Non-contact coolant supply apparatus

A non-contact coolant supply apparatus for a cutting tool for cutting a workpiece wherein there is relative cutting motion about an axis of rotation between a cutting member mounted upon a tool shank, said shank having at least one helical coolant passage opening in the outside diameter of the tool shank, and an annular groove formed therein and a workpiece;

• wherein coolant is supplied from a coolant supply means through a ring bore defined by ring bore walls which extend from an outer peripheral surface to an inner peripheral surface of a coolant supply ring which is fixedly mounted;
• said tool shank passing through said coolant supply ring with a close clearance therebetween such that the inner peripheral surface is positioned directly over, and circumferentially surrounds said annular groove in the tool shank so that coolant is introduced through the ring bore to the annular groove on the tool shank, and the rotation of the tool shank causes the helical coolant passage to act as an impeller to force the coolant through the helical coolant passages and into close proximity to the cutting members.