JPH08103419A - Sensor and device for detecting pulse wave - Google Patents

Abstract

PURPOSE: To accurately perform the measurement of pulse waves by accurately transmitting the displacement quantity of the skin fluctuating corresponding to the amplitude of the artery to the center part of a diaphragm by an elastic member and selecting the elastic member suitable for a person to be measured by easily exchanging only the elastic member in a sensor main body. CONSTITUTION: This device consists of the elastic member 1 coming in contact with the skin and which captures the displacement quantity of the skin fluctuating corresponding to the amplitude of the artery, the diaphragm 2 which receives the displacement quantity, an exchange member 3 adhered on the diaphragm 2 and which converts the displacement quantity to an electrical signal, and a holding frame 4 which holds the outer periphery of the diaphragm 2, and a protrusive part 8 is formed on the elastic member 1. Also, the elastic member 1 can easily be fixed so as to be exchanged in the sensor main body by the chamfer recessed step part 5 of the holding frame 4, the chamfer projecting step part 6 of the elastic member 1, or the chamfer projecting step part 13 of another member.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a pulse wave detecting sensor for detecting a pulse wave from a displacement amount of skin which varies according to the amplitude of an artery. Among them, in particular, the present invention relates to a pulse wave detection sensor and a pulse wave detection device using a conversion member that changes a displacement amount into an electrical signal as a displacement amount detection sensor. FIG. 12 shows a cross-sectional view of a pulse wave detection sensor which conventionally utilizes the characteristics of a conversion member 3 for converting a displacement amount into an electric signal. In FIG. 12, the amount of displacement of the skin that contacts the skin and fluctuates according to the amplitude of the artery (hereinafter referred to as pulse pressure)
An elastic member 1 that captures the pulse pressure, a diaphragm 2 that receives the pulse pressure from the elastic member 1, a conversion member 3 that is fixed to the diaphragm 2 and converts the pulse pressure into an electrical signal, and a holding frame that holds the outer periphery of the diaphragm 2. 4 and waterproof packing 9 to prevent water from entering the sensor body
It consists of. In the conventional example, the method of fixing the elastic member 1 and the diaphragm 2 as shown in FIG. 12 is a means such as adhesion, outsert, coating, etc., and it was not possible to replace only the elastic member 1 from the sensor body. Therefore, as shown in FIG. 13, the shape and material of the elastic member 1 are limited to one type. FIG. 3 is an explanatory diagram in which a pulse wave is measured from the vicinity of the radial artery by a pulse wave detection sensor. The elastic member 1 sinks into the skin and applies pressure to the artery to transmit the pulse pressure to the diaphragm 2. Wrist shape, human skin 17 near the radial artery 14, fat, muscles, blood vessels, tendons 1
The mechanism of the living body such as 5 and the bone 16 was different depending on the person, and accurate pulse wave measurement could not be performed. In order to perform accurate pulse wave measurement, the elastic member 1 needs to have a shape and material more suitable for the vicinity of the radial artery of the measurement subject. Therefore, it is necessary to prepare another type of elastic member 1 and easily replace the elastic member 1 suitable for the person to be measured. As in the conventional example of FIG.
When fixing the elastic member 1 to the diaphragm 2 of the pulse wave detection sensor, it is impossible to replace only the elastic member 1 from the sensor body, and the elastic member 1 must be replaced unless the diaphragm 2 is removed from the holding frame 4. There is a problem that you cannot do it. In order to perform more accurate pulse wave measurement, several sensor units had to be prepared for the above reasons. In addition, even if the elastic member 1 needs to be replaced due to damage or wear of the elastic member 1, it is necessary to replace the elastic member 1 together with the diaphragm 1 and the conversion member 3, or the diaphragm 2 must be removed, so that the cost is increased. There was a problem that it took a lot of time for replacement. Therefore, according to the present invention, the elastic member applies an accurate pulse pressure to the central portion of the diaphragm, and moreover, only the elastic member is easily replaced from the sensor main body to select the elastic member suitable for the person to be measured. The purpose is to enable more accurate pulse wave measurement. In order to solve the problems of the prior art, the present invention forms a recessed step portion with a bite on the outer periphery of a holding frame and engages the recessed step portion on the outer periphery of an elastic member. The mating convex stepped portion is molded, or the convex convex stepped portion that engages with the concave stepped portion is adhered or welded to the elastic member by another member and fixed by the biting of the concave stepped portion and the convex stepped portion. It is characterized by The elastic member 1 contacts the skin to capture the pulse pressure, receives the pulse pressure captured by the elastic member 1, and the pulse wave detecting means 19 composed of the diaphragm 2 and the converting member 3 relates to the pulse wave. The output signal is converted into an output signal, and the pulse wave signal conducting means 20 including the conducting member 23 and the lead terminal 24 is conducted to the pulse wave calculating circuit 21 including the pulse wave detecting means 19 and the circuit block 25. The pulse wave calculation circuit 2
The display means 22 including the display element 26 displays the information about the pulse wave output by the display device 1. Embodiments of the present invention will be described below with reference to the drawings. (1) First Example FIG. 1 is a sectional view of a pulse wave detection sensor before the elastic member 1 is attached to the sensor body. In FIG. 1, the elastic member 1
Has a protruding portion 8 formed by molding in the central portion on the side where the diaphragm 2 is present, or another member such as metal or plastic is formed by adhesion, insert, outsert or the like. FIG. 8 is a sectional view of the elastic member 1 in which the protruding portion 27 is formed by another member, and shows an embodiment in which the protruding portion 27 is formed in the central portion of the elastic member 1.
