Support for a self-propelled linear motion drive apparatus

摘要

The invention supports a mechanical carriage at three contact points for precise positioning on two guide rails, one guide rail having a V-grooved surface and the other having a flat surface. Two of the three contact points are recirculating ball bearings mounted against the V-grooved rail. The third contact point is on the flat rail and is also the driving contact point and comprises a drive shaft having a friction wheel thereon engaged with the flat rail to drive the mechanical carriage. The recirculating ball bearings and friction wheel are loaded against the V-grooved and flat rails, respectively, by magnets mounted on the carriage and spaced from the rails by an air gap. The air gap provides for a magnetic force between the magnets and the guide rails while permitting relative movement therebetween.