JP2012073527A - Cover member, lubricant supply device, process cartridge, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cover member that has a relatively small number of parts and covers multiple corners for protection, a lubricant supply device, a process cartridge, and an image forming apparatus.SOLUTION: A cover member 16f is formed by bending a sheet metal into a box shape and raising four side faces 16f2 to 16f4 with respective four sides of a base surface 16f1 as bending portions. A fitting member 16f6 is provided so as to fit the cover member 16f by externally covering two corners 16f21, 16f31 that are formed on a side face 16f3 side that is adjacent to two opposing side faces 16f2, 16f3 of four side faces.

Description

  The present invention relates to a cover member formed into a box shape by bending a sheet metal into a box, and a lubricant supply device, a process cartridge, and an image forming apparatus provided with the cover member.

Conventionally, a cover member (machine case) formed in a box shape by bending a sheet metal into a box is known (see, for example, Patent Documents 1 and 2). Specifically, the cover member is formed so that four sides of the base surface stand up with the four sides of the base surface as bending sources, respectively, by subjecting the sheet metal to box bending.
Further, in Patent Documents 1 and 2 and the like, in the cover member, four protective members (corner members) made of resin for covering and protecting a corner portion (corner portion) where two adjacent side surfaces and the base surface meet each other are protected. A technique for installing at a corner is disclosed.

On the other hand, in an image forming apparatus using an electrophotographic system such as a copying machine, a printer, a facsimile, or a composite machine thereof, a lubricant supply for supplying a lubricant onto an image carrier such as a photosensitive drum or an intermediate transfer belt. A technique using an apparatus is known (see, for example, Patent Documents 3 and 4).
Specifically, the lubricant supply device biases a brush roller (brush-like rotating member) that is in sliding contact with the photosensitive drum (image carrier), a solid lubricant that is in contact with the brush roller, and a solid lubricant toward the brush roller. It is composed of a spring (biasing member) and the like. Then, the lubricant is gradually scraped off from the solid lubricant by the brush roller rotating in a predetermined direction, and the lubricant scraped off and transported by the brush roller is applied (supplied) to the surface of the image carrier.
In such a lubricant supply device, the cover member can be attached to and detached from the device so that the solid lubricant enters the inside of the cover member via a spring in order to easily perform maintenance for replacing the solid lubricant. Many of them have been used.

  Since the conventional cover member is made of a metal material, it has a merit that it is stronger and less deformed even when a large load is applied compared to a resin material. . However, in the cover member, sharp edges and burrs are generated by box bending at the corners where the two adjacent side surfaces and the base surface meet. There was a high possibility of it.

  In order to solve such a problem, in Patent Documents 1 and 2, a resin protective member (corner member) is installed on the cover member so as to cover the four corners, but the number of parts of the protective member is small. It was a lot. Such a problem is that in the cover member in which the rising angles of the four side surfaces that stand up with respect to the base surface are not constant, the shape of the protective member that covers the four corners is different, and the protective member is a common component. Since it can no longer be converted, it cannot be ignored.

  In addition, the cover member used in the lubricant supply device is often installed in a space with a complicated shape that saves space in the device, and as described above, the four side surfaces stand up with respect to the base surface. Since many are not used with a constant angle, it is highly necessary to simply configure a protective member that covers the four corners.

  The present invention has been made to solve the above-mentioned problems, and has a cover member, a lubricant supply device, and a process cartridge that have a relatively small number of parts and can cover and protect a plurality of corners. And providing an image forming apparatus.

  The cover member according to the first aspect of the present invention is a cover member in which four side surfaces of the base surface are raised by bending each of the four sides of the base surface by box bending the sheet metal. The fitting member which fits so that two corner | angular parts formed in the side of at least one side surface among the two side surfaces which adjoin among two side surfaces which oppose among side surfaces may be installed from the outer side is installed.

  According to a second aspect of the present invention, in the cover member according to the first aspect, the fitting member is fitted so as to sandwich both end portions of the side surface from the inside of the at least one side surface. A concave portion and an outer edge portion formed in a range exceeding the width of the one side surface so as to cover from the outside from the corner portion to each edge portion on the two opposing side surfaces.

  According to a third aspect of the present invention, in the cover member according to the second aspect, the concave portion of the fitting member is fitted into a positioning hole formed on the at least one side surface. A boss portion is formed.

  According to a fourth aspect of the present invention, there is provided the cover member according to the third aspect, wherein the fitting member is cantilevered at a portion where the boss portion is formed. It is formed.

  Moreover, the cover member concerning invention of Claim 5 made the said fitting member into the plate-shaped member formed with the polymeric compound in the invention in any one of the said Claims 1-4. Is.

  A lubricant supply device according to a sixth aspect of the present invention is a lubricant supply device that supplies a lubricant onto an image carrier on which a toner image is carried. A brush-like rotating member that rotates in a predetermined direction and has brush bristles that slidably contact the image carrier, and a solid member that slidably contacts the brush bristles of the brush-like rotating member. A lubricant, and a biasing member that biases the solid lubricant toward the brush-like rotating member, and the cover member includes a part of the solid lubricant via the biasing member therein. Or it is installed so that attachment or detachment is possible with respect to an apparatus so that all may enter.

  A process cartridge according to a seventh aspect of the present invention is a process cartridge that is detachably installed on a main body of the image forming apparatus, and the lubricant supply device according to the sixth aspect and the image carrier It has a body.

  An image forming apparatus according to an eighth aspect of the present invention includes the lubricant supply device according to the sixth aspect and the image carrier.

  In the present application, the “process cartridge” refers to a charging unit that charges the image carrier, a developing unit (developing device) that develops a latent image formed on the image carrier, and a cleaning on the image carrier. At least one of the cleaning units and the image carrier are defined as a unit that is integrated and detachably installed on the image forming apparatus main body.

  In the present invention, since the fitting member that fits the two corners from the outside is installed in the cover member, the number of parts is relatively small, and the plurality of corners are covered and protected. A cover member, a lubricant supply device, a process cartridge, and an image forming apparatus can be provided.

