JP2013033090A - Lubricant application device, process cartridge, and image forming apparatus - Google Patents

Abstract

[PROBLEMS] To prevent uneven wear (bias consumption) in the longitudinal direction of a solid lubricant with a simple and inexpensive component structure, to prevent uneven application of the lubricant, excessive application, and insufficient application of the lubricant. It prevents charging unevenness due to dirt on the charging member caused by powder, and abnormal images caused by photoconductor filming when coating is insufficient.
A lubricant application device 20 lubricates a solid lubricant 21, a lubricant application member 22 for applying a lubricant component scraped off from the solid lubricant by rotation to an image carrier, and a solid lubricant. A pressurizing unit P1 that pressurizes the agent applying member side, and the pressurizing unit includes a main pressurizing unit P1 that pressurizes the solid lubricant and the lubricant applying unit uniformly over the entire contact surface thereof. And an auxiliary pressurizing unit P2 that pressurizes the solid lubricant in order to correct the deviation when the pressure applied by the main pressurizing unit has a deviation along the longitudinal direction of the contact surface.
[Selection] Figure 6

Description

  The present invention relates to a lubricant supply device for supplying a lubricant component scraped from a solid lubricant to an image carrier as a lubricant supply target, a process cartridge having the lubricant supply device, and a lubricant supply device or a process cartridge. The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile.

An image forming apparatus using an electrophotographic process includes a photoconductor as an image carrier, discharges the surface of the photoconductor to charge it, and exposes the charged photoconductor surface to form an electrostatic latent image. Then, toner is supplied to the electrostatic latent image to make it visible, and the visible image formed on the surface of the photoreceptor is transferred to the surface of the transfer paper, and then fixed and discharged.
Since untransferred toner or the like remains on the surface of the photoconductor after the toner image is transferred to the transfer paper, the surface of the photoconductor is cleaned by a cleaning device so that these residues do not adversely affect the next image forming process. To be cleaned. As a cleaning device, a device that removes deposits such as untransferred toner by bringing a cleaning blade made of an elastic material such as rubber into contact with the surface of the photosensitive member is generally known. In the following, in this specification, “contact in a contact state” is expressed as “contact”.

By the way, in recent years, a demand for higher image quality has been increasing, and in order to realize particularly high-definition color image formation, toner particle diameters and spheroidization have been promoted. The reproducibility of dots is improved by reducing the particle size, and the developability and transferability can be improved by making the particles spherical. In producing a toner having a reduced particle size and a spherical shape, a polymerization method such as a suspension polymerization method, an emulsion polymerization method, or a dispersion polymerization method is being adopted instead of the conventional kneading and pulverization method.
However, when a toner having a spherical shape and a reduced particle size is used, there are some problems in cleaning on the photoreceptor after image formation.
The first problem is that it is difficult to clean a toner having a spherical shape or a small particle size by using a generally used cleaning blade method. The cleaning blade moves relative to the surface of the photoconductor to remove the toner, but the edge of the cleaning blade is deformed by the frictional resistance with the photoconductor, so that there is a small space between the photoconductor and the cleaning blade. Arise. The smaller the toner particle size, the easier it is to enter this space. Then, the closer to the spherical shape the entering toner is, the smaller the rolling frictional force is. Therefore, the toner starts to roll between the photosensitive member and the cleaning blade, and passes through the cleaning blade. If a large amount of toner passes through the cleaning blade, the cleaning is poor, and an abnormal image such as a ground cover is generated.

The second problem is a so-called filming problem. In filming, while the toner that has passed through the cleaning blade continues to remain on the surface of the photoconductor, a release agent or a fluidizing agent contained in the toner becomes a causative substance and adheres to the surface of the photoconductor. Is thought to be possible. When filming is possible, an abnormal image such as a white spot on the solid portion of the image is generated.
In order to improve the cleaning performance on the photoreceptor when using the above-described spherical or small-sized toner, a lubricant made of a fatty acid metal salt or the like is applied to the photoreceptor surface to form a thin film. Patent Document 1 discloses a method for reducing the coefficient of friction on the surface of the photoreceptor. When the coefficient of friction on the surface of the photoconductor is reduced, the adhesion force acting between the photoconductor and the toner is reduced, so that cleaning with a cleaning blade is performed well and filming is also suppressed.

