| 摘要 |
<p>PURPOSE:To obtain a pulse sound detector for blood pressure measurement for permitting the blood measurement more surely with high precidion by providing a band-path filter for allowing only the low regional audio frequency component which has the nearly lower limit value of the frequency region of the Korotkoff sound among the pulse sound signals as upper limit to pass, CONSTITUTION:A microphone 30 is installed on a cuff 10. The microphone 30 constitutes a pulse sound sensor, and positioned on one edge part side in the width direction of the cuff 10 positioned on the distal side of an artery in an upper arm part 11, and detects the pulse sound which is generated in synchronization with the heart-beat supplied from the artery and outputs the pulse sound signal SO representing the pulse sound into a band-path filter 32 through an amplifier. Only the low regional audio frequency components in 16-30Hz among the pulse sound signals SO outputted from the microphone 30 pass through the band-pass filter 32, and the blood pressure value is determined on the basis of the variation of the magnitude of the pulse sound signal SO' consisting of the low regional audio frequency components according to the variation of the carf pressure. Since, in this case, the pulse sound signal SO' is hardly given with the influence of the difference of an inspected patient and the rubbing, tapping, swing, etc., of the cuff 10, the blood pressure measurement can be carried out more surely with high precision.</p> |
