JPH0217466B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sheet document conveying device, and more particularly, to a sheet document conveying device, which separates and feeds sheet documents (manuscript paper) one by one, guides them to a predetermined position, and then discharges the sheet documents from the predetermined position. The present invention relates to a sheet document conveying device that turns a sheet document upside down and guides it to a predetermined position again.

Traditionally, this type of device has been used, for example, to store multiple pages of original paper in a supply tray placed above an exposed platen on the outside of a copier for originals, with the last page at the bottom. The manuscript sheets are stacked and supported in the page order such that the side to be copied faces upward, and the bottom manuscript paper of the stacked plurality of manuscript papers is repeatedly pulled out, and the manuscript is The paper was configured to form a generally closed loop from the bottom of the supply tray through the exposed platen and back to the top of the supply tray. However, this configuration has the disadvantage that the drive units must be distributed throughout the device because it constitutes a closed loop.

In addition, an apparatus that performs double-sided copying using a circulation method sequentially copies one side of the original paper onto each side of copy paper (transfer paper), and stores the resulting single-sided copy paper in an intermediate tray.
The method used was to refeed the paper from there and copy it sequentially to the back side. For this reason, if a copy paper jam occurs during copy paper, the page order will be distorted, so all copy paper left in the intermediate tray after one-sided copying and after double-sided copying are discarded and There was the inconvenience of having to redo the process.

In order to eliminate this drawback, conventionally, a method has been devised to obtain double-sided copy paper by reversing the front and back sides of each document sheet by performing double-sided copying using a circulation method.

This device is equipped with a document conveying device that reverses the document paper from the stacking table and guides it to a predetermined position, and starts copying from the second page or the second page from the end of the document paper, and makes double-sided copies. After finishing, the copy paper as well as the original paper are turned over again and stacked on the paper discharge tray with the later copied side facing down to obtain double-sided copy paper with the same page order as the original paper.

However, according to this method, the first
Copying cannot be started from the first page or from the end, and the copy paper must be reversed after double-sided copying to obtain the same page order as the original paper, making the mechanism unavoidable. Ta.

The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and is a novel sheet that has a simple structure, can be made smaller and lighter, and can also lead sheet originals to a predetermined position in the same front and back state as when stacked. The purpose of the present invention is to provide a document conveying device.

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

FIG. 1 is a sectional view of an embodiment of the present invention,
Each element and the passage of original paper and transfer paper (copy paper) are shown.

