JP2011080110A - Holder for surface treatment of spherical body, method for surface-treating spherical body and method for manufacturing spherical component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a holder for a surface treatment of a spherical body, which enables the whole area of the surface of the spherical body to be surface-treated while precisely grasping the temperature of the spherical body; a method for surface-treating the spherical body; and a method for manufacturing a spherical component. <P>SOLUTION: The holder 1 which is the holder for the surface treatment of the spherical body includes a first holding plate 10 having a plurality of through-holes 11 therein and a second holding plate 20 having a plurality of through-holes 21 therein. The through-holes 21 of the second holding plate 20 are formed so as to be in a position corresponding to the through-holes 11 of the first holding plate 10 when the second holding plate 20 is arranged along the first holding plate 10. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spherical surface treatment jig, a spherical surface treatment method, and a spherical component manufacturing method, and more specifically, a spherical shape that enables surface treatment to be performed on the entire surface. The present invention relates to a body surface treatment jig, a spherical body surface treatment method, and a spherical part manufacturing method.

  When surface treatment such as surface modification treatment or coating treatment is performed on the spherical body, unless the surface treatment is performed in a state where the spherical body is floated, the spherical body and a jig for holding the spherical body, etc. Surface treatment will be performed in the state which contacted the support member. As a result, the surface treatment may not sufficiently proceed in a region (contact region) in contact with the support member on the surface of the spherical body. In particular, when the contact area is large, or when progress of surface treatment in the contact area due to diffusion from areas other than the contact area (non-contact area) cannot be expected, surface treatment is performed on the entire surface. The problem of being unable to do so arises.

  On the other hand, the surface treatment can be performed on the entire surface of the spherical body by performing the surface treatment with the spherical body floating. However, when the surface treatment is carried out in a state where the spherical body is floated, there are problems that the processing cost increases and the number, size, weight, etc. of the spherical body are limited.

  On the other hand, the surface treatment method of the spherical body which implements surface treatment, rolling or rotating a spherical body is proposed (for example, refer patent documents 1-3). Thereby, surface treatment can be implemented with respect to the whole surface.

JP-A-9-209117 JP 2003-73807 A JP 2003-59695 A

  In the surface treatment of a spherical body, the temperature of the spherical body often affects the speed and quality of the surface treatment. In this case, it is preferable that the surface treatment is performed while measuring the temperature of the spherical body. However, the method of performing the surface treatment while rolling or rotating the spherical body as described above has a problem that it is difficult to accurately grasp the temperature of the spherical body during the progress of the surface treatment.

  Accordingly, an object of the present invention is to provide a spherical surface treatment jig and a spherical body surface capable of performing surface treatment on the entire surface while accurately grasping the temperature of the spherical body. It is to provide a processing method and a method for manufacturing a spherical part.

  Further, in the surface treatment of the spherical body, it is preferable that as many spherical bodies as possible are surface-treated at the same time from the viewpoint of reducing the processing cost. However, in the conventional spherical body surface treatment methods including the spherical body surface treatment methods disclosed in Patent Documents 1 to 3, when a plurality of spherical bodies are surface-treated at the same time, the spacing between the spherical bodies is appropriate. There is a problem that normal surface treatment may not be performed due to contact between the spherical bodies.

  Accordingly, another object of the present invention is to provide a spherical surface treatment jig and a spherical surface treatment method that enable normal surface treatment to be performed on the entire surface of a plurality of spherical bodies. And a method of manufacturing a spherical part.

  The surface treatment jig according to one aspect of the present invention includes a first holding member having a plurality of through holes and a second holding member having a plurality of through holes. The plurality of through holes of the second holding member are formed so as to be positioned corresponding to the plurality of through holes of the first holding member by arranging the second holding member along the first holding member. Yes.

  By using the surface treatment jig in one aspect of the present invention, the surface treatment can be performed as follows. First, surface treatment is performed by supporting one spherical body in each of the plurality of through holes of the first holding member. Next, in a state where the second holding member is disposed along the first holding member so that the plurality of through holes of the second holding member are positioned corresponding to the plurality of through holes of the first holding member, The spherical body is sandwiched between the first holding member and the second holding member. Then, after reversing the positional relationship between the first holding member and the second holding member, the first holding member is separated from the spherical body, whereby the spherical body is 1 in each of the plurality of through holes of the second holding member. Surface treatment is carried out with support one by one.

  By carrying out the surface treatment in such a procedure, the surface treatment is carried out over the entire surface of each rolling element because the region in contact with the first holding member and the region in contact with the second holding member are different. Is done. In addition, since the spherical body is surface-treated while being supported in the through holes of the first holding member or the second holding member, the surface treatment can be performed while accurately grasping the temperature of the spherical body. As a result, according to the surface treatment jig in one aspect of the present invention, it is possible to perform the surface treatment on the entire surface of the spherical body while accurately grasping the temperature of the spherical body. A jig can be provided.

  In the surface treatment jig according to the first aspect, preferably, a relative positional relationship between the first holding member and the second holding member in a state where a spherical body is sandwiched between the first holding member and the second holding member. Further, a fixing member for fixing is provided.

  Thereby, when the positional relationship between the first holding member and the second holding member is reversed with the spherical body held between the first holding member and the second holding member, the spherical body can be supported more reliably. It becomes.

  In the surface treatment jig according to the one aspect, preferably, the plurality of through holes are arranged at intervals of at least twice the diameter of the spherical body. This makes it possible to maintain a sufficient interval between the spherical bodies. As a result, even when a surface treatment that applies voltage between the spherical body and other members, such as plasma nitriding, is performed, the generation of hollow cathodes (hollow cathodes) between the spherical bodies is more reliably suppressed. can do.

  In the surface treatment jig according to the above aspect, the through holes are preferably arranged at equal intervals. As a result, a large number of through holes can be densely arranged in the surface treatment jig, which can contribute to an improvement in the surface treatment efficiency.

  The spherical body surface treatment method according to one aspect of the present invention is a spherical body surface treatment method that is performed using the spherical surface treatment jig according to one aspect of the present invention. The spherical body surface treatment method includes a step of holding a plurality of spherical bodies by the first holding member by supporting the spherical bodies one by one in each of the plurality of through holes of the first holding member, and a first holding And a step of performing a surface treatment on the plurality of spherical bodies held by the member. The spherical surface treatment method further includes the positions of the first holding member and the second holding member in a state where the plurality of spherical bodies subjected to the surface treatment are sandwiched between the first holding member and the second holding member. A step of reversing the relationship, and detaching the first holding member from the plurality of spherical bodies to support one spherical body in each of the plurality of through holes of the second holding member, thereby allowing the second holding member to A step of holding the plurality of spherical bodies, and a step of performing a surface treatment on the plurality of spherical bodies held by the second holding member.

  In the spherical body surface treatment method according to the above aspect, the spherical body is surface-treated in a state of being held in the through hole of the first holding member and is held in the through hole of the second holding member. Surface treatment is performed even in the state. Here, the spherical body moves with respect to the surface treatment jig in either the state of being held by the first holding member and being heat-treated or the state of being held by the second holding member and being heat-treated. There is no need to let them. Therefore, the surface treatment can be performed while accurately measuring and grasping the temperature of the spherical body. In addition, since the contact area of the spherical body with the surface treatment jig can be changed between the state of being held by the first holding member and the state of being held by the second holding member, the surface of the spherical body Surface treatment can be performed on the entire area. As described above, according to the spherical body surface treatment method according to the above aspect, the spherical body can be subjected to surface treatment over the entire surface while accurately grasping the temperature of the spherical body. A surface treatment method can be provided.

  In the spherical body surface treatment method according to one aspect of the present invention, the spherical body is made of a conductor, and the surface treatment is performed by applying a voltage between the spherical body and a member disposed opposite to the spherical body. May be carried out while being applied.

