JPH03206486A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent inferior cleaning which occurs because of the sticking of toner due to generated static electricity and the mulfunction, etc., of a device caused by the occurrence of an electric noise by using a metallic thin plate which is a conductor electrically for a toner guide member. CONSTITUTION:The toner guide member 15 which is attached to one end of a rocking member 16 supported by a rotary supporting shaft 17 which is under the bottom surface of a cleaning device housing 11 and where a developer receiving part 14 faces to a photosensitive drum 100 side is provided on an upstream side in a rotational direction from a blade member on the peripheral surface of the photosensitive drum 100. The metallic thin plate whose thickness is 0.02mm-0.08mm is used as the toner guide member 15, whose length is nearly equal to the width of the photosensitive drum 100 and which is bonded to the one end of the rocking member 16. The rocking member 16 is also constituted of the metallic material which is the conductor, electrically. Then, the toner guide member 15 and the rocking member 16 are perfectly electrically grounded by electrically grounding from the one end of the rocking member 16 through a lead wire 19, etc. Thus, the sticking of the residual toner caused by the generated static electricity and the mulfunction caused by the occurrence of the noise are eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a cleaning device for removing residual toner adhering to the surface of an image bearing member of an electrostatic recording device.

[Conventional technology]

In electrostatic recording devices, a rotating photoreceptor drum is generally used as an image carrier, and after the toner image formed on the circumferential surface of the drum is transferred to a transfer medium, the residual toner is removed by static eliminating means. After that, the surface of the photoreceptor is cleaned by being removed by a cleaning means in a cleaning device. The residual toner removed by the cleaning means is
It is collected outside the cleaning device by a conveyance means.

Therefore, the cleaning device is provided with a blade member that serves as a cleaning means for removing residual toner and presses against the surface of the photoreceptor drum, and a screw member that collects the toner, conveys it in one direction, and accumulates it. They are housed in a cleaning case to prevent toner from scattering and are placed facing the surface of the photoreceptor drum.

However, due to the layout of the image forming equipment surrounding the photoreceptor drum, the cleaning device is often placed almost right next to the photoreceptor drum. There is a high risk that toner will fall into the recording device from a small gap, or
; Accumulated inside the cleaning case! Above all, they tended to accumulate locally, significantly reducing the efficiency of recovery.

In such a cleaning device, the toner guide member is made of, for example, polyethylene terephthalate (PET).
A scraper made of a resin material such as a thin film-like plate is used, one end of which is fixed to the cleaning device housing, and the other end is pressed against the circumferential surface of the photoreceptor drum. The toner scraped off by the blade member located in the toner falls along the inclined scraper and is sent directly to the conveying screw. This is similar to the proposal made in, for example, Japanese Unexamined Patent Publication No. 55-120069.

Alternatively, the peripheral surface of the photoconductor drum is brought into pressure contact with a rotation receiving sponge roller that rotates at a position corresponding to the toner guide member with respect to the photoconductor drum, and the toner scraped off by the blade member is transferred to the rotation receiving sponge roller. There is also a cleaning device in which the sponge is conveyed by the rotation of the sponge roller and then fed into a conveying screw along the inclined surface of a scraper that presses against the sponge roller.

[Problem to be solved by the invention]

All of these scrapers have a long length corresponding to the width of the photoreceptor drum, so it is difficult to maintain an even contact pressure by keeping the ridge line straight. ) Resin materials such as 7-ilm are electrically insulating, and there is a limit to their elastic contact force. In addition, the toner guide member is bonded to the metal support member with double-sided adhesive tape, which tends to generate static electricity, which can cause residual toner to adhere to the scraper and impede toner conveyance, and noise to cause electrostatic recording. This may cause the electronic control of the entire device to malfunction.

Furthermore, the difference in thermal expansion coefficient due to temperature changes between the resin scraper and the metal support member has a large effect, and in extreme cases, the scraper becomes wavy and cannot be evenly pressed against the circumferential surface of the photoreceptor drum, creating a gap. This may cause toner leakage. and,
There is also a risk of damaging the surface of the photoreceptor drum. On the other hand, if the pressure contact force of the scraper is too strong in some areas, there are problems such as residual toner on the surface of the photoreceptor drum falling when passing through the scraper and leaking out of the cleaning device.

