PROBLEM TO BE SOLVED: To highly accurately measure a blood pressure without enlarging an electronic sphygmomanometer.SOLUTION: A constant-volume control section 104 servocontrols for every beat of the pulse wave while updating a servo gain such that a difference between the arterial volume, which is indicated by the arterial volume signal detected by an arterial volume detection circuit 74, and a control target value of the servo control becomes less than a control deviation where a rate of arterial volume change relative to a cuff pressure change can be regarded as constant. As the control deviation is the difference between the arterial volume indicated by the arterial volume signal and the control target value, a blood pressure determination section 105 corrects a cuff pressure, which is sequentially detected in the period of the servocontrol, using the control deviation and the rate of the change, which can be regarded as constant, and determines it as a blood pressure.COPYRIGHT: (C)2012,JPO&INPIT【課題】装置の大型化を招来することなく、精度良く血圧を測定する。【解決手段】脈波一拍毎に、容積一定制御部104は、動脈容積検出回路74が検出する動脈容積信号が指す動脈容積とサーボ制御の制御目標値との差分がカフ圧変化に対する動脈容積の変化率が一定と見なせる制御偏差未満となるようにサーボゲインを更新しながらサーボ制御する。制御偏差は、動脈容積信号が示す動脈容積と、制御目標値との差であるから、血圧決定部105は、サーボ制御する期間において逐次検出されるカフ圧を、制御偏差および一定と見なせる変化率を用いて補正することにより、血圧として決定する。【選択図】図2
