JPH0594856U - Development device - Google Patents

Abstract

(57) [Abstract] [Purpose] In the toner agitator of the developing device for the electrophotographic apparatus, rotation by the toner that has entered into the gap between the shaft hole and the rotation shaft of the bearing body for the rotation shaft to which the drive shaft is not connected This is to present a structure in which the shaft can be locked and toner leakage from a gap exposed to the outside can be prevented by a simple structure. [Structure] A bearing body (1 with a shaft hole having a bottomed shaft hole (10a)
0) is provided in the toner storage hopper (2), and one end of the bearing body (10) is opened to the bottomed bearing (10a) surface in the radial direction of the bearing body (10) and the other end is the bearing body (10). ) Has a simple structure provided with a toner escape groove (10b) opening on the outer surface of the rotary shaft (5a) by dropping toner entering the gap between the bearing and the rotary shaft from the toner escape groove (10b).
Prevents locks and the like.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a developing device for an electrophotographic apparatus, and more particularly to a support structure for an agitator shaft.

[0002]

[Prior Art]

 As a developing device for an electrophotographic apparatus for supplying toner to the surface of a photoconductor drum on which an electrostatic latent image is formed to visualize the latent image, a developing device having a structure as shown in the side sectional view of FIG. The device is widely used. In this developing device, a toner hopper (2) for storing toner (1) and a photoconductor drum (3) whose roller surface rotates in the direction of arrow A in the figure are provided in the opening of the hopper (2) for storing toner. And a developing roller (4) consisting of a cylindrical sleeve (4a) and a magnet roller (4b) therein, which is rotated by a drive source (not shown) in the direction of arrow B in FIG. The toner (1) composed of a carrier and powder, which is rotated in the direction of arrow C in the figure by the drive shaft (9) connected to the rotary shaft (5a) of the carrier and is stored in the storage hopper (2). ) Is agitated, and the toner (1) is fed onto the surface of the photoconductor drum (3) by an agitator (5) and a developing roller (4) for supplying the toner (1) to the vicinity of the current image roller (4). ) To keep the amount of hopper constant 6) and the like.

[0003]

[Problems to be solved by the device]

 However, the above-mentioned conventional developing device has the following problems to be solved. That is, in the conventional apparatus, as shown in the sectional side view of FIG. 4, the left and right rotating shafts (5a) of the agitator (5) are provided on the left and right side walls (2a) of the toner storage hopper (2). After being inserted into the through shaft hole (7a) of (7), the E ring (8) is fitted and supported in the annular groove (5b) provided at the protruding end of the rotary shaft (5a), and The drive shaft (9) connected to the rotary shaft (5a) is used for rotation. Therefore, there is no choice but to allow a slight gap G between the through shaft hole (7a) of the bearing body (7) and the rotary shaft (5a). Therefore, it is not possible to prevent the fine toner (1) from entering the gap G during use. Therefore, the rotation of the agitator (5) may be irregular, or the rotation shaft may be locked to stop the agitator (5), resulting in poor image quality and failure of development. Further, since the gap is exposed to the side wall (2a) of the toner storage hopper (2), the toner (1) leaks to the outside to contaminate the surroundings and waste toner. Therefore, conventionally, a special mechanism (not shown) is provided on the left and right bearing bodies to prevent the rotation of the agitator as described above. However, this increases the cost.

[0004]

【Purpose】

 The object of the present invention is to reduce the cost by presenting a simple structure capable of preventing the clogging of the toner on one of the bearings to which the drive source is not connected.

[0005]

[Means of the Invention for Solving the Problems]

 The purpose of the present invention is to provide the following means: (a bearing body having a bottomed shaft hole for the bearing shaft hole of one agitator rotation shaft to which the drive shaft is not connected is provided on one wall of the toner storage hopper; In the radial direction of the bearing body, one end is opened into the bottomed shaft hole, and the other end is provided with a toner escape groove which is opened to the outer surface of the bearing body.

