JP2008151324A - Hollow roller for office automation roller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hollow rotor which can prevent the separation or loosening of a resin shaft end flange from a metal sleeve. <P>SOLUTION: The hollow rotor 10 for OA rollers presses directly an annular fitting member 4 in which the difference of a coefficient of thermal expansion to the metal sleeve 1 is smaller than the shaft end flanges 2A, 2B inside the metal sleeve 1 or indirectly through the resin member. By fixing the shaft end flanges 2A, 2B to the fitting member 4, the shaft end flanges 2A, 2B are fixed to the metal sleeve 1 which constitutes the hollow roller. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hollow rotating body having a resin shaft end flange disposed on both ends of a metal sleeve, such as a shaft body of an OA roller, and in particular, the shaft end flange is loosened or detached from the metal sleeve. It relates to things that can be prevented.

  In an image forming apparatus using an electrophotographic system such as a copying machine or a printer, various conductive rollers such as a developing roller and a charging roller are used in each step of image formation. These rollers are electrically conductive. A conductive coating layer is formed on the outside of the shaft body, and in order to reduce the weight of the roller, as shown in a sectional view in FIG. There has been proposed one constituted by a hollow rotating body 90 comprising a metal sleeve 91 arranged and respective resin-made shaft end flanges 92 for fixing the metal sleeve 91 to the metal core 93 at both axial ends. . Also, in the magnetic developing roller, a hollow rotating body having the same structure is disposed outside the magnet roller, and the magnetic toner is transferred outside the hollow rotating body.

  In such a hollow rotating body 90, the resin shaft end flange 92 is fixed to the metal sleeve 91 by adhesive press fitting, caulking, notching or the like. However, caulking, notches and the like can be securely fastened, but the cost is high. On the other hand, the method of fitting the resin shaft end flange 92 inside the metal sleeve 91 by press-fitting is advantageous in terms of cost, but due to the difference in thermal expansion coefficient between the metal sleeve and the resin member, the external temperature If you do, loosening may occur.

JP 2004-278590 A

  This invention is made | formed in view of such a problem, and it aims at providing the hollow rotary body which can prevent that a resin-made shaft end flange remove | deviates from a metal sleeve, or loosens.

<1> is an OA comprising a metal sleeve disposed on a central axis, and respective resin shaft end flanges fixed to both ends of the metal sleeve in the axial direction and supporting the metal sleeve on the central axis. In the hollow rotating body for rollers,
An annular locking member having a smaller difference in thermal expansion coefficient from the metal sleeve than the shaft end flange is press-fitted directly into the metal sleeve or indirectly through the resin member, It is a hollow rotating body for an OA roller formed by fixing the shaft end flange to the metal sleeve by fixing the shaft end flange to the locking member.

  <2> is a hollow rotator for an OA roller in which the locking member is made of metal in <1>.

  <3> In <1> or <2>, at least a part of a portion of the shaft end flange located inside the metal sleeve is formed in a cylindrical shape having an inner diameter larger than the outer diameter of the core metal. The OA roller hollow rotator is formed by press-fitting the locking member inside the cylindrical portion of the shaft end flange.

  According to <1>, the annular locking member whose thermal expansion coefficient difference from the metal sleeve is smaller than that of the shaft end flange is directly inside the metal sleeve or indirectly through the resin member. Since the press-fitting is performed, the locking member can be prevented from loosening with respect to the metal sleeve even if there is a slight temperature change, and the shaft end flange is fixed to the locking member. Even with a slight temperature change, the shaft end flange can be prevented from coming off or loosening from the metal sleeve.

  According to <2>, since the locking member is made of metal, the difference in coefficient of thermal expansion between the metal sleeve and the locking member can be further reduced, and the locking member and the metal sleeve can be fixed. Further, it can be made stronger without depending on the temperature.

  According to <3>, since the locking member is press-fitted inside the cylindrical portion of the shaft end flange, an elastic resin shaft end flange is sandwiched between the locking member and the metal sleeve. As a result, it is possible to facilitate the press-fitting of the locking member and to further secure the shaft end flange to the metal sleeve.

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a cross-sectional view showing a hollow rotating body for an OA roller according to the first embodiment of the present invention,
The hollow rotating body 10 fixes the core metal 3 disposed on the central axis C, the metal sleeve 1 disposed around the core metal 3, and the metal sleeve 1 to the core metal 3 at both axial end positions. Each of the shaft end flanges 2A, 2B is made of resin, and the metal core 3 is press-fitted inside the shaft end flanges 2A, 2B. The shaft end flanges 2A, 2B are also inside the metal sleeve 1. The metal sleeve 1 is fitted by press-fitting, and as a result, the metal sleeve 1 can be arranged on the central axis C.

