High-force linear motor assembly using tandem axes

A rapid-positioning drilling assembly substitutable for existing drilling assemblies, comprising:

• (a) at last one pair of movable, oppositely-faced tied frames, each frame presenting at least two pairs of opposed parallel bearing surfaces, the center lines connecting said surfaces of each pair being at an angle with respect to the other for a frame;
• (b) a pair of parallel rails for controlling the movement of said frame in spaced planes, said rails being rigidly interconnected and fixed-in-place;
• (c) at least one linear motor effective to operate between one of said rails and one of said frames for moving said one frame, and at least one other linear motor effective to operate between the other of said rails and the other of said frames for moving said other frame;
• (d) roller bearings interposed between said rails and each of said opposed bearing surfaces, said roller bearings being continuously under a preload pressure that provides an interference fit;
• and
• (e) means supporting a rotary-driven spindle and drilling tool on said tied frames for rapid positioning in concert with movement of said frames by said linear motor.