JP2002072676A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely perform sealing without exerting adverse influence even when a regulating member is pressed to a developing roller with fixed load. SOLUTION: In this developing device, the developing roller 4 and a regulating member 1 forming a toner thin layer by regulating toner amount while pressing its edge to the roller 4 are disposed in a housing 2, and an electrostatic latent image formed on an image carrier is made visualizable as a toner image. In the device, a seal member 9 bent at an angle parallel to the surface of a supporting part 3 on a developing chamber side from the rear surface of the member 1 is stuck to the rear surface of the member 1 and arranged to seal a gap between the rear surface of the member 1 and the supporting part 3. By bending the seal member at an angle parallel to a direction where the load is exerted on the member 1, force is hardly applied in a direction where the movement of the member 1 is hindered, and the gap of the developing chamber formed on the rear surface of the member 1 is sealed while keeping the smooth movement of the member 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image bearing member having a developing roller and a regulating member which presses the leading end of the developing roller to regulate the amount of toner to form a thin film of toner. The present invention relates to a developing device for visualizing an electrostatic latent image formed on a toner image into a toner image.

[0002]

2. Description of the Related Art In an image forming apparatus using an electrophotographic method,
A latent image forming device forms an electrostatic latent image on an image carrier such as a photoreceptor that is driven to rotate, and the toner conveyed by a developing device is applied to develop the electrostatic latent image to form a visible image as a toner image. Become In this case, the developing device is required to stably form a uniform thin film of the toner on the developing roller that transports the toner, and for this purpose, a member (a regulating member, a regulating blade) that regulates the toner amount is used. The present applicant has proposed a developing device that can easily adjust the height and skew of the regulating member and press the developing member with a constant spring load (see, for example, Japanese Patent Application No. 11-266404).
The outline is described below.

FIG. 4 is a view for explaining the outline of a developing device which has been proposed. Reference numeral 1 denotes a regulating member, 2 denotes a housing, 3 denotes a blade supporting member, 4 denotes a developing roller, 5 denotes a supporting portion, and 6 denotes a skew. An adjusting unit, 7 is a blade pressing spring, and 8 is a blade pressing spring.

In the developing device shown in FIG. 4, the developing roller 4 is supported on the housing 2 and the regulating member 1 is mounted on the upper surface, and the ridge line a at the tip thereof is pressed against the developing roller 4, and the opposite side of the ridge line a is fixed. It is supported by two support portions 5. The blade supporting member 3 is provided so as to support the regulating member 1 on its back surface. The supporting portion 5 has two protrusions between the back surface of the regulating member 1 and the upper surface of the blade supporting member 3. Contact and support in the height direction. The blade pressing spring portion 7 has a plurality of, for example, five blade pressing springs 8 disposed therein for causing the developing roller 4 to press the ridge line a at the tip of the regulating member 1, and is shown in a sectional view of FIG. As shown, a blade pressing spring 8 is stretched between the spring mounting hook of the regulating member 1 and the spring mounting hook of the blade supporting member 3. The skew adjustment unit 6 provides two long holes near both ends of the support line parallel to the ridgeline at the tip of the regulating member 1 and also provides pins at positions of the blade support member 3 corresponding to the two long holes, Each pin fits in the two long holes to support the regulating member 1 freely in the longitudinal direction, and adjusts the skew, that is, the skew in the left-right direction in the figure using the eccentric cam.

One of the two supporting portions 5 supporting the regulating member 1 supports a projection provided on the blade supporting member 3 at a predetermined height by contacting the projection provided on the blade supporting member 3 with the back surface of the regulating member 1. On the other hand, the mounting height (Y) of the regulating member 1 is adjusted by supporting the tip of a screw whose height is adjustable by screwing the regulating member 1 into contact with the blade supporting member 3. On the other hand, the skew (X) adjustment is performed by fitting the skew adjustment eccentric cam into one of the long holes in the skew adjustment unit 6. By these adjustments, the regulating member 1 is adjusted so that there is no left-right difference in the interference force with the regulating member 1 and that the regulating member 1 and the developing roller 4 are parallel without any twist between the ridgeline at the tip of the regulating member 1 and the developing roller 4. Can be supported.

[0006]

As described above, the regulating member is configured to press the developing roller with a constant load in order to stably form a thin film of toner on the developing roller. A small gap is formed in the portion and the support portion of the regulating member, so that the toner is easily leaked. Therefore, conventionally, for example, as a seal between the regulating member 1 and the blade supporting member 3, a buffer member such as sponge is interposed therebetween, or a sheet such as PET is attached to the blade supporting member 3 to form the regulating member 1. The configuration is such that it is applied to the base.