However, since the coefficient of friction on the surface of the photoconductor becomes too low, the adhesion force between the photoconductor and the toner becomes small, and in the development process, toner transfer from the developing roller to the electrostatic latent image formed on the photoconductor occurs. This is not sufficient, and defects such as image omission and low density images occur. For this reason, conventionally, a technique has been developed in which the amount of lubricant applied is controlled while the surface of the photoconductor is scraped with a cleaning blade or the like, and the occurrence of abnormal images is suppressed by keeping the coefficient of friction of the photoconductor surface constant. .
As a method of applying the lubricant, for example, the solidified lubricant in a stick shape is scraped off with a rotating brush, the lubricant attached to the brush is applied to the photoreceptor, and the lubricant attached to the photoreceptor is thinly stretched and fixed by a cleaning blade. The method of letting it be mentioned.

As an example of the lubricant application method, for example, a lubricant supply device (lubricant application device) described in Patent Document 2 is a lubricant supply that moves relative to the surface of the photoreceptor on the downstream side of the cleaning device. A member (brush roller), a solid lubricant that contacts the brush roller, a spring that urges the solid lubricant toward the brush roller, and a blade member that contacts the photoconductor downstream of the brush roller (leveling blade) Etc. In this configuration, the lubricant component is gradually scraped off from the solid lubricant by the brush roller rotating in a predetermined direction, and the lubricant powder scraped off by the brush roller is applied (supplied) to the surface of the photoreceptor. Thereafter, the lubricant powder supplied onto the photoreceptor is thinned (homogenized) by the blade member.
As described above, since the lubricant supply device described in Patent Document 2 is arranged on the downstream side of the cleaning device, the lubricant supply device integrally provided in the cleaning device (for example, Patent Document 2) 3), the lubricant can be stably supplied onto the photoreceptor regardless of the amount of toner cleaned by the cleaning device.
In order to keep the surface friction coefficient of the photoreceptor constant over time, it is necessary to keep the amount of lubricant applied constant over time. For this reason, several methods for keeping the pressure applied to the brush roller of the solid lubricant constant by a spring have been proposed (for example, Patent Document 4).

  By the way, as one of the important problems to be solved in the lubricant application mechanism, there is a consumption deviation in the longitudinal direction of the lubricant. This is a deviation in the consumption amount in the longitudinal direction in the process in which the solid lubricant is scraped by the brush roller. This mechanism will be described with reference to FIGS. FIG. 8 is a schematic diagram showing the structure of a conventional lubricant application brush. FIG. 9 is a schematic diagram showing a conventional lubricant application mechanism. FIG. 10 is a schematic diagram showing the operation of a conventional lubricant application device.

As shown in FIG. 8, the lubricant application brush roller 222 is configured by winding a long strip-shaped pile 222b around a metal core 222a in a spiral shape. Brush fibers are planted on the long base fabric of the strip-like pile 222b.
As shown in FIG. 9, a conventional lubricant application device 220 applies a solid lubricant 221 and a lubricant component scraped from the solid lubricant 21 by rotating in contact with the solid lubricant 221 to the photoreceptor 11. A lubricant application brush roller 222, a lubricant holding member 224 that fixes and holds the solid lubricant 221, a lubricant holder 225 that houses the solid lubricant 221 and the lubricant holding member 224, and a solid lubricant 221. A cam member 226 and an elastic member 227 are provided as pressurizing means for applying pressure to the agent application brush roller 222 side.

