Patents by Inventor William P. Schafer

William P. Schafer 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: 4621945
    Abstract: In association with a subsurface drainage/irrigation tile system, a head control stand is provided to selectively control the flow of water through a drainage/irrigation tile system and in turn control the depth of the water table. An actuating unit which includes a water level sensor floating on the surface of the water table is disposed within a riser pipe which extends upward from a subsurface drainage tile. A valve disposed within the drainage tile is connected to the water level sensor and opens upon the sensor raising in response to a raising in the water table which allows water to flow through the valve and subsequently closes the valve upon lowering of the water table.
    Type: Grant
    Filed: January 11, 1985
    Date of Patent: November 11, 1986
    Inventors: Christopher E. Schafer, William P. Schafer, Charles J. Schafer