JP3765341B2 - Cleaner device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cleaner device for scraping off a developer remaining on an image carrier after transfer using a blade in an image forming apparatus such as an electrophotographic copying machine or an electrophotographic printer using a developer such as toner.
[0002]
[Prior art]
Conventionally, an image forming apparatus using an electrophotographic method has been widely used. This electrophotographic image forming apparatus will be described with reference to FIG.
[0003]
FIG. 11 is a schematic diagram showing a schematic configuration of a conventional image forming apparatus using an electrophotographic system.
[0004]
The image forming apparatus 10 includes a photosensitive drum 12 that is rotated in the direction of arrow A by a motor (not shown). A primary charger 14 is disposed opposite to the photosensitive drum 12, and the photosensitive drum 12 is uniformly charged by corona discharge by the primary charger 14. The uniformly charged photosensitive drum 12 is irradiated with light (document reflected light) 16 carrying information on an image described on a document (not shown), and an electrostatic latent image is formed on the photosensitive drum 12. The A developing device 18 for developing the electrostatic latent image is disposed downstream of the position where the photosensitive drum 12 is irradiated with the document reflected light 16 in the rotation direction of the photosensitive drum 12. The developing unit 18 has a developing sleeve 18a that is rotated in the direction of arrow B by a motor (not shown), and toner (developer) is supplied from the developing sleeve 18a to the photosensitive drum 12. When the electrostatic latent image formed on the photosensitive drum 12 comes to a position facing the developing sleeve 18a, toner is supplied to the electrostatic latent image from the developing sleeve 18a, and a toner image (developed image) is formed on the photosensitive drum 12. Is done.
[0005]
The registration rollers 20 and 20 'rotate in the directions of arrows C and C' at a timing synchronized with the moving speed of the toner image formed on the photosensitive drum 12, and a transfer material (not shown) is conveyed toward the transfer region 22. Is done. The material to be transferred fed from the registration rollers 20 and 20 ′ passes between the upper transfer guide plate 24 and the lower transfer guide plate 26 and reaches the photosensitive drum 12.
[0006]
The material to be transferred that has reached the photosensitive drum 12 is conveyed to the transfer region 22. In the transfer area 22, the toner image on the photosensitive drum 12 is transferred to the transfer material by the transfer charger 28. Thereafter, the transfer material is separated from the photosensitive drum 12 by the separation charger 30.
[0007]
A cleaner device 34 having a blade 32 is disposed downstream of the transfer region 22 in the rotation direction of the photosensitive drum 12. The blade 32 scrapes off the toner remaining on the photosensitive drum 12 after the transfer.
[0008]
An eraser 36 is disposed downstream of the cleaner device 34 in the rotation direction of the photosensitive drum 12, and the residual potential on the photosensitive drum 12 is neutralized by the eraser 36. On the other hand, the transfer material onto which the toner image has been transferred is transferred to a fixing device (not shown) by a transfer unit 38 that transfers the transfer material in the direction of arrow D. The toner image is fixed on the transfer material by the fixing device, and then the transfer material is discharged out of the apparatus to complete one copy cycle.
[0009]
As a cleaner device that removes the toner remaining on the photosensitive drum 12, a device that rotates a brush-like material such as a fiber brush or a magnetic brush in contact with the photosensitive drum 12 in addition to the above-described blade 32 is used. Yes. Among these various cleaner apparatuses, the cleaner apparatus using the blade 32 is widely used from the viewpoints of downsizing the apparatus and eliminating the need for a drive source.
[0010]
A cleaner apparatus using the blade 32 will be described with reference to FIG.
[0011]
FIG. 12A is a perspective view showing the blade, and FIG. 12B is a schematic view showing a state where the blade is pressed against the photosensitive drum 12.
[0012]
The blade 32 is made of a plate-like rubber extending in the rotation axis direction (arrow E direction) of the photosensitive drum 12, and the front end portion 32 b in the width direction of the surface 32 a on the photosensitive drum 12 side is pressed against the photosensitive drum 12. As a result, the developer remaining on the photosensitive drum 12 is scraped off.
[0013]
A blade having a shape different from that of the blade 32 shown in FIG. 12 will be described with reference to FIG.
[0014]
13 shows a blade having a shape different from that of FIG. 12, (a) is a perspective view of the blade, and (b) shows a state where the blade of (a) is pressed against the photosensitive drum 12. It is a schematic diagram.
[0015]
The rear end portion 40c of the blade 40 is held by a sheet metal 42 fixed to the apparatus main body (not shown). The blade 40 extends in the rotation axis direction (arrow E direction) of the photosensitive drum 12, and has a front end portion 40b in the width direction made of a plate-like rubber thinner than the rear end portion 40c, and a surface 40a on the photosensitive drum 12 side. When the leading end portion 40b in the width direction is pressed against the photosensitive drum 12, the developer remaining on the photosensitive drum 12 is scraped off.