  Surface treatment performed while a voltage is applied between a spherical body and a member arranged opposite to the spherical body, for example, plasma nitriding, plasma carburizing, PVD (Physical Vapor Deposition), CVD (Chemical) In Vapor Deposition (chemical vapor deposition), etc., it is desirable to carry out the treatment while grasping the temperature of the spherical body. Therefore, the spherical surface treatment method of the present invention can be suitably applied.

  In the spherical body surface treatment method according to one aspect of the present invention, the surface treatment may be a plasma nitriding treatment. In plasma nitriding, since the temperature control of the spherical body is important, the surface treatment method of the spherical body of the present invention can be particularly suitably applied.

  The manufacturing method of the spherical component in one aspect of the present invention includes a step of preparing a spherical molded body and a step of performing a surface treatment of the molded body. And the said surface treatment is implemented using the surface treatment method of the spherical body in one situation of the said invention.

  According to the method for manufacturing a spherical component in one aspect of the present invention, the spherical body of the present invention that enables surface treatment to be performed on the entire surface while accurately grasping the temperature of the spherical body. By performing the surface treatment using this surface treatment method, it is possible to manufacture a spherical component that has been successfully subjected to the surface treatment.

  In the method for manufacturing a spherical component according to one aspect of the present invention, the spherical component may be a rolling element of a rolling bearing. The method for manufacturing a spherical component of the present invention that can manufacture a spherical component that has been satisfactorily surface-treated is suitable as a method for manufacturing a rolling element of a rolling bearing in which the quality of the entire surface is important.

  The spherical surface treatment jig according to another aspect of the present invention is disposed so as to surround each of the plurality of concave portions and the plurality of concave portions that hold the spherical body in a rollable manner, and restricts movement of the spherical body. And a protrusion.

  In the spherical body surface treatment jig in the other aspect described above, a single spherical body can be placed in each of the recesses to support a plurality of spherical bodies. Thereby, even when each spherical body is rolled in the recess and the contact portion with the jig is changed in order to perform the surface treatment on the entire surface, the distance between the spherical bodies is appropriately maintained. Can do. As a result, by using the surface treatment jig according to another aspect of the present invention, normal surface treatment can be performed on the entire surface of the plurality of spherical bodies.

  In the spherical surface treatment jig in another aspect described above, the concave portion may have a shape in which the depth gradually increases toward a region where the depth of the concave portion is the greatest. Thereby, while a spherical body can roll smoothly in a recessed part, it becomes possible to keep appropriately the space | interval of spherical bodies more reliably. In addition, as a concrete shape of the recessed part which satisfy | fills such conditions, a mortar shape, the shape where a wall surface is a spherical surface, etc. can be selected, for example.

  In the spherical surface treatment jig according to the other aspect described above, the concave portion has a planar portion that holds the spherical body, and the projecting portion projects from the planar portion and surrounds the planar portion. Also good. Thereby, while a spherical body can roll smoothly in a recessed part, ensuring of the space | interval of the spherical bodies by a protrusion part can be made more reliable.

  In the spherical surface treatment jig according to the other aspect described above, the plurality of recesses are preferably arranged at intervals of at least twice the diameter of the spherical body. This makes it possible to maintain a sufficient interval between the spherical bodies. As a result, even when a surface treatment such as plasma nitriding is applied between the spherical body and another member, the generation of hollow cathodes between the spherical bodies can be more reliably suppressed. .

  In the spherical surface treatment jig according to the other aspect, preferably, the concave portions are arranged at equal intervals. Thereby, it becomes possible to arrange many recessed parts densely in the jig for surface treatment, and it can contribute to the improvement of the efficiency of surface treatment.

  The spherical body surface treatment method according to another aspect of the present invention includes placing one spherical body in each of the concave portions of the spherical body surface treatment jig according to another aspect of the present invention. A step of supporting a plurality of spherical bodies with a tool, and a step of performing a surface treatment on the plurality of spherical bodies supported by a jig.

  In the spherical body surface treatment method according to another aspect of the present invention, a plurality of spherical bodies are placed and supported on each of the recesses. Therefore, even when each spherical body is rolled in the recess to change the contact portion with the jig in order to carry out the surface treatment on the entire surface, the distance between the spherical bodies can be appropriately maintained. it can. As a result, according to the spherical surface treatment method in another aspect of the present invention, normal surface treatment can be performed on the entire surface of the plurality of spherical bodies.

  In the spherical body surface treatment method according to the other aspect described above, in the step of performing the surface treatment on the plurality of spherical bodies, the surface treatment may be performed while moving the spherical bodies relative to the jig. Good.

  Thereby, since the surface treatment is performed while changing the region in contact with the jig in the spherical body, the surface treatment can be efficiently performed on the entire surface of the spherical body.

  In the spherical body surface treatment method according to the other aspect described above, the step of performing the surface treatment on the plurality of spherical bodies includes the step of performing the surface treatment of the spherical body while supporting the first region of the spherical body with the jig. And a step of performing the surface treatment of the spherical body while supporting the second region different from the first region of the spherical body by the jig.

  Thus, in the step of performing the surface treatment, first, the surface treatment of the spherical body is performed while supporting the first region of the spherical body with the jig. At this time, since the first region of the spherical body is supported by the jig and is stationary, the temperature of the spherical body can be accurately measured and grasped. Thereafter, the surface treatment of the spherical body is performed while supporting the second region of the spherical body with a jig. At this time, since the second region of the spherical body is supported by the jig and is stationary, the temperature of the spherical body can be accurately measured and grasped. Moreover, since the contact area | region with the jig | tool in a spherical body can be changed with the case where it is supported in the 1st area | region and the case where it is supported in a 2nd area | region, it can cover the whole surface of a spherical body. The surface treatment can be performed on the surface. As a result, the surface treatment can be performed on the entire surface while accurately grasping the temperature of the spherical body.

  Preferably, in the spherical body surface treatment method in the other aspect described above, the step of performing the surface treatment while supporting the second region is after the step of performing the surface treatment while supporting the first region. Prior to this, the method further includes a step of moving the spherical body relative to the jig from a position supported in the first region to a position supported in the second region.

  Thereby, it becomes possible to change easily the area | region supported by a jig | tool in a spherical body, and surface treatment can be efficiently implemented with respect to the whole surface.

  In the spherical body surface treatment method in the other aspect, preferably, in the step of performing the surface treatment on the plurality of spherical bodies, the surface treatment is performed while measuring the temperature of the spherical bodies.

  Thereby, since it becomes possible to implement surface treatment, controlling the temperature of a spherical body appropriately, the speed and quality of desired surface treatment can be obtained stably.

  In the spherical body surface treatment method in the other aspect described above, the spherical body is made of a conductor, and in the step of performing the surface treatment on the spherical body, the spherical body and the spherical body are opposed to each other. The spherical body may be subjected to a surface treatment while a voltage is applied to the member.

  In surface treatment performed while a voltage is applied between a spherical body and a member arranged opposite to the spherical body, for example, plasma nitriding, plasma carburizing, PVD, CVD, etc., a plurality of spherical bodies are used. When performing the surface treatment at the same time, if the spacing between the spherical bodies is not properly maintained, or if the spherical bodies are in contact with each other, normal surface treatment may not be performed. For this reason, it is desirable that the above processing is performed while the interval between the spherical bodies is appropriately maintained. Therefore, the surface treatment method for a spherical body according to another aspect of the present invention described above is suitable for a surface treatment that is performed while a voltage is applied between the spherical body and a member disposed opposite to the spherical body. Can be applied to.

  In the spherical body surface treatment method according to the other aspect described above, the surface treatment may be a plasma nitriding treatment. When plasma nitriding is performed on a plurality of spheres, it is important to appropriately maintain the spacing between the spheres. Therefore, the surface treatment method for spheres according to another aspect of the present invention is particularly preferable. Can be applied.

  The manufacturing method of the spherical component in the other situation of this invention is equipped with the process of preparing a spherical molded object, and the process of implementing the surface treatment of a molded object. And the said surface treatment is implemented using the surface treatment method of the spherical body in the other situation of the said invention.

