| 摘要 |
An upper part protecting apparatus of an observation hole is provided to prevent an upper part of the observation hole from being contaminated by an extension pipe, and to install a sensor easily by mounting a pulley unit. An upper part protecting apparatus of an observation hole comprises an extension pipe(101), a cover(105), and a pulley member(171). The extension pipe is extended to the observation hole, and flanges(103) are formed on the upper end of the extension pipe. The cover is rotatably installed to the extension pipe through a hinge unit(120) to close the upper part of the hole by sealing the upper end of the extension pipe. The pulley member is installed to the cover to install a sensor easily and to increase pulling work. The pulley member is placed at the center of the extension pipe. A wire guiding member(181) is folded on the inner surface of the extension pipe. |
