JP2010217717A - Cleaning device, image forming apparatus and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning device which removes residual toner by pressing a side of a blade consisting of a long plate-like elastic member on the surface of an image carrier, suppresses deviation of contact pressure in the long direction of the blade while suppressing costs, has high durability and high removing capability; and to provide an image forming apparatus, and a process cartridge. <P>SOLUTION: In the cleaning device which removes the residual toner on the photoreceptor drum 4 by pressing the blade 2 consisting of the long plate-like elastic member to the photoreceptor drum 4, a blade holder having flexibility is used as a blade holder 1 which supports the blade, and a coil spring 10 around which wire is spirally wound in the long direction of the blade 2 comes into contact with the blade holder 1 in a state that it is compressed in the direction perpendicular to the winding direction by a pressure plate 11 and the blade holder 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cleaning device that removes residual toner on an image carrier that moves on the surface, and an image forming apparatus and a process cartridge such as a copying machine, a printer, and a facsimile machine including the cleaning device.

  Since the cleaning device has a simple configuration and excellent adhesion removal performance, the edge ridge line, which is the contact side of the blade made of a long plate-like elastic member, with the image carrier is image-carrying. A blade type that is pressed against the surface of the body to remove residual toner is widely used. In the blade method, one in which one end of a plate-like blade is supported by a support, the free length portion protruding from the support is bent, and the tip ridge is pressed against the image carrier is widely known.

  In recent years, there has been an increasing demand for image quality improvement, and in order to meet the demand, toner particle size reduction and spheroidization have been promoted. By reducing the particle size, it is possible to obtain a high-definition image with higher accuracy and fineness, and by improving the spherical shape, it is possible to improve developability and transferability. However, the toner whose particle size has been reduced and spheroidized easily gets into the blade, and the cleaning device is required to have high removal performance.

  In order to improve the removal performance, it is conceivable to press the blade with a large force in order to increase the contact pressure between the edge portion of the blade and the image carrier. However, if the blade is pressed too much with a large force, the blade will be greatly warped, and the upstream surface of the cleaning blade located on the upstream side in the image carrier surface movement direction with respect to the leading edge of the blade is the surface of the surface moving member. The belly hit phenomenon that hits will occur. When the anti-hit phenomenon occurs, the contact area between the blade and the surface of the image carrier increases rapidly, so that the contact pressure (contact force per unit area) is small even if the image carrier is pressed with a large force. As a result, the removal performance deteriorates.

  Patent Document 1 describes a cleaning device that supports the entire surface on the side opposite to the image carrier side that does not have the edge portion of the blade on the side with a support made of a rigid body. This device is a so-called support method with zero protrusion, in which the entire surface is supported by the support and does not have a free length portion protruding from the support. In such a support method, even if the blade is pressed with a large force, the blade does not bend, so that the contact pressure can be increased and the removal performance can be improved.

  In the blade type cleaning device, the tip ridge line portion that contacts the image carrier of the blade is long due to the dimensional error of the blade made of a long plate-like elastic member or the attachment error of the blade to the support. Has a swell in the direction. For this reason, when it is pressed against the image carrier, a deviation of the contact pressure in the longitudinal direction may occur, and the removal performance may not be improved, or the wear amount may vary and the life may be shortened. . In the conventional support method in which one end of a blade is supported by a support, the free length of the blade protruding from the support is bent, and the tip ridge is pressed against the image carrier, the undulation is absorbed by the free length being bent. Thus, the deviation of the contact pressure can be alleviated to some extent. However, in the method of supporting the protrusion amount of zero in the above-mentioned Patent Document 1, since the bending of the blade is restricted, the undulation is absorbed only by a slight deformation of the ridge line portion of the blade, and as a result, the deviation of the contact pressure is It appears prominently without being sufficiently relaxed. For this reason, it is necessary to manage the blade with higher accuracy at the component level and to manage the pasting accuracy with higher accuracy in the assembly process so as to suppress the undulation. However, when the accuracy required for the parts and the accuracy in the assembly process are increased, the cost is increased.

  Also, even with the conventional support method of bending the free length of the blade and pressing the tip ridge line part, even if the accuracy required for the parts and the accuracy in the assembly process are low, it is possible to obtain a uniform contact pressure in the long direction. The cost can be reduced by reviewing to a lower level.

  The present invention has been made in view of the above background, and an object of the present invention is to remove the residual toner by pressing the tip ridge line portion of a blade made of a long plate-like elastic member against the surface of the image carrier. Accordingly, it is an object of the present invention to provide a cleaning device, an image forming apparatus, and a process cartridge having a high removal capability by suppressing the deviation of the contact pressure in the longitudinal direction of the blade while suppressing the cost.