Due to the spiral winding of the lubricant application brush roller 222, a force is applied in the axial direction of the lubricant application brush roller 222 by the rotational force of the lubricant application brush roller 222 in the direction of arrow A (in the direction of arrow B in the figure). ). As the axial force is applied, the solid lubricant 221 gradually moves and abuts against one side plate 225a of the lubricant holder 225 holding the solid lubricant 221. Since the lubricant application brush roller 222 continues to rotate even in the abutted state, the solid lubricant 221 is pressed against the side plate 225a, and a sliding resistance is generated between the end of the solid lubricant 221 and the side plate 225a ( Arrow C) in the figure.
In the lubricant application device 220, the cam member 226 and the elastic member 227 generate pressure (arrow D in the figure) that presses the solid lubricant 221 against the lubricant application brush roller 222. However, the pressurizing force D is attenuated on the side plate 225a side where the sliding resistance C is generated (DC), and the solid lubricant 21 on the side abutting on the side plate 25a is not scraped. As shown, a consumption deviation in the longitudinal direction of the solid lubricant 221 may occur.
If there is a deviation in consumption in the longitudinal direction, the amount of lubricant applied to the photoreceptor and the photoreceptor friction coefficient will also vary in the longitudinal direction, making it impossible to maintain the desired friction coefficient and improving image quality. There is a problem that it affects. Further, if the solid lubricant 221 on the other end side is used up even though the solid lubricant 221 remains on one end portion side in the longitudinal direction due to the above deviation, solid lubrication is performed. Since it is determined that the life of the agent 221 has come, there is a problem that the use efficiency of the solid lubricant 221 is remarkably deteriorated and the life is shortened.

As means for solving the above problems, a method of adding a sliding member to the end of the lubricant holding member as in Patent Document 2, or attaching a lubricant member to the lubricant housing case as in Patent Document 3 A method for reducing sliding resistance has been proposed. However, in both cases of Patent Documents 2 and 3, since the lubricant always moves in a specific direction and does not prevent itself from striking the lubricant housing case, the sliding resistance remains. Wear will occur.
The present invention has been made in view of the above-described circumstances, and prevents uneven wear in the longitudinal direction of the solid lubricant (bias in consumption) with a simple and inexpensive component structure, and uneven application of the lubricant to the image carrier. An object of the present invention is to prevent overcoating and undercoating and prevent occurrence of uneven charging due to contamination of the charging member caused by lubricant powder at the time of overcoating and abnormal images caused by filming when undercoating.

  In order to solve the above problems, the invention described in claim 1 includes a solid lubricant and a lubricant application member that applies a lubricant component scraped from the solid lubricant by rotation to an image carrier. And a pressurizing unit that pressurizes the solid lubricant toward the lubricant application member. The pressurizing unit uniformly distributes the solid lubricant and the lubricant application unit over the entire contact surface of both. A main pressurizing means for pressurizing, and an auxiliary pressurizing means for pressurizing the solid lubricant to correct the deviation when there is a deviation along the longitudinal direction of the contact surface in the pressure applied by the main pressurizing means And.

  According to the present invention, since the auxiliary pressurizing means for correcting the deviation of the pressurizing force along the longitudinal direction is provided, uneven wear (bias of consumption) in the longitudinal direction of the solid lubricant can be prevented with a simple and inexpensive component configuration. Prevents uneven application, overcoating, and insufficient application of lubricant to the image carrier, prevents charging unevenness due to contamination of the charging member caused by lubricant powder during overapplication, and abnormalities caused by filming when application is insufficient Generation of an image can be prevented.

1 is a schematic configuration diagram of an image forming apparatus according to the present invention. It is a perspective view of a process cartridge. It is sectional drawing of a process cartridge. It is a principal part enlarged view of a process cartridge. It is a mimetic diagram showing the structure of the lubricant application device concerning one embodiment of the present invention. It is a mimetic diagram showing operation of a lubricant application device concerning one embodiment of the present invention. It is the graph which showed the relationship between the applied pressure of a lubrication agent application apparatus, and lubricant consumption. It is a schematic diagram which shows the structure of the conventional lubricant application brush. It is a schematic diagram which shows the conventional lubricant application mechanism. It is a schematic diagram which shows operation | movement of the conventional lubricant application apparatus.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The present invention is characterized in that the pressurizing means for pressurizing the solid lubricant to the lubricant applying brush roller includes an auxiliary pressurizing means for correcting a pressure deviation generated in the axial direction (longitudinal direction) of the lubricant applying brush roller. There is.
First, an outline of an image forming apparatus in which the lubricant application device according to the present invention is mounted will be described.
FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present invention. The image forming apparatus 100 is an image forming apparatus that forms a full-color image, and includes a reading unit 110 that reads a document image, an image forming unit 120 that forms a visible image on a transfer sheet, and a transfer sheet that is supplied to the image forming unit 120. The paper feeding unit 130 is mainly configured.
The reading unit 110 includes a contact glass 111 on which a document is placed, a scanning optical system 112 that scans the document and optically reads the image, and the like.
The image forming unit 120 includes four process cartridges 10 (Y, C, M, and K) corresponding to each color of yellow: Y, cyan: C, magenta: M, and black: K, and photosensitive of each process cartridge 10. An endless intermediate transfer belt 122 to which a toner image carried on the body 11 is transferred; a secondary transfer roller 123 which is disposed opposite to the intermediate transfer belt 122 and transfers the toner image on the intermediate transfer belt 122 to transfer paper; And four toner bottles 124 corresponding to the respective colors for supplying the toner to each process cartridge 10.
The process cartridge 10 will be described later.

