Power-driven offset screw driver with torque limitation coupling has floating roller on shaft between coupling bodies, for line contact between parts and wider load distribution

摘要

The torque limitation coupling has two parts (96,90), loaded by a spring (94), and a roller body moving between the parts. The body is formed as a roller (104) located floating on a shaft (106) held on the first coupling part. The shaft defines a roller axis, which is at a distance to the longitudinal axis of the first coupling part. The shortest possible distance is between 5% and 15%, preferably between 9% and 11%, of the distance between the center of the roller and the longitudinal axis.