JPS581176A - Cleaning device - Google Patents

Abstract

PURPOSE:To perform excellent cleaning free of toner scattering by electrically insulating a cleaning device housing from an image forming device body, and holding it at some potential having the opposite polarity to developer charging polarity. CONSTITUTION:One-component magnetic toner 15 is scraped off from a drum surface by a blade 12 and collected to a magnet roller 10, and the collected toner is scraped off and conveyed through a screw 11. The blade 12 is made of insulating urethane rubber and charged negative, i.e. with the same polarity with the toner 15, and the shafts of the magnet roller 10 and screw 11 are grounded. The potential of a cleaner 8 is held positive, namely, with the opposite polarity to the toner by coupling a housing 13 with a bias power source 14 and then obtaining the control potential of the cleaning device. Consequently, the toner 15 never scatters out of the cleaning device 8.

Description

[Detailed description of the invention] This invention company, 91 details Fi regarding cleaning equipment.

This article concerns Tarinin/atK, a device that inverts Shizukame Senken on a photoreceptor.

Hereinafter, a specific example will be explained with reference to static aaiii.

Figure 1 shows a conventional self-writing forming device (copying machine)
The outline is shown below. 11211 original to be copied, 2 optical systems, 3 photosensitive drum, 4 primary charger, 5 developer, 6 transfer charger, 7 transfer paper cleaning device 8. Photosensitive drum 3#1 The bale uniformly charged by the primary charger 4 is irradiated with the image of the original 1 taken by the optical system 2, and the surface charge or F is generated depending on the qs and dark sK of the original 1.
A patterned latent image of i surface potential is formed. Next, this latent image is converted into IIJIIIgI by the developing device 5.

A magnetic component toner is stored in the developing device 5, and the toner particles are charged to a polarity different from the primary charging polarity in a special manner. In this way, the toner adheres to the drum cover* corresponding to the dark area of the original document 1 that has been converted into an application, and a positive image is obtained in which no toner adheres to the bright area, that is, the drum surface irradiated with light through the optical system.

The image is transferred to the optical fiber transfer paper 7 by the transfer charger 6,
Thereafter, a final copy is obtained through a fixing process (not shown). iIk Final Copy Copy Co., Manuscript 1 and Light/Dark Areas 11Wj
It is a positive image that has the same relationship as 4. On the other hand, the surface of the drum is cleaned by a cleaning device 8) to remove minute amounts of toner particles remaining after one transfer, and the drum is used repeatedly. The cleaning device usually has a housing made of an insulating material such as resin, and a blade that comes into direct contact with the drum roller is made of a highly insulating material such as urethane. Considering the potential of the cleaning device, in the ordinary copying machine shown in FIG. 1, the cleaning device as a whole is charged with a polarity different from that of the toner. This is because the polarity of the transmitted power 4 is the predominant polarity of the charges present on the drum surface 3, and charges of this polarity are accumulated in the cleaning device 8 through the blades in contact with the drum 6.

Figure 2 shows an outline of the area around the drum of a laser beam printer as a specific example of the II document forming scissors used in the company's reversal process. Since the same system^ as in Basic Ka Figure 1 can be used, the same parts are shown with the same symbols. 9 is a scanner that cuts the laser beam into a beam and writes it on the surface of the drum 3. The difference from FIG. 1 is that the polarity of the primary charger 4' is opposite to that in FIG. Then, the drum am charged to -11 is irradiated with a laser beam to form a latent 11tf primary charge 4', and the toner particle 5 containing toner particles charged to the same polarity as the primary charge 4' is turned into an IN. Toner adheres to the bright areas that were irradiated with the Kenrinsha laser beam, and no toner adheres to the dark areas that were not irradiated with the laser beam, resulting in a negative image. The bright areas of the final copy therefore correspond to the areas where the laser beam was not emitted by the scanner 9, and correspond to the areas where the dark laser beam was emitted from the scanner 9.

Now, looking at the potential of the cleaner device 8 in this case, since the dominant charge on the surface of the sensory drum 1 has the same polarity as the toner, as a result of the accumulation, the entire cleaning device 8 has the same polarity as the toner. It will become polar charged. As a result, although this did not occur in the normal copying machine shown in FIG. It has been found that the inconvenience of toner spilling occurs. This is because the entire cleaning device, which is charged to the same polarity as the toner, repels the toner, but the toner falls onto the transfer paper 7, staining the entire surface of the final copy and significantly reducing the image quality. If you do it, it will be K.

The present invention has been made in view of the above-mentioned points, and it is an object of the present invention to provide a good cleaning device that does not cause toner scattering.

