| 摘要 |
PURPOSE:To prevent the dropping of a gate under its own weight by providing a clutch to prevent the closing direction rotation of a rotary shaft and a clutch to prevent the opening direction rotation of a handle to a boosting part for opening operation of a gear type booster between the handle and the rotary shaft for vertically moving the gate. CONSTITUTION:A manual operator is made up of a rotary shaft 7 and a handle 5 interlocking with a vertically movable gate 2, gear type boosters A and B, and an open, close, neutral switch type clutch C to disconnect the handle 5 and the rotary shaft 7. The gear type booster is made up of a booster A having a worm gear 16 for closing operation and a booster B consisting of flat gears 22 and 23 for opening operation. A clutch 24 to prevent the closing direction rotation of the rotary shaft 7 and a clutch 25 to allow the closing direction rotation of the handle 5 are provided to the booster B. The opening and closing operations by the handle are improved and the lowering of the gate under its own weight can be prevented. |
