JPS6219883A - Color-changeable developing device - Google Patents

Abstract

PURPOSE:To facilitate color changing operation by providing toner storage chambers which contain toner of colors of developers and are provided with a means which supplies respective contained color toner particles selectively to a developing container integrally for respective developer storage chambers. CONSTITUTION:When development colors are changed, a tank 20 is rotated until a chamber 22 expected to contain a developer of the color in the developing container 5 at present is right below, an opening 24 is aligned with the lower opening 5d of the cylindrical part 5b of the developing container, and a rotary shutter 26. Then when a developing device is put in operation, the developer in the developing container 5 is recovered in the chamber 22. Then, the tank 20 is rotated to put the chamber 22 right above and the upper opening 5c of the cylindrical part 5b is aligned; when the developing device is put in operation, a developer of a color to be changed is supplied from the chamber 22 of the tank 20 to the developing container 5 and the chamber 22 is emptied. The tank 20 is held at the position, the shutter 25 is held open, and the toner supply roller in a toner storage chamber 23 right above it is made ready to operate.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developing device for a monochrome electrophotographic copying machine that uses a two-component developer and can change the developed color.

Recently, single-color copying machines have come on the market that are capable of copying not only black, but also other chromatic colors such as blue, sepia, red, and any other color of your choice.

A common way to change the copy color is to replace the developing unit, but this method causes toner scattering when the developing unit is installed and removed, contaminating the inside and outside of the machine, contaminating the operator, and making operations cumbersome. This has the disadvantage that the color display means of the developing unit installed in the copying machine is complicated.

Furthermore, there are drawbacks such as the intrusion of dust into the developing unit, the shortening of developer life due to the attraction of magnetic materials such as clips and pins due to the magnetic force of the developing sleeve, image abnormalities, and decreased reliability due to damage to the photoreceptor. be.

To improve these, one or more developing units of black and other chromatic colors are installed in advance in the machine along the photoreceptor, and the copy color can be changed by operating a switch on the operation panel. has been proposed. In this method.

Although it makes it easier to switch copy colors, it increases the size of the device, which inevitably increases costs, and if size increases, the frequency of replacing and replenishing the developer and toner for black copying, which is the most frequently used color, increases. However, the number of colors that can be changed can only be applied to two colors, black and one other color.

By the way, the present inventor first attempted to miniaturize the developing device of a black-and-white electrophotographic copying machine that uses a two-component developer.

We proposed a developing device with a new configuration for the purpose of ensuring reliable horizontal agitation of the developer and allowing the user to replace the developer. As illustrated in FIGS. 4 and 5, the developing device includes a developing sleeve 2 disposed opposite to a photosensitive drum 1.
, a developer storage section 3 that stores a two-component developer consisting of toner and a carrier, and a plurality of developer storage sections provided within the storage section 3 that extend radially along the entire length of the hollow shaft 4a in parallel to the developing sleeve 2. An impeller 4 provided with blades 4b is provided in the developer container 5, and the impeller 4 has conveying blades 4 over its entire length.
A spiral developer moving member 6 is fixed to surround b and rotate integrally therewith. Moreover, inside the hollow shaft 4a,
A conveying screw 7 is provided so as to be rotationally driven in a direction that moves the developer in a direction opposite to the conveying direction by the developer moving member 6. Both end faces of the hollow shaft 4a are closed, and a developer inlet 4c and an outlet 4d are provided near the end of one peripheral wall.
is drilled. Impeller 4 to which autopsy moving member 6 is fixedly attached
extends slightly protruding from the front side of the developer container 5,
The side plate 5a of the developer container protrudes into a cylindrical shape that surrounds that portion to allow rotation of the impeller 4, and a developer supply port 5C and a developer discharge port 5d are perforated in the upper and lower portions of this cylindrical portion 5b, respectively. It is set up. A toner cartridge 8 is attached above the impeller 4 of the developer container 5, and a toner supply roller 9 is provided at the lower end of the toner cartridge 8.

During development, the impeller 4 is rotationally driven in the direction shown by the arrow in FIG. As shown, the toner is attracted to the surface of the sleeve 2 by the magnet inside the sleeve 2, the layer thickness is regulated by the doctor 10, and the toner is transported to the developing position facing the photoreceptor drum 1, and the toner is applied to the electrostatic latent image on the photoreceptor drum 1. Supplying and developing,
The developer after development is returned to the developer reservoir 3 in the developer container 5 by the sleeve 2 and circulated. The developer separated by the doctor 10 flows along the separator 11 into the developer storage section 3.
The toner that has decreased due to repeated development is replenished from the toner cartridge 8. The operations described up to this point are the same as before.

On the other hand, when the impeller 4 rotates, the developer moves little by little from right to left in FIG.
It enters the shaft 4a from the inflow port 4c provided at the end of the shaft 4a, moves from left to right by the rotation of the conveying screw 7 provided inside, and when it reaches the right end, exits the hollow shaft from the discharge port 4d. It is discharged and circulated. As a result, the developer is thoroughly stirred and homogenized in the horizontal direction along with the supplied toner.
The stirring device that was conventionally provided near the separator becomes unnecessary, and the device can be made smaller.

