JPH0131367B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an arterial wave detection device, and in particular to a technique for accurately detecting arterial waves regardless of variations in the mounting or holding posture.

BACKGROUND ART The waveform of an arterial wave signal, which is a signal electrically extracted from an arterial wave generated by the heartbeat and propagated through the arteries, contains various cardiovascular information. By analyzing this, various medical information such as the state of cardiac motion and disease states of blood vessels can be obtained. Various detection devices for extracting such arterial wave signals have been proposed. For example, an arterial wave detection device is pressed against the neck of a living body by a worker, or as described in Japanese Patent Application Laid-open No. 51-41285,
There is an arterial wave detection device in which a band to which an arterial wave sensor is attached is wrapped around a part of a living body.

Problems to be Solved by the Invention By the way, in order to accurately detect arterial waves, it is necessary to ensure that the pressing member of the arterial wave sensor is accurately positioned on or very close to the artery of the living body, and that the pressing direction of the sensor is aligned with the body's artery. It was necessary to attach the holding member or to hold it by hand so that it was approximately perpendicular to the skin surface, but in the conventional arterial wave detection device, the holding member was held by a holding member such as a band or The direction in which the arterial wave sensor is pressed against the subject's neck while being held by a worker is determined uniquely from its external shape. It was difficult to hold it, and the arterial waves could not be detected accurately due to variations in the pressing direction.

Means for Solving the Problems The present invention has been made against the background of the above-mentioned circumstances, and its gist is to detect arterial waves generated from arteries under the epidermis when pressed against the epidermis of a subject. An arterial wave detection device for detecting arterial waves, comprising: (a) a sensor housing; and a pressing member provided on the sensor housing in a state of protruding from the sensor housing by a predetermined amount and having a pressing plane at its tip;
(b) a sensor unit configured to detect vibrations transmitted through the pressing member and output a pulse wave signal; (c) a main housing that accommodates the unit with a predetermined distance so as to be able to swing in a plane perpendicular to the artery; and (c) a main housing provided within the main housing to bias the sensor unit. Accordingly, the sensor unit includes biasing means for causing a portion of the sensor unit to protrude from the opening of the main housing in a swingable state.

Operation and Effects of the Invention With this structure, a pressing plane is formed at the tip of the pressing member that protrudes from the sensor housing by a predetermined amount, and the sensor unit is movable in the pressing direction, and the sensor unit is moved against the artery. The main housing is housed within the main housing with a predetermined distance so that it can swing in a plane at right angles to the body.When the main housing is pressed in the direction toward the skin of the living body, the main housing Regardless of the variation in posture, the sensor unit is kept in a posture such that its pressing direction is approximately perpendicular to the skin surface of the living body. Therefore, even if the posture of the main housing varies due to being held by a holding member such as a band or by an operator and being pressed against the subject's neck, the sensor unit will be able to move in the direction of the pressure in the living body. The arterial waves can be detected accurately by being held in a position substantially perpendicular to the skin surface of the patient.

EXAMPLE Hereinafter, in order to clarify the present invention more specifically, one example thereof will be described in detail based on the drawings.

First, FIGS. 1 and 2 are diagrams showing a partially cutaway front view and a plan view of a carotid artery wave detection device according to the present invention. In these figures, 2 is a main housing having a longitudinal box shape. The opening is pressed against the neck of the subject during carotid wave detection.

On the other hand, 4 is a sensor unit each having a function of detecting a carotid artery wave, and the longitudinal direction thereof is parallel to the width direction at right angles to the longitudinal direction of the main housing 2, and the sensor unit 4 is arranged inside the main housing 2. A plurality (six in this embodiment) are housed along the longitudinal direction at predetermined intervals, for example, at intervals of 8 mm.

Each sensor unit 4 is, for example,
As is clear from the figure, a pressing member 10 and an elastic member 12 are housed in a hollow sensor housing in which an upper housing 6 and a lower housing 8 are integrally assembled. The pressing member 10 has a pressing part 14 having a longitudinal shape with a pressing plane formed at the upper end in the center thereof, and a pair of legs 16 extending downward at both longitudinal ends thereof.
The pressing part 14 is housed in the sensor housing with its tip protruding from an opening 18 formed in the upper surface (pressing surface) of the housing 6. On the other hand, the elastic member 12 is made of an elastic metal plate such as a thin stainless steel plate, and has a structure in which a longitudinal rectangular elastic deformation part 20 and an acting part 20 on the outside of the periphery are connected at the center in the longitudinal direction. A pair of protrusions 24 are formed on the lower housing 8 at both longitudinal ends of the elastic deformation section 20 to protrude toward the inside of the sensor housing, and at both longitudinal ends of the action section 22, the pressing member 10 is They are respectively fixed to the lower surfaces of the legs 16 and housed within the sensor housing.