1 is an overall configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. It is a block diagram which shows the image formation part for black. It is a block diagram which shows the color image creation part. It is a perspective view which shows a cover member. It is a top view which shows a cover member. It is a perspective view which shows the cover member of the state from which the fitting member was taken out. It is a front view which shows the fitting member of another form. It is a top view which shows the state by which the fitting member of FIG. 7 is installed in a cover member.

Embodiment.
Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

First, the configuration and operation of the entire image forming apparatus will be described with reference to FIG.
The image forming apparatus 1 according to the present embodiment is a tandem color image forming apparatus in which process cartridges 10Y, 10M, 10C, and 10BK as a plurality of image forming units are arranged in parallel so as to face the intermediate transfer belt 17. .

  In FIG. 1, 1 is an apparatus main body of a color copying machine as an image forming apparatus, 3 is a document conveying unit that conveys a document to a document reading unit 4, 4 is a document reading unit that reads image information of a document, and 6 is input image information. A writing unit (exposure unit) that emits laser light based on the above, 7 is a paper feeding unit that accommodates a recording medium P such as transfer paper, and 10Y, 10M, 10C, and 10BK are colors (yellow, magenta, cyan, and black). A process cartridge as a corresponding image forming unit, 17 is an intermediate transfer belt on which toner images of a plurality of colors are transferred in an overlapping manner, and 18 is a secondary transfer that transfers a toner image formed on the intermediate transfer belt 17 to a recording medium P. A roller, 20 a fixing unit for fixing an unfixed image on the recording medium P, and 28 a toner for each color is supplied to the developing unit of each process cartridge (image forming unit) 10Y, 10M, 10C, 10BK. Toner container of the eye, showing the.

Here, each of the process cartridges 10Y, 10M, 10C, and 10BK (image forming unit) includes a photosensitive drum 11 as an image carrier, a charging unit 12, a developing unit 13 (developing device), and a cleaning unit 15 (cleaning device). ), The lubricant supply device 16 (lubricant supply unit) is integrated (see FIGS. 2 and 3). The process cartridges 10Y, 10M, 10C, and 10BK are replaced with the apparatus main body 1 when the lifetime is reached.
A toner image of each color (yellow, magenta, cyan, black) is formed on the photosensitive drum 11 (image carrier) in each of the process cartridges 10Y, 10M, 10C, and 10BK.

Hereinafter, an operation during normal color image formation in the image forming apparatus will be described.
First, the document is transported from the document table by the transport rollers of the document transport unit 3 and placed on the contact glass of the document reading unit 4. Then, the document reading unit 4 optically reads the image information of the document placed on the contact glass.
Specifically, the document reading unit 4 scans an image of a document on the contact glass while irradiating light emitted from an illumination lamp. Then, the light reflected from the original is imaged on the color sensor via the mirror group and the lens. The color image information of the original is read for each color separation light of RGB (red, green, blue) by the color sensor, and then converted into an electrical image signal. Further, an image processing unit (not shown) performs color conversion processing, color correction processing, spatial frequency correction processing, and the like on the basis of RGB color separation image signals, so that yellow, magenta, cyan, and black are processed. Get color image information.

  Then, image information of each color of yellow, magenta, cyan, and black is transmitted to the writing unit 6. Then, laser light (exposure light) based on the image information of each color is emitted from the writing unit 6 toward the photosensitive drums 11 of the corresponding process cartridges 10Y, 10M, 10C, and 10BK, respectively.

On the other hand, the four photosensitive drums 11 rotate in the clockwise direction in the figure. First, the surface of the photosensitive drum 11 is uniformly charged at a position facing the charging roller 12a (charging unit 12) (this is a charging process). Thus, a charged potential is formed on the photosensitive drum 11. Thereafter, the surface of the charged photosensitive drum 11 reaches the irradiation position of each laser beam.
In the writing unit 6, laser light corresponding to the image signal is emitted from the light source corresponding to each color. Although not shown, the laser light is incident on the polygon mirror and reflected, and then passes through a plurality of lenses. The laser light after passing through the plurality of lenses passes through different optical paths for each of the yellow, magenta, cyan, and black color components (this is an exposure process).

  Laser light corresponding to the yellow component is irradiated onto the surface of the photosensitive drum 11 of the first process cartridge 10Y from the left side of the drawing. At this time, the yellow component laser light is scanned in the rotational axis direction (main scanning direction) of the photosensitive drum 11 by a polygon mirror (not shown) that rotates at high speed. Thus, an electrostatic latent image corresponding to the yellow component is formed on the photosensitive drum 11 after being charged by the charging roller 12a.

  Similarly, the cyan component laser light is applied to the surface of the photosensitive drum 11 of the second process cartridge 10 </ b> C from the left side of the sheet, thereby forming an electrostatic latent image of the cyan component. The laser beam corresponding to the magenta component is irradiated onto the surface of the photosensitive drum 11 of the third process cartridge 10M from the left side of the paper, and an electrostatic latent image corresponding to the magenta component is formed. The black component laser light is applied to the surface of the photosensitive drum 11 of the process cartridge 10BK (black image forming unit), which is fourth from the left side of the drawing (the most downstream side with respect to the traveling direction of the intermediate transfer belt 17). Thus, an electrostatic latent image of the black component is formed.

Thereafter, the surface of the photosensitive drum 11 on which the electrostatic latent image of each color is formed reaches a position facing the developing unit 13. Then, each color toner is supplied from each developing unit 13 onto the photosensitive drum 11, and the latent image on the photosensitive drum 11 is developed (this is a developing step).
Thereafter, the surface of the photosensitive drum 11 after the development process reaches a position facing the intermediate transfer belt 17. Here, a primary transfer roller 14 is installed at each facing position so as to contact the inner peripheral surface of the intermediate transfer belt 17. Then, at the position of the primary transfer roller 14, the toner images of the respective colors formed on the photosensitive drum 11 are sequentially transferred onto the intermediate transfer belt 17 (first transfer process).

