Patent · US Expired

Control system for helical screw compressor

US4147475A · kind A · utility

17Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 6, 1977
Grant dateApr 3, 1979
Priority date
Expiry dateSep 6, 1997

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04C28/24
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A helical screw air compressor unit has a rotary capacity control valve, a compressor inlet throttling valve, and a pressure relief valve for venting the compressor discharge conduit. A control circuit senses pressure in the compressed air supply system downstream of the compressor and operates the capacity control valve, inlet throttling valve, and pressure relief valve in a predetermined sequence to provide an improved power consumption characteristic for variable demand compressor applications. The control circuit includes a hydraulic control valve and an actuator for operating the rotary capacity control valve to regulate compressor throughput to maintain a predetermined pressure without overpressuring the supply system during operation at conditions of reduced demand for compressed air.

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