JP7445187B2 - Lubricant supply device, process cartridge, and image forming device - Google Patents

Description

The present invention relates to a lubricant supply device that supplies lubricant to the surface of an image bearing member such as a photoreceptor drum or an intermediate transfer belt, and a process cartridge and an image forming apparatus equipped with the same.

Conventionally, in image forming devices such as copying machines and printers, it has been used to reduce wear and tear of cleaning blades that come into contact with image carriers such as photoreceptor drums and intermediate transfer belts, and to reduce deterioration of image carriers, as well as to prevent cleaning failures over time. A technique is widely known in which a lubricant supply device is installed to supply lubricant to the surface of an image bearing member for the purpose of suppressing the occurrence of filming on the surface of the image bearing member (for example, Patent Document (See 1st prize).

In detail, the lubricant supply device includes a lubricant supply roller that slides into contact with the photoreceptor drum (image carrier) at a position downstream of the cleaning blade (cleaning device), a solid lubricant that slides into the lubricant supply roller, and a solid lubricant. The solid lubricant is composed of a holding member that holds the solid lubricant, a spring (biasing member) that biases the solid lubricant toward the lubricant supply roller, and the like.
Then, the lubricant is gradually scraped off from the solid lubricant by a lubricant supply roller rotating in a predetermined direction, and the lubricant scraped off by the lubricant supply roller is applied (supplied) to the surface of the photoreceptor drum.

On the other hand, Patent Document 1 discloses that a solid lubricant is brought into contact with the lubricant supply roller at a position corresponding to the downstream side in the rotational direction of the lubricant supply roller, with the aim of making the lubricant supply amount uniform over time. A technique for providing a non-contact part that does not touch the user is disclosed.

In the technology of Patent Document 1, as the solid lubricant is consumed, the portion of the solid lubricant (non-contact portion) corresponding to the downstream side of the rotational direction of the lubricant supply roller is not scraped, and the image carrier is gradually removed. (photoreceptor drum), there was a possibility that a problem would occur where that portion would eventually come into contact with the image carrier.
If a portion of the solid lubricant comes into direct contact with the image carrier over time, problems such as abnormal noise may occur.

The present invention was made in order to solve the above-mentioned problems, and provides a lubricant supply device, a process cartridge, and a process cartridge that are less prone to the problem of solid lubricant coming into direct contact with an image carrier over time. An object of the present invention is to provide an image forming apparatus.

The lubricant supply device in this invention is a lubricant supply device that supplies lubricant to the surface of an image carrier on which a toner image is carried, and rotates in a predetermined rotation direction about a rotation axis, and a lubricant supply roller in sliding contact with a carrier; a columnar solid lubricant in sliding contact with the lubricant supply roller; a biasing member that biases the solid lubricant in a biasing direction toward the lubricant supply roller; When the solid lubricant is new, the length in the biasing direction is longer than the roller diameter of the lubricant supply roller, and the solid lubricant is biased on a side surface corresponding to the downstream side in the rotational direction. A notch is formed over the entire area in the direction of the rotational axis, and the cross-sectional area is the same from the tip of the direction to the first position in the central part, and the cross-sectional area gradually increases from the first position to the second position in the central part. .

According to the present invention, it is possible to provide a lubricant supply device, a process cartridge, and an image forming apparatus that are unlikely to cause the problem that the solid lubricant comes into direct contact with the image carrier over time.

1 is an overall configuration diagram showing an image forming apparatus in an embodiment of the present invention. FIG. 2 is a configuration diagram showing an image forming section. (A) A diagram showing a main part of the lubricant supply device in which a solid lubricant in a new state is installed, and (B) a main part of the lubricant supply device in which the solid lubricant has progressed in consumption. As a comparative example, (A) a main part of a lubricant supply device in which a solid lubricant in a new state is installed, and (B) a main part of a lubricant supply device in which the solid lubricant has progressed in consumption. It is. FIG. 7 is a diagram illustrating a main part of a lubricant supply device in which a solid lubricant in a new state is installed as a modification example 1; Modification 2 shows (A) the main part of the lubricant supply device in which a solid lubricant in a new state is installed, and (B) the main part of the lubricant supply device in which the solid lubricant has progressed in consumption. It is a diagram. FIG. 7 is a diagram showing the main parts of a lubricant supply device in which a new solid lubricant is installed as a third modification. FIG. 7 is a diagram showing the main parts of a lubricant supply device in which a new solid lubricant is installed as a fourth modification.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and repeated explanations thereof will be simplified or omitted as appropriate.

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

In FIG. 1, 1 is a color copying machine as an image forming device, 3 is a document conveyance device that conveys a document to a document reading section 4, 4 is a document reading section that reads image information of the document, and 6 is a color copying machine based on input image information. A writing section (exposure section) that emits a laser beam, and 7 a paper feeding device in which sheets P such as paper are stored.
In addition, 10Y, 10M, 10C, and 10BK are process cartridges as image forming units corresponding to each color (yellow, magenta, cyan, and black), 17 is an intermediate transfer belt on which toner images of multiple colors are transferred in a layered manner, and 18 is an intermediate transfer belt. A secondary transfer roller that transfers the toner image formed on the intermediate transfer belt 17 onto the sheet P is shown.
Further, 20 is a fixing device for fixing the unfixed image on the sheet P, and 28 is a toner container for replenishing the toner of each color to the developing device of each process cartridge (image forming section) 10Y, 10M, 10C, and 10BK. show.

