Mounting frame: solidity and stability – BECKHOFF AL2000 Application User Manual
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Mounting frame: solidity and stability
The propelling forces of a linear motor are relatively high. Therefore the frame needs sufficient dynamic stiff-
ness. Because of the required accuracy the frame should be insensible to shocks and vibrations.
A linear motor system gaines its accuracy by means of a high bandwidth feedback control loop. In this loop all
mechanical parts such as load, frame and mountings are involved as well as the characteristics of the servo-
controller and the linear encoder. The loop can be compromised by the characteristics of the construction. A
bad construction can even cause total loss of control of the linear motor system.
Attention should be paid to the machine’s natural frequencies. Especially vibrations between 50 - 500 Hz in
driving direction can be harmful for accuracy. To meet main problems a rule of thumb is: the motorsystem
should be rigidly connected to a massive and rigid body of at least 3 times the mass of the accelerated load.