KR101125236B1 - Pulse wave sensor module and pulse wave measurement apparatus using the same - Google Patents

Abstract

PURPOSE: A pulse wave sensor module and a pulse wave measurement apparatus using the same are provided to measure pulse wave having high precision by removing the external noise from a pulse wave signal at an output terminal. CONSTITUTION: A power terminal receives power from a power supply unit. A ground terminal is connected to a frame ground. A pulse wave detection sensor(100) detects a pulse wave and changes it into a voltage signal. A high pass filter(210, 220) removes noise. A first amplifier(300) amplifies the component of the pulse wave signal into a desired size.

Description

Pulse wave sensor module and pulse wave measuring device using the same {PULSE WAVE SENSOR MODULE AND PULSE WAVE MEASUREMENT APPARATUS USING THE SAME}

The present invention relates to a pulse wave sensor module for detecting a pulse wave of the human body and a pulse wave measuring apparatus using the same.

Pulse wave detection of the human body is a method for diagnosing various diseases, and is widely used not only in oriental medicine but also in western medicine.

In oriental medicine, pulsation was detected mainly through palpation, and in western medicine, pulse wave detection was performed through an invasive method of directly injecting a tube into a blood vessel to detect a change in blood pressure.

Recently, however, pulsation sensors have been developed that can objectize the progress of oriental medicine, and diagnostic devices have been developed in Western medicine that can detect pulse waves in a non-invasive way.

The pulse wave sensor developed so far is a pulse sensor using a magnetic thin film (Korea Patent No. 730385), a pulse sensor using a Hall element (Korea Patent No. 849383), a pulse sensor using a vertical magnetic anisotropic spin valve magnetoresistive element (Korea Patent No. 883407), a pulse sensor using an imaging device (Korean Patent No. 949457), but a medical pulse sensor (Korea Patent Publication No. 2001-0028668), non-invasive continuous blood pressure, mainly using a pressure sensor, Arterial elasticity measuring device (Korean Registered Patent No. 877207).

Each of the prior arts has advantages, but it has been difficult to accurately detect a pulse wave to effectively detect a weak pulse and diagnose various diseases.

In particular, vascular and cardiovascular diseases such as arteriosclerosis and myocardial infarction are widespread due to changes in meat-based eating habits, but diagnostic equipments for preventing and preventing such diseases have been required in advance. A relationship analysis device (Korea Patent No. 1019239) and a cerebrovascular analysis device (Korea Patent Publication No. 2010-0061619) have been developed.

The cardiovascular and cerebrovascular analysis apparatus precisely measures the accelerated plethysmogram (APG) waveform in the carotid, femoral and forearm as well as electrocardiogram (ECG) and phonocardiogram (PCG) waveforms. Blood flow rate showing vein elastic modulus (arterial stiffness), vein conformation, and functional change of blood vessels simultaneously showing vein elasticity (vasculature) in left and right coronary arteries or cerebrovascular branches This results in accurate and non-invasive calculation of blood flow resistance and blood flow rate.

By the way, conventionally known pulse wave measuring device is difficult to obtain the exact APG waveform required by the cardiovascular and cerebrovascular analysis device, APG waveform in the forearm is a certain pressure (about 10 to 15 mmHg) than the diastolic blood pressure Cuff-APG waveform should be obtained with a conventional Cuff sphygmomanometer under a certain pressure (about 20-30 mmHg) depressurized state than a pressurized state and systolic blood pressure, which was difficult to be used as an accurate measuring device.

Therefore, the pulse wave analysis circuit, the sensor module, and the pulse wave measurement using the pulse wave analysis circuit and sensor module, which can be easily and accurately used for diagnosing a diagnosis and can accurately obtain the pulse wave, such as the cardiovascular analyzer and the cerebrovascular analyzer, for use in various diseases. The devices and the like have been continuously developed.

It is an object of the present invention to provide a pulse wave sensor module and a pulse wave measuring device using the same, which effectively amplify weak pulses than conventional pulse wave sensors, effectively remove noise generated during measurement, and obtain a Cuff-APG waveform.

In order to achieve the above object, the pulse wave sensor module according to the present invention is a power terminal receiving power from the power supply of the main body, a ground terminal connected to the frame ground, the first output terminal for detecting the pulse wave and outputting a voltage signal; A pulse wave detection sensor including a second output terminal; Two high pass filters symmetrically connected in the same circuit configuration between the first output terminal of the pulse wave detection sensor and the frame ground and the second output terminal of the pulse wave detection sensor and the frame ground; And a first amplifier having an inverting terminal and a non-inverting terminal connected to each output terminal of the two high pass filters.

The high pass filter includes a first capacitor and a first resistor connected in series, and a contact point of the first capacitor and the first resistor serves as an output terminal of the high pass filter. Another characteristic of the pulse wave sensor module according to the present invention is that a second capacitor having a capacity of 1000 to 3000 times smaller than that of the first capacitor is symmetrically connected between each output terminal and the frame ground.

The first amplifier includes two amplifying stages for amplifying a signal input to an inverting terminal and a signal input to a non-inverting terminal, and noise having the same phase in the first signal and the second signal amplified in each of the amplifying terminals. Another feature of the pulse wave sensor module according to the present invention is configured as a differential amplifier stage to remove once more.

The two amplifier stages may include first and second internal amplifiers provided to input signals into non-inverting terminals, respectively; A second resistor connected between the inverting terminals of the first and second internal amplifiers; And two identical third resistors connected to each of the first and second internal amplifiers by negative feedback, wherein the differential amplifier stages are connected to the inverting and non-inverting terminals of each of the first and second internal amplifiers. A third internal amplifier; A fourth resistor connected between an output terminal of the first internal amplifier and an inverting terminal of the third internal amplifier; A fifth resistor connected to the negative feedback of the third internal amplifier; A sixth resistor connected between an output terminal of the second internal amplifier and a non-inverting terminal of the third internal amplifier; And a seventh resistor connected between the non-inverting terminal of the third internal amplifier and the frame ground, which is another feature of the pulse wave sensor module according to the present invention.

In addition, the fourth to seventh resistance is another feature of the pulse wave sensor module according to the present invention having the same size.