Each of the process cartridges 10Y, 10M, 10C, and 10BK (image forming section) includes a photosensitive drum 11 as an image carrier, a charging device 12, a developing device 13, a cleaning device 15, and a lubricant supply device 16, respectively. It is integrated (see Figure 2). Each of the process cartridges 10Y, 10M, 10C, and 10BK is replaced in the apparatus main body 1 when it reaches the end of its life.
Toner images of respective colors (yellow, magenta, cyan, and black) are formed on the photosensitive drums 11 (image carriers) in each of the process cartridges 10Y, 10M, 10C, and 10BK.

The operation of the image forming apparatus during normal color image formation will be described below.
First, the document is conveyed from the document table by the conveyance rollers of the document conveyance device 3 and placed on the contact glass of the document reading section 4 . Then, the image information of the document placed on the contact glass is optically read by the document reading section 4.
Then, the image information of each color of yellow, magenta, cyan, and black is transmitted to the writing section 6. Laser light L (exposure light) based on the image information of each color is emitted from the writing section 6 onto the photoreceptor drums 11 of the corresponding process cartridges 10Y, 10M, 10C, and 10BK, respectively.

On the other hand, each of the four photosensitive drums 11 is rotating clockwise in the figure. First, the surface of the photosensitive drum 11 is uniformly charged at a position facing the charging device 12 (charging roller) (this is a charging process). In this way, a charged potential is formed on the photoreceptor drum 11. Thereafter, the charged surface of the photosensitive drum 11 reaches the irradiation position of each laser beam L.
In the writing section 6, laser beams L corresponding to image signals are emitted from a light source in correspondence to each color. The laser beam is incident on the polygon mirror, reflected, and then transmitted through a plurality of lenses. After passing through the plurality of lenses, the laser light passes through different optical paths for each color component of yellow, magenta, cyan, and black (this is an exposure process).

Laser light corresponding to the yellow component is irradiated onto the surface of the photosensitive drum 11 of the first process cartridge 10Y from the left side of the paper. At this time, the yellow component laser light is scanned in the rotation axis direction (main scanning direction) of the photoreceptor drum 11 by a polygon mirror rotating at high speed. In this way, an electrostatic latent image corresponding to the yellow component is formed on the photosensitive drum 11 after being charged by the charging device 12.

Similarly, the cyan component laser light is irradiated onto the surface of the photosensitive drum 11 of the second process cartridge 10C from the left in the paper, and an electrostatic latent image of the cyan component is formed. The laser beam corresponding to the magenta component is irradiated onto the surface of the photoreceptor drum 11 of the third process cartridge 10M from the left in the paper, and an electrostatic latent image corresponding to the magenta component is formed. The black component laser light is irradiated onto the surface of the photoconductor drum 11 of the process cartridge 10BK that is fourth from the left in the paper (the most downstream side with respect to the running direction of the intermediate transfer belt 17), and the black component laser light is A latent image is formed.

Thereafter, the surface of the photosensitive drum 11 on which the electrostatic latent image of each color is formed reaches a position facing the developing device 13, respectively. Then, toner of each color is supplied onto the photoreceptor drum 11 from each developing device 13, and the latent image on the photoreceptor drum 11 is developed (this is a developing process).
Thereafter, the surfaces of the photoreceptor drums 11 after the development process reach positions facing the intermediate transfer belt 17, respectively. Here, a primary transfer roller 14 is installed at each opposing position so as to come into contact with the inner circumferential surface of the intermediate transfer belt 17. Then, at the position of the primary transfer roller 14, the toner images of each color formed on the photoreceptor drum 11 are sequentially transferred onto the intermediate transfer belt 17 in an overlapping manner (this is a primary transfer step).

After the primary transfer process, the surfaces of the photosensitive drums 11 each reach a position facing the cleaning device 15. Then, the cleaning device 15 collects the untransferred toner remaining on the photoreceptor drum 11 (this is a cleaning process).
Thereafter, the surface of the photoreceptor drum 11 sequentially passes through the lubricant supply device 16 and the static eliminator, and a series of image forming processes on the photoreceptor drum 11 are completed.

On the other hand, the surface of the intermediate transfer belt 17, onto which the images of each color have been superimposed and transferred on the photosensitive drum 11, travels in the direction of the arrow in the figure and reaches the position of the secondary transfer roller 18. Then, at the position of the secondary transfer roller 18, the full-color image on the intermediate transfer belt 17 is secondarily transferred onto the sheet P (this is a secondary transfer process).
Thereafter, the surface of the intermediate transfer belt 17 reaches the position of the intermediate transfer belt cleaning device. Then, the untransferred toner on the intermediate transfer belt 17 is collected by the intermediate transfer belt cleaning device, and a series of transfer processes on the intermediate transfer belt 17 is completed.

Here, the sheet P conveyed to the position of the secondary transfer roller 18 is conveyed from the paper feeder 7 via a conveyance guide, registration rollers 19, and the like.
Specifically, the sheet P is fed by the paper feed roller 8 from the paper feed device 7 that stores the sheet P. After passing through a conveyance guide, the sheet P is guided to the registration rollers 19 . The sheet P that has reached the registration rollers 19 is conveyed toward the secondary transfer roller 18 in synchronization with the toner image on the intermediate transfer belt 17 .

Thereafter, the sheet P on which the full-color image has been transferred is guided to the fixing device 20. In the fixing device 20, the color image is fixed onto the sheet P at the nip between the fixing roller and the pressure roller.
After the fixing process, the sheet P is discharged as an output image outside the apparatus main body 1 by the paper discharge roller 29, and then stacked on the paper discharge section 5, completing a series of image forming processes.

