JP2009276482A - Lubricant supplying device, cleaning device, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricant supplying device capable of stably supplying lubricant on an image carrier without adhesion of deposit removed from a brush-like rotating member by a removal member on solid lubricant, and to provide a cleaning device, a process cartridge, and an image forming apparatus. <P>SOLUTION: The lubricant supplying device includes: the brush-like rotating member 25b around which brush bristles brought into slide contact with the image carrier 21 and the solid lubricant 45 are provided; and the removal member 47 removing the deposit adhering on the brush-like rotating member 25b. A collecting member 48 collecting the deposit removed from the brush-like rotating member 25b by a removal member 47 is provided at the downstream side in the rotating direction of the brush-like rotating member 25b relative to the removal member 47 and at the upstream side in the rotating direction of the brush-like rotating member 25b relative to the solid lubricant 45. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lubricant supply device (lubricant application device) for supplying a lubricant onto an image carrier such as a photoconductor drum, a photoconductor belt, and an intermediate transfer belt, and a cleaning device, process cartridge, and The present invention relates to an image forming apparatus.

  Conventionally, in an image forming apparatus using an electrophotographic method such as a copying machine, a printer, a facsimile, or a composite machine thereof, the deposits such as untransferred toner adhered on an image carrier such as a photosensitive drum are cleaned. A technique is known that uses a lubricant supply device that supplies a lubricant onto the image carrier in order to reliably clean the device and reduce wear of the image carrier and the cleaning blade (for example, Patent Documents). 1 etc.).

  Specifically, the untransferred toner remaining on the image carrier after the transfer process should be completely removed by a cleaning blade (cleaning device) that contacts the image carrier. However, when the cleaning blade deteriorates with time due to contact with the image carrier (abrasion), cleaning failure may occur due to slipping through the gap between the cleaning blade where the untransferred toner is worn and the image carrier. Even when the cleaning blade is not deteriorated, when small toner or spherical toner is used, the toner enters a slight gap between the cleaning blade and the image carrier and eventually passes through the gap. A cleaning failure sometimes occurred. Furthermore, if toner or an external additive or paper dust contained in the toner slips through the gap between the cleaning blade and the image carrier, it adheres to the image carrier and forms a film. There was also.

  In response to such a problem, by applying a lubricant on the image carrier, the friction coefficient on the image carrier is reduced, so that deterioration of the cleaning blade and the image carrier is reduced. Since the removability of deposits such as untransferred toner adhering to the toner is improved, it is possible to suppress the occurrence of poor cleaning and filming over time.

Specifically, the lubricant supply device removes a brush-like rotating member (brush roller) that is slidably in contact with the image carrier, a solid lubricant that is in contact with the brush-like rotating member, and a toner (attachment) attached to the brush-like rotating member. It is comprised with the removal member (flicker) etc. which do. Here, the lubricant supply device is provided in the cleaning device, and the cleaning blade is in contact with the image carrier (photoconductor) on the downstream side of the brush-like rotating member.
Then, the lubricant is gradually scraped off from the solid lubricant by the brush-like rotating member rotating in a predetermined direction, and the lubricant scraped off by the brush-like rotating member is applied (supplied) to the surface of the image carrier. Further, deposits such as untransferred toner remaining on the image carrier are removed by a cleaning blade disposed on the downstream side of the brush-like rotating member. At this time, deposits such as untransferred toner remaining on the image carrier are also removed by the brush-like rotating member, and the deposits removed by the brush-like rotating member are removed from the brush-like rotating member by the removing member. .

  On the other hand, Patent Document 1 discloses a technique in which two flickers are brought into contact with a brush-like rotating member for the purpose of efficiently removing deposits attached to the brush-like rotating member.

JP 2007-212979 A

In the conventional technique described above, the toner (adhered matter) removed from the brush-like rotating member by the removing member adheres to the solid lubricant and enters between the solid lubricant and the brush-like rotating member, resulting in a brush-like shape. The amount of lubricant scraped off from the solid lubricant by the rotating member may be reduced. In such a case, the amount of lubricant supplied from the brush-like rotating member onto the image carrier is also reduced, and the function as the lubricant supply device is reduced.
Such a problem is not particularly negligible when the distance between the removal member (flicker) and the solid lubricant is relatively short (for example, the configuration shown in FIG. 1 of Patent Document 1). become.

  The present invention has been made in order to solve the above-described problems. The deposits removed from the brush-like rotating member by the removing member do not adhere to the solid lubricant, and the lubricant on the image carrier. It is an object of the present invention to provide a lubricant supply device, a cleaning device, a process cartridge, and an image forming apparatus that can stably supply the toner.

  According to a first aspect of the present invention, there is provided a lubricant supply device for supplying a lubricant onto an image carrier, wherein the bristle in sliding contact with the image carrier and the solid lubricant is provided. A brush-shaped rotating member provided around the brush-shaped rotating member; and a removing member that removes deposits attached to the brush-shaped rotating member. A recovery member for recovering the deposits removed from the brush-like rotating member by the removing member is disposed upstream of the solid lubricant in the rotational direction of the brush-like rotating member.

  According to a second aspect of the present invention, there is provided the lubricant supply device according to the first aspect, wherein the recovery member is a roller-like rotating member in which an intermediate resistance elastic layer is formed on a cored bar. Then, the deposit is electrically adsorbed by applying a predetermined voltage to the cored bar.

  According to a third aspect of the present invention, there is provided the lubricant supply device according to the second aspect, wherein the scraper for separating the adhering matter adsorbed on the roller-like rotating member from the roller-like rotating member is the roller-like member. This is in contact with the rotating member.

  According to a fourth aspect of the present invention, in the lubricant supply device according to the second or third aspect, the roller-like rotating member rotates in the same direction as the brush-like rotating member. To do.

