Patents by Inventor Robert Lawler

Robert Lawler 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).

  • Graded resistance solid state current control circuit
    Patent number: 8614868
    Abstract: A circuit fault detector and interrupter which consists of parallel current conduction paths, including a path through a mechanical contactor and a path through a power electronics switch having active feedback control. A fault can be detected by a fault detection circuit within 50 ?S of the occurrence of the fault, causing the mechanical contactor to be opened and the fault current to be commutated via a laminated, low-inductance bus through the power electronics switch. The power electronics switch is thereafter turned off as soon as possible, interrupting the fault current and absorbing the inductive energy in the circuit. The fault current can be interrupted within 200 microseconds of the occurrence of the fault, and the device reduces or eliminates arcing when the mechanical contactor is opened.
    Type: Grant
    Filed: June 7, 2012
    Date of Patent: December 24, 2013
    Assignee: SPD Electrical Systems, Inc.
    Inventors: Robert Lawler, John P. Barber, John I. Ykema
  • GRADED RESISTANCE SOLID STATE CURRENT CONTROL CIRCUIT
    Publication number: 20120243137
    Abstract: A circuit fault detector and interrupter which consists of parallel current conduction paths, including a path through a mechanical contactor and a path through a power electronics switch having active feedback control. A fault can be detected by a fault detection circuit within 50 ?S of the occurrence of the fault, causing the mechanical contactor to be opened and the fault current to be commutated via a laminated, low-inductance bus through the power electronics switch. The power electronics switch is thereafter turned off as soon as possible, interrupting the fault current and absorbing the inductive energy in the circuit. The fault current can be interrupted within 200 microseconds of the occurrence of the fault, and the device reduces or eliminates arcing when the mechanical contactor is opened.
    Type: Application
    Filed: June 7, 2012
    Publication date: September 27, 2012
    Applicant: SPD ELECTRICAL SYSTEMS
    Inventors: Robert Lawler, John P. Barber, John I. Ykema