Patents by Inventor Owen H. Libby

Owen H. Libby 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: 5067519
    Abstract: An improved safety valve includes piston-actuated provisions for gradually pressurizing a fluid-actuated motor during start-up of the system, preferably by way of a changeable flow restriction. In addition such improved safety valve preferably includes a floating exhaust valve actuating apparatus movable in an exhaust closure chamber and that operates in response to the presence or absence of line pressure in the exhaust closure chamber for respectively blocking off or opening fluid communication between the safety valve's outlet port and exhaust port. A pilot operator is also included for selectively permitting or cutting off line pressure flow to actuate the piston actuator and the exhaust valve actuating apparatus. The preferred safety valve also includes a check valve for preventing back-flow from the safety valve's outlet port back to the piston actuator and back to the exhaust valve actuating apparatus.
    Type: Grant
    Filed: November 26, 1990
    Date of Patent: November 26, 1991
    Assignee: Ross Operating Valve Company
    Inventors: Neil E. Russell, Owen H. Libby