Patents by Inventor Ekkehard Lefeldt

Ekkehard Lefeldt 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: 5530365
    Abstract: A process used to locate cable faults, in particular to locate non-burnout cable faults in the vicinity of branched cables. The pulse reflection method is used and a capacitor is charged and then discharged across a spark gap by means of spark-over at a fault in the cable. Simultaneously with a main capacitor in an impulse wave generator, a second pulse capacitor is discharged into the cable by means of a short circuit switch. The resulting reflection wave is input via a decoupler into a first channel of a digital storage unit. After opening the short circuit switch, the main capacitor in the impulse wave generator and the second pulse capacitor are again charged and then again discharged into the faulty cable by closing the main switch. The pulse capacitor is discharged by means of a plasma-triggered spark gap. The spark gap is triggered by the charge of the impulse wave generator.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: June 25, 1996
    Assignee: Hagenuk GmbH
    Inventor: Ekkehard Lefeldt
  • Patent number: 4866392
    Abstract: A testing apparatus for testing with D.C. and charging a cable. Through periodically switchable switching elements, like a switch-over or a switching rotor, the cable alternately swings via a choke coil and rectifier into an opposite polarity and re-swings again during the ensuing reswitching via a choke coil and rectifier into the previous polarity. As a result, the cable, after each switching break, is charged up to the original voltage by a testing apparatus with positive or negative polarity in order to compensate for the swing-over and current losses.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: September 12, 1989
    Assignee: HDW-Elektronik GmbH
    Inventor: Ekkehard Lefeldt
  • Patent number: 4825171
    Abstract: A testing apparatus for testing with D.C. and charging a cable. Through periodically switchable switching elements, like a switch-over or a switching rotor, the cable alternately swings via a choke coil and rectifier into an opposite polarity and re-swings again during the ensuing reswitching via a choke coil and rectifier into the previous polarity. As a result, the cable, after each switching break, is charged up to the original voltage by a testing apparatus with positive or negative polarity in order to compensate for the swing-over and current losses.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: April 25, 1989
    Assignee: HDW-Elektronik GmbH
    Inventor: Ekkehard Lefeldt