JPS60254065A - Developing device - Google Patents

Abstract

PURPOSE:To perform invariably development by one development part by providing the developing device with plural development parts and arranging other development parts which are expected to perform developments in an area where development can not be performed when one development part is in a development area. CONSTITUTION:A graip 5 is provided to a hopper 11 and fixed with a lever 61 where a photosensitive drum 3 and a control roll 15 contact each other around an unshown shaft as a fulcrum. The lever 61 is rotatable and fixed by pressing a guide member with a spring. At this time, the photosensitive drum 3 and a sleeve 22 face each other across a gap D2 at the 2nd development part 2, where an objective surface of the photosensitive drum 3 is never developed. When the 2nd development part 2 is put closer to the photosensitive drum 3 and the 1st development part 1 is put sufficiently away from the drum 3, the grip 5 fixed to the developing device is fixed with a lever 62 where a control roll 25 contacts the photosensitive drum 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developing device, and particularly to a developing device having a plurality of developing sections.

Conventionally, multi-color copying machines have been constructed in such a way that a plurality of independent developing devices are arranged close to each other around the latent image carrier so that they can each develop the latent image.
I had to come up with a way to prevent other developing devices from developing. As one example, a method is known in which a shunter is provided in the developing sleeve to prohibit the supply of developer to the developing section, but this method is complicated and may cause aggregation of the developer depending on the type of developer. This may cause fusion to the developing sleeve, resulting in uneven images.

An object of the present invention is to solve a series of drawbacks of the conventional examples.In a developing device having a plurality of developing sections, when one developing section to be developed is in a developing area, the other developing sections By placing the developing area that should not be developed in a non-developing area, only one developing area is always used for development.

Hereinafter, one embodiment of the present invention will be explained in detail with reference to the drawings.

1.2.3 are a sectional view and a perspective view of an embodiment of the developing device of the present invention applied to an electrophotographic copying machine. Although not shown in the figure, a charging mechanism, an image exposure mechanism, a transfer mechanism, a cleaning mechanism, a static elimination mechanism, etc., which are well-known electrophotographic processes, are arranged around the photosensitive drum 3. FIG. 1 is a diagram when the first developing section is placed close to the photosensitive drum so that development is possible, and the second developing section is separated from the photosensitive drum so that development is disabled.

In FIG. 1, 1 of the developing device ioo is a first developing section, and 2 is a second developing section integrated with the first developing section 1. 11.21 is a hopper as a storage device for the developer T, , T, and the hopper 11.21 is integrated with 11a. 12.22 is a cylindrical non-magnetic sleeve (hereinafter referred to as a sleeve) which is rotatably supported in the hopper 11.21, and has magnetic rollers 13 and 23 fixed inside, A portion of the circumference is exposed to the outside from the hopper 11.21 over the entire longitudinal length.

The sleeve 12 is disposed substantially parallel to and facing the photosensitive tram 3 as a latent image carrier with a gap therebetween. Further, above the sleeve 12, a blade 14 facing the sleeve 12 is fixed to the hopper 11. Sleeve 12
supports the developer T1 in the hopper, and after the thickness of the developer is appropriately regulated by the blade 14, the developer is conveyed to the development area and the surface of the photosensitive drum 3 to be developed is developed. Here, the gap DI between the photosensitive drum 3 and the sleeve 12 is kept constant by regulating rollers 15 provided at both ends of the sleeve 12.

The developers T, T2 in the hopper 11.21 are stirred and mixed by a stirring member 16.26. Homper 11.21
'' A rotatable toner replenishment cartridge 18.28 is attached to some of the openings 17.27. Hopper 1
A handle 5 is fixedly attached to the lever 1, and a lever 6 is held at a position where the photosensitive drum 3 and the regulating roller 15 are in contact with each other with a shaft (not shown) as a fulcrum.
It is fixed by 1. Here, the Renaud 61 is rotatable and fixed by pressing the guide member 4 (FIG. 3) with /X.

At this time, the second developing section 2 is connected to the photosensitive drum 3 and the sleeve 2.
2 is the gap DZ, which is sufficiently spaced from the photosensitive drum, and the surface to be developed of the photosensitive drum 3 is not developed in this second developing section.

FIG. 2 is a cross-sectional view in which the second developing section 2 is brought close to the photosensitive drum 3 and the first developing section 1 is sufficiently spaced from the photosensitive drum 3. In the figure, a handle 5 fixed to the developing device is fixed by a lever 62 at a position where the regulating roller 25 contacts the photosensitive drum 3.

FIG. 3 is an explanatory diagram when removing the developing device 100 from the electrophotographic copying machine. In the present invention, a known means is used for sliding and fixing the shaft 4 along a guide rail (not shown) until it comes into contact with the regulating roller 15 or the photosensitive ram 3.

With this configuration, since the regulating rollers 15, 25 are located outside the image area of the photosensitive drum 3, there is no problem even if the regulating rollers 15, 25 come into contact with the photosensitive drum 3 when the developing device is inserted.

The developing device 100 utilizes the property that the first developing section and the second developing section rotate around the shaft 4 as a central axis by moving the handle 5, and selects the developing section that approaches or contacts the photosensitive drum 3. It is something. The method for fixing the developing device 100 is as follows:
Known means such as fixing the handle 5 with levers 61 and 62 by spring pressure are used, and the levers may be operated manually or automatically.

FIG. 4 is an explanatory diagram showing an example of a method for attaching and detaching the developing device 100 in the case of sliding it in the longitudinal direction of the photosensitive tram 3. When the handle 5 is inserted along the lower guide rail 7a and the upper guide rail 8, the sleeve 12.22 remains separated from the photosensitive drum 3, and it is only when the sleeve 12.22 is inserted up to the lower kite rail 7b that the first developing section is The regulating roller 15 and the photosensitive tram 3 are brought into contact. When using the first developing section, it is fixed as it is with the lever 61. When using the second developing section, the handle 5 is rotated in three directions using the lever 62 and fixed.

By adopting the configuration described in "-", for example, if a black developer is used in the first developing section and a red developer is used in the second developing section, black and red copies can be obtained with a single handle. . The type of developer can be either a one-component developer or a two-component developer, and it is magnetic! - Both can be used. Moreover, these can be used in combination as appropriate. Of course, the color of the toner can be selected from not only black and red but also blue, yellow, and stripes as appropriate. Note that it is also possible to use the same developer for general documents and for photographs.

As described above, according to the present invention, a developing device having a plurality of developing sections can be switched and used with a simple operation.

[Brief explanation of drawings]

1 and 2 are side views of an embodiment in which the present invention is applied to an electrophotographic copying device, FIG. 3 is a perspective view for explaining an embodiment of the present invention, and FIG. 4 is an illustration of an insertion guide. FIG. In the figure, 3-1--photosensitive drum, 4-1--guide member, 5-111 handle, 6----reper, 11.21
-111 Hotsuba-112, 22---Sleeve, 15
゜25---Represents one regulation roller. Figure 1 υ1 Figure 2

Claims (1)

[Claims] A plurality of developing sections are provided in an integrated developing device,
A developing device characterized in that when one developing section is opposed to a latent image carrier to perform development, the other developing section is separated from the latent image carrier.