A method for setting conditions for a shaft diameter enlargement, a shaft diameter enlargement method, and a shaft diameter enlargement apparatus are provided. A controller of the shaft diameter enlargement apparatus controls a compressing section, a bending section, and a rotating section to enlarge an intermediate portion of a shaft workpiece to have a predetermined outer diameter by rotating the shaft workpiece about its axis with axial compressive force a bending angle being applied to the intermediate portion. The controller determines whether the shaft workpiece is acceptable, based on the number of rotations of die shaft workpiece required for enlarging the intermediate portion to have the predetermined outer diameter or based on an enlargement ratio of the intermediate portion.

A method for setting conditions for a shaft diameter enlargement, a shaft diameter enlargement method, and a shaft diameter enlargement apparatus are provided. A controller of the shaft diameter enlargement apparatus controls a compressing section, a bending section, and a rotating section to enlarge an intermediate portion of a shaft workpiece to have a predetermined outer diameter by rotating the shaft workpiece about its axis with axial compressive force a bending angle being applied to the intermediate portion. The controller determines whether the shaft workpiece is acceptable, based on the number of rotations of die shaft workpiece required for enlarging the intermediate portion to have the predetermined outer diameter or based on an enlargement ratio of the intermediate portion.

To provide a method of manufacturing a shaft for a steering device, the shaft including a spline shaft part to be coupled with an input shaft, a stopper part to be coupled with an output shaft, and an intermediate shaft part that couples the spline shaft part with the stopper part. The method includes: a step of forming a hole part recessed in an axial direction from one end of a pillar-shaped material by forging; and a step of pressing the material in which the hole part has been formed into a die to perform drawing in a radial direction on a portion of the material at which the spline shaft part and the intermediate shaft part are formed, and prolonging a length along the axial direction of the hole part at the same time by forging.

To provide a method of manufacturing a shaft for a steering device, the shaft including a spline shaft part to be coupled with an input shaft, a stopper part to be coupled with an output shaft, and an intermediate shaft part that couples the spline shaft part with the stopper part. The method includes: a step of forming a hole part recessed in an axial direction from one end of a pillar-shaped material by forging; and a step of pressing the material in which the hole part has been formed into a die to perform drawing in a radial direction on a portion of the material at which the spline shaft part and the intermediate shaft part are formed, and prolonging a length along the axial direction of the hole part at the same time by forging.

A shaft assembly comprises a hollow shaft and at least one working component disposed therein. A method of forming the shaft assembly includes a step of providing at least one generally planar preform. The preform is then formed into a “U”-shaped partial cylinder. One or more working components may then be assembled and connected to an interior of the partial cylinder. The partial cylinder is then further formed into a hollow cylinder having a generally circular cross-sectional shape, thus surrounding the one or more working components to secure a position thereof in an interior of the hollow cylinder. The hollow cylinder may then be held stationary and a welding operation performed thereon to form the hollow shaft. Once the hollow shaft is welded, post process machining may then be performed thereon as desired to further finish the hollow shaft.

There is provided a method of manufacturing a variable wall thickness steel pipe with a hollow tubular raw pipe. The method of manufacturing a variable wall thickness steel pipe includes locking the raw pipe in a die by thrusting a plug into the raw pipe from an one end side, so as to expand an outer shape on the one end side in a state, where the raw pipe is disposed inside the die and movement of the raw pipe in a longitudinal direction is restricted; and performing ironing in which an inner shape of the raw pipe is expanded while the outer shape is maintained so that a thin portion is formed by further thrusting the plug toward the other end side of the raw pipe while the locked state of the raw pipe is maintained, whereas the restriction on the raw pipe is relaxed.

This torsion beam manufacturing method is for manufacturing a torsion beam including a central portion of which a cross-section orthogonal to a longitudinal direction is a closed cross-section having a substantial V-shape or a substantial U-shape at any position in the longitudinal direction, and a shape changing portion which has a connection region leading to the central portion and including a closed cross-section having a shape different from the shape of the closed cross-section of the central portion. This torsion beam manufacturing method has a compression step of thickening at least the connection region through application of a compression force in the longitudinal direction to at least the connection region of a torsion beam material to obtain the torsion beam, the torsion beam material being formed with the central portion and the shape changing portion.

A method for producing a shaft, which is at least partially not circular in cross-section, from a substantially cylindrical blank by means of radial forging, wherein the blank is not rotated in a final radial forging process.

A method for producing a shaft, which is at least partially not circular in cross-section, from a substantially cylindrical blank by means of radial forging, wherein the blank is not rotated in a final radial forging process.

A remanufactured pinion shaft includes a salvage member secured to a replacement member. The salvage member may be formed from a damaged pinion shaft and includes first gear teeth proximate a first axial end and a first alignment member proximate a second axial end. The replacement member includes second gear teeth proximate a first axial end and a second alignment member proximate a second axial end. The first alignment member and the second alignment member cooperate to transmit rotational motion between the first salvage member and the replacement member and/or align the salvage member relative to the replacement member.