In FIG. 1, A is a circulating double-sided automatic document feeder, and B is a double-sided copying machine main body for making double-sided copies. Reference numeral 1 denotes a paper feed tray serving as a loading means, which is tilted downward to the left side. This paper feed tray 1 can stack a plurality of original papers (sheet originals). A paper feed belt driven roller 2a is provided adjacent to the left side of the paper feed tray 1, a paper feed belt 3 is wound around this paper feed belt driven roller 2a, and a paper feed belt driving roller 2 is attached to the other end of the paper feed belt 3. Install. The paper feed belt 3 is wound around a paper feed belt driven roller 2a and a paper feed belt drive roller 2 to rotate in the direction of arrow C. Paper feed belt drive roller 2
and the paper feed belt driven roller 2a is the paper feed belt 3
It is designed to rotate in the same direction (direction of arrow C). 4 is a separation belt drive roller, and 4a is a separation belt driven roller, both of which are arranged in a row above the paper feed belt drive roller 2, and these two rollers, that is, the separation belt drive roller 4 and the separation belt driven roller A separation belt 5 is wound around 4a, and this separation belt 5 is configured to rotate in the direction of arrow D. In this way, between the separating belt 5 and the paper feed belt 3, one sheet of document paper placed on the paper feed tray 1 is separated from the bottom. Reference numeral 6 denotes a conveyance roller located on the lower left side of the paper feed belt driving roller 2, and two rollers 6b and 6a are pressed against both left and right sides of the conveyance roller 6. 7
A conveyance belt drive roller 7 is located below the paper feed belt drive roller 2, and this conveyance 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. Then, the conveyor belt driven roller 7
A is located at the right end of the double-sided automatic document feeder A. 9
and 10 are each a first switchback mechanism;
The first switchback mechanism 9 is located at the lower left of the left roller 6b, and the switchback mechanism 10 is located at the lower left of the left roller 6b.
It is on the upper left of a. 11 and 11a are paper discharge rollers located above the separation belt drive roller 4;
The paper discharge roller 11 and the paper discharge roller 11a are arranged vertically and pressed against each other. These paper ejection rollers 11a and 11 transfer the original paper after copying to the paper feed tray 1.
Drain upwards. The conveyance force of the paper discharge rollers 11a, 11 is made weaker than the conveyance force of the second switchback mechanism 10. A switching pawl 12 is located on the left side of the paper feed belt drive roller 2, and is used to switch between the first original paper path a and the eighth original paper path a. The first document paper path a is formed between the paper feed belt drive roller 2 and the transport roller 6, and the eighth document paper path a is formed between the paper feed belt drive roller 2, the transport roller 6, and the transport belt drive roller 7. is formed. Reference numeral 13 denotes a switching pawl, which is located on the left side of the conveyor belt drive roller 7 and switches between the fourth document paper path a and the sixth document paper path a. The fourth document paper path a is formed between the first switchback mechanism 9 and the conveyor belt drive roller 7. The sixth document paper path a is formed between the left roller 6a and the switching pawl 13. 14, 15, 16, 17, and 18 are sensors for detecting the leading edge or the trailing edge of the original paper in the moving direction, respectively; the sensor 14 is on the right side of the first switchback mechanism 9, the sensor 15 is on the left side of the switching claw 13, The sensor 16 is the second switchback mechanism 1
0, the sensor 17 is above the left roller 6a, and the sensor 18 is above the conveyor belt drive roller 7.
on the left side. The second document paper path a is between the first switchback mechanism 9 and the left roller 6a, and the third document paper path a is between the first switchback mechanism 9 and the left roller 6a.
Further, a fifth document paper path a and a seventh document paper path a are formed below the conveyance belt 8 and between the conveyance roller 6, the second switchback mechanism 10, and the paper discharge roller 11, respectively. has been done. Then, the lower end of the first document paper path a is
It is divided into a document paper path a and a sixth document paper path a, and the lower end of the sixth document paper path a and the lower end of the eighth document paper path a communicate with the left end of the fifth document paper path a. The right end of the third manuscript paper path a is the fourth
It communicates with the original paper path a and the second original paper path a.