In a cleaning device for an image forming device that applies a charged developer of the same polarity to an electrostatic latent formed on a sensory body and performs a reversal process, the cleaning device casing is used to form a lIi letter acid. The main body of the device is electrically insulated and maintained at a polarity potential opposite to the current decharging polarity.

Hereinafter, details of the present invention will be explained using specific examples with reference to the drawings.

Fig. 3 shows the main parts of the embodiment of the invention based on the present invention.
Starier, 12#i blade, 13 is 14t;j
Bias power supply, 1511). Here, for convenience of explanation, it is assumed that a negative charge is applied to the photosensitive drum 5 by the primary charging 4', and that the amount of charge held by the toner 15 is negative. 15 tons of developed one-component magnetic toner!
Toner 1 that adheres to the irradiated area on the surface of the drum 3 and remains after transfer
5 is also present in the irradiated area. -Component magnetic toner 15
is scraped off from the drum surface by the blade 12, and i
Collected by Dunnett Roller 10 and 1 more! The toner scraped off from the Dunnett roller 10 is scraped: L=11
Transported by In this embodiment, the blade 12 is made of insulating urethane rubber, and the blade itself is charged with the same polarity as the toner 15, that is, negatively charged. Further, the shafts of the magnet roller 10 and the screw 11 are grounded. Therefore, looking at the potential of the cleaner 8 as a whole, the casing 13 is connected to the bias power supply 14, which gives the potential of the dominant lien device and is kept in the opposite polarity to the positive toner. rate 12
Although the toner 15 is repelled from the cleaning device f8, there is an electric field attracted from the housing 15, so that the toner 15 does not scatter to the outside from the cleaning device f8. sensory drum 5 part 1
When the transmission power potential is -450V, the t bias voltage is +
Impressive results were obtained by applying 500v or more. Gang!
Even when the shafts of the Dunnett roller 10 and the screw 11 were lifted from the ground potential, the machine remained in the III position.

114HK shows the main parts of another embodiment of the present invention.

Components with the same function as No. 31a are indicated by the same symbol. This is a bias power supply connected to the base I of the 16th photosensitive dome 2^5.

This mourning ME is carried out in the sl letter gtt plus area of the sensory drum 5 by the bias power supply 16. A negative charge of Id-t is applied to the drum surface by the primary charging 4', and the voltage applied by the bias power supply 16 is selected so that the resulting surface potential is in the glass region. Even after 5K, the basic operation of reversal development in which the toner 15 adheres to the area irradiated by the laser remains unchanged, but the developed toner particles 15 are
6 attracts the first lasing induced on the substrate of the drum 3 and is more strongly attracted to the surface of the drum 3.

In this way, the scattering of the toner 15 around the drum 3 is reduced, but during the cleaning process, butterflies and streaks may appear that make it difficult for the toner 15 to peel off from the drum 3. Honjitsu-P1 Company presents a solution to deal with such a case.

That is, the blade 12' is electrically conductive, and at the portion where it contacts the drum 3, the positively charged blade 12' causes the toner 15 to be electrically separated (from the drum 6). Eliminate. In this case, the voltage applied to the bias power supply 14 is
The potential of the board is also higher than that of the housing 15 of the cleaning device 8.
If the potential is biased towards Pfuss by 300v or more,
Good results were obtained in which neither the cleaner failure nor the toner 15 was scattered from the cleaning device 8. Incidentally, in this example, grade 12' was rubber treated with conductivity.
The surface of Photosensitive Dra^5 II! If f is a very large amorphous silicon layer, a metal blade using a thin metal plate may be used.

As described above in detail in the specific examples, the apparatus Fi of the present invention enables good cleaning without the risk of scattering the recovered agent to the surroundings.

Furthermore, in the apparatus 1 of the present invention, by making the cleaning member conductive, it is possible to easily obtain good cleaning conditions.

[Brief explanation of the drawing]

Figure 1 shows an overview of a conventional image forming device that constitutes a regular IA.
! -1 Fig. 2, a schematic diagram of a conventional l1ii image forming apparatus that performs reversal development, Fig. 3, a schematic diagram of a cleaning device based on the present invention, Fig. 4, a schematic diagram of a modified example device based on the present invention . In the figure, 1; manuscript; 2; optical system; 3; sensory drum; 4; -
Power transmitter, 5; developing device, 6; transfer device, 8; cleaning device, 14; power source.

Claims (1)

[Scope of Claims] 0) In a cleaning device of an image forming device which applies a charged developer of the same polarity to an electrostatic latent formed on a photoconductor to produce a reversal image, the cleaning device casing Two II devices. (2) 41 Claims I! 1. A cleaning device according to the invention described in item 1, characterized in that the member that comes into contact with the photoreceptor is electrically conductive.