Now part of the range of products for machine builders from Techdrives, a division of Lenze Ltd, are electric actuators that run from small/light duty through to high power. Linear actuators are offered with DC, AC and servo motors. Screw jacks in two ranges suit heavier applications and standard motor input flanges allow the same connection. With linear actuators and screw jacks overlapping in forces, speeds and strokes, a well-matched selection is possible for a broad range of requirements.
Techdrives offers the LinearMech brand of actuators, which are small-to-medium in performance and easy to specify, plus the Servomech brand of actuators and screw jacks suiting heavier tasks. The combined range suits forces from 100N to 350kN. A typical 'light' application is load lifting on an industrial washing machine using a 24V DC actuator capable of 1000N and strokes up to 300mm. Sometimes high speed is required, for example on parcel diverters. A typical specification might be 3000N at 265mm/s using a 1.1kW motor. At the 'heavy' end of the spectrum, screw jacks drive lifting platforms with a load of 100kN and a speed of 12.5mm/s, strokes up to 1.8m.
Linear actuators and screw jacks compete with pneumatics, which can cost less, and hydraulics, which can achieve very high forces. However, the electric option offers particular advantages. Connections are very much easier, with no need for expensive pipework. Leakage is not a problem – which is a particular advantage in food production. When the electric actuator or screw jack is turned off there is no energy usage, whereas pneumatic and hydraulic lines must remain pressurised. Perhaps the biggest advantage for the electric option is the controllability, with simple options to measure and position movement, even down to a fraction of a millimetre.
The Techdrives website brings together all the necessary information on linear motion products including summaries, catalogue downloads, enquiry and data sheets. Acme threads for simple application and ball screws for higher efficiency and heavier duties are offered. Screw jack options include travelling nut and travelling screw versions. The seamless range allows the designer a precise match for load speeds, forces and strokes.