By providing the protruding portion 27, a large pulse pressure can be concentratedly transmitted to the central portion of the diaphragm 2. Further, the elastic member 1 is formed with a protruding stepped portion 6 with a bite which engages with the recessed stepped portion 5 on the outer peripheral portion of the holding frame 4. The vibrating plate 2 receives the pulse pressure from the protruding portions 8 and 27 of the elastic member 1 in a centralized manner,
It becomes easier to bend. Further, when the diaphragm 2 is thin, it is more easily bent. The conversion member 3 is fixed to the diaphragm 2 by adhesion or the like, and converts the pulse pressure into an electric signal. Specific examples thereof include electrostrictive elements represented by piezoelectric elements, semiconductor elements represented by semiconductor pressure sensors, and pressure-sensitive conductive elastic members such as pressure-sensitive rubber. The holding frame 4 holds the outer peripheral portion of the diaphragm 2 by the concave step portion 10 on the inner diameter side of the holding frame, and engages with the outer peripheral convex step portion 6 of the elastic member 1 by the concave step portion 5 on the outer diameter side of the holding frame. , The elastic member 1 is fixed. By providing the holding frame 4 with the recessed stepped portion 5, a sufficient bited portion can be secured without thickening the diaphragm 2, and the elastic member 1 is fixed to the sensor body. By this fixing, only the elastic member 1 could be easily exchanged from the sensor body. FIG. 2 is a sectional view of the pulse wave detection sensor after the elastic member 1 is attached to the sensor body. Waterproof packing 9
Prevents water from entering the sensor body. When the elastic member 1 is set on the sensor body, the waterproof function can be satisfied without the waterproof packing 9. (2) Second Embodiment FIG. 6 is a plan view showing an annular bite-shaped convex step portion 11 on the outer peripheral portion of the elastic member 1 in a direction perpendicular to the diaphragm 1 and an annular bite-shaped concave step portion of the holding frame 4. 12 was provided, and the elastic member 1 was fixed to the sensor body by the biting of the biting convex step portion 11 and the biting concave step portion 12. By this fixing, the elastic member 1 could be replaced easily from the sensor body. Other configurations are the same as those in the first embodiment. (3) Third Embodiment FIG. 7 shows the engagement with the biting concave step 5 of the holding frame 4 by bonding and welding the biting convex step 13 of another member such as metal or plastic to the elastic member 1. Then, the elastic member 1 was fixed to the sensor body. By providing the separate member 13, the fixing strength with the sensor body can be strengthened, and the elastic member 1 can be easily exchanged from the sensor body. Further, the separate member 13 may be engaged with the holding frame 4 while sandwiching the elastic member 1 as a separate component without adhering or welding to the elastic member 1. Other configurations are the same as those in the first embodiment. (4) Fourth Embodiment FIGS. 9, 10 and 11 are sectional views showing an example of the shape of the elastic member 1 of the pulse wave detection sensor of the present invention. FIG. 9 is a cross-sectional view of an example in which the contact surface shape of the elastic member 1 with the skin is an R-shaped protrusion. FIG. 10 is a cross-sectional view of an embodiment in which the contact surface shape of the elastic member 1 with the skin is a planar projection. FIG. 11 is a cross-sectional view of an embodiment in which the elastic member 1 has a recess at the center. As described above, various shapes of the elastic member 1 are conceivable, and the material may be silicone rubber, urethane rubber, or the like, and the shape and material of the elastic member 1 suitable for the measurement subject are prepared. As described above, according to the present invention, the elastic member is provided on the wrist by reducing the contact area with the skin and providing the protrusion when measuring the pulse wave near the radial artery. It can immerse into the skin without causing discomfort, approach the radial artery, and intensively transmit the pulse pressure to the central part of the diaphragm. Further, the elastic member has excellent impact resistance and absorbs a strong impact near the radial artery. Further, the elastic member prevents slippage and enables accurate pulse wave measurement without the pulse wave measurement sensor shifting from the vicinity of the radial artery. As mentioned above, the shape of the wrist and the mechanism of the living body near the radial artery vary from person to person. By making only the elastic member replaceable from the sensor body, an elastic member suitable for the person to be measured can be selected, and accurate pulse wave measurement can be performed regardless of the difference in the living body. Further, with respect to various problems such as breakage and wear of the elastic member, only the elastic member can be easily replaced from the sensor body.