JPH02244172A - Developing device of electrophotographic type recorder - Google Patents

Abstract

PURPOSE:To prevent the contamination in a device body and the generation of a bearing lock by closing the space enclosed by the surface of a layer thinning roller, the front end face of a scraper and sealing members with a sealing body to prevent a toner from leaking along the layer thinning roller to both axial sides thereof. CONSTITUTION:The toner 34 on the surface of a developing roller 26 is formed to a thinner layer by the layer thinning roller 29 and the toner sticking thereto is scraped off by a scraper 32. The sealing members 38 are pressed to both axial ends of the scraper 32 and both axial ends of the layer thinning roller 29 to prevent the leakage of the toner therefrom. The sealing body 42 which closes the space A enclosed by the surface 29a of the layer thinning roller 29, the front end face 32a of the scraper 32 and the sealing members 38 to prevent the leakage of the toner to both axial ends along the layer thinning roller 29 is provided in a casing. The space A is closed by the sealing body 42 to prevent the leakage of the toner to both axial sides of the layer thinning roller 29, by which the generation of the bearing block is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention can be applied to electrophotographic recording devices that record using an electrophotographic method, such as laser printers, laser copying machines, and laser facsimiles. Specifically, in such electrophotographic recording devices.

Adhering toner to the photoreceptor 1. The present invention relates to a developing device that develops an electrostatic latent image on the surface of the photoreceptor into a visible image.

Conventionally, in this type of developing device, as shown in FIGS. 6 and 7, toner 2 is placed on the photoreceptor 1 in the developing chamber d.
a developing roller 3 that adheres to the electrostatic latent image on the surface of the photoreceptor 1 to make it visible; a thinning roller 4 that thins the toner 2 on the surface of the developing roller 3; and a thinning roller that thins the toner 2 on the surface of the developing roller 3. A rectangular and flat scraper 5 is provided to scrape off the toner 2 adhering to the toner 4.

By the way, in this type of developing device, if the toner 2 leaks from both sides of the developing roller 3 and the layer thinning roller 4 in the axial direction,
There was a risk that the inside of the apparatus would be contaminated and that the toner 2 would enter the bearing 6 that supports the developing roller 3 and the bearing 7 that supports the thinning roller 4, causing so-called bearing lock.

For this reason, conventionally, a sponge type or flocked type seal member 8 is attached to the casing 9.

The tip of the sealing member 8 was pressed against both axial ends of the developing roller 3 and the layer thinning roller 4 and both widthwise ends of the scraper 5 to form a sealing area S there.

However, in this type of conventional developing device, as shown in FIG. This creates a problem in that toner leaks through the space a and along the thinning roller 4 to both sides in the axial direction.

SUMMARY OF THE INVENTION An object of the present invention is to solve such conventional problems in a developing device of an electrophotographic recording apparatus and to prevent toner from leaking to both sides of the thinning roller in the axial direction.

Therefore, in the present invention, for example, as shown in the illustrated embodiment below, a toner 34 is attached to a photoreceptor 13 and an electrostatic latent image on the surface of the photoreceptor 13 is visualized by a developing roller 26,
The toner 34 on the surface of the developing roller 26 is thinned by the roller 2.
9, the toner 34 adhering to the thinning roller 29 is scraped off with a scraper 32.
Both ends in the width direction and the thinning roller 2 facing thereto
A developing device 16 of an electrophotographic recording device in which a sealing member 38 is applied to both axial ends of the developing device 9 to prevent toner from leaking therefrom.
In this case, the space A surrounded by the surface 29a of the thinning roller 29, the tip end surface 32a of the scraper 32, and the sealing member 38 is closed, and the toner leaks along the thinning roller 29 to both sides in the axial direction. The casing 21 is characterized by being provided with a seal body 42 for preventing this.

Run--1 Then, with the seal body 42, the surface 29 of the thinning roller 29
A, the space A surrounded by the tip surface 32a of the scraper 32 and the sealing member 38 is closed to prevent toner from leaking to both sides of the thinning roller 29 in the axial direction.

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 5 shows a schematic configuration of a laser printer equipped with a developing device according to the present invention. In FIG.
Reference numeral 1 denotes a paper feed cassette provided in the printer main body 10. Paper 5 fed from the paper cassette 11 in the direction of arrow A
0 is conveyed to a drum-shaped photoreceptor 13 at the correct timing by a pair of registration rollers 12 . The photoreceptor 13 is
This latent is rotated clockwise, the surface is uniformly charged by the charging charger 14, and an electrostatic latent image is formed on the photoreceptor 13 by irradiating the laser beam from the laser optical system 15. When the image passes through the developing device 16 according to the present invention, it becomes visible with toner, and this visible image is transferred by the transfer charger 17 to the paper 50 conveyed to the photoreceptor 13.
The visible image on the transferred paper 50 is a fixing device! Fixed by 18. And fixing equipment! The paper 50 that has come out of the paper 18 is discharged, for example, to paper discharge sections 19 in the direction of the arrow. on the other hand,
A cleaning device 20 removes residual toner from the photoreceptor 13 after the visible image has been transferred.

