JPS59182479A - Toner cloud preventive device in electrophotographic copying machine or the like - Google Patents

Abstract

PURPOSE:To suck completely a toner cloud, and to prevent its scattering in the direction of a photosensitive drum by placing a partition in a suitable place in a suction port of a suction part of the lower part of a developing machine, and directing its direction in one circumference direction of a magnetic roll of the upper part. CONSTITUTION:A suction part 12 connected to an air filter is provided on the lower part of a developing machine 6, and a suction port 13 is pierced and placed toward one circumference of the lower surface of a magnetic roll 10 provided in the vicinity of the circumference of a photosensitive drum 5. As for the suction port 13, plural partitions 14 are placed in suitable places so that a suction force becomes uniform extending over the whole surface in the suction port 13. A toner which is electrostatically and frictionally charged by a blender 7 and mixed with a carrier moves to a paddle wheel 8, a mixing plate 9 and the roll 10, and develops the drum 5. A toner cloud generated at the time of said carrying is sucked successively by the suction port 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toner cloud prevention device in an electrophotographic copying machine or the like.

In a conventional device of this kind, as shown in FIG. The problem occurred within 2 days of the developing machine, as it was installed with holes pointing toward the camera.
The toner cloud that is trying to scatter outside the developing machine 2 cannot be completely absorbed, and some of it scatters onto the surface of the photoreceptor drum 10 and is deposited on the output copy, causing the background of the copy. However, since the suction port 4 of the suction section 3 is configured as shown in FIG. 2, the suction force of the air is uneven. There is a tendency to concentrate in areas with strong suction force, so when a large amount of toner cloud is generated, the toner cloud is concentrated at both ends of the suction port 40 where suction force is strong, and this eliminates the background at both ends of the copy. It had the disadvantage of being extremely dirty.

The present invention has been made in order to eliminate the drawbacks of the conventional toner cloud prevention device, in which the suction port of the suction section provided at the lower part of the developing machine is directed toward one periphery of the mag roll in the upper developing machine. By placing
By making it possible to suck all the toner cloud generated around the mag roll into the suction section, and by providing a partition inside the suction port, the toner cloud to be sucked into the suction port can be sucked over the entire surface of the suction port. An object of the present invention is to provide a toner cloud prevention device for an electrophotographic copying machine, etc., which is capable of evenly suctioning toner.

The present invention will be described in detail based on the embodiments shown in the drawings.

FIG. 3 is a schematic diagram showing an embodiment of the toner cloud prevention device of the present invention.

A developing device 6 is arranged around one area of the photoreceptor 5. The developing machine, 6
, from the blender 7 disposed in the image storage therein, to the periphery of the photoreceptor drum 5, forming a chip-like mound conveying path for the agent, to a paddle wheel 8, a cross mixing belt 9, a mag roll 10, Trimmer grates 11 and the like are arranged at appropriate positions. A suction portion 12 connected to an air filter (not shown) is provided at the bottom of the developing device 6-, and a suction port 13 of the suction portion 12 is provided near one periphery of the photoreceptor drum 5. Magroll 1 in image machine 6
0 toward one periphery of the lower surface of the suction port 1.
As shown in Figure 4, 3 is partitioned at a suitable place inside the 1)
Place 4.

The present invention is constructed as described above.

Next, its operation will be explained.

The toner is fed in appropriate amounts from a toner container (not shown) via a toner dispenser into a reservoir in the developing device 6, where it is triboelectrically charged by a blender 7 and mixed with carrier. The toner mixed with this carrier is passed from the paddle wheel 8 to the cross mixing single.
The toner content is made uniform in the axial direction by the toner 9, and the toner is picked up by the mag roll 10. The Magroll 10
The toner picked up on the soil is removed from the trimmer plate 11.
The developer is conveyed to the electrostatic latent image on the photoreceptor drum 5 with an appropriate amount of developer being controlled. In this process, a toner cloud is generated in the developing device 6 when the toner is stirred and conveyed by the blender to 7, the paddle wheel 8, the mag roll 10, and the like. Then, the toner cloud is transferred to the suction port 1 of the suction section 12 provided at the lower part of the developing device 6.
Since the suction port 13 is oriented toward one periphery of the lower surface of the mag roll 10 as described above, the toner cloud is sucked out from the periphery of the mag roll 10. All the air is sucked into the suction section 12 through the suction port 13 and then sucked into the air filter under negative pressure. When this toner cloud is sucked from the suction port 13 into the suction unit 12, a partition 14 is placed at an appropriate position inside the suction port 13. Since the toner cloud is configured to be uniform over the entire surface, the toner cloud is sucked uniformly over the entire surface by the suction port 13 without being concentrated at both ends thereof.

The present invention is configured and operates as above,
Conventionally, the suction port of the suction unit was arranged toward one periphery of the photoreceptor drum, so that the entire generated toner cloud could not be suctioned and a portion of it was deposited on the surface of the photoreceptor drum. This has the effect of completely preventing the toner cloud from scattering, and when the toner cloud is sucked into the suction section 12, the suction port 13 itself has a partition 14 at an appropriate place within the suction section 12. By distributing several parts, the suction force of the air from the part is made uniform over the entire surface of the suction port 13, so the toner cloud is concentrated on both ends of the suction port 10130. Therefore, it is possible to almost completely prevent the background from being badly stained at both ends of the copy, which conventionally occurs due to this concentrated suction, and has the effect that high-quality copies can always be provided.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a conventional developing machine, Fig. 2 is a sectional view of the suction port of the suction section, Fig. 3 is a schematic diagram of the developing machine of the present invention, and Fig. 4 is the same, a sectional view of the suction port. FIG. In the figure, 5...photosensitive drum, 6...developing machine, 10
...Magroll, 12Il...Suction part, 1
3e... Suction port, 14... Partition 9°

Claims (1)

[Claims] The direction of the suction port of the suction part provided at the lower part of the developing machine arranged around one side of the photoreceptor is oriented toward the lower part of the mag roll in the shaped machine located above the developing machine, and
Furthermore, an electric current is characterized in that an appropriate number of partitions are arranged at appropriate positions inside the suction port so that the toner cloud can be uniformly sucked over the entire surface of the suction port.
F Toner cloud prevention device in photocopiers, etc.