Next, the double-sided copying machine main body B will be explained. 1
Reference numeral 9 denotes a document paper base glass, which is located below the conveyor belt 8 , and a fifth document paper path a is formed between the conveyor belt 8 and the document paper base glass 19 . Reference numeral 20 denotes a photosensitive drum, which is located below the document paper base glass 19. 21 is a charger, 22 is a developer, 23 is a transfer charger, and 24 is a cleaner, all of which are arranged around the photosensitive drum 20. Reference numeral 26 denotes a paper feed roller, which has a partially cut-out disc shape and is located on the right side of the photosensitive drum 20. Below the paper feed roller 26, a paper feed cassette 25 is provided. 27 is a register roller, which connects the photosensitive drum 20 and the paper feed cassette 25.
The register roller 27a is in pressure contact with the lower surface of the register roller 27. The 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 transfer paper conveyance belt that conveys the transfer paper after transfer to fixing rollers 29 and 29a, and this transfer paper conveyance belt 28 is arranged in a row on the left side of the photosensitive drum 20. There are fixing rollers 29a, 29a on the left side of the transfer paper conveyance belt 28,
A 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 28 and the intermediate tray 32,
Four transfer paper conveyance rollers 31, 31', 31'', 3
1 are arranged from left to right. The intermediate tray 32 is arranged so as to descend toward the left side, and a paper refeed roller 33 is provided on the right side of the intermediate tray 32. It functions to feed the subsequent transfer paper to the register rollers 27, 27a. 3
4, 34a are paper ejection rollers, and fixing rollers 29, 29
a, and the paper ejection roller 34 is on the left side of the paper ejection roller 3.
It is pressed against the upper surface of 4a. Paper ejection roller 34a
There is a paper discharge tray 35 on the left side. Paper ejection roller 3
4 and 34a function to discharge the transfer paper after transfer to the paper discharge tray 35. 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 32. On the other hand, the first transfer paper path b includes the paper feed roller 26 and the register roller 27.
The second transfer paper path b is located above the transfer paper transport rollers 31, 31', 31'', 31,
The transfer paper path b is between the fixing roller 29a and the transfer paper transport roller 31, and the fourth transfer paper path b is between the paper refeed roller 33 and the register roller 27a.
The fifth transfer paper bus b is placed on the upper surface of the intermediate tray 32,
The sixth transfer paper path b is the transfer paper transport rollers 31 and 3.
1, and a seventh transfer paper path b is formed between the transfer paper guide 30 and the paper discharge roller 34, respectively. The upper end of the third transfer paper path b communicates with the second transfer paper path b and the seventh transfer paper path b. The lower end of the third transfer paper path b communicates with the sixth transfer paper path b, the upper end of the fifth transfer paper path b communicates with the sixth transfer paper path b and the fourth transfer paper path b, and the fourth transfer paper path b communicates with the fourth transfer paper path b. The upper end of path b communicates with first transfer paper path b. The known exposure scanning optical system includes a light source 12a, a first mirror 13a, a second mirror 13b, a lens 12b, a third mirror 13c, and a fourth mirror 13d.

Next, with reference to FIGS. 2 and 3, a description will be given of a document separation section which is separation and feeding means to which an embodiment of the present invention is applied.

FIG. 2 is a plan view showing the document separating section. Third
The figure is a side view showing the document separating section.

In Figures 2 and 3, 126, 126
is a partition plate, and this pair of partition plates 126, 12
Reference numeral 6 separates the original paper before exposure and the original paper after exposure, and partition plates 126, 126 are disposed on both outer sides of the pair of paper feed belts 3, 3. Partition plate arms 127, 127 are placed at fulcrums 128, 12 on the left side in a direction perpendicular to these partition plates 126, 126, respectively.
Attach the shaft at 8. This partition plate 126 has a fulcrum 128
It is rotatable in the direction of arrow E in FIG. 2 about . Further, reference numeral 129 is a friction plate, which is connected to a gear 132 that engages with a gear 131 fixed to both ends of the shaft 130 of the separation belt drive roller 4 and the partition plate arm 1.
27, and when the separation belt drive roller 4 and the separation belt driven roller 4a rotate and the paper feed belt 3 comes into contact with the partition plate 126, the partition plate arm 127 moves in the direction of arrow G in FIG. It is designed to rotate in the direction. This facilitates the feeding of original paper from the paper feed tray 1. Further, a roller 133 that receives the load of the partition plate arm 127 via the paper feed belt 3 is provided on the lower surface of the paper feed belt 3. 13
6 is a pin shaft 134 erected on the partition plate 126;
135, this spring 136
crosses the fulcrum 128. Due to this,
The partition plate 126 can rotate in the directions of arrows E and F in FIG. The outer periphery 137 of the partition plate 126 is shaped like a cam, and when the partition plate 126 rotates in the direction of arrow E in FIG. 2 and the partition plate arm 127 rotates in the direction of arrow G in FIG. The shaft 138 is moved so as to return the plate 126 in the direction of arrow F in FIG.
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 detects the rotation of the partition plate arm 127 when the partition plate arm 127 rotates in the direction of arrow G in FIG. 3, thereby indicating that one cycle of document copying has been completed. It is something. In FIG. 3, 140 is a sensor provided on the downstream side of the sheet path
Detects the trailing edge of the original paper and drives the paper feed belt drive roller 2.
And the separation belt driving roller 4 is stopped.

