Patents by Inventor Philip N. Douglas

Philip N. Douglas 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: 4112343
    Abstract: The disclosed system includes a direct-current bridge circuit and a bridge-balancing reversible motor coupled to the bridge circuit, together with a differential high-gain amplifier which is responsive to even slight bridge unbalance to polarize the motor for rotation in the direction toward rebalance of the bridge circuit and also interrupts the motor operation when balance of the bridge is passed in either direction. Apparatus is included responsive to both positive and negative reversals in the polarity of unbalance of the bridge for deenergizing the motor when the null of the bridge is crossed in either direction.
    Type: Grant
    Filed: April 27, 1977
    Date of Patent: September 5, 1978
    Assignee: Cornell-Dubilier Electric Corp.
    Inventor: Philip N. Douglas