JP2018017912A - Image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always apply a fixed amount of lubricant to an image carrier.SOLUTION: A lubricant application unit 220A includes guide members 230a, 230b and rail members 240a, 240b. The rail members 240a, 240b are erected on the side faces of a support member 226. The rail members 240a, 240b have a rail groove formed along their longitudinal direction. The rail groove is constructed so as to be gradually increased in width from its lower end toward the upper end. The guide members 230a, 230b are attached to each of both ends of the support member 226, and slidably engage the rail grooves of the rail members 240a, 240b. When the remaining amount of a lubricant 224 decreases and the guide members 230a, 230b rise along the rail members 240a, 240b, a backlash in the guide members 230a, 230b gradually increases, so that it is possible to increase the applied amount of the lubricant 224 to a photoreceptor drum 1 due to an increase in the vibration transmitted to the lubricant 224.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an image forming apparatus.

  In an electrophotographic image forming apparatus, for example, a blade cleaning system is employed as means for removing residual toner such as untransferred toner and transfer residual toner on an image carrier. In the cleaning device of the blade cleaning system, residual toner on the image carrier is removed by bringing a flat plate-like cleaning blade made of an elastic body into contact with the surface of the rotating image carrier.

  Incidentally, in recent years, in electrophotographic image forming apparatuses, there has been a demand for reducing the particle size of toner particles from the viewpoint of high image quality. As a method for obtaining such toner particles, for example, an emulsion polymerization method or a suspension polymerization method. Such polymerization methods are used. However, when the toner particles are reduced in size, the adhesion between the toner particles and the image carrier increases, which makes it difficult to remove the residual toner on the latent image carrier. In particular, when a so-called polymerized toner produced by a polymerization method is used, the shape of the toner particles becomes almost spherical, so that the toner particles roll on the image carrier and pass through the cleaning blade, thereby cleaning the toner particles. There is a problem that defects are likely to occur, and it is difficult to remove residual toner on the image carrier.

  Further, when toner that passes through the cleaning blade is generated, toner aggregates are formed on the latent image carrier with the toner as a core, and granular white spots (granular noise) are generated in the printing portion of the solid image. There is also.

  In order to deal with these quality problems, at present, a lubricant is supplied onto the image carrier, and cleaning is performed in a state where the adhesion between the toner particles and the latent image carrier is reduced. As a method of supplying the lubricant onto the image carrier, there is a lubricant coating method in which a brush is brought into contact with a lubricant having a predetermined shape, the lubricant is scraped off with the brush, and the peeled lubricant is supplied to the surface of the image carrier. . For example, Patent Document 1 describes a lubricant application mechanism that applies a lubricant onto an image carrier by pressing a lubricant against a rotating brush with a spring and scraping the lubricant with the brush.

JP 2010-210799 A

  However, the lubricant application mechanism described in Patent Document 1 has the following problems. In other words, since the lubricant is pressed against the brush by the spring, when the remaining amount of the lubricant decreases, the spring expands accordingly, and the pressing force (force) of the lubricant against the brush also decreases. As a result, the amount of lubricant applied to the image carrier is reduced, and it is difficult to remove the residual toner on the image carrier, resulting in a problem of image defects.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus that can always apply a certain amount of lubricant to an image carrier.

  An image forming apparatus according to the present invention includes an image carrier that carries a toner image, an application brush that is configured to rotate and scrapes off and applies a lubricant to the image carrier, and a pressure that presses the lubricant against the application brush. And a vibration control unit that controls vibration transmitted to the lubricant in accordance with a pressing force applied to the lubricant by the pressing member.

  According to the present invention, since the vibration transmitted to the lubricant is controlled by the vibration control unit in accordance with the pressing force on the lubricant by the pressing member, even when the pressing force of the pressing member is reduced due to the reduction of the lubricant, a certain amount of lubricant is applied. It can be applied to an image carrier.

1 is a diagram illustrating a configuration example of an image forming apparatus according to an embodiment of the present invention. It is a figure which shows an example of a structure of the lubricant application part which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the structural example of a guide member and a rail member (the 1). It is a perspective view which shows the structural example of a guide member and a rail member (the 2). It is a figure which shows the structural example of a rail groove | channel. It is a figure for demonstrating the operation example of a lubricant application part. An example of the relationship between the lubricant vibration amount and the total consumption amount of the lubricant when the vibration is linearly applied to the lubricant is shown. An example of the relationship between the amount of lubricant vibration and the total amount of lubricant consumed when vibration is applied to the lubricant stepwise is shown. It is a figure which shows an example of structures, such as a lubrication agent application part which concerns on 2nd Embodiment. It is a figure for demonstrating the operation example of a lubricant application part. It is a figure which shows an example of structures, such as a lubrication agent application part which concerns on the 3rd Embodiment of this invention. It is a figure for demonstrating the operation example of a lubricant application part. It is a figure which shows an example of structures, such as a lubrication agent application part which concerns on the 4th Embodiment of this invention. It is a figure for demonstrating the operation example of a lubricant application part.

  Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, the dimension ratio of drawing is expanded on account of description and may differ from an actual ratio.

<First Embodiment>
[Configuration Example of Image Forming Apparatus 100]
FIG. 1 shows an example of the configuration of an image forming apparatus 100 according to the present invention. As shown in FIG. 1, the image forming apparatus 100 is called a tandem type image forming apparatus, and includes an automatic document feeder 80 and an apparatus main body 102. The automatic document conveyance unit 80 is attached to the upper part of the apparatus main body 102 and sends out the paper set on the conveyance table to the image reading unit 90 of the apparatus main body 102 by a conveyance roller or the like.

  The apparatus main body 102 includes an operation display unit 70, an image reading unit 90, an image forming unit 10, an intermediate transfer belt 8, a paper feeding unit 20, a registration roller pair 32, a fixing unit 44, and automatic paper reverse conveyance. A unit 60 (Auto Duplex Unit: hereinafter referred to as ADU), a control unit 250 (see FIG. 2), a photoreceptor driving unit 260 (see FIG. 2), and a brush driving unit 270 (see FIG. 2) are included. . The control unit 250, the photoconductor driving unit 260, and the brush driving unit 270 will be described later for convenience.

  The operation display unit 70 includes a touch panel in which a display unit and an input unit are combined, and a plurality of operation keys including a start key and a determination key provided in a peripheral part of the touch panel. The operation display unit 70 displays an operation screen or the like on the screen, or receives information such as an image forming condition input by a touch operation on the operation screen or an operation of an operation key.

  The image reading unit 90 scans and exposes the document placed on the document table or the document transported by the automatic document transport unit 80 by the optical system of the scanning exposure device, and the image of the scanned document is CCD (Charge Coupled Device). ) Photoelectric conversion is performed by an image sensor to generate an image information signal. The image information signal is output to the image forming unit 10 after being subjected to analog processing, analog / digital (hereinafter referred to as A / D) conversion processing, pseudo correction, image compression processing, and the like by an image processing unit (not shown).

  The image forming unit 10 forms an image by electrophotography, and includes an image forming unit 10Y that forms a yellow (Y) image, an image forming unit 10M that forms a magenta (M) image, The image forming unit 10C forms a cyan (C) color image, and the image forming unit 10K forms a black (K) color image. In this example, common function names, for example, Y, M, C, and K indicating colors to be formed are added to the back of the reference numeral 10.

  The image forming unit 10Y includes a photosensitive drum 1Y, a charger 2Y, an exposure unit (optical writing unit) 3Y, a developing unit 4Y, and a cleaning unit 200Y arranged around the photosensitive drum 1Y. The image forming unit 10M includes a photosensitive drum 1M, a charger 2M, an exposure unit 3M, a developing unit 4M, and a cleaning unit 200M disposed around the photosensitive drum 1M. The image forming unit 10 </ b> C includes a photosensitive drum 1 </ b> C, a charger 2 </ b> C, an exposure unit 3 </ b> C, a developing unit 4 </ b> C, and a cleaning unit 200 disposed around the photosensitive drum 1 </ b> C. The image forming unit 10K includes a photosensitive drum 1K, a charger 2K, an exposure unit 3K, a developing unit 4K, and a cleaning unit 200K disposed around the photosensitive drum 1K.

  Respective photosensitive drums (image carriers) 1Y, 1M, 1C, and 1K in the image forming units 10Y, 10M, 10C, and 10K, chargers 2Y, 2M, 2C, and 2K, exposure units 3Y, 3M, 3C, and 3K, development The devices 4Y, 4M, 4C, and 4K, the cleaning units 200Y, 200M, 200C, and 200K, and the primary transfer rollers 7Y, 7M, 7C, and 7K have a common configuration. In the following description, Y, M, C, and K are not used unless particularly distinguished.

