PROBLEM TO BE SOLVED: To remarkably improve usability.SOLUTION: This liquid medicine administration device 1 detects the state of a flow passage based on the temperature changes of an upstream temperature detection signal SU and a downstream temperature detection signal SL in each pushing operation of a piston 11, and when having detected that there is a possibility that the flow passage is blocked, continues the next pushing operation of the piston 11 when, in the previous pushing operation of the piston 11, the inside of a detection tube 13B in a position where a heating temperature detector 17 is provided is changed from the state of being filled with a liquid medicine MS to the state that air bubbles AR are present. Thereby, the liquid medicine administration device 1 can continue the administration of the liquid medicine without erroneously deciding the state that the air bubbles are mixed in the flow passage as the state that the flow passage is blocked. Thus, the liquid medicine administration device 1 can remarkably improve the usability.COPYRIGHT: (C)2013,JPO&INPIT【課題】一段と使い勝手を向上させる。【解決手段】薬液投与装置1は、ピストン11の押込動作の度に、上流温度検出信号SU及び下流温度検出信号SLの温度変化に基づき流路の状態を検知し、流路が閉塞している可能性があると検知した場合、ピストン11の前回の押込動作において、加熱温度検出子17が設けられた位置における検出管13B内が薬液MSで満たされた状態から気泡ARが存在する状態に変化したとき、ピストン11の次回の押込動作を継続させる。これにより薬液投与装置1は、流路に気泡が混入した状態を、流路が閉塞した状態と誤判定することなく、薬液投与を継続することができる。かくして薬液投与装置1は、一段と使い勝手を向上し得る。【選択図】図11