[0016]
The blade 32 shown in FIG. 12 will be described in detail with reference to FIGS.
[0017]
14A and 14B are schematic views showing the blade pressed against the photosensitive drum, FIG. 14A is a schematic view showing the blade held by the holding member, and FIG. 14B is a holding member having a shape different from the holding member of FIG. It is a schematic diagram which shows the braid | blade currently hold | maintained. FIG. 15A is a schematic diagram showing a positional relationship between the blade 32 and the photosensitive drum 12, and FIG. 15B is a schematic diagram showing a part of FIG. FIG. 16 is a schematic diagram showing a state in which the blade 32 is bent when the photosensitive drum 12 rotates in the direction of arrow A.
[0018]
As shown in FIG. 14, the blade 32 is generally held by a holding member 44 and a holding member 46 at a rear end portion 32 d opposite to the tip end portion 32 b pressed against the photosensitive drum 12. These holding members 44 and 46 are fixed to the apparatus main body, a cartridge (not shown), and the like. Further, as described above, the blade 32 is disposed with respect to the photosensitive drum 12 such that the front end portion 32 b in the width direction of the surface 32 a on the photosensitive drum 12 side is pressed against the photosensitive drum 12. As a material of the blade 32, a soft material such as urethane is mainly used so as not to damage the photosensitive drum 12.
[0019]
When the photosensitive drum 12 rotates in the direction of arrow A, the blade 32 is bent (deformed) as shown in FIG. In this state, the pressing force F from the holding member 46, the repulsive force G from the photosensitive drum 12, and the elastic force H of the blade itself act on the blade 32 in this state. Therefore, as shown in FIG. 15, the thickness t of the blade 32 and the thickness of the blade 32 are minimized so that the damage of the photosensitive drum 12 is minimized while maintaining the cleaning performance of the blade 32 and the blade 32 is not turned over or excessively deformed. The length L is set appropriately. Further, in order to apply a pressing force to the blade 32, an intrusion amount x with respect to the photosensitive drum 12, an attachment angle θ with respect to a tangent line M where the blade 32 contacts the photosensitive drum 12, and the like are appropriately set. In this way, the positional relationship of the blade 32 with respect to the photosensitive drum 12 is determined in advance, and when the photosensitive drum 12 rotates in the direction of arrow A, the blade 32 maintains a predetermined deformation amount (deflection amount) to improve the cleaning performance. It is configured so that it can be maintained.
[0020]
However, the hardness of the blade 32 easily changes depending on environmental characteristics, particularly temperature. For this reason, when the temperature of the environment changes, the blade 32 may become harder or softer. As a result, the amount of deformation of the blade 32 may change and the blade may not reach a predetermined amount of deformation. In this case, the pressing position where the blade 32 presses the photosensitive drum 12 may move from the pressing position when the amount of deformation is a predetermined amount, and the pressing force may change. If the pressing force or the like is changed in this way, there is a possibility that defective cleaning or turning of the blade may occur.
[0021]
A conventional technique for solving such a problem will be described with reference to FIGS.
[0022]
FIG. 17A is a schematic view showing the blade held by the holding member, and FIG. 17B is a schematic view showing a state where the blade of FIG. 17A is pressed against the photosensitive drum. FIG. 18A is a perspective view showing another cleaner device, and FIG. 18B is a perspective view showing still another cleaner device.
[0023]
A thin plate 50 is disposed on the back surface 32c of the blade 32 shown in FIG. 17 on the opposite side of the surface 32a on the photosensitive drum 12 side, except for the tip portion close to the photosensitive drum 12. Since the thin plate 50 suppresses deformation of the blade 32 except for the tip portion close to the photosensitive drum 12, the entire blade 32 is less likely to be deformed than that without the thin plate 50. Even if the hardness of the blade 32 changes, the pressing position where the blade 32 presses the photosensitive drum 12 is difficult to move.
[0024]
Further, at both ends of the blade 32 in the longitudinal direction (arrow E direction), the pressing force for pressing the photosensitive drum 12 may be weaker than that at the longitudinal center. As a technique for solving this problem, as shown in FIG. 18A, a portion 52 a of the thin plate 52 located at both longitudinal ends 32 e of the blade 32 is located at the longitudinal central portion 32 f of the blade 32. A technique for making the blade 32 longer in the width direction than the portion 52b is known. As another technique, as shown in FIG. 18 (b), a thin plate disposed on the back surface 32c of the blade 32 is divided into separate members 54 and 56 at the longitudinal end portions 32e and the longitudinal center portion 32f of the blade 32. And the technique which changes those length and thickness is known.
[0025]
[Problems to be solved by the invention]
However, the conventional cleaner described above is configured to obtain a sufficient pressing force by setting a large amount of blade penetration x (see FIG. 15B) into the photosensitive drum in order to satisfy the cleaning function. ing. Therefore, although the pressing position where the blade presses the photosensitive drum is difficult to move, the blade has a large amount of penetration x, so that there is a problem that the surface of the photosensitive drum is scraped more than necessary and the life of the photosensitive drum is shortened.