  The lubricant supply device according to claim 5 is the invention according to any one of claims 1 to 4, wherein the recovery member faces the brush-like rotating member in a non-contact manner. It is arranged to do.

  According to a sixth aspect of the present invention, in the lubricant supply device according to the first to fifth aspects, the brush bristles of the brush-like rotating member have the same polarity as the polarity of the toner. It is formed of a high-resistance resin fiber that is frictionally charged.

  A lubricant supply device according to a seventh aspect of the invention is the invention according to any one of the first to sixth aspects, wherein the removal member is in sliding contact with the brush bristles of the brush-like rotation member. It is a plate-shaped member.

  A lubricant supply device according to an eighth aspect of the present invention is the lubricant supply device according to any one of the first to seventh aspects, wherein the solid lubricant is zinc stearate.

  According to a ninth aspect of the present invention, in the lubricant supply device according to the first aspect, the image carrier has a crosslinked structure and a charge transport material is dispersed. A protective layer formed of a binder resin is provided on the surface.

  According to a tenth aspect of the present invention, a cleaning device includes the lubricant supply device according to any one of the first to ninth aspects, wherein the image carrier is mounted on the lubricant supply device. A cleaning blade for cleaning the image bearing member is disposed on the downstream side in the traveling direction.

  A process cartridge according to an eleventh aspect of the present invention is a process cartridge which is detachably installed on the main body of the image forming apparatus, and is according to any one of the first to ninth aspects. The lubricant supply device and the image carrier are integrated.

  An image forming apparatus according to a twelfth aspect of the present invention includes the lubricant supply device according to any one of the first to ninth aspects and the image carrier.

  In the present application, “process cartridge” means a charging device (charging unit) for charging an image carrier, a developing device (developing unit) for developing a latent image formed on the image carrier, and an image carrier. It is defined as a unit in which at least one of the cleaning devices (cleaning units) for cleaning the top and the image carrier are integrated and detachably installed on the image forming apparatus main body.

  In the present invention, a collecting member for collecting the deposit removed from the brush-like rotating member by the removing member is disposed between the removing member and the solid lubricant. Accordingly, the lubricant removed from the brush-like rotating member by the removing member does not adhere to the solid lubricant, and the lubricant is stably supplied onto the image carrier. A process cartridge and an image forming apparatus can be provided.

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.
In FIG. 1, 1 is an apparatus main body of a color copying machine as an image forming apparatus, 2 is a writing section (exposure section) that emits laser light based on input image information, and 20Y, 20M, 20C, and 20BK are colors (yellow, magenta). , Cyan, and black), 21 is a photosensitive drum as an image carrier accommodated in each of the process cartridges 20Y, 20M, 20C, and 20BK, 22 is a charging unit that charges the photosensitive drum 21, Reference numerals 23Y, 23M, 23C, and 23BK denote developing devices (developing units) that develop the electrostatic latent image formed on the photosensitive drum 21, and 24 denotes a toner image formed on the photosensitive drum 21 to the intermediate transfer belt 27. A transfer bias roller 25 for transferring, a cleaning device (cleaning unit) for collecting untransferred toner on the photosensitive drum 21, Show.

  In addition, 27 is an intermediate transfer belt on which toner images of a plurality of colors are transferred in an overlapping manner, 28 is a second transfer bias roller for transferring the toner image formed on the intermediate transfer belt 27 to the recording medium P, and 29 is an intermediate transfer belt. 27 is an intermediate transfer belt cleaning unit that collects untransferred toner, 30 is a conveyance belt that conveys a recording medium P on which a four-color toner image is transferred, and 32Y, 32M, 32C, and 32BK are developing devices 23Y and 23M. , 23C and 23BK, a toner replenishing unit for replenishing toner of each color, 51 a document conveying unit for conveying the document D to the document reading unit 55, 55 for a document reading unit for reading image information of the document D, 61 for transfer paper, etc. A paper feed unit for storing the recording medium P, and a fixing unit 66 for fixing an unfixed image on the recording medium P are shown.

Here, each of the process cartridges 20Y, 20M, 20C, and 20BK is a unit in which the photosensitive drum 21, the charging unit 22, and the cleaning device 25 (with a lubricant supply device installed therein) are integrated. is there. The process cartridges 20Y, 20M, 20C, and 20BK are exchanged with respect to the apparatus main body 1 in a predetermined exchange cycle. Similarly, the developing devices 23Y, 23M, 23C, and 23BK are also exchanged with respect to the apparatus main body 1 in a predetermined exchange cycle.
Image formation of each color (yellow, magenta, cyan, black) is performed on the photosensitive drum 21 in each of the process cartridges 20Y, 20M, 20C, and 20BK.

Hereinafter, an operation during normal color image formation in the image forming apparatus will be described.
First, the document D is transported from the document table in the direction of the arrow in the drawing by the transport roller of the document transport unit 51 and placed on the contact glass 53 of the document reading unit 55. Then, the document reading unit 55 optically reads the image information of the document D placed on the contact glass 53.

  Specifically, the document reading unit 55 scans the image of the document D on the contact glass 53 while irradiating light emitted from the illumination lamp. Then, the light reflected by the document D is imaged on the color sensor via the mirror group and the lens. The color image information of the document D is read for each RGB (red, green, blue) color separation light 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, the image information of each color of yellow, magenta, cyan, and black is transmitted to the writing unit 2. Then, laser light (exposure light) based on the image information of each color is emitted from the writing unit 2 toward the photosensitive drums 21 of the corresponding process cartridges 20Y, 20M, 20C, and 20BK.

On the other hand, the four photosensitive drums 21 rotate in the clockwise direction in FIG. First, the surface of the photosensitive drum 21 is uniformly charged at a position facing the charging unit 22 (a charging process). Thus, a charged potential is formed on the photosensitive drum 21. Thereafter, the surface of the charged photosensitive drum 21 reaches the irradiation position of each laser beam.
In the writing unit 2, laser light corresponding to the image signal is emitted from the light source corresponding to each color. The laser light is incident on the polygon mirror 3 and reflected, and then passes through the lenses 4 and 5. The laser light after passing through the lenses 4 and 5 passes through different optical paths for each of the yellow, magenta, cyan, and black color components (this is an exposure process).

