Koyo Seiko Company, Ltd.

Fumiyoshi Ono

Noboru Minamoto

Masanori Kobayashi

Takashi Ohata

Yoshiyuki Saito

A portion of an oil path between an actuator for generating steering assistance power and a pump is formed by the inside space S in a housing covering an input shaft. A bearing assembly supporting the input shaft in the inside space has a bearing joined to one of the outer and inner circumferences of a circular spacer, and is inserted between the outer circumference of the input shaft and the inner circumference of the housing via radial clearances. The displacement of the bearing assembly toward one axial direction can be restrained by the contact between the contact portion formed on the other of the circumferences of the spacer and the receiving portion formed on either the housing or the input shaft, and the bearing assembly is pressed toward one axial direction by the oil pressure in the inside space.

Hydraulic power steering device

A hydraulic pressure control valve includes a cylindrical valve body and a valve spool coaxially fitted therein, each having oil grooves and lands alternately provided on and along the respective peripheral inside and outside surfaces, the opposing oil grooves and lands having throttles therebetween whose throttling extent, are changeable in accordance with a relative angular displacement between the valve body and the valve spool such that the flow of a working oil is concentrated in wider throttles. Thus noise due to cavitation is reduced.

Growing community of inventors

Shiki-gun, Japan

Fumiyoshi Ono