That is, the pressing member 10 is fixed to the sensor housing via the elastic member 12, and thereby the pressing member 10 is fixed to the sensor housing in the vertical direction and
In other words, it can move in a direction parallel to the pressing direction perpendicular to the pressing surface of the housing 6. Note that the movement of the pressing member 10 in the direction parallel to the pressing direction is limited to its upper limit by the shoulder portions 25 on both longitudinal sides of the pressing portion 14 of the pressing member 10 coming into contact with the peripheral edge of the opening 18 of the upper housing 6. but,
In addition, the lower limits of the leg portions 16 of the pressing member 10 come into contact with the lower housing 8, thereby limiting the respective lower limits. When the pressing member 10 is between its upper limit position and lower limit position, the pressing member 10
With the acting portion 22 of the elastic member 12 constantly pressed and bent toward the lower housing 8 side, so that the pressing portion 14 of the elastic member 12 is urged in the direction of protruding from the opening 18 of the housing 6, that is, in the pressing direction, Pressing member 1
0 is attached to the action part 22.

Therefore, in this embodiment, the elastic member 12 is used as the urging means, and the pressing portion 1 of the pressing member 10 is pushed by the elastic force of the elastic member 12 as the urging means.
4 is the housing 6 at its upper limit movement position.
It is adapted to protrude a predetermined length from the opening 18 of. In this embodiment, the length of the projection of the pressing member 14 at this upper limit movement position is equal to the allowable movement distance between the upper and lower limit positions of the pressing member 10 in the pressing direction.

When the sensor unit 4 detects a carotid artery wave, the pressing part 14 of the pressing member 10 is pressed against the neck skin surface with an appropriate pressure, and the carotid artery is transmitted from the carotid artery to the pressing part 14 of the pressing member 10. The undulating vibrations are transmitted to the elastic member 1 through the legs 16.
The magnitude of the elastic deformation caused by the carotid artery wave induced in the elastic deformation part 20 is transmitted to the action part 22 of the elastic deformation part 2, and further transmitted from the action part 22 to the elastic deformation part 20, and the magnitude of the elastic deformation caused by the carotid artery wave induced in the elastic deformation part 20 is It is detected by a strain gauge 26 attached to the lower or upper surface and extracted as an electrical carotid artery wave signal.

At the center of the lower surface of each lower housing 8 of each sensor unit 4 as described above, there is a protrusion 27 directed downward.
is formed, and on the other hand, a protrusion 27 of each sensor unit 4 at the bottom of the cavity of the main housing 2 is formed.
A protrusion 28 is formed at a position corresponding to the opening of the main housing 2. Compression coil springs 30 as pressing means are disposed between the opposing protrusions 27 and 28, respectively, and each sensor unit 4 is moved in the direction in which it independently protrudes from the opening of the main housing 2, that is, in the main housing 2. The housing 2 is biased in the pressing direction.
The movement of each sensor unit 4 in the pressing direction of the main housing 2 is performed by an engagement portion 32 formed to protrude in the longitudinal direction at the lower part of the longitudinal side of each sensor housing and an opening of the main housing 2 in the longitudinal direction. The sensor unit 4 is prevented from moving in the pressing direction by engagement with a flange portion 34 formed to protrude inwardly on a side parallel to the . It is adapted to protrude from the opening of the main housing 2 by a predetermined distance.

