JPH085341A - Method for measuring shape of cylindrical electrophotographic body - Google Patents

Abstract

PURPOSE:To accurately measure a shape such as the roundness, cylindricalness, and deflection of a sensitized body by holding a flange engaged to open parts at both edges of a cylindrical electrophotographic body with a securing pin. CONSTITUTION:A flange part 7A with a recessed rotary center shaft part engaged to open parts at both edges of a cylindrical electrophotographic body (photosensitive drum) 8 is held by two securing pins with a projecting part corresponding to the recessed rotary center shaft part of the flange 7A. At the same time, laser beams are applied while rotating the drum 8 by a drive means in contact with the outer-periphery part of the flange 7A, thus measuring the outer diameter, deflection, straightness, and roundness of the drum. A device with a structure for transferring a smooth rotary drive to the drum 8 is used by allowing the outer-periphery surface of, for example, a cylindrical or disk- shaped rotator as a method for rotating the drum 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow cylindrical drum (hereinafter referred to as a photosensitive drum) provided with a photosensitive coating film used in an electrophotographic apparatus such as a copying machine or a laser beam printer, at both open ends. The present invention relates to a method for reliably and effectively measuring the shape of a cylindrical electrophotographic photosensitive member fitted with a gear component (hereinafter referred to as a flange) for the purpose of receiving rotational drive from the outside.

[0002]

2. Description of the Related Art In an electrophotographic copying machine or a laser beam printer, copying and printing are performed through charges on a photosensitive layer formed on the outer peripheral surface of a hollow cylindrical drum made of metal such as aluminum. By selectively irradiating the photosensitive layer on the outer peripheral surface of the photosensitive drum, which is charged in advance with a specified potential, with light or laser light to cause photodischarge, an electrostatic latent image can be formed on the irradiated portion. By the electric field of the electrostatic latent image, the charged colored particles are attached to the surface of the photosensitive drum, and the particles are transferred and fixed on the transfer paper by Coulomb force, so that the developed image can be copied onto the transfer paper. After that, a series of development processes can be repeated by removing excess colored particles adhering to the outer peripheral surface of the drum and further eliminating the charge on the outer peripheral surface of the drum.

In ordinary copying and printing, gear parts (hereinafter referred to as flanges) intended to transmit rotational drive from the outside are fitted to both open ends of a hollow cylindrical drum. It is performed by repeatedly rotating. If the rotation of the photoconductor is uneven, or if the outer diameter is not constant, the photoconductor is arranged so as to be electrically attached to the outer peripheral surface of the photoconductor and a position facing the outer peripheral surface of the photoconductor. A phenomenon occurs in which the distance from the charged colored particles is partially different, and a large amount of the colored particles adhere to the portion where the distance is short, and the adhesion decreases when the distance is long. When the coloring particles are transferred onto the transfer paper in this state, unevenness in the light and shade of the photoconductor in the rotation cycle occurs in the developed image. Therefore, it is a basic specification that the roundness, straightness, cylindricity, and shake of the photoconductor are small.

As these shape accuracy measuring methods and measuring apparatuses, for example, a measuring apparatus applying the method disclosed in Japanese Patent Laid-Open No. 62-147306, in which the photosensitive drum before fitting the flange is accurately measured Rotate well, and with the knife edge placed parallel to the horizontal base axis, irradiate a parallel scanning light beam such as laser light and block the parallel scanning light beam passing between the photosensitive drum and the knife edge or the measurement object. There is known a device (hereinafter, referred to as a non-contact type shape measuring device) for photoelectrically converting the formed shadow and measuring the gap size.
This device is generally used because it has the advantage of not damaging the surface of the photoreceptor. Examples of commercially available products of the measuring device include an optical outer diameter measuring device manufactured by Keyence Corporation, a laser scan micrometer manufactured by Mitutoyo Corporation, and a laser micrometer manufactured by OMRON Corporation.

As a device for rotating a cylindrical electrophotographic photosensitive member having flanges fitted to both ends of a photosensitive drum, generally, the device is installed in an image forming apparatus and is rotated in accordance with the state of rotation. The photosensitive drum was supported by penetrating a metal cylindrical rod (hereinafter, referred to as a shaft), which has a constant diameter and a small deflection, through the center axis of rotation of the fitted flange over its entire length. In this state, it is common to rotate the shaft while supporting it by mounting it on a mounting table equipped with a mechanism for rotating the shaft.

