Patent ID: 6672055
Filing Date: 2004-01-06
Classification: E02F,F04B

Abstract:
A hydraulic-pump controller which is equipped in a hydraulic system, in which hydraulic pumps are driven by an engine so that operating oil is supplied to hydraulic actuators manipulated by manipulation means, and which also controls regulators of said hydraulic pumps so that absorbed torque of said hydraulic pumps balances with an output of said engine, said hydraulic-pump controller comprising:engine speed detection means for detecting engine speed of said engine; discharge pressure detection means for detecting discharge pressure of said hydraulic pumps; manipulation-amount detection means for detecting an amount that said manipulation means is manipulated, or a physical quantity correlating with said amount; discharge flow rate predicting means for predicting discharge flow rates of the operating oil which are discharged from said hydraulic pumps according to manipulation of said manipulation means, based on an output of said discharge pressure detection means and an output of said manipulation-amount detection means; predictive engine speed computing means for calculating the absorbed torque of said hydraulic pumps, based on said discharge flow rates predicted by said discharge flow rate predicting means and an output of said discharge pressure detection means, and then computing a predictive engine speed of said engine from the calculated absorbed torque of said hydraulic pumps; and regulator control means for controlling said regulators, based on a deviation between said predictive engine speed computed by said predictive engine speed computing means and an actual engine speed detected by said engine speed detection means.