JPH1195546A - Developer layer thickness regulating member and developing device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer layer thickness regulating member which prevents the flocculation and solidification of a one-component developer near to the contact part between a developer carrying member and the developer layer thickness regulating member and a developing device using the same. SOLUTION: This developer layer thickness regulating member 1 is arranged in pressurized contact with the rotatably disposed developer carrier 2 and regulates the layer thickness of the one-component developer T formed on the developer carrier 2. The developer layer thickness regulating member 1 has a contact member 1a which comes into contact with at least the developer carrier 2 and is disposed movably along the rotating direction of the developer carrier 2 and a contact member movement regulating member 1b which regulates the moving range of the contact member 1a between a layer thickness regulation position P1 and a standby position P2 and presses the contact member 1a to the developer carrier 2 in at least the layer thickness regulation position P1.

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 an image forming apparatus such as an electrophotographic copying machine or a printer, and more particularly to a developing device for developing an electrostatic latent image using a one-component developer. The present invention relates to a developer layer thickness regulating member to be used and an improvement of a developing device using the same.

[0002]

2. Description of the Related Art In general, a developing device used in an electrophotographic or copying machine has a developer carrier facing a latent image carrier such as a photosensitive drum, and the developer is carried on the developer carrier. Then, the developer layer thickness is regulated to an appropriate thickness by the developer layer thickness regulating member, and then supplied to the developing area. Conventionally, as a developer layer thickness regulating member of this type, a member formed of a rigid body or an elastic body into a blade shape, a roll shape, or the like, and disposed to face a developer carrier is known. In particular, in an embodiment in which a one-component developer is used as a developer, a type in which a developer layer thickness regulating member is disposed in pressure contact with a developer carrier to regulate the layer thickness is known.

In such a prior art, in the case of using a blade made of a rigid body as the developer layer thickness regulating member, one component staying near the contact portion between the blade made of the rigid body and the developer carrying member is used. The developer solidifies or agglomerates,
As a result, there have been technical problems that toner fogging occurs on black (white) streaks and the background after development, and that density unevenness occurs due to deterioration of the charging function. In order to solve such a technical problem, there is a technique of removing the developer solidified or agglomerated in the vicinity of a contact portion between the blade and the developer carrier by rotating the developer carrier in a non-developing operation. (See Japanese Patent Application Laid-Open No. 4-281478).

[0004]

However, in the above-mentioned prior art, a constant pressure always acts on the contact portion between the blade for regulating the layer thickness and the developer carrier, so that the blade adheres to the blade. There are many one-component developers that are not removed as they are, resulting in a technical problem that the one-component developer adheres to the blade. Further, since the same portion of the blade is always in contact with the developer carrying member at the contact portion (nip portion), there is a technical problem that permanent deformation is easily generated in the blade. Furthermore,
In an embodiment using a rigid blade as the developer layer thickness regulating member, the configuration is often such that a blade member is adhered to a leaf spring material. There is also a technical problem that the regulation of the layer thickness of the developer becomes unstable.

The present invention has been made to solve such a technical problem, and has been devised in which the shape and structure of a developer layer thickness regulating member are devised, and a developer carrying member and a developer layer thickness regulating member are developed. To provide a developer layer thickness regulating member for preventing aggregation and coagulation of the one-component developer in the vicinity of a contact portion with the developer, and a developing device using the same.

[0006]

That is, according to the present invention, as shown in FIG. 1, a developer carrier 2 rotatably disposed.
And a developer layer thickness regulating member 1 for regulating the layer thickness of the one-component developer T formed on the developer carrier 2, wherein the developer layer thickness regulating member 1 is at least A contact member 1a which is in contact with the developer carrier 2 and is movably arranged along the rotation direction of the developer carrier 2, and a movement range of the contact member 1a is defined by a layer thickness regulating position P1 and a standby position P2. And a contact member movement regulating member 1b for regulating the contact member 1a against the developer carrier 2 at least at the layer thickness regulating position P1.

In such technical means, the developer carrying member 2 may be appropriately selected as long as it carries a one-component developer on its peripheral surface. The one-component developer T is, of course, a one-component developer, but it does not matter whether the one-component developer T itself has magnetism.

Furthermore, the contact member 1 of the developer layer thickness regulating member 1
As a, the layer thickness of the one-component developer T formed on the contacting developer carrier 2 is regulated to an appropriate thickness, and when the layer thickness is regulated, the one-component developer T has a sufficient charge. If, for example, the shape, the shape of a plate, a roll, and the like, and the material thereof, metal, plastic, a metal surface layer provided with a coating layer may be appropriately selected. .

The shape and material of the contact member movement restricting member 1b are appropriately selected as long as the contact member 1a can be moved within a predetermined range with respect to the rotational direction of the developer carrier 2. However, in order to maintain good layer regulation performance, it is necessary to regulate the movement of the contact member 1a in the axial direction of the developer carrier 2. In this case, from the viewpoint of simply restricting the movement of the contact member 1a, the contact member movement restricting member 1b is formed into a substantially concave shape, for example, by bending bent pieces at both ends of a channel material having a concave groove. Or a block material is buried, or a concave portion is integrally formed on a flat plate by pressing, for example, the concave portion is opposed to the developer carrier 2 side, and the movement of the contact member 1a is caused by the inner wall of the concave portion. It is preferable to regulate. Further, from the viewpoint of applying a stable pressing force to the contact member 1a, the bottom of the concave portion of the recess of the contact member movement restricting member 1b where the contact member movement restricting member 1b comes into contact with the contact member 1a has elasticity. It is preferred to provide a layer.

Further, when the developer layer thickness regulating member 1 is applied to a developing device, from the viewpoint of preventing the one-component developer T from sticking to the developer layer thickness regulating member 1, the developer carrier 2 is controlled by the developer carrier driving means 3, and during the developing operation, the developer carrier 2 is rotated in a predetermined rotational direction A.
After the development operation is completed, the predetermined direction B is the reverse direction of the rotation direction A.
What is necessary is just to rotate it.

At this time, the period during which the developer carrier 2 is rotated in the reverse direction may be appropriately selected as long as it is a non-development operation between the end of the development operation and the start of the next development operation. From the viewpoint of reliably preventing the one-component developer T from adhering to the contact member 1a, the development is preferably performed immediately after the end of the developing operation. Further, from the viewpoint of avoiding useless reverse rotation cycles, The reverse rotation of the agent carrier 2 causes the contact member 1a, which is arranged in contact with the agent carrier 2, to move in accordance with this movement, and moves to the standby position P2 of the contact member movement restricting member 1b.
And the movement is regulated until the contact member 1a is pressed unnecessarily to the standby position P2. Further, the frequency of the reverse rotation of the developer carrier 2 may be performed each time the developing operation is performed, but is not limited thereto, and may be appropriately selected from a predetermined number of sheets, each job, or the like.

In such an embodiment, the structure and arrangement of the contact member movement restricting member 1b are such that both the layer thickness restricting position P1 and the standby position P2 apply a pressing force to the contact member 1a. Although it does not matter, the contact member 1
From the viewpoint of effectively suppressing the deterioration of the shape of a, the configuration and arrangement of the contact member 1a and the contact member movement restricting member 1b apply a sufficient pressing force to the contact member 1a from the layer thickness regulating position. Further, it is preferable not to apply the pressing force at the standby position.

Next, the operation of the present invention will be described. The contact member 1a is in contact with the developer carrier 2 and is movable along the rotation direction. However, the contact member 1
Since a is restricted from moving outside a certain range by the contact member movement restricting member 1b, the movement of the member a from the layer thickness regulating position P1 to the downstream side and the movement from the standby position P2 to the upstream side are regulated. Will stay in position.

The operation when the developer layer thickness regulating member 1 is applied to a developing device will be described. With the start of the developing operation, the developer carrier driving unit 3 moves the developer carrier 2
Is controlled to rotate in a predetermined rotation direction A, and the developer carrier 2 starts rotating in a predetermined rotation direction A. With the start of rotation of the developer carrier 2 in the predetermined rotation direction A,
The contact member 1a of the developer layer thickness regulating member 1 which is disposed in contact with the developer carrier 2 receives an external force from the developer carrier 2 and moves from the standby position P2 in the same direction as the developer carrier 2 moves. Move in the direction. Then, the movement of the contact member 1a out of the predetermined range is restricted by the contact member movement restricting member 1b, and the contact member 1a stays at the layer thickness regulating position P1.

At this time, a one-component developer T is supplied from a developer supply means (not shown) to an upstream side of a contact portion between the surface of the developer carrier 2 and the developer layer thickness regulating member 1. Then, the developer layer on the surface of the developer carrier 2 is formed to have a constant thickness with the layer thickness being regulated by the contact member 1a of the developer layer thickness regulating member 1, and then the electrostatic latent image (not shown) is developed. I do.

After the end of the developing operation, the developer carrier driving means 3 controls the developer carrier 2 to rotate from a predetermined rotation direction A to a reverse direction B of a predetermined direction. 2 starts rotation in the reverse direction B of the predetermined rotation direction A. With the start of rotation of the developer carrier 2 in the reverse direction B of the predetermined rotation direction A, the contact member 1 a of the developer layer thickness regulating member 1, which is arranged in contact with the developer carrier 2, The developer carrier 2 receives the external force from the body 2 and moves in the same direction as the developer carrier 2 from the layer thickness regulating position. The contact member 1a is restricted from moving outside a certain range by the contact member movement restricting member 1b.
, And stays at the standby position upstream of the developer carrier 2 in the predetermined rotation direction A.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the accompanying drawings. First Embodiment FIG. 2 shows a one-component developing apparatus according to a first embodiment. In FIG. 1, a developing device according to the present embodiment includes a hopper 31 which is opened to face a photosensitive drum 21 carrying an electrostatic latent image 22 and contains a one-component non-magnetic developer T therein.
A developing roll 32 disposed facing the opening of the hopper 31; a developing bias power supply 41 for applying a developing bias voltage to the developing roll 32; Developer stirring and transport rod 33 which transports the one-component non-magnetic developer T to the developing roll 32
A one-component non-magnetic developer T provided downstream of the developing roller 32 in the direction of rotation of the opposing portion of the photosensitive drum 21 and not used for development, is removed from the developing roller 32; A developer releasing supply roll 34 for supplying the new one-component non-magnetic developer T conveyed by the developing roller 33 to the developing roll 32;
A developer regulating member 11 disposed opposite to the developer roll 2 to regulate the developer layer on the development roll 32 to a predetermined thickness;
Developing roller rotation direction switching device 5 for switching the rotation direction of the developing roller
1 is provided.

In this embodiment, the hopper 31
The developing roller 32 and the one-component non-magnetic developer T are disposed so as to cover the developing roller 32 from below. The inside of the hopper 31 is functionally separated into a developing roll housing chamber for housing the developing roll 32 and a developer storing chamber for mainly storing the one-component non-magnetic developer T.

The developing roll 32 is made of, for example, a pipe or a column made of aluminum, stainless steel, or the like. The surface roughness of the developing roll 32 is determined from the viewpoint of ensuring toner transport performance. Ra = 0.2 ~ by performing machining such as sandblasting on the circumferential surface or mechanically polishing the circumferential surface and then performing anodizing treatment.
One having a thickness of about 2.0 μm is used. In particular, in the present embodiment, a round bar of aluminum is used as a material,
The surface roughness is set to Ra = 1.0 μm. Further, an AC power supply 411 and a DC power supply 412 as the development bias power supply 41 are connected to the development roll 32 to perform development.

The developer stirring / conveying rod 33 is, for example, a stirring rod in which a U-shaped arm portion is integrally formed with respect to the rotating shaft, and stirs the one-component non-magnetic developer T. It is transported to the developing roll 32 side.

The developer release supply roll 34 has a configuration in which a coating layer is provided on the outer peripheral surface of a pipe-shaped or cylindrical metal shaft. As the coating layer, it is preferable to use an elastic body to secure a sufficient nip width with the developing roll 32, and to supply a sufficient one-component non-magnetic developer T to the developing roll 32, and after the developing process. Since it is required that the one-component non-magnetic developer T remaining on the developing roll 32 be reliably peeled off, a material having elasticity and high transporting ability is preferable. For example, a foam material is very effective. . In particular, in the present embodiment, the stainless steel shaft has an electric resistance value of about 10 ⁶ Ω · cm and a hardness of 1 in Asuka C hardness.
It is provided with a urethane rubber-based foamed resin layer of about 0 degrees, and its diameter is φ = 16 mm.

In this embodiment, the developer regulating member 11 is disposed in pressure contact with the developing roll 32 as shown in FIG. 3 to reduce the layer thickness of the one-component non-magnetic developer T on the developing roll 32. A regulating blade 111 for regulating, a concave blade holding frame 112 for regulating and holding the regulating blade 111 so as not to be moved out of a predetermined range, and a regulating blade 111 disposed on an inner surface of the blade holding frame 112 to attach the regulating blade 111 to the developing roll 32. And an elastic layer 113 pressed to the side.

Here, the regulating blade 111 is made of a metal such as a SUS plate or the like having a toner charging performance, a plastic, or a metal provided with a coating layer on its surface. In particular, in this embodiment, , Plate-shaped stainless steel is used.

The blade holding frame 112 is formed by bending bent pieces at both ends of a channel material made of, for example, SUS, Al, phosphor bronze or the like having a concave groove. The frame 112a on the downstream side in the predetermined rotation direction A of the developing roll 32 is
1, the frame thickness 112b on the upstream side is at the standby position P2, and the frame pieces (not shown) located at both ends in the axial direction of the developing roll 32 are for moving the regulating blade 111 in the axial direction. Regulating.

The elastic layer 113 is made of a sponge or the like, and applies a pressing force to the regulating blade 111 so as to press the regulating blade 111 and press it against the developing roll 32. Here, the pressing force is set to such an extent that the regulating blade 111 can move with the rotation of the developing roller 32 (2 to 10 g / cm). The elastic layer 113 may be provided so that the distance between the developing roll 32 and the elastic layer 113 decreases toward the downstream side in the predetermined rotation direction A of the developing roll 32.

A developing roll rotation direction switching device 51 is also provided.
Indicates that the developing roller 32 is rotated in the predetermined rotation direction A during the developing operation.
Control the developing roll drive motor 52 to rotate the
On the other hand, the developing roller drive motor 52 is controlled so as to rotate the developing roller 32 in a direction B opposite to a predetermined rotating direction for a certain period immediately after the end of the developing operation. In the present embodiment, the certain period immediately after the end of the developing operation means that when the developing operation is completed and the developing roll 32 is rotated in the reverse direction B of the predetermined rotation direction A, the regulating blade 111 regulates the layer thickness. It refers to a sufficient period from the position P1 to the standby position P2 before being regulated by the blade holding frame 112.

The operation of the one-component developing apparatus according to the present embodiment will be described with reference to FIG. That is, the one-component non-magnetic developer T is transferred to the developer stirring / conveying rod 3 in the hopper 31.
After being stirred by 3, it is conveyed to the developing roll 32 side. With the start of the development, the developer peeling supply roll 34 contacts the developing roll 32 to supply the one-component non-magnetic developer T to the developing roll 32 and, while supplying the one-component non-magnetic developer T to the developing roll 32, moves in a predetermined direction (the direction of the arrow). Rotate at the speed of. The developing roll 32 carrying the one-component non-magnetic developer T on its outer peripheral surface rotates at a predetermined speed in a predetermined rotation direction A, and the one-component non-magnetic developer T has a predetermined layer thickness by the developer regulating member 11. And one-component non-magnetic developer T carried on the surface of the developing roll 32 is given a sufficient charge. And a fully charged one-component non-magnetic developer T
Is developed by a potential difference between a voltage applied to the developing roll 32 by the developing bias power supply 41 and a potential of the electrostatic latent image 22 formed on the photosensitive drum 21 in a portion close to the photosensitive drum 21. . Thereafter, the residual developer not used for the development moves to a contact portion with the developer peeling supply roll 34 with the rotation of the developing roll 32, and is removed from the developing roll 32 by the developer peeling supply roll 34. Is collected in the hopper 31 again.

The operation of the developer regulating member 11 in such a developing operation will be described in detail. At the start of the development, the developing roll rotation direction switching device 51 instructs the developing roll drive motor 52 to rotate the developing roll 32 in the predetermined direction A. And the developing roll 3
2 starts rotating in the predetermined direction A, the developing roll 32
The regulating blade 111 is disposed in contact with the developing roll 3.
It moves in the same direction (A direction) as the rotation direction of No. 2 and contacts and is regulated by the blade holding frame 112 and is held at the layer thickness regulating position P1. At this time, an elastic layer 113 is provided on the inner surface of the concave portion of the blade holding frame 112, and the pressing force of the elastic layer 113 can move with the rotation of the developing roll 32 by the regulating blade 111, and regulates the developer layer thickness. The pressure is set to such an extent that a sufficient pressing force can be obtained (2 to 10 g / cm).
Therefore, in the developing operation process, the developer regulating member 11
Thereby, the layer thickness of the developer is regulated to be appropriate.

Immediately after the completion of the development (at the time of non-development), an instruction is issued from the development roll rotation direction switching device 51 to the development roll drive motor 52 to rotate the development roll 32 in the reverse direction B of the predetermined direction. When the developing roll 32 starts rotating in the reverse direction B of the predetermined direction, the regulating blade 111, which is arranged in contact with the developing roll 32, moves in the same direction (B direction) as the rotating direction of the developing roll 32, and The blade is held in the standby position P2 while being in contact with and regulated by the blade holding frame 112 in the direction opposite to the time. And the regulating blade 1
The developing roll rotation direction switching device 51 controls the developing roll drive motor 52 to stop the rotation of the developing roll 32 around the time when the blade 11 contacts and is regulated by the blade holding frame 112.
Therefore, after the development is completed, the developer remaining in the nip portion between the developer regulating member 11 and the developing roll 32 is returned.

Here, in the present embodiment and the comparative embodiment (in which a fixed type layer thickness regulating blade is used), A
(4) Running test of 10,000 sheets in horizontal feed (test conditions are low temperature and low humidity (10 ° C, 10%) and high temperature and high humidity (30 ° C, 90%)
Under the two conditions). As a result, as shown in FIG. 4, in the comparative example, formation of streaks was observed on the recording paper on about 5,000 sheets under low temperature and low humidity, and on about 3,000 sheets under high temperature and high humidity. However, in the present embodiment, even when a running test was performed on up to 10,000 sheets, no generation of streaks on the recording paper was observed.

Embodiment 2 This embodiment is substantially the same as Embodiment 1 except that FIG.
As shown in FIG.
12. That is, in the present embodiment,
The blade holding frame 112 is made of an elastic material such as a leaf spring, and is formed of a channel-shaped cross section having substantially the same shape as that of the first embodiment.
2a is configured as an inclined piece which is inclined so that the gap between the developing roller 32 and the developing roller 32 in the rotation direction A gradually becomes narrower. The side functions as a layer thickness regulating position P1 with which the side abuts. The regulating blade 111 is made of, for example, a stainless steel plate. At the layer thickness regulation position P1, selection is made so that pressure is applied by elastically contacting the frame piece (inclined piece) 112a of the blade holding frame 112.

