PROBLEM TO BE SOLVED: To provide a helical prevention device, easily downwardly movable on a branch line.SOLUTION: A helical prevention device 1 is installed in a branch line 110 extending upward from the ground surface, and comprises a case body 10, a pair of rotary members 32 and 34 rotatably supported inside the case body 10 by a pair of rotary shafts 36 and 38 and gripping the branch line 110 of passing through the inside of the case body 10 from both sides and a wire member 50, and the rotary members 32 and 34 are composed of eccentric bodies 32a and 34a having projection parts 32d and 34d and sector gears 32b and 34b fixed to the eccentric bodies 32a and 34a and interlocking the rotary members 32 and 34 so that the tips of the projection parts 32d and 34d mutually approach and separate, and the wire member 50 is fixed in one end part to the projection part 32d, and is pulled out in the other end part to an external part from the case body 10, and a width between the tips of the projection parts 32d and 34d becomes larger than a thickness of the branch line 110 by pulling the other end part of the wire member 50.COPYRIGHT: (C)2015,JPO&INPIT【課題】支線上において下方に移動することを容易に可能にした蔓巻防止装置を提供すること。【解決手段】地表から上方に延びる支線110に設置される蔓巻防止装置1であって、ケース体10と、ケース体10の内部に一対の回転軸36、38によって回動自在に支持され、ケース体10の内部を通る支線110を両側から把持する一対の回動部材32、34と、ワイヤ部材50と、を備え、回動部材32、34は、突出部32d、34dを有する偏心体32a、34aと、偏心体32a、34aに固定され、突出部32d、34dの先端が互いに接近及び離間するように回動部材32、34を連動させるセクタ歯車32b、34bとからなり、ワイヤ部材50は、一端部が突出部32dに固定され、他端部がケース体10から外部に引き出され、ワイヤ部材50の他端部を引っ張ることにより、突出部32d、34dの先端間の幅が、支線110の太さより大きくなる。【選択図】図2
