to the paper a.
- The paper is discharged onto the paper discharge tray 35 by the rollers 34, 34a. At this time, the transfer paper is ejected with the side that was later copied facing up.

The original paper that has been exposed on both sides is ejected from the original paper table on the lath 19, but the switching pawl 13 is switched again to the sixth original paper bus vIa side in response to the end signal of the double-sided exposure. The eighth manuscript paper bus Wit passes through the manuscript paper bus v1a.
Enter a. Now move the manuscript paper.

When the rear end in the direction is detected by the sensor 17, feeding of the next document sheet, that is, the lowest document sheet in the paper feed tray 1 is started. By repeating the above operation for the number of sheets of original paper set on the paper feed tray, double-sided copies of the double-sided originals are placed on the output tray 35 in the same page order as one set of originals. This completes one cycle.

The original paper that has entered the eighth original paper bus Vlla is delivered to the paper output roller 11. lla, the paper is returned to the top of the paper feed tray 1 with the same side facing up as before.

By entering the desired number of sets on the operation unit (not shown), the number of cycles is repeated the same number of times as the number of sets, and the desired number of sets of double-sided copies in the same page order as the original are placed on the paper output tray 35. This means that the originals are placed on the paper feed tray 1 in the same page order as before copying.

Next, the operation of obtaining a double-sided copy from a single-sided original will be explained.

When the mode for duplex copying from a single-sided original is selected using the operation unit (not shown) on the main body, the automatic circulating double-sided original feeding device A
The switching claw 12 is on the side of the 3gs original paper bus ■a.
3 is set on the sixth original paper bus VIa.

The original paper set on the paper feed tray 1 with the side to be copied facing upward is separated one by one from the bottom, passes through the eighth original paper bus Vlia, and is placed on the original paper base glass 19 with the side to be copied facing downward. It is placed on the table.

When the original paper is placed on the original paper table 19, the copying operation of the double-sided copying machine main body B starts, and the transfer paper is fed from the paper feed cassette 25 by the paper feed roller 26. At this time, the transfer paper guide 30 is switched to the third original paper bus IIIa.

The fed transfer paper passes through the first original paper bus 1b and is transferred to the second, third, sixth, and fifth original paper buses flb.
, n+b, VIb, and Vb, and enters the intermediate tray 32 with its transferred side facing upward.

The original after exposure is transferred to the sixth and seventh original paper buses Via.

(2) The paper passes through a and is returned to the top of the paper feed tray 1 with the same side facing up as before. Here, when the rear end of the document sheet in the moving direction is detected by the sensor 17, feeding of the next document sheet, that is, the document at the bottom of the paper feed tray 1 is started. When the second sheet of original paper is placed on the original sheet glass 19 in the same way as the original sheet described above, the copying operation of the double-sided copying machine main body B starts, and the paper re-feeding roller 33 transfers the second sheet of paper to the intermediate tray 32.
At the same time as re-feeding the transfer paper on which one-sided transfer has been completed, the transfer paper guide 30 switches to the seventh transfer paper path Vllb. After the re-fed transfer paper passes through the fourth transfer paper path Ivb,
Place the first document paper bus I with the untransferred side facing up.
After passing through b, double-sided transfer is completed.

After that, it passes through the second and seventh transfer paper paths Ilb+■b,
The paper is ejected onto the paper ejection tray 35 with the side copied later facing up.

The original after exposure is returned to the top of the paper feed tray 1 with the same side facing up as before being fed, in the same manner as the first original.

By repeating the above operation for the number of originals set in paper feed tray 1, double-sided copies of the single-sided originals are placed on the paper output tray in the same order as one set of originals. The cycle ends.

By entering the desired number of sets on an operation unit (not shown), the cycle is repeated the same number of times as the number of sets, and the desired number of double-sided copy sets with the same page order as the original are obtained on the paper output tray 35. Further, the originals are placed on the paper feed tray 1 in the same page order as before copying.

Next, a method for obtaining a one-sided copy from a one-sided original will be explained.

When the mode of single-sided copying from a single-sided original is selected using an operation unit on the main body (not shown), the switching claw 12 of the circulating double-sided automatic document feeding device A is moved to the eighth original paper bus Wlla side.
3 is set on the sixth original paper path vIa side.

The operation until the manuscript paper table is placed on the lath 19 is the same as when making a double-sided copy from a single-sided manuscript, and the transfer paper fed from the paper feed cassette 25 is , seventh transfer paper path Ib, Ilb, and N, and is ejected onto the ejection tray 35 with the transferred side facing upward. At this time, the transfer paper guide 3o remains on the seventh transfer paper bus (b) side. The original paper after exposure is passed through the sixth and seventh original paper passes Vf'a'.

