JP2001051466A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent failure from occurring caused by the excessive supply of lubricant by more increasing the quantity of the lubricant supplied to an electrostatic latent image carrier of one image forming part from a lubricant supply means than that of the lubricant supplied to the electrostatic latent image carriers of the respective image forming parts other than one image forming part out of the plural image forming parts. SOLUTION: This device is provided with the lubricant supply means 30B, 30C, 30M and 30Y. Then, the quantity of the lubricant supplied to the electrostatic latent image carrier 10B of one prescribed image forming part 1B out of the plural image forming parts 1B, 1C, 1M and 1Y from the supply means 30B is more increased than that of the lubricant supplied to the respective electrostatic latent image carriers 10C, 10M and 10Y of the image forming part 1C, 1M and 1Y other than one image forming part 1B. Thus, an effect for prolonging the service life of the carrier 10B is not lowered and the failure is prevented from occurring caused by the excessive supply of the lubricant even when the quantity of the lubricant eliminated from one image forming part is large in comparison with that from the other image forming parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a plurality of image forming units, such as a copying machine, a facsimile, and a laser printer.

[0002]

2. Description of the Related Art First, an electrophotographic image forming unit as shown in FIG. 4 in a color image forming apparatus will be described. The image forming unit 1B includes a drum-shaped photoconductor 10 as an electrostatic latent image carrier.
B is an image forming part for forming a black image on
OB is rotationally driven by a drive mechanism (not shown). The surface of the photoreceptor 10B is uniformly charged by a charging roller 11B as a charging unit, and then is exposed to exposure light 12B from an exposure unit (including an optical writing device) (not shown) to form an electrostatic latent image. Then, the image is visualized with a black developer (a one-component developer composed of only a black toner or a two-component developer composed of a black toner and a carrier) by a developing device 13B as a developing unit to form a black toner image.

The black toner image on the photoreceptor 10B is transferred to a transfer paper as a transfer body by a transfer belt 14 in a transfer step as will be described later.
5B, and the transfer sheet is discharged after a black toner image is fixed by a fixing device (not shown). A cleaning blade 17B as a cleaning member in the cleaning device 16B cleans the photoconductor 10B after transfer to remove toner remaining on the surface of the photoconductor 10B from the photoconductor 10B, and is removed from the photoconductor 10B by the cleaning blade 17B. The toner is transported to a waste toner storage unit (not shown) by a waste toner transport screw 19B. Further, the cleaning device 16B is provided with a cleaning brush 18B as a cleaning auxiliary member that disturbs and removes toner on the surface of the photoconductor 10B on the upstream side of the cleaning blade 17B in the moving direction of the photoconductor 10B.

FIG. 3 shows an example of a color image forming apparatus.
This color image forming apparatus includes four image forming units 1B, 1C,
1M and 1Y are arranged in parallel, and a transfer belt 14 for transporting transfer paper is provided. The image forming unit 1B for forming a black toner image is the same as the image forming unit 1B shown in FIG. 4, and the other image forming units 1C, 1M, and 1Y are almost the same as the image forming unit 1B.

That is, the image forming units 1C, 1M, and 1Y are respectively provided with drum-shaped photosensitive members 10C, 1C, which are electrostatic latent image carriers.
0M, 10Y, a cyan toner image, a magenta toner image,
This is an image forming unit that forms a yellow toner image, and the photoconductors 10C, 10M, and 10Y are rotationally driven by a driving mechanism (not shown). These photoconductors 10C, 10M, 10Y
Are charging rollers 11C and 11C as charging means, respectively.
After the surface is uniformly charged by M and 11Y, exposure light 1 from an exposure means (including an optical writing device) not shown
Exposure is performed by 2C, 12M and 12Y to form an electrostatic latent image, and developing devices 13C, 13M and 13Y as developing means
From a cyan developer (a one-component developer consisting of only a cyan toner or a two-component developer consisting of a cyan toner and a carrier), a magenta developer (a one-component developer consisting of only a magenta toner, or a magenta toner and a carrier). Two-component developer) and a yellow developer (a one-component developer consisting only of a yellow toner or a two-component developer consisting of a yellow toner and a carrier) to form a cyan toner image, a magenta toner image, and a yellow toner, respectively. It becomes a toner image.

The transfer paper is fed from a paper feeding device (not shown), is conveyed by a transfer belt 14, and after the black toner image on the photoreceptor 10B is transferred by the transfer brush 15B as described above, the photoreceptor 10C, Transfer brushes 15C, 15M, and 15Y as transfer means are provided for cyan, magenta, and yellow toner images on 10M and 10Y.
, A full-color image is formed. The transfer paper on which the full-color image is formed is fixed with a full-color toner image by a fixing device (not shown) and is discharged.

