Festo Actuators Offer +/-10 Micron Repeatability

Festo has brought out an extensive range of ultra-compact precision electric actuators that can be ordered from its online shop. This means that machine designers and builders can now take delivery of positioning actuators offering +/-10 micron repeatability within 24 hours of placing their order. Downloadable PC-based software for dimensioning electromechanical linear axes and electric motors, backed by native CAD models of the actuators, helps users accelerate design-in and machine build. Festo's new EGSK and EGSP series actuators provide exceptionally accurate positioning capabilities.

Featuring a one-piece solid-steel housing that also serves as a guide rail - conveying a high degree of rigidity to the design - they are ideal for applications demanding short and precise moves, especially where space is limited. Their low profile makes them particularly suitable for the type of small pick-and-place systems and X-Y tables used in the semiconductor manufacturing and pharmaceutical industries. The EGSK and EGSP electric actuators offer a choice of three classes of precision, with repetition accuracies of +/-3, +/-5 or +/-10 microns.

They are available in two performance categories, to help maximise applications flexibility. The EGSK range of standard-performance electric actuators comprises five models, with profile heights from 15 - 46mm. All five models employ a ball-screw drive, with a choice of pitches, and offer a wide variety of stroke lengths - from 25 to 800mm, depending upon the particular model. The +/-10 micron precision class versions of all EGSK actuators, which are suitable for the majority of applications and are therefore likely to prove the most popular, are available off-the-shelf from Festo.

The EGSP range of high-performance electric actuators use caged re-circulating ball bearings between the carriage and the guide, to further reduce friction and noise. There are four models in the range - with profile heights of 20, 26, 33 and 46mm - and again, each model is available with a choice of ball-screw drive pitches and a variety of stroke lengths, ranging from 25 to 800mm. The two largest-size actuators also employ caged ball-bearing chains in the ball-screw drive assembly, to ensure smooth, trouble-free operation under heavy load conditions.

All Festo EGSK and EGSP electric actuators feature four rows of ball bearings circulating within the loaded area of the moving carriage to maximise rigidity and help ensure a long service life. The ball bearings run between the honed grooves of the carriage and the linear guide until they are returned by means of the reversers in the end plates and the recirculation channels. The four rows of balls are arranged at a contact angle of 45 degrees, which means the guide carriage has the same basic load ratings in both radial coordinate directions; the actuator can therefore be used in any mounting position and can accommodate a wide range of load conditions.

EGSK and EGSP electric actuators are fully compatible with Festo's range of stepper and servo motors and controllers, and can also be used with third-party motors. Festo produces a comprehensive range of motor mounting flanges and couplings, as well as actuator-mounting plates and axial mounting kits. The company also offers optional cover kits for these actuators, plus a sensor rail kit that enables inductive position sensors to be attached to the left or right side of the actuator body. Festo has also developed a powerful PC-based software tool to help machine designers and other potential users make the best use of electric-drive technology such as the EGSK actuators.

This positioning drive software enables users to choose the optimum components for a complete, high-efficiency positioning system, and can be downloaded free of charge from the electric-drive technology page at Festo's website. Once a few application details have been entered, the software automatically calculates the ideal combination of electric linear axes, motors, gear units, controllers and software, from a widely coordinated product range. By specifying various project parameters, users can also obtain the load-characteristic values for the selected drive, quickly and reliably.