JPH10333517A - Toner recycling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a large-sized stirring member and to miniaturize tone whole of a device by supplying fresh toner to a carrying screw, so as to sufficiently mix waste toner and the fresh toner in the process of carrying, at the time of carrying the waste toner recovered with a cleaning device to the side of a developing device, with the carrying screw. SOLUTION: When toner in the developing device 18 is reduced, the fresh toner in a toner hopper 36 is supplied to a carrying screw 42 by an agitator 40, in accordance with a detection signal issued by a toner sensor and while mixing, the fresh toner and the waste toner scraped by the blade 38 of the cleaning device 22 are carried by the carrying screw 42, to be dropped on a carrying screw 26 at the end part of the carrying screw 42. While mixing, the mixed toner dropped on the carrying screw 26 is further carried up to the developing device 18 by the carrying screw 26, to be dropped on a stirring screw 30 at the end part of the carrying screw 26. Then, the dropped mixed toner is sufficiently stirred by the stirring screws 30 and 32, to be triboelectrified and then, supplied to a developing roller 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner recycling apparatus and, more particularly, to a toner recycling apparatus for reusing toner remaining on a photoreceptor in an image forming apparatus such as an electrophotographic printer.

[0002]

2. Description of the Related Art An example of such a conventional toner recycling apparatus is disclosed in Japanese Patent Application Laid-Open No. 7-43996 [G03G 15/0].
8]. According to this conventional technique, the waste toner collected by the cleaning device 9 is returned to the toner supply container 10 filled with the new toner by the conveying screw 9B, and the waste toner and the new toner are rotated by rotating the stirring member 15 in the toner supply container 10. And the mixed toner is supplied to the developing device 4.

[0003]

According to the prior art, the waste toner and the new toner can be sufficiently mixed by the stirring member 15, so that it is possible to prevent the waste toner from being directly supplied to the developing device and deteriorating the image quality. Although possible, a large stirring member 15
However, there is a problem that the size of the entire apparatus is increased due to the necessity.

[0004] Therefore, a main object of the present invention is to provide a toner recycling apparatus capable of reducing the size of the entire apparatus.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a toner recycling apparatus which mixes waste toner collected by a cleaning device and new toner and supplies them to a developing device. And a supply unit that supplies new toner to the transport screw.

[0006]

When the waste toner collected by the cleaning device is transported by the transport screw, new toner is supplied to the transport screw. Therefore, in the course of conveyance by the conveyance screw, the waste toner and the new toner are sufficiently mixed, and the mixed toner is supplied to the developing device.

[0007]

According to the present invention, since the waste toner and the new toner can be sufficiently mixed by the transport screw, it is not necessary to separately provide a large stirring member as in the related art. Therefore, the entire device can be downsized. The above object of the present invention,
Other objects, features and advantages will become more apparent from the following detailed description of embodiments, which proceeds with reference to the accompanying drawings.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A toner recycling apparatus 10 of this embodiment shown in FIGS. 1 and 2 includes a photosensitive drum 12 rotated by a motor (not shown). Around the photoreceptor drum 12, the chargers 14 and
The exposing device 16, the developing device 18, the transfer roller 20, the cleaning device 22, and the static eliminator 24 are arranged, and a transport screw 26 is arranged from below the cleaning device 22 to above the developing device 18.

The charger 14 is for uniformly charging the surface of the photosensitive drum 12 to a constant potential. L is applied to the surface of the photosensitive drum 12 charged by the charger 14.
When an exposure device 16 such as an SU (laser scanning unit) irradiates a laser beam corresponding to data, an electrostatic latent image corresponding to the photoconductive characteristic is formed on the surface of the photosensitive drum 12. .

The developing device 18 includes a developing roller 28 and two stirring screws 30 and 32. Developing device 1
A one-component or two-component developer containing toner is accommodated in the inside of toner cartridge 8, and sufficiently charged toner stirred by stirring screws 30 and 32 is moved to a position where the toner is opposed to photosensitive drum 12 by developing roller 28. Conveyed. Then, the electrostatic latent image on the photosensitive drum 12 is developed with toner by the action of the developing bias voltage applied to the developing roller 28.

