US 12,446,786 B2
Pulse wave transit time measurement device and living body state estimation device
Toru Shimuta, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on May 15, 2018, as Appl. No. 15/979,578.
Application 15/979,578 is a continuation of application No. PCT/JP2016/080796, filed on Oct. 18, 2016.
Claims priority of application No. 2015-225209 (JP), filed on Nov. 17, 2015.
Prior Publication US 2018/0263518 A1, Sep. 20, 2018
This patent is subject to a terminal disclaimer.
Int. Cl. A61B 5/0225 (2006.01); A61B 5/00 (2006.01); A61B 5/021 (2006.01); A61B 5/024 (2006.01); A61B 5/11 (2006.01); A61B 5/25 (2021.01); A61B 5/332 (2021.01)
CPC A61B 5/02255 (2013.01) [A61B 5/02108 (2013.01); A61B 5/02125 (2013.01); A61B 5/02416 (2013.01); A61B 5/1116 (2013.01); A61B 5/25 (2021.01); A61B 5/332 (2021.01); A61B 5/6822 (2013.01); A61B 5/6831 (2013.01); A61B 5/7264 (2013.01); A61B 5/4806 (2013.01); A61B 5/7225 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A pulse wave transit time measurement device comprising:
an electrocardiographic electrode that detects an electrocardiographic signal;
a pulse wave sensor that detects a pulse wave signal;
a signal processor that calculates a pulse wave transit time based on a peak time difference between the electrocardiographic signal and the pulse wave signal;
a posture detector that detects a posture of a user when the pulse wave transit time is calculated by the signal processor; and
a communication module that is in communication with the signal processor; wherein
the signal processor classifies time serial data of the calculated pulse wave transit time for each posture, based on the posture detected by the posture detector, including a supine position, a left lateral decubitus position, a right lateral decubitus position, and a prone position;
the signal processor determines fluctuations in the pulse wave transit time based on the time serial data of the pulse wave transit time having been classified for each posture by the signal processor, including fluctuations in the time serial data of the pulse wave transit time coinciding with changes of the posture of the user during measurement of the pulse wave transit time;
the communication module transmits in real time the determined fluctuations to an external device;
the signal processor sets a reference posture from among the classified postures, and corrects, in conformity with the reference posture, the time serial data of the pulse wave transit time having been classified into the posture different from the reference posture, the time serial data of the pulse wave transit time is corrected such that the fluctuations in the time serial data of the pulse wave transit time coinciding with the changes of the posture of the user are excluded; and
when determining the fluctuations, the signal processor determines the fluctuations in the pulse wave transit time based on both the time serial data of the pulse wave transit time in the reference posture and the time serial data of the pulse wave transit time having being corrected.