  The charger 2 charges the surface of the photosensitive drum 1 almost uniformly. The exposure unit 3 is composed of, for example, an LPH (LED Print Head) having an LED array and an imaging lens, or a polygon mirror type laser exposure scanning device, and the photosensitive drum 1 is irradiated with laser light based on an image information signal. Scan to form an electrostatic latent image. The developing device 4 develops the electrostatic latent image formed on the photosensitive drum 1 with toner. As a result, a toner image which is a visible image is formed on the photosensitive drum 1.

  The intermediate transfer belt 8 is stretched by a plurality of rollers and is rotatably supported. Along with the rotation of the intermediate transfer belt 8, the primary transfer roller 7 and the photosensitive drum 1 rotate, and a predetermined voltage is applied between the primary transfer roller 7 and the photosensitive drum 1, whereby the photosensitive member. The toner image formed on the drum 1 is transferred onto the intermediate transfer belt 8 (primary transfer).

  The paper feed unit 20 has a plurality of paper feed trays 20A and 20B in which paper P such as A3 and A4 is accommodated. The paper P transported by the transport rollers 22, 24, 26, 28, etc. from the respective paper feed trays 20A, 20B is transported to the registration roller pair 32. Note that the number of paper feed trays is not limited to two. Further, a single or a plurality of large-capacity paper feeders that can accommodate a large-capacity paper P may be connected as necessary.

  The paper P conveyed to the registration roller pair 32 has its leading end abutted against the registration roller pair 32 by the loop roller pair 30 to form a loop and the bending of the paper P in the conveyance direction D is corrected. The paper P in which the bending of the paper P is corrected is conveyed to the secondary transfer unit 34 at a predetermined timing. In the secondary transfer unit 34, the Y, M, C, and K color toner images transferred onto the intermediate transfer belt 8 are collectively transferred onto the surface of the sheet P conveyed by the resist roller pair 32 (secondary). Next transfer). The second-transferred sheet P is conveyed to the fixing unit 44 on the downstream side in the conveyance direction D.

  The fixing unit 44 includes a pressure roller and a heating roller. The fixing unit 44 fixes the toner image on the surface of the paper P to the paper P by performing pressure and heat treatment on the paper P on which the toner image has been transferred by the secondary transfer unit 34.

  The conveyance path switching unit 48 is provided on the downstream side of the fixing unit 44 in the conveyance direction D, and performs conveyance path switching control based on a selected printing mode (single-sided printing mode, double-sided printing mode, or the like). The paper P on which single-sided printing has been completed in the single-sided printing mode or the paper P on which double-sided printing has been completed in the double-sided printing mode is discharged onto the paper discharge tray by the paper discharge roller 46.

  Further, when an image is formed on the back side of the paper P in the duplex printing mode, the paper P on which the image is formed on the front side is conveyed to the ADU 60 via the conveyance roller 62 and the like. In the switchback path of the ADU 60, the reverse rotation control of the ADU roller 64 causes the rear end of the paper P to be transported to the U-turn path section, and is reversed by the transport rollers 66 and 68 provided in the U-turn path section. In this state, the paper is fed again to the secondary transfer unit 34.

[Configuration Example of Cleaning Unit 200]
FIG. 2 shows an example of the configuration of the cleaning unit 200. As shown in FIG. 2, the cleaning unit 200 includes a cleaning device 210 and a lubricant application unit 220A. The cleaning device 210 has a cleaning blade 212 made of an elastic material such as urethane and disposed upstream of the lubricant application unit 220A in the rotational direction Db of the photosensitive drum 1. The cleaning blade 212 is disposed so that one end thereof is in contact with the surface of the photosensitive drum 1, and peels off the toner image remaining on the surface of the photosensitive drum 1.

[Configuration Example of Lubricant Application Unit 220A]
The lubricant application part 220A includes a lubricant application brush 222, a lubricant 224, a support member 226, a pressing member 228, guide members 230a and 230b, and rail members 240a and 240b. First, the control unit 250, the photoreceptor driving unit 260, and the brush driving unit 270 that drive and control the lubricant application unit 220A will be described.

  The control unit 250 includes a CPU (Central Processing Unit) that controls the entire apparatus, a ROM (Read Only Memory) that stores control software and data, and a RAM (Random Access Memory) that constitutes a work area of the CPU. have. Each of the photoconductor driving unit 260 and the brush driving unit 270 is connected to the control unit 250.

  The photoconductor driving unit 260 includes, for example, a stepping motor, a DC brushless motor, and the like, and is driven based on a drive signal supplied from the control unit 250 to rotationally drive the photoconductor drum 1. The brush drive unit 270 includes, for example, a stepping motor, a DC brushless motor, and the like, and is driven based on a drive signal supplied from the control unit 250 to rotationally drive the lubricant application brush 222.

