JPS61165778A - Developing device - Google Patents

Abstract

PURPOSE:To make the device small and to decrease a space necessary to a developing device by constituting mutually respective developing devices in a single body and detaching at least one developing device or above for other developing devices, in the multi-color developing device composed of plural developing devices. CONSTITUTION:The first developing device 1 and the second developing device 2 are overlapped adjoining to each other in the upward and downward directions, fitted unitedly and detachably by the linking means and the developing device 1 is slided in the side direction of a drum S in the upward and downward directions. When the developing device 2 is used for developing, a lever 61 is driven in the downward direction by a plunger, the whole of the multi-color developing device is pushed down, and then, an interval D2 is set to the prescribed value by a regulating roller 25, and on the other hand, the developing device 1 is separated from a photosensitive drum S sufficiently. To the developing device 1, for example, a black developing agent is used or to the developing device 2, a red developing agent is used, and the lever 61 is operated, and then, black and red copied matters can be easily obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multicolor developing device for an image forming apparatus such as a color electrophotographic copying device or a color recording device of a computer output section, and particularly relates to a multicolor developing device for developing two or more monochrome colors. The present invention relates to a multicolor developing device that can be suitably used in color, so-called multicolor, electrophotographic copying devices, and even full color electrophotographic copying devices. Although the following description will be made in connection with a copying apparatus, the present invention is not limited thereto.

In recent years, the demand for color copying has increased, and it is desired that the quality of color copy images be improved, and that copying machines be made smaller and lower in price.

One of the important problems to be solved in order to meet such demands is how to configure a developing device for developing latent images of each color formed on a latent image carrier, such as a photoreceptor, as follows.

Currently, in commercially available color copying devices, a plurality of independent developing devices each having a developer of each color are arranged in parallel along the photoreceptor, and one developing device is selected for development. Developing devices are widely used.

Although such a side-by-side multicolor developing device has the advantage of a simple configuration, the overall structure of the multicolor developing device becomes large, and the space occupied by the developing device inevitably becomes large.

In order to solve the above-mentioned drawbacks of the conventional developing device, attempts have been made to integrate a plurality of independent developing devices. However, for example, when a developing device is made disposable to simplify maintenance, the developer is used differently in each developing device, so when one developing device runs out of developer, it is not necessarily the case that all developing devices are used. The developer does not necessarily run out, and therefore, when the developing device is discarded, the remaining developer must also be discarded, which is not only uneconomical but also undesirable as it stains the surrounding area.

In addition, the number of developing devices that make up an integrated multicolor developing device is limited, and therefore, if the copy color is to be different, the entire multicolor developing device must be replaced with another multicolor developing device. The replacement work is difficult. Furthermore, there is a disadvantage that the replacement developing device itself is expensive.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a developing device which is considerably smaller in size than conventional multi-color developing devices and which can reduce the space required for the developing device.

Another object of the present invention is a multi-color developing device in which at least one developing device is configured to be detachable from other developing devices and is disposable, thereby simplifying maintenance and facilitating replacement of developing devices. The goal is to provide the following.

The above aspects are completely achieved by the present invention. In summary, the present invention provides a developing device comprising a plurality of developing devices, in which each developing device is configured integrally with one another, and at least one developing device is configured to be detachable from other developing devices. According to a preferred embodiment of the present invention, the removable developing device has a small developer storage capacity, and the developer storage capacity of the removable developing device is smaller than that of other developing devices. This is less than half of the developer storage capacity.

Next, one embodiment of the developing device according to the present invention will be described in detail with reference to the drawings.

Referring to FIGS. 1 and 2, a developing device 100 according to the present invention is shown applied to a two-color multicolor electrophotographic copying apparatus, and therefore a first developing device l and a second developing device
Although the developer device 2 includes two developers, it should be understood that the developer device of the present invention is not limited thereto, and may have three or more developers.

The first developing device 1 and the second developing device 2 are arranged along the image carrier, in this embodiment, the photosensitive drum S, and both the developing devices 1 and 2 are connected to a guide rail 41 provided on the first developing device L. To, the second
By fitting the rails 42 attached to the developing device 2, the developing device 2 is constructed integrally with an attachment/detachment opening.

The photosensitive drum S is equipped with, for example, a charging mechanism necessary for an image forming process, in which an electrostatic latent image is formed on the surface of the photosensitive drum S by a well-known image forming process before reaching the developing area where the developing device 100 is arranged. , an image exposure mechanism, a transfer mechanism, a cleaning mechanism, a static elimination mechanism, etc. are not shown.

Next, the first developing device 1 and the second developing device 2 will be explained.

The first developing device 1 includes a container or hopper 11 for storing developer TI, and a cylindrical non-magnetic sleeve (hereinafter simply referred to as "sleeve") is inserted into an opening formed on the side of the hopper 11 facing the photosensitive drum S. )12 are placed. A part of the circumference of the sleeve 12 is exposed to the outside from the hopper 11 over the entire length in the longitudinal direction, and a magnet roller 13 is provided inside the sleeve 12.

