JPH0453982A - Developing device - Google Patents

Abstract

PURPOSE:To reduce torque applied to an agitator when toner is filled up and to prevent the locking of the agitator by installing an elastic member having plural toner passing windows on an attaching side at a part of or over the entire length of the rotating arm of the agitator. CONSTITUTION:The elastic member 10 having the plural toner passing windows 10A is attached at a part of or over the entire length of the rotating arm 4A of the agitator 4. The member 10 is formed of a substance having proper elasticity such as a film, rubber, a flat spring material. Therefore, when a toner cartridge 1 is full of the toner, the tip of the member 10 is bent by the resistance of the toner when the agitator 4 is rotated in a direction shown by an arrow. The toner smoothly moves by the windows 10A provided on the member 10, and the torque to the agitator in the state where the toner is filled up is reduced. Thus, the locking of the agitator in the state where the toner is filled up is prevented and the toner is smoothly carried even when the quantity of toner is small.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a developing device in an image forming apparatus such as a laser printer.

(Prior Art) FIG. 3 shows a side view of the configuration of a unitized developing device.
The toner cartridge 1 and the developing section frame 2 are connected at an adhesive section 3.
They are bonded together by heat welding or heat caulking. An agitator 4 located in the center of the toner cartridge replenishes the toner T in the cartridge to a toner replenishing roller 5 in the developing section.

Since the toner supply roller rotates while being in frictional contact with the developing roller 6, frictional charging occurs between the developing roller and the toner, and the toner adheres to the developing roller. The toner adhering to the developing roller is scraped off by the blade 7, and a thin layer of toner is formed on the surface of the developing roller. Then, at the contact portion between the illustrated belt-shaped photoreceptor 8 and the developing roller, toner adheres to the exposed portion of the photoreceptor, making the latent image visible. Note that a waste toner storage section 9 is provided below the toner cartridge 1.

(Problems to be Solved by the Invention) Incidentally, many conventional developing devices have a mechanical life span that is equivalent to that of a conventional developing device, and most of them are of the type in which toner is supplied from the outside using a toner cartridge.

Therefore, the toner capacity in the developing device does not need to be very large, and the torque applied to the agitator is also small.

However, in recent years, with the development of low-cost, compact laser printers, the development device itself has been considered a supply, and as shown in Figure 3 above, a toner cartridge and development section have been constructed as one unit, and a disposable type has been created. Ta.

Therefore, if the developing device is configured as shown in Figure 3, a certain amount of disposable toner must be put into the developing device, which naturally increases the load placed on the agitator, and in the conventional agitator, a lock condition occurs. There were some problems that occurred.

The object of the present invention is to eliminate this problem and reduce the torque applied to the agitator even when the toner is full, thereby preventing the lock state from occurring.

(Means for Solving Problem 111) In order to solve the above problems and achieve the object, the present invention supplies toner to a toner replenishment roller by rotating an agitator in a toner cartridge, and comes into rotational contact with the toner replenishment roller. In a developing device having a developing roller, a blade, etc. that scrapes off toner attached to the developing roller to form a thin layer, an elastic member having a plurality of toner through holes on the mounting side is provided over a part or the entire length of the rotating arm of the agitator. It is characterized by being attached.

(Function) According to the present invention, when there is a large amount of toner in the toner cartridge, the tip of the elastic member attached to the agitator bends, and a plurality of toner through-holes formed on the mounting side of the elastic member allow the toner to be removed. can move smoothly, and the torque of the agitator can be reduced even when the toner is full.

(Embodiment) FIG. 1 shows a perspective view of an embodiment of the present invention, in which a rotating arm 4A of an agitator 4 is provided with an elastic member 10 having a plurality of toner passage windows 10A over a part or the entire length (this is not shown in the drawings). (indicates the condition).

The elastic member 10 is made of a material having appropriate elasticity, such as a film, rubber, or a thin plate spring material.

Further, the toner pass-through window 10A may have a rectangular shape as shown in FIG. 1, a round shape, a trapezoidal shape, etc., depending on the toner material (viscosity, particle diameter, etc.), the rotational speed of the agitator, torque, etc.

FIG. 2 shows an operating state diagram of the elastic member 10 attached to the rotating arm 4A of the agitator 4, and FIG. 2 (1) shows a state in which the toner cartridge 1 contains a large amount of toner. At this time, when the agitator 4 rotates in the direction of the arrow, the tip of the elastic member 10 is bent due to the toner resistance, as shown in the figure, and the window 10 provided in the elastic member 10 is bent.
A allows the toner to move smoothly and reduces the torque of the agitator when the toner is full.

Further, (2) in the same figure shows a state in which toner is running low, and at that time the tip of the elastic member stands up, allowing toner to be supplied to the developing roller.

(Effects of the Invention) As explained above, the present invention provides a method for locking the agitator when the toner is full by a simple means when the toner cartridge and the developing section are integrated into a unit and are handled as replacement parts. It is possible to prevent this and to smoothly transport toner even when there is a small amount of toner.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a diagram showing the operating state of an agitator, and FIG. 3 is a side view of a unitized developing device. l...Toner cartridge, 2...Developing section 7L
/-mu, 3...adhesive part, 4...agitator,
4A...Rotating arm, butt...Toner supply roller, 6...Developing roller, 7...Blade,
8... Photoreceptor, 9... Waste toner storage section, 10.
...Elastic member, IOA...window.

Claims (1)

[Scope of Claims] A developing roller that supplies toner to a toner replenishing roller by rotation of an agitator in a toner cartridge, that comes into rotational contact with the toner replenishing roller, and a blade that scrapes off the toner adhering to the developing roller into a thin layer. What is claimed is: 1. A developing device comprising: an elastic member having a plurality of toner through holes on a mounting side extending over part or the entire length of the rotary arm of the agitator.