[0026]
In addition, as described above, the pressing force that presses the photosensitive drum 12 may be weaker at both longitudinal ends of the blade than at the longitudinal central portion, so that the necessary pressing force at both longitudinal ends acts on the entire longitudinal direction. As described above, there is a cleaner device configured to satisfy the cleaning function by setting the blade penetration amount x (see FIG. 15B) and the like. In such a cleaner device, both ends in the longitudinal direction of the blade press the photosensitive drum with an appropriate pressing force, but the central portion in the longitudinal direction of the blade presses the photosensitive drum with an excessive pressing force. Become.
[0027]
By the way, in an image forming apparatus using an electrophotographic method, a corona discharge is performed in a process of charging or discharging a photosensitive drum, or a process of transferring a toner image to a transfer material and separating the transfer material from the photosensitive drum. Oxide may be generated by this, and this oxide may adhere to the photosensitive drum. When the oxide adhering to the photosensitive drum is moistened by the ambient humidity, the resistance of the surface of the photosensitive drum is lowered, and the charges forming the electrostatic latent image are hardly held on the surface of the photosensitive drum. As a result, image defects called image blur and image flow occur.
[0028]
In order to eliminate such image defects, in organic photoconductors such as OPC and inorganic photoconductors such as selenium, the surface of the photoconductor is obtained by pressing the blade of the cleaner device strongly against the surface of the photoconductor and scraping the surface little by little. The oxide adhering to is removed. Therefore, although it is necessary to cut the surface of the photosensitive drum, the life of the photosensitive drum is shortened if it is cut too much.
[0029]
In the cleaner device in which both ends in the longitudinal direction of the blade press the photosensitive drum with an appropriate pressing force as described above, but the central portion in the longitudinal direction of the blade presses the photosensitive drum with an excessive pressing force, the blade Since the photosensitive drum is not pressed with a uniform pressing force in the longitudinal direction, unevenness occurs in how the photosensitive drum is scraped. As a result, the image density is not uniform or the background is fogged. In order to solve such a problem, it is said that the pressing force of the blade should be set high. However, if the pressing force is increased, the surface of the photosensitive drum is excessively shaved and the life of the photosensitive drum is shortened.
[0030]
In view of the above circumstances, the present invention satisfies a cleaning function of pressing an image carrier with an appropriate pressing force to clean the image carrier, and a function of evenly shaving the surface layer of the image carrier by a necessary minimum amount. An object of the present invention is to provide a cleaner device.
[0031]
[Means for Solving the Problems]
In order to achieve the above object, a cleaner device of the present invention forms an electrostatic latent image on a rotating image carrier, develops the electrostatic latent image using a developer, and transfers the developed image to a transfer material. In the image forming apparatus, the front end in the width direction of the surface on the image carrier side extending in the rotation axis direction of the image carrier is pressed against the image carrier after the transfer, so that the front end In a cleaner device having a plate-like blade that scrapes off the developer remaining on the image carrier,
(1) A plurality of flexible plate-like plates stacked on the back surface opposite to the front surface of the blade, and each rear end portion being fixed to the rear end portion on the opposite side of the blade from the front end portion. A member is provided.
[0032]
Here, the plurality of flexible plate members are:
(2) The front end portion of the plurality of flexible plate-like members opposite to the rear end portion may be close to the front end portion of the blade in order from the side closer to the back surface of the blade. .
[0033]
In addition, the plurality of flexible plate-like members are
(3) In order from the side closer to the back surface of the blade, the tip of the plurality of flexible plate-like members opposite to the rear end may be far from the tip of the blade. .
[0034]
Furthermore, the plurality of flexible plate-shaped members are:
(4) The thickness of each of the plurality of flexible plate-like members may be changed in order from the side closer to the back surface of the blade.
[0035]
Furthermore, the plurality of flexible plate-like members are:
(5) The blades may be stacked on both longitudinal ends of the back surface of the blade.
[0036]
Furthermore, the plurality of flexible plate-like members are:
(6) The blade may be stacked along the longitudinal direction on the back surface, and the stacked state may be different between the central portion and the end portion in the longitudinal direction.
[0037]
Furthermore, the plurality of flexible plate-like members are:
(7) Of the plurality of flexible plate-like members, each of the tips stacked on both ends of the blade in the longitudinal direction opposite to the rear end is closer to the back surface of the blade. In this order, the blade may be far from or close to the tip of the blade.
[0038]
Furthermore, the plurality of flexible plate-like members are:
(8) Among the plurality of flexible plate-like members, the thickness of each of the portions stacked on both ends in the longitudinal direction of the blade changes in order from the side closer to the back surface of the blade. It may be.
