Study on the grinding technology and measure method for planar enveloping hourglass worm

Abstract

In order to accelerate the engineering application of planar enveloping hourglass worm drive, a grinding method of planar enveloping hourglass worm tooth surface is proposed. Based on the generating of planar enveloping hourglass worm tooth surface, the actual rotation center grinding principle is analyzed and the mathematical model of tooth surface is deduced. The novel virtual rotation center grinding principle for planar enveloping hourglass worm tooth surface is proposed based on the rigid body movement, and the movement control methods of the four motion axes are studied. The key technologies of tip relief and thickness control of planar enveloping hourglass worm tooth surface are provided, and an hourglass worm grinding machine structure is proposed based on the virtual rotation center grinding principle. A measuring method is presented to evaluate the tooth surface accuracy of planar enveloping hourglass worm, and the data gaining and data processing are studied. A planar enveloping hourglass worm sample is ground and a prototype is manufactured, as well as the accuracy measurement and performance test are carried at last. The results show that the tooth surface accuracy of this sample is up to level 5, while the short-period transmission error of this prototype is 21.7 arcsec, and this grinding method is correct and effective. This theoretical and experimental research lays the foundation for the industrial application of planar enveloping hourglass worm drive.