JPH04104173A - One-component developing device - Google Patents

Abstract

PURPOSE:To make a motor for driving unnecessary by carrying out frictional rotation by bringing toner carriers and a photosensitive body into pressurized contact. CONSTITUTION:A toner carrier retaining member 2 is provided with a recessed shaped arc surface 2b in an axial direction of the photosensitive body 6, in the arc surface 2b, sphere shaped recessed parts 2c are provided lined up along the axial direction of the photosensitive body 6, and three rows of the sphere shaped recessed parts 2c are provided in the rotational direction of the photosensitive body 6. In each sphere shaped recessed part 2c, sphere shaped toner carriers 1 are rotably supported, and each sphere shaped toner carrier 1 is brought into a pressurized contact with the photosensitive body 1 surface. The toner carriers 1 are in a pressurized contact with the photosensitive body 6, and is rotated responding to the rotation of the photosensitive body 6. Thus, by allowing the sphere shaped toner carrier to frictionally rotate in pressurized contact with the photosensitive body, the motor for driving of the toner carrier becomes unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus such as a copying machine or a printer using an electrophotographic process, and particularly to a -component developing device.

[Conventional technology]

FIG. 3 shows a conventional one-component developing device.

As shown in the figure, the toner +05 is conveyed to the charging roller 103 by the stirring member 104, charged, and adheres to the roller-shaped toner carrier 101. The toner 105 attached to the toner carrier 101 is formed into a thin layer by the blade +02 as the toner carrier 101 rotates, and is attached to an electrostatic latent image on a photoreceptor (not shown), depending on the amount of printing. consumed.

The toner carrier 101 was being rotated by a motor or the like.

[Problem to be Solved by the Invention j] In the conventional single-component developing device described above, when printing an image with a high proportion of solid black, it is necessary to increase the rotation speed of the toner carrier 101; Since it is in pressure contact with the photoreceptor, the torque is large, requiring a high-torque motor, and the resulting noise is also large.

Furthermore, since the toner carrier 101 is rotated by a driving means such as a motor, it is difficult to downsize and reduce the cost of the apparatus body.

Furthermore, the toner carrier may be damaged when replacing the developing device, etc.
If clumps or the like were mixed in, a thin layer of appropriately charged toner would not be formed on the toner carrier 101, and when the developed toner was transferred to recording paper, the density would be low or white spots would appear.

SUMMARY OF THE INVENTION An object of the present invention is to provide a one-component developing device that eliminates the need for a motor, thereby reducing the size and cost of the device itself, and preventing a decrease in density.

[Means for Solving the Problems] In order to achieve the above object, a one-component developing device according to the present invention includes a toner carrier holding member, a plurality of spherical toner carriers, and toner. The toner carrier holding member holds a plurality of spherical toner carriers,
A plurality of spherical toner carriers are held so as to be able to roll in a plane facing the photoconductor, and a plurality of spherical toner carriers are in pressure contact with the photoconductor and rotated by friction as the photoconductor rotates. The agitating member introduces the toner into the gap between the toner carrier holding member and the spherical toner carrier, and as the spherical toner carrier rotates, the lever forms a thin layer within the gap and is charged by friction.

[Operation] The toner carrier is formed into a spherical shape, and the spherical toner carrier is frictionally rotated by pressure contact with the photoreceptor.

This eliminates the need for a motor for driving the toner carrier.

Furthermore, by arranging a plurality of spherical toner carriers in the same plane, even if toner is not properly formed on some toner carriers, other adjacent toner carriers can supplement the development. , avoid a decrease in density or white spots.

[Example] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram showing an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion of the same.

Generally, an image forming apparatus using an electrophotographic process includes a charger 7, an exposure source 8, a developer 11, a transfer charger 9, and a cleaner around a cylindrical photoreceptor 6, as shown in FIG. 5, the photoreceptor 6 is rotated, the surface of the photoreceptor 6 is first uniformly charged with a charger 7, and the charged surface is exposed to light with an exposure source 8 to form an electrostatic latent image. death,
Charged toner 3 is attached to the electrostatic latent image by a developing device 11 to make it visible, and then the developed image is transferred to the recording paper IO by a transfer charger 9 and fixed. On the other hand, the toner remaining on the surface of the photoreceptor 6 is scraped off by a cleaner 5 in preparation for the next process.

