JP2009066042A - Pulse wave measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To unerringly perform shielding against disturbance light during measurement and accurately perform the measurement of the amplitude of a pulse wave. <P>SOLUTION: The pulse wave measuring instrument 1 has a finger insertion portion 3 into which a subject inserts his or her fingertip which is rotatably attached to a body portion 2 rotatable around a shaft 81. Since a LED and a pulse wave sensor are arranged in the finger insertion portion 3, and the pulse sensor outputs a square wave pulse signal in accordance with light reflected in the finger, counting the period of the pulse signal permits a pulse to be detected. When the subject presses his or her fingertip against the inside of the finger insertion portion 3, the load makes the finger insertion portion 3 rotate around the shaft 81, and is applied to the pressure sensor 24. Making the subject himself or herself adjust his or her power so as to put the load within an appropriate range permits an appropriate pulse wave to be obtained. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pulse wave measuring device that measures a pulse wave by inserting a fingertip.

As an apparatus for measuring a pulse wave with a fingertip of a hand, for example, as disclosed in Patent Document 1, an apparatus including a measuring unit including a pair of spring-biased clip pieces is known. In this measurement unit, a light emitting unit is provided on one clip piece, and a light receiving unit is provided on the other clip piece. When the light emitting unit emits light after the fingertip is sandwiched between the pair of clip pieces, the light transmitted through the fingertip is taken into the light receiving unit. An element that generates a current according to the intensity of the received light is used in the light receiving unit. When the analog signal output from the light receiving unit is converted into a digital signal and processed, pulse wave information is obtained.
In addition, as disclosed in Patent Document 2, there is a type in which the measurement unit is mounted between the base of the index finger and the finger joint using a fixing band.
JP 2007-20836 A JP 2004-188224 A

However, in the conventional measurement unit, external light is easily incident on the light receiving unit. If the signal from the external light is superimposed on the pulse wave signal, the measurement accuracy is lowered, which is not preferable.
In addition, when determining the stress state of the subject from the pulse wave, it is necessary to appropriately measure the amplitude of the pulse wave. In this case, it is necessary to measure the pulse wave by applying a substantially constant load to the subject's fingertips, but in conventional measurement units, the load with which the clip pinches the fingertip changes or is fixed due to individual differences in the subject. Because the load changes depending on the winding of the band, the measurement conditions are not stable and it is difficult to improve the measurement accuracy.
The present invention has been made in view of such circumstances, and it is possible to accurately measure the amplitude of a pulse wave by reliably shielding external light during measurement and maintaining a constant load on the finger during measurement. The main purpose is to be able to do well.

The invention according to claim 1 of the present invention that solves the above-described problems is a finger insertion part in which a fingertip of a subject can be inserted and a light emitting element and a light receiving element are arranged toward the abdomen of the fingertip, and insertion of the fingertip A body portion that rotatably supports the finger insertion portion with a near side in the direction as a fulcrum, and the finger insertion portion includes a pressing direction and a fingertip direction when the abdomen of the fingertip is pressed toward the light receiving element. A rotation shaft extends in a direction orthogonal to each of the insertion directions, an elastic member is provided at the bottom so as to protrude in the pressing direction, and the main body includes a pressure sensor with which the elastic member can contact, and the finger insertion portion The pulse wave measuring device is characterized in that an opening having a shape allowing only the finger insertion portion to rotate is formed.
This pulse wave measuring device inserts a fingertip into a finger insertion part while lightly grasping a main body part. When the fingertip is pressed toward the light emitting element and the light receiving element, the finger insertion part rotates around the rotation axis. And since the elastic member provided in the rotation direction presses a pressure sensor, the force which presses a finger | toe is measured. By detecting the load applied to the fingertip, the measurement can be performed with a substantially constant load applied.