Next, referring to FIG. 2, the image forming section of the image forming apparatus will be described in detail.
Note that FIG. 2 is a configuration diagram showing a process cartridge 10BK as an image forming section for black color. The process cartridge 10BK for black and the process cartridges 10Y, 10M, and 10C for color are composed of almost the same components except for the color of toner used in the image forming process, so Illustrations and descriptions of the process cartridges 10Y, 10M, and 10C will be omitted as appropriate.

As shown in FIG. 2, the process cartridge 10BK includes a photoreceptor drum 11 as an image carrier, a charging device 12 (charging roller) that charges the photoreceptor drum 11, and a static image formed on the photoreceptor drum 11. A developing device 13 that develops an electrolatent image, a cleaning device 15 that collects untransferred toner on the photoreceptor drum 11, and a lubricant supply device 16 that supplies lubricant onto the photoreceptor drum 11 are integrated into the case. It is stored properly.

Here, the photoreceptor drum 11 as an image carrier is a negatively charged organic photoreceptor, and has a photosensitive layer and the like provided on a drum-shaped conductive support.
The photosensitive drum 11 includes a conductive support serving as a base layer, an undercoat layer serving as an insulating layer, a charge generating layer and a charge transporting layer serving as a photosensitive layer, and a protective layer (surface layer) laminated in this order.

The charging device 12 is a charging roller formed by coating the outer periphery of a conductive metal core with an elastic layer of medium resistance, and is disposed downstream of the lubricant supply device 16 in the rotational direction of the photoreceptor drum 11. A predetermined voltage is applied to the charging device 12 from the power supply section, thereby uniformly charging the surface of the opposing photoreceptor drum 11.

The developing device 13 mainly includes a developing roller 13a facing the photosensitive drum 11, a first conveying screw 13b1 facing the developing roller 13a, and a second conveying screw 13b2 facing the first conveying screw 13b1 via a partition member. and a doctor blade 13c facing the developing roller 13a. The developing roller 13a includes a magnet that is fixedly installed 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 13a (sleeve) by the magnet, and the developer is carried on the developing roller 13a.
A two-component developer consisting of carrier and toner is housed within the developing device 13 .

The cleaning device 15 is disposed upstream of the lubricant supply device 16 in the rotational direction of the photosensitive drum 11 . The cleaning device 15 includes a cleaning blade 15a that contacts the photosensitive drum 11, a conveying coil 15b that conveys the toner collected in the cleaning device 15 as waste toner toward a waste toner collection container, and the like. The cleaning blade 15a is made of a rubber material such as urethane rubber, and contacts the surface of the photoreceptor drum 11 at a predetermined angle and with a predetermined pressure. As a result, deposits such as untransferred toner on the photoreceptor drum 11 are mechanically scraped off and collected into the cleaning device 15. Here, the deposits that adhere to the photoreceptor drum 11 include, in addition to untransferred toner, paper dust generated from the sheet P (paper), discharge products generated on the photoreceptor drum 11 during discharge by the charging device 12, There are additives added to toner, etc.

The lubricant supply device 16 includes a solid lubricant 16b, a lubricant supply roller 16a that is in sliding contact with the photoreceptor drum 11 and the solid lubricant 16b, a holding member 16f that holds the solid lubricant 16b, and a holding member 16f that holds the solid lubricant 16b. A case 16g that is stored together with the holding member 16f, a compression spring 16c (pressing mechanism) as a biasing member that biases the solid lubricant 16b toward the lubricant supply roller 16a, and a photoconductor drum 11 by the lubricant supply roller 16a. It is comprised of a thinning blade 16d that thins the lubricant supplied above, and the like.
The lubricant supply device 16 configured in this manner supplies a thin layer of lubricant onto the photoreceptor drum 11 . Note that the configuration and operation of the lubricant supply device 16 will be explained in detail later.

Referring to FIG. 2, the above-described imaging process will be explained in more detail.
The developing roller 13a is rotating in the arrow direction (counterclockwise) in FIG. The developer in the developing device 13 is stirred and mixed together with the toner replenished from the toner container 28 by the rotation of the first conveyance screw 13b1 and the second conveyance screw 13b2, which are arranged with a partition member interposed therebetween. It circulates in the longitudinal direction (this is the direction perpendicular to the plane of the paper in FIG. 2).

The toner that has been frictionally charged and attracted to the carrier is carried on the developing roller 13a together with the carrier. The developer carried on the developing roller 13a then reaches the position of the doctor blade 13c. After the developer on the developing roller 13a is adjusted to an appropriate amount at the position of the doctor blade 13c, it reaches a position facing the photoreceptor drum 11 (which is a developing area).

Thereafter, in the development area, the toner in the developer adheres to the electrostatic latent image formed on the surface of the photoreceptor drum 11. Specifically, the toner is formed into a latent image by an electric field formed by a potential difference (development potential) between the latent image potential (exposure potential) of the image area irradiated with the laser beam L and the development bias applied to the development roller 13a. (a toner image is formed).

Thereafter, most of the toner attached to the photoreceptor drum 11 in the developing process is transferred onto the intermediate transfer belt 17. Then, the untransferred toner remaining on the photosensitive drum 11 is collected into the cleaning device 15 by the cleaning blade 15a.