Then, the surface of the photosensitive drum 11 after the first transfer process reaches a position facing the cleaning unit 15. The untransferred toner remaining on the photosensitive drum 11 is collected by the cleaning unit 15 (this is a cleaning process).
Thereafter, the surface of the photosensitive drum 11 sequentially passes through the position of the lubricant supply device 16 and the position of the charge eliminating unit (not shown), and a series of image forming processes on the photosensitive drum 11 is completed.

On the other hand, the surface of the intermediate transfer belt 17 on which the images of the respective colors on the photosensitive drum 11 are transferred in an overlapping manner travels in the direction of the arrow in the drawing and reaches the position of the secondary transfer roller 18. Then, the full color image on the intermediate transfer belt 17 is secondarily transferred onto the recording medium P at the position of the secondary transfer roller 18 (second transfer step).
Thereafter, the surface of the intermediate transfer belt 17 reaches the position of an intermediate transfer belt cleaning unit (not shown). The untransferred toner on the intermediate transfer belt 17 is collected by the intermediate transfer belt cleaning unit, and a series of transfer processes on the intermediate transfer belt 17 is completed.

Here, the recording medium P at the position of the secondary transfer roller 18 is conveyed from the paper supply unit 7 via the conveyance guide, the registration roller 19 and the like.
Specifically, the transfer paper P fed by the paper feed roller 8 from the paper feed unit 7 that stores the recording medium P is guided to the registration roller 19 after passing through the conveyance guide. The recording medium P that has reached the registration roller 19 is conveyed toward the position of the secondary transfer roller 18 in synchronization with the toner image on the intermediate transfer belt 17.

Thereafter, the recording medium P on which the full-color image is transferred is guided to the fixing unit 20. In the fixing unit 20, the color image is fixed on the recording medium P at the nip between the fixing roller and the pressure roller.
The recording medium P after the fixing step is discharged as an output image outside the apparatus main body 1 by the paper discharge roller 29 and then stacked on the paper discharge unit 5 to complete a series of image forming processes.

Although not shown, the image forming apparatus 1 according to the present embodiment includes the color process cartridges 10Y, 10M, and 10C photosensitive drums 11 (excluding the monochrome process cartridge 10BK photosensitive drum 11). The primary transfer roller 14 that is in contact with the three color photosensitive drums 11 is provided with an intermediate transfer belt 17 and a contact / separation mechanism that can move freely with respect to the photosensitive drum 11. .
When a monochrome image is formed, the contact / separation mechanism operates to separate the three primary transfer rollers 14 from the three color photosensitive drums 11, and the intermediate transfer belt 17 is moved to the monochrome process cartridge. Only the 10BK photosensitive drum 11 is brought into contact. As described above, the monochrome process cartridge 10BK (black image forming unit) often has a high proportion of black in an image when forming a color image, and also when forming a monochrome image. In general, the frequency of use (operating rate) is higher than that of the color process cartridges 10Y, 10M, and 10C.

Next, the image forming unit of the image forming apparatus will be described in detail with reference to FIGS.
2 is a configuration diagram showing a process cartridge 10BK (monochrome process cartridge) as a black image forming unit. FIG. 3 shows process cartridges 10Y, 10M, and 10C (color printers) as other image forming units. FIG. The monochrome process cartridge 10BK and the color process cartridges 10Y, 10M, and 10C are different except that the color of the toner used in the image forming process is different and the size of the solid lubricant 16b is different. It is comprised by the substantially same component.

  As shown in FIGS. 2 and 3, the process cartridges 10Y, 10M, 10C, and 10BK include a photosensitive drum 11 as an image carrier, a charging unit 12 that charges the photosensitive drum 11, and the photosensitive drum 11 A developing unit 13 that develops an electrostatic latent image formed on the photosensitive drum 11, a cleaning unit 15 that collects untransferred toner on the photosensitive drum 11, and a lubricant supply device 16 that supplies a lubricant to the photosensitive drum 11. Are housed integrally in the case.

Here, the photosensitive drum 11 as an image bearing member is a negatively charged organic photosensitive member, and a photosensitive layer or the like is provided on a drum-shaped conductive support.
Although not shown, the photosensitive drum 11 has an undercoat layer that is an insulating layer, a charge generation layer and a charge transport layer as a photosensitive layer, and a protective layer (surface layer) in this order on a conductive support as a base layer. Are stacked.
As the conductive support (base layer) of the photosensitive drum 11, a conductive material having a volume resistance of 10 ¹⁰ Ωcm or less can be used.

The charging unit 12 includes a charging roller 12a, a cleaning roller 12b, and the like. The charging roller 12 a is a roller member formed by coating an outer periphery of a conductive metal core with a medium-resistance elastic layer, and is disposed on the downstream side in the rotation direction of the photosensitive drum 11 with respect to the lubricant supply device 16. Yes. Further, the charging roller 12a is disposed so as to face the photosensitive drum 11 in a non-contact manner so that the lubricant supplied onto the photosensitive drum 11 by the lubricant supply device 16 does not adhere. The cleaning roller 12b is for removing dirt on the charging roller 12a, and is disposed so as to contact the charging roller 12a.
In the charging unit 12 configured as described above, a predetermined voltage is applied to the charging roller 12a from a power supply unit (not shown), thereby uniformly charging the surface of the photosensitive drum 11 facing the charging roller 12a.

  The developing unit (developing device) 13 mainly includes a developing roller 13a that faces the photosensitive drum 11, a first transport screw 13b1 that faces the developing roller 13a, and a first transport screw 13b1 that faces the first transport screw 13b1 via a partition member. It is comprised by the 2 conveyance screw 13b2 and the doctor blade 13c facing the developing roller 13a. The developing roller 13a includes a magnet that is fixed inside and forms a magnetic pole on the peripheral surface of the roller, and a sleeve that rotates around the magnet. A plurality of magnetic poles are formed on the developing roller 13a (sleeve) by the magnet, and the developer is carried on the developing roller 13a.

