Spherical contact pairs influence on azimuth error of the column load sensor
                                           CHEN Jun xiang1, LIANG Wei1,2, YANG Xiao xiang1,3, YAO Jin hui2
(1.College of Mechanical＆Automotive Engineering, Fuzhou University, Fuzhou 350116, China;2.Fujian Province Institute of Metrology, Fuzhou 350003, China;3.Quanzhou Normal University, Quanzhou 362000, China)

Abstract: Aiming at control of the column load sensor s azimuth error, the impact of changes of spherical contact pairs spherical surface sizes was studied. The additional bending moment was proven to be a major source of the load sensor s azimuth error and the influence rule of changes of spherical surface sizes on additional bending moment and azimuth error of the sensor was discovered by derivation of mechanical formulas. The typical spherical plane contact type and the spherical surface size were confirmed from common size range, the compression simulation of the sensor was carried out by ABAQUS and then the rule was validated by load characteristic experiment. The results indicate that spherical plane spherical contact pairs can effective reduce additional bending moment and azimuth error of the column load sensor. Additional bending moment the sensor suffers will decrease and improvement of the load sensor s azimuth error will be more and more significant while selecting smaller sphere diameter R1.

Key words: column load sensor; azimuth error; spherical contact pairs; additional bending moment