JPH0331970Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a wet-type image forming apparatus, and more particularly, the present invention relates to a wet-type image forming apparatus applicable to a wet-type image forming apparatus equipped with a developing device or a cleaning device having a developer pan. It is related to.

(Prior art) In a so-called wet image forming apparatus that employs a wet developing method in which a developing solution is supplied to the circumferential surface of a photoreceptor drum carrying an electrostatic latent image to make it visible, the area around the photoreceptor drum is A developing device and a cleaning device are arranged in the .

In FIG. 3 illustrating an example of a developing device, reference numeral 1 designates a photosensitive drum, which rotates in the direction of the arrow during image formation. A developing device 3 covered with a casing 2 is arranged close to the circumferential surface of the photosensitive drum 1 corresponding to the first and fourth quadrants.

Inside the casing 2, a first developing roller 31, a second developing roller 32, and a quiz roller 33 are each rotatably supported. Each roller is made of metal, and the photosensitive drum 1 is rotated for a predetermined period of time.
and are rotated in the directions of the arrows by a drive device (not shown).

Each roller has a casing 3 attached to its base end.
The free ends of the scrapers 34, 35, and 36 fixed to the rollers are pressed against each other to scrape off the developer adhering to the roller surface.

A developer socket 4 is located above the first developing roller 31.
is installed. The developer G supplied from this socket 4 is transferred to the scraper 34 and the first developing roller 31.
The latent image is collected between the rollers and is supplied to the latent image carrier on the surface of the photosensitive drum 1 by the roller rotating in the direction of the arrow.

The developer remaining on the surface of the first developing roller 31 is scraped off by the scraper 34 and collected between the second developing roller 32 and the scraper 35, and is again supplied to the photosensitive drum 1 by the roller 32. be done. The developer remaining on the surface of the second developing roller 32 is scraped off by the scraper 35 and flows down toward the developer receiving pan 37 below the casing 3 .

Excess developer remaining on the surface of the photoreceptor drum 1 during the development process is scraped off by the squeeze roller 33 and flows down into the developer receiving pan 37. The developer that has flowed down to the lower end is discharged through the outlet 38.

Here, the opposite end of the developer tray 37 to the photoreceptor drum 1 is connected to the photoreceptor drum 1 as shown in the figure.
It is set close to the lower end of the developer tray 37 and inclined to draw the developer into the developer receiver tray 37.
Despite this, the liquid existing on the squeeze roller 33 gets twisted and flows out, causing a drip along the outer periphery of the photoreceptor drum 1 to the outside of the casing 3.

This liquid drips onto the transfer paper located below, causing problems such as staining the recorded image surface and staining the inside of the machine.

On the other hand, the cleaning device 9 that cleans the circumferential surface of the photosensitive drum 1 that has passed through the developing device is installed in the fourth cleaning device 9.
As shown in the figure, it is installed on the peripheral surface of the photosensitive drum 1 corresponding to the second development area. The cleaning device 9 includes a casing 77 that is detachably attached to the device body 76, a cleaning roller 79, a cleaning blade 80, and a squeezing roller 8 that are attached to the device body via a bracket 78.
1, a cleaning liquid diffusion plate 82, and a cleaning liquid socket 40.

The bracket 78 is swingably supported by a shaft 83, and after the cleaning operation is completed,
It is swung clockwise about the shaft 83 by means not shown.

The cleaning roller 79 is a roller made of an elastic material having liquid absorbing properties, such as sponge, and
It is rotationally driven by a drive mechanism (not shown).

The cleaning blade 80 is made of rubber or a rubber-like material. During the cleaning operation, the blade 80 brings its free end into pressure contact with the surface of the photoreceptor drum 1, and the cleaning roller 79 elastically deforms its peripheral surface and brings it into pressure contact with the surface of the photoreceptor drum 1. .

While the cleaning blade 80 and the cleaning roller 79 are in pressure contact with the circumferential surface of the photosensitive drum 1, the roller 79 is largely deformed by the squeezing roller 81. Squeezing roller 8
1 is rotationally driven by a drive mechanism (not shown), and squeezes out the cleaning liquid sucked by the cleaning roller 79.

A scraper 84 is brought into pressure contact with the squeezing roller 81 for scraping off cleaning liquid adhering to the circumferential surface thereof. Below the socket 40, the cleaning liquid G' is applied to the cleaning roller 7.
There is a cleaning liquid diffusion plate 82 for dispersing the cleaning liquid in the longitudinal direction of the axis of 9. This diffusion plate 82 is rotatable by a shaft 82a provided at its base edge, and its free side edge is moved by the cleaning roller due to its own weight. It is brought into contact with the circumferential surface of 79.

The free side edge 82b is slightly raised to form a pool of cleaning liquid.

During cleaning, the free side edge of the cleaning liquid diffusion plate 82 is lower than its base side edge.

At the lower end of the casing 77, the casing 77
There is a developer receiver tray 77b and an outlet 41 for collecting the cleaning solution supplied to the developer.

