Bidirectional conjugate tooth profile design method for harmonic gear drive

Abstract

The invention relates to a bidirectional conjugate tooth profile design method for harmonic gear drive. The bidirectional conjugate tooth profile design method for harmonic gear drive comprises the steps of firstly, expressing a flexible wheel top-section convex tooth profile coordinate through a parameter equation, converting to a rigid wheel coordinate system, solving to obtain discrete point coordinates of a theorical conjugate concave tooth profile and a concave tooth profile of a flexible wheel top-section convex tooth profile, determining the working tooth depth of a rigid wheel tooth profile through least square fit, determining a fitted curve section to be a rigid wheel bottom-section concave tooth profile and a rigid wheel top-section concave tooth profile, and calculating to accomplish a tooth profile design of a rigid wheel; and then expressing a rigid wheel top-section convex tooth profile coordinate through a parameter equation, converting to a flexible wheel coordinate system, solving to obtain discrete point coordinates of a theorical concave conjugate tooth profile in a flexible wheel bottom-section range, determining the tooth depth of a flexible wheel through least square fit, determining a fitted curve to be a flexible wheel bottom-section concave tooth profile, and calculating to obtain a flexible wheel working tooth profile. According to the bidirectional conjugate tooth profile design method for harmonic gear drive provided by the invention, the flexible wheel tooth profile and the rigid wheel tooth profile with bi-conjugate and secondary-conjugate phenomena are directly obtained, so that a conjugate contact area and a meshing zone are increased, the tooth surface contact stress is reduced, and the drive accuracy of a harmonic reducer is improved.

Description

technical field [0001] The invention relates to the technical field of harmonic reducers, in particular to a bidirectional conjugate tooth shape design method for harmonic gear transmission. Background technique [0002] Harmonic transmission technology mainly uses the elastic deformation wave of the flexible working member to realize motion or power transmission. Due to the difference in the number of teeth between the flex spline and the rigid spline, during the rotation of the wave generator, the flex spline and the rigid spline move with staggered teeth. Thereby realizing power transmission. The tooth shape of the flexible spline and rigid spline in the harmonic reducer has a great influence on the performance. The involute tooth profile is widely used in harmonic gear transmission due to its good manufacturability, but the involute tooth profile is not a conjugate tooth profile, and the contact surface between the flexible spline profile and the rigid spline profile is...

AI Technical Summary

Problems solved by technology

[0004] In order to achieve the largest conjugate contact area and the largest meshing area, it is necessary to make CA1 and CT2 overlap. The existing design method cannot obtain such a result; although it is possible to make CA1 and CT2 by optimizing the tooth shape parameters of the flexible gear CT2 overlap as much as possible

However, because there are many parameters of the double-arc tooth shape of the flexspline, it usually requires a lot of calculations to find the appropriate parameters, which makes the design process of the double-arc tooth shape very cumbersome and takes a long time, and can only be obtained approximate result

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