Measurement of large gear with side gauge

The side measuring instrument is positioned and installed on the machine tool (generally installed on the tool holder) to realize the measurement of multiple errors of gears, so it is also called on-line (clinical) measurement or on-site measurement. For example, the precision gc.20hp in Osaka, Japan, and the local measuring instrument for tooth profile, tooth direction and tooth pitch of large gear studied by Dalian University of technology using the principle of electronic formula and asynchronous drive synchronous measurement; The side mounted tooth profile and tooth direction measuring device produced by hofler company of West Germany and used in conjunction with the CMM. The SM gear grinding machine produced by Maag company of Switzerland is equipped with measuring benchmarks and corresponding accessories, which can complete the on-machine measurement of tooth profile and tooth direction errors: the magnetic recording on the lateral cylindrical surface of the worktable of large precision gear hobbing machine developed by Tokyo Telecom University of Japan to realize angle measurement, The linear displacement measurement is a gear local measuring instrument installed on the tool holder of gear hobbing machine.

Like the top mounted measuring instrument, this kind of measuring instrument overcomes the limitation that the range of measuring gear of desktop measuring instrument can not be very large. At the same time, the instrument is positioned on the machine tool, so the positioning accuracy is higher than that of the top mounted instrument, so the measurement accuracy is relatively improved. This is also an important reason why people are committed to the research of this kind of gauge. It should be said that the measurement accuracy of the side mounted gear gauge has been greatly improved compared with the top mounted gauge. But there is still the problem that the original error of the machine tool affects the measurement of sugar content, and the measurement accuracy is still not high. Some scholars have begun valuable exploration in this field. For example, when measuring the tooth direction error, the “minimum self multiplication” is used to calculate the gear helix angle, which can eliminate the influence of the geometric error of the column guide rail of the machine tool on the tooth direction measurement accuracy; The positioning accuracy of the instrument is improved by establishing the compensation mathematical model.

It should be noted that the side gauge based on the machine measurement method has great advantages in measuring super large gears, but the measurement technology needs to be developed. In order to realize the real on-line (clinical) measurement, we must explore new cutting technology and measurement methods, including error correction of key parts of the machine tool, and take the workpiece benchmark as the measurement benchmark, so as to achieve the purpose that the machine tool error does not affect the measurement accuracy.