[0039]
Furthermore, the plurality of flexible plate-like members are:
(9) The blades are stacked on the back surface in the longitudinal direction, and the portions of the plurality of flexible plate-like members located at both ends in the longitudinal direction are the center in the longitudinal direction. It may be closer to the tip of the blade than the part located in the part.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a cleaner device of the present invention will be described with reference to the drawings.
[0041]
First, the principle of the present invention will be described with reference to FIGS.
[0042]
FIG. 1 is a schematic diagram showing a schematic configuration of an example of a cleaner device provided with a blade and a plurality of flexible plate-like members stacked on the back surface of the blade, and the same components as those in FIG. Are given the same reference numerals. FIG. 2A is a schematic view showing a state in which the front end portion of one plate having a thickness t1 is fixed and stress is applied to the rear end portion, and FIG. It is a schematic diagram which shows the state which fixes the front-end | tip part of a flexible board (it is an example of the some flexible plate-shaped member said to this invention), and acts stress on a rear-end part. FIG. 3 is a schematic diagram showing a state where a plurality of flexible plates shown in FIG. 2B are bent (deformed). FIG. 4 is a graph showing a comparison of stresses required to give the same amount of deformation to one plate shown in FIG. 2A and a plurality of flexible plates shown in FIG. The vertical axis represents stress (kg / cm ² The horizontal axis represents the distance (mm) from the fulcrum P.
[0043]
As shown in FIG. 1, the cleaner device 60 includes a blade 32 and a plurality of flexible plates 62 stacked on the back surface 32 c of the blade 32. The length of the blade 32 (hereinafter, the length here means the length in the direction of the rotation axis of the photosensitive drum 12 (the direction of arrow E shown in FIG. 12)) and the length of the plurality of flexible plates 62 are the same. The length of the blade 32 is substantially the same as the length of the photosensitive drum 12. Further, the width of the blade 32 (hereinafter, the width is a width orthogonal to the rotation axis direction of the photosensitive drum 12 (the direction of arrow E shown in FIG. 12)) is 22 mm, and the thickness is 2.0 mm. It is. The thickness of each flexible plate 62 is 0.1 mm, and the material thereof is stainless steel. As the flexible plate, in addition to stainless steel, a metal such as aluminum or copper may be used. Here, three flexible plates 62 are stacked.
[0044]
The front end portion 32 b in the width direction of the surface 32 a on the photosensitive drum 12 side of the blade 32 is pressed against the photosensitive drum 12. On the other hand, the rear end portion 32d of the surface 32a opposite to the front end portion 32b in the width direction is held by the holding member 64 together with the rear end portions 62b of the three flexible plates 62. The rear end 62 b of the plate 62 is fixed to the rear end 32 d of the blade 32. Here, the distance between the tip 32b of the blade 32 and the tips 62a of the three flexible plates 62 is 4 mm.
[0045]
Next, the stress required to give the same amount of deformation to the three stacked flexible plates 62 and one plate having the same thickness as the three flexible plates 62 was compared. The experiment will be described.
[0046]
As shown in FIG. 2A, the front end 66a of a single plate 66 having a thickness t1 (1.2 mm) is displaceable and the rear end 66b is fixed to serve as a fulcrum P. Displacement Z was allowed to act. Similarly, as shown in FIG. 2B, three flexible plates 62 (total thickness t1 = 0.4 mm). × 3 ) And the rear end 62b is fixed to be a fulcrum P, and the front end 62a Displacement Z was allowed to act. In this case, as shown in FIG. 3, the three flexible plates 62 bend so that the displaceable tip portions 62a are displaced from each other.
[0047]
Comparing the case of one plate 66 shown in FIG. 2 (a) with the case of three flexible plates 62 shown in FIG. 2 (b), as shown in FIG. The one plate 66 and the three flexible plates 62 are almost the same. stress It became. However, as the distance from the fulcrum P increases, the three flexible plates 62 are deformed with a smaller stress than the one plate 66. Therefore, when the three flexible plates 62 are stacked on the back surface 32c of the blade 32 as shown in FIG. 1, a large stress acts on the rear end portion 32d held by the holding member 64 of the blade 32. However, since the flexible plate 62 is fixed to the rear end portion 32d and the deformation is suppressed, the rear end portion 32d is hardly deformed (not easily bent). On the other hand, the flexible plate 62 is not fixed to the tip 32b of the blade 32 that is pressed against the photosensitive drum 12 (see FIG. 11), and deformation is not suppressed. Easy to deform (easy to bend). For this reason, from the rear end part 32d of the blade 32 to the front end part 32b, the force for suppressing the deformation gradually decreases. As a result, it is possible to reduce the displacement of the contact position due to the change in the hardness of the blade 32 that occurs when the rear end portion 32d is easily deformed, and the tip end portion 32b maintains flexibility, so that the photosensitive drum 12 is hardly damaged. Cleanability can also be secured.