According to a second aspect of the present invention, in the pulse wave measuring device according to the first aspect, the finger insertion portion is arranged to be inclined with respect to the main body portion, and the back side in the insertion direction is lower than the front side. It is characterized by that.
When the fingertip is inserted into the finger insertion portion while lightly grasping the main body with this pulse wave measuring device, the finger is in a natural posture due to the inclination of the finger insertion portion.

According to a third aspect of the present invention, in the pulse wave measuring device according to the first aspect, the main body portion displays a magnitude of a detected value of the pressure sensor on a lateral side portion sandwiching the finger insertion portion. Are provided one by one.
In this pulse wave measuring device, the display on the load monitor changes according to the force with which the finger is pressed. If this is confirmed, it can be easily determined whether or not an appropriate measurement condition has been reached. If the load monitor display is inappropriate, adjust the force with which you press your finger.

The invention according to claim 4 is the pulse wave measuring device according to claim 1, wherein an impermeable material is provided on the inner surface of the finger insertion portion.
In this pulse wave measuring device, when there is a possibility that the base material of the finger insertion portion transmits light, the non-transmissive material is arranged so that external light does not reach the finger or the light receiving element.

The invention according to claim 5 is the pulse wave measuring device according to claim 1 or claim 4, wherein the finger insertion portion is provided with a plurality of light emitting elements sandwiching the light receiving element, and the plurality of light emitting elements. The element is characterized in that the distance from the light receiving element is different.
In this pulse wave measuring device, even when there is an individual difference in the subject's finger, any one of the light emitting elements is in a position suitable for measurement.

According to a sixth aspect of the present invention, in the pulse wave measuring device according to the fourth aspect, the finger insertion portion includes a temperature sensor that detects the temperature of the fingertip across the light receiving element, and a pin connected to the ground. It is characterized by.
In this pulse wave measuring device, if the temperature of the fingertip is too low or too high, correct pulse wave data cannot be acquired, and therefore monitoring is performed by a temperature sensor. In addition, the grounding of the fingertip prevents the generation of noise due to fingertip charging.

The invention according to claim 7 is the pulse wave measuring device according to claim 5 or 6, wherein the light receiving element outputs a pulse signal having a different frequency in accordance with the amount of light.
Since this pulse wave measuring device outputs a digital signal, the pulse wave measuring device has a simpler circuit configuration than an analog output type. Moreover, since it is output as a digital signal, it is strong against noise.

The invention according to claim 8 is the pulse wave measuring device according to claim 1, wherein a recess for avoiding the nail is provided on the inner surface of the finger insertion portion on the back side in the insertion direction.
In this pulse wave measuring device, even when the nail is long, the finger does not hit the inner surface of the finger insertion portion, so that the inspection position can be prevented from shifting.

  According to the present invention, pulse wave measurement and amplitude data can be obtained with high accuracy since the subject performs pulse wave measurement in a state where pressure is applied by pressing the fingertip against the light receiving element. Since the position of the finger insertion part against the pressure sensor is prevented by the opening formed in the main body, the force with which the subject presses the fingertip can be detected correctly, and pulse wave data and amplitude data can be acquired stably. it can.

The best mode for carrying out the invention will be described in detail with reference to the drawings.
As shown in FIG. 1 and the block diagram of FIG. 2, the pulse wave measuring device 1 includes a main body portion 2 and a finger insertion portion 3 rotatably attached to the main body portion 2. 2 is wired and connected to an analysis device, for example, a general-purpose personal computer (hereinafter referred to as a personal computer) 4.

