JPS6139080A - Cleaning mechanism of picture formation device - Google Patents

Abstract

PURPOSE:To reduce the titled cleaning mechanism in cost by arranging a cleaning means on a unit body so that cleaning around a scraping member can be executed in accordance with the loading/unloading of the unit body constituted so as to be optionally loaded/unloaded to/from a device body. CONSTITUTION:A roller 17b which is in contact with the picture transfer surface of transfer paper P is constituted so as to be charged and the scraping member 21 for scraping paper powder or the like of the transfer paper P which is adsorbed to the surface of the roller 17b is arranged in contact with the roller 17b. The cleaning means 26 for cleaning around the scraping member 21 in accordance with the loading/unloading of the unit body 25 constituted so as to be optionally loaded/unloaded to/from the device body 2 is arranged on the unit body 25. Consequently, paper powder or the like can be effectively removed from the transfer paper P before the carriage of the paper P to the transfer paper by an extremely simple and cost-reduced mechanism at the normal operation of a picture formation device 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an image forming apparatus such as an electronic copying machine, and more specifically, to an image forming apparatus such as an electronic copying machine, and more particularly, to an apparatus for transferring a toner image developed on a photoreceptor drum to a transfer paper. First, the present invention relates to a cleaning mechanism of an image forming apparatus for removing paper dust and the like adhering to the image transfer surface of transfer paper.

(B) Prior Art In image forming apparatuses such as electronic copying machines, transfer paper is generally used as a material for transferring a toner image developed on a photoreceptor drum. This transfer paper is made of fibrous material, and its surface contains a lot of fillers such as talc and clay, and paper dust is generated when cutting the transfer paper into regular sizes, so under normal conditions, There is some paper dust attached to the paper, but when it is transported from the paper feed section to the transfer section and then to the fixing section during copying, it may be due to friction between the sheets or frictional movement during the transport process by the transport mechanism. , an even larger amount of paper dust is generated, and these tend to adhere to the transfer surface of the transfer paper. Therefore, if transfer paper in such a state is used as is for transfer, not only will the toner image not be transferred properly onto the transfer paper, but paper dust, etc. may transfer and adhere to the photoreceptor surface of the photoreceptor drum. As a result, the photoreceptor on the photoreceptor drum deteriorates quickly, and during subsequent cleaning of the photoreceptor drum, paper dust and the like adhering to the surface of the photoreceptor are removed together with residual toner on the surface of the photoreceptor. In the method in which the residual toner removed by the toner is collected again in the developing device and reused, there is a drawback that not only the life of the toner is shortened, but also the toner cannot be reused.

Therefore, in order to eliminate the above-mentioned drawbacks, as a means to remove paper dust etc. from the transfer paper before it enters the transfer section, a method using a vacuum device or an electrostatic adsorption force using a charged insulated belt or roller is used. (Jikko 56-
50535, Japanese Unexamined Patent Publication No. 53-55128, and Japanese Utility Model Application No. 56-159357) have been proposed.

(7X) Problems to be Solved by the Invention By the way, although the vacuum device described above can almost completely remove paper dust, etc. from the transfer paper, the device is large-scale and expensive. In addition, in the case of using the electrostatic adsorption force of the insulating belt or roller, it is necessary to remove the paper powder adsorbed to the belt or roller, and for this purpose, scrapers and vacuums are required. A removal means such as a device is provided, which also has the problem of high cost.

(d) Means for Solving the Problems The present invention aims to solve the above-mentioned problems by configuring a roller located immediately before the transfer section and in contact with the image transfer surface of the transfer paper to be able to be charged. A roller is disposed in the main body 2 of the apparatus, and a scraping member for scraping paper dust etc. from the transfer paper adsorbed onto the roller is disposed in contact with the roller, and furthermore, at least a photosensitive drum or a developing member is disposed. The apparatus is characterized in that a cleaning means is disposed on the unit body so as to clean the vicinity of the scraping member as the unit body is moved in and out of the apparatus main body. be.

