ELECTRIC POWER STEERING DEVICE

摘要

PROBLEM TO BE SOLVED: To further enhance the steering feeling of an electric power steering device while achieving cost reduction and weight saving.SOLUTION: An electric power steering device 10 includes: a column shaft 22: a pinion shaft 26 interlocked to the column shaft via a universal joint 23; a rack shaft 28 interlocked to the pinion shaft via a rack-and-pinion mechanism 27; and an auxiliary torque mechanism 60 adding an auxiliary torque to a steering torque generated in a steering wheel 21. The auxiliary torque mechanism includes a torque sensor 61 detecting the steering torque, an electric motor 63 generating the auxiliary torque on the basis of the steering torque, and an auxiliary torque transmission mechanism 64 transmitting the auxiliary torque to either one of the rack and pinion shafts. The only one universal joint is a nonconstant velocity universal coupling. The torque sensor is disposed at a steering column 41 for supporting the column shaft.SELECTED DRAWING: Figure 1