Abstract

The tooth profile modification of cycloidal gears is important in the design and manufacture of precision reducers or rotary vector (RV) reducers for robots. The traditional modification design of cycloidal gears is mainly realized by setting various machining parameters, such as the size and center position of the grinding wheel. The traditional modification design has some disadvantages such as complex modification calculation, uncontrollable tooth profile curve shape and unstable meshing performance. Therefore, a new tooth profile modification method is proposed based on the consideration of the comprehensive influences of pressure angle distribution, meshing backlash, tooth tip and root clearance. Taking the pressure angle and modifications of tooth profile as the parameters of the modification function and the meshing backlash of gear teeth as constraints, the mathematical model for tooth profile modifications is built. The modifications are superimposed on the normal direction of the theoretical profile—the force transmission direction. The mathematical relationship between the modifications and the pressure angle distribution, which determines the force transmission performance, is established. Taking the straight line method, cycloid method and catenary method as examples, by means of the tooth contact analysis technology, the transmission error and minimum meshing backlash, which reflects the lost motion, of the newly modified profile are analyzed and verified. This proposed method can flexibly control the shape change of the modification profile and accurately pre-control the transmission accuracy of the cycloid-pin gear. It avoids the disadvantages of traditional modification methods, such as uncontrollable tooth profile shape and unstable meshing accuracy. The method allows good meshing characteristics, high force transmission performance and more precise tooth profile curve. The study provides a new design method of the modified profile of cycloidal gears.

Highlights

  • The transmission performance of precision reducers for robots directly affects the kinematic accuracy and repetitive positioning accuracy of robots

  • In this study, the profile of the cycloidal gear is modified according to the distribution characteristics of the pressure angle of the tooth profile curve as well as the reference point, the tooth tip and root clearance defined by the transmission accuracy index

  • The new modification design method of the tooth profile of a cycloidal gear is proposed based on the comprehensive consideration of the pressure angle distribution characteristics, the meshing backlash, the tooth tip and root clearance

Read more

Summary

Introduction

The transmission performance of precision reducers for robots directly affects the kinematic accuracy and repetitive positioning accuracy of robots. Lin et al designed a new two-stage cycloidal speed reducer with tooth modifications, studied the profile generation and modifications of cycloidal gears, analyzed the kinematic errors with the tooth contact analysis method and presented the quantitative results of different modification combinations of the gear profile [10]. Based on the mathematical theand study, on thea comprehensive consideration of the profile pressure angle, backlash, modeltipfor the profile modification of a cycloid gear,isthe mathematical relationship between the tooth and root clearance, a new modification method proposed. The study providesperformance a new way of forthe the modification and the pressure angle distribution established and the meshing modified tooth design is ofdiscussed cycloid gears in precision reducers for robots. The study provides a new way for the modification design of cycloid gears in precision reducers for robots

Expression of the Theoretical Tooth Profile
Expression of the Modified Profile of a Cycloidal Gear
Pressure Angle Distribution of Cycloid Profile
Pressure
General
Modification Calculation for the Cycloid Method
Meshing Contact Model of a Cycloid-Pin Gear
Transmission Error of the Modified Profile
Examples
11. Modification
13. Minimum
Conclusions
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.