JPH0226227B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a developing device for an electronic copying machine using a one-component non-magnetic developer.

Prior Art Conventionally, cascade development and magnetic brush development have been widely used as development methods for electronic copying machines, but since both use two-component developers,
There are following problems. In other words, when using a two-component developer for a long period of time, the surface of the carrier becomes contaminated with the toner composition and the chargeability of the carrier is impaired, so an expensive control mechanism is provided to control the mixing of the carrier and toner. In addition to the need to change the ratio, the carrier damages the photoreceptor, requiring periodic replacement of the developer, making maintenance cumbersome. Recently, a development method using a one-component magnetic developer using a toner containing magnetic powder with relatively low resistance has been proposed as a way to improve these problems, but this method causes high-temperature dark transfer defects and other problems. , it has disadvantages such as not being able to produce clear color copies.

In order to improve these drawbacks, a developing method using a developer using a non-magnetic toner having high resistance has also been proposed. This developing method is carried out as follows using, for example, the developing apparatus shown in FIG. 1 of the accompanying drawings. That is, a developing roll 3 is provided in a hopper 2 disposed near the photoreceptor 1 in close proximity to the photoreceptor 1, and a developing bias is applied to the developing roll 3 by a power source 4. Also,
A one-component developer 5 made of non-magnetic toner is stored in the hopper 2, and is carried to the photoreceptor 1 side as the developing roll 3 rotates, and an electrostatic latent image 6 formed on the surface of the photoreceptor 1 is formed on the surface of the photoreceptor 1. It is starting to be developed. In this process, it is important to form a thin toner layer with a uniform thickness on the developing roll 3, and for this purpose, the thickness of the developer adhering to the surface of the developing roll 3 is regulated to be uniform. A toner layer regulating blade 7 is used as a regulating member.
Moreover, instead of such a regulating blade 7, a regulating roll in the form of a roll has been proposed. However, in the case of this regulating roller, since the developing roll and the regulating roll are rotated so that their opposing surface portions move in opposite directions, a large driving torque is required, and the housing of the developing device, It is necessary to make the bearings etc.
Furthermore, since the drive motor also requires a large output, there are disadvantages in that the device becomes larger and the cost increases.

OBJECTS OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art as described above, reduce the required driving torque in a developing device using a one-component non-magnetic developer, and create a compact, lightweight, and low-cost device. The goal is to

Structure of the Invention According to the present invention, in a one-component nonmagnetic developing device including a developing roll and a regulating member that regulates the thickness of the developer adhering to the surface of the developing roll, the regulating member is in a roll shape, It is composed of an internal elastic body and a metal thin film on the surface, and is brought into pressure contact with the developing roll, thereby lowering the friction coefficient of the regulating member.
Reduces drive torque, making the entire device smaller, lighter, and
It can be made low cost.

Embodiments Next, the present invention will be described in more detail with regard to embodiments of the present invention based on FIG. 2 of the accompanying drawings.

FIG. 2 schematically shows the configuration of a developing device of an electronic copying machine as an embodiment of the present invention. Second
As shown in the figure, this developing device performs development using a one-component nonmagnetic developer, and a developing device main body 12 is installed near a photoreceptor 11. The main body 12 has a hopper 13 having an opening 13A on the side of the photoreceptor 11.
A one-component non-magnetic developer 14 is housed inside the hopper 13, and a portion of the lower part of the hopper 13 has an opening 1.
Developing roll 15 protruding from 3A toward the photoreceptor 11 side
is accommodated. The developing roll 15 has no irregularities on its surface, is rotated in the direction of the arrow by a drive system (not shown), and is applied with a developing bias by a bias power source 16. Further, a roll-shaped regulating member 17 is rotatably provided above the developing roll 15 while being in pressure contact with the developing roll 15 . The regulating member 17 consists of a roll-shaped metal core 17A and an elastic layer 17B provided around the metal core 17A, and a metal plating layer 17C as a thin metal film is applied around the elastic layer 17B. .

The metal plating layer 17C is formed by forming a copper layer with a thickness of about 1 to 10 μm by electroless plating, and then forming a chromium layer with a thickness of about 5 to 50 μm by electroplating to give surface strength. It is something.

The regulating member 17 rotates in the direction of the arrow and regulates the developer attached to the surface of the developing roll 15 so that it has a uniform thickness due to the pressure contact force of the regulating member 17 and the relative speed difference. The developer regulated to a constant thickness by the regulating member 17 is transferred to the photoreceptor 11.
The electrostatic latent image 19 formed on the surface of the photoreceptor 11 is developed.

Effects of the Invention Comparing the case where the surface of the elastic layer is as it is as in the conventional regulating member and the case where the metal plating layer 17C is applied to the surface of the elastic layer of the regulating member as in the present invention described above, it is found that the friction in the conventional case is The coefficient of friction was 0.5 to 0.8 or more, whereas the coefficient of friction in the case of the present invention was 0.1 to 0.8.
0.3, according to the present invention, the required driving torque can be reduced to 1/2 to 1/10 or less compared to the conventional case, and the housing, bearings, etc. can be simplified accordingly, and it is lightweight and It has become possible to downsize and reduce costs.

[Brief explanation of drawings]

FIG. 1 of the accompanying drawings is a schematic diagram for explaining an example of a conventional developing device, and FIG. 2 is a schematic diagram showing the configuration of a developing device as an embodiment of the present invention. DESCRIPTION OF SYMBOLS 11... Photoreceptor, 12... Developing device main body, 13... Hopper, 13A... Opening part, 14... 1-component non-magnetic developer, 15... Developing roll, 16... Bias power supply,
17... Regulating member, 17A... Metal core, 17B... Elastic layer, 17C... Metal plating layer, 19... Electrostatic latent image.

Claims (1)

[Claims] 1. In a one-component non-magnetic developing device equipped with a developing roll and a regulating member that regulates the thickness of the developer adhering to the surface of the developing roll, the regulating member is roll-shaped and has an inner elastic body and a surface of the regulating member. 1. An electrostatic latent image developing device comprising a metal thin film and being pressed against the developing roll.