Pressure sensor, pressure fluctuation detector and pulse detector using the pressure sensor

Abstract

The present invention has as its objective the presentation of a compact and simple pressure sensor having the ability to measure pulses, the pressure sensor 10 being composed of pressure sensing elements S.sub.1 -S.sub.4 and elastic rubber body 1. The measurement positions Q.sub.1 -Q.sub.4 of the pressure sensing elements S.sub.1 -S.sub.4 are on the bottom surface L of the convex-shaped elastic rubber body 1, at the same distance a from the origin of the x and y axes. If the elastic rubber body 1 is pressed in the vicinity of an artery, blood current changes in said artery, that is, vibrations from the artery occur on the exposed surface of the elastic rubber body 1, these vibrations propagate through the elastic rubber body 1 as elastic waves, and are measured as pressure waves by the pressure sensing elements S.sub.1 -S.sub.4. Their magnitudes decrease as the inverse square of the propagation distance of the elastic waves through the elastic rubber body 1, and the coordinates of the projection of the pressure wave generation point on the bottom surface L are calculated from the voltages V.sub.1 -V.sub.4 of the pressure sensing elements S.sub.1 -S.sub.4 and the distances from the pressure vibration generation point to the measurement positions Q.sub.1 -Q.sub.4. By determining these coordinates for each passage of a set time interval, the pulse front propagation speed and the artery position are able to be determined.

Dependencies are inferred from the claim text.