The low pass filter and the second amplifier are further connected to the output terminal of the first amplifier, which is another feature of the pulse wave sensor module according to the present invention.

The low pass filter includes an eighth resistor connected between an output terminal of the first amplifier and a non-inverting input terminal of the second amplifier, and a third capacitor connected between the non-inverting input terminal of the second amplifier and frame ground. And the second amplifier is negative feedback to the ninth resistor, and the tenth resistor is connected between the inverting input terminal of the second amplifier and the frame ground, and the inverting input terminal of the second amplifier is saturated with more than a power supply. Another feature of the pulse wave sensor module according to the present invention is that the amplification degree control circuit for controlling the amplification degree is further connected.

On the other hand, the pulse wave measuring apparatus according to the present invention includes a pressure sensor having a protruding portion opened on one side so that the pulsation is transmitted by air vibration, and a pressure sensor on which the power terminal, the ground terminal, the first output terminal and the second output terminal are formed; A power terminal, a ground terminal, a first output terminal and a second output terminal of the pressure sensor are connected to one side, and include two high pass filters and a first amplifier in a longitudinal direction, and receive power from the main body on the other side. A first printed circuit board having a first socket including a V _DD input terminal, a V _EE input terminal, a frame ground terminal, and an output terminal; And a first cable having one side connected to the first socket and the other side connected by a plug.

A second printed circuit board electrically connected to the first cable and mounted with a low pass filter and a second amplifier; It is another feature of the pulse wave measuring apparatus according to the present invention that the apparatus further comprises a third printed circuit board electrically connected to the second printed circuit board and equipped with a central processing unit.

The second printed circuit board and the third printed circuit board are mounted in a main body housing, and a second socket connected to the first cable is provided at one side of the main body housing, and a second connected to the second socket. The cable is connected to a third socket mounted on one side of the second printed circuit board, and the second printed circuit board and the third printed circuit board are connected to the fourth socket and the fifth socket formed on each side. It is another feature of the pulse wave measuring apparatus according to the present invention that is connected to.

The first printed circuit board may include: a frame ground line connected to a ground terminal of the pressure sensor and a frame ground terminal of the first socket; A V _DD supply line for connecting the power terminal of the pressure sensor and the V _DD supply terminal of the first amplifier and the V _DD input terminal of the first socket; And the agent of the V _EE supply end and the second between the first socket of the V _EE input end being the V _EE supply line formed to be connected, a first output terminal and the frame ground line of the pressure sensor and the pressure sensor of the first amplifier The two high pass filters are connected in the same circuit configuration between two output terminals and the frame ground line, and the inverting terminal and the non inverting terminal of the first amplifier are connected to each output terminal of the two high pass filters. It is another feature of the pulse wave measuring apparatus according to the present invention that the line is formed.

The high pass filter includes a first capacitor and a first resistor connected in series, and a contact point of the first capacitor and the first resistor serves as an output terminal of the high pass filter. Another characteristic of the pulse wave measuring apparatus according to the present invention is that a second capacitor having a capacity of 1000 to 3000 times smaller than the capacity of the first capacitor is symmetrically connected between each output terminal and the frame ground line.

The first amplifier includes two amplifying stages for amplifying a signal input to an inverting terminal and a signal input to a non-inverting terminal, and noise having the same phase in the first signal and the second signal amplified in each of the amplifying terminals. It is another feature of the pulse wave measuring apparatus according to the present invention that the differential amplifier stage is removed once more.

The two amplifier stages may include first and second internal amplifiers provided to input signals into non-inverting terminals, respectively; A second resistor connected between the inverting terminals of the first and second internal amplifiers; And two identical third resistors connected to each of the first and second internal amplifiers by negative feedback, wherein the differential amplifier stages are connected to the inverting and non-inverting terminals of each of the first and second internal amplifiers. A third internal amplifier; A fourth resistor connected between an output terminal of the first internal amplifier and an inverting terminal of the third internal amplifier; A fifth resistor connected to the negative feedback of the third internal amplifier; A sixth resistor connected between an output terminal of the second internal amplifier and a non-inverting terminal of the third internal amplifier; And a seventh resistor connected between the non-inverting terminal of the third internal amplifier and the frame ground, which is another feature of the pulse wave measuring apparatus according to the present invention.

The fourth and seventh resistors have the same magnitude, which is another feature of the pulse wave measuring apparatus according to the present invention.

The first printed circuit board has wiring lines formed such that an output terminal of the first amplifier and an output terminal of the first socket are connected, and a resistance is further connected between the power terminal of the pressure sensor and the V _DD supply line. Another aspect of the pulse wave measuring apparatus according to the present invention.

The second printed circuit board may further include: a frame ground line connected to a frame ground end of the third socket and a frame ground end of the fourth socket; A V _DD supply line for connecting the V _DD output terminal of the third socket and the V _DD input terminal of the fourth socket; And a V _EE supply line for connecting the V _EE output terminal of the third socket and the V _EE input terminal of the fourth socket, wherein a low pass filter is connected between the signal output terminal of the third socket and the frame ground line. In addition, the output line of the low pass filter is a further feature of the pulse wave measuring apparatus according to the present invention, characterized in that each wiring line is formed so that the second amplifier is further connected.

The low pass filter includes a third capacitor between the signal output terminal of the third socket and the non-inverting input terminal of the second amplifier, and a third capacitor between the non-inverting input terminal of the second amplifier and the frame ground line. Is connected, the second amplifier is negative feedback to the ninth resistor, a tenth resistor is connected between the inverting input terminal of the second amplifier and the frame ground line, the inverting input terminal of the second amplifier supply power abnormality Another characteristic of the pulse wave measuring apparatus according to the present invention is that a wiring line is further formed on the second printed circuit board so that the amplification degree control circuits for controlling the amplification degree so as not to saturate to each other.

The pressure sensor, the first printed circuit board, and the first cable portion are mounted in a cylindrical housing having a predetermined length, and the cylindrical housing has a cylindrical body surrounding the pressure sensor and the first printed circuit board. ; A fixing member fastened to the front of the cylindrical body to fix the open protrusion of the pressure sensor; A pulsation guide member which is fastened to the front of the fixing member and penetrates the center to induce and transmit air vibration of the pulsation; And a closing member fastened to the rear of the cylindrical body to surround a portion of the first cable.