  At least a part of the portion of the shaft end flanges 2A and 2B located inside the metal sleeve 1 is formed in a cylindrical shape having an inner diameter larger than the outer diameter of the core metal 3, and the shaft end flanges 2A and 2B. An annular locking member 4 is fitted inside the cylindrical portion by press-fitting.

  In addition, since the cored bar 3 penetrates through the center part of the locking member 4, it is necessary to make it annular, and its inner diameter needs to be larger than the outer diameter of the cored bar 3. Or a thick cylindrical shape. Further, the inner surface of the locking member 4 may not be a perfect circle.

  That is, the locking member 4 is indirectly press-fitted into the inside of the metal sleeve 1 via the shaft end flanges 2A and 2B, and the shaft end flanges 2A and 2B are inserted into the inner periphery of the metal sleeve 1 by the locking member 4. By being sandwiched between the surfaces, the fixing to the locking member 4 and the fixing to the metal sleeve 1 are strengthened.

  Here, as a material of the metal sleeve 1, aluminum, iron, or the like is used. In addition, the resin material used for the shaft end flanges 2A and 2B may be appropriately selected from general-purpose resins and engineering plastics, and is not particularly limited. It is preferable that it is moldable.

  As the material for the shaft end flange, specifically, in the case of engineering plastics, for example, polyacetal, polyamide resin (for example, polyamide 6, polyamide 6,6, polyamide 12, polyamide 4,6, polyamide 6,10, polyamide 6, 12, polyamide 11, polyamide MXD6 (polyamide obtained from metaxylenediamine and adipic acid), polyoxymethylene (POM), polybutylene terephthalate, polyphenylene oxide, polyphenylene ether, polyphenylene sulfide, polyethersulfone, polycarbonate, polyimide , Polyamideimide, Polyetherimide, Polysulfone, Polyetheretherketone, Polyethylene terephthalate, Polyarylate, Liquid crystal polymer, Polytetrafluoroethylene Or the like can be mentioned Oroechiren. Examples of the general-purpose resin include polypropylene, acrylonitrile-butadiene-styrene (ABS) resin, polystyrene, and polyethylene. In addition, a melamine resin, a phenol resin, a silicone resin, etc. can also be used. These may be used individually by 1 type and may be used in combination of 2 or more type.

  Among these, engineering plastics are preferable, and polyacetal, polyamide resin, polybutylene terephthalate, polyphenylene ether, polyphenylene sulfide, polycarbonate, and the like are particularly preferable because they are thermoplastic and have excellent moldability and mechanical strength. In particular, polyamide 6 · 6, polyamide MXD6, polyamide 6 · 12, polybutylene terephthalate, or a mixed resin thereof is preferable. Although there is no problem in using a thermosetting resin, it is preferable to use a thermoplastic resin in consideration of recyclability.

  As the conductive agent for making the shaft end flange 4 conductive, various materials can be used as long as they can be uniformly dispersed in the resin material. Powdered conductive agents such as powder, metal powder such as carbon fiber, aluminum, copper and nickel, metal oxide powder such as tin oxide, titanium oxide and zinc oxide, and conductive glass powder are preferably used. These may be used individually by 1 type and may be used in combination of 2 or more type. The blending amount of the conductive agent may be selected so that an appropriate resistance value can be obtained according to the intended use and situation of the conductive roller, and is not particularly limited. It is preferable to set it as 5 to 40 weight%, especially 5 to 20 weight%.

  In the material of the shaft end flange 4, various conductive or non-conductive fibrous materials, whiskers, ferrites, and the like can be blended as needed for the purpose of reinforcement or increase in weight. Examples of the fibrous material include fibers such as carbon fiber and glass fiber, and examples of the whisker include inorganic whiskers such as potassium titanate. These may be used individually by 1 type, and may be used in combination of 2 or more types. These blending amounts can be appropriately selected according to the length and diameter of the fibrous material or whisker to be used, the type of the main resin material, the intended roller strength, etc. 70% by weight, in particular 10-20% by weight.

  Moreover, as the metal core 3, for example, sulfur free-cutting steel, aluminum, stainless steel, or the like subjected to nickel, zinc plating, or the like can be used.

