JPH0112272Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a structure for arranging developer spikes on a developing roller of an electrophotographic recording device.

Electrophotographic recording devices have recently made remarkable progress and are now being used not only in office copying machines but also in electronic computing devices and data transmission devices.

In these various applications, higher speed is required.

Conventionally, the developing mechanism of an electrophotographic recording device replenishes the amount of toner consumed during development from a toner supply mechanism to a roller to which a magnetic force is applied (hereinafter referred to as a magnet roller), and aligns the spikes of developer with a spike plate for development. was repeated.

However, when using a single magnetic roller, uneven development is likely to occur, and in order to eliminate uneven development, some systems have a first and second magnet roller installed in parallel. , when the developer is transferred between the first and second magnet rollers, the height and condition of the spikes may be disturbed. However, there is a need for an improvement in this problem, since the cutting plate causes the developer to stagnate and the developer gets stuck between the cutting plate and the magnet roller.

The purpose of this invention is to propose an improved mechanism that meets the above-mentioned requirements.The purpose of this invention is to perform dry development by bringing the spike-shaped developer formed on the surface of two parallel rollers into contact with the latent image forming body. In the developing device,
An adjusting roller made of a non-magnetic material is provided between the two rollers and on the side of the latent image forming body, and the adjusting roller is rotated by contacting with the spikes of developer of the two rollers. This can be achieved by a developing device characterized in that the spike-like developer is arranged on the surface of an adjuster roller.

That is, the adjuster roller of the present invention has the following features:
The roller adjusts the ears of the second stage while being rotated by coming into contact with the ears of the developer of the second stage roller.
The developer is not clogged between the rollers of the second stage or between the adjusting roller 5 and the first roller, and the developer can be transferred smoothly.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram of an embodiment of the present invention,
An electrostatic latent image formed in a portion (not shown) on the surface of the photosensitive drum 1 whose surface is a latent image forming body is transferred to a dry developer (toner) 7 by rollers (developing magnet rollers) 2 and 3 in a developing section 6. The image is developed by a dry developer that is magnetically attached in the form of a spike and is attracted to an electrostatic charge, and then transferred and printed onto a desired sheet of paper in a printing section (not shown).

In the figure, developer 7, which is replenished with dry developer from a dry developer replenishing section (not shown) and maintains a substantially constant amount, is brought into contact with the lower surface of a roller (developing magnet roller) 2 by a developer feed mechanism 8. The ears are attached to the surface in the form of ears, and the height of the ears is kept constant using the ear cutting plate 4, and the ears are brought into contact with the photosensitive drum.

In the figure, roller 2 is connected to roller 3 with developer 7.
The roller 3 performs the development first, and the roller 2 compensates for the insufficient development, thereby obtaining a high quality print through multiple development.

When the developer 7 is supplied from the roller 2 to the roller 3, if an adjuster roller 5 made of a non-magnetic material is provided between the two, the adjuster roller adjusts the ears on the roller 3 while being rotated by the contact of the ears. , the development by the roller 3 can be done uniformly, and it is also possible to prevent the dry developer from staying between the rollers 2 and 3.

FIG. 2 shows the condition in which the ears on the roller 3 are adjusted by the adjuster roller 5, and in contrast, FIG. 3 shows the condition of the ear on the roller 3 without the adjuster roller 5.

In this example, an example of reverse direction development in which the rotation directions of the photosensitive drum 1 and the rollers 2 and 3 are different is shown, but the effect of the adjuster roller 5 is the same in forward direction development.

Further, although an example is shown in which the developing magnet roller has two stages, the effects of the present invention are still effective even if the developing magnet roller is provided in multiple stages as required.

As described above, the dry developing mechanism of an electrophotographic recording device according to the present invention does not cause accumulation of developer or disturbance of the height or condition of the ears when the developer is transferred between multiple magnet rollers. , high-quality development can be achieved even during high-speed processing with a simple additional mechanism, which is highly effective.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the present invention, FIG. 2 is an explanatory diagram of the adjuster roller effect, and FIG.
The figure shows the shape of the ear without an adjuster roller. In the figure, 1 is a photosensitive drum, 2 and 3 are rollers, 4 is a cutting plate, 5 is an adjuster roller, 6 is a developing section, 7 is a developer, and 8 is a developer feeding mechanism.

Claims (1)

[Claims for Utility Model Registration] In a developing device that performs dry development by bringing developer spikes formed on the surface of two rollers arranged in parallel into contact with a latent image forming member, an intermediate portion between the two rollers. Further, an adjusting roller made of a non-magnetic material is provided on the side of the latent image forming body, and the adjusting roller is rotated by being brought into contact with ears of the developer of the two rollers, and the spike-shaped developer is formed on the surface of the adjusting roller. A developing device characterized by adjusting the .