The upper and lower openings 5c and 5d of the cylindrical portion 5b of the developer container 5, which surrounds the left end of the impeller 4 (the front side of the device), can be opened and closed by caps 12, respectively, as shown in FIG. 6 when replacing the developer. As shown in the figure, when the lower opening 5d is opened and the first impeller 4 and the conveyance screw 7 are rotated, the developer that has been moved to the left end by the developer moving member 6 falls from the opening 5d under its own weight, so that If a container is attached to the bottom of the developer container 5, the developer in the developer container 5 can be collected. Next, as shown in FIG. 7, when the lower opening 5d is closed and the upper opening 5C is opened, and the developer is fed from above, the developer enters the hollow shaft through the inlet 4c of the hollow shaft 4a. Conveyed to the right by the conveyance screw 7, and discharged to the discharge port 4d.
After all six supply agents stored in the developer storage section 3 are supplied, the developer is uniformly distributed and stored in the storage section 3 by continuing the development drive for a certain period of time.

Furthermore, the present invention solves the above-mentioned problems of the conventional color-changeable two-component developing device.The color change operation is simple, does not require a large space, and the color can be changed between multiple colors. An object of the present invention is to provide a developing device for a monochrome electrophotographic copying machine.

In order to achieve the above-mentioned object, the present invention has been proposed by the present inventor, in which a developer moving member is provided integrally around the periphery, a developer conveying screw is provided inside the hollow shaft, and a developer container is provided. It has an impeller with one end inserted into a cylindrical part protruding from the front side wall of the cylindrical part, and has an impeller with one end inserted into a round cylindrical part, with openings at the top and bottom of the cylindrical part. Utilizing the structure of the provided black and white developing device, the cylindrical portion is rotatably fitted onto the outside, and the interior is divided into a plurality of chambers by radial walls, each of which has a
A developer tank is provided with an opening at a position corresponding to the cylindrical opening of the developer container and a means for opening and closing the opening, and each chamber thereof is a developer storage chamber of a different color. Each of these developer storage chambers is integrally provided with a toner storage chamber that stores toner of the color of the developer and is provided with means for selectively replenishing the stored toner of each color into the developer container. It is characterized by

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a diagram showing the vicinity of the developer and toner tank in an embodiment of the present invention. Other compositions are number 41 first! I7!
The present invention is essentially the same except for the black-and-white developing device and the toner replenishing section previously proposed by the present inventors as explained with reference to FIGS.

As shown in FIG. 1, an annular developer and toner tank 20 is rotatably fitted onto the cylindrical portion 5b of the developer container which rotatably holds the vicinity of the end of the impeller 4 therein. There is. As shown in FIG. 2, the developer and toner tank 20 is divided by a radial wall 21 into four fan-shaped sections. Furthermore, a hopper-like chamber 23 is formed in the radially outer portion of each compartment by a partition wall. The remaining portions 22 of the hopper-shaped chamber 23 are developer storage chambers of different colors, and each chamber has a cylindrical developer container portion 5b.
Openings 24 are provided in the walls facing each other, and a rotary shutter 25 is provided in each opening. Hopper-shaped chamber 2
3 is a toner storage chamber of the color of the developer in the developer storage chamber to which it is attached, and a toner supply roller is installed on the partition wall between the developer storage chamber and the one-turn shutter 25 on the same line. 26 are provided.

In the tank 20, all of the four openings 24 are selectively connected to the upper and lower openings 5c and 5 of the cylindrical portion 5b of the developer container 5.
It is rotated via a transmission device (not shown) to a position that coincides with both of the positions d and can maintain that position.

Since this device is configured as described above, when changing the developing color, first, the chamber 22 (which is empty at this time) that should contain the developer of the color currently contained in the developing container 5 is placed directly below. Rotate the tank 20 to the desired position, and open the opening 2 of the chamber.
4 to the position of the lower opening 5d of the cylindrical portion 5b of the developing container, the rotary shutter 26 is opened, and the developing device is operated.

By the same operation as when collecting the developer in the above-mentioned black and white developing device proposed by the present invention, the developer in the developer container 5 is emptied to accommodate the developer of that color in the tank 20. It is collected in the chamber 22.

Next, the tank 20 is rotated to a position where the chamber 22 containing the developer of the new color is directly above it, and the opening 24 of the chamber 22 and the upper opening of the cylindrical portion 5b of the developer container 5 are opened. 5c and operate the developing device, the developer of the color to be changed is transferred to the tank by the same operation as when new developer is supplied into the developer container in the black-and-white developing device proposed earlier. It is supplied into the developing container 5 from the chamber 22 of 20. When the supply of developer is completed, the chamber 22 becomes empty, but the tank 20 is held in that position, the shutter 251 is kept open, and the toner supply roller 26 in the toner storage chamber 23 directly above it is operated. made possible.

The series of operations described above are performed by key operations on the operation section of the copying machine.

