| 摘要 |
<p>In an electromagnetic blood flowmeter, the blood flow is excited by an alternating rectangular magnetic field with a non-excitation period between each excitation period and the blood flow signal is produced by subtracting the sampled output signal for the non-excitation period from one for the excitation period directly before or after said non-excitation period, wherein both sampling points of the excitation and non-excitation periods are determined possibly close to each other so that ECG signals are effectively eliminated without hightening the exciting frequency. The transformer component also superposed on the blood flow signal is extracted by subtracting the blood flow signal with no transformer component obtained by the known method from said blood flow signal with no ECG signal and averaging the subtracted signal. Thus, pure blood flow signal is also produced by subtracting the extracted transformer component from said blood flow signal with no ECG signal.</p> |