In the drawing, the intermediate transfer belt 122 is disposed above each photoconductor 11 that is an image carrier, and the lower side of the intermediate transfer belt 122 is in contact with the outer peripheral surface of each photoconductor 11. doing. In the following, in this specification, “contacting in an abutted state” is expressed as “contact”. The intermediate transfer belt 122 functions as a transfer material on which toner images of different colors formed on the surface of each photoconductor 11 are transferred in a superimposed manner.
A primary transfer roller 125 is disposed at a position facing the photoconductor 11 with the intermediate transfer belt 122 interposed therebetween. The primary transfer roller 125 transfers the toner image formed on each photoconductor 11 to the intermediate transfer belt 122. The configuration in which a toner image is formed on each photoconductor 11 and the toner image is transferred to the intermediate transfer belt 122 is substantially the same in each process cartridge 10 except that the color of the toner image is different.
An optical writing device 60 is disposed below the row of process cartridges 10. The optical writing device 60 irradiates the uniformly charged surface of the photoreceptor 11 with a light beam, for example, a laser beam, which is optically modulated based on the image information read by the scanning optical system 112 of the reading unit 110. An electrostatic latent image is formed.
The paper feeding unit 130 includes a paper feeding cassette 131 that stores transfer paper as a recording medium, a conveyance roller 132 that feeds the transfer paper fed from the paper feeding cassette 131 toward the image forming unit 120, and an intermediate transfer belt. A registration roller pair 133 that feeds transfer paper at a predetermined timing is provided in a nip portion formed by 122 and the secondary transfer roller 123.

The process cartridge 10 will be described with reference to FIGS. FIG. 2 is a perspective view of the process cartridge. FIG. 3 is a cross-sectional view of the process cartridge. FIG. 3 is a cross-sectional view in a plane orthogonal to the axial direction.
As shown in FIG. 2, the process cartridge 10 includes a frame body 12 and side plates 13 respectively disposed at both ends in the longitudinal direction of the frame body 12. A lubricant 21 and a lubricant application brush roller 22 are installed. Both the photoconductor 11 and the lubricant application brush roller 22 are rotatably supported by two side plates 13.

As shown in FIG. 3, the process cartridge 10 includes a photoreceptor 11, a lubricant applicator 20 attached to the photoreceptor 11, a cleaning device 30, a charging device 40, and a developing device 50.
The lubricant application device 20 includes a solid lubricant 21 obtained by solidifying a lubricant made of a fatty acid metal salt or the like into a rod shape, a lubricant holding member 24 that holds the solid lubricant 21, the solid lubricant 21, and the photoreceptor 11. And a lubricant application brush roller 22 that rotates in contact with both, and a lubricant application blade 23 that contacts the surface of the photoreceptor 11.
The solid lubricant 21 is integrally held by a lubricant holding member 24, and is pressurized toward the lubricant application brush roller 22 by a pressurizing unit P (not shown), and the surface thereof contacts the lubricant application brush roller 22. doing.
The lubricant application brush roller 22 is rotated by a rotational driving force of a driving means (not shown) transmitted through a gear (not shown) arranged on one end side in the axial direction of the photoreceptor 11, and the solid lubricant 21. A powdery lubricant scraped from the toner is applied to the surface of the photoreceptor 11.
The lubricant application blade 23 levels the lubricant applied to the surface of the photoconductor 11 by the lubricant application brush roller 22 and makes the thickness uniform.

