JPS61292165A - Copying device - Google Patents

Abstract

PURPOSE:To form a multiple picture image on one face of a sheet by providing on an image forming means a means for changing automatically a color of a developer, when bringing the sheet to refeed from a paper refeed means. CONSTITUTION:When the first switching guide plate 24 and the second switching guide plate 25 are in a full line position and a broken line position, respectively, for instance, a sheet which has completed copying on one face is inverted by an inversion guide part 21 and led out by an inversion main roller 19 and an after-inversion roller 20, and reaches a paper discharge tray 28. When the first switching guide plates 24, 25 are both in a full line position, the sheet which has been brought to an inversion action is fed out onto a carrying belt 29. When the third switching guide plate 32 is in a full line position, the sheet is fed into a collator, and when it is in a broken line position, the sheet which has completed copying on one face is contained in an intermediate tray 34 so that a picture image is turned upward, fed again to a feed paper path 5 by a pair of rollers 35, and subsequently, fed to an image forming process together with a replacement of an original, and copying is executed to the opposite face. In this way, a multicolor picture image can be formed easily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying apparatus capable of single-sided copying and double-sided copying.

PRIOR ART A copying apparatus of this type includes a paper feeding means for feeding stacked sheets one by one, an image forming means including the stages of forming, developing and transferring an electrostatic latent image, and an image formed by the image forming means. a fixing means for fixing the image on the sheet, a means for discharging the sheet to complete the copying, and a means for receiving the sheet to be passed through the fixing means and feeding the sheet again to the image forming means for double-sided copying or multiple copying of one side. Those with paper refeeding means,
Already proposed.

1-09 - An object of the present invention is to form multiple images of different colors during multiple copying of one side in the above-mentioned copying apparatus.

-Configuration.

According to the present invention, the above object is to provide a switching means for selectively guiding a sheet to either a sheet discharging means or a sheet refeeding means. This is achieved by providing the imaging means with means for automatically changing the color.

The present invention will be described in detail below with reference to the accompanying drawings.

In Figure 1, the paper feed section 1 that feeds sheets one by one is 3
There are three paper feed trays 2, 3, and 4, each of which is adapted to stack and store sheets of different sizes. In addition, each paper carrier has pick-up rollers 2a and 3a for feeding out the uppermost sheet.

4a and divided roller pairs 2b, 3b, and 4b, respectively. The lower roller of the pair of separation rollers rotates slowly in the opposite direction to the sheet feeding direction, thereby preventing double-sheet feeding caused by an inadvertent feeding row. The sheets from each paper feed table then reach the paper feed path 5, pass through a pair of feed rollers 6, 7, and 8 disposed on a saw, and reach a buffer part 9, where the lateral position is corrected by a diagonal roller 10. The registration roller pair 11 is reached. Next, the sheet is sent to a transfer section equipped with a transfer device 13 in synchronization with the powder image formed on the photoreceptor drum 12, and the powder image on the photoreceptor drum 12-1- is transferred to this sheet, and then Under the cooperation of the separation belt 14, the sheet is separated from the photoreceptor drum and reaches a pair of fixing rollers 15.

The image-fixed sheet carried by the fixing roller pair 15 is
The sheet then passes through a transfer roller pair 16 and reaches a reversing roller row attached to a sheet reversing device 17. In particular, as shown in detail in FIG. 2, the reversing roller array includes a pre-reversing roller 18, a main reversing roller 19 in contact with the pre-reversing roller 18, and a post-reversing roller 20 in contact with the main reversing roller. Further, the reversing device 17 includes a reversing guide section 21, and guide plates 22 and 23 are arranged at a sheet introduction position into the reversing device 17 and a sheet leading-out position from this, respectively.

Reference numeral 24 denotes a first switching guide plate, which has a solid line position for guiding the sheet entering the reversing roller row to the reversing guide section 21 and reversing the sheet, and a position indicated by the solid line for preventing the sheet from entering the reversing guide section 21. Two positions can be taken, including the position shown by the broken line for allowing the unreversed brush to run out of the reversing roller row.

A second switching guide plate 25 is arranged on the sheet lead-out path from the reversing device 17. This second switching guide plate 25
When the sheet is in the position shown by the solid line in the figure, the sheet is guided to the conveyor belt device 29 shown in FIG. 27 and is discharged onto a paper discharge tray 28.

The conveyor belt device 29 includes a belt 30 and a roller 31 that cooperates with the belt 30, and a third switching guide plate 32 is provided at the end of the conveyance. When the third switching guide plate is at the position shown by the solid line, the sheet is sent from the conveyor belt system [29] to the collator via the pair of feed rollers 33, and when the third switching guide plate 32 is at the position shown by the broken line, the sheet is sent to the collator. It is guided and stored on the intermediate tray 34. This intermediate tray 34
A pair of rollers 35 for refeeding paper are provided oppositely.

36 is a presser for the sheets stacked on the intermediate tray 34, and 37 is a pair of delivery rollers for the sheets sent out by the pair of rollers 35.

The operation mode of the sheet path switching of the copying apparatus according to the present invention described above is as follows.