In the developing unit 13, a two-component developer composed of a carrier and a toner is accommodated.
As the toner, spherical toner having a circularity of 0.98 or more is used to improve the image quality. The “circularity” is an average circularity measured by a flow type particle image analyzer “FPIA-2000” (manufactured by Toa Medical Electronics Co., Ltd.). Specifically, 0.1 to 0.5 ml of a surfactant (preferably an alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance. Further, about 0.1 to 0.5 g of a measurement sample (toner) is added. Thereafter, the suspension in which the toner is dispersed is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the dispersion liquid concentration is set to 3000 to 10000 / μl in the above-described analyzer. Then, the shape and distribution of the toner are measured.

As the spherical toner, it is possible to use an irregularly shaped toner (pulverized toner) whose shape is distorted by a pulverization method that has been widely used so far, which is spheroidized by heat treatment or the like, or a toner manufactured by a polymerization method. it can.
When such a spherical toner is used, conventionally, there is a case in which a slight gap between the cleaning blade 15a and the photosensitive drum 11 enters the gap and eventually passes through the gap, resulting in poor cleaning. However, in the present embodiment, a lubricant is applied to the surface of the photosensitive drum 11 by the lubricant supply device 16 to improve the toner peelability (removability) on the photosensitive drum 11, so that a cleaning failure occurs. Is suppressed.

  The cleaning unit 15 is disposed on the upstream side in the rotation direction of the photosensitive drum 11 with respect to the lubricant supply device 16. The cleaning unit 15 includes a cleaning blade 15a that is in contact with the photosensitive drum 11, a transport coil 15b that transports the toner collected in the cleaning unit 15 as waste toner toward a waste toner collection container (not shown). Etc. are installed. The cleaning blade 15a is made of a rubber material such as urethane rubber, and is in contact with the surface of the photosensitive drum 11 at a predetermined angle and a predetermined pressure. As a result, deposits such as untransferred toner adhering to the photosensitive drum 11 are mechanically scraped and collected in the cleaning unit 15. Here, examples of the deposit that adheres to the photosensitive drum 11 include untransferred toner, paper dust generated from the recording medium P (paper), and a discharge product generated on the photosensitive drum 11 when discharged by the charging roller 12a. And additives added to the toner.

The lubricant supply device 16 includes a solid lubricant 16b, a brush-like rotating member 16a around which brush bristles that are in sliding contact with the photosensitive drum 11 and the solid lubricant 16b, and a solid lubricant 16b directed toward the brush-like rotating member 16a. A compression spring 16c as an urging member for urging the blade, a blade-like member 16d for thinning the lubricant supplied onto the photosensitive drum 11 by the brush-like rotating member 16a, and a holder for holding the side surface of the solid lubricant 16b 16e, a cover member 16f that covers a part of the lubricant supply device 16, and the like. The blade-like member 16d is configured to contact the photosensitive drum 11 in the counter direction at a position downstream of the brush-like rotating member 16a in the rotation direction of the photosensitive drum 11.
The lubricant supply device 16 configured as described above supplies the thinned lubricant on the photosensitive drum 11. The configuration and operation of the lubricant supply device 16 will be described in detail later.

The image forming process described above will be described in more detail with reference to FIG.
The developing roller 13a rotates in the arrow direction (counterclockwise direction) in FIGS. The developer in the developing unit 13 is replenished from the toner container 28 by a toner replenishing unit (not shown) by the rotation of the first transport screw 13b1 and the second transport screw 13b2 that are disposed so as to interpose a partition member therebetween. The toner circulates in the longitudinal direction while being agitated and mixed with the toner (the direction perpendicular to the paper surface in FIGS. 2 and 3).

  The toner that is frictionally charged and adsorbed on the carrier is carried on the developing roller 13a together with the carrier. The developer carried on the developing roller 13a then reaches the position of the doctor blade 13c. The developer on the developing roller 13a is adjusted to an appropriate amount at the position of the doctor blade 13c and then reaches a position facing the photosensitive drum 11 (development region).

  Thereafter, in the developing region, the toner in the developer adheres to the electrostatic latent image formed on the surface of the photosensitive drum 11. Specifically, the latent image potential (exposure potential) of the image portion irradiated with the laser beam L and the electric field formed by the potential difference (development potential) between the development bias applied to the developing roller 13a cause the toner to become a latent image. (Toner image is formed).

  Thereafter, most of the toner adhering to the photosensitive drum 11 in the developing process is transferred onto the intermediate transfer belt 17. The untransferred toner remaining on the photosensitive drum 11 is collected in the cleaning unit 15 by the cleaning blade 15a.

  Here, although not shown in the figure, the toner replenishing portion provided in the apparatus main body 1 includes a bottle-shaped toner container 28 configured to be replaceable, and holds and rotates the toner container 28, and the developing unit 13 is newly installed. And a toner hopper for replenishing toner. Also, a new toner (any one of yellow, magenta, cyan, and black) is accommodated in the toner container 28. In addition, a spiral protrusion is formed on the inner peripheral surface of the toner container 28 (toner bottle).

  The new toner in the toner container 28 is appropriately supplied from the toner supply port into the developing unit 13 as the toner in the developing unit 13 (existing toner) is consumed. Although illustration is omitted, the consumption of toner in the developing unit 13 is indirectly caused by a reflection type photosensor facing the photosensitive drum 11 and a magnetic sensor installed below the second conveying screw 23b2 of the developing unit 13. Or detected directly.

Hereinafter, the configuration and operation of the lubricant supply device 16 (lubricant supply unit) in the present embodiment will be described in detail.
As shown in FIGS. 2 and 3, the lubricant supply device 16 includes a solid lubricant 16b, a brush-like rotating member 16a (brush-like) around which brush bristles slidingly contact the photosensitive drum 11 and the solid lubricant 16b are provided. Roller), a compression spring 16c as a biasing member that biases the solid lubricant 16b toward the brush-like rotating member 16a, and the lubricant supplied onto the photosensitive drum 11 by the brush-like rotating member 16a is thinned. The blade-shaped member 16d, a holder 16e that holds the side surface of the solid lubricant 16b, a cover member 16f that covers a part of the lubricant supply device 16, and the like.

