Patents Assigned to Thomas Willett & Company Limited
  • Pumping system
    Patent number: 4184331
    Abstract: A pumping system for pumping liquid clay or slip into a filter press comprises a hydraulically-powered double-acting ram for pumping the slip and a hydraulic control circuit for the ram. The control circuit includes a pair of hydraulic pumps one of which provides a high pressure, low volume delivery and the other of which provides a low pressure high volume delivery, and valves controlling the supply of oil from these pumps to the ram according to the resistance encountered by the ram.
    Type: Grant
    Filed: February 27, 1978
    Date of Patent: January 22, 1980
    Assignee: Thomas Willett & Company Limited
    Inventor: Peter N. Bentley