Torque detecting device and electric power steering system
AssigneeJtekt Corporation
InventorNoritake Ura
Life of this patent
Estimating the term…
Abstract
A torque detecting device and an electric power steering system are provided. A torque sensor includes a first rotor that is fixed to an input shaft and that has a predetermined shaft angle multiplier, and a second rotor that is fixed to an output shaft and that has a shaft angle multiplier different from that of the first rotor. In first to fourth output coils arranged on a stator that is arranged around outer peripheries of the first and second rotors, electric signals having different phases are generated on the basis of a variation of a gap between the stator and the first and second rotors. A twist angle of a torsion bar is calculated on the basis of the electric signals, and a torque that acts between the input shaft and the output shaft is calculated on the basis of the twist angle.
Claims5
A torque detecting device that detects a torque that acts between first and second shafts respectively coupled to both ends of a torsion bar, comprising:
- a first resolver rotor that is fixed to the first shaft and that has a predetermined shaft angle multiplier;
- a second resolver rotor that is fixed to the second shaft and that has a shaft angle multiplier different from that of the first resolver rotor;
- a resolver stator that is arranged in proximity to outer peripheries of the first and second resolver rotors;
- four output coils that are arranged on the resolver stator and that respectively generate electric signals having different phases on the basis of a variation of a gap between the resolver stator and the first and second resolver rotors due to rotation of the first and second resolver rotors;
- and
- computing means for calculating a difference between rotation angles of the first and second shafts as a twist angle of the torsion bar on the basis of the electric signals that are respectively generated in the four output coils, and calculating the torque on the basis of the twist angle.
Dependencies are inferred from the claim text.