Dual Linear Guide Design

[karaszkiki]

Why is this design allows the moment load to be resolved into forces on the bearing blocks? I imagine that the bearings are considered as ideal supports whiches don't prevent rotation. Am I right or there is something else? I just want to understand, why all the catalogues say this.

 

[3DDave]

If the bearing blocks significantly resist moment then any misalignment among them or the rods will cause very high loads even before any external load is applied. Even with some flexibility there is a need for precise alignment to prevent that loading from occurring. If they were expected to carry moment loads, that load would depend on the stiffness of the plate they are attached to - which is beyond the ability of the makers to guess.

 

[karaszkiki]

Thanks for the quick response. So we basically neglect the deflection of the plate, because it probably has much higher stiffness than what could cause problems.