JPH052322A - Developing device - Google Patents

Abstract

PURPOSE:To surely prevent a developer from leakage from a gap between a regulating member for regulating the layer thickness of developer on a developer carrier and a sealing member for preventing the developer from leakage to an outside from the end of a developer carrier. CONSTITUTION:The leakage of the developer from a gap formed between a developer container and a developing sleeve is prevented by the sealing member 7. The sealing member 7 is constituted of a circular arc shaped member which is extended along the circumferential direction of the developing sleeve. A step part 7a is provided on the inner surface of the sealing member 7. The corner part of the blade for regulating the layer thickness of the toner on the developing sleeve is used in a step part 7a.

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 and a laser printer.

[0002]

2. Description of the Related Art Conventionally, a developing device used in an image forming apparatus such as an electrophotographic copying machine contains a one-component developer (hereinafter referred to as "toner") 1 as shown in FIGS. A developer container 2 is provided. The developer container 2 has an opening 2a.

A developing sleeve 3 for carrying the toner 1 while carrying it is rotatably incorporated in the developer container 2. A part of the outer peripheral surface of the developing sleeve 3 has an opening 2a.
It is arranged in the developer container 2 so as to project to the outside.

A blade 4 is attached to the developer container 2 to regulate the toner 1 carried on the developing sleeve 3 to a predetermined layer thickness and to frictionally charge the toner 1. The blade 4 is made of a strip-shaped elastic member extending along the longitudinal direction of the developing sleeve 3. The blade 4 is arranged above the developing sleeve 3 so that one edge thereof contacts the outer peripheral surface of the developing sleeve 3. The blade 4 is elastically deformed in the direction opposite to the rotation direction of the developing sleeve 3.

A squishy sheet 5 is attached to the developer container 2, and the squishy sheet 5 prevents the toner 1 from leaking to the outside through a gap formed between the outer peripheral surface of the developing sleeve 3 and the developer container 2. The squi sheet 5 is made of a strip-shaped elastic member extending along the longitudinal direction of the developing sleeve 3. The squi sheet 5 is arranged below the developing sleeve 3 so that one edge thereof contacts the outer peripheral surface of the developing sleeve 3. The squi sheet 5 is elastically deformed in the rotation direction of the developing sleeve 3.

Two seal members 6 are attached to the developer container 2. Each seal member 6 is a developing sleeve 3
It is made of an arc-shaped felt material extending along the circumferential direction. The one seal member 6 covers a gap formed between one end of the developing sleeve 3 and the developer container 3, and an inner peripheral surface of the seal member 6 and an outer peripheral surface of the end of the developing sleeve 3 are mutually predetermined. It is pressed by pressure. Further, the end portion of the one seal member 6 is superposed on the one edge portion of the blade 4 located on the one end side of the developing sleeve 3 from above.

Similar to the one seal member 6, the other seal member 6 covers the gap formed between the other end of the developing sleeve 3 and the developer container 3, and the inner peripheral surface thereof is used for developing. It is pressed against the outer peripheral surface of the other end of the sleeve 3 with a predetermined pressure. The other end of the seal member 6 is
It is superposed on the other edge of the blade 4 located on the other end side of the developing sleeve 3 from above.

[0008]

However, in the conventional developing device, one end of each seal member 6 is partially overlapped with the corresponding end of the blade 4, so that
Each seal member 6 becomes a portion facing the blade 4 and a portion facing the developing sleeve 3 by being deformed stepwise, so that between the portion facing the developing sleeve 3 and the end portion of the blade 4. May form a gap, and the toner 1 may leak from the gap to the outside.

In order to eliminate the above-mentioned gap, each seal member 6
It is possible to increase the degree of adhesion between the blade 4 and the seal member 6 by increasing the pressing force of the developing sleeve 3 against the developing sleeve 3. However, since the contact pressure between the blade 4 and the developing sleeve 3 increases, the melting of the toner 1 Adhesion occurs, and the toner 1 easily leaks from the portion where the toner 1 is fused. As a result, it is difficult to reliably prevent the toner 1 from leaking through the gap between the seal member 6 and the blade 4.

An object of the present invention is to provide a regulating member for regulating the layer thickness of the developer on the developer carrier and a seal member for preventing the developer from leaking from the end of the developer carrier to the outside. It is an object of the present invention to provide a developing device capable of reliably preventing the developer from leaking through the gap between the developing device and the developing device.

[0011]

According to the present invention, the above object is to provide a developer container containing a developer, a developer carrier for carrying the developer in the developer container, and A developer layer regulating member that regulates the friction of the developer carried on the developer carrying body to a predetermined layer thickness by friction with the developer carrying body, and frictionally charges the developer; Overlaid on the contact end with the developer carrier,
In a developing device comprising a seal member for preventing the developer from leaking to the outside through a gap between the developer carrier and the developer container, the seal member is a contact end of the developer layer regulating member. This is achieved by comprising an elastic member provided with a concave step for receiving the part.

[0012]

In the developing device of the present invention, the contact end of the developer layer regulating member with the developer carrying member and a part of the seal member are overlapped with each other, and a concave step provided in the seal member. The part receives the contact end of the developer layer restriction member. A gap for guiding the developer to the outside is not formed between the contact end of the developer layer regulating member and the seal member, and the developer is reliably prevented from leaking.
Further, it is not necessary to press the contact end portion of the developer layer regulating member with high pressure, and the fusion of the developer does not occur.

[0013]

Embodiments of the developing device of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the developing device of the present invention, FIG. 2 is an exploded perspective view showing the main part of the developing device of FIG. 1, and FIG. 3 is used for the developing device of FIG. 4 is a perspective view showing the sealing member, FIG. 4 is a view showing a state of the sealing member and the blade before the developing sleeve is assembled in the developer container, and FIG. 5 is a developing sleeve and the blade assembled in the developer container. It is a figure which shows the state relationship with a squishy sheet.

As shown in FIGS. 1 and 2, a developing device used in an image forming apparatus such as an electrophotographic copying machine is provided with a developer container 2 containing a toner. The developer container 2 has an opening 2a.

A developing sleeve 3 for carrying the toner while carrying the toner is rotatably incorporated in the developer container 2. The developing sleeve 3 is arranged in the developer container 2 so that a part of the outer peripheral surface thereof projects outward from the opening 2a. The developing sleeve 3 is made of a non-magnetic metal material such as aluminum or stainless steel.

A blade 4 is attached to the developer container 2 to regulate the toner carried on the developing sleeve 3 to a predetermined layer thickness and to frictionally charge the toner. The blade 4 is made of a belt-shaped member extending along the longitudinal direction of the developing sleeve 3, and the member is made of a rubber material, a synthetic resin such as PET, or an elastic material such as an elastic metal. The blade 4 is arranged above the developing sleeve 3 so that one edge thereof contacts the outer peripheral surface of the developing sleeve 3, and is elastically deformed in a direction opposite to the rotating direction of the developing sleeve 3.

A squi sheet 5 is attached to the developer container 2, and the squi sheet 5 prevents toner from leaking to the outside through a gap between the outer peripheral surface of the developing sleeve 3 and the developer container 2. The squi sheet 5 is made of a strip-shaped elastic member extending along the longitudinal direction of the developing sleeve 3. The squi sheet 5 is arranged below the developing sleeve 3 so that one edge thereof contacts the outer peripheral surface of the developing sleeve 3, and is elastically deformed in the direction opposite to the rotating direction of the developing sleeve 3.

Two seal members 7 are attached to the developer container 2. As shown in FIGS. 1 and 3, each seal member 7 is formed of an arc-shaped member extending along the circumferential direction of the developing sleeve 3, and the arc-shaped member is a foam material or a rubber material in which open cells are formed. Made of elastic material such as. On the inner peripheral surface of each seal member 7, a concave step portion 7a capable of receiving the corner portion of the blade 4 is formed.

The one seal member 7 covers a gap formed between one end of the developing sleeve 3 and the developer container 3, the inner peripheral surface of which is the outer peripheral surface of the one end of the developing sleeve 3. Are abutted against each other with a predetermined pressure. Further, as shown in FIG. 5, one seal member 7 has a step 7a.
The blade 4 located on one end side of the developing sleeve 3
Since one corner portion of the blade 4 is compressed in the thickness direction by being superposed on the blade 4 so as to receive one corner portion of the blade 4, when one corner portion of the blade 4 is compressed and deformed. The outer shape is the step portion 7 of the one seal member 7.
a and the developing sleeve 3 opposed thereto are matched with a space shape defined by the seal member 7 and the blade 4
One of the corners is in close contact with each other. Before compression deformation, that is, before the developing sleeve 3 is incorporated in the seal member 7, as shown in FIG. 4, the seal member 7 and the corner portion of the blade 4 have a deformation allowance interval with respect to the corner portion of the blade 4. It is arranged.

Like the one seal member 6, the other seal member 6 covers the gap formed between the other end of the developing sleeve 3 and the developer container 3, and the inner peripheral surface thereof is used for development. The outer peripheral surface of the other end of the sleeve 3 is butted with a predetermined pressure. In addition, one seal member 7 is
The step portion 7a is superposed on the blade 4 so as to receive one corner portion of the blade 4 located on the other end side of the developing sleeve 3, and one corner portion of the blade 4 is compressed in the thickness direction. There is. The outer shape of one corner of the blade 4 at the time of compressive deformation is matched with the space shape defined between the stepped portion 7a of the other seal member 7 and the outer peripheral surface of the developing sleeve 3 opposed to the stepped portion 7a. The seal member 7 and one corner portion of the blade 4 corresponding thereto are brought into close contact with each other.

Therefore, no gap is formed between each seal member 7 and the corresponding corner portion of the blade 4, and the toner is discharged from between the seal member 7 and the corresponding corner portion of the blade 4 to the outside. It never leaks.

Next, another seal member used in the developing device will be described. FIG. 6 is a perspective view showing another seal member used in the developing device of the present invention, and FIG. 7 is a perspective view showing yet another seal member used in the developing device of the present invention.
FIG. 8 is a perspective view showing still another seal member used in the developing device of the present invention.

Another seal member 8 used in the developing device
Is an arc-shaped base 9 and the base 9 as shown in FIG.
It has a two-layer structure having an arcuate contact portion 10 attached to the inner surface of the. The contact portion 10 has a rectangular notch 10
a is provided, and the notch 10a defines a concave step portion between the base portion 9 and the abutting portion 10 for receiving an end portion of a blade (not shown).

Therefore, when a material such as a felt material having a small degree of freedom in the processed shape is used for the seal member, the stepped portion having a shape corresponding to the blade shape can be easily formed by using the two-layer structure. .

As shown in FIG. 7, still another seal member 11 has a two-layer structure having an arcuate base portion 12 and an arcuate contact portion 13 attached to the inner surface of the base portion 12. The contact portion 13 is formed with a notch 13a for defining a step portion that receives the end portion of the blade. The base 12 is made of a flexible material having a small compression set, such as foam.

On the other hand, the contact portion 13 is made of Teflon felt material having excellent slidability. Therefore, the materials of the base portion 12 and the contact portion 13 can be selected according to the application, and the sealing performance can be improved and the life can be extended.

As shown in FIG. 8, a step portion 14a for receiving the end portion of the blade and a step portion 14b for receiving the squishe sheet can be formed on still another seal member 14.

[0029]

As described above, according to the developing device of the present invention, since it is received in the concave step portion provided in the seal member, the contact end portion of the developer layer regulating member. A gap for guiding the developer to the outside is not formed between the seal member and the seal member, and it is possible to reliably prevent the developer from leaking from the gap.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a developing device of the present invention.

FIG. 2 is an exploded perspective view of a main part of the developing device of FIG.

FIG. 3 is a perspective view showing a seal member used in the developing device of FIG.

FIG. 4 is a diagram showing a state of a seal member and a blade before a developing sleeve is incorporated in a developer container.

FIG. 5 is a diagram showing a state relationship among a developing sleeve, a seal member, a blade, and a squishy sheet which are incorporated in a developer container.

FIG. 6 is a perspective view showing another seal member used in the developing device of the present invention.

FIG. 7 is a perspective view showing still another seal member used in the developing device of the present invention.

FIG. 8 is a perspective view showing still another seal member used in the developing device of the present invention.

FIG. 9 is a configuration diagram showing a conventional developing device.

10 is a diagram showing a state relationship among a developing sleeve, a seal member, a blade, and a squishy sheet of the developing device of FIG.

[Explanation of symbols]

2 developer container 3 Development sleeve 4 Blade (developer layer control member) 5 Squishy sheet 7,8,11,14 Seal member 9,12 base 10, 13 abutment part 7a, 14a, 14b Step portion 10a, 13a Notches

Claims (5)

[Claims] 1. A developer container for containing a developer, a developer carrier for carrying the developer in the developer container, and a developer carrier by contacting the developer carrier. A developer layer regulating member that regulates the friction of the developer carried to a predetermined layer thickness and frictionally charges it, and a part thereof is superposed on the contact end of the developer layer regulating member with the developer carrying member, In a developing device including a seal member for preventing the developer from leaking to the outside through a gap between a developer carrier and the developer container, the seal member is a contact end portion of the developer layer regulating member. A developing device comprising an elastic member provided with a concave stepped portion for receiving the toner. 2. The contact end of the developer layer regulating member with the developer carrying member is compressed and deformed between the developer carrying member and the seal member, and the outer shape due to the compressive deformation of the contact end is the above. The developing device according to claim 1, wherein the developing device matches the shape of the step portion. 3. The seal member has a two-layer structure having a base portion and an abutting portion which is superposed on the base portion and which has a contact surface with a developer carrying member. The developing device described. 4. The developing device according to claim 3, wherein the material of the base portion and the material of the contact portion forming the two-layer structure of the seal member are different from each other. 5. A squeeze sheet for preventing the developer from leaking to the outside through a gap between the developer container and the developer carrying member, and a seal member having a concave step portion for receiving the squishe sheet. The developing device according to claim 1.