  According to the method for manufacturing a spherical component in another aspect of the present invention, the surface treatment can be performed on the entire surface while appropriately maintaining the interval between the plurality of spherical bodies. By performing the surface treatment using the spherical body surface treatment method in the above aspect, it is possible to manufacture a spherical component that has been favorably subjected to the surface treatment.

  In the method for manufacturing a spherical component in the other aspect described above, the spherical component may be a rolling element of a rolling bearing. The method for manufacturing a spherical component in another aspect of the present invention that can manufacture a spherical component that has been satisfactorily surface-treated is suitable as a method for manufacturing a rolling element of a rolling bearing in which the quality of the entire surface is important. is there.

  A spherical body surface treatment jig according to another aspect of the present invention includes a first holding member having a plurality of through-holes and a second holding section having a plurality of protrusions having a holding region for holding the spherical body at a tip portion. And a member. The first holding member and the second holding member have a structure in which each of the plurality of protrusions can penetrate each of the plurality of through holes.

  In the spherical surface treatment jig according to another aspect of the present invention, the first holding member and the second holding member are combined such that each of the plurality of protrusions penetrates each of the plurality of through holes. In the state, the spherical bodies can be held by the second holding member by placing one spherical body on each of the holding areas of the plurality of protrusions (first holding state). Moreover, the jig for surface treatment of a spherical body of the present invention supports the spherical body one by one in each of the plurality of through holes in a state in which the protruding portion is detached from the through hole, and thereby the first holding member A plurality of spherical bodies can be held (second holding state). Therefore, by using the spherical surface treatment jig in another aspect of the present invention, the surface treatment can be carried out in the following procedure.

  First, the surface treatment is performed while holding the spherical body in one of the first holding state and the second holding state. At this time, since the spherical body is held by either the outer peripheral portion of the through hole of the first holding member or the holding area of the second holding member, the temperature of the spherical body can be accurately measured and grasped. . Next, the surface treatment is performed while holding the spherical body in the other holding state of the first holding state and the second holding state. Also at this time, since the spherical body is held by the outer peripheral portion of the through hole of the first holding member and the other holding region of the second holding member, the temperature of the spherical body can be accurately measured and grasped. Further, since the contact area of the spherical body with the surface treatment jig can be changed between the first holding state and the second holding state, the surface treatment is performed on the entire surface of the spherical body. It becomes possible. As described above, according to the spherical body surface treatment jig according to another aspect of the present invention, it is possible to perform surface treatment on the entire surface while accurately grasping the temperature of the spherical body. A spherical surface treatment jig can be provided.

  In the spherical surface treatment jig according to another aspect described above, preferably, the first holding member further includes a guide hole penetrating the first holding member, and the second holding member is a guide penetrating the guide hole. It further includes a part.

  Accordingly, since the relative positional relationship between the first holding member and the second holding member can be guided, the spherical body is held by one of the first holding member and the second holding member, and the spherical body is held by the other. The transition to can be easily realized. From the viewpoint of facilitating the transition, the first holding member has a plurality of guide holes penetrating the first holding member, and the second holding member has a plurality corresponding to the plurality of guide holes. It is more preferable that the guide part is included.

  Preferably, the spherical surface treatment jig according to another aspect further includes a support member that supports the first holding member in a state in which the protruding portion does not penetrate the through hole. Thereby, the state in which the spherical body is held by the first holding member can be easily stabilized.

  In the spherical body surface treatment jig according to another aspect, preferably, the plurality of through holes are arranged at intervals of twice or more the diameter of the spherical body.

  This makes it possible to maintain a sufficient interval between the spherical bodies. As a result, even when a surface treatment such as plasma nitriding is applied between the spherical body and another member, the generation of hollow cathodes between the spherical bodies can be more reliably suppressed. .

  In the spherical surface treatment jig in another aspect described above, preferably, the through holes are arranged at equal intervals. As a result, a large number of through holes can be densely arranged in the surface treatment jig, which can contribute to an improvement in the surface treatment efficiency.

  The surface treatment method of a spherical body in another aspect of the present invention includes a step of holding a plurality of spherical bodies by the second holding member in the other aspect, and a plurality of spherical bodies held by the second holding member. Performing the surface treatment, performing the surface treatment on the plurality of spherical bodies held by the first holding member, and holding the plurality of spherical bodies by the first holding member in the other aspect. Process. In the step of holding the plurality of spherical bodies with the second holding member, in the surface treatment jig for the spherical body, the plurality of protrusions with each of the plurality of protrusions penetrating the plurality of through holes. A plurality of spherical bodies are held by the second holding member by placing one spherical body on each of the holding regions of the part. Further, in the step of holding the plurality of spherical bodies by the first holding member, the spherical bodies are supported one by one in each of the plurality of through holes in a state where the protruding portions are separated from the through holes. A plurality of spherical bodies are held by one holding member.

  In the spherical body surface treatment method according to another aspect of the present invention, the spherical body is subjected to the surface treatment while being held at the outer peripheral portion of the through hole of the first holding member, and the second holding member is held. Surface treatment is performed even in a state held by the region. Here, with respect to the spherical body, the surface treatment jig is either in the state of being held by the first holding member and being heat-treated or in the state of being held by the second holding member and being heat-treated. There is no need to exercise. Therefore, the surface treatment can be performed while accurately measuring and grasping the temperature of the spherical body. In addition, since the contact area of the spherical body with the surface treatment jig can be changed between the state of being held by the first holding member and the state of being held by the second holding member, the surface of the spherical body Surface treatment can be performed on the entire area. As described above, according to the spherical body surface treatment method according to another aspect of the present invention, the spherical surface that enables the surface treatment to be performed on the entire surface while accurately grasping the temperature of the spherical body. A body surface treatment method can be provided.

  In the spherical body surface treatment method according to another aspect, the surface treatment is preferably performed while the temperature of the spherical body is measured.

  Thereby, since it becomes possible to implement surface treatment, controlling the temperature of a spherical body appropriately, the desired speed and quality of surface treatment can be obtained stably.

  In the spherical surface treatment method according to another aspect described above, the spherical body is assumed to be made of a conductor, and in the step of performing the surface treatment on the spherical body, the spherical body and the spherical body are disposed to face each other. The spherical body may be subjected to a surface treatment while a voltage is applied to the member.

  In surface treatment performed while applying a voltage between a spherical body and a member arranged opposite to the spherical body, such as plasma nitriding, plasma carburizing, PVD, CVD, etc., the temperature of the spherical body is grasped. However, it is desirable that the processing is performed. Therefore, the spherical surface treatment method according to another aspect of the present invention can be suitably applied.

  In the spherical surface treatment method according to another aspect described above, the surface treatment may be a plasma nitriding treatment. In plasma nitriding, since the temperature control of the spherical body is important, the surface treatment method of the spherical body in another aspect of the present invention can be particularly suitably applied.

  The manufacturing method of the spherical component in another situation of this invention is equipped with the process of preparing a spherical molded object, and the process of implementing the surface treatment of a molded object. And the said surface treatment is implemented using the surface treatment method of the spherical body in another situation of the said invention.

  According to the method for manufacturing a spherical component in another aspect of the present invention, the surface treatment can be performed on the entire surface while accurately grasping the temperature of the spherical body. By carrying out the surface treatment using the spherical body surface treatment method in, spherical parts that have been satisfactorily surface-treated can be produced.

  In the method for manufacturing a spherical component in another aspect described above, the spherical component may be a rolling element of a rolling bearing. The method for producing a spherical component according to another aspect of the present invention, which can produce a spherical component that has been satisfactorily surface-treated, is suitable as a method for producing a rolling element of a rolling bearing in which the quality of the entire surface is important. .

  As is apparent from the above description, according to the spherical surface treatment jig, the spherical surface treatment method, and the spherical component manufacturing method according to one aspect and another aspect of the present invention, the temperature of the spherical body It is possible to provide a spherical surface treatment jig, a spherical surface treatment method, and a spherical part manufacturing method that enable surface treatment to be performed on the entire surface while accurately grasping .

