JPH0580652A - Developing device and color image forming device - Google Patents

Abstract

(57) [Abstract] [Purpose] A developing device capable of stably supplying a developer with a simple structure even when the developing device is formed flat in the thickness direction, and a color using the same. An object is to provide an image forming apparatus. A plate-shaped ladder 9 is arranged in the toner storage chamber 42, and a plurality of holes 9 are formed on the surface facing the bottom surface of the toner storage chamber 42.
b is provided. Further, the crank-shaped drive shaft 10 is inserted into the elongated hole 91 formed at the tip portion. As a result, the forward path is brought into sliding contact with the bottom surface, and the return path is separated from the bottom surface of the ladder 9.
Is operated so that the toner on the inner side of the toner storage chamber 42 is gradually conveyed forward.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device used in a recording device such as an electrophotographic copying machine and a printer, and a color image forming apparatus using the developing device.

[0002]

2. Description of the Related Art Conventionally, a developing device used in an electrophotographic image forming apparatus has a developing sleeve, which is a developer carrying member, in a front opening of a toner container, which is a developer container. Is divided into a developing chamber in which the developing sleeve is arranged and a toner storing chamber for storing toner as a developer through a communication opening. And FIG.
As described above, by configuring the toner storage chamber 17b substantially above the developing chamber 17a, the toner is supplied into the developing chamber 17a by its own weight, or the toner storage chamber 18b is replaced with the developing chamber 18a as shown in FIG. The toner is developed in the developing chamber 18 by the stirring blade 19 which is a substantially horizontal position and is a stirring and conveying member.
It was supplied in a. Further, in such an apparatus, a control method has been implemented in which the toner supply amount into the developing chamber 17a is made constant by intermittently driving the toner intermittent supply means 20 as shown in FIG.

[0003]

However, a color image forming apparatus in which a plurality of developing devices are arranged around the photosensitive drum and a full-color image is formed by using toners of a plurality of colors such as yellow, magenta, cyan, and black. Small size
When the structure is made lightweight, it is necessary to flatten the developing device itself in the thickness direction, and it has been difficult to sufficiently supply the toner to the developing chamber side by the above-described conventional toner supplying method.
As a method for solving this problem, it is conceivable to arrange a plurality of stirring blades 22 in the toner storage chamber 21 as shown in FIG. 10 and drive these to supply the toner, but in this method, the toner container is The flatter it becomes in the thickness direction, the more the number of stirring blades has to be increased, and there is a problem that the cost increases with the disposition of the drive mechanism.

As another method, it is conceivable that the developing device 23 is arranged upside down above the photosensitive drum 24 as shown in FIG. 11 and the toner is supplied by its own weight. Therefore, it is difficult to carry out this method because toner scatters and spills easily occur and there is a high risk of soiling the image.

Further, as another method, as shown in FIG. 12, the toner in the toner accommodating chamber 25 is developed by using the toner pushing member 26 disposed in the toner container 25 while being biased by the spring 27 or the like. A method of supplying the toner to the toner has been proposed, but the length of the toner container is limited because the stroke of the spring cannot be extremely long, and it is difficult to stably supply the toner. Too much development room 2
There was a problem in that the toner aggregated in No. 8 and a good image could not be obtained.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and a developing device capable of conveying a sufficient amount of toner to a developing chamber with a simple mechanism even when the developing device is flat, and a color using the same. An object is to provide an image forming apparatus.

[0007]

SUMMARY OF THE INVENTION According to the present invention, the above-mentioned object is, firstly, regarding the developing device, the inside of which is divided into a front developing chamber and a rear developer accommodating chamber through a communication opening. A developer container, a developer carrier rotatably arranged in an opening formed in front of the developing section, and a reciprocatingly arranged reciprocating member in the developer accommodating section, and the developer from the developer accommodating chamber. In a developing device having a developer supply means for supplying a developer to a chamber through the communication opening, the developer supply means includes a plate-like body slidably in contact with a bottom surface of the developer accommodating chamber and the plate. And a driving member that reciprocates the plate-like body to and from the developer carrying body, and the plate-shaped body is provided on a surface facing the bottom surface of the developer accommodating chamber. Grooves or holes that surround the developer are formed. In the return path, at least the front end portion of the plate-like body on the developing chamber side is swingably attached to the drive member so as to move away from the bottom surface. In the case of a color image forming apparatus, a plurality of the above-mentioned developing apparatuses are arranged around the latent image bearing member, and each developing apparatus stores a developer of a different color.

[0008]

According to the present invention, in the reciprocating developer supplying means provided with the plate and the driving member, first, the plate comes into sliding contact with the bottom surface of the developer accommodating chamber in the outward path toward the developing chamber side. To move. Therefore, the groove or hole formed in the surface of the plate-like member facing the bottom surface advances while enclosing the developer, and conveys the developer on the inner side of the developer accommodating chamber to the developing chamber side. Further, the developer around the front end of the plate-shaped body on the side of the developing chamber is also pushed by the front end and supplied from the developer accommodating chamber to the developing chamber. Next, in the return path, the plate-like body moves so as to be separated from the bottom surface, so that the developer conveyed to the front side in the outward path returns to the initial position without returning to the inner side of the developer accommodating chamber. Thus, the developer on the inner side of the developer accommodating chamber is gradually conveyed to the front side of the developing chamber,
The sheet is supplied into the developing chamber by the front end of the plate.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First to third embodiments of the present invention will be described with reference to the drawings.

