In view of the influence of the clearance of 7 hinge points of MCCB operating mechanism on the dynamic characteristics of the mechanism

18 groups of simulation experiments are designed by using the orthogonal experimental design method. The influence of the each clearance point on the indexes of the operating mechanism is obtained through the range analysis. The comprehensive evaluation function is established by combining the weighted sub objective multiplication and division method. Finally

the dynamic contact rod is in terms of the acceleration and stress analysis of the lower connecting rod

the simulation and comparative analysis without clearance and with clearance are made. The results show that if the influence of the clearance of the moving pair is ignored in the simulation

the maximum deviation of the simulation values of each index is 49.45%

and the average deviation is at least 5%. The clearance point with the greatest comprehensive impact on the MCCB operating mechanism is the connecting shaft clearance between the push-pull rod and the upper connecting rod. The dynamic simulation under the ideal hinge chain

its displacement change

stress distribution and basic change trend can be used for reference

while the speed characteristics

acceleration characteristics The maximum stress value and the occurrence time of the maximum stress will deviate from the reality.