JP2000081785A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device making the service life thereof possible to be easily and exactly judged. SOLUTION: In this developing device 1 equipped with a developing sleeve 4 facing opposite to an image carrier with a specified range, on respective periphery of butting rollers 5 and 6 disposed in order to maintain the above image carrier and the developing sleeve 4 with the specified range, respective groove (wear detecting means) 5a and 6a is provided thereon. In this case, since respective butting periphery on the butting roller 5 and 6 held in contact with the image carrier is gradually worn by the rotation thereof corresponding to the rotation of the image carrier, by confirming by the visual observation or measuring by a simple measuring tool with respect to the state of respective groove 5a and 6a formed on these butting periphery as wear detecting means, the developing sleeve 4 is made possible to easily and exactlly be predicted whether being used to the limit with no residual life, or possible to be used how long hereafter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device such as an electrophotographic recording device such as a copying machine and a printer.

[0002]

2. Description of the Related Art Various types of developing devices for developing an electrostatic latent image formed on an image carrier by an electrophotographic method or an electrostatic recording method have been proposed.
FIG. 9 shows a typical developing device.

FIG. 9 is a perspective view showing the appearance of a conventional developing device 101. In FIG. 9, reference numeral 102 denotes a developing container.
Inside thereof, a toner (not shown) is stored. Also, 1
Reference numeral 03 denotes a lid. The lid 103 has an opening 103a for supplying toner.

Reference numeral 104 denotes a developing sleeve, and both ends of the developing sleeve 104 are rotatably supported by the developing container 102. Reference numerals 105 and 106 denote abutting rollers, which are rotatably supported coaxially with the developing sleeve 104. Here, butting roller 10
The outer diameter of the developing sleeve 104 is set larger than the outer diameter of the developing sleeve 104. When the abutting rollers 105 and 106 abut on a photosensitive drum (not shown), a predetermined gap is provided between the photosensitive drum and the developing sleeve 104. Is formed. At this time, the abutting rollers 105 and 106 rotate together with the rotation of the photosensitive drum.

Reference numeral 107 denotes a drive input gear. The drive input gear 107 meshes with a drive gear (not shown) provided on the main body side to rotationally drive the developing sleeve 104.

The developing device 101 configured as described above develops the latent image formed on the photosensitive drum serving as an image carrier and visualizes it as a toner image.

[0007] Conventionally, a cartridge type developing device in which toner cannot be supplied is replaced with a new one when the toner runs out, and is discarded as it is.

On the other hand, the life of a developing device capable of supplying toner has been determined based on the state of an image, the number of sheets passed through the main body, or the number of times toner has been supplied.

[0009]

However, the above-described conventional method for determining the life of a developing device lacks accuracy. For example, in the judgment based on the image, it is difficult to distinguish it from the image deterioration caused by factors other than the developing device, and thus the accuracy is lacking.
In addition, the judgment based on the number of sheets passed through the main unit and the number of toner replenishments may be incorrect, considering that the developing device has been replaced before the end of its life for some reason. Lack.

[0010] Recently, it has been required to reuse parts and devices from the viewpoint of environmental problems and the like, and it has become necessary to disassemble machines that have returned from the market and reuse those that can be reused. Was. In this case, it is important to determine the remaining life of the component or the device.

In reusing the developing device, the conventional life judgment is not accurate, and there is a possibility that even a usable device may be discarded, which is inefficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a developing device capable of easily and accurately determining the life.

[0013]

According to a first aspect of the present invention, there is provided a developing apparatus including a developing sleeve which faces a predetermined distance from an image carrier.
A wear detecting means is provided on a peripheral surface of an abutting roller provided to keep the image carrier and the developing sleeve at a predetermined distance.

According to a second aspect of the present invention, in the first aspect, the wear detecting means is formed by a groove having a uniform depth.

According to a third aspect of the present invention, in the first aspect of the present invention, the wear detecting means is constituted by a plurality of grooves having different depths.