[0007] Cleaning devices 16C, 16M, 16Y
Cleaning blade 1 as a cleaning member inside
7C, 17M, and 17Y are the photoconductors 10 after the transfer, respectively.
C, 10M, and 10Y are cleaned and the photoconductor 10C is cleaned.
10M, the toner remaining on the 10Y surface is
10M and 10Y, and the photoconductors 10C, 10M and 10Y are removed by the cleaning blades 17C, 17M and 17Y.
The toner removed from 10Y is transported to a waste toner storage unit (not shown) by waste toner transport screws 19C, 19M, and 19Y.

Further, the creasing devices 16C and 16
M and 16Y are cleaning blades 17C and 17M,
Cleaning brushes 18C, 18M, and 18Y as cleaning auxiliary members for disturbing and removing toner on the surfaces of the photoconductors 10C, 10M, and 10Y are provided on the upstream side of the 17Y photoconductors 10C, 10M, and 10Y in the moving direction.
A color image forming apparatus that obtains a desired full-color image using a black toner, a cyan toner, a magenta toner, and a yellow toner (a so-called tandem method) is known.

In addition, in an electrophotographic image forming apparatus, a technique is known in which a lubricant is supplied to a photoreceptor to prevent abrasion of the surface of the photoreceptor by a cleaning belt or the like, and to prevent shortening of a life due to abrasion of the photoreceptor. There are various proposals for the lubricant supply system. As a lubricant supply system, a system in which a lubricant is directly pressed and supplied to the surface of a photoreceptor is described in, for example, Japanese Patent Application Laid-Open No. 9-62163, in which a rotating brush roller is brought into contact with the photoreceptor and Japanese Patent Laid-Open No. 6-324 discloses a system in which a lubricant is brought into contact with a photosensitive member via a brush roller.
No. 603. As the latter method, since there are many image forming apparatuses in which a brush roller is provided in a cleaning unit that collects residual toner on a photoconductor, a method in which the brush roller is used is proposed.

[0010]

In the above-described image forming apparatus, when the supply of the lubricant to the photoconductor is considered, the amount of the supplied lubricant is inconvenient because the lubricant accumulates on the surface of the photoconductor and foreign matters are mixed therein. It is necessary that the lubricant be removed from the surface of the photoreceptor before supplying the lubricant and before the re-supply, so that a fresh lubricant is always formed on the surface of the photoreceptor. Is preferred.

Here, an appropriate amount of the lubricant to be supplied to the surface of the photoreceptor is determined by a balance between the amount of the supplied lubricant and the amount of the lubricant removed in the electrophotographic process. Factors for removing the lubricant from the photoreceptor surface include sliding contact between the developer and the lubricant in the developing unit, and scraping of the lubricant by a cleaning blade, and the like, which differs depending on the configuration of the image forming unit. For this reason, the removal amount of the lubricant differs depending on the configuration of the image forming unit, and it is necessary to set the lubricant supply amount according to the removal amount.

In the tandem type image forming apparatus, it is desirable that the mechanical construction of each image forming unit is the same in consideration of the apparatus cost. For this reason, considering only the mechanical configuration, the above-described lubricant removal amount can be set equal in each image forming unit, and the lubricant supply amount can be set equal in each image forming unit. However, in a tandem image forming apparatus that mainly forms a color image, as described above, a black toner, a cyan toner, a magenta toner, and a yellow toner are used, and the contribution of these toners to a lubricant is not exactly the same.

More specifically, the cyan toner, the magenta toner and the yellow toner have pigments corresponding to respective colors added to the base resin, whereas the black toner has carbon added to the base resin. . Therefore, when the toner slides on the photoreceptor surface, the black toner to which hard carbon is added has a higher sliding contact ability than other toners, and a large amount of the lubricant on the photoreceptor surface is scraped off to remove the photoreceptor surface. The effect of extending the service life by supplying the lubricant is diminished.

According to the first aspect of the present invention, when the life of the electrostatic latent image carrier is extended by supplying a lubricant to the electrostatic latent image carrier, one image forming unit can use another image forming unit. An image forming apparatus that does not reduce the effect of prolonging the life of the electrostatic latent image carrier even if the amount of lubricant removed is large, and can prevent the occurrence of problems due to excessive supply of lubricant. The purpose is to provide.

According to a second aspect of the present invention, the long life of the electrostatic latent image carrier of the image forming unit is increased even if the amount of lubricant removed from the image forming unit is increased due to the carbon contained in the black toner. It is an object of the present invention to provide an image forming apparatus which does not reduce the effect of image formation and can prevent the occurrence of problems due to excessive supply of lubricant.

