JPS59105665A - Developing and liquid draining system in electrophotographic device - Google Patents

Abstract

PURPOSE:To enable simplification in the construction of a conveyance system by spraying a toner onto a photosensitive surface by the pressure of gas for liquid draining to be ejected onto the photosensitive surface. CONSTITUTION:When a valve 1 is opened, the toner 14 in a storage part 18a is forced by the pressure of the gas supplied from a supply source 23 for pressurized gas toward a developing head 11. As a result, the toner 14 is sprayed through an aperture 12a to a photosensitive surface 13a whereby said surface is developed. The gas successively flowing into the head 11 is thereafter ejected similarly through the aperture 12a to the surface 13a, whereby squeezing is accomplished. The excess toner 14 is returned into a tank 15 through a flow passage 20 and similarly the gas used for squeezing is returned into the tank 15 and is released into the atmosphere through the cover 15b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developing and liquid draining system in an electrophotographic apparatus, and is an attempt to simplify the structure thereof.

Unlike photographic film, which uses silver salt photographic materials as photoreceptors, electrophotographic materials have a long life as photosensitive materials, taking advantage of the feature that they can be reused by cleaning them after development and before fixing, regardless of whether they are exposed or not. A roll film is used to record an image by partially charging, exposing, developing, and fixing, and the resulting image is not transferred to an IC.
It is used in microfilm, etc., which is used for purposes such as projection along with recorded parts, and then additional records are added to the unrecorded parts.

Among electrophotographic devices using microfilm, so-called wet-type devices that develop electrostatic latent images with liquid toner require charging, exposure, development, drying, and fixing to be performed for each frame. During processing, it is desirable that toner not overflow or ooze out of areas other than the area of the photosensitive incline to be processed, and excess developer should be removed before separating the photosensitive material from the developing section and moving it to another processing section. It is necessary to drain the liquid (hereinafter referred to as quenching) to remove it.

FIG. 1 shows an example of a developing and draining system in a conventional electrophotographic apparatus using a wet type vacuum pump. As shown in the figure, this type of developing head 1 is equipped with a mask 2, and this mask 2 has an opening 2a with a width corresponding to one frame of the photosensitive surface 3, and an opening end 2b of the mask 2. It is in contact with the photosensitive material 3. As a result,
One frame of the photosensitive material 3 faces the photosensitive surface Ba1d opening D2a, and liquid toner 4 is applied to the photosensitive surface 3 through this opening 2a.
A predetermined latent image is developed by spraying onto a. Following this development, the toner 4 adhering to the photosensitive surface 3a is removed, and this squeezing is similarly performed by blowing a gas such as air onto the photosensitive surface 3a through the opening 2a. Therefore, it is necessary to transport the liquid toner 4 and gas (air in this example) to the opening 2a, but this transport involves sucking up the liquid toner 4 stored in the tank 5 with the vacuum pump 6, and also using the valve 7. By opening, air is similarly sucked in from the air by the vacuum pump 6. The surplus toner 4 after the spraying and development and the air after squeezing are returned to the tank 5. That is, there is a flow path 8 that extends from the tank 5 to the inside of the developing head 1 and communicates with the opening 2a, and an end that is open to the atmosphere passes through the valve 7 to the inside of the developing head 1, and the flow is connected upstream of the opening 2a. Along with a flow path 9 that joins the flow path 8, a flow path 10 is formed which extends from the opening 2a to the outside of the developing head 1, passes through the vacuum pump 6, and returns to the tank 5.

Thus, in the developing and draining system of this type of electrophotographic apparatus, the photosensitive surface 3 is blown by toner 4 =:1.
After the development and squeezing of step a, the next step is the drying and fixing process.In the above system, the vacuum bonder 6 is used as the conveyance system for the toner 4 and squeeze gas, so the structure of this part is has become complex and expensive.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, it is an object of the present invention to provide a developing and liquid draining system for an electrophotographic apparatus that can simplify the structure of a transport system. The present invention that achieves this object has the following features: After development by spraying liquid toner onto the photosensitive surface, the toner can be blown onto the photosensitive surface using the pressure of a liquid draining gas that is similarly blown onto the photosensitive surface. This is the basis of its technical philosophy.

