JPH02264973A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent deviation of a transferring paper and to guide a transferring paper to a fixing part safely and surely by providing a function means provided movable, a guiding means which conducts a recording paper, and a separating means which separates the function means from a conducting path. CONSTITUTION:A color copying device 1 is constituted of a color image reading device 5 and a color recording device 3, a destaticizing / electrifying device 33 which is the function means and a path switching member 35 are provided in the device 3. The guiding means and the separating means are constituted of the member 35 and the destaticizing / electrifying device 33 with controlling means of each. In the transferring process of the device 3, corona charging of a specified polarity is carried out by the electrifying device 33, with the control of the controlling means, and an electro conductive body belt 17 and all the surface of the transferring paper P are adhered together to prevent deviation of paper position during the carrying. When the process is completed and is progressing to the fixing process, by carrying out the destaticizing of the transferring paper P by the destaticizing device 33, the paper is separated from the belt 17, and is traveled to a specified position outside the carrying path. At this time, the transferring paper P is guided safely and surely to the fixing means 37 without coming into contact with the destaticizing / electrifying device 33 by the member 35. Thus generation of paper jamming, etc., is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an image forming apparatus that transfers an image to the transfer material multiple times by reciprocating the transfer material.

(Conventional Technique 1) Conventionally, there is a technique related to an image forming apparatus for transferring an image multiple times to two sheets of transfer paper as a transfer material, such as color electrostatic photography or overlapping copying.

In color electrophotography, etc., it is important to accurately superimpose images during transfer, and there are generally two types of transfer means for performing this transfer, for example, one using a transfer drum and one using a dielectric belt. known as.

For those that use a transfer drum, the image is transferred multiple times with the transfer paper wrapped around the transfer drum, so images can be overlaid accurately and there will be no color misalignment. Since it is necessary to wrap the transfer paper over the entire surface of the transfer paper, problems arise such as the need to increase the size of the transfer drum to match the size of the usable transfer paper.

On the other hand, when using a dielectric belt, the size of the transfer paper used is not limited by the circumference of the endless wide belt, but on the other hand, the transfer paper is ejected out of the stomach after every - transfer. However, since the paper is configured to be re-fed, accurate overlapping is difficult. To solve this problem, there is a copying apparatus described in Japanese Unexamined Patent Publication No. 118366/1983. In other words, this device reciprocates the transfer paper sent in to transfer the visible image around the transfer section according to the number of overlapping operations without ejecting it from the machine. According to this copying apparatus, the transfer paper, a part of which is attracted to the dielectric belt, is reciprocated with the transfer section as a boundary to perform overlapping copying, so that the leading edge and the registration on both sides of the images that are aligned by refeeding the paper are removed. It is characterized by the fact that no misalignment occurs, and because it eliminates the need for a transfer drum around which transfer paper is wound, it contributes to the miniaturization of color copying apparatuses.

However, the copying apparatus described in JP-A-82-118366 does not have a charger for re-adsorbing the transfer paper to the dielectric belt during multiple transfer steps, and in some cases, the image There is a risk that misalignment or jamming may occur in overlapping.

To explain this specifically, when the transfer paper is at the post-transfer stop position, about two-thirds of the leading edge of the transfer paper is separated from the dielectric belt and is on the paper switching member and the paper leading edge guide plate. The transfer paper of the paper switching member and the paper leading edge guide Saka-E is equipped with a static eliminator to prevent image disturbance due to peeling discharge and sticking of the transfer paper to the paper leading edge guide plate when it is separated from the dielectric belt. Since the static electricity is removed, the static electricity that had been charged is discharged, and when the transfer paper is returned, the re-adsorption force to the dielectric belt becomes extremely weak. Especially return complete Tll3
In the ``L position, only the portion of the transfer paper on the leading edge side 273 from which electricity has been removed is always placed on the dielectric belt, so the force of the dielectric belt to hold the transfer paper is weak. This causes the transfer paper to easily shift due to the sticking of the trailing edge of the transfer paper to the paper trailing edge guide when transporting the transfer paper, and the impact when restarting for the next transfer, making it difficult to superimpose images. This causes misalignment.

On the other hand, when installing a charger to re-adsorb the reciprocating transfer paper to the dielectric during multiple transfer processes, the charger is placed close to the transfer paper in order to efficiently apply static electricity to the transfer paper. It is provided on the downstream side of the transfer means. Therefore, if the transfer paper is thin and has low paper stiffness, the transfer paper will be guided along the paper switching member etc., but if the paper is thick and has strong paper stiffness, then the transfer paper will be guided along the paper switching member etc.

The transfer paper does not fully follow the paper switching member, etc., and lifts up in the middle (for example, as shown by the two-dot chain line in FIG. 3), and is stained by contact with the charger, and furthermore, the charge The transfer paper got caught in the container, causing a paper jam.

