JPH04122961A - Developing device - Google Patents

Abstract

PURPOSE:To loosen developer attached and to maintain developer stirring and carrying ability so that a good image can be obtained by giving vibration or shock to the developer by a vibration and shock member. CONSTITUTION:When the fluidity of the developer is lowered, the developer adheres to an ellipse board 2 and grows, when the worst comes to the worst, an aperture pat 6 is buried by the developer, so that it does not entirely contribute to the stirring and carrying of the developer. Therefore, a round bar 7 as the vibration and shock member for preventing the developer from adhering is movably provided on the aperture pat 6 of the ellipse board 2, then the round bar 7 moves about in the aperture part 6 by gravity accompanying by the rotation of the ellipse board 2 so that the developer is loosened by vibration and shock, and the good stirring and carrying ability can be always kept while the developer is prevented from adhering to the aperture part 6. And since the vibration and the shock go down inside the developer by its gravity, material having at least bigger specific gravity than that of the developer is used, and a ratio occupied by the cross-sectional area of member for preventing the developer from adhering with respect to the area of the aperture part is desired to be <= 10% in order not to prevent the movement of the developer at the aperture part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a developing device used in an electrophotographic device or the like, and particularly to a developing device having a stirring and conveying means for developer.

[Prior Art] Conventionally, as a developer stirring and conveying means used in a developing device, a plurality of annular elliptical plates 2 arranged on a rotating shaft as shown in FIG. 5(A) can be cited. Such developer stirring and conveying means has the advantage that developer conveyance and developer amount distribution are effectively made uniform.

1 Invention or problem to be solved M] However, in the above conventional example, a developer with high cohesiveness,
In particular, when using a developer with an average particle size below 1, the developer gets clogged between the elliptical plates 2 and the opening 6 of the elliptical plates 2, reducing the agitation and conveyance ability. There was a problem in that it no longer fulfilled its role in conveying the developer and making the distribution of the amount of developer uniform.

When such a phenomenon occurs, the distribution of the amount of developer in the longitudinal direction of the developing device becomes non-uniform, resulting in problems such as some images not appearing or becoming thinner.

In particular, if the developer is not replenished uniformly in the longitudinal direction of the developing device, or if the amount of developer in the developing device is low,
Problems tend to occur when the amount of developer is detected at the longitudinal end of the developing device M.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a developing device free from image defects caused by developer adhering to the developer agitation and conveyance means.

[Means for Solving the Problems] According to the present invention, the above object is to provide a developer container for storing a developer, a developer carrier disposed at a front opening of the developer container, and a developer container for storing the developer. In a developing device having a developer agitation and conveyance means which is rotatably disposed inside a container and which agitates the developer and conveys the developer in the longitudinal direction of the developer carrier, the developer is attached to the developer agitation and conveyance means. This is achieved by having a vibration impact member that applies vibration or impact to the developer.

[Operation] According to the present invention, the developer stirring and conveying means conveys the developer in the longitudinal direction of the developer carrier without stirring the developer. death·
Therefore, if the fluidity of the developer decreases, a portion of the developer will adhere to the developer stirring and conveying means. Then, when vibration or vfIllK is applied to the developer by the vibration impact member, the adhered developer is loosened and transported again. Therefore, the agitation and conveyance ability of the developer is maintained and a good image is provided.

[Example] First to third embodiments of the present invention will be described based on the accompanying drawings.

First embodiment> First, a first embodiment of the present invention will be described with reference to FIG.

FIGS. 1A and 1B show the developer agitation and conveyance means of the stirrup according to the present embodiment, in which a plurality of annular elliptical plates 2 are arranged in the axial direction of the rotating shaft 1. The annular elliptical plates 2 are attached at a predetermined angle with respect to the rotation axis 1, and are arranged in parallel in the direction of the rotation axis. In FIG. 1, assuming a plane perpendicular to the plane of paper and parallel to the axis of rotation, the outer circumferential lines of the elliptical plates projected onto the plane overlap with adjacent elliptical plates, or the area of the overlapping region is: It is set to be about 40% of the area surrounded by the outer circumference of one elliptical plate.

Such an elliptical plate 2 is disposed in a developing device shown in FIG. 1, and conveys the developer T in the longitudinal direction of the developer container 3 without stirring it. The developer T is adsorbed by a developer carrier 4 containing Macnet, coached into a thin layer by a developer layer thickness regulating member 5, and conveyed to a position facing a latent image carrier (not shown). and then subjected to development. Therefore, in order to obtain a good image, the distribution of developer in the longitudinal direction must be uniform. It is kept uniform over the direction.