The cleaning device 30 is provided with a cleaning blade 31 that contacts the surface of the photoreceptor 11. The cleaning blade 31 cleans and collects the toner remaining on the surface of the photoconductor 11 after the toner image is transferred to the intermediate transfer belt 122.
The charging device 40 is mainly composed of a charging roller 41 disposed so as to contact the photoreceptor 11 and a charging roller cleaner 42 rotating in contact with the charging roller 41. The charging roller 41 uniformly charges the surface of the photoconductor 11, and the charging roller cleaner 42 cleans the surface of the charging roller 41.
The developing device 50 includes a developing roller 51 that supplies toner as a developer to the surface of the photoreceptor 11 to visualize the electrostatic latent image, and a mixing roller that stirs the developer stored in the developer storage unit. 52, and a supply roller 53 that supplies the stirred and mixed developer to the developing roller 51.

Hereinafter, a basic operation of the image forming apparatus 100 having such a configuration will be described.
First, the photosensitive member 11 of the process cartridge 10 is rotationally driven in the clockwise direction (arrow E direction) in FIG. 3, and the surface of the photosensitive member 11 is set to a predetermined polarity by the charging roller 41 of the charging device 40 to which a charging voltage is applied. Charge uniformly. A laser beam based on the image information of the original read by the scanning optical system 112 of the reading unit 110 is irradiated from the optical writing device 60 onto the uniformly charged surface of the photoconductor 11, and the surface of each photoconductor 11 is statically exposed. An electrostatic latent image is formed. Each color developer is supplied from the developing roller 51 of the developing device 50 to the electrostatic latent image on each photoconductor 11, and a toner image corresponding to each developer is formed to be visualized. Next, a transfer voltage is applied to the primary transfer roller 125, and the toner images on the respective photoreceptors 11 are sequentially primary transferred onto the intermediate transfer belt 122 that rotates endlessly to form a color image as a composite image. .
The transfer sheets separated one by one from the sheet feeding cassette 131 of the sheet feeding unit 130 and conveyed by the conveying roller 132 are transferred to the intermediate transfer belt 122 and the secondary transfer roller 123 by the registration roller pair 133 at a predetermined timing. To the nip formed by the The color image primarily transferred onto the intermediate transfer belt 122 is secondarily transferred onto the transfer paper fed to the nip portion. The transfer sheet on which the color image is secondarily transferred is conveyed to a fixing device 126 disposed downstream in the transfer sheet conveyance direction, and the color image on the transfer sheet is fixed by the action of heat and pressure. Next, the transfer paper on which the color image has been fixed is discharged to a paper discharge unit 142 at the top of the main body of the image forming apparatus 100 by a paper discharge roller pair 141.

On the other hand, untransferred toner adhering to the photoconductor 11 after the toner image is transferred is collected and removed by the cleaning blade 31 of the cleaning device 30 shown in FIG.
A lubricant is applied to the cleaned surface of the photoreceptor 11 by the lubricant application device 20. The solid lubricant 21 is scraped off by a lubricant application brush roller 22 that rotates in contact with both the solid lubricant 21 and the photoconductor 11, and the pulverized lubricant is applied to the surface of the photoconductor 11. .
The lubricant applied to the surface of the photoreceptor 11 is leveled by the lubricant application blade 23 and the thickness thereof is made uniform. The photosensitive member 11 coated with the lubricant is uniformly charged to a predetermined polarity by the charging roller 41 of the charging device 40, and thereafter, the same operation is repeated and the image forming process is repeated.

Now, a lubricant application device according to an embodiment of the present invention will be described with reference to FIGS. FIG. 4 is an enlarged view of a main part of the process cartridge shown in FIG. 3, and is an enlarged cross-sectional view of a lubricant application device portion. FIG. 5 is a schematic view showing the structure of a lubricant application device according to an embodiment of the present invention.
The lubricant application device 20 includes a solid lubricant 21, a lubricant application brush roller 22 (lubricant application member) that applies a lubricant component that has been scraped off from the solid lubricant 21 by rotation, and a photosensitive agent. Lubricant application blade 23 for leveling the lubricant applied to the surface of the body 11 to make the thickness uniform, a lubricant holding member 24 for fixing and holding the solid lubricant 21, the solid lubricant 21 and the lubricant A lubricant holder 25 that accommodates the holding member 24 and pressurizing means P that pressurizes the solid lubricant 21 toward the lubricant application brush roller 22 are provided. The pressurizing means P includes main pressurizing means P1 (cam member 26 and elastic member 27) and auxiliary pressurizing means P2 (pressurizing member 29).