However, in the above-described conventional configuration, since the sealing member receives a reaction force from the blade supporting member to the regulating member, there is an adverse effect when the regulating member is pressed against the developing roller with a constant load. Would.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is intended to ensure that a sealing can be performed without adversely affecting a developing roller even when a regulating member presses a developing roller with a constant load. Is what you do.

For this purpose, the present invention provides a developing roller and a regulating member which regulates the amount of toner by pressing the tip of the developing roller to form a thin film of toner in a housing, thereby forming the developing roller on an image carrier. In the developing device for visualizing the electrostatic latent image thus formed into a toner image, a sealing member bent from the back surface of the regulating member to an angle parallel to the surface of the supporting portion on the developing chamber side is provided on the back surface of the regulating member. Affixed, arranged so as to seal the gap between the back surface of the regulating member and the support portion, wherein the sealing member is a PET film,
The surface of the support portion is parallel to a direction in which a load is applied to the regulating member.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view illustrating an embodiment of the developing device according to the present invention, and FIG. 2 is a top view illustrating the embodiment of the developing device according to the present invention. Regulating member, 2 housing, 3 blade supporting member, 4 developing roller, 5 supporting portion, 6 skew adjusting portion, 7 blade pressing spring portion, 8 blade pressing spring, 9, 10a and 10b sealing members Is shown.

In FIG. 1 and FIG. 2, the developing roller 4
The regulating member 1 is mounted on the upper surface of the housing 2, and the regulating member 1 is attached to the upper surface, and the ridge at the tip thereof is pressed against the developing roller 4. The regulating member 1 supports the blade supporting member 3 on the side opposite to the ridge. The blade supporting member 3 is provided so as to support the regulating member 1 on its back surface.
The two protrusions are brought into contact between the back surface of the blade support member 3 and the upper surface of the blade support member 3 to support the height direction. The blade pressing spring portion 7 includes a plurality of, for example, five blade pressing springs 8 provided inside the developing roller 4 to press the ridgeline at the tip of the regulating member 1. A blade pressing spring 8 is stretched between the blade supporting member 3 and a spring mounting hook.

The seal member 9 seals a gap between the back surface of the regulating member 1 and the blade supporting member 3 and prevents the toner from being caught in the gap, thereby adversely affecting the load of the regulating member 1 pressing against the developing roller 4. To prevent, for example, PE
As shown in the figure, a T film is adhered to the back surface of the regulating member 1 to seal a gap at a contact portion with the blade supporting member 3. The seal member 9 is bent from the back surface of the regulating member 1 to an angle parallel to the surface of the blade supporting member 3 on the developing chamber side, and the surface of the blade supporting member 3 is a direction in which a load is applied to the regulating member 1. Is parallel to Therefore,
Almost no force is applied in the direction in which the movement of the regulating member 1 pressing the developing roller 4 is obstructed, and the gap between the back surface of the regulating member 1 and the blade support member 3 is sealed while maintaining the smooth movement of the regulating member 1. can do.

The sealing members 10a and 10b are made of urethane sheets and are arranged in a doubly spaced position and at an angle downstream of the developing roller 4 to reduce the load on the developing roller 4 so that filming is achieved. Etc. are suppressed. In addition, by forming each seal member at an angle to a certain extent, even when the housing is warped or impacted, it hits the developing roller at a different angle, thereby achieving an effective seal.

FIG. 4 is a diagram showing an example of a configuration using a developing device according to the present invention in a full-color image forming apparatus.
1 is a photoreceptor, 32Y, 32C, 32M and 32K are developing devices, 33 is a housing, 34 developing roller, 35 is a regulating member, 36 is a blade supporting member, 37 is a blade pressing spring, 38 is a developing cover, and 39 is a stirring shaft. , 40 indicate a toner cartridge.

As shown in FIG. 4, as a full-color image forming apparatus equipped with the developing device according to the present invention, a yellow Y for developing an electrostatic latent image around a photosensitive member 31 along the rotation direction thereof is provided. , A developing unit 32 composed of developing units for four colors of C for cyan, M for magenta and K for black
Y, 32C, 32M, and 32K are arranged. A charging roller as a charging unit; an exposure unit for forming an electrostatic latent image on the photoconductor 31; an intermediate transfer device for transferring a toner image formed on the photoconductor 31 onto an intermediate transfer belt; Although a photoconductor cleaning device for removing the toner remaining on the body 31 is arranged, these are already well-known configurations in the color image forming apparatus and are not directly related to the present invention. Is omitted.

