Electronically commutated DC machine

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. Said conductor material and liquid resin have been compacted in order to provide a stator coil comprising a content of conductor material of from 70 to 90% by volume.

Dependencies are inferred from the claim text.