A dimensional measuring system, the profile monitor, has been developed to measure part dimensions with a standard deviation of 0.0001 inch at a throughput rate of 1200 parts/ minute. The monitor is one measurement system on an advanced high speed inspection system designed to monitor the production of cartridge cases. The complete system includes a mechanical handler, measurement instruments (which make five measurements), system monitoring instruments and a dedicated minicomputer. This paper describes the profile monitor and its performance. The profile monitor is an electro-optic system that utilizes fiber optics to project an image of the case onto charge-coupled device image sensors. Measurements are made for five different case dimensions: 1) head thickness, 2) head diameter, 3) extractor groove diameter, 4) gas seal length and 5) total length. The profile monitor consists of five major elements: the case gauging fixture, the optical system including an illumination source and folding optics, the diode array (detector), the processing electronics and the computer. Electronics consist of the diode array and driver, thresholding circuit, measurement timing logic and data buffers. The square image conduit (six micron fibers) is structured to take the edges of the projected case image and transfer the image to a 0.125 inch linear charge coupled device (CCD) sensor. Logic is employed to detect the shadowed edges of the case and count the number of elements darkened by the shadow.

Date Published: 29 November 1979
PDF: 9 pages
Proc. SPIE 0193, Optical Systems in Engineering I, (29 November 1979); doi: 10.1117/12.957902

Published in SPIE Proceedings Vol. 0193:
Optical Systems in Engineering I
Paul R. Yoder Jr., Editor(s)