A cycle is repeated a plurality of times, which includes a forging process for placing a material to be forged in a lower die and pressing the material to be forged in this state and then separating an upper die from the material to be forged; an elevation process for lifting the material to be forged by using an elevation device to separate the material to be forged from the lower die; a rotation process for rotating the material to be forged around its center by using a rotation device; and a lowering process for placing the material to be forged rotated by the elevation device in the lower die.

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. At this time, a part of the material of the intermediate material 23 is made to enter inside the annular concave sections 27, and undercut sections 32 are formed on the outer side in the radial direction of a compression-molded intermediate material 23b. After that, when removing both side sections in the axial direction of the intermediate material 23b from the inside of the molding concave sections 19a in the axial direction, the undercut sections 32 are drawn through or handled by stepped sections 29 existing at the end sections in the axial direction of the annular concave sections 27.

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. At this time, a part of the material of the intermediate material 23 is made to enter inside the annular concave sections 27, and undercut sections 32 are formed on the outer side in the radial direction of a compression-molded intermediate material 23b. After that, when removing both side sections in the axial direction of the intermediate material 23b from the inside of the molding concave sections 19a in the axial direction, the undercut sections 32 are drawn through or handled by stepped sections 29 existing at the end sections in the axial direction of the annular concave sections 27.

A process of compressing a slug to have tapered ends, then reforming the slug to change the configuration to a shorter length with a larger diameter across the center of the slug. The slug is then reformed and a hole pressed there through, with the pressing of the partial hole reforming the configuration to have a near perfect radius with a hole through the slug, whereby a near prefect ball is made, and the ball has a hole there through.

A forging apparatus includes an ironing mechanism and a phase alignment mechanism. The ironing mechanism includes: a punch set, which is fitted into a cylindrical portion of a pre-processing material to be formed into the outer joint member, and is radially expandable and contractible, the cylindrical portion having grooves formed in an inner peripheral surface thereof; and a die having a hole into which the cylindrical portion is press-fitted. The phase alignment mechanism is configured to align phases of the grooves in the inner peripheral surface of the pre-processing material and phases of track groove portion forming surfaces of the punch set with each other before the pre-processing material is fitted to the punch set.

To provide a method for manufacturing a rack that can reduce the manufacturing cost, the method comprises the following processes. An intermediate material 18a having a concave groove 42y in part in the radial direction of the outer circumferential surface that extends in the axial direction and is recessed inward in the radial direction is obtained. A plurality of rack teeth 10z are formed on an opposite surface to the concave groove 42y with respect to the radial direction of the outer circumferential surface of the intermediate material 18a by pressing the teeth-forming concave and convex section 28 that have a concave and convex configuration with respect to the axial direction in a state where the portions on both sides of the concave groove 42y of the outer circumferential surface of the intermediate material with respect to the circumferential direction are constrained and the inner surface of the concave groove 42y is not constrained.

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. At this time, a part of the material of the intermediate material 23 is made to enter inside the annular concave sections 27, and undercut sections 32 are formed on the outer side in the radial direction of a compression-molded intermediate material 23b. After that, when removing both side sections in the axial direction of the intermediate material 23b from the inside of the molding concave sections 19a in the axial direction, the undercut sections 32 are drawn through or handled by stepped sections 29 existing at the end sections in the axial direction of the annular concave sections 27.

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. At this time, a part of the material of the intermediate material 23 is made to enter inside the annular concave sections 27, and undercut sections 32 are formed on the outer side in the radial direction of a compression-molded intermediate material 23b. After that, when removing both side sections in the axial direction of the intermediate material 23b from the inside of the molding concave sections 19a in the axial direction, the undercut sections 32 are drawn through or handled by stepped sections 29 existing at the end sections in the axial direction of the annular concave sections 27.

A stock lifter for metal forming dies includes a self-contained assembly. The assembly includes a guide pin that reciprocates within a base. A hardened end cap, which contacts the stock, is attached to the guide pin. A spring is located on the exterior surface of a portion of the base and surrounds the guide pin body. One end of the spring contacts a surface on the cap, while the other end of the spring contacts a surface on the base or an optional mounting flange that is attached above the base. Thus, the stock lifter assembly has a hardened cap for the stock to slide on and a larger, externally mounted spring that provides longer life for the stock lifter. The stock lifter assembly can be made of several different lengths and sizes by using longer or wider guide pins and springs.

A stock lifter for metal forming dies includes a self-contained assembly. The assembly includes a guide pin that reciprocates within a base. A hardened end cap, which contacts the stock, is attached to the guide pin. A spring is located on the exterior surface of a portion of the base and surrounds the guide pin body. One end of the spring contacts a surface on the cap, while the other end of the spring contacts a surface on the base or an optional mounting flange that is attached above the base. Thus, the stock lifter assembly has a hardened cap for the stock to slide on and a larger, externally mounted spring that provides longer life for the stock lifter. The stock lifter assembly can be made of several different lengths and sizes by using longer or wider guide pins and springs.