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