| 摘要 |
An external gear (4) of a dual-type wave gear device (1) is provided with first and second external teeth (7, 8), the numbers of which differ, and gaps (9) formed therebetween that serve as the cutter clearance areas for a tooth-cutting cutter. The maximum width (L1) of the gaps (9) is 0.1-0.3 times the width (L) of the external gear. The depth from the tooth crests of the first external teeth (7) to the deepest area (9a) of the gaps (9) is 0.9-1.3 times the tooth depth of the first external teeth. The depth from the tooth crests of the second external teeth (8) to the deepest area (9a) is 0.9-1.3 times the tooth depth of the second external teeth. The tooth root fatigue strength of the external gear provided with differing numbers of first and second external teeth is increased, making it possible to achieve a wave gear device with high load capacity and small speed ratio. |
