Magnetic steering angle detection apparatus

• US 7,000,487 B2
• Filed: 09/11/2003
• Issued: 02/21/2006
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: Takuma, Emi
• Primary Examiner(s): NOORI, MAX H
• Application Number:
  US10/659,269
• Publication Number:
  US 20040118220A1
• Time in Patent Office: 894 Days
• Field of Search: 738/623.32, 738/623.31, 738/623.33, 738/623.35
• US Class Current: 73/862.333
• CPC Class Codes: B62D 15/02 Steering position indicators ; Steering position determination; Steering aids
• CPC Class Codes: G01D 5/145 influenced by the relative movement between the Hall device and magnetic fields see G01R33/06

Abstract

A magnetic steering angle detection apparatus includes a magnet rotating in synchronization with a steering shaft mounted on a vehicle, senses a change of a magnetic field from the magnet by use of a hall IC mounted on a column side, and detects a rotation angle of the steering shaft. The magnet has S and N poles arranged on a plane of which normal line is in a substantially axial direction of the steering shaft. The hall IC is disposed such that a sensing direction of the hall IC is set to be a substantially single direction and the sensing direction is made to substantially coincide with the axial direction of the steering shaft.

Claims

1. A magnetic steering angle detection apparatus, comprising:

magnets rotating at different speeds in synchronization with a steering shaft mounted on a vehicle; and

magnetic sensors mounted adjacent respective magnets, the magnetic sensors configured to detect a rotation angle of the steering shaft by sensing a change of a magnetic field emitted from the magnets,

wherein each magnet has S and N poles arranged on a plane of which a normal line is in a substantially axial direction of the steering shaft; and

each magnetic sensor is disposed such that a sensing direction thereof is set to be a substantially single direction coinciding with the axial direction of the steering shaft.

3. The magnetic steering angle detection apparatus according to claim 1, wherein each magnetic sensor is provided on a position where a component of the magnetic field from the magnet in the axial direction of the steering shaft is detectable.

5. The magnetic steering angle detection apparatus according to claim 1, wherein each magnetic sensor is a hall IC formed of a plurality of hall elements.

2. A magnetic steering angle detection apparatus, comprising:

a first gear rotating in synchronization with a steering shaft mounted on a vehicle;

a second gear rotating in synchronization with the first gear at a speed faster than a speed of the first gear;

a third gear rotating in synchronization with the first gear at a speed slower than a speed of the second gear;

magnets rotating in synchronization with the second and third gears, respectively;

magnetic sensors provided in vicinities of the magnets of the second and third gears, respectively, the magnetic sensors configured to sense changes of magnetic fields from the magnets of the second and third gears; and

a computation unit configured to compute a rotation angle of the steering shaft by detecting rotation angles of the second and third gears based on sensing signals from the magnetic sensors,

wherein each of the magnets provided on the second and third gears has S and N poles arranged on a plane of which normal is in a substantially axial direction of the steering shaft; and

each of the magnetic sensors is disposed such that a sensing direction thereof is set to be a substantially single direction and the sensing direction is made to substantially coincide with the axial direction of the steering shaft.

4. The magnetic steering angle detection apparatus according to claim 2, wherein the magnetic sensors are provided on positions where components of the magnetic fields from the magnets in the axial direction of the steering shaft are detectable.

6. The magnetic steering angle detection apparatus according to claim 2, wherein the magnetic sensors are hall ICs, each of which is formed of a plurality of hall elements.