  The laser beam corresponding to the yellow component is reflected by the mirrors 6 to 8 and then irradiated onto the surface of the photosensitive drum 21 of the first process cartridge 20Y from the left side of the drawing. At this time, the yellow component laser light is scanned in the rotation axis direction (main scanning direction) of the photosensitive drum 21 by the polygon mirror 3 that rotates at high speed. Thus, an electrostatic latent image corresponding to the yellow component is formed on the photosensitive drum 21 charged by the charging unit 22.

  Similarly, the laser beam corresponding to the magenta component is reflected by the mirrors 9 to 11 and then irradiated to the surface of the photosensitive drum 21 of the second process cartridge 20M from the left side of the paper, thereby causing an electrostatic latent image corresponding to the magenta component. An image is formed. The cyan component laser light is reflected by the mirrors 12 to 14 and then irradiated onto the surface of the photosensitive drum 212 of the third process cartridge 20C from the left side of the drawing to form a cyan component electrostatic latent image. The black component laser light is reflected by the mirror 15 and then irradiated on the surface of the photosensitive drum 21 of the fourth process cartridge 20BK from the left side of the paper, thereby forming an electrostatic latent image of black component.

Thereafter, the surface of the photosensitive drum 21 on which the electrostatic latent images of the respective colors are formed reaches positions facing the developing devices 23Y, 23M, 23C, and 23BK, respectively. Then, the respective color toners are supplied from the developing devices 23Y, 23M, 23C, and 23BK onto the photosensitive drum 21, and the latent image on the photosensitive drum 21 is developed (this is a developing step).
Thereafter, the surface of the photosensitive drum 21 after the development process reaches the position facing the intermediate transfer belt 27 after passing the position facing the photosensor 41 (see FIG. 2). Here, the transfer bias roller 24 is installed at each facing position so as to contact the inner peripheral surface of the intermediate transfer belt 27. Then, at the position of the transfer bias roller 24, the images of the respective colors formed on the photosensitive drum 21 are sequentially superimposed and transferred onto the intermediate transfer belt 27 (first transfer step).

Then, the surface of the photosensitive drum 21 after the first transfer process reaches a position facing the cleaning device 25. Then, the untransferred toner remaining on the photosensitive drum 21 is collected by the cleaning device 25 (this is a cleaning process).
Thereafter, the surface of the photosensitive drum 21 passes through a static elimination unit (not shown), and a series of image forming processes on the photosensitive drum 21 is completed.

On the other hand, the surface of the intermediate transfer belt 27 on which the images of the respective colors on the photosensitive drum 21 are transferred in an overlapping manner travels in the direction of the arrow in the drawing and reaches the position of the second transfer bias roller 28. Then, the full-color image on the intermediate transfer belt 27 is secondarily transferred onto the recording medium P at the position of the second transfer bias roller 28 (second transfer step).
Thereafter, the surface of the intermediate transfer belt 27 reaches the position of the intermediate transfer belt cleaning unit 29. Then, the untransferred toner on the intermediate transfer belt 27 is collected by the intermediate transfer belt cleaning unit 29, and a series of transfer processes on the intermediate transfer belt 27 is completed.

Here, the recording medium P at the position of the second transfer bias roller 28 is transported from the paper feeding unit 61 via the transport guide 63, the registration roller 64, and the like.
Specifically, the recording medium P fed by the paper feeding roller 62 from the paper feeding unit 61 that stores the recording medium P passes through the conveyance guide 63 and is guided to the registration roller 64. The recording medium P that has reached the registration roller 64 is conveyed toward the position of the second transfer bias roller 28 in synchronization with the toner image on the intermediate transfer belt 27.

Thereafter, the recording medium P on which the full-color image is transferred is guided to the fixing unit 66 by the conveyance belt 30. In the fixing unit 66, the color image is fixed on the recording medium P at the nip between the heating roller 67 and the pressure roller 68.
Then, the recording medium P after the fixing process is discharged as an output image by the paper discharge roller 69 to the outside of the apparatus main body 1, and a series of image forming processes is completed.

Next, the image forming unit of the image forming apparatus will be described in detail with reference to FIG.
FIG. 2 is a cross-sectional view showing the image forming unit. The four image forming units installed in the apparatus main body 1 have substantially the same structure except that the color of the toner T used in the image forming process is different. Therefore, the alphabet of reference numerals in the process cartridge, the developing device, and the toner replenishing unit. (Y, M, C, BK) is omitted for illustration.
As shown in FIG. 2, the process cartridge 20 mainly contains a photosensitive drum 21 as an image carrier, a charging unit 22, and a cleaning device 25 integrally in a case 26.

Here, the photosensitive drum 21 as an image bearing member is a negatively charged organic photosensitive member, in which a photosensitive layer or the like is provided on a drum-shaped conductive support.
Although not shown, the photosensitive drum 21 has a conductive support as a base layer, an undercoat layer as an insulating layer, a charge generation layer and a charge transport layer as a photosensitive layer, and a protective layer (surface layer) sequentially. Are stacked.
As the conductive support (base layer) of the photosensitive drum 21, a conductive material having a volume resistance of 10 ¹⁰ Ωcm or less can be used.

