JP2020067570A - Image forming apparatus and solid lubricant - Google Patents

Abstract

To make it possible to predict the amount of usage of and time to replace a lubricant.SOLUTION: An image forming apparatus comprises: a rotatable photoreceptor drum; a solid lubricant 721 that extends in the direction of the axis of rotation of the photoreceptor drum; an application brush 71 that has the axis of rotation parallel to the axis of rotation of the photoreceptor drum, and rotates while being brought into contact with the solid lubricant 721 and photoreceptor drum to supply a lubricant scraped off from the solid lubricant 721 to the photoreceptor drum; a motor that rotates the application brush 71; and control means that controls the amount of lubricant on the photoreceptor drum. The solid lubricant 721 is configured such that a variation occurs in torque of the application brush 71 in a predetermined condition according to the amount of usage of the solid lubricant 721, and the image forming apparatus includes detection means that detects a value changing due to the variation in torque of the application brush 71 in the predetermined condition.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an image forming apparatus and a solid lubricant.

  In an electrophotographic image forming apparatus, a cleaning blade or the like is slidably brought into contact with the surface of an image carrier (for example, a photosensitive drum) on which a toner image is formed, so that the residue attached on the surface of the image carrier is retained. Adhesive substances such as toner are removed (cleaned). In cleaning the image bearing member, a technique of applying a lubricant to the image bearing member is used in order to reduce the adhesive force of the toner to the image bearing member and improve the cleaning performance.

  It is known that the amount of the lubricant adhered on the surface of the image carrier greatly affects the cleaning performance. For example, when the amount of lubricant adhered is exhausted, residual toner or the like tends to adhere to the surface of the image carrier, which makes it difficult to clean the toner, the toner slips through the cleaning blade, or the edge portion of the cleaning blade. Are drawn in the moving direction (rotational direction) of the image carrier and turn up. On the other hand, when the amount of the lubricant adhered becomes excessive, the surface of the image carrier becomes a mirror surface, and the adhesion between the surface of the image carrier and the tip of the cleaning blade becomes high, so that the amount of the tip pulled in is increased. As a result, the edge of the cleaning blade is worn more.

Therefore, an image forming apparatus has been proposed in which the amount of the lubricant supplied to the image carrier is adjusted according to the magnitude of the torque of the motor that drives the image carrier (see Patent Document 1).
Further, there is proposed an image forming apparatus that detects the rotation torque of a rotating brush that applies a lubricant to an image carrier and controls the rotation speed of the rotating brush from the rotation torque (see Patent Document 2).

  In addition, the image forming apparatus detects a cleaning failure due to abrasion of the cleaning blade to predict the life (use limit) of the cleaning blade, and determines the life of the photosensitive layer of the photoconductor. In recent years, the life of each component has been extended, and the lubricant reaches the replacement time first. Conventionally, the lubricant is increased in order to prolong the period of use, or it is judged that the lubricant has run out by forming a predetermined number of images, and the lubricant is replaced.

Further, in a lubricant applying device that applies a lubricant to the surface of a rotating body, there is a technique for determining the remaining amount of the lubricant based on the value of a current flowing between the rotating body and the lubricant holder via the lubricant. It is used (see Patent Document 3).
In addition, a lubricant supply device that detects when a pair of rotating members, which are rotatably supported by a holding member that holds a lubricant, has rotated to a predetermined position, and detects the replacement timing of the lubricant, is provided. It has been proposed (see Patent Document 4).

JP, 2011-232570, A JP, 2010-210799, A JP, 2011-107592, A Japanese Unexamined Patent Publication No. 2012-103531

  However, in order to make the lubricant large, there is a space limitation, and if the life of the lubricant is judged with a predetermined number of sheets, there will be a large error, and the lubricant will have to be replaced before it reaches the end of its life. However, there is a problem that the lubricant is exhausted before it is judged to be the end of life, and an image defect due to poor cleaning or blade flipping occurs.

For example, in Patent Document 2, the rotation speed of the rotating brush is controlled in order to adjust the amount of the lubricant on the image bearing member to an appropriate amount, but the rotation speed of the brush changes depending on the coverage and the environment. Since the amount of the lubricant supplied to the image carrier changes, there is a large error in determining the life using a predetermined table or the like.
Further, the technique described in Patent Document 1 does not detect the life of the lubricant.

Further, in the method of detecting the current value flowing between the rotating body and the lubricant holder as in Patent Document 3, a means for detecting the current flowing through the holder is additionally required, and the lubricant reaches the limit of use. Until the last minute, the usage status could not be grasped, and it was insufficient as information on the usage amount of the lubricant on the way.
Further, in the technique described in Patent Document 4, not only the lubricant is pressed by the spring, but also a rotating member needs to be provided separately, and there is little information about the amount of the lubricant used in the middle, and the limit of use is limited. It could not be detected without approaching.

  The present invention has been made in view of the above-described problems in the conventional art, and an object thereof is to make it possible to predict the amount of lubricant used and the replacement time.

  In order to solve the above-mentioned problems, the invention according to claim 1 is such that a rotatable image carrier, a solid lubricant extending in a rotation axis direction of the image carrier, and a rotation shaft of the image carrier. A lubricant supply member that has parallel rotation axes and that supplies the lubricant scraped from the solid lubricant to the image carrier by rotating in contact with the solid lubricant and the image carrier. An image forming apparatus comprising: a motor that rotates the lubricant supply member; and a control unit that controls the amount of the lubricant on the image bearing member, wherein the solid lubricant is the solid lubricant. It is configured such that the torque of the lubricant supply member varies under a predetermined condition in accordance with the usage amount, and includes a detection unit that detects a value that changes due to the torque fluctuation of the lubricant supply member under the predetermined condition. .

  According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the solid lubricant has a plurality of lubricants having different hardness along a direction in which the solid lubricant is scraped off by the lubricant supply member and becomes smaller. It is composed of layers of agents.

  According to a third aspect of the present invention, in the image forming apparatus according to the first aspect, the solid lubricant is provided with the lubricant supply member along a direction in which the solid lubricant is scraped off by the lubricant supply member and becomes smaller. Is configured so that the contact area thereof changes.

  According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect, the solid lubricant is orthogonal to the extending direction of the solid lubricant at some or all positions in the extending direction. In the cross section of the solid lubricant, the width of the solid lubricant that is orthogonal to the direction is different along the direction in which the solid lubricant is scraped off by the lubricant supply member and becomes smaller.

  According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects, the detecting unit supplies a current value of the motor or the lubricant supply obtained from the current value. Detect the torque of the member.

  According to a sixth aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects, the control unit adjusts the lubricant supplied to the image bearing member, thereby performing the image bearing. Controls the amount of lubricant on the body.

  According to a seventh aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects, the control unit adjusts the thickness of the lubricant on the image carrier, Control the amount of lubricant on the image carrier.

  According to an eighth aspect of the present invention, in the image forming apparatus according to any one of the first to seventh aspects, the control unit adjusts the number of rotations of the lubricant supply member, thereby the image carrier. Control the amount of lubricant on.

