Design, Specification and Tolerancing of Micrometer-Tolerance Assemblies

摘要

Increasing numbers of economically important products manufactured by U.S.companies are comprised of assemblies of component parts which have macroscopic dimensions and microscopic tolerances. Micrometer-tolerance assemblies include not only integrated-circuit devices and mangetic-memory read-write heads, but automobile-engine systems, including fuel injectors, hydraulic valve lifters and even piston and cylinder assemblies. Focusing on these, this paper: (1) reports examples of micrometer-tolerance assemblies; (2) discusses strategies in design, specification, and tolerancing (DS&T) which some companies have adopted for the manufacture of such assemblies; and (3) identifies generic-technology, measurement, and standards issues in DS&T associated with that manufacture.