US 6,659,219 B2 · Electric power steering device

Abstract

An easy-to-assemble electric power steering device, in which an approximately cylindrical housing is divided at about the central part into a first chamber and a second chamber. The first chamber is for housing a motor for assisting the steering force. A stator of the motor is inserted at one end of the housing and fixed. The second chamber is for housing a rack shaft assembly which comprises a rack shaft connected with the steering shaft and a ball screw mechanism. The rack shaft assembly is inserted at the other end of the housing, to thereby spline a rotor of the motor for assisting the steering force with a nut of the ball screw mechanism. A bearing supporting the nut of the ball screw mechanism is axially movably held in the inner wall of the second chamber. The rack shaft is arranged through the first and second chambers of the housing.

Claims6

Dependent claims

An electric power steering device, comprising:

a rack shaft connected with a steering shaft;
a motor for assisting a steering force with a rotor coaxially disposed on said rack shaft;
a ball screw mechanism, in which balls are interposed between a nut splined with said rotor and a screw formed on said rack shaft;
and
a single integrally formed housing formed approximately cylindrical on the whole and divided at about the central part into a first chamber and a second chamber and open at opposing ends thereof;
wherein, said first chamber of said housing and said motor for assisting the steering force are cooperatively adapted for said motor to be inserted at one of said open ends and installed;
said second chamber of said housing and said ball screw mechanism are cooperatively adapted for said ball screw mechanism to be inserted at the other open end, and installed;
and said rack shaft is inserted through said first and second chambers of said housing and disposed.

5 more elements

Dependencies are inferred from the claim text.

Electric power steering device

Life of this patent

Electric power steering device

Life of this patent

Abstract

Claims6