  According to a ninth aspect of the present invention, in the image forming apparatus according to any one of the first to eighth aspects, the usage amount or the remaining amount of the solid lubricant is calculated from the value detected by the detection unit, A notification unit for notifying the usage amount or the remaining amount of the solid lubricant is provided.

  According to a tenth aspect of the present invention, in the image forming apparatus according to any one of the first to ninth aspects, a value that changes due to a torque fluctuation of the lubricant supply member under the predetermined condition is one of the explanatory variables. , A machine learning result obtained by machine learning using the usage amount or the remaining amount of the solid lubricant as an objective variable is prepared in advance, and based on the value detected by the detecting means, the solid lubricant is obtained from the machine learning result. And a predicting means for predicting the replacement time of the solid lubricant.

  According to an eleventh aspect of the present invention, in the image forming apparatus according to any one of the first to tenth aspects, the detection unit detects a value that changes due to a torque fluctuation of the lubricant supply member under the predetermined condition. Mode is provided.

  According to a twelfth aspect of the present invention, the lubricant is scraped off by rotating the lubricant supply member in a state of extending in the rotation axis direction of the lubricant supply member and being in contact with the lubricant supply member. The solid lubricant to be used is configured such that the torque of the lubricant supply member varies under a predetermined condition depending on the amount of the solid lubricant used.

  According to the present invention, it is possible to predict the amount of lubricant used and the replacement time.

FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a block diagram showing a main functional configuration of the image forming apparatus. It is a figure which shows the structure of each image forming part. It is an enlarged view showing composition of a cleaning device and a lubricant application mechanism. It is a figure for demonstrating the structure of the specific example 1 of a solid lubricant. 6 is a graph showing torque fluctuations of a coating brush when a specific example 1 of a solid lubricant is used. It is a graph which shows the torque fluctuation of the application brush in a comparative example. It is a figure for demonstrating the structure of the specific example 2 of a solid lubricant. 6 is a graph showing torque fluctuations of a coating brush when a specific example 2 of a solid lubricant is used. It is a figure for demonstrating the structure of the specific example 3 of a solid lubricant. 7 is a graph showing torque fluctuations of a coating brush when a specific example 3 of a solid lubricant is used. It is a figure for demonstrating the structure of the comparative example of the specific example 3 of a solid lubricant. 6 is a flowchart showing an image forming process executed by the image forming apparatus. It is a flow chart which shows lubricant amount detection processing. 6 is a graph showing an example of average fluctuations in torque of a coating brush with respect to the number of image formations and measured values. 6 is a graph showing another example of the average variation of the torque of the coating brush with respect to the number of images formed and the measured values. 8 is a graph showing torque fluctuations of a coating brush with respect to the number of images formed in the image forming apparatus according to the second embodiment.

[First Embodiment]
Hereinafter, a first embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. The present invention is not limited to the illustrated example.

FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus 100 according to the first embodiment. FIG. 2 is a block diagram showing a main functional configuration of the image forming apparatus 100. The image forming apparatus 100 forms an image on a recording medium such as a sheet by an electrophotographic image forming process.
The image forming apparatus 100 includes an image forming unit 10, a control unit 20, a paper feeding unit 21, an image reading unit 22, a display unit 23, an operation unit 24, and a storage unit 25. There is.

  The image forming unit 10 includes a yellow image forming unit 11Y, a magenta image forming unit 11M, a cyan image forming unit 11C, a black image forming unit 11K, an intermediate transfer belt 12, a secondary transfer roller 13, and a fixing device 14. And are provided.

  The image forming units 11Y, 11M, 11C and 11K are arranged in series (tandem) along the belt surface of the intermediate transfer belt 12 and form toner images of respective colors on the intermediate transfer belt 12. The image forming units 11Y, 11M, 11C, and 11K have the same configuration except that the colors of the toner images to be formed are different.

  FIG. 3 shows the configuration of each of the image forming units 11Y, 11M, 11C and 11K. Each of the image forming units 11Y, 11M, 11C and 11K includes a photosensitive drum 1 (image carrier), a charging device 2, an exposure device 3, a developing device 4, a primary transfer roller 5, and a cleaning device 6. And a lubricant applying mechanism 7.

  The photosensitive drum 1 is rotationally driven in the direction A shown in FIG. 3, and carries an electrostatic latent image and a toner image on its surface layer. The photoconductor drum 1 is composed of, for example, an organic photoconductor in which a photosensitive layer made of a resin containing an organic photoconductor is formed on the outer peripheral surface of a drum-shaped metal substrate. Examples of the resin constituting the photosensitive layer include polycarbonate resin, silicone resin, polystyrene resin, acrylic resin, methacrylic resin, epoxy resin, polyurethane resin, vinyl chloride resin, melamine resin and the like.

  The charging device 2 uses a charging roller to uniformly charge the surface of the photosensitive drum 1. It is preferable to use a charging roller because the photosensitive drum 1 can be uniformly charged to a constant potential, but a corotron charger, a scorotron charger or the like may be used as the charging device 2.

  The exposure device 3 exposes the surface of the photosensitive drum 1 charged by the charging device 2 on the basis of the image data Dy, Dm, Dc, and Dk of each color of yellow, magenta, cyan, and black to form an electrostatic latent image. Form.

  The developing device 4 visualizes the electrostatic latent image formed by the exposure device 3 using a developer containing toner. The developing device 4 includes a developing sleeve 41 which is arranged so as to face the photoconductor drum 1 via a developing area, and adheres toner to the electrostatic latent image on the photoconductor drum 1 to form a toner image.

  The toner in the developer can be produced by a commonly used known method, for example, a pulverization method, an emulsion polymerization method, a suspension polymerization method, or the like. Examples of the binder resin used in the toner include styrene-based resins (styrene, or homopolymers or copolymers containing styrene substitution products), polyester resins, epoxy-based resins, vinyl chloride resins, phenol resins, polyethylene. Resin, polypropylene resin, polyurethane resin, silicone resin and the like can be mentioned. The binder resin made of these resin simple substances or composites preferably has a softening temperature in the range of 80 to 160 ° C or a glass transition point in the range of 50 to 75 ° C.

  As the colorant of the toner, it is possible to use a commonly used known one, for example, carbon black, aniline black, activated carbon, magnetite, benzine yellow, permanent yellow, naphthol yellow, phthalocyanine blue, fast sky blue, ultra. Examples include marine blue, rose bengal, and lake red. Then, it is preferable to use the colorant in a ratio of 2 to 20 parts by weight with respect to 100 parts by weight of the binder resin described above.

  As the charge control agent contained in the binder resin, for positively chargeable toner, for example, nigrosine dye, quaternary ammonium salt compound, triphenylmethane compound, imidazole compound, polyamine resin, etc. are used. In the case of negatively chargeable toner, metal-containing azo dyes such as chromium, cobalt, aluminum and iron, salicylic acid metal compounds, alkylsalicylic acid metal compounds, and carlix allene compounds are used. This charge control agent is preferably used in a proportion of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. Further, as the release agent contained in the binder resin, for example, polyethylene, polypropylene, carnauba wax, sazol wax and the like are used alone or in combination of two or more kinds, and the amount is 0.1% with respect to 100 parts by weight of the binder resin. It is preferably used in a ratio of 1 to 10 parts by weight.

