JPS6244786A - Cleaning device - Google Patents

Abstract

PURPOSE:To clean the surface of an image carrier excellently without scattering magnetic powder such as toner by providing a magnet to an end part of a developing roller which conveys a developer in a developing device which uses the magnetic powder as the developer. CONSTITUTION:Toner scraped off with a blade 12 falls on the peripheral surface of a rubbing roller 11 and is conveyed to the side of a conveyor screw 15 through the rotation of the roller 11, scraped off the roller peripheral surface 11a by a scraper 14, and discharged to the outside by the conveyor screw 15. In this case, residual toner does not stick only on the rubbing roller 11 and moves to the rubbing roller end part 11d to fall off the rubbing roller 11, so that it sticks on magnet roller 19a and 19b at end parts. The residual sticking toner is scraped off the peripheral surfaces of the magnet rollers by a scraper 20 for the magnet rollers and is discharged by the conveyor screw 15.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] In the image forming apparatus VC of the present invention, developer, dust, corona products, etc. attached to the overlapping IJ-coating surface are removed from the surface to be cleaned. The present invention relates to a cleaning device. This cleaning device is related to a cleaning device K for an image bearing member of an electrophotographic device, a recording device, or the like. The objects to be cleaned include well-known electrophotographic photoreceptors, insulators capable of retaining electrostatic latent images, and magnetic materials capable of retaining magnetic latent images, and conventional magnetic powder is used as the developer. Reminders are valid.

[Prior art]

Conventionally, an electrostatic photographic process has been used in a nine-iron forming apparatus that uses a plurality of corona emitters for the purpose of charging an image carrier, transferring a toner image to a transfer member, etc. ! Generally, the surface of the image carrier is charged with a device. Therefore, molecules in the air change due to corona discharge, and substances such as nitrogen oxides may be generated.

These corona products adhere to the surface of the image carrier, and in a high humidity environment, the resistance of the surface of the image carrier decreases, blurring the electrostatic latent image formed on the surface of the image carrier, etc. There are times when it casts an evil influence.

Conventionally, in order to remove the above-mentioned adverse effects, image bearing members have been heated and dried, or by arranging a so-called cleaning blade and rotating a rubbing roller made of silicone rubber or the like against the surface of the image bearing member. Methods such as rubbing the body surface to remove corona products have been proposed.

In particular, the latter method is effective because it is stable even when the image carrier is used for a long period of time, and it also prevents substances in the transfer member such as paper from adhering to the surface of the image carrier, and toner from being fused to the surface of the image carrier. (It is also effective in removing cases where it occurs), and is an excellent northern method.

Here, the residual toner that has been removed from the photoconductor by the cleaning blade is passed on the rubbing roller, scraped off by the system flavorer, and discharged by the screw, but during this process, the toner floats in the cleaning device, and the cleaning device Splashing outside was occurring. One possible method to reduce this scattering is to make the length of the cleaning blade and rubbing roller sufficiently long for the image area, but in practice this is due to demands such as miniaturization of the device. It is often impossible to make it long enough. Therefore, please note that there are still some difficulties with the above measures against scattering.

[Purpose of the invention]

An object of the present invention is to provide a cleaning device that prevents powder developer (hereinafter referred to as toner) from scattering to the outside. Yet another object of the present invention is to provide a compact leaning performance device. A further object of the present invention is to provide a cleaning/cleaning device that can provide a good cleaning performance.

[Ninth configuration for achieving the above object] The present invention is advantageous in that a magnet is provided at the end of a developing roller used to convey the developer in a developing device that uses magnetic powder as a developer.

〔Example〕

The present invention will be explained in more detail according to examples.

FIG. 1 is an explanatory diagram of the main parts of an electrophotographic copying apparatus to which all of the cleaning apparatuses according to the embodiments of the present invention are applied.

The figure shows an example of a 1F'i image carrier in which a photoreceptor 1a as an electrostatic image carrier having a photoconductive material such as S.theta., OPO or a-8i is supported in the form of a drum. This drum-shaped image carrier 1 is pivotally supported by a shaft 1b and rotates in the direction indicated by the arrow. Further, 2 is a corona discharger which uniformly charges the surface of the photoreceptor 1a with eζ. Reference numeral 3 denotes an optical means such as a short focus optical element array, which irradiates the photoreceptor 1a with a light image corresponding to the original image.

Furthermore, a developing device 4 (using a magnetic developer) develops a latent electromagnetic image formed on the photoreceptor 1a in response to irradiation with a light image. Note that the 4aFi magnet roller 4b is a scraper that restricts the standing of the ears on the roller 4a. Reference numeral 5 denotes a pair of timing rollers that serve to feed the transfer material P fed from a feeding means (not shown) to the transfer position in synchronization with the development on the photoreceptor 1a. 6 is a transfer material guide, and 7 is a transfer corona discharger, which applies a transfer corona that is opposite to the toner to the back side of the transfer material P, and transfers the toner image to the transfer material P fed into the transfer position 7a. to do. Further, 9 is a conveyor belt that guides the transfer material P after the transfer is completed to a fixing means (not shown);
゜ is a cleaning/f device based on an embodiment of the present invention. First, a toner image is transferred onto the transfer material P and the nine photoreceptors 1a
Fi, this cleaning = Et4i 1 D K Substances that cause image blur that adhere to the surface and are rubbed by the slider 11 (made of silicone rubber, urethane rubber, etc.) with a fixed bearing provided. ) is removed.

