JPH0322992B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the structure of a developing section of an electronic copying apparatus.

Electronic copying devices usually perform copying by providing a charging section, an exposure section, a developing section, and a transfer section around a rotating photoconductor drum. To develop the image, many use a magnetic brush roll that supplies toner to the photoreceptor drum. However, when toner is supplied to the photoreceptor drum by this magnetic brush roll, a portion of the supplied toner becomes a toner cloud and flies upward due to impact with the photoreceptor drum. The toner that flies upward in this way is
It adheres to the ceiling of the housing of the developing section and gradually accumulates, and at a certain point it falls in the form of a lump onto the magnetic brush roll, which is then supplied as it is to the photoreceptor drum and adheres to it, resulting in toner stains and copy defects. There was a risk that this would occur.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to prevent copying defects such as toner stains caused by the above-mentioned toner cloud from occurring in the developing section of an electronic copying apparatus.

The developing section structure of the electronic copying apparatus according to the present invention is characterized in that a vibration device for slightly vibrating the ceiling is disposed on the ceiling of the developing section housing.

In the present invention, the vibrating device prevents the toner flying upward from between the photosensitive drum and the magnetic brush roll from adhering to the ceiling of the developing unit housing, so that the above-mentioned toner stains, etc. Copy defects can be prevented.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a developing section of an electronic copying apparatus according to a preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing the structure of a developing section of an electronic copying apparatus according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 indicates a photoreceptor drum, which is supported to rotate in the direction of arrow A. As shown in FIG. A developing section is provided adjacent to a portion of the photosensitive drum 1. The developing section 2 has a developing housing 3, and within the developing housing 3, a magnetic brush roll 4 is supported adjacent to the photosensitive drum 1 so as to rotate in the direction of arrow B. A fixed magnet (not shown) is disposed inside the magnetic brush roll 4 as is well known, and the fixed magnet forms a magnetic field for attracting the developer to the roll surface. A paddle 5 is provided diagonally below the magnetic brush roll 4, and this paddle 5 rotates in the direction of arrow C to remove the developer accumulated at the bottom of the developer housing 3 onto the surface of the magnetic brush roll 4. It has a lifting effect. The above developer consists of toner and a carrier, and the toner adheres to the carrier due to frictional electrification. Toner is supplied alone to the developing section, and in order to form a developer having such a structure, a blender 6 is provided for mixing the supplied toner and carrier.

The developer with the toner attached to the carrier is attracted onto the surface of the magnetic brush roll 4 by the magnetic field, and is moved toward the photosensitive drum 1 as the roll 4 rotates. . At this time, the height of the developer is adjusted to an appropriate height by the trimmer 7. A so-called magnetic brush is formed on the surface of the magnetic brush roll 4, and the tip of this magnetic brush comes into contact with the surface of the photoreceptor drum, and the toner is applied to the latent image by the electric force of the latent image formed on the surface of the photoreceptor. It is attracted and developed.

However, due to the impact when the tip of this magnetic brush contacts the surface of the photoreceptor drum,
The toner comes off the carrier and flies upward as shown by arrow T, resulting in development as a toner cloud. Therefore, in the present invention, in order to prevent this flying toner T from adhering to and accumulating on the ceiling 3a of the housing 3, a vibrating device 8 is disposed on the ceiling 3a, and the vibrating device 8 moves the toner toward the ceiling 3a. 3a
I'm trying to make it vibrate slightly. This vibration device 8
is preferably an ultrasonic vibrator; for example, an electrostrictive vibrator is used.

The vibration of the ceiling 3a caused by the vibration device 8 needs to be such that it does not affect the developing operation. Preferably, as shown in Figure B, the ceiling 3a is separate from the main body 3b of the housing 3, and the ceiling 3a is supported by elastic members 9, 10 such as springs, so that the vibrations of the ceiling 3a are transferred to the housing main body 3b.
It is best to prevent it from being transmitted to others.

[Brief explanation of drawings]

The figure is a schematic diagram showing the structure of a developing section of an electronic copying apparatus according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Photosensitive drum, 2... Developing section, 3... Developing section housing, 3a... Ceiling, 4... Magnetic brush roll, 8... Vibrating device.

Claims (1)

[Claims] 1. In order to prevent the toner flying upward from between the photoreceptor drum and the magnetic brush roll that supplies toner to the photoreceptor drum from adhering to the ceiling of the developing unit housing, a slight surface is placed on the ceiling. 1. A developing section structure of an electronic copying apparatus, characterized in that a vibrating device for vibrating is provided.