The lubricant application brush roller 22 includes a metal cored bar 22a and a long strip-shaped pile 22b wound around the cored bar 22a in a spiral shape. Brush fibers are planted on the base fabric of the strip-like pile 22b, and the configuration is the same as that of a conventional lubricant application brush roller (see FIG. 8). As the lubricant application brush roller 22 rotates, the lubricant component is scraped or scraped off from the solid lubricant 21 with the brush fiber and applied to the photoreceptor 11.
As shown in FIG. 4, the lubricant holding member 24 is accommodated in the thickness direction so as to be slidable in contact with guide surfaces 25 g of the lubricant holder 25 facing each other, and the lubricant holding member 24 is solid lubricated. The agent 21 is held movably in the thickness direction.

The main pressurizing means P1 will be described. The main pressurizing means P1 includes a pair of cam members 26 that are rotatably supported by the lubricant holding member 24 within a predetermined angle range, and an elastic member 27 that urges the two cam members 26 with an elastic force. Then, it operates so as to supply a predetermined amount of lubricant to the photoconductor 11.
The pair of cam members 26 has a predetermined distance between the lubricant holding member 24 and the bottom 25b of the lubricant holder 25 facing the lubricant holding member 24 at a target position with the central portion in the longitudinal direction as the center. Arranged. One end portion of the cam member 26 is rotatably supported by the lubricant holding member 24 by the rotating shaft 26a, and the other end portion 26b is in sliding contact with the bottom portion 25b of the lubricant holder 25 facing the lubricant holding member 24. doing. The other end portion 26 b is formed in an arc shape, and the distance between the bottom portion 25 b and the lubricant holding member 24 is changed by changing the rotation angle of the cam member 26.
An elastic member 27 that elastically urges the cam members 26 toward each other is attached between the cam members 26. The elastic member 27 urges both the cam members 26 to bring the solid lubricant 21 into pressure contact with the lubricant application brush roller 22.

FIG. 5 shows a tension spring as an example of the elastic member 27. The tension spring exerts a restoring force that acts to narrow the interval between the cam members 26. With this restoring force, both cam members 26 are gradually raised in accordance with the remaining amount of the solid lubricant 21, and both cam members 26 are pressed against the bottom 25 b of the lubricant holder 25. The solid lubricant 21 supported by the lubricant holding member 24 is always in contact with the lubricant application brush roller 22 at a predetermined pressure (pressurizing force F) using the reaction force from the bottom 25b. Has been.
The two cam members 26 receive the urging force of the elastic member 27 and press the bottom portion 25 b with an equal force, and the solid lubricant 21 is pressed against the lubricant application brush roller 22. The main pressurizing means P1 pressurizes the lubricant holding member 24 with the rotation shafts 26a of the cam member 26, which are two symmetrical places around the central portion in the longitudinal direction of the lubricant holding member 24, as the pressurizing position. By this pressurization, the solid lubricant 21 is uniformly pressed against the lubricant application brush roller 22 over the entire contact surfaces in the longitudinal direction.
In addition, you may use the other elastic material (rubber etc.) which carries out the same function as the said tension spring.

Further, a pressurizing member 29 (29a, 29b) for pressurizing the lubricant holding member 24 is disposed as an auxiliary pressurizing unit P2 outside the main pressurizing unit P1 in the longitudinal direction. The auxiliary pressurizing unit P2 pressurizes a portion of the lubricant holding member 24 located on the outer side in the longitudinal direction of the rotating shaft 26a, which is a pressurizing position by the main pressurizing unit P1. FIG. 5 shows a compression spring as an example of the pressure member 29. The compression spring is installed so as to stand vertically from the bottom portion 25 b toward the lubricant holding member 24. The pressurizing member 29 is configured to always press the solid lubricant 21 against the lubricant application brush roller 22 by a reaction force (pressurizing force G: Ga, Gb) from the bottom portion 25b. That is, the pressurizing member 29 pressurizes the lubricant holding member 24 so as to push up vertically from the bottom portion 25 b of the lubricant holder 25.
The pressure G by the pressure member 29 is set to be smaller than the pressure F by the elastic member 27. The pressurizing member 29 serves to adjust the pressure in the longitudinal direction mainly to prevent uneven wear in the longitudinal direction of the contact surface of the solid lubricant 21. That is, the pressure member 29 corrects this deviation when there is a deviation along the longitudinal direction of the contact surface between the solid lubricant 21 and the lubricant application brush roller 22 with respect to the pressure applied by the main pressure means P1.

