Patents by Inventor William W. Calkins

William W. Calkins 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).

  • Pet house
    Patent number: 4021975
    Abstract: A pet house connected to the interior of a residence by a tunnel containing a vapor impervious barrier. The major portion of the pet house is located outside of the residence and contains a litter box together with ventilation means. The pet house may be opened from the outside of the residence for cleaning.
    Type: Grant
    Filed: April 2, 1976
    Date of Patent: May 10, 1977
    Inventor: William W. Calkins