Patents Assigned to Hillman Newby Ltd.
  • Hydraulic seal with pressure-actuated ridges
    Patent number: 4557488
    Abstract: An elastomeric seal (1), particularly for mining roof supports, has a circumferentially extending primary sealing ridge (4) for sealing against the cylinder wall (15) at both low and high pressure differentials. In order to provide lubrication of the primary sealing ridge, a series of fluid reservoirs (10) are defined adjacent to opposite sides of the primary sealing ridge by a respective web (5) of secondary sealing ridges, each web consisting of a circumferential ridge (6) and a series of axial ridges (7).
    Type: Grant
    Filed: February 15, 1985
    Date of Patent: December 10, 1985
    Assignee: Hillman Newby Ltd.
    Inventor: James A. F. Litherland