[0006]

[Action]

 If the shaft hole of the bearing body is bottomed as described above and the bearing body is provided on the toner storage hopper wall, the gap between the rotating shaft of the agitator and the shaft hole may be exposed on the outer wall of the hopper. Absent. Therefore, it is possible to reliably prevent the toner from leaking through the gap. Even if toner enters the gap between the rotating shaft and the shaft hole, it is scraped off by the corner of the toner escape groove that contacts the rotating shaft surface every time the rotating shaft surface of the agitator is located at the opening of the toner escape groove. Then, the toner falls into the toner escape groove and is returned to the toner storage hopper. Therefore, it is possible to reliably prevent the occurrence of a failure such as the toner clogging the gap between the rotary shaft and the bearing body, which renders the agitator incapable of rotating. Therefore, the bearing body on the side to which the drive source is not connected can be made inexpensive, and the manufacturing cost can be reduced accordingly.

[0007]

【Example】

 Next, a bearing assembly according to the present invention will be described with reference to the drawings. 1 (a), (b) and (c) are a front view and a side view showing a structure of a bearing body on a side to which a drive shaft according to the present invention is not connected, and a side view showing a state in which a rotary shaft of an agitator is supported. is there. 1 (a) and 1 (b), (10) is a bearing body according to the present invention, which includes the following parts. (10a) is a bottomed shaft hole, and (10b) is a toner escape groove provided at equal intervals in four radial directions, each of which has a radial end of the bearing body (10) with a bottomed end. The bearing (10a) and the outer peripheral surface of the bearing body (10) are opened from the inlet of the shaft hole (10a) of the bearing body (10) to substantially the entire length of the bottom. This bearing body (10) is integrally formed on one wall (2a1) of the toner storage hopper (2) as shown in FIG. 1 (c), for example, by molding a synthetic resin material, and its shaft hole is formed. By inserting the rotating shaft (5a) into the (10a), one end of the agitator (5) is supported. Incidentally, (5c) is a washer for adjusting the insertion depth of the rotating shaft (5a), and (10c) is a support member integrally formed with the bearing body (10). By doing so, not only can the toner (1) from the bearing portion on the side to which the drive shaft is not connected be prevented from leaking to the outside by the bearing body having a simple structure, but also the toner that has entered the gap G can be prevented. Since (1) is dropped into the hopper (2) through the toner escape groove (10b) as shown in FIG. 1 (c), the agitator (5) cannot be prevented from rotating. Although the case where four toner escape grooves (10b) are provided has been described above, the number and width of the grooves are selected in consideration of the toner escape condition and the strength of the bearing body. The toner escape groove (10b) may be slanted as shown in FIG. 2 (a), and the toner escape groove (10b) located above as shown in FIG. 2 (b) (c) may be omitted. You may.

[0008]

[Effect of the device]

 According to this invention, since the bearing body on the side where the drive shaft is not connected can be easily constructed, toner leakage, rotation of the rotating shaft, etc. can be prevented by using an expensive special mechanism for the bearing bodies at both ends as in the past. It is possible to obtain an excellent effect that the manufacturing cost can be reduced as compared with the one that aims at.

[Brief description of drawings]

FIG. 1 is an explanatory view of a bearing body according to the present invention.

FIG. 2 is an explanatory view showing another example of a bearing body according to the present invention.

FIG. 3 is an explanatory diagram of a developing device.

FIG. 4 is an explanatory view of a conventional method for supporting an agitator rotary shaft by a bearing body.

[Explanation of symbols]

 (1) Toner (2) Toner storage hopper (2a) Toner storage hopper side wall (2a1) Toner storage hopper inner wall (3) Photoconductor drum (4) Developing roller (5) Agitator (5a) Rotating shaft (5b) Annular groove (5c) Washer (6) Hopper (7) Bearing body (7a) Through shaft hole (8) E ring (9) Drive shaft G Gap between shaft hole and rotating shaft (10) Bearing body (10a) Bottomed shaft hole (10b) Toner escape groove

Claims (1)

[Scope of utility model registration request] 1. A developing device for an electrophotographic apparatus, comprising a developing roller, a toner agitator and the like in a toner storage hopper, wherein a bearing shaft hole for a rotary shaft of the toner agitator is a bottomed shaft hole. The bearing body is provided on one wall of the toner storage hopper, and one end of the bearing body in the radial direction is opened to the bottomed bearing surface and the other end is opened to the outer surface of the bearing body. Is provided to support one end of the agitator rotation shaft on the side not connected to the drive shaft.