Electrohydraulic system with distributed control.

摘要

An electrohydraulic system includes a plurality of electrohydraulic devices (22a-22n) individually controlled by on-board microprocessor-based control electronics (56, 58, 60). Each individual device controller (26) is connected to and addressable by a master controller (36) for coordinating operation of the various devices. An electrohydraulic servo valve assembly (34) includes a hydraulic manifold (42) having a valve spool (44) variably positionable therein under control of a torque motor (49). A microprocessor-based controller (56, 58, 60) is connected to the torque motor (49) and is mounted on the manifold (42) by a cover (40) which encloses and protects both the controller (26) and the torque motor (36). A watchdog timer (110) in the microprocessor-based controller (56, 58, 60) monitors pulsewidth modulated signals to the torque motor (49) for terminating operation in the event of signal loss. In a preferred embodiment of the invention, the servo valve assembly (34) is coupled to a linear actuator (24) which has its position monitored by an electroacoustic transducer (80). Improved electronics (56, 92) couple the transducer (80) to the control microprocessor (100).