Abstract: Construction is achieved that, together with preventing the occurrence of damage to a mandrel, is able to improve precision of the shape of a ring-shaped member after processing. A mandrel includes a pair of support shaft sections that are provided so as to be separated in the axial direction and so as to be concentric with each other, and a rolling shaft section that is concentrically provided in the axial direction between the pair of support shaft sections. One of the support shaft sections is provided in a state in which displacement in the axial direction with respect to the rolling shaft section is regulated. The other support shaft section is provided in a state in which displacement in a direction going away from the rolling shaft section is possible when a pressing force is applied in that direction.

Abstract: With respect to the manufacture of cylindrical rolling bodies, excess material on an outside section in the radial direction and recesses in both end surfaces in the axial direction are not generated as much as possible in the intermediate material that is removed from a molding device for performing compression molding. Annular concave sections 27 are provided on the inner-circumferential surfaces 20a of molding concave sections 19a provided in a stationary-side mold 17a and a movable-side mold 18a. The stationary-side mold 17a and the movable-side mold 18a are brought close to each other in the axial direction while compressing the intermediate material 23 in a state in which both side sections in the axial direction of the intermediate material 23 are inserted into the molding concave sections 19a.

Abstract: With respect to the manufacture of cylindrical rolling bodies, excess material on an outside section in the radial direction and recesses in both end surfaces in the axial direction are not generated as much as possible in the intermediate material that is removed from a molding device for performing compression molding. Annular concave sections 27 are provided on the inner-circumferential surfaces 20a of molding concave sections 19a provided in a stationary-side mold 17a and a movable-side mold 18a. The stationary-side mold 17a and the movable-side mold 18a are brought close to each other in the axial direction while compressing the intermediate material 23 in a state in which both side sections in the axial direction of the intermediate material 23 are inserted into the molding concave sections 19a.

Abstract: A method for manufacturing an annular member includes: a cylindrical member forming step of forming a cylindrical member with an annular shape from a round bar material; and a cutting and separating step of cutting and separating the cylindrical member over an axial direction of the cylindrical member while rotating the cylindrical member, the cylindrical member being cut and separated by a shear force obtained by restraining molds, which apply an urging force to an outer circumferential surface of the cylindrical member, and by a restraining mold, which is provided with a gap on the outer circumferential surface of the cylindrical member, among a plurality of restraining molds provided on an inner circumferential surface side and an outer circumferential surface side of the cylindrical member along the axial direction, to obtain a plurality of annular members.

Abstract: A method and a system for producing a ring-shaped member. A punching process is carried out on an axial intermediate part of a first intermediate annular material so as to produce a pair of ring-shaped members. A punching step includes a step in which a first punching process is carried out over a first range of the axial intermediate part in the circumferential direction, and a step in which a second punching process is carried out over a second range of the axially-oriented intermediate part, which is at least partially different than the first range, in the circumferential direction. The first punching process is carried out such that at least one tab is formed. The second punching process is carried out such that at least one separate tab is formed, thereby producing the pair of ring-shaped members.

Abstract: There is provided a method for manufacturing ring-shaped members at a good yield and high production efficiency. To achieve this object, the following is performed. A single (a sequence of) forging produces a joined body formed by radially coupling four cylindrical portions with different inner diameter sizes. A cylindrical member that has the largest inner diameter size and a cylindrical member that has the third largest inner diameter size after the forging are employed as ring-shaped members without change. A rolling process is performed on respective cylindrical member that has the smallest inner diameter size and cylindrical member that has the second largest inner diameter size to obtain ring-shaped members. Thus, two sets of ring-shaped members are obtained as two sets of inner rings and outer rings.

Abstract: A rolling bearing includes an inner ring, an outer ring, a plurality of balls, and a cage. An annular groove for creep suppression is formed in a fitting surface of the outer ring to be fitted with a mating member (housing) to which the outer ring is to be mounted. An outer ring track groove with which the balls make rolling contact is formed in the inner peripheral surface of the outer ring on the side opposite to the fitting surface. The entire contact ellipse generated when each of the balls and the outer ring track groove contact each other is positioned within the axial range of the outer ring in which the annular groove is formed.

Abstract: A method and a system for producing a ring-shaped member. A punching process is carried out on an axial intermediate part of a first intermediate annular material so as to produce a pair of ring-shaped members. A punching step includes a step in which a first punching process is carried out over a first range of the axial intermediate part in the circumferential direction, and a step in which a second punching process is carried out over a second range of the axially-oriented intermediate part, which is at least partially different than the first range, in the circumferential direction. The first punching process is carried out such that at least one tab is formed. The second punching process is carried out such that at least one separate tab is formed, thereby producing the pair of ring-shaped members.

Abstract: A rolling bearing includes an inner ring, an outer ring, a plurality of balls, and a cage. An annular groove for creep suppression is formed in a fitting surface of the outer ring to be fitted with a mating member (housing) to which the outer ring is to be mounted. An outer ring track groove with which the balls make rolling contact is formed in the inner peripheral surface of the outer ring on the side opposite to the fitting surface. The entire contact ellipse generated when each of the balls and the outer ring track groove contact each other is positioned within the axial range of the outer ring in which the annular groove is formed.

Abstract: Construction is achieved that, together with preventing the occurrence of damage to a mandrel, is able to improve precision of the shape of a ring-shaped member after processing. A mandrel includes a pair of support shaft sections that are provided so as to be separated in the axial direction and so as to be concentric with each other, and a rolling shaft section that is concentrically provided in the axial direction between the pair of support shaft sections. One of the support shaft sections is provided in a state in which displacement in the axial direction with respect to the rolling shaft section is regulated. The other support shaft section is provided in a state in which displacement in a direction going away from the rolling shaft section is possible when a pressing force is applied in that direction.