  From the viewpoint of improving the charging performance, fluidity, or cleaning property of the toner, known particles such as inorganic particles and organic particles can be added to the surface of the toner base particles as an external additive. As these external additives, various kinds may be used in combination.

  The inorganic fine particles include inorganic oxide fine particles such as silica, titania and alumina; inorganic stearate compound fine particles such as aluminum stearate fine particles and zinc stearate fine particles; or inorganic fine particles such as calcium titanate, strontium titanate and zinc titanate. Inorganic fine particles such as fine particles of a titanic acid compound are preferred. Among these, fine particles of inorganic titanate compound (fine particles of metal oxide) such as strontium titanate and calcium titanate are characterized by having a high polishing effect. Examples of the silica particles include colloidal silica, hydrolyzate of alkoxysilane (silica produced by sol-gel method), silica produced by a wet method such as precipitated silica, fumed silica, and dry method such as fused silica. The silica or the like manufactured in 1. is used.

  If necessary, these inorganic fine particles may be treated with a silane coupling agent, a titanium coupling agent, a higher fatty acid, a silicone oil, etc. for gloss treatment and hydrophobic treatment in order to improve heat-resistant storage stability and environmental stability. Etc. may be performed. From the viewpoint of improving the fluidity of the external additive, it is preferable to use silica particles that have been hydrophobized (surface treated) with hexamethyldisilazane (HMDS) or the like.

  As these inorganic fine particles, it is preferable to use spherical inorganic fine particles having a number average primary particle diameter of about 5 nm to 2 μm with or without hydrophobic treatment. The number average primary particle diameter of the inorganic fine particles can be calculated using an electron microscope photograph. Specifically, a 30,000 times photograph of the toner sample is taken with a scanning electron microscope, and this photograph image is used. Is captured by a scanner. The image processing analysis device LUZEX (registered trademark) AP (manufactured by Nireco Co., Ltd.) binarizes the external additives present on the toner surface of the photographic image, and the horizontal direction of 100 external additives per one kind. The Feret's diameter was calculated, and the average value was taken as the number average particle diameter.

  As the inorganic fine particles, two kinds of particles having different number average primary particle diameters (for example, silica particles) may be used. For example, the number average primary particle diameter of the larger particle diameter is preferably 60 to 250 nm, and more preferably 80 to 200 nm. Within such a range, the adhesion of the larger particles to the toner base particles can be promoted, and the stability of the charge amount and the cleaning property can be improved. The number average primary particle diameter of the smaller particle diameter is preferably 5 to 45 nm, more preferably 12 to 40 nm. Within such a range, good chargeability of the small-diameter silica particles can be sufficiently obtained, and by facilitating uniform adhesion on the surface of the toner base particles, the initial charge amount and The stability of the charge amount can be improved.

  As the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 nm to 2 μm can be used. Specifically, it is possible to use a homopolymer of styrene, methyl methacrylate, or the like, or organic fine particles of a copolymer thereof. The number average primary particle diameter of the organic fine particles can be calculated by using an electron micrograph similarly to the number average primary particle diameter of the inorganic fine particles.

The addition amount of the external additive is preferably 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the toner particles.
Examples of the method of adding the external additive include a method of adding using various known mixing devices such as a Turbuler mixer, a Henschel mixer, a Nauter mixer, and a V-type mixer.

  As the carrier, a binder type carrier, a coat type carrier, or the like is used, and the carrier particle size is not limited, but is preferably 15 to 100 μm. The mixing ratio of the toner and the carrier may be adjusted so as to obtain a desired toner charge amount, and the toner ratio with respect to the total amount of the toner and the carrier is preferably adjusted to 3 to 30% by weight. To be done. Further, the toner ratio is more preferably 4 to 20% by weight.

  The binder type carrier is one in which magnetic fine particles are dispersed in a binder resin, and is also constituted by fixing positive or negative chargeable chargeable fine particles to the carrier surface or providing a surface coating layer. The charging characteristics of the binder type carrier are controlled by the material of the binder resin, the chargeable fine particles and the type of the surface coating layer. As the binder resin, a vinyl resin represented by polystyrene resin, a polyester resin, a nylon resin, a thermoplastic resin such as a polyolefin resin, a thermosetting resin such as a phenol resin, or the like is used.

  Examples of the magnetic fine particles dispersed in the binder type carrier include spinel ferrite such as magnetite and gamma iron oxide, and spinel ferrite containing one or more metals (manganese, nickel, magnesium, copper, etc.) other than iron. Magnetoplumbite type ferrite such as barium ferrite, iron or alloy particles having iron oxide on the surface, or the like is used. At this time, when high magnetization is required, it is preferable to use iron-based ferromagnetic fine particles. On the other hand, in consideration of chemical stability, it is preferable to use ferromagnetic fine particles such as spinel ferrite and magnetoplumbite ferrite. Then, the carrier having a desired magnetization can be obtained by appropriately selecting the type and content of the ferromagnetic fine particles. The shape of the magnetic fine particles may be granular, spherical, or needle-shaped. Furthermore, it is suitable to add the magnetic fine particles to the carrier in an amount of 50 to 90% by weight.

  In the case of a binder type carrier in which charged fine particles or conductive fine particles are fixed on the surface, for example, mechanical and thermal impact force is applied after uniformly mixing and attaching the above fine particles to the magnetic resin carrier on the carrier surface. By applying, the fine particles are fixed by being driven into the magnetic resin carrier on the carrier surface. At this time, the fine particles are not completely embedded in the magnetic resin carrier, but a part of them are fixed so as to protrude from the surface of the magnetic resin carrier.

  When the chargeable fine particles are used as the fine particles, an organic or inorganic insulating material is used. Specifically, for example, polystyrene, styrene-based copolymers, acrylic resins, various acrylic copolymers, nylon, polyethylene, polypropylene, fluororesins and organic insulating fine particles such as cross-linked products thereof, the material, polymerization By appropriately selecting the catalyst, surface treatment, etc., the charge level and polarity of the carrier can be set as desired. As the inorganic fine particles, for example, negatively chargeable inorganic fine particles such as silica and titanium dioxide, and positively chargeable inorganic fine particles such as strontium titanate and alumina are used.

  In the case of a binder type carrier provided with a surface coating layer, for example, a silicone resin, an acrylic resin, an epoxy resin, a fluorinated resin or the like is used as the surface coating material forming the surface coating layer. By thus forming the surface coating layer in which the surface is coated with the resin material and cured, the charge imparting ability can be improved.