That is, the developer (2) is moved to the left and right by the peripheral edge of the elliptical plate 2, and the developer repeats free fall at the opening 6.

On the other hand, if the fluidity of the developer decreases, the developer will adhere to and grow on the elliptical plate 2, and in the worst case, the opening 6 will be filled with developer, and it will no longer contribute to the agitation and conveyance of the developer. found.

Therefore, as shown in FIGS. 1(A) and 1(B), a circle 4iI7 was movably provided on the vibration side [1 material] to prevent developer from adhering to the opening part 6 of the elliptical plate 2. As the rod 7 rotates, the round rod 7 moves around inside the opening 6 under its own weight, loosening the developer by vibration impact, and the developer does not adhere to the opening 6, so that a good agitation and conveyance ability is always maintained. It turned out that.

3. Vibration impact falls through the developer due to gravity, so use a material with a specific gravity that is at least greater than the specific gravity of the developer. It is desirable that the cross-sectional area of the developer adhesion prevention member be 10% or less.

<Second Embodiment> Next, a second embodiment of the present invention will be described using FIG. 3. Note that the same reference numerals are given to the same parts as in the first embodiment, and the explanation thereof will be omitted.

In this embodiment, a protrusion 8 is provided on the elliptical plate 2 of a portion of the developer carrier 4 outside the image area, and a leaf spring 9 is provided on the side of the developer container 3.
By bringing it into contact with the developer, it gives vibration and prevents the developer from adhering.

This embodiment can also achieve the same effects as the first embodiment.

<Third Embodiment> Next, a third embodiment of the present invention will be described using FIG. 4. Note that the same reference numerals are given to the same parts as in the first embodiment, and the explanation thereof will be omitted.

This embodiment differs from the first embodiment in that vibration is applied to the elliptical plate 2 in the direction of the rotation axis.

First, when a developing device drive signal is input, the elliptical plate rotary gear 10 or a solenoid (not shown) pushes in the direction of arrow C and meshes with the elliptical plate gear 11 to drive the elliptical plate 2.

Next, when the developing device stops, the input to the solenoid is cut off, so the push/return spring 12 causes the elliptical plate rotating gear 1 to
0 returns to the position shown in FIG. At this time, the elliptical plate 2 also moves in the axial direction, and vibration is applied to the stopped elliptical plate 2.
The developer attached to the elliptical plate 2 can be removed.

Further, this embodiment has the advantage that vibration can be easily applied at any time by turning the solenoid ON/OFF.

[Effects of the Invention] As explained above, according to the present invention, by using the vibration impact member, the uneven distribution of the amount of developer can be achieved without reducing the ability of the developer agitation and conveyance means to agitate and convey the developer. We were able to solve the problems of image deletion and density unevenness due to poor developer transport.

The present invention is particularly useful when using a developer with a highly cohesive average particle size of less than 1 in 10, or when there is a restriction on the position of the developer supply port, and the developer transport capacity is high. If required, or to limit the amount of developer supplied, a developer amount detection sensor is installed at the end of the developing device, and in order to increase its responsiveness, the developer agitation and conveyance capacity is high. Significant effects can be seen when required.

[Brief explanation of drawings]

FIG. 1(A) is a front view of the developer agitation conveyance means and vibration impact member in the first embodiment of the present invention, FIG. 1(B) is a side view of FIG. 1(A), and FIG. FIG. 83 is a sectional view showing a schematic configuration of a device according to a first embodiment of the invention, FIG. 83 is a sectional view showing a schematic configuration of a device according to a second embodiment of the invention, and FIG. Partially cutaway sectional view shown in Figure 5 (A
) is a front view of a conventional developer agitation conveyance means, and FIG.
) is a side view of FIG. 5(A). 2... Annular elliptical plate (developer agitation conveyance means) 3.
...Developer container 4 ...Developer carrier 7 ...Round bar (vibration impact member) Patent applicant Canon Corporation (A) Fig. 5 (B)

Claims (2)

[Claims] (1) A developer container that accommodates developer, a developer carrier disposed at the front opening of the developer container, and a developer carrier disposed rotatably inside the developer container while stirring the developer. A developing device including a developer agitation conveyance means for conveying the developer in the longitudinal direction of the developer carrier, the development device comprising a vibration impact member that applies vibration or shock to the developer attached to the developer agitation conveyance means. A developing device characterized by: (2) The developing device according to claim 1, wherein the developer stirring and conveying means has a plurality of annular ellipsoidal plates supported by a rotating shaft and arranged in the axial direction.