The brush-like rotating member 16a has a spiral shape on a core bar in which brush hairs having a length (hair feet) in the range of 0.2 to 20 mm (preferably 0.5 to 10 mm) are planted on a base cloth. It is wrapped around.
When the length of the bristle exceeds 20 mm, the bristle falls in a predetermined direction due to repeated rubbing with the photosensitive drum 11 over time, and the scraping property of the solid lubricant 16b or from the photosensitive drum 11 is reduced. Toner removability is reduced. On the other hand, if the length of the bristle is less than 0.2 mm, the physical contact force with respect to the solid lubricant 16b and the photosensitive drum 11 is insufficient. Therefore, it is preferable that the length of the bristle is in the above range.

The brush-like rotating member 16a rotates so as to come into contact with the photosensitive drum 11 that rotates clockwise in FIGS. 2 and 3 in the counter direction (clockwise rotation in FIGS. 2 and 3). Further, the brush-like rotating member 16a (brush hair) is disposed so as to be in sliding contact with the solid lubricant 16b and the photosensitive drum 11, and the lubricant is changed from the solid lubricant 16b by the rotation of the brush-like rotating member 16a. After the scraped lubricant is conveyed to the sliding contact position with the photosensitive drum 11, the lubricant is applied onto the photosensitive drum 11.
A compression spring 16c (biasing member) is disposed behind the solid lubricant 16b in order to eliminate contact unevenness between the brush-like rotating member 16a and the solid lubricant 16b. The member 16a is biased. The solid lubricant 16a is accommodated and held in the cover member 16f together with the compression spring 16c.

In the present embodiment, the solid lubricant 16b is mainly formed of zinc stearate. Specifically, the solid lubricant 16b is preferably prepared by dissolving a lubricating oil additive mainly composed of zinc stearate, having no side effects due to overcoating, and having sufficient lubricity.
Zinc stearate is a typical lamellar crystal powder. A lamellar crystal has a layered structure in which amphiphilic molecules are self-organized, and when a shearing force is applied, the crystal breaks along the layers and is slippery. Therefore, the surface of the photosensitive drum 11 can be made to have low friction. In other words, the surface of the photosensitive drum 11 can be effectively covered with a small amount of lubricant by the lamellar crystals that receive the shearing force and uniformly cover the surface of the photosensitive drum 11.

  As the solid lubricant 16b, in addition to zinc stearate, stearic acid groups such as barium stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate, calcium stearate, etc. The thing which has can be used. In addition, the same fatty acid group zinc oleate, barium oleate, lead oleate, the same compound as stearic acid, zinc palmitate, barium palmitate, lead palmitate, the following compound similar to stearic acid May be used. In addition, caprylic acid, linolenic acid, corinolenic acid and the like can be used as the fatty acid group. In addition, waxes such as candelilla wax, canrunauba wax, rice wax, wax, coconut oil, beeswax, and lanolin can also be used. These easily become organic solid lubricants and have good compatibility with the toner.

When the solid lubricant 16b is applied to the surface of the photosensitive drum 11 via the brush-like rotating member 16a, a powdery lubricant is applied to the surface of the photosensitive drum 11, but the lubricity is sufficient in this state. Therefore, the blade-like member 16d (thinned blade) functions as a member for uniformizing the lubricant. The blade-like member 16d forms a film of the lubricant on the photosensitive drum 11, and the lubricant exhibits its lubricity sufficiently.
At this time, the finer the powdery lubricant applied by the brush-like rotating member 16a, the thinner the thin film on the photosensitive drum 11 at the molecular film level by the blade-like member 16d.

Hereinafter, the configuration and operation of the lubricant supply device 16 which are characteristic in the present embodiment will be described in detail.
With reference to FIGS. 2 and 3, the lubricant supply device 16 in the present embodiment is provided with a cover member 16 f (see FIGS. 4, 5, etc.) covering a part thereof. The cover member 16f is detachably installed with respect to the lubricant supply device 16 (process cartridges 10Y, 10M, 10C, 10BK) so that a part of the solid lubricant 16b enters into the cover member 16f via the compression spring 16c. ing.

Specifically, the cover member 16f is easily attached and detached by screw fastening / unfastening to the casing of the lubricant supply device 16 below the lubricant supply device 16 (process cartridges 10Y, 10M, 10C, 10BK). It is configured to be able to. One end of the compression spring 16c is held by the base surface 16f1 (see FIG. 4 and the like) of the cover member 16f in a state where the lubricant supply device 16 is mounted, and the solid lubricant 16b is absorbed by the urging force of the compression spring 16c. It is biased toward the brush-like rotating member 16a. On the other hand, by unscrewing a screw (not shown) and taking out the cover member 16f from the lubricant supply device 16, the solid lubricant 16b (consumed) is used together with the compression spring 16c. After taking out, a new solid lubricant 16b is newly mounted, and replacement maintenance work for the solid lubricant 16b is performed.
As described above, by detachably installing the cover member 16f with respect to the lubricant supply device 16, the workability of the replacement maintenance of the solid lubricant 16b becomes very easy. Furthermore, since the cover member 16f is formed of a highly rigid metal material (sheet metal), the reaction force of the compression spring 16c (the reaction force of the force that urges the solid lubricant 16b toward the brush-like rotation member 16a). It will not be deformed against).

4 to 6, the cover member 16 f is formed of four side surfaces 16 f 2 to 16 f 3 (thirds) with the four sides of the base surface 16 f 1 being bent from each other by box bending a sheet metal such as stainless steel. The fourth side surface facing the side surface 16f3 is not shown.) Is configured to stand upright.
The cover member 16f has two corners 16f21 and 16f31 formed on the side of at least one of the two side surfaces 16f2 and 16f3 that are adjacent to each other among the four side surfaces 16f2 and 16f3 from the outside. A fitting member 16f6 that fits so as to cover is provided.

