Patents by Inventor Rex Mountford Davis

Rex Mountford Davis 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: 6081080
    Abstract: A method and apparatus for reducing winding failures in electric machines resulting from the application of high frequency or high dV/dt voltage pulses or voltage signals to the phase windings of the machine in which an inductive element is provided between the source of the high-frequency or high dV/dt pulses and the phase winding to absorb a portion of the voltage stresses on the phase windings that result from the application of the high-frequency or high dV/dt pulses to the machine.
    Type: Grant
    Filed: November 20, 1997
    Date of Patent: June 27, 2000
    Assignee: Switched Reluctance Drives, Ltd.
    Inventor: Rex Mountford Davis
  • Patent number: 5949170
    Abstract: A method and apparatus for reducing winding failures in reluctance machines wherein winding coils for the switched reluctance motor are formed and positioned such that the turn-to-ground capacitance of the portion of the winding coil coupled to an electronic motor controller is reduced. Alternate embodiments are disclosed wherein additional insulation, and capacitive voltage distributors are provided to enable a switched reluctance motor to better handle the voltage stresses produced when high frequency or high dV/dt voltage pulses are provided to the motor.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 7, 1999
    Assignee: Switched Reluctance Drives, Ltd
    Inventor: Rex Mountford Davis
  • Patent number: 5703457
    Abstract: A polyphase switched reluctance machine has only n power cable connections for n phases. Each phase winding includes a series connected diode and the phase windings and their diodes are arranged in a conducting ring. Alternating currents are fed to the nodes of the conducting ring from an inverter. The nodal connections between the phases allows the alternating current to energize the windings where previously only a greater number of cables and a unidirectional current would have been required. Due to the presence of alternating current, a transformer may be interposed between the inverter and the nodes of the conducting ring to allow a boosted voltage to be delivered over long distances.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: December 30, 1997
    Assignee: Switched Reluctance Drives, Ltd.
    Inventor: Rex Mountford Davis
  • Patent number: 3931530
    Abstract: In apparatus for controlling the supply of power from an alternating current electrical supply of at least three phases to a resistive load, the load is so arranged that there exist current paths both between each phase connection of the load and two adjacent phase connections of the load and between each phase connection of the load and a common point which is directly connected to the neutral of the supply. The switching means for connecting each phase of the load to the corresponding phase of the supply is arranged to change from a non-conducting to a conducting state only when the voltage across such switching means is substantially zero, and to change from a conducting to a non-conducting state only when the current through each switching means is substantially zero.
    Type: Grant
    Filed: July 19, 1974
    Date of Patent: January 6, 1976
    Assignee: National Research Development Corporation
    Inventors: Rex Mountford Davis, Brian Robert Downing