Patents by Inventor Paul Pfeffer

Paul Pfeffer 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: 4174494
    Abstract: This system for controlling the operation of several electric motors notably for blinds and similar devices comprises a plurality of decentralized control devices each associated with one motor and controlled from a central control means via a common control line. Each decentralized control device comprises, for each direction of rotation of the motor concerned, a relay and, for each motor, control means connected in parallel to the common control line. The control means for each relay comprise a switch connecting the common line to the middle point of the pair of inverters controlling the two directions of rotation of the motor. The front contact of each inverter controls the energization of the corresponding relay and the back contact of each inverter controls the self-energization of the relay of the other inverter via a self-energization contact provided on the other relay.
    Type: Grant
    Filed: November 14, 1977
    Date of Patent: November 13, 1979
    Assignee: Etablissements Carpano & Pons
    Inventor: Paul Pfeffer