Here, the toner replenishing device provided in the apparatus main body 1 includes a bottle-shaped toner container 28 configured to be freely replaceable, and a toner hopper section that holds and rotates the toner container 28 and replenishes new toner to the developing device 13. It consists of and. Furthermore, new toner (yellow, magenta, cyan, or black) is stored in the toner container 28. Furthermore, a spiral protrusion is formed on the inner peripheral surface of the toner container 28 (toner bottle).

The new toner in the toner container 28 is appropriately replenished into the developing device 13 from the toner supply port as the toner (existing toner) in the developing device 13 is consumed. Although not shown, the consumption of toner in the developing device 13 is indirectly controlled by a reflective photosensor facing the photosensitive drum 11 and a magnetic sensor installed below the second conveyance screw 13b2 of the developing device 13. target or direct detection.

Hereinafter, the configuration and operation of the lubricant supply device 16 in this embodiment will be explained in detail.
Referring to FIG. 2, the lubricant supply device 16 includes a lubricant supply roller 16a, a solid lubricant 16b, a compression spring 16c as a biasing member, a holding member 16f, a case 16g, a thinning blade 16d, etc. be done.
The lubricant supply device 16 is disposed downstream of the cleaning device 15 (cleaning blade 15a) in the rotation direction of the photoconductor drum 11 and upstream of the charging device 12 in the rotation direction of the photoconductor drum 11. ing. Further, the layer thinning blade 16d is disposed on the downstream side in the rotational direction of the photosensitive drum 11 with respect to the lubricant supply roller 16a.

The lubricant supply roller 16a is a roller member in which a foamed elastic layer made of foamed polyurethane is formed on a shaft portion (core metal) made of a metal material, and the foamed elastic layer is in contact with the surface of the photoreceptor drum 11. In this state, it is rotated in a predetermined rotation direction (clockwise in FIG. 2). As a result, lubricant is supplied from the solid lubricant 16b onto the photoreceptor drum 11 via the lubricant supply roller 16a.
Further, the lubricant supply roller 16a is arranged so as to be in sliding contact with the solid lubricant 16b and the photoreceptor drum 11, and as the lubricant supply roller 16a rotates, the lubricant is scraped off from the solid lubricant 16b. The lubricant is applied onto the photoreceptor drum 11.

The solid lubricant 16b comes into sliding contact with the lubricant supply roller 16a, and is formed into a columnar shape.
Specifically, the solid lubricant 16b is formed by containing an inorganic lubricant in fatty acid metal zinc. Moreover, as fatty acid metallic zinc, one containing at least zinc stearate is preferable. The inorganic lubricant is preferably at least one of talc, mica, and boron nitride.
Zinc stearate is a typical lamellar crystal powder. Lamellar crystals have a layered structure made of self-organized amphiphilic molecules, and when shearing force is applied, the crystals crack along the layers and become slippery. Therefore, the surface of the photoreceptor drum 11 can be made to have a low coefficient of friction. That is, the surface of the photoreceptor drum 11 can be effectively covered with a small amount of lubricant by the lamellar crystals that uniformly cover the surface of the photoreceptor drum 11 under shear force. Then, the surface of the photoreceptor drum 11 can be covered relatively evenly and well protected from electrical stress during the charging process.
Furthermore, by using an inorganic lubricant having a plate-like structure such as talc, mica, or boron nitride, toner and lubricant are less likely to slip through the cleaning device 15 (cleaning blade 15a), and the charging device 12 is It can be made less dirty.

The compression spring 16c as a biasing member biases the solid lubricant 16b in a biasing direction (in the direction of the black arrow in FIG. 3) toward the lubricant supply roller 16a.
Specifically, in order to eliminate uneven contact between the lubricant supply roller 16a and the solid lubricant 16b, a holding member 16f is attached to the rear end of the solid lubricant 16b (the rear end in the urging direction). A compression spring 16c (biasing member) is arranged to bias the solid lubricant 16b toward the lubricant supply roller 16a.

The holding member 16f holds the rear end portion (the rear end portion in the biasing direction) of the solid lubricant 16b away from the position where the lubricant supply roller 16a and the solid lubricant 16b contact. That is, the holding member 16f supports the solid lubricant 16b at the rear in the urging direction.
The case 16g accommodates the holding member 16f and the solid lubricant 16b so as to be slidable in the urging direction. Moreover, one end side of the compression spring 16c is connected to the inner wall surface of the case 16g (which is the opposing surface facing the holding member 16f). The other end of the compression spring 16c is connected to a holding member 16f. With this configuration, as the solid lubricant 16b wears out, the holding member 16f slides within the case 16g in a direction closer to the lubricant supply roller 16a due to the urging force of the compression spring 16c.

The thinning blade 16d is a plate-shaped member made of a rubber material such as urethane rubber, and is in contact with the surface of the photoreceptor drum 11 at a predetermined angle and with a predetermined pressure. The thinning blade 16d is disposed on the downstream side in the rotation direction of the photoreceptor drum 11 (downstream side in the running direction) with respect to the cleaning blade 14a. The lubricant supplied onto the photoreceptor drum 11 by the lubricant supply roller 16a is uniformly and appropriately thinned onto the photoreceptor drum 11 by the layer thinning blade 16d.
When the solid lubricant 16b is applied to the surface of the photoreceptor drum 11 via the lubricant supply roller 16a, powdered lubricant is applied to the surface of the photoreceptor drum 11, but in this state, the lubricity is low. Since the lubricant is not sufficiently exerted, the thinning blade 16d functions as a member that thins and makes the lubricant a uniform layer. The thinning blade 16d forms a film of the lubricant on the photoreceptor drum 11, and the lubricant fully exhibits its lubricity.

