Research On Short Harmonic Gear Drive

With the development of aerospace, greater demand will be set on harmonic gear driving device. Because the size in axial direction is big, the common harmonic gear driving device with cup-shaped flexspline can't satisfy the demand of assemble space. Also harmonic gear driving device with ring-type flexspline has a short axial direction size, but it has the problems of low transmission efficiency and low carrying capacity. So the domestic harmonic gear driving device still can't meet all the strict demands of aerospace on the facts of assemble space, quality, distortion etc. at the same time. The harmonic gear driving device with short cup-shaped flexspline can meet all the demands mentioned above at the same time, but only several developed country can grasp the design of this kind of transmission device.Though there're advantages of the harmonic gear driving device with short cup-shaped flexspline, it has to deal with the problem of the stress sharp increasing.In order to improve the performance of harmonic gear driving device, the harmonic gear driving device with short cup-shaped flexspline is studied. The main works include:(1) The size of the main components of harmonic gear driving device is designed and modeling and assembling of harmonice gear driving device with solidworks is also finished.(2) The influence of geometric parameters, including slenderness ratio, the thickness, gear ring width, gear ring frontier width, the knuckle between flexspline bottom and flange, the size of the flange, to the stress distribution is studied.(3) The contact analysis model between flexspline with equivalent gear and cam wave generator is established. And the thought that flexible bearings of cam wave generator can be modificated is put forward. And the relation between the maximum equivalent stress of flexspline and the size of cam wave generator at no-load is concluded. The influence of modification of cam wave generator to the carrying capacity of flexspline is studied(4) The quarter contact analysis model between flexspline with complete gears and cam wave generator is established and the stress of short cup-shaped flexspline is studied.Final, the harmonic gear driving device with short-cupped flexspline is designed. The stress of flexspline can be reduced, by the optimizing of the flexsline's geometric parameters and the modification of cam wave generator. The result shows that it can meet the requirment.