Embodiments of the present invention will be described in detail below based on the drawings. As shown in FIG. 2, the developing head 11 of this embodiment is also equipped with a mask 12, similar to the prior art described above, and this mask 12 has an opening 1 having a width corresponding to one frame of the light material 13.
2a, and its open end 12b is a photosensitive material 13.
is in contact with As a result, one frame of the photosensitive surface 13a of the photosensitive material 13 faces the opening 12a, and by spraying the liquid toner 14 through the opening 12a, a predetermined latent image is developed. Then, air is blown onto the photosensitive surface 13a to perform squeezing. The tank 15 in which the toner 14 is stored has a discharge port 1 at its bottom.
5a, and communicates with one end of the flow path 18 via the discharge port 15a and the check valve 21. The other end t of this flow path 18 is in communication with the developing head 1 located above the M discharge port 15a. A storage section 1 in which toner 14 is usually collected at a height 1 that is in equilibrium with the surface.
8a is formed. - One end of the flow path 19 is communicated with the reservoir 18a of the flow path 18, and the pressurized gas supply source 2 is connected via a valve 17 and a pressure reducing valve 22 interposed in the middle.
It is connected to 3. Basically, this pressurized gas supply source 231d may be a source that supplies pressurized gas, such as a compressor that compresses air, but considering the simplicity required for this type of electrophotographic apparatus, 6 klf'
Gas cylinders, air pumps, etc. in which freon, propane, etc. are pressurized and sealed at a pressure of d are suitable. The pressure reducing valve 22 reduces the supply gas to a suitable pressure, for example lk! Although it is necessary to reduce the pressure to a certain extent, it is not essential. At this time, the check valve 21 allows the toner 14 to flow out from the tank 15 into the channel 18, but prevents the toner 14 from flowing into the tank 15 from the channel 18. On the other hand, the flow path 2o is for circulating the excess toner 14 and air from the opening 12a to the tank 15, and its outlet opening end is connected to the tank 15.
It opens toward the storage surface of the toner 14 inside and is at atmospheric pressure.

Therefore, when the valve 17 is opened, the toner 14 in the storage section 18a is pressed toward the developing head 11 by the pressure of the gas supplied from the pressurized gas supply source 23. As a result, opening 1
The toner 14 is sprayed onto the photosensitive surface 13a through the opening 12a for development, and the gas subsequently flowing into the developing head 11 is similarly sprayed onto the photosensitive surface 13a through the opening 12a, thereby performing squeezing.

The excess toner 14 is returned to the tank 15 via the flow path 20, and the squeezed gas is also returned to the tank 15 and released to the atmosphere via the lid 15b'i. This lid 15b
Normally, due to its own weight, the exhaust port 15d formed in the airtight lid 15C of the tank 15 is blocked, and when the gas pressure acts from below, it floats upward, opening this area and releasing the gas into the atmosphere. It is something that allows you to escape. The reason why the tank 15 is normally made into a sealed structure is to prevent the toner 14 from being exposed to the air, that is, to prevent the toner 14 from drying out and from getting dust mixed into the toner 14.

In this embodiment, by opening the valve 17, the storage section 1 is
The toner 14 accumulated on the surface of the toner 8a is blown onto the photosensitive surface 13a, and this creates a gap between the open end 12b and the photosensitive surface 13a. As a result, the inside of the developing head 11 becomes atmospheric pressure, and as a result, the toner 14 flows out from the inside of the tank 15 through the check valve 21, and the toner 14 is stored in the storage portion 18a to a height corresponding to the upper surface of the toner 14 inside the tank 15. , from then on the action of the same rod is repeated. At this time, the opening end 12b is connected to the photosensitive surface 1.
Since the open end of the flow path 20 is open to the atmosphere even though the flow path 3a is sealed, the toner 14 is promptly stored again as described above.

As explained above in detail with the embodiments, according to the present invention, the toner for development can also be conveyed by the squeeze gas, so there is no need for special equipment such as a pump for conveying the toner. The structure is simplified.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram conceptually showing a developing and liquid draining system according to the prior art, and FIG. 2 is an explanatory diagram conceptually showing an embodiment of the present invention. In the drawing, 11 is a developing head, 12a is an opening, 13 is a photosensitive material, 13a is a photosensitive surface, 144-Il, 15 is a tank, 15a is an outlet, 17 is a valve, 18, 19, 20 is a flow 18a is a reservoir, 21 is a check valve, and 23 is a pressurized gas supply source. Patent applicant Fuji Photo Film Co., Ltd. Representative Patent attorney Shibe Mitsuishi (and 1 other person)

Claims (1)

[Claims] The toner is transported from a tank storing liquid toner to a developing head, and the latent image is developed by spraying the toner onto the photosensitive surface through an opening of the developing head facing the photosensitive surface of the electrophotographic device. In a developing head of an electrophotographic device, surplus toner during development is returned to the tank, and the toner is sprayed onto the photosensitive surface to remove the toner liquid, between the outlet of the tank and the developing head. a flow path that communicates with the flow path and has a storage section in which toner is normally stored from the discharge port to a height corresponding to the liquid level of the toner stored in the tank; and this flow path and the discharge port. a check valve that is interposed between the tank and the tank and allows the toner to flow out from the tank to the flow path, but prevents the toner from flowing into the tank from the flow path;
On the side of the development head from this check valve, there is a flow path, one end of which communicates with the storage portion of the flow path, and the other end of which communicates with the pressurized gas generation source via the valve, and a flow path that contains excess toner and liquid after development. A developing and draining system for an electrophotographic apparatus, characterized by having a flow path that returns gas after cutting to a tank and is open to atmospheric pressure.