As shown in FIG. 2, a sensor substrate 11 is built in the finger insertion portion 3. An LED (light emitting diode) 21 that is a light emitting element, a pulse wave sensor 22 that is a light receiving element, and a temperature sensor 23 are mounted on the sensor substrate 11.
The main body 2 includes a pressure sensor 24, a load monitor 12 that informs the subject of the load, and a signal processing board 13. The signal processing board 13 includes an LED light amount adjustment circuit 32 that is connected to the LED 21 and constitutes a pulse wave detection circuit 31 together with the pulse wave sensor 22, and a temperature sensor signal amplification that is connected to the temperature sensor 23 and constitutes a temperature detection circuit 33. A circuit 34 and a pressure sensor signal amplification circuit 36 constituting a load detection circuit 35 together with the pressure sensor 24 are provided. Further, each circuit 32, 34, 36 and pulse wave sensor 22 are connected, and a microcomputer 37 having a CPU (Central Processing Unit), a memory, and the like, and a USB (Universal) for performing data communication between the microcomputer 37 and the personal computer 4. Serial Bus) includes a communication circuit 38 and a power supply circuit 39 that is connected to an external power source (not shown) through a personal computer 4 connected via USB and that stably supplies power to the microcomputer 37 and circuit elements.

  FIG. 3 shows the configuration of the LED 21, the pulse wave sensor 22, and the LED light amount adjustment circuit 32 that form the pulse wave detection circuit 31. The LED 21 that emits red light having a fundamental wavelength near 650 nm is used. Since red light has a wavelength that easily enters the human body, a clear pulse wave signal can be collected. Further, since red light is visible, it is easy to determine a failure when it is not lit. Although two LED light quantity adjustment circuits 32 are connected in parallel in FIG. 3, the number and arrangement in parallel are not limited to this.

  The LED light amount adjustment circuit 32 is configured such that an ON / OFF signal from the microcomputer 37 is input to the gate of the transistor T1 connected to the high-potential side terminal of the LED 21 and the low-potential side of the pair of LEDs 21. A constant current circuit 41 having an operational amplifier OP1 and a transistor T2 connected to the terminals is provided. In the constant current circuit 41, a signal obtained by converting a PWM (pulse width modulation) signal from the microcomputer 37 into a DC voltage is input to the negative terminal of the operational amplifier OP1, and a constant current command value (PWM signal) The current flowing through the LED 21 can be controlled by arbitrarily changing the (duty). A shunt resistor 42 is inserted between the constant current circuit 41 and GND. By measuring the current flowing through the shunt resistor 42, the basic current value can be determined and the current value can be fed back. In such an LED light quantity adjustment circuit 32, the amount of light irradiation can be varied according to the conditions, so that a pulse wave with optimum sensitivity can be obtained.

  The pulse wave sensor 22 emits light from the LED 21, receives light after passing through the fingertip, and generates a square wave pulse signal. The LFC changes the frequency of the square wave pulse signal according to the brightness of the reflected light. (Light to frequency converter) is used. The square wave pulse signal is input to the edge detection port of the microcomputer 37. If the counter of the microcomputer 37 counts the edges of the square wave pulse signal, a pulse wave can be obtained. The pulse wave sensor 22 is resistant to noise because it converts the amount of light into a variable frequency pulse signal.

FIG. 4 shows a configuration of the temperature detection circuit 33 including the temperature sensor 23 and the temperature sensor signal amplification circuit 34. The temperature sensor 23 is a thermistor. The thermistor that can measure the temperature of the fingertip in the range of 10 to 45 ° C. is selected. In FIG. 4, the thermistor is illustrated as a variable resistor.
The temperature sensor signal amplifying circuit 34 connects the temperature sensor 23 and the resistor R1 in series between an input terminal of a predetermined voltage and GND in order to convert a change in the resistance value of the temperature sensor 23 into a voltage signal. The potential VA is detected. Further, in order to remove noise of the signal of the potential VA, a CR low-pass filter 43 is connected and a differential amplifier circuit 44 is provided. The gain of the differential amplifier circuit 44 is adjusted to be a voltage (for example, 5V or 3V) that can be input to the microcomputer 37 with reference to a preset offset removal voltage.

