Rapid Measurement of Involute Profiles for Scroll Compressors

Abstract

Scroll compressors are widely used in air conditioners, vacuum pumps and so on. Rapid measurement of flank profile of a scroll compressor is important to improve the compression efficiency and decrease noises. A contact probe made of ruby was used for measurement of flank profile. The probe was moved by a linear slide along the X axis at a constant speed. The scroll workpiece was fixed on a precision rotary stage. The relationship between the stage rotational speed and the X axis moving speed complies with the Archimedean curve. The measurement data of the rapid measurement system were analyzed and measurement errors were removed by compensation of the offset between the coordinates of the rotary stage center and those of workpiece center. The measurement results were compared with those measured by a commercial coordinate measuring machine (CMM). The measurement time for the involute profile of the scroll is shortened to 153 seconds by the developed rapid measurement system from the 10 minutes measurement time by the CMM while the measurement accuracy is kept the same.

Outlier Detection and Correction for the Deviations of Tooth Profiles of Gears

“…The measurement of tooth profiles is a difficult measurement item, and now tooth profiles are usually measured by gear measuring center [3][4][5]. Gear measuring center is a kind of efficient precision measuring instrument, but outliers easily cause sudden measurement environment changes in the measurement of tooth profiles, such as the effect of mechanical vibration on the measuring head and the impact of the sharp current on the data acquisition card [6][7][8].…”