| 摘要 |
PROBLEM TO BE SOLVED: To provide a detecting device for the number of stretching capable of more securely detecting the number of stretching with a simple configuration. SOLUTION: The detecting device for the number of stretching is provided between a boom point sheave 5 of a winding-up wire rope 9 and a hook 6. The device includes a first limit switch 10 energized and operated by rising of the hook 6, an elapsed time measuring means 31 for measuring elapsed time for winding up the hook 6 from a predetermined height to a height for energizing the first limit switch 10, and a stretching number determination means 33 for determining the number of stretching of the winding-up wire rope 9 based on the elapsed time measured by the elapsed time measuring means 31. COPYRIGHT: (C)2009,JPO&INPIT
|