[0048]
Various examples of the cleaner device will be described with reference to FIGS.
[0049]
FIG. 5 shows a schematic configuration of an example of a cleaner device including a blade and three flexible plates (an example of a plurality of flexible plate-like members according to the present invention) stacked on the back surface of the blade. It is the schematic diagram shown, and the same code | symbol is attached | subjected to the component same as the component of FIG.
[0050]
As shown in FIG. 5, the cleaner device 70 includes a blade 32 and three flexible plates 72 stacked on the back surface 32 c of the blade 32. The length of the blade 32 and the length of the three flexible plates 72 are the same, and the length of the blade 32 is substantially the same as the length of the photosensitive drum 12. The blade 32 has a width of 22 mm and a thickness of 2 mm. Each flexible plate 72 has a thickness of 0.1 mm, a width of 18 mm, and is made of stainless steel. As the flexible plate, in addition to stainless steel, a metal such as aluminum or copper may be used. The rear end 32d of the blade 32 opposite to the front end 32b in the width direction of the surface 32a on the photosensitive drum 12 side is held by the holding member 64 together with the rear ends 72b of the three flexible plates 72. ing. The distance between the tip 32b of the blade 32 and the tips 72a of the three flexible plates 72 is 4 mm.
[0051]
As described above, the configuration in which the deformation of the blade 32 is suppressed by the three flexible plates 72 stacked on the back surface 32c of the blade 32 allows the one having no flexible plate 72 or three possible plates. Compared with the case where one thin plate having the same thickness as the flexible plate 72 is used, the force for suppressing the deformation of the blade 32 gradually decreases from the rear end portion 32d of the blade 32 to the front end portion 32b. As a result, the rear end portion 32d can obtain a rigidity that sufficiently suppresses the bending, so that the rear end portion 32d can be prevented from being greatly deformed due to the hardness change caused by the temperature of the blade 32 and the contact position is shifted. For this reason, it is not necessary to make the intrusion amount larger than necessary. Further, since the variation in the hardness of the blade 32 can be absorbed by replacing the rigidity by the backup plate, the unevenness of the photoconductor shaving can be reduced. Furthermore, since flexible bending is ensured at the tip end portion 32b, it is difficult to damage the photoconductor, the photoconductor surface layer can be prevented from being unnecessarily scraped, and cleaning properties can be ensured. Further, by changing the thickness and position of the flexible plate 72, the pressing force that the blade 32 presses against the photosensitive drum 12 can be accurately controlled.
[0052]
FIG. 6 shows a cleaner device including a blade and three flexible plates (one example of a plurality of flexible plate-like members according to the present invention) of different lengths stacked on the back surface of the blade. It is a schematic diagram which shows schematic structure of an example, and the same code | symbol is attached | subjected to the component same as the component of FIG.
[0053]
In the three flexible plates 84, 86, 88 of the cleaner device 80, the flexible plates 84, 86, 84 are arranged in order from the side closer to the back surface 32 c of the blade 32, that is, in the order of the flexible plates 88, 86, 84. The tip portions 84 a, 86 a, and 88 a of 86 and 88 are close to the tip portion 32 b of the blade 32. Specifically, the distance between the tip 32b and the tip 88a is 4 mm, the distance between the tip 32b and the tip 86a is 8 mm, and the distance between the tip 32b and the tip 84a is 12 mm. Accordingly, in the blade 32, the rear end portion 32d held by the holding member 64 is hardly bent because the deformation is suppressed by all the three flexible plates 84, 86, and 88.
[0054]
On the other hand, near the tip 32b of the blade 32, only the flexible plate 88 suppresses the deformation of the blade 32, so that it is easy to bend. For this reason, the force that suppresses the deformation more gently than that of FIG. 5 decreases from the rear end portion 32d of the blade 32 to the front end portion 32b. Further, by adjusting the distances between the tip portions 84a, 86a, 88a of the respective flexible plates 84, 86, 88 and the tip portion 32b of the blade 32, the pressing force that the blade 32 presses against the photosensitive drum 12 is accurately adjusted. It can be controlled well. As a result, the rear end portion 32d can suppress bending without depending on the rigidity of the blade 32, and can completely absorb changes in hardness and variations. Further, it is easy to obtain the cleanability of the tip end portion 32b and the flexibility to prevent the photoreceptor from being damaged.
[0055]
FIG. 7 shows a cleaner device provided with a blade and three flexible plates (one example of a plurality of flexible plate-like members according to the present invention) of different lengths stacked on the back surface of the blade. It is a schematic diagram which shows schematic structure of an example, and the same code | symbol is attached | subjected to the component same as the component of FIG.