The operation of the full-color image forming apparatus will be briefly described. The photoconductor 31 has a thin cylindrical conductive substrate and a photosensitive layer formed on the surface thereof, and is driven to rotate by driving means (not shown). Developing unit 32Y,
32C, 32M, and 32K are provided so as to be swingable with respect to the photoconductor 31, so that only one developing roller of one developing unit can selectively contact the photoconductor 31 for each rotation of the photoconductor 31. Have been. When an image is formed, for example, when an image forming signal is input from a computer (not shown), the photosensitive member 31, the developing rollers of the developing unit 32 and the intermediate transfer belt are driven to rotate.

First, the outer peripheral surface of the photoreceptor 31 is uniformly charged by a charging roller, and the outer peripheral surface is selectively exposed by an exposure unit according to image information of a first color (for example, yellow). Is formed. At this time, only the developing roller of the yellow developing device comes into contact with the photoconductor 31, whereby a yellow electrostatic latent image toner image is formed on the photoconductor 31. This toner image is transferred onto an intermediate transfer belt to which a primary transfer voltage having a polarity opposite to the charging polarity of the toner is applied, and the toner remaining on the photoconductor 31 is removed by a photoconductor cleaning device. The outer peripheral surface of the body 31 is discharged by the discharging means.

The above operation corresponds to the second, third, and fourth colors of the image forming signal, and the latent image formation and development by one rotation of the photosensitive member 31 and the intermediate transfer belt are repeated. Four color toner images corresponding to the content of the signal are superimposed and transferred on the intermediate transfer belt. And
This full-color image is transferred onto a recording medium.

When the developing device according to the present invention is used in a full-color image forming apparatus as described above, the blade pressing spring 3
Since the control device 7 is disposed below the regulating member 35, that is, in the developing chamber, the space of the developing device 32 can be reduced in the height direction, which is extremely effective particularly in miniaturizing a full-color device.

It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the above-described embodiment, the description has been given of a form applied to the developing device already proposed by the present applicant.However, the present invention relates to a developing device in which a regulating member is pressed against a developing roller with a constant load by a spring or the like. If a seal member is bent at an angle parallel to the direction in which the load is applied to the regulating member at a position where a gap is formed between the regulating member and the back surface of the developing chamber so that the toner is sandwiched between the regulating member and the back surface of the regulating member, Good. Therefore, it goes without saying that the present invention can be applied not only to a developing device mounted on a full-color image forming apparatus, but also to a developing device mounted on a mono-color or black-and-white image forming apparatus and a developing device mounted on another image forming apparatus.

[0021]

As is apparent from the above description, according to the present invention, the developing roller and the regulating member which presses the leading end of the developing roller into the housing to regulate the amount of toner and form a thin film of toner are provided. In a developing device for arranging and visualizing an electrostatic latent image formed on an image carrier into a toner image, the developing device is bent at an angle parallel to a surface of a supporting portion on a developing chamber side from a back surface of a regulating member. Paste the sealing member on the back of the regulating member,
Since the gap between the back surface of the regulating member and the support portion is arranged to be sealed, the sealing member is bent at an angle parallel to the direction in which the load is applied to the regulating member, thereby preventing movement of the regulating member. Can take very little force. Therefore, it is possible to seal the gap of the developing chamber formed on the back surface of the regulating member while maintaining the smooth movement of the regulating member.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining an embodiment of a developing device according to the present invention.

FIG. 2 is a top view for explaining an embodiment of the developing device according to the present invention.

FIG. 3 is a diagram illustrating a configuration example using a developing device according to the present invention in a full-color image forming apparatus.

FIG. 4 is a diagram for explaining an outline of a developing device already proposed.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 regulating member 2 housing 3 blade supporting member 4 developing roller 5 supporting portion 6 skew adjusting portion 7 blade pressing spring portion 8 blade pressing spring
9, 10a, 10b ... seal member

Claims (3)

[Claims] An electrostatic roller formed on an image bearing member is provided in a housing with a developing roller and a regulating member that presses a tip of the developing roller to regulate a toner amount to form a thin film of toner. In a developing device that visualizes a latent image into a toner image,
A sealing member bent from the back surface of the regulating member at an angle parallel to the surface of the supporting portion on the developing chamber side is attached to the back surface of the regulating member to seal a gap between the back surface of the regulating member and the supporting portion. A developing device, comprising: 2. The developing device according to claim 1, wherein said seal member is a PET film. 3. The developing device according to claim 1, wherein a surface of said support portion is parallel to a direction in which a load is applied to said regulating member.