Novel measurement standard for internal involute microgears with modules down to 0.1 mm

Abstract

Involute microgears are important components used in industrial applications. Quality control benefits from enhanced, monitored measurement processes. Workpiece-like measurement standards help to verify measurements and estimate measurement uncertainties by comparing the geometrical values measured with the calibration values. To address the need for reliable, traceable gear standards on the microscale, Germany’s national metrology institute, the Physikalisch-Technische Bundesanstalt, has developed the first internal involute microgear measurement standard with modules between 0.1 and 1 mm. We manufactured two versions with different materials (titanium and carbide) by means of wire electrical discharge machining. Profile and flank deviations were calibrated with sub-micrometer uncertainty by means of tactile scanning measurements using a micro coordinate measuring machine. This paper features information on the design, manufacturing, and calibration processes, including a detailed measurement uncertainty budget.