[0056]
In the three flexible plates 94, 96, 98 of the cleaner device 90, the flexible plates 94, 96, 98 are arranged in order from the side closer to the back surface 32c of the blade 32, that is, in the order of the flexible plates 94, 96, 98. The tip portions 94 a, 96 a, and 98 a of 96 and 98 are distant from the tip portion 32 b of the blade 32. Specifically, the distance between the tip 32b and the tip 94a is 12 mm, the distance between the tip 32b and the tip 96a is 8 mm, and the distance between the tip 32b and the tip 98a is 4 mm. Accordingly, in the blade 32, at the rear end portion 32d held by the holding member 64, all of the three flexible plates 94, 96, 98 suppress the deformation of the blade 32, and the blade 32 is not easily bent.
[0057]
On the other hand, in the vicinity of the tip 32b of the blade 32, the single flexible plate 98 suppresses the deformation of the blade 32 when the blade 32 is deformed to a predetermined deformation amount or more. When the blade 32 is further deformed beyond the predetermined amount, the deformation of the blade 32 is suppressed by the two flexible plates 98 and 96. When the blade 32 is further deformed, the deformation of the blade 32 is suppressed by the three flexible plates 98, 96, 94. Therefore, as the amount of deformation of the blade 32 increases, the force for suppressing the deformation of the blade 32 increases. Therefore, the flexibility of the tip 32b of the blade 32 is not impaired as compared with the cleaner device shown in FIGS. 5 and 6, and the pressing force can be controlled. The rear end portion 32d can obtain the same effects as those of the above-described embodiment. At the front end portion 32b, since the front end portions 94a, 96a, 98a of the flexible plates 94, 96, 98 generate a subtle pressing force due to the bending of the blade 32 when it comes into contact with the photosensitive member, even more subtle contact is made. Can be set while controlling the pressure.
[0058]
FIG. 8 shows a cleaner device including a blade and three flexible plates stacked on the back surface of the blade and having different thicknesses (an example of a plurality of flexible plate-like members according to the present invention). It is a schematic block diagram which shows a part, and the same code | symbol is attached | subjected to the component same as the component of FIG.
[0059]
The thicknesses of the flexible plates 104, 106, and 108 of the cleaner device 100 are 0.2 mm, 0.15 mm, and 0.1 mm, respectively, and the lengths are 10 mm, 14 mm, and 18 mm, respectively. Each flexible plate 104, 106, 108 is in order from the side closer to the back surface 32 c of the blade 32, that is, the flexible plates 104, 106, 108, similarly to the flexible plates 94, 96, 98 shown in FIG. In the order of 108, the distal end portions 104 a, 106 a, 108 a of the respective flexible plates 104, 106, 108 are distant from the distal end portion 32 b of the blade 32. Further, as described above, the thickness of each of the flexible plates 104, 106, 108 increases as the distance from the back surface 32 c of the blade 32 increases. That is, if the lengths and thicknesses of the flexible plates 104, 106, 108 are L1, t1, L2, t2, L3, and t3, respectively, the length is L1 <L2 <L3, and the thickness is t1. >T2> t3. As a result, in the blade 32, the deformation of the rear end portion 32d held by the holding member 64 can be suppressed more strongly than that in FIG. On the other hand, the tip 32b of the blade 32 can ensure flexibility. Further, by adjusting the thickness of each flexible plate 104, 106, 108, the distance from the tip 32b of the blade 32, etc., the pressing force that the blade 32 presses against the photosensitive drum 12 can be accurately controlled. As a result, the tip 32b can obtain the same effects as those of the above-described embodiment. Since the rigidity of the rear end portion 32d can be further increased, the deformation of the holding portion of the soft blade 32 can be suppressed, and the displacement of the contact position can be suppressed as much as possible.
[0060]
FIG. 9 is a perspective view showing a cleaner device 110 including a blade and a flexible plate stacked on both longitudinal ends of the back surface of the blade. The same component as the component in FIG. The same code | symbol is attached | subjected.
[0061]
One flexible plate 112 is disposed in the longitudinal direction of the back surface 32 c of the blade 32. Two flexible plates 114 and 116 are stacked at both ends in the longitudinal direction of the flexible plate 112, respectively. The distal end portion 114 a of the flexible plate 114 is closer to the distal end portion 32 b of the blade 32 than the distal end portion 116 a of the flexible plate 116. Specifically, the distance between the tip 32b and the tip 116a is 8 mm, and the distance between the tip 32b and the tip 114a is 4 mm. Accordingly, the pressing force with which the blade 32 presses the photosensitive drum 12 is increased at both ends in the longitudinal direction of the blade 32 as compared with the case where the flexible plates 114 and 116 are not provided. Further, in the blade 32, deformation of the rear end portion 32d held by the holding member 64 is suppressed. As a result, the pressing force is substantially uniform over the longitudinal direction of the blade 32.
[0062]
FIG. 10 is a schematic diagram showing a cleaner device 120 including a blade and a plurality of flexible plates stacked along the longitudinal direction on the back surface of the blade, and has the same configuration as the components in FIG. Elements are given the same reference numerals.