The above-mentioned developing device 16 is constructed as shown in FIGS. 3 and 4, and 21 in FIG. 9 is a casing. A developing chamber 23 having an opening 22 on the side of the photoreceptor 13 and a toner supply chamber 25 having an opening 24 above are formed therein. A developing roller 26 that applies toner to the latent image on the photoreceptor 13 is housed in the developing chamber 23 . Both ends of the shaft 27 of the developing roller 26 are supported via bearings 28 . In addition, in the developing chamber 23, a toner layer of 10 to 20 μm is applied to the surface of the developing roller 26 by pressing it against the developing roller 26.
A thinning roller 29 for thinning the layer is housed and arranged. Both ends of the shaft 30 of the thinning roller 29 are supported via bearings 31. moreover.

A scraper 32 is housed in the developing chamber 23 for cleaning by pressing the tip against the surface of the thinning roller 29 and scraping off toner adhering to the thinning roller 29 . The base end of the scraper 32 is.

It is fixed to the casing 21 with screws 33.

The toner supply chamber 25 houses toner 34, and also houses an agitator 35 for stirring the toner 34 and a replenishment roller 36 for feeding the toner 34 to the developing roller 26. Further, in the opening 24 of the toner supply chamber 25,
A toner cartridge 37 for replenishing toner 34 is attached replaceably.

By the way, in the developing device 16 according to the present invention.

A sealing member 38 is pressed against both ends of the developing roller 26 and the layer thinning roller 29 in the axial direction and both ends of the scraper 32 in the width direction, in contact with each other on the side opposite to the photoreceptor 13,
A sealing area S is formed. The sealing member 38 consists of a sponge seal 39 and a flocked seal 40, each of which is attached to the casing 21 using double-sided tape or the like.

and.

The sponge seal 39 is made of foamed polyurethane, felt, etc., and
Contact with 2. On the other hand, the flocked seal 40 is made of Teflon fiber, for example, and contacts the thinning roller 29 and the developing roller 26 . Thus, both ends of the thinning roller 29 in the axial direction and both ends of the scraper 32 in the width direction are reliably sealed with the highly airtight sponge seals 39. In addition, both axial ends of the thinning roller 29 and the developing roller 26 are
A flexible flocked seal 40 securely seals both rollers without increasing their rotational torque.

Now, a developing device like this! 16, as shown in FIG.
At a position surrounded by the distal end surface 32a and the seal member 38,
Space A is created in the same way as before.

However, the developing bag according to this invention! ! At step 16, as shown in FIG. 1, the space A is closed and a sealing body 42 is provided. The seal body 42 is made of, for example, a polyester film, and is attached to the side plate 21a of the casing 21 (see FIG. 4).
I support it.

Then, the space A is closed with the seal body 42.

Toner leakage along the thinning roller 29 to both sides in the axial direction is prevented.

Therefore, according to the present invention, the space surrounded by the surface of the thinning roller, the tip surface of the scraper, and the sealing member is closed with the sealing member, and the toner is prevented from flowing along the thinning roller. Since it prevents leakage to both sides in the axial direction, it is possible to prevent the inside of the recording device from becoming dirty and from bearing lock.

[Brief explanation of drawings]

FIG. 1 is an enlarged view of essential parts of a developing device which is an embodiment of the present invention, FIG. 2 is a further enlarged view of the main part, FIG. 3 is a sectional view of the developing device, and FIG. - IV line arrow view,
FIG. 5 is a schematic configuration diagram of a laser printer equipped with the developing device, FIG. 6 is a sectional view of a conventional developing device, and FIG.
8 is a partially enlarged view of FIG. 6. 13...Photoreceptor 21...Casing 26...Developing roller 29...Thinning roller 29a ...Surface 32 of the thinning roller...
... Scraper 32a ... Scraper tip surface 34 ...
......Toner 38...Seal member 42...Seal body A...Space

Claims (1)

[Claims] Toner is attached to a photoreceptor, the electrostatic latent image on the surface of the photoreceptor is visualized with a developing roller, the toner on the surface of the developing roller is made into a thin layer with a thinning roller, and the toner is adhered to the thinning roller. In a developing device of an electrophotographic recording device, the toner is scraped off with a scraper, and a sealing member is applied to both widthwise ends of the scraper and both axial ends of the thinning roller opposing the scraper to prevent toner from leaking therefrom, A sealing body that closes a space surrounded by the surface of the thinning roller, the tip end surface of the scraper, and the sealing member to prevent toner from leaking along the thinning roller to both sides in the axial direction; A developing device for an electrophotographic recording device, which is installed in a.