  In addition, according to the spherical surface treatment jig, the spherical surface treatment method, and the spherical component manufacturing method according to another aspect of the present invention, normal surface treatment is performed on the entire surface of a plurality of spherical bodies. It is possible to provide a spherical surface treatment jig, a spherical surface treatment method, and a spherical part manufacturing method that can be implemented.

3 is a flowchart showing an outline of a method for manufacturing a spherical component in the first embodiment. FIG. 3 is a schematic cross-sectional view showing a configuration of a spherical surface treatment jig in the first embodiment. 2 is a schematic plan view showing a configuration of a holding plate in Embodiment 1. FIG. FIG. 5 is a schematic cross-sectional view for illustrating a surface treatment process in the first embodiment. FIG. 5 is a schematic cross-sectional view for illustrating a surface treatment process in the first embodiment. FIG. 5 is a schematic cross-sectional view for illustrating a surface treatment process in the first embodiment. FIG. 5 is a schematic cross-sectional view for illustrating a surface treatment process in the first embodiment. FIG. 5 is a schematic cross-sectional view for illustrating a surface treatment process in the first embodiment. It is a schematic plan view which shows the 1st modification of a holding plate. It is a schematic plan view which shows the 2nd modification of a holding plate. 6 is a flowchart showing an outline of a method for manufacturing a spherical component in a second embodiment. 6 is a schematic plan view showing the configuration of a spherical surface treatment jig in Embodiment 2. FIG. It is a schematic sectional drawing in alignment with line segment XIII-XIII of FIG. 10 is a flowchart showing an outline of a method for manufacturing a spherical component in a third embodiment. 10 is a schematic plan view showing the configuration of a spherical surface treatment jig in Embodiment 4. FIG. It is a schematic sectional drawing in alignment with line segment XVI-XVI of FIG. 10 is a flowchart showing an outline of a method for manufacturing a spherical component in a fifth embodiment. FIG. 10 is a schematic plan view showing the configuration of a spherical surface treatment jig in a fifth embodiment. FIG. 10 is a schematic cross-sectional view for illustrating a surface treatment step in a fifth embodiment. FIG. 10 is a schematic cross-sectional view for illustrating a surface treatment step in a fifth embodiment. FIG. 10 is a schematic cross-sectional view for illustrating a surface treatment step in a fifth embodiment. FIG. 10 is a schematic cross-sectional view for illustrating a surface treatment process in a sixth embodiment. It is a figure which shows the experimental result of Example 1.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
First, Embodiment 1 which is an embodiment corresponding to one aspect of the present invention will be described. Referring to FIG. 1, in the method for manufacturing a spherical component in the first embodiment, first, a spherical body preparation step is performed as a step (S10). Specifically, in the step (S10), for example, a molded body that is molded into the shape (spherical) of a rolling element of a rolling bearing (ball of a ball bearing) and subjected to quenching and tempering processing is prepared. As the material of the molded body, for example, steel, AMS standard 5630 (AISI standard 440C, JIS standard SUS440C), AMS standard 6490 (AISI standard M50), AMS standard 5626 (AISI standard T1, JIS standard SKH2), etc. should be adopted. Can do.

  Next, as steps (S20) to (S50), a surface treatment step for carrying out a surface treatment of the spherical molded body prepared in step (S10) is performed. In the present embodiment, plasma nitridation is performed as the surface treatment. Specifically, first, a first support step is performed as a step (S20). In this step (S20), the molded body is supported by the spherical surface treatment jig in the first embodiment disposed inside the processing chamber for performing plasma nitriding. Here, the spherical surface treatment jig in Embodiment 1 will be described.

  Referring to FIGS. 2 and 3, jig 1 as a surface treatment jig for a spherical body in the first embodiment has a disk shape and a plurality of through holes 11 having a circular cross section are formed. The first holding plate 10 as the first holding member, and the second holding member having a disk-like shape like the first holding plate 10 and having a plurality of through holes 21 having a circular cross section. As a fixing member that fixes the relative positional relationship between the first holding plate 10 and the second holding plate 20 by sandwiching the second holding plate 20, the first holding plate 10, and the second holding plate 20. The clamp 30 and the support member 40 that supports the jig 1 are provided. The clamp 30 may be capable of being fixed to the first holding plate 10 and the second holding plate 20 with, for example, a screw or a universal joint. In FIG. 3, the first holding plate 10 is shown as a representative of the two holding plates, but the second holding plate 20 has the same structure as the first holding plate.

  Next, a specific procedure of the step (S20) using the jig 1 will be described. Referring to FIG. 4, in step (S20), first, first holding plate 10 is supported by support member 40 and arranged on bottom wall 90 of the processing chamber for performing the surface treatment. Next, in each of the through holes 11 of the first holding plate 10, a plurality of molded bodies are supported by the first holding plate 10 by supporting the molded bodies 91 as spherical bodies prepared in the step (S <b> 10) one by one. 91 is held.

  Next, a first plasma nitriding step is performed as a step (S30). In this step (S30), for example, a spherical molded body 91 made of AMS6490 is plasma-nitrided. Specifically, in the step (S20), the molded body 91 supported by the first holding plate 10 of the jig 1 has a discharge voltage of 50 V or more in a mixed gas atmosphere of nitrogen and hydrogen having a pressure of 50 Pa to 1000 Pa, for example. Plasma nitridation is performed by cooling to 600 V or less and a discharge current of 0.001 A to 300 A in a temperature range of 350 ° C. to 500 ° C. for 1 hour to 50 hours and then cooling. Further, in the step (S30), the temperature of the molded body 91 is measured, the molded body 91 is adjusted so that the temperature falls within the above range, and the discharge voltage and discharge current within the above range are achieved. The plasma nitriding treatment of the molded body 91 is performed while a voltage is applied between 91 and an electrode which is a member disposed to face the molded body 91.

  Next, a 2nd support process is implemented as process (S40). In this step (S40), referring to FIG. 5, first, as the second holding member, the through hole 11 of the first holding plate 10 and the through hole 21 of the second holding plate 20 are positioned corresponding to each other. The second holding plate 20 is arranged along the first holding plate 10. Thereafter, by bringing the second holding plate 20 closer to the first holding plate 10, the plurality of molded bodies 91 on which the plasma nitriding treatment has been performed in the step (S 30) are held between the first holding plate 10 and the second holding plate 20. Is done. Furthermore, when the clamp 30 is fitted into the end portions of the first holding plate 10 and the second holding plate 20, a force is applied to reduce the distance between the first holding plate 10 and the second holding plate 20. The relative positional relationship between the first holding plate 10 and the second holding plate 20 is fixed. Then, the positional relationship between the first holding plate 10 and the second holding plate 20 is reversed while the molded body 91 is sandwiched between the first holding plate 10 and the second holding plate 20 as indicated by an arrow α. Then, it is placed on the support member 40 as shown in FIG.

  Thereafter, the clamp 30 is removed as shown in FIG. 7 to release the positional relationship between the first holding plate 10 and the second holding plate 20, and the first holding plate 10 is formed as shown in FIG. Remove from 91. Thereby, one molded body 91 is supported in each of the through holes 21 of the second holding plate 20. At this time, the molded body 91 is held by the second holding plate 20 in a state in which a region different from the case of being held by the first holding plate 10 is in contact with the second holding plate 20.

  Next, a second plasma nitriding step is performed as a step (S50). In this step (S50), plasma nitriding treatment of the molded body 91 is performed in the same manner as in the step (S30) except that the molded body 91 is supported by the second holding plate 20 as shown in FIG. Through the above steps, the surface treatment step in the first embodiment is completed. And the manufacturing method of the rolling element of the rolling bearing as a spherical component in Embodiment 1 is completed by performing the finishing process in which surface grinding | polishing etc. are implemented as needed after that.