[0006]

A flange used for a cylindrical electrophotographic photosensitive member generally has a surface of the photosensitive layer which is exposed to light when a photosensitive layer on the outer peripheral surface of the photosensitive member is irradiated with light or laser light. In order to let the electric charge of a part escape to the image forming apparatus, a metal component (hereinafter, referred to as a ground component) capable of electrically conducting is attached. Various methods have been proposed for the shape and mounting method of the grounding component. For example, as disclosed in Japanese Utility Model Laid-Open No. 62-49175, a concave rotary shaft portion that closes the rotation center axis of the flange. In this case, it becomes impossible to penetrate the shaft, and the photosensitive drum rotating device described above cannot support the photosensitive member, so that rotational drive cannot be applied. Further, in general, when the conduction is performed by the above method, since the inner diameter of the central shaft is set on the reference surface of the shape accuracy reference of the photoconductor, it is necessary to support it accurately with this as a reference. .

The problem to be solved by the present invention is to provide the photosensitive member with a shape such as a roundness, a straightness, a cylindricity, and a shake while applying a constant rotational drive while accurately supporting the photosensitive member. It is an object of the present invention to provide a method for measuring the shape of a cylindrical electrophotographic photosensitive member, which is capable of measuring with high accuracy.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a flange having a concave rotation center shaft portion fitted in open portions at both ends of a cylindrical electrophotographic photosensitive member. By gripping with two fixing pins having a convex portion corresponding to the shaft portion and irradiating laser light while rotating the cylindrical electrophotographic photosensitive member by the driving means contacting the outer peripheral portion of the flange, Provided is a method for measuring the shape of a cylindrical electrophotographic photosensitive member, which comprises measuring the outer diameter, runout, straightness, and roundness of the cylindrical electrophotographic photosensitive member.

In the method of the present invention, as a device for supporting the photosensitive member by the flanges fitted to the open portions at both ends of the cylindrical electrophotographic photosensitive member, for example, a device coaxial with the rotation reference axis of the photosensitive member is used. A round bar is fixed on a flat base having plane accuracy by a component that can move parallel to the rotation reference axis and the flat base, and the round bars are configured to face each other. An apparatus for supporting the photoconductor by inserting the round bar into the rotation center axis of the flange fitted to the open end portions of the photoconductor drum by moving is used.

The material of the round bar is preferably a metal or the like that is hard to be deformed, and its shape is, for example, a cylindrical round bar or a cylindrical structure, the tip of which has a pointed shape or a hemispherical shape. The processed product is preferable because it can be easily inserted into the rotation center axis of the flange. Further, the diameter of the round bar is equal to the inner diameter of the rotation center shaft of the flange.

As a method of giving rotation to a cylindrical electrophotographic photosensitive member, for example, the outer peripheral surface of a cylindrical or disk-shaped rotating member is brought into contact with the outer peripheral surfaces of flanges fitted to the open portions at both ends of the photosensitive drum. Therefore, an apparatus having a structure capable of transmitting smooth rotational drive to the photoconductor was used.
In this case, it is preferable that the outer peripheral surface of the cylindrical or disc-shaped rotating body does not idle between the outer peripheral surface of the flange and the outer peripheral surface of the flange. As a device for applying rotation to the cylindrical electrophotographic photosensitive member, for example, a ring-shaped member made of a highly elastic material such as rubber can be rotated, and a part of the device is pressed against the flange of the photosensitive member. It can be a hit device. Further, in the case where the flange fitted to the open portion of the cylindrical electrophotographic photosensitive member has a structure having a gear on its outer peripheral surface, the purpose is to mesh with this gear and transmit the rotational drive to the photosensitive member. It may be a device that rotates through the gears. Furthermore,
As a device for imparting rotation to the open portion of the cylindrical electrophotographic photosensitive member, for example, by connecting a rotary shaft of a rotary driving member such as an electric motor and a round bar supporting the photosensitive drum,
It is also possible to use a device that rotates the round bar itself to give rotational drive to the photosensitive drum.

The adhesive used for fixing the flange to the open portion of the cylindrical photosensitive drum is, for example, a heat-melting adhesive such as polyvinyl acetate, styrene-vinyl acetate copolymer, polyamide polybutyral; urea-based adhesive. , 2-component adhesives such as phenol-based, cresol-based, epoxy-based, unsaturated polyester-based, and alkyd-based adhesives; 1-component adhesives such as cyanoacrylate and anaerobic adhesives. An adhesive that does not adversely affect the film is preferable.