The photosensitive layer of the photosensitive drum 21 can have a laminated structure or a single layer structure.
First, a case where the photosensitive layer has a laminated structure including a charge generation layer and a charge transport layer will be described.
The charge generation layer is a layer mainly composed of a charge generation material. A known charge generation material can be used for the charge generation layer. Specifically, as a charge generating substance, monoazo pigment, disazo pigment, trisazo pigment, perylene pigment, perinone pigment, quinacridone pigment, quinone condensed polycyclic compound, squalic acid dye, other phthalocyanine pigment, na A phthalocyanine pigment, an azulenium salt dye, or the like can be used. These charge generation materials can be used alone or in combination of two or more.
In the charge generation layer, the charge generation material is dispersed in a suitable solvent together with a binder resin as necessary using a ball mill, attritor, sand mill, ultrasonic wave, etc., and this is dispersed on the conductive support (or below). It is formed by applying on the pulling layer and drying. As a coating method of the coating solution, methods such as dip coating, spray coating, beat coating, nozzle coating, spinner coating, ring coating, and the like can be used. The thickness of the charge generation layer is suitably about 0.01 to 5 μm (more preferably about 0.1 to 2 μm).

  The charge transport layer can be formed by dissolving or dispersing the charge transport material and the binder resin in a suitable solvent, and applying and drying the solution on the charge generation layer. If necessary, one or more plasticizers, leveling agents, antioxidants and the like can be added. The amount of the charge transport material is suitably 20 to 300 parts by weight (preferably 40 to 150 parts by weight) with respect to 100 parts by weight of the binder resin. The thickness of the charge transport layer is preferably 25 μm or less from the viewpoint of resolution and responsiveness. The lower limit varies depending on the image forming process (particularly, charging potential), but is preferably 5 μm or more.

Next, a case where the photosensitive layer has a single layer structure will be described.
The photosensitive layer having a single-layer structure is obtained by dissolving or dispersing the above-described charge generating substance, charge transporting substance, binder resin, etc. in an appropriate solvent and coating it on a conductive support (or undercoat layer). It can be formed by drying. You may comprise from a charge generation material and binder resin, without containing a charge transport material. Moreover, a plasticizer, a leveling agent, antioxidant, etc. can also be added as needed.
As the binder resin, in addition to the binder resin used when the charge transport layer is formed, a binder resin used when the charge generation layer is formed may be mixed and used. Furthermore, polymer charge transport materials can also be used favorably. The amount of the charge generating material is preferably 5 to 40 parts by weight with respect to 100 parts by weight of the binder resin, and the amount of the charge transporting material is preferably 0 to 190 parts by weight (more preferably 50 to 150 parts by weight).
The photosensitive layer with a single-layer structure is a dip coating method or spray coating method in which a coating solution in which a charge generating material and a binder resin are dispersed together with a charge transporting material using a solvent such as tetrahydrofuran, dioxane, dichloroethane, and cyclohexane by a dispersing machine. It can be formed by coating with bead coat, ring coat or the like. The film thickness of the photosensitive layer is suitably about 5 to 25 μm.

  The undercoat layer of the photosensitive drum 21 is generally composed mainly of a resin. However, considering that the photosensitive layer is applied with a solvent on these resins, it has a high solvent resistance with respect to a general organic solvent. A resin is desirable. Examples of such resins include water-soluble resins such as polyvinyl alcohol, casein, and sodium polyacrylate, alcohol-soluble resins such as copolymer nylon and methoxymethylated nylon, polyurethane, melamine resin, phenol resin, alkyd-melamine resin, and epoxy. Examples thereof include a curable resin that forms a three-dimensional network structure such as a resin. A fine powder pigment of metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide, and indium oxide may be added to the undercoat layer in order to prevent moire and reduce residual potential. In addition, these undercoat layers can be formed using an appropriate solvent and coating method in the same manner as the photosensitive layer described above. The thickness of the undercoat layer is suitably about 0 to 5 μm.

The protective layer of the photosensitive drum 21 is for reducing mechanical wear on the surface of the photosensitive drum 21.
The protective layer in the present embodiment is formed of a binder resin having a crosslinked structure. The crosslinked structure is a three-dimensional network structure formed by using a reactive monomer having a plurality of crosslinking functional groups in one molecule and causing a crosslinking reaction using light or thermal energy. The binder resin having this network structure exhibits high wear resistance. From the viewpoint of electrical stability, printing durability, and life, a monomer having a charge transporting ability can be used in whole or in part as the reactive monomer. By using such a monomer, a charge transport site is formed in the network structure, and the function as a protective layer is sufficiently exhibited.

Examples of the reactive monomer having charge transporting ability include a compound containing at least one charge transporting component and a silicon atom having a hydrolyzable substituent in the same molecule, and a charge transporting component in the same molecule. A compound containing a hydroxyl group, a compound containing a charge transporting component and a carboxyl group in the same molecule, a compound containing a charge transporting component and an epoxy group in the same molecule, a charge transporting component in the same molecule And a compound containing an isocyanate group can be used. These charge transport materials having a reactive group may be used alone or in combination of two or more.
A reactive monomer having a triarylamine structure can also be used as the monomer having a charge transporting ability because of its high electrical and chemical stability and high carrier mobility.
In addition, monofunctional and bifunctional polymerizable monomers and polymerizable oligomers are used in combination for viscosity adjustment during coating, stress relaxation of the cross-linked charge transport layer, low surface energy, friction coefficient reduction, and other functions. You can also As these polymerizable monomers and oligomers, known ones can be used.

  The protective layer is formed by polymerizing or crosslinking the hole transporting compound using heat or light. When performing the polymerization reaction by heat, there are cases where the polymerization reaction proceeds only with thermal energy and a polymerization initiator is required, but in order to advance the reaction efficiently at a lower temperature, the initiator Is preferably added. In the case of polymerization by light, it is preferable to use ultraviolet light as light, but the reaction rarely proceeds only by light energy, and a photopolymerization initiator is generally used in combination. The polymerization initiator in this case mainly absorbs ultraviolet rays having a wavelength of 400 nm or less, generates active species such as radicals and ions, and initiates polymerization. In addition, it is also possible to use together the heat | fever and photoinitiator mentioned above.