The developing device 11 according to the present invention includes a toner carrier holding member 2 , a spherical toner carrier 1 , a stirring member 4 , and toner 3 .

The toner carrier holding member 2 has a toner storage section 2a that stores the toner 3, and a stirring member is installed inside the toner storage section 2a. Furthermore, the toner carrier holding member 2 has a concave arcuate surface 2b along the axial direction of the photoreceptor 6.

The arc surface 2b includes spherical recesses 2c arranged along the axial direction of the photoreceptor 6, and three rows of spherical recesses 2C are provided along the rotational direction of the photoreceptor 6. In each spherical recess 2C,
A spherical toner carrier 1 is rotatably supported, and each spherical toner carrier 1 is pressed against the surface of the photoreceptor 1 .

Further, the spherical recess 2C communicates with the toner storage section 2a, and the toner 3 is guided by the stirring member 4 into the gap between the spherical recess 2c and the spherical toner carrier l, and is guided by the rotation of the photoreceptor 6. As the toner carrier 1 rotates accordingly, the toner layer becomes thinner and triboelectrically charged within the gap.

The individual toner carriers 1 have a spherical shape and are arranged at regular intervals to form three rows, but adjacent rows are arranged as shown in FIG. 3 to prevent undeveloped areas. , are placed offset. In the embodiment, there are three rows, but there may be three or fewer rows, or three or more rows, and the number of rows may be increased or decreased as necessary.

The toner carrier 1 is in pressure contact with the photoreceptor 6 and rotates as the photoreceptor 6 rotates.

The toner 3 is transferred to the toner carrier holding member 2 by the stirring member 4.
The toner 3 is guided into the gap between the toner carrier 1 and the toner carrier 1, and as the toner carrier 1 rotates in accordance with the rotation of the photoreceptor 6, the toner 3 becomes a thin layer within this gap and is triboelectrically charged. The charged toner 3 on the toner carrier 1 adheres to an electrostatic latent image on the photoreceptor 6 formed by the charger 7 and the exposure source 8, and development is performed.

[Effects of the Invention] As explained above, the one-component developing device of the present invention rotates the toner carrier by friction by pressing the toner carrier against the photoreceptor, so there is no need for a motor for driving, and the device body can be made smaller. transformation,
Lower costs and lower noise can be achieved.

Further, by increasing or decreasing the number of rows of toner carriers, it is possible to match the purpose of use of the apparatus.

Furthermore, even if toner is not properly formed on the toner carrier because the toner carrier is damaged or a clump is mixed in when replacing the developer, the toner carrier next to it or in the row next to it will still be able to develop. By supplementing, it is possible to avoid low density and white spots.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a partially enlarged view of a developing device seen from below a toner carrier, and FIG. 3 is a block diagram showing a conventional example. 1... Toner carrier 2... Toner carrier holding member 3... Toner 4... Stirring member 5... Cleaner 6... Photoreceptor 7... Charger
8... Exposure source 9... Transfer charger 10...
Recording paper 11...Developer patent applicant NEC Corporation

Claims (1)

[Claims] (1) A one-component developing device including a toner carrier holding member, a plurality of spherical toner carriers, and toner, wherein the toner carrier holding member includes a plurality of spherical toner carriers,
A plurality of spherical toner carriers are held so as to be able to roll in a plane facing the photoconductor, and a plurality of spherical toner carriers are in pressure contact with the photoconductor and rotated by friction as the photoconductor rotates. A component characterized in that it is introduced into a gap between a toner carrier holding member and a spherical toner carrier by a stirring member, becomes a thin layer within the gap by rotation of the spherical toner carrier, and is triboelectrically charged. Developing device.