The transfer roller 20 is for transferring the toner image formed on the photosensitive drum 12 to the recording paper 34. The recording paper 34 to which the toner image has been transferred by the transfer roller 20 is conveyed to a fixing device (not shown), and the toner image is thermally fixed by the fixing device. Cleaning device 22
Are the toner hopper 36, blade 38, agitator 40
And the transfer screw 42, and the toner hopper 36 is filled with new toner. The toner remaining on the surface of the photosensitive drum 12 without being transferred to the recording paper 34 is scraped off onto the transport screw 42 by the blade 38.

The static eliminator 24 is for irradiating the surface of the photosensitive drum 12 with light to remove residual charges. After the residual toner is scraped off, the residual charge is removed from the photosensitive drum 12 by the static eliminator 24 and the photosensitive drum 12 is again charged.
Is charged uniformly. When such a series of image forming processes is repeated, the amount of toner in the developing device 18 decreases. In this embodiment, however, a toner shortage is detected by a toner sensor (not shown). Then, the agitator 40 and the conveying screws 42 and 26 are rotated according to the detection signal generated by the toner sensor, whereby the insufficient toner is replenished. That is, the toner hopper 3
6 is supplied to the transport screw 42 by the agitator 40, and the new toner and the waste toner scraped off by the blade 38 are transported while being mixed by the transport screw 42. At the end of the transport screw 42, 26 is dropped. The mixed toner dropped on the transport screw 26 is transported to a position above the developing device 18 while being further mixed by the transport screw 26, and is dropped on the stirring screw 30 at the end of the transport screw 26. Then, the toner is sufficiently stirred by the stirring screws 30 and 32 to be triboelectrically charged, and then supplied to the developing roller 28. When there is no more new toner in the toner hopper 36, new toner is supplied by the toner cartridge.

According to this embodiment, the waste toner and the new toner can be sufficiently mixed by the conveying screws 42 and 26, so that only the waste toner can be prevented from being directly supplied to the developer, and the deterioration of the image quality can be prevented. it can. Further, since it is not necessary to separately provide a large stirring member as in the related art for mixing the toner, the entire apparatus can be downsized.

Since the toner hopper 36 is provided on the cleaning device 22 side, the space above the developing device 18 can be effectively used. In the above-described embodiment, the toner hopper 36 is provided only on the cleaning device 22 side. However, for example, like the toner recycling device 44 shown in FIG.
The toner hopper 50 may be provided only on the developing device 18 side, as in a toner recycling device 48 shown in FIG.

In the toner recycling device 44 (FIG. 3),
A transport screw 52 and an agitator 54 are provided in the toner hopper 46. When a toner sensor (not shown) issues a detection signal, the new toner in the toner hopper 46 is supplied to the transport screw 52 by the agitator 54 and dropped onto the transport screw 26 at the end of the transport screw 52. Then, the toner is conveyed to a position above the developing device 18 while being further mixed with the mixed toner sent from the cleaning device 22, and dropped onto the stirring screw 30 at the end of the conveying screw 26.

As described above, when the toner hoppers 36 and 46 are provided in association with the cleaning device 22 and the developing device 18, respectively, the filling amount of the new toner can be increased, so that a process cartridge having a long life can be configured. On the other hand, the toner recycling device 48 (FIG. 4)
In this case, a cleaning device 56 without a toner hopper is used. When a toner sensor (not shown) generates a detection signal, the waste toner scraped off by the blade 38 is transported by the transport screw 42 as it is, and the transport screw 4
At the end of No. 2, it is dropped on the conveying screw 26. And
In the process of being transported by the transport screw 26, the toner is sufficiently mixed with the new toner supplied from the transport screw 52.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is a perspective view showing the embodiment of FIG. 1;

FIG. 3 is an illustrative view showing another embodiment of the present invention;

FIG. 4 is an illustrative view showing another embodiment of the present invention;

[Explanation of symbols]

 10, 44, 48 toner recycle device 12 photoreceptor drum 18 developing device 22, 56 cleaning device 26, 42, 52 conveying screw 28 developing roller 30, 32 stirring screw 36, 46 toner hopper 38 blade 40, 54 ... Agitator

Claims (3)

[Claims] 1. A toner recycling device for mixing waste toner and new toner collected by a cleaning device and supplying them to a developing device, wherein the waste toner is conveyed from the cleaning device side to the developing device side. Comprising a feeding screw for supplying the new toner to the feeding screw and the feeding screw,
Toner recycling device. 2. The toner recycling apparatus according to claim 1, wherein said supply means includes a first toner hopper provided in connection with said cleaning device. 3. The toner recycling apparatus according to claim 1, wherein said supply means includes a second toner hopper provided in association with said developing device.