(f) Effect By employing the above means, the roller that comes into contact with the transfer paper on the image transfer surface is charged by the frictional action with the scraping member or by the charging means. Then, when the transfer paper is conveyed through rollers to transfer the developed toner image onto the photoreceptor drum,
Paper dust and the like on the transfer paper are removed from the surface of the transfer paper by the electrostatic adsorption action of the charged roller, and transferred and attached to the roller surface. In this way, the paper dust, etc. transferred and attached to the surface of the four-ra is scraped off by the scraping member as the roller rotates, and the roller surface is returned to a clean and charged state, and then rotated to the transfer paper to attract paper dust, etc. again. be contacted. When the unit body is pulled out from the main body of the apparatus periodically or as needed to replace the photosensitive drum or to replenish toner in the developing device, the cleaning means fixed to the unit body is also pulled out at the same time. Therefore, the paper dust and the like that have been scraped off by the scraping member and accumulated near the scraping member are brushed off to an appropriate location in the lower part of the device main body, and the area around the scraping member is restored to a clean state again.

(f) Example Hereinafter, embodiments embodying the present invention will be described.

As shown in FIG. 2, an image forming apparatus 1 such as a copying machine has a box-shaped apparatus main body 2, and on the top thereof is provided a document mounting table 3 made of a transparent member that moves back and forth in the direction of the arrow. , is provided with a paper feed section 5 on one side thereof, and further provided with a tray 6 on the other side for collecting the copied transfer sheets P. Inside the apparatus body 2, a photoreceptor drum 7, a charging device 9, a light source 10, an imaging element array 11, a developing device 1
20. An image forming means consisting of a transfer charging device 13, a cleaner device 14, a fixing device [15, etc.], and a pair of paper feed rollers 1
6, a transfer paper conveyance means consisting of a pair of registration rollers 17, a guide 19, a pair of paper discharge rollers 20, etc. are provided. Further, as shown in FIG. 1, the registration roller pair 17 is composed of a drive roller 17a and a driven roller 17b provided on the apparatus main body 2 side, and the driven roller 17b is made of an insulating material on a metal core, for example. It is coated with a certain polyacetal resin so that it can be charged by the frictional action of a scraper 21 constituting the scraping means. The scraper 21 is made of, for example, flaky polyester resin,
Its proximal end is fixed to the apparatus main body 2 side via an elastic member 22 so that its tip presses against the surface of the driven roller 17b, and the paper dust, etc. transferred and attached to the surface of the driven roller 17b is removed. At the same time as scraping off, the surface of the driven roller 17b is charged. Furthermore, in this embodiment, the photosensitive drum 7, the charging device 9, the developing device 12, and the cleaner device 14 are housed within the cover unit 23 to constitute one unit body 25, and the cover unit 23 is configured to constitute one unit body 25. 2
3, as shown in FIGS. 2 and 4, slide parts 23a, 23b are formed on the sides thereof, and a handle part 23c is attached to the front part of the slide part 23a. By grasping and pulling the portion 23c, the slide portion 23
a, 23b are fixedly installed in the device main body 2, a rail 25a;
25b, the unit body 25 can be pulled out as a whole from inside the apparatus main body 2 to the front of the apparatus main body 2, as shown in FIG.

Furthermore, as shown in FIGS. 1 and 4, a cleaning member 26 is fixed to the lower end of the cover integral 23 constituting the unit body 25, and the cleaning member 26 is made of urethane. A felt 26b or the like is pasted on a base 26a made of an elastic body such as a foam, and the felt 26b is brought into contact with the upper end of the driven roller 17b and the scraper 21 with appropriate pressure due to the elastic force of the base 26a. There is. Furthermore, a slit 23d is formed on the upper surface of the cover unit 23 facing the electrically conductive element array 11 for exposure.

