PRECISION BORE MACHINE AND METHOD OF PRODUCING A PRECISE BORE
A bore machine for producing a very precise bore, as well as a method of producing a very precise bore in a workpiece. The bore machine has a main drive that drives the spindle rotationally as well as travel along the axial direction and an auxiliary drive that provides an oscillating motion in the axial direction that is overlayed over the forward travel motion of the spindle. The auxiliary drive has a first element with a wave-shaped surface and that is movable relative to a second element. During relative motion between the first and second elements, one element is forced to follow the peaks and valleys of the wave-shaped surface, thereby generating the oscillating motion. The auxiliary drive is driven such, that the relative motion between the two elements is at most 30% of the rotational speed of the spindle.
1 . A bore machine for machining a very precise bore, the bore machine comprising:
a spindle for holding a bore tool, the spindle having a longitudinal axis;
a main drive that drives the spindle to rotate and to move in an axial direction in forward travel and in return travel;
an auxiliary drive that generates an oscillating motion in the axial direction and that is overlayed over the forward travel of the spindle, the auxiliary drive including a first element and a second element, the first element having a wave-shaped surface and being movable relative the second element;
wherein, during motion between the first element and second element relative to each other, the second element is driven to follow wave peaks and wave valleys of the first element to generate the oscillating motion; and
wherein the first element and second element are driven such, that motion relative to each other is at most 30% of the rotational speed of the spindle.