Patents by Inventor Walter H. Liff

Walter H. Liff 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).

  • Bird watering apparatus
    Patent number: 4640226
    Abstract: A watering container for birds having spaced inner and outer walls integrally molded from plastic with electrical heating elements contacting the inner wall controlled so that energy is provided to the heating elements is progressively increased with the fall of ambient temperature below freezing.
    Type: Grant
    Filed: October 23, 1985
    Date of Patent: February 3, 1987
    Inventor: Walter H. Liff
  • Animal watering apparatus
    Patent number: 4561384
    Abstract: A watering container for domestic animals having spaced inner and outer walls integrally molded from plastic with electrical heating elements contacting the inner wall controlled so that energy provided to the heating elements is progressively increased with the fall of ambient temperature below freezing.
    Type: Grant
    Filed: October 18, 1984
    Date of Patent: December 31, 1985
    Inventor: Walter H. Liff