Patent · US Expired

Power transmission

US4757747A · kind A · utility

19Cited by
4References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 1986
Grant dateJul 19, 1988
Priority date
Expiry dateAug 29, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/42237
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

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

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.