Patents by Inventor Kjell D. Rundkvist

Kjell D. Rundkvist 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: 4528608
    Abstract: An electronic current interrupter included in a DC distribution system contains a transistorized power circuit (EK), a threshold circuit (JF), a time circuit (TK) and holding circuit (HK). In one embodiment, the power circuit comprises a power transistor (T1) connected in series with the load and with a resistor (R1) in the threshold circuit. There is a current-limiting path containing a transistor (T2) and a current-limiting resistor (R4) in parallel with a power transistor (T1). When the load current exceeds a given value, the threshold circuit sends a voltage blocking the power transistor (T1) simultaneously as the transistor (T2) in the current-limiting path becomes conductive. After a given time (t), determined by the time circuit (TK), the holding circuit sends a voltage which also blocks the transistor (t2) in the current-limiting path, and the power circuit (EK) becomes entirely non-conductive to the load current.
    Type: Grant
    Filed: October 13, 1983
    Date of Patent: July 9, 1985
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventors: Hans O. V. Andersson, Kjell D. Rundkvist, Per E. Samsioe