<First Embodiment> First, a first embodiment of the present invention will be described with reference to FIGS. 1 in FIG.
Is a photosensitive drum that is a latent image carrier, and is arranged so as to be driven clockwise by a drive source (not shown). A charger 2 is provided above the photosensitive drum 1, and the charger 2 uniformly charges the photosensitive drum 1. The charged surface of the photosensitive drum 1 is exposed by an exposure source 3 disposed above the charger 2, and an electrostatic latent image is formed on the surface. On the other hand, the developing sleeve 5, which is a developer carrying member rotatably carried by the developing device 4, is arranged so as to face the photosensitive drum 1.
The photosensitive drum 1 is driven counterclockwise by the same or different drive source. Then, the developing roller 5 is disposed so as to contact the developing sleeve 5, and the coating roller 6 that is driven counterclockwise in conjunction with the driving of the developing sleeve 5 is also disposed so as to contact the developing sleeve 5. A thin layer of the toner T as a developer is applied to the developing sleeve 5 by the blade 7. Since the toner T is charged by friction, a bias voltage is applied to the developing sleeve 5 using the developing bias power source 8 to adhere to the electrostatic latent image portion formed on the surface of the photosensitive drum 1,
So-called reversal development is performed.

In the apparatus of this embodiment as described above, the developing device 4 has a toner container 40 which is a developer container, and the toner container 40 comprises a developing sleeve 5, a coating roller 6 and a blade 7. It is divided into a front developing chamber 41 and a rear toner accommodating chamber 42 via a communication opening 11.

The bottom portion of the toner accommodating chamber 42 is formed with a smooth curved surface portion 42a and is connected to the communication opening 11, and a ladder 9 serving as a developer supplying means disposed in the toner accommodating chamber 42 is used. The toner in the storage chamber is conveyed to the front development chamber.

The ladder 9 is composed of a plate-shaped toner holding portion and a shaft mounting portion for axially supporting the toner holding portion, and elongated holes 91 are formed on both side surfaces of the shaft mounting portion. The crank portion 10a of the drive shaft 10 is inserted. Further, the toner holding portion is provided with holes 9b formed along the axial direction of the drive shaft 10 at a plurality of positions at predetermined intervals.

Therefore, when the drive shaft 10 is rotated clockwise by a drive source (not shown), the ladder 9 moves along the curved surface portion 42a of the bottom portion of the toner accommodating chamber 42 to reach the bottom portion of the toner accommodating chamber 42. The accumulated toner T is pushed by the tip 9a of the ladder 9 or surrounded by the hole 9b and the bottom of the toner storage chamber 42 and transferred to the communication opening 11 side. When the tip portion 9a of the ladder 9 reaches the curved surface portion 42a, the tip portion 9a moves along the curved surface portion 42a, so that only the front and rear ends of the ladder 9 come into contact with the bottom portion of the toner storage chamber 42, and the hole portion 9b and the toner are The toner T surrounded by the bottom of the storage chamber 42 is left there,
The toner T pushed by the tip 9a is further transported to the communication opening 11 side along the curved surface 42a. Then, as shown in FIG. 2, the tip 9 a of the ladder 9 is connected to the lower end 1 of the communication opening 11.
When reaching 1a, the toner T pushed by the tip portion 9a falls to the developing chamber 41 side, and the toner T is supplied into the developing chamber.

When the drive shaft 10 further rotates, the weight of the rudder 9 causes one end portion 91a of the elongated hole 91 to fit with the crank portion 10a as shown in FIG. 3, and the rudder 9 is returned to the initial position. At this time, the tip 9a of the ladder 9 moves away from the bottom of the toner storage chamber 42, so that the toner T transferred to the communication opening 11 side by the above-described movement and accumulated on the bottom of the toner storage chamber 42 is stored again in the toner. The ladder 9 can return to the initial position without being transferred to the inner side of the chamber 42.

With the above-mentioned structure, the toner in the toner accommodating chamber, which is flat in the thickness direction, can be satisfactorily supplied to the developing chamber side by one toner supplying means, and at the same time, the toner supplying means moves back. It is also possible to stir the toner accumulated in the middle layer portion or the upper layer portion of the toner storage chamber.

Although the present embodiment is suitable for the developing device as a cartridge which is fixedly arranged or detachable in the image forming device, since the developing device can be flattened as described above, as shown in FIG. A plurality of developing devices of this embodiment are arranged around the photosensitive drum 1, and toners of different colors such as yellow, magenta, and cyan are stored in each developing device, thereby forming a small color image forming apparatus. be able to. In addition, as shown in FIG.
Y, 4M, 4C, photosensitive drum 1, cleaning device 16
It is also easy to form a cartridge C in which the above components are integrally configured and which can be attached to and detached from the image forming apparatus.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, as shown in FIG. 6, the guide pin 12 provided on the side surface of the ladder 9 ′ and the guide groove 13 provided on both side walls of the toner storage chamber 42 ′ are fitted to each other to move the ladder 9 ′. Is an example in which the guide groove 13 is arranged along the guide groove 13.

