JPS6135475A - Cleaning device of electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To prevent securely toner from falling by setting the texture of sealing felt arranged at both ends of either of a cleaning blade and a developing blade in one direction as to the rotating direction of a drum. CONSTITUTION:Sealing felt 3 is arranged at both ends of the cleaning blade 2 which is arranged nearby and above the photosensitive drum 1. The cleaning blade 2 is so provided as to scrape toner 601 remaining on the surface of the photosensitive body 10 after a toner image is transferred and then be driven. A couple of sealing felts 3 each have one end supported and fixed at a fixation part and the other brought into contact with the surface of the drum photosensitive body 10, and the texture of the fiber of the sealing felts 3 is set in any one direction except sideway directions of the drum 1 about the turning direction of the drum 1. Consequently, the residual toner 601 on the surface of the photosensitive body 10 which is scraped off with the blade 2 is prevented securely from falling from side end parts of the blade 2.

Description

[Detailed description of the invention] (Technical field) The present invention relates to a cleaning device for an electrophotographic copying machine.

In particular, the present invention relates to a cleaning device that can prevent toner from falling from the cleaning blade side end and/or the developing sleeve side end.

(Conventional technology) around the photoreceptor drum for electrophotographic copying machines.

For example, a charging charger, an exposure means, a developing means, a transfer charger, a cleaning means, etc. are arranged in order along the rotational direction. The photoreceptor is charged by, for example, a charging charger, and then exposed to light by an exposure means to form an electrostatic latent image. Toner is applied to the photoreceptor by a developing means, for example, a magnetic brush formed on a sleeve, to form a toner image corresponding to the electrostatic latent image. The toner image is then electrostatically transferred to copy paper by a transfer charger. The copy paper onto which the toner image has been transferred is then fixed by a fixing means.

In the toner recycling system, untransferred toner remaining on the photoreceptor surface after transfer is once deposited and retained on the photoreceptor surface by a cleaning means such as a blade. This residual accumulated toner is then conveyed to the vicinity of the developing sleeve of the developing means together with the photoreceptor by separating the blade from the surface of the photoreceptor. Here, residual accumulated toner is removed from the surface of the photoreceptor by controlling the bias voltage applied between the developing sleeve and the photoreceptor drum.

In the cleaning process, the inside of the blade is set smaller than the developing device in order to collect toner with the developing sleeve. Therefore, the residual toner gradually accumulated on both ends of the blade wraps around the inside and outside of the blade and further into the inside and outside of the developing sleeve. As a result, this residual accumulated toner cannot be collected by the developing sleeve. This causes the transfer paper to become dirty. In order to prevent such collection of residual toner,
Alternatively, sealing felt may be applied to both ends of the developing sleeve. However, sealing felt usually uses natural animal hair or the like, and therefore, depending on its direction, it may have little effect on preventing toner from falling off. Due to such toner falling, the toner recovery rate becomes extremely low and the amount of toner consumed increases. In addition, the fallen toner scatters inside the copying machine and adheres to the surface of the photoreceptor, staining the toner image, and it also adheres to electrical and precision parts within the copying machine, causing it to interfere with the smooth operation of the copying machine. There is.

(Object of the Invention) The object of the present invention is to
Another object of the present invention is to provide a cleaning device for an electrophotographic copying machine that can reliably prevent toner from falling from the side end of a developing sleeve. Another object of the present invention is to provide a cleaning device for an electrophotographic copying machine that can keep the surface of a photoreceptor constantly clean, thereby forming good images.

Still another object of the present invention is to provide a cleaning device for an electrophotographic copying machine that can constantly keep the inside of the copying machine clean, thereby allowing the copying machine to operate stably over a long period of time. Yet another object of the present invention.

An object of the present invention is to provide a cleaning device for an electrophotographic copying machine having a simple configuration.

(Structure of the Invention) The cleaning device of the present invention is used, for example, in an electrophotographic copying machine using a toner recycling method. In the toner recycling method, first, toner remaining on the surface of the photoreceptor after toner transfer is scraped off with a cleaning blade. Then, by separating the blade from the photoreceptor surface,
The residual toner deposited on the surface of the photoreceptor is conveyed to the vicinity of the developing sleeve in the developing device as the photoreceptor drum rotates.

By controlling the bias voltage applied between the developing sleeve and the photoreceptor, the residual accumulated toner on the surface of the photoreceptor is moved onto the developing sleeve by electrostatic attraction and collected. Therefore, the cleaning device of the present invention has two components: a cleaning blade that is disposed near and above the photoreceptor drum and can be driven in the vertical direction; and a developing sleeve that is disposed near the drum and downstream of the cleaning blade. A sealing felt is provided at both ends of at least one of the drums, and the fibers of the sealing felt are oriented in at least one of all directions with respect to the rotational direction of the drum except for the side edge direction of the drum. , the above objective is achieved.

(Example) The present invention will be described below with reference to examples.

The cleaning device of the present invention is shown in FIG. 1 for example.

As shown in FIGS. 2 and 3, sealing felts 3 are provided at both ends of a cleaning blade 2 located near and above the photosensitive drum 1. The photoreceptor drum 1 has a photoreceptor 10 made of a photoconductive substance such as selenium on its outer peripheral surface.

The cleaning blade 2 is provided so that it can be driven upward after scraping off the toner 601 remaining on the surface of the photoreceptor 10 after the toner image has been transferred. The cleaning blade 2 is made of a material that does not damage the surface of the photoreceptor 10, for example, an elastic material such as rubber or synthetic resin such as polyurethane elastomer. The medium dimension of the blade 2 is not particularly limited, but is set to be smaller than that during normal development and larger than that of the transfer paper. Blade 2 is 2 e.g. 2
The sheets are arranged side by side at predetermined intervals.