The protective layer having a network structure formed in this manner has high wear resistance, but has a large volume shrinkage during the crosslinking reaction, and may become cracked if it is too thick. In such a case, the protective layer has a laminated structure, a protective layer made of a low molecular weight dispersion polymer is formed on the lower layer (photosensitive layer side), and a protective layer having a crosslinked structure is formed on the upper layer (surface side). You may do it.
As described above, in this embodiment, since the hard protective layer formed of the binder resin having a crosslinked structure is provided on the surface of the photosensitive drum 21, the function as the photosensitive drum 21 is not impaired. In addition, it is possible to prevent the photoconductor film from being scraped by the cleaning blade 25a and the first brush-like roller 25b.

  Referring to FIG. 2, the charging unit 22 is a charging roller formed by covering an outer periphery of a conductive metal core with an intermediate resistance elastic layer. A predetermined voltage is applied to the charging roller 22 from a power supply unit (not shown), thereby uniformly charging the surface of the opposing photosensitive drum 21.

  The developing device (developing unit) 23 mainly faces the first conveying screw 23b via the developing roller 23a facing the photosensitive drum 21, the first conveying screw 23b facing the developing roller 23a, and the partition member 23e. The second conveying screw 23c and a doctor blade 23d facing the developing roller 23a are configured. The developing roller 23a includes a magnet that is fixed inside and forms a magnetic pole on the circumferential surface of the roller, and a sleeve that rotates around the magnet. A plurality of magnetic poles are formed on the developing roller 23a (sleeve) by the magnet, and the developer G is carried on the developing roller 23a.

In the developing device 23, a two-component developer G composed of carrier C and toner T is accommodated.
As the toner T, a spherical toner having a circularity of 0.980 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 where a slight gap between the cleaning blade 25a and the photosensitive drum 21 enters the gap and eventually passes through the gap, resulting in poor cleaning. However, in the present embodiment, the lubricant Q is applied to the surface of the photosensitive drum 21 by the lubricant supply devices 25b and 45 to 49 to improve the toner peelability (removability) on the photosensitive drum 21. The occurrence of defective cleaning is suppressed.

  The cleaning device 25 has a function as a lubricant supply device that supplies a lubricant onto the photosensitive drum 21, as well as an original function of removing deposits such as untransferred toner attached on the photosensitive drum 21. ing. The cleaning device 25 (lubricant supply device) includes a cleaning blade 25a (blade member) that comes into contact with the photosensitive drum 21 (image carrier) and a brush-like rotating member that is provided with brush bristles 25b1 that slide in contact with the photosensitive drum 21. As a brush-like roller 25b, a solid lubricant 45 slidably contacting the brush-like roller 25b, a compression spring 46 urging the solid lubricant 45 toward the brush-like roller 25b, and a removal slidingly contacting the brush bristles 25b1 of the brush-like roller 25b A flicker 47 (plate-like member) as a member, a collection roller 48 (roller-like rotating member) as a collection member for collecting the deposit removed from the brush-like roller 25b by the flicker 47, and a deposit adsorbed on the collection roller 48 are collected. The scraper 49 is configured to be separated from the roller 48.

The cleaning blade 25a as a blade-like member is made of a rubber material such as polyurethane rubber, silicone rubber, nitrile rubber, chloroprene rubber, and is in contact with the surface of the photosensitive drum 21 at a predetermined angle and a predetermined pressure. The cleaning blade 25a preferably has an elastic modulus of about 20 to 80 (%) and a thickness of about 1 to 6 (mm). The cleaning blade 25a mechanically scrapes off deposits such as untransferred toner adhering to the photosensitive drum 21 and collects them in the cleaning device 25. Here, as the deposits adhered to the photosensitive drum 21, in addition to the untransferred toner, paper dust generated from the recording medium P (paper), discharge products generated on the photosensitive drum 21 during discharge by the charging unit 22. And additives added to the toner.
In the present embodiment, the cleaning blade 25 a is in contact with the rotation direction of the photosensitive drum 21 in the counter direction, but the photosensitive member is arranged in the trailing direction with respect to the rotation direction of the photosensitive drum 21. The drum 21 may be contacted.
In addition to the above-described cleaning function, the cleaning blade 25a also has a function as a thinning blade for thinning the lubricant supplied onto the photosensitive drum 21 by the brush roller 25b.

The brush-like roller 25b serving as the brush-like rotating member is a brush-like roller 25b having a length (hair foot) of 0.2 to 20 mm (preferably 0.5 to 10 mm) in which brush hair 25b1 is planted on the base fabric. It is wound around a metal core in a spiral shape, and rotates in the counterclockwise direction of FIG. 2 in a state where the brush bristles 25b1 are in contact with the surface of the photosensitive drum 21.
The brush bristles 25b1 of the brush-like roller 25b are made of resin fibers such as PET (polyethylene terephthalate), nylon, rayon, acrylic, vinylon, polyester, vinyl chloride, and a conductivity-imparting agent such as carbon can be added as necessary. . The brush hair preferably has a brush density of 1 to 50 (10,000 / inch ² ) and a brush resistance of 10 ⁻² to 10 ¹² (Ω · cm). In this embodiment, the brush length is 5 (mm). The brush density is 10 (10,000 / inch ² ) and the brush resistance is 10 ⁵ (Ω · cm). The brush-like roller 25b functions as a cleaning brush that assists in scraping off deposits such as untransferred toner that adhere to the photosensitive drum 21. More specifically, deposits such as untransferred toner adhering to the photosensitive drum 21 are scraped off by the brush roller 25b and then removed by the flicker 47, and then collected in the cleaning device 25 by the collection roller 48. Is done.
The configuration and operation of the lubricant supply device 25b, 45 to 49 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 23a rotates in the direction of the arrow in FIG. The developer G in the developing device 23 is supplied from the toner replenishing portion 32 to the toner replenishing port by the rotation of the first conveying screw 23b and the second conveying screw 23c arranged with the partition member 23e interposed therebetween. It circulates in the longitudinal direction while being agitated and mixed with the toner T replenished through 23f (in the direction perpendicular to the paper surface of FIG. 2).