Therefore, according to the present invention, the abutting roller abutting against the image carrier gradually wears against the abutting surface by rotating according to the rotation of the image carrier. For example, if a groove is formed as a wear detecting means, the state of the groove is visually checked or measured with a simple measuring tool to determine whether the developing device has reached the end of its life and is unusable or how long it can be used. It is possible to easily and accurately predict what is possible. For this reason,
It is possible to quickly determine the remaining life of the collected developing device, perform efficient recycling work, and effectively use what has been discarded until now, realizing resource saving. can do.

[0017]

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

First, a schematic configuration of an electrophotographic copying machine having a developing device according to the present invention will be described with reference to FIG.

FIG. 8 is a cross-sectional view of an electrophotographic copying machine, in which a photosensitive drum 11 serving as an image carrier is provided in a main body 10 of the copying machine.
Around the photosensitive drum 11, process devices such as a primary charger 12, a developing device 1, a transfer charger 13, a separation charger 14, and a cleaner 15 are arranged. ing. A hopper 16 for replenishing toner as a developer is provided above the developing device 1.
Is installed.

On one side of the apparatus main body 10, a plurality of paper feed cassettes 17, 18, 1
9 are provided in three upper and lower stages.
A manual feed tray 20 is provided above the tray 7.

Thus, each of the sheet cassettes 17, 18, 19
Or the transfer paper P supplied from the manual paper feed tray 20
Is transported from right to left in the apparatus main body 10 in the figure, and a registration roller 21, a transport belt 22, a fixing device 23, a paper discharge roller 24, and the like are arranged in the transport path.

On the other hand, a lamp 25, reflection mirrors 26 to 29, an optical lens 30, and the like, which constitute an optical system, are arranged in the upper part of the apparatus body 10.

A document (not shown) set on a document table 31 provided on the upper surface of the apparatus main body 10 is read by an optical system, and an optical image of the document is exposed on the rotating photosensitive drum 11. Then, an electrostatic latent image is formed on the photosensitive drum 11, and the electrostatic latent image is developed by the developing device 1 according to the present invention and visualized as a toner image.

On the other hand, for example, a transfer paper P is supplied from a paper feed cassette 17 and the transfer paper P is
The toner image formed on the photosensitive drum 11 is transferred to the transfer section between the photosensitive drum 11 and the transfer charger 13 at the same timing, and then the photosensitive drum 11 is transferred by the operation of the separation charger 14. Separated from

The transfer paper P separated from the photosensitive drum 11 is transported by the transport belt 22 to the fixing device 2.
After the toner image is fixed by the fixing device 23, the toner image is discharged to the outside by the paper discharge roller 24.

Next, the developing device 1 according to the present invention will be described with reference to FIGS.

FIG. 1 is an external perspective view of the developing device according to the present invention, FIG. 2 is an enlarged perspective view of the abutting roller portion of the developing device, FIG. 3 is a perspective view of the abutting roller, and FIG. FIG. 5 is a front view of an abutting roller having grooves of different shapes, FIG. 6 is a front view of an abutting roller formed with two grooves, and FIG. 7 is a developing device according to the present invention. FIG. 4 is a cross-sectional view illustrating a relationship between the photosensitive drum and the photosensitive drum.

In the developing device 1 shown in FIG. 1, reference numeral 2 denotes a developing container, in which toner (not shown) is stored. Reference numeral 3 denotes a lid, and the lid 3 has an opening 3a for supplying toner.

Reference numeral 4 denotes a developing sleeve, both ends of which are rotatably supported by the developing container 2. Reference numerals 5 and 6 denote abutting rollers, which are grooves 5 formed in the center.
The developing sleeve 4 is rotatably supported coaxially with the developing sleeve 4 by b and 6b. Here, the outer diameters of the abutting rollers 5 and 6 are set to be larger than the outer diameter of the developing sleeve 4, and the abutting rollers 5 and 6 abut on the photosensitive drum 11 (see FIG. 8). A predetermined gap is formed between the developing sleeve 4 and the developing sleeve 4. At this time, the abutting rollers 5 and 6 rotate together with the rotation of the photosensitive drum 11.

