JPS6153291B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying machine that makes copies by transferring a developed image on a photoreceptor onto copy paper.

This type of copying machine has a main paper feeding device for feeding transfer paper into a paper feeding path and sending it to the copying process;
A paper ejecting device for ejecting already copied copies, and a paper feeding path in an inverted state for copying the copied copies on the back side of the ejecting device. A device including a sub-sheet feeding device for double-sided copying that is equipped with a sheet-feeding mechanism for feeding the sheet to the printer has already been proposed. In such a copying machine, in addition to making copies on both sides of a sheet of transfer paper, there is a demand for making multiple copies on the same side to make it easier to see various different data. Conventionally, in order to make multiple copies on the same side of transfer paper, a form is made in advance by printing or copying on the transfer paper, the form is fed into a normal paper cassette of a copying machine, and the image is superimposed on the paper. Forms must be created and synthesized, which is time-consuming and difficult to register.Furthermore, since forms must be created in advance, their storage and management is also time-consuming.

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to make multiple copies on the same side of transfer paper using a copying machine equipped with a sub-feeder for double-sided copying. Embodiments of the present invention will be described below with reference to the accompanying drawings.

The copying machine shown in the figure includes a transfer image forming device 1 that includes a photosensitive drum, a main paper feed device 2 that feeds stacked transfer sheets to the transfer image forming device, and a paper ejection tray that ejects the copied copies outside the machine. It is equipped with a paper ejecting device 3 for stacking sheets on top, and a sub-sheet feeding device 4 for double-sided copying.

The transfer image forming apparatus 1 includes a rotatable photosensitive drum 5, and a charging section 6, an exposing section 7, a developing section 8, a transferring section 9, and a cleaning section 10 are arranged along the outer periphery of the photosensitive drum 5. These are conventionally well known,
Therefore, I will not discuss it in detail here.

The main paper feeding device 2 includes a paper feeding table 11, transfer sheets 12 stacked thereon, a pick-up roller 13 for feeding out the uppermost transfer sheet, and a pair of separating rollers 14 and 15. The lower roller 15 of the separation roller pair rotates in the opposite direction to the feeding direction of the transfer paper, so that in the case of an accidental two-sheet feed, only the uppermost transfer paper is sent to the paper feed path 16; The second sheet of transfer paper will remain at the lower roller 15. The transfer paper fed through the paper feed path 16 has its lateral position corrected by the lateral position alignment roller 17 and reaches the transfer unit 9 via the registration roller 18 . The transfer image formed on the photoreceptor drum 5 is transferred to a transfer paper under the action of a transfer charger 19, and then the transfer paper is peeled off from the photoreceptor drum 5 by a peeling claw 20. The image carried on the transfer paper is then fixed by the fixing section 21, and the paper reaches the paper discharge device 3 and is stacked on the paper discharge table 22.

A first switching gate 23 is provided in the middle of the paper discharge path from the fixing unit 21 to the paper discharge device 3, and by switching this first switching gate, the transfer paper carrying the fixed image is transferred to the paper discharge tray 22 or The paper is sent to the sub-sheet feeding device 4. The sub paper feeder 4 passes through the first switching gate 23.
The transfer paper is then transferred to the intermediate tray 26 via the double-sided route 25 shown by a solid line for double-sided copying by the second switching gate 24, or to the multiple route 28 shown by broken lines passing through the forward conveyance path 27 for multiple copying.
Similarly, they reach the intermediate tray 26 and are stacked there. Therefore, the transfer sheets reaching the intermediate tray 26 via the double-sided route 25 are stacked here with the transferred image bearing surface facing up, and the transfer sheets passing through the multiplex route 28 are stacked here with the transferred image bearing surface facing down.
can be piled up. Guide plate 2 of forward rotation conveyance path 27
9 can be switched to the positions shown by the solid line and the broken line, and the transfer paper is introduced into the sorter via the feed belt 30 at the position shown by the broken line.

The intermediate tray 26 includes a paper feed tray 32 that is rotatable around a fulcrum 31, a paper stopper 33 that is movable depending on the paper size, and a paper feed tray lift lever 35 that is rotatably supported on the fulcrum 34. The paper feed tray lifting lever 35 supports the paper feed tray 32 at one end, and the other end under the action of the tension spring 37 supports the paper feed tray lowering cam 3.
It borders on 6. Reference numerals 38 and 39 are paper feed rollers and non-return rollers of the sub-sheet feeder 4, and 40 is a guide plate.