The paper passes through Vlla and returns to the top of the paper feed tray 1 with the same side facing up as before it was fed. Here, when the rear end of the original paper in the moving direction is detected by the sensor 17, the next original
In other words, feeding of the document at the bottom of the paper feeding tray is started.

By repeating the above operation for the number of originals set in the paper feed tray 1, a double-sided copy of the single-sided original with the same page order as one set of originals is placed on the paper output tray 35. One cycle ends.

By entering the desired number of sets on the operation unit (not shown), the cycle is repeated the same number of times as the number of sets, and the desired number of single-sided copy sets with the same page order as the originals are obtained on the paper output tray 35. , and the originals are placed on the paper feed tray 1 in the same page order as before copying.

Next, the operation of obtaining a single-sided copy from a double-sided original will be explained.

When the mode of single-sided copying from a double-sided original is selected using the operation unit (not shown) on the main body, the automatic circulating double-sided original feeding device A
The switching claw 12 is located on the first original paper bus Ia side, and the switching claw 13 is located on the side of the first original paper bus Ia.
is set on the fourth document paper path Iva side. The originals set on the paper feed tray 1 with the first page facing upward are separated one by one from the bottom by the paper feed belt 3 and separation belt 5, and the switching claw 12 is placed on the side of the first original paper bus Ia. Therefore, the first and second manuscript paper passes I a and II
a and enters the third manuscript paper path lla. here,
When the sensor 14 detects the trailing edge of the manuscript paper in the moving direction,
The first switchback mechanism 9 is switched, the document paper is conveyed through the fourth and fifth passes Iva and Va, and the document paper table is moved to the last one.
The original paper is placed on the paper feed tray 1 with its bottom side facing down. At this time, the stopping position of the original paper is determined by the sensor 1B detecting the rear end of the original paper in the moving direction and based on a preset clock number. When the original paper is placed on the original paper stand on the lath 19, the copying operation of the double-sided copying machine main body B starts,
Transfer paper is fed from inside the paper feed cassette 25 by a paper feed roller 26 . The fed transfer paper is transferred to the first original paper path I.
After passing through path Ilb, the image is transferred, passes through second document paper path Ilb, and is fixed by fixing rollers 29 and 29a. Since the transfer paper guide 30 is on the seventh transfer paper path (1) side, the paper is ejected with the surface transferred onto the paper ejection tray 35 facing upward. On the other hand, the original that has been exposed on one side is ejected from the original paper table from above the lath 19, but the switching claw 13 is switched to the sixth original paper path 6 side in response to the single-sided exposure completion signal. , passes through the sixth manuscript paper path Vfa and passes through the eighth manuscript paper path ■a
to go into. When the trailing edge sensor 16 in the moving direction of the original paper detects the detection, the second switchback mechanism 10 switches and the second
passes through the original paper path [Ia and enters the third original paper path lna. Similarly to the above, when the sensor 14 detects the rear end of the original paper in the moving direction, the first switchback mechanism 9 is switched. At the same time, the switching claw 13 also switches to the fourth original paper path I.
Switching to the Va side, the fourth and fifth manuscript paper paths IVa and V
The originals are conveyed in the order of a and placed on the original paper table glass 19 again. At this time, the side of the original paper that was copied first is
The other side is facing down.

When the document table is placed on the lath 19 again, the copying operation of the double-sided copying machine body B starts, and the transfer paper is fed from the paper feed cassette 25 by the paper feed roller 26 . The fed transfer paper passes through the first, second, and third transfer paper paths 1bAIb similarly to the transfer paper described above.

(2) The paper passes through b and is ejected onto the paper ejection tray 1 with the transferred side facing up.

The original paper that has been exposed on both sides is ejected from the original paper table glass 19, but the switching claw 13 is switched to the sixth original paper path vIa side by the end signal of the double-sided exposure. 6 manuscript paper bus Vlila and enters the eighth manuscript paper bus Vlila. Here, when the rear end of the document sheet in the moving direction is detected by the sensor 17, feeding of the next document sheet, that is, the lowest document sheet of feed 1-ray 1 is started. The original) l-I4 paper that entered the 8th manuscript paper no. lla, the paper is returned to the top of the paper feed tray 1 with the same side facing up as before.

By repeating the above operations as many times as the number of sheets of original paper set on paper feed tray 1, one sheet of paper from both sides of the original is printed.
A single-sided copy with the same page order as the original set is placed in the output tray 35.
1 cycle is completed.