As shown in FIGS. 2 to 4, the grooves 5a, 5a having a uniform depth are formed on the peripheral surfaces of the abutting rollers 5, 6.
6a are formed.

As the photosensitive drum 11 rotates, the developing sleeve 4 rotates by receiving power transmitted from the input gear 7, and the toner on the developing sleeve 4 forms a toner image on the photosensitive drum 11. At this time, as shown in FIG. 7, the abutting rollers 5, 6 are pressed against the peripheral surface of the photosensitive drum 11 with a constant contact force in the direction of arrow A, so that the photosensitive drum 1
It rotates by following 1. A plastic such as POM is used as the material of the abutting rollers 5 and 6, and the abutting surfaces wear as the durability increases. As the abutting surfaces of the abutting rollers 5, 6 wear, the depth h (see FIG. 4) of the grooves 5a, 6a formed on the peripheral surface gradually decreases, and finally, the grooves 5a. , 6a are lost. If the depth h of the grooves 5a, 6a is set so that the grooves 5a, 6a disappear when, for example, the number of sheets passed through the life of the developing sleeve 4, the state of the grooves 5a, 6a is visually confirmed or By measuring with a simple measuring tool, it is possible to easily and accurately predict whether the developing sleeve 4 has reached the end of its life and is unusable or how long it can be used. For this reason, the remaining life of the collected developing device 1 can be quickly determined, an efficient recycling operation can be performed, and what has been wasted until now can be effectively used. Resources can be saved.

The groove 8a may have a shape as shown in FIG. 5 in addition to the shape shown in FIG.

As shown in FIG. 6, if grooves 9a and 9b having different depths i and j are formed on the peripheral surface of the abutting roller 9, the life expectancy of the developing sleeve 4 can be more accurately determined. it can. Although FIG. 6 shows the case where the number of grooves is two, the number of grooves may be increased as necessary.

[0034]

As is apparent from the above description, according to the present invention, in a developing device provided with a developing sleeve facing the image carrier at a fixed distance, the image carrier and the developing sleeve are fixed. Since the abrasion detecting means is provided on the peripheral surface of the abutting roller provided to keep the distance, the life of the developing device can be easily and accurately determined.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a developing device according to the present invention.

FIG. 2 is an enlarged perspective view of an abutting roller portion of the developing device according to the present invention.

FIG. 3 is a perspective view of an abutting roller of the developing device according to the present invention.

FIG. 4 is a front view of the butting roller shown in FIG. 3;

FIG. 5 is a front view of an abutting roller having a groove of another shape.

FIG. 6 is a front view of an abutting roller formed with two grooves.

FIG. 7 is a cross-sectional view illustrating a relationship between a developing device and a photosensitive drum according to the present invention.

FIG. 8 is a cross-sectional view of an electrophotographic copying machine provided with a developing device according to the present invention.

FIG. 9 is an external perspective view of a conventional developing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Developing device 2 Developing container 3 Lid 4 Developing sleeve 5, 6, 8, 9 Abutting roller 5a, 6a, 8a, 9a, 9b Groove (wear detecting means) 11 Photosensitive drum (image carrier)

Claims (3)

[Claims] 1. A developing device comprising a developing sleeve facing a predetermined distance from an image carrier, wherein a developing roller is provided on a peripheral surface of an abutting roller provided to keep the image carrier and the developing sleeve at a constant distance. A developing device comprising a wear detecting means. 2. The developing device according to claim 1, wherein said wear detecting means is constituted by a groove having a uniform depth. 3. The developing device according to claim 1, wherein said wear detecting means comprises a plurality of grooves having different depths.