Electric power steering apparatus and manufacturing method of pinion and/or gear for the same
AssigneeJtekt Corporation
InventorTakumi OTSUKI
Life of this patent
Estimating the term…
Abstract
An electric power steering apparatus comprises an electric motor 2 assisting a steering torque of a driver, a pinion 3 attached to the electric motor 2 and a gear 4 engaging with the pinion 3. The gear 4 has a metal part 41 and a synthetic-resin part 42 which are piled up. Teeth 42a of the synthetic-resin part 42 are wider than teeth 41a of the metal part 41 in direction of width of the teeth of the gear 4.
Claims4
An electric power steering apparatus comprising an electric motor assisting a steering torque of a driver, a pinion attached to the electric motor and a gear engaging with the pinion:
- wherein at least one of the pinion and the gear has a metal part and a flexible part which are piled up in direction of width of tooth flanks of the pinion and/or the gear, and
- wherein teeth of the flexible part are wider than teeth of the metal part in direction of width of the teeth of the pinion and/or the gear.
A manufacturing method of a gear and/or pinion, comprising steps of:
- providing a metal part blank and a synthetic-resin part blank;
- providing an intermediate blank by piling up the metal part blank and the synthetic-resin part blank;
- providing a gear blank by cutting a circumferential surface of the intermediate blank so that the gear blank has teeth of a metal part and a synthetic-resin part;
- and
- performing hygroscopic treatment to the gear blank so that the teeth of the synthetic-resin part overhang from the teeth of the metal part.
Dependencies are inferred from the claim text.