PROBLEM TO BE SOLVED: To provide a liquid medicine administration device capable of preventing increase of inner pressure of a storage member above a certain value in administration of liquid medicine.SOLUTION: A liquid medicine administration device 100 comprises: a storage member 20 including a storage space 21 for storing a liquid medicine； a needle member 10 having a hollow needle tube in communication wich the storage space； and an extrusion member 30 for extruding the liquid medicine in the storage space into the needle tube based on an operation of the user. The extrusion member comprises: a switching member 50 to be operated by the user； a plunger 40 which operates in coordination with movement of the switching member； and coupling parts 41, 53 coupling the plunger and the switching member. When driving force on the switching member generated by an operation of the user exceeds a certain value, coupling of the switching member and the plunger by the coupling parts is released.SELECTED DRAWING: Figure 3COPYRIGHT: (C)2020,JPO&INPIT【課題】薬剤の投与時に収容部材の内圧が一定値以上、上昇することを防止する薬液投与装置を提供する。【解決手段】本発明に係る薬液投与装置１００は、薬液が充填される収容空間２１を有する収容部材２０と、収容空間に連通する中空な針管を有する針部材１０と、使用者の操作に基づいて、収容空間内の薬液を前記針管に押し出す押出部材３０と、を備え、押出部材は、使用者が操作する切替部材５０と、切替部材の動きに連動する押し子４０と、切替部材と押し子を連結する連結部４１、５３と、を有し、使用者の操作によって発生する切替部材への駆動力が一定値を超えた際に、連結部による切替部材と押し子の連結が解除される。【選択図】図３
