Patents by Inventor Johannes Anton Greefkes

Johannes Anton Greefkes 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).

  • Switching system for an automatic telecommunication exchange with a plurality of intermediate lines that are grounded when not in use
    Patent number: 4097693
    Abstract: Switching system for an automatic telecommunication exchange with space- and time division multiplex. A two-stage switching network is described which, from the traffic-technical point of view is the equivalent of a single switching matrix. The switching network is divided into two stages in such a way that the crosstalk is reduced. The two stages are interconnected via time division multiplex intermediate lines. The intermediate lines which are not used for connection at any moment are grounded. Controlling the crosspoints does not require more routing memories as for a single switching matrix having the same number of inputs and outputs.
    Type: Grant
    Filed: June 9, 1976
    Date of Patent: June 27, 1978
    Assignee: U.S. Philips Corporation
    Inventor: Johannes Anton Greefkes