The operation during development is as described above for the black and white developing device. When the toner concentration of the developer decreases below a predetermined range due to repeated development, the toner in the toner storage chamber 23 is passed through the empty developer storage chamber 22 by the toner supply roller 26 and opened. shutter 25,
A predetermined amount is supplied into the developer container 5 via the opening 24+5c.

The developer supplied with toner enters the hollow shaft 4a of the impeller 4 through the opening 4c, is conveyed to the right by the conveyance screw 7, is stirred, and exits through the discharge port 4d to the developer moving member 6.
As the toner is moved slightly to the left, the toner is supplied to the sleeve 2 with a uniform toner density.

In another embodiment shown in FIG. 3, the developer and toner storage tank 20 is rotatably fitted onto the cylindrical portion 5b of the developer container 5, and has a radial wall 21 formed into a plurality of fan-shaped cross-sectional sections. The developer storage chamber 22 and the toner storage chamber 23 are provided adjacent to each other in the axial direction with a partition wall in between. The color of the developer contained in the chamber and the color of the toner are the same.

An opening 24 is provided on the wall facing the cylindrical portion 5b of the developer storage chamber 22, and a rotary shutter 25 for opening and closing the opening 24 is provided. An opening 27 and a toner supply roller 26 are provided, and correspondingly, an opening 5e is provided at the upper part of the developer container cylindrical portion 5b. Therefore, the toner of the color to be developed is delivered to the opening 27 by the toner supply roller 26 from the toner storage chamber 23 located directly above the rotation axis of the tank 20.
．． It is directly supplied into the developing container through 5e.

The other functions are the same as those of the previous embodiment, so the explanation will be omitted.

As described above, according to the present invention, a color-changeable developing device can be housed in an interior space that is almost the same as that of a black-and-white copying machine, so it is possible to change the internal layout of the copying machine. ,
It is possible to avoid increasing the size of the device and increasing costs. Further, since the developer and toner tank are arranged on the front side of the device, it is possible to obtain sufficient amounts of developer and toner, and color changing operations are also facilitated.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the vicinity of the developer and toner tank according to the embodiment of the present invention, and FIG. 2 is a sectional view taken along line u-n in FIG. 1.
FIG. 3 is a sectional view of the developer and toner tank of another embodiment of the present invention, FIG. 4 is a sectional view of the black and white developing device previously proposed, and FIG. 5 is a partially cutaway view of the impeller. The side view shown, and FIGS. 6 and 7 are cross-sectional views for explaining the function. 1... Photoreceptor 2... Developing sleeve 3
...Developer reservoir 4...Impeller 4a...
Hollow shaft 4c...Opening 5...Developer container
5a...Container side plate 5b...Cylindrical portions 5c, 5d, 5e = opening 6...
Developer moving member 7... Conveyance screw 20...
- Developer and toner tank 21...Radial wall 22...Developer storage chamber 23...Toner storage chamber 24.27...Opening 2
5...Shutter (opening/closing means) 26...Toner supply roller, j

Claims (3)

[Claims] (1) a developing sleeve provided opposite to the photoreceptor; a developer storage section for storing a two-component developer consisting of toner and carrier; and a developer storage section provided on the storage section in parallel with the developing sleeve;
The developing sleeve has an impeller provided with a plurality of conveying blades radially along its entire length inside the developing container, and the developing sleeve holds and conveys the developer supplied by the impeller to form a latent image on the photoreceptor. In the developing device of the electrophotographic copying machine, the developer is supplied with toner to perform development, and the developer after the development is returned to the developer reservoir for circulation. A spiral developer moving member is fixed therein, and the shaft of the impeller is formed hollow, and developer inflow and discharge ports are provided on the circumferential wall at both ends of the impeller. A conveyance screw for conveying the developer is provided, and the impeller extends and slightly protrudes from the side surface of the developer container, and the side plate of the developer container protrudes into a cylindrical shape that surrounds that portion to allow rotation of the impeller. Openings for supplying and discharging developer are provided at the upper and lower parts of the cylindrical part, respectively, and the cylindrical part is rotatably fitted onto the outside, and the interior is divided into a plurality of chambers by a radial wall, each of which has a developer supply and discharge opening, respectively. It has a developer tank provided with an opening and a means for opening and closing the opening at a position corresponding to the opening of the cylindrical part of the developer container, and each chamber is a developer storage chamber of a different color. Each developer storage chamber contains toner of the color of the developer, and a toner storage chamber is integrally provided with a means for selectively replenishing the stored toner of each color into the developer container. Color-changeable developing device. (2) The above color toner storage chambers are provided radially outward of each developer storage chamber, and the toner in the toner storage chambers is replenished into the developer container through the empty developer storage chamber. A developing device according to claim 1, characterized in that: (3) The above-mentioned toner storage chambers of each color are integrally arranged side by side on the side surface of each developer storage chamber in the direction of the rotation axis, and the toner of each color is directly fed into the developer container through an opening further provided at the top of the cylindrical portion of the developer container. 2. The developing device according to claim 1, wherein the developing device is directly supplied.