  Then, the toner T that is frictionally charged and adsorbed on the carrier C is carried on the developing roller 23 a together with the carrier C. The developer G carried on the developing roller 23a then reaches the position of the doctor blade 23d. The developer G on the developing roller 23a is adjusted to an appropriate amount at the position of the doctor blade 23d, and then reaches a position facing the photosensitive drum 21 (developing area).

  Thereafter, in the development area, the toner T in the developer G adheres to the electrostatic latent image formed on the surface of the photosensitive drum 21. Specifically, the toner T is latently exposed by the electric field formed by the potential difference (development potential) between the latent image potential (exposure potential) of the image area irradiated with the laser light L and the development bias applied to the development roller 23a. Adhere to the image.

  Thereafter, most of the toner T adhering to the photosensitive drum 21 in the developing process is transferred onto the intermediate transfer belt 27. The untransferred toner T remaining on the photosensitive drum 21 is collected in the cleaning device 25 by the cleaning blade 25a and the brush-like roller 25b.

  Here, a toner replenishing unit 32 provided in the apparatus main body 1 includes a toner bottle 33 configured to be replaceable, and a toner hopper unit 34 that holds and rotates the toner bottle 33 and replenishes the developing device 23 with new toner T. And is composed of. Also, a new toner T (any one of yellow, magenta, cyan, and black) is accommodated in the toner bottle 33. In addition, a spiral protrusion is formed on the inner peripheral surface of the toner bottle 33.

  The new toner T in the toner bottle 33 is appropriately replenished into the developing device 23 from the toner replenishing port 23f as the toner T (existing toner) in the developing device 23 is consumed. . The toner T in the developing device 23 is consumed indirectly or directly by the reflective photosensor 41 facing the photosensitive drum 21 and the magnetic sensor 40 installed below the second conveying screw 23c of the developing device 23. Detected.

  Here, in the present embodiment, the toner density (TC) is controlled to be within a predetermined range. Specifically, toner replenishment is performed so that the detection results of the magnetic sensor 40 and the reflection type photosensor 41 have an output value corresponding to the above-described toner density range (the ratio of the toner T in the developer G). The toner is supplied from the unit 32 to the developing device 23 through the toner supply port 23f.

Hereinafter, the configuration and operation of the lubricant supply device, which is characteristic in the present embodiment, will be described in detail.
Referring to FIGS. 2 and 3, the lubricant supply device is integrally installed in the cleaning device 25. The lubricant supply device includes a cleaning blade 25a that contacts the photosensitive drum 21, a brush-like roller 25b as a brush-like rotating member around which brush bristles 25b1 that slide in contact with the photosensitive drum 21 and the solid lubricant 45 are provided, a solid roller A lubricant 45, a compression spring 46 that urges the solid lubricant 45 toward the brush-like roller 25b, a flicker 47 (plate-like member) as a removing member that removes deposits attached to the brush-like roller 25b, and a flicker 47 A recovery roller 48 (roller-like rotating member) as a recovery member for recovering the deposit removed from the brush-like roller 25b, a scraper 49 for separating the deposit adsorbed on the recovery roller 48 from the recovery roller 48, and the like.
In addition to the original cleaning function, the cleaning blade 25a also has a function of thinning the lubricant supplied to the photosensitive drum 21 by the brush roller 25b.

The brush-like roller 25b is disposed on the upstream side in the rotation direction (traveling direction) of the photosensitive drum 21 with respect to the cleaning blade 25a.
The brush-like roller 25b has a spiral shape on a metal core, which is obtained by planting brush hairs 25b1 having a length (hair feet) in the range of 0.2 to 20 mm (preferably 0.5 to 10 mm) on a base fabric. It is wrapped around. The brush-like roller 25b is arranged so that the brush bristles 25b1 bite into the photosensitive drum 21 by a predetermined amount.
When the length of the brush bristles 25b1 exceeds 20 mm, the brush bristles 25b1 fall down in a predetermined direction due to repeated rubbing with the photosensitive drum 21, the solid lubricant 45, and the flicker 47 over time. Scraping ability is reduced. On the other hand, if the length of the brush bristles 25b1 is less than 0.2 mm, the physical contact force with respect to the solid lubricant 45 will be insufficient. Therefore, the length of the brush bristles 25b1 is preferably in the above range.

The brush roller 25b rotates in the opposite direction to the photosensitive drum 21 rotating in the clockwise direction in FIG. 2 (rotation in the counterclockwise direction in FIG. 2). The brush-like roller 25b is disposed so as to be in sliding contact with the solid lubricant 45, and the brush-like roller 25b rotates to scrape the lubricant Q from the solid lubricant 45 and remove the lubricant Q from the photoconductor. It is applied on the drum 21 (see also FIG. 3).
A compression spring 46 is disposed behind the solid lubricant 45 in order to eliminate contact unevenness between the brush roller 25b and the solid lubricant 45, and urges the solid lubricant 45 to the brush roller 25b. Yes.

In the present embodiment, the solid lubricant 45 is formed of zinc stearate. Specifically, the solid lubricant 45 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 21 can be made low in friction. That is, the surface of the photosensitive drum 21 can be effectively covered with a small amount of lubricant by the lamellar crystal that uniformly receives the shearing force and covers the surface of the photosensitive drum 21.

  In addition to the zinc stearate, the solid lubricant 45 includes stearic acid groups such as barium stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate, and calcium stearate. 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.

