JP2004170699A - Developing device, process cartridge and image forming apparatus equipped with the developing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing device having no danger of developer leakage out of a fitting surface by improving the sealing performance between the fitting surfaces of respective components representing the casing of the developing device in an electrophotographic process for a copying machine, a facsimile machine, and a printer, etc., and to provide a process cartridge and an image forming apparatus equipped with the developing device. <P>SOLUTION: In order to prevent the leakage of the developer 5, a space 2 for packing and storing semi-solid matter is formed in the fitting part A where the casing 1 and the counter component 3 are fitted and assembled with each other. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a developing device in an electrophotographic process such as a copying machine, a facsimile, a printer, and the like, a process cartridge having the developing device, and an image forming apparatus.
[0002]
[Prior art]
Developers and toners used in recent developing devices have been reduced in particle size to several μm to improve image quality. However, it is becoming difficult to prevent the developer from leaking only by screwing.
In order to cope with such a situation, the sealing property is secured by improving the accuracy of the fitting surface, making full use of sealing parts and the like, and further performing screwing and the like. However, there is a limit to the surface accuracy of the casing, and it is extremely time-consuming, for example, by individually correcting the accuracy.
[0003]
[Problems to be solved by the invention]
In the electrophotographic process of a copier, a facsimile, a printer, or the like, the leakage of the developer in the casing fitting portion is made by fitting the precision of the casing to the precision of the mating part to be fitted. There is a limit to the accuracy, and it takes a lot of time to individually correct the accuracy.
For example, when the process of manufacturing parts is performed in a large number of pieces, it takes time to prepare the production to adjust the accuracy. Further, even if the accuracy is once obtained, the dimensions and warpage accuracy of the component may vary within the tolerance during molding, and the developer may leak due to the degree of variation.
Therefore, an object of the present invention is to solve the above-mentioned problems by increasing the sealing performance of individual component fitting surfaces representing the casing of a developing device in an electrophotographic process such as a copying machine, a facsimile, a printer, and the like. An object of the present invention is to provide a developing device which does not cause developer leakage from the surface, a process cartridge including the developing device, and an image forming apparatus.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention according to claim 1, a semi-solid substance is filled in a fitting portion between a casing and a mating part to be fitted and assembled into the casing in order to prevent developer leakage. The most important feature is a developing device having a space for storing.
According to a second aspect of the present invention, the developing device according to the first aspect has a space on the casing side for filling and storing a semi-solid substance.
According to the third aspect of the present invention, a main feature of the developing device according to the first or second aspect is that a confirmation space for confirming protrusion of the filled semi-solid substance is provided between the casing and the counterpart component. I do.
According to a fourth aspect of the present invention, the developing device according to the first or second aspect is characterized in that the space for storing the semi-solid substance in the fitting portion is filled with a lubricant.
The invention according to claim 5 is characterized in that, in the casing and the space, a contact portion at a tip end of an ejector pin used for an injection mold for the casing and a nesting step are provided. In other words, the mold is configured such that the tip of the ejector pin is located at a position corresponding to the space within the molded product, and the boundary between the nest and the mold body is located at a position corresponding to the space within the space. The mold is configured as follows.
According to a sixth aspect of the invention, a process cartridge having the developing device according to any one of the first to fifth aspects is a main feature.
According to a seventh aspect of the present invention, an image forming apparatus equipped with the developing device according to any one of the first to fifth aspects is a main feature.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing an embodiment of a developing device according to the present invention as a configuration in which a space is provided on a casing-side fitting surface. In FIG. 1, a groove-shaped space 2 for filling and storing a semi-solid substance is provided in a fitting portion A at an upper portion of a casing 1.
FIG. 2 is a top view showing a state in which a mating component is fitted in a space 2 provided in a fitting portion A at an upper portion of the casing 1. The mating part 3 is fitted into the fitting part A. In this embodiment, the fitting portion A is located at the upper part of the casing 1 and the space 2 is provided on the inner wall of the casing 1. However, a similar groove-shaped space 2 is formed on the corresponding peripheral wall of the mating part 3 to be fitted. It is also possible to provide.
When the semi-solid substance is filled from one opening of the space 2 after the mating component 3 is fitted in the space A, the semi-solid substance is used as a confirmation space for confirming the overflow of the filled semi-solid substance. Comes out of hole 4.
