Patents by Inventor Benigno Diaz

Benigno Diaz 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).

  • Sewer pest control check valve
    Patent number: 3955596
    Abstract: A sewer pipe valve section comprising a removable one-way check valve and a separate removable screen is provided to be interposed between the building sewer drain system and that of the city. A linkage retains the screen in a normally raised inoperative position when the one-way check valve is in a lowered operative position and permits the screen to be lowered into operative position when the check valve is raised and removed for cleaning the pipe.
    Type: Grant
    Filed: September 10, 1973
    Date of Patent: May 11, 1976
    Inventor: Benigno Diaz