JPS59193482A - Magnetic cleaning device - Google Patents

Abstract

PURPOSE:To raise cleaning efficiency by vibrating in an axial direction a non- magnetic sleeve which incorporates a magnet roll and is provided with a cleaning brush. CONSTITUTION:The non-magnetic sleeve 11 which incorporates a rotary magnet roll 10 and is provided with a cleaning brush 22 contacting with a photosensitive drum 1 executes the reciprocating vibration in the axial direction by the projecting part 20 of the roll 10, the fixed projection 19 of a flange 14 of the sleeve 11, and a reset spring 18. In this state, a surplus residual toner 23 of the drum 1 is cleaned efficiently by the brush 22 vibrated as one body, moved on the sleeve 11 through the roller 10 and collected to raise the cleaning efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION The present Bimei relates to a magnetic cleaning device, and in particular, uses magnetic toner to clean an electrostatic latent image formed on the surface of a carrier such as a selenium drum using techniques such as electrophotography or electrostatic recording. The present invention relates to a magnetic cleaning device used in a copying machine which, after developing and forming a toner image, transfers the toner image onto a transfer section of general paper or the like by corona discharge or the like to obtain a recorded copy.

In general, methods for making copies on general paper using magnetic toners do not require toner absorption control compared to conventional two-component developer systems that use a mixture of non-magnetic toner and carrier iron powder. Since it is possible to create a compact current device and has many advantages such as maintenance free and improved reliability, it is often used in electronic copying machines, printers, etc.

Such copying systems often have a configuration roughly as shown in FIG.

Here, FIG. 1 is a schematic diagram showing the copying process.

After a drum 1 having a photoreceptor layer such as a relen rotating in the six directions of the arrow is uniformly charged by a corona discharger 2, the photoreceptor layer is irradiated with light by an exposure device 3 to remove the electrostatic latent. An image is formed, and then a magnetic toner is electrostatically attached to the latent image surface using a carrier 4 to make it visible.This developing machine generally performs magnetic brush development using a magnet 1 to a roll. It is true.

The magnetic toner image on the drum 1 after development is transferred to a corona charger 5.
By applying an electric field from the back side of the transfer paper 6, electrostatic transfer is performed onto the transfer paper 6''. There are other transfer methods, such as using a conductive rubber roller, but no matter what transfer method is used, the amount of magnetic 1 hener transferred is not 1.00%, but is usually around 10%. When the transfer efficiency decreases, especially at high humidity, more than 40% of the 1-G untransferred magnetic 1-toner remains on the drum.

Therefore, in order to continuously carry out the copying process, it is necessary to use the cleaning device 7 to remove the remaining magnetic toner. In order to perform this cleaning more effectively, the residual charge on the ram 1 is often removed using the AC corona discharger ε3 or exposure means before refreening.

Cleaning device-C is a conventional cleaning device that uses a fur brush made of rabbit hair or synthetic fiber hair that rotates at high speed to wipe the drum surface, sucks up the removed dirt with a large suction device, and collects it in a noil tarbag. Type 6 is the most commonly used. However, this method (1) requires a large space due to its large size, and since the drum surface is rubbed at high speed, the drum becomes fatigued quickly, and unsuctioned toner scatters and contaminates the copying machine. There are drawbacks that cause inconvenience.

An alternative method is to use the magnetic properties of toner to rotate a magnet roll and a non-magnetic sleeve relative to each other, and use a magnetic brush to generate magnetic toner that has been previously attracted to the non-magnetic sleeve. A method of cleaning by rubbing the top has also been adopted, but it requires 1 hener to form a magnetic brush on the non-magnetic sleeve in advance, and the residual potential on the drum is high, resulting in the same effect as re-plating. In order to increase the cleaning efficiency, a strong magnetic force of 1000 G or more is required on the non-magnetic sleeve, and the distance between the drum and the non-magnetic sleeve and the thickness of the 1 henna layer on the non-1A '141 sleeve must be adjusted. There are many disadvantages such as the need for precise adjustment of the toner and the difficulty in recovering toner cleaned from the drum from the non-magnetic sleeve.

The present invention solves the above-mentioned drawbacks and has the object of providing a magnetic cleaning device capable of increasing cleaning efficiency without damaging the image carrier surface.

The structure of the present invention is such that a non-magnetic sleeve is installed facing the image carrier surface, a permanent magnet member having a plurality of magnetic poles is rotatably installed in the sleeve, and the sleeve is placed opposite the image carrier surface. A cleaning brush in contact with the image carrier surface is provided in the section, and the permanent magnet member is rotated. The reason is that the magnetic cleaning device vibrates the sleeve in the axial direction.

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

Here, FIG. 2 is a schematic sectional view of a magnetic cleaning device according to an embodiment, and FIG. 3 is a sectional view taken along line XX in FIG. 2, which corresponds to the cleaning device 7 in FIG. 1.

In the figure, 10 is a magnet 1 which is a permanent magnet member.
11 is a non-magnetic sleeve.

The magnet roll 10 has a structure in which magnets 1 to 12 having eight magnetic poles are fixed to a shaft 13. The non-magnetic sleeve 11 is placed on the outer periphery of the flange 14, 14' facing the drum 1 at a constant distance.

Moreover, the magnet roll 10 has a shaft 13 connected to a flange 14.
．． By inserting it into the inner hole 14' via bearings 15, 15', it is rotatably taken in the non-magnetic sleeve 11 and rotated in the direction of arrow B.