  Next, the lubricant application unit 220A will be described. The lubricant application brush 222 is made of, for example, a resin brush made of an acrylic material, and is in contact with each of the photosensitive drum 1 and the lubricant 224. The lubricant application brush 222 rotates based on the driving of the brush drive unit 270 to scrape off the lubricant 224 and attach the scraped lubricant 224 to the surface of the photosensitive drum 1. The rotation direction Da of the lubricant application brush 222 is set opposite to the rotation direction Db of the photosensitive drum 1 so that the lubricant can be efficiently attached to the surface of the photosensitive drum 1. Of course, the lubricant application brush 222 may be rotated in the same direction as the photosensitive drum 1.

  The lubricant 224 has a substantially rectangular parallelepiped shape and is made of a fatty acid metal salt such as zinc stearate (ZnSt). The lubricant 224 is mounted on the support member 226 so that the upper surface portion thereof is in contact with the lubricant application brush 222.

  The pressing member 228 is made of, for example, a compression spring, and a lower end portion is attached to an apparatus main body (not shown), and an upper end portion is attached to a lower surface portion of the support member 226. The pressing member 228 presses the lubricant 224 to the lubricant application brush 222 side (upper side) via the support member 226. The pressing member 228 expands and contracts according to the remaining amount of the lubricant 224.

  3 and 4 show an example of the configuration of the guide members 230a and 230b and the rail members 240a and 240b that constitute the lubricant application unit 220A. Note that the guide members 230a and 230b and the rail members 240a and 240b are disposed on the left and right side portions of the lubricant 224, respectively. Only the structure of 230a and the rail member 240b is demonstrated.

  As shown in FIGS. 3 and 4, the rail member 240 a is erected on the side surface side of the lubricant 224 (support member 226). The rail member 240a has a main body 242 having an elongated rectangular parallelepiped shape extending in the pressing direction D1 of the pressing member 228. A rail groove 244 is formed along the longitudinal direction of the inner surface of the main body 242 facing the lubricant 224.

  5A and 5B show an example of the configuration of the rail groove 244. As shown in FIGS. 5A and 5B, the rail groove 244 is formed so as to gradually become wider from the lower end portion of the main body 242 toward the upper end portion. Specifically, the rail groove 244 at the lower end portion of the main body 242 is configured with a width L1, and the rail groove 244 at the upper end portion of the main body 242 is configured with a width L2 that is slightly wider than the width L1. In other words, the back of the guide member 230a, which will be described later, is configured to increase toward the upper side of the main body 242.

  3 and 4, the guide member 230a is a member for moving the support member 226 to which the lubricant 224 is attached along the longitudinal direction of the rail member 240a, and the side surface portion inside the guide member 230a is the support member. It is attached to one end 226d of 226. Protrusions 234 and 236 are provided on the outer side surface of guide member 230a so as to be spaced apart in the vertical direction (pressing direction D1), and these protrusions 234 and 236 are slidably engaged with rail grooves 244 of rail member 240a. Combined.

[Example of operation of lubricant application unit 220A]
Next, an example of the operation of the lubricant application unit 220A will be described with reference to FIGS. 6A and 6B. Here, as shown in FIG. 6A and FIG. 6B, in the configuration of the lubricant application unit 220A described above, when the remaining amount of the lubricant 224 decreases, the pressing member 228 extends and the pressing force applied to the lubricant 224 by the pressing member 228 is also increased. Decrease. As a result, the contact force of the lubricant 224 with respect to the lubricant application brush 222 is reduced, so that the scraping amount of the lubricant 224 is reduced, and as a result, the amount of the lubricant 224 applied to the photosensitive drum 1 is also reduced.

  On the other hand, when the lubricant application brush 222 is rotated to scrape off the lubricant 224, the lubricant 224 vibrates due to the frictional force between the lubricant application brush 222 and the lubricant 224 during the rotation. When this vibration increases, the sliding distance between the lubricant application brush 222 and the lubricant 224 also increases, so that the lubricant 224 is largely scraped.

  Therefore, in the first embodiment, the amount of the lubricant generated in the rail member 240a of the guide member 230a is changed with respect to the remaining amount of the lubricant 224, so that a constant amount of the lubricant 224 is always applied to the photosensitive drum. 1 is applied.