When making copies on both sides of transfer paper, transfer paper on which the transferred image of original A is formed on the upper surface is introduced and stacked on the paper feed tray 32 of the intermediate tray 26 via the duplex route 25. In response to the command, instead of feeding paper from the main paper feeder 2, the paper feed tray lowering cam 36 of the sub paper feeder 4 descends, and the paper feed tray lifting lever 35 moves clockwise under the action of the spring 37. The paper feed table 32 is rotated and lifted around the fulcrum 31, and the transfer paper on the paper feed table 32 comes into contact with the paper feed roller 38. Thus, due to the frictional action of the paper feed rollers 38, the uppermost transfer paper is sequentially fed through the guide plate 40 into the paper feed path 16 in a reversed state. In that case, the non-return roller 39 prevents the two-sheet feed. The back side of the thus-fed transfer paper, which does not carry a transfer image, is brought into contact with the photosensitive drum 5 on which the image of the B original is formed at this time, and a transfer image is formed on the same back side.

When combining copies of original A and original B on the same side of transfer paper, first a transfer image of original A is formed on the photosensitive drum 5, and this is transferred to the surface of the transfer paper fed from the main paper feeder 2. After transferring and fixing, the first and second switching gates 23 and 24 and the multiple route 28
are introduced into the intermediate tray 26 and stacked there. The original is replaced with the B original, and the paper feed tray lowering cam 36 is moved in accordance with the command as in the case of double-sided copying.
descends, lifts the paper feed tray 32, and sends out the normally rotating transfer paper to the paper feed path 16. Next, the transfer paper reaches the transfer section 9, but at this time, the surface that carries the copy of the A original comes into contact with the photosensitive drum 5 that forms the transferred image of the B original, and the image of the B original is superimposed on the image of the A original. created by Next, the transfer paper is transferred to the fixing section 2.
1, the paper is sent to the paper discharge table 22 according to the positions of the first and second switching gates 23, 24 and the guide plate 29, or to the sorter via the feed belt 30. In this way, this process is repeated until there is no more transfer paper in the intermediate tray 26, and the A original and B original
The required number of copies can be obtained by combining the images of the original.

As a sub-sheet feeding device, the second switching gate 24 and the transport path 27 for normal rotation are stopped, the first switching gate 23 immediately guides the transfer paper to the intermediate tray 26, and the normal rotation is used to perform multiple copies on the same side of the transfer paper. The paper feeding mechanism can be provided on the opposite side to the pair of paper feeding rollers 38 and 39. As a result, during double-sided copying, the transfer paper on the intermediate tray 26 is transferred to the reverse paper feeding mechanisms 38 and 3.
It is also possible to reach the paper feed path 16 in a reverse rotation state via 9 and 40, and to reach the paper feed path in a normal rotation state via a normal rotation paper feed mechanism when multiple copies are made on the same surface.

The developing section 8 can include a plurality of developing devices. The figure shows that two developing devices 8a and 8b are provided. By using toners of different colors in each developing device, it is possible, for example, to create an image of original A in black and an image of original B in blue or red. Thereby, copies with different colors on the front and back sides or copies with different colors for each image on the same side can be obtained. Furthermore, if each developing device 8a and 8b contains toner of a different color, for example, cyan and magenta, it is possible to obtain a so-called two-color copy of a multicolor original, and a rich variety of colors can be used for differential expression. Become.

As described above, in the present invention, the sub-sheet feeding device feeds the transfer paper in a reversed state and in a normal rotation state, and images of different originals can be formed on both sides of the transfer paper or on the same side as necessary. It is possible.

[Brief explanation of the drawing]

The figure is an explanatory diagram of a copying machine according to the present invention. 1... Transfer image forming device, 2... Main paper feeding device, 3
...Sheet discharge device, 4...Sub paper feed device, 8...Development section, 8a, 8b...Development device, 16...Paper feed path, 23...First switching gate, 24...Second switching gate , 26... Intermediate tray, 27... Forward rotation conveyance path, 32... Paper feed table, 38... Paper feed roller.

Claims (1)

[Scope of Claims] 1. A main paper feeding device 2 that feeds the transfer paper along the paper feed path 16 to the copying process 9, a paper discharge device 3 that discharges the copied transfer paper, and a transfer paper that has been copied on one side. A sub-sheet feeding device 4 equipped with a sheet feeding mechanism 38, 39 for storing paper and feeding it to the sheet feeding path for copying on the back side thereof, and sending the transfer paper to either a sheet discharging device or a sub-sheet feeding device. In a copying machine equipped with a first switching gate 23 for selective introduction, a second switching gate 24 is provided between the first switching gate and the sub-sheet feeding device, and this second switching gate At the first switching position, the transfer paper is guided to the sub-feeding device in an inverted state where copies are made on the back side, and at the second switching position, the transfer paper is guided to the sub-feeding device in a normal rotation state where multiple copies are made. A copying machine characterized by a guide to a device. 2. The copying machine according to claim 1, wherein the developing section is provided with a plurality of developing devices 8a and 8b each containing toner of a different color.