In particular, in this embodiment, the guide pin 12b is also provided at the rear end of the ladder 9'and the guide groove 13b is fitted in the guide pin 12b. Therefore, not only the behavior of the toner supply means can be regulated, but also The toner T deposited on the inner side of the toner storage chamber 42 'can also be satisfactorily conveyed.

<Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIG. The same parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, as shown in FIG. 7, the drive member of the toner supplying means is an agitating blade having a drive shaft and cam members at both ends of the drive shaft. In this embodiment, the elongated holes 91 ″ formed on the side surfaces of both ends of the ladder 9 ″ and the cams 15 formed on both ends of the stirring blade 14 are fitted together. The rudder 9 ″ moves in the same manner as in the first embodiment by the guide of the tip portion 15 a of the cam 15, but in the case of this embodiment, a thin resin sheet made of resin extending in the longitudinal direction of the stirring blade 14 is used. The blade member 14a supplies the toner T to the developing chamber 41 "side, and the ladder 9" has only a function to convey the toner in the inner side of the toner accommodating chamber 42 "to the communication opening 11" side. ..

With such a structure, for example, as compared with the structure of the first embodiment, the communication opening 11 ″ has the toner accommodating chamber 4.
Even when it is located considerably above the bottom of the 2 ", the ladder 9" can be operated smoothly and the toner T can be stably supplied to the developing chamber 41 ".

[0022]

As described above, according to the present invention,
A plate-shaped body and a driving member for reciprocating the plate-shaped body are provided as a developer supplying means, and a groove or a hole is formed on the surface of the plate-shaped body facing the bottom of the developer accommodating chamber to form the plate-shaped body. Since it is mounted so as to move in sliding contact with the bottom surface on the outward path and to move away from the bottom surface on the return path, a stable developer supply in a flat developing device in the thickness direction can be simply configured. Can be achieved with. Further, by using the developing device having the above-described configuration, it becomes easy to dispose a plurality of developing devices around the latent image carrier having a small diameter, so that a small color image forming apparatus can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which the plate-shaped member of the developer supply unit has reached the foremost position on the outward path in the apparatus shown in FIG.

FIG. 3 is a cross-sectional view showing a state in which the plate-shaped member of the developer supply unit is located in the middle of the return path in the apparatus of FIG.

FIG. 4 is a sectional view showing a schematic configuration of a color image forming apparatus using the apparatus of FIG.

5 is a cross-sectional view showing a schematic configuration of a cartridge in which the apparatus of FIG. 1 and a latent image carrier and the like are integrally configured.

FIG. 6 is a cross-sectional view showing a schematic configuration of a second embodiment device of the present invention.

FIG. 7 is a sectional view showing a schematic configuration of a third embodiment device of the present invention.

FIG. 8 is a cross-sectional view showing a schematic configuration of a conventional example device in which a developer accommodating chamber is arranged above the developing chamber.

FIG. 9 is a cross-sectional view showing a schematic configuration of a conventional apparatus in which a developer accommodating chamber and a developing chamber are arranged substantially horizontally.

FIG. 10 is a cross-sectional view showing a schematic configuration of a conventional apparatus in which a developer container is flat in the thickness direction.

FIG. 11 is a cross-sectional view showing a schematic configuration of a conventional device in which a developer device is arranged substantially perpendicular to a latent image carrier.

FIG. 12 is a cross-sectional view showing a schematic configuration of a conventional device including a developer supply unit using a spring.

[Explanation of symbols]

 5 Development Sleeve (Developer Carrier) 9 Ladder (Developer Supply Means) 10 Drive Shaft (Drive Member) 11 Communication Opening Port 40 Developer Container 41 Development Chamber 42 Toner Storage Chamber (Developer Storage Chamber)

Claims (3)

[Claims] 1. A developer container whose inside is divided into a front developing chamber and a rear developer accommodating chamber through a communication opening, and a rotatably arranged inside an opening formed in front of the developing unit. And a developer supply means that is reciprocally disposed in the developer accommodating portion and that supplies the developer from the developer accommodating chamber to the developing chamber through the communication opening. In the developing device having the above-mentioned developer, the developer supplying means drives the plate member slidably in contact with the bottom surface of the developer accommodating chamber and a driving member for reciprocating the plate member with respect to the developer carrying member. The plate-like body has a groove portion or a hole portion surrounding the developer between the bottom surface and the bottom surface of the developer accommodating chamber. On the return path, so as to move away from the bottom surface. Further, at least the front end portion of the plate-shaped body on the side of the developing chamber is swingably attached to the drive member. 2. The developing device according to claim 1, wherein the driving member of the developer supplying means is provided with a plate-shaped developer stirring and conveying member on the rotation shaft. 3. A color image characterized in that a plurality of the developing devices according to claim 1 or 2 are arranged around a latent image carrier, and each developing device stores a developer of a different color. Forming equipment.