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 a belt 143 is hooked around the motor pulley 142, and a pulley 145 and a pulley 147 that are coaxial with the paper discharge roller 11a. A belt 144 is wrapped around the pulley 147 and the conveyance roller 6. A belt 151 is placed around a pulley 146 and a pulley 153 that are coaxial with the conveyance roller 6. A pulley is pressed against the pulley 153, and this pulley drives the second switchback mechanism 10. A pulley 152 for driving the first switchback mechanism 9 is a pulley 152 for driving the first switchback mechanism 9.
Located below the switchback mechanism 9, the pulley 1
A belt 150 is placed between the pulley 152 and the 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 pulley 147, respectively, and transmits the power of the motor 141 to the paper feed belt drive roller 2 and the separation belt drive roller 4. A clutch 148 is pressed against the motor pulley 142 and the conveyor belt drive roller 7, and switches the conveyor belt drive roller 7 between forward and reverse rotation. Furthermore, as described above, the pulley 146 is provided with the first switchback mechanism 9 and the second switchback mechanism 10.
Belts 150 and 151 for transmitting power to pulleys 152 and 153 provided in the
42, a belt 143, and a pulley 145, and are transmitted to the paper discharge rollers 11a and 11. As described above, it is possible to concentrate the driving parts in one place without separating them.

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

Next, the operation of this embodiment will be described with reference to FIG. 1, in which double-sided copy paper is obtained from double-sided original paper. First, when the mode from double-sided original paper to double-sided copy paper is selected using the operation unit on the main body (not shown), the switching claw 12 of the circulating double-sided automatic document feeding device The switching claw 13 is set on the fourth original paper path a side. The document sheets set on the paper feed tray 1 are separated one by one from the bottom by the paper feed belt 3 and separation belt 5, and since the switching claw 12 is on the side of the first document path a, 1. Second manuscript paper path a,
a and enters the third document paper path a. Here, when the sensor 14 detects the rear end of the original paper in the moving direction, the first switchback mechanism 9 is switched, the original paper is conveyed through the fourth and fifth original paper paths a, a, and the original paper table glass 19 The manuscript paper is placed on top, that is, in a predetermined position, with the bottom surface of the paper feed tray 1 facing downward. At this time, the stopping position of the original paper is determined by a sensor 18 that detects the rear end of the original paper in the moving direction and based on a preset clock signal.

When the original paper is placed on the original paper table glass 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 transfer paper path b side. The fed transfer paper passes through the first transfer paper path b, one side of which is transferred, and passes through the second transfer paper path b to the fixing roller 29,
It is fixed by 29a. Since the transfer paper guide 30 is on the third transfer paper path b side, the transfer paper after fixing one side is transferred to the intermediate tray 32 through the third, sixth and fifth transfer paper passes b, b and b. Enter with the side facing up.

On the other hand, the original paper that has been exposed on one side is ejected from the original paper base glass 19, that is, from a predetermined position.
The switching claw 13 switches to the sixth position in response to the one-sided exposure end signal.
In order to switch to the original paper path a side, it passes through the sixth original paper path a and enters the seventh original paper path a. When the sensor 16 detects the rear end of the original paper in the moving direction, the second switchback mechanism 10 is switched, and the original paper passes through the second original paper path a and enters the third original paper path a. Similarly to the above, when the sensor 14 detects the trailing edge of the original paper in the moving direction, the first switchback mechanism 9 is switched. At the same time, the switching claw 13 is also switched to the fourth document paper path a side, so that the document paper is conveyed through the fourth and fifth document paper paths a and a and placed again on the document paper table glass 19, that is, at a predetermined position. be done. At this time, the side of the original paper opposite to the side on which the copy was made is facing down on the original paper table glass 19.