  On the other hand, the coat type carrier is a carrier constituted by coating carrier core particles made of a magnetic material with a coat resin, and in the coat type carrier as well as the binder type carrier, positive or negative charging electrostatic fine particles are formed on the carrier surface. Can be fixed. The charging characteristics such as polarity of the coat type carrier are controlled by the type of surface coating layer and the type of chargeable fine particles, and the same material as the binder type carrier can be used as the material. As the coat resin for coating the carrier core particles, the same resin as the binder resin for the binder type carrier is used.

  The primary transfer roller 5 transfers (primarily transfers) the toner image formed on the photosensitive drum 1 to the intermediate transfer belt 12 that moves in the direction B shown in FIG.

FIG. 4 is an enlarged view showing the configurations of the cleaning device 6 and the lubricant applying mechanism 7.
The cleaning device 6 removes and collects toner remaining on the photosensitive drum 1 without being transferred onto the intermediate transfer belt 12. The cleaning device 6 includes a cleaning blade 61 that is in contact with the photosensitive drum 1 and scrapes off the residue on the photosensitive drum 1, and a recovery member 62 that recovers the residue scraped off by the cleaning blade 61. .

  The lubricant applying mechanism 7 is installed on the downstream side of the cleaning device 6 in the rotation direction A of the photosensitive drum 1, and applies a lubricant to the surface of the photosensitive drum 1. The lubricant application mechanism 7 includes an application brush 71 (lubricant supply member), a solid lubricant 72, a pressing member 73, and a leveling blade 74.

The coating brush 71 has a rotation axis parallel to the rotation axis of the photoconductor drum 1, and is installed so as to contact both the solid lubricant 72 and the photoconductor drum 1. In this state, the coating brush 71 rotates in the C direction shown in FIG. 4 to supply the lubricant scraped from the solid lubricant 72 to the photosensitive drum 1. At that time, the contact pressure also plays a role of spreading and applying the lubricant onto the photosensitive drum 1. The coating brush 71 is rotationally driven by a brush motor 75 (see FIG. 2).
Although the coating brush 71 rotates in the C direction here, the coating brush 71 may rotate in the direction opposite to the C direction depending on the system.

  The application brush 71 has, for example, brush bristles made of straight acrylic fibers on the outer circumference of the cored bar. The application brush 71 rotates while the tips of the brush bristles contact the surface of the photosensitive drum 1, and applies the lubricant attached to the brush bristles to the surface of the photosensitive drum 1.

  As the coating brush 71, for example, a brush made of one type of fiber, a brush made of two types of fibers, a brush woven of fibers having different thicknesses, or the like can be used. In addition to the application brush 71, a foaming roller can be used as the lubricant supply member, and the invention is not limited to these examples.

  The solid lubricant 72 is formed in a rectangular parallelepiped shape extending in the rotation axis direction of the photoconductor drum 1 and the rotation axis direction of the coating brush 71, and is used for the purpose of further improving the cleaning property and the transfer property. The solid lubricant 72 is configured so that the torque of the coating brush 71 varies under a predetermined condition (reference rotation speed) depending on the amount of the solid lubricant 72 used. The reference rotation speed is a rotation speed that is predetermined as a rotation speed when the torque of the application brush 71 (current value of the brush motor 75) is detected.

Examples of the material of the solid lubricant 72 include zinc stearate, salts of zinc, aluminum, copper, magnesium, calcium, etc., zinc oleate, salts of manganese, iron, copper, magnesium, etc., zinc palmitate, copper, Examples thereof include (higher) fatty acid metal salt particles such as salts of magnesium and calcium, zinc of linoleic acid, salts of calcium and the like, salts of zinc of ricinoleic acid, calcium and the like. As the lubricant, at least fatty acid metal salt particles having a volume-based median diameter in the range of 0.5 to 1.5 μm are used. The volume-based median diameter (volume average particle diameter) of the fatty acid metal salt particles (lubricant) can be measured using a laser diffraction particle size analyzer SALD-2100.
The above-mentioned various (higher) fatty acid metal salts (particles) can be used as the volume-based median-diameter fatty acid metal salt (particles), and among them, stearic acid metal salts are preferable, and examples thereof include calcium stearate and stearin. Magnesium acid, zinc stearate and the like are available, but zinc stearate is particularly preferable from the viewpoint of performance as a lubricant and electrostatic toner retention.

The pressure member 73 is composed of a spring or the like, and presses the solid lubricant 72 against the coating brush 71.
The leveling blade 74 is installed on the downstream side of the coating brush 71 in the rotation direction A of the photosensitive drum 1. The leveling blade 74 has a function of spreading and applying the lubricant supplied onto the photosensitive drum 1 by the coating brush 71 onto the photosensitive drum 1 and removing excess lubricant particles.

The secondary transfer roller 13 shown in FIG. 1 transfers (secondarily transfers) the toner images of a plurality of colors that have been transferred onto the intermediate transfer belt 12 from the primary transfer rollers 5 of the respective colors and are superimposed.
The fixing device 14 heats and pressurizes the toner image transferred onto the recording medium to perform a fixing process.

  The control unit 20 is configured to include a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The CPU expands various programs stored in the ROM into the RAM and expands the programs. The operation of each unit of the image forming apparatus 100 is comprehensively controlled in cooperation with the various programs executed. For example, the control unit 20 inputs an electric signal from the image reading unit 22 to perform various image processes, and outputs the image data Dy, Dm, Dc, and Dk of each color of YMCK generated by the image processing to the image forming unit 10. To do. The control unit 20 also controls the operation of the image forming unit 10 to form an image on the recording medium.

  The paper feed unit 21 is configured to include a plurality of paper feed trays, and each of the paper feed trays accommodates a plurality of different types of recording media. The paper feeding unit 21 supplies the recording medium accommodated by a predetermined transport path to the image forming unit 10.

  The image reading unit 22 includes an optical system such as a light source and a reflecting mirror. The image reading unit 22 irradiates the light source to the document conveyed by the automatic document conveying unit or the document placed on the platen glass, receives the reflected light, converts the received reflected light into an electric signal, and controls the control unit 20. Output to.

The display unit 23 is composed of an LCD (Liquid Crystal Display), and displays various operation screens, operating states of respective functions, and the like according to a display control signal input from the control unit 20.
The operation unit 24 receives various input operations by the user and outputs operation signals to the control unit 20. As the operation unit 24, various operation keys such as a numeric keypad and a start key, a touch panel integrally formed with the display unit 23, or the like can be used.

  The storage unit 25 includes an HDD (Hard Disk Drive), a semiconductor memory, and the like, and stores data such as program data and various setting data.

<Lubricant supply control processing>
The control unit 20 controls the amount of lubricant on the photosensitive drum 1. Specifically, the control unit 20 controls the brush motor 75 to adjust the number of rotations of the application brush 71, thereby controlling the amount of the lubricant on the photosensitive drum 1.