Specifically, as shown in FIG. 6, the cover member 16f in a state where the fitting member 16f6 is not installed is formed so that the base surface 16f1 is a bottom surface and the side surfaces are erected in four directions to form a substantially box shape. Has been. The first side surface 16f2 extending in the longitudinal direction (the direction perpendicular to the paper surface in FIGS. 2 and 3) is bent so that the angle formed with the base surface 16f1 is an obtuse angle. A corner portion 16f21 is formed at the end portion (a bending source position) with the base surface 16f1. The second side surface 16f3 facing the first side surface 16f2 is bent so that the angle formed with the base surface 16f1 is substantially a right angle, and the boundary (bending origin) with the base surface 16f1 at the longitudinal end portion thereof. The corner portion 16f31 is formed at the position. The third side surface 16f4 extending in the short direction so as to be adjacent to the first side surface 16f2 and the second side surface 16f3 is bent so that the angle formed with the base surface 16f1 is substantially a right angle, A gap is provided between the both end portions and the first side surface 16f2 and the second side surface 16f3, and a positioning hole portion 16f41 (through hole) is provided in the center portion.
Note that the cover member 16f formed by bending the sheet metal in this way has sharp edges and burrs formed at the corners 16f21 and 16f31, and as such, There is a high possibility that the operator will be injured or that the image forming apparatus main body 1 and the lubricant supply device 16 will be damaged during the mounting operation of the cover member 16f.

Here, as shown in FIGS. 4 and 5, fitting members 16f6 are respectively installed at both ends in the longitudinal direction of the cover member 16f formed in a substantially box shape (illustration of one end is omitted). Yes.)
Specifically, the fitting member 16f6 includes a recess 16f61 that fits between both ends of the third side surface 16f4 from the inside of the third side surface 16f4 (at least one side surface), and the first side surface from the corner portions 16f21 and 16f31. An outer edge portion 16f62 formed in a range exceeding the width of the third side surface 16f4 is provided so as to cover the edge portions 16f22 and 16f32 in the 16f2 and the second side surface 16f3 from the outside. That is, the fitting member 16f6 is installed so as to be in close contact with and engaged with the third side surface 16f4 from the inside, and both end portions (outer edge portions 16f62) thereof are corner portions 16f21 and 16f21 on the first side surface 16f2 and the second side surface 16f3. 16f31 and a part of edge part 16f22, 16f32 are covered, and it installs so that it may be pinched | interposed between the inner surface of the 3rd side surface 16f4, and edge part 16f22, 16f32.

  With such a configuration, the cover member 16f can be obtained by hand without performing expensive secondary processing such as cutting, polishing, and welding in order to remove sharp edges and burrs formed in the corner portions 16f21 and 16f31. It is possible to surely prevent a malfunction or the like that a user or an operator touches an edge or a burr and is injured. Furthermore, since the fitting member 16f6 covers and protects the two corners 16f21 and 16f31 simultaneously with one component, the number of components of the cover member 16f can be relatively reduced. Particularly, in the cover member 16f in the present embodiment, the standing angles of the four side surfaces that stand up with respect to the base surface 16f1 are not constant, and the protection members are installed so as to individually cover the four corner portions. However, since these protective members cannot be made into a common part, the fitting member 16f6 that covers and protects the two corners 16f21 and 16f31 simultaneously with one part is useful from the viewpoint of reducing the number of parts. In addition, the fitting member 16f6 is installed on the cover member 16f so that the fitting member 16f6 is engaged with the cover member 16f according to the shape of the cover member 16f without using screws or adhesives. In addition, the workability can be improved even when the removal work is performed during recycling or the like.

  In the present embodiment, the fitting member 16f6 is a substantially plate-like member formed of a polymer compound (plastic material). Therefore, the inner volume of the cover member 16f is not greatly reduced, and the workability of the fitting member 16f6 can be improved and the manufacturing cost can be reduced. Furthermore, since it becomes easy to elastically deform the fitting member 16f6, installation to the cover member 16f is facilitated while the fitting member 16f6 is elastically deformed.

Here, in the present embodiment, referring to FIGS. 4 and 5, etc., the boss portion 16f61a that fits into the positioning hole portion 16f41 formed in the third side surface 16f4 is formed in the recess portion 16f61 of the fitting member 16f6. Is formed. That is, the fitting member 16f6 is installed so as to be sandwiched between the inner side surface of the third side surface 16f4 and the edge portions 16f22 and 16f32 in a state where the boss portion 16f61a is fitted in the positioning hole portion 16f41. Become.
With such a configuration, since the position of the fitting member 16f6 in the cover member 16f is surely determined, the fitting member 16f6 falls off the position of the cover member 16f or is displaced so as to cover the corner portions 16f21 and 16f31. The problem that no longer works is suppressed.

Referring to FIG. 7, in fitting member 16f6 in the present embodiment, the portion where boss portion 16f61a is formed can be supported in a cantilever manner in fitting member 16f6.
Specifically, as shown in FIG. 7, in the recess 16f61 of the fitting member 16f6, a notch is formed around the boss portion 16f61a, so that the cantilever support portion 16f61b (one side outer edge portion 16f62) on which the boss portion 16f61a is installed. The side is fixed.) Is provided.
With this configuration, as shown in FIG. 8, when the fitting member 16f6 is attached to the cover member 16f, the boss portion 16f61a is positioned in the positioning hole while elastically deforming the cantilever support portion 16f61b in the direction of the arrow. Since it can be made to fit in part 16f41, the mounting property (or detachability) of fitting member 16f6 to cover member 16f improves.

Here, as described above with reference to FIG. 1, in the image forming apparatus 1 according to the present embodiment, the monochrome process cartridge 10BK as the black image forming unit is used for the color as the other image forming unit. The process cartridges 10Y, 10M, and 10C are disposed on the most downstream side with respect to the traveling direction of the intermediate transfer belt 17. Further, the monochrome process cartridge 10BK (black image forming unit) is different from the color process cartridges 10Y, 10M, and 10C (other image forming units) in the lubricant held in the lubricant supply device 16. The capacity is increased.
Specifically, referring to FIGS. 2 and 3, the size of the solid lubricant 16b of the lubricant supply device 16 in the monochrome process cartridge 10BK (black image forming unit) is equal to the color process cartridge 10Y. It is configured to be larger than the size of the solid lubricant 16b of the lubricant supply device 16 in 10M and 10C (other image forming units).