The photosensitive drum flange preferably has a structure for applying a driving force to the cylindrical photosensitive drum. Therefore, as the flange, a gear with a gear that meshes with the drive gear and a shape with which a protrusion mounted on a metal shaft that is a drive source meshes are used. It is possible to reduce the number of steps required when the process cartridge is detachably attached to the main body of the forming apparatus.

The flange is intended to hold the cylindrical photosensitive drum and to provide a rotational driving force, and can be made of metal or resin. In the case of metal, in terms of weight reduction, it is limited to light materials such as aluminum, and in general, die casting is performed to facilitate mass production, but since the shape accuracy is not sufficient, it is cut in the subsequent process. There are drawbacks in that it requires time and labor such as providing steps, and the cost is high. Therefore, the flange is preferably made of resin, and examples of the material thereof include phenol resin, amino resin, polyester resin, allyl resin, epoxy resin, ABS resin, acrylic resin, vinyl chloride resin, polystyrene, polyamide, and polyimide. , Polycarbonate, polyacetal, polyphenylene oxide,
Examples thereof include polyethylene terephthalate, polyarylate, polybutylene terephthalate, polysulfone, and polyether sulfone.

As a method of molding the resin flange, injection molding is preferable from the viewpoint of ease of mass production, but the same effect can be obtained with a cut molded product.

The material of the ground component attached to the flange is preferably highly conductive such as metal. For example, phosphor bronze, stainless steel or the like having spring properties is not deformed by an external force and is placed inside the photosensitive drum. It is preferable because it can be contacted at all times.

In the cylindrical electrophotographic photosensitive member to be measured in the present invention, the cylindrical photosensitive drum having a photosensitive layer has a photosensitive layer provided on a cylindrical conductive support.

Examples of the material for the conductive support include aluminum, copper, zinc, stainless steel, chromium, titanium,
Nickel, molybdenum, vanadium, indium, gold,
Examples include metals or alloys such as platinum, conductive polymers, conductive compounds such as indium oxide; paper, plastic films, ceramics, etc. coated, vapor-deposited or laminated with metals or alloys such as aluminum, palladium and gold. Metallic ones, especially aluminum ones, are preferable. If necessary, the surface of the conductive support may be subjected to chemical or physical treatment.

The photosensitive layer is of a first type in which a charge generating layer mainly composed of a charge generating material and a charge transporting layer mainly composed of a charge transporting material are sequentially laminated, a charge transporting layer and a charge generating layer are successively formed. It may be a laminated second type or a third type in which a charge generating material is dispersed in a charge transfer medium.

The first type photosensitive layer is formed by vapor deposition of a charge generating material or dispersion of fine particles of the charge generating material in a solvent in which a binder resin is dissolved, if necessary, and then coating and drying. Then, the charge transporting material may be used alone or, if necessary, a binder resin may be used in combination, and a solution in which the binder resin is dissolved is applied and dried.

In the second type of photosensitive layer, a solution in which a charge-transporting material is used alone or, if necessary, a binder resin is used in combination is coated on a conductive support and dried to generate a charge thereon. It can be obtained by vapor deposition of a material, or by applying a dispersion obtained by dispersing fine particles of a charge generating material in a solvent or a binder resin solution and drying.

The third type of photosensitive layer is prepared by dispersing fine particles of a charge generating material in a solution in which a charge transporting material is used alone or, if necessary, a binder resin is also used in combination, and this is used as a conductive support. It can be produced by coating on the surface and drying.

In the case of the first and second types of photosensitive layers, the thickness of the charge generating layer is preferably not more than 5 μm, particularly preferably 0.01 to 2 μm, and the charge transporting layer is particularly preferable. The thickness of the layer is preferably in the range of 3 to 50 μm, 5 to 3
The range of 0 μm is particularly preferable. In the case of the third electrophotographic photosensitive member, the thickness of the photosensitive layer is preferably in the range of 3 to 50 μm, particularly preferably 5 to 30 μm.