In the white area where the toner does not deposit on the photoconductor drum 1, if the amount of lubricant on the photoconductor drum 1 is small, the torque of the photoconductor drum 1 (hereinafter, referred to as photoconductor torque) increases, and the amount of lubricant is not less than an appropriate amount. Then, the photosensitive member torque becomes stable.
On the other hand, in the solid portion where 100% of toner is placed on the photoconductor drum 1, the photoconductor torque gradually increases as the amount of lubricant on the photoconductor drum 1 increases.
When the amount of lubricant on the photoconductor drum 1 becomes an appropriate amount or more, the photoconductor torques in the solid portion and the white background portion become substantially equal. Utilizing this, the lubricant on the photosensitive drum 1 is controlled.

First, the control unit 20 forms a white background on the photoconductor drum 1 and changes the rotation speed of the coating brush 71 stepwise or continuously to measure the photoconductor torque. Next, the control unit 20 causes a solid portion to be formed on the photoconductor drum 1 and changes the rotation speed of the coating brush 71 stepwise or continuously to measure the photoconductor torque. The minimum rotation speed of the coating brush 71 at which the photoconductor torques of the white background portion and the solid portion are substantially equal to each other is defined as the rotation speed during image formation (rotation speed for making the lubricant on the photoconductor drum 1 a proper amount). To do.
Before the white background portion is formed on the photosensitive drum 1, the solid portion may be formed and the photosensitive drum 1 may be refreshed. Moreover, when changing the rotation speed of the coating brush 71, it may be changed from a larger one to a smaller one or from a smaller one to a larger one.

  The control unit 20 controls the amount of the lubricant on the photoconductor drum 1 by adjusting the lubricant supplied to the photoconductor drum 1. As an appropriate amount of the lubricant on the photoconductor drum 1, for example, the supply amount of the lubricant with respect to the travel distance of the photoconductor is set to 50 to 300 mg / km.

  Alternatively, the control unit 20 controls the amount of the lubricant on the photoconductor drum 1 by adjusting the thickness of the lubricant on the photoconductor drum 1. For example, the thickness of the lubricant on the photosensitive drum 1 is measured by ESCA (Electron Spectroscopy for Chemical Analysis) or the like, and the appropriate amount of the lubricant is set to 2 to 10 nm. Further, the amount of the lubricant on the photosensitive drum 1 may be controlled by using a contact angle or a coefficient of friction as a substitute value of the thickness of the lubricant.

<Lubricant amount detection processing>
The control unit 20 detects a value that changes according to a torque fluctuation of the application brush 71 under a predetermined condition. That is, the control unit 20 functions as a detection unit. Specifically, the control unit 20 detects the torque of the application brush 71, which is obtained from the current value of the brush motor 75 when the application brush 71 is rotated at the reference rotation speed. The correspondence relationship between the current value of the brush motor 75 and the torque of the coating brush 71 when rotated at the reference rotation speed is stored in the storage unit 25 in advance.

The control unit 20 calculates the usage amount or the remaining amount of the solid lubricant 72 from the value (torque of the coating brush 71) detected under the predetermined condition, and notifies the usage amount or the remaining amount of the solid lubricant 72. That is, the control unit 20 functions as a notification unit. The correspondence relationship between the torque of the coating brush 71 and the usage amount or remaining amount of the solid lubricant 72 is stored in the storage unit 25 in advance.
The correspondence relationship between the current value of the brush motor 75 under a predetermined condition and the usage amount or remaining amount of the solid lubricant 72 may be stored in the storage unit 25 in advance.

(Specific example 1)
Here, a specific example 1 (solid lubricant 721) of the solid lubricant 72 will be described.
FIGS. 5A to 5D sequentially show how the solid lubricant 721 is scraped off by the coating brush 71. 5A to 5D show cross sections of the solid lubricant 721 orthogonal to the extending direction of the solid lubricant 721. The solid lubricant 721 is composed of two types of lubricant layers having different hardness along a direction (X direction) in which the solid lubricant 721 is scraped off by the application brush 71 and becomes smaller. In the initial state, the solid lubricant 721 has a first lubricant layer 721A closer to the application brush 71 (first consumed) and a second lubricant layer 721A farther from the application brush 71 (first consumed). Two lubricant layers 721B are included. The first lubricant layer 721A has a lower hardness (softer) than the second lubricant layer 721B. As a hardness measuring method, for example, a pencil hardness test is used.

  When the solid lubricant 721 is used, the lubricant is gradually scraped off by the coating brush 71 from the side of the solid lubricant 721 that is in contact with the coating brush 71, and the size of the solid lubricant 721 itself becomes small. To go. First, of the solid lubricant 721, the lubricant is gradually scraped off from the surface of the first lubricant layer 721A that is in contact with the coating brush 71, and when the first lubricant layer 721A disappears, the coating brush is removed. 71 comes into contact with the second lubricant layer 721B. After that, the lubricant is gradually scraped off from the second lubricant layer 721B by the application brush 71, and the second lubricant layer 721B disappears.

FIG. 6 is a graph showing the torque fluctuation (measured at the standard rotation speed) of the coating brush 71 with respect to the number of image formed sheets when the solid lubricant 721 is used. Data in which the torque of the coating brush 71 is associated with the number of image formations (or the usage amount, the remaining amount) is stored in the storage unit 25. As shown in FIG. 6, when the use of the solid lubricant 721 is started and the first lubricant layer 721A having low hardness is scraped off (FIGS. 5A and 5B), the coating brush 71 The torque is relatively small. As the use of the solid lubricant 721 progresses (FIGS. 5C and 5D) and the second lubricant layer 721B is scraped off, the torque of the coating brush 71 becomes relatively large.
Although the solid lubricant 721 is composed of two types of lubricant layers having different hardnesses, the solid lubricant 721 is composed of three or more types of lubricant layers having different hardnesses. Good. Further, it may be configured such that two types of lubricant layers having different hardnesses are alternately laminated.

  FIG. 7 is a graph showing the torque fluctuation (measured at the standard rotation speed) of the coating brush 71 with respect to the number of image formed sheets when the solid lubricant 72 composed of one type of lubricant is used (comparative example). In this case, the torque of the coating brush 71 hardly changes with respect to the number of formed images.

(Specific example 2)
Next, a specific example 2 (solid lubricant 722) of the solid lubricant 72 will be described.
FIGS. 8A to 8D sequentially show how the solid lubricant 722 is scraped off by the coating brush 71. 8A to 8D show cross sections of the solid lubricant 722 orthogonal to the extending direction of the solid lubricant 722. The solid lubricant 722 is composed of two types of lubricant layers having different hardness along a direction (X direction) in which the solid lubricant 722 is scraped off by the application brush 71 and becomes smaller. In the initial state, the solid lubricant 722 has a first lubricant layer 722A closer to the application brush 71 (first consumed) and a second lubricant layer 722A farther from the application brush 71 (first consumed). Two lubricant layers 722B. The first lubricant layer 722A has higher hardness (harder) than the second lubricant layer 722B.

  When the solid lubricant 722 is used, first, the lubricant is gradually scraped off from the surface of the solid lubricant 722 which is in contact with the coating brush 71 of the first lubricant layer 722A. When the second lubricant layer 722A disappears, the application brush 71 comes into contact with the second lubricant layer 722B. After that, the lubricant is gradually scraped off from the second lubricant layer 722B by the coating brush 71, and the second lubricant layer 722B disappears.

