JPS60257478A - Magnetic brush cleaning device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of leak and the degradation of destatisizing effect to improve the reliability of cleaning by attracting and recovering a cleaning agent, which is detached from a magnetic brush forming member, etc., by a magnetic roll provided between the magnetic brush forming member and a destaticizing charger. CONSTITUTION:A magnetic material carrier to which a toner remaining on a photosensitive drum 2 is stuck and removed is transferred from a cleaning sleeve 5 successively by the first and the second drawing-up sleeves 9 and 11 and is separated from the surface of the second drawing-up sleeve 11 in the position, where the magnetic field of the second drawing-up sleeve 11 is weakened, and is guided by a scraper 13 and is slided down on the scraper 13. This carrier passes between a toner recovering roll 14 and a counter electrode 15 and is returned into a carrier tank 6, and the toner stuck to the carrier is attracted to the toner recovering roll 14 and is separated and recovered. At this time, the magnetic material carrier separated and dropped from the cleaning sleeve 5 and the circulating route and the toner stuck to this carrier are attracted to the outside peripheral surface of a carrier catch magnet roll 22 and are peeled by a blade 25 and are dropped into a toner saucer 26.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning device for an electrophotographic copying device, etc., and more particularly, to a magnetic brush cleaning method that uses a magnetic brush to remove untransferred toner remaining on the surface of a photoreceptor. Regarding equipment.

In general, an electrophotographic copying device forms an electrostatic latent image corresponding to an original image on the surface of a membrane-shaped or belt-shaped photoreceptor (by charging and exposing it to light). Toner is applied, visualized, transferred to transfer paper, and fixed to form a copy of the original.

By the way, in this case, it is difficult to transfer all the toner on the surface of the photoconductor to the transfer paper in the transfer process, and after the transfer process, some untransferred toner remains on the surface of the photoconductor.
If the next copying process is performed in this state, the remaining toner will be transferred together with the newly formed toner image, resulting in a significantly poor copy quality. .

Therefore, after the transfer process is completed, untransferred toner remaining on the surface of the photoreceptor is generally removed by a cleaning device.

An example of such a cleaning device 7 is a magnetic brush cleaning device as schematically shown in FIG.

The magnetic brush cleaning device 1 is disposed around the photosensitive drum 2 rotating in the direction of arrow P, following the static eliminating charger 6, and starts operating at the same time as printing starts.

Then, the cleaning sleeve 5, which is a magnetic brush forming member provided inside the casing 4, is supplied with an appropriate amount of the magnetic carrier, which is the cleaning agent that has been retained in the carrier tank 6.

Inside the cleaning sleeve 5, six magnets 7 are fixedly installed with their N poles and S magnets facing the inner circumferential surface of the cleaning sleeve 5 alternately. A magnetic brush is formed by being magnetically attracted to the outer circumferential surface of the magnetic brush in the form of a brush.

The magnetic brush moves as shown by the imaginary line arrow by the rotation of the cleaning sleeve 15 in the direction of the arrow Q and comes into contact with the surface of the photosensitive drum 2 after the transfer process, and removes the untransferred toner T remaining there. capture and remove.

Thereafter, when the magnetic carrier with the toner attached to it from the cleaning sleeve 5 reaches a position where the magnetic field by the magnet 7 is weakened, it is attracted by the magnet 10 fixedly installed inside the first cleaning sleeve S. First
The first pumping sleeve 9 is rotated in the direction of the arrow S, and transferred upward.

Furthermore, the magnetic carrier on the first pumping sleeve S is
When it reaches a position where the magnetic field by the magnet 10 is weakened, it is attracted by the magnet 12 fixedly installed inside the second pumping sleeve 11 and transferred onto the second pumping sleeve 11, and the arrow of the second pumping sleeve 11 It is transported by rotation in the T direction. .