The proportion of the charge transport material in the charge transport layer in the first and second type photosensitive layers is 5 to 100% by weight.
Is preferable, and a range of 40 to 80% by weight is particularly preferable. The proportion of the charge generating material in the charge generating layers of the first and second type photosensitive layers is preferably in the range of 5 to 100% by weight, particularly preferably in the range of 40 to 80% by weight. The proportion of the charge transport material in the third type photosensitive layer is preferably in the range of 5 to 99% by weight, and the proportion of the charge generation material is 1
Is preferably in the range of 50 to 50% by weight, particularly preferably in the range of 3 to 20% by weight. In addition, in any of the first to third photosensitive layers, a plasticizer and a sensitizer can be used together with the binder resin.

Examples of the charge generation material include azo pigments such as monoazo pigments, disazo pigments and trisazo pigments;
Phthalocyanine pigments such as various metal phthalocyanines, metal-free phthalocyanines, and naphthalocyanines; condensed polycyclic pigments such as perinone pigments, perylene pigments, anthraquinone pigments, quinacridone pigments; squarylium dyes; azurenium dyes; thiapyrylium dyes; cyanine dyes And the like.

Particularly, phthalocyanines are suitable because they have high sensitivity in an electrophotographic system using a long wavelength light source such as a semiconductor laser or a light emitting diode.

The charge-generating material is not limited to those described here, and may be used alone or in combination of two or more when used.

The charge transport material is roughly classified into low molecular weight compounds and high molecular weight compounds.

Examples of the charge transport material of the low molecular weight compound include pyrene; carbazoles such as N-ethylcarbazole, N-isopropylcarbazole and N-phenylcarbazole; N-methyl-N-phenylhydrazino-3.
-Methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, p- (N, N-dimethylamino) benzaldehyde diphenylhydrazone, p- (N, N-diethylamino) benzaldehyde diphenyl Hydrazone, 1-
[4- (N, N-diphenylamino) benzylideneimino] -2,3-dimethyindoline, N-ethylcarbazole-3-methylidene-N-aminoindoline, N-ethylcarbazole-3-methylidene-N-aminotetrahydrokyrin Hydrazones such as; oxadiazoles such as 2,5-bis (p-diethylaminophenyl) -1,3,4-oxadiazole; 1-phenyl-3- (p-
Diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline, 1- [quinolyl- (2)]-3
Pyrazolines such as-(p-diethylaminophenyl) pyrazoline; tri-p-tolylamine, N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,
Arylamines such as 1'-biphenyl-4,4'-diamine; 1,1-bis (p-diethylaminophenyl)
Butadiene such as -4,4-diphenyl-1,3-butadiene; 4- (2,2-diphenylethenyl) -N, N
Examples include stills such as -diphenylbenzenamine and 4- (1,2,2-triphenylethenyl) -N, N-diphenylbenzenamine.

Examples of the charge transport material of the polymer compound include poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyvinylpyrene,
Examples thereof include polyvinyl anthracene, polyvinyl acridine, poly-9-vinylphenyl anthracene, pyrene-formamide resin, ethylcarbazole-formaldehyde resin, triphenylmethane polymer, and polyphenylalkylsilane.

The charge transporting material is not limited to those described here, and may be used alone or in combination of two or more when used.

As the binder resin which can be used if necessary, it is preferable to use a hydrophobic and electrically insulating polymer compound capable of forming a film. Examples of such high molecular weight polymers include polycarbonate, polyester, methacrylic resin, acrylic resin, polyvinyl chloride,
Polyvinylidene chloride, polystyrene, polyvinyl acetate, polyvinyl butyral, styrene-butadiene copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, Examples thereof include poly-N-vinylcarbazole, polyvinyl formal, and polysulfone.

The binder resin is not limited to the ones described here, and may be used alone or in combination with the binder resin.
It can be used as a mixture of more than one kind.

Further, in order to improve the film-forming property, flexibility and mechanical strength, additives such as known plasticizers and surface modifiers may be used together with these binder resins.

Examples of the plasticizer include biphenyl, biphenyl chloride, o-terphenyl, p-terphenyl,
Dibutyl phthalate, diethyl glycol phthalate,
Examples thereof include dioctyl phthalate, triphenyl phosphoric acid, methylnaphthalene, benzophenine, chlorinated paraffin, polypropylene, polystyrene and various fluorohydrocarbons.

Examples of the surface modifier include silicone oil and fluororesin.

Any known sensitizer can be used as the sensitizer which is optionally used in the photosensitive layer.