When the semi-solid material comes out of the hole 4 on the opposite side, by completing the filling, the space 2 is filled with the semi-solid material, and the leakage of the developer 5 inside the casing from the fitting surface is prevented. can do.
[0006]
Further, by providing the space 1 in the casing 1 or the mating part 3 of the present invention, it is possible to increase the degree of freedom in designing a mold when injection molding these parts. That is, the mold is provided with an ejector pin for projecting the molded product or a nest is provided.In the case of the ejector pin, the tip of the pin comes into contact with the molded product at the time of ejection, so that the shape of the pin tip is formed on the molded product. There is a defect that is transferred. In the present invention, by designing the mold so that the tip of the pin abuts in the space 2, the protrusion after the protrusion is not transferred to an important part of the molded product. In addition, by setting the step in the case where the nest is used in the space 2, it is possible to prevent the nest step from being transferred to the main part of the molded product. By providing the ejector pin contact portion and the nesting step inside the shape of the space 2 as described above, it is not necessary to perform fine adjustment such as the size of the step.
In other words, the mold is configured such that the tip of the ejector pin is located at a position corresponding to the space within the molded product, and the boundary between the nest and the mold body is located at a position corresponding to the space within the space. The mold is configured as follows.
[0007]
As the semi-solid substance to be filled in the space 2 in the fitting portion A, a lubricant (sealant, grease, or the like) is filled.
By providing a groove-shaped space 2 for filling a semi-solid substance on the fitting surface of either the casing 1 or the mating component 3 and filling the space 2 with the semi-solid substance, the surface accuracy of the casing 1 is affected. Without this, it is possible to prevent the developer from leaking from the fitting surface over time.
Further, by adopting a configuration in which a semi-solid substance is sealed in the space 2 provided in advance, even if a gap that causes leakage due to variation in the counterpart component 3 is generated, the semi-fixed substance penetrates (fills) and fills the gap. Since the filling is completed, it is possible to reliably prevent the developer from leaking from the fitting portion A. Therefore, it is possible to prevent the developer from leaking from the developing device in an electrophotographic process such as a copying machine, a facsimile, and a printer.
The developing device of the present invention can be applied to a developing device alone, but can also be applied to a developing device included in a process cartridge in which the developing device is integrated with other peripheral components.
Further, a developing device having the above configuration or an image forming device having the process cartridge is also included in the technical scope of the present invention.
[0008]
【The invention's effect】
As described above, according to the first aspect, the filler can be easily injected into the space between the casing and the mating component to be fitted.
According to the second aspect, it is possible to widen the dimensional tolerance of the casing in which it is difficult to obtain accuracy.
According to the third aspect, it can be easily confirmed that the filling material has been reliably sealed in the space to be filled.
According to the fourth aspect, since the space for storing the semi-solid substance in the fitting portion is filled with the lubricant, it is possible to reliably prevent the developer from leaking.
According to the fifth aspect, since the nesting step and the ejector pins are formed in the casing and the space, it is possible to improve the margin of the mold accuracy of the parts.
According to the sixth aspect, it is possible to provide a process cartridge equipped with a developing device in which developer leakage does not occur.
According to the seventh aspect, it is possible to provide an image forming apparatus equipped with a developing device in which developer leakage does not occur.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an embodiment of a developing device according to the present invention as a configuration in which a space is provided on a casing-side fitting surface.
FIG. 2 is a top view showing a state where a mating component is fitted in a space provided in a fitting portion at an upper portion of a casing.
[Explanation of symbols]
1 Casing 2 Space 3 Mating part 4 Hole on opposite side (confirmation space)
5 Developer

Claims (7)

In a developing device having a casing having a fitting portion and a mating part fitted and assembled to the fitting portion of the casing, in order to prevent developer leakage to the fitting portion or the mating part, A developing device having a space for filling and storing a semi-solid substance. The developing device according to claim 1, further comprising a space on the casing side for filling and storing a semi-solid substance. The developing device according to claim 1, wherein a confirmation space for confirming protrusion of the filled semi-solid substance is provided between the casing and the counterpart component. 3. The developing device according to claim 1, wherein the space for storing the semi-solid substance in the fitting portion is filled with a lubricant. 3. The developing device according to claim 1, wherein a contact portion at an end of an ejector pin used for a mold for injection molding of the casing and a nesting step are provided in the casing and the space. A process cartridge comprising the developing device according to claim 1. An image forming apparatus comprising the developing device according to claim 1.

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