Patents by Inventor Bernard Hoffmann

Bernard Hoffmann 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: 5723933
    Abstract: An electronically commutated DC machine, especially a DC motor, comprises a permanent magnet rotor providing a cylindrical air gap having a homogeneous magnetic field with straight, radially extending field lines and continuously alternating polarity. An iron-free stator means is formed like a self-supporting stator coil made of conductor material and cured synthetic resin comprises straight coil portions extending within the air gap. In order to provide machine, especially a motor, adapted for air cooling and providing a high current density, high-dynamic features and good overload capacity and further providing a behaviour essentially linear to the supplied current, the conductor material of each coil portion is consisting of one or several strand(s), wherein each strand comprises a number of thin filaments, being individually insulated, being arranged twisted within the strand and having a diameter equal or less than 0.4 mm.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: March 3, 1998
    Assignee: Orto Holding A.G.
    Inventors: Andreas Grundl, Bernard Hoffmann, Reiner Rasch