A blade 14 is disposed above the sleeve 12 so as to face the sleeve 12, and controls the amount of the developer carried by the sleeve 12 in the hopper 11 brought to the development area, that is, the thickness of the developer on the sleeve 12. do. The gap D1 between the photosensitive drum S and the sleeve 12 is kept constant by regulating rollers 15 provided at both ends of the sleeve 12.

The hopper 11 is configured such that a replenishment cartridge 18 can be attached thereto, and developer is replenished from the cartridge 18 as appropriate. The developer in the hopper 11 is stirred and mixed by the stirring member 16, and the developer with a uniform concentration is supplied to the sleeve 12.

The second developing device 2 has substantially the same structure as the first developing device 1, except that it has a smaller developer storage capacity. That is, the second developing device 2 includes a container or hopper 21 that stores the developer T2, and a cylindrical non-magnetic sleeve (hereinafter simply referred to as (referred to as "sleeve")2
2 is placed. A part of the circumference of the sleeve 22 is exposed to the outside from the hopper 21 over the entire length in the longitudinal direction, and a magnet roller 13 is provided inside the sleeve 22.

A blade 24 is disposed above the sleeve 22 so as to face the sleeve 22, and determines the amount of developer carried by the sleeve 22 in the hopper 21 brought to the development area, that is, the sleeve? Regulates the thickness of the developer on z. The gap D1 between the photosensitive drum S and the sleeve 22 is kept constant by regulating rollers 25 provided at both ends of the sleeve 22.

The hopper 21 is configured such that a replenishment cartridge 28 can be attached thereto, and developer is replenished from the cartridge 18 as appropriate. The developer in the hopper 11 is stirred and mixed by the stirring member 16, and the developer with a uniform concentration is supplied to the sleeve 12.

The first developing device and the second developing device configured as described above are stacked adjacent to each other in the vertical direction, and can be integrally attached and detached by connecting means provided on the first developing device and the second developing device 2. Can be installed freely. Although such a connecting means may have an arbitrary configuration, for example, as shown in FIG.
2, and the rail 42 is slidably fitted to the guide rail 41.

The entire multicolor developing device, that is, the first and second developing devices 1 and 2 are arranged so that the first developing device is slidably moved in the vertical direction on the side of the drum S. Various structures may be considered for this purpose, but for example, the first developing device l is attached to a guide member (not shown) provided in the main body of the copying machine so as to be slidable in the vertical direction, and the lever 61 is attached to the guide member (not shown) provided in the main body of the copier. By acting on a protrusion 5 fixed to the first developer l, the first developer l can be moved to a predetermined position and fixed. As a result, the second developing device will also be moved in the vertical direction together with the first developing device l.

Therefore, when the second developing device 2 is used for development, the lever 61 is driven downward by a plunger (not shown) to lower the entire multicolor developing device from the state shown in FIG. 1 to the state shown in FIG. When pushed down in the direction, the distance between the photosensitive drum S and the sleeve 22 becomes a gap DZ, and the distance is set to a predetermined value by the regulating rollers 25. On the other hand, the first developing device 1 is sufficiently spaced from the photosensitive drum S, and the image to be developed on the photosensitive drum S is not developed by the first developing device 1.

On the other hand, when the 1yL imager l is used for development, the lever 62 is driven upward by a plunger (not shown), and the entire multicolor developing device moves upward from the state shown in Fig. 2 to the state shown in Fig. fIIJ1. When the sleeve 12 is pushed up, the distance between the photosensitive drum S and the sleeve 12 becomes a gap D1.
is set to a predetermined value. On the other hand, the second developing device 2 is sufficiently spaced apart from the photosensitive drum S.
The image to be developed on the photosensitive drum S is not developed.

In the above description, the entire multicolor developing device, that is, the first and second developing devices 1 and 2, was described with the first developing device sliding in the vertical direction on the side of the drum S. A pivot shaft (not shown) is provided on the side of the developing device I, and the first developing device I is configured to swing toward and away from the drum S around the pivot shaft, and the second developing device I is configured to swing toward and away from the drum S. The developing device 2 moves so as to be in contact with the drum S when the first developing device l moves away from the drum S, and moves into contact with the drum S when the first developing device I is driven so as to come into contact with the drum S.
The developing device 2 can be configured to move away from the drum S.

As can be understood from the above description, in either configuration, the developing operation is performed by the first developing device 1 in the state shown in FIG. 1, and the developing action is performed by the second developing device I in the state shown in FIG.

With this configuration, for example, if a black developer (frequently used) is used in the first developer 1 and a red developer (special purpose) is used in the second developer 2, the lever 61 can be activated. As a result, black and red copies can be easily obtained, and since the second developing device 2 can be easily removed from the first developing device 1 by pulling it out toward the front, only the second developing device 2 can be made disposable. It has become possible. Furthermore, by simply replacing only the second developing device with a developing device using developers such as blue, yellow, and brown, it has become possible to copy more types of colors.