Examples of the sensitizer include chloranil, tetracyanoethylene, methyl violet, rhodamine B, cyanine dye, merocyanine dye, pyrylium dye and thiapyrylium dye.

Further, in order to improve storability, durability and environmental resistance, a deterioration preventing agent such as an antioxidant or a light stabilizer may be contained in the photosensitive layer. Examples thereof include phenol compounds, hydroquinone compounds, amine compounds and the like.

Furthermore, in order to improve the adhesive between the conductive support and the photosensitive layer and to prevent the injection of free charges from the conductive support to the photosensitive layer, a gap between the conductive support and the photosensitive layer is provided. ,
An adhesive layer or a barrier layer can be provided if necessary.

The materials used for these layers include, in addition to the polymer compound used for the binder resin, casein, gelatin, ethyl cellulose, nitrocellulose,
Carboxy-methyl cellulose, vinylidene chloride-based polymer latex, styrene-butadiene-based polymer latex, polyvinyl alcohol, polyamide, polyurethane, phenol resin, aluminum oxide, tin oxide,
Titanium oxide and the like can be used, but the film thickness is preferably 1 μm or less.

When a laminated photosensitive layer having a charge generation layer and a charge transport layer is formed by coating, the solvent that dissolves the binder resin varies depending on the type of binder resin, but does not dissolve the lower layer. It is desirable to select from among them.
Specific examples of the organic solvent include, for example, methanol,
Alcohols such as ethanol and n-propanol; ketones such as acetone, methyl ethyl ketone and cyclohexanone; amides such as N, N-dimethylformaldehyde and N, N-dimethylacetamide; ethers such as tetrahydrofuran, dioxane and methylcellosolve; acetic acid Esters such as methyl and ethyl acetate; Sulfoxides and sulfones such as dimethyl sulfoxide and sulfolane;
Aliphatic hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride and trichloroethane; aromatics such as benzene, toluene, xylene, monochlorobenzene and dichlorobenzene.

As the coating method, for example, a coating method such as a dip coating method can be used.

[0044]

According to the method for measuring the shape of a cylindrical electrophotographic photosensitive member of the present invention, the external shape can be measured while the photosensitive member is rotated a certain amount without contacting the photosensitive layer on the outer peripheral surface of the photosensitive member. Can be done.

[0045]

Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments.

(Production Example) As a charge generating material, a material obtained by synthesizing titanyl phthalocyanine and recrystallizing it from a concentrated sulfuric acid solution was used. This titanyl phthalocyanine crystal was crushed with an attritor mill at 90 ° C for 90 minutes 5
5 parts of polyvinyl butyral (S-REC BH-3, manufactured by Sekisui Chemical Co., Ltd.) and 90 parts of methylene chloride,
It was dispersed using a ball mill to obtain a coating material for forming the charge generation layer. This coating material was applied by dip coating to the outer peripheral surface of an aluminum drum having an outer diameter of 30 mm and a length of 260 mm, the surface of which was finished to a surface roughness R _Z = 0.1 μm by a precision cutting method, and the film thickness after drying was 0. It was applied so as to have a thickness of 4 μm and dried to form a charge generation layer.

Next, the formula of the hole transport material

[0048]

Embedded image

9 parts of a hydrazone compound represented by and a polycarbonate resin (Z-200, manufactured by Mitsubishi Gas Chemical Co., Inc.)
10 parts by volume) was dissolved in a mixed solvent consisting of 65 parts of methylene chloride and 15 parts of monochlorobenzene to prepare a coating material for the charge transport layer. This coating material was applied onto the charge generation layer by a dip coating method so that the film thickness after drying was 23 μm, and dried to form a charge transport layer, thereby obtaining a photosensitive drum.

(Embodiment 1) FIG. 1 is a device layout view for specifically explaining the present invention, FIG. 2 is a perspective view of a flange used in this embodiment, and FIGS. FIG. 5 is a perspective view and a cross-sectional view of a cylindrical photoconductor in which flanges are fitted to open portions at both ends of a hollow cylindrical photoconductor drum, and FIG. 5 is a perspective view of a rotary driving device for a cylindrical electrophotographic photoconductor. 6 is an apparatus layout diagram for specifically explaining the apparatus of the present invention, and FIG. 11 is a block diagram showing the configuration of the entire apparatus.