The characteristic configuration and operation of the lubricant supply device 16 in this embodiment will be described in detail below with reference to FIG. 3 and the like.
3 (and FIGS. 4 to 8, which will be described later), for the sake of simplicity, only a part of the lubricant supply device 16 is illustrated, and the orientation in the rotational direction with respect to the photoreceptor drum 11 is changed. There is.

As shown in FIG. 3(A), when the solid lubricant 16b in this embodiment is new, the length M in the urging direction is longer than the roller diameter R of the lubricant supply roller (M> R), a side surface 16b5 corresponding to the downstream side in the rotational direction, in which a notch 16b1 (small cross section) is formed in a part in the biasing direction.
Specifically, in this embodiment, the notch 16b1 of the solid lubricant 16b is a portion shown by a broken line from the tip in the urging direction (the upper end in FIG. 3A) to the center. Specifically, the solid lubricant 16b in this embodiment has a straight (triangular) cross section perpendicular to the rotational axis direction, with the downstream side surface 16b5 extending from the tip to the center of the solid lubricant having a quadrangular prism shape. It has a notch (shape). Therefore, when the notch 16b1 is viewed three-dimensionally, it becomes a right quadrangular pyramid-shaped notch. In other words, the cross section in which the notch 16b1 of the solid lubricant 16b is formed (a cross section perpendicular to the urging direction and a small cross section) extends from the tip to the center of the downstream side surface 16b5. The area is formed so that the area gradually increases proportionally.

The solid lubricant 16b thus formed is subjected to a force in the direction of the white arrow in FIG. 3 as the lubricant supply roller 16a rotates, and is shifted in the direction of the white arrow by the amount of play inside the case 16g. It comes into sliding contact with the lubricant supply roller 16a. As the solid lubricant 16b becomes worn out (scraped) over time, it eventually becomes in a state as shown in FIG. 3(B).

In this embodiment, the notch 16b is formed by performing secondary processing on the solid lubricant in the shape of a rectangular prism, but the notch 16b as shown in FIG. 3(A) is formed using a mold from the beginning. It is also possible to produce a formed solid lubricant 16b. In this specification, etc., a notch-shaped portion attached to a columnar solid lubricant is defined as a "notch", regardless of the manufacturing method.
In addition, in the specification of this application, etc., the "new state" of a solid lubricant refers to the state before the solid lubricant is used in a lubricant supply device, regardless of whether it is a recycled product, the manufacturing process, storage conditions, etc. It is defined as the state of

In this way, by providing the notch 16b1 in a part of the downstream side surface 16b5 of the solid lubricant 16b, the problem that the solid lubricant 16b comes into direct contact with the photoreceptor drum 11 over time is less likely to occur.
Specifically, even when the new solid lubricant 116b is columnar without notches, as in the lubricant supply device 116 as a comparative example shown in FIG. 4(A), the rotation of the lubricant supply roller 16a is As a result, a force is applied in the direction of the white arrow in FIG. 4, and the lubricant supply roller 16a comes into sliding contact with the lubricant supply roller 16a while being shifted in the direction of the white arrow by the amount of play within the case 16g. Therefore, in the solid lubricant 116b installed in the lubricant supply device 116 as a comparative example, a portion on the side surface 116b5 on the downstream side in the rotational direction is an area where the solid lubricant 116b does not come into contact with the lubricant supply roller 16a and is hardly scraped. It becomes. Therefore, as shown in FIG. 4(B), as the solid lubricant 116b is consumed, the portion that is not scraped (the portion surrounded by the broken line) gradually increases, and the photoreceptor drum 11 , and eventually that portion will come into contact with the photoreceptor drum 11. If a portion of the solid lubricant 116b comes into direct contact with the photosensitive drum 11 over time, problems such as abnormal noise may occur.
On the other hand, in the lubricant supply device 16 according to the present embodiment, a notch 16b1 (small cross section) having a small cross section is formed in the downstream side surface 16b5 of the solid lubricant 16b, so the lubricant supply roller 16a This makes it difficult to form areas that are not scraped without contacting the surface. Therefore, as shown in FIG. 3B, even if the solid lubricant 16b continues to wear out, the problem that a portion of the downstream side surface 16b5 comes into contact with the photoreceptor drum 11 is less likely to occur. Therefore, problems such as abnormal noise caused by a portion of the solid lubricant 16b coming into direct contact with the photoreceptor drum 11 over time are less likely to occur.

Here, with reference to FIG. 3(A), in this embodiment, from the end of the notch 16b1 on the center side to the holding member 16f (or the rear end of the solid lubricant 16b in the urging direction) The length N in the urging direction of the lubricant supply roller 16a is configured to be shorter than the roller diameter R of the lubricant supply roller 16a (N<R).
In the columnar solid lubricant 16b, a portion having a large cross section (a cross section perpendicular to the urging direction) (a portion in which the cutout 16b1 is not formed) is a portion that is connected to the lubricant supply roller 16a. When the lubricant supply roller 16a comes into contact with the lubricant supply roller 16a, there may be a portion that is not scraped, so if the length N of that portion in the biasing direction is long, that portion will eventually contact the photoreceptor drum 11 directly. You will come into contact with it. In order to prevent such a problem, the length N of the large cross-section portion in the urging direction is set shorter than the roller diameter R of the lubricant supply roller 16a. In other words, even if a portion of the downstream side surface 16b5 of the large cross-section portion is not shaved and becomes longer in the urging direction, the length will not exceed the roller diameter R at most and will not contact the photoreceptor drum 11. . Therefore, the effects of the present invention described above are further exhibited.

