Minneapolis, MN, - A new way to check out rotational deviations on the sophisticated coordinate measuring machines produced by Carl Zeiss, Inc.'s IMT Division reduces inspection time by two hours per machine.
According to Brad Hanneman, Calibration Group Leader at the IMT manufacturing plant, "I know of no other rapid way to correct rotational devices. This is an operation that used to require lengthy measurements using mechanical indicators on a master reference plus long and drawn-out calculations to correct these deviations."
The instrument is a special 2-D Fowler/Wyler measuring system designed to measure CMM geometry. The X-Y reference level is set on the CMM surface plate and the Wyler transducer is mounted on the coordinate measuring machine probe receptacle.    
The transducer sends out a signal and IMT takes the signal from a Hewlett-Packard multimeter, recording the rotational deviation of the X-axis. This information is sent to a computer system which produces proprietary computer-aided accuracy software.
"The system generates a file that corrects any rotational error detected by the Wyler system," Hanneman adds.

Zeiss uses the new system, supplied by Fred V. Fowler Company, exclusive US agent for the Wyler products, to insure the accuracy of its "Prismo Vast" (Variable Accuracy and Speed Probing Technology) coordinate measuring machine. This CMM, whose probe head combines single point and scanning probing technologies, enables form and position inspections to be done on the same CMM that measures linear dimensions. It gives form tolerances that can be measured up to an accuracy of 0.0017mm scanning at 5mm/second. Scanning at 20mm/second accuracy is 0.0034mm. Because of its new active interface, VAST can provide automated temperature measurement as well.Reduction of two hours inspection time per machine has offered higher productivity and quality.
Zeiss uses the 2-D Fowler/Wyler measuring system on several different models of its CMMs. On occasion, Hanneman reports it is also used in the field to check proper machine performance and make all necessary corrections after the CMM is delivered.

Customers for these coordinate measuring machines include General Motors, Honda, Pratt & Whitney, and John Deere, among others. "In a nutshell," concludes Hanneman, "we can now correct rotational deviations electronically from information supplied by the Wyler system. It's a neat solution to a complicated problem."