In order to achieve the above object, the invention according to claim 1 is directed to press the one side extending in the longitudinal direction of the blade made of a long plate-like elastic member against the image carrier that moves on the surface, and the residual on the image carrier. In a cleaning apparatus for removing toner, a coil-shaped member in which a support body that supports the blade is made of a flexible material, and a wire is wound spirally so that the center line direction is the longitudinal direction of the blade Is compressed in a direction perpendicular to the center line direction and brought into contact with the support, and the support is pressed with the coiled member so that one side of the blade is pressed against the image carrier. It is what.
According to a second aspect of the present invention, in the cleaning apparatus of the first aspect, the support is a block-shaped support molded from a flexible material.
According to a third aspect of the present invention, in the cleaning device of the second aspect, the blade and the block-shaped support are integrally molded.
According to a fourth aspect of the present invention, there is provided a cleaning device for pressing a side extending in the longitudinal direction of a blade made of a long plate-like elastic member against an image carrier that moves on the surface to remove residual toner on the image carrier. , A coiled member in which a wire is spirally wound so that the center line direction is the longitudinal direction of the blade is attached to the apparatus main body, and the blade is coiled so that each winding portion of the coiled member abuts A pressurizing means is provided to pressurize the coiled member at a number of pressurizing points in the longitudinal direction of the blade so as to be attached to the member and press one side of the blade against the image carrier. .
According to a fifth aspect of the present invention, in the cleaning device of the fourth aspect, at least a portion fixed to the blade in the cross-sectional shape of the coiled member when cut in a direction orthogonal to the longitudinal direction. The coiled member is configured so as to have a shape having a straight portion.
According to a sixth aspect of the present invention, in the cleaning device according to any one of the first to fifth aspects, the blade is supported by the support body with a protruding amount of substantially zero.
According to a seventh aspect of the present invention, in the cleaning device according to the sixth aspect, the support member supports the blade on a surface on the upstream side with respect to the surface movement direction of the image carrier.
According to an eighth aspect of the present invention, in the cleaning device according to any one of the first to seventh aspects, the shape factor SF1 of the toner used to form a toner image on the image carrier is 100 to 150. It is a feature.
According to a ninth aspect of the present invention, there is provided a process cartridge that integrally supports an image carrier and a cleaning unit that removes residual toner on the image carrier, and is detachably formed on the main body of the image forming apparatus. The cleaning device according to any one of claims 1 to 8 is employed as the cleaning means.
The invention of claim 10 includes an image carrier, a toner image forming unit for forming a toner image on the image carrier, a transfer unit for transferring the toner image on the image carrier to a recording member, An image forming apparatus including a cleaning unit that removes residual toner on an image carrier is characterized in that the cleaning unit according to any one of claims 1 to 9 is employed as the cleaning unit.
The invention of claim 11 is directed to an image carrier, a toner image forming unit for forming a toner image on the image carrier, a transfer unit for transferring the toner image on the image carrier to a recording member, In an image forming apparatus including a cleaning unit that removes residual toner on an image carrier, an intermediate transfer member is used as the transfer unit, and an intermediate transfer member cleaning unit that removes residual toner on the intermediate transfer member is claimed. The cleaning apparatus according to any one of Items 1 to 9 is employed.

  In the present invention of claim 1, a flexible support is used as the blade support. Then, a coiled member in which a wire is spirally wound so that the center line direction becomes the longitudinal direction of the blade is compressed and brought into contact with a direction orthogonal to the center line direction so that one side of the blade is attached to the image carrier. The support was pressurized with a coiled member to be pressed. Thereby, each winding part (part corresponding to one winding of a coil) of a coil-like member pressurizes a support in a position which is different in the longitudinal direction of a blade, respectively. As a result, the support can be pressed at a number of press points in the longitudinal direction of the blade, and even if there is a undulation in the longitudinal direction at the contact portion of the blade with the image carrier, it has flexibility. The support can be bent in the longitudinal direction following the waviness and absorb the waviness. Therefore, it is possible to suppress the deviation of the contact pressure in the longitudinal direction without requiring high accuracy of the dimensional accuracy of the parts and the accuracy of the assembly process.

  In a fourth aspect of the invention, the blade is attached to the coiled member so that the respective winding portions of the coiled member in which the wire is spirally wound so that the center line direction is the longitudinal direction of the blade. Then, by pressing the coiled member at a number of pressure points in the longitudinal direction of the blade so as to press one side of the blade against the image carrier, the coiled member is deformed following the blade swell, and the blade swells. Can be absorbed. Therefore, the deviation of the contact pressure in the longitudinal direction can be suppressed without requiring high accuracy in parts accuracy and assembly process.