  In the spherical surface treatment method using the jig 1 as the spherical surface treatment jig in the present embodiment and the rolling bearing rolling element production method as the spherical component, the molded body 91 is The plasma nitriding process is performed while being held in the through hole 11 of the first holding plate 10, and the surface treatment is also performed while being held in the through hole 21 of the second holding plate 20. Here, with respect to the molded body 91, the jig 91 is in a state of being held by the first holding plate 10 and being heat-treated and a state of being held by the second holding plate 20 and being heat-treated. There is no need to exercise. Therefore, plasma nitriding can be performed while accurately measuring and grasping the temperature of the molded body 91. Moreover, since the contact area | region with the jig | tool 1 in the molded object 91 can be changed with the state currently hold | maintained by the 1st holding plate 10 and the state hold | maintained by the 2nd holding plate 20, the molded object 91 is changed. Surface treatment can be performed on the entire surface of the surface. As a result, according to the plasma nitriding method in the present embodiment, the nitriding treatment can be performed on the entire surface while accurately grasping the temperature of the molded body 91.

  Therefore, according to the spherical body surface treatment method using jig 1 as a spherical surface treatment jig in the present embodiment and the rolling element rolling element production method as a spherical component, While the temperature of a certain molded body 91 is accurately grasped, plasma nitriding is performed on the entire surface, and a rolling element of a rolling bearing that is satisfactorily surface-treated can be manufactured.

  In the above embodiment, the case where the surface treatment (plasma nitriding treatment) is performed twice on the spherical body (molded body 91) has been described. For example, after the step (S50), the first holding plate 10 is used. Further, by repeating the same process as the steps (S20) and (S30) using the clamp 30 again, it may be performed three or more times as necessary.

  In addition, the through holes 11 of the first holding plate 10 and the through holes 21 of the second holding plate 20 in the present embodiment are preferably arranged at an interval of at least twice the diameter of the molded body 91. Thereby, it becomes possible to maintain the space | interval of the molded object 91 enough, and generation | occurrence | production of a hollow cathode can be suppressed more reliably. In order to further suppress the generation of the hollow cathode, it is desirable that the through holes 11 and 21 are arranged at intervals of 5 times or more the diameter of the molded body 91.

  Furthermore, it is preferable that the through-holes 11 and 21 are arrange | positioned at equal intervals. As a result, a large number of through holes 11 and 21 can be densely arranged in the first holding plate 10 and the second holding plate 20, and the number of molded bodies 91 that can be heat-treated can be increased at the same time. As a result, the efficiency of the surface treatment can be improved.

  Further, in the first embodiment, the case where the first holding plate 10 and the second holding plate 20 have the through holes 11 and 21 having a circular cross-sectional shape and a planar holding plate having a circular shape has been described. However, the structure of the first holding member and the second holding member in one aspect of the present invention is not limited to this. In particular. For example, the cross-sectional shape of the through holes 11 and 21 may be circular as shown in FIG. 9, or may be a polygonal shape (triangular shape) as shown in FIG. Further, the planar shape of the first holding plate 10 and the second holding plate 20 may be a rectangular shape as shown in FIG. 9, or may be a disk shape (doughnut shape) having a hole in the center, For the purpose of facilitating handling, the donut-shaped shape may be cut in the radial direction and divided into a plurality of parts, so that the shape near the center of the sector shape may be omitted as shown in FIG. That is, the planar shape of the first holding plate 10 and the second holding plate 20 can adopt various shapes in consideration of the shape of the processing chamber for carrying out the surface treatment, ease of handling, and the like. And as long as the cross-sectional shape of the through-holes 11 and 21 is a shape which can hold | maintain a spherical body, arbitrary shapes are employable. In addition, as the first holding member and the second holding member of the present invention, a lattice-like net-like member can be adopted instead of the plate-like member. In this case, it is necessary to make the lattice spacing smaller than the diameter of the spherical body.

(Embodiment 2)
Next, Embodiment 2 which is an embodiment corresponding to the other aspect of the present invention will be described. Referring to FIG. 11, in the method of manufacturing a spherical component in the second embodiment, first, a spherical body preparation step is performed as a step (S110). This step (S110) can be performed in the same manner as the step (S10) of the first embodiment.

  Next, as steps (S120) to (S130), a surface treatment step for carrying out a surface treatment of the spherical molded body prepared in step (S110) is performed. In the present embodiment, plasma nitridation is performed as the surface treatment. Specifically, a support process is first implemented as process (S120). In this step (S120), the compact is supported by the spherical surface treatment jig in the second embodiment placed inside the processing chamber for performing plasma nitriding. Here, the spherical surface treatment jig in Embodiment 2 will be described.

  Referring to FIGS. 12 and 13, jig 101 as a spherical surface treatment jig in the second embodiment includes a flat base plate 110, and the base plate 110 has a wall surface. A plurality of concave portions 112 having a spherical shape and a protruding portion 111 disposed so as to surround each of the plurality of concave portions 112 are formed. The recess 112 has a function of holding the molded body 91. Further, the radius of curvature of the wall surface of the concave portion 112 is sufficiently larger than the radius of the spherical molded body 91 as a spherical body, and the molded body 91 can roll inside the concave portion 112. On the other hand, the protrusion 111 has a sufficient height from the region where the depth of the recess 112 is the largest, so that even if the molded body 91 rolls in the recess 112, it does not jump out of the recess 112. And has a function of restricting the movement of the molded body 91. Various shapes can be adopted as the shape of the base plate 110. For example, the base plate 110 may have a disk shape (doughnut shape) having a hole in the center, or the donut shape for easy handling. This shape may be cut in the radial direction and divided into three equal parts, so that the shape near the center of the sector shape may be omitted as shown in FIG.

  Next, a specific procedure of the step (S120) using the jig 101 will be described. Referring to FIGS. 12 and 13, first, spherical shaped bodies 91 prepared in step (S <b> 110) are placed one by one in each recess 112 of jig 101. And the jig | tool 101 with which the molded object 91 was mounted is inserted in the processing chamber of the plasma nitriding furnace in which plasma nitriding is implemented. Accordingly, the plurality of molded bodies 91 are supported in the processing chamber by the jig 101.

  Next, referring to FIG. 11, a plasma nitriding step is performed as a step (S130). In this step (S130), for example, a spherical molded body 91 made of AMS6490 is plasma-nitrided. Specifically, the molded body 91 supported by the jig 101 in the step (S120) has a discharge voltage of 50 V to 600 V and a discharge current of 0.1 V in a mixed gas atmosphere of nitrogen and hydrogen at a pressure of 50 Pa to 1000 Pa. After being held in a temperature range of 350 ° C. to 500 ° C. for 1 hour to 50 hours under conditions of 001 A to 300 A, plasma nitriding is performed by cooling. Through the above steps, the surface treatment step in Embodiment 2 is completed. And the manufacturing method of the rolling element of the rolling bearing as a spherical component in Embodiment 2 is completed by performing the finishing process in which surface grinding | polishing etc. are implemented as needed after that.

  Here, the surface treatment method of the spherical body (molded body 91) using the jig 101 as the surface treatment jig of the spherical body in the present embodiment, and the method of manufacturing the rolling element of the rolling bearing as the spherical component Accordingly, in the step (S130), at least one of the swinging, vibration, and intermittent rotation is applied to the jig 101. Thereby, the plasma nitriding process is performed while the molded body 91 moves (rolls) relative to the jig 101. As a result, the plasma nitriding process is performed while changing the region in contact with the jig 101 in the molded body 91, so that the plasma nitriding process can be efficiently performed on the entire surface of the molded body 91. In addition, since the molded bodies 91 are held one by one by the concave portions 112 of the jig 101, even when each molded body 91 rolls in the concave portions 112 as described above, the interval between the molded bodies 91 is reduced. Can be kept appropriate. Therefore, a hollow cathode is generated between the molded bodies 91, the temperature of the molded bodies is increased, and a phenomenon in which the nitriding depth is partially increased can be suppressed. As a result, a spherical body (molded body) subjected to good plasma nitriding treatment is obtained, and a rolling element (ball) of a rolling bearing having high quality can be manufactured.

