The brushed linear servo motor is designed for long stroke servo applications. It is ideal for direct linear motion without mechanical linkages in closed-loop position packages.
The moving permanent magnet brush commutated DC linear motor consists of a stationary primary and a moving secondary. The stationary primary is a steel laminated core, with multiple coils inserted into insulated slots. The ends of each coil are connected to a commutator bar that is mounted on an aluminum angle.
The moving secondary features multiple permanent magnets and brushes for commutation. A cable supplies power to the moving secondary. Mounting holes are located on both the primary and secondary.
The magnetic-attractive force between the primary and secondary can be used as a magnetic preload for the bearing system. The customer-supplied bearing system must maintain an air gap of 0.064 cm [0.025 inch] between the primary and secondary. The brush linear motor is available in different cross sections to meet different force requirements.
- High forces to 1070 N [171 Lbs.]
- High acceleration to 49 m/s/s [5g’s]
- High speeds to 3.8 m/s [75 in/sec]
- High accuracy 8.3 µm/m [±0.0001 in/ft] (encoder dependent)
- High repeatability 1 µm [0.00004 in] (encoder dependent)
- Stroke lengths to 3.2m [11 ft.]
- Multiple moving magnet assemblies with overlapping trajectories
- Self-commutation enables the use of low-cost brush-type amplifiers.
- Relatively low cost per pound of thrust compared to brushless linear motors
- Use with PWM brush-type servo control (refer to Baldor’s DC Controls – LD Series)