公开(公告)号：US3698580A

公开(公告)日：1972-10-17

申请号：US3698580D

申请日：1969-12-22

Applicant: INT HARVESTER CO

Inventor： CARLSON ERNEST C ,  HOWELLS ARTHUR J JR ,  JENNINGS MARVIN D ,  EASTMAN DONALD R ,  SHEETS EDWARD G

IPC: E02F9/22 ,  E02F3/28

CPC classification number: E02F9/22 ,  Y10T74/20201

Abstract: A control system for a hydraulic motor actuated material handling mechanism including a source of fluid power, a directional flow control valve interposed between the source of fluid power and the hydraulic motor, a bridge circuit including a source of electrical energy and having a first variable impedance branch varied by a command control lever and a second variable impedance branch associated with the flow control valve, comparator means connected to the output of the bridge circuit for detecting and amplifying an unbalance in the bridge circuit and means interconnected between the comparator and the directional flow control valve for controlling said valve in a manner corresponding to command movement of the variable impedance branch.