Patents by Inventor Robert D. Pierson

Robert D. Pierson 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: 4274088
    Abstract: A portable alarm particularly useful for protecting works of art in art galleries and museums is a self-contained alarm system in a display base member. The alarm is energized in response to the operation of either of two switches, in turn activated by spring biased plungers normally biased to extend out of the bottom and top surfaces, respectively, of the base member. When the base member is placed on a support such as a table, one of the switches is deactivated. When a work of art is placed on the top of the base member, the other switch plunger is depressed and its associated switch is deactivated. The alarm then is enabled for operation by a key operated switch connected in series circuit with the alarm and a silicon controlled rectifier (SCR).
    Type: Grant
    Filed: May 27, 1980
    Date of Patent: June 16, 1981
    Inventors: Don H. Pierson, Robert D. Pierson