Patent ID: 6173802
Filing Date: 2001-01-16
Classification: B62D

Abstract:
An electric power steering device, comprising:a yoke made of a tubular member, and carrying magnetic field generating means on an inner circumferential surface thereof;a hollow motor shaft coaxially and rotatably received in said yoke, and carrying a motor armature which cooperates with said magnetic field generating means to form an electric motor for the power steering device;a drive shaft coaxially and axially slidably received in said hollow motor shaft, and provided with a threaded section; anda threaded nut mechanism including a nut member which is coaxially and fixedly secured in said hollow motor shaft and threadably engages with said threaded section of said drive shaft so as to convert a rotational movement of said motor shaft into an axial movement of said drive shaft, wherein a section of said yoke extending from a part thereof surrounding an axial end of said motor shaft adjacent to said threaded nut mechanism to an adjacent axial end of said yoke defines an inner diameter such that said inner diameter of said section is greater than an outer diameter of said nut member over the entire length of said section.