Patents by Inventor Rennie L. Dickson

Rennie L. Dickson 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: 4624315
    Abstract: A surface controlled subsurface well safety valve for use in a well tubing string including a flapper valve member, an operator tube for opening the flapper valve member and holding it open, an annular piston on the operator tube operative in response to control fluid pressure conducted from the surface, a spring biasing the operator tube to a position at which the flapper valve is closed, and a temporary lockout sleeve mounted in tandem with the flapper valve operator tube for movement simultaneously with the operator tube to a position at which the operator tube is inoperative and the temporary sleeve holds the flapper valve open, the operator tube and flapper valve having means for engagement of a lockout tool to operate the operator tube and lockout sleeve simultaneously. The lockout sleeve can be returned to inoperative position by control fluid pressure return of the operator tube to a position in which the tube holds the flapper valve open.
    Type: Grant
    Filed: October 5, 1984
    Date of Patent: November 25, 1986
    Assignee: Otis Engineering Corporation
    Inventors: Rennie L. Dickson, Roddie R. Smith