Since this embodiment has the above-described configuration, when the drive roller 17a of the registration roller pair 17 is rotated to convey the transfer paper P, the driven roller 17b that is in contact with the drive roller 17a also rotates. The drive roller 17a rotates as the drive roller 17a rotates, and static electricity is generated due to friction between the surface of the driven roller 17b and the tip of the scraper 21 due to the rotation, and the surface of the driven roller 17b becomes electrically charged. Then, in order to transfer the developed toner image onto the photoreceptor drum 7, the transfer paper P is transferred from the paper feed section 5 to the registration roller pair 17.
When the transfer paper P is conveyed toward the transfer paper P and is held between the pair of registration rollers 17, the electrostatic adsorption action on the surface of the charged driven roller 17b causes the paper dust, etc. present on the transfer paper P to be removed from the transfer paper P. The transfer paper P is transferred and adhered onto the surface of the driven roller 17b, and while the transfer paper P passes through the registration rollers 17, the transfer paper P becomes in a clean state with almost no paper dust or the like present thereon. In this way, paper dust, etc. transferred from the transfer paper P to the surface of the driven roller 17b is scraped off by the tip of the scraper 21, which contacts the roller 17b over almost its entire width, based on the rotation of the driven roller 17b itself. scraper 21
After passing through the scraper 21, the surface of the driven roller 17b is in a clean and charged state.
It is returned to its original position and is brought into rotational contact with the transfer paper P that is being conveyed again to adsorb paper dust and the like. The photoreceptor on the photoreceptor drum 7 is replaced periodically or depending on the deterioration of its performance, and the toner filled in the developing device 12 is replenished periodically or when the toner runs out. However, when the unit body 25 is pulled out from the apparatus main body 2 when replacing, replenishing, or maintaining other parts, the unit body 25 is fixedly attached to the unit body 25 side and is pressed against the scraper 21 and the driven roller 17b. The cleaning member 26 that is present is also moved at the same time. Therefore, as the cleaning member 26 moves, paper powder, etc. that has accumulated on the scraper 21 provided on the device main body 2 side is brushed off from above the scraper 21 to a location below the device main body 2 where there is no problem. At the same time, the peripheral portion of the scraper 21 of the driven roller 17b is also cleaned.

Next, a partially modified embodiment will be described based on FIG. 5. - In this embodiment, a resin roller 27 is rotatably disposed on the front side of the registration roller pair 17 in the conveyance direction, and the resin roller lightly contacts the transfer paper P. In addition, the resin roller 27
A charging means such as a corotron 29 is disposed opposite to the resin roller 27, and the resin roller 27 is charged by the corotron 29. Furthermore, a scraping/cleaning member 30 having an abbreviated shape is fixed to the lower end of the cover unit 23.
0 is made up of a felt 26b pasted on a base 26a made of an elastic body, and as shown in detail in FIG. 5(b),
A cleaning member 26M is formed protruding in the circumferential direction of the roller 27 at the back end, and a scraping member 26N is formed protruding from the cleaning member 26M in the width direction of the roller 27.
is formed.

Then, the scraping member 26N contacts the roller 27 over a width wider than the maximum paper passing area passing through the -ra 27, and also contacts the cleaning member 26M and the roller 27.
That is, the cleaning member 2 is retracted in the direction of rotation of the cleaning member 2.
6M protrudes upstream in the rotational direction from the vertical plane of the rotational axis of the roller 27, whereas the scraping member 26N is retracted and disposed downstream from the vertical plane in the rotational direction.

Since this embodiment has the above-described configuration, as the transfer paper P is conveyed, the resin roller 27 is rotated in contact with the transfer paper P, and the surface of the resin roller 27, which is charged based on the corotron 29, is electrostatically attracted. Due to this action, paper dust and the like are transferred and attached to the surface of the resin roller 27. Furthermore, the adhered paper powder and the like are scraped off by the scraping member 26N by the rotation of the resin roller 27, and deposited on the resin roller 27 in front of the scraping member 26N. When the unit body 25 is pulled out from the inside of the apparatus main body 2, the cleaning member 26M moves on the roller 27 while making contact with the front, so that the paper powder etc. accumulated on the roller 27 is removed from the apparatus main body 2. It is brushed off internally downward.

