JPH0538651U - A developer stirring device provided in the developing device - Google Patents

Abstract

(57) [Summary] [Structure] The developer stirring device of the present invention comprises a stirring roller 1 and a developer guide plate 2. Protrusions 20 are provided at both ends of the stirring roller at regular intervals. A movable piece 21 that can abut is provided, and an elongated hole 22 formed in the movable piece 21.
A support rod 11 of the developer guide plate 2 extends through the inside. According to this apparatus, since the developer guide plate 2 vibrates up and down in association with the rotation of the stirring roller 1, even in the case where the fluidity of the developer is lowered as in the high temperature and high humidity condition, the developer guide plate 2 is kept in the developing apparatus. It is possible to effectively mix and agitate and supply the developer without causing the bias of the developer.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a developer stirring device provided in a developing device of an electrostatic photography device such as a copying machine.

[0002]

[Prior art]

 Generally, a developing device of an electrostatic photography apparatus such as a copying machine is provided with a developing roller having a magnet inside at a position facing a surface of a photoconductor, and a doctor blade with a minute gap from the developing roller surface. Is provided. That is, the developer is conveyed in the form of a magnetic brush by the developing roller, and the brush length of the magnetic brush of the developer is adjusted to a certain length by the doctor blade. The electrostatic latent image formed on the body surface is developed.

The conventional developing device as described above is provided with a developer stirring device including a stirring roller and a developer guide plate located above the stirring roller. That is, the developer guide plate is located near the doctor blade and guides the developer scraped from the surface of the developing roller by the blade onto the stirring roller. Triboelectric charging, supplying the developer onto the developing roller, and remixing the developer collected from the surface of the developing roller are performed.

[0004]

[Problems to be solved by the device]

 However, in the conventionally known developer agitator, when environmental conditions such as humidity change and the fluidity of the developer decreases, it is impossible to uniformly guide, mix, and agitate the developer as described above. There is a problem that the developer is unevenly distributed in the apparatus.

As a solution to such a problem, for example, Japanese Patent Laid-Open No. 62-50860 discloses a developer stirring device capable of adjusting the angle of a straightening plate provided on a developer guide plate. Has been done. However, in such an apparatus, since the angle of the straightening plate is adjusted by using a drive source different from the drive source of the stirring roller, the configuration of the apparatus becomes complicated and the power consumption becomes large. is doing.

Therefore, an object of the present invention is to develop a developer with a very simple structure and without using a special driving source even when the environmental fluid such as humidity is changed and the fluidity of the developer is lowered. It is an object of the present invention to provide a developer agitator capable of uniformly and effectively performing agent guidance, mixing, triboelectric charging and the like.

[0007]

[Means for Solving the Problems]

 According to the present invention, in a developer stirring device provided in a developing device including a stirring roller and a developer guide plate disposed above the stirring roller, a constant stirring force is applied to both ends of the stirring roller in the circumferential direction. A plurality of protrusions are provided at intervals, and a movable piece that moves up and down by contact with and release of the protrusion is provided corresponding to the positions of both ends of the stirring roller. And a support rod extending through the elongated hole of the driving piece is provided at both ends of the developer guide plate, and the developer guide plate is rotated according to the rotation of the stirring roller. There is provided a developing agent agitator characterized by vertically moving.

[0008]

[Action]

 That is, according to the present invention, the movable piece rises due to the contact with the projection in association with the rotation of the stirring roller, and the developer guide plate rises in conjunction with the rise of the movable piece. Further, when the contact between the movable piece and the protrusion is released, the movable piece and the developer guide plate descend due to their own weight. Therefore, since the above-mentioned plurality of protrusions are provided at both ends of the agitating roller, the contact between the movable piece and the protrusion and its removal are alternately repeated by the rotation of the agitating roller, and the developer guiding The plate will vibrate up and down. As a result, for example, even when the humidity becomes high and the fluidity of the developer is lowered, it is possible to uniformly and effectively guide (flow) the developer, agitate, and the like.

