Patent ID: 6305503
Filing Date: 2001-10-23
Classification: B66B

Abstract:
A load detector for an elevator having a cable placed around a sheave driven by a motor, said cable hanging a weight and a cage moving up and down in a shaft for transporting passengers, comprising:a brake having a housing, a brake disk secured to a rotary shaft of said motor, and a brake shoe for pressing said brake disk toward an elastic ring disposed between said brake shoe and the inside wall of said housing and stopping the revolution of said sheave;a strain detector attached to said elastic ring and configured to detect a torsional strain of said brake disk caused by an unbalance in weight between said cage and said weight; anda calculator configured to calculate a change of said torsional strain between a torsional strain just after said cage lands at a floor and a torsional strain just before said cage leaves said floor, and a load of said cage on the basis of said change of said torsional strain.