[0063]
For example, the three flexible plates 122 are stacked on the back surface 32c of the blade 32 along the longitudinal direction thereof, and both end portions 122a of the flexible plate 122 positioned at both ends in the longitudinal direction of the back surface 32c. Is closer to the tip 32b of the blade 32 than the central portion 122b located at the central portion in the longitudinal direction. That is, the distance x1 between the both end portions 122a and the tip end portion 32b of the blade 32 is shorter than the distance x2 between the center portion 122b and the tip end portion 32b of the blade 32 (see the end section (b) and the center section (c)). ). Specifically, the distance x1 is 4.0 mm, and the distance x2 is 8.0 mm. Therefore, similarly to the cleaner device 110 of FIG. 9 described above, the tip 32b of the blade 32 suppresses deformation of the holding portion, so that the pressing force is substantially uniform over the longitudinal direction of the blade 32, and the displacement of the pressing position is reduced. Therefore, a sufficient cleaning effect can be obtained even with a pressing force lower than that in the prior art, and the unevenness of the photosensitive drum can be eliminated.
[0064]
【The invention's effect】
As described above, since the cleaner device of the present invention includes a plurality of flexible plate-like members, the flexibility of the tip portion that contacts the contact portion between the image carrier and the blade is not impaired, and It is possible to obtain a rigidity that suppresses deformation gradually or stepwise toward the root holding the blade. As a result, it is not necessary to apply a contact pressure more than necessary, and a reliable cleaning property can be secured even with a small contact pressure. Further, since only a small contact pressure is required, the image carrier is hardly damaged. Accordingly, the cleaner device satisfies the cleaning function of pressing the image carrier with an appropriate pressing force to clean the image carrier and the function of evenly shaving the surface layer of the image carrier by the necessary minimum amount. Furthermore, since the carrier is hardly damaged, there is no occurrence of image defects such as black stripes and white stripes on the image. Furthermore, it is possible to prevent image defects such as background stains and blurred characters on the white background due to the reduction in the film thickness due to the removal of the image carrier. Accordingly, the cycle leading to image degradation is extended, and the maintenance cycle for image carrier replacement is lengthened and the running cost is lowered.
[0065]
Here, the plurality of flexible plate-like members are arranged in order from the side closer to the back surface of the blade, and the tip end opposite to the rear end portion of the plurality of flexible plate-like members is close to the blade tip portion. In this case, since the rigidity near the root of the blade is increased, the displacement of the contact position between the image carrier and the blade is reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[0066]
In addition, the plurality of flexible plate-like members are arranged in order from the side closer to the back surface of the blade, and the tip portion opposite to the rear end portion of the plurality of flexible plate-like members is far from the tip portion of the blade. In some cases, as described above, since the rigidity near the base of the blade is increased, the displacement of the contact position between the image carrier and the blade is reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[0067]
Furthermore, when the thickness of each of the plurality of flexible plate-like members is changed in order from the side closer to the back surface of the blade, the thickness changes. Accordingly, the rigidity in the vicinity of the root of the blade is increased, so that the displacement of the contact position between the image carrier and the blade is reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[0068]
Furthermore, when a plurality of flexible plate-like members are stacked on both ends in the longitudinal direction on the back surface of the blade, the rigidity at both ends increases, so that the contact between the image carrier and the blade is increased. The displacement of the contact position is reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[0069]
Furthermore, when a plurality of flexible plate-like members are stacked along the longitudinal direction on the back surface of the blade, and the stacked state is different between the central portion and the end portion in the longitudinal direction, Since the rigidity in the vicinity of the root of the blade can be increased according to the difference in the state, the displacement of the contact position between the image carrier and the blade can be reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[0070]
Furthermore, the thickness of each of the plurality of flexible plate-like members stacked on both ends in the longitudinal direction of the blade among the plurality of flexible plate-like members is in order from the side closer to the back surface of the blade. If it is changed, the rigidity in the vicinity of the base of the blade can be increased in accordance with this change, so that the displacement of the contact position between the image carrier and the blade can be reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[0071]
Furthermore, a plurality of flexible plate-like members are stacked on the back surface of the blade in the longitudinal direction, and portions of the plurality of flexible plate-like members located at both ends in the longitudinal direction. However, if it is closer to the tip of the blade than the portion located at the center in the longitudinal direction, the rigidity of the portions located at both ends in the longitudinal direction can be increased. The displacement of the contact position can be reduced. As a result, it is not necessary to apply contact pressure more than necessary.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a schematic configuration of an embodiment of a cleaner device of the present invention.
FIG. 2A is a schematic view showing a state in which a front end portion of one plate having a thickness t1 is fixed and stress is applied to a rear end portion, and FIG. It is a schematic diagram which shows the state which fixes the front-end | tip part of a property board and applies stress to a rear-end part.
