Patents by Inventor Bruce D. Sandig

Bruce D. Sandig 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).

  • Double valve apparatus
    Patent number: 4820408
    Abstract: Double valve apparatus is used in a swimming pool chlorinating system for injecting chlorine gas into a swimming pool when a swimming pool pump is operating. Two valve elements move on and off two valve seats for preventing air from bleeding back to the water pump when the pump is not operating and for preventing back pressure in the system from introducing water into the chlorine gas line.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: April 11, 1989
    Assignee: Dial Manufacturing, Inc.
    Inventor: Bruce D. Sandig