  The load detection circuit 35 shown in FIG. 2 uses a strain gauge as the pressure sensor 24. The pressure sensor signal amplifying circuit 36 is configured to convert a change in resistance value when the strain gauge is a variable resistance into a voltage signal, and has substantially the same configuration as the temperature sensor signal amplifying circuit 34 described above. Yes. That is, a strain gauge and a resistor are connected in series between an input terminal of a predetermined voltage and GND, a CR low-pass filter is connected to remove signal noise at the connection point, and a voltage that can be input to the microcomputer 37 ( For example, a differential amplifier circuit whose gain is adjusted to be 5 V or 3 V) is provided. By performing pressure detection with the load detection circuit 35, a pulse wave with high accuracy can be obtained.

  Here, since a mechanism that constantly applies an appropriate pressure to the fingertip is difficult to adjust, the pulse wave measuring apparatus 1 employs a structure in which the subject himself presses the finger against the finger insertion portion 3 to apply pressure. For this reason, as shown in FIG.1 and FIG.5, the main-body part 2 has a curved surface which a test subject can grasp lightly in the state which put the fingertip in the finger insertion part 3. FIG. The finger insertion portion 3 is disposed at the approximate center in the left-right direction near the tip of the main body portion 2 corresponding to the position of the fingertip when the main body portion 2 is lightly grasped, and an opening formed in the main body portion 2 A part from 51 is inserted into the main body 2. The height of the finger insertion portion 3 is set so that the lower end of the insertion port 64 is disposed above the opening 51. Furthermore, the finger insertion part 3 is inclined so that the tip side, that is, the back side in the insertion direction indicated by d1 in FIG. 5 is lowered with respect to a horizontal plane parallel to the bottom surface 2A of the main body part 2. A non-slip rubber 52 is attached to the bottom surface 2A so that the main body 2 does not slide and move. The slip stopper may be other than the rubber 52.

Furthermore, as shown in FIG. 6, in the main body 2, one load monitor 12 is disposed on each of the left and right side portions sandwiching the finger insertion portion 3. Each load monitor 12 has a configuration in which three LEDs 55, 56, and 57 are arranged, and can display in three stages according to the magnitude of the pressure with which the subject presses the fingertip. As shown in FIG. 7, the output of the load detection circuit 35 is input to the load determination unit 58 of the microcomputer 37. The load determination unit 58 searches the map 59 and outputs a lighting signal to the LEDs 55 to 57 of the load monitor 12 according to the pressure level.
The map 59 is preset with a lower limit value CL and an upper limit value CU of the optimum load range. When the signal input to the load determination unit 58 is smaller than the lower limit value CL, the LED 55 is turned on and the LEDs 56 and 57 are turned off. When the input signal is greater than or equal to the lower limit value CL and smaller than the upper limit value CU, only the LED 56 is lit. When the input signal is equal to or higher than the upper limit value CU, only the LED 57 is lit. In the optimum load range, only the LED 56 is lit, so that the subject can easily confirm whether or not the pressing state necessary for measurement is in view of the display on the load monitor 12.

  Since the load monitor 12 is provided on the front side portion of the main body 2, the load monitor 12 can be visually confirmed without being hidden by a finger even when the main body 2 is lightly gripped. Since one load monitor 12 is provided for each of the left and right sides, the load monitor 12 can be visually confirmed whether the measurement is performed with the right hand or the left hand. Note that the load determination unit 58 may be configured to search the map 59 by the upper limit value and lower limit value of the resistance value or voltage. When the color of the central LED 56 is different from that of the other two LEDs 55 and 57, it becomes easier to confirm. For example, if the central LED 56 is green and the other two LEDs 55 and 57 are red, it is easy to intuitively understand whether the load is appropriate. Note that the lighting pattern such as lighting only when the load is within the optimum load range and the number of LEDs to be lit can be changed as appropriate.