By entering the desired number of sets on an operation unit (not shown), the cycle is repeated the same number of times as the number of sets, and the desired number of double-sided copy sets with the same page order as the original are obtained on the paper output tray 35. Furthermore, the originals are placed on the paper feed tray 1 in the same page order as before copying.

As explained above, according to the double-sided copying method of the present invention,
It is now possible to automatically and reliably perform double-sided copying from sheet originals, especially double-sided sheet originals, and the page order before and after copying of the original is not changed at all, and after copying is complete, the paper is ejected. Since the transfer sheets discharged onto the tray are also stacked in the same page order as the originals, subsequent processing is extremely simple.

Further, since copying is started from the first page or the first page from the end of the original, there is no need to turn over the transfer paper again after double-sided copying, and the main body mechanism can be simplified.

In addition, when obtaining a single-sided copy from a double-sided original, the original path is shortened to start copying from the first page from the end, resulting in less damage to the original, shorter original replacement time, and faster copying operations. It also has the effect of increasing compatibility.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention, FIG. 2 is a plan view showing details of the separating section, FIG. 3 is a detailed side view of the RIB section, and FIG. 4 is a detailed view of the driving section. It is a rear view side view of the cross section shown. 1...Paper feed tray, 2...Paper feed belt drive roller,
2a... Paper feed belt driven roller, 3... Paper feed belt, 4... Separation belt drive roller, 4a... Separation belt driven roller, 5... Separation belt, 6... Conveyance roller, 6a...Left roller, 6b...Right roller, 7...Transportation belt drive roller, 7a...Transportation belt driven roller, 8...4 feeding belt, 9...First switchback rock structure , 10... second switchback mechanism, 11. ll
a... Paper ejection roller, 12.13...Switching claw, 14.
i5. te, 1y, ts...Sensor, 19...Original paper table glass, 20...Photosensitive drum, 21...Charger, 22...Developer, 23...Transfer charger, 24...
・Cleaner, 25...Paper feed cassette, 26...Paper feed roller, 27.27a...Register [Cola, 28
...Transfer paper conveyance belt, 29.29a...Fixing roller, 30...Transfer paper guide, 31.31', 31"3
1111... Transfer paper conveyance roller, 32... Intermediate tray, 33... Paper refeed roller, 34. 34a... Paper discharge roller, 35... Paper discharge tray, 12a... Light source, 1
2b... Lens, 13a... First mirror, 13b.
...Second mirror, 13c...Third mirror, 13d...
・Fourth mirror, 126... Partition plate, 127... Partition plate arm, 128... Fulcrum, 129... Friction plate, 1
30...shaft, 131,132...gear, 133.
...Roller, 134, 135...Pin shaft, 136...
・Pi 1.137...Outer circumference, 138...Axis, 139
...Light sensor-, 140...Sensor, 141...
・Motor, 142... Motor pulley, 143, 14
4... Belt, 145... Roller, 146, 147
...Pulley, 148,149...Clutch, 15
0,151...Belt, 152,153...Pulley, Ia, la, 111a, ■a, Va, Via, M
la, 1n111a -4g 1, @
2, third, fourth, fifth, sixth, seventh, eighth manuscript paper bus, Ib#Ilb, n1bjlVb, Vb, Vlb,
)'llb, Vlllb-iL 2nd, 3rd, 4th, 5th, 6th, 7th, 8th transfer paper bus, A... Circulating type double-sided document distance feeding device, B... Both sides Copy machine, X... Sheet bus patent applicant Canon Co., Ltd.

Claims (4)

[Claims] (1) Separate and transport the originals one by one from the bottom of the original, feed them to the original table, and after exposure, return the originals and eject them to the same side as when they were inserted. In a circulation type document feeding device, sheet-like documents are stacked and set, and the document is fed one by one from the bottom of the stacked documents to the document table for copying. After copying the first page from the end or one page of the original starting from the end, the original and copy paper are single-sided,
After each copy is reversed and the back side has been copied, the original is reversed again and returned to the top of the stack with the later copied side facing up. A double-sided copying method using double-sided originals, which is characterized by stacking the originals with the printed side facing up. (2) The original is set with the first page facing upward, copying is started from the first page from the end, and each original is fed to the original table while being reversed.
Double-sided copying method using double-sided originals as described in Section 2. (3) The original is set with the first page facing down, copying is started from the first page, and each original is fed to the original table while being reversed. Double-sided copying method using double-sided originals. (4) Assuming that one cycle is the completion of double-sided copying for the number of stacked originals set in a stack, one cycle can be repeated as many times as necessary. Double-sided copying method using double-sided originals.