JPS6024466B2 - electrophotographic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an image-forming particle dispersion device for an electrophotographic apparatus, and in particular, image-forming particles are electrostatically deposited on the surface of a photoreceptor containing a photoconductive substance, etc. The surface and the image forming particles are exposed imagewise to reduce or eliminate the charge in the light irradiated area of the photosensitive surface, and the image forming particles whose electrostatic attraction between the photosensitive surface has been reduced or eliminated are removed from the photosensitive member. ,
It is an object of the present invention to provide an electrophotographic apparatus that is particularly effective in an electrophotographic system in which an image is formed using residual particles.

Another object of the invention is to reduce the consumption of the imager particles.

In this type of electrophotographic apparatus, in order to obtain a clear image with good resolution and no fog, it is necessary to electrostatically adhere image forming particles evenly and densely to the surface of the photoreceptor before image exposure.

Conventionally, a method shown in FIG. 1 has been proposed as a scattering device for electrostatically depositing image forming particles onto the surface of a photoreceptor.

In FIG. 1, when a photoreceptor b is charged by a charger a, a gate d of a hopper c is opened, and image forming particles e are scattered onto the photoreceptor. However, in this case, in order to make the image forming particles densely adhere to the photoreceptor b, it is necessary to discharge a large amount of the image forming particles from the gate d, and most of them are collected in the collection housing f, and the image forming particles consumption will increase. Furthermore, when the photoreceptor is transported at high speed, the spraying ability is significantly reduced. In order to reduce the amount of image forming particles consumed, a method has also been proposed in which the image forming particles that have fallen into the collection housing f are returned to the hopper c using a circulation means. As a result, the image forming particles are damaged, resulting in poor light transmittance and electrical conductivity of the image forming particles, causing fogging in the image after development. In view of the above-mentioned prior art, the present invention provides a dispersing device that can adhere image forming particles densely to a photoreceptor, can spray the image forming particles without damaging them, and can sufficiently follow the traveling speed of the photoreceptor. This is what we provide.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A color electrophotographic apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 2, a belt-shaped photoreceptor 1 is supported under tension by a driving roller 2 and supporting loaves 3, 4, and 5. As shown in FIG. A spraying device is arranged on the side of the charger 6 in the traveling direction of the photoreceptor 1. The image forming particle dispersing device includes a holding means 8 for holding image forming particles rotatably supported on a shaft 7, a supply means 10 for supplying image forming particles 9 to the holding means 8, and a holding means 8 for distributing image forming particles onto the photoreceptor 1. It consists of a layer-forming means for forming image-forming particles attached in multiple layers into a single layer. As shown in FIG. 3, the holding means 8 is connected to a solenoid 11 attached to a side plate (not shown) via a bar 12.

The lever 12 is connected to the solenoid 11 by pins 13 and 14.
and is rotatably attached to the holding means 8. A positioning pin 15 is fixed to the shaft 7 and determines the resting position of the holding means 8 when the image forming particles 9 are dispersed by hitting the stopper 16 extending from the side plate.

The holding means 8 is normally stopped by the positioning pin 15 hitting the stopper 17 at a position where the electrostatic force of the photoreceptor 1 does not reach the image forming particles on the holding means 8. After the image forming area of the photoreceptor 1 is charged by the charger 6, the solenoid 11 is energized only when passing through the spraying section A, and the solenoid 11 approaches the photoreceptor 1 as shown in FIG.

At this time, a part of the holding means 8 may come into contact with the photoreceptor 1.
The supply means, generally indicated by 10, is composed of a diaphragm 19 having a vibrator 18 fixed at one end, a hopper 20 for the image forming particles 9, and a gate 21 for adjusting the supply amount of the image forming particles.

The layering means consists of a vibrating roller 22 and a suction box 23. The vibration roller 22 has a projection at at least one location on its outer periphery, is provided so that at least the projection comes into contact with the back surface of the photoreceptor 1, and is rotated by a rotating means (not shown). The image forming particles 9 are attached to the photoreceptor 1 by the holding means 8, and at this time, due to the electrostatic force of the photoreceptor I or the adhesive force between the image forming particles 9, they are stacked in two or more layers and attached to the photoreceptor 1. However, compared to the first layer of image forming particles that are in direct contact with the photoreceptor, the adhesion force of the second and higher layers of image forming particles stacked on top of other image forming particles is extremely 4.degree. Therefore, by vibrating the photoreceptor 1 by vibrating the back surface of the photoreceptor 1 with the vibrating roller 22, the image forming particles of the second and higher layers can be dropped from the photoreceptor 1. Further, the strength of the vibration applied to the photoreceptor 1 can be changed by adjusting the rotation speed of the vibration roller 22, the size of the protrusion, and the tension of the photoreceptor 1. It is sufficient to check the adhesion state of the image forming particles on the photoreceptor 1 and set them so that the image forming particles form a single layer on the photoreceptor 1. 2
4 is a collection housing for image forming particles.

The image-forming particles 9 stored in the hopper 20 contain a heat-sublimable dye that develops a yellow color, light-transmissive image-forming particles that transmit blue-violet light, and a heat-sublimable dye that develops a magenta color. It is a mixture of light-transmitting image-forming particles that transmit green light and light-transparent image-forming particles that contain a heat-sublimable dye that develops cyan and transmit red light.