  Here, it is a feature of the present invention that the locking member 4 is made of a material whose difference in thermal expansion coefficient from the metal sleeve is smaller than that of the shaft end flanges 2A, 2B. Among them, a material made of metal is preferable. Furthermore, using the same metal material as the metal sleeve 1 reduces the difference in coefficient of thermal expansion and prevents the locking member 4 from coming off or loosening from the metal sleeve 1 even if there is a large temperature change. It is more preferable in that it can be performed.

  Here, the locking member 4 can be press-fitted inside the shaft end flanges 2A and 2B after the shaft end flanges 2A and 2B are press-fitted into the metal sleeve 1, but as shown in a sectional view in FIG. The shaft end flanges 2 </ b> A and 2 </ b> B can be fixed to the metal sleeve 1 by press-fitting shaft end flanges 2 </ b> A and 2 </ b> B with the locking member 4 attached to the inside in advance to the inside of the metal sleeve 1. Prior to press-fitting the shaft end flanges 2A and 2B into the metal sleeve 1, when the locking member 4 is attached to the shaft end flanges 2A and 2B, the locking member 4 is engaged by press-fitting the shaft end flanges 2A and 2B. The stopper member 4 may be attached, or after the locking member 4 is disposed in the mold cavity in advance, a resin material is injected into the cavity to insert the shaft end flanges 2A and 2B. Good.

  FIG. 4 is a cross-sectional view showing the hollow rotator according to the second embodiment of the present invention. The hollow rotator 20 is similar to the hollow rotator 10 and includes a core metal 3 disposed on the central axis C. The metal sleeve 1 disposed around the core metal 3 and the resin shaft end flanges 12A and 12B for fixing the metal sleeve 1 to the core metal 3 at both axial end positions thereof. The metal sleeve 1 is placed on the central axis C by being fitted inside the shaft end flanges 12A and 12B by press fitting, and the shaft end flanges 12A and 12B are fitted inside the metal sleeve 1 by press fitting. Is done.

  A concave portion 13 for fixing the locking member 14 is formed in an annular central portion of the outer peripheral surface of the shaft end flanges 12 </ b> A and 12 </ b> B that is press-fitted into the metal sleeve 1. 14 is press-fitted directly inside the metal sleeve 1.

  With this configuration, the shaft end flanges 12 </ b> A and 12 </ b> B are fixed to the locking member 4 that is securely press-fitted and fixed inside the metal sleeve 1, whereby the fixing to the metal sleeve 1 is strengthened.

  The materials for the metal sleeve 1, the shaft end flanges 12 </ b> A and 12 </ b> B, the core metal 3, and the locking member 14 are the same as those described in the first embodiment, and a description thereof is omitted.

  Here, press-fitting the locking member 4 into the inside of the metal sleeve 1 is performed by using shaft end flanges 12A and 12B in which the locking member 14 is previously mounted on the outer peripheral surface as shown in a sectional view in FIG. 1 may be press-fitted inside. In this case, after the locking member 4 is disposed in advance in the mold cavity, insert molding may be performed in which a resin material is injected into the cavity to mold the shaft end flanges 2A and 2B.

  FIG. 6 is a cross-sectional view showing the hollow rotator of the third embodiment. The hollow rotator 30 includes a metal sleeve 1 and a resin shaft end flange that is fitted and fixed at both ends in the axial direction of the metal sleeve 1. The metal sleeve 1 is disposed on the central axis C by providing the resin shaft end flanges 22A and 22B on the central axis C.

  An annular locking member 34 is press-fitted inside the resin shaft end flanges 22 </ b> A and 22 </ b> B inside the portion fitted inside the metal sleeve 1. That is, the locking member 24 is indirectly press-fitted inside the metal sleeve 1 via the shaft end flanges 2A and 2B, and the shaft end flanges 22A and 22B are inserted into the inner periphery of the metal sleeve 1 by the locking member 24. By being sandwiched between the two surfaces, the fixing to the locking member 24 and the fixing to the metal sleeve 1 are strengthened.

  Here, it is one of the features of the present invention that the engaging member 24 is made of a material whose thermal expansion coefficient difference from the metal sleeve 1 is smaller than that of the shaft end flanges 22A and 22B. Further, it is preferable to use the same metal material as that of the metal sleeve 1, so that the difference in the thermal expansion coefficient is reduced, and the locking member 4 is detached or loosened from the metal sleeve 1 even if there is a large temperature change. This is more preferable in that it can be prevented.