(Object of the Invention) The present invention has been developed in view of the above circumstances, and is intended to prevent the transfer paper from shifting when transferring an image to the transfer paper multiple times by moving the transfer paper back and forth, and to prevent the transfer paper from shifting. It is an object of the present invention to provide an image forming apparatus that safely and reliably guides images to a fixing section.

(Structure of the Invention) In order to achieve the above object, the image forming apparatus of the present invention transfers an image by reciprocating a transfer material with respect to an e-copying device, and then conveys the transfer material to a fixing device to form an image. In an image forming apparatus that performs fixing, a functional means that functions on the reciprocating transfer material and is configured to be movable;
During the reciprocating movement of the transfer material, a guide means guides the transfer material to a predetermined path during the transfer process and guides it to a fixing means when the transfer process is completed; The present invention is characterized in that it includes a separating means for moving the functional means and separating it from the guiding path when the functional means is guided to the fixing means.

Hereinafter, one embodiment of the present invention will be described in detail using the accompanying drawings.

First, the configuration of a color copying apparatus according to the present invention will be explained with reference to FIG.

The color copying bag [1 of this embodiment] is composed of a color recording bag 0!3 and a color image reading device 5 installed above the color recording device i3.

The color image reading device t5 has a well-known configuration, and reads, for example, three color separated lights of Blue, Green, and Red, and performs five image arithmetic processing based on the intensity level of each color light. , C, and Bk (black), and sends the image data to the color recording device r113. At this time, the image data manually input to the color recording device 3 may be processed by other color image processing systems (for example, a color facsimile, a word processor,
The image data may be output from a personal computer, etc.), and the connection interface for this may be individually supported.

Next, the configuration of the color recording device 3 will be explained. The photoreceptor belt 7 has a photoreceptor layer coated on the outer peripheral surface of an endless wide belt, on which an electrostatic latent image is formed by irradiation with light, and a photoreceptor belt drive roller 7a and a photoreceptor belt driven roller 7b. etc., in an oval shape.

Further, around the photoreceptor belt 7, a charging means 9 for charging the photosensitive layer to a predetermined polarity, and an optical system 11 for scanning and exposing an optical image to the photosensitive layer to form an electrostatic latent image. A developing means 13 that develops the electrostatic latent image formed by the exposure, a transfer means f5 that transfers the image developed by the developing means 13, that is, a toner image, onto the transfer paper P, and a dielectric belt 17.
．． A photoreceptor belt cleaner 19 and a static eliminator 21 are arranged to respectively remove toner and charges remaining on the photoreceptor belt 7 without being transferred to the transfer paper P during the transfer means 5.

The 1TiI developing means 13 includes a Y image developing means +3 (Y) for developing image data of Y color, an M image developing means 13 (M) corresponding to image data of the same color, and an image of the same C color. C image developing means 13 (C), Bk corresponding to the data
Bk image developing means 13 (Bk
).

Further, in FIG. 1, the dielectric belt 17, which is disposed so as to be able to come into contact with and separate from the lower end portion of the photoreceptor belt 7 that rotates clockwise, is an endless wide belt having approximately the same width as the photoreceptor belt 7. A paper feed tray 23 that accommodates transfer papers P stacked from the transport direction and the flow side, and a paper feed roller 25 that takes out and feeds the transfer papers P stacked on the paper feed tray 2a one by one from the upper side. A pair of registration rollers 27 are arranged to feed the transfer paper P fed by the paper feed rollers 25 toward the dielectric belt 17 in synchronization with the image (toner image) on the photoreceptor belt 7.

Further, a dielectric belt 17 is sandwiched between the registration roller pair 27 and the transfer means 15, and the dielectric belt I7 and iq
The contact/separation switching roller 29 with the photoreceptor belt 7 and the transfer paper P
A paper adsorption charger 31 that applies an electric charge to the transfer paper P and causes the transfer paper P to be attracted to the dielectric belt I7 is disposed opposite to the paper adsorption charger 31.

Further, at the upper part of the other end of the dielectric belt 17, a charger 33, which will be described later as a functional means, is disposed so as to be movable in the direction away from the conveyance path. A path switching member 35 that changes the conveyance path of the transfer paper P is configured to be swingable. The path switching member 35 guides the transfer paper P to the paper leading edge guide plate G2 when transferring images multiple times under the control of a control means (not shown), and guides the transfer paper P to the paper leading edge guide plate G2 when the transfer process is completed. It is guided to the fixing means 37 arranged above the guide G2.

The fixing means 37 fixes the toner image transferred to the transfer paper P with a roller.

The path switching member 35 and the control means constitute a guide means, and the charge remover/charger 33 and the control means constitute a separating means.

Further, a paper trailing edge guide G1 is arranged at a position opposite to the paper leading edge guide G2 across the dielectric belt 17, and a paper trailing edge guide G1 is arranged on the F side of the dielectric belt 17 mentioned in 11i to remove toner attached to the dielectric belt 17. The configuration of the zero-order static eliminator/charger 33 in which the dielectric belt cleaner 39 and the static eliminator 41 for removing accumulated charges are disposed will be described with reference to the block diagram of FIG. 2.

