JP2008107661A - Lubricant applying device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricant applying device which uniformly applies a solid lubricant to the entire area in the longitudinal direction of an applying brush roller or an applying means, and to provide an image forming apparatus provided with the lubricant applying device. <P>SOLUTION: In the lubricant applying device 20 of the image forming apparatus, having the solid lubricant 22 and a pressure means 23 for pressurizing the solid lubricant 22 against the applying means 21, the applied amount of the solid lubricant 22 can be controlled by a longitudinal application area adjusting means for the solid lubricant 22 and a lubricant surface heating means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lubricant application device used in an electrophotographic apparatus such as a copying machine and a printer, and an image forming apparatus having the lubricant application device.

Conventionally, several techniques have been proposed for a lubricant application device that applies a lubricant to a photoreceptor used in an electrophotographic apparatus (see, for example, Patent Documents 1 to 6).
Patent Document 1 discloses a guide means for the pressurizing direction of the lubricant, but there is no application amount control means for the longitudinal direction of the lubricant. Patent Document 2 discloses a technique for changing the installation angle with respect to the pressurizing direction of the lubricant, but there is no means for controlling the application amount in the longitudinal direction of the lubricant.
Further, Patent Document 3 discloses a technique for changing the hardness distribution in the thickness direction of the lubricant, but the lubricant is complicated and difficult to generate. Patent Document 4 discloses a technique for pressurizing and applying a solid lubricant to a photoreceptor, and the area of the lubricant application surface varies in the longitudinal direction.

Patent Document 5 discloses a lubricant application device that heats the surface of a lubricant via an application roller incorporating a heater. In this case, a heater is provided at a position closest to the lubricant to directly heat the lubricant surface. Patent Document 6 discloses that the area of the contact portion between the lubricant and the application roller is different in the longitudinal direction.
In an image forming apparatus, a lubricant application device is used to prevent adhesion of fused toner, filming, and the like on a photosensitive member by applying a lubricant to the photosensitive member. Further, prevention of transfer omission and cleaning can be facilitated, and wear of the photoconductor and the cleaning blade can be reduced, which is useful for improving the service life thereof.
JP 2006-003537 A JP 2005-010554 A JP 2004-177811 A JP 2000-242135 A JP-A-2005-275166 JP 2002-365993 A

However, there is an appropriate amount of the solid lubricant to be applied, and if the amount is small, the above effect cannot be obtained. If the amount is too large, charging abnormalities (abnormal images) due to contamination of the charging roller with the lubricant, or the lubricant is mixed into the developer, causing toner scattering due to abnormal charging of the developer. In addition, when the coefficient of friction of the photosensitive member is low, a predetermined amount of toner cannot be adhered.
There is also a problem that when the solid lubricant is applied to the application brush roller, it cannot be applied uniformly in the longitudinal direction of the application brush roller. As a result, the lubricant cannot be evenly adhered to the photosensitive member, and the charging roller is contaminated by the lubricant slipped from the cleaning blade, thereby causing an image abnormality.
Accordingly, an object of the present invention is to provide a lubricant application device that uniformly applies a solid lubricant to the entire area in the longitudinal direction of an application brush roller or application means, and an image forming apparatus having the same in consideration of the above-described situation. There is to do.

In order to solve the above-mentioned problem, the invention described in claim 1 includes a rectangular solid lubricant, an application unit that adheres the solid lubricant and applies the solid lubricant to an application target, and the solid A pressurizing unit for pressing and adhering the lubricant to the coating unit, and a heating unit for heating the solid lubricant when the solid lubricant is pressed against the coating unit. The lubricant is characterized by a lubricant application device in which a pressing surface to the application means has a curved surface from both longitudinal ends of the solid lubricant to the longitudinal center.
The invention according to claim 2 is a rectangular solid lubricant, an application means for applying the solid lubricant to an application target, and the solid lubricant applied to the application means. A pressurizing unit for pressing and adhering the solid lubricant, and a heating unit that heats the solid lubricant when the solid lubricant is pressed against the coating unit. It is characterized by a lubricant application device provided with a plurality of holes in the pressing surface against the means.