  FIG. 9 is a graph showing the torque fluctuation (measured at the standard rotation speed) of the coating brush 71 with respect to the number of image formations when the solid lubricant 722 is used. As shown in FIG. 9, when the use of the solid lubricant 722 is started and the first lubricant layer 722A having high hardness is scraped off (FIGS. 8A and 8B), the coating brush 71 of the coating brush 71 is removed. The torque is relatively large. When the use of the solid lubricant 722 progresses (FIGS. 8C and 8D) and the second lubricant layer 722B is scraped off, the torque of the coating brush 71 becomes relatively small.

(Specific example 3)
Next, a specific example 3 (solid lubricant 723) of the solid lubricant 72 will be described.
10A to 10D sequentially show how the solid lubricant 723 is scraped off by the coating brush 71. 10A to 10D show cross sections of the solid lubricant 723 orthogonal to the extending direction of the solid lubricant 723.

The solid lubricant 723 is configured such that the contact area with the application brush 71 changes along the direction (X direction) in which the solid lubricant 723 is scraped off by the application brush 71.
A direction in which the solid lubricant 723 is scraped off by the application brush 71 in a cross section of the solid lubricant 723 which is orthogonal to the extending direction of the solid lubricant 723 at a part or all of the extending direction of the solid lubricant 723. Along the (X direction), the width of the solid lubricant 723 in the Y direction orthogonal to the X direction is different.

The solid lubricant 723 has a space 80 (notch) formed at a part or all of the position in the extending direction of the solid lubricant 723. A straight line is extended from the wall surface 81 having the space 80 in the direction opposite to the X direction, and a point intersecting with the outer periphery of the coating brush 71 is defined as P1. A tangent line to the outer periphery of the coating brush 71 at a point P1 is 82, and an angle between the tangent line 82 and the X direction is α.
Of the surfaces forming the space portion 80, the surface first scraped by the coating brush 71 is 83. The angle formed by the surface 83 and the wall surface 81 having the space 80 is β.
In the solid lubricant 723, it is preferable to form the space 80 so that β <α. With such a configuration, when the coating brush 71 rushes into the space 80 of the solid lubricant 723, the surface 83 is scraped from the wall surface 81 side (FIG. 10B).

  FIG. 11 is a graph showing the torque fluctuation (measured at the standard rotation speed) of the coating brush 71 with respect to the number of image formations when the solid lubricant 723 is used. As shown in FIG. 11, before the use of the solid lubricant 723 is started and before the coating brush 71 reaches the space 80 (FIG. 10A), the torque of the coating brush 71 is relatively large. When the use of the solid lubricant 723 progresses and the coating brush 71 plunges into the space 80 (FIGS. 10B and 10C), the contact area between the coating brush 71 and the solid lubricant 723 becomes small, and the coating brush 71 The torque becomes relatively small. When the use of the solid lubricant 723 further progresses and the application brush 71 reaches the bottom surface 84 of the space portion 80 (FIG. 10D), the contact area between the application brush 71 and the solid lubricant 723 increases, and the application brush 71 has a larger contact area. The torque increases again.

  As shown in FIGS. 12A to 12C, when the solid lubricant 724 such that β> α is used, when the solid lubricant 724 is gradually scraped off, the coating brush 71 becomes solid. When the lubricant 724 enters the space 80, the surface 83 is scraped from the side (inner side) opposite to the wall surface 81. Then, as shown in FIG. 12C, the lubricant is not taken into the application brush 71, and the lubricant fragment 85 falls off, which causes a problem that the inside of the machine is contaminated. In addition, also in FIGS. 12A to 12C, regarding the space portion 80, the wall surface 81, the point P1, the tangent line 82, the surface 83, the angle α, and the angle β, the solid portions illustrated in FIGS. The same symbols as those defined for the lubricant 723 are used.

Next, the operation of the image forming apparatus 100 will be described.
FIG. 13 is a flowchart showing the image forming process executed by the image forming apparatus 100.

  First, in the image forming apparatus 100, when the power is turned on, the control unit 20 performs a stabilization process (step S1). The stabilization process is a process of setting various processes for forming an image.

  Next, the control unit 20 determines whether or not there is a lubricant amount detection request (step S2). Specifically, the control unit 20 determines whether or not the lubricant amount detection process is set. At this time, the control unit 20 determines whether or not a predetermined time has elapsed from the previous lubricant amount detection processing, and when the predetermined time has elapsed from the previous lubricant amount detection processing, the lubricant amount Judge that there is a detection request. The control unit 20 also determines whether or not a predetermined number of images have been formed from the previous lubricant amount detection processing, and if the predetermined number of images have been formed from the previous lubricant amount detection processing, the lubricant It may be determined that there is a quantity detection request.

  When there is a lubricant amount detection request (step S2; YES), the control unit 20 executes a lubricant amount detection process (step S3). In the lubricant amount detection process, the amount of use of the solid lubricant 72 and the like are calculated by detecting the torque of the coating brush 71 obtained from the current value of the brush motor 75 when the coating brush 71 is rotated at the reference rotation speed. It is a process to do. That is, the image forming apparatus 100 is provided with a mode for detecting a value that changes depending on the torque fluctuation of the coating brush 71 under a predetermined condition. The lubricant amount detection processing will be described later.

  After step S3 or when there is no lubricant amount detection request in step S2 (step S2; NO), the control unit 20 controls the image forming unit 10 to start image formation (step S4). ).

  Next, the control unit 20 determines whether or not there is a stabilization request (step S5). Specifically, the control unit 20 determines whether or not a predetermined time has elapsed since the last stabilization process, and if the predetermined time has elapsed since the last stabilization process, there is a stabilization request. To judge. Further, the control unit 20 determines whether or not a predetermined number of images have been formed since the last stabilization process, and if the predetermined number of images has been formed since the last stabilization process, there is a stabilization request. It may be judged.

When there is a stabilization request (step S5; YES), the control unit 20 executes stabilization processing (step S6).
After step S6, or when there is no stabilization request in step S5 (step S5; NO), the control unit 20 determines whether the image formation is completed (step S7).
When the image formation is not completed (step S7; NO), the process returns to step S5 and the process is repeated.

  When the image formation is completed in step S7 (step S7; YES), the control unit 20 determines whether or not there is a lubricant amount detection request (step S8). The details of the processing in step S8 are the same as in step S2.

  When there is a lubricant amount detection request (step S8; YES), the control unit 20 executes a lubricant amount detection process (step S9).

After step S9, or if there is no lubricant amount detection request in step S8 (step S8; NO), the image forming process ends.
Here, the lubricant amount detection process is executed before the image formation is started and after the image formation is completed. However, the lubricant amount detection process may be executed at the end of the job, and the number of image formation sheets is integrated. Therefore, the lubricant amount detection process may be executed when the number exceeds a certain number.

Next, the lubricant amount detection processing (steps S3 and S9) will be described with reference to FIG.
First, the control unit 20 controls the brush motor 75 to set the rotation speed of the coating brush 71 to the reference rotation speed (step S11).