[0016]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 provides an electrostatic latent image carrier having a surface on which an electrostatic latent image is formed, and an electrostatic latent image carrier on the electrostatic latent image carrier. A plurality of image forming units each having a developing device that visualizes the electrostatic latent image to form a toner image, and a cleaning device that cleans the electrostatic latent image carrier. Each of the plurality of image forming units An image forming apparatus that transfers a toner image on an electrostatic latent image carrier to a transfer body, comprising: a lubricant supply unit that supplies a lubricant to each electrostatic latent image carrier of the plurality of image forming units. The amount of lubricant supplied from the lubricant supply unit to the electrostatic latent image carrier of a predetermined one of the plurality of image forming units is changed from the lubricant supply unit to the plurality of image forming units. The amount of lubricant supplied to each electrostatic latent image carrier of the image forming unit other than the one image forming unit Those were.

According to a second aspect of the present invention, in the image forming apparatus of the first aspect, the plurality of image forming units use a black developer, a cyan developer, a magenta developer, and a yellow developer, respectively. And the one image forming unit is an image forming unit using a black developer.

[0018]

FIG. 1 shows an embodiment of the present invention.
FIG. 2 shows one image forming section of this embodiment. This embodiment is an embodiment of the first and second aspects of the present invention. In this embodiment, in the tandem-type image forming apparatus shown in FIG. 3, each of the image forming units 1B, 1C, 1M, and 1Y has a lubricant application unit 30B, 30C, 30 serving as a lubricant supply unit.
M and 30Y are added. This lubricant application section 30
B, 30C, 30M, and 30Y are the cleaning devices 16
The cleaning brushes 18B, 18C, 18M, and 18Y include the lubricants 31B, 31C, 31M, and 31Y supported in B, 16C, 16M, and 16Y. The lubricants 31B, 31C, 31M, and 31Y are provided so as to contact the cleaning brushes 18B, 18C, 18M, and 18Y.

Cleaning brushes 18B, 18C, 18
M and 18Y are rotationally driven by a drive mechanism (not shown). The lubricants 31B, 31C, 31M, and 31Y are scraped off by the cleaning brushes 18B, 18C, 18M, and 18Y, and the cleaning brushes 18B, 18C, and 18Y are removed.
After attaching to the surface of M, 18Y, cleaning brush 1
8B, 18C, 18M, and 18Y are the photoconductors 10B and 10B.
C, 10M and 10Y, the cleaning brushes 18B, 18C, 18M and 18Y
0C, 10M, and 10Y, and the photoconductors 10B, 10
A layer of a lubricant is formed on the surfaces of C, 10M, and 10Y.

In the image forming units 1C, 1M, and 1Y for forming a cyan toner image, a magenta toner image, and a yellow toner image on the surfaces of the photoconductors 10C, 10M, and 10Y, brush rollers (cleaning brushes) 18C, 18M, and 18Y The photoreceptors 10C, 10M, and 10Y are rotationally driven by a driving mechanism at a rotational speed appropriate for supplying an appropriate amount of lubricant to the photoreceptors.

In the image forming section 1B for forming a black toner image on the surface of the photoreceptor 10B, the brush roller (cleaning brush) 18B is driven to rotate by a driving mechanism. , 1M, 1Y
The contribution of the toner to the lubricant (the contribution of removing the lubricant from the photoreceptor) is greater than that of the other image forming units 1C and 1C.
The rotation speed of the brush roller 18B is higher than the rotation speeds of the M, 1Y brush rollers 18C, 18M, 18Y. For this reason, the supply amount of the lubricant to the photoconductor 10B increases, and the effect of extending the life by supplying the lubricant to the photoconductor 10B is not diminished. However, as described above, the rotation speed of the brush roller 18B is set to a predetermined rotation speed so as to avoid a problem due to the excessive supply of the lubricant, and the lubricant supply amount to the photoconductor 10B is regulated to an appropriate amount.