  As described above, according to the present invention, one side of the blade made of a long plate-like elastic member is pressed against the surface of the image carrier to remove the residual toner. There is an excellent effect that it is possible to provide a cleaning device, an image forming apparatus, and a process cartridge with high removal capability.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment. FIG. 3 is a schematic configuration diagram of a toner image forming unit. The main part schematic block diagram of a cleaning apparatus. The enlarged view of a blade holder and a blade. The figure which shows a mode that a braid | blade contacts a photosensitive drum before a blade holder pressurization. The figure which shows a mode that a braid | blade contacts a photoreceptor drum when a rigid body is used as a blade holder. The figure which shows a mode that a braid | blade contacts a photosensitive drum when a flexible thing is used as a blade holder. The model figure for description of the required number of blade holder pressurization points. It is a principal part schematic block diagram of the cleaning apparatus of the structure which pressurizes a blade holder with the winding part of a coil spring, (a) is a perspective view, (b) is sectional drawing orthogonal to a rotating shaft. The figure seen from the A direction of FIG.9 (b). FIG. 10 is a schematic configuration diagram of a main part of a cleaning device according to a first modification. The schematic perspective view of the coil support body which concerns on the modification 1. FIG. The schematic perspective view which shows the coil support body and braid | blade which concern on the modification 1. FIG. The figure explaining the mode before the pressurization in the cleaning apparatus which concerns on the modification 1. FIG. The figure explaining the mode after pressurization in the cleaning device concerning modification 1. FIG. 10 is a schematic configuration diagram of a main part showing another configuration of the cleaning device according to Modification 1, wherein (a) is a cross-sectional view orthogonal to the rotation axis, and (b) is a front view as viewed from the upstream side in the photosensitive drum rotation direction. The figure explaining the mode before the pressurization in the other structure of the cleaning apparatus which concerns on the modification 1. FIG. The figure explaining the mode after pressurization in other composition of the cleaning device concerning modification 1. FIG. 3 is a schematic configuration diagram of a main part of a cleaning device having a configuration in which a free length of a blade is bent and brought into contact with a photosensitive drum.

  Hereinafter, an embodiment in which the present invention is applied to an image forming apparatus will be described. FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present embodiment. In the image forming apparatus of FIG. 1, four toner image forming units 20Y, C, M, and K of yellow, cyan, magenta, and black are arranged in parallel, and yellow (Y) and cyan ( C) a so-called tandem type image forming apparatus that forms a full-color image by superimposing toner images of magenta (M) and black (K). Each of the toner image forming units 20Y, 20C, 20M, and 20K includes photosensitive drums 4Y, 4C, 4M, and 4K that are rotationally driven as image carriers. Further, an exposure device 45 is provided on each of the photoconductive drums 4Y, 4C, 4M, and 4K to form a latent image by exposing the photoconductive drums 4Y, C, M, and K with laser light or LED light based on image information of each color.

  Further, an intermediate transfer belt 60 as an intermediate transfer member is arranged to be movable on the surface so as to face the toner image forming portions 20Y, 20C, 20M, and 20K. The toner images of the respective colors formed on the photosensitive drums 4Y, 4C, 4M, and 4K are transferred to the intermediate transfer belt 60 at positions facing the photosensitive drums 4Y, 4C, 4M, and 4K via the intermediate transfer belt 60. Primary transfer rollers 61Y, 61C, 61M, and 61K are arranged. The primary transfer rollers 61Y, 61C, 61M, and 61K transfer the color toner images formed by the toner image forming units 20Y, 20C, 20M, and 20K, which will be described later, onto the intermediate transfer belt 60 in sequence, and then superimpose them. Form an image. Further, a secondary transfer device 65 that batch-transfers the toner images on the intermediate transfer belt 60 onto the transfer paper is disposed downstream of the primary transfer rollers 61Y, 61C, 61M, and 61K with respect to the surface movement direction of the intermediate transfer belt 60. ing. Further, a belt cleaning device 66 for removing toner remaining on the surface of the intermediate transfer belt 60 is provided downstream of the secondary transfer device 65.

  A paper feed unit 70 including a paper feed cassette 71, a paper feed roller 72, and the like is provided at the lower part of the image forming apparatus, and the transfer paper is sent out toward the registration roller 73. The registration roller 73 sends the transfer paper toward the facing portion between the intermediate transfer belt 60 and the secondary transfer device 65 in synchronization with the toner image formation timing. The full-color toner image on the intermediate transfer belt 60 is transferred onto the transfer paper by the secondary transfer device 65, and then fixed by the fixing device 90, and then discharged outside the apparatus.

Next, each toner image forming unit 20Y, C, M, and K will be described. Each of the toner image forming units 20Y, 20C, 20M, and 20K has substantially the same configuration and operation except that the color of the toner to be stored is different. Therefore, in the following description, subscripts Y, C, M, and The configuration and operation of the toner image forming unit 20 will be described with K omitted.
FIG. 2 is a schematic configuration diagram of the toner image forming unit. Around the photosensitive drum 4 of the toner image forming unit 20, various means for performing an electrophotographic process such as a charging device 40, a developing device 50, and a cleaning device 30 are arranged, and the photosensitive drum 4 is operated by a known operation. Each color toner image is formed thereon. Such a toner image forming unit 20 may be a process cartridge that is integrally formed and detachable from the main body of the image forming apparatus.

Next, the cleaning device 30 that is a feature of the present invention will be described.
The cleaning device 30 includes a cleaning blade (hereinafter simply referred to as “blade”) 2 that is a plate-like elastic member elongated in the direction of the rotation axis of the photosensitive drum 4, and a blade holder 1 as a support that supports the blade 2. A pressurizing unit that pressurizes the blade holder 1, a toner discharge screw 19 that discharges toner from the cleaning device 30, and the like. The blade 2 presses one side (tip ridge line portion) extending in the longitudinal direction against the surface of the photosensitive drum 4 to remove unnecessary deposits such as transfer residual toner on the surface of the photosensitive drum 4. In the present embodiment, urethane rubber is used as the material of the blade 2 because it is superior in wearability to the photosensitive drum 4 and its own wear resistance as compared with other elastic materials.

  FIG. 3 is a schematic configuration diagram of a main part of the cleaning device 30 of the present embodiment. In the cleaning device 30, the blade 2 is held by a flexible blade holder 1. The blade holder 1 has a block shape in which a cross-sectional shape when cut along a cross section orthogonal to the rotation axis direction of the photosensitive drum 4 is a substantially rectangular parallelepiped. Further, the entire back surface of the upstream surface forming the ridge line portion that comes into contact with the photosensitive drum 4 of the blade 2 is affixed to the flexible blade holder 1. By pressing the blade holder 1 from the direction shown, the ridge line portion of the blade 2 comes into contact with the photosensitive drum 4 with a predetermined contact pressure. In such a configuration, the force received by the tip ridge line portion of the blade 2 due to the rotation of the photosensitive drum 4 can be backed up over the entire back surface by the blade holder 1 to prevent the blade 2 from being bent, thereby reducing the contact pressure. The removal performance is improved.

  In the cleaning device 30, a number of pressurization points (arrows 3) for pressurizing the blade holder 1 so as to press the blade 2 against the photosensitive drum 4 are provided in the longitudinal direction of the blade 2. As a result, even if the blade 2 has undulations in the longitudinal direction at the ridge line portion in contact with the photosensitive drum 4, the flexible blade holder 1 undulates in the longitudinal direction following the undulations. To absorb. In this way, by using the flexible blade holder 1 and applying pressure at a large number of pressure points (arrows 3) in the longitudinal direction of the blade 2, deviation of the contact pressure in the longitudinal direction can be suppressed. it can.

  FIG. 4 is an enlarged view of the blade holder 1 and the blade 2. The blade holder 1 is an elastic body having flexibility, and a resin such as ABS, PC, PS, POM or the like is preferable. In particular, it is desirable that the linear expansion coefficient is substantially the same as that of the urethane rubber that is the material of the blade 2. Specifically, rubbers such as urethane rubber, NBR, and EPDM are desirable, but considering ozone deterioration, it is preferable to select a rubber having high ozone resistance. Further, as shown in FIG. 4, by integrally molding the blade holder 1 and the blade 2, the accuracy with respect to the undulation of the ridge line portion of the blade 2 is improved. Further, the adhesion between the blade holder 1 and the blade 2 is improved, and problems such as blade peeling are less likely to occur. Further, by making the blade holder 1 block-shaped as shown in FIG. Furthermore, since the blade holder 1 is an elastic body, there is an effect of absorbing vibration of the blade.

  As shown in FIG. 3, the blade 2 is supported on the upstream side of the blade holder 1 with respect to the rotation direction 5 of the photosensitive drum 4, and the cut surface at the time of blade molding is arranged downstream of the rotation direction of the photosensitive drum 4. Then, the air surface (or mold surface) is arranged on the upstream side in the rotation direction of the photosensitive drum 4. The cut surface has a fine cut flaw on the surface due to the cutting at the time of molding by the blade as compared with the air surface (mold surface), which causes deterioration of wear resistance. However, with such an arrangement, when the photosensitive drum 4 rotates, the cut surface is compressed and deformed, and the air surface (or mold surface) is pulled. Therefore, the wear resistance of the blade 2 can be improved.

Next, the effect of suppressing the deviation of the contact pressure in the longitudinal direction by the cleaning device 30 of the present embodiment will be described in comparison with the conventional case. 5, 6, and 7 are views showing a state in which the blade 2 is in contact with the photosensitive drum 4 from the direction A in FIG. 3.
FIG. 5 is a diagram illustrating a state in which the blade 2 before the blade holder 1 is pressed contacts the photosensitive drum 4. The amount of undulation of the blade 2 at this time is δ0.

  FIG. 6 is a diagram described in Patent Document 1 and shows a state in which the blade 2 is in contact with the photosensitive drum 4 when a rigid body is used as the blade holder 1. In this case, the blade 2 itself is deformed by pressurizing the blade holder 1 at a number of press points (arrow 3) in the longitudinal direction to absorb the swell, and the swell amount is changed from δ0 to δ1 (where δ0> δ1). ), But not enough. For this reason, the deviation of the contact pressure of the blade 2 on the photosensitive drum 4 in the longitudinal direction is large.

  FIG. 7 is a diagram illustrating a state in which the blade 2 is in contact with the photosensitive drum 4 when the cleaning device 30 according to the present embodiment is a flexible blade holder 1. In this case, in addition to the deformation of the blade 2 itself, the blade holder 1 is also deformed to absorb the undulation of the blade 2 and reduce the undulation amount from δ0 to δ2 (where δ0> δ1> δ2). Thus, by providing the blade holder 1 with flexibility, the deviation of the contact pressure of the blade 2 against the photosensitive drum 4 can be reduced as compared with the case where the blade holder 1 is a rigid body.

Next, the pressurizing condition for the blade holder 1 to bend following the waviness shape of the blade 2 in the cleaning device 30 of the present embodiment will be described.
The waviness pitch of the blade 2 absorbed by the cleaning device 30 of the present embodiment is intended to be larger than about 30 [mm]. The swell amount δ depends on the free length, material, and manufacturing method, but is assumed to be about 100 [μm]. Waviness with a pitch smaller than this is absorbed by the deformation of the tip of the blade 2 itself and adheres to the photosensitive drum 4. That is, the following description aims to absorb 100 [μm] swell of 30 [mm] pitch during pressurization.

  FIG. 8 is an explanatory diagram of the relationship between the undulation pitch of the blade 2 and the pressure point pitch. FIG. 8A shows a case where the pressure point pitch is the same as the waviness pitch. In this case, there is a possibility that the portion to be pressed cannot be pressed. For this reason, it is desirable that at least the pressure point pitch is less than half of the undulation pitch of the blade 2. FIGS. 8B and 8C show a case where the pressurizing point pitch is half the waviness pitch. With this configuration, the uneven portion can be pressed without unevenness. Furthermore, if the pressure point pitch can be made smaller than this, the swell of the target blade 2 can be absorbed by the bending of the blade holder 1.

Further, the load applied to pressurize the blade holder 1 needs to obtain a pressing force necessary for removing residual toner on the photosensitive drum 4 as well as absorbing waviness. As in the present embodiment, the support method with zero protrusion amount can provide a high linear pressure for removing small particles or spherical toner. In the conventional support method having a free length, the linear pressure can be applied. At 20 to 30 [N / m], the aim is to increase the pressing force to a linear pressure of about 80 to 150 [N / m]. Thus, in order to achieve the linear pressure necessary to obtain good cleaning performance at a plurality of pressing points,
(1) Ensuring a pressing point that is half or less of the undulation pitch of the blade.
(2) The blade linear pressure can be realized by the number of pressing points in (1).
These two conditions are necessary, whereby a necessary pressing force can be obtained while causing the undulation of the blade 2 to follow the photosensitive drum 4 and good cleaning performance can be obtained.

The example of the concrete conditions which enable such a structure is shown below.
The blade holder 1 is a general resin such as ABS having flexibility, and has a Young's modulus E of 2000 [Mpa] and 3000 [Mpa]. Moreover, the cross-sectional shape of the blade holder 1 is a rectangle, the width b is changed to 15 [mm], and the thickness h is changed. Table 1 shows the result of calculating how many pressurization points can be arranged within the undulation pitch 30 [mm] of the blade 2 under the condition where the target linear pressure is 80 [N / m].

  As shown in Table 1, when the Young's modulus E of the blade holder 1 is 2000 [Mpa], the thickness h needs to be 1.4 [mm] or less. When the Young's modulus E of the blade holder 1 is 3000 [Mpa], the thickness h needs to be 1.2 [mm] or less.

Furthermore, when the target linear pressure is increased to 150 [N / m] with the blade holder 1 and the blade 2 under these conditions, how many pressure points can be arranged within the undulation pitch 30 [mm] of the blade 2. The results of calculating are shown in Table 2.

  As shown in Table 2, when the Young's modulus E of the blade holder 1 is 2000 [Mpa], the thickness h may be 1.6 [mm], and when the Young's modulus E is 3000 [Mpa], the thickness h h may be 1.4 [mm], and it can be seen that the degree of freedom of the thickness of the blade holder 1 is further increased when the target linear pressure is 150 [N / m].

  In this way, the swell pitch of the blade 2 to be absorbed is set to 30 mm, and the pressure point pitch is set to 15 [mm], which is half of that. That is, the number of pressurization points is the required number obtained by dividing the length of the blade 2 by the pressurization point pitch of 15 [mm] +1, and this is the number of pressurization points. For example, if the total length 330 [mm] of the blade 2 is 22 + 1, the pressure point is 23 points. Of course, the swell of the target to be absorbed is also related to the amount of deformation of the blade, so that the required number of pressing points changes each time.

  In this way, the cleaning device 30 having a flexible blade holder 1 is used, and the blade holder 1 is pressurized at the required number of pressurization points (arrow 3) in the longitudinal direction of the blade 2. Thus, 100 [μm] swell of 30 [mm] pitch can be absorbed during pressurization, and deviation of the contact pressure in the longitudinal direction can be suppressed. Therefore, it is possible to obtain a good cleaning performance by maintaining a uniform contact pressure in the longitudinal direction without requiring high accuracy of the blade 2 component accuracy or the blade 2 assembly process.

Next, a specific configuration that satisfies the above conditions will be described.
As a configuration in which a plurality of pressurization points are provided, for example, a configuration in which a plurality of pressurization points are provided by providing a plurality of coil springs in the longitudinal direction and compressing each coil spring is conceivable. However, in this case, the number of parts increases and costs increase, and the number of assembly steps also increases, resulting in an expensive unit or device. In addition, it becomes difficult to install the pressurization points at a pitch shorter than the outer diameter of the coil spring, and restrictions are imposed when pressurizing at a narrow pitch. It is also conceivable to provide a plurality of pressing points by making the pressing member into a comb-like shape, bringing the tip of the comb-tooth portion into contact with the blade holder 1 and using the comb-tooth portion as a leaf spring. However, since the variation in the tip position becomes a direct weight variation, there is a problem in accuracy management.

Therefore, in the present embodiment, as shown in FIG. 9, a coil spring 10 that is a coil-shaped member is attached to the blade holder 1 so that the center line direction is the longitudinal direction of the blade. It was compressed in a direction perpendicular to (compression / extension direction) and brought into contact with the blade holder 1.
One end of the coil spring 10 is attached to one end in the longitudinal direction of the blade holder 1, and the other end in the longitudinal direction of the blade holder 1 is attached. A rigid pressure plate 11 is in contact with the side of the coil spring 10 opposite to the contact portion with the blade holder 1, and the cylindrical outer diameter of the coil spring 10 is compressed between the blade holder 1 and the pressure plate 11. is doing. Thereby, each winding part of the coil spring 10 becomes a compression spring, and as shown in FIG. 10, the blade holder 1 is pressurized at a contact part with the blade holder of each winding part of the coil spring. As a result, the blade holder 1 can be pressurized at a number of pressure points. In addition, a winding part is one winding part of a coil spring. As a result, the blade holder 1 can be pressurized at the required number of multiple pressing points in the longitudinal direction of the blade 2. As a result, it is possible to reliably pressurize the portion to be suppressed, absorb 100 [μm] swell of 30 [mm] pitch during pressing, and suppress the deviation of the contact pressure in the longitudinal direction. Therefore, it is possible to obtain a good cleaning performance without requiring high precision of the component accuracy of the blade 2 and the accuracy of the assembly process of the blade 2. Further, the blade holder 1 can be pressurized at a number of pressurization points with a single member, and a plurality of pressurization points can be obtained by compressing each coil spring in the direction of the center line using a plurality of coil springs. Compared with what is formed, the number of parts can be reduced, and the cost of the apparatus can be suppressed.

  Moreover, since the blade holder 2 is in point contact, the tip ridge line portion of the blade 2 can be favorably pressed to the photosensitive drum side, and the undulation of the blade 2 can be satisfactorily suppressed.

<Modification 1>
FIG. 11 is a schematic configuration diagram of a main part of the cleaning device 30 according to the first modification. FIGS. 12 and 13 are explanatory diagrams of the configuration of the blade holder 1 according to the first modification. In the cleaning device 30 of the first modification, a coil-shaped member (hereinafter referred to as a coil support 101) is used as the flexible blade holder 1. In the drawings, there are gaps between the winding parts for easy understanding, but in actuality, there are no such gaps, and the winding coils are in close contact with each other. The coil wire diameter pitch of the coil support 101 can be arbitrarily selected, for example, 0.5 [mm] or 1 [mm], and the rigidity of the coil support 101 can be adjusted by the winding diameter, material, and the like. The coil support 101 has a substantially rectangular cross section, and a portion that contacts the back surface of the blade 2 is linear. The coil support 101 is fixed to the blade by bonding or integrally molding to the entire back surface of the upstream surface forming the ridge line portion that contacts the photosensitive drum 4 of the blade 2. By making the portion that contacts the back surface of the blade 2 of the coil support 101 linear, it is possible to secure a bonding surface when the blade 2 is bonded and molded, thereby preventing blade peeling and flatness deterioration. be able to. Moreover, since the coil support body 101 can be manufactured by the manufacturing method of a normal coil spring, it can be manufactured cheaply and easily.

  FIG. 14 is a diagram showing a state before pressurizing by the pressurizing means, and FIG. 15 is a diagram showing a state after pressurizing by the pressurizing means. As shown in FIG. 14, undulation is generated at the tip ridge line portion of the blade 2 in a state before pressurization. Then, as shown in FIG. 15, when the coil support 101 is pressed at a large number of pressing points (arrow 3), the coil support 101 is deformed following the swell, and the swell of the blade 2 can be absorbed. . Therefore, the deviation of the contact pressure in the long direction can be suppressed. Further, by using the coil support body 101 as the blade holder 1, as described above, “flexure (flexure due to bending) using the rigidity of the material as in the case of using a flexible material as the support body. ”Can be caused to follow the swell by shifting each winding part. Therefore, it is possible to follow a steep swell as compared with a swell according to the bending of the flexible material. Therefore, a steep undulation portion can also be absorbed by the coil support 101, and the deviation of the contact pressure in the longitudinal direction can be further suppressed. Further, by bringing the winding portion of the coil support 101 into close contact, the pitch can be made the coil wire diameter, and the coil support 101 can be made to follow the swell of the blade more.

In addition, as shown in FIG. 16, the coil support 101 may be pressurized with a bag-like elastic member so-called balloon-like structure 6 in which liquid or gas is sealed.
As shown in FIGS. 16A and 16B, the balloon-like structure 6 is in contact with the coil support 101. A pressure plate 7 a is in contact with the balloon structure 6 on the side opposite to the contact portion with the coil support 101. For example, a pressure spring 7 is provided between the pressure plate 7 a and the casing 31. . Thus, the blade 2 is pressed through the coil support 101 while the balloon-like structure 6 is pressed against the coil support 101 by the pressurizing spring 7.

FIG. 17 is a diagram showing a state before pressurization with the balloon-like structure 6, and FIG. 18 is a diagram showing a state after pressurization with the balloon-like structure 6.
As shown in FIG. 17, undulation is generated at the tip ridge line portion of the blade before pressurization by the balloon structure 6. When an external force is applied to the internal liquid or gas through a part of the balloon-like structure 6 by the pressurizing spring 7, the external force is transmitted almost evenly in all directions by the liquid or gas. A substantially uniform pressure can be obtained over the entire surface. When the coil support body 101 is deformed by the pressure from the balloon-like structure 6 in a direction to absorb the swell of the blade, the balloon-like structure 6 is appropriately deformed so as to follow the deformation of the coil support 101. The shape holding member 101 is continuously pressed with a substantially uniform force in the longitudinal direction. In this way, since the balloon-like structure 6 presses the coil-shaped holding member 101 continuously and substantially uniformly over the lengthwise direction, it is possible to reliably press the portion to be pressed, and as shown in FIG. The support 101 can reliably absorb the undulation of the blade 2. Further, by using the balloon-like structure 6 that can be continuously pressurized over the entire width in the longitudinal direction, compared to a pressurizing means that pressurizes discontinuously at a plurality of pressure points in the longitudinal direction. A substantially uniform pressure can be applied following the shape of the bent blade holder 1, and the contact pressure of the blade 2 can be made more uniform.

The cleaning device 30 configured as described above is particularly effective for small-diameter, spherical toner that requires high removal capability. Accordingly, the image forming apparatus according to the present embodiment can use a toner shape factor SF1 of 100 to 150 used for forming a toner image. The toner shape factor SF1 is a numerical value indicating the ratio of the roundness of the shape of the spherical material, and the square of the maximum length MXLNG of the elliptical shape formed by projecting the spherical material on a two-dimensional plane is divided by the graphic area AREA. And expressed by a value multiplied by 100π / 4.
That is, SF1 = {(MXLNG) ² / AREA} × (100π / 4).

  As described above, in the present embodiment, the entire back surface of the upstream side surface forming the ridge line portion of the blade 2 is attached to the blade holder 1, and the force received by the ridge line portion of the blade 2 is backed up by the blade holder 1 over the entire back surface. The present invention has been described by using the cleaning device 30 that employs a so-called zero protrusion support method that prevents the bending of the projection. However, the present invention is not limited to this, and as shown in FIG. 19, one end of the blade 2 is supported by the blade holder 1, the free length is bent, and the leading edge portion is brought into contact with the photosensitive drum 4. The present invention can also be applied to the cleaning device having the configuration, and the same effect can be obtained. In this case, even if the accuracy required for the blade 2 at the component level or the accuracy in the assembly process is low, a uniform contact pressure can be obtained in the longitudinal direction, and costs can be reduced by reducing these accuracy. .

  In the present embodiment, the present invention has been described using the cleaning device that removes the residual toner on the photosensitive drum 4. However, the present invention is applied to the belt cleaning device 66 that removes the transfer residual toner on the intermediate transfer belt 60. It is also possible to obtain the same effect.

  The cleaning device 30 of the present embodiment presses one side extending in the longitudinal direction of the blade 2 made of a long plate-like elastic member against the photosensitive drum 4 which is an image carrier that moves on the surface, and the residual on the photosensitive drum 4. The toner is removed. The blade 2 is supported by a blade holder 1 as a flexible support. The blade holder 1 is brought into contact with the blade holder 1 by compressing a coil spring 10 that is a coil-like member in a direction perpendicular to the center line direction so that the center line direction is the longitudinal direction of the blade 2. . With this configuration, each winding portion of the coil spring 10 is compressed and deformed to become a compression spring, and each winding portion pressurizes the blade holder 1. As a result, the blade holder 1 can be pressurized at a number of pressure points in the longitudinal direction of the blade 2. Therefore, the blade holder 1 can be bent in the longitudinal direction to absorb the blade 1 swell, and the contact pressure in the longitudinal direction can be reduced without requiring high dimensional accuracy and assembly process accuracy. Deviation can be suppressed.

  Further, since the blade holder 1 has a block shape molded from a flexible material, it is difficult for the blade to vibrate and generate abnormal noise.

