Patent ID: 6164320
Filing Date: 2000-12-26
Classification: F15B,F16F,Y10T

Abstract:
A damper valve for a hydraulic power steering device which is disposed in a hydraulic oil circuit connecting an oil passage changing-over valve in a gear box and left and right oil chambers of a power cylinder,the damper valve comprising a piston valve which is arranged and constructed to be opened by through-flow of hydraulic oil returned back to the oil passage changing-over valve from either one of the left and right chambers of the power cylinder, anda spring which closes the piston valve, anda check valve which is disposed in a valve body of the piston valve and which is arranged and constructed to allow only hydraulic oil supplied from the oil passage changing-over valve to either one of the left and right chambers of the power cylinder to flow through the check valve,wherein the piston valve opens against biasing force of the spring, and is arranged and constructed such that a throttle oil passage is formed by through-flow of the returned hydraulic oil having a predetermined oil pressure or less and a fully opened oil passage is formed by through-flow of the returned-back hydraulic oil having more than the predetermined oil pressure, anda passage of the returned-back hydraulic oil disposing around diametrical direction of the check valve disposed portion, inside of the valve body of the piston valve and the spring is housed in the passage of the returned-back hydraulic oil.