  Next, the control unit 20 sets various process settings for the image forming unit 10 (step S12). For example, the control unit 20 sets the potential of the photosensitive drum 1, the potential of the developing sleeve 41 of the developing device 4, the potential of the primary transfer roller 5, and the like.

  Next, the control unit 20 activates the lubricant amount detection process (step S13). Specifically, the control unit 20 controls the brush motor 75 to rotate the coating brush 71 at the reference rotation speed and also rotate the photosensitive drum 1 and the like.

Next, the control unit 20 acquires the current value of the brush motor 75 for rotating the application brush 71 while the rotation speed of the application brush 71 is the reference rotation speed (step S14).
In order to detect the torque of the coating brush 71 with high accuracy, a solid image is formed on the photosensitive drum 1 as a pre-process before the current value of the brush motor 75 is acquired, and the surface state of the photosensitive drum 1 is refreshed. May be. When acquiring the current value of the brush motor 75, a solid image is formed on the photosensitive drum 1.
Further, the current value of the brush motor 75 may be acquired in a state where the white background portion is formed on the photosensitive drum 1. However, whether the current value of the brush motor 75 is acquired from the solid image or the current value of the brush motor 75 is acquired from the white background is the same condition every time.

  Next, the control unit 20 ends the lubricant amount detection process (step S15). Specifically, the control unit 20 stops the operation of the coating brush 71, the photosensitive drum 1, and the like.

  Next, the control unit 20 converts the current value of the brush motor 75 into the torque of the coating brush 71 (step S16). The control unit 20 detects the torque of the coating brush 71 by using the correspondence relationship between the current value of the brush motor 75 and the torque of the coating brush 71 stored in the storage unit 25.

  Next, the control unit 20 calculates the usage amount and the remaining amount of the solid lubricant 72 from the fluctuation of the torque of the coating brush 71 (step S17). At this time, the control unit 20 uses the correspondence relationship between the torque of the coating brush 71 and the usage amount or the remaining amount of the solid lubricant 72 stored in the storage unit 25. When the measured value (torque of the application brush 71) deviates from the average torque fluctuation, the correction value is corrected so as to match the current torque fluctuation, and the usage amount and the remaining amount of the solid lubricant 72 that are closer to the actual value are calculated. Ask. At this time, the usage amount and the remaining amount of the solid lubricant 72 may be corrected based on the information such as the temperature and the humidity.

  FIG. 15 shows an example of the average fluctuation of the torque of the coating brush 71 and the measured value (value converted from the current value) with respect to the number of formed images. The average fluctuation is an average value that is obtained in advance. Regarding the average fluctuation, the horizontal axis also shows the remaining amount (%) of the solid lubricant 72. Looking at the fluctuation of the measured value of the torque of the coating brush 71, the measured value 110 has just begun to decrease after the torque of the coating brush 71 has increased. Since the measured value 110 corresponds to the value 111 in the figure in the average variation, the remaining amount of the solid lubricant 72 when the measured value 110 is measured is predicted to be about 70%.

  FIG. 16 shows another example of the average fluctuation of the torque of the coating brush 71 with respect to the number of formed images and the measured value (value converted from the current value). Also in FIG. 16, with respect to the average variation, the horizontal axis also shows the remaining amount (%) of the solid lubricant 72. Looking at the variation in the measured value of the torque of the coating brush 71, the measured value 120 is almost constant as the torque of the coating brush 71 gradually decreases. Since the measured value 120 corresponds to the value 121 in the figure in the average variation, the residual amount of the solid lubricant 72 when the measured value 120 is measured is estimated to be about 60%.

Next, the control unit 20 notifies the usage amount and the remaining amount of the solid lubricant 72 (step S18). Specifically, the control unit 20 causes the display unit 23 to display the usage amount and the remaining amount of the solid lubricant 72. The control unit 20 may display only one of the usage amount of the solid lubricant 72 and the remaining amount of the solid lubricant 72.
With the above, the lubricant amount detection processing is completed.

Further, the control unit 20 may notify a warning such as urging replacement of the solid lubricant 72 when the remaining amount of the solid lubricant 72 becomes equal to or less than a predetermined value.
Further, the control unit 20 predicts the replacement time of the solid lubricant 72 (the time when the solid lubricant 72 disappears) when the image forming apparatus 100 is used at the current pace, from the usage amount or the remaining amount of the solid lubricant 72. However, it may be notified.

  As described above, according to the first embodiment, the solid lubricant 72 is configured so that the torque of the application brush 71 varies under a predetermined condition depending on the amount of the solid lubricant 72 used. By detecting the value that changes depending on the torque fluctuation of the coating brush 71, the usage amount of the solid lubricant 72 and the replacement time can be predicted.

  For example, when the solid lubricant 72 is composed of a plurality of lubricant layers having different hardnesses along a direction in which the solid lubricant 72 is scraped off by the application brush 71 and becomes smaller, the solid lubricant 72 is brought into contact with the application brush 71. Since the torque of the coating brush 71 varies depending on the hardness of the lubricant layer, the usage amount and the remaining amount of the solid lubricant 72 can be calculated.

  Further, when the solid lubricant 72 is configured so that the contact area with the application brush 71 changes along the direction in which the solid lubricant 72 is scraped off by the application brush 71 and becomes smaller, the contact with the application brush 71 is made. Since the torque of the coating brush 71 varies depending on the area, the usage amount and the remaining amount of the solid lubricant 72 can be calculated.

  The current value of the brush motor 75 when the application brush 71 is rotated at the reference rotation speed is not converted into the torque of the application brush 71, and the brush motor 75 is rotated when the application brush 71 is rotated at the reference rotation speed. It is also possible to detect the current value and directly calculate the usage amount or residual amount of the solid lubricant 72 from the current value of the brush motor 75.

  Further, with respect to the current value of the brush motor 75 acquired in a short period of time or the torque of the coating brush 71 converted from the current value, the difference (differential value) from the value one time before is taken, and the inflection point (increase or decrease in value) It is also possible to accurately detect the changing point), calculate the usage amount or the remaining amount of the solid lubricant 72, and notify it.

[Second Embodiment]
Next, a second embodiment to which the present invention is applied will be described.
The image forming apparatus according to the second embodiment has the same configuration as the image forming apparatus 100 according to the first embodiment, and therefore, common portions are denoted by the same reference numerals and description thereof is omitted. The configuration and processing characteristic of the second embodiment will be described below.

In the storage unit 25, a value that changes depending on the torque fluctuation of the application brush 71 (lubricant supply member) under a predetermined condition is set as one of explanatory variables, and the usage amount or the remaining amount of the solid lubricant 72 is used as an objective variable to perform machine learning. Machine learning results are prepared in advance. Specifically, the number of image formations, coverage (printing ratio), temperature, humidity, torque of the coating brush 71 (the coating brush 71 converted from the current value of the brush motor 75 when the coating brush 71 is rotated at the reference rotation speed). Torque is used as an explanatory variable, and the amount of use or the remaining amount of the solid lubricant 72 is used as an objective variable for machine learning.
Instead of the torque of the application brush 71, the current value itself of the brush motor 75 when the application brush 71 is rotated at the reference rotation speed may be used.