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a first embodiment of a pulse wave detection sensor before attaching an elastic member of the present invention to a sensor body. FIG. 2 is a sectional view of the first embodiment of the pulse wave detection sensor after the elastic member of the present invention is attached to the sensor body. FIG. 3 is an explanatory diagram when detecting a pulse wave near the radial artery. FIG. 4 is a functional block diagram showing an example of a typical configuration of the pulse wave detection device of the present invention. FIG. 5 is a component configuration diagram showing a conduction path of a functional block diagram showing an example of a typical configuration of the pulse wave detection device of the present invention. FIG. 6 is a cross-sectional view of the pulse wave detection sensor after the elastic member is attached in the second embodiment of the pulse wave detection device of the present invention. FIG. 7 is a sectional view of a pulse wave measuring sensor after an elastic member is attached in the third embodiment of the pulse wave detecting device of the present invention. FIG. 8 is a sectional view of a first embodiment of an elastic member in which a protrusion is formed by another member of the present invention. FIG. 9 is a sectional view of a fourth embodiment of the elastic member of the present invention. FIG. 10 is a sectional view of a fourth embodiment of the elastic member of the present invention. FIG. 11 is a sectional view of a fourth embodiment of the elastic member of the present invention. FIG. 12 is a cross-sectional view of a conventional pulse wave detection sensor. FIG. 13 is a cross-sectional view of a conventional elastic member. [Description of Reference Signs] 1 elastic member 2 diaphragm 3 conversion member 4 holding frames 5 and 12 holding frame outer diameter side recessed concave step portion 6 and 11 elastic member biting convex step portion 7 diaphragm receiving surface 8 elastic member protruding portion 9 Waterproof packing 10 Recessed frame outer side concave stepped portion 13 Convex stepped portion with bite of metal, plastic, etc. 14 Radial artery 15 Tendon 16 Radius 17 Skin 18 Sensor body 19 Pulse wave detecting means 20 Pulse wave signal conducting means 21 Pulse wave calculating circuit 22 Display means 23 Conductive member 24 Lead terminal 25 Circuit block 26 Display element 27 Projection part of metal, plastic, etc.

Claims (1)

Claim: What is claimed is: 1. An elastic member (1) that comes into contact with the skin and captures a displacement amount of the skin that fluctuates according to the amplitude of an artery, and a vibration that receives the displacement amount through the elastic member (1). Board (2)
A pulse wave measurement including a conversion member (3) that is fixed to the diaphragm (2) and changes the displacement amount into an electrical signal, and a holding frame (4) that holds the outer peripheral portion of the diaphragm (2). The sensor is a sensor, in which a biting concave step (5) is formed on the outer circumference of the holding frame (4), and a biting convex step (5) engaged with the concave step (5) on the outer peripheral part of the elastic member (1). 6) is molded, or a protruding stepped portion (13) with a bite which engages with the recessed stepped portion (5) is adhered or welded to the elastic member (1) by a member different from the elastic member (1). Pulse wave detection sensor. 2. A protrusion (8) is formed at the center of the receiving surface (7) of the elastic member (1) for receiving the vibration plate (2) toward the conversion member (3) or is formed by another member. The pulse wave detection sensor according to claim 1, wherein a protrusion (27) is formed. 3. A pulse wave detecting device comprising the pulse wave detecting sensor according to claim 1 or 2, and calculating and displaying a pulse wave based on an output signal of the pulse wave detecting sensor.