JPH0548200Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a developing device using a two-component developer.

(Prior Art) Conventionally, in a developing device using a two-component developer, a toner replenishment roller is disposed at the outlet of a toner hopper, and a means for replenishing toner on the developing roller side is adopted. A slitter is brought into contact with the supply roller, and toner is supplied to the developing roller side through a slit provided in the slitter.

As shown in FIG. 3, the slitter 12 is made of a material with elasticity and has a horizontally long shape, and is always in contact with the toner supply roller 1 while maintaining a constant pressure contact. 12 each slit 1
It is necessary to supply a certain amount of toner from 2a to the developer storage section 10 on the developing roller 4 side, but due to warping or bending due to the rotation of the toner replenishing roller 1,
The slitter 22 is deformed, and as a result, the state of contact with the replenishment roller is different between the center of the slitter and both sides thereof, and the amount of toner replenishment at the center of the slitter 12 is smaller than at both sides. This has the disadvantage of causing uneven supply of toner. This uneven supply of toner occurs not only when the toner supply roller is warped or bent, but also when the toner hopper is deformed by heat or force.

(Purpose of the invention) The present invention provides a toner replenishing device for a two-component developing device, which aims to eliminate the uneven toner replenishment that occurs between the toner replenishing roller and the slitter.

(Structure of the invention) In order to achieve the above object, the present invention includes a replenishment roller for replenishing the toner contained in the toner hopper to the developing roller side, and a slitter for scraping off the toner carried by the replenishment roller. The toner replenishing device is characterized in that the slitter is provided with an appropriate number of vertical notches, and the slitter is brought into contact with the replenishing roller without any gaps.

The present invention will be explained based on examples. Figure 1 shows
The toner contained in a toner hopper 3 is rotated by an agitator 8 and sent to a toner supply roller 1 disposed on the left side of the toner hopper 3.

The toner supply roller 1 has an uneven surface.
It is driven clockwise in the direction of the arrow, and comes into contact with a plate-like member 9 made of foamed polyurethane attached to one end of the toner hopper 3 to remove excess toner.
Excess toner and removed toner supply roller 1
has one end attached to the end of the toner hopper 3,
The other end comes into contact with a slitter 2 arranged to abut the toner supply roller 1, and a horizontally long slit 2a of the slitter 2 supplies a certain amount of toner to the developing roller side.

The slitter 2 is made of a material with elasticity, for example, a highly elastic plate such as a phosphor bronze plate, and the slit 2a on the lower end side is always pressed against the toner replenishing roller 1 with a constant pressing force. are in contact with each other. The slitter 2 is bent into a dogleg shape, and the slitter 2 that comes into contact with the toner replenishment roller 1 has an oblong shape that can scrape off the toner carried by the recesses on the uneven surface of the toner replenishment roller 1. A plurality of slits 2a are provided, and cut portions 2b are formed from the lower end of the slit 2 on the contact surface with the toner supply roller at appropriate intervals (FIG. 2A).

By providing such a notch 2b, the slitter 2 can minimize the deformation of the slitter 2 caused by the bending of the toner replenishing roller 1, and the entire length of the toner replenishing roller 1 and the slitter 2 can be suppressed. A uniform contact state can be obtained, and therefore, the toner supply state to the developer storage section 10 can be made uniform.

The toner in the toner hopper 3 is fed by the toner replenishing roller 1 and the slitter 2 into a developer storage section 10 provided with a developing roller 4, and is agitated and mixed with the carrier by the stirring roller 7 and the stirring roller 5, respectively, and is developed. The developing roller 4 can supply a uniform amount of toner to a photoreceptor drum (not shown) in the axial direction thereof.

In the present invention, by providing the notch 2b, the slitter 2 can be less affected by the bending of the toner replenishing roller 1, as well as the deformation of the toner hopper 3, and the slitter 2 can be moved with respect to the toner replenishing roller 1. Can be brought into uniform contact.

In the present invention, a phosphor bronze plate is used as the material for the slitter, but it is not limited to this, and other materials with strong elasticity can be used. Therefore, it is possible to appropriately select a shape and size that can scrape off a certain amount of toner from the surface of the toner supply roller. Furthermore, in addition to forming the cross-sectional shape of the surface of the toner replenishing roller in an uneven manner, it is also possible to adopt a shape that can hold a certain amount of toner and scrape it off with a slit of a slitter.

(Effects of the invention) In the conventional system, the state of contact between the slitter and the toner replenishment roller was different between the center and both sides due to warpage and flexure of the toner replenishment roller, resulting in uneven toner replenishment. By providing an appropriate number of notches in the sliver, it is possible to obtain an even contact state between the central part and its both sides, and it is possible to uniformly replenish toner to the developing roller side in the length direction of the replenishing roller. have an effect.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a two-component developing device according to the present invention, FIG. , b are a front view and a side view of a conventional sliver. 1...Toner supply roller, 2...Sliver, 2
a: slit, 2b: notch, 3: toner hopper, 4: developing roller, 5, 7: stirring roller.

Claims (1)

[Scope of utility model registration request] In a toner replenishment device equipped with a replenishment roller for replenishing the toner contained in a toner hopper to the developing roller side and a slitter for scraping off the toner carried by the replenishment roller, an appropriate number of vertical cuts are provided in the slitter. A toner replenishing device for a two-component developing device, characterized in that a slitter is brought into contact with a replenishing roller without any gap.