Abstract: There is provided a method for manufacturing ring-shaped members at a good yield and high production efficiency. To achieve this object, the following is performed. A single (a sequence of) forging produces a joined body formed by radially coupling four cylindrical portions with different inner diameter sizes. A cylindrical member that has the largest inner diameter size and a cylindrical member that has the third largest inner diameter size after the forging are employed as ring-shaped members without change. A rolling process is performed on respective cylindrical member that has the smallest inner diameter size and cylindrical member that has the second largest inner diameter size to obtain ring-shaped members. Thus, two sets of ring-shaped members are obtained as two sets of inner rings and outer rings.

Abstract: A rolling bearing includes an outer ring, an inner ring, a plurality of balls disposed between the outer ring and the inner ring and allowed to roll, and a snap cage that is made of resin and holds the balls. The snap cage includes an annular main portion and a plurality of cage bars. The cage bars each protrude from a right side surface of the main portion. Pockets are formed between the cage bars to house the respective balls. An inner circumferential surface and an outer circumferential surface of each of the cage bars in a radial direction have respective tilted surfaces that form a tapered shape in an axial direction. This allows lubricant oil to flow well in the rolling bearing in both directions.

Abstract: A rolling processing device and a rolling processing method are provided to be capable of producing annular members by rolling-forming three or more cylindrical members at the same time while reducing the possibility of breakage of a mandrel. For this purpose, a rolling processing device includes a forming roll, a support roll, and a mandrel. Plural workpieces are arranged on the mandrel alternately in the radial direction of the mandrel. The rolling processing method includes an arranging process for arranging the workpieces on the mandrel and a rolling process.

Abstract: A rolling bearing includes a resin cage. The resin cage includes a pair of split members split in two halves in an axial direction. Each of the split members has pocket portions and coupling portions alternately arranged in a circumferential direction. On a first coupling portion of the coupling portions coupled together, an engagement pawl is formed which protrudes from a coupling surface in the axial direction. On a second coupling portion, an engagement groove is formed which is recessed in the axial direction with respect to the coupling surface and into which the engagement pawl is inserted. The engagement pawl has a base portion and a pawl portion engaging with the second coupling portion. An insertion hole is formed in the first coupling portion so as to pass through the first coupling portion in the axial direction such that a mold is inserted into the insertion hole.

Abstract: A rolling bearing includes an outer ring, an inner ring, a plurality of balls disposed between the outer ring and the inner ring and allowed to roll, and a snap cage that is made of resin and holds the balls. The snap cage includes an annular main portion and a plurality of cage bars. The cage bars each protrude from a right side surface of the main portion. Pockets are formed between the cage bars to house the respective balls. An inner circumferential surface and an outer circumferential surface of each of the cage bars in a radial direction have respective tilted surfaces that form a tapered shape in an axial direction. This allows lubricant oil to flow well in the rolling bearing in both directions.

Abstract: A method for manufacturing an annular member includes: a cylindrical member forming step of forming a cylindrical member with an annular shape from a round bar material; and a cutting and separating step of cutting and separating the cylindrical member over an axial direction of the cylindrical member while rotating the cylindrical member, the cylindrical member being cut and separated by a shear force obtained by restraining molds, which apply an urging force to an outer circumferential surface of the cylindrical member, and by a restraining mold, which is provided with a gap on the outer circumferential surface of the cylindrical member, among a plurality of restraining molds provided on an inner circumferential surface side and an outer circumferential surface side of the cylindrical member along the axial direction, to obtain a plurality of annular members.

Abstract: A rolling bearing includes a resin cage. The resin cage includes a pair of split members split in two halves in an axial direction. Each of the split members has pocket portions and coupling portions alternately arranged in a circumferential direction. On a first coupling portion of the coupling portions coupled together, an engagement pawl is formed which protrudes from a coupling surface in the axial direction. On a second coupling portion, an engagement groove is formed which is recessed in the axial direction with respect to the coupling surface and into which the engagement pawl is inserted. The engagement pawl has a base portion and a pawl portion engaging with the second coupling portion. An insertion hole is formed in the first coupling portion so as to pass through the first coupling portion in the axial direction such that a mold is inserted into the insertion hole.

Abstract: A raceway member (6) of a wheel support hub unit, having wheel or vehicle body fixing portions (7) extending radially outward from a solid or hollow shaft portion, and a wheel or vehicle body positioning cylindrical portion (9) extending concentrically with the shaft portion, the fixing portion (7) being formed by the cold side extrusion so that the fixing portion is integral with the shaft portion (5).

Abstract: This invention provided a manufacturing method to process a small-diameter step section 18 on an inside end section of a hub body 13a that comprises an outward facing flange 15 and a positioning cylinder 16 stably and with high precision. In this invention, an intermediate material 40 is pressed between a lower punch 36 and an upper punch 46 with an outer peripheral surface of the intermediate material 40 being held by a lower die 37 and an upper die 43, and then a part of the intermediate material 40 is pressed into the lower punch 36 such that the small-diameter step section 18 is formed by cold plastic working.

Abstract: A raceway member (6) of a wheel support hub unit, having wheel or vehicle body fixing portions (7) extending radially outward from a solid or hollow shaft portion, and a wheel or vehicle body positioning cylindrical portion (9) extending concentrically with the shaft portion, the fixing portion (7) being formed by the cold side extrusion so that the fixing portion is integral with the shaft portion (5).