As described above, the solid lubricant 16b of the monochrome process cartridge 10BK is configured to be large, so that the total time for supplying the lubricant to the photosensitive drum 11 is reduced as compared with the color process cartridges 10Y, 10M, and 10C. Since it can be taken longer, the time when the photosensitive drum 11 deteriorates can be delayed. Therefore, it is possible to extend the life of the monochrome process cartridge 10BK, which is used more frequently than the color process cartridges 10Y, 10M, and 10C.
On the other hand, by making the solid lubricant 16b larger as described above, the vertical height H1 of the monochrome process cartridge 10BK is set to the vertical height H2 of the color process cartridges 10Y, 10M, and 10C. In comparison, it becomes larger (H1> H2). Specifically, in the monochrome process cartridge 10BK, the lubricant supply device 16 protrudes downward as much as the solid lubricant 16b is increased.

However, in the image forming apparatus 1 according to the present embodiment, among the plurality of process cartridges 10Y, 10M, 10C, and 10BK, the monochrome process cartridge 10BK is disposed at the endmost position (most downstream side). Has been. Thereby, a collective space can be secured at positions below the plurality of process cartridges 10Y, 10M, 10C, and 10BK. Specifically, in the present embodiment, referring to FIG. 1, a plurality of process cartridges 10 </ b> Y, 10 </ b> M, 10 </ b> C, and the writing unit 6 do not interfere with the lubricant supply device 16 of the monochrome process cartridge 10 </ b> BK. It is located near 10BK.
With such a configuration, even when the lubricant supply device 16 (solid lubricant 16b) is increased in size and the life of the monochrome process cartridge 10BK is extended, the height in the vertical direction of the image forming apparatus 1 is increased. It is not necessary to increase the size.
The cover member 16f is formed in accordance with the shape of the lubricant supply device 16 of the monochrome process cartridge 10BK and the shape of the lubricant supply device 16 of the color process cartridges 10Y, 10M, and 10C.

2 and 3, in the present embodiment, the monochrome process cartridge 10BK (black image forming unit) is a color process cartridge 10Y, 10M, 10C (other image forming units). The outer diameter of the brush-like rotating member 16a is configured to be larger than that. Specifically, the brush-like rotating member 16a of the monochrome process cartridge 10BK and the brush-like rotating member 16a of the color process cartridges 10Y, 10M, and 10C each have a brush hair length of 0.2 to 20 mm. And it is comprised so that the outer diameter of the metal core in which the bristle was wound may differ.
By configuring the brush-like rotating member 16a (core metal) to have an increased outer diameter in this way, deformation of the brush-like rotating member 16a occurs and uneven application of the lubricant applied on the photosensitive drum 11 ( (Deviation) is less likely to occur.
By configuring the brush-like rotating member 16a to have a larger outer diameter, the vertical height H1 of the monochrome process cartridge 10BK is higher than the vertical height of the color process cartridges 10Y, 10M, and 10C. It becomes larger than H2 (H1> H2). However, in the image forming apparatus 1 according to the present embodiment, among the plurality of process cartridges 10Y, 10M, 10C, and 10BK, the monochrome process cartridge 10BK is disposed at the endmost position (most downstream side). Therefore, it is not necessary to increase the height of the entire image forming apparatus 1 in the vertical direction.

2 and 3, in the present embodiment, the monochrome process cartridge 10BK (black image forming unit) is a color process cartridge 10Y, 10M, 10C (other image forming units). Compared to the angle of contact between the blade-shaped member 16d and the contact angle of the blade-shaped member 16d (the line connecting the center of the photosensitive drum 11 and the position of contact with the blade-shaped member 16d). ) Is large.
Specifically, the contact angle θ2 of the blade-like member 16d of the color process cartridges 10Y, 10M, and 10C is set to about 90 degrees, whereas the blade-like member 16d of the monochrome process cartridge 10BK is set. The contact angle θ1 is set within a range of 91 to 160 degrees.
As described above, in the monochrome process cartridge 10BK, the contact angle θ1 of the blade-shaped member 16d is set to be an obtuse angle, so that the frictional resistance of the blade-shaped member 16d against the photosensitive drum 11 is reduced. Therefore, the wear deterioration of both the members 11 and 16d due to the sliding contact between the blade-like member 16d and the photosensitive drum 11 is delayed, and the driving torque of the photosensitive drum 11 is reduced.
By setting the contact angle of the blade-like member 16d to an obtuse angle, the vertical height of the monochrome process cartridge 10BK is set to the vertical height of the color process cartridges 10Y, 10M, and 10C. Compared to the larger. However, in the image forming apparatus 1 according to the present embodiment, among the plurality of process cartridges 10Y, 10M, 10C, and 10BK, the monochrome process cartridge 10BK is disposed at the endmost position (most downstream side). Therefore, it is not necessary to increase the height of the entire image forming apparatus 1 in the vertical direction.

Here, in the present embodiment, the solid lubricant 16b in the monochrome process cartridge 10BK (black image forming unit) and the solid lubricant in the color process cartridges 10Y, 10M, and 10C (other image forming units). Different types can be used as 16b. Specifically, as the solid lubricant 16b in the color process cartridges 10Y, 10M, and 10C, a solid lubricant 16b in the monochrome process cartridge 10BK (black image forming unit) is used. What was formed by mixing at least boron nitride with zinc stearate can be used.
By using the solid lubricant 16b made of zinc stearate, sufficient lubricity of the surface of the photosensitive drum 11 can be obtained as described above. Further, by using the solid lubricant 16b made of zinc stearate mixed with boron nitride, further sufficient lubricity of the surface of the photosensitive drum 11 can be obtained. Accordingly, the life of the photosensitive drum 11 of the monochrome process cartridge 10BK can be further extended.

