JPH0434534Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a toner guide plate used in a toner cleaning device of a dry type electronic copying machine.

Generally, a transfer type copying machine uses a rotating drum having a photoconductive photosensitive layer on its outer circumferential surface, and while rotating this drum, an electrostatic latent image is formed on the photosensitive layer, and this is developed by toner. The toner image is transferred to transfer paper.

Thereafter, since toner still adheres to the drum surface after this transfer has been completed, it is necessary to remove this, so the drum is usually rotated in the direction of the arrow around a horizontal axis as shown in Figure 1. A cleaning blade 2 is disposed so that its lower edge abuts the upwardly rising portion of the outer circumferential surface of the rotating drum 1, and this blade 2 relatively slides on the outer circumferential surface of the drum 1. The adhering toner is scraped off by moving.

This scraped toner is collected in the toner collection container 3.
The toner is guided inside by the toner guide plate 4 and collected.

That is, the toner guide plate 4 is arranged to be inclined so that its upper edge comes into contact with the outer peripheral surface of the drum 1 at a position below the blade 2.

This proposal relates to the structure of this toner guide plate, in which the contact surface with the photosensitive drum is made of sheet-like thermoplastic polyurethane, with a thickness in the range of 0.05 to 0.5 mm.
A member made of a resin selected from polyester resin, polyimide resin, polycarbonate resin, and fluororesin, which has a hardness in the range of 70° to 99° on the JIS A scale and has a lower elastic modulus than thermoplastic polyurethane, is layered on thermoplastic polyurethane. It is characterized by the combination.

Conventionally, this type of toner guide plate has been designed to be elastic and have good adhesion to the drum so that no gap is created between it and the drum, and to have a high contact force with the drum so as not to damage the photosensitive layer. Various performances were required, such as being able to be adjusted and having a low coefficient of friction with the toner so that the toner could be smoothly collected into a collection container, but it was not possible to find anything that satisfied all of these requirements.

Conventionally used materials include polyester film (Lumirror manufactured by Toray Industries, Inc.) and synthetic rubber sheets such as thermosetting urethane rubber.

However, although it is possible to maintain a constant thickness of polyester film, for example 0.08 mm to 0.1 mm, it has the disadvantage that it is too stiff and may damage the surface of the photosensitive drum, making it difficult to adjust the pressing force against the drum. .

In addition, synthetic rubber sheets such as thermosetting urethane rubber do not have any problems in terms of waist strength, but it is difficult to maintain a constant thickness, especially if the thickness is thin and uniform (for example, 0.05
mm to 0.5 mm), and due to variations in thickness, the waist strength changes, resulting in variations in the toner collection function.

The present applicant previously filed U.S. Pat.

The contents are hardness JIS A scale 70° to 96°
Made of thermoplastic polyurethane sheet with a thickness of 0.05mm
It is characterized by cutting and molding ~0.5mm to the specified size.

By using this thermoplastic polyurethane sheet, it is possible to mold it into a thin and uniform thickness, which stabilizes the back force against the drum, but it has been found that the back force against the drum decreases when used for a long period of time.

The present invention is a toner guide plate which is a further improvement on the above-mentioned applied product, which prevents the lowering of the waist force against the drum due to long-term use, and which has an excellent toner collection ability. is a thermoplastic polyurethane that is the same as the above-mentioned applied product, but by having a member with a lower elastic modulus than the thermoplastic polyurethane superimposed on the thermoplastic polyurethane, it is possible to make the thermoplastic polyurethane stiffer. The feature is that the contact force is assisted.

The thermoplastic polyurethane used here is in the form of a sheet, and preferably has a thickness in the range of 0.05 mm to 0.5 mm and a hardness in the JIS A scale range of 70° to 99°.

Further, the member having a lower elastic modulus than thermoplastic polyurethane is in the form of a sheet, and the material used is a film sheet selected from polyester resin, polyimide resin, polymamide resin, polycarbonate resin, fluororesin, etc.

In addition, the thermoplastic polyurethane and the low elastic modulus sheet are stacked together using adhesive tape or thermal adhesive tape, and the total thickness is 0.1 mm.
It is preferably in the range of ~2.0mm. The thermoplastic polyurethane sheet and the low elastic modulus sheet may be stacked to have the same width, as shown in FIGS. 2 and 3, or only the thermoplastic polyurethane sheet may have a longer width.

Examples will be described below.

(Example) A thermoplastic polyester resin (Lumirror R manufactured by Toray Industries, Inc.) with a JIS A scale of 90°, thickness of 0.2 mm, width of 30 mm, and length of 280 mm was adhered to a support made of aluminum having a sheet attachment part using adhesive tape. By overlapping them with tape, a toner guide plate with a total thickness of 0.5 mm was constructed.

The toner guide plate formed as described above is durable and has good toner guide performance.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view of a conventional toner cleaning device for a dry type electronic copying machine, and FIGS. 2 and 3 are sectional views of a toner guide plate according to the present invention. DESCRIPTION OF SYMBOLS 1... Rotating drum, 2... Blade, 3... Toner collection container, 4... Toner guide plate, 5... Support body, 6... Member with lower elastic modulus than thermoplastic urethane, 7... Thermoplastic urethane sheet.

Claims (1)

[Claims for Utility Model Registration] (1) The contact surface with the photoreceptor drum is a sheet of thermoplastic polyurethane with a thickness of 0. 05 to 0.5mm
range, hardness is JIS A scale 70° to 99°
polyester resin, polyimide resin, which has a lower elastic modulus than the thermoplastic polyurethane.
A toner guide plate for a dry type electronic copying machine, characterized in that a member made of a resin selected from polycarbonate resin and fluorine resin is superimposed on the thermoplastic polyurethane. (2) The thermoplastic polyurethane and the low elastic modulus sheet are laminated using adhesive tape or thermal adhesive tape, and the thickness of the laminated layer is
The toner guide plate for a dry-type male copying machine according to claim 1, which has a toner guide plate having a thickness in the range of 0.1 to 2 mm. (3) The dry type electronic copying machine according to claim 1, wherein the overlapping structure of the thermoplastic polyurethane and the low elasticity sheet has the same width, or only the thermoplastic polyurethane has a longer width. toner information board.