Here, in the present embodiment, when the solid lubricant 16b is worn out (scraped) and the part where the notch 16b1 is formed comes into contact with the lubricant supply roller 16a, it is perpendicular to the urging direction of that part. It is preferable that all of the cross-sections (small cross-sections) contact the lubricant supply roller 16a.
As a result, when the small cross-section portion of the solid lubricant 16b is in contact with the lubricant supply roller 16a, no area is formed on the downstream side surface 16b5, so that the solid lubricant 16b decreases over time. The problem that a part of the photosensitive drum 11 comes into direct contact with the photosensitive drum 11 is less likely to occur.

<Modification 1>
As shown in FIG. 5, in the lubricant supply device 16 according to the first modification, the shape of the notch 16b1 of the solid lubricant 16b in the new state is different from that of the present embodiment.
Specifically, the notch 16b1 (small cross section) of the solid lubricant 16b shown in FIG. The cross-sectional area gradually increases in a short region toward the end of the section.
Moreover, the notch 16b1 (small cross-sectional part) of the solid lubricant 16b shown in FIG. 5(B) is formed so that the cross-sectional area gradually increases in a quadratic curve from the tip to the center of the downstream side surface 16b5. has been done.
Further, as in the present embodiment, each of the solid lubricants 16b is set so that the length N of the large cross-section portion in the urging direction is shorter than the roller diameter R of the lubricant supply roller 16a. Yes (N<R).
Also in the modified example 1 configured in this way, similarly to the present embodiment, it is possible to prevent the problem that a part of the solid lubricant 16b comes into direct contact with the photoreceptor drum 11 over time. Can be done.

<Modification 2>
As shown in FIG. 6(A), the lubricant supply device 16 according to Modification Example 2 also differs from that of the present embodiment in the shape of the notch 16b1 of the solid lubricant 16b in a new state.
As shown in FIG. 6(A), the notch 16b1 of the solid lubricant 16b in a new state is a groove-shaped (substantially rectangular groove-shaped) cutout in the center portion in the urging direction.
Therefore, the solid lubricant 16b has a large cross section from the tip to the notch 16b1, a small cross section where the notch 16b1 is formed, and a large cross section from the notch 16b1 to the rear end (holding member 16f). It is a cross section.
The solid lubricant 16b configured in this manner is also subjected to force in the direction of the white arrow in FIG. 6(A) as the lubricant supply roller 16a rotates from when it is new as shown in FIG. It comes into sliding contact with the lubricant supply roller 16a while being shifted in the direction of the white arrow by an amount of play of 16g. Then, the downstream side surface 16b5 side of the solid lubricant 16b does not come into contact with the lubricant supply roller 16a and becomes an area that is hardly scraped. Then, as the solid lubricant 116b wears out, the unscraped portion gradually becomes longer and closer to the photoreceptor drum 11. However, as the solid lubricant 116b wears out further and the small cross-section portion in which the notch 16b1 is formed comes into sliding contact with the lubricant supply roller 16a, as shown in FIG. 16b2 is broken and falls into the case of the process cartridge 10BK. Therefore, as shown in FIG. 6(B), even if the solid lubricant 16b continues to wear out, the problem of a part of the downstream side surface 16b5 coming into contact with the photoreceptor drum 11 does not occur. Become.
Here, in modification 2, as shown in FIG. 6(A), the length N1 in the urging direction from the notch 16b1 to the holding member 16f (or the rear end of the solid lubricant 16b) is the lubricant It is set to be shorter than the roller diameter R of the supply roller 16a (N1<R). As a result, even if the solid lubricant 16b is further consumed from the state shown in FIG. 6(B), the problem that a part of the downstream side surface 16b5 comes into contact with the photoreceptor drum 11 does not occur.
Further, as shown in FIG. 6(A), the length N2 in the urging direction from the tip of the solid lubricant 16b in the urging direction to the notch 16b1 is shorter than the roller diameter R of the lubricant supply roller 16a. (N2<R). As a result, even if the solid lubricant 16b wears down from the new state shown in FIG.
Also in the second modified example configured as described above, similarly to the present embodiment, it is possible to prevent the problem that a part of the solid lubricant 16b comes into direct contact with the photoreceptor drum 11 over time. Can be done.

<Modification 3>
As shown in FIG. 7, the lubricant supply device 16 in Modification 3 is different from that in Modification 2 in the shape of a groove-like notch 16b1 formed in the new solid lubricant 16b.
Specifically, the notch 16b1 (small cross section) of the solid lubricant 16b shown in FIG. 7(A) is formed in a substantially wedge shape.
Moreover, the notch 16b1 (small cross section) of the solid lubricant 16b shown in FIG. 7(B) is formed in a substantially semi-elliptical shape.
In addition, in each of the solid lubricants 16b, the lengths N1 and N2 in the urging direction of the rear end side and the front end side with the notch 16b1 sandwiched therebetween are both the lubricant supply roller. It is set to be shorter than the roller diameter R of 16a (N1<R, N2<R).
Also in Modification 3 configured in this way, as in Modification 2, the problem that a part of the solid lubricant 16b side comes into direct contact with the photoreceptor drum 11 over time is less likely to occur. can do.

