Patent ID: 7073271

Claim:
A portable coordinate measurement machine (CMM) for measuring the position of an object in a selected volume, comprising: a manually positionable articulated arm having opposed first and second ends, said arm including a plurality of rotary joints; a measurement probe attached to a first end of said articulated arm; an electronic circuit which receives the position signals from transducers in said arm and provides a digital coordinate corresponding to the position of the probe in a selected volume; and wherein at least one of said rotary joints comprises; a rotatable shaft; at least two spaced bearings; a periodic pattern of a measurable characteristic; at least one read head spaced from and in communication with said pattern; a housing surrounding said at least two bearings, pattern, read head and at least a portion of said shaft so as to define a singular component and wherein races for said bearings are formed by at least one of the following: (1) said shaft constitutes the inner race of at least one of said two bearings and (2) said housing constitutes the outer race of at least one of said two bearings; said pattern and said read head being associated with said shaft and housing such that said pattern and read head are rotatable with respect to each other; and wherein said singular component includes the functionality of measuring rotation, supporting rotation and transferring rotation.