PROBLEM TO BE SOLVED: To provide a diameter-reducing operation pipe structure in which the diameter-reducing operation of a loop-shaped capture wire is made as quick as possible to easily catch a prey. SOLUTION: Two wire insertion pipes which penetrate the left and right free end wires of a capture wire having a loop portion formed ahead to capture a leg of a harmful animal, and a wire guide body provided at the tip of the pipe. And a wire stopper function body which is provided at the rear end of the pipe and can pass the capture wire only in the loosening direction and is fixed and fixed in the pulling and tensioning direction of the wire, and a wire guide body and a wire stopper in the wire insertion pipe. It is composed of a winding spring that is compressed between the function body and the trapping wire inserted in the hollow part of the winding spring. With the wire stopper function body, a diameter-reducing operation pipe structure of a loop-shaped capture wire used for a pest capturing device that is configured to be pulled and fixed to perform the diameter reduction operation of the loop portion as quickly as possible. [Selection diagram] Figure 2【課題】ループ状の捕獲ワイヤの縮径作動を可及的に迅速化して獲物を捕獲しやすい縮径作動パイプ構造を提供する。【解決手段】害獣の脚部を捕獲するために先方にループ部を形成した捕獲ワイヤの左右自由端ワイヤを挿貫した二本のワイヤ挿通パイプと、該パイプの先端に設けたワイヤガイド体と、該パイプの後端に設け捕獲ワイヤを弛緩方向にのみ通過可能でワイヤの引っぱり緊張方向では止着固定すべく構成したワイヤストッパー機能体と、ワイヤ挿通パイプ中において、ワイヤガイド体とワイヤストッパー機能体との間に圧縮介在した巻きバネとより構成し、しかも巻きバネの巻き中空部に捕獲ワイヤを挿通することでループ状の捕獲ワイヤの左右自由端ワイヤを圧縮した巻きバネのひっぱり付勢によりワイヤストッパー機能体を介して、引っ張り止着し、ループ部の縮径作動を可及的迅速に行うように構成した害獣捕獲具に用いるループ状捕獲ワイヤの縮径作動パイプ構造。【選択図】図２