<Modification 4>
As shown in FIG. 8, the lubricant supply device 16 in Modification 4 is different from those in Modifications 2 and 3 in the number of groove-shaped notches 16b1 formed in the new solid lubricant 16b.
As shown in FIG. 8, the notches 16b1 of the solid lubricant 16b in a new state are a plurality of notches cut out at intervals in the urging direction. Specifically, two notches 16b1 are formed in the downstream side surface 16b5 of the solid lubricant 16b at intervals in the urging direction.
With the solid lubricant 16b configured in this way, even if the length M of the solid lubricant 16b in the urging direction is long, the solid lubricant 116b continues to wear out and the unscraped portion becomes longer. Even so, each time the small cross-section portion in which the notch 16b1 is formed reaches a position where it comes into sliding contact with the lubricant supply roller 16a, the portion that is not cut will be broken. Therefore, even if the solid lubricant 16b continues to wear out, the problem that a part of the downstream side surface 16b5 comes into contact with the photoreceptor drum 11 does not occur.
Here, in modification 4, as shown in FIG. 8, the urging direction from the rearmost notch 16b1 of the plurality of notches 16b1 to the holding member 16f (or the rear end of the solid lubricant 16b) The length N1 is set to be shorter than the roller diameter R of the lubricant supply roller 16a (N1<R). As a result, even after the solid lubricant 16b is consumed and only the area N1 remains, a portion of the downstream side surface 16b5 remains in contact with the photoreceptor drum 11. This means that no problems will occur.
Further, as shown in FIG. 8, the length N2 in the biasing direction from the tip of the solid lubricant 16b in the biasing direction to the most distal notch 16b1 of the plurality of notches 16b1 is It is set to be shorter than the roller diameter R of 16a (N2<R). As a result, even if the solid lubricant 16b wears down from the new state shown in FIG.
Further, as shown in FIG. 8, the length N3 in the urging direction between adjacent notches 16b1 of the plurality of notches 16b1 is set to be shorter than the roller diameter R of the lubricant supply roller 16a. is set (N3<R). As a result, even if the solid lubricant 16b is consumed between two adjacent notches 16b1, the portion that cannot be scraped falls off before it comes into contact with the photoreceptor drum 11.
In Modification 4 configured in this way, as in Modifications 2 and 3, the problem of a portion of the solid lubricant 16b coming into direct contact with the photoreceptor drum 11 over time is less likely to occur. can do.
In addition, in modification 4, two notches 16b1 are formed at separate positions in the biasing direction, but the number of notches 16b1 is not limited to this, and may be three or more.

As described above, the lubricant supply device 16 in this embodiment includes the lubricant supply roller 16a that rotates in a predetermined rotational direction and slides on the photoreceptor drum 11 (image carrier), and the lubricant supply roller 16a. A column-shaped solid lubricant 16b that slides in contact with the lubricant supply roller 16a and a compression spring 16c (biasing member) that biases the solid lubricant 16b in a biasing direction toward the lubricant supply roller 16a are provided. When the solid lubricant 16b is new, the length M in the urging direction is longer than the roller diameter R of the lubricant supply roller 16a, and the solid lubricant 16b is attached to the side surface 16b5 corresponding to the downstream side in the rotational direction. A notch 16b1 is formed in a portion in the force direction.
This makes it difficult for the solid lubricant 16b to come into direct contact with the photoreceptor drum 11 over time.

In this embodiment, each part of the image forming section (the photosensitive drum 11, the charging device 12, the developing device 13, the cleaning device 15, and the lubricant supply device 16) is integrated into the process cartridges 10Y, 10M, By configuring 10C and 10BK, the image forming section is made more compact and maintenance workability is improved.
On the other hand, each of the parts 11, 12, 13, 15, and 16 in the image forming part may not be used as a component of the process cartridge, but may be configured to be independently installed in the apparatus main body 1 in a replaceable manner. Even in such a case, the same effects as in this embodiment can be obtained.
In this application, the term "process cartridge" refers to a charging device that charges an image carrier, a developing device that develops a latent image formed on the image carrier, and a cleaning device that cleans the top of the image carrier. It is defined as a unit in which at least one of these and an image carrier are integrated and installed removably in the main body of an image forming apparatus.

Further, in this embodiment, the present invention is applied to the lubricant supply device 16 installed in the color image forming apparatus 1. On the other hand, the present invention can naturally be applied to a lubricant supply device installed in a monochrome image forming apparatus.
Further, in the present embodiment, the present invention is applied to the lubricant supply device 16 that supplies lubricant onto the photoreceptor drum 11 as an image carrier, but it is also possible to lubricate image carriers other than the photoreceptor drum 11. Naturally, the present invention can also be applied to a lubricant supply device (for example, a lubricant supply device that supplies lubricant to the intermediate transfer belt 17).
Further, in this embodiment, the present invention is applied to the lubricant supply device 16 installed downstream of the cleaning blade 15a (cleaning device 15), but the lubricant supply device is installed upstream of the cleaning blade 15a. Even if the lubricant supply device is installed, the present invention can be applied to the lubricant supply device.
Even in such cases, effects similar to those of this embodiment can be obtained.

Further, in this embodiment, a foamed elastic layer formed on a core metal is used as the lubricant supply roller 16a, but a straight or loop-shaped brush is used as the lubricant supply roller 16a on the outer periphery of the core metal. It is also possible to use one wrapped in hair. In that case, resin fibers such as polyester, nylon, rayon, acrylic, vinylon, and vinyl chloride can be used as the brush bristles, and if necessary, conductive fibers mixed with a conductivity imparting agent such as carbon can be used. can. Further, the brush bristles may have a length (hair length) of 0.2 to 20 mm and a brush density of 20,000 to 100,000 F/inch ² .
Further, in this embodiment, the compression spring 16c is used as the urging member that urges the solid lubricant 16b against the lubricant supply roller 16a, but the configuration of the urging member is not limited to this. Various forms can also be used.
Even in such cases, substantially the same effects as those of this embodiment can be obtained.

