JPS61145568A - Both-surface recording device - Google Patents

Abstract

PURPOSE:To reduce the size of a device and to perform both-surface recording speedily by providing a inverting and conveying device which receives copying paper to which a toner image is transferred by a transfer part from an image carrier and inverts and sends out it to another transfer device. CONSTITUTION:The toner image on the image carrier 1 is transferred to the copying paper P by a transfer device 10 and the copying paper P is separated from the surface 1 of the carrier by the inverting and conveying device 11 and rotated as shown by an arrow (a). When the toner-image transfer surface of the copying paper P conveyed by the device 11 finishes moving beyond the irradiation position of a flash exposure lamp 18, the device 11 is switched immediately to arrow-(b) rotation and the copying paper P is sent out to a pressure transfer roller 14. Consequently, the gap between a toner image transferred to the reverse surface of the copying paper P by the transfer device 10 and the toner image transferred to the reverse surface of the copying paper P by the roller 14 is shortened on the surface of the carrier 1, thereby shortening a both-surface copying operation time.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a double-sided recording device, and more specifically, toner images are formed one after another on the surface of a rotating image carrier, and the toner images are sequentially transferred to a recording material. The present invention relates to a double-sided recording device that transfers and fixes images onto the front and back sides of a computer.

[Prior art]

In a typical conventional double-sided recording device, the recording material with the toner image transferred and fixed on the surface is reversed and fed into the first recording material feed tray or a relay tray installed at a similar location. From there, it is sent out again to the same transfer and fixing path. In such a double-sided recording apparatus, the transfer and fixing means are used for recording on both the front and back sides, so the structure of the recording apparatus is simplified in this respect.

Although it has the advantage of reducing the size and cost of the device, the conveyance path of the recording material for recording on the back side is not flammable, and especially when double-sided recording is performed for one copy, the image carrier surface There is a problem in that the play surface becomes larger and recording takes more time.

Also, as seen in Japanese Patent Application Laid-Open No. 54-121132,
Toner images for the front and back sides are formed on two image carriers, respectively, and the toner images are used for the front side of a sheet of copy paper.

A double-sided recording device is also known in which images are simultaneously transferred to the back side and fixed by a fixing device from the front and back sides. Although this double-sided recording device has the advantage of being able to perform double-sided recording in a short time, it requires two sets each of image carriers, high exposure means, transfer means, fixing means, etc., making the recording device large and costly. The problem is that it gets expensive.

[Purpose of the invention]

The present invention was made in order to solve the above-mentioned problems with conventional double-sided recording devices, and the present invention has a number of advantages.The conveyance path for the recording material for recording on the back side is short, and double-sided recording can be performed quickly. The present invention provides a double-sided recording device in which an image carrier and an image forming means are worn for recording on both sides.

[Structure of the invention]

The present invention provides a first transfer section and a second transfer section along the surface movement path of a rotating image carrier, and the first transfer section carries an image between the first transfer section and the second transfer section. The above object is achieved by a double-sided recording device characterized in that it is provided with a reversing conveyance means for receiving a recording material onto which a toner image has been transferred from a recording medium, reversing it, and sending it to a second transfer section.

〔Example〕

The present invention will be explained below using illustrated examples.

The figure shows an outline of a double-sided copying apparatus showing an embodiment of the present invention.

The main configuration diagram is a drum-shaped image carrier having a photoreceptor layer on its surface and rotating in the direction of the arrow, 2 a static elimination lamp that removes the charge on the image carrier 1, and 3 a static-eliminated image carrier. body 1
4 is an image exposure device that exposes the image of the document O on the platen to the charging surface of the image carrier 1 to form an electrostatic image; 5 is a device that develops the electrostatic image into a toner image; Developing device, 6
1 is a pre-transfer static elimination lamp for erasing the charge on the surface of the image carrier 1 on which a toner image is formed to increase the transfer efficiency of the toner image; 7 is a paper feed cassette; 8 is a paper feed cassette 7
9 is a registration roller that feeds the copy paper P to the transfer position in synchronization with the toner image on the image carrier 1, and 10 is a registration roller that feeds the copy paper P one by one from the toner image carrier 1 by corona discharge. A transfer device for transferring an image onto copy paper P, 1
Reference numeral 1 denotes a reversing conveyor means 14 that rotates in the directions of arrows a and b, such as an endless belt stretched between drive rollers 12 and 13;
15 is a pressure transfer roller that presses the copy paper P against the surface of the image carrier 10 and transfers the toner image onto the copy paper P; 15 is a transparent endless belt or hollow endless belt stretched between the pressure transfer roller 14 and the drive roller 16; A feeding conveying means 17 rotates in the direction of arrow C to feed out the copy paper P, and 17 separates the copy paper P on which the toner image has been transferred by the transfer device 10 from the surface of the image carrier 1 and moves it in the direction of arrow a. When the reversing conveying means 11 rotates in the direction indicated by the arrow C, the copy paper P is separated from the reversing conveying means 11 and the sending conveying means rotates in the direction indicated by the arrow C. a movable separating member, 18, leading along pressure transfer roller 14 along 15;
irradiates the toner image transfer surface of the copy paper P conveyed in the direction of arrow a by the reversing conveyance means 11 through the sending-out conveying means 15, and the toner of the copy paper P sent out in the direction of arrow C by the sending-out conveying means 15. A flash exposure lamp 19 irradiates heat rays directly onto the image transfer surface to fix the toner image on the copy paper PGC, and 19 removes static electricity from the surface of the image carrier after the toner image is transferred, and the remaining toner is removed by the next cleaning device 20. This is a static eliminator to make it easier.

