Dividing head

摘要

An apparatus and method for rotationally moving and positioning a work piece such as for dividing the workpiece into a predetermined number of equal segments. The movement is accomplished by repeatedly angularly displacing the work piece over a given swing increment of angular movement. The angular swing increment is established by summing angular displacements of each of a plurality of circular plates, each plate divided into a different number of equal segments. By a proper choice of the number of segments into which the plates are divided, and of the number of segments each plate is displaced, the angular increment can be established with extremely high precision. The angular increment may be greater than the distance between adjacent intended segments into which the work piece is divided. This allows distribution of the error of the angular increment established for each movement of the work piece about the entire periphery of the work piece, minimizing the accumulation of error between any particular pair of segments into which the work piece is divided. Additionally, a spanner disc is provided for allowing additional angular movement of the work piece within a secondary angular increment on either side of positions achieved by means of the aforesaid angular increments. This apparatus and method can be employed in any application requiring precision indexed rotational position for any purpose.