Patents by Inventor Donald Hugh Dowling

Donald Hugh Dowling 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).

  • Radio-controlled machine power cut-off
    Patent number: 4057805
    Abstract: A pair of battery-powered radio transmitters are individually worn on the wrists of a machine operator, and two radio receivers are tuned to receive the signals broadcast by the radio transmitters, the first radio receiver being a proximity-sensitive device switching off the driving power to the machine whenever either radio transmitter comes within a preselected safe distance limit from the work-accomplishing region of the machine whereas the second radio receiver is a radio transmitter operating state-verifying device switching off the driving power to the machine whenever either or both of the radio transmitters fails to transmit its characteristic broadcast signal.
    Type: Grant
    Filed: March 30, 1976
    Date of Patent: November 8, 1977
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Donald Hugh Dowling