[0009]

【Example】

 The present invention will be described below based on specific examples shown in the accompanying drawings. Referring to FIG. 1 which shows a side sectional view of a developer stirring device of the present invention and FIG. 2 which shows only one end thereof, the device basically comprises a stirring roller 1 and a developer guide plate 2. ing.

The agitating roller 1 is provided with an agitating blade 5 on its surface so that the developer can be effectively mixed and agitated and the developer can be supplied to the current image roller. Further, at both ends of the stirring roller 1, a frame 6 is provided integrally with the roller 1. Further, on the developer guide plate 2, a plurality of flow straightening plates 10 are provided at predetermined intervals so that the flow of the developer can be smoothly dispersed. The developer guide plate 2 has a left end facing a doctor blade (not shown) located on the developing roller in FIG. 1, and is inclined so that the right end thereof faces downward. The developer scraped off by the blade is pivotally attached to the machine frame of the apparatus, flows along the arrow line A, and is supplied onto the stirring roller 1 described above so that the mixing is effectively performed. There is.

According to the present invention, first, the projections 20 are formed at regular intervals on the frame 6 provided at both ends of the stirring roller 1, and the movable pieces 21 are further provided on the frame 6. It will be provided. That is, the movable piece 21 is always in contact with the frame 6 due to its own weight, and the contact between the movable piece 21 and the protrusion 20 and its release can be repeated in conjunction with the rotation of the stirring roller 1. Then, the movable piece 21 moves up and down. Further, a long hole 22 is formed in the movable piece 21, and the support rods 11 provided at both ends of the developer guide plate 2 extend through the long hole 22. It is understood that the developer guide plate 2 moves up and down as the movable piece 21 moves up and down in association with the rotation of the stirring roller 1. In this case, the downward movement of the developer guide plate 2 is caused by its own weight, but in order to perform this downward movement quickly and smoothly, the support rod 11 is urged downward. It is also possible to install different springs.

In the developer agitating device of the present invention described above, the contact and the release of the movable piece 21 and the protrusion 20 can be smoothly performed without impairing the rotation of the agitating roller 1. is necessary. For example, as shown in FIG. 1, the shape of the protrusion 20 is set so that the step between the protrusion 20 and the frame 6 continuously decreases on one side according to the rotating direction of the stirring roller 1.

[0013]

[Effect of the device]

 According to the present invention, since the developer guide plate moves up and down in conjunction with the rotation of the stirring roller, a special drive source is provided even under conditions such as high temperature and high humidity where the flowability of the developer decreases. Without this, it is possible to uniformly and effectively mix and stir the developer and supply the developer to the developing roller with an extremely simple configuration. Further, as the developer guide plate vibrates up and down, it is not necessary to increase the inclination angle of the guide plate, and the height of the developing device can be reduced. Further, since the flow of the developer is not impaired even if the length of the inner plate is increased, the developer can be transported far from the blade for scraping the developer.

[Brief description of drawings]

FIG. 1 is a side sectional view of a developer stirring device of the present invention.

FIG. 2 is a front view showing one end portion of the apparatus shown in FIG.

[Explanation of symbols]

 1 stirring roller 2 developer guide plate 20 protrusion 21 movable piece

Claims (1)

[Scope of utility model registration request] 1. A developer stirring device provided in a developing device comprising a stirring roller and a developer guide plate arranged above the stirring roller, wherein both ends of the stirring roller are circumferentially spaced at regular intervals. A plurality of protrusions are provided, and a movable piece that moves up and down by contact with and release of the protrusion is provided corresponding to the positions of both ends of the stirring roller. Support rods that are formed and that extend through the elongated holes of the drive piece are provided at both ends of the developer guide plate, and the developer guide plates are provided in accordance with the rotation of the stirring roller. A developer agitating device which moves up and down.