As shown in FIG. 2, the flange used in the cylindrical photosensitive member used in Example 1 is attached with a grounding part by welding a part of the flange using heat or ultrasonic waves. ing. The center axis of rotation of this flange has a uniform inner diameter and a straightness of 0.01 m.
It is manufactured with high accuracy of about m. The grounding part has a structure capable of coming into contact with a metal pin inserted from the image forming apparatus through a rotation center shaft opened in advance in the flange. The photosensitive drum in the cylindrical electrophotographic photosensitive member has a deviation of about 0.02 mm in shape accuracy of the outer circumference or the inner surface of the entire length of the cylindrical drum made of aluminum without a photosensitive layer on the outer peripheral surface thereof. If the outer peripheral surface has a photosensitive layer, the outer peripheral surface has a shape accuracy of 0.0%.
It is about 2 mm.

Next, as shown in FIG. 11, the device used in the measuring method of the present invention comprises a photoconductor rotating device, a non-contact type shape measuring device using laser light, and an output device for printing and displaying the measurement result. Has been done. The non-contact type shape measuring device is composed of a laser oscillator of a laser projecting unit and a controller that calculates a size from a time when a shadow of a laser beam is blocked by a photoconductor by a condenser lens of a laser receiving unit.

As shown in FIG. 1, the photoconductor rotating device used in the measuring method of this embodiment is roughly composed of three devices.

The first device has such a high cylindricity and straightness that it is long enough to touch the grounding component attached to the flange, and at the same time, the difference between its diameter and the inner diameter of the rotation center axis of the flange is -0.15. Two round rods for supporting a cylindrical electrophotographic photosensitive member set at ˜ + 0.15 mm are fixed so as to be coaxial with each other and face each other, and to the rotation center axis of a flange fitted to both ends of the drum. It is a device that can be supported by inserting it. This device has a structure in which one of the devices can be slid and the photoconductor can be easily attached and detached.

The second device is a device for giving rotational drive to the photoconductor. For this device, for example, a device is provided in which a disk is attached to the rotary shaft of a rotary drive device such as an electric motor, and the rotary drive is transmitted to the drum by contacting the outer periphery of the flange. In addition, the entire device can be moved by moving the lever,
The drum can be easily attached and detached with the disc separated from the photoconductor. Further, as shown in FIG. 5, a pulley is attached to the rotating shaft instead of the disk to form a structure capable of rotating a V belt, a flat belt, a rubber band, etc., and the belt is pressed against the flange of the photoconductor to drive the rotation. It may be a device for giving. Further, two devices for giving rotational drive to the photoconductor may be provided to the flanges at both ends of the photoconductor.

The third apparatus is an external shape measuring apparatus for the photoconductor, and a non-contact type measuring apparatus which is generally commercially available is used. Then, the laser light projecting portion and the light receiving portion are arranged so that the photosensitive drum is irradiated with the laser light from the vertical direction. Further, if the laser projecting portion and the light receiving portion can move in parallel with the longitudinal direction of the photoconductor, it is possible to measure any position of the photoconductor. In addition, a knife-edge-shaped reference member is installed in the apparatus so as to be parallel to the central axis in the longitudinal direction of the photoconductor and kept at a constant distance from the photoconductor.

FIG. 6 shows how the shape measurement is performed by the apparatus of the present invention composed of three apparatuses. After inserting the supporting round bar from both sides into the rotation center axis of the flange of the photoconductor, this is fixed. The photoconductor can be rotated by bringing the outer peripheral surface of the disk attached to the rotating shaft of the electric motor, which is the driving device, into contact with the outer peripheral surface of the flange fitted to the end of the photoconductor. At the same time as the rotation, the shape measuring device is operated to irradiate the photoconductor with laser light. With the above operation, the outer shape of the photoconductor can be measured.

Next, in order to confirm the effect of this embodiment,
After fitting the flange shown in FIG. 2 to the end of the photosensitive drum obtained in the manufacturing example, the outer diameter of the same photosensitive member is measured by the shape measuring device while rotating the outer peripheral surface of the flange by the hand of the measurer. And the result of measuring the shake 20 times and the result of measuring the outer diameter and the shake of the same photoconductor 20 times by the shape measuring device while rotating using the device according to the method of the present invention described above. 1
It was shown to.