As shown in FIGS. 1 and 8, the finger insertion portion 3 includes a base portion 61 supported by the main body portion 2 and a case lid portion that is connected to the distal end side of the base portion 61 by a hinge 62 and can be opened upward. 63. When the case lid 63 is closed, an insertion port 64 for inserting a fingertip is formed. The case cover part 63 and the base part 61 are manufactured from resin or the like. A non-transmissive material 65 such as aluminum tape is attached to the inner surfaces of the base portion 61 and the case lid portion 63 so that ambient light does not enter the inside through the base portion 61 and the case lid portion 63. By blocking the light, the disturbance light is blocked, and only the light from the LED 21 is detected to obtain a pulse wave with high accuracy. In addition, if the non-transmissive material 65 is made black, the light shielding property is further enhanced.
As shown in FIGS. 9 and 10, a recess 66 is provided at the tip of the base portion 61. The recess 66 serves as a relief when a woman or the like inserts a finger with a long nail so that the sensing position does not shift because the nail hits the inner surface of the base portion 61 or the inner surface of the case lid portion 63.

  The bottom surface in the base portion 61 is a finger insertion portion bottom surface 67 having a curved surface shape that matches the shape of the fingertip. The finger insertion portion bottom surface 67 is a surface on which the subject presses the abdomen of the fingertip. The bottom surface 67 of the finger insertion portion is provided with three windows 71, 72, 73 in the left-right direction intersecting with the finger insertion direction. Furthermore, two holes 74 and 75 are provided through the central window 72 in the front-rear direction parallel to the finger insertion direction with the window 72 interposed therebetween. The hole 74 on the back side (front side) in the insertion direction is arranged so that the temperature sensor 23 can measure the temperature of the fingertip. A GND pin 76 is inserted into the hole 75 on the near side (rear side) in the insertion direction so as to be in contact with the fingertip. The GND pin 76 prevents noise from being superimposed on the signal of the pulse wave sensor 22 due to the influence of capacitance or the like generated by charging the finger.

A pulse wave sensor 22 is disposed below the central window 72, and one LED 21 is disposed below each of the left and right windows 71 and 73. If the fingertip is inserted together with the central window 72, the temperature sensor 23 and the GND pin 76 arranged in front of and behind the window 72 naturally come into contact with the fingertip, so that temperature measurement and removal of stray capacitance are ensured. Can be done. In this embodiment, a region including the window 72 and the holes 74 and 75 surrounded by a broken line in FIG. 9 is a sensing position Ps where a finger is pressed to detect a pulse wave.
Here, a shield member 78 is fitted in the windows 71 to 73 so that the measurement light can be transmitted but water and foreign matter cannot pass therethrough and the fingertip does not directly touch the LED 21 or the pulse wave sensor 22. As the shield member 78, for example, a sheet made of silicone resin is used. The size of the central window 72 is a minimum size necessary for causing only the reflected light of the LED 21 to enter the pulse wave sensor 22. This is because if the window 72 is too large, ambient light enters from the gap between the finger and the finger insertion portion bottom surface 67 and enters the pulse wave sensor 22.

  Further, as shown in FIG. 11, the distances between the center line of the pulse wave sensor 22 and the centers of the left LED 21 and the left LED 21 are different distances Ll and Lr, respectively. By arranging the two LEDs 21 asymmetrically with respect to the pulse wave sensor 22, even when the shape and thickness of the finger differ depending on the subject, it can be brought into close contact with any one of the shield members 78 in a measurable manner. .