The invention according to claim 3 is characterized in that the hole is provided more on both sides in the longitudinal direction than in the longitudinal center of the pressing surface. To do.
According to a fourth aspect of the present invention, there is provided a solid lubricant, an application means for applying the solid lubricant to an application target, and the solid lubricant being pressed against the application means. And a pressurizing means for heating the solid lubricant when pressed against the applying means, the solid lubricant comprising a plurality of solid lubricant pieces superimposed on each other. It features a configured lubricant application device.
Further, the invention according to claim 5 is configured such that the solid lubricant has an area in the center portion in the longitudinal direction of the pressing surface to the coating means larger than areas in both sides in the longitudinal direction. Features the described lubricant applicator.

The invention according to claim 6 is characterized in that the lubricant application device according to any one of claims 1 to 5 is provided with a temperature control means for controlling a heating temperature of the heating means. To do.
A seventh aspect of the present invention is characterized in that the heating means is a heater.
The invention according to claim 8 is characterized in that the temperature control means controls the temperature according to the unit temperature, and the lubricant application device according to claim 6 or 7.
According to a ninth aspect of the present invention, there is provided an image forming apparatus provided with the lubricant application device according to any one of the first to eighth aspects.

  According to the present invention, by changing the area ratio of both sides and near the center of the shape of the solid lubricant with respect to the longitudinal direction, the area pressed against the coating brush roller can be changed, so the solid lubricant is uniform in the longitudinal direction of the coating brush roller. The solid lubricant can be heated in the longitudinal direction by the longitudinal heating mechanism and temperature control mechanism of the solid lubricant, and the amount of application to the application brush roller can be controlled to uniformly adhere to the photoreceptor. Is possible.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view of the main part of an image forming apparatus according to the present invention. Referring to FIG. 1, image formation in image forming apparatus 10 is performed with the following configuration and operation. First, the photoreceptor 11 rotates clockwise with respect to the paper surface. After the photoreceptor 11 is uniformly charged by the charging device 12, the exposure device 13 exposes the image portion to form a latent image.
Thereafter, the latent image is developed with toner by the developing device 14 to be visualized, and the reference pattern is transferred by the transfer roller 15 to the transfer paper P fed through a registration roller 16 from a paper feeding device (not shown) and fixed. It is conveyed to the nip portion between the fixing roller 17 and the pressure roller 18 of the apparatus 1 and fixed.
Although not shown, the developing roller 19 of the developing device 14 includes a magnet roller having a plurality of fixed magnetic poles, a nonmagnetic developing sleeve that is rotatably provided on the outer periphery of the magnet roller, and a fixed and centered one side of the developing sleeve. The magnet roller has a flange on which the magnet roller is pivotally supported, and the toner is held on the developing sleeve and conveyed to the photoreceptor 11.

FIG. 2 is a schematic front view showing the structure of a general lubricant application device used in the image forming apparatus. FIG. 3 is a schematic side view of the lubricant application device of FIG. In the lubricant application device 20 shown in FIGS. 2 and 3, the application brush roller 21 is rotatable with respect to the photoreceptor 11 and is installed with a predetermined amount of biting.
A solid lubricant 22 is brought into contact with the application brush roller 21 by the elasticity of the pressure spring 23. The solid lubricant 22 may be zinc stearate. Further, as a process configuration, the application brush roller 21 is brought into contact with the photosensitive member 11, and then the cleaning blade 24 and the charging roller 12 are arranged.
Here, when the solid lubricant 22 is excessively adhered to the photoconductor 11 and when there is uneven coating in the longitudinal direction of the photoconductor 11, the solid lubricant 22 slips from the cleaning blade 24 and charges the charging roller 12. When the electric potential is applied, the charging roller 12 is contaminated.

FIG. 2 shows a state in which the charging roller dirt is generated in the longitudinal direction of the charging roller 12. In this example, the charging roller 12 has a large amount of dirt on both sides in the longitudinal direction. This results in image smearing.
2 and 3, the application brush roller 21 is supported at both ends in FIG. 2 and FIG. 3, and the solid lubricant 22 is strongly pressed at both ends, and the portion adheres to the photoconductor 11 a lot. The reason is that the cleaning blade 24 slips through.