  As shown in FIG. 5A and FIG. 6A, when the remaining amount of the lubricant 224 is large, the guide member 230a is located on the lower side of the rail member 240a, so that the gap between the protrusions 234 and 236 of the guide member 230a and the rail groove 244 There is almost no nigata. Therefore, the vibration of the guide member 230a in the orthogonal direction D2 orthogonal to the pressing direction D1 of the pressing member 228 can be suppressed. In this case, the pressing force for pressing the lubricant 224 by the pressing member 228 toward the lubricant application brush 222 is increased, and the amount of the lubricant 224 scraped by the lubricant application brush 222 is increased, so that a certain amount of the lubricant 224 is applied to the photosensitive drum 1. Can be applied.

  On the other hand, when the remaining amount of the lubricant 224 decreases, the support member 226 is pressed by the pressing member 228 and moves to the lubricant application brush 222 side (upper side). Along with this, the guide member 230a also moves upward along the rail member 240a, so that the gap between the protrusions 234, 236 of the guide member 230a and the rail groove 244 gradually increases. Therefore, the vibration in the orthogonal direction D2 of the guide member 230a is also increased, so that the vibration in the rotational tangential direction of the rotation direction Db of the photosensitive drum 1 is increased, and as a result, the amount of wear of the lubricant 224 can be increased. In this case, the pressing force for pressing the lubricant 224 by the pressing member 228 toward the lubricant application brush 222 is reduced, and the amount of scraping (total consumption) of the lubricant 224 by the lubricant application brush 222 is reduced, but the vibration amount to the lubricant 224 is also reduced. A certain amount of the lubricant 224 can be applied to the photosensitive drum 1 by increasing.

  Note that the amount of vibration applied to the lubricant 224 may be increased linearly or may be increased stepwise. FIG. 7 shows an example of the relationship between the amount of lubricant vibration and the total amount of lubricant consumed when vibration is applied to the lubricant 224 linearly. In FIG. 7, the vertical axis represents the lubricant vibration amount, and the horizontal axis represents the total consumption amount of the lubricant.

  In the present embodiment, as shown in FIG. 7, the width of the rail groove 244 is gradually increased from the lower side to the upper side, so that the lubricant 224 increases as the total consumption amount of the lubricant 224 increases. The amount of vibration is increased linearly.

  FIG. 8 shows an example of the relationship between the lubricant vibration amount and the total consumption amount of the lubricant when vibration is applied to the lubricant 224 in a stepped manner. In FIG. 8, the vertical axis represents the lubricant vibration amount, and the horizontal axis represents the total consumption amount of the lubricant.

  For example, by configuring the rail groove 244 to be stepwise and wide from the bottom to the top, the vibration amount of the lubricant 224 is increased stepwise as the total consumption of the lubricant 224 increases. .

  As described above, according to the first embodiment, the rail groove 244 is configured to become wider from the bottom to the top, so that when the remaining amount of the lubricant 224 decreases, the orthogonal direction of the support member 226 is obtained. The backlash at D2 is increased, and as a result, the vibration transmitted to the lubricant 224 can be increased. As a result, even if the remaining amount of the lubricant 224 decreases and the amount of the lubricant 224 scraped by the lubricant application brush 222 decreases, the amount of consumption of the lubricant 224 is increased (controlled) by increasing the vibration to the lubricant 224. )be able to. As a result, a certain amount of lubricant 224 can always be applied to the photosensitive drum 1, and the residual toner on the photosensitive drum 1 can be reliably removed.

  Further, according to the first embodiment, since the application force of the lubricant 224 can be made constant from the time when the lubricant application unit 220A is new to the end of the period, the amount of application of the lubricant 224 to the photosensitive drum 1 can be reduced. It can be stabilized. Thereby, a favorable image can be obtained.

<Second Embodiment>
The second embodiment is different from the first embodiment in that an excitation source 280 (vibration generator) is used as means for adjusting the vibration of the lubricant 224. Note that other configurations, operations, and the like of the image forming apparatus 100 are the same as those in the first embodiment, and therefore, common constituent elements are denoted by the same reference numerals and detailed description thereof is omitted.

[Configuration Example of Lubricant Application Unit 220B]
FIG. 9 shows an example of the configuration of the lubricant application unit 220B. As shown in FIG. 9, the lubricant application unit 220 </ b> B includes an excitation source 280, a lubricant application brush 222, a lubricant 224, a support member 226, and a pressing member 228.

  The support member 226 includes a support portion 226a extending in the horizontal direction and leg portions 226b and 226b extending in the vertical direction from both ends thereof. A lubricant 224 is attached to the upper surface portion of the support portion 226a.