The control unit 20 detects a value that changes according to a torque fluctuation of the application brush 71 under a predetermined condition. Specifically, the control unit 20 detects the current value of the brush motor 75 when the application brush 71 is rotated at the reference rotation speed, or the torque of the application brush 71 obtained from the current value.
The control unit 20 acquires the usage amount or the remaining amount of the solid lubricant 72 from the machine learning result based on the detected value (current value of the brush motor 75 or torque of the application brush 71), and the solid lubricant Predict 72 replacement time. That is, the control unit 20 functions as a prediction unit.

  FIG. 17 shows the fluctuation line (initial line) predicted at the beginning of image formation regarding the torque fluctuation of the coating brush 71 with respect to the number of images formed, and the measured value (the torque value converted from the current value) based on the machine learning result. ) Shows a fluctuation line (learning line) predicted from (). Further, for each fluctuation line, the horizontal axis also shows the remaining amount (%) of the solid lubricant 72.

  The control unit 20 determines the solid lubricant 72 at each measurement time from the value (current value of the brush motor 75 or torque of the coating brush 71) that changes depending on the number of images formed, coverage, temperature, humidity, and torque fluctuation of the coating brush 71. The remaining amount of is calculated and the future torque fluctuation of the coating brush 71 is predicted. Then, the control unit 20 predicts a time when the remaining amount of the solid lubricant 72 becomes a predetermined value or less as the replacement time of the solid lubricant 72, and displays the replacement time of the solid lubricant 72 on the display unit 23. ,Notice.

Here, in addition to the value that changes according to the torque fluctuation of the coating brush 71, four pieces of information (image forming number, coverage, temperature, humidity) are used as explanatory variables. Furthermore, past replacement history of the solid lubricant 72, The replacement history of parts around the photosensitive drum 1, such as the history of toner replacement and the history of replacement of the photosensitive drum 1, may be used.
Furthermore, the current value of the brush motor 75 or the difference (differential value) between the current value of the brush motor 75 obtained in a short period of time and the value of the torque of the application brush 71 converted from the current value obtained one time before is calculated as the current value of the brush motor 75 or the application brush 71. It may be used to predict the fluctuation of the torque.

As described above, according to the second embodiment, the solid lubricant 72 is configured so that the torque of the coating brush 71 varies according to the usage amount of the solid lubricant 72 under a predetermined condition. By detecting the value that changes depending on the torque fluctuation of the coating brush 71, the usage amount of the solid lubricant 72 and the replacement time can be predicted.
The machine learning result is used to acquire the usage amount or the remaining amount of the solid lubricant 72 based on the current value of the brush motor 75 or the torque of the coating brush 71, and predict the replacement time of the solid lubricant 72. be able to.

  The description in each of the above embodiments is an example of the image forming apparatus according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of each part constituting the device can be appropriately changed without departing from the spirit of the present invention.

  For example, in each of the above-described embodiments, the current value of the brush motor 75 or the torque of the application brush 71 has been described as an example of the value that changes due to the torque fluctuation of the application brush 71 (lubricant supply member), but the present invention is not limited thereto. Not done.

1 Photoconductor Drum 2 Charging Device 3 Exposure Device 4 Developing Device 5 Primary Transfer Roller 6 Cleaning Device 7 Lubricant Applying Mechanism 10 Image Forming Section 12 Intermediate Transfer Belt 13 Secondary Transfer Roller 20 Control Section 23 Display Section 25 Storage Section 71 Application Brush 72 Solid lubricant 73 Pressurizing member 75 Brush motor 100 Image forming apparatus 721 Solid lubricant 722 Solid lubricant 723 Solid lubricant

Claims (12)

A rotatable image carrier,
A solid lubricant extending in the rotation axis direction of the image carrier,
The image bearing member has a rotation axis parallel to the rotation axis of the image bearing member, and is rotated while being in contact with the solid lubricant and the image bearing member to remove the lubricant scraped from the solid lubricant agent. A lubricant supply member for supplying to the body,
A motor for rotating the lubricant supply member,
Control means for controlling the amount of lubricant on the image carrier,
An image forming apparatus comprising:
The solid lubricant is configured so that the torque of the lubricant supply member varies in predetermined conditions depending on the amount of the solid lubricant used,
An image forming apparatus including a detection unit that detects a value that changes due to a torque fluctuation of the lubricant supply member under the predetermined condition.   The image forming apparatus according to claim 1, wherein the solid lubricant is composed of a plurality of lubricant layers having different hardnesses along a direction in which the solid lubricant is scraped off by the lubricant supply member and becomes smaller.   The image formation according to claim 1, wherein the solid lubricant is configured so that a contact area with the lubricant supply member changes along a direction in which the solid lubricant is scraped off by the lubricant supply member and becomes smaller. apparatus.   The solid lubricant is reduced by being scraped off by the lubricant supply member in a cross section of the solid lubricant which is orthogonal to the extending direction at a part or all of the extending direction of the solid lubricant. The image forming apparatus according to claim 3, wherein the width of the solid lubricant that is orthogonal to the direction is different along the direction.   The image forming apparatus according to claim 1, wherein the detection unit detects a current value of the motor or a torque of the lubricant supply member obtained from the current value.   The image forming apparatus according to claim 1, wherein the control unit controls the amount of the lubricant on the image carrier by adjusting the lubricant supplied to the image carrier.   The image forming apparatus according to claim 1, wherein the control unit controls the amount of the lubricant on the image carrier by adjusting the thickness of the lubricant on the image carrier. apparatus.   The image forming apparatus according to claim 1, wherein the control unit controls the amount of the lubricant on the image carrier by adjusting the rotation speed of the lubricant supply member.   9. The notification unit for calculating the usage amount or the remaining amount of the solid lubricant from the value detected by the detection unit, and notifying the usage amount or the remaining amount of the solid lubricant. The image forming apparatus according to item 1. A value that changes due to torque fluctuation of the lubricant supply member under the predetermined condition is set as one of explanatory variables, and a machine learning result obtained by machine learning using the usage amount or the remaining amount of the solid lubricant as an objective variable is prepared in advance. Cage,
The predicting means for predicting the replacement time of the solid lubricant by acquiring the usage amount or the remaining amount of the solid lubricant from the machine learning result based on the value detected by the detecting means. The image forming apparatus according to claim 1.   The image forming apparatus according to any one of claims 1 to 10, wherein a mode is provided in which the detection unit detects a value that changes according to a torque fluctuation of the lubricant supply member under the predetermined condition. A solid lubricant that extends in the rotation axis direction of the lubricant supply member and is rotated by the lubricant supply member in a state of being in contact with the lubricant supply member, whereby the lubricant is scraped off,
A solid lubricant configured such that the torque of the lubricant supply member varies under a predetermined condition depending on the amount of the solid lubricant used.

Images