GB1598604A - Photocopying machine - Google Patents

Description

(54) PHOTOCOPYING MACHINE (71) We, XEROX CORPORATION, of Xerox Square, Rochester, New York, United States of America, a corporation organised under the laws of the State of New York, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to photocopying machines arranged to copy onto both sides of copy material.

In forming images on both sides of a copy sheet in a photocopying machine, it is usual to pass the sheet through the machine to obtain an image on one side and then store the sheet. The stored sheet is later recycled through the photocopying machine to receive an image on its other side. In its simplest form in stlch a photocopying process the sheet is returned straight away, as soon as the next image is ready, to receive its second image on its other side.

According to the present invention there is provided a photocopying machine for making duplex copies, having a transfer station where images are transferred to copy sheets and a copy sheet feeding system, said sheet feeding system comprising an open, operator accessible, buffer storage tray, sheet feeding means for feeding sheets from a sheet supply tray to the transfer station to receive an image on one side thereof, sheet feeding means for feeding the sheets with an image on one side thereof from the transfer station to the buffer storage tray, and sheet feeding means for feeding sheets from said buffer storage tray to said transfer station to receive an image on the other side thereof forming duplex copies.

A photocopying machine having a sheet feeding system according to the invention will now be described by way of example with the reference to the accompanying drawing which shows the machine schematically.

The sheet feeding system includes a supply tray 10 which has a bottom feeder 11 for drawing copy sheets out of the tray 10 and feeding the sheets along an arcuate guide and into contact with a belt feeder 13. The feeder 13 feeds sheets through an image transfer station 14 where an image is transferred from a photoreceptor 15 onto the copy sheet. After the transfer station 14 the sheet is driven around a 180 arcuate guide 16 and then fed by belt feeders 17 and 18 into an open buffer storage tray 19. The tray 19 is provided with a bottom feeder 20 for feeding sheets from the tray 19 into contact with the belt feeder 13.

The photocopying machine includes a platen 21 on which originals are placed for copying. An optional scanning system is provided for projecting an image of an original onto the photoreceptor 15. Developer station 22 and cleaning station 23 are provided on either side of the transfer station 14. The optical system and the developer transfer and cleaning stations can be any conventional type, all of which are wellknown in the art of photocopying machines.

The photocopying machine can be used for simplex copying in conventional manner in which case the copy sheets are either fed out of the machine by extra means not shown or collected in the tray 19 after passing once through the transfer station 14. In duplex mode, the operation of the machine is as follows: Original documents are arranged in ascending (or decending) page order of odd numbers, for example 1,3,5, etc. and placed on the platen in that order. In the machine described, this is carried out manually by an operator. However, if there is an automatic document handler provided, the pages are arranged to be fed, in the order mentioned above, by the document handler. Copy sheets are fed from the supply 11 in sequence and receives respective images of the odd numbered sheets at the transfer station 14.

The sheets are then each fed into the buffer tray 19.

Original documents arranged in ascending (or descending respectively) page order if even numbers 2,4,6, etc. are then placed on, or supplied to, the the platen 21. Copying then takes place feeding sheets from the buffer tray 19 past the transfer station 14 and back into the tray 19. At the end of that sequence the tray 19 has a complete and ordered duplex copy set of the original documents.

It will be noted if there is a total of originals which is an odd number, the finished set in the tray 19 will be in order except for the last page which will be at the bottom of tray 19. It is possible, if desired, to arrange for this last sheet to pass around the sheet feeding system without receiving an image so as to be in its correct position in the finished set in the tray 19.

The arrangement of the tray 19 as an open tray which is readily accessible to the operator makes it a simple matter to cope with any malfunction during the duplex copying of a set. For this reason, the tray is preferably positioned as shown next to or near the platen 21 where the operator can observe and supervise the machine if necessary. It will also be noted that the open access of the tray 19 means, as described, that the tray 19 can act as an output tray for simplex or duplex copying as well as a buffer tray.

WHAT WE CLAIM IS: 1. A photocopying machine for making duplex copies, having a transfer station where images are transferred to copy sheets and a copy sheet feeding system, said sheet feeding system comprising an open, operator-accessible, buffer storage tray, sheet feeding means for feeding sheets from a sheet supply tray to the transfer station to receive an image on one side thereof, sheet feeding means for feeding the sheets with an image on one side from the transfer station to the buffer storage tray, and sheet feeding means for feeding sheets from said buffer tray to said transfer station to receive an image on the other side thereof forming duplex copies.

2. A photocopying machine according to claim 1, in which the buffer storage tray is adjacent a platen for supporting original documents to be copied.

3. A photocopying machine according to claim I or 2, in which there is provided for the buffer storage tray a bottom feeder.

4. A photocopying machine according to claim 1, 2 or 3, in which the buffer tray also acts as an output tray for the duplex copies.

5. A photocopying machine having a sheet feeding system substantially as herein described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. buffer tray 19 past the transfer station 14 and back into the tray 19. At the end of that sequence the tray 19 has a complete and ordered duplex copy set of the original documents. It will be noted if there is a total of originals which is an odd number, the finished set in the tray 19 will be in order except for the last page which will be at the bottom of tray 19. It is possible, if desired, to arrange for this last sheet to pass around the sheet feeding system without receiving an image so as to be in its correct position in the finished set in the tray 19. The arrangement of the tray 19 as an open tray which is readily accessible to the operator makes it a simple matter to cope with any malfunction during the duplex copying of a set. For this reason, the tray is preferably positioned as shown next to or near the platen 21 where the operator can observe and supervise the machine if necessary. It will also be noted that the open access of the tray 19 means, as described, that the tray 19 can act as an output tray for simplex or duplex copying as well as a buffer tray. WHAT WE CLAIM IS:

1. A photocopying machine for making duplex copies, having a transfer station where images are transferred to copy sheets and a copy sheet feeding system, said sheet feeding system comprising an open, operator-accessible, buffer storage tray, sheet feeding means for feeding sheets from a sheet supply tray to the transfer station to receive an image on one side thereof, sheet feeding means for feeding the sheets with an image on one side from the transfer station to the buffer storage tray, and sheet feeding means for feeding sheets from said buffer tray to said transfer station to receive an image on the other side thereof forming duplex copies.

2. A photocopying machine according to claim 1, in which the buffer storage tray is adjacent a platen for supporting original documents to be copied.

3. A photocopying machine according to claim I or 2, in which there is provided for the buffer storage tray a bottom feeder.

4. A photocopying machine according to claim 1, 2 or 3, in which the buffer tray also acts as an output tray for the duplex copies.

5. A photocopying machine having a sheet feeding system substantially as herein described with reference to the accompanying drawing.