[0059]

[Table 1]

From Table 1, it can be seen from the measurement results of the outer diameter and the shake that, when the photosensitive drum is rotated by hand, the standard deviation is large and the dispersion of the measurement results is large as compared with the measuring method of the present invention. Understandable. Further, in the shake measurement result, it is clear that the average value is large when the photoconductor is rotated by hand. However, the outer diameter is less affected by such a difference in driving method on the principle that the width of the shadow of the object to be measured by the laser light is measured. From these results, when rotational drive is applied, since the force applied by the hand is not constant, the fluctuation of the rotation of the photosensitive drum is large and the measurement results vary widely, but in the measurement method of the present invention, constant rotational drive is performed. It can be understood that the fluctuation of the rotation is small and the measurement results tend to have little variation due to the application.

(Embodiment 2) FIG. 7 is a perspective view of a flange fitted to the end of the cylindrical photosensitive member used in this embodiment.
FIG. 8 is a perspective view of a cylindrical photosensitive member used in this embodiment, and FIG. 9 is an apparatus diagram used in the method of this embodiment. As shown in FIG. 7, the outer peripheral surface of the flange has a spur tooth shape, and a gear having a high meshing precision with the spur tooth of the flange is attached to the rotary shaft of the rotary drive device as shown in FIG. Except that the photosensitive member is rotationally driven by
As a result of measuring the outer diameter and the shake of the photosensitive member 20 times in the same manner as in Example 1, the standard deviation is smaller than that in the case where the photosensitive drum is manually rotated by the measuring method of the present invention. The variation was small.

(Embodiment 3) FIG. 10 is an apparatus diagram specifically explaining Embodiment 3. The round bar of the photoconductor supporting device in this device rotates itself by being coupled to the rotary shaft of a rotary driving body such as an electric motor. As a result, except that the rotational drive is given to the photoconductor,
As a result of measuring the outer diameter and the shake of the photosensitive member 20 times in the same manner as in Example 1, the standard deviation is smaller than that in the case where the photosensitive drum is manually rotated by the measuring method of the present invention. The variation was small.

[0063]

According to the measuring method of the present invention, when the shape of the cylindrical electrophotographic photosensitive member is measured, a constant rotation can be obtained with high accuracy, and the both ends of the rotating shaft are fitted. Regardless of the shape of the ground component attached to the flange, the measurement can be performed after supporting the photoconductor.

[Brief description of drawings]

FIG. 1 is a layout of a measuring device used in Example 1.

2 is a perspective view of a flange used in Example 1. FIG.

FIG. 3 is a perspective view of a cylindrical electrophotographic photosensitive member used for measurement in Example 1.

FIG. 4 is a cross-sectional view of a cylindrical electrophotographic photosensitive member provided for measurement in Example 1.

FIG. 5 is a perspective view of an example of an apparatus for applying rotational drive used in the measuring method of the present invention.

FIG. 6 is a perspective view showing a state in which a photosensitive drum is installed in the measuring device used in Example 1.

7 is a perspective view of a flange used in Example 2. FIG.

FIG. 8 is a perspective view of a cylindrical electrophotographic photosensitive member used for measurement in Example 2.

FIG. 9 is a perspective view showing a state in which a photosensitive drum is installed in the measuring device used in Example 2.

FIG. 10 is a perspective view showing a state in which a photosensitive drum is installed in the measuring device used in Example 3.

FIG. 11 is a block diagram showing the overall device configuration of the first embodiment.

[Explanation of symbols]

 1 Measuring Device 2 Electric Motor 3 Knife Edge 4 Laser Light Projector (Laser Transmitter) 5 Laser Light Receiver D Cylindrical Electrophotographic Photoreceptor 6 Grounding Part 7A Flange 7B Flange (with Gear) 8 Photosensitive Drum 9 Round Bar 10 Disk (roller) 11 Lever 12 Gear 13 Electric motor (rotatable round bar) 14 Pulley 15 Belt

Claims (1)

[Claims] 1. A flange having a concave rotation center shaft portion fitted in open portions at both ends of a cylindrical electrophotographic photosensitive member is fixed by two fixing pins having a convex portion corresponding to the concave rotation center shaft portion of the flange. By irradiating with laser light while gripping and rotating the cylindrical electrophotographic photosensitive member by the driving means that comes into contact with the outer peripheral portion of the flange, the outer diameter, runout, straightness and A method for measuring the shape of a cylindrical electrophotographic photosensitive member, which comprises measuring the roundness.