Note that it is clear that the present invention is not limited to this embodiment, and that this embodiment can be modified as appropriate within the scope of the technical idea of the present invention in addition to what is suggested in this embodiment. be. Further, the number, position, shape, etc. of the constituent members are not limited to those in this embodiment, and can be set to a suitable number, position, shape, etc. for implementing the present invention.

1 Image forming device (image forming device main body),
11 Photosensitive drum (image carrier),
16 Lubricant supply device,
16a lubricant supply roller,
16b solid lubricant,
16b1 notch,
16c compression spring (biasing member),
16f holding member,
16g case.

Japanese Patent Application Publication No. 2014-13317

Claims (9)

A lubricant supply device that supplies lubricant to the surface of an image carrier on which a toner image is carried,
a lubricant supply roller that rotates in a predetermined rotational direction about a rotation axis and slides into contact with the image carrier;
a columnar solid lubricant in sliding contact with the lubricant supply roller;
a biasing member that biases the solid lubricant in a biasing direction that approaches the lubricant supply roller;
Equipped with
When the solid lubricant is new, the length in the biasing direction is longer than the roller diameter of the lubricant supply roller, and the tip in the biasing direction is located on a side surface corresponding to the downstream side in the rotational direction. A notch is formed over the entire area in the direction of the rotation axis, the cross-sectional area being the same from the first position to the first position of the central part, and the cross-sectional area gradually increasing from the first position to the second position of the central part. lubricant supply device. comprising a holding member that holds a rear end portion of the solid lubricant in the urging direction away from a position where the lubricant supply roller and the solid lubricant contact,
The lubricant according to claim 1, wherein a length in the biasing direction from an end of the notch on the center side to the holding member is shorter than a roller diameter of the lubricant supply roller. agent supply device. A lubricant supply device that supplies lubricant to the surface of an image carrier on which a toner image is carried,
a lubricant supply roller that rotates in a predetermined rotational direction about a rotation axis and slides into contact with the image carrier;
a columnar, single-layer solid lubricant in sliding contact with the lubricant supply roller;
a biasing member that biases the solid lubricant in a biasing direction that approaches the lubricant supply roller;
a holding member that holds a rear end portion of the solid lubricant in the urging direction away from a position where the lubricant supply roller and the solid lubricant contact;
Equipped with
When the solid lubricant is in a new state, the length in the urging direction is longer than the roller diameter of the lubricant supply roller, and the solid lubricant has a length in the urging direction that is longer than the roller diameter of the lubricant supply roller, and the solid lubricant extends from the side surface corresponding to the downstream side in the rotational direction to the upstream side in the rotational direction. A lubricant supply device characterized in that a groove-shaped notch is formed in a central portion in the urging direction and over the entire area in the direction of the rotational axis, but does not reach the side surface corresponding to the lubricant supply device. a length from the notch to the holding member in the urging direction is shorter than a roller diameter of the lubricant supply roller;
The lubricant according to claim 3, wherein a length in the urging direction from a tip of the solid lubricant in the urging direction to the notch is shorter than a roller diameter of the lubricant supply roller. agent supply device. A lubricant supply device that supplies lubricant to the surface of an image carrier on which a toner image is carried,
a lubricant supply roller that rotates in a predetermined rotational direction about a rotation axis and slides into contact with the image carrier;
a columnar, single-layer solid lubricant in sliding contact with the lubricant supply roller;
a biasing member that biases the solid lubricant in a biasing direction that approaches the lubricant supply roller;
a holding member that holds a rear end portion of the solid lubricant in the urging direction away from a position where the lubricant supply roller and the solid lubricant contact;
Equipped with
When the solid lubricant is in a new state, the length in the urging direction is longer than the roller diameter of the lubricant supply roller, and the solid lubricant has a length in the urging direction that is longer than the roller diameter of the lubricant supply roller, and the solid lubricant extends from the side surface corresponding to the downstream side in the rotational direction to the upstream side in the rotational direction. A lubricant supply device characterized in that a plurality of groove-shaped notches are formed at intervals in the urging direction over the entire area in the direction of the rotation axis in a range that does not reach the side surface corresponding to the side surface . A length in the biasing direction from a rearmost notch of the plurality of notches to the holding member is shorter than a roller diameter of the lubricant supply roller,
The length in the biasing direction from the tip of the solid lubricant in the biasing direction to the most distal notch of the plurality of notches is shorter than the roller diameter of the lubricant supply roller,
The lubricant supply device according to claim 5, wherein lengths of adjacent notches of the plurality of notches in the biasing direction are shorter than a roller diameter of the lubricant supply roller. . The solid lubricant is characterized in that when wear progresses to the position of the groove-shaped notch, a portion of the solid lubricant that is not scraped by the lubricant supply roller without contacting the lubricant supply roller breaks. The lubricant supply device according to any one of claims 3 to 6. A process cartridge that is removably installed in an image forming apparatus main body,
A process cartridge comprising the lubricant supply device according to any one of claims 1 to 7 and the image carrier. An image forming apparatus comprising the lubricant supply device according to any one of claims 1 to 7 and the image carrier.

Images