JPS61116373A - Developer feeder - Google Patents

Abstract

PURPOSE:To suppress the generation of a cavity due to the aggregation of a developer and to feed the developer stably and precisely by reciprocating an agitating plate between one inwall side of a casing and the center side. CONSTITUTION:The casing for storing toner 11 to be fed is arranged on the upper part of a developing device 10 and a feed roller 13 is pivoted on an opening part 12A on the lower end of the casing 12 so as to close the opening part 12A. When the feed roller 13 is rotated, toner 11 is dropped and supplied through a gap between the casing 12 and the roller 13. On the upper position of the feed roller 13, the agitating plate 14 to be displaced between one inwall side of the casing 12 and the center is pivoted at its intermediate part so as to be vibrated and displaced.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a developer housed in a casing that is supplied by cooperation with gravity, and for example, a two-component developer consisting of a mixture of toner and carrier. The present invention relates to an improvement in a developer supply device for replenishing toner to a developing device using a system developer.

[Technical background of the invention and its problems] A developing device that uses a two-component developer is usually equipped with an automatic toner detection device for detecting toner concentration, and the toner concentration in the developing device is determined by a specified value. When it is detected that the level has fallen below the level, the developer supply device replenishes toner.

In the conventional developer supply device, as shown in FIG. 2A
Toner is replenished by rotation of a feed roller 4 arranged so as to close the toner.

By the way, a large amount of toner is always stored inside the casing 2, and the toner is subject to pressure and temperature due to its own weight.

It tends to aggregate due to humidity. When replenishing the toner 3 in a particularly hot and humid condition, the agglomeration phenomenon gradually progresses from the wall side to the center side, and after a while, as shown in FIG. A cavity 5 is formed in the toner 3, which prevents the toner 3 from coming into contact with the feed roller 4, making it impossible to replenish toner.

Conventionally, in order to prevent the formation of cavities, a stirring plate 6 is mounted above the feed roller 4 as shown in FIG. 6(A).
is installed, but if agglomeration occurs above this stirring plate 6, a cavity 5 will be formed below it as shown in FIG. 6(B).
Similarly to the above, it becomes difficult to replenish toner.

Further, as shown in FIG. 7 (A>), a hammer 7 is provided on the side of the casing 2, and the hammer 7 is used intermittently to
A structure has also been proposed in which a shock is applied by striking the toner, but in this case, as shown in Figure 7 (B), the mechanical vibration causes adjacent toner particles to become close together, and conversely promotes the formation of cavities. result.

[Object of the Invention] The present invention has been made in view of the above circumstances, and can prevent the formation of cavities caused by agglomeration of the developer, and can provide a stable and stable developer.
Another object of the present invention is to provide a developer supply device that can reliably supply developer.

[Summary of the Invention] In order to achieve the above object, the present invention provides a developer supply device that supplies developer contained in a casing in cooperation with gravity. The structure includes a stirring body that is displaced between the two sides, and a drive means that reciprocates the stirring body, and the stirring body is reciprocated between the inner wall side and the center side of the casing, and most of the inside of the casing is By pressing the developer from one direction, it is possible to prevent the developer from coagulating and forming cavities.

[Embodiments of the invention] Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional front view showing a first embodiment of a developer supply device according to the present invention.

This developer supply device is a device that supplies toner 11 to a developing device 10 that uses a two-component developer.
A casing 12 containing replenishing toner 11 is disposed above the casing 0, and a feed roller 13 is pivotally supported at an opening 12A at the lower end of the casing 12 so as to close the opening 12A. The feed roller 13 is driven to rotate based on a toner concentration signal from a sensor (not shown) built into the developing device 10, and when it rotates, it drops and supplies the toner 11 through a gap with the casing 12. It has become.

The casing 1 is located above the feed roller 13.
A stirring plate 14 serving as a stirring body is displaceable between one inner wall surface side and the center side of the casing 12, and its intermediate portion is pivotally supported on the casing 12, so that the stirring plate 14 can be oscillatedly displaced.

The material of this stirring plate 14 is as follows:
The same material as 1, such as styrene.

It is desirable to use a material mixed with acrylic resin, and by doing so, frictional charging between the toner 11 and the stirring plate 14 can be reduced. Furthermore, if at least the surface is conductive, triboelectric charges can be grounded via the casing 12.

