Steering Shaft Stopper Geometry for Stress-Reduced Rotation Limits

The patent transitions from a conventional perpendicular abutment configuration to an inclined abutment configuration. The first abutting surface is inclined relative to the radial direction, and the first abutted surface is inclined relative to the axial direction, effectively changing the dimensional orientation of the abutment interaction. This dimensional change allows the abutment surfaces to be larger without increasing the circumferential width, thereby reducing stress concentration while maintaining the rotation range.

The patent changes the geometric parameters of the abutment surfaces by introducing inclination angles. The first abutting surface is inclined at an angle α relative to the radial direction, and the first abutted surface is inclined at an angle β relative to the axial direction. This parameter change transforms the abutment from a point or line contact to a surface contact with distributed area, reducing stress concentration without requiring increased circumferential width.

The patent merges the rotation restriction function into the existing rotary member structure. The first abutting surface is formed on the rotary member itself, and the first abutted surface is formed on the housing, integrating the stopper functionality with the rotary member rather than adding separate stopper components. This merging approach restricts rotation range while maintaining structural simplicity.

The rotary member serves multiple functions: it transmits rotation from the steering shaft, supports the steering angle sensor, and incorporates the abutting surface for rotation range restriction. The housing simultaneously serves as the support structure for the rotary member and provides the abutted surface for rotation restriction. This multi-functionality reduces the need for additional dedicated restriction components.