  The excitation source 280 is attached to the outer surface side of the one leg portion 226 b of the support member 226 and vibrates based on an electric signal (electric power) supplied from the control unit 250. The vibration generated by the excitation source 280 is transmitted to the lubricant 224 via the support member 226.

  The control unit 250 acquires the rotation time of the lubricant application brush 222, the rotation time of the photosensitive drum 1 (hereinafter referred to as the rotation time of the lubricant application brush 222), and the lubricant from the acquired rotation time of the lubricant application brush 222. An electric signal corresponding to the remaining amount of 224 is supplied to the vibration source 280. The magnitude of vibration can be adjusted by varying the frequency and amplitude. Note that a sensor may be provided in the vicinity of the lubricant 224, and the remaining amount information of the lubricant 224 may be directly acquired based on the presence or absence of a detection result of the sensor.

[Operation example of lubricant application unit 220B]
FIG. 10A is a diagram for describing an example of the operation of the lubricant application unit 220B when the remaining amount of the lubricant 224 is large. FIG. 10B is a diagram for explaining an example of the operation of the lubricant application unit 220B when the remaining amount of the lubricant 224 is small.

  As illustrated in FIG. 10A, the control unit 250 determines that the remaining amount of the lubricant 224 is large when the acquired rotation time of the lubricant application brush 222 or the like is short. Based on the determination result, the controller 250 generates an electrical signal that reduces the amount of vibration of the excitation source 280 and supplies the electrical signal to the excitation source 280. The excitation source 280 vibrates with a small amount of vibration based on the electrical signal supplied from the control unit 250. For this reason, the amount of the lubricant 224 cut by vibration is reduced. In this case, the pressing force for pressing the lubricant 224 by the pressing member 228 toward the lubricant application brush 222 increases, and the amount of the lubricant 224 scraped by the lubricant application brush 222 increases. Therefore, a certain amount of the lubricant 224 is applied to the photosensitive drum 1. Can be applied.

  In contrast, as shown in FIG. 10B, when the rotation time of the acquired lubricant application brush 222 or the like is long, it is determined that the remaining amount of the lubricant 224 is small. Based on the determination result, the controller 250 generates an electrical signal that increases the amount of vibration of the excitation source 280 and supplies the electrical signal to the excitation source 280. The excitation source 280 vibrates with a large amount of vibration based on the electrical signal supplied from the control unit 250. Therefore, the amount of scraping of the lubricant 224 due to vibration increases. In this case, the pressing force that presses the lubricant 224 by the pressing member 228 toward the lubricant application brush 222 is reduced, and the amount of scraping of the lubricant 224 by the lubricant application brush 222 is also reduced. Therefore, the vibration transmitted to the lubricant 224 is reduced. It can be compensated by increasing the amount and increasing the amount of the lubricant 224 to be cut.

  As described above, according to the second embodiment, the magnitude of vibration transmitted to the lubricant 224 is varied according to the remaining amount (use time) of the lubricant 224. Therefore, the consumption of the lubricant 224 can be increased by increasing the vibration to the lubricant 224 from the decrease in the consumption of the lubricant 224 due to the decrease in the pressing force of the lubricant 224 of the pressing member 228. As a result, a certain amount of lubricant 224 can always be applied to the photosensitive drum 1, and the residual toner on the photosensitive drum 1 can be reliably removed.

<Third Embodiment>
The third embodiment is different from the first and second embodiments in that the vibration source 280 is used as means for adjusting the vibration of the lubricant 224 and the installation position of the vibration source 280 is fixed. doing. Since the configuration and operation of the other image forming apparatus 100 are the same as those in the first and second embodiments, common constituent elements are denoted by the same reference numerals and detailed description thereof is omitted. .

[Configuration Example of Lubricant Application Unit 220C]
FIG. 11 shows an example of the configuration of the lubricant application unit 220C. As shown in FIG. 11, the lubricant application unit 220 </ b> C includes an excitation source 280, a lubricant application brush 222, a lubricant 224, a support member 226, and a pressing member 228.

  The support member 226 includes a support portion 226a that extends in the horizontal direction, a leg portion 226b that extends in the vertical direction from one end portion thereof, and a leg portion 226c that extends obliquely downward from the other end portion to the outside. A lubricant 224 is attached to the upper surface portion of the support portion 226a.

  The vibration source 280 is attached to an apparatus main body (not shown) in the vicinity (peripheral part) of the support member 226 near the outer surface side of the leg part 226c, and vibrates based on an electric signal (electric power) supplied from the control unit 250. The vibration source 280 is configured to contact the leg portion 226c of the support member 226 that moves toward the lubricant application brush 222 according to the remaining amount of the lubricant 224, and to transmit vibration to the lubricant 224 via the support member 226. ing.