Hereinafter, the operation of the lubricant application device according to the present invention will be described with reference to FIG. FIG. 6 is a schematic view showing the operation of the lubricant application device according to the embodiment of the present invention.
It is assumed that a deviation occurs between the ends in the longitudinal direction with respect to the pressure applied to the lubricant application brush roller 22 by the solid lubricant 21, and uneven wear occurs in the solid lubricant 21. At this time, in the case of the conventional lubricant application device 220 (see FIG. 10), the solid lubricant 221 and the lubricant holding member 224 abut on the side plate 225a on the one end side in the longitudinal direction of the lubricant holder 225, whereby the side plate 225a. On the side, the applied pressure based on the cam member 226 and the elastic member 227 (corresponding to the main pressurizing means P1), in other words, the applied pressure of the solid lubricant 221 against the lubricant application brush roller 222 is attenuated. If uneven wear does not occur, the applied pressure from the cam member 226 and the elastic member 227 is uniform in the longitudinal direction.

In the present invention, as shown in FIG. 6, when a deviation occurs in the amount of consumption of the solid lubricant 21 in the longitudinal direction due to the characteristics of the pressure members 29a and 29b, the pressure members 29a and 29b have a deviation in compression amount. As a result, a deviation of the applied pressure G is also generated between the pressure members 29a and 29b. That is, when the pressing force of the pressing member 29a is Ga and the pressing force of the pressing member 29b is Gb, the pressing member 29a side where the consumption amount of the solid lubricant 21 is large and the pressing member 29b side where the consumption amount is small are applied. The pressure relationship is Ga <Gb. Further, due to the characteristics of the compression spring, the greater the amount of compression, the greater the applied pressure. Therefore, the greater the deviation in consumption, the greater the difference in applied pressure between Ga and Gb.
Therefore, the difference between the pressurizing forces Ga and Gb in the longitudinal direction is such that the pressurizing force to the solid lubricant 21 increases as the consumption amount of the solid lubricant 21 decreases. The consumption deviation of the lubricant can be corrected so as to increase, and the deviation of the consumption amount in the longitudinal direction can be corrected.

FIG. 7 is a graph showing the relationship between the pressure applied by the lubricant application device and the amount of lubricant consumed.
Since a compression spring is used for the pressure member 29, the pressure G applied to the lubricant decreases as the consumption amount of the solid lubricant 21 increases. The profile of the pressing force is determined by the spring constant of the compression spring used for the pressing member 29 and the consumption amount of the solid lubricant 21.
On the other hand, the profile of the pressure F of the main pressurizing means P1 can be changed according to the shape (cam shape) of the other end portion 26b of the cam member 26. In other words, the applied pressure F can be changed according to the amount of consumption of the solid lubricant 21 by changing the shape of the other end portion 26b.
In the present invention, the shape of the other end portion 26b of the cam member 26 is set so that the sum of the pressurizing force F of the main pressurizing means P1 and the pressurizing force G of the auxiliary pressurizing means P2 is constant. The decrease in the pressure G of the pressure means P2 is supplemented by the pressure F of the main pressure means P1. Therefore, the applied pressure F + G of the solid lubricant 21 to the lubricant application brush roller 22, that is, the total F + G of the applied pressure F of the main pressurizing means P1 and the applied pressure G of the auxiliary pressurizing means P2 is set to a desired value over time. Can be kept constant.
If uneven wear occurs in the longitudinal direction of the solid lubricant, the auxiliary pressurizing means P2 consumes a small amount of lubricant with respect to the applied pressure on the side where the amount of consumption is large (the remaining amount of lubricant is small). Since the pressing force on the side with a large remaining amount is set to increase, the pressing force can be corrected by the auxiliary pressurizing means P2 so that the lubricant consumption amount is uniform in the longitudinal direction.

