Abstract
Mechanical elements such as rope and pulley systems are widely used in elevators and hoist machineries. For these machineries, it is necessary to perform the behavior analysis for emergency stop in order to ensure safety. "Slip" may occur between the rope and the pulley at the emergency stop, and it depends on the frictional characteristics. Since behavior of the contact between the rope and pulley is complex, it had not been studied enough so far. In this study, we propose a simple modeling of the rope and the pulley by spring-mass system through multi-degree-of-freedom approach. In the model, friction is acting on each mass. Numerical simulation is performed to evaluate the slip distance. In this study, the condition for the rope finally stopping at the emergency brake is investigated. Otherwise, the rope does not stop and it falls. We solve the equation of motion numerically by the Runge-Kutta method with fourth order.
