The present invention provides a holding mechanism capable of well preventing misalignment of a workpiece even if the outer diameter of the workpiece is changed when the workpiece is supported at three points by a flat face and a V-shaped groove. Additionally, the present invention provides a holding mechanism of a transfer device capable of stably detecting a chucking error of holding claws for a workpiece.

A stretch rolling method and a stretch rolling unit can roll out any gripping ends and uses the narrowest possible installation space. In the stretch rolling method, a workpiece is successively fed to at least two passes of a stretch rolling unit of a gripping device, wherein the vvorkpiece is rotated by 180 about an axis of rotation lying perpendicular to the main direction of extent of the workpiece between the first pass of the two passes and the second pass of the two passes.

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.

A workpiece manipulator (1) for use with a radial forging press includes workpiece tongs (4). The workpiece tongs (4) are fastened to a manipulator frame (2) guided linearly on a manipulator track. The workpiece tongs (4) form a chuck with a fixed clamping axis (5) which extends in the forging axis or parallel to the forging axis. The workpiece can be manipulated with a linear translational movement. The manipulator frame (2) is rail-bound on wheels (12) during the translational movement.

A workpiece manipulator (1) for use with a radial forging press includes workpiece tongs (4). The workpiece tongs (4) are fastened to a manipulator frame (2) guided linearly on a manipulator track. The workpiece tongs (4) form a chuck with a fixed clamping axis (5) which extends in the forging axis or parallel to the forging axis. The workpiece can be manipulated with a linear translational movement. The manipulator frame (2) is rail-bound on wheels (12) during the translational movement.

A forging roll device includes, a pair of roll axes which are provided so that an axis center of each of the roll axes are parallel to each other and in which a die is attached to each of the roll axes; and a material holder/conveyer which conveys a held shaping target material between the pair of roll axes, wherein, each one of the pair of roll axes includes a plurality of die attaching surfaces positioned in a circumferential direction, and an outer circumferential surface between any of two of the plurality of die attaching surfaces in each one of the pair of roll axes is closer to a planar surface than a cylindrical surface with the axis center as the center.

A forging roll device includes, a pair of roll axes which are provided so that an axis center of each of the roll axes are parallel to each other and in which a die is attached to each of the roll axes; and a material holder/conveyer which conveys a held shaping target material between the pair of roll axes, wherein, each one of the pair of roll axes includes a plurality of die attaching surfaces positioned in a circumferential direction, and an outer circumferential surface between any of two of the plurality of die attaching surfaces in each one of the pair of roll axes is closer to a planar surface than a cylindrical surface with the axis center as the center.

A support apparatus for supporting a steering rack forged in a forging die, comprising a gripper to grip the shank of the rack, a lost-motion mechanism supporting the gripper and permitting limited movement in the direction of closing of the forging die, and a side-shift mechanism to move the gripper sideways. The lost-motion mechanism abuts the die assembly as the forging die closes thereby positioning the gripper to grip the shank of the steering rack during the final closing travel of the forging die. The gripper then lifts the steering rack as the forging die opens. The side-shift mechanism then moves the gripped steering rack sideways.

A support apparatus for supporting a steering rack forged in a forging die, comprising a gripper to grip the shank of the rack, a lost-motion mechanism supporting the gripper and permitting limited movement in the direction of closing of the forging die, and a side-shift mechanism to move the gripper sideways. The lost-motion mechanism abuts the die assembly as the forging die closes thereby positioning the gripper to grip the shank of the steering rack during the final closing travel of the forging die. The gripper then lifts the steering rack as the forging die opens. The side-shift mechanism then moves the gripped steering rack sideways.

A workpiece conveyance device is used for a pressing device. The workpiece conveyance device includes a support member supporting a holding component usable to detachable hold a workpiece, a lever unit including a first lever portion and a second lever portion, a lever unit support body supporting the lever unit, a first lever support portion provided to the lever unit support body, and a second lever support portion provided to the lever unit support body. The second lever portion is provided between the first lever portion and the support member. The second lever portion is rotatably linked to the first lever portion. The lever unit pivotably supports the support member. The first lever support portion pivotably supports the first lever portion. The second lever support portion slidably and pivotably supports the second lever portion.