Device for treating the surface of a workpiece

Claim 1

A DEVICE FOR TREATING THE SURFACE OF A WORKPIECE COMPRISING A NOZZLE, SAID NOZZLE HAVING A CONVERGENTDIVERGENT CONTOUR TERMINATING IN AN OPEN EXIT APERTURE FOR DISCHARGING DIRECTLY THEREFROM AGAINST AN ADJACENT OBJECT, MEANS FOR SUPPORTING A WORKPIECE ADJACENT SAID EXIT APERTURE OF SAID NOZZLE, A SOURCE OF COMPRESSED AIR, CONDUIT MEANS CONNECTING SAID SOURCE OF COMPRESSED AIR TO SAID NOZZLE FOR DISCHARGE FROM SAID NOZZLE, SAID AIR BEING UNDER PRESSURE SUFFICIENT TO CREATE A SUPERSONIC VELOCITY UPON SUCH DISCHARGE, A SOURCE OF AIR AND FINELY DIVIDED COATING MATERIAL, SAID LAST-MENTIONED SOURCE OF AIR BEING AT A RELATIVELY LOWER PRESSURE THAN SAID FIRSTMENTIONED SOURCE OF AIR, SAID SOURCE OF AIR AND COATING MATERIAL BEING CONNECTED TO SAID NOZZLE FOR MIXING THEREIN WITH SAID FIRST-MENTIONED SOURCE OF AIR, WHEREBY WHEN SAID NOZZLE EXIT APERTURE IS DIRECTED TOWARD THE SURFACE OF A WORKPIECE, SAID FINELY DIVIDED COATING MATERIAL IS CAUSED TO STRIKE SAID WORKPIECE AT A SUPERSONIC VELOCITY AND A QUANTITY OF SAID MATERIAL ADHERES TO SAID SURFACE AND FORM A COATING THEREON.