Method of adjusting pulse wave measurement device, pulse wave measurement system, and pulse wave measurement device

Patent metadata

Field	Value
Publication number	US-2025344960-A1
Application number	US-202318871274-A
Country	US
Kind code	A1
Filing date	Jun 30, 2023
Priority date	Jun 30, 2022
Publication date	Nov 13, 2025
Grant date	—

Abstract

The present invention is a method of adjusting a pulse wave measurement device attachable to a user's wrist. The pulse wave measurement device includes: a pulse wave sensor including a strain gauge and configured to acquire pulse wave by measuring radial artery pulse; pressing part for pressing the pulse wave sensor to the radial artery; and output part for outputting a measured value of the pulse wave sensor as digital signal. The adjusting method includes: acquiring pulse wave using pulse wave sensor when the pulse wave measurement device is attached to user's wrist, and outputting measured value thus acquired, as a digital signal; comparing voltage level of the digital signal with a range previously set with respect to maximum voltage level of output part; and adjusting or instructing pressing force on pulse wave sensor in a case where voltage level of the digital signal is outside the previously set range.

First claim

1 . A method of adjusting a pulse wave measurement device attachable to a wrist of a user, wherein the pulse wave measurement device includes:
a pulse wave sensor including a strain gauge and configured to acquire a pulse wave by measuring a pulse of a radial artery; a pressing part configured to press the pulse wave sensor to the radial artery; and an output part configured to output a measured value of the pulse wave sensor as a digital signal, the method, comprising, acquiring a pulse wave using the pulse wave sensor when the pulse wave measurement device is attached to a wrist of a user, and outputting a measured value thus acquired, as a digital signal; comparing a voltage level of the digital signal with a range that is previously set with respect to a maximum voltage level of the output part; and adjusting or instructing a pressing force on the pulse wave sensor, in a case where the voltage level of the digital signal is outside the range that is previously set.

2 . The method of adjusting the pulse wave measurement device according to claim 1 ,
wherein the range of the voltage level that is previously set and with which comparison is made in the comparing is equal to or higher than 35% of a maximum output level of the output part.

3 . The method of adjusting the pulse wave measurement device according to claim 1 ,
wherein an output level of the digital signal that is subjected to comparison in the comparing is an average voltage of the digital signal for a desirable period.

4 . The method of adjusting the pulse wave measurement device according to claim 1 , comprising:
performing 0-point correction of the digital signal acquired by the pulse wave sensor as an initial adjustment, before the comparing, when the pulse wave measurement device is attached to the wrist of the user for a first time.

5 . A pulse wave measurement system, comprising:
a pulse wave measurement device attachable to a wrist of a user; and an information processing device capable of communicating with the pulse wave measurement device, wherein the pulse wave measurement device includes:
a pulse wave sensor including a strain gauge and configured to acquire a pulse wave of a radial artery when the pulse wave measurement device is attached to the wrist of the user;
an output part configured to output a measured value of the pulse wave sensor as a digital signal;
a pressing part configured to press the pulse wave sensor to the radial artery; and
an adjusting member configured to adjust a pressing force on the pulse wave sensor, and
the information processing device includes:
a comparison part configured to compare a voltage level of the digital signal with a range that is previously set with respect to a maximum voltage level of the output part; and
an adjustment instruction part configured to instruct adjustment of the pressing force on the pulse wave sensor in a case where the voltage level of the digital signal is outside the range that is previously set.

6 . The pulse wave measurement system according to claim 5 ,
wherein the pulse wave measurement device includes a belt for attachment, the belt being attached to the wrist of the user and being wound outside the pulse wave sensor, the pulse wave sensor includes a strain generating body on which the strain gauge is positioned and that is brought into contact with the wrist of the user, the pressing part is a sensor fastener configured to hold a side of the pulse wave sensor that is opposite to the strain generating body, and the adjusting member is the belt, and is capable of adjusting a biasing force of the pressing part by adjusting a belt length of the belt.

7 . The pulse wave measurement system according to claim 5 ,
wherein the pulse wave sensor includes a strain generating body on which the strain gauge is positioned and that is brought into contact with the wrist of the user, the pressing part is a sensor fastener configured to hold a side of the pulse wave sensor that is opposite to the strain generating body, and the adjusting member is a biasing force adjusting mechanism configured to be brought into contact with a side of the sensor fastener that is opposite to the pulse wave sensor and bias the sensor fastener toward the wrist of the user.

8 . The pulse wave measurement system according to claim 5 ,
wherein the pulse wave sensor of the pulse wave measurement device outputs an analog signal, and the output part includes an amplification circuit and an A/D converter.

9 . The pulse wave measurement system according to claim 5 ,
wherein the information processing device calculates a second derivative of the digital signal that is a measured value of the pulse wave after the pressing force is adjusted, to calculate an acceleration pulse wave.

10 . The pulse wave measurement system according to claim 5 ,
wherein the pulse wave sensor includes a strain generating body to which the strain gauge is attached, and the pulse wave sensor is configured to detect the pulse wave based on a change in a resistance value of the strain gauge caused by deformation of the strain generating body.

11 . The pulse wave measurement system according to claim 10 ,
wherein the strain gauge includes a strain gauge including a resistor made of a film containing Cr, CrN, and Cr 2 N.

12 . The pulse wave measurement system according to claim 5 ,
wherein the pulse wave measurement device further includes a position detector configured to detect a position of the pulse wave sensor with respect to the radial artery.

13 . A pulse wave measurement device attachable to a wrist of a user, the pulse wave measurement device comprising:
a pulse wave sensor including a strain gauge and configured to acquire a pulse wave of a radial artery when the pulse wave measurement device is attached to a wrist of a user; an output part configured to output a measured value of the pulse wave sensor as a digital signal; a comparison part configured to compare a voltage level of the digital signal with a range that is previously set with respect to a maximum voltage level of the output part; a pressing part configured to press the pulse wave sensor to the radial artery; and an adjusting member configured to adjust a pressing force on the pulse wave sensor in a case where the voltage level of the digital signal is outside the range that is previously set.

Assignees

• Minebea Mitsumi Inc

Inventors

• Harada Koshi
• Oka Hiroyuki

Classifications

• A61B2562/0261

  Strain gauges · CPC title

• A61B2562/0219

  Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches · CPC title

• A61B5/6843

  Monitoring or controlling sensor contact pressure · CPC title

• A61B5/681

  Wristwatch-type devices · CPC title

• A61B2560/0223

  of calibration, e.g. protocols for calibrating sensors · CPC title