Patents by Inventor Dudley R. Medhurst

Dudley R. Medhurst 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).

  • Determining the volume of gases in transformer cooling oil
    Patent number: 5243848
    Abstract: Apparatus for determining the volume of gas dissolved or entrapped in transformer cooling oil includes an oil receiver, a metering space and a piston pump arranged to apply a reduced pressure to oil in the receiver and to transfer the gas which is liberated from the oil into the metering space. The piston pump is connected to and controlled by a controller. The metering space comprises a cylinder which accommodates a piston which is connected to be moved by an actuator which is connected to and controlled by the controller. The pressure detector is provided which is responsive to the pressure in the metering space and is arranged to deliver a signal indicative of the magnitude of the pressure to the controller. A transducer is connected to the controller and is arranged to produce a signal, when the said pressure reaches a predetermined value, which is indicative of the volume of gas within the metering space.
    Type: Grant
    Filed: April 17, 1992
    Date of Patent: September 14, 1993
    Assignee: The National Grid Company PLC
    Inventors: Brian M. Cox, Dudley R. Medhurst