摘要 |
PROBLEM TO BE SOLVED: To achieve smooth braking with little shock by improving the detecting accuracy and reliability in a safety device for an elevator for construction. SOLUTION: This safety device for an elevator for construction automatically stops lowering of a carrier in the case of abnormal condition where the descending speed exceeds a preset value. An eccentric sprocket 21 provided to rotate according to a detection signal of the descending speed is provided on the carrier side, and a stopping means is provided to stop the carrier when teeth 23 of the eccentric sprocket 21 mesh with rack teeth 16 like wedge to increase the meshing pressure and the turning torque of the eccentric sprocket 21 rises. The safety device includes a lock means 30, which normally engages with the eccentric sprocket side, whereby the eccentric sprocket 21 is regulated to a position not meshing the rack teeth 16, and in the case of the abnormal condition, the engagement state with the eccentric sprocket side is released based on the detection signal of the descending speed, to enable rotation of the eccentric sprocket 21. COPYRIGHT: (C)2008,JPO&INPIT |