Gear skiving process method

A gear skiving process method in which a tooth-cutting process is performed on a surface to be cut, which is either an external peripheral surface or an internal peripheral surface of a cylindrical workpiece, the gear skiving method comprising the steps of:

• positioning a first skiving cutter at a first processing position in a circumferential direction on the surface to be cut of the workpiece such that a predetermined depth of cut is achieved;
• positioning a second skiving cutter at a second processing position set apart by 180° in the circumferential direction from the first processing position on the surface to be cut such that a predetermined depth of cut is achieved;
• disposing the first skiving cutter so as to be at a first axis crossing angle in relation to the workpiece, and disposing the second skiving cutter so as to be at a second axis crossing angle in relation to the workpiece;
• and
• performing a tooth-cutting process on the surface to be cut by one or both of the first and second skiving cutters, in which the first and second skiving cutters are fed simultaneously in a direction along a rotation axis of the workpiece while the workpiece and the first and second skiving cutters are caused to rotate synchronously,
• wherein
• the first skiving cutter and the second skiving cutter have opposite helix angles;
• the first axis crossing angle and the second axis crossing angle are inclined in relation to the workpiece rotation axis by a same amount in opposite directions;
• the tooth-cutting process performed on the surface to be cut includes a first step and a second step;
• in the first step, the first and second skiving cutters are simultaneously fed in a direction along a workpiece center axis while the workpiece and the first and second skiving cutters are caused to rotate synchronously about respective axes thereof in a first direction, parts that are to be one set of tooth flanks among left tooth flanks and right tooth flanks of teeth to be created in the surface to be cut are cut by the first skiving cutter, and the second skiving cutter is not involved in cutting the surface to be cut;
• and
• in the second step, the first and second skiving cutters are simultaneously fed in the direction along the workpiece center axis while the workpiece and the first and second skiving cutters are caused to rotate synchronously about the respective axes thereof in a second direction opposite to the first direction, parts that are to be the other set of tooth flanks among the left tooth flanks and the right tooth flanks of the teeth to be created in the surface to be cut are cut by the second skiving cutter, and the first skiving cutter is not involved in cutting the surface to be cut.