(1) First switching guide plate 24 and second switching guide plate 2
5 are both at the dashed line position in FIG. 2, the fixing roller pair 1
The sheets that have passed through 5 are ejected to a paper ejection tray 28 without reaching the reversing guide section 21, and are stacked on this N. This is the same as in conventional general copying apparatuses, and since the image on the sheet on the paper ejection tray faces upward, the order of the pages is reversed when copying from the first page of the original.

(2) When the first switching guide plate 24 is in the solid line position and the second switching guide plate 25 is in the broken line position, for example, a sheet to be copied on one side reaches the reversing guide part 21 and the second switching guide plate 25 is in the broken line position.
The sheet is reversed by the main reversing roller 19 and the reversed roller 20, and then reaches the paper discharge tray 28. At this time, the images of the sheets on the paper discharge tray are facing downward, and therefore they are arranged in page order.

(3) First switching guide plate 24 and second switching guide plate 2
5 are both in the solid line position in FIG.

When the third switching guide plate 32 is at the solid line position.

The sheet is sent to the collator.

When the third switching guide plate 32 is in the broken line position, the sheet to be copied on one side is stored in the intermediate 1-lay 34 with the image facing upward, and then transferred to the paper feed path 5 again by the roller pair 35, and then transferred to the original sheet. When it is replaced, it is sent to the image forming process and copied on the opposite side. The sheets that can be copied on both sides can then be stored in the paper discharge tray 28 in a desired orientation by operating the first switching guide plate 24 and the second switching guide plate 25, or sent to the collator via the conveyor belt device 29. I can do it.

(4) When the first switching guide plate 24 is in the broken line position and the second switching guide plate 25 is in the solid line position, the sheet is sent onto the conveyor belt device 29 without being subjected to a reversing action.

When the third switching guide plate 32 is in the solid line position, the sheet can be fed into the collator.

When the third switching guide plate 32 is at the dashed line position, a sheet on which copying has been completed on one side is stored on the intermediate tray 34 with the image facing downward. Therefore, when replacing the original and refeeding this sheet to the image forming process, multiple images can be formed on the same surface, and in that case, the color of the developer can be automatically changed to form a multicolor image. is also possible. As described above, the sheets on which multiple images (including multicolor images) are to be formed are stored on the paper output tray in a desired orientation by operating the first switching guide plate and the second switching guide plate. , or can be sent to a collator.

In the case of double-sided copying, if the roller pair 35 for feeding the sheet from the intermediate tray 34 is started using a signal from the document feeder or a switch linked to the pressure plate, double-sided copying operation can be reliably expected. .

Furthermore, during a series of double-sided copying operations, if there is no image on the back side, after the image is created on the first side, the sheet is passed through the sheet reversing device, passed through the second switching guide plate 25, and then transferred to the paper output tray 2.
Paper can be ejected to 8.

In FIG. 3, the first switching guide plate 38 is connected to the transfer roller pair 1.
6 and the sheet reversing device 17, and a second switching guide plate 39 is arranged in the sheet lead-out path from the sheet reversing device 17. 40, 41, and 42 are fixing guide plates. When the first switching guide plate 38 is at the solid line position, the sheet that has passed through the fixing device is transferred to the sheet reversing device I7.
The sheet is then reversed and guided out by the reversing main roller 19 and the post-reversing roller 20, and then, when the second switching guide plate 39 is in the solid line position, the sheet is sent to the conveyor belt device, and the sheet is transferred to the second switching guide. When the plate 39 is at the broken line position, the paper passes through the pair of feed rollers 26 and reaches the paper discharge tray.

When the first switching guide plate 38 is at the broken line position, the sheet does not pass through the sheet reversing device 17 and the second switching guide plate 38
According to the position of 9, the paper is sent to the paper discharge tray or to the conveyor belt device.

As described above, the copying apparatus according to the present invention can form a multicolor image on one side of a sheet very easily, and has a great practical advantage.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a copying apparatus to which the present invention is applied, FIG. 2 is an enlarged view of essential parts of a reversing device, and FIG. 3 is an explanatory diagram showing another example of the reversing device. 1...Paper feeding section 13...Transfer section 15
...Fixing roller pair 17...Sheet reversing device 24.38...First switching guide plate 25.39...Second switching guide plate 27...Paper output roller pair 28...Paper output tray 32...Third switching guide plate 34...Intermediate tray

Claims (2)

[Claims] (1) A paper feeding means that feeds the stacked sheets one by one;
An image forming means including the stages of forming, developing and transferring an electrostatic latent image; a fixing means for the image formed on the sheet by the image forming means; a sheet discharging means for completing copying; and a fixing means. In a copying apparatus having a sheet refeeding means that receives a sheet that passes through the image forming means and sends the sheet to the image forming means again, the sheet is ejected and refeeded after the fixing means in the sheet traveling direction. The image forming means is provided with a switching means for selectively guiding the developer to one of the paper means, and a means for automatically changing the color of the developer when refeeding the sheet from the refeeding means. Characteristic copying device. (2) A sheet reversing device is disposed in the sheet path between the fixing means and the paper refeeding means, and the sheet reversing device is provided with means for selectively reversing the sheet and passing the sheet in an uninverted state. 2. A copying apparatus according to claim 1, characterized in that: