JP2009086658A - Developing roller and its manufacturing method, developing device, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a developing roller having a margin to the lowering of conveying amount caused by aging of the surface of sleeve base material, capable of suppressing the lowering of the conveying amount caused by deterioration (wear) of developer 1 and preventing unevenness of an image; a process cartridge; an image forming apparatus having the process cartridge; and a method of manufacturing the developing roller. <P>SOLUTION: The developing roller has a magnet roller and a developing sleeve including the magnet roller and also attracting magnetic particles on its outer surface by magnetic force of the magnet roller. In the developing roller, a wear-resistant layer composed of material harder than a material composing the sleeve base material is provided on the outer surface of the sleeve base material in the developing sleeve, and also elliptical recesses are provided at random on the wear-resistant layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a developing roller used in a developing device mounted on an image forming apparatus such as a copying machine, a printer, or a facsimile machine. More specifically, the present invention relates to a two-component development system composed of toner and magnetic particles. The present invention also relates to a developing device, a process cartridge, and an image forming apparatus having such a developing roller.

  In order to carry the developer on the developing sleeve of the developing roller used in the image forming apparatus and to reliably convey the developer to the photosensitive drum, it has been conventional to form irregularities on the surface by sandblasting or V-groove processing. Developed sleeves were used.

  In the developing sleeve subjected to the sandblasting, the unevenness formed on the outer surface of the sleeve base 2 is fine and sharp (FIG. 20A shows a model cross-sectional view near the outer surface). As a result, the unevenness is gradually worn (see FIG. 20B), and as the number of print histories increases, that is, due to aging, the unevenness described above is scraped and flattened. As a result, the transport amount of the developer 1 Is gradually reduced, which causes a problem that an image to be formed becomes gradually thinner. In addition, since sandblasting is a process in which abrasive grains collide from one direction, the sleeve tends to run out easily, and image unevenness occurs at the rotational pitch of the sleeve.

  On the other hand, the V-groove in the developing sleeve having the above-described V-groove shape formed on the outer surface is much larger than the unevenness formed by sandblasting. As described above, since the V-groove of the developing sleeve which is much larger than the magnetic carrier of the developer 1 is not easily worn, the transport amount of the developer 1 is not easily lowered even after long-term use. However, in the developing sleeve having the V-groove formed on the outer surface in this way, the developer conveyed in the region 1a where the V-groove is formed is more than the developer 1 conveyed in the outer periphery of the V-groove (region without the V-groove) 1b. Therefore, density unevenness due to uneven transport amount of the developer 1 (see FIG. 20C) tends to occur in the formed image.

  In view of the above problems, Patent Document 1 proposes a developing roller that can suppress a decrease in the conveyance amount of the developer 1 due to secular change and can prevent image unevenness.

  According to such a technique proposed by Patent Document 1, since the development sleeve surface has a larger oval-shaped recess than the recess formed on the sleeve surface by sandblasting, the wear of the recess due to aging changes. And a decrease in the transport amount can be suppressed as compared with the developing sleeve subjected to sandblasting.

  In addition, since the oval dents formed on the surface of the sleeve base 2 are randomly arranged, it is possible to prevent the occurrence of image unevenness.

  However, the wear of the sleeve base 2 in the developing sleeve portion cannot be completely suppressed. For this reason, as the surface of the sleeve base 2 is worn, the transport amount gradually decreases. Further, as shown in FIG. 21, it is difficult to suppress the influence of aging of the developer 1 composed of the toner 3 and the magnetic carrier 135. That is, the surface of the magnetic carrier 135 is gradually rounded due to aging and rounded, thereby reducing friction with the sleeve surface and reducing the transport amount of the developer 1 (modeled in FIG. 21A). Change from the state shown to the state shown in FIG. 21B as a model).

  In addition, according to the technique proposed by Patent Document 2, by providing a soft surface treatment layer only in the valley of the sleeve surface that has been sandblasted, by previously forming a surface state that imitates the surface state over time, A decrease in the transport amount of the developer over time can be suppressed. However, since such surface processing is performed by sandblast processing, image unevenness occurs at the rotation pitch of the sleeve.

  Further, according to the technique proposed in Patent Document 3, a roughness forming member is affixed to the sleeve base to form irregularities on the sleeve surface, and the hardness of the roughness forming member is higher than that of the sleeve base. By doing so, the concave portion (sleeve base material) having a low hardness is more easily worn than the convex portion having a high hardness (roughness forming member), and this causes a difference in unevenness on the surface to increase over time. Even if the conveyance amount is reduced due to the deterioration of the depth, the dent depth can be secured and a sufficient conveyance amount can be obtained, so that an effect that the reduction in the conveyance amount can be suppressed can be obtained. However, the unevenness due to the roughness forming member is caused by unevenness in the transport amount of the developer in the formed image because the amount of developer transported in the region where the protrusion is formed is smaller than the recess in the region where the protrusion is formed. There still remains a problem that uneven density tends to occur.

Further, according to the technique proposed by Patent Document 4, the surface of the sleeve base material is provided with irregularities and then hard metal plating is performed on the surface, thereby suppressing surface wear and the amount of developer transported over time. The decrease can be suppressed. However, since a uniform metal plating layer that is less conductive than the sleeve base material is formed on the entire surface of the sleeve, the charged charge of the toner is less likely to leak from the plating layer, resulting in uneven density due to toner charge-up. It becomes easy to do.
Japanese Patent Application No. 2005-06485 JP 2003-330263 A JP 2007-94286 A JP 2000-98733 A

  The present invention has been made in view of the above problems, and has a high margin with respect to a decrease in conveyance amount due to aging of the surface of the sleeve base material, and suppresses a decrease in conveyance amount due to deterioration (wear) of the developer 1. An object of the present invention is to provide a developing roller capable of preventing image unevenness, a process cartridge and an image forming apparatus including such a developing roller, and a method of manufacturing the developing roller.

  In order to solve the above problems, a developing roller according to the present invention includes a magnet roller and a developing sleeve that encloses the magnet roller and attracts magnetic particles to the outer surface by the magnetic force of the magnet roller. In the developing roller, a wear-resistant layer made of a material harder than a material constituting the sleeve base is provided on the outer surface of the sleeve base in the developing sleeve, and the wear resistance The developing roller is characterized in that elliptical recesses are randomly provided in the layer.

  According to a second aspect of the present invention, there is provided the developing roller according to the first aspect, wherein the sleeve base material is exposed at the bottom of the elliptical recess and in the vicinity of the bottom. It is characterized by that.

  According to a third aspect of the present invention, there is provided the developing roller according to the first or second aspect, wherein the sleeve base material has a cylindrical shape and the oval-shaped recess. The elliptical longitudinal direction includes more elliptical dents along the circumferential direction of the sleeve base material than the elliptical dents along the axial direction of the sleeve base material. And

  The developing roller according to the present invention is the developing roller according to any one of claims 1 to 3, wherein the sleeve base is made of aluminum or an aluminum alloy. And the said abrasion-resistant layer is comprised by electroconductive alumite, It is characterized by the above-mentioned.

  According to a fifth aspect of the present invention, in the developing roller according to any one of the first to third aspects, the wear-resistant layer is made of nickel. And

  According to a sixth aspect of the present invention, in the developing roller according to any one of the first to third aspects, the wear-resistant layer is made of chromium. And

  According to a seventh aspect of the present invention, there is provided a developing device comprising the developing roller according to any one of the first to sixth aspects.

  A process cartridge according to the present invention comprises the developing device according to claim 7 as described in claim 8.

  According to a ninth aspect of the present invention, there is provided an image forming apparatus comprising the developing device according to the seventh aspect.

  According to a tenth aspect of the present invention, there is provided a method for producing the developing roller according to the tenth aspect of the present invention, after the cylindrical developing sleeve having a wear-resistant layer on the outer surface and the short wire rod material are accommodated in the accommodating tank. A rotating magnetic field is generated in the storage tank, the developing sleeve is rotated about its axial center, and the linear member is caused to collide with the developing sleeve material while being rotated. 6. The developing roller manufacturing method according to claim 1, wherein a recess is formed on the surface.

  According to the developing roller of the present invention, the developing sleeve includes a magnet roller and a developing sleeve that encloses the magnet roller and attracts magnetic particles to the outer surface by the magnetic force of the magnet roller. Is provided with a wear-resistant layer made of a material harder than the material constituting the sleeve base material, and the wear-resistant layer has a lot of oval-shaped dents randomly ( Therefore, it is possible to suppress a decrease in unevenness on the outer surface of the developing sleeve, and to suppress a decrease in developer conveyance amount due to secular change. In addition, since the unevenness is arranged in a large number (in plural) in a random manner, the unevenness of the developer 1 can be prevented and the unevenness of the image density can be prevented.

  In addition, since the wear-resistant layer is provided with a dent, the thickness of the wear-resistant layer at the bottom of the dent becomes thin, or the sleeve base material is exposed, so that the toner is charged from the bottom of the dent. Charges are likely to leak and image density unevenness due to toner charge-up can be prevented.

  According to the developing roller of the present invention as set forth in claim 2, the sleeve base material is exposed at the bottom of the elliptical recess and in the vicinity of the bottom, and the wear resistance is formed at the bottom of the recess. The structure has no sex layer. Thus, when the wear-resistant layer is not provided (removed) at the bottom of the recess, the recess bottom without the surface treatment is more easily worn than the surface having the surface treatment layer 5, and the surface The difference in unevenness becomes large, and even if the transport amount is reduced due to the deterioration of the developer, the dent depth can be ensured and a sufficient transport amount can be obtained, so that a decrease in the transport amount can be suppressed. Furthermore, the charged charge of the toner is likely to leak from the bottom of the dent, and the occurrence of image density unevenness due to toner charge-up can be prevented more reliably.

  According to the developing roller of the present invention described in claim 3, the sleeve base material has a cylindrical shape, and the elliptical recess has an elliptical longitudinal direction in the axial direction of the sleeve base material. The developer to be pumped up is arranged along the axial direction by the configuration in which the longitudinal direction of the ellipse includes more of the elliptical depressions along the circumferential direction of the sleeve base material than the elliptical depressions along the axial direction. Even when the developing sleeve rotates, the pumped-up developer is less likely to drop off from the surface of the developing sleeve, and the oval-shaped dent has the same effect as the conventional V-groove formation. A sufficient pumping amount can be secured.

  According to the developing roller of the present invention described in claim 4, the sleeve base is made of aluminum or an aluminum alloy, and the wear-resistant layer is made of conductive alumite. In addition, the wear resistance is remarkably improved, the change with time is small, and the pumping amount of the developer is maintained for a long period.

  According to the developing roller of the present invention described in claim 5, the wear-resistant layer is made of nickel, so that the wear resistance is improved, the change with time is small, and the amount of the developer drawn up is small. Maintained for a long time.

  According to the developing roller of the present invention described in claim 6, the wear-resistant layer is made of chrome, so that the wear resistance is improved, the change with time is small, and the amount of the developer drawn up is small. Maintained for a long time.

  Further, according to the developing device of the present invention described in claim 7, since the developing roller is provided, it is possible to suppress a decrease in the transport amount of the developer due to secular change and to prevent occurrence of image unevenness.

  According to the process cartridge of the eighth aspect, since the developing roller is provided, it is possible to suppress a decrease in the developer conveyance amount due to secular change and to prevent occurrence of image unevenness.

  In addition, according to the image forming apparatus of the ninth aspect, since the developing roller is provided, it is possible to suppress a decrease in the transport amount of the developer due to secular change and to prevent occurrence of image unevenness.

  According to the method for producing a developing roller of the present invention described in claim 10, the cylindrical developing sleeve having a wear-resistant layer on the outer surface and the short wire rod material are accommodated in the same accommodating tank. Then, a rotating magnetic field is generated in the storage tank, the developing sleeve is rotated around its axis, and the linear member is caused to collide with the developing sleeve material while being rotated. Since it has a step of forming a dent on the surface, a uniform dent can be reliably formed at low cost, and a developing sleeve that can suppress secular change can be obtained. By performing the roughening process until the surface is exposed, the wear-resistant layer is not present at the bottom of the dent, so that the dent depth can be secured even if the transport amount is reduced due to deterioration of the developer. Sufficient transport amount is obtained Since the, possible to suppress the deterioration of the conveyance amount.

  Hereinafter, the developing roller according to the present invention will be described with reference to FIGS.

  FIG. 1 is a cross-sectional view of a magnetic particle carrier (developing roller) according to the present invention. FIG. 2 is a perspective view of a hollow body (developing sleeve) that constitutes a magnetic particle carrier according to an embodiment of the present invention. 3 and 4 are model views showing a cross section near the outer surface of the developing sleeve.

  FIG. 5 shows the outer surface of a hollow body having a larger number of dents in a plan view elliptical shape in which the longitudinal direction of the ellipse extends along the axial direction of the hollow body than a dent in a plan view elliptical shape in which the longitudinal direction of the ellipse extends along the circumferential direction of the hollow body. It is explanatory drawing which expands and shows. FIG. 6 is an explanatory view schematically showing the outer surface of the hollow body shown in FIG. FIG. 7 shows the outer surface of a hollow body having many oval-shaped dents in the plan view along the circumferential direction of the hollow body, rather than the oval-shaped dents in the plan view along the axial direction of the hollow body. It is explanatory drawing which expands and shows. FIG. 8 is an explanatory view schematically showing the outer surface of the hollow body shown in FIG. FIG. 9 is a cross-sectional view of the magnetic particle carrier showing the rising state of the developer on the outer surface of the magnetic particle carrier having the hollow body shown in FIG. FIG. 10 is a cross-sectional view of the magnetic particle carrier showing the rising state of the developer on the outer surface of the magnetic particle carrier having the hollow body shown in FIG. FIG. 11 is a model enlarged cross-sectional view of the developing sleeve 132.

  FIG. 12 is a cross-sectional view of the magnetic particles constituting the developer. FIG. 13 is a cross-sectional view of a developing device and a process cartridge showing an embodiment of the present invention. FIG. 14 is a cross-sectional view of an image forming apparatus showing an embodiment of the present invention. FIG. 15 is a perspective view illustrating a schematic configuration of a surface treatment apparatus that performs a roughening process on the outer surface of the hollow body illustrated in FIG. 2. 16 is a cross-sectional view taken along II-II of the surface treatment apparatus shown in FIG. FIG. 17 is a perspective view of a wire rod used in the surface treatment apparatus shown in FIG. 18 is a partially enlarged view of a cross section taken along III-III of the wire rod shown in FIG. FIG. 19 is an explanatory diagram showing a hollow body to be processed in the surface treatment apparatus shown in FIG. 15 and a linear member that rotates and moves along the outer periphery of the hollow body while rotating.

  Next, the configuration of the developing roller according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4, 7, 8, and 11.

  As shown in FIG. 1, the developing roller 115, which is a magnetic particle carrier of the present invention, includes a cored bar 134, a magnetic field generating means (hereinafter referred to as a magnet roller (also referred to as a magnet body)) 133, and a hollow body (hereinafter referred to as a developer). Sleeve) 132. The core bar 134 is arranged in parallel with the longitudinal direction of the photosensitive drum 108 shown in FIG. 12 and is fixed to the case 125 of the developing device 113 without rotating.

  The magnet roller 133 is made of a magnetic material, is formed in a cylindrical shape, and is attached with a plurality of fixed magnetic poles (not shown). The magnet roller 133 is fixed to the outer periphery of the core bar 134 without rotating around the axis.

  The fixed magnetic pole is a long and rod-shaped magnet, and is attached to the magnet roller 133. The fixed magnetic pole extends along the longitudinal direction of the magnet roller 133, that is, the developing roller 115, and is provided over the entire length of the magnet roller 133. The magnet roller 133 having the above-described configuration is accommodated (enclosed) in the developing sleeve 132.

  One fixed magnetic pole is opposed to the stirring screw 118 shown in FIG. 12 as a pumping magnetic pole for pumping up the developer, and the other one fixed magnetic pole is opposed to the photosensitive drum 108 shown in FIG. 12 as a developing magnetic pole. ing. The fixed magnetic pole attracts magnetic particles (hereinafter referred to as magnetic carrier) 135 contained in the developer 126 to the outer surface of the developing sleeve 132, and a plurality of magnetic carriers 135 are stacked along the magnetic field lines generated by the fixed magnetic pole. Thus, the developing sleeve 132 is erected (protruded) on the outer surface. In this manner, a state in which a plurality of magnetic carriers 135 are erected on the outer surface of the developing sleeve 132 along the lines of magnetic force is referred to as the magnetic carrier 135 rising on the outer surface of the developing sleeve 132. As a result, the toner contained in the developer 126 is adsorbed to the magnetic carrier 135 that has grown up. That is, the developing sleeve 132 attracts the developer 126 to the outer surface by the magnetic force of the magnet roller 133.

  As shown in FIG. 2, the developing sleeve 132 is formed in a cylindrical shape. The developing sleeve 132 includes (accommodates) a magnet roller 133 and is provided so as to be rotatable around the axis. The developing sleeve 132 is rotated so that the inner peripheral surface thereof is sequentially opposed to the fixed magnetic pole.

  The sleeve base 132a of the developing sleeve 132 is made of a nonmagnetic material such as an aluminum alloy or stainless steel.

  Aluminum alloys are excellent in terms of workability and lightness. When using an aluminum alloy as a base material, it is preferable to use A6063, A5056, and A3003. On the other hand, stainless steel is superior in terms of wear resistance and strength. When stainless steel is used as the sleeve base material 132a, it is preferable to use SUS303, SUS304, and SUS316.

  Here, the aluminum alloy has a Vickers hardness of about Hv = 60, and the stainless steel has about a Hv = 200. Particularly, the hardness of the aluminum alloy is low, and unevenness gradually decreases due to secular change due to wear. Therefore, surface treatment can be performed on the outer surface of the sleeve base 132a, and first, as shown in FIG. 3A, which is a model cross-sectional view, the surface hardness can be increased by providing the wear-resistant layer 132b. At this time, the wear resistance is improved.

  The wear-resistant layer obtained by the surface treatment preferably has a Picker's hardness: Hv = 300 or more in order to obtain sufficient wear resistance. Such a wear-resistant layer may be formed by nickel plating or chrome plating. When the sleeve base is made of aluminum or an aluminum alloy, conductive alumite treatment is performed according to a conventional method. Also good.

  The nickel layer formed by nickel plating (including nickel phosphorus plating) has a high Picker hardness of about Hv = 500. There are two types of nickel plating: electro nickel plating and electroless nickel plating, but electroless nickel plating is preferred from the viewpoint of adhesion, uniformity, and fewer pinholes in the film than electro nickel plating. By performing heat treatment at 300 ° C. or higher after plating, it is possible to improve the hardness to the same extent as chromium plating. However, since heat treatment becomes magnetic, such heat treatment is not performed. It is preferable.

  Electroless nickel plating methods include Ni-P (electroless nickel plating) and Ni-B (electroless nickel / boron plating), but Ni-P is highly versatile and has high quality stability. It is particularly preferable to carry out.

  The surface treatment layer by chromium plating is very high with Hv = 700 or more, and is excellent in wear resistance. In addition, when an intermediate layer is provided between the base material and the chromium plating layer, it is formed by metal plating. In this case, a nickel plating layer as the intermediate layer can further improve wear resistance and corrosion resistance. This is particularly preferred because it can be done.

  The surface treatment layer made of conductive alumite is as high as Hv = 350 to 500, and is less expensive than other plating treatments. In addition, since it is generated electrochemically from an aluminum alloy as a base material, it has a feature that it is harder to peel than plating, which is advantageous in these respects.

  However, alumite is generally a non-conductor, but after anodizing, as a secondary treatment, electrochemically metal (silver in the product of the present invention) is placed in the countless honeycomb holes (porous) generated on the anodized surface. ) Can be made conductive anodized with sufficiently high conductivity to the alumite. In general, after the metal is deposited in the hole by the secondary treatment, the hole is hydrated with a high-temperature aqueous solution such as nickel acetate or pressurized steam to seal the hole (sealing treatment). In the present invention, it is preferable not to perform this sealing treatment from the viewpoint of ensuring conductivity.

  After the surface of the sleeve is formed with the wear-resistant layer by the surface treatment as described above, the outer surface is roughened by the surface treatment apparatus 1 shown in FIG. At this time, the wear-resistant layer 132b is not present at the bottom of the recess (the state near the sleeve surface at this time is shown in FIG. 3B as a model cross-sectional view), or the wear-resistant layer at the bottom of the recess is A structure that is thinner than the other wear-resistant layers (the state near the sleeve surface at this time is shown in FIG. 3C as a model cross-sectional view) is obtained.

  As shown in FIG. 3B, when there is no wear-resistant layer at the bottom of the dent, as shown in a model in FIG. 4A, when the developer enters the dent, the dent without surface treatment. The bottom part is more easily worn than the surface having the surface treatment layer 5, and as shown in a model in FIG. 4B, the difference in the unevenness of the surface becomes large, and the transport amount is reduced due to the deterioration of the developer. However, since the depth of the dent can be secured and a sufficient transport amount can be obtained, a decrease in the transport amount can be suppressed.

  On the other hand, when the wear-resistant layer at the bottom of the dent is thinner than the other wear-resistant layers as shown in FIG. 3 (c), the initial resistance is shown in FIG. 4 (c). Roughness is not easily lowered by the wearable layer, the wear-resistant layer at the bottom is lost, and when the sleeve base material surface layer appears, the bottom is easily worn, and the state at that time is modeled in FIG. As shown in FIG. 3B, as a result, the same effect as in the case where the wear-resistant layer is not provided at the bottom of the dent may be obtained, but the effect can be surely obtained from the initial stage. As indicated, it is preferred that there is no wear-resistant layer at the bottom of the recess and the sleeve substrate is exposed.

  As the thickness of the wear-resistant layer formed above, it is preferable that the ten-point average roughness Rz of the outer surface of the developing sleeve 132 is 8 μm or more in order to make the effect of the roughening treatment sufficient. At this time, in order to obtain good surface properties, the thickness is preferably 3 μm or more.

  The outer diameter of the developing sleeve 132 is preferably about 17 mm to 18 mm, and the length of the developing sleeve 132 in the axis (axial center) direction is preferably about 240 mm to 350 mm. The surface roughness of the outer surface of the developing sleeve 132 is gradually increased (roughened) from the central portion in the axial direction of the developing sleeve 132 toward both ends. Further, as shown in FIG. 7, the outer surface of the developing sleeve 132 has a lot of dents 139 having an elliptical planar shape (hereinafter simply referred to as an elliptical dent in the plan view). A plurality of dents 139 are arranged so that the longitudinal direction of the ellipse is along the axial direction of the developing sleeve 132 (the angle of the longitudinal direction of the ellipse with respect to the axial direction is less than ± 45 °; hereinafter, a lateral dent) 139a , And a dent along the circumferential direction of the developing sleeve 132 (the angle of the longitudinal direction of the ellipse with respect to the circumferential direction is within ± 45 °; hereinafter referred to as a vertical dent) 139b. And the vertical dent 139b is included more than the horizontal dent 139a. Further, the length (major axis) of the recess 139 in the longitudinal direction is 0.05 mm or more and 2 mm or less, and the width (minor axis) in the width direction is 0.02 mm or more and 1 mm or less. . 7 and 8, the left-right direction in the drawings is the axial direction of the developing sleeve 132, and the up-down direction is the circumferential direction of the developing sleeve 132.

  Next, the operation in which the magnetic particle carrier 115 adsorbs the developer 126 on the outer surface will be described.

  In the developing device 113 shown in FIG. 12, a developing roller 115 as a developer carrying member and a developer 126 composed of a magnetic carrier 135 and toner as magnetic particles face each other with a gap. The pumping magnetic pole attached to the magnet roller 133 included in the developing roller 115 generates a magnetic force on the outer surface of the developing sleeve 132, that is, the developing roller 115, so that the inside of the second space 121 of the storage tank 117 is within the second space 121. The developer 126 is adsorbed on the outer surface of the developing sleeve 132. The developing magnetic pole generates a magnetic force on the developing sleeve 132, that is, the outer surface of the developing roller 115, and forms a magnetic field between the developing sleeve 132 and the photosensitive drum 108. The developing magnetic pole forms a magnetic brush by the magnetic field so that the developer 126 adsorbed on the outer surface of the developing sleeve 132 is transferred to the photosensitive drum 108. At least one fixed magnetic pole is provided between the pumping magnetic pole and the developing magnetic pole. The at least one fixed magnetic pole generates a magnetic force on the outer surface of the developing sleeve 132, that is, the developing roller 115, conveys the developer 126 before development toward the photosensitive drum 108, and develops the developed developer. The agent 126 is conveyed from the photosensitive drum 108 into the storage tank 117.

  Next, an elliptical recess (that is, a lateral recess) 139a in which the longitudinal direction of the ellipse is along the axial direction of the hollow body (ie, the developing sleeve) 132, and an elliptical shape in which the longitudinal direction of the ellipse is along the circumferential direction of the developing sleeve 132 The difference in the rising of the developer from the dent (that is, the vertical dent) 139b will be described.

  FIG. 9 is a cross-sectional view of a conventional magnetic particle carrier 115 and shows the state of the rising of the developer 126 when there are more horizontal dents 139a than vertical dents 139b. FIG. 10 is a cross-sectional view of the magnetic particle carrier 115 according to the present invention, and shows the state of the rising of the developer 126 when the vertical dent 139b is larger than the horizontal dent 139a. Compared with the horizontal dent 139a of the conventional magnetic particle carrier 115 shown in FIG. 9, the vertical dent 139b of the magnetic particle carrier 115 in the present invention shown in FIG. 10 is seen from the cross section of the magnetic particle carrier. The length of the recess 139 along the circumferential direction becomes longer, and the developer 126 adheres closely to the recess 139 and is attracted to the developing sleeve 132, so that the developer is more adsorbed with respect to the circumferential direction of the developing sleeve 132. The density is increased, and the rise of the developer in each recess 139b becomes more uniform.

  From the above description, according to the present embodiment, in the many oval-shaped recesses 139 on the outer surface of the developing sleeve 132, the longitudinal direction is longer than the oval-shaped recesses 139a in plan view along the axial direction of the hollow body. However, since there are many oval-shaped recesses 139b in the plan view along the circumferential direction of the hollow body, the magnetic particle group contained in the developer 126 is uniformly adsorbed in the circumferential direction of the outer surface of the developing sleeve 132. In addition, the density of the magnetic particles in the circumferential direction on the outer surface of the developing sleeve 132 is increased, so that the developer 126 is made uniform with respect to the circumferential direction of the photosensitive drum 108, that is, the sheet passing direction of the image. Therefore, it is possible to supply an image without unevenness, and thus it is possible to obtain an image with no unevenness of density in the sheet passing direction. In addition, the outer surface of the developing sleeve 132 has an elliptical recess 139 larger than the recess formed by conventional sandblasting (the major axis is 0.05 mm or more and 2 mm or less, the minor axis is 0.02 mm or more and 1 mm or less). Therefore, the wear of the oval-shaped dent due to aging is less than that of the dent formed by sandblasting. Therefore, a decrease in the transport amount of the developer 126 due to aging can be suppressed, and thus formed. It is possible to prevent the image from becoming thin.

Further, in a number of oval-shaped recesses 139 on the outer surface of the developing sleeve 132, the deepest portion 200 c of the concave portion 139 with respect to the rotation direction of the developing sleeve 132 is shown in FIG. Therefore, the surface from the deepest portion 200c of the dent to the outer edge end portion 200a of the dent and the straight line in the radial direction of the developing sleeve 132 that passes through the deepest portion 200c of the dent are located. The angle α formed is less than 45 °, so that the dent 139 scoops up the magnetic particles and holds it inside the dent 139, that is, the force to hold the magnetic particles on the outer surface of the developing sleeve 132 becomes strong, and the developer is surely Can be held on the outer surface of the developing sleeve 132, so that a decrease in the transport amount of the developer due to secular change can be suppressed, and the formed image is thin. Can be prevented. Further, since a sufficient holding force can be obtained without increasing the depth of the recess 139, the processing energy of the outer surface of the developing sleeve 132 can be reduced, so that the axis of the developing sleeve 132 is curved. The inner and outer diameters can be prevented from changing and the cross-sectional shape can be prevented from becoming an elliptical shape, that is, the shake accuracy can be kept high, and an image having no image unevenness can be obtained.

  In addition, in a large number of elliptical recesses 139 on the outer surface of the developing sleeve 132, the outer edge end portion 200a of the recess that is rearward with respect to the rotation direction of the developing sleeve 132 is directed outward from the outer surface of the developing sleeve 132. Therefore, the surface from the deepest part 200c of the dent to the outer edge end part 200a is longer and larger, and the force for holding the magnetic particles on the outer surface of the developing sleeve 132 becomes stronger, and the developer is more reliably produced. Can be held on the outer surface of the developing sleeve 132, and therefore, a decrease in the transport amount of the developer due to secular change can be suppressed, and a formed image can be prevented from being thinned. Further, since a sufficient holding force can be obtained without increasing the depth of the recess 139, the processing energy of the outer surface of the developing sleeve 132 can be reduced, so that the axis of the developing sleeve 132 is curved. The inner and outer diameters can be prevented from changing and the cross-sectional shape can be prevented from becoming an elliptical shape, that is, the shake accuracy can be kept high, and an image having no image unevenness can be obtained.

  Further, since the recesses 139 having an elliptical shape in plan view are randomly arranged on the outer surface of the developing sleeve 132, the developer 126 is randomly adsorbed on the outer surface of the developing sleeve 132, that is, outside the developing sleeve 132. The developer 126 is evenly adsorbed over the entire surface, so that the amount of the developer 126 conveyed to the photosensitive drum 108 can be made uniform, and thus an image having no uneven density can be obtained.

  Next, the configuration of the developing device 113 according to the present invention will be described with reference to FIG.

  As shown in FIG. 13, the developing device 113 includes at least a magnetic particle (for example, developer) supply unit 114, a case 125, a developing roller 115 as a magnetic particle carrier, and a regulating blade 116 as a regulating member. ing.

  The developer supply unit 114 includes a storage tank 117 and a pair of stirring screws 118 as stirring members. The storage tank 117 is formed in a box shape having a length substantially equal to that of the photosensitive drum 108. Further, a partition wall 119 extending along the longitudinal direction of the storage tank 117 is provided in the storage tank 117. The partition wall 119 partitions the storage tank 117 into a first space 120 and a second space 121. Moreover, both ends of the first space 120 and the second space 121 communicate with each other.

  The storage tank 117 stores the developer 126 in both the first space 120 and the second space 121. The developer 126 includes toner and a magnetic carrier (also referred to as magnetic particles or magnetic powder, whose cross section is shown in FIG. 12) 135. The toner is appropriately supplied to one end portion of the first space 120 on the side away from the developing roller 115 in the first space 120 and the second space 121. The toner is spherical fine particles produced by an emulsion polymerization method or a suspension polymerization method. The toner may be obtained by pulverizing a lump composed of a synthetic resin in which various dyes or pigments are mixed and dispersed. The average particle diameter of the toner is 3 μm or more and 7 μm or less. The toner may be formed by pulverization or the like.

  The stirring screw 118 is accommodated in each of the first space 120 and the second space 121. The longitudinal direction of the stirring screw 118 is parallel to the longitudinal directions of the storage tank 117, the developing roller 115, and the photosensitive drum 108. The agitating screw 118 is provided so as to be rotatable around an axis, and rotates around the axis to agitate the toner and the magnetic carrier 135 and convey the developer 126 along the axis. Further, the agitation screw 118 in the first space 120 conveys the developer 126 from the above-described one end to the other end. The agitation screw 118 in the second space 121 conveys the developer 126 from the other end toward the one end.

  In the developer supply unit 114, the toner supplied to one end of the first space 120 is conveyed to the other end while stirring with the magnetic carrier 135, and the other end of the second space 121 is transferred from the other end. Transport to. The developer supply unit 114 agitates the toner and the magnetic carrier 135 in the second space 121 and supplies the toner and the magnetic carrier 135 to the outer surface of the developing roller 115 while transporting them in the axial direction.

  The case 125 is formed in a box shape, is attached to the storage tank 117 of the developer supply unit 114 described above, and covers the developing roller 115 and the like together with the storage tank 117. In addition, an opening 125 a is provided in a portion of the case 125 that faces the photosensitive drum 108.

  The developing roller 115 is formed in a cylindrical shape, and is provided between the second space 121 and the photosensitive drum 108 and in the vicinity of the opening 125a described above. The developing roller 115 is parallel to both the photosensitive drum 108 and the storage tank 117. The developing roller 115 is disposed at a distance from the photosensitive drum 108. A space between the developing roller 115 and the photosensitive drum 108 forms a developing region 131 in which the toner of the developer 126 is attracted to the photosensitive drum 108 and the electrostatic latent image is developed to obtain a toner image. In the developing area 131, the developing roller 115 and the photosensitive drum 108 face each other.

  The regulating blade 116 is provided at the end of the developing device 113 near the photosensitive drum 108. The regulating blade 116 is attached to the case 125 described above with a space from the outer surface of the developing sleeve 132. The regulating blade 116 scrapes the developer 126 on the outer surface of the developing sleeve 132 exceeding the desired thickness into the storage tank 117, and the developer 126 on the outer surface of the developing sleeve 132 conveyed to the developing region 131. Adjust the amount.

  Next, an operation in which the developing device 113 conveys the developer 126 to the developing area 131 will be described.

  In the developing device 113 configured as described above, the toner and the magnetic carrier 135 are sufficiently agitated by the developer supplying unit 114, and the agitated developer 126 is fixed to the outer surface of the developing sleeve 132 by a fixed magnetic pole included in the developing roller 115. Adsorb to. Then, the developing device 113 conveys the developer 126 adsorbed by the plurality of fixed magnetic poles toward the developing region 131 as the developing sleeve 132 rotates. The developing device 113 causes the photosensitive drum 108 to adsorb the developer 126 having a desired thickness by the regulating blade 116. In this way, the developing device 113 carries the developer 126 on the developing roller 115, conveys it to the developing area 131, and develops the electrostatic latent image on the photosensitive drum 108 to form a toner image. Then, the developing device 113 causes the developed developer 126 to be released toward the storage tank 117. Further, the developed developer 126 stored in the storage tank 117 is sufficiently agitated with another developer 126 in the second space 121 again, and the electrostatic latent image of the photosensitive drum 108 is Used for development.

  As described above, according to the present invention, since the developing device 113 has the magnetic particle carrier, that is, the developing roller 115, the developer 126 is evenly uneven in the image passing direction. In addition, it is possible to suppress the decrease in the conveyance amount of the developer 126 due to secular change, and thus it is possible to obtain an image without uneven density and to prevent the formed image from becoming thin.

  Next, the structure of the magnetic carrier which is a magnetic particle will be described with reference to FIG.

  The magnetic carrier 135 is accommodated in both the first space 120 and the second space 121 shown in FIG. The average particle diameter of the magnetic carrier 135 is 20 μm or more and 50 μm or less. As shown in FIG. 12, the magnetic carrier 135 includes a core material 136, a resin coat film 137 covering the outer surface of the core material 136, and alumina particles 138 dispersed in the resin coat film 137. .

  If the average particle size of the magnetic carrier 135 is less than 20 μm, the magnitude of the magnetization of each magnetic carrier 135 becomes small, so the magnetic binding force of the magnetic carrier 135 from the developing roller 115 becomes weak, and the magnetic carrier 135 Since the carrier 135 tends to be attracted to the photosensitive drum 108, it is not desirable. If the average particle diameter of the magnetic carrier 135 exceeds 50 μm, the electric field between the magnetic carrier 135 and the electrostatic latent image on the photosensitive drum 108 becomes sparse, and a uniform image cannot be obtained (the image quality deteriorates). Therefore, it is not desirable.

  The core 136 is made of ferrite as a magnetic material and is formed in a spherical shape. The resin coat film 137 covers the entire outer surface of the core material 136. The resin coat film 137 contains a resin component obtained by crosslinking a thermoplastic resin such as acrylic and a melamine resin, and a charge adjusting agent. This resin coat film 137 has elasticity and strong adhesive force. The alumina particles 138 are formed in a spherical shape whose outer diameter is larger than the thickness of the resin coat film 137. The alumina particles 138 are held with a strong adhesive force of the resin coat film 137. The alumina particles 138 protrude from the resin coat film 137 to the outer peripheral side of the magnetic carrier 135.

  From the above description, according to the present invention, the developing device 113 described above uses the developer 126 in which the average particle size of the magnetic particles, that is, the magnetic carrier 135 is 20 μm or more and 50 μm or less. Is excellent in granularity, and thus an excellent image with little unevenness can be obtained.

  Next, the configuration of the process cartridge according to the present invention will be described with reference to FIG.

  The process cartridges 106Y, 106M, 106C, and 106K include a cartridge case 111, a charging roller 109 as a charging device, a photosensitive drum 108 as a photosensitive member (also referred to as an image carrier), and a cleaning blade 112 as a cleaning device. And a developing device 113.

  The cartridge case 111 is detachably attached to the apparatus main body 102 and accommodates a charging roller 109, a photosensitive drum 108, a cleaning blade 112, and a developing device 113. The charging roller 109 uniformly charges the outer surface of the photosensitive drum 108. The photosensitive drum 108 is disposed with a gap from a later-described magnetic particle carrier (for example, a developing roller) 115 of the developing device 113. The photosensitive drum 108 is formed in a columnar shape or a cylindrical shape that is rotatable around an axis.

  The distance between the developing roller 115, that is, the developing sleeve 132 and the photosensitive drum 108 is preferably 0.1 mm or more and 0.4 mm or less. The toner can be reliably supplied to the photosensitive drum 108, and a high-quality image can be obtained. If the distance between the developing sleeve 132 and the photosensitive drum 108 is less than 0.1 mm, the electric field between the developing sleeve 132 and the photosensitive drum 108 becomes too strong, and the magnetic carrier 135 is formed on the photosensitive drum 108. It moves and is not desirable. If the distance between the developing sleeve 132 and the photosensitive drum 108 exceeds 0.4 mm, the electric field between the developing sleeve 132 and the photosensitive drum 108 becomes too weak, and the amount of toner that can be supplied to the photosensitive drum 108 is small. This decreases the development efficiency and increases the edge effect of the electric field at the edge of the image, making it impossible to obtain a uniform image.

  Next, the operation in which the process cartridges 106Y, 106M, 106C, and 106K transfer an image to the recording paper 107 will be described.

  The photosensitive drum 108 in each process cartridge 106 forms an electrostatic latent image on its outer surface by a corresponding laser writing unit 122 shown in FIG. The photosensitive drum 108 is developed by adsorbing the toner supplied from the developing device 113 to the electrostatic latent image formed and carried on the outer surface, and the toner image thus obtained is conveyed between the photosensitive belt 108 and the conveyance belt 129. The image is transferred to the recording paper 107 positioned. The cleaning blade 112 removes the transfer residual toner remaining on the outer surface of the photosensitive drum 108 after the toner image is transferred to the recording paper 107.

  As described above, according to the present invention, since the process cartridge 106 has the developing device 113 described above, the developer 126 can be supplied uniformly and uniformly in the sheet passing direction of the image. A decrease in the transport amount of the developer 126 due to the change can be suppressed, so that an image having no density unevenness can be obtained, and the formed image can be prevented from becoming thin.

  Next, the configuration of the image forming apparatus 101 according to the present invention will be described with reference to FIG.

  The image forming apparatus 101 prints an image of each color of yellow (Y), magenta (M), cyan (C), and black (K), that is, a color image, on a recording sheet 107 (FIG. 14). Formed). The units corresponding to the colors of yellow, magenta, cyan, and black are indicated by adding Y, M, C, and K at the end of the reference numerals.

  As shown in FIG. 14, the image forming apparatus 101 includes an apparatus main body 102, a paper feed unit 103, a registration roller pair 110, a transfer unit 104, a fixing unit 105, a plurality of laser writing units 122, and a plurality of laser writing units 122. Process cartridges 106Y, 106M, 106C, and 106K are provided at least.

  The apparatus main body 102 is formed in a box shape, for example, and is installed on a floor or the like. The apparatus main body 102 accommodates a paper feed unit 103, a registration roller pair 110, a transfer unit 104, a fixing unit 105, a plurality of laser writing units 122, and a plurality of process cartridges 106Y, 106M, 106C, and 106K. Yes.

  The paper feed unit 103 is provided in the lower part of the apparatus main body 102. The paper feed unit 103 includes a paper feed cassette 123 that can accommodate the above-described recording paper 107 in a stacked manner and can be taken in and out of the apparatus main body 102, and a paper feed roller 124. The paper feed roller 124 is pressed against the uppermost recording paper 107 in the paper feed cassette 123. The paper feed roller 124 is used to transfer the above-described uppermost recording paper 107 between a transfer belt 129 (described later) of the transfer unit 104 and a photosensitive drum 108 of a developing device 113 (described later) of the process cartridges 106Y, 106M, 106C, and 106K. Send it in between.

  The registration roller pair 110 is provided in a conveyance path of the recording paper 107 conveyed from the paper supply unit 103 to the transfer unit 104, and includes a pair of rollers 110a and 110b. The registration roller pair 110 sandwiches the recording paper 107 between the pair of rollers 110a and 110b, and the transfer unit 104 and the process cartridges 106Y, 106M, 106C, and 106K at a timing at which the sandwiched recording paper 107 can be superimposed on the toner image. Send out in between.

  The transfer unit 104 is provided above the paper feed unit 103. The transfer unit 104 includes a driving roller 128, a driven roller 12, a conveyance belt 129, and transfer rollers 130Y, 130M, 130C, and 130K. The drive roller 128 is disposed on the downstream side in the conveyance direction of the recording paper 107 and is rotationally driven by a motor or the like as a drive source. The driven roller 12 is rotatably supported by the apparatus main body 102 and is disposed on the upstream side in the conveyance direction of the recording paper 107. The conveyor belt 129 is formed in an endless annular shape and is stretched over both the driving roller 128 and the driven roller 12 described above. The transport belt 129 circulates (endless travel) counterclockwise around the drive roller 128 and the driven roller 12 described above as the drive roller 128 is rotationally driven.

  The transfer rollers 130Y, 130M, 130C, and 130K sandwich the conveyance belt 129 and the recording paper 107 on the conveyance belt 129 between the photosensitive drums 108 of the process cartridges 106Y, 106M, 106C, and 106K, respectively. In the transfer unit 104, the transfer rollers 130Y, 130M, 130C, and 130K press the recording paper 107 fed from the paper supply unit 103 against the outer surface of the photosensitive drum 108 of each process cartridge 106Y, 106M, 106C, and 106K. The toner image on the photosensitive drum 108 is transferred to the recording paper 107. The transfer unit 104 sends the recording paper 107 onto which the toner image is transferred toward the fixing unit 105.

  The fixing unit 105 is provided downstream of the transfer unit 104 in the conveyance direction of the recording paper 107, and includes a pair of rollers 105a and 105b that sandwich the recording paper 107 therebetween. The fixing unit 105 presses and heats the recording paper 107 sent out from the transfer unit 104 between the pair of rollers 105a and 105b, thereby recording the toner image transferred from the photosensitive drum 108 onto the recording paper 107. Fix to paper 107.

  The laser writing unit 122 is attached to the apparatus main body 102. The laser writing unit 122 irradiates the outer surface of the photosensitive drum 108 uniformly charged by a later-described charging roller 109 of the process cartridges 106Y, 106M, 106C, and 106K with laser light to form an electrostatic latent image. .

  The process cartridges 106Y, 106M, 106C, and 106K are provided between the transfer unit 104 and the laser writing unit 122, respectively. The process cartridges 106Y, 106M, 106C, and 106K are detachable from the apparatus main body 102. The process cartridges 106Y, 106M, 106C, and 106K are arranged in parallel along the conveyance direction of the recording paper 107.

  The conveyor belt cleaning device 15 collects residual toner on the conveyor belt 109 and stores it in a toner disposal container through a conveyor path (not shown).

  The secondary transfer roller 16 is for transferring the toner image formed on the conveyance belt 109 to the recording paper 107, and a bias having a reverse sign to that of the toner is applied to attract the toner.

  The paper discharge roller pair 24 is a roller for discharging the recording paper 107 on which the toner image is fixed.

  The toner bottle 31 stores Y, M, C, and K replenishment toners, and from there through a conveyance path (not shown), the toner is supplied to the process cartridges 106Y, 106M, 106C, and 106K for each color by a predetermined replenishment amount. Replenish.

  Next, an operation in which the image forming apparatus 101 forms an image on the recording paper 107 will be described.

  First, the image forming apparatus 101 rotates the photosensitive drum 108 and uniformly charges the outer surface of the photosensitive drum 108 by the charging roller 109. Laser light is irradiated on the outer surface of the photosensitive drum 108 to form an electrostatic latent image on the outer surface of the photosensitive drum 108. When the electrostatic latent image is positioned in the developing area 131, the developer 126 adsorbed on the outer surface of the developing sleeve 132 of the developing device 113 is adsorbed on the outer surface of the photosensitive drum 108, and the electrostatic latent image is developed. Then, a toner image is formed on the outer surface of the photosensitive drum 108. In the image forming apparatus 101, the recording paper 107 conveyed by the paper supply roller 124 of the paper supply unit 103 is transferred to the photosensitive drum 108 of the process cartridges 106Y, 106M, 106C, and 106K and the conveyance belt 129 of the transfer unit 104. The toner image formed on the outer surface of the photosensitive drum 108 is transferred to the recording paper 107. The image forming apparatus 101 uses a fixing unit 105 to fix the toner image on the recording paper 107. Thus, the image forming apparatus 101 forms a color image on the recording paper 107.

  As described above, according to the present invention, since the image forming apparatus 101 includes the developing device 113 described above, the developer 126 can be supplied uniformly and uniformly in the sheet passing direction of the image. It is possible to suppress a decrease in the transport amount of the developer 126 due to secular change, and thus it is possible to obtain an image without density unevenness and to prevent a formed image from becoming thin.

  Next, a surface treatment device for forming an elliptical recess on the outer surface of the hollow body constituting the magnetic particle carrier according to the present invention, and the inner surface of the hollow body enclosed in the surface treatment device. The collided wire rod will be described with reference to FIGS.

  As shown in FIG. 15, the surface treatment apparatus 1 includes a base 3, a fixed holding unit 4, an electromagnetic coil moving unit 5 as a moving unit, a moving holding unit 6, a moving chuck unit 7, and a magnetic field generating unit. The electromagnetic coil 8, the storage tank 9, the collection | recovery part 10, the cooling part 11, the linear encoder 75 as a detection means, and the control apparatus 76 (shown in FIG. 16) as a control means are provided.

  The base 3 is formed in a flat plate shape and is installed on a factory floor or table. The upper surface of the base 3 is kept parallel to the horizontal direction. The planar shape of the base 3 is formed in a rectangular shape.

  The fixed holding portion 4 includes a plurality of support columns 12 erected from one end in the longitudinal direction of the base 3 (hereinafter, indicated by an arrow X), a holding base 13, a standing bracket 14, a cylindrical holding member 15, and a holding member. And a chuck 16.

  The holding base 13 is formed in a flat plate shape and is attached to the upper end of the support column 12. The standing bracket 14 is formed in a flat plate shape and stands from the holding base 13. The cylindrical holding member 15 is formed in a cylindrical shape, and is attached to the standing bracket 14 and the holding base 13. The cylindrical holding member 15 is disposed closer to the center of the base 3 than the upright bracket 14 in a state in which the axis is parallel to both the horizontal direction and the arrow X. The cylindrical holding member 15 accommodates flange members 51b, 51c, 51d (that is, one end portion 9a), which will be described later, attached to one end portion 9a, which will be described later, of the storage tank 9.

  The holding chuck 16 is disposed in the vicinity of the above-described cylindrical holding member 15, that is, the holding base 13, and is attached to the above-described base 3. The holding chuck 16 chucks the storage tank 9 in which the one end 9 a is stored in the cylindrical holding member 15, and holds the one end 9 a of the storage tank 9. The fixed holding portion 4 having the above-described configuration holds the one end portion 9 a of the storage tank 9.

  The electromagnetic coil moving unit 5 includes a pair of linear guides 17, an electromagnetic coil holding base 18, and an electromagnetic coil moving actuator 19. The linear guide 17 includes a rail 20 and a slider 21. The rail 20 is installed on the base 3. The rail 20 is formed in a straight line, and its longitudinal direction is arranged in parallel to the longitudinal direction of the base 3, that is, the arrow X. The slider 21 is supported by the rail 20 so as to be movable along the longitudinal direction of the rail 20, that is, along the arrow X. In the pair of linear guides 17, the rails 20 are arranged at intervals from each other along the width direction of the base 3 (hereinafter, indicated by an arrow Y). Of course, the arrow X and the arrow Y are orthogonal to each other and parallel to the horizontal direction.

  The electromagnetic coil holding base 18 is formed in a flat plate shape and is mounted on the slider 21 described above. The upper surface of the electromagnetic coil holding base 18 is arranged in parallel with the horizontal direction. The electromagnetic coil holding base 18 installs the electromagnetic coil 8 on the surface. The electromagnetic coil moving actuator 19 is attached to the base 3 and slides the electromagnetic coil holding base 18 along the arrow X. The above-described electromagnetic coil moving unit 5 slides the electromagnetic coil holding base 18, that is, the electromagnetic coil 8 along the arrow Y by the electromagnetic coil moving actuator 19. Moreover, the moving speed of the electromagnetic coil 8 by the electromagnetic coil moving part 5 can be changed between 0 mm / second and 300 mm / second. Furthermore, the moving range of the electromagnetic coil 8 of the electromagnetic coil moving part 5 is about 600 mm.

  The movable holding unit 6 includes a pair of linear guides 22, a holding base 23, a first actuator 24, a second actuator 25, a moving base 26, a bearing rotating unit 27, and a holding chuck 28. .

  The linear guide 22 includes a rail 29 and a slider 30. The rail 29 is installed on the base 3. The rail 29 is formed in a straight line, and its longitudinal direction is arranged in parallel with the arrow X, that is, the longitudinal direction of the base 3. The slider 30 is supported by the rail 29 so as to be movable along the longitudinal direction of the rail 29, that is, along the arrow X. In the pair of linear guides 22, rails 29 are arranged at intervals along the arrow Y, that is, the width direction of the base 3.

  The holding base 23 is formed in a flat plate shape and is mounted on the slider 30 described above. The upper surface of the holding base 23 is arranged in parallel with the horizontal direction. The first actuator 24 is attached to the base 3 and slides the holding base 23 described above along the arrow X.

  The second actuator 25 is attached to the holding base 23 and slides the moving base 26 along the arrow Y. The moving base 26 is formed in a flat plate shape, and its upper surface is arranged in parallel with the horizontal direction.

  The bearing rotating unit 27 includes a pair of bearings 31, a hollow holding member 32 as a core shaft, a driving motor 33 as a rotating means, and a chuck cylinder 34. The pair of bearings 31 are arranged on the moving base 26 while being spaced apart from each other along the arrow X. The hollow holding member 32 is made of a magnetic material, is formed in a cylindrical shape, and is supported by the above-described bearing 31 so as to be rotatable around the axis. The hollow holding member 32 has its axis arranged in parallel with the arrow X described above, that is, the axis of the cylindrical holding member 15 of the fixed holding unit 4. The hollow holding member 32 is shaped so as to protrude from the moving base 26 toward the fixed holding portion 4 so that the one end 32 a is located in the storage tank 9, and the other end 32 c is located on the moving base 26. Arranged in the state. As shown in FIG. 16, the hollow holding member 32 is passed through a cylindrical developing sleeve 132. A pulley 35 is fixed to the other end portion 32 c of the hollow holding member 32 positioned on the moving base 26. The pulley 35 is disposed coaxially with the hollow holding member 32.

  The drive motor 33 is installed on the moving base 26, and a pulley 36 is attached to the output shaft thereof. The axis of the output shaft of the drive motor 33 is parallel to the arrow X. An endless timing belt 37 is wound around the pulleys 35 and 36 described above.

  The chuck cylinder 34 includes a cylinder body 38 installed on the moving base 26 and a chuck shaft 39 slidably provided on the cylinder body 38. The chuck shaft 39 is formed in a cylindrical shape, and its longitudinal direction is arranged in parallel with the arrow X. The chuck shaft 39 is accommodated in the hollow holding member 32 and is disposed coaxially with the hollow holding member 32. A plurality of pairs of chuck claws 40 are attached to the chuck shaft 39.

  The pair of chuck claws 40 are attached to the chuck shaft 39 so as to protrude from the outer peripheral surface of the chuck shaft 39 in the outer peripheral direction of the chuck shaft 39. Further, the chuck pawl 40 can protrude from the outer peripheral surface of the hollow holding member 32 toward the outer periphery of the hollow holding member 32. The chuck claws 40 are provided so that the amount of protrusion from the chuck shaft 39 and the hollow holding member 32 can be changed. The plurality of pairs of chuck claws 40 are arranged at intervals along the longitudinal direction of the chuck shaft 39, that is, the arrow X. When the chuck shaft 39 of the chuck cylinder 34 is reduced in the direction approaching the cylinder body 38, the amount of protrusion of the pair of chuck claws 40 from the chuck shaft 39 and the hollow holding member 32 increases.

  In the chuck cylinder 34 described above, when the chuck shaft 39 is reduced to the cylinder body 38, the chuck pawl 40 protrudes further toward the outer periphery of the chuck shaft 39, and the chuck pawl 40 is attached to the outer periphery of the hollow holding member 32. The chuck shaft 39, the hollow holding member 32, and the developing sleeve 132 are fixed by pressing against the inner peripheral surface of the developing sleeve 132. At this time, of course, the chuck shaft 39, the hollow holding member 32, the developing sleeve 132, and the cylindrical member 50 described later, that is, the storage tank 9 are coaxial. Further, by preventing the chuck claw 40 from protruding from the outer periphery of the hollow holding member 32 and not fixing the developing sleeve 132 and the hollow holding member 32, the developing sleeve 132 can be rotated in its circumferential direction, which will be described later. It is rotated around its axis by electromagnetic induction electromotive force generated by the electromagnetic coil 8.

  The chuck cylinder 34 and the chuck pawl 40 described above hold the developing sleeve 132 so as to be coaxial with the hollow holding member 32 and the storage tank 9. That is, the chuck cylinder 34 and the chuck pawl 40 hold the developing sleeve 132 at the center of the storage tank 9.

  The holding chuck 28 is installed on the moving base 26 described above. The holding chuck 28 chucks a flange member 51a (described later) attached to the other end 9b of the storage tank 9, and holds the other end 9b of the storage tank 9. The holding chuck 28 restricts the storage tank 9 from rotating about its axis.

  The movement holding unit 6 having the above-described configuration moves the holding chuck 28, the hollow holding member 32, and the like along the arrows X and Y orthogonal to each other by the actuators 24 and 25. That is, the movement holding unit 6 moves the storage tank 9 held by the holding chuck 28 along the arrows X and Y.

  The moving chuck unit 7 includes a holding base 41, a linear guide 42, and a holding chuck 43. The holding base 41 is fixed to an end portion of the linear guide 22 near the fixed holding portion 4 of the rail 29. The holding base 41 is formed in a flat plate shape, and its upper surface is arranged in parallel with the horizontal direction.

  The linear guide 42 includes a rail 44 and a slider 45. The rail 44 is installed on the holding base 41. The rail 44 is formed in a straight line, and its longitudinal direction is arranged in parallel with the arrow Y, that is, the width direction of the base 3. The slider 45 is supported by the rail 44 so as to be movable along the longitudinal direction of the rail 44, that is, along the arrow Y.

  The holding chuck 43 is installed on the slider 45. The holding chuck 43 is positioned between the holding chucks 16 and 28 described above. The holding chuck 43 holds the storage tank 9 by chucking a portion near the other end 9 b of the storage tank 9. The moving chuck portion 7 described above positions the storage tank 9 by the holding chuck 43 holding the storage tank 9. The movable chuck portion 7 holds the storage tank 9 in cooperation with the above-described holding chuck 28 when the storage tank 9 moves along the axis by holding the storage tank 9 by the holding chuck 43. Thus, the storage tank 9 is prevented from falling off the bearing rotating portion 27, that is, the surface treatment apparatus 1.

  As shown in FIG. 16, the electromagnetic coil 8 includes an outer skin 46 formed in a cylindrical shape and a plurality of coil portions 47 arranged in the outer skin 46, and is formed in an annular shape as a whole. The inner diameter of the electromagnetic coil 8 is larger than the outer diameter of the storage tank 9. That is, a space is formed between the inner peripheral surface of the electromagnetic coil 8 and the outer peripheral surface of the storage tank 9. Further, the total length of the electromagnetic coil 8 in the axial direction is sufficiently shorter than the total length of the storage tank 9 in the axial direction. The total length of the electromagnetic coil 8 in the axial direction is preferably 2/3 or less of the total length of the storage tank 9 in the axial direction. In the illustrated example, the inner diameter of the electromagnetic coil 8 is 90 mm, and the length of the electromagnetic coil 8 in the axial direction is 85 mm.

  The outer skin 46 is attached to the above-described electromagnetic coil holding base 18 with its axis, that is, the axis of the electromagnetic coil 8 itself, parallel to the arrow X. The electromagnetic coil 8 is disposed coaxially with the hollow holding member 32, the chuck shaft 39 and the storage tank 9. The plurality of coil portions 47 are arranged in parallel along the circumferential direction of the outer skin 46, that is, the electromagnetic coil 8. The coil unit 47 is applied by a three-phase AC power supply 48 shown in FIG. The plurality of coil portions 47 are applied with power that is shifted from each other, and the plurality of coil portions 47 generate magnetic fields that are out of phase with each other. And the electromagnetic coil 8 produces | generates the magnetic field (rotating magnetic field) of the rotation direction around the axial center of this electromagnetic coil 8 formed by synthesize | combining these magnetic fields inside.

  The electromagnetic coil 8 described above is applied from a three-phase AC power supply 48 to generate a rotating magnetic field, and is moved by the electromagnetic coil moving unit 5 along the longitudinal direction of its axis, that is, the storage tank 9.

  The electromagnetic coil 8 positions the wire material 65 housed in the housing tank 9 on the outer periphery of the developing sleeve 132 by the rotating magnetic field described above, and the wire material 65 is positioned on the axis of the housing tank 9 and the developing sleeve 132. Rotate (move) around. Then, the electromagnetic coil 8 causes the linear material 65 moved by the above-described rotating magnetic field to collide with the outer surface of the developing sleeve 132.

  Further, an inverter 49 as a magnetic field changing unit is provided between the three-phase AC power supply 48 and the electromagnetic coil 8. That is, the surface treatment apparatus 1 includes an inverter 49 as a magnetic field changing unit. The inverter 49 can freely change the frequency, current value, and voltage value of the power applied to the electromagnetic coil 8 by the three-phase AC power supply 48. The inverter 49 changes the frequency, current value, and voltage value of the power applied to the electromagnetic coil 8 to increase or decrease the power applied to the electromagnetic coil 8 by the three-phase AC power supply 48, thereby generating the electromagnetic coil 8. Change the strength of the rotating magnetic field.

  As shown in FIG. 16, the storage tank 9 has a cylindrical member 50 having a single outer wall (the outer wall is made of a single wall), a plurality of flange members 51, a pair of shaving sealing holders 52, A pair of shavings sealing plates 53, a pair of positioning members 54, a partition member 55 as a plurality of partitioning means, and a pair of sealing plates 56 are provided.

  The cylindrical member 50 is formed in a cylindrical shape and constitutes an outer shell of the storage tank 9. For this reason, the storage tank 9 is formed in a cylindrical shape while the outer wall is formed in a single structure because the cylindrical member 50 is formed in a single structure. The outer diameter of the cylindrical member 50, that is, the storage tank 9, is desirably about 40 mm to 80 mm. Furthermore, the thickness of the cylindrical member 50 is desirably about 0.5 mm to 2.0 mm. The length of the cylindrical member 50 in the axial direction is preferably about 600 mm to 800 mm. The cylindrical member 50 is made of a nonmagnetic material.

  The cylindrical member 50 is provided with a plurality of abrasive grain supply holes 57. Of course, the abrasive grain supply hole 57 passes through the cylindrical member 50 and communicates with the inside and outside of the cylindrical member 50. A sealing cap 58 is attached to the abrasive grain supply hole 57. The abrasive grain supply hole 57 passes the wire material 65 inside, and takes the wire material 65 into and out of the cylindrical member 50, that is, the storage tank 9. The sealing cap 58 closes the abrasive grain supply hole 57 and restricts the filament material 65 from flowing out of the cylindrical member 50, that is, the housing tank 9.

  The plurality of flange members 51 are formed in an annular shape or a cylindrical shape. Most flange members 51 (three in the illustrated example) except for one of the plurality of flange members 51 are attached to one end portion 9a of the cylindrical member 50, and one flange member 51 (hereinafter denoted by reference numeral 51a). ) Is attached to the other end 9 b of the cylindrical member 50.

  One flange member 51 (hereinafter denoted by reference numeral 51 b) among the plurality of flange members 51 attached to the one end 9 a of the cylindrical member 50 is formed in an annular shape and is fitted to the outer periphery of the cylindrical member 50. Yes. Another flange member 51 (hereinafter denoted by reference numeral 51c) is formed in an annular shape and is fitted to the outer periphery of the flange member 51b described above. The remaining flange member 51 (hereinafter denoted by reference numeral 51d) is integrally provided with an annular ring portion 59 and a cylindrical column portion 60. The ring part 59 is standing upright from the outer edge of the cylindrical part 60. As for the flange member 51d, the ring part 59 is fitted to the outer periphery of the flange member 51c.

  A driven shaft 73 is rotatably supported by a bearing 74 on the flange member 51d described above. The driven shaft 73 is formed in a columnar shape and is arranged coaxially with the cylindrical member 50 of the storage tank 9. The hollow holding member 32 is pressed against the end surface of the driven shaft 73. The driven shaft 73 rotates with the hollow holding member 32 and supports one end portion 32 a as a free end of the hollow holding member 32.

  One flange member 51 a described above is formed in an annular shape and is fitted to the outer periphery of the other end portion 9 b of the cylindrical member 50. The flange member 51a passes through the hollow holding member 32 inside. One end 9 a of the cylindrical member 50 forms one end of the storage tank 9, and the other end 9 b of the cylindrical member 50 forms the other end of the storage tank 9.

  Each of the pair of shavings sealing holders 52 is formed in an annular shape. One shaving sealing holder 52 is fitted to the inner circumference of one end 9 a of the cylindrical member 50, and the other shaving sealing holder 52 is fitted to the inner circumference of the other end 9 b of the cylindrical member 50. ing. The other shaving sealing holder 52 passes through the hollow holding member 32 inside.

The pair of shavings sealing plates 53 are each formed in a mesh shape. One shaving sealing plate 53 is formed in a disc shape and is disposed on the inner periphery of the one end portion 9a of the cylindrical member 50, and is attached to the one shaving sealing holder 52 described above. . Furthermore, one shaving sealing plate 53 passes through the driven shaft 73 on the inner side. The other shaving sealing plate 53 is formed in an annular shape, and is disposed on the inner periphery of the other end 9b of the cylindrical member 50, and is attached to the other shaving sealing holder 52 described above. . The other shavings sealing plate 53 passes through the hollow holding member 32 inside. In the shaving sealing plate 53, the filament 65 collides with the outer surface of the developing sleeve 132, and shavings formed by scraping from the developing sleeve 132 leak out of the cylindrical member 50, that is, the storage tank 9. To regulate that.

  The pair of positioning members 54 are formed in a cylindrical shape. One positioning member 54 is fitted to the outer periphery of one end 32 a which is a free end of the hollow holding member 32. The other positioning member 54 is located in the cylindrical member 50 and is fitted to the outer periphery of the central portion 32b of the hollow holding member 32 near the other end portion 9b. The pair of positioning members 54 position the developing sleeve 132 on the hollow holding member 32 with the developing sleeve 132 interposed therebetween. Note that the one end portion 32 a is an end portion of the hollow holding member 32 that is close to the fixed holding portion 4 and away from the moving holding portion 6. The central portion 32 b is on the side inside the storage tank 9 and away from the fixed holding portion of the hollow holding member 32, and forms an end near the moving holding portion 6.

  The partition member 55 includes a main body portion 61 formed in an annular shape and a mesh portion 62.

  The main body 61, that is, the partition member 55 is fitted to the inner periphery of the cylindrical member 50, is attached to the cylindrical member 50, and passes through the hollow holding member 32 inside. The main body 61, that is, the plurality of partition members 55 are arranged between the pair of shavings sealing plates 53. Further, the main body portion 61, that is, the plurality of partition members 55 are arranged in parallel along the axis P of the cylindrical member 50, that is, along the longitudinal direction with a space between each other. In the illustrated example, seven partition members 55 are provided.

  A through-hole 63 is provided in the main body 61. The mesh part 62 is attached to the main body part 61 so as to close the through hole 63. The mesh part 62 is formed in a mesh shape, allows gas and shavings to pass therethrough, and restricts passage of the wire material 65.

  The plurality of partition members 55 described above partition the space in the cylindrical member 50, that is, the storage tank 9, along the axis of the cylindrical member 50, that is, the storage tank 9, that is, the axis P of the developing sleeve 132. In addition, the shaft core P forms both the shaft core of the storage tank 9 and the shaft core of the hollow holding member 32, and the longitudinal direction of the storage tank 9. That is, the axis P and the longitudinal direction of the storage tank 9 are parallel to each other. Furthermore, both the main body portion 61 and the mesh portion 62 described above, that is, the partition member 55 are made of a nonmagnetic material.

  The pair of sealing plates 56 are formed in an annular shape. In addition, the sealing plate 56 is formed in a mesh shape, allows gas and shavings to pass, and restricts passage of the filament material 65. One sealing plate 56 is attached to the partition member 55 closest to the one end 9a, and the other sealing plate 56 is attached to the partition member 55 closest to the other end 9b. The sealing plate 56 passes a cap 64 (described later) attached to both ends of the developing sleeve 132 inside. The sealing plate 56 restricts the passage of the linear member 65 positioned between the partition members 55, and restricts the flow of the linear member 65 to the outside of the cylindrical member 50, that is, the storage tank 9.

  The storage tank 9 configured as described above stores the linear member 65 made of a magnetic material between the plurality of partition members 55, and stores the developing sleeve 132 attached to the hollow holding member 32 in the cylindrical member 50. . That is, the storage tank 9 stores both the developing sleeve 132 and the wire material 65. Further, the linear member 65 collides with the outer surface of the developing sleeve 132 by rotating (moving) the outer periphery of the developing sleeve 132 by the rotating magnetic field described above. The linear member 65 collides with the outer surface of the developing sleeve 132, scrapes a part of the developing sleeve 132 from the outer surface of the developing sleeve 132, and roughens the outer surface of the developing sleeve 132.

  As shown in FIG. 16, the recovery unit 10 includes a gas inflow pipe 66, a gas discharge hole 67, a mesh member 68, a gas discharge duct 69, and a dust collector 70 (shown in FIG. 14). . The gas inflow pipe 66 is provided closer to the end of the cylindrical member 50, that is, the storage tank 9 (moving holding portion 6) than the other shaving sealing holder 52, and opens to the inside of the cylindrical member 50, that is, the storage tank 9. The gas inflow pipe 66 is supplied with pressurized gas or the like from a pressurized gas supply source (not shown). The gas inflow pipe 66 guides the pressurized gas into the cylindrical member 50, that is, the storage tank 9.

  The gas discharge hole 67 penetrates through the cylindrical member 50 and communicates the inside and outside of the storage tank 9, and is closer to the end of the cylindrical member 50, that is, the storage tank 9 than one shaving sealing holder 52 (moving and holding unit). (The side away from 6). The mesh member 68 is attached to the cylindrical member 50 so as to close the gas discharge hole 67. The mesh member 68 allows the shavings and gas to pass therethrough and restricts the passage of the filament material 65. The mesh member 68 restricts the filament material 65 from flowing out of the cylindrical member 50, that is, the outside of the housing tank 9.

  The gas exhaust duct 69 is a pipe and is attached in the vicinity of the gas exhaust hole 67. The gas discharge duct 69 surrounds the outer edge of the gas discharge hole 67. The gas discharge hole 67 and the gas discharge duct 69 guide the gas supplied from the gas inflow pipe 66 into the cylindrical member 50, that is, the storage tank 9, to the outside of the cylindrical member 50, that is, the storage tank 9.

  The dust collector 70 is connected to the gas discharge duct 69 and sucks the gas in the gas discharge duct 69. The dust collector 70 sucks the gas in the gas discharge duct 69 to suck the gas in the cylindrical member 50, that is, the storage tank 9 together with the above-described shavings. The dust collector 70 collects shavings. The recovery unit 10 described above supplies gas into the cylindrical member 50, that is, the storage tank 9 through the gas inflow pipe 66, and the gas and dust collector 70 pass the gas through the gas exhaust hole 67 and the gas exhaust duct 69 to remove the shavings into the cylindrical member. 50, that is, the outside of the storage tank 9. Then, the collection unit 10 collects shavings in the dust collector 70.

  As shown in FIG. 15, the cooling unit 11 includes a cooling fan 71 and a cooling duct 72. The cooling fan 71 supplies the pressurized gas to the cooling duct 72. The cooling duct 72 is a pipe. The cooling duct 72 guides the pressurized gas supplied from the cooling fan 71 to the electromagnetic coil 8. The cooling duct 72 blows the pressurized gas supplied from the cooling fan 71 to the electromagnetic coil 8. The cooling unit 11 cools the electromagnetic coil 8 by blowing a pressurized gas onto the electromagnetic coil 8.

  As shown in FIG. 16, the linear encoder 75 includes a main body 77 and a detector 78 that is movably provided on the main body 77. The main body 77 extends linearly and is attached to the base 3. The main body 77 is disposed between the pair of rails 20 in parallel with the rails 20. The overall length of the main body 77 is longer than the storage tank 9 described above. The main body 77 is disposed at a position where both end portions in the longitudinal direction protrude outward from the housing tank 9 described above along the longitudinal direction of the housing tank 9.

  The detector 78 is provided movably along the longitudinal direction of the main body 77, that is, the storage tank 9. The detector 78 is attached to the electromagnetic coil holding base 18. That is, the detector 78 is attached to the electromagnetic coil 8 via the electromagnetic coil holding base 18.

  The linear encoder 75 described above detects the position of the detector 78 with respect to the main body 77, that is, the storage tank 9, and outputs the detected result toward the control device 76. Thus, the linear encoder 75 detects the relative position of the electromagnetic coil 8 with respect to the storage tank 9, that is, the developing sleeve 132, and outputs the detection result toward the control device 76.

The control device 76 is a computer including a known RAM, ROM, CPU, and the like. The control device 76 is connected to the electromagnetic coil moving unit 5, the movement holding unit 6, the moving chuck unit 7, the electromagnetic coil 8, the inverter 49, the recovery unit 10, the cooling unit 11, the linear encoder 75, and the like. These are controlled to control the entire surface treatment apparatus 1.

  The control device 76 stores the strength of the rotating magnetic field of the electromagnetic coil 8 according to the relative position of the electromagnetic coil 8 detected by the linear encoder 75 with respect to the developing sleeve 132. That is, the control device 76 stores the electric power applied to the electromagnetic coil 8 by the inverter 49 according to the relative position of the electromagnetic coil 8 with respect to the developing sleeve 132. Further, the control device 76 stores the power described above for each product number of the developing sleeve 132.

  In the illustrated example, the control device 76 has a pattern in which the electric power applied by the inverter 49 to the electromagnetic coil 8 gradually increases as the electromagnetic coil 8 moves from the central portion in the longitudinal direction (axial direction) of the developing sleeve 132 toward both ends. Is stored in advance. Then, the control device 76 causes the inverter 49 to change the strength of the rotating magnetic field generated by the electromagnetic coil 8 in accordance with the previously stored power pattern. Thus, in the illustrated example, the control device 76 controls the inverter 49 so that the rotating magnetic field when processing both ends of the developing sleeve 132 is stronger than the rotating magnetic field when processing the central portion of the developing sleeve 132. The strength of the magnetic field generated by the electromagnetic coil 8 is changed. As described above, the control device 76 determines the strength of the rotating magnetic field generated by the electromagnetic coil 8 in the inverter 49 based on the relative position of the electromagnetic coil 8 detected by the linear encoder 75 with respect to the storage tank 9, that is, the developing sleeve 132. To change.

  Further, various input devices such as a keyboard and various display devices such as a display are connected to the control device 76.

  As shown in FIG. 17, the wire material 65 used in the surface treatment apparatus 1 described above is formed in a short linear column shape. The wire rod 65 is made of a magnetic material such as austenitic stainless steel or martensitic stainless steel. Since austenitic stainless steel or martensitic stainless steel is readily available, it is advantageous for reducing the cost of the wire 65.

  The wire rod 65 has an outer diameter of 0.1 mm or more and 2.0 mm or less, and the wire rod 65 has an overall length of L and an outer diameter of D. D is 2 or more and 20 or less. Therefore, the outer edge portions 65 a at both ends in the longitudinal direction of the linear member 65 reliably collide with the developing sleeve 132, and the entire length of the linear member 65 has a sufficient depth (size) on the outer surface of the developing sleeve 132. This is a desirable shape for forming irregularities.

  Furthermore, as shown in FIGS. 17 and 18, the outer edge portions 65 a at both ends of the wire rod 65 are chamfered with a circular arc cross section over the entire circumference. The curvature radius R of the outer edge portion 65a is 0.03 mm or more and 0.5 mm or less. Therefore, this shape is desirable for forming smooth irregularities on the outer surface of the object to be processed.

  As shown in FIG. 19, the wire rod 65 described above is rotated around the center in the longitudinal direction by the rotating magnetic field as shown in FIG. The sleeve 132 is rotationally moved along the circumferential direction of the sleeve 132.

  Next, a process of manufacturing the developing sleeve 132 by processing (roughening) the outer surface of the developing sleeve 132 using the surface processing apparatus 1 having the above-described configuration will be described below.

  First, the product number of the developing sleeve 132 and the like are input to the control device 76 from the input device. Then, cylindrical caps 64 are fitted to the outer circumferences at both ends in the longitudinal direction (axial direction) of the developing sleeve 132. Then, the other positioning member 54 described above is fitted to the outer periphery of the hollow holding member 32. Then, the hollow holding member 32 is passed through the developing sleeve 132 having caps 64 attached to both ends. Thereafter, the one positioning member 54 described above is fitted to the outer periphery of the hollow holding member 32. In this example, the chuck shaft 39 of the chuck cylinder 34 is not reduced, and the developing sleeve 132 is not fixed to the hollow holding member 32, and the developing sleeve 132 is rotatable in the circumferential direction around the shaft. To do. At this time, the clearance between the developing sleeve 132 and the hollow holding member 32 is a few millimeters or less, and the hollow holding member 32 and the developing sleeve 132 are coaxial. In this way, the developing sleeve 132 is attached to the hollow holding member 32.

  The developing sleeve 132 and the hollow holding member 32 are housed in the housing tank 9, and the filament material 65 is supplied into the cylindrical member 50 of the housing tank 9. Thus, the wire 65 and the developing sleeve 132 are accommodated in the accommodating tank 9. Further, the storage tank 9 is chucked by the holding chucks 28 and 43. In this way, the developing sleeve 132 and the storage tank 9 are attached to the movable holding unit 6. Then, the cylindrical member 50, the hollow holding member 32, the developing sleeve 132, and the like of the storage tank 9 become coaxial.

  Of course, the above-described operation is performed while adjusting the position of the moving base 26 with the actuators 24 and 25. Furthermore, the above-described operation is, of course, performed while adjusting the position of the holding base 41. The holding chuck 16 causes the one end 9a of the storage tank 9 to be chucked, for example, so that the fixed holding section 4 holds the one end 9a of the storage tank 9.

  And while supplying gas in the storage tank 9 through the gas inflow pipe 66 of the collection | recovery part 10, while attracting | sucking the gas in the storage tank 9 with the dust collector 70, the gas pressurized by the cooling part 11 is made into the electromagnetic coil 8. Let spray.

  Then, electric power from the three-phase AC power supply 48 is applied to the electromagnetic coil 8 to generate a rotating magnetic field having a frequency of 200 Hz or more in the electromagnetic coil 8. Then, an eddy current is generated in the developing sleeve 132 due to the rotating magnetic field generated in the electromagnetic coil 8, and the developing sleeve 132 rotates at a rotational speed corresponding to the frequency of the rotating magnetic field due to the electromagnetic induction electromotive force generated by the eddy current and the rotating magnetic field. To do. Further, the wire 65 located inside the electromagnetic coil 8 revolves (rotates or moves) around the axis P while rotating, and the wire 65 collides with the outer surface of the developing sleeve 132, The outer surface of the developing sleeve 132 is roughened.

  And the electromagnetic coil moving part 5 moves the electromagnetic coil 8 along the axial core P suitably. Then, the wire rod 65 that has entered the inside of the electromagnetic coil 8 moves (spins and revolves) by the rotating magnetic field described above, and the wire rod 65 that has come out of the inside of the electromagnetic coil 8 stops. Moreover, since the partition member 55 partitions the space in the storage tank 9, the wire member 65 is restricted from moving beyond the partition member 55, and the wire member 65 that has come out from the inside of the electromagnetic coil 8 is described above. Will escape from the rotating magnetic field. Further, when the electromagnetic coil moving unit 5 reciprocates the electromagnetic coil 8 a predetermined number of times along the arrow X, the roughening of the outer surface of the developing sleeve 132 ends.

  Further, the rotating magnetic field generated by the electromagnetic coil 8 becomes stronger as the electromagnetic coil 8 moves from the central portion of the developing sleeve 132 toward both ends. As the rotating magnetic field becomes stronger, the movement of the filament material 65 becomes more intense. Then, as the rotating magnetic field becomes stronger, the wire rod 65 collides with the object to be processed more vigorously, and the surface roughness of the outer surface of the developing sleeve 132 becomes more rough.

  When the above-described roughening of the outer surface of the developing sleeve 132 is completed, the application of electric power to the electromagnetic coil 8 is stopped. Further, the recovery unit 10 and the cooling unit 11 are stopped. Then, the holding tank 16 of the holding chuck 16 of the fixed holding unit 4 is released from holding, and the holding chuck 43 of the moving chuck unit 7 and the holding chuck 28 of the moving holding unit 6 hold the holding tank 9 while holding the holding tank 9. The moving base 26 is separated from the fixed holding portion 4 along the arrow X by the actuator 24. Then, the storage tank 9 is separated from the fixed holding part 4. Then, the developing sleeve 132 whose outer surface has been roughened is taken out of the storage tank 9, and a new developing sleeve 132 is stored in the storage tank 9. Thus, the developing sleeve 132 (shown in FIG. 2) is obtained in which the outer surface of the developing sleeve 132 is roughened, and the surface roughness of the outer surface gradually increases from the central portion toward both ends.

  Further, when the surface treatment apparatus 1 is used to roughen the outer surface of the developing sleeve 132, an eddy current is generated in the developing sleeve 132 due to the rotating magnetic field generated in the electromagnetic coil 8, and this eddy current and rotation are generated. Due to the electromagnetically induced electromotive force generated by the magnetic field, the developing sleeve 132 rotates at a rotational speed corresponding to the frequency of the rotating magnetic field. Further, as shown in FIG. 19, the wire 65 is rotated around the central portion in the longitudinal direction by the rotating magnetic field described above with the longitudinal direction along the radial direction of the storage tank 9 and the developing sleeve 132. The developing sleeve 132 is rotated along the circumferential direction. The rotation speed of the wire 65 at this time corresponds to the frequency of the rotating magnetic field. Since the rotation direction of the linear member 65 and the rotation direction of the developing sleeve 132 are the same, as shown in FIG. 19, the relative speed when the outer edge portion 65a of the linear member 65 collides with the developing sleeve 132 is 2 of the frequency. It is proportional to the power. Therefore, as the frequency of the rotating magnetic field increases, the relative speed increases, and the size of the recess on the outer surface generated by the collision of the filament material 65 per unit time increases in the circumferential direction of the developing sleeve 132. The longitudinal direction of the recess on the outer surface of the developing sleeve 132 is along the circumferential direction. In addition, since the impact force of the outer edge portion 65a of the wire rod 65 increases in proportion to the relative speed, the outer edge portion 65a of the wire rod 65 scoops out the outer surface of the developing sleeve 132 when the relative speed is sufficiently large. Rotate like so. Since most of the wire rods 65 move as shown in FIG. 19, the majority of the elliptical depressions formed on the outer surface of the developing sleeve 132 are such that the longitudinal direction of the ellipse is the circumferential direction of the developing sleeve 132. It becomes a dent along.

  Hereinafter, the present invention will be described more specifically with reference to examples thereof.

Example 1
Wire rod 65 (outer diameter 0.8 mm, length 5 mm, material SUS304) is subjected to nickel phosphorus (Ni-P) plating on the surface of the developing sleeve base made of outer diameter 18 mm, total length 240 mm, material aluminum alloy A6063, A wear-resistant layer having a thickness of 8.2 μm was provided.

  Next, when the surface treatment apparatus 1 described above was used to roughen the outer surface of the developing sleeve base material provided with the wear-resistant layer on the outer surface, a rough surface with Rz = 12.1 μm was obtained. It was. The current value and frequency of the power applied to the electromagnetic coil 8 of the surface treatment apparatus 1 at that time are a current 20A and a frequency 300Hz, respectively, a processing time 30 seconds, and a wire material amount 50g. At this time, the wear-resistant layer at the bottom of the dent was completely removed, and the thickness of the wear-resistant layer in the portion having no dent was 4.7 μm.

(Example 2)
A developing sleeve was prepared in the same manner as in Example 1. The plating conditions at that time were changed to form a 14.2 μm thick wear-resistant layer, and then a roughening treatment was performed. As a result, a rough surface with Rz = 10.8 μm was obtained. The current value and frequency of the power applied to the electromagnetic coil 8 of the surface treatment apparatus 1 were a current of 20 A and a frequency of 300 Hz, respectively, the processing time was 30 seconds, and the amount of wire rod was 50 g. At this time, the bottom of the dent is covered with the wear-resistant layer, and the thickness of the wear-resistant layer at the bottom of the dent (3.7 μm) is set to the thickness of the other part without the dent (11.1 μm). It became thinner than that.

(Example 3)
The surface of the same developing sleeve substrate as used in the examples was subjected to chrome plating, and a wear-resistant layer having a thickness of 6.6 μm was provided.

  Next, on the outer surface of the developing sleeve base material provided with the wear-resistant layer on the outer surface, the current value of the electric power applied to the electromagnetic coil 8 of the surface treatment apparatus 1 is 25 A and the frequency is the same as in Example 1. The surface was roughened at 300 Hz, with a processing time of 30 seconds and a wire material amount of 50 g. At this time, the wear-resistant layer at the bottom of the dent was completely removed, and the thickness of the wear-resistant layer in the non-depressed portion of the developing sleeve was 3.7 μm.

Example 4
As in Example 3, except that a chrome plating treatment was performed to provide a wear-resistant layer having a thickness of 12.7 μm, and then the current value of power applied to the electromagnetic coil 8 of the surface treatment apparatus 1 was 25 A, and the frequency was When roughening was performed at 350 Hz, the processing time was 30 seconds, and the amount of filament material was 50 g, a rough surface with Rz = 9.8 μm was obtained. At this time, the bottom of the dent is covered with the wear-resistant layer, and the thickness of the wear-resistant layer at the bottom of the dent (3.4 μm) is set to the thickness of the other part without the dent (10.1 μm). It became thinner than that.

(Example 5)
The surface of the same developing sleeve substrate as used in Example 1 was first subjected to nickel phosphorous plating as an intermediate layer and then subjected to chrome plating, and the wear-resistant layer having a thickness of 8.1 μm (nickel layer: 6.1 μm, chromium) Layer: 2.0 μm).

  Next, the current value of the power applied to the electromagnetic coil 8 of the surface treatment device 1 is applied to the outer surface of the developing sleeve base material provided with the wear resistant layer on the outer surface in the same manner as described above by the surface treatment device 1 described above. Was 25 A, the frequency was 350 Hz, the processing time was 30 seconds, and the amount of the filament material was 50 g. A rough surface with Rz = 10.4 μm was obtained. At this time, the wear-resistant layer at the bottom of the dent was completely removed, and the thickness of the wear-resistant layer in the non-depressed portion of the developing sleeve was 3.5 μm.

(Example 6)
As in Example 5, first, nickel phosphorous plating was applied as an intermediate layer, followed by chromium plating, and a wear-resistant layer (nickel layer: 9.0 μm, chromium layer: 2.9 μm) having a thickness of 11.9 μm was provided. Then, the surface of the surface treatment apparatus 1 was subjected to a surface roughening treatment with a current of 25 A, a frequency of 350 Hz, a processing time of 30 seconds, and a wire material amount of 50 g, Rz = A rough surface of 9.8 μm was obtained. At this time, the bottom of the dent was covered with the wear-resistant layer, and the thickness of the wear-resistant layer (3.3 μm) was thinner than the thickness of the other parts (9.1 μm).

(Example 7)
The surface of the same developing sleeve base as used in Example 1 was subjected to conductive alumite treatment using a conductive alumite treatment agent kit manufactured by Kunieda Mark Manufacturing Co., Ltd. to provide a wear-resistant layer having a thickness of 6.9 μm. It was.

  Next, on the outer surface of the developing sleeve base material provided with the wear-resistant layer on the outer surface, the current value of the electric power applied to the electromagnetic coil 8 of the surface treatment apparatus 1 is 25 A and the frequency is the same as in Example 1. When a surface roughening treatment was performed at 300 Hz, a processing time of 30 seconds, and a wire material amount of 50 g, a rough surface with Rz = 10.8 μm was obtained. At this time, the wear-resistant layer at the bottom of the dent was completely removed, and the thickness of the wear-resistant layer in the non-depressed portion of the developing sleeve was 3.6 μm.

(Example 8)
As in Example 7, a conductive alumite treatment was performed to provide a wear-resistant layer having a thickness of 11.7 μm, and then the current value of power applied to the electromagnetic coil 8 of the surface treatment apparatus 1 was 25 A, and the frequency was 350 Hz. When the roughening treatment was performed with a processing time of 30 seconds and a wire material amount of 50 g, a rough surface with Rz = 9.5 μm was obtained. At this time, the bottom of the dent is covered with the wear-resistant layer, and the thickness (3.4 μm) of the wear-resistant layer at the bottom of the dent is the thickness of the other part without the dent (10.5 μm). It became thinner than that.

(Comparative Example 1)
The same surface of the developing sleeve as in Example 1 was subjected to sandblasting using alumina abrasive grains having an average particle diameter of 512 μm. At this time, a rough surface having a roughness Rz = 14.5 μm was obtained. Sandblasting conditions were an injection pressure of 4 kgf / cm2 (3.9 × 105 Pa) and a treatment time of 30 seconds.

(Comparative Example 2)
A V-shaped groove having a width of 0.1 mm and a depth of 0.2 mm was machined on the same surface of the developing sleeve base as in Example 1.

(Comparative Example 3)
On the same surface of the developing sleeve substrate as that used in Example 1, the surface treatment apparatus 1 accommodates the wire material 65 (outer diameter 0.8 mm, length 5 mm, material SUS304). When the current value of the electric power applied to the electromagnetic coil 8 is 20 A, the frequency is 300 Hz, the processing time is 30 seconds, and the amount of the line material is 50 g, a rough surface is obtained with Rz = 14.1 μm. It was.

  Using the developing sleeves of the above examples and comparative examples, the following tests were conducted and evaluated.

  A developing sleeve which has been subjected to various roughening processes as described above is attached to a printer (trade name: IPSIO MP C4500 (manufactured by Ricoh Co., Ltd.)) which is a general image forming apparatus, and 620 V on the photosensitive drum. 620 V is applied as a developing bias voltage, a cyan two-component developer (carrier average particle size 35 μm) is used as the developer, the pumping amount is set to 40 mg / cm 2, and a solid image of 195 mm × 285 mm is obtained. 25,000 sheets were output, and the sensory evaluation was performed on the density unevenness in the sheet passing direction of the image in the initial state, after the output of 25000 sheets, and after the output of 500000 sheets.

Evaluation criteria are:
○: The density in the paper passing direction is uniform and the density unevenness is not visually recognized. Δ: The density unevenness in the paper passing direction is slightly visible, but there is no problem in actual use. ×: The density unevenness in the paper passing direction is visually recognized. The results of evaluation are shown in the following Table 1, assuming that they cannot be used. Further, in the developing sleeve surfaces of Examples 1 to 6 and Comparative Example 3 subjected to the roughening treatment by the surface treatment apparatus 1, the longitudinal direction of the ellipse per unit area is a dent along the circumferential direction of the developing sleeve (that is, The ratio (%) of (longitudinal dents) is also shown in Table 1.

  Further, Table 2 shows the change rate of the surface roughness Rz.

  According to Table 1, particularly excellent durability is obtained when the developing roller according to the present invention is used, as compared with the case where the developing roller including the developing sleeve subjected only to the roughening treatment according to the comparative example is used. It can be seen that

  Further, according to Table 2, it can be seen that the roughness of the developing sleeve of the present invention is not reduced by use and the roughness is maintained.

  Further, in the developing sleeves of Examples 1, 3, 5, and 7 in which the sleeve base material is exposed at the bottom of the oval-shaped recess and in the vicinity of the bottom, the sleeve base material is not exposed. It can also be seen that the increase in roughness is large and the margin of roughness is high compared to the development sleeves of 2, 4, 6, and 8.

  In the image forming apparatus 101 described above, the process cartridges 106Y, 106M, 106C, and 106K include a cartridge case 111, a charging roller 109, a photosensitive drum 108, a cleaning blade 112, and a developing device 113. However, in the present invention, the process cartridges 106Y, 106M, 106C, and 106K need only include at least the developing device 113, and do not necessarily include the cartridge case 111, the charging roller 109, the photosensitive drum 108, and the cleaning blade 112. . In the above-described embodiment, the image forming apparatus 101 includes the process cartridges 106Y, 106M, 106C, and 106K that are detachable from the apparatus main body 102. However, in the present invention, the image forming apparatus 101 only needs to include the developing device 113 and does not necessarily include the process cartridges 106Y, 106M, 106C, and 106K.

  In the above-described embodiment, the outer diameter of the developing sleeve 132, the size of the wire 65, and the outer diameter of the cylindrical member 50 of the storage tank 9 included in the surface treatment apparatus 1 may be appropriately changed. It is. In addition, regarding the shape of both ends of the developing sleeve 132, the target surface roughness, processing time (processing conditions), the number of reciprocations of the electromagnetic coil 8, and the filaments are also set such as the radius of curvature of chamfering and the size of the chamfering shape. It is desirable to select an appropriate shape from the durability of the material 65 and the like. Moreover, the total amount of the wire rod 65 accommodated in the storage tank 9 is also appropriate from the target roughness of the rough surface, the processing time (processing conditions), the number of reciprocations of the electromagnetic coil 8, the durability of the wire rod 65, and the like. It is desirable that the amount be determined in a proper amount.

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, various modifications can be made without departing from the scope of the present invention.

It is sectional drawing of the magnetic particle carrier (developing roller) which shows one Embodiment of this invention. It is a perspective view of the hollow body (developing sleeve) which constitutes the magnetic particle carrier which shows one embodiment of the present invention. FIG. 3 is a model cross-sectional view of the vicinity of an outer surface of a developing sleeve constituting the developing roller of the present invention. (A) It is a model figure which shows the state which formed the abrasion resistant layer in the sleeve raw material. (B) It is a model figure which shows the state without an abrasion-resistant layer in the bottom part of a dent. (C) It is a model figure which shows the state where the abrasion-resistant layer of the bottom part of a dent is thin compared with the abrasion-resistant layer of another part. FIG. 3 is a model cross-sectional view of the vicinity of an outer surface of a developing sleeve constituting the developing roller of the present invention. (A) It is a model figure which shows the use condition in the state without an abrasion-resistant layer in the bottom part of a dent (initial use start). (B) It is a model figure which shows the use condition in the state without an abrasion-resistant layer in the bottom part of a dent (after a long-term use). (C) It is a model figure which shows the use condition in the state which does not have an abrasion-resistant layer in the bottom part of a dent (initial use start). (D) It is a model figure which shows the use condition in the state without an abrasion-resistant layer in the bottom part of a dent (after a long-term use). It is explanatory drawing which expands and shows the outer surface of a hollow body with many elliptical dents where the longitudinal direction of an ellipse follows the axial direction of a hollow body rather than the elliptical dent where the longitudinal direction of an ellipse follows the circumferential direction of a hollow body is there. It is explanatory drawing which shows typically the outer surface of the hollow body shown by FIG. It is explanatory drawing which expands and shows the outer surface of a hollow body with many elliptical dents where the longitudinal direction of an ellipse follows the circumferential direction of a hollow body rather than the elliptical dent where the longitudinal direction of an ellipse follows the axial direction of a hollow body is there. It is explanatory drawing which shows typically the outer surface of the hollow body shown by FIG. FIG. 6 is a cross-sectional view of the magnetic particle carrier showing the rising state of the developer on the outer surface of the magnetic particle carrier having the hollow body shown in FIG. 5. FIG. 8 is a cross-sectional view of the magnetic particle carrier showing a rising state of the developer on the outer surface of the magnetic particle carrier having the hollow body shown in FIG. 7. 2 is an enlarged cross-sectional view of a model of a developing sleeve 132. FIG. It is sectional drawing of the magnetic particle which comprises a developing agent. 1 is a cross-sectional view of a developing device and a process cartridge showing an embodiment of the present invention. 1 is a cross-sectional view of an image forming apparatus showing an embodiment of the present invention. It is a perspective view which shows the schematic structure of the surface treatment apparatus which performs a roughening process on the outer surface of the hollow body shown by FIG. It is sectional drawing which follows II-II of the surface treatment apparatus shown in FIG. It is a perspective view of the wire rod used with the surface treatment apparatus shown in FIG. It is the elements on larger scale of the cross section which follows III-III of the wire rod shown in FIG. It is explanatory drawing which shows the filament processed to rotate along the outer periphery of the said hollow body, rotating with the hollow body processed in the surface treatment apparatus shown in FIG. (A) It is model sectional drawing near the outer surface of the developing sleeve which concerns on a prior art (just after a use start). (B) It is model sectional drawing near the outer surface of the image development sleeve concerning a prior art (after a long-term use). (C) It is model sectional drawing near the outer surface of the developing sleeve which concerns on a prior art (V groove processing) (after a long-term use). It is a model figure which shows the secular change of the shape of a developing agent.

Explanation of symbols

65 Wire material 101 Image forming device 106Y, 106M, 106C, 106K Process cartridge 113 Developing device 115 Magnetic particle carrier (developing roller)
132 Hollow body (Development sleeve)
132a Sleeve base material 132b Abrasion resistant layer 133 Magnetic field generating means (magnet roller)
135 Magnetic particles (magnetic carriers)
139 dent 139a dent whose longitudinal direction is along the axial direction of the hollow body (lateral dent)
139b A dent (longitudinal dent) in which the longitudinal direction of the ellipse is along the circumferential direction of the hollow body

Claims (10)

In a developing roller having a magnet roller and a developing sleeve that encloses the magnet roller and attracts magnetic particles to the outer surface by the magnetic force of the magnet roller,
A wear-resistant layer made of a material harder than the material constituting the sleeve base is provided on the outer surface of the sleeve base in the developing sleeve, and an elliptical recess is randomly formed in the wear-resistant layer. A developing roller characterized in that the developing roller is provided.   The developing roller according to claim 1, wherein the sleeve base material is exposed at a bottom portion of the elliptical recess and a portion near the bottom portion. The sleeve base has a cylindrical shape, and
The elliptical dents are more elliptical dents in which the longitudinal direction of the ellipse is along the circumferential direction of the sleeve base material than the elliptical dents in which the longitudinal direction of the ellipse is along the axial direction of the sleeve base material. The developing roller according to claim 1, wherein the developing roller is included.   The said sleeve base material is comprised by aluminum or aluminum alloy, and the said abrasion-resistant layer is comprised by the electroconductive alumite, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Development roller.   The developing roller according to any one of claims 1 to 3, wherein the wear-resistant layer is made of nickel.   The developing roller according to claim 1, wherein the wear-resistant layer is made of chromium.   A developing device comprising the developing roller according to any one of claims 1 to 6.   A process cartridge comprising the developing device according to claim 7.   An image forming apparatus comprising the developing device according to claim 7.   After a cylindrical developing sleeve having a wear-resistant layer on the outer surface and a short wire rod material are accommodated in the accommodating tank, a rotating magnetic field is generated in the accommodating tank, and the developing sleeve is pivoted on its axis. 6. A dent is formed on the outer surface of the developing sleeve by rotating the filament around the core and causing the developing sleeve material to collide while rotating the filament material. A method for producing a developing roller according to any one of the above.