Commutation system for a DC motor

A commutation system for a DC motor having a stator including a plurality of windings and a permanent magnet assembly, the assembly comprising:

• a housing;
• at least three collector segments connected to stator windings inside the housing;
• a rotor assembly in the housing including a rotary distributor with brushes for sliding contact with the collector segments, the brushes extending from the rotor parallel to a motor axis;
• wherein the brushes are attached to the rotary distributor to rotate coaxially therewith and to contact a surface of the collector segments, wherein the contact surfaces of the brushes and the collector segments lie substantially perpendicular to the motor rotation axis;
• a tubular sliding electrode positioned in the housing to feed current to the rotary distributor and the brushes;
• and
• a spring acting against the tubular sliding electrode in a direction parallel with the motor rotation axis to ensure proper contact between the tubular sliding electrode and the rotary distributor as well as between the contact surfaces of the brushes and the collector segments.

A commutation system for a DC motor having a stator including a plurality of windings and a permanent magnet assembly, the assembly comprising:

• a housing formed of a composite material;
• at least three collector segments connected to stator windings inside the housing;
• a rotor assembly in the housing including a rotor having a distributor with brushes for connecting the collector segments, the brushes extending from the rotor parallel to a motor axis;
• wherein the brushes are attached to the rotor to rotate coaxially therewith and to contact a surface of the collector segments, wherein the contact surface between the collector segments and the brushes is conical shaped and nonparallel with respect to the motor axis;
• a spring positioned in the housing and oriented to ensure contact between the brushes and the collector segments, the spring further being oriented such that a centrifugal force due to rotation of the rotor and its distributor does not act in a parallel direction of the spring;
• and
• an electrode between the spring and the distributor, the spring conducting electrical current to the electrode.