Abstract
We have developed the world's fastest elevator at a speed of 1200m/min. Safety gears are important devices in the speedup. The safety gears stop the car at the time of emergency by pushing brake wedges to guide rails. A huge amount of frictional heat between brake wedges and guide rails is generated by the speedup, and the surface temperature of guide rails rises. By the temperature rise, the coefficient of friction becomes small, and braking forces decrease. To solve this problem, we developed an analysis technology to estimate the coefficient of friction drop by the temperature rise. It is clear that the drop of the coefficient of friction can be suppressed by dividing a bake wedge into two, and putting the moderate interval between two brake wedges. We show by a drop test that we were able to stop the lift in the deceleration according to design, and that the average deceleration is within a range set by European Norm.