Incidentally, although the rotating receiving roller type has good accuracy, it has problems such as a complicated structure and high equipment cost.

[Means to solve the problem]

The present invention has been made for the purpose of solving the above-mentioned problems, and it is an object of the present invention to electrically ground the toner collection member by improving the toner guide member, thereby preventing the generation of static electricity and noise. Another object of the present invention is to equalize the pressing force on the surface of the photoreceptor drum to eliminate problems caused by toner leakage and the occurrence of scratches on the photoreceptor drum.

A cleaning device according to the present invention that achieves the above object includes a cleaning device for cleaning residual toner adhering to the surface of a rotating image carrier with a cleaning member, the cleaning device cleaning the residual toner adhering to the surface of a rotating image carrier. A toner guide member located on the more upstream side, one end of which is in contact with the image carrier, receives the residual toner removed by the cleaning member and guides it to the toner collection member, is formed of an elastic thin metal plate, and This is characterized in that the toner guide member is electrically grounded.

〔Example〕

FIG. 1 is a sectional view of a main part of an image forming section of an electrostatic recording apparatus equipped with a cleaning device of the present invention. FIG. 2 is an enlarged sectional view of the cleaning device according to the present invention, and FIG. 3 is a perspective view of the toner guide member.

When the copying operation is started, the photosensitive drum 100 carrying the electrostatic image begins to rotate in the direction of the arrow, and after first applying a uniform charge to its surface by the charging electrode l, the original image is transferred to the exposure section 2. When exposed to light, an electrostatic latent image is formed.

Subsequently, the electrostatic latent image is visualized by the developing action of the developing device 3 to become a toner image, and the toner image is transferred onto the recording paper fed from the conveying path 4 by the transfer pole 5. The recording paper that has undergone the transfer is transferred to the photosensitive drum 1 by the separation pole 6.
It is separated from the circumferential surface of 00, conveyed by a conveyor belt, and after the image is fused by a fixing device (not shown), it is discharged from the recording apparatus.

On the other hand, the photoreceptor drum 100 from which the recording paper has been separated continues to rotate in the direction of the arrow, and reaches the cleaning device IO of the present invention, which is disposed at a position directly beside the photoreceptor drum 100, approximately corresponding to the horizontal axis plane. After the residual toner on the peripheral surface is peeled off and cleaned by the cleaning action, the next rotation cycle is started and the image forming and transfer process is performed again.

The cleaning device 10 includes a cleaning device housing 1
1 is a container, and a blade member l2 as a cleaning member whose tip end is urged to come into pressure contact with the circumferential surface of the photoreceptor drum 100 at a position slightly above the horizontal plane is built therein, and the blade member l2 is a cleaning member. Below member l2,
A developer receiving portion l4 houses a screw l3 in a position where it can directly receive and contain most of the toner that is peeled off and falls.
It is equipped with

This screw 13 is driven to rotate and sends toner guided by a toner guide member l5, which will be described later, into the developer receiving portion l4.

Furthermore, on the upstream side in the rotational direction of the photosensitive drum 100 by the blade member, there is a cleaning device housing 11 facing the photosensitive drum 100 side of the developer receiving portion l4.
There is a toner guide member l5 of the present invention attached to one end of a swinging member l6 supported by a rotating support shaft l7 below the bottom surface of the toner guide member l5. FIG. 3 shows the details of this toner guide member l5, which includes a thin metal plate with a thickness of O-02 mm to 0.08 mm.
For example, a stainless steel plate, a tool steel plate, a beryllium steel plate, a phosphor bronze plate, or the like is used, and the length is approximately equal to the width of the photoreceptor drum 100.

The toner guide member l5 is integrally joined to one end of the swinging member l6. This swinging member l6 is also made of a metal material that is an electrical conductor.

The toner guide member l5 and the swinging member l6 may be joined by means such as conductive adhesive, conductive double-sided adhesive tape, metal riveting, spot welding, etc., and may be electrically connected. It is possible.