FIG. 4 is a schematic perspective view showing a first form of the solid lubricant shape of the lubricant application device of the present invention. A first embodiment of the present invention will be described with reference to FIG.
The shape of the solid lubricant 25 in FIG. 4 is thickened with a curved surface from both longitudinal ends 25A to the central portion 25B to form a so-called drum-shaped body. This shape is useful as a means for adjusting the application area of the solid lubricant 22 in the longitudinal direction.
Both ends 25A are narrowed, and the application distance is changed by changing the contact distance in the width direction of the solid lubricant 25 with respect to the circumferential direction of the application brush roller 21 (FIG. 3). The shape may be changed step by step.
Thus, since the area pressed against the application brush roller 21 can be changed by changing the ratio of the area of the solid lubricant 25 on both sides and near the center with respect to the longitudinal direction, the longitudinal direction of the application brush roller 21 can be changed. Can be applied uniformly.

FIG. 5 is a schematic perspective view showing a second form of the solid lubricant shape of the lubricant application device of the present invention. FIG. 6 is a schematic view showing a modification of the second form of the solid lubricant shape.
In the second embodiment of FIG. 5, the entire solid lubricant 26 is formed into a square body, and punched holes (holes) 26 </ b> A and 26 </ b> B are provided. This shape is useful as a means for adjusting the application area of the solid lubricant 22 in the longitudinal direction.
The holes 26A and 26B increase the number of holes on both sides with respect to the longitudinal direction of the solid lubricant 26, and decrease the number of holes toward the center. That is, the hole 26A is a hole on both sides, and the hole 26B is a hole in the center.

Thus, the contact distance is changed in the width direction of the solid lubricant 26 with respect to the circumferential direction of the application brush roller 21 (FIG. 3) to control the application amount. The hole shape may be a round hole 26C or another different shape as shown in FIG.
Thus, since the area pressed against the application brush roller 21 can be changed by changing the area ratio of the solid lubricant 26 on both sides and near the center with respect to the longitudinal direction, the longitudinal direction of the application brush roller 21 can be changed. Can be applied uniformly.

FIG. 7 is a schematic perspective view showing a third form of the solid lubricant shape of the lubricant application device of the present invention. In the third form of the solid lubricant shape in FIG. 7, the solid lubricant 27 shows a palm structure that is a building block shape in which a plurality of solid lubricant pieces are combined. This shape is useful as a means for adjusting the application area of the solid lubricant 22 in the longitudinal direction.
There are few combinations of this palm structure at both ends 27A, and the width is widened by the overlapping structure near the central portion 27B. Arbitrary combinations are possible, and the coating area can be changed with respect to the longitudinal direction.
Thus, since the area pressed against the application brush roller 21 can be changed by changing the area ratio of the solid lubricant 27 in the longitudinal direction on both sides and in the vicinity of the central portion, the longitudinal direction of the application brush roller 21 can be changed. Can be applied uniformly.

FIG. 8 is a schematic side view showing an embodiment of the coating material heating control device for the longitudinal direction of the solid lubricant. FIG. 9 is a surface view showing details of the coating material heating control apparatus of FIG. With reference to FIGS. 8 and 9, a plurality of heaters 29 are arranged as heating bodies (heating means) in the longitudinal direction of the solid lubricant 28.
In this embodiment, a temperature sensor 30 is arranged in each heater 29, and the temperature can also be detected. Note that the heating temperature can be controlled within a predetermined range via a temperature control device (temperature control means) 31 on both sides in the longitudinal direction of the solid lubricant 28 and near the center. According to this configuration, stepwise and arbitrary temperature settings are possible.
With this configuration operation, the solid lubricant 28 can be applied while controlling the temperature in the longitudinal direction of the application brush roller (not shown), uniformly heating, and rotating. Thus, the longitudinal heating control mechanism and the temperature control mechanism 31 of the solid lubricant 28 can control the heating of the solid lubricant 28 in the longitudinal direction, and the photosensitive member (not shown) can be controlled by controlling the amount of application to the application brush roller. ) Can be evenly attached.

FIG. 10 is a graph showing a temperature change of the in-machine unit including the lubricant applying device in the image forming apparatus. FIG. 10 shows the temperature change of the in-machine unit including the lubricant application device in the image forming apparatus, and has a unit temperature unstable time region until the unit becomes stable after startup.
In the present invention, the solid lubricant is heated up to the stable region of the in-flight unit after the power is turned on, and the state is made in the stable region in the initial early state. Regarding the control temperature, a temperature sensor 30 (FIG. 9) is disposed around the solid lubricant, and the temperature can be controlled while monitoring the state.
As a result, it is possible to avoid the influence at the time of starting up the machine, and to control seasonal fluctuations and local temperature differences. The temperature control device 31 (FIG. 9) can control the temperature of the solid lubricant in the initial unstable temperature region with respect to the temperature rise characteristics of the in-machine unit, and can be stabilized in the image forming apparatus.