As described above, according to the present invention, the auxiliary pressurizing means for correcting the deviation along the longitudinal direction is provided, so that uneven wear of the lubricant in the longitudinal direction is prevented, and uneven application of the lubricant to the photosensitive member is caused. Application and insufficient application can be prevented, and charging unevenness due to contamination of the charging member generated by the lubricant powder at the time of excessive application and abnormal images generated by filming when application is insufficient can be prevented. Further, since the auxiliary pressurizing means P2 can be composed of, for example, a compression spring, it is possible to prevent uneven wear in the longitudinal direction of the lubricant with a simple and inexpensive component structure.
In the above description, the process cartridge is described as an example in which the photosensitive member and the lubricant application device are provided in the process cartridge. However, the present invention may be applied to an image forming apparatus that does not include the process cartridge. Is possible.
The present invention is not limited to the embodiments described above, and many variations can be implemented by those having ordinary knowledge in the art within the technical idea of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Process cartridge, 11 ... Photoconductor, 12 ... Frame, 13 ... Side plate, 20 ... Lubricant application apparatus, 21 ... Solid lubricant, 22 ... Lubricant application brush roller (lubricant application member), 22a ... Core metal 22b ... strip pile, 23 ... lubricant application blade, 24 ... lubricant holding member, 25 ... lubricant holder, P ... pressurizing means, P1 ... main pressurizing means, 26 ... cam member, 27 ... elastic member, P2: auxiliary pressure means, 29, 29a, 29b ... pressure member, 30 ... cleaning device, 31 ... cleaning blade, 40 ... charging device, 41 ... charging roller, 42 ... charging roller cleaner, 50 ... developing device, 51 ... Developing roller 52 ... Mixing roller 53 ... Supply roller 60 ... Optical writing device 100 ... Image forming device 110 ... Reading unit 120 ... Image forming unit 122 ... Intermediate transfer belt 1 3 ... Secondary transfer roller, 124 ... Toner bottle, 125 ... Primary transfer roller, 126 ... Fixing device, 130 ... Paper feed unit, 131 ... Paper feed cassette, 132 ... Conveyance roller, 133 ... Registration roller pair, 141 ... Paper discharge Roller pair, 142 ... paper discharge unit, 220 ... lubricant application device, 221 ... solid lubricant, 222 ... lubricant application brush roller, 224 ... lubricant holding member, 225 ... lubricant holder, 226 ... cam member, 227 ... Elastic member

JP 2002-287567 A JP 2007-140391 A JP 2006-349704 A JP 2007-293240 A JP 2007-298948 A JP 2007-219506 A

Claims (5)

Solid lubricant,
A lubricant application member that applies the lubricant component scraped off from the solid lubricant by rotation to the image carrier;
Pressurizing means for pressurizing the solid lubricant to the lubricant application member side,
The pressurizing unit includes a main pressurizing unit that uniformly pressurizes the solid lubricant and the lubricant applying unit over the entire contact surface thereof, and a pressure applied to the contact surface by the main pressurizing unit. An auxiliary pressurizing unit that pressurizes the solid lubricant to correct the deviation when there is a deviation along the longitudinal direction. A lubricant holding member that holds the solid lubricant and is movable in the thickness direction thereof,
The main pressurizing means pressurizes at least two symmetrical places around the longitudinal center of the lubricant holding member,
The said auxiliary pressurization means is a compression spring which pressurizes the site | part of the said lubricant holding member located in the longitudinal direction outer side of the two pressurization positions by the said main pressurization means. Lubricant application equipment. A lubricant holding member for holding the solid lubricant;
A lubricant holder for accommodating the solid lubricant and the lubricant holding member,
One end of the main pressurizing means is rotatably supported in a predetermined angular range at the two pressurization positions of the lubricant holding member, and the other end faces the lubricant holding member. Two cam members that contact the bottom of the lubricant holder in a sliding state and change a distance between the bottom and the lubricant holding member by changing a rotation angle;
An elastic member that pressurizes each of the cam members to bring the solid lubricant into pressure contact with the lubricant application member, and
The shape of the other end of each cam member is set so that the sum of the pressurizing forces of the main pressurizing means and the auxiliary pressurizing means is constant. The lubricant application device described.   A process cartridge comprising the lubricant application device according to any one of claims 1 to 3.   An image forming apparatus comprising the lubricant application device according to claim 1 or the process cartridge according to claim 4.

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