In addition, the pulsation inducing member is an open fallopian tube that collects air vibrations of the pulsation is formed in the front or an open cylindrical tube formed so that it can be fitted to the branch tube of the cuff blood pressure monitor is another of the pulse wave measuring apparatus according to the present invention It features.

The pulse wave sensor module according to the present invention passes through two high pass filters, a first amplifier, and the like, which are symmetrically connected to the pulse wave signals obtained from two output terminals in addition to the ground terminal, and effectively removes external noise, and weak pulse wave signals. There is an effect that can be amplified to the desired size.

In addition, the pulse wave measuring apparatus according to the present invention not only enables effective noise removal and amplification of the pulse wave signal by using the pulse wave sensor module of the present invention, but also is convenient for use by separately mounting the pulse wave sensor module on one or more printed circuit boards. It is easy to replace parts, it is effective to measure the pulse wave in various ways.

1 is a circuit diagram showing an embodiment of a pulse wave sensor module according to the present invention.
FIG. 2 is a circuit diagram in which the pulse wave detection sensor 100 of FIG. 1 is replaced with the bridge circuit 101.
3 is a circuit diagram illustrating an internal structure of the first amplifier 300 of FIG. 1.
Figure 4 is a circuit diagram showing a circuit configuration that can be connected to the circuit of Figure 1 as another embodiment of the pulse wave sensor module according to the present invention.
5 is a perspective view showing a main portion cross-sectional view showing an embodiment of the pulse wave measuring apparatus according to the present invention.
6 is a perspective view showing a main portion cross-sectional view showing another embodiment of the pulse wave measuring apparatus according to the present invention.
7 is a conceptual diagram schematically showing a structure of a main body to which the plug 50 shown in FIGS. 5 and 6 is connected as another embodiment of the pulse wave measuring apparatus according to the present invention.
8 is a state diagram of use of the pulse wave measuring apparatus shown in FIG.
9 is a state diagram of use of the pulse wave measuring apparatus shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

[About pulse wave sensor module Example ]

One embodiment of the pulse wave sensor module according to the present invention basically, as shown in Figure 1, the power supply terminal 1, the ground terminal (3) connected to the frame ground (FGND), the power supplied from the power supply of the main body, pulse wave A pulse wave detection sensor 100 configured to include a first output terminal 2 and a second output terminal 4 for detecting and converting the signal into a voltage signal; Symmetrically connected in the same circuit configuration between the first output terminal 2 of the pulse wave sensor and the frame ground (FGND) and between the second output terminal 4 of the pulse wave sensor and the frame ground (FGND). Two high pass filters 210 and 220; And a first amplifier 300 having an inverting terminal 2 and a non-inverting terminal 3 connected to each output terminal V _2i (V _4i ) of the two high pass filters.

Here, the pulse wave detection sensor 100 may be used as long as it can detect the pulsation of the human body to convert the two voltage signals (V2, V4) based on the power supply terminal (1) and output. For example, a pulse sensor using a magnetic thin film (Korean Patent No. 730385), a pulse sensor using a Hall element (Korean Patent No. 849383), a pulse sensor using a vertical magnetic anisotropic spin valve magnetoresistive element (Korean Patent No. 883407) ) May also be used as the pulse wave detection sensor 100 of the present embodiment.

However, it will be described below using a pressure sensor as the pulse wave detection sensor 100 of the present embodiment. The pressure sensor configures the bridge circuit 101 with four identical resistors R, as shown in FIG. 2, between the power supply terminal 1 (Vs) and the ground terminal 3 (FGND). In this case, a change in resistance is caused to any one of the four resistors and sensed by a voltage signal V ₀ , thereby detecting a change in external pressure.

At this time, the output voltage signal (V ₀ ) of the pressure sensor, as shown in Fig. 2, the difference between the two node voltage (V _4- ) between the power supply terminal (Vs) and the ground terminal (FGND) in the bridge circuit 101 By sensing with V ₂ ), it is possible to effectively remove external noise as described later.

As described above, the two voltage signals V ₂ and V ₄ output through the pressure sensor 101 first remove DC component noise caused by the power supply terminal and irregular noise generated in the measurement, and pass only a signal having a predetermined frequency or more. To pass through each of the high pass filter (210, 220).

Here, each of the high pass filters 210 and 220 may be implemented with various circuit elements, but as shown in FIG. 2, between each output terminal V ₂ (V ₄ ) and the frame ground (FGND) of the pressure sensor 101. It is desirable to design the same circuit elements so as to be symmetrical so as to effectively remove in-phase noise from the first amplifier.

In FIG. 2, each of the high pass filters 210 and 220 is connected to the first capacitor C ₁ and the first resistor R ₁ in series, and the contacts of the first capacitor and the first resistor are connected to each of the high pass filters. It is to be the output terminal (V _2i ) (V _4i ) of, but is not necessarily limited thereto.

When the high pass filter is implemented as the first-order filter as shown in FIG. 2, the cutoff frequency ω _hc of the high pass filter is shown. Since is expressed as in Equation 1 below, the capacitance of the first capacitor C ₁ and the first resistance R to fall within the range of 1 <ω _hc <2 in consideration of the pulsation period, the power supply terminal, and the noise generated in the measurement. It is desirable to determine the size of ₁ ).

[Equation 1]

ω _hc = 1 / R ₁ C ₁

More specifically, the first capacitor C ₁ may be 0.2 kW, and the first resistor R ₁ may be 4.7 kW.

Signals passing through each of the high pass filters 210 and 220 may be input directly to the first amplifier 300, but as shown in FIG. 2, each output terminal V _2i (V _4i ) and a frame of the high pass filter are shown. Between the ground (FGND) it is preferable to further include a high-frequency noise reduction filter 230, 240 consisting of a second capacitor (C ₂ ) 1000 to 3000 times smaller than the capacity of the first capacitor (C ₁ ) symmetrically. Specifically, when the first capacitor C ₁ is 0.2 mW, the second capacitor C ₂ may be 100 mW.

