| 摘要 |
PROBLEM TO BE SOLVED: To provide an elevator capable of predicting a change in limit tension ratio.SOLUTION: An amount of displacement between a sheave 6 and a main rope 4 is detected by a displacement amount computing device 13. A ratio of tension applied to both ends of the main rope 4 is computed by a tension ratio computing device 14. A limit tension ratio of the main rope 4 is computed by a limit tension ratio prediction device 15, on the basis of the computed amount of displacement and the computed tension ratio. The computed amount of displacement, the computed tension ratio and the computed limit tension ratio are stored in a storage device 16. A prediction about a change in the limit tension ratio is computed by the limit tension ratio prediction device 15, on the basis of a difference between the limit tension ratios stored in the storage device 16 and a total movement distance of a car 3, which is measured by a car movement distance measurement device 10. |