Furthermore, in the case of non-conductive bonding, it is necessary to electrically connect them to each other by wiring to make them conductive. Further, one end of the swinging member l6 is electrically grounded by a lead wire l9 or the like. Thus, the toner guide member 15 and the swinging member l6 are completely electrically grounded.

The swinging member l6 has holes 16a at both ends thereof held by a rotation support shaft l7, so that it can swing freely. The swinging member 1
A protrusion 16b is bent near the other end of the coil spring 16, and one end of a coil spring l8 is engaged therewith. The other end of the coil spring l8 is engaged with a protrusion 11a provided at the lower end of the cleaning device housing 11, and biases the swinging member l6 clockwise about the rotational shaft l7. As a result, the tip of the toner guide member l5 joined to one end of the swinging member l6 is pressed against the surface of the photoreceptor drum 100 uniformly with a predetermined pressing force. That is, due to the tension of the coil spring l8, the toner guide member l5 is uniformly pressed against the circumferential surface of the photoreceptor drum 100 with an appropriate pressure, and is scraped off by the blade member l2; can lead to. Since it is a thin metal plate, it does not deform in any way due to environmental changes such as temperature, and since the connection with the swinging member l6, which is a support, is also made of metal, it operates stably without any problems.

Examples of the thickness of the thin metal plate used for this toner guide member l5 and the effect of the toner guide are shown in [Table 1].

[Table 1] From the above results, it can be seen that when the thickness of the metal thin plate is 10 μm, it is thin and easily breaks, and when it is 100 pm or more, the rigidity is high and the pressing force is strong, which is inappropriate, and a thickness of 20 μm to 20 μm is suitable.

In addition, regarding the effects of changes in temperature and humidity, we used the stainless steel thin plates shown in [Table 2] below. As a result of making 50,000 copies under conditions of 80% RH and 80°C, no problems occurred and the results were good.

From this result, it can be seen that there is no effect of temperature and humidity on the undulations and the like when conventional PET films are used.

Since this toner guide member l5 is grounded through the swinging member l6 as described above, even if the residual toner is charged, it does not adhere to the toner guide member l5, and the residual toner is effectively directed toward the screw 13. It can be transported. Furthermore, since no noise is generated, the electronic control system of the entire electrostatic recording apparatus will not malfunction.

〔Effect of the invention〕

The present invention has been developed by using an electrically conductive metal thin plate as a toner guide member instead of a scraper made of an insulator such as PET7 film, which has been conventionally used as a toner guide member in a cleaning device. It has been possible to eliminate poor cleaning caused by toner adhesion due to the generation of static electricity, as well as equipment malfunctions caused by electrical noise. Additionally, it completely prevents damage to the photoconductor drum and undulations of the toner guide member due to the effects of temperature, humidity, etc., and allows for efficient conveyance and recovery of residual toner on the circumference of the photoconductor drum. Now I can do it. In addition, since this toner guide member is a thin metal plate, it can be manufactured in one piece in a hollow shape, making it possible to provide a toner guide member with excellent flatness at a low cost, and making it possible to provide an electrostatic recording device that always operates stably. .

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of an image forming section equipped with a cleaning device according to the present invention, FIG. 2 is an enlarged sectional view of the cleaning device according to the present invention, and FIG. 3 is a perspective view of a toner guide member. 10... Cleaning device 11... Cleaning device housing l2... Blade member l3... Conveyance screw l4... Developer receiving portion l5... Toner guide member l6... Swinging member l8. ... Coil spring 100 ... Photosensitive drum (scraper) l7 ... Rotating shaft l9 ... Grounding lead wire

Claims (1)

[Claims] In a cleaning device that uses a cleaning member to clean residual toner adhering to the surface of a rotating image carrier, the cleaning member is located upstream of the cleaning member with respect to the moving direction of the image carrier, and one end is in contact with the image carrier. A cleaning device characterized in that a toner guide member that receives residual toner removed by the cleaning member and guides it to a toner collection member is formed of an elastic thin metal plate, and the toner guide member is electrically grounded. .