  In the hollow rotating body 30 of this embodiment, the core metal 3 in the hollow rotating body 10 of the first embodiment is eliminated, and instead, the function of the shaft end of the core metal 3 is added to the shaft end flanges 22A and 22B. Only the point is different from the first embodiment, and the other points are the same as the first embodiment.

  FIG. 7 is a cross-sectional view showing the hollow rotator of the fourth embodiment. The hollow rotator 40 includes a metal sleeve 1 and a resin shaft end flange that is fitted and fixed at both ends in the axial direction of the metal sleeve 1. The metal sleeve 1 is disposed on the central axis C by positioning the resin shaft end flanges 32A and 32B on the central axis C.

  A concave portion 33 for fixing the locking member 34 is formed in an annular central portion of the outer peripheral surface of the shaft end flanges 32 </ b> A and 32 </ b> B that is press-fitted into the metal sleeve 1. 34 is directly press-fitted inside the metal sleeve 1.

  With this configuration, the shaft end flanges 32 </ b> A and 32 </ b> B are fixed to the locking member 34 that is securely press-fitted and fixed inside the metal sleeve 1, whereby the fixing to the metal sleeve 1 is strengthened.

  Further, as described above, it is one of the features of the present invention that the locking member 24 is made of a material having a difference in thermal expansion coefficient from the metal sleeve 1 that is smaller than that of the shaft end flanges 22A and 22B. is there.

  The hollow rotator 40 of this embodiment eliminates the core metal 3 in the hollow rotator 20 of the second embodiment, and instead adds the function of the shaft end of the core metal 3 to the shaft end flanges 32A and 32B. Only the point is different from the second embodiment, and the other points are the same as the second embodiment.

  The hollow rotating body 30 having the structure as shown in FIG. 6 is formed as an example, and the hollow rotating body different from that of the example only in that the locking member 24 in FIG. Compared.

  Table 1 shows the specifications of the members used in this experiment. Table 2 shows the measurement results of the pull-out strength. For the measurement of the pull-out strength, the hollow rotating body is left for 3 hours in an environment at 60 ° C and then left for 3 hours in an environment at -10 ° C. The shaft end flange was pulled out of the metal sleeve both before and after the environmental test, and the force when the shaft end flange was detached from the metal sleeve was measured.

  As can be seen from Table 2, it can be seen that the hollow rotating body of the example has a very small drop in strength after the environmental test as compared with the conventional example.

It is sectional drawing which shows the conventional hollow rotary body. It is sectional drawing which shows the hollow rotary body of 1st embodiment which concerns on this invention. It is sectional drawing of the shaft end flange which attached the securing member. It is sectional drawing which shows the hollow rotary body of 2nd embodiment which concerns on this invention. It is sectional drawing of the shaft end flange which attached the securing member. It is sectional drawing which shows the hollow rotary body of 3rd embodiment which concerns on this invention. It is sectional drawing which shows the hollow rotary body of 4th embodiment which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal sleeve 2A, 2B Shaft end flange 3 Core metal 4 Locking member 10 Hollow rotary body 12A, 12B Shaft end flange 13 Outer peripheral surface recessed part of shaft end flange 14 Locking member 20 Hollow rotary body 22A, 22B Shaft end flange 23 Shaft Outer peripheral surface recess of end flange 24 Locking member 30 Hollow rotating body 32A, 32B Shaft end flange 33 Outer peripheral surface recess of shaft end flange 34 Locking member 40 Hollow rotating body

Claims (3)

A hollow rotating body for an OA roller comprising a metal sleeve disposed on a central axis and respective resin shaft end flanges fixed to both ends in the axial direction of the metal sleeve and supporting the metal sleeve on the central axis In
An annular locking member having a smaller difference in thermal expansion coefficient from the metal sleeve than the shaft end flange is press-fitted directly into the metal sleeve or indirectly through the resin member, A hollow rotating body for an OA roller, wherein the shaft end flange is fixed to the metal sleeve by fixing the shaft end flange to the locking member.   The hollow rotating body for an OA roller according to claim 1, wherein the locking member is made of metal.   At least a part of a portion of the shaft end flange positioned inside the metal sleeve is formed in a cylindrical shape having an inner diameter larger than the outer diameter of the cored bar, and the locking member is a cylinder of the shaft end flange. The hollow rotator for an OA roller according to claim 1 or 2, wherein the hollow rotator is press-fitted inside the shaped portion.

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