Referring to FIG. 3, flicker 47 as a removal member is a plate-like member made of stainless steel or the like that is in sliding contact with brush bristles 25b1 of brush-like roller 25b, and brush bristles 25b1 toward the rotation center of brush-like roller 25b. It is arrange | positioned so that it may bite into. The flicker 47 is disposed on the downstream side in the rotational direction of the brush roller 25b with respect to the position where the brush roller 25b and the photosensitive drum 21 are opposed to each other. The flicker 47 removes deposits such as toner T collected from the photosensitive drum 21 by the brush roller 25b from the brush roller 25b.
As described above, the brush-like roller 25b removes deposits such as toner T (untransferred toner) adhered on the photosensitive drum 21 in addition to the function of supplying the lubricant Q onto the photosensitive drum 21. It has a function. Then, the brush bristles 25b1 of the brush-like roller 25b to which the toner T is adhered are bent at the position of the flicker 47 in the direction opposite to the rotation direction (after falling down), and then slip through the position of the flicker 47 and vigorously. It will be restored (standing up). At this time, an urging force is generated when the brush bristles 25b1 are restored, and the toner T (adhered matter) carried on the brush-like roller 25b flies and the toner T (adhered matter) is removed from the brush-like roller 25b. Will be.

Here, in the present embodiment, the brush-like roller is provided by the flicker 47 on the downstream side in the rotational direction of the brush-like roller 25b with respect to the flicker 47 and on the upstream side in the rotational direction of the brush-like roller 25b with respect to the solid lubricant 45. A collecting roller 48 is disposed as a collecting member for collecting the toner T (adhered matter) removed from 25b.
The collection roller 48 is a roller-like rotating member in which an elastic layer having a medium resistance (about 1 to 10 ⁶ ohms) is formed on a cored bar, and a predetermined voltage is applied from the power supply unit 50 to the cored bar. As a result, the toner T (attachment) is electrically adsorbed. In this way, the toner T (adhered matter) removed from the brush-like roller 25 b by the flicker 47 is actively collected by the collecting roller 48, so that the toner T (adhered matter) removed by the flicker 47 becomes a solid lubricant 45. The problem of adhering and entering between the solid lubricant 45 and the brush roller 25b can be reliably prevented. Therefore, the amount of the lubricant Q scraped off from the solid lubricant 45 by the brush roller 25b is reduced, and the amount of the lubricant Q supplied from the brush roller 25b onto the photosensitive drum 21 is reduced. It is possible to prevent problems such as poor cleaning and filming on the photosensitive drum 21.

In this embodiment, in order to improve the collection efficiency of the deposits by the collection roller 48 described above, the rotation direction of the collection roller 48 is the same as the rotation direction of the brush roller 25b (the counter direction). It is set.
The collection roller 48 is disposed so as to face the brush roller 25b in a non-contact manner. Thereby, compared with the case where the collection | recovery roller 48 is made to contact with the brush-like roller 25b, since the load concerning the bristle 25b1 of the brush-like roller 25b decreases, durability of the brush-like roller 25b improves.
Further, a scraper 49 (a thin plate made of stainless steel or the like) for separating the toner T (adhered matter) adsorbed on the collection roller 48 from the collection roller 48 is in contact with the surface of the collection roller 48. With such a configuration, the toner T (adhered matter) collected by the collection roller 48 is removed by the scraper 49 and then discharged to the outside of the cleaning device 25 by the collection screw 70.

Hereinafter, the mechanism by which the toner is removed from the brush roller 25b toward the collection roller 48 will be described in detail.
The toner T used in the present embodiment is charged to a negative polarity and is attached to the electrostatic latent image on the photosensitive drum 21 by the developing device 23. Therefore, in order to transfer the toner from the photosensitive drum 21 onto the intermediate transfer belt 27, an electric field is formed between the photosensitive drum 21 and the transfer bias roller 24 by applying a positive voltage to the transfer bias roller 24. Will do. At this time, all of the toner on the photosensitive drum 21 is not transferred to the intermediate transfer belt 27, and if the toner adheres strongly to the photosensitive drum 21, it remains on the photosensitive drum 21 as untransferred toner. To do. The untransferred toner on the photosensitive drum 21 is affected by the transfer current, and the charge polarity changes from the negative polarity, which is the normal charge polarity, to the positive polarity.
From such a mechanism, the brush bristles 25b1 of the brush-like roller 25b are made of high-resistance resin fibers (for example, PET) that are frictionally charged to the same polarity as the polarity of the toner T (in this embodiment, negative polarity). It is preferable to form it. That is, since the untransferred toner on the photosensitive drum 21 is charged with a positive polarity, the brush bristles 25b1 of the brush-like roller 25b are brought into sliding contact with the photosensitive drum 21, so that the brush bristles 25b1 are charged with a negative polarity. The positive polarity untransferred toner can be electrostatically adsorbed to the brush bristles 25b1. Therefore, the untransferred toner adhering to the photosensitive drum 21 can be efficiently collected by the brush-like roller 25b.

  Thereafter, the untransferred toner T collected by the brush-like roller 25b flies away from the brush-like roller 25b by the flicker 47 in the direction of the arrow in FIG. 3 as described above with reference to FIG. At this time, an electric field is formed between the collection roller 48 and the brush-like roller 25b by applying a negative polarity voltage from the power supply unit 50 to the core of the collection roller 48, and the brush-like roller is generated by the action of the electric field. The positive polarity toner flying from 25 b adheres to the collecting roller 48. Thereafter, the toner T adhering to the collection roller 48 is mechanically scraped off by the scraper 49 and is once collected in the cleaning device 25, and then conveyed to the outside by the collection screw 70.