  Here, it is desirable that the recesses 112 of the jig 101 in the present embodiment are arranged at an interval of at least twice the diameter of the molded body 91. Thereby, it becomes possible to maintain the space | interval of the molded object 91 enough, and generation | occurrence | production of a hollow cathode can be suppressed more reliably. In order to further suppress the generation of the hollow cathode, it is desirable that the recesses 112 are arranged at intervals of 5 times or more the diameter of the molded body 91.

  In addition, the recesses 112 of the jig 101 in the present embodiment are preferably arranged at equal intervals. Thereby, it becomes possible to arrange many recessed parts 112 densely in the jig | tool 101, and it can contribute to the efficiency improvement of surface treatment.

  Furthermore, in the step (S130) in the present embodiment, it is preferable that the plasma nitriding process is performed while the temperature of the molded body 91 is measured. Thereby, the speed and quality of a desired plasma nitriding process can be obtained stably. Here, in the present embodiment, since the range of movement of the molded body 91 in the step (S130) is limited to the inside of the recess 112 of the jig 101, the temperature of the molded body 91 can be easily measured.

(Embodiment 3)
Next, Embodiment 3 which is another embodiment corresponding to the other aspect of the present invention will be described. Referring to FIG. 14 and FIG. 11, the spherical surface treatment method using the spherical surface treatment jig in Embodiment 3 and the method of manufacturing a rolling element of a rolling bearing as a spherical component are basically described. Is implemented in the same manner as in the second embodiment, and has the same effect. However, in place of the plasma nitridation step performed as the step (S130) in the second embodiment, in the third embodiment, the first plasma nitridation step (S131) and the second plasma nitridation step (S132) are performed. This is different from the second embodiment in that step (S140), which is a spherical body moving step, is performed between steps (S131) and (S132).

  That is, in the method for manufacturing a spherical component in the third embodiment, first, steps (S110) and (S120) are performed in the same manner as in the second embodiment. Next, a first plasma nitriding step is performed as a step (S131). In this step (S131), plasma nitriding is performed basically in the same manner as in step (S130) of the second embodiment. However, in the step (S131), unlike the step (S130) of the second embodiment, the jig 101 is not subjected to movement such as swing, vibration, intermittent rotation, etc. Plasma nitriding is performed with the molded body 91 stationary.

  Next, a spherical body movement process is implemented as process (S140). In this step (S140), by rolling the molded body 91 relative to the jig 101, the molded body 91 is cured from the position supported in the first area to the position designated in the second area. Move relative to the tool 101. Specifically, referring to FIG. 12 and FIG. 13, in the step (S140), the angle formed by the back surface 113 of the jig 101 arranged in the processing chamber of the plasma nitriding furnace with the horizontal plane is the step (S131). The jig 101 is tilted so as to be different. Thereby, the molded object 91 rolls in the recessed part 112, and the area | region which contacts the jig | tool 101 changes.

  In the surface treatment process of the molded body 91 in the present embodiment, as described above, first, in the step (S131), the first region of the molded body 91 is supported by the jig 101 while the surface treatment ( Plasma nitriding treatment) is performed. At this time, since the molded body 91 is stationary with the first region supported by the jig 101, the temperature of the molded body 91 can be accurately measured and grasped. Thereafter, in the step (S132), the plasma nitriding treatment of the molded body 91 is performed while the second region of the molded body 91 is supported by the jig 101. At this time, since the second region of the molded body 91 is supported by the jig 101 and is stationary, the temperature of the molded body 91 can be accurately measured and grasped. Moreover, since the contact area | region with the jig | tool 101 in the molded object 91 can be changed with the case where it is supported in the 1st area | region and the 2nd area | region, the surface of the molded object 91 is changed. Plasma nitriding treatment can be performed on the entire region. As a result, according to the process of the present embodiment, the plasma nitriding process can be performed on the entire surface while accurately grasping the temperature of the molded body 91.

(Embodiment 4)
Next, a fourth embodiment which is another embodiment corresponding to the other aspect of the present invention will be described. The spherical surface treatment method using the spherical surface treatment jig in the fourth embodiment and the method for manufacturing the rolling element of the rolling bearing as the spherical component are basically the same as those in the second embodiment. The same effect is achieved. However, the jig 102 in the fourth embodiment is different from that in the second embodiment in the shapes of the recesses and the protrusions.

  That is, referring to FIGS. 15 and 16, jig 102 as a surface treatment jig for a spherical body in the fourth embodiment includes a flat base plate 121, and the base plate 121 includes a rectangular parallelepiped. A plurality of concave portions 123 having a shape, and projecting portions 122 that protrude from the bottom surfaces 123A of the plurality of concave portions 123 and are arranged so as to surround each of the bottom surfaces 123A are formed. The bottom surface 123A has a quadrangular (square) shape, for example, as shown in FIGS. 15 and 16, and is arranged in a matrix. And the protrusion part 122 is arrange | positioned as a wall surrounding each of the said bottom face 123A. The concave portion 123 has a function of holding a molded body 91 that is a spherical body. Further, the length of one side of the bottom surface 123 </ b> A having a square shape is sufficiently larger than the diameter of the molded body 91, and the molded body 91 can roll inside the recess 123. On the other hand, the protruding portion 122 protrudes with a sufficient height from the bottom surface 123A, and even when the molded body 91 rolls in the concave portion 123, the movement of the molded body 91 is restricted so as not to jump out of the concave portion 123. It has a function to do. As the planar shape of the base plate 121, various shapes can be selected as in the case of the second embodiment.

  And the surface treatment method of the spherical body in this Embodiment and the manufacturing method of the rolling element of the rolling bearing as a spherical component are the above-mentioned Embodiment 2 or implementation using the jig | tool 102 in this Embodiment. It can be implemented in the same manner as in the third mode.

(Embodiment 5)
Next, Embodiment 5 which is an embodiment corresponding to another aspect of the present invention will be described with reference to FIGS. 19-21 has shown the cross section which follows the line segment AA of FIG.

  Referring to FIG. 17, in the method of manufacturing a spherical component in the fifth embodiment, first, a spherical body preparation step is performed as a step (S210). This step (S210) can be performed in the same manner as the step (S10) of the first embodiment.

  Next, as steps (S220) to (S250), a surface treatment step for carrying out the surface treatment of the spherical molded body prepared in step (S210) is performed. In the present embodiment, plasma nitridation is performed as the surface treatment. Specifically, first, a first support step is performed as a step (S220). In this step (S220), the molded body is supported by the spherical surface treatment jig according to the fifth embodiment placed inside the processing chamber for performing plasma nitriding. Here, the spherical surface treatment jig in the fifth embodiment will be described.

  Referring to FIGS. 18 and 19, a jig 201 as a spherical surface treatment jig in the fifth embodiment includes a first holding member 210 and a second holding member 220. The first holding member 210 includes a flat base plate 211, and a plurality of through holes 212 that penetrate the base plate 211 and guide holes 213 that penetrate the base plate 211 are formed in the base plate 211. Yes. The through holes 212 are arranged at equal intervals in the base plate 211. The guide holes 213 are formed at a plurality of locations (two locations in the present embodiment) of the base plate 211. As the planar shape of the through-hole 212, various shapes such as a polygonal shape, a circular shape, and an elliptical shape can be adopted. However, from the viewpoint of making it possible to stably hold the spherical body. It is preferable to form a circle having a diameter slightly smaller than the diameter of the power spherical body, or a regular polygon shape in which the diameter of the inscribed circle is slightly smaller than the diameter of the spherical body to be retained.

  On the other hand, the second holding member 220 has a plurality of protrusions 221 having a rod-like shape in which a spherical holding region 221A for holding a spherical body is formed at the tip, and a rod-like shape longer than the protrusion 221. And a guide bar 222 as a guide member. The plurality of protrusions 221 are arranged at equal intervals corresponding to the interval between the through holes 212 of the base plate 211 and protrude in parallel with each other. Further, the guide rod 222 is formed at a plurality of locations (two locations in the present embodiment) corresponding to the guide holes 213 of the base plate 211, and is arranged in parallel with the protruding portion 221. Various shapes can be adopted as the shape of the base plate 211. For example, the base plate 211 may have a disk shape (doughnut shape) having a hole in the center, or the donut shape for easy handling. As shown in FIG. 18, the shape near the center may be omitted as shown in FIG.