As described above, according to this embodiment, the photosensitive member 1 as an electrostatic latent image carrier having an electrostatic latent image formed on the surface thereof
0B, 10C, 10M, and 10Y, and developing devices 13B, 1B as developing devices that visualize the electrostatic latent images on the electrostatic latent image carriers 10B, 10C, 10M, and 10Y to form toner images.
3C, 13M, and 13Y, and the electrostatic latent image carrier 10B,
A plurality of image forming units 1B, 1C, 1M, and 1Y having cleaning devices 16B, 16C, 16M, and 16Y for cleaning 10C, 10M, and 10Y are provided. Each electrostatic latent image carrier 10
In an image forming apparatus for transferring the toner images on B, 10C, 10M, and 10Y onto transfer paper as a transfer body, each of the plurality of image forming units 1B, 1C, 1M, and 1Y has an electrostatic latent image carrier 10B, Lubricant application sections 30B, 30C, 3 as lubricant supply means for supplying a lubricant to 10C, 10M, and 10Y
0M, 30Y, and lubricating from the lubricant supply means 30B to the electrostatic latent image carrier 10B of a predetermined one of the plurality of image forming units 1B, 1C, 1M, 1Y. The amount of the supplied lubricant is 30C, 30M, 30Y
From the plurality of image forming units 1B, 1C, 1M, and 1Y other than the one image forming unit 1B.
The amount of lubricant supplied to each of the electrostatic latent image carriers 10C, 10M, and 10Y is increased so that the lubricant is supplied to the electrostatic latent image carrier to provide a long service life of the electrostatic latent image carrier. Even if the amount of lubricant removed in one image forming unit is larger than that in other image forming units, the effect of extending the life of the electrostatic latent image carrier is not reduced, and Problems can be prevented from occurring due to excessive supply of the agent.

According to this embodiment, the plurality of image forming units 1B, 1C, 1M, and 1Y are image forming units using a black developer, a cyan developer, a magenta developer, and a yellow developer, respectively. In addition, since the one image forming unit 1B is an image forming unit using a black developer, even if the amount of lubricant removed in the image forming unit for forming a black image increases due to carbon contained in the black toner, the image forming unit 1B may perform the image forming. It is possible to prevent the effect of prolonging the service life of the electrostatic latent image carrier of the portion from being reduced, and to prevent the occurrence of trouble due to excessive supply of the lubricant.

The present invention is not limited to the above embodiment. For example, a toner image on an electrostatic latent image carrier of each image forming section is transferred by being superimposed on an intermediate transfer member as a transfer member. The present invention can also be applied to an image forming apparatus that transfers the image to a transfer sheet later. In the above embodiment, the drum-shaped photoconductor is used. However, the present invention can be applied to an image forming apparatus using a belt-shaped photoconductor, a sheet-shaped photoconductor, or the like.

[0025]

As described above, according to the first aspect of the invention, when the life of the electrostatic latent image carrier is extended by supplying the lubricant to the electrostatic latent image carrier, one operation is performed. Even if the amount of lubricant removed in the image area is larger than that in the other image forming areas, the effect of extending the life of the electrostatic latent image carrier is not diminished. Can be prevented.

According to the second aspect of the present invention, the carbon contained in the black toner increases the amount of the lubricant removed from the image forming portion for forming the black image even if the electrostatic latent image carrier of the image forming portion is removed. It is possible to prevent the effect of extending the service life from being weakened and to prevent the occurrence of problems due to excessive supply of the lubricant.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing one image forming unit of the embodiment.

FIG. 3 is a cross-sectional view illustrating an example of a color image forming apparatus.

FIG. 4 is a cross-sectional view illustrating one image forming unit in the color image forming apparatus.

[Explanation of symbols]

1B, 1C, 1M, 1Y Image forming unit 10B, 10C, 10M, 10Y Photoconductor 13B, 13C, 13M, 13Y Developing unit 16B, 16C, 16M, 16Y Cleaning device 30B, 30C, 30M, 30Y Lubricant applying unit

Claims (2)

[Claims] An electrostatic latent image carrier having an electrostatic latent image formed on a surface thereof; a developing device for visualizing the electrostatic latent image on the electrostatic latent image carrier to form a toner image; An image forming apparatus including a plurality of image forming units having a cleaning device for cleaning an electrostatic latent image carrier, and transferring toner images on the respective electrostatic latent image carriers of the plurality of image forming units to a transfer body , A lubricant supply means for supplying a lubricant to each of the electrostatic latent image carriers of the plurality of image forming sections, and a predetermined one of the plurality of image forming sections from the lubricant supply means. The amount of lubricant supplied to the electrostatic latent image carrier of one image forming unit is changed from the lubricant supply unit to the electrostatic latent image carrier of each of the plurality of image forming units other than the one image forming unit. An image forming apparatus, wherein the amount of lubricant supplied to an image carrier is configured to be larger than the amount of lubricant supplied. 2. The image forming apparatus according to claim 1, wherein said plurality of image forming units are image forming units using a black developer, a cyan developer, a magenta developer, and a yellow developer, respectively. An image forming apparatus, wherein one image forming unit is an image forming unit using a black developer.