When the original paper is placed on the original paper table glass 19 again, the copying operation of the double-sided copying machine main body B starts, and the re-feeding roller 33 refeeds the transfer paper in the intermediate tray 32 on which one-sided transfer has been completed. At the same time as the paper is transferred, the transfer paper guide 30 is switched to the seventh transfer paper path b. After passing through the fourth transfer paper path b, the re-fed transfer paper passes through the first transfer paper pass b with the untransferred side facing up, completing the double-sided transfer. Thereafter, the transfer paper passes through a second transfer paper path b, and is then fixed by fixing rollers 29, 29a. Since the transfer paper guide 30 is on the side of the seventh transfer paper path b, the transfer paper after double-sided copying passes through the seventh transfer paper path b and is placed on the paper ejection tray 35 by the paper ejection rollers 34 and 34a. Paper is ejected. At this time, the transfer paper is ejected with the side copied later facing up.

After double-sided exposure, the manuscript paper is placed on the manuscript paper base glass 1.
9, that is, from a predetermined position, the switching claw 13 is switched again to the 6th original paper path a side by the double-sided exposure end signal, so that the original paper passes through the 6th original paper path a and is ejected from the 7th original. Enter paper pass a.
When the rear end of the original paper in the moving direction is detected by the sensor 17, feeding of the next original paper, that is, the lowest original paper 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 1, double-sided copy paper with the same page order as one set of original papers is placed on the paper output tray 35 from the double-sided original paper. 1 cycle is completed.

The original paper that has entered the seventh original paper path a is returned by paper discharge rollers 11 and 11a with the same side facing up as before being fed to the top of the paper feed tray 1.

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 double-sided copy paper is set on the paper output tray 35 in the same page order as the original paper. The set number of pages is obtained, and the original sheets are placed on the paper feed tray 1 in the same page order as before copying.

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

When the mode from single-sided original paper to double-sided copy paper is selected using the operation unit (not shown) on the main body, the switching claw 12 of the circulating double-sided automatic document feeding device A is moved to the eighth original paper path a side, and the switching claw 13 is moved to the eighth original paper path a side. 6th manuscript paper pass a
is set to

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.
The document passes through the eighth document path a and the fifth document path a, and is placed on the document table glass 19, that is, at a predetermined position, with the side to be copied facing downward.

When the document paper is placed on the document table glass 19, 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. At this time, the transfer paper guide 30 is switched to the third transfer paper path b. The fed transfer paper passes through the first transfer paper path b, is transferred on one side, and then passes through the second, third, sixth, fifth transfer paper passes b, b,
b, b, and enters the intermediate tray 32 with the surface transferred to it facing up.

After the exposure, the original paper passes through the sixth and seventh original paper passes a and a and is returned to the top of the paper feed tray 1 with the same side facing up. Here, when the rear end of the document paper in the moving direction is detected by the sensor 17, the next document paper, that is, the paper feed tray 1 is detected.
Feeding of the document sheet at the bottom of the screen starts. Similar to the above manuscript paper, the second manuscript paper is placed on the manuscript paper base glass 1.
9, the copying operation of the double-sided copying machine body B starts, and the re-feeding roller 33 re-feeds the transfer paper on which one-sided transfer has been completed in the intermediate tray 32, and at the same time, the transfer paper guide 30 is the 7th transfer paper path b
Switch to . After passing through the fourth transfer paper path b, the re-fed transfer paper passes through the first transfer paper pass b with the untransferred side facing up, completing the double-sided transfer. Thereafter, the transfer paper passes through the second and seventh transfer paper paths b and b, and is ejected onto the paper ejection tray 35 with the later copied side facing upward.

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

By repeating the above operation for the number of sheets of original paper set in paper feed tray 1, double-sided copy papers are placed on the output tray in the same order as the original papers in one set, starting with the single-sided original paper. becomes 1
The 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 sets of double-sided copy paper in the same page order as the original paper are placed on the paper output tray 35. obtained,
Also, the original sheets are placed on the paper feed tray 1 in the same page order as before copying.