FIG. 3 is a schematic view showing a state where a plurality of flexible plates shown in FIG. 2B are bent (displaced).
4 is a graph showing a comparison of stresses required to give the same amount of displacement to one plate shown in FIG. 2 (a) and a plurality of flexible plates shown in FIG. 2 (b). The vertical axis represents stress (kg / cm ² The horizontal axis represents the distance (mm) from the fulcrum P.
FIG. 5 is a schematic diagram showing a schematic configuration of an example of a cleaner device including a blade and four flexible plates stacked on the back surface of the blade.
FIG. 6 is a schematic diagram showing a schematic configuration of an example of a cleaner device including a blade and three flexible plates stacked on the back surface of the blade and having different lengths.
FIG. 7 is a schematic diagram showing a schematic configuration of an example of a cleaner device including a blade and three flexible plates stacked on the back surface of the blade and having different lengths.
FIG. 8 is a schematic configuration diagram showing a part of a cleaner device including a blade and three flexible plates stacked on the back surface of the blade and having different thicknesses.
FIG. 9 is a perspective view showing a cleaner device including a blade and a flexible plate stacked on both longitudinal ends of the back surface of the blade.
FIG. 10 is a schematic view showing a cleaner device including a blade and a plurality of flexible plates stacked on the back surface of the blade over the longitudinal direction thereof.
FIG. 11 is a schematic diagram illustrating a schematic configuration of a conventional image forming apparatus using an electrophotographic system.
12A is a perspective view illustrating a blade, and FIG. 12B is a schematic diagram illustrating a state in which the blade is pressed against the photosensitive drum.
13 shows a blade having a shape different from that of FIG. 12, (a) is a perspective view of the blade, and (b) shows a state in which the blade of (a) is pressed against the photosensitive drum 12. FIG. It is a schematic diagram.
14A and 14B are schematic views showing the blade pressed by the photosensitive drum, FIG. 14A is a schematic diagram showing the blade held by the holding member, and FIG. 14B is a holding member having a shape different from the holding member of FIG. It is a schematic diagram which shows the braid | blade currently hold | maintained.
FIG. 15A is a schematic diagram showing a positional relationship between a blade and a photosensitive drum, and FIG. 15B is a schematic diagram showing a part of FIG.
FIG. 16 is a schematic diagram showing a state where the blade is bent when the photosensitive drum rotates in the direction of arrow A;
17A is a schematic diagram illustrating a blade held by a holding member, and FIG. 17B is a schematic diagram illustrating a state in which the blade of FIG.
FIG. 18A is a perspective view showing another cleaner device, and FIG. 18B is a perspective view showing still another cleaner device.
[Explanation of symbols]
32 blades
32a Blade surface
32b Blade tip
The back of the 32c blade
32d Rear end of blade
70, 80, 90, 100, 110, 120 Cleaner equipment
72, 84, 86, 88, 94, 96, 98, 104, 106, 108, 112, 114, 116, 122 Flexible plate

Claims (4)

In an image forming apparatus that forms an electrostatic latent image on a rotating image carrier, develops the electrostatic latent image using a developer, and transfers the developed image onto a transfer material, the direction of the rotation axis of the image carrier A plate-like shape that scrapes off the developer remaining on the image carrier by the tip portion when the tip portion in the width direction of the surface on the image carrier side is pressed against the image carrier after transfer. In a cleaner device with a blade,
A plurality of flexible plate-like members stacked and fixed on the back surface of the blade;
The plurality of flexible plate-like members are configured such that the front end in the width direction is located on the rear end side with respect to the front end in the width direction of the blade to suppress deformation of the blade, and the back surface of the blade A cleaner device, characterized in that the tip portion is close to the tip portion of the blade in order from the one close to . In an image forming apparatus that forms an electrostatic latent image on a rotating image carrier, develops the electrostatic latent image using a developer, and transfers the developed image onto a transfer material, the direction of the rotation axis of the image carrier A plate-like shape that scrapes off the developer remaining on the image carrier by the tip portion when the tip portion in the width direction of the surface on the image carrier side is pressed against the image carrier after transfer. In a cleaner device with a blade,
A plurality of flexible plate-like members stacked and fixed on the back surface of the blade;
The plurality of flexible plate-like members are configured such that the front end in the width direction is located on the rear end side with respect to the front end in the width direction of the blade to suppress deformation of the blade, and the back surface of the blade A cleaner device, characterized in that , in order from the closest to the tip, the tip is far from the tip of the blade . The plurality of flexible plate-shaped members are:
Increasing distance from the back surface of the blade cleaner apparatus according to claim 1 or 2, characterized in that the flexible plate-like member of the respective thicknesses of said plurality of thinner. The plurality of flexible plate-shaped members are:
The cleaner device according to claim 1, wherein the cleaner device is stacked at both longitudinal ends of the back surface of the blade .

Images