[Example of operation of lubricant application unit 220C]
FIG. 12A is a diagram for explaining an example of the operation of the lubricant application unit 220C when the remaining amount of the lubricant 224 is large. FIG. 12B is a diagram for describing an example of the operation of the lubricant application unit 220C when the remaining amount of the lubricant 224 is small.

  As illustrated in FIG. 12A, when the remaining amount of the lubricant 224 is large, the support member 226 is located on the lower side, and therefore the excitation source 280 is separated from the support member 226. Therefore, the vibration of the excitation source 280 is not transmitted to the lubricant 224. In this case, the pressing force for pressing the lubricant 224 by the pressing member 228 toward the lubricant application brush 222 increases, and the amount of the lubricant 224 scraped by the lubricant application brush 222 increases. Therefore, a certain amount of the lubricant 224 is applied to the photosensitive drum 1. Can be applied.

  As shown in FIG. 12B, when the remaining amount of the lubricant 224 decreases, the support member 226 moves upward (the lubricant application brush 222 side) accordingly, and the outer surface side of the leg portion 226c of the support member 226 is added. It contacts the vibration source 280. Thereby, the vibration of the vibration source 280 is transmitted to the lubricant 224 via the support member 226, so that the lubricant 224 vibrates and the amount of the lubricant 224 is increased. In this case, since the pressing force for pressing the lubricant 224 by the pressing member 228 toward the lubricant application brush 222 is reduced, and the amount of the lubricant 224 by the lubricant application brush 222 is reduced, the amount of vibration transmitted to the lubricant 224 is reduced. Can be compensated for by increasing the amount of lubricant 224 to be increased.

  In the third embodiment described above, the excitation source 280 is controlled to be constantly driven, but the present invention is not limited to this. For example, the driving of the vibration source 280 may be controlled to start when the vibration source 280 contacts the support member 226. Whether or not the vibration source 280 is in contact with the support member 226 is detected by detecting the contact state between the vibration source 280 and the support member 226, or based on the amount of lubricant 224 decreased. This can be determined by predicting the contact time. Further, the vibration amount of the vibration source 280 may be controlled to be variable according to the amount of contact between the vibration source 280 and the support member 226.

  As described above, according to the third embodiment, since the magnitude of vibration transmitted to the lubricant 224 is varied according to the remaining amount (use time) of the lubricant 224, the lubricant 224 of the pressing member 228 is changed. The consumption of the lubricant 224 can be increased by increasing the vibration to the lubricant 224 from the decrease in the consumption of the lubricant 224 due to the decrease in the pressing force. As a result, a certain amount of lubricant 224 can always be applied to the photosensitive drum 1, and the residual toner on the photosensitive drum 1 can be reliably removed.

<Fourth embodiment>
The fourth embodiment is different from the first embodiment in that a guide member 290 that supports the pressing member 228 is used as means for adjusting the vibration of the lubricant 224. Note that other configurations, operations, and the like of the image forming apparatus 100 are the same as those in the first embodiment, and therefore, common constituent elements are denoted by the same reference numerals and detailed description thereof is omitted.

[Configuration Example of Lubricant Application Unit 220D]
FIG. 13 shows an example of the configuration of the lubricant application unit 220D. As shown in FIG. 13, the lubricant application part 220 </ b> B includes a lubricant application brush 222, a lubricant 224, a support member 226, a pressing member 228, and a guide member 290.

  The support member 226 includes a support portion 226a extending in the horizontal direction and leg portions 226b and 226b extending in the vertical direction from both ends thereof. A lubricant 224 is attached to the upper surface portion of the support portion 226a.

  The guide member 290 supports the pressing member 228 in order to prevent the pressing member 228 from overturning and vibrating, and is inserted inside the compression spring constituting the pressing member 228. The upper end portion of the guide member 290 is attached to the lower surface portion of the support portion 226a of the support member 226, and the lower end portion of the guide member 290 is a free end. For example, the lower end portion of the guide member 290 is supported by a support member (not shown) so as not to move in a direction orthogonal to the pressing direction D1. Further, the length in the longitudinal direction of the guide member 290 is configured to be shorter than the length in the pressing direction D1 when the pressing member 228 is extended.

[Operation example of lubricant application unit 220D]
FIG. 14A is a diagram for explaining an example of the operation of the lubricant application unit 220D when the remaining amount of the lubricant 224 is large. FIG. 14B is a diagram for describing an example of the operation of the lubricant application unit 220D when the remaining amount of the lubricant 224 is small.

