| 摘要 |
<p>A commutator motor such as a series motor or a permanent magnet motor to be incorporated in portable machine tools, preferably hand machine tools such as drills, said motor comprising a stator (2) with a winding or a permanent magnet arranged in the machine housing (1) and a rotor (3) with a commutator journalled therein, the electric connection between commutator and current supply being ensured by a pair of diametrically opposite brushes (10) having different polarities, said brushes being displaceable with respect to the commutator axis for varying the filed angle between stator and rotor. Further the suspension or fastening of the brushes in the electric motor is arranged in a manner such that the introduction of the brushes into the holder is facilitated, the electric contact between brush and holder is improved, the shape of the brush itself remains simple and/or the pressing force of the brush on the commutator ring can remain substantially constant even after some amount of wear and, respectively, can exhibit an increasing or decreasing pressure characteristic curve.</p> |
