Abstract: An apparatus for converting rotary motion to translatory motion. The apparatus contains shaped rollers located therein so that the longitudinal axis of the rollers forms an acute angle with the longitudinal axis of a shaft passing through the apparatus. The rollers are contained in a cylindrical housing having end pieces. The rollers are shaped to have maximum contact with the shaft. Roller race means and spring means contained within the housing retain the rollers and provide a load to maintain tight shaft to roller contact. Rotation of the apparatus about a shaft causes a shaft to move in a longitudinal direction, while rotation of the shaft within the apparatus causes the apparatus to move in a longitudinal direction.

Abstract: A method of abrading and simultaneously coating at least one surface of an article, particularly a circuit board assembly. The method comprises introducing abrasive particles into the compressed gas supply of a spray gun. The resulting gas stream with entrained abrasive particles is transported to and emitted from at least one spray nozzle of the spray gun where it is directed to the surface of the article with a film-forming coating composition stream also directed to and emitted from at least one nozzle of the spray gun. The abrasive particles can be simultaneously sprayed along with the optional coating composition onto the surface (these abrasive particles being microballoons in the case of a circuit board assembly). The surface is abraded while the coating is being applied. The resulting coating is substantially free of abrasive articles and has good adherence to the surface.