Next, the operation of obtaining single-sided copy paper from single-sided original paper will be described.

When the mode from single-sided original paper to single-sided copy paper is selected using the 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 path a side, and the switching claw 13 is moved to the eighth original paper path a side. 6th manuscript paper pass a
It is set on the side.

The operation until the original paper is placed on the original paper table glass 19 is the same as when obtaining double-sided copy paper from single-sided original paper, and the transfer paper fed from the paper feed cassette 25 is , second and seventh transfer paper paths b, b, b, and are ejected onto the ejection tray 35 with the transferred side facing upward. At this time, the transfer paper guide 30 remains on the seventh transfer paper path b side. After the exposure, the original paper passes through the sixth and seventh original paper paths a and a and is returned to the top of the paper feed tray 1 with the same side facing up as before being fed. Here, the rear edge of the manuscript paper in the direction of movement is sensor 1.
7, the feeding of the next document sheet, that is, the document sheet at the bottom of the paper feed tray 1 is started.

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

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

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

When the mode from double-sided original paper to single-sided copy paper is selected using the 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 first original paper path a side, and the switching claw 13 is moved to the first original paper path a side. 4th manuscript paper path a
It is set on the side. The original paper set with the first page facing upward on the paper feed tray 1 is separated one by one from the bottom by the paper feed belt 3 and separation belt 5.
Since the switching claw 12 is on the side of the first original paper path a, the original paper is transferred to the first and second original paper paths a,
a and enters the third document paper path a. Here, when the sensor 14 detects the rear end of the original paper in the moving direction, the first switchback mechanism 9 is switched, and the original paper is conveyed through the fourth and fifth passes a and a, and is placed on the original paper table glass 19, that is, at a predetermined position. The document paper is placed in the same position as if it were placed with its bottom side facing down in the paper feed tray 1. At this time, the stopping position of the original paper is determined by a sensor 18 that detects the rear end of the original paper in the moving direction and based on a preset clock signal. When the document paper is placed on the document table glass 19, 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 a first transfer paper path b, is transferred, passes through a second transfer paper path b, and is fixed by fixing rollers 29 and 29a. Since the transfer paper guide 30 is located on the seventh transfer paper path b side, the transfer paper is ejected onto the paper ejection tray 35 with the transferred side facing upward. On the other hand, the original paper that has been exposed on one side is ejected from the original paper base glass 19, that is, from a predetermined position, but in response to the single-sided exposure end signal, the switching claw 13 moves the original paper to the sixth original paper path a side. In order to switch, the sixth original paper path a is passed and the seventh original paper path a is entered. When the sensor 16 detects the rear end of the original paper in the moving direction, the second switchback mechanism 10 is switched, and the original paper passes through the second original paper path a and enters the third original paper path a.
Similarly to the above, when the sensor 14 detects the trailing edge of the original paper in the moving direction, the first switchback mechanism 9 is switched. At the same time, the switching claw 13 is also switched to the fourth original paper path a side, and the original paper is conveyed in the order of the fourth and fifth original paper passes a and a, and is again placed on the original paper base glass 19. . At this time, the side of the manuscript paper opposite to the side that was copied first is facing down.

When the original paper is placed on the original paper table glass 19 again, the copying operation of the double-sided copying machine main body B starts, and the transfer paper is fed from the paper feeding cassette 25 by the paper feeding roller 26. The fed transfer paper passes through the first, second, and third transfer paper paths b, similarly to the transfer paper described above.
b, b, and is ejected onto the ejection tray 35 with the transferred side facing upward.

