A pump section (13) for sending liquid medicine in the reservoir (11) for administration to the living body, a flow rate detection section (20) for detecting the flow rate of the liquid solution generated by the pump section (13) And a driving section (40) for controlling the driving state of the pump section (13) based on the detected pressure. The flow rate detection unit (20) includes a heater element (23) disposed in a conduit (21) for sending a chemical liquid, a first heater element (23) arranged in a conduit (21) on the upstream side of the heat generating element , A second temperature detecting element (24) arranged in a conduit (21) on the downstream side of the heat generating element (23), a first temperature detecting element (22) and a second temperature detecting element , And a calculation processing unit (30) for calculating the flow rate in the pipe line (21) based on the detected temperature difference of the pipe (21).リザーバ(11)内の薬液を送液させて生体に投与させるポンプ部(13)と、ポンプ部(13)により生じた送液の流量を検出する流量検出部(20)と、検出した流量に基づいてポンプ部(13)の駆動状態を制御する駆動部(40)とを備える。流量検出部(20)は、薬液を送液させる管路(21)に配置された発熱素子(23)と、発熱素子(23)よりも上流側の管路(21)に配置された第1の温度検出素子(22)と、発熱素子(23)よりも下流側の管路(21)に配置された第2の温度検出素子(24)と、第1及び第2の温度検出素子(22,24)の検出温度差に基づいて、管路(21)内の流量を算出する演算処理部(30)とを備える。
