Multi-point-contact flexible bearing for harmonic reducer

Abstract

A multi-point-contact flexible bearing for a harmonic reducer comprises a three-point-contact flexible ball bearing, a four-point-contact flexible ball bearing and a line-contact flexible roller bearing; a single rolling body and an outer ring raceway, namely, an outer ring-flexible gear interference-fit piece have two or more contact points; compared with the prior art that only one contact point exists, the multi-point-contact flexible bearing has the quality and technological advantages that the given deformation precision of the outer ring-flexible gear interference-fit piece and the meshing precision of flexible gear teeth with rigid gear teeth are improved, unnecessary additional deformation is reduced and even avoided, the contact stress of the rolling body with the raceway is reduced, sliding of the rolling body is controlled, assembling conditions and lubricating conditions of the bearing during operation are improved, and the like; and finally, the running precision and the service life of the flexible bearing, a flexible gear and even the whole harmonic reducer are improved and prolonged, and the bearing has very important actual engineering significance.

Description

technical field [0001] The invention relates to the technical field of special rolling bearings, in particular to a multi-point contact flexible bearing for a harmonic reducer and a flexspline tooth low additional deformation wave generator-flexspline assembly using the bearing. Background technique [0002] Harmonic gear reducer (hereinafter referred to as harmonic reducer) is an advanced and precise reducer, due to its outstanding advantages such as small size, light weight, small hysteresis, high positioning accuracy and transmission efficiency, and easy realization of precise position control It is widely used in precision machinery fields such as industrial robots, high-end cars, aerospace, optical instruments, and high-end printing machines. With the rise of intelligent manufacturing centered on industrial robots, harmonic reducers, together with RV reducers, have been widely valued by countries all over the world because of their inherent advanced nature. [0003] Th...

AI Technical Summary

Problems solved by technology

The current flexible bearing is a single-row shallow groove radial ball bearing, and there is only one contact point between the ball and the grooved raceway of the outer ring (hereinafter referred to as the grooved raceway for short) and the raceway of the inner ring, so there are the following problems: (1 ) The external force that forces the outer ring-flexspline interference fit to undergo periodic bending deformation is the contact force between the ball and the outer ring groove. On one of the cross-sections of the cross-section, there are two problems, one is that the required contact force is too large for a given deformation, and the other is that the outer ring of the bearing and the flexspline inevitably occur along the outer ring of the bearing or the flexspline. The warping deformation in the tooth width direction and the twisting deformation in the circumferential direction will affect the meshing accuracy and transmission efficiency of the flexible spline and the rigid spline; (2) The stiffness of the bearing in the axial and angular directions is very low. Once the external load exists in the axial direction and angular components, the bearing rings and balls will undergo deformation and displacement required for non-flexible bearing functions along these two directions, which reduces the transmission efficiency and transmission accuracy of the harmonic reducer; If the constraint is not enough, a large amount of sliding components will be generated in the ball movement, which will cause the abrasion of the bearing working surface and the deterioration of the bearing accuracy.

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