After double-sided exposure, the manuscript paper is placed on the manuscript paper table glass 19.
Although the paper is ejected from the top, the switching claw 13 is switched to the sixth document paper path a side in response to the double-sided exposure end signal.
For this purpose, the original paper passes through the sixth original paper path a and enters the seventh original paper path a. 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 the paper feed tray 1 is started. The original paper that has entered the seventh original paper path a is returned to the top of the paper feed tray 1 with the same side facing up as before being fed to the top of the paper feed tray 1 by paper discharge rollers 11 and 11a.

By repeating the above operations for the number of sheets of original paper set on the paper feed tray 1,
From the double-sided original paper, single-sided copy paper with the same page order as one set of original paper is placed on the paper discharge tray 35, and one cycle is completed.

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 sets of single-sided copy paper in the same page order as the original paper are placed on the output tray 35. Furthermore, the original sheets are placed on the paper feed tray 1 in the same page order as before copying.

As explained above, the sheet document conveying device according to the present invention has the advantage that the device is smaller and lighter, and furthermore, sheet documents can be guided to a predetermined position in the same front and back state as when stacked. There is.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the present invention, and FIG.
3 is a plan view showing details of the document separating section, FIG. 3 is a side view showing details of the document separating section, and FIG. 4 is a cross-sectional rear view side view showing the driving section. A... Circulating double-sided automatic document feeder, B... Double-sided copying machine main body, 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, 6b... Roller, 7... Conveyance belt drive roller, 7a... Conveyance belt driven Roller, 8... Conveyance belt, 9... First switchback mechanism, 10... Second switchback mechanism, 11, 11a... Paper discharge roller, 12, 1
3... Switching claw, 12a... Light source, 12b... Lens, 13... Switching claw, 13a... First mirror, 13
b...Second Mira, 13c...Third Mira, 13d...
...4th Mira, 14, 15, 16, 17, 18...
Sensor, 19... Original paper table glass, 20... Photosensitive drum, 21... Charger, 22... Developer, 2
3...Transfer charger, 24...Cleaner, 25...
...Paper feed cassette, 26...Paper feed roller, 27,2
7a...Register roller, 28...Transfer paper conveyance belt, 29, 29a...Fixing roller, 30...Transfer paper guide, 31, 31', 31'', 31...Transfer paper conveyance roller, 32...Intermediate tray , 33...
Paper refeed roller, 34, 34a... Paper discharge roller, 3
5... Paper output tray, 36... Sensor, 126...
...Partition plate, 127...Partition plate arm, 128...
Fulcrum, 129... Friction plate, 130... Shaft, 131
...Gear, 132...Gear, 132a...
Shaft, 133...Roller, 134, 135...Pin shaft, 136...Spring, 137...Outer circumference, 138...
...Axis, 139...Light sensor, 140...Sensor, 141...Motor, 142...Motor pulley, 143...Belt, 144...Belt, 14
5...Pulley, 146...Pulley, 147...
...Pulley, 148...Clutch, 149...Clutch, 150...Belt, 151...Belt,
152...pulley, a...first manuscript paper path,
a...Second manuscript paper pass, a...Third manuscript paper pass, a...Fourth manuscript paper pass, a...Fifth manuscript paper pass, a...Sixth manuscript paper pass, a...Seventh
Manuscript paper path, a... 8th manuscript paper path, b...
First transfer paper pass, b...Second transfer paper pass, b
...Third transfer paper pass, b...Fourth transfer paper pass,
b...Fifth transfer paper pass, b...Sixth transfer paper pass, b...Seventh transfer paper pass.

Claims (1)

[Scope of Claims] 1. A stacking means for stacking sheet originals, a separating feeding means for separating and feeding the sheet originals loaded on the stacking means one by one, and sheets fed by the separating feeding means. a first sheet path for switching the original document to a predetermined position from a first direction; a second sheet path for reversing the sheet document face-to-face and guiding it to the predetermined position from the first direction; a third sheet path for reversing the sheet original returned and discharged from the predetermined position, and guiding the original from the separation feeding side to the stacking means; the second sheet path and the third sheet path; A sheet document conveying device comprising: a sheet path switching means for switching the sheet path;