KR20050048932A - A portable spirometer for measuring lung capacity and respiration gas - Google Patents

Abstract

The present invention relates to a portable lung function analysis device for simultaneously measuring the lung capacity and the amount of a specific respiratory gas, the body comprising an air tube; An infrared spectroscopic unit including an infrared light source, an optical filter, and an infrared sensor for measuring an amount of a specific respiratory gas flowing from the air tube; A spirometry unit comprising a spirometry sensor for measuring the lung capacity with the respiratory gas introduced from the air tube; A signal processing unit including a signal amplifier, a signal processor, a storage unit, an indicator, and a signal transmitter for processing signals output from the infrared sensor and the spirometry sensor; And a control unit including a reference gas and a reference gas tank for correcting the measured value for the respiratory gas, wherein each unit may operate independently of each other.

Description

Portable pulmonary function analysis device that simultaneously measures lung capacity and respiratory gas

The present invention relates to a portable lung function analysis device for simultaneously measuring the lung capacity and respiratory gas. Specifically, the present invention relates to a portable pulmonary function measuring device for measuring the amount of respiratory gas according to the infrared absorbance at the time of measuring the spirometry using a portable spirometry with an infrared sensor.

The spirometer is used to diagnose the presence and extent of circulatory dysfunction by measuring various indicators such as lung capacity and effort lung capacity. In the conventional spirometry, a Benedict-Roth type, in which a metal inner cylinder is floated in a double cylindrical water tank and directly measures a change in the amount of airflow, has been used. However, in order to measure rapid changes such as forced calling, a light plastic inner cylinder is used, and the change of the inner cylinder is converted into an electrical signal by a potentiometer and measured and differentiated to obtain an air flow rate. Types that draw flow curves are becoming popular. The same type includes wedge type and box type. In addition, a small portable spirometer which measures the airflow velocity directly using a flowmeter using the Hagen-Poiseuille law and the King's law on the fluid, and the airflow rate is determined by its integration. Widely used as simple type.

The conventional method of measuring the respiratory gas consists of a module for measuring oxygen and carbon dioxide separately in the spirometer, there is a module for measuring oxygen, and a module for measuring carbon dioxide, when the respiratory gas passes the module Each module reacts. And the reaction degree is output as an electric signal, and the spirometry displays the amount of oxygen and carbon dioxide according to the electric signal. If the device is used repeatedly for a certain level, it needs to be replaced due to the end of its component life. As a conventional respiratory gas measurement method, a diaphragm galvanic cell method, a solid electrolyte method, a semiconductor method, or the like may be commonly used.

Pulmonary function was measured by measuring spirometry and lung respiratory gas in spirometry and respiratory gas meter in a medical institution during the health examination process. Existing spirometry is using a separate device to measure respiratory gas volume. The gas is stored separately and then measured. This mechanism is complicated in device configuration, and the replacement of filters due to frequent use has become a problem. In addition, in order to measure the spirometry and the amount of gas contained in the breathing can be measured only in a special place equipped with a spirometry room there was a time and place constraints in the measurement.

Portable spirometry has been manufactured and used for the purpose of easily measuring the lung capacity during exercise. However, in this case, the patient can not measure the amount of spirometry and the amount of respiratory gas at the same time, it is inconvenient to measure separately.

The present invention relates to a portable pulmonary function analysis device attached to a portable spirometry device capable of measuring the amount of gas contained in the respiration according to infrared absorption by applying non-dispersive infrared spectroscopy, measuring the spirometry and at the same time breathing It also offers the advantage of measuring the amount of gas. Through this, there is no need to collect respiratory gas, which was a problem in the existing lung function measuring equipment, and it is possible to use it for one-time use. It can eliminate the hassle of work and provide convenience for the doctor and the patient.

The present invention relates to a portable pulmonary function analysis device attached to a portable spirometry apparatus that can measure the amount of gas contained in the respiration according to the infrared absorption by applying a non-dispersed infrared method. Portable lung function analysis device according to the present invention is to measure the lung capacity and at the same time easy to measure the amount of respiratory gas.

Portable lung function analysis device of the present invention is composed of the following components.

A main body having a handle shape at the bottom and including a hollow air tube positioned across the center portion, and a correction button electrically connected to the signal processing unit;

An infrared spectrometer unit including an infrared light source, an optical filter, and an infrared sensor for measuring an amount of respiratory gas flowing from the air tube;

A spirometry unit comprising a spirometry sensor for measuring the lung capacity with the respiratory gas introduced from the air tube;

A signal processing unit including a signal amplifier, a signal processor, a storage unit, an indicator, and a signal transmission unit for processing signals output from the infrared sensor and the spirometry sensor, respectively; And

A control unit comprising a reference gas and a reference gas tank for correcting the measured value for the respiratory gas, characterized in that each unit can operate independently of each other, the spirometry and respiratory gas can be measured simultaneously It is a portable lung function analysis device.

In the portable lung function analysis apparatus of the present invention, the main body may further include a temperature measuring device. In addition, in the portable lung function analysis apparatus of the present invention, the optical filter is characterized by consisting of at least one detector filter and at least one reference filter. In the portable lung function analysis apparatus of the present invention, the infrared light source is characterized in that the tungsten filament.

In general, there are noises caused by environmental factors such as temperature and humidity when measuring lung function, and these noises affect the measurement of respiratory gas. Therefore, in order to compensate for noise, it is necessary to use as a reference gas a gas which knows the infrared absorbance according to temperature and humidity. To this end, in the present invention, a tank storing a reference gas is provided as a control unit. Here, the material of the tank for reference gas should be a material that does not have infrared attenuation or knows the degree of attenuation.