2 and 3, in the present embodiment, the monochrome process cartridge 10BK (black image forming unit) is a color process cartridge 10Y, 10M, 10C (other image forming units). The gap between the charging roller 12a and the photosensitive drum 11 is formed so as to be smaller than that.
Specifically, the gap δ1 between the charging roller 12a and the photosensitive drum 11 in the monochrome process cartridge 10BK is larger than the gap δ2 between the charging roller 12a and the photosensitive drum 11 in the color process cartridges 10Y, 10M, and 10C. Is set to be small.
In this way, in the monochrome process cartridge 10BK, the gap δ1 between the charging roller 12a and the photosensitive drum 11 is set to be relatively small, so the amount of ozone generated when the charging roller 12a is discharged is reduced. Can be reduced. Furthermore, the vertical height of the monochrome process cartridge 10BK can be reduced by setting the gap δ1 between the charging roller 12a and the photosensitive drum 11 to be small.

  As described above, according to the present embodiment, since the fitting member 16f6 that fits the two corner portions 16f21 and 16f31 from the outside is installed on the cover member 16f, the number of parts is relatively small. At least, the plurality of corner portions 16f21 and 16f31 can be covered and protected.

In this embodiment, the process cartridges 10Y, 10M, and the process cartridges 10Y, 10M, and the like in the image forming unit (the photosensitive drum 11, the charging unit 12, the developing unit 13, the cleaning unit 15, and the lubricant supply device 16) are integrated. 10C and 10BK are configured to reduce the size of the image forming unit and improve maintenance workability.
In contrast, each of the image forming units 11, 12, 13, 15, and 16 can be configured to be installed in the apparatus main body 1 in a replaceable manner without being a component of the process cartridge. Even in such a case, the same effect as the present embodiment can be obtained.
In the present embodiment, the present invention is applied to the image forming apparatus equipped with the two-component developing type developing unit 13 using the two-component developer. However, the one-component developing type using the one-component developer is used. Of course, the present invention can also be applied to an image forming apparatus in which the developing unit 13 is mounted.

  Further, in the present embodiment, the monochrome process cartridge 10BK (black image forming unit) has an intermediate transfer belt compared to the color process cartridges 10Y, 10M, and 10C (other color image forming units). It was comprised so that it might be arrange | positioned most downstream with respect to the 17 running directions. On the other hand, the monochrome process cartridge 10BK is configured to be disposed on the most upstream side in the traveling direction of the intermediate transfer belt 17 as compared with the color process cartridges 10Y, 10M, and 10C. You can also. Even in such a case, the same effect as in the present embodiment can be obtained.

In the present embodiment, the present invention is applied to the lubricant supply device 16 that supplies the lubricant onto the photosensitive drum 11 as the image carrier. However, the image carrier other than the photosensitive drum 11 is lubricated. Naturally, the present invention can also be applied to a lubricant supply device that supplies a lubricant (for example, a lubricant supply device that supplies a lubricant to the intermediate transfer belt 17).
In the present embodiment, the solid lubricant 16b is partially inserted into the cover member 16f via the compression spring 16c. However, the solid lubricant is inserted into the cover member 16f via the compression spring 16c. It is also possible to configure so that all of 16b enters.
Even in these cases, the same effect as in the present embodiment can be obtained by providing the cover member 16f with the fitting member 16f6 as in the present embodiment.

  In the present embodiment, the present invention is applied to the cover member 16f installed in the lubricant supply device 16 in the image forming apparatus 1. However, the cover member 16f is installed in a place other than the lubricant supply apparatus 16 or other than the image forming apparatus 1. Naturally, the present invention can also be applied to the cover member. Even in such a case, the same effect as in the present embodiment can be obtained by providing the cover member 16f with the fitting member 16f6 as in the present embodiment.

  It should be noted that the present invention is not limited to the present embodiment, and it is obvious that the present embodiment can be modified as appropriate within the scope of the technical idea of the present invention, other than suggested in the present embodiment. is there. In addition, the number, position, shape, and the like of the constituent members are not limited to the present embodiment, and the number, position, shape, and the like suitable for implementing the present invention can be achieved.

1 image forming apparatus body (apparatus body),
11 Photosensitive drum (image carrier),
16 Lubricant supply device (lubricant supply unit),
16a brush-like rotating member,
16b solid lubricant,
16c compression spring (biasing member),
16e holder,
16f cover member,
16f1 base surface,
16f2 first side surface, 16f3 second side surface, 16f4 third side surface,
16f6 fitting member,
16f21, 16f31 corner,
16f22, 16f32 edge part,
16f41 positioning hole,
16f61 recess,
16f61a boss part, 16f61b cantilever support part,
16f62 outer edge.

JP 2003-86960 A Japanese Patent No. 4299194 JP 2007-86321 A JP 2000-172119 A

Claims (8)

A cover member in which four side surfaces of the base surface are raised by bending the sheet metal in a box, and the four side surfaces are raised;
The fitting member which fits so that two corners formed on the side of at least one of the two side surfaces adjacent to each other in the two side surfaces opposed to each other among the four side surfaces may be installed. A characteristic cover member.   The fitting member covers from the outside from the inside of the at least one side surface to the recessed portion that fits the both end portions of the side surface and the edge portions of the two opposite side surfaces from the corner portion. The cover member according to claim 1, further comprising an outer edge portion formed in a range exceeding a width of the one side surface.   The cover member according to claim 2, wherein the concave portion of the fitting member is formed with a boss portion that fits into a positioning hole portion formed on the at least one side surface.   The cover member according to claim 3, wherein the fitting member is formed so that a portion where the boss portion is formed is cantilevered by the fitting member.   The cover member according to any one of claims 1 to 4, wherein the fitting member is a plate-like member formed of a polymer compound. A lubricant supply device for supplying a lubricant onto an image carrier on which a toner image is carried,
The cover member according to any one of claims 1 to 5,
A brush-like rotating member that rotates in a predetermined direction and is provided with brush bristles that slidably contact the image carrier;
A solid lubricant slidingly contacting the brush bristles of the brush-like rotating member;
A biasing member that biases the solid lubricant toward the brush-like rotating member;
With
The lubricant supply device according to claim 1, wherein the cover member is detachably attached to the device so that a part or all of the solid lubricant enters inside the cover member via the biasing member. A process cartridge that is detachably attached to the image forming apparatus main body,
A process cartridge comprising the lubricant supply device according to claim 6 and the image carrier.   An image forming apparatus comprising the lubricant supply device according to claim 6 and the image carrier.

Images