In such a copying apparatus of the present invention, copy paper P is conveyed by reversing conveyance means 11 rotating in the direction of arrow a.
Immediately after the toner image transfer surface of P has passed the irradiation position of the flash exposure lamp 18, the reversing conveyance means 11 is switched to rotate in the direction of the arrow, and the copy paper P is transferred to the pressure transfer roller 14.
By sending the toner image to the surface of the copy paper P by the transfer device 10 and the toner image transferred to the back surface of the copy paper P by the pressure transfer roller 14, the toner image is transferred to the surface of the image carrier 1 by the pressure transfer roller 14. The gap between the two sides can be shortened, and the double-sided copying time can be shortened.

It goes without saying that the toner image transferred by the transfer device 1O and the toner image transferred by the pressure transfer roller 14 are formed by exchanging the original 0. Such exchange of document 0 can be done manually or automatically by known means.

The present invention is not limited to the illustrated example; the latent image may be formed on the image carrier by an electrostatic recording method or a magnetic recording method.
2 may be a pressure transfer roller. Alternatively, a corona discharge transfer device may be used in place of the pressure transfer device 214, and instead of a dual-purpose flash exposure device, the heat source # In that case, the reversing conveyance means 1 may be fixed on the feed-out conveyance means 15.
Needless to say, an endless belt similar to No. 1 will be used. However, the illustrated embodiment is preferable because the recording apparatus can be made compact and the fixing means can also be used. In order to improve the transfer efficiency of the toner image, it is preferable to apply a DC bias voltage between the pressure transfer roller 14 and the base of the image carrier 1, and also to apply a DC bias voltage to the drive roller 12 of the reversing conveyance means 11. A direct current bias voltage may be applied so that the separation and reception can be easily performed. The movable separation member 17 may be omitted by using such means, or the separation member may be provided on the static eliminator 19 side of the pressure transfer cooler 14.

〔Effect of the invention〕

As described above, the double-sided recording device of the present invention has a very short transportation path for the recording material for recording on the back side, can quickly perform double-sided recording, and has an image carrier and an image forming means. It is also used for recording on both sides, and has the excellent effect of making the recording device small and inexpensive. It goes without saying that the double-sided recording apparatus of the present invention can perform not only double-sided recording but also single-sided recording. That is, in the illustrated double-sided copying apparatus, the copy paper P may be ejected as is without reversing the reversing conveyance means 11, or the position of the reversing conveyance means 11 may be changed to allow the sheet to be fed out and conveyed. The copy paper P may be ejected by the means 15, or in that case, the transfer device 10 is not operated and the transfer is performed by the conveying means 15 or the pressure transfer roller 14 to which a DC bias is applied. It's okay.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is a schematic configuration diagram of a double-sided copying apparatus showing an embodiment of the present invention. 1... Image carrier, 2... Static elimination lamp, 3
... Charger, 4... Image exposure device, 5.
...Developing device, 6...Pre-transfer static elimination lamp, 7
...Paper feed cassette, 8...Paper feed roller, 9.
...Registration roller, 10...Transfer device, 11...
・Reversing conveyance means, 12.13... Drive roller, 1
4... Pressure transfer roller, 15... Delivery conveyance means, 16... Drive roller, 17... Movable separation member, 18... Flash exposure lamp, 19... Static eliminator, 2o... cleaning equipment.

Claims (5)

[Claims] (1) A first transfer section and a second transfer section are provided along the surface movement path of the rotating image carrier, and the image carrier is mounted at the first transfer section between the first transfer section and the second transfer section. 1. A double-sided recording apparatus comprising a reversing conveyance means for receiving a recording material having a toner image transferred thereto, reversing it, and sending it to a second transfer section. (2) The double-sided recording apparatus according to claim 1, wherein a corona discharge transfer device is used in the first transfer section. (3) The screen recording device according to claim 1 or 2, wherein a pressure transfer roller is used in the second transfer section. (4) The double-sided recording device according to claim 3, wherein the pressure transfer roller of the second transfer section constitutes a part of a conveying means for sending out the recording material to which the toner image has been transferred at the second transfer section. . (5) The toner image transferred at the first transfer section is recorded on the reversing conveyance means, and the toner image transferred at the second transfer section is recorded on the sending-out conveyance means by a flash exposure means that also serves as a recording device. A double-sided recording device according to claim 4, which is fixed on a material.