Patents by Inventor Lawrence Kreyer

Lawrence Kreyer 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: 4158224
    Abstract: A method and an apparatus consisting of at least one inverter for converting a d.c. supply voltage to an alternating voltage for application across a load. More specifically, an inverter is disclosed consisting of two power darlington transistors having their collectors connected to an input of a load, a power supply having upper and lower supply voltage outputs connected to the emitters of the two transistors, and unique drive circuitry for alternately biasing each of the transistors on and off through control of their respective base terminals with voltages equal to or referenced to the upper and lower supply voltage outputs. The drive circuitry does not utilize transformers and incorporates circuitry which prevents simultaneous conduction of the two transistors.
    Type: Grant
    Filed: November 21, 1977
    Date of Patent: June 12, 1979
    Assignee: Unilog Systems Corporation
    Inventors: Lawrence Kreyer, Thomas G. Matherly