Above the pivot point 14A of this stirring plate 14 is a casing 1.
A drive par 15 is provided protruding toward the outer wall of 2.

A flexible rubber seal member 17 is attached to the through hole 16 on the casing 11 through which the drive par 15 passes,
It is designed to prevent toner from leaking through the through hole 16.

As a driving means for reciprocating the stirring plate 14, an eccentric cam 18 driven by a motor is arranged in contact with a pressure receiving plate 19 at the tip of the drive par 15. Although the pressure receiving plate 19 and the eccentric cam 18 do not constitute a positive cam mechanism, it goes without saying that the drive member 15 can be returned to its original position by the action of the repulsive force of the toner or gravity. In order to further ensure the return of the drive par 15, it is also possible to use a biasing member (not shown) to return the drive par 15 elastically.

Next, the operation of the above embodiment will be explained.

The developer supply device drives the eccentric cam 18 with a motor at predetermined intervals to move the stirring plate 14 in the direction of arrow A.

Since the toner 11 is oscillated in the A' direction, the toner 11 housed in the casing 12 is pushed over a wide range from one inner wall side of the casing 12 through the center to the opposite inner wall side. .

This pressing force is applied against the tendency of the toner 11 to agglomerate from the inner wall surface to the center of the casing 12.
Since the force presses the toner 11, it is possible to prevent the agglomeration of the toner 11 over a wide range within the casing 12, and even if the casing 1
Even if it partially aggregates near the inner wall surface of No. 2, it can be broken down quickly. As a result, it is possible to reliably prevent the formation of cavities, which has been a problem in the past, and it is possible to supply the toner 11 smoothly and stably.

FIG. 2 is a partial longitudinal sectional front view showing a second embodiment of the present invention, in which a rack 20 is cut into the drive par 15, and a pinion 21 meshing with the rack 20 is reversibly rotated to swing the stirring plate 14. It can also be configured as follows.

FIG. 3 is a partial longitudinal sectional front view showing a third embodiment of the present invention, in which the base end of the drive par 15 is pivotally supported on the stirring plate 14, and a crank 22 is attached to the tip end of the drive par 15.
Alternatively, the stirring plate 14, the drive par 15, and the crank 22 may constitute a swinging crank mechanism to swing the stirring plate 14.

FIG. 4 is a partial longitudinal sectional front view showing a fourth embodiment of the present invention, in which the drive par 15, the pressure receiving plate 18 and the eccentric cam 1 are shown.
It is also possible to provide two sets of stirring plates 9 and to positively swing the stirring plate 14.

It should be noted that the above embodiment is merely an example, and it goes without saying that various modifications can be made within the scope of the gist of the present invention. For example, the developer to be supplied is not limited to toner of a two-component developer. The one-component developer itself may be used, and it is also possible to apply the present invention to the developing device itself and provide an agitator inside the casing.

[Effects of the Invention] As is clear from the above detailed description, the developer supplying device of the present invention has two parts attached to the casing by reciprocating the stirring plate between one inner wall side and the center side of the casing. Since the agitated developer is pressed and stirred from one inner wall side of the casing to the opposite inner wall side via the center side, it is possible to prevent the formation of cavities due to agglomeration of the developer, and it is stable and , developer can be reliably supplied.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a first embodiment of the invention, FIG. 2 is a partial longitudinal sectional front view showing a second embodiment of the invention, and FIG. 3 is a partial longitudinal sectional view showing a third embodiment of the invention. A front view, FIG. 4 is a partial longitudinal sectional front view showing a fourth embodiment of the present invention, and FIG.
, (B), Figure 6 (A). 7(B), FIGS. 7(A) and 7(B) are sectional views showing a conventional developer supply device, respectively. 11... Developer, 12... Casing, 14... Stirring plate, 18... Eccentric cam, 19... Pressure receiving plate, 20 ...Rack, 21...Binion, 22...
crank. (A) -1-11no/CB) A

Claims (2)

[Claims] (1) In a developer supply device that supplies developer contained in a casing in cooperation with gravity, an agitator that is displaced between one inner wall side and the center side of the casing;
A developer supply device comprising: a drive means for reciprocating the stirring body. (2) The stirring body is a stirring plate whose intermediate portion is pivotally supported on the casing, and its rocking displacement presses most of the developer inside the casing from one side. Developer supply device.