Thereafter, as the photoreceptor 1a rotates, the cleaning blade 12 removes the residual toner. Thereafter, the residual charge is removed by pre-exposure 13, and the process moves on to the next cycle. Note that the rubbing roller 11#i is installed in contact with the photoreceptor 1a, and its rotation direction and speed are the same as the photoreceptor 10 rotation direction and speed i.
In the illustrated embodiment, the directions of rotation of the two are reversed.

Further, numeral 14 in the figure is a scraper for removing toner and the like adhering to the surface of the rubbing row 211. 15 more
This is a feed screw that discharges residual toner, paper dust, etc. accumulated in the cleaning nozzle 10a to the outside of the cleaning nozzle 10.

Next, the cleaning device of this embodiment will be described in detail with reference to FIGS. 2, 3, and 4.

In the figure, with respect to the rotation direction A of the photoreceptor drum 1a,
A rubbing cleaning device 11 is provided upstream of the blade 12. This sliding row 211 is made of an elastic material such as silicone rubber or urethane rubber, and its peripheral surface 11a is in contact with the peripheral surface of the drum 1a. The rotary shaft 11C of the sliding roller 11 shown in FIG. 2 is rotatably held by bearings 16 at both ends 11b. Therefore, the roller 11 is connected to the side plate 1ob by the shaft 11G.
A motor M is rotatably attached to the
The drive wJ from the motor M is rotated by the gear train 18 from the motor M.

Note that the bearing 16 is provided on the side plate 101 of the housing 10a. Further, although the rotation direction of the roller 11 can be selected as appropriate, in this embodiment, the rotation direction of the drum 1 (arrow A
) and reverse rotation (arrow B).

t+, the length in the longitudinal direction of this roller 11 is the length of the photoreceptor 1a
Image area where Kii1j image is formed (Fig. 2, arrow C)
almost equal to

Both ends 11 of this roller 11 (LK is the shaft 11
0 K is maintained and magnetic rollers 19a-b are provided. The magnet rollers 19a-b have smaller diameters than the roller 110, and are provided facing outside the image forming area of the photoreceptor 1a. That is, the magnet rows 219a-b are attached to the end portion 11d of the roller 11 with adhesive, and the shaft 110K is fixed between the end portion 11 (1) and the bearing 160.

Therefore, as the shaft 110 rotates, the rubbing roller 11 and the magnet rollers 19a-b rotate together.

Nine, the scraper 20 is provided in contact with the entire circumferential width of the magnetic rollers 19a and 19b, and
Scrape off the toner adhering to the surfaces of 9a and b. These 20 scrapers and the scraper 14 are also arranged above.

Further, in the cleaning device 10, a cleaner/
A blade 12 is provided. The cleaning blade 12 is made of an elastic material such as urethane rubber or plastic. The tip end side 12a that contacts the photoreceptor 1a is approximately at a right angle. Further, the rear end side 12b of this blade 12 is attached to a part 10 of the blade holder provided in the cleaning housing 10a. It is held in place by adhesive. Note that the cleaning blade 12 is in contact with the photoreceptor 1a with its tip facing the rotational direction of the photoreceptor 1a. Note that 10C is a felt sealing plate that can prevent the developer from scattering to the outside through a gap with the photoreceptor surface.

Next, the operation of the cleaning device of this embodiment will be explained.

After the toner image formed on the photoreceptor 1a is transferred onto the transfer material P, the photoreceptor 1a with residual toner attached is first rubbed by the circumferential surface 11aK of the rubbing roller 11. Therefore, due to the rubbing of the roller 11, a certain amount of the residual toner is removed from the photoreceptor 1a, and the remaining toner is removed from the photoreceptor 1a.
Corona products, paper powder, fused toner, etc. that have adhered to the photoreceptor 1a are scraped off by the roller 11. Then, the remaining toner passes through the contact area between the row 211 and the photoreceptor 1a while adhering to the photoreceptor 1a (normally, the amount of toner passing through the contact area is greater than the amount of toner scraped off by the rubbing roller). 1 is more common), Cree Ni/Gblade 1
2, the top of the photoreceptor 1a is scraped off. Then, the toner is scraped off by the blade 12, and the rubbing roller 11
It falls onto the circumferential surface 11a of the roller 11, is conveyed to the conveying screw 15 side by the rotation of the roller 11, is scraped off from above the roller circumferential surface 11a by the scraper 14, and is discharged to the outside by the conveying screw 15. At this time, the residual toner does not adhere only on the rubbing roller 211, but rather on the rubbing roller end 11d.
The particles move to the side, fall off the rubbing roller 11, and adhere to the magnetic rollers 19a and 191) at the ends. This adhered residual toner is scraped off from the surface of the magnet roller by the scraper 20 for the magnet draw 2.
It is discharged by the conveying screw 15.