The type of developer may be either an l-component developer or a two-component developer, and both magnetic toner and non-magnetic toner can be used. Moreover, these can be used in combination as appropriate. Of course, the color of the toner can be appropriately selected from not only black and red but also blue, yellow, brown, etc. It is also possible to use the same developer for general documents and photographs.

In the above embodiment, when one developing device is developing in an integrated developing device having a plurality of developing devices, as a method for preventing the other developing devices from developing, the other developing devices are separated from the surface of the photosensitive drum. However, a known method may be used in which a shutter is provided on the developing sleeve of a developing device that is not used for development to prohibit the supply of developer to the developing section.

A suitable developer storage capacity ratio between the first developing device, that is, the main developing device 1, and the second developing device, that is, the reverse developing device 2 was studied. The results were as follows.

With the above configuration, a black developer is used in the main developer 1 and a red developer is used in the reverse developer 2.

I did a monitor test.

The results are shown in Tables 1 and 2. However, the conventional example is an example of calculation when the hopper capacities of the main developing device and the hopper capacity of the main and sub-developing devices of the embodiment are equal, and the hopper capacities of the main and sub-developing devices are also equal.

Comparing IQ and the number of toner replenishments per 1,000 sheets (total of main developer and secondary developer), No. 1 is 3.3 in the conventional example.
33 times is 3 times in the example, and No. 2 is 3 times in the conventional example.
．． 33 times is 2.88 times in the example.

By making the hopper capacity of the main developing device relatively larger than that of the secondary developing device in this way, it is possible to reduce the number of times of toner replenishment within the limited space of the developing device.

The appropriate ratio of the hopper capacity of the main developer and the secondary developer varies depending on the type of developer used and how the user uses it, but it cannot be generalized, but the hopper capacity of the main developer should be at least twice that of the secondary developer. preferable.

FIGS. 3 and 4 are cross-sectional views of another embodiment, in which a first main developer l is arranged around the photosensitive drum S, and a second subsidiary developer is detachably attached to the first developer l. Vessel 2. The embodiment shown in FIG. 3, which shows a developing device 100 in which a third sub-developing device 4 is detachably attached to the second developing device, is different from the embodiment shown in FIGS. 1 and 2. Similarly, the developing device 100 is moved in the vertical direction, but in the embodiment shown in FIG. The supply of developer to the developing section is prohibited by a known method, such as applying a shutter to each developing device or covering the developing sleeve of the developing device that is not used for development with the shutter. In such a configuration, in the hopper 11 of the first developing device, the hopper 21 of the second developing device, and the hopper 31 of the third developing device, when the capacity of the hopper 11 of the first developing device is 100, the capacity of the hopper 21 is 50. , the capacity of the hopper 31 is 30. Black developer T1 is used in the first main developer, red developer T2 is used in the second sub-developer, and so on.
A test was conducted using green developer T3 in the third developer. The results are shown in Tables 3 and 4.

However, the conventional example is a calculation example in which the la hopper capacity is equal to that of the embodiment, and the hopper capacities of one main developer and two sub-developers are equal.

Comparing the number of toner replenishments per 10,000 sheets, N
For No. 3, the conventional example requires 4.17 times, but in the embodiment, 3.17 times, and for No. 4, the conventional example requires 2.90 times, instead of 4.17 times.

11 Standing J As explained above, since a plurality of developing devices are integrated and at least one developing device is detachable from other developing devices, the developing device can be made smaller and cheaper. It has the effect of

Furthermore, by making the hopper capacity of the main developer relatively larger than the hopper capacity of the secondary developer, there is an advantage that the number of toner replenishments can be reduced within the limited developing device space. .

[Brief explanation of drawings]

FIG. 1 is a side view of an embodiment in which the present invention is applied to an electrophotographic copying apparatus, and shows a first developing device in an operating state. FIG. 2 is a side view of the developing device of FIG. 1, showing the second developing device in operation. 3 and 4 are side views of another embodiment in which the present invention is applied to an electrophotographic copying apparatus. 1: first developing device 2: second developing device 3: third developing device 6: lever 11.21.31: hopper 12.22.32 sleeve 15.25.35: roller 41 guide rail 42: rail 61. 62 Nilever 100: Developing device

Claims (1)

[Scope of Claims] 1) In a developing device consisting of a plurality of developing devices, each developing device is configured integrally with one another, and at least one or more developing devices are configured to be detachable from other developing devices. A developing device characterized by: 2) The apparatus according to claim 1, wherein the removable developing device is a developing device with a small developer storage capacity. 3) The apparatus according to claim 2, wherein the developer storage capacity of the detachable developing device is less than half of the developer storage capacity of the other developing devices.