Here, the problem in the conventional lubricant supply device will be described with reference to FIG.
As shown in FIG. 4, the rotation direction of the brush-like roller 25b is opposite to the rotation direction of the photosensitive drum 21, and the brush bristles 25b1 come into contact with the flicker 47 to be opposite to the rotation direction of the brush-like roller 25b. Tumble in the direction. When the brush roller 25b further rotates in this state, the brush bristles 25b1 pass through the flicker 47 and fall down in the same direction as the rotation direction of the brush roller 25b by the repulsive force. At this time, the toner T adhering to the brush-like roller 25b flies by the repulsive force of the brush bristles 25b1 and is removed from the brush-like roller 25b.
However, the toner T removed from the brush-like roller 25b flies toward the solid lubricant 45, scatters to a contact portion (nip portion) between the solid lubricant 45 and the brush-like roller 25b, and stays at that position. As a result, the ability of the brush roller 25b to scrape off the lubricant is reduced. As described above, when the toner stays between the solid lubricant 45 and the brush roller 25b, the amount of the lubricant Q scraped off by the brush roller 25b decreases, and the amount of lubricant supplied to the photosensitive drum 21 decreases. Resulting in.

  On the other hand, in the present embodiment, since the collection roller 48 is provided between the flicker 47 and the solid lubricant 45 and the toner T flying by the flicker 47 is actively collected, the solid lubricant The problem that the toner T flies and stays between the roller 45 and the brush-like roller 25b is reliably suppressed.

  As described above, according to the present embodiment, the toner T (attached) removed from the brush-like roller 25b (brush-like rotating member) by the flicker 47 between the flicker 47 (removing member) and the solid lubricant 45. A collection roller 48 (collection member) for collecting the kimono) is provided. As a result, the toner T (attachment) removed from the brush-like roller 25b by the flicker 47 does not adhere to the solid lubricant 45, and the lubricant Q is stably applied onto the photosensitive drum 21 (image carrier). Can be supplied.

In the present embodiment, the cleaning device 25 (lubricant supply device) is integrated with the photosensitive drum 21 and the charging unit 22 to form the process cartridge 20 so that the image forming unit can be made compact and maintenance workability can be improved. We are trying to improve. Thus, in a compact process cartridge, a lubricant supply device having a small number of parts and a simple configuration as in the present embodiment is particularly useful.
In addition, the cleaning device 25 (lubricant supply device) can be configured to be replaceable in the apparatus main body 1 as a single unit 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 an image forming apparatus equipped with a two-component developing type developing device 23 using a two-component developer. However, a one-component developing type using a one-component developer is used. Of course, the present invention can also be applied to an image forming apparatus equipped with the developing device 23.
Further, in the present embodiment, the present invention is applied to a lubricant supply device that supplies a lubricant to the photosensitive drum 21 as an image carrier. However, the present invention is applied to a photosensitive belt or an intermediate transfer belt as an image carrier. Naturally, the present invention can also be applied to a lubricant supply device that supplies a lubricant.

  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. Further, 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 that are suitable for implementing the present invention can be used.

1 is an overall configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating an image forming unit in the image forming apparatus of FIG. 1. It is an enlarged view which shows the principal part of a lubricant supply apparatus. It is an enlarged view which shows the principal part of the conventional lubricant supply apparatus.

Explanation of symbols

1 image forming apparatus body (apparatus body),
20, 20Y, 20M, 20C, 20BK Process cartridge,
21 photosensitive drum (image carrier), 22 charging unit,
23, 23Y, 23M, 23C, 23BK Developing device (developing unit),
25 Cleaning device (lubricant supply device),
25a Cleaning blade,
25b brush-like roller (brush-like rotating member),
25b1 brush hair,
45 solid lubricant,
46 compression spring,
47 Flicker (removal member, plate-like member),
48 collection roller (collection member, roller-like rotating member),
49 Scraper,
50 Power supply, Q Lubricant,
G Two-component developer (developer), T toner, C carrier.

Claims (12)

A lubricant supply device for supplying a lubricant onto an image carrier,
A brush-like rotating member having brush bristles in sliding contact with the image carrier and the solid lubricant;
A removing member for removing the adhered matter attached to the brush-like rotating member;
With
Removed from the brush-like rotating member by the removing member on the downstream side in the rotational direction of the brush-like rotating member with respect to the removing member and upstream in the rotational direction of the brush-like rotating member with respect to the solid lubricant A lubricant supply device comprising a recovery member for recovering deposits.   The recovery member is a roller-like rotating member in which an intermediate-resistance elastic layer is formed on a cored bar, and electrically attracts the deposit by applying a predetermined voltage to the cored bar. The lubricant supply device according to claim 1, wherein   The lubricant supply device according to claim 2, wherein a scraper for separating the adhering matter adsorbed on the roller-like rotating member from the roller-like rotating member is brought into contact with the roller-like rotating member.   4. The lubricant supply device according to claim 2, wherein the roller-shaped rotating member rotates in the same direction as a rotation direction of the brush-shaped rotating member. 5.   The lubricant supply device according to any one of claims 1 to 4, wherein the recovery member is disposed so as to face the brush-like rotating member in a non-contact manner.   6. The lubricant according to claim 1, wherein the brush bristles of the brush-like rotating member are formed of high-resistance resin fibers that are frictionally charged to the same polarity as the polarity of the toner. Feeding device.   The lubricant supply device according to any one of claims 1 to 6, wherein the removing member is a plate-like member that is in sliding contact with the brush bristles of the brush-like rotating member.   The lubricant supply device according to claim 1, wherein the solid lubricant is zinc stearate.   9. The image bearing member according to claim 1, further comprising a protective layer having a crosslinked structure and formed of a binder resin formed by dispersing a charge transport material on a surface thereof. Lubricant supply device. The lubricant supply device according to any one of claims 1 to 9,
A cleaning apparatus comprising a cleaning blade for cleaning the image carrier on the downstream side in the running direction of the image carrier relative to the lubricant supply device. A process cartridge that is detachably installed on the main body of the image forming apparatus,
10. A process cartridge, wherein the lubricant supply device according to claim 1 and the image carrier are integrated.   An image forming apparatus comprising the lubricant supply device according to claim 1 and the image carrier.

Images