  By mounting the lubricant coating apparatus having the above-described configuration, an image forming apparatus with stabilized images can be provided. In addition, it is possible to avoid the influence at the time of starting up the machine and to control seasonal fluctuations and local temperature differences.

1 is a schematic diagram showing a main part of an image forming apparatus according to the present invention. 1 is a schematic front view showing a structure of a general lubricant application device used in an image forming apparatus. FIG. 3 is a schematic side view of the lubricant application device of FIG. 2. The schematic perspective view which shows 1st Embodiment of the solid lubricant shape of the lubricant coating device of this invention. The schematic perspective view which shows 2nd Embodiment of the solid lubricant shape of the lubricant coating device of this invention. Schematic which shows the modification in 2nd Embodiment of solid lubricant shape. The schematic perspective view which shows 3rd Embodiment of the solid lubricant shape of the lubricant coating device of this invention. The schematic side view which shows embodiment of the coating material heating control apparatus with respect to the longitudinal direction of a solid lubricant. The surface view which shows the detail of the coating material heating control apparatus of FIG. The figure which shows the temperature change of the in-machine unit containing the lubricant coating device in an image forming apparatus with a graph.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Image forming apparatus, 11 Photoconductor, 12 Charging apparatus (charging roller), 20 Lubricant application apparatus, 21 Application brush roller (application means), 22 Solid lubricant, 23 Pressurization means (pressure spring), 25 Solid lubrication Agent (Drum-shaped body), 25A Narrow ends (longitudinal direction application area adjustment means), 25B Thick central part (longitudinal direction application area adjustment means), 26 Solid lubricant (square shape body), 26A Holes (both ends) , Longitudinal application area adjusting means), 26B punch hole (center, longitudinal application area adjusting means), 26C punch hole (round hole), 27 solid lubricant (block-shaped body), 27A both ends without overlapping (longitudinal) Direction application area adjustment means), 27B superposition near the center (longitudinal direction application area adjustment means), 28 solid lubricant, 29 heater, 30 temperature sensor, 31 temperature control device

Claims (9)

A rectangular solid lubricant; an application means for applying the solid lubricant to the application target; and a pressurizing means for applying the solid lubricant by pressing the solid lubricant against the application means. In the lubricant application device
A heating means for heating the solid lubricant at the time of pressing the solid lubricant to the application means;
The lubricant application device according to claim 1, wherein the pressing surface of the solid lubricant has a curved surface from both ends in the longitudinal direction to the center in the longitudinal direction of the solid lubricant. A rectangular solid lubricant; an application means for applying the solid lubricant to the application target; and a pressurizing means for applying the solid lubricant by pressing the solid lubricant against the application means. In the lubricant application device
A heating unit that heats the solid lubricant when the solid lubricant is pressed against the application unit;
The solid lubricant is provided with a plurality of holes in a pressing surface against the coating means.   The lubricant application device according to claim 2, wherein a larger number of the hole portions are provided on both sides in the longitudinal direction than the central portion in the longitudinal direction of the pressing surface. Lubricant comprising: a solid lubricant; an application means for applying the solid lubricant to an application target; and a pressurizing means for pressing the solid lubricant against the application means to attach the solid lubricant. In the coating device,
A heating means for heating the solid lubricant when pressed against the application means;
The solid lubricant is a lubricant application device configured by superposing a plurality of solid lubricant pieces.   5. The lubricant application device according to claim 4, wherein the solid lubricant is configured such that an area in a longitudinal center portion of a pressing surface to the application means is larger than areas on both sides in the longitudinal direction.   6. The lubricant application device according to claim 1, further comprising a temperature control unit that controls a heating temperature of the heating unit.   The lubricant application apparatus according to claim 6, wherein the heating unit is a heater.   The lubricant application device according to claim 6 or 7, wherein the temperature control means controls the temperature according to a unit temperature.   An image forming apparatus comprising the lubricant application device according to claim 1.

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