The charge remover/charger 33 has two circuits: a high voltage circuit 33a for paper static elimination and a high voltage circuit 33b for paper adsorption.

The paper static elimination high voltage circuit 33a includes a paper static elimination output trigger input terminal 3'+ (hereinafter simply referred to as yl terminal).

The paper suction high voltage circuit 33b is provided with input terminals ya (hereinafter simply referred to as y2 terminals) for paper suction output. When a trigger signal is input to the ++yl terminal, a high voltage output 1 for paper static elimination, for example, an AC output is provided. The charge is applied to the charge remover/charger 33 so that the transfer paper P can be easily separated from the dielectric belt 17. Furthermore, when a signal is input to the terminal y, a high voltage output for paper adsorption, for example a DC output of a predetermined polarity, is applied to the charge remover/charger 3:3.

Next, with reference to FIGS. 3 and 4, the application timing of the charge remover/charger 33 and the path switching member 35 will be described.
The operation will be explained.

First, at times t and I, the transfer drive motor 0N10FF signal (
When the C signal (hereinafter referred to as C signal) becomes ON state (H level), a transfer drive motor forward rotation start signal (hereinafter referred to as F, b signal) is output, and the transfer drive motor starts forward rotation.
At time t3, when a 5, for example, Y image is transferred to the transfer paper P, a reverse start signal (hereinafter referred to as the C signal) for the transfer drive motor is output and the forward rotation starts. The transfer drive motor that was previously running starts rotating in reverse. At this time, the rotation speed of the transfer drive motor performs high-speed reverse rotation, as is clear from the transfer drive motor speed diagram (indicated by d in FIG. 4).

The transfer paper P is returned to a predetermined position at high speed (time t5), and at time 5, a signal b is output and the transfer drive motor starts normal rotation again. Further, at time L3, a signal y is output to the high voltage circuit for paper adsorption, and only while the transfer drive motor is rotating at high speed in reverse, the charge remover/charger 33 performs corona charging with a predetermined polarity, and the dielectric belt is 17 and the entire surface of the transfer paper P to prevent the paper position from shifting during high-speed conveyance.

Thereafter, the M image is similarly transferred to the transfer paper P by time 7, and the C image is transferred by the same time L9.

Subsequently, at least from the beginning of the final transfer step.

Transfer of the Bk image is started at time tll, which is set before the leading edge of the transfer paper reaches the position of the charge remover/charger 33, and the yl signal is outputted to the charge remover/charger 33.
Until time 13, a charge-eliminating corona is generated, and only the leading edge of the passing transfer paper P is charge-eliminated and separated from the dielectric belt 17.

Further, at the time mark 13, the paper path switching signal 1 is outputted for a predetermined period of time, specifically, until before the transfer of the Y image to the second sheet of transfer paper P is completed, and the paper path switching signal 1 is outputted to the path switching member 35 and removed. - The charger 33 is moved to the position shown by the dashed line in FIG. 3 by a moving means (not shown).

Therefore, the transfer paper 1] (indicated by the two-dot chain line in FIG. 3) undergoing the fixing process in the fixing means 37 does not come into contact with the charge remover/charger 33, and is therefore free from stains and jams caused by unfixed toner. Occurrence is prevented.

FIG. 5 shows another embodiment of the route switching member 35, in which the route switching member 35a is provided with a transport function so that the transfer paper can be transported smoothly. .

(Effects of the Invention) As explained above, according to the present invention, when the transfer material is conveyed to the fixing means, the functional means is separated from the conveyance path, so that the transfer material can be safely and reliably fixed. The image forming apparatus can be conveyed to a transfer means, and has the unique effect of being able to provide a transfer image without staining and reducing the causes of jams in the image forming apparatus.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a color copying apparatus according to the present invention, FIG. 2 is a block diagram showing the configuration of the electrifying/charging device, and FIG. 23 is a schematic diagram showing the operation of the path switching member and the electrifying/charging device. FIG. 4 is a timing chart of the operation shown in FIG. 3, and FIG. 5 is a schematic diagram showing another configuration of the path switching member.

Claims (1)

[Scope of Claims] An image forming apparatus in which a transfer material is reciprocated with respect to a transfer means to transfer an image, and then the transfer material is conveyed to a fixing means to fix the image, the reciprocating transfer material being transferred to a fixing means. A functional means that functions on the material and is configured to be movable, and when the transfer material moves back and forth, the transfer material is guided to a predetermined path during the transfer process, and the transfer process is completed. An image characterized by comprising a guide means for guiding the transfer material to the fixing means when the material is guided to the fixing means when the material is guided to the fixing means, and a separating means for moving the functional means to separate it from the guide path when the transfer material is guided to the fixing means by the guide means. Forming device.