  Further, since the blade 2 and the block-shaped blade holder 1 are integrally molded, the accuracy of the waviness of the ridge portion of the blade 2 is improved. Further, the adhesion between the blade holder 1 and the blade 2 is improved, and problems such as blade peeling are less likely to occur.

  Moreover, as shown in the modification 1, the coil support body 101 which is a coil-shaped member may be used as a support body. The coil support 101 has the center line direction facing the longitudinal direction of the blade, and the blade 2 is attached to the coil support 101 so that each winding portion of the coil support 101 abuts. The coil support 101 is pressed at a number of pressing points in the longitudinal direction of the blade 2 so as to press one side of the blade 2 against the photosensitive drum 4, so that the coil support 101 is deformed following the swell of the blade. It can absorb the swell of the blade. Therefore, it is possible to suppress the deviation of the contact pressure in the longitudinal direction without requiring high accuracy of the dimensional accuracy of the parts and the accuracy of the assembly process. In addition, by using the coil support 101 as the blade support, it is possible to follow a steep swell and absorb the steep swell.

  Moreover, in the cross-sectional shape of the coil-shaped support body when the coil support body 101 is cut in a direction orthogonal to the longitudinal direction, at least a portion in contact with the blade has a linear portion. Thereby, the contact area of a coil-shaped support body and a braid | blade becomes large, and the coil-shaped support body 101 can be fixed to the braid | blade 2 favorably.

  Further, since the blade 2 is supported by the blade holder 1 so that the protruding amount is substantially zero, it is possible to suppress the bending of the blade, increase the contact pressure, and improve the removal performance.

  Further, the shape factor SF1 of the toner used for forming the toner image is 100 to 150. When such a toner is used, the cleaning device is particularly effective because it requires a high removal capability.

  Further, by providing a process cartridge that integrally supports the photosensitive drum 4 and the cleaning device 30 and is detachably formed on the main body of the image forming apparatus, the maintainability can be improved.

1: Blade holder 2: Blade 3: Pressing point 4: Photosensitive drum 5: Rotating direction of the photosensitive drum 6: Balloon-shaped structure 7: Pressure spring 10: Coil spring 11: Pressure plate 30: Cleaning device 101: Coil support

JP 2007-033503 A

Claims (11)

In the cleaning device for removing the residual toner on the image carrier by pressing one side extending in the longitudinal direction of the blade made of a long plate-like elastic member against the image carrier that moves on the surface,
The support that supports the blade is made of a flexible material,
A coiled member in which a wire is spirally wound so that the center line direction is the longitudinal direction of the blade is compressed in a direction perpendicular to the center line direction and brought into contact with the support, and one side of the blade is A cleaning apparatus, wherein the support is pressurized with the coiled member so as to be pressed against the image carrier.   2. The cleaning device according to claim 1, wherein the support is a block-like support molded from a flexible material.   3. The cleaning device according to claim 2, wherein the blade and the block-shaped support are integrally molded. In the cleaning device for removing the residual toner on the image carrier by pressing one side extending in the longitudinal direction of the blade made of a long plate-like elastic member against the image carrier that moves on the surface,
A coiled member in which a wire is spirally wound so that the center line direction is the longitudinal direction of the blade is attached to the apparatus body,
The blade is attached to the coil-shaped member so that the winding portions of the coil-shaped member are in contact with each other,
A cleaning apparatus comprising pressure means for pressing the coiled member at a plurality of pressure points in the longitudinal direction of the blade so as to press one side of the blade against the image carrier. The cleaning device according to claim 4.
In the cross-sectional shape of the coil-shaped member when cut in a direction orthogonal to the longitudinal direction, the coil-shaped member is configured such that at least a portion fixed to the blade has a straight portion. A cleaning device.   6. The cleaning device according to claim 1, wherein the blade is supported by the support body with a protruding amount of substantially zero.   7. The cleaning apparatus according to claim 6, wherein the support member supports the blade on a surface on the upstream side with respect to a surface movement direction of the image carrier.   8. The cleaning device according to claim 1, wherein a shape factor SF1 of toner used for forming a toner image on the image carrier is 100 to 150. In a process cartridge that integrally supports an image carrier and a cleaning unit that removes residual toner on the image carrier and is detachably formed on the image forming apparatus main body,
9. A process cartridge comprising the cleaning device according to claim 1 as the cleaning means. An image carrier, toner image forming means for forming a toner image on the image carrier, transfer means for transferring the toner image on the image carrier to a recording medium, and removing residual toner on the image carrier. In an image forming apparatus provided with a cleaning means
An image forming apparatus using the cleaning device according to claim 1 as the cleaning means. An image carrier, toner image forming means for forming a toner image on the image carrier, transfer means for transferring the toner image on the image carrier to a recording medium, and removing residual toner on the image carrier. In an image forming apparatus provided with a cleaning means
An image forming apparatus using the cleaning device according to claim 1 as an intermediate transfer member cleaning unit that uses an intermediate transfer member as the transfer unit and removes residual toner on the intermediate transfer member. .

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