Operating system for a valve

摘要

A control system is provided for a hydraulic actuating system having a multi-phase stepping motor with a driver therefor which supplies and controls DC current through each of the motor windings such that no current is induced into the control winding from adjacent windings. The stepping motor precisely controls the rotation of an eccentric cam engaging an actuating plunger which actuates a control valve of the hydraulic actuating system. The driver receives control signals from a computer programmed to calculate, from user input command signals indicative of the desired system condition, and generate those control signals which most quickly achieve a rough approximation of the desired system condition. After this rough approximation is attained, the computer generates new control signals for the driver as a function of feedback signals and/or system component characteristics so as to precisely achieve the desired system condition. The operating system for the valve includes a bearing arrangement rotatably connected about the eccentric cam. This cam engages the actuating plunger through a connection linkage which includes the bearing arrangement and a linkage for maintaining contact between the plunger and an outer race of the bearing arrangement. Different embodiments of this operating system are disclosed showing means of applying different loading torques and valve response times.