Brushless DC planetary electric gearmotor
Portescap

Conventional DC motors use a stationary magnet with a rotating armature combining the commutation segments and brushes to provide automatic commutation. In comparison, the brushless DC motor is a reversed design: the permanent magnet is rotating whereas the windings are part of the stator and can be energized without requiring a commutator-and-brush system. Therefore this motor type achieves very long, trouble-free life even while operating at very high speeds.

Key Attributes:

- Frame sizes range from 12.7 mm (0.5 in.) to 58 mm (2.3 in.)
- Speeds up to 100 000 rpm
- Torque range of 3.3 mNm (0.32 oz. in.) to 316 mNm (44.7 oz. in.)
- Speed, direction, current control option are available
- Autoclavable features available
- Versions without hall sensor
- Versions with hall effect sensors

Characteristics:

- Essentially Linear torque/speed curve, with torque proportional to current and speed proportional to voltage
- No mechanical commutation via brushes
- Improved heat dissipation
- No detent torque
- Tipically used in application with variations of speed or load
- Typically used in incremental motion

Advantages:

- Ease of speed and position control
- Very long life, high reliability, insensitive to environment (no arcing), motor is dust free with reduced audible and electrical noise levels
- Overload capability
- Excellent velocity smoothness
- Very simple commutation circuitry
- Very precise speed and position control