Each of the pair of sealing felts 3 is supported and fixed at one end by a fixed portion, and is disposed such that the other end is in contact with the surface of the drum photoreceptor 10. The grain direction of the fibers of this sealing felt 3 is set in at least one of all directions except for the side end direction of the drum 1 with respect to the rotation direction of the drum 1. This reliably prevents the residual toner 601 on the surface of the photoreceptor 10 scraped off by the blade 2 from falling from the edge on the side of the blade 2. The shape of the sealing felt 3 is not particularly limited; for example, the side surface of the sealing felt 3 on the blade side has a dovetail shape. This sealing felt 3 is placed in close contact with the end of the blade 2 or with a predetermined gap therebetween. Seal felt 3
For example, wool or other animal hair is soaked in a hot soap solution or a hot sulfuric acid solution, and then compressed into a cloth shape. Felt made from synthetic fibers may also be used. The fiber length of the felt 3 is about 4 km or less, preferably 2 vA to 31 vA. It goes without saying that the higher the density of flocking, the better the prevention of toner falling off. On the back of Felt 3.

An elastic body such as a rubber plate can be coated as appropriate.

The sealing felt 3 may also be placed at both ends of the developing sleeve 61. Thereby, toner falling from the side end of the developing sleeve 61 can be reliably prevented.

The cleaning device of the present invention can be used for commercially available electrophotographic copying @ (D
C-211 (Sanda Kogyo type) was used to conduct an experiment to examine toner fall.

The grain direction 32 of the fibers of the sealing felt 3 used on the pointed base is as follows:
As shown in FIG. 3, this is the side direction of the blade 2 with respect to the drum rotation direction 11. This was placed at the end of the blade 2 with a gap of approximately 1.45 m to 1.61 m. As shown in FIG. 5, the manuscript 51 used in the experiment has solid black portions 52 at part of both side edges of the paper surface. This manuscript 51 was subjected to an acceleration copying test in a simulation mode (continuously repeating paper feeding and transfer) for 30 minutes. No toner fall was observed at all. The results are shown in the table below.

The grain direction 32 of the felt 3ta fiber for past armpit opening seal is shown in Fig.
The procedure is the same as in Experimental Example 1 except that the drums are aligned in the direction opposite to the drum rotation direction 11, as shown in FIG. No toner fall was observed at all. The results are shown in the table below.

The procedure was the same as in Experimental Example 1 except that the grain direction 32 of the felt fibers for the Oshunmasu Essile was aligned in the same direction as the drum rotation direction 11, as shown in Figure 3 (C1). Slight toner drop was observed. However, it did not affect the stable operation of the copying machine.The results are shown in the table below.

The grain direction 32 of the felt 3 fibers for disaster relief soil sealing is shown in Figure 3 (di
3 Experimental example 1 except that the drum was aligned in the same direction as the drum rotation direction 11 and tilted toward the blade 2 side, as shown in Figure 3.
It is similar to No toner fall was observed at all. The results are shown in the table below.

↓ As shown in FIG. 4, it is the same as Experimental Example 1 except that the grain direction 32 of the fibers of the sealing felt 301 is aligned toward the side edge of the drum 1 with respect to the drum rotation direction 1. It was observed that a large amount of toner fell over the sealing felt 301, and the sealing felt 301 was unable to achieve the effect of preventing toner from falling off. The results are shown in the table below.

(Margin below) (Effects of the Invention) According to the present invention, by setting the grain direction of the fibers of the sealing felt in a direction excluding the side edge direction of the drum with respect to the drum rotation direction, the cleaning blade side edge It is possible to reliably prevent toner from falling from the developing sleeve and/or the developing sleeve side end. As a result, the toner recovery rate increases and the amount of toner consumed decreases. Moreover, the surface of the photoreceptor is constantly kept clean, and good images can be provided.

Since the electrical parts and precision parts inside the copying machine are no longer contaminated due to toner dropout, the copying machine can operate stably for a long period of time. moreover.

Since it has a simple configuration, maintenance work can be performed extremely easily.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are a front sectional view and a plan view of a main part, respectively, showing an embodiment of the apparatus of the present invention. Fig. 3 (al to Fig. 3 fdl are respectively plan views of main parts showing embodiments of the device of the present invention, Fig. 4 is a plan view of main parts showing a comparative example of the embodiment of the device of the invention, and Fig. 5 is a plan view of main parts showing examples of the device of the present invention. 1 is a plan view showing an image paper used in an experimental example of the apparatus of the present invention. ■... Photosensitive drum, 2... Cleaning blade. 3, 301... Seal felt, 4, 7... Charger. 5...Optical system, 6...Developer, 8...Copy paper, 1
0... Photoreceptor, 11... Drum rotation direction, 32...
・Felt grain direction. 51... Original, 52... Solid black area, 60... Toner, 61... Developing sleeve, 62... Bias voltage, 601... Residual toner. that's all

Claims (1)

[Scope of Claims] 1. A cleaning blade disposed near and above the photoreceptor drum and capable of being driven in the vertical direction; and a developing sleeve disposed near the drum and downstream of the cleaning blade. an electrophotographic copying machine, comprising a sealing felt disposed at both ends of at least one of the sealing felt, wherein the grain direction of the fibers of the sealing felt is at least one of all directions other than the side edge direction of the drum with respect to the rotational direction of the drum. Machine cleaning equipment. 2. The fiber length of the sealing felt is approximately 2 mm.
3. A device according to claim 1, which is within the range of .about.3 mm. 3. The device according to claim 1, wherein the back surface of the sealing felt is made of an elastic material.