  Next, a specific procedure of the step (S220) using the jig 201 will be described. In the step (S220), the first holding member 210 and the second holding member 220 are arranged such that each of the plurality of projecting portions 221 passes through each of the plurality of through holes 212, as shown in FIGS. Arranged in combination. Then, one molded body 91 as a spherical body prepared in the step (S210) is placed on each of the holding regions 221A of the protrusions 221 penetrating the through holes 212. As a result, the plurality of molded bodies 91 are held by the second holding member 220. Then, the jig 201 on which the molded body 91 is placed is placed in a processing chamber of a plasma nitriding furnace in which plasma nitriding is performed, and is disposed on a support region 231 that supports the jig 201 in the processing chamber. Accordingly, the plurality of molded bodies 91 are supported in the processing chamber by the jig 201.

  Next, referring to FIG. 17, a first plasma nitriding step is performed as a step (S230). In this step (S230), for example, a spherical molded body 91 made of AMS6490 is plasma-nitrided. Specifically, in the step (S220), the molded body 91 supported by the jig 201 has a discharge voltage of 50 V to 600 V and a discharge current of 0.1 V in a mixed gas atmosphere of nitrogen and hydrogen at a pressure of 50 Pa to 1000 Pa. After being held in a temperature range of 350 ° C. to 500 ° C. for 1 hour to 50 hours under conditions of 001 A to 300 A, plasma nitriding is performed by cooling. In the step (S230), the temperature of the molded body 91 is measured, the molded body is adjusted so that the temperature falls within the above range, and the discharge voltage and discharge current within the above range are achieved. The plasma nitriding treatment of the molded body 91 is performed while a voltage is applied between 91 and an electrode which is a member disposed to face the molded body 91.

  Next, a 2nd support process is implemented as process (S240). In this step (S240), the first holding member 210 of the jig 201 is moved toward the side away from the support region 231 that supports the jig 201 (the side away from the second holding member 220). Thereby, as shown in FIG. 20, the protruding portion 221 of the second holding member 220 is detached from the through hole 212 of the first holding member 210. As a result, the plurality of molded bodies 91 are held by the first holding member 210 by supporting the molded bodies 91 one by one in each of the plurality of through holes 212. At this time, the movement of the first holding member 210 relative to the second holding member 220 is guided by the guide bar 222 parallel to the protruding portion 221 and the guide hole 213 formed in the base plate 211. Therefore, the rolling of the molded body 91 is suppressed when the member holding the molded body 91 moves from the protruding portion 221 to the base plate 211. As a result, it is possible to reliably avoid the overlap between the region in contact with the protruding portion 221 and the region in contact with the base plate 211 in the molded body 91.

  Furthermore, as shown in FIG. 21, the first holding member 210 is supported by the support member 223 while the molded body 91 is held by the first holding member 210, and the protruding portion 221 does not penetrate the through hole 212. 2 The protrusion 221 of the holding member 220 is removed. The support member 223 may have various shapes. For example, when the guide bar 222 has a cylindrical shape, a through hole corresponding to the diameter of the guide bar 222 is formed as shown in FIG. The formed hollow cylindrical support column may be composed of two members divided by a cross section including the diameter of the bottom surface. Then, the support member 223 made of the two members is fitted into the guide rod 222 so that the inner peripheral surfaces of the two members are in contact with the outer peripheral surface of the guide rod 222, thereby the first holding member 210 by the support member 223. Support can be achieved. The reason why the protrusion 221 is removed in the step (S240) is to avoid the generation of a hollow cathode between the protrusion 221 and the molded body 91.

  Next, a second plasma nitriding step is performed as a step (S250). In this step (S250), plasma nitriding treatment of the molded body 91 is performed in the same manner as in the step (S230) except that the molded body 91 is supported by the first holding member 210 as shown in FIG. Through the above steps, the surface treatment step in the fifth embodiment is completed. And the manufacturing method of the rolling element of the rolling bearing as a spherical component in Embodiment 5 is completed by performing the finishing process in which surface grinding | polishing etc. are implemented after that as needed.

  In the spherical surface treatment method using the jig 201 as the spherical surface treatment jig in the present embodiment and the rolling bearing rolling element production method as the spherical component, in step (S230), Since the plasma nitriding is performed while the molded body 91 is held in the holding region 221A of the protruding portion 221, the temperature of the molded body 91 can be accurately measured and grasped. Thereafter, in the step (S240), the support state of the molded body 91 is changed from a state in which the molded body 91 is supported by the holding region 221A of the protruding portion 221 to a state in which the molded body 91 is supported by the through hole 212 of the base plate 211. Then, in the step (S250), plasma nitriding is performed while the molded body 91 is held in the through hole 212 of the base plate 211. Also at this time, since the molded body 91 is held in the through hole 212, the temperature of the molded body 91 can be accurately measured and grasped. Further, in the step (S230) and the step (S250), the contact area of the molded body 91 with the jig 201 can be changed, so that plasma nitriding can be performed on the entire surface of the molded body 91. it can.

  As a result, according to the spherical body surface treatment method using the jig 201 as the spherical surface treatment jig in the present embodiment and the rolling bearing rolling element production method as the spherical component, the spherical body The rolling body of the rolling bearing in which the plasma nitridation is performed on the entire surface while accurately grasping the temperature of the molded body 91 and the surface treatment is satisfactorily performed can be manufactured.

  In the present embodiment, the molded body 91 is first held by the second holding member 220 and the plasma nitriding process is performed, and then the molded body 91 is held by the first holding member 210 and further the plasma nitriding process is performed. In this embodiment, the molded body 91 is first held by the first holding member 210 and the plasma nitriding process is performed. Then, the molded body 91 is held by the second holding member 220 and the plasma nitriding process is further performed. May be adopted.

  In addition, it is desirable that the through holes 212 of the base plate 211 in the present embodiment are arranged at an interval of at least twice the diameter of the molded body 91. Thereby, it becomes possible to maintain the space | interval of the molded object 91 enough, and generation | occurrence | production of a hollow cathode can be suppressed more reliably. In order to further suppress the generation of the hollow cathode, it is desirable that the through holes 212 are arranged at intervals of 5 times or more the diameter of the molded body 91.

(Embodiment 6)
Next, Embodiment 6 which is another embodiment corresponding to another aspect of the present invention will be described. FIG. 22 corresponds to FIG. 21 in the fifth embodiment.

  The spherical surface treatment method using the spherical surface treatment jig in the sixth embodiment and the method of manufacturing the rolling element of the rolling bearing as the spherical component are basically the same as those in the fifth embodiment. The same effect is achieved. However, in the jig 201 in the sixth embodiment, the lengths of the guide rod 222 and the support member 223 are longer than those in the fifth embodiment, and accordingly, the procedure (S240) is performed in the fifth embodiment. Is partly different.

  Referring to FIG. 17, in the method of manufacturing a rolling element of a rolling bearing in the sixth embodiment, first, steps (S210) to (S230) are performed in the same manner as in the fifth embodiment. The step (S240) is basically performed in the same manner as in the fifth embodiment, but as described above, the lengths of the guide bar 222 and the support member 223 are longer than those in the fifth embodiment. long. Thus, when the first holding member 210 is supported by the support member 223, a sufficient distance is secured between the protruding portion 221 and the molded body 91 in order to avoid the occurrence of a hollow cathode. Therefore, in the step (S240) in the sixth embodiment, the step (S240) is completed without removing the protruding portion 221. Then, the manufacturing method of the rolling element of the rolling bearing according to the sixth embodiment is completed by performing a step (S250) and a finishing step in which the surface of the molded body 91 is polished as necessary.

