Patents by Inventor Peter R. Hohlfeld

Peter R. Hohlfeld 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: 5380983
    Abstract: An electrical appliance, such as a pressing iron (10), includes a user proximity sensor for removing electrical power from the appliance after a period of non-use. When a user's hand is in close proximity to, or is in a grasping relationship with, a handle (28) of the pressing iron, an antenna (44) that is disposed within the handle is capacitively coupled to the user through a dielectric material that forms the handle wall. When so coupled to the user, a displacement current having a frequency equal to the AC line electrical power frequency signal (50 Hz or 60 Hz) is capacitively coupled between the user's body and the antenna. The displacement current is detected and amplified by circuitry (60) that is connected to the antenna by a conductor (46). This circuitry outputs a signal that indicates the proximity of the user to the handle of the pressing iron. The output signal is in turn employed to disable the operation of a time-out circuit (70).
    Type: Grant
    Filed: July 12, 1993
    Date of Patent: January 10, 1995
    Assignee: Black & Decker Inc.
    Inventors: Luis O. Cavada, Joseph Carley, Leonard I. Horey, Peter R. Hohlfeld