Cleaning roller 79 when not cleaning
The cleaning blade 80 swings around the shaft 83, but at this time, the cleaning roller 7
9 is spaced apart not only from the surface of the photoreceptor drum 1 but also from the aperture roller 81 to prevent deformation, and also allows the cleaning liquid diffusion plate 82 to be separated from its free side edge 82b.
Rock so that the base edge is higher than the base edge. In this process, the cleaning liquid diffusion plate 82
The upper developer flows down from the free side edge 82b. For example, the liquid is divided into two types: one that flows along the circumferential surface of the photoreceptor drum 1, and one that flows along the developer tray portion 77b, and there is also a small amount that scatters.
Particularly, when copying is performed intermittently one by one, the switch is repeatedly turned on and off, which causes the supply of developer from the socket 40, the swinging of the cleaning liquid diffusion plate 82, the cleaning roller 79, and the photoreceptor. The number of times the drum 1 comes into contact with the drum 1 increases, and as shown in FIG. It will make it dirty.

(Objective) Accordingly, an object of the present invention is to provide a wet image forming apparatus that can prevent liquid from dripping from the portion of the developer tray facing the photoreceptor drum.

(Structure) In order to achieve the above object, the present invention is characterized in that the end portion of the developer tray portion facing the photosensitive drum has a double structure. The present invention employs a wet development method in which a developing solution is supplied to the peripheral surface of a latent image carrier carrying an electrostatic latent image to make it visible.
A developing device or a cleaning device disposed around the latent image carrier has a developer tray portion below the casing for collecting the developer, and an end portion of the developer tray portion facing the latent image carrier is In a wet type image forming apparatus that is close to the latent image carrier and is inclined so as to draw the developer into the developer receiver, an end portion of the developer receiver that faces the latent image carrier is separated from the other end. It is characterized by having a heavy structure.

The present invention will be specifically described below based on one embodiment of the present invention.

First, an embodiment of a developing device will be described with reference to FIG. This figure corresponds to FIG. 3 in the prior art, and common members are given the same reference numerals. A liquid receiving plate 11 is set on the end of the developer receiving tray 37 facing the photoreceptor drum 1 via a spacer 10, forming a double structure. The distance between the spacers 10 is 1 to 5 mm, and the distance between the liquid receiving plate 11 and the photosensitive drum 1 is also 1 to 5 mm. The spacers 10 are, for example, in the form of pillars, and are arranged at intervals in between, or by removing a part of the plate so that the liquid can flow down between the developer receiving tray 37 and the liquid receiving plate 11. shall be.

When an experiment was conducted with this configuration, no dripping of the developing solution (viscosity 1.05 to 2.25 cp, 25° C.) occurred.

Next, as a measure against dripping in the cleaning device, as shown in FIG. 2, the end of the developer receiving tray 77b facing the photoreceptor drum 1 is made to have a double structure in accordance with the above example. In other words, the developer tray portion 77b
A liquid receiving plate 13 is placed on top via a spacer 12 similar to the spacer 10 in the above example to form a double structure. Here, the distance between the spacers 12 is 1 to 5 mm, and the distance between the tip of the liquid receiving plate 13 and the photosensitive drum 1 is 1 to 2 mm.

When comparing this configuration with the conventional example shown in Figure 4, it was found that in the conventional example, after the operation of making one copy with one on/off switch was repeated 100 times, liquid dripped and the transfer paper was damaged. An abnormal image was generated, and the transfer paper separation unit located below became dirty. In comparison, with the above configuration, no liquid drips at all under the same switch on/off conditions, and even after the switch was turned on and off 3000 times, no liquid drip abnormalities occurred at all. We were also able to completely prevent dirt inside the aircraft.

(Effects) In the present invention, the part where liquid drips conventionally occurs has a double structure to prevent liquid dripping, and it is possible to prevent abnormal images, stains inside the machine, etc. due to liquid dripping.

[Brief explanation of the drawing]

FIG. 1 is a front view illustrating the main parts of the developing device according to the present invention, FIG. 2 is a front view illustrating the main parts of the cleaning device according to the present invention, and FIG. 3 is a front view of the developing device according to the prior art. FIG. 4 is a front view of a cleaning device according to the prior art. 1... Photosensitive drum, 37, 77b... Developing solution tray section, 10, 12... Spacer, 11, 13...
...Liquid receiving plate.

Claims (1)

[Scope of Claim for Utility Model Registration] A wet developing method is adopted in which a developing solution is supplied to the peripheral surface of a latent image carrier carrying an electrostatic latent image to visualize the image, and the area around the latent image carrier is The developing device or cleaning device has a developer tray portion disposed below the casing for collecting the developer, and an end portion of the developer tray portion facing the latent image carrier is close to the latent image carrier. The wet image forming apparatus is tilted so as to draw the developer into the developer tray, characterized in that an end of the developer tray facing the latent image carrier has a double structure. Wet-type image forming apparatus.