Beckhoff Releases New Linear Motors to Help Industrial Motor Control Techniques
Learn about the new AL8000 range of linear motors and how can it help with future industrial motor control and design techniques.
Advancement of Linear Motors
Linear motors are electromechanical devices that can be considered a standard motor unrolled into a straight line. Instead of having a circular encasing whose stator can only rotate, a linear motor consists of a line of alternating permanent magnets, creating a track whose stator consists of coils around the permanent magnets.
Instead of rotary motion, a linear motor allows the stator to move along the track of magnets, creating linear motion.
One challenge engineers face when using linear motors is their ability to provide a high degree of force compared to other linear systems such as threaded rods. While adding more coil elements to a linear motor servo can increase the force, the size and number of coils are generally up to the manufacturer. This can add more in parallel is rarely an ideal solution.
Beckhoff’s AL8000 Series
Beckhoff recently announced the AL8000 series of linear motors. These motors are modular, meaning that customers can choose from a few different servo sizes and combine them as required. This allows for custom servo designs with varying force capabilities, acceleration, and power consumption.
Beckhoff's new AL8000 series of linear motors. Image used courtesy of Beckhoff
The AL8000 series also utilizes a common design standard with threaded holes separated by 40mm. This enables systems designers and control engineers to combine multiple servos by not taking precise measurements of each servo being used. It also allows multiple servo combinations to be used in the same machine carriage without any modifications.
Depending on the force of the linear motors, users can choose between water cooling and air cooling. If water cooling is required, two ports on either facet of the motor allow for pipes to be fitted or connections made to additional servos. The forces that the new servo range can exert depends on the motor size, with the smallest providing up to 120N and the largest providing 6750N. The maximum speed of the AL8000 series is 12m/s.
The size specifications of these new motors. Image used courtesy of Beckhoff
The widths of the motors range from W2 (50mm) to W6 (130mm). Tracks are constructed using magnetic plates whose widths also vary from W2 to W6, and these tracks can be used to create a linear motor of any length.
Future Industrial Designs
Linear motors using magnetic tracks can provide engineers with a whole range of benefits. These benefits include no backlash, high accelerations, and immediate force from the main carriage. However, the Beckhoff AL8000 range offers engineers a new concept not typically found in other linear motor systems, flexibility.
Industrial applications require motion systems with a high degree of accuracy, repeatability, and responsiveness, which can all be provided by linear motors. But creating linear motor systems using pre-defined servo sizes can limit designs.
The use of the AL8000 may help engineers create a servo to their own specifications. But the ability to customize the length of a servo is not the unique advantage; designs can be easier to maintain and repair. If a servo should fail in a design a maintenance team merely needs to identify which servo has failed, remove the other servos attached, and then replace the faulty part.
A video showing how these motors work. Video used courtesy of Beckhoff
The use of a standard 40mm separation that the replacement will fit correctly and any change in the size of that replacement will still see all other servo modules correctly connect to their carriage.
Beckhoff’s latest linear motor was designed to address some of these common challenges.