To perform electrocardiographic measurement accurately.SOLUTION: To a differential amplifier 34, a steering electrode 12 of a steering wheel 22 is connected and a sheet electrode 16 is connected through a switching unit 42. The switching unit 42 performs switching between a grounded state in which the sheet electrode 16 is connected to a grounding electrode GND and a non-grounded state in which the sheet electrode is connected to the differential amplifier 34. A control unit 44, when it is determined from a differential signal of the differential amplifier 34 that removal of electricity of an occupant has been completed, switches the sheet electrode 16 from the grounded state to the non-grounded state. Thereby, measurement of an electrocardiographic waveform can be started at appropriate timing after completion of removal of electricity of the occupant.SELECTED DRAWING: Figure 1
【課題】心電計測を高精度にする。【解決手段】差動増幅器34には、ステアリングホイール22のステアリング電極12が接続されていると共に、シート電極16が切替部42を介して接続されており、切替部42は、シート電極16を接地極GNDに接続する接地状態と差動増幅器34に接続する非接地状態とに切替える。制御部44は、差動増幅器34の差動信号から乗員の除電が終了したと判断されると、シート電極16を接地状態から非接地状態に切替える。これにより、乗員の除電が終了した適切なタイミングで心電波形の計測を開始できる。【選択図】図1
ELECTROCARDIOGRAPHIC DETECTOR FOR VEHICLE
車両用心電検出装置
2020-12-10
Patent
Electronic Resource
Japanese