By doing this, the pulse wave signal V _2i (V _4i ), which has further removed irregular noise having a high frequency component due to external equipment interference or the like, from the signals passing through the high pass filters 210 and 220 to the first amplifier 300. Will be entered.

Next, referring to FIGS. 2 and 3, the first amplifier 300 will be described. 3 is a circuit diagram showing the internal structure of the first amplifier 300 according to the present embodiment.

As shown in FIG. 3, the first amplifier 300 according to the present exemplary embodiment may respectively output pulse wave signals V _2i input to the inverting terminal 2 and pulse wave signals V _4i input to the non-inverting terminal 3, respectively. Two amplification stages 310 for amplifying and a differential amplifier stage 320 for removing noise having the same phase from the first signal V ₁ and the second signal V ₂ amplified by each of the amplification stages once more.

Here, the two amplifier stages 310, as shown in Fig. 3, the first and second internal amplifiers (A ₁ , A ₂ ) are provided so that the input signal (V _2i ) (V _4i ) to each of the non-inverting terminal (+), respectively. ); A second resistor R ₂ connected between the inverting terminals of the first and second internal amplifiers; And the same two third resistors R ₃ connected to each of the first and second internal amplifiers with negative feedback.

By the above configuration, the first signal V ₁ and the second signal V ₂ amplified by each amplifier stage are represented by the following equations (2) and (3), respectively.

[Equation 2]

V ₁ = [(R ₃ / R ₂ ) +1] V _2i - (R ₃ / R ₂ ) V _4i

&Quot; (3) &quot;

V ₂ = [(R ₃ / R ₂ ) +1] V _4i - (R ₃ / R ₂ ) V _2i

As can be seen from Equations 2 and 3, if the input signal V _2i (V _4i ) is noise having the same phase and magnitude (that is, V _2i = V _4i). ), Each output signal V ₁ (V ₂ ) of the first and second internal amplifiers A ₁ and A ₂ is equal to the input signal without amplification.

However, if it is a pure pulse wave signal without noise (i.e., V _2i = 0 and V _4i ≠ 0), the output signals V ₁ (V ₂ ) of the first and second internal amplifiers A ₁ and A ₂ are respectively − (R ₃ / R ₂ ) V _4i , to [(R ₃ / R ₂ ) +1] V _4i Will be amplified.

On the other hand, the differential amplifier stage 320 is, as shown in Figure 3, the first and second internal amplifiers (A _1, A ₂₎ each output (V ₁₎ (V ₂₎ of the inverting (-), a non-inverting (+) terminal A third internal amplifier A ₃ connected with the; A fourth resistor R ₄ connected between the output terminal V ₁ of the first internal amplifier and the inverting terminal (−) of the third internal amplifier; A fifth resistor R ₅ connected by the negative feedback of the third internal amplifier A ₃ ; A sixth resistor R ₆ connected between the output terminal V ₂ of the second internal amplifier and the non-inverting terminal (+) of the third internal amplifier; And a seventh resistor R ₇ connected between the non-inverting terminal (+) of the third internal amplifier and the frame ground (FGND).

Herein, when the fourth to seventh resistors of the differential amplifier stage 320 are the same, the output terminal signal V ₀₁ of the third internal amplifier A ₃ is the first and second internal amplifiers (Equation 4). It is represented by the difference between the output signals V ₁ and V ₂ of A ₁ and A ₂ .

&Quot; (4) &quot;

V ₀₁ = V ₂ - V ₁

Accordingly, when the output signals V ₁ and V ₂ of the first and second internal amplifiers A ₁ and A ₂ are identical from Equation 4, that is, as described above, the input signals V _2i and V are the same. _4i ) is noise with the same phase and magnitude (i.e., V _2i = V _4i) If), it can be seen that it can be effectively removed through the differential amplifier stage 320.

On the other hand, the pulse wave signal component is amplified by the following equation (5).

[Equation 5]

V ₀₁ = [(2R ₃ / R ₂ ) +1] V _4i

As described above, noise having the same phase and magnitude is effectively removed from the first amplifier 300 including the two amplifier stages 310 and the differential amplifier stages 320, and the pulse wave signal components include the second and third resistors R ₂ ,. It can be seen that by adjusting the R ₃ ) can be amplified to the desired size.

In particular, as shown in FIG. 3, the second resistor R ₂ is connected between pins 1 and 8 of the first amplifier 300, so that the second resistor R ₂ may be easily adjusted from the outside.

In addition, the V _DD input terminal 7 and the V _EE input terminal 4 of the first amplifier 300, as shown in Figure 2, by connecting a capacitance (C) of about 1㎌ between the frame ground (FGND), respectively, power supply noise It is preferable to remove.

Although not shown in FIG. 2, a predetermined resistor may be further connected between the power terminal V _S of the pressure sensor and the V _DD input terminal 7 of the first amplifier 300. That is, the power may be supplied to the power terminal V _S of the pressure sensor at the same size as the voltage supplied to the V _DD input terminal 7 of the first amplifier 300, but if necessary, through a predetermined resistance. The voltage may be lowered to supply power to the power terminal V _S of the pressure sensor.

The output pulse wave signal V ₀₁ of the first amplifier 300 obtained as described above may be directly sent to the signal processing analyzer of the central processing unit of the main body. However, as shown in FIG. And it is preferable to further pass through the low pass filter 500 and the second amplifier 600 to the second amplification.

Here, as illustrated in FIG. 4, the low pass filter 500 includes an eighth resistor connected between the output terminal 6 of the first amplifier 300 and the non-inverting (+) input terminal of the second amplifier 600. (R ₈ ) and a first filter including a third capacitor C ₃ connected between the non-inverting (+) input terminal of the second amplifier 600 and the frame ground (FGND).

When the low pass filter 500 is implemented as the primary filter as shown in FIG. 4, the cutoff frequency of the low pass filter is ω _lc. Since Equation 6 is expressed as Equation 6 below, the capacitance of the third capacitor C ₃ and the eighth resistor R ₈ are set within the range of 40 <ω _lc <50 in consideration of the measurable period of the pulsation and the noise of the high frequency component. It is desirable to determine the size of.

