| 摘要 |
PROBLEM TO BE SOLVED: To provide a gear for a power unit capable of making a cost and durability compatible, by specifying a thickness of a hard carbon coating film on an acceleration tooth flank and a deceleration tooth flank of the gear, and a manufacturing method therefor. SOLUTION: A spattering particle constituting the hard carbon coating film 13 is deposited on the acceleration tooth flank 11 in a rotation-directional advancing side of a workpiece W more than on the deceleration tooth flank 12 in a rotation-directional delay side thereof, since a rotation direction is brought into the rotation direction same to that of the gear when accelerating the power unit assembled in with the gear, when film-forming the hard carbon coating film 13 by a PVD method, while rotating the workpiece W worked into a gear shape, and the thickness of the hard carbon coating film 13 on the acceleration tooth flank 11 is thereby thickened more than that of the deceleration tooth flank 13 on the deceleration tooth flank 12. The thickness of the deceleration tooth flank 13 on the deceleration tooth flank 12 receiving a relatively low load is thereby prevented from getting excessive, to contribute to cost reduction, while securing sufficiently the thickness of the hard carbon coating film 13 on the acceleration tooth flank 11 receiving a relatively high load, to enhance the durability. COPYRIGHT: (C)2011,JPO&INPIT |