When the carotid artery wave detection device as described above is not in use, each sensor unit 4 is pressed to a movement blocking position in the pressing direction, as shown in FIG. Although the pressing member 10 is in a state where it is biased to its upper limit movement position, when the main housing 2 is pressed against the area considered to be above the carotid artery in the neck of the subject when detecting the carotid artery wave, each sensor unit The pressing part 14 of the pressing member 10 of No. 4 is pressed against the cervical skin surface and receives the reaction force, and as a result, the pressing member 10 moves from the upper limit movement position and is released from the constraint from the sensor housing, causing a carotid artery wave. At the same time, the sensor unit 4 itself moves from the movement blocking position in the pressing direction and is released from the restraint from the main housing 2, and swings relative to the main housing 2 around the supported position by the compression coil spring 30 ( The pressing member 10 is pressed perpendicularly to the neck skin surface. A sensor unit is provided in the cavity of the main housing 2 with a predetermined gap so that it can swing in a plane perpendicular to the longitudinal direction of the main housing 2, in other words, in a plane perpendicular to the artery. 4 is accommodated.
The state in which the carotid artery wave can be detected and the state in which the sensor unit 4 can swing are maintained until the pressing member 10 reaches the lower limit movement position, as shown in FIG. 3B. . An example of the swinging state of the sensor unit 4 is shown in FIG. 3C.

In this embodiment, while the pressing member 10 is at the upper limit movement position and the lower limit movement position, the pressing member 1
The elastic force of the elastic member 12, the elastic force of the compression coil spring 30, and the pressing member are adjusted such that the force with which the pressing portion 14 of 0 presses the cervical skin surface is within an appropriate size range for detecting carotid artery waves. 10 pressing parts 14
The length of the sensor unit 4 itself protruding from the opening 18 of the upper housing 6, the length of the sensor unit 4 itself protruding from the opening of the main housing 2, etc. are set respectively.

According to this embodiment described above, the pressing member 10
If the main housing 2 is pressed above the carotid artery in the neck so that Even if the pressing members 10 of each sensor unit 4 are curved or uneven to some extent, each pressing member 10 of each sensor unit 4 will be pressed perpendicularly to the cervical skin surface, and any one of the sensor units 4 will be pressed against the carotid artery. It will be pressed directly above or very close to it, and the carotid artery wave will be accurately detected by any one of the sensor units 4.

In the above embodiment, the sensor unit 4 has a structure that allows easy setting of an appropriate pressing force on the neck, but it is also possible to use a sensor unit with a structure that does not have such an advantage. Therefore, a sensor other than the strain gauge 26 can be used as the sensor itself.

Further, in the above embodiment, the compression coil spring 30 is used as the pressing means, and its structure is extremely simple, but it is also possible to use other elastic materials such as rubber, and furthermore, each Instead of pressing the sensor units 4 with separate pressing means, it is also possible to store a liquid such as water in one bag and use the pressure of the liquid in the bag.

Furthermore, in the embodiment, the sensor unit 4
Although the spacing is 8 mm, it is not limited to this. For example, if the spacing is 15 mm or less, the sensor unit 4 will almost certainly obtain a carotid artery wave signal free from distortion caused by displacement of the pressing position. Even if the interval is longer than that, similar carotid artery wave signals can be obtained with extremely high probability.

In addition, the number of sensor units 4 is not limited to the above embodiment and can be changed as necessary, and the shape and position of the sensor units or the shape of the housing associated therewith can also be changed as necessary. Needless to say, you can get it.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view showing an example of a carotid wave detection device according to the present invention, and FIG. 2 is a plan view thereof. 3A to 3C are cross-sectional views of FIG. 2 showing various aspects for explaining the operation of the device shown in FIG. 1, and FIG. 4 is a sensor unit used in the device shown in FIG. 1. FIG. 2 is an exploded view with screws omitted. 2: Main housing, 4: Sensor unit, 6:
Upper housing (sensor housing), 8: Lower housing (sensor housing), 10: Pressing member, 12: Elastic member (biasing means), 18: Opening,
30: Compression coil spring (pressing means).

Claims (1)

[Scope of Claims] 1. An arterial wave detection device for detecting arterial waves generated from an artery under the epidermis when pressed against the epidermis of a subject, comprising: a sensor housing; and a predetermined amount protruding from the sensor housing. a sensor unit that is provided in the sensor housing in a state where the sensor unit is in a state of being fixed and has a pressing plane at its tip, and that detects vibrations transmitted through the pressing member and outputs a pulse wave signal; A main body is formed with a chamber and accommodates the sensor unit with a predetermined distance so that the sensor unit can be moved in the direction in which the sensor unit is pressed and can swing in a plane perpendicular to the artery. The main housing includes a housing, and a biasing means provided in the main housing that biases the sensor unit to cause the sensor unit to partially protrude from the opening of the main housing in a swingable state. An arterial wave detection device characterized by.