In each embodiment, the unit body 25 includes the photosensitive drum 7, the charging device 9, the developing device 12, and the cleaner device 1.
4 is housed in the cover unit 23, however, it is sufficient that the unit body 25 holds at least the photosensitive tram 7 or the developing device 12.

Further, the cleaning operation of the scraper 21 is performed by the unit body 2.
Although the cleaning operation has been described as being carried out when the unit body 5 is pulled out, the cleaning operation may also be carried out when the pulled out unit body 25 is stored, or the shape of the opening 23d formed in the cover body 23 may be changed. It may be modified such that the cleaning operation of the scraper 21 is performed in one direction only when the unit body 25 is pulled out or stored.

Although the cleaning member 26 was constructed by pasting the felt 26b on a base 26a made of an elastic material such as urethane foam, it is also possible to use a base made of an elastic material such as a leaf spring, sponge, or moltoprene. Of course, the cleaning member 26 may also be constructed of a brush, raised fibers, or the like.

(g) As described in detail, according to the present invention, the rollers 17b and 27 in contact with the image transfer surface of the transfer paper P are configured to be able to be charged,
Further, a scraping member 21° 26N for scraping paper dust etc. from the transfer paper P adsorbed onto the roller is disposed in contact with the roller, and furthermore, at least the photosensitive drum 7 or the developing device 1
The scraping member 2 is configured to be able to be put in and taken out from the main body 2 of the device.
Since the cleaning means 26.26M is disposed in the unit body 25 so as to clean around 1.26N, it is extremely easy to clean the transfer paper P before it is conveyed to the transfer section during normal operation of the image forming apparatus 1. Paper dust and the like can be effectively removed with a low-cost mechanism, thereby making it possible to obtain high-quality copies and effectively delaying the deterioration of the performance of the photoreceptor on the photoreceptor drum 7. This makes it possible to prevent deterioration of the toner that is collected and reused.Furthermore, when the unit body 25 is taken in and out of the apparatus main body 2, the scraping member 21. is automatically removed by a simple and low-cost mechanism. 26
The area around N can be cleaned, thereby backing up the removal of paper dust etc. from the transfer paper P for a long period of time without requiring any manual labor. The cleaning member 26.26M can be replaced by replacing the entire unit body 25 according to the lifespan etc.
Furthermore, the scraping member 2 disposed on the unit body 25
6N can also be replaced with a new one, so cleaning member 26
．． It is possible to prevent the cleaning effect from decreasing when 26M is repeatedly used.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged front view showing the main structure of a cleaning mechanism according to the present invention, and FIG. 2 is a front view schematically showing the internal structure of a copying machine to which the cleaning mechanism of the present invention can be applied.
Fig. 3 is a perspective view of the copying machine showing the unit body pulled out from the main body of the machine, and Fig. 4 is a diagram showing the structure of the unit body, where (a) is a perspective view and (b) is an arrow shown in (a). (0) is a bottom view seen from below of (b), FIG. 5 is a diagram showing another embodiment of the present invention, (a) is a front view, (
b) is a plan view.

Claims (1)

[Claims] (1) It has a unit body 25 which is configured to be freely put in and taken out from a predetermined position in the apparatus main body 2 and includes at least the photoreceptor drum 7 or the developing device 12, and which develops the electrostatic latent image formed on the photoreceptor drum 7. In the image forming apparatus 1 configured to develop the toner image by the device 12 and transfer the developed toner image to the transfer paper P conveyed from the paper feed section 5 via the rollers 17b and 27, image transfer of the transfer paper P is performed. The rollers 17b, 27 in contact with the surface are configured to be electrically charged, and the rollers are arranged in the main body 2 of the apparatus, and a roller for scraping off paper dust etc. from the transfer paper P adsorbed onto the rollers 17b, 27 is provided. The scraping members 21 and 26N are disposed in contact with the rollers, and the unit body 25 is further cleaned to remove paper dust and the like accumulated near the scraping members 21 and 26N as the unit body 25 is taken in and out. A cleaning mechanism for an image forming apparatus, characterized in that means 26 and 26M are provided.