Thus, as in the first embodiment, when the development is started, the regulating blade 111
With the rotation of the developing roller 32, the developing roller 32 moves in the same direction as the predetermined rotation direction A, enters the gap between the frame 112a of the blade holding frame 112 and the developing roller 32, and moves to the layer thickness regulating position P1.
Is held. At this time, the regulating blade 111 is provided with the inclination angle and elasticity of the blade holding frame 112 and the developing roll 3.
2, a pressing force determined from the rotation speed, the thickness of the regulating blade 111, and the like is applied. After the development is completed, the regulating blade 1 is rotated by the reverse rotation of the developing roll 32.
11 is a frame piece 1 which is a wall on the opposite side of the blade holding frame 112.
12b, and is held at the standby position P2. At this time, the regulating blade 111 is
12 does not enter the gap between the frame piece 112b and the developing roll 32. In the present embodiment, the shape of the regulating blade is substantially flat, but is not limited to this.
For example, as shown in FIG.
The inclined portion 111a is provided so as to be substantially engaged with the shape of the blade holding frame 112 so as to be easily held in
A curved surface portion 111b may be provided as shown in FIG. In the present embodiment, as in the first embodiment, a running test was performed on 10,000 sheets of A4 size transverse feed.
No running streak was found on the recording paper even when a running test was performed on up to 000 sheets.

Third Embodiment This embodiment is substantially the same as the first embodiment, but is different from the first embodiment in that, as shown in FIG. The contact member is regulated by the blade 11
1 is replaced with a cylindrical regulating roll 114, and the regulating roll 114 is movably disposed in a roll holding frame 115 (in this example, a configuration similar to the blade holding frame 112 of the first embodiment). In the present embodiment, the regulation roll 114 is made of, for example, a metal such as a SUS plate or the like having a toner charging performance, plastic, or a metal provided with a coat layer on a metal surface. Is the elastic layer 113 on the bottom surface of the concave portion similar to the first embodiment.
The outer diameter of the regulating roll 114 is appropriately selected to be larger than the gap between the elastic layer 113 of the roll holding frame 115 and the developing roll 32, and the elastic layer 113 is pressed against the developing roll 32 by elastic force. It is arranged to be pressed.

Thus, similarly to the first embodiment, when the development is started, the regulation roll 114 moves in the same direction as the predetermined rotation direction of the development roll 32 with the rotation of the development roll 32, and the roll holding frame is moved. The frame 115 abuts on one end side 115a and is held at the layer thickness regulating position P1 by the frame piece 115a. At this time, a pressing force necessary for regulating the layer thickness of the developer is applied to the regulation roll 114 from the elastic layer 113 of the roll holding frame 115. After the development is completed, the regulating roll 114 moves until it comes into contact with the frame piece 115b, which is the wall on the opposite side of the roll holding frame 115, with the reverse rotation of the developing roll 32, and the standby position P by the frame piece 115b.
2 is held. Also in the present embodiment, as in the first embodiment, a running test was performed on 10,000 sheets of A4 size transverse feed. As a result, no streak was formed on the recording paper even when the running test was performed up to 10,000 sheets. Was.