Then, when the magnetic field generated by the magnet 12 becomes weaker, the magnetic carrier on the second pumping sleeve 11 moves away from the second pumping sleeve 11 F: to the scraper 1.
3, slides down at l'L, passes between the toner collection roller 14, which is a toner collection member that rotates in the direction of arrow R, and the rond-like opposing electric current TRI 15, and then slides down to the carrier tank 6.
fall inside.

At this time, a voltage having the opposite polarity to the charging polarity of the toner, that is, the same polarity as the charging polarity of the photoreceptor tram 2, is applied to the toner collection roller 14, and the counter electrode 15 is either grounded or the voltage is applied to the toner collection roller 14. A voltage smaller than the voltage applied to the

Thereby, the toner collection L'-ra 14 and the counter electrode 15
When the magnetic carrier passes through an electric field formed between
Only clean magnetic carrier is supplied to the carrier tank 6.

That is, the magnetic carrier, which is a cleaning agent, is circulated and used in the path shown by the imaginary line arrow in the figure.

- h. The toner adhering to the outer peripheral surface of the toner collection roller 14 is peeled off by the big-off blade 16 and falls into the 1-toner receiving tray 17, and is discharged from the apparatus by the screw conveyor 18 and reused.

However, in such a conventional magnetic brush cleaning device, the magnetic carrier, which is a cleaning agent that is attracted to the outer circumferential surface of the cleaning sleeve 5 and forms a magnetic brush, is attached to the photoreceptor tram 2 during and after rubbing. The structure is such that toner adheres to the toner and tends to separate from the cleaning sleeve 5 and scatter during movement.

Therefore, there is a problem in that the scattered magnetic carriers and the toner attached thereto adhere to the static elimination charger 3, contaminating the inside of the recasing where the leak has occurred, and reducing the static elimination effect.

The invention of Yutaka Mimi was made by focusing on the above-mentioned problem, and prevents the cleaning agent separated from the magnetic brush forming member etc. from adhering to the static elimination charger, thereby preventing the occurrence of leakage in the static elimination charger and eliminating static electricity. The first objective is to prevent a decrease in effectiveness.

0- The configuration of the present invention will be described below based on embodiments.

FIG. 2 is a schematic configuration diagram schematically showing an example of a magnetic brush cleaning device embodying the present invention. Parts corresponding to those in FIG. 3 is omitted. This magnetic brush cleaning device 20 has a cleaning sleeve 5
A carrier catch macro roll 22, which is a magnetic roll that attracts the cleaning agent separated from the photosensitive drum 2, is provided close to the photoreceptor drum 2.

This carrier catch macro roll 22 rotates in the direction of arrow (J) at the same linear velocity as the six-body drum 2 (IU), and the surface that comes close to or lightly contacts the outer peripheral surface of the photoreceptor drum 2 is the outer periphery of the photoreceptor drum 2. It is made to move in the same direction at the same speed as the surface.

Also, inside this carrier catch macrol 22, two magnets 23 and 24 are placed, one of which is N +1,
On the other hand, the S pole is fixedly placed opposite to the inner circumferential surface of the carrier catch mag roll 22.

Further, the tip end of a blade 25 whose base end is fixed to the housing 21 is in contact with the outer circumferential surface of the blade 25 .

Furthermore, a saucer 26 and a discharge screw conveyor 27 are disposed at the lower corner of the housing 21 in close proximity to the plate 25, and these remove the cleaning agent (carrier) adsorbed onto the carrier catch macrol 22. It constitutes a cleaning agent recovery means for recovering the cleaning agent.

In this embodiment, an exhaust passage 28 is further provided on the side surface of the casing 21 near the carrier catch macrol installation part,
An exhaust fan is installed inside this exhaust passage 28.

Next, the operation of this embodiment configured as described above will be explained.

