PROBLEM TO BE SOLVED: To provide a liquid administration tool capable of arbitrarily adjusting an administration speed and reducing a burden on a user.SOLUTION: A liquid administration tool 10 includes an operation part 20, a structure 40 comprising a syringe 60 and a needle tube 66 and movable with respect to the operation part 20, a cover member 30 movable between a protection position where the needle tube 66 is covered and an exposure position where it is exposed, a second coil spring 11 for energizing the cover member 30, and a first coil spring 12 for energizing the operation part 20 to the tip direction with respect to the structure 40. When F0 represents a needle tube discharge resistance for discharging the liquid in the syringe 60 from the needle tube 66, F represents energizing force that is applied by an elastic member including energizing force F1 of the first coil spring 12, and F3 represents dynamic friction force between the operation part 20 and the structure 40, an inequality expression of F>F0+F3 is satisfied, and a liquid administration speed from the needle tube 66 is 1/180 or higher and 1/20 or smaller (mL/sec).COPYRIGHT: (C)2016,JPO&INPIT【課題】投与速度を任意に調節可能であるとともに、使用者への負担を低減できる液体投与具を提供する。【解決手段】液体投与具10であって、操作部20と、シリンジ60および針管66を備え、操作部20に対して移動可能である構造体40と、針管66を覆う保護位置および露出させる露出位置の間を移動可能なカバー部材30と、カバー部材30を付勢する第2コイルバネ11と、操作部20を構造体40に対して先端方向へ付勢する第1コイルバネ12と、を有し、シリンジ60内の液体を針管66から吐出させるための針管排出抵抗をF0、第1コイルバネ12の付勢力F1を含む弾性部材により作用する付勢力をF、操作部20と構造体40との間の動摩擦力をF3としたとき、F>F0+F3を満たし、かつ、針管66からの液体の投与速度が1/180(mL/秒)以上であって1/20(mL/秒)以下である。【選択図】図2