Further, the residual toner that has moved to the outside of the image area along the edge of the cleaning blade 12 falls to the lower part of the blade due to gravity, but this residual toner is also scattered outside in a thin film by the magnet rows 219a and 19m). Never. Furthermore, even if the toner floating inside the housing Ioa tries to leak out of the device, it will be collected on the circumferential surface of the row 2 by the magnetic force of the magnet rollers 19a and 19b, so that the toner will not scatter to the outside. There's nothing to do.

Next, the above-mentioned scrapers 14 and 20 will be explained in detail.

Note that the scraper 14 for the rubbing roller 211 is required to have at least the length of the rubbing roller 11, and the length of the scraper 14 for the rubbing roller 211 is at least the same as the length of the scraping roller 11.
Similarly, the length of the scraper 20 is also required.

Here, the outer shape d1 of the rubbing roller 11 and the magnets 19L and 19
The relationship between b and the outer diameter d2 must be at least dl>d2.
In some cases, a dedicated scraper 14 can be used for both purposes. In other words, if only (d+ - d2)/2 spikes of toner are allowed, the height of the spikes of toner can be reduced by extending the length of the scraper 14 for the rubbing roller to the magnet part. It is possible to cut the part with a height of (d+ -42)/2 or more. Note that in this example, the magnetic field (
In this case, the magnetic developer includes a two-component developer consisting of a magnetic carrier such as powder and a b-type toner, or a one-component developer consisting only of a magnetic carrier. Further, the present invention is not limited to a magnetic roller, and any suitable shape can be used as long as it is a magnet.

[Other Examples]

Next, other embodiments of the cleaning blade that can be applied to the cleaning device will be described. Figure 5 shows
FIG. 3 is a cross-sectional view of an embodiment of the cleaning blade.

In this example, in order to scrape off the toner effectively with the blade 25 and to prevent the photoreceptor 1a and the blade 23 from being worn out, the pressure with which the blade 23 is pressed against the photoreceptor 1a is appropriately limited. There is. That is, the blade 23 is biased counterclockwise around the shaft 26 by the weight of the weight 28 to press it into contact with the photoreceptor 1a.

In order to maintain uniform contact pressure by bringing the blade 25 into contact with the photoreceptor 1a in a state aligned with the direction of the rotational axis, a so-called equalization method is adopted in which the blade 23 rotates about the shaft 27. Note that 28 and 29 are blade attachment parts.

When a newly developed equalization type blade is used as in this embodiment, it may not be possible to install the housing sufficiently close to the photoconductor. However, if the present invention is used, toner can prevent scattering.

Next, a specific example of a cleaning device using the above embodiment will be described.

As the rubbing roller, one made of silicone rubber or urethane rubber is used, and the circumferential speed of the photoreceptor drum is approximately 1 aof.
i,/s, 60%~80ts or 120~
Rotate at a circumferential speed of about 140% & (lffff The roller was rotated counterclockwise with respect to the drum rotating in the direction of the meat)
. The diameter of this rubbing roller was approximately 20 mm, and the length was 307 mm. Furthermore, magnetic rollers having a diameter of about 18 mm and a length of about 12 mm were provided coaxially with the roller at both ends of the roller. Note that the strength of the magnet of this magnetic roller was approximately 800 to 1600 Gauss. Also,
As a scraper for the rubbing roller, the thickness is approximately o, o5.
A stainless steel plate with a thickness of 0.2 mg or a polyester sheet with a thickness of about 0.2 FIl11 was used. A polyester sheet having a thickness of 0.2 to 0.31111 mm was used as a scraper for the magnet roller.

By using a cleaning device with such a configuration,
The surface of not only a conventional photoreceptor but also an amorphous silicone photoreceptor could be cleaned well, and no toner was scattered outside the cleaning device.

[Effects of the Invention] As described above, the present invention provides a cleaning device that can properly clean the surface of an image carrier without causing scattering of magnetic powder such as toner. be.

[Brief explanation of drawings]

FIG. 1 is an explanatory view of the main parts of an electrophotographic copying machine to which a cleaning device according to an embodiment of the present invention is applied, FIG. 2 is a plan sectional view of the main parts of the cleaning device, WJs is a side sectional view thereof, and FIG. The figure is a perspective view of a cleaning device using an embodiment of the present invention, and FIG. 5 is a side sectional view of another embodiment of the cleaning blade. In the figure, 1a is a photosensitive drum, which is an example of an image carrier;
0 is cleaning equipment, 1oa Fi housing, 1
1 is a rubbing cleaning roller, 12 is a blade, 19a
・1qbti magnet roller is shown. qri

Claims (1)

[Claims] (1) A cleaning device for cleaning a surface to be cleaned, which includes a cleaning member that comes into contact with the surface to be cleaned in order to clean the surface to be cleaned, and a receiver for receiving magnetic powder removed from the surface to be cleaned by the cleaning member. A cleaning device comprising: means; and magnets provided at both ends of the cleaning member to prevent magnetic powder removed from the surface to be cleaned by the cleaning member from scattering to the outside.