As shown in FIG. 12, one shaft 81 projects in the horizontal direction on the proximal side of each outer surface of the base portion 61 in the left-right direction. The shaft 81 is a rotating shaft of the finger insertion portion 3 and is supported by a bearing portion 82 provided inside the main body portion 2. The horizontal direction is a direction orthogonal to the direction in which the finger is inserted into the finger insertion portion 3 indicated by the arrow d1 in FIG. 5 and the pressing direction of the abdomen of the fingertip indicated by the arrow d2. For this reason, the finger insertion part 3 can rotate the back side of the insertion direction in the direction of the arrow d2 from the shaft 81 as a starting point. The shaft 81 may be a single shaft that penetrates the base portion 61.
A lid member 83 is attached to the bottom, which is the lower outer surface of the base portion 61, and a rubber 84 that is an elastic member is fixed to the bottom of the lid member 83. A pressure sensor 24 is disposed below the rubber 84. The rubber 84 has a cylindrical shape extending in the fingertip pressing direction d2 (rotating direction of the finger insertion portion 3) in accordance with the shape of the pressure sensitive region of the pressure sensor 24. The rubber 84 functions as a mechanical filter when the pressure sensor 24 is pressed, so that a local high pressure is not transmitted to the pressure sensor 24. This allows the averaged finger pressure to be transmitted to the pressure sensor 24.

Next, pulse wave measurement using this pulse wave measuring apparatus 1 will be described.
A subject who performs pulse wave measurement (or stress determination) inserts the forefinger from the insertion port 64 of the finger insertion unit 3 while gently grasping the main body 2 with the right hand or the left hand. At this time, if the case lid 63 is opened and the fingertip is placed while checking the position of the window 72, the positional deviation can be easily prevented. Moreover, it is good to confirm light emission of LED21 when the case cover part 63 is opened, and to confirm that there is no failure.
The temperature sensor 23 contacts the fingertip at the sensing position Ps, detects the temperature, and transmits the result to the personal computer 4. When the temperature of the fingertip is too low, there is a case where the fluctuation of the blood flow is small and the pulse wave cannot be collected correctly, which is not preferable as a measurement condition. Therefore, the personal computer 4 displays an error. Similarly, when the temperature of the fingertip is too high, the personal computer 4 displays an error. By feeding back the temperature measurement result to the display on the personal computer 4, the subject can easily check whether the pulse wave can be detected. Further, even if the fingertip is charged by the GND pin 76, it is dropped to the GND level, and noise superposition is prevented.

  Furthermore, the finger insertion part 3 rotates with respect to the main-body part 2 centering on the shaft 81 by pressing a fingertip with an appropriate force. The rubber 84 on the tip side of the shaft 81 moves downward and is pressed against the pressure sensitive range of the pressure sensor 24. Here, the opening 51 of the main body 2 allows the finger insertion portion 3 to rotate about the shaft 81, but the side surface of the finger insertion portion 3 and the opening 51 move in contact in the left-right direction. To regulate. In this way, by providing the main body 2 with the instruction to turn the finger insertion portion 3 so as to be rotatable, by providing a load direction limiting mechanism that restricts the turning direction by the shape of the finger insertion portion 3 and the shape of the opening 51. As shown in FIG. 13, the load range Rg due to the rubber 84 and the pressure sensitive range Rs of the pressure sensor 24 are not shifted, and the load from the fingertip can be accurately measured. If there is no load direction limiting mechanism including the opening 51, the load range Rg and the pressure sensitive range Rs may be misaligned as indicated by the phantom line, and the load from the fingertip may not be detected correctly.

  The subject confirms the load thus measured with the load monitor 12. If the LED 56 is lit, an appropriate state is reached, and the pulse wave measurement is performed as it is. When the load is inappropriate, for example, when the LED 55 is lit, the pressing force is increased. When the LED 57 is lit, the pressing force is loosened. By performing pressure detection, a pulse wave with high accuracy and an amplitude of the pulse wave can be obtained.