&Quot; (6) &quot;

ω _lc = 1 / R ₈ C ₃

More specifically, the third capacitor C ₃ may be 2.2 kV and the eighth resistor R ₈ may be 10 kV.

Meanwhile, as illustrated in FIG. 4, the second amplifier 600 is negatively fed back to the ninth resistor R ₉ , and is connected between the inverting (−) input terminal of the second amplifier 600 and the frame ground (FGND). Is connected to the tenth resistor (R ₁₀ ), and the inverting (-) input terminal of the second amplifier does not saturate the output signal (V ₀₂ ) more than the supply power supply (that is, not greater than V _DD or less than V _EE). It is preferable that the amplification degree control circuit 700 for adjusting the amplification degree is further connected.

In this case, the amplification degree control circuit 700, as shown in Figure 4, the supply voltage V _DD and Between the both ends of V _EE , the twelfth resistor R ₁₂ and the thirteenth resistor R ₁₃ of the same size are connected in series symmetrically with respect to the variable resistor R _v , and the variable resistor R _V and the second resistor are connected in series. The eleventh resistor R ₁₁ may be connected between the inverting (−) input terminals of the amplifier.

More specifically, the ninth resistor R ₉ is 60 mA, the tenth resistor R ₁₀ is 2 mA, the eleventh resistor R ₁₁ is 100 mA, the twelfth resistor R ₁₂ and the thirteenth resistor R ₁₃ ) may be 5 mV and the variable resistor R _v may be 20 mV.

Like the first amplifier 300, the V _DD input terminal 8 and the V _EE input terminal 4 also have a capacitance of about 1 dB between the frame grounds FGND, as shown in FIG. It is preferable to remove power supply noise by connecting (C).

In addition, the reference numeral 400 is a socket connected to the first amplifier 300, terminal 1 is the V _DD supply line, terminal 2 is the output terminal 6 of the first amplifier 300, and terminal 3 is the frame Ground (FGND) and terminal 4 are connected to the V _EE supply line, respectively.

[About pulse wave measuring apparatus Example ]

Next, an embodiment in which the pulse wave sensor module described above is separately mounted on at least one printed circuit board (PCB) and implements a pulse wave measuring apparatus will be described with reference to FIGS. 5 to 7.

5 and 6, the pulse wave measuring apparatus according to the present embodiment basically has a protrusion 12 open at one side so that the pulsation is transmitted by air vibration, and at the other side, a power terminal, a ground terminal, A pressure sensor 10 formed with a first output terminal and a second output terminal; A power terminal, a ground terminal, a first output terminal and a second output terminal of the pressure sensor are connected to one side 22, and include two high pass filters and a first amplifier in the longitudinal direction, and supply power from the main body to the other side. A first printed circuit board 20 having a first socket 24 having a V _DD input terminal, a V _EE input terminal, a frame ground terminal, and an output terminal; And one side is connected to the first socket 24 and the other side is configured to include a first cable 40 having a predetermined length connected by a plug (50).

Here, the first printed circuit board 20 is for configuring the circuit shown in FIG. 2, and the ground terminal 3 of the pressure sensor 101 and the frame ground terminal of the first socket 24 (not shown). Frame ground line for connection; A V _DD supply line for connecting the power supply terminal 1 of the pressure sensor 101 and the V _DD supply terminal 7 of the first amplifier 300 and the V _DD input terminal (not shown) of the first socket 24; And a V _EE supply line for connecting the V _EE supply terminal 4 of the first amplifier 300 to the V _EE input terminal (not shown) of the first socket 24.

In this case, the first printed circuit board 20 may further include a sensor-side socket 22 capable of simultaneously plugging and unplugging four pins of the pressure sensor 10 on the opposite side of the first socket 24.

In addition, between the first output terminal 2 of the pressure sensor 101 and the frame ground line and between the second output terminal 4 and the frame ground line of the pressure sensor 101 on the first printed circuit board 20. Two high pass filters 210 and 220 are connected in the same circuit configuration.

In addition, the first printed circuit board 20 has an inverting terminal 2 and a non-inverting terminal of the first amplifier 300 at each output terminal V _2i (V _4i ) of the two high pass filters 210 and 220. Wiring lines are formed to connect (3), respectively.

Here, the high pass filters 210 and 220 may be configured in various ways as described above, but as a minimum circuit element, as shown in FIG. 2, the first capacitor C ₁ and the first resistor R ₁ are in series. In this case, the first capacitor C ₁ and the contact of the first resistor R ₁ are the output terminals V _2i and V _4i of the high pass filter.

The second capacitor C having a capacity of 1000 to 3000 times smaller than the capacity of the first capacitor C ₁ is symmetrically between each output terminal V _2i (V _4i ) and the frame ground line of the two high pass filters. _It is preferable to further include a high frequency noise reduction filter 230, 240 consisting of ₂ ).

Meanwhile, as shown in FIG. 3, the first amplifier 300 includes two amplifying stages for amplifying the signal V _2i input to the inverting terminal 2 and the signal V _4i input to the non-inverting terminal 3, respectively. A first chip in the form of a single chip consisting of a differential amplifier stage 320 for removing the noise having the same phase from the first signal (V ₁ ) and the second signal (V ₂ ) amplified in each amplifier stage once more It is mounted to the printed circuit board 20.

Since the two amplifier stages 310 and the differential amplifier stage 320 of the first amplifier 300 have been sufficiently described in the embodiment of the pulse wave sensor module, repeated descriptions thereof will be omitted.

The output terminal 6 of the first amplifier 300 and the output terminal of the first socket 24 are connected to the first printed circuit board 20, the power supply terminal 1 of the pressure sensor 101 and the V _DD supply line. It is preferable that each wiring line is formed so that a resistance is further connected between them.

A part of the pulse sensor module, that is, the pressure sensor 10, the first printed circuit board 20 and the first cable 40 described above, has a predetermined length separated from the main body, as shown in FIGS. 5 and 6. Having a cylindrical housing (110) (120).

Here, the cylindrical housing 110, 120, as shown in Figure 5 and 6, the cylindrical body 30 surrounding the pressure sensor 10 and the first printed circuit board 20; A fixing member 32 fastened to the front of the cylindrical body to fix the protrusion 12 of the opening 14 of the pressure sensor; A pulsation guide member (35) (36), which is fastened to the front of the fixing member and penetrates the center to induce and transmit air vibration of the pulsation; And a closing member 31 fastened to the rear of the cylindrical body 30 to surround a part of the first cable 40.

As implied in FIGS. 5 and 6, only the configuration of the pulsation inducing members 35 and 36 may be different, and the configuration of the two embodiments may be the same, and the pulsation inducing members 35 and 36 may be detachable. It can be replaced with one of a different shape according to the purpose of use. When the pulsation guide member (35) 36 is replaced, an O-ring (33) made of an elastic material may be embedded in order to be connected to the fixing member 32 in an airtight manner.

The pulsation inducing member 35 of the embodiment shown in FIG. 5 is formed with an open fallopian tube 35 that collects air vibrations of the pulsation to the front, thereby effectively collecting air vibrations due to the pulsation and transmitting it to the pressure sensor 10. This is easy to measure the pulse wave of the carotid or femoral artery. Therefore, the embodiment of FIG. 5 may be called a carotid pulse wave detector or a femoral artery pulse wave detector, but pulse waves of other body parts may be easily and effectively measured in the same configuration.

FIG. 8 shows an example of measuring the right carotid artery with the carotid artery pulsometer 110 shown in FIG. 5.

In addition, the pulsation inducing member 36 of the embodiment shown in FIG. 6 is formed with an open cylindrical tube 37 to be fitted to the branch tube 122 of the cuff blood pressure monitor (not shown), thereby the cuff pulse wave (Cuff) -APG) Easy to measure That is, by connecting the branch tube 122 to the rubber tube connected to the pressure gauge of the conventional Cuff blood pressure monitor, and by inserting the cylindrical tube 37 open to the branch tube 122, a predetermined pressure (about 10 to 15 mmHg than the diastolic blood pressure) ) Cuff-APG waveforms by air waves can be easily obtained even under a reduced pressure (about 20 ~ 30 mmHg) than a pressurized state and systolic blood pressure. Thus, the embodiment of FIG. 5 may be called a cuff pulse wave detector.

9 shows an example of measuring the Cuff-APG waveform of the right forearm with the cuff pulse wave detector 120 shown in FIG. In FIG. 9, reference numeral 124 denotes a cuff, 126 an air vent, and 128 a pressure gauge.

Next, the mounting and the second amplifier 600 of the low pass filter 500 and the second amplifier 600 connected to the output terminal 6 of the first amplifier 300 described in the embodiment of the pulse wave sensor module. How the output terminal 1 of the present invention is connected to the central processing unit of the main body will be described.

The low pass filter 500 and the second amplifier 600 are mounted together on the first printed circuit board 20 in the cylindrical housings 110 and 120 shown in FIGS. 5 and 6, or in FIG. 7. Although it may be mounted together on the third printed circuit board 70 in which the central processing unit is mounted in the illustrated body housing 80, the second printed circuit board 60 may be separated in consideration of ease of use, fabrication of the substrate, and signal processing. It is preferable to mount on the s) and place it in the main body housing 80 as shown in FIG.

In the second printed circuit board 60, as well as the low pass filter 500 and the second amplifier 600, which are pulse wave sensor modules of the present invention, as well as the heart rate measurement sensor module may be mounted together with FIG. 7. Reference numeral 68 in FIG. 7 shows a position where the low pass filter 500 and the second amplifier 600 which are pulse wave sensor modules of the present invention are mounted.

On the other hand, one side of the main body housing 80 is provided with a second socket 84 for APG connected to the plug 50 of the first cable 40, the second cable 63 connected to the second socket 84 Is connected to the third socket 64 mounted on one side of the second printed circuit board 60.

The second printed circuit board 60 and the third printed circuit board 70 are connected to each other by a third cable 67 connected to the fourth socket 62 and the fifth socket 72.

In addition, the ECG socket 82 for ECG measurement and the PCG socket 86 for heart sound measurement are further provided in the main body housing 80, and each of the cables is connected to a socket 74 mounted on the third printed circuit board 70. 61 is connected to the socket 66 mounted on the second printed circuit board 60 by a cable 65.

Accordingly, the second printed circuit board 60 may include: a frame ground line for connecting the frame ground terminal FGND of the third socket 64 and the frame ground terminal FGND of the fourth socket 62; A V _DD supply line for connecting the V _DD output terminal of the third socket 64 to the V _DD input terminal of the fourth socket 62; And a V _EE supply line for connecting the V _EE output terminal of the third socket 64 and the V _EE input terminal of the fourth socket 62.

In addition, a low pass filter 500 is connected to the second printed circuit board 60 between the signal output terminal of the third socket 64 and the frame ground line, and the second amplifier 600 is connected to the output terminal of the low pass filter. Wiring lines are respectively formed to be further connected.

Specifically, the second printed circuit board 60 includes an eighth resistor R ₈ between the signal output terminal of the third socket 64 and the non-inverting input terminal of the second amplifier 600, and the second amplifier 600. The third capacitor C ₃ is connected between the non-inverting input terminal and the frame ground line of the wire line to form the low pass filter 500.

In order to connect the second amplifier 600, the second printed circuit board 60 is negatively fed back to the ninth resistor R ₉ , and between the inverting input terminal of the second amplifier 600 and the frame ground line. 10 resistance (R ₁₀ ) is connected, the wiring line is further formed so that the amplification degree control circuit 700 for controlling the amplification degree is not connected to the inverting input terminal of the second amplifier 600 so as not to saturate over the supply power. .

Since the amplification degree control circuit 700 has been sufficiently described in the embodiment of the pulse wave sensor module, repeated description thereof will be omitted.

By the above configuration, the power supply of the pressure sensor 10 of the pulse wave measuring apparatus according to the present embodiment is provided in the main body housing 80 separately or mounted on the third printed circuit board 70 (not shown). The V _DD output terminal of the fifth socket 72 is connected to the V _DD input terminal of the fourth socket 62 through the third cable 67, and the V _DD supply line formed on the second printed circuit board 60 is again connected. 3 is connected with the V _DD output end of the socket 64, it is connected with the V _DD output end of the second socket 84, back through a second cable 63, the first receptacle through the back the first cable 40 through It is connected to the V _DD input terminal of (24), and is connected to the power terminal (1) of the pressure sensor 10 through the V _DD supply line formed on the first printed circuit board 20, the drive power is supplied.

Here, when the V _DD supply voltage is higher than the driving voltage of the pressure sensor 10, a separate wiring formed between the V _DD supply line and the power terminal 1 of the pressure sensor 10 is formed on the first printed circuit board 20. By using a predetermined resistor to further connect.

In the same manner as the ground of the pressure sensor 10, the fifth socket 72-> third cable 67-> from the frame ground line of the third printed circuit board 70 connected to the metallic frame of the main body housing 80. Fourth socket 62-> Frame ground line of second printed circuit board 60-> Third socket 64-> Second cable 63-> Second socket 84-> First cable ( 40)-> first socket 24-> frame ground line of the first printed circuit board 20-> through the ground terminal 3 of the pressure sensor 10.

The V _EE power supply for driving the first amplifier 300 and the second amplifier 600 mounted on the first printed circuit board 20 and the second printed circuit board 60 is the same as the V _DD power and ground. It is supplied from the power supply provided in the main body.

As described above, since the power of the pressure sensor 10 is also supplied from a power supply device provided in the main body, there is no need to provide a separate driving power supply device.

In addition, the first output terminal 2 and the second output terminal 3 of the pressure sensor 10 is connected to the wiring line of the sensor-side socket 22 or the first printed circuit board 20 provided separately, The output terminal 6 of the first amplifier 300 is connected to the first socket 24-> first cable 40-> second socket 84-> through the wiring line of the first printed circuit board 20. 2 cable (63)-> third socket (64)-> second printed circuit board (60) is connected to the wiring line, and the output terminal (1) of the second amplifier (600) is the second printed circuit board (60). The wiring line of the fourth socket 62-> third cable 67-> fifth socket 72-> third printed circuit board 70 through the wiring line of the pressure sensor 10 The measured pulse wave signal is removed from the noise, amplified to the required size, and sent to the central processing unit mounted on the third printed circuit board 70.

As illustrated in FIG. 7, the third printed circuit board 70 may further include an input unit 92 and an output unit 94 outside the body housing 80.

Therefore, the pulse wave measuring apparatus of the present embodiment can be driven by the control of the input unit 92 and the central processing unit, and the result can be represented by the output unit 94.

10, 101: pressure sensor
20: first printed circuit board
24: first socket
30: cylindrical body
31: Finishing member
32: fixing member
34: pulsation inducing member
40: first cable
50: plug
60: second printed circuit board
62: fourth socket
63: second cable
64, 400: 3rd socket
67: third cable
70: third printed circuit board
72: fifth socket
80: body housing
100: pulse wave detection sensor
110: Carotid Artery Pulse Wave Finder, Femoral Artery Pulse Wave Finder
120: cuff pulse wave measuring instrument
130: main body
210, 220: High pass filter
230, 240: high frequency noise reduction filter
300: first amplifier
310: two amplification stages
320: differential amplifier
500: low pass filter
600: second amplifier
700: amplification degree control circuit

Claims (20)

A pulse wave detection sensor including a power terminal supplied with power from a power supply of the main body, a ground terminal connected to the frame ground, and a first output terminal and a second output terminal configured to detect and output a pulse wave into a voltage signal;
Two high pass filters symmetrically connected in the same circuit configuration between the first output terminal of the pulse wave detection sensor and the frame ground and the second output terminal of the pulse wave detection sensor and the frame ground; And
And a first amplifier having an inverting terminal and a non-inverting terminal connected to each output terminal of the two high pass filters.
The method of claim 1,
The high pass filter is configured by connecting a first capacitor and a first resistor in series,
The contact point of the first capacitor and the first resistor is an output terminal of the high pass filter,
And a second capacitor having a capacity of 1000 to 3000 times smaller than the capacity of the first capacitor is symmetrically connected between each output terminal of the two high pass filters and the frame ground.
The method according to claim 1 or 2,
The first amplifier further includes two amplifying stages for amplifying a signal input to an inverting terminal and a signal input to a non-inverting terminal, and noise having the same phase in the first signal and the second signal amplified in each of the amplifying terminals. Pulse wave sensor module, characterized in that consisting of a differential amplifier to remove.
The method of claim 3, wherein
The two amplification stages,
First and second internal amplifiers provided to input signals into non-inverting terminals, respectively;
A second resistor connected between the inverting terminals of the first and second internal amplifiers; And
And include two identical third resistors connected to each of the first and second internal amplifiers by negative feedback.
The differential amplifier stage,
A third internal amplifier connected to each of the output terminals of the first and second internal amplifiers to an inverting and non-inverting terminal;
A fourth resistor connected between an output terminal of the first internal amplifier and an inverting terminal of the third internal amplifier;
A fifth resistor connected to the negative feedback of the third internal amplifier;
A sixth resistor connected between an output terminal of the second internal amplifier and a non-inverting terminal of the third internal amplifier; And
And a seventh resistor connected between the non-inverting terminal of the third internal amplifier and the frame ground.
The method of claim 4, wherein
The fourth to seventh resistors are the pulse wave sensor module, characterized in that having the same size.
The method of claim 5, wherein
A pulse wave sensor module, characterized in that the low pass filter and the second amplifier is further connected to the output terminal of the first amplifier.
The method according to claim 6,
The low pass filter includes an eighth resistor connected between an output terminal of the first amplifier and a non-inverting input terminal of the second amplifier, and a third capacitor connected between the non-inverting input terminal of the second amplifier and frame ground. ,
The second amplifier is negative feedback to the ninth resistor,
A tenth resistor is connected between the inverting input terminal of the second amplifier and the frame ground;
A pulse wave sensor module, characterized in that the amplification degree control circuit for controlling the amplification degree is further connected to the inverting input terminal of the second amplifier so as not to saturate over the supply power.
A pressure sensor having a protruding portion opened at one side to transmit the pulsation through air vibration and having a power terminal, a ground terminal, a first output terminal, and a second output terminal at the other side;
A power terminal, a ground terminal, a first output terminal and a second output terminal of the pressure sensor are connected to one side, and include two high pass filters and a first amplifier in a longitudinal direction, and receive power from the main body on the other side. A first printed circuit board having a first socket including a V _DD input terminal, a V _EE input terminal, a frame ground terminal, and an output terminal; And
One side is connected to the first socket, the other side is a pulse wave measuring apparatus comprising a first cable having a predetermined length connected by a plug.
The method of claim 8,
A second printed circuit board electrically connected to the first cable and mounted with a low pass filter and a second amplifier;
And a third printed circuit board electrically connected to the second printed circuit board and mounted with a central processing unit.
The method of claim 9,
The second printed circuit board and the third printed circuit board are mounted in the body housing,
One side of the body housing is provided with a second socket connected to the first cable,
The second cable connected to the second socket is connected to the third socket mounted on one side of the second printed circuit board,
And the second printed circuit board and the third printed circuit board are connected by a third cable connected to the fourth and fifth sockets formed on each side.
The method of claim 10,
The first amplifier is formed such that an inverting terminal, a non-inverting terminal, and a V _EE supply terminal on the left side, and a V _DD supply terminal on the right side, respectively, with the concave semicircular groove formed at one end thereof facing up,
The first printed circuit board,
A frame ground line connected to the ground terminal of the pressure sensor and the frame ground terminal of the first socket;
A V _DD supply line for connecting the power terminal of the pressure sensor and the V _DD supply terminal of the first amplifier and the V _DD input terminal of the first socket; And
Being the V _EE supply line for the supply V _EE V _EE end and input end of the first socket connection formed of the first amplifier,
The two high pass filters are connected in the same circuit configuration between the first output terminal of the pressure sensor and the frame ground line and between the second output terminal of the pressure sensor and the frame ground line.
And a wiring line is formed at each output terminal of the two high pass filters to connect the inverting terminal and the non-inverting terminal of the first amplifier.
The method of claim 11,
The high pass filter is configured by connecting a first capacitor and a first resistor in series,
The contact point of the first capacitor and the first resistor is an output terminal of the high pass filter,
And a second capacitor having a capacity of 1000 to 3000 times smaller than that of the first capacitor is symmetrically connected between each output terminal of the two high pass filters and the frame ground line.
The method of claim 12,
The first amplifier further includes two amplifying stages for amplifying a signal input to an inverting terminal and a signal input to a non-inverting terminal, and noise having the same phase in the first signal and the second signal amplified in each of the amplifying terminals. Pulse wave measuring device comprising a differential amplifier stage to remove.
The method of claim 13,
The two amplification stages,
First and second internal amplifiers provided to input signals into non-inverting terminals, respectively;
A second resistor connected between the inverting terminals of the first and second internal amplifiers; And
And include two identical third resistors connected to each of the first and second internal amplifiers by negative feedback.
The differential amplifier stage,
A third internal amplifier connected to each of the output terminals of the first and second internal amplifiers to an inverting and non-inverting terminal;
A fourth resistor connected between an output terminal of the first internal amplifier and an inverting terminal of the third internal amplifier;
A fifth resistor connected to the negative feedback of the third internal amplifier;
A sixth resistor connected between an output terminal of the second internal amplifier and a non-inverting terminal of the third internal amplifier; And
And a seventh resistor connected between the non-inverting terminal of the third internal amplifier and the frame ground.
The method of claim 14,
The fourth to seventh resistance pulse wave measuring apparatus characterized in that the same size.
The method of claim 15,
The first printed circuit board is characterized in that the wiring line is formed so that the output terminal of the first amplifier and the output terminal of the first socket is connected, and a resistance is further connected between the power terminal of the pressure sensor and the V _DD supply line. Pulse wave measuring device.
17. The method of claim 16,
The third socket includes a frame ground terminal, a V _DD output terminal, a V _EE output terminal, and a signal output terminal.
The fourth socket includes a frame ground terminal, a V _DD input terminal, and a V _EE input terminal.
The second printed circuit board,
A frame ground line for connecting the frame ground terminal of the third socket and the frame ground terminal of the fourth socket;
A V _DD supply line for connecting the V _DD output terminal of the third socket and the V _DD input terminal of the fourth socket; And
A V _EE supply line for connecting the V _EE output terminal of the third socket and the V _EE input terminal of the fourth socket is formed,
A low pass filter is connected between the signal output terminal of the third socket and the frame ground line of the second printed circuit board.
Pulse line measuring device, characterized in that each wiring line is formed at the output terminal of the low pass filter so that the second amplifier is further connected.
The method of claim 17,
The second amplifier is formed to include an inverting input terminal and a non-inverting input terminal on the left side with the concave semicircular groove formed at one end thereof upward,
The low pass filter has an eighth resistor between the signal output terminal of the third socket and the non-inverting input terminal of the second amplifier, between the non-inverting input terminal of the second amplifier and the frame ground line of the second printed circuit board. To the third capacitor,
The second amplifier is negative feedback to the ninth resistor,
A tenth resistor is connected between the inverting input terminal of the second amplifier and the frame ground line of the second printed circuit board;
And a wiring line is further formed on the second printed circuit board such that an amplification degree control circuit for controlling an amplification degree is connected to the inverting input terminal of the second amplifier so as not to be saturated with a supply power supply.
The method according to any one of claims 8 to 18,
The pressure sensor, the first printed circuit board and the first cable portion are mounted in a cylindrical housing having a predetermined length,
The cylindrical housing,
A cylindrical body surrounding the pressure sensor and the first printed circuit board;
A fixing member fastened to the front of the cylindrical body to fix the open protrusion of the pressure sensor;
A pulsation guide member which is fastened to the front of the fixing member and penetrates the center to induce and transmit air vibration of the pulsation; And
The pulse wave measuring apparatus, characterized in that the closing member is fastened to the rear of the cylindrical body to surround a portion of the first cable.
The method of claim 19,
The pulsation inducing member is a pulse wave measuring device, characterized in that the open fallopian tube to collect the air vibration of the pulsation is formed in the front or an open cylindrical tube is formed in the front to be fitted to the branch tube of the cuff blood pressure monitor.

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