16 is a side plate to which the magnet roll 10 is attached, and has a bearing 17, and the shaft 13 rotatably attached to the flange 14 is rotatably attached to the bearing 17. There are gaps between the flange 14 and the side plate 1G and between the flange 14 and the magnet roll 10, and a spring 18 is interposed on the shaft 13 between the flange 14 and the side plate 16. M1=
A protrusion 19.20 is fixed between the flange 14 and the magnet roll 10 at a position that engages the flange 14d5 and the magnet 12 when they are rotated. The protrusions 19,20 may be provided at one or more locations. Further, the narrow end side of the flange 14' is supported by the side plate 16' via a bearing 17'.
Furthermore, a spacer 2 is provided between the side plate 16' and the flange 14'.
1 is interposed.

A cleaning brush 22 is fixed to the sleeve 11 and is provided in a portion of the drum 1 facing the image carrier surface so as to be in contact with the drum. Reference numeral 23 indicates untransferred residual magnetic toner that has adhered to the tram 1, 24 indicates a scraper that scrapes off the residual magnetic toner 23, and 25 indicates a container that accommodates the scraped off magnetic toner.

In the above construction, when the magnet roll 10 rotates, the protrusion 20 fixed to the magnet 12 and one protrusion fixed to the 7 flange 14 engage with each other, so each time they engage, the flange 14 move in the direction. Protrusion 1
When the positions of 9 and 20 are shifted and the engagement is released, the flange 14 moves in the direction of the arrow due to the restoring force of the spring 18. The frequency of this flange 14 is the number of rotations of the magnet roll x
This is the number of protrusions installed. 7. In accordance with the vibration of the flange 14, the sleeve 11 fixed to the flange 14 also vibrates, so that the cleaning brush 22 wrapped around the sleeve 11 also vibrates in the axial direction.

The cleaning brush 22 is provided in contact with the drum 1 at a portion facing the image carrier surface of the drum 1, so that it rubs the surface of the drum 1.

At this time, the drum 1 that has completed the transfer rotates in the direction of the arrow.
c Close to the non-magnetic sleeve 11.

The particles then reach the cleaning brush 22 that is rubbing the surface of the drum 1, and are reliably removed by the rubbing vibrations of the cleaning brush 22. In addition, since the cleaning brush 22 does not rotate because the non-magnetic sleeve 11 does not rotate, it is possible to reduce damage to the surface of the drum 1.

In this case, the height of the cleaning brush 22 is 0.5~
The range is preferably 5 mm, preferably 3 to 511 m.

If it is less than 0.5 mm, the cleaning effect will be low, and if it is less than 5 mm,
71 is 1 - The surface of ram 1 is damaged.

And as for the cleaning brush, it's 47 meters long. Since the J1 mountain in A has a static eliminating effect, the adhesion force of the groove to the photoreceptor is weakened and the cleaning performance is improved.

The magnetic toner 23 that has adhered to the cleaning brush 22 is attracted onto the non-magnetic sleeve 11 by the magnetic attraction force of the magnet, and is then conveyed in the direction of arrow F by the rotation of the magnet roll 10 in the direction of arrow B. It is scraped off by the scraper 24 and collected into the container 25. In this case, the magnetic force of the magnet 1-12 is
1 and 500G or more is sufficient. The frequency of the non-magnetic sleeve 11 may be 1.5 times/380 or more, and preferably 5 times/sec or more.

Specific example 1 - Ram 1, peripheral speed 150 mm/sec, outer diameter 120
Using a 3e drum of n1mφ, non-magnetic sleeve 11,
A stainless steel material with an outer diameter of 32 mm is used, the gap with the drum 1 is 3 nv, and the frequency of the non-magnetic sleeve is set to 10 times/
sec doshi1 [. Magnet 12 has an outer diameter of 29mmφ
A Ba ferrite magnet is used, 8 poles are symmetrically magnetized, the magnetic force on the non-magnetic sleeve 11 is 800G, and the rotation speed is 30Q.
rpm. Further, the height of the cleaning brush 22 was set to 4 mm, and the width was set to 10 mm.

Based on the above specifications, the drum 1 was able to be bound to remove residual magnetism from 1 to 1, and to perform good leaning.

As described above, the present invention provides a non-magnetic sleeve that is disposed opposite to the image carrier surface, a permanent abutment section having a plurality of magnetic poles within the sleeve, and a non-magnetic sleeve that is rotatably disposed within the sleeve. A cleaning brush that is in contact with the image carrier surface is provided on the opposite side of the image carrier surface, and the cleaning brush is cleaned by vibrating the sleeve in the axial direction while rotating the permanent magnet part. By rubbing, residual magnetic 1-ner adhering to the surface of the image carrier can be effectively removed.

[Brief explanation of drawings]

Figure 1 is a strategic side view showing the copying process; Figure 2 is a strategic side view showing the copying process;
FIG. 3 is a schematic sectional view of a magnetic cleaning device according to an embodiment of the present invention, and is a sectional view taken along line XX in FIG. 2. 1...Drum, 10...Magnet roll, 11.
...Non-magnetic sleeve, 12...Magnet, 13...
・Shaft, 22...Cleaning brush. Patent Applicant Hitachi Metals Co., Ltd. Agent 1st Figure 2 Figure 3 ゛17, - ~

Claims (1)

[Claims] A non-magnetic sleeve is installed opposite to the image carrier surface, a permanent magnet section 4A having a plurality of magnetic poles is rotatably installed in the sleeve, and the image carrier is placed in a portion of the sleeve facing the image carrier surface. Install a cleaning brush that comes into contact with the surface (
), a magnetic cleaning device characterized in that the sleeve is vibrated in the axial direction while rotating the permanent magnet member.