The color original 25 is placed on a transparent support 26, and an optical system is composed of the support 26, a light source 27, reflecting mirrors 28, 29, a lens 30, and a slit 31.
The light combined at step 7 is reflected by the color original, and is irradiated onto the photoreceptor 1 and the image forming particles passing under the slit 31 along the path shown by the dotted line L, thereby performing an image exposure.

The developing device is composed of a vibrating roller 32 and a suction box 33, and the vibrating roller 32 has a projection at at least one location.
At least a protrusion is disposed on the back surface of the photoreceptor 1 and rotated by a rotation means (not shown). The receiving sheets 34' are stored in the paper feed tray 35, and the uppermost receiving sheet is in contact with the feed-out roller 36. 37 and 38 are paper guides provided before and after the transfer roller 39.

The transfer roller 39 is pressed against the photoreceptor 1 with a predetermined pressure. The fixing device 40' heats the image forming particles transferred onto the receiving sheet by the transfer roller 39 to obtain a colored image of the sublimable dye contained in the image forming particles on the surface of the receiving sheet. A cleaning device 41 removes image forming particles slightly remaining on the photoreceptor 1 after transfer.

If a copy button (not shown) is now pressed, the photoreceptor 1 begins to be transported in the direction of arrow N and is given an electrostatic charge by the charger 6.

When the charged image forming area of the photoreceptor 1 reaches the scattering section, the holding means 8 approaches the photoreceptor 1 as shown in FIG. At the same time, the vibrator 18 is activated, and the image forming particles on the diaphragm 19 are supplied to the holding means 8. Some of the image forming particles supplied to the holding means 8 fall into the collection housing 24, but most of the image forming particles are accumulated in the holding means 8 in a dense state with no gaps between them, and are not connected to the photoreceptor 1. Since the contact area with the image forming particles is large, even if the photoreceptor 1 is traveling at high speed, the image forming particles are attached to the photoreceptor 1 without any gaps between them.
Attach to. In the scattering section A, the image forming particles are attached to the photoconductor 1 in two or more layers, so by vibrating the back surface of the photoconductor 1 with the vibrating roller 22, the image attached to the first layer is removed. A force that is not sufficient to remove the forming particles but sufficient to remove particles attached to two or more layers is applied to the image forming particles to form a single layer of image forming particles. In addition,
The vibration roller 22 has the same shape as the vibration roller 32 described above, and is disposed on the back surface of the photoreceptor 1 so that at least a protrusion supports the vibration roller 22 . The image forming particles removed here are stored in the suction box 2.
I am attracted to 3. In the image forming area of the photoreceptor 1 on which the image forming particles are adhered in one layer by the single layer forming means, the image forming particles and the photoreceptor are irradiated with light at the position of the slit 31, and the image forming particles are separated according to the color of the color original 25. Light passes through the photoreceptor, and the electrostatic charge is reduced or eliminated in the area of the photoreceptor to which the image-forming particles through which the light has passed are attached.

Next, the vibrating roller 32 vibrates the back surface of the photoconductor 1 to remove the image forming particles whose electrostatic attraction between the photoconductor 1 has been reduced or removed from the photoconductor 1, and the remaining particles form an image. form. The image created by the remaining particles is then transferred. The image is transferred onto the receiving sheet 34 by the roller 39. After the transfer, the receiving sheet 34 is conveyed to the fixing device 40, and the color image is discolored by the heat sublimable dye contained in the image forming particles. In addition, in the above embodiment, the vibration roller 22 and the suction box 2
3 constitutes a layering means, but the suction box is not necessarily necessary, and the image forming particles removed from the photoreceptor 1 by the vibrating roller 22 are allowed to fall down the slope formed by the photoreceptor 1 and onto the holding means 8. You can store it in

As described above, in the electrophotographic apparatus of the present invention, since the contact area between the photoreceptor and the group of image forming particles is large, even when the photoreceptor is transported at high speed, it is possible to sufficiently follow and scatter the image forming particles. can.

In addition, since the holding means is brought close to or in contact with the photoreceptor only when the image forming area of the photoreceptor passes through the scattering section, the image forming particles are not scattered outside the image forming area and the amount of image forming particles consumed is reduced. It has the advantage of being easy to use.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a conventional image forming particle dispersion device;
FIG. 2 shows the structure of an embodiment of the electrophotographic apparatus of the present invention, and FIG. 3 shows the structure of the image forming particle dispersion device. 1... Photoreceptor, 6... Charger, 8... Holding means, 9...
Image forming particles, 10... Particle supply means, 22...
・Vibration loaf for particle layering. Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. In an electrophotographic apparatus that performs exposure and development after uniformly scattering image forming particles onto a photoreceptor containing a photoconductive substance, a charger close to the photoreceptor and the photoreceptor are provided. a holding means for the image-forming particles that is close to or partially in contact with the body; a particle supply means that supplies the particles to the holding means;
layering means for applying vibration to the photoreceptor to remove image forming particles other than particles directly attached to the photoreceptor from among the image forming particles adhering to the photoreceptor; An electrophotographic apparatus characterized in that a charger, a holding means, and a layering means are arranged. 2. Claim 1, wherein the layering means has a protrusion at at least one location on the outer periphery, and includes a vibrating roller arranged such that at least the protrusion comes into contact with the photoreceptor.
The electrophotographic device described in Section 1.