Patent ID: 7305821
Filing Date: 2007-12-11
Classification: F15B,F16H

Abstract:
1. A hydraulic control apparatus, comprising: a variable capacity pump; a first change over valve group including at least one change over valve connected with a first delivery line branched from a delivery line of the variable capacity pump and arranged to have a load sensing function; a delivery flow control means for adjusting a delivery flow rate of the variable capacity pump by receiving a hydraulic oil pressure signal from a load sensing line arranged in accordance with the change over valve having the load sensing function; a second change over valve group including at least one change over valve connected with a second delivery line branched from the delivery line of the variable capacity pump; an open and close motion valve connected with the second delivery line at a upstream side of the second change over valve group and having functions of open and close, and throttle in accordance with a hydraulic operation pressure signal applied to the change over valve belonging to the second change over valve group; and a compensation valve arranged at a downstream side of the open and close motion valve; an outlet side of the compensation valve being connected with the second change over valve group,