The Japanese precision motor manufacturer Nippon Pulse has collaborated with the German encoder-maker Siko to produce what they claim is the first linear motor to incorporate a non-analogue magnetic linear encoder. The scale-less SL083 motor is aimed at positioning applications that need the repeatability, reliability and robustness of a linear motor, with a resolution and repeat accuracy of up to 5μm.
The compact motor consists of two parts: a tubular stainless-steel shaft, and a non-contact forcer. This results in simple installation and configuration. The efficient motor needs no lubrication, and its non-critical 0.5mm air gap means there is no variation in force as the gap varies during the stroke or if the shaft is turned in the forcer. The housing is made of non-magnetic aluminium.
The motor is said to be easy to integrate into applications, because it can use existing bearings to create an actuator. The true encoder allows the motor to provide a smooth sinusoidal motion profile. The linear encoder scale is integrated into the shaft.
Nippon Pulse's tubular linear motor has a built-in magnetic encoder
As well as the encoder, the motor has a built-in interpolator and Hall sensors. It offers real-time signal processing and high dynamics with no residual force. The motor can achieve a maximum speed of 4m/s, can deliver an acceleration force of 11.5N and a continuous force of 2.9N, and is claimed to offer a good force-to-volume ratio.