[0035]

As described above, according to the developing device of the present invention, the developer layer thickness regulating member is provided with the contact member movable between the layer thickness regulating position and the standby position,
The contact member is held at the layer thickness regulating position during development, and the contact member is moved to the standby position during non-development. Therefore, while effectively regulating the layer thickness of the developer, the developer carrier and the developer layer thickness regulation are effectively performed. The one-component developer staying in the vicinity of the contact portion with the member or the one-component developer attached to the contact member can be peeled off. For this reason, in addition to keeping the developer layer thickness regulating performance good, the one-component developer stagnation near the contact portion between the developer carrier and the developer layer thickness regulating member and the developer layer thickness regulating member It is possible to eliminate the occurrence of fogging and streaks on an output image caused by the adhesion of the one-component developer to the output image, and to obtain a good image over a long period of time. Further, according to the present invention, since the contact member moves with the rotation of the developer carrier, between the time of contact and the time of non-contact, the contact member moves between the developer carrier and the developer layer thickness regulating member. The relative positional relationship between the two at the contact portion (nip portion) changes, and it is possible to avoid a situation where the pressing force always acts on the nip portion of the contact member during development. For this reason, permanent deformation of the developer layer thickness regulating member (contact member) which occurs with time can be reduced, and the life of the developer layer thickness regulating member can be extended.
In particular, a predetermined pressing force is applied to the contact portion between the developer carrier and the developer layer thickness regulating member at the time of development, and the contact member is moved during standby so that the pressing force is hardly applied. A load is not applied to the nip portion of the developer layer thickness regulating member at the time of development during standby, and as a result, permanent distortion of the developer layer thickness regulating member that occurs with time can be more reliably reduced. Further, according to the present invention, since the contact member can be configured without being fixedly adhered, the thickness of the one-component developer can be stably regulated without causing uneven adhesion. Furthermore, according to the developer layer thickness regulating member of the present invention, the above-described various effects can be easily implemented by incorporating the developer layer thickness into the developing device.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory diagrams illustrating the configuration of the present invention.

FIG. 2 is an explanatory diagram of the one-component developing device according to the first embodiment.

FIGS. 3A and 3B are explanatory views showing the operation of a developer regulating member according to FIG. 3;

FIG. 4 is a graph showing a comparison between the developing device according to the first embodiment and a comparative example.

FIGS. 5A and 5B are explanatory views showing the operation of a developer regulating member according to Embodiment 2. FIGS.

FIGS. 6A and 6B are explanatory views showing a modification of the regulating blade according to the second embodiment.

FIGS. 7A and 7B are explanatory diagrams illustrating the operation of a developer regulating member according to Embodiment 3. FIGS.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Developer layer thickness regulating member, 1a ... Contact member, 1b ... Contact member movement regulating member, 2 ... Developer carrier, 3 ... Developer carrier driving means, 11 ... Developer regulating member, 21 ... Photoconductor drum , 32: developing roll, 34: developer peeling supply roll,
41: developing bias power supply, 51: developing roll rotation direction switching device, 52: developing roll drive motor, 111: regulating blade, 112: blade holding frame, 113: elastic layer, 1
14: regulation roll, 115: roll holding frame, A: predetermined rotation direction of developer carrier, B: reverse direction of predetermined rotation direction of developer carrier, T: one-component (non-magnetic) developer, P1 …
Layer thickness regulation position, P2 ... standby position

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Teruaki Koizumi 2274 Hongo, Ebina-shi, Kanagawa Fuji Xerox Co., Ltd. (72) Inventor Yuzo Ichikawa 2274 Hongo, Ebina-shi, Kanagawa Fuji Xerox Co., Ltd.

Claims (2)

[Claims] 1. A developer layer thickness regulating member that is disposed in pressure contact with a rotatable developer carrier and regulates the layer thickness of a one-component developer formed on the developer carrier. The developer layer thickness regulating member includes a contact member disposed at least in contact with the developer carrier and movably along a rotation direction of the developer carrier, and a moving range of the contact member. A contact member movement restricting member that regulates between the thickness regulating position and the standby position and presses the contact member against the developer carrier at least at the layer thickness regulating position. 2. The developing device comprising the developer layer thickness regulating member according to claim 1, wherein the developer carrier is disposed so as to be rotatable in both forward and reverse directions. A developing device characterized in that the developer carrier is driven and controlled by a developer carrier driving means to rotate in a forward direction during development and in a reverse direction during non-development after development is completed.