Linear Drive Calculation for Standard Axis

In the following calculations, terminology & data used are taken from page 20.1) Calculate the running speed of the motor - this then allows the motor torque at this speed to be read from the manufacturer’s data.2) Calculate the total available linear force.3) Calculate the force required to accelerate the moving parts at the desired rate.4) Calculate the force required to overcome friction.Ff = Fba + Sw =Vw x Rr x 1002 P r H H Ft =Tw x d x g x Rr x 100r Fa = Aw ML+Mc +2LMb+ Fa = Aw ML+L(Mb+Mbs) + Mp +Ip+Rr

{ ( )} { )}(

2Ip+Rr
2 (Im+Ig)r
2 M x La5) Calculate the force required to do work (example equation is for the unit moving a mass M
L plus the carriage up a slope of angle Q to the horizontal).Fw = (ML + Mc ) x g x sin Q 6) Calculate the motor torque safety factor. If this is greater than 1 the DLS should perform the required duty, but it is recommended to have a higher value of Sf than this to provide a margin of safety. Sf =FtFa + Ff + Fw

Linear Drive Calculation for Cantilever Axis

The calculations for use with the cantilever axis are similar in approach to that for standard axes, but to allow for the system differences, equation 3 must be changed as follows:3) Calculate the force required to accelerate the moving parts at the desired rate:Depending on the application, the calculation of the force required to do work (equation 5) may also need to change, for instance if the cantilever axis is required to move a mass ML plus the carriage up a slope of angle
2 (Im+Ig)r
2 Q to the horizontal, it is the weight of the beam, slide, mounting plate and load which move, while the carriage and drive are stationary. The modified version of equation 5 is as follows:Fw = (L x (Mbs + Mb) +Mp + ML) x g x sin Q With these modifications, the calculations will yield the true result.
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