Method of cutting a fine screw thread to function as a lead screw in producing another fine screw thread

摘要

708,539. Screw and nut gearing. NATIONAL RESEARCH DEVELOPMENT CORPORATION. May 9, 1952 [May 9, 1951], No. 10952/51. Class 80 (3) A screw for co-operating with a nut of elastic material as described in Specification 684,846, to provide a uniform relative axial movement between the screw and nut on relative rotation thereof, is formed as a composite thread by a plurality of individual cutting elements 2a-f which cut or inscribe a plurality of short lengths h1-6 of a continuous thread of the screw 1 so that traverse of each element is only a small fractional part of the total length of thread whereby the incidence of progressive error in the traversing screw 3 is minimized. The plurality of individual cutting elements may be constituted by an abrasive material which is applied to the cylindrical surface of the screw 1.