| 摘要 |
PURPOSE: To constantly keep a load-carrying platform at a constant level by connecting a wire rope length correcting device to an end of a wire rope, and interlocking the length correcting device based on a detection signal of a level detection device to detect a stop position of a load-carrying platform. CONSTITUTION: As a load-carrying platform 24 gets under a specified stop position as indicated by a supposed line till a contact 2a of a limit switch 2 gets in contact with a lower slide surface 4a2 , a solenoid SOL2 of a solenoid control valve 5 is energized to pull up a rod 1a of an operation cylinder 1, and as a result, the load-carrying platform 24 is pulled up for a lowered stroke. On the contrary, when the load-carrying platform 24 gets above the specified position till the contact 2a of the switch 2 gets in contact with an upper slide surface 4a1 of the cam 4, the load-carrying platform 24 is automatically lowered for a raised stroke. Since a wire rope length correcting device A is thus interlocked based on a detection signal by a level detection device B comprising the switch 2 and the cam 4, the load-carrying platform can thus be held at a specified stop position regardless of change of carrying load. |