In this magnetic brush cleaning device 20 as well, the print start rotates each sleeve and roller and applies voltage to the toner collection roller 14 in the same manner as in the prior art, and a magnetic brush is formed on the cleaning sleeve 5 to form a magnetic brush on the photoreceptor. The magnetic gear from which the toner remaining on the tram 2 has been removed is removed from the cleaning sleeve 5 by the first. It is sequentially transferred by the second pumping sleeve 7 9, 11, and when the magnetic field of the second pumping sleeve 11 becomes weak, it leaves the top of the second pumping sleeve 11 and is guided by the scraper 13 and slides thereon. Fall,
The toner passes between the toner collection roller 14 and the counter electrode 15 and returns to the carrier tank 6, and the toner adhering to the carrier is adsorbed by the toner collection roller 14 and separated and collected.

At this time, the magnetic carrier (cleaning agent) that leaves the cleaning sleeve 5 and the circulation path and falls and the toner attached thereto are attracted to the outer peripheral surface of the carrier catch macro roll 22 by the magnetic fields of the magnets 2 and 24. , the toner particles move as the carrier catch macro roll 22 rotates in the direction of arrow U, are peeled off by the blade 25, fall into the toner tray 26, and are discharged from the apparatus by the screw conveyor 27.

Note that the carrier catch mag roll 22 rotates at the same linear speed as the photoconductor tram 2 in the same direction as the movement direction of its outer circumferential surface, so even if the carrier catch mag roll 22 comes into contact with the photoconductor tram 2, its rotation will not occur. will not affect.

Further, in this embodiment, even if the toner leaves the carrier and scatters from the cleaning sleeve 5 or the circulation path indicated by the imaginary line arrow, it is sucked in by the exhaust fan 2 and discharged to the outside from the exhaust passage 28.

This prevents magnetic carriers and toner from adhering to the static elimination charger.

In addition, as shown in FIG. 3, it is preferable that the outer peripheral part of the carrier catch macro roll 22 is formed of an elastic member 30 or covered with an elastic member 30.

. If you do it like 2, carrier catch macro roll 22
Since the carrier can be brought into close contact with the photoreceptor drum 2, the carrier that has fallen onto the photoreceptor tram 2 can be reliably attracted and recovered.

■ As explained above, the present invention is capable of adsorbing the cleaning agent separated from the magnetic brush forming member, etc. by the magnetic roll provided between the magnetic brush forming member and the static elimination charger. Therefore, it is possible to prevent the magnetic carrier material from adhering to the static elimination charger, thereby preventing leakage and deterioration of the static elimination effect, thereby improving the reliability of cleaning.

[Brief explanation of the drawing]

FIG. 1 is a block diagram schematically showing an example of a conventional magnetic plasticening device. FIG. 2 is a block diagram schematically showing an embodiment of the present invention. FIG. FIG. 7 is a diagram schematically showing only the main parts of another embodiment. 1.20 Magnetic brush cleaning device 2 Photoconductor tram 6 Static neutralization charger S Cleaning sleeve (magnetic brush forming member) 14.1-Toner collection roller (toner collection member) 22 Carrier catch Macroll (magnetic roll) 25・Plate 27・Screw con・＼Ashi 8・
・Exhaust passage 2nd・・Exhaust fan 30・・Elastic member Fig. 1 Fig. 2

Claims (1)

[Scope of Claims] 1. Disposed adjacent to the photoreceptor and following the static elimination charger, it magnetically attracts the cleaning agent to form a magnetic brush and captures untransferred toner remaining on the surface of the photoreceptor. a magnetic brush forming member, a means for separating and shielding the cleaning agent from the magnetic brush forming member, and disposed in a circulation path thereof. In the magnetic brush cleaning device, the magnetic brush cleaning device includes a toner collection member for collecting toner adhering to the cleaning agent. 2. A magnetic roll that adsorbs the cleaning agent removed from the magnetic brush forming member, etc. between the forming member and the static elimination charger; A magnetic brush cleaning device comprising: a cleaning agent recovery means for recovering the cleaning agent adsorbed on the magnetic roll.