| 摘要 |
PROBLEM TO BE SOLVED: To improve the detection accuracy, and save the space by attaching a magnetic scale in which an N pole and a S pole are alternately magnetized on an outer circumferential surface of a sheave of a hoist, and providing a magnetic sensor on a part of the hoist opposite to the magnetic scale to directly detect the rotation of the sheave. SOLUTION: A recessed part (or a projecting part) 6 is provided on a part of a sheave 3, and a magnetic scale 7 in which an N pole and a S pole are alternately magnetize, is mounted on the side thereof. A magnetic sensor 9 is arranged at the position opposite to the magnetic scale 7 with an interval therebetween on an arm 8 on the fixed side. When a motor is driven by the operation command of an elevator, and the sheave 3 is also turned, the magnetic scale 7 is also turned. The magnetic sensor 9 provided on the fixed side detects the N pole and the S pole of the magnetic scale 7. The signal is processed as the ON signal and the OFF signal by a microcomputer in a control panel, and used for the positional signal of the elevator through addition and subtraction according to the turning direction of the sheave 3, and used for the speed control and the position control. |
