Hourglass Worm Gearing with Worm Teeth Generated by High-Speed Screw Cutting Method

Authors reported theory of hourglass worm gearing whose worm is generated by high speed screw generating method, on previous report. CNC high speed hourglass worm generating machine has been developed according to the theory. And worm cutting test and performance test of worm gearing was made. The test results are as follows: (1) Newly developed machine has high speed cutting ability same as mach type screw generating apparatus. (2) Surface roughness of worm tooth surface generated by the CNC high speed hourglass worm generating machine has same order of roughness of screw surface cut by mach type screw generating apparatus. (3) Hourglass worm gearing generated by the newly developed machine showed high efficiency and ran 1000 hours without trouble.