Patents by Inventor Ralph Prete

Ralph Prete 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: 5546295
    Abstract: Due to the intermittent nature of electrical connection through moving contacts on electrically propelled vehicles, electrical power converters such as power supplies and inverters are subject to large voltage transients. For compactness and low weight, a high-frequency power converter comprised series-connected high-speed switching circuits, so that an input voltage with voltage transients is split between the switching circuits. As a result, lower-rated switching elements such as IGBT's and MOSFET's can be used while maintaining resistance to input-voltage transients.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: August 13, 1996
    Assignee: Rotron Incorporated
    Inventors: Ralph Prete, Vladimir Brunstein, Todd J. Kazmirski
  • Patent number: 4500949
    Abstract: A chopping type electrical converter having a primary circuit utilizing controlled rectifiers for chopping the input voltage, a secondary circuit for providing a DC output voltage, and a control unit which continuously monitors current flow in the secondary circuit and delays trigger pulses to the controlled rectifiers in the primary circuit whenever it is unsafe or undesirable to trigger them. In a preferred embodiment, the controlled rectifiers are mounted in series-connected pairs with a step-down transformer for each controlled rectifier. The number of pairs and the interwoven triggering order of the controlled rectifiers enables high voltage and high frequency operation with minimal stress on the converter components. The control unit prevents each member of each pair of controlled rectifiers from being triggered whenever the other member of the pair is still conducting, or whenever current is flowing in the secondary winding of the transformer associated with the controlled rectifier.
    Type: Grant
    Filed: February 14, 1983
    Date of Patent: February 19, 1985
    Assignee: Stone Safety Corporation
    Inventor: Ralph Prete