When the pulse wave measurement is started, a current is supplied to the two LEDs 21 of the pulse wave detection circuit 31 by a signal from the microcomputer 37. The microcomputer 37 outputs a constant PWM signal to the LED light amount adjustment circuit 32 in response to a command from the personal computer 4. The PWM signal is converted into an analog DC voltage by a low-pass filter. The DC voltage is input to the positive input terminal of the operational amplifier OP1. The terminal voltage is input to the negative terminal of the operational amplifier OP1 on the opposite side of the shunt resistor 42 from the GND. The operational amplifier OP1 compares the shunt resistance voltage at the negative input terminal with the command DC voltage at the positive input terminal. When the potential at the positive input terminal is large, the output voltage of the operational amplifier OP1 increases. Conversely, when the potential at the negative input terminal is large, the output decreases. As the output of the operational amplifier OP1 increases, the base current of the transistor T2 increases, so the collector current also increases. As a result, the current flowing through the LED 21 and the shunt resistor 42 increases, and the LED 21 becomes brighter. Further, when the potential of the shunt resistor 42, that is, the potential of the negative terminal input of the operational amplifier OP1 becomes larger than the potential of the positive terminal, the output voltage of the operational amplifier OP1 decreases, the base current decreases, and the collector current also decreases. As a result, the current flowing through the LED 21 and the shunt resistor 42 decreases, and the brightness of the LED 21 becomes dark. In this way, the command voltage input to the plus terminal of the operational amplifier OP1 changes according to the DUTY of the PWM signal output from the microcomputer 37, so that the brightness of the LED 21 is arbitrarily adjusted according to the command from the personal computer 4. be able to. Since the amount of light irradiation can be varied according to conditions, a pulse wave with optimum sensitivity can be obtained.
The red light that reaches the blood vessels in the finger is partially absorbed by hemoglobin in the blood and partially reflected. Therefore, the pulse wave appears as a change in the amount of reflected light from the finger. The pulse wave sensor 22 is resistant to noise because it converts the light amount into a frequency variable pulse signal. Furthermore, since this signal is directly input to the port of the microcomputer 37, an analog circuit such as an operational amplifier is not required, and the circuit can be miniaturized. Since the period of the frequency variable type pulse signal is detected by a built-in timer (usually 16 bits) rather than the analog signal is detected by an A / D converter (usually a 10-bit A / D converter), the pulse The range to capture as wave data becomes wider.

  The count value of the pulse signal is transmitted from the microcomputer 37 to the personal computer 4 through the USB communication circuit 38 as a pulse wave signal. By using a wired communication means, it is difficult for problems such as communication interruption to occur. The personal computer 4 performs various types of data analysis to calculate the period, pulse, and amplitude of the pulse wave. These are displayed on a monitor or stored. When the stress determination is performed using data such as amplitude, the result is also displayed or stored.

According to the pulse wave measuring apparatus 1, since the pulse wave is measured while using the force with which the subject presses the fingertip, the pulse wave information can be acquired stably and accurately. Moreover, since the light shielding property is excellent, the measurement accuracy can be improved. Since the shape of the main body 2 matches the posture of a human finger, it can be gripped without excessive force. Since the main body 2 is shaped to be easily gripped, measurement while pressing the abdomen of the fingertip is easy.
Since the load monitor 12 is provided, an appropriate pressure can be notified to the subject with good visibility. Since one load monitor 12 is provided on each of the left and right, measurement can be performed regardless of whether the dominant hand is on the left or right.
Since the case lid 63 is opened so that the sensing position Ps can be confirmed with one's own eyes, a finger is placed at an appropriate position. Note that the case lid 63 need not always be opened.
Since the impervious material 65 is provided in the finger insertion portion 3 to block disturbance light entering the pulse wave sensor 22, only light that has passed through the fingertip can be captured.

Note that the present invention can be widely applied without being limited to the above-described embodiment.
For example, pulse wave measurement may be performed using visible light or infrared light other than red.
The main body 2 may be shaped so as to be placed with the hand open as long as the subject can apply an appropriate pressure. The determination result may be displayed on the personal computer 4 without providing the load monitor 12 in the main body 2.
An unevenness or the like may be provided in the finger insertion portion 3 so that the finger insertion portion 3 is guided to the sensing position Ps by touch.
A configuration in which the pulse wave sensor 22 is in close contact with the fingertip without providing the shield member 78 may be used. The LED 21 and the pulse wave sensor 22 may be arranged in the insertion direction.
The light emitting element may be an element other than the LED 21, such as a phototransistor. The pulse wave sensor 22 may be a light receiving element that outputs an analog signal. The temperature sensor 23 and the pressure sensor 24 are not limited to the embodiment.

The finger insertion part 3 may be made of a light shielding material such as metal. In this case, the non-permeable material 65 is not necessarily provided.
An elastic body other than the rubber 84 may be used. Instead of providing the bearing portion 82, the shaft 81 can be passed through the main body portion 2. The bearing portion 82 may be provided on the finger insertion portion 3 side, and the shaft 81 may be provided on the main body portion 2.
The load monitor 12 may be composed of a 7-segment LED or a simple LCD monitor (liquid crystal monitor).
The removal of the capacitance may be performed by bringing the main body unit 2 into contact with the hand without performing the removal in the finger insertion unit 3.
A wireless communication technique may be used for data communication between the pulse wave measuring device 1 and the personal computer 4.

1 is an external view of a pulse wave measurement device according to an embodiment of the present invention. It is a block diagram of a pulse wave measuring device. It is a figure which shows the structure of a pulse wave detection circuit. It is a figure which shows the structure of a temperature detection circuit. It is a side view of a pulse wave measuring device. It is a top view of a pulse wave measuring device. It is a figure which shows the outline of the structure which operates a load monitor. It is the figure which opened the case cover part. It is a B arrow view of FIG. It is sectional drawing along CC line of FIG. It is sectional drawing along the DD line | wire of FIG. It is sectional drawing along the EE line of FIG. It is a figure which illustrates a load range and a pressure sensitive range typically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pulse wave measuring device 2 Main-body part 3 Finger insertion part 12 Load monitor 21 LED (light emitting element)
22 Pulse wave sensor (light receiving element)
23 temperature sensor 24 pressure sensor 51 opening 65 non-permeable material 76 GND pin 81 shaft (rotating shaft)
84 Rubber (elastic member)

Claims (8)

A finger insertion part in which a fingertip of a subject can be inserted and a light emitting element and a light receiving element are arranged toward the abdomen of the fingertip;
A main body part that rotatably supports the finger insertion part with the near side in the insertion direction of the fingertip as a fulcrum;
With
The finger insertion portion has a rotation shaft extending in a direction orthogonal to the pressing direction when the abdomen of the fingertip is pressed toward the light receiving element and the insertion direction of the fingertip, and an elastic member protrudes in the pressing direction at the bottom. Provided,
The main body is formed with a pressure sensor with which the elastic member can contact and an opening having a shape into which a part of the finger insertion portion is inserted and only the finger insertion portion is allowed to rotate. Characteristic pulse wave measuring device.   The pulse wave measuring device according to claim 1, wherein the finger insertion portion is disposed to be inclined with respect to the main body portion, and a back side in the insertion direction is lowered from a near side.   2. The pulse according to claim 1, wherein the main body portion is provided with one load monitor for displaying a magnitude of a detection value of the pressure sensor on a side portion in a left-right direction sandwiching the finger insertion portion. Wave measuring device.   The pulse wave measuring device according to claim 1, wherein an impermeable material is provided on an inner surface of the finger insertion portion.   The said finger insertion part is provided with two or more said light emitting elements on both sides of the said light receiving element, The distance from the said light receiving element differs in these light emitting elements. Pulse wave measuring device.   The pulse wave measuring device according to claim 4, wherein the finger insertion unit includes a temperature sensor that detects a temperature of a fingertip across the light receiving element, and a pin that is grounded.   The pulse wave measuring device according to claim 5 or 6, wherein the light receiving element outputs a pulse signal having a different frequency according to a light amount.   The pulse wave measuring device according to claim 1, wherein a concave portion for avoiding a nail is provided on an inner surface of the finger insertion portion on the back side in the insertion direction.

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