Manufacturing and contact characteristics analysis of a novel 2K-H internal meshing planetary reducer with involute-cycloid combined tooth profiles

Rotate Vector (RV) reducer involves multiple crankshafts to drive the cycloidal-pin transmission in parallel, leading to an over-positioning structure and high manufacturing and assembly requirements for the reducer, restricting the development of industrial robots. In view of the above problems, a novel configuration of Abnormal Cycloidal Gear (ACG) reducer with a 2K-H internal meshing planetary transmission is proposed. The design innovatively replaces the multiple crankshafts with a pin mechanism, thereby addressing the over-positioning and simplifying the manufacturing and assembly processes. To improve the performance of the reducer, the “epicycloid-involute-hypocycloid” combined tooth profiles are designed and adopted as the ACG reducer’s drive teeth. The configuration principle of the ACG reducer is conducted. Next, a manufacturing method utilizing a rack cutter to generate the profile of drive teeth is presented. Finally, the meshing performance and mechanical behaviors of the designed internal meshing pair for the ACG reducer are evaluated. Results show that ACG reducer has the advantages of a simple structure and large transmission ratio. The combined tooth profiles can be machined at one time using the designed cutter, simplifying the tooth machining process. The internal meshing pair is linear contact and exhibits an obviously multi-teeth meshing effect, which benefits the carrying capacity and transmission performance of the ACG reducer.