As used herein, the term "vital capacity" means the maximum amount of air entering and exiting the lungs by one intake and exhalation. This is one of the test items for lung function. There are two types of spirometers used for measuring spirometry: rotary and cylindrical. When measured with a rotary spirometer, the subject is in a comfortable position, holding the ball in one hand, drinking enough air with his face slightly upward, and then spitting as much air as possible. A few measurements are repeated and the maximum is taken as the spirometry. The magnitude of the lung capacity is related to the size of the rib cage and the strength of the respiratory muscles. The lung capacity increases with the development of the body, and the relationship with the size of the body is close, so the comparison of the lung capacity must take into account the size of the sex, age, and body. The spirometry is used clinically as a test item to examine the ventilation ability of patients with respiratory diseases. The significance of lung ventilation in athletes is due to the relationship between oxygen intake during exercise. In this case, the meaning of the spirometry measured at steady state is clear, but it is very difficult to evaluate the lung ventilation capacity alone.

As used herein, the term "breathing" refers to gas exchange between the living body and the outside world, and since blood is intermediated, changes in the composition of air entering and exiting the lungs or changes in the composition of blood circulating in the lungs and tissues. Knowing the mechanism of gas exchange can be understood. It is the alveolar air that is involved in gas exchange in the lungs. The alveolar air is defined as when a larger arc is taken after a stable arc, and its composition can be measured by a suitable gas analyzer. Since gas movement is a pressure difference, the partial pressure of oxygen or carbon dioxide contained in the alveolar air is important information.

As used herein, the term “breathing gas” refers to a gas generated in aerobic gas, wherein nitrogen (N ₂ ), oxygen (O 2), and carbon dioxide (CO 2) are mainly used, and the normal range of the respiratory gas having a medical meaning is nitrogen. 79%, oxygen 20.93% and carbon dioxide 0.03%. In the present invention, the measurement of respiratory gas is a concept that is distinguished from the measurement of the lung capacity, and means that the amount of air used when breathing is measured.

In measuring respiratory capacity, measuring the lung capacity means to measure the amount of air that a person uses when breathing. Measuring respiratory gas is a measure of how much oxygen and carbon dioxide make up this amount of air. In other words, the general public (people without lung disease) inhale about 500 ~ 600mL of air once in one breath, nitrogen, oxygen, carbon dioxide occupies about 79%, 20.93%, 0.03%. However, in patients with lung diseases (lack of oxygen in breathing air, lack of ventilation, lack of diffusion of alveolar membrane, lack of circulation, disturbance of oxygen use, etc.), the amount of air during breathing is less than that of the general public. In addition, the ratio of oxygen and carbon dioxide is slightly different. For example, oxygen is normal but the amount of carbon dioxide is low, or the amount of carbon dioxide is high but the amount of oxygen is low, or both the amount of oxygen and carbon dioxide is low. Non-dispersive infrared methods measure the amount of oxygen and carbon dioxide contained in the breath and can easily determine whether lung disease. Therefore, the portable lung function analysis apparatus according to the present invention provides an advantage that a patient with poor lung function such as lung disease can easily measure the lung capacity and respiratory gas at any time by simply measuring the lung capacity and respiratory gas.

The configuration of the portable lung function analysis apparatus according to the present invention will be described in detail as follows.

end. Body: It is composed of each unit is combined, the upper is the infrared light source 10 is located, the front air tube (2) is located, the lower portion can be a handle to hold by hand. In addition, it may include a temperature measuring device, which is necessary for calibration when the infrared measurement accuracy of the reference gas is sensitive to temperature. In addition, a calibration button 13 is provided on the exterior of the main body 12, and electrically connected to the signal processing unit 4 located inside the main body, so that the correction of the signal processing before the inhalation gas is adjusted in advance. do. The air tube (2) is the part that the examinee blows the exhalation into the device, the tank 11 for the reference gas is attached to the opposite side.

I. Infrared spectroscopy unit: A part for measuring the degree of infrared absorption by injecting light from the infrared light source 10 to the gas introduced into the device. The infrared spectroscopic unit consists of an infrared light source 10, an optical filter 9 and an infrared sensor 8. The infrared sensor 8 enters the infrared sensor 8 through filtered gas through the gas, and generates an output signal according to the amount of incident light. The optical filter 9 filters the infrared rays generated by the infrared light source 10 into two kinds of infrared rays (for the main detector and the reference detector) having a specific wavelength according to each gas.

The infrared light source 10 may be formed of, for example, a resistor such as nichrome wire, silicon carbide, or tungsten. Although may be embodied in various forms, filament forms are representative. Infrared rays are generated by heating the filament with current.

The optical filter 9 may be composed of schott optical glass, UV grade quartz, Fused Sillca, Float glass, White glass, etc. By using such an optical filter 9, applications such as a low pass filter (LPF), a high pass filter (HPF), and a band pass filter (BPF) are possible.

The infrared sensor 8 includes a pyroelectric sensor, a thermopile sensor, and a thermistor borometer sensor, which are thermal sensors, and a quantum sensor includes a sensor using semiconductors such as HgCdTe, PbS, and InSb. All sensors can be applied to non-dispersive infrared methods.

All. Spirometry unit; The spirometry sensor (1) as a component, and measures the patient's spirometry. In the present invention, the existing spirometry sensor 1 can be used, and the portable spirometry can be applied to analogue, programmable, and digital spirometry.

la. Signal processing unit: This part processes the signals output from the spirometry sensor 1 and the infrared sensor 8, respectively. It consists of a signal amplifier 3, a signal processor 4, a storage section 5, an indicator 6 and a signal transmission section 7. The signal amplifier 3 amplifies the signal received from the spirometry sensor 1 and the signal received from the infrared sensor 8 to a desired signal level, respectively. The signal processor 4 serves to change the input analog signal into a digital value. In addition, this part deals with the compensation by noise in the measