Patents by Inventor David E. Johnston

David E. Johnston has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4519616
    Abstract: A shaft seal consists of a one-piece rigid plastics moulded ring with a thick holding portion and a thin sealing head having a flexing leg and a sealing bush to make an interference fit and fine running clearance seal against an opposed cylindrical surface.
    Type: Grant
    Filed: October 21, 1983
    Date of Patent: May 28, 1985
    Assignee: George Angus & Company Limited
    Inventor: David E. Johnston
  • Patent number: 4462600
    Abstract: A rotary fluid seal having a flexible sealing ring which floats between relatively rotatable counterface members and has contact faces which bear on the counterfaces under the influence of centrifugal force, such as forms the subject of U.S. Pat. No. 4,348,031, is provided with a rigid spring-retaining ring which permits but limits centrifugal expansion of a spring loading the contact faces against the counterfaces.
    Type: Grant
    Filed: January 12, 1984
    Date of Patent: July 31, 1984
    Assignee: George Angus & Company Limited
    Inventor: David E. Johnston
  • Patent number: 4348031
    Abstract: A rotary fluid seal, especially an oil seal for a rotary shaft, comprises a sealing ring between axially-opposed divergent frusto-conical counterfaces of relatively rotatable members, preferably casing rings in a self-contained seal unit, the sealing ring having a pair of divergent sealing lips presenting frusto-conical contact faces to the counterfaces and being substantially coaxial with but floating freely between the relatively rotatable members, the contact faces bearing frictionally on the counterfaces so that, on relative rotation of the members, the sealing ring is frictionally driven into rotation by one or other of the members and the effect of centrifugal force, tending to cause the sealing lips to flex angularly outwardly, reduces the bearing load of the contact faces on the counterfaces.
    Type: Grant
    Filed: March 9, 1981
    Date of Patent: September 7, 1982
    Assignee: George Angus & Company Limited
    Inventor: David E. Johnston
  • Patent number: 4348030
    Abstract: A face seal, such as for a water pump in the cooling system of an internal combustion engine, comprises a rigid sealing ring carried by the free end of a moulded elastomeric sleeve on a mounting cup, the sleeve having at about its mid-length a circumferential flexible junction, defined by a surrounding groove with a contractile spring seated therein, and the sleeve being geometrically equivalent to an axially opposed pair of frusto-conical parts forming a toggle system which, under the pressure of sealed fluid, exerts a balancing axial bearing load on the sealing ring.
    Type: Grant
    Filed: May 6, 1981
    Date of Patent: September 7, 1982
    Assignee: George Angus & Company Limited
    Inventor: David E. Johnston