Abstract
The frictional force acting on the vertical synchronous belts used in hauling upthe net or rope and the main factors affecting the frictional forces were determined through experimental and theoretical analysis. The frictional force was calculated by using Euler's equation. It was shown that the average frictional coefficient between belt and net was 0.78 and that between belt and rope was 0.70. When the net or rope was wound out by belts along a spiral line, the frictional force wasfound to decrease with an increase in the spiral angle. At a constant velocity, the speed of moving up the net or rope had no effect upon the frictional force. On the other hand, a non-uniform velocity of moving reduced the actual frictional force.