  As described above, according to the method for manufacturing a rolling element of a rolling bearing in the sixth embodiment, the manufacturing process can be simplified as compared with the case of the fifth embodiment.

  Whether or not a good plasma nitriding treatment is performed on the spherical body (molded body 91) can be evaluated by the uniformity of the nitriding depth in the surface layer of the spherical body. Specifically, a value obtained by dividing the difference between the largest value and the smallest value of the nitriding depth in the surface layer of the spherical body by the largest value and multiplying by 100 (hereinafter, the difference in nitriding depth (%)) However, it is preferable that the uniformity of the nitriding depth is ensured to an extent of, for example, 50% or less.

  Here, the nitriding depth can be measured by methods such as measurement of hardness distribution in the cross section, measurement of nitrogen concentration distribution, and observation of the corrosion structure (microstructure) in the cross section.

  In the measurement of the hardness distribution in the cross section, for example, a spherical body that has been subjected to the plasma nitriding treatment is cut in a cross section (plane) perpendicular to the surface, and the hardness distribution is measured in the direction from the surface toward the center in the cross section. The thickness of a region having a hardness of a predetermined value or higher, or the thickness of a region having a hardness higher than a predetermined value with respect to the base material (non-nitrided region) can be considered as the nitriding depth.

  In the measurement of the nitrogen concentration distribution, for example, the nitrogen concentration distribution in the cross section of the spherical body similar to the measurement of the hardness distribution is investigated by EPMA (Electron Probe Micro Analyzer), and a predetermined concentration (for example, 0.1% by mass) or more. This thickness can be considered as the nitriding depth. The nitrogen concentration distribution may be measured by GDS (GD-OES) analysis (Glow Discharge Optical Emission Spectroscopy) while sputtering a sphere that has been subjected to plasma nitriding treatment in a direction perpendicular to the surface. it can.

  Furthermore, in the observation of the corrosive structure (micro structure) in the cross section, for example, the cross section of the spherical body similar to the measurement of the hardness distribution is corroded with a nital (nitric acid alcohol solution) having a nitric acid concentration of about 3 to 10% by mass. At this time, since the nitrided layer is deeply corroded (easily corroded) as compared with the base material, the corroded cross section is observed with an optical microscope or SEM (Scanning Electron Microscope) to determine the nitridation depth. Can be measured.

  Further, as the material constituting the spherical surface treatment jig of the present invention, various materials that can withstand the temperature of the surface treatment to be applied can be adopted. It is preferable to employ steel having a low alloy steel (for example, mild steel (JIS) with a low content of alloy elements in order to suppress adhesion of alloy elements contained in the steel to the spherical body by sputtering or the like. G3131), carbon steel (JIS G4051) and the like are preferably used as the material.

  Embodiment 1 of the present invention will be described below. Experiments were conducted to investigate the preferred spacing between spherical bodies in plasma nitriding. The experimental procedure is as follows.

  First, a plate made of S45C (JIS standard mechanical structural carbon steel) having a length of 60 mm, a height of 100 mm, and a thickness of 10 mm was prepared, charged into a processing chamber of a plasma nitriding furnace, and plasma nitriding was performed. The plasma nitriding was performed under the condition of heating to 450 ° C. and holding for 2 hours in a mixed atmosphere of nitrogen and hydrogen gas at a pressure of 200 to 300 Pa. At this time, two types of plasma nitridation were performed, in which only one plate was loaded and in which three plates were loaded. In either case, one plate was inserted separately for temperature control, and the output of the plasma nitriding furnace was adjusted so that the temperature of the temperature control plate was 450 ° C. Moreover, about the case where 3 sheets were inserted, the space | interval of the said board was changed 5 steps in the range of 5 mm-50 mm. And the temperature of the board was measured about each case.

  Next, the results of the experiment will be described with reference to FIG. In FIG. 23, the horizontal axis indicates the distance between the plates when three plates are inserted, and the vertical axis indicates the temperature of the plates. The circles indicate measured values of the plate temperature when three plates are loaded. Furthermore, the broken line has shown the measured value of the temperature of the board | plate when only one board is inserted.

  Referring to FIG. 23, when three plates are inserted so that the interval between the plates becomes 5 mm, the temperature of the plates rises to 1050 ° C. or higher. This is probably because the hollow cathode state was formed because the distance between the plates was small. Then, the temperature of the plates decreased as the interval between the plates increased, and when the interval was 30 mm, the temperature was close to that when only one plate was inserted. Furthermore, when the interval was 50 mm, the temperature of the plate was almost the same as that when only one plate was loaded. From this, when performing the plasma nitriding treatment under a pressure of 200 to 300 Pa or more as described above, the temperature can be easily adjusted by setting the interval between the spherical bodies to be processed to 30 mm or more. By adjusting the thickness to 50 mm or more, it is considered that the temperature can be easily adjusted. Therefore, the interval between the plurality of recesses and through holes in the spherical surface treatment jig of the present invention is preferably 30 mm or more, and more preferably 50 mm or more.

  The embodiments and examples disclosed herein are illustrative in all respects and should not be construed as being restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  A spherical surface treatment jig, a spherical surface treatment method, and a spherical component manufacturing method according to the present invention include a spherical surface treatment jig required to perform surface treatment on the entire surface, The present invention can be applied particularly advantageously to the spherical surface treatment method and the spherical part manufacturing method.

  DESCRIPTION OF SYMBOLS 1 Jig, 10 1st holding plate, 11,21 through-hole, 20 2nd holding plate, 30 clamp, 40 support member, 90 bottom wall, 91 molded object, 101,102 jig, 110 base plate, 111 protrusion part , 112 recess, 113 back surface, 121 base plate, 122 protrusion, 123 recess, 123A bottom surface, 201 jig, 210 first holding member, 211 base plate, 212 through hole, 213 guide hole, 220 second holding member, 221 Projection, 221A holding area, 222 guide bar, 223 support member, 231 support area.

Claims (9)

A first holding member having a plurality of through holes;
A second holding member having a plurality of through holes,
The plurality of through holes of the second holding member are positioned corresponding to the plurality of through holes of the first holding member by disposing the second holding member along the first holding member. A jig for surface treatment of a spherical body formed on the surface.   A fixing member that fixes a relative positional relationship between the first holding member and the second holding member in a state where the spherical body is sandwiched between the first holding member and the second holding member; The spherical surface treatment jig according to claim 1.   3. The spherical body surface treatment jig according to claim 1, wherein the plurality of through holes are arranged at an interval of at least twice the diameter of the spherical body.   The spherical surface treatment jig according to any one of claims 1 to 3, wherein the through holes are arranged at equal intervals. A spherical surface treatment method that is carried out using the spherical surface treatment jig according to any one of claims 1 to 4,
Holding the plurality of spherical bodies by the first holding member by supporting the spherical bodies one by one in each of the plurality of through holes of the first holding member;
Performing a surface treatment on the plurality of spherical bodies held by the first holding member;
Reversing the positional relationship between the first holding member and the second holding member in a state where the plurality of spherical bodies subjected to the surface treatment are sandwiched between the first holding member and the second holding member; ,
By separating the first holding member from the plurality of spherical bodies, by supporting the spherical bodies one by one in each of the plurality of through holes of the second holding member, the second holding member allows the Holding a plurality of spherical bodies;
And a step of performing a surface treatment on the plurality of spherical bodies held by the second holding member. The spherical body is made of a conductor,
The spherical surface treatment method according to claim 5, wherein the surface treatment is performed while a voltage is applied between the spherical body and a member disposed opposite to the spherical body.   The spherical surface treatment method according to claim 5, wherein the surface treatment is a plasma nitriding treatment. Preparing a spherical shaped body; and
A step of performing a surface treatment of the molded body,
The said surface treatment is a manufacturing method of a spherical component implemented using the surface treatment method of the spherical body of any one of Claims 5-7.   The method of manufacturing a spherical part according to claim 8, wherein the spherical part is a rolling element of a rolling bearing.

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