  As shown in FIG. 14A, when the remaining amount of the lubricant 224 is large (when the amount of consumption of the lubricant 224 is small), the support member 226 is positioned on the lower side due to the downward bias of the lubricant 224. Is supported by the guide member 290 over substantially its entire length. Therefore, the vibration generated when the lubricant application brush 222 rotates is suppressed. As a result, when the remaining amount of the lubricant is large, the vibration of the lubricant 224 is reduced, and the amount of consumption due to the vibration of the lubricant 224 is reduced, but the pressing force by which the lubricant 224 is pressed toward the lubricant application brush 222 by the pressing member 228 is reduced. Since the amount of the lubricant 224 scraped by the lubricant application brush 222 is large, a certain amount of the lubricant 224 can be applied to the photosensitive drum 1.

  On the other hand, as shown in FIG. 14B, when the remaining amount of the lubricant 224 decreases (when the consumption amount of the lubricant 224 is large), the support member 226 rises to the lubricant application brush 222 side by the extension of the pressing member 228. Go. As a result, the length of the guide member 290 in the longitudinal direction is shorter than the length of the pressing member 228 in the pressing direction, and the lower side of the pressing member 228 is not supported by the guide member 290. As a result, since the vibration of the lubricant 224 can be increased as the remaining amount of the lubricant 224 decreases, the consumption amount of the lubricant 224 can be increased, and a certain amount of the lubricant 224 can be applied to the photosensitive drum 1.

  As described above, according to the fourth embodiment, the guide range for guiding the pressing member 228 by the guide member 290 varies according to the remaining amount (usage time) of the lubricant 224, so the remaining amount of the lubricant 224 The vibration to the lubricant 224 can be increased as the value decreases. Thereby, the vibration transmitted to the lubricant 224 can be increased, and the consumption of the lubricant 224 can be increased accordingly. As a result, a certain amount of lubricant 224 can always be applied to the photosensitive drum 1, and the residual toner on the photosensitive drum 1 can be reliably removed.

  Although the present invention has been described using the embodiment, the technical scope of the present invention is not limited to the scope described in the embodiment. Various modifications or improvements can be added to the above-described embodiments without departing from the spirit of the present invention. For example, also in the second to fourth embodiments, as shown in FIGS. 7 and 8, the amount of vibration applied to the lubricant 224 can be increased in a linear shape or increased in a stepped manner. You can also. The image forming apparatus 100 shown in FIG. 1 forms a color image. However, the present invention is not limited to an image forming apparatus that forms a color image, but can be applied to an image forming apparatus that forms a monochrome image. it can.

1 Photosensitive drum (image carrier)
100 Image forming apparatus 222 Lubricant application brush (application brush)
228 Pressing member 230a, 230b Guide member (vibration control unit)
240a, 240b Rail member (vibration controller)
280 Excitation source (vibration control unit, excitation device)
290 Guide member (support member, vibration control unit)

Claims (6)

An image carrier for carrying a toner image;
An application brush configured to rotate and scrape off and apply a lubricant to the image carrier;
A pressing member that presses the lubricant against the application brush;
A vibration control unit that controls vibration transmitted to the lubricant in accordance with a pressing force applied to the lubricant by the pressing member;
An image forming apparatus comprising: The image forming apparatus according to claim 1, wherein the vibration control unit varies vibration according to a remaining amount of the lubricant. The vibration control unit
A support member provided between the lubricant and the pressing member and supporting the lubricant;
A guide member that is provided on a side surface of the support member and guides the support member in a pressing direction by the pressing member;
The image forming apparatus according to claim 2, wherein the guide member is configured such that a backlash between the guide member and the support member increases as the lubricant moves toward the application brush. The vibration control unit
A support member provided between the lubricant and the pressing member and supporting the lubricant;
A vibration exciter attached to the support member and transmitting vibrations to the lubricant via the support member;
The image forming apparatus according to claim 2, further comprising: The vibration control unit
A support member provided between the lubricant and the pressing member and supporting the lubricant;
An excitation device that is provided apart from the support member and transmits vibrations to the lubricant by contacting the support member that moves according to the remaining amount of the lubricant;
The image forming apparatus according to claim 2. The pressing member is composed of a compression spring,
The vibration control unit includes a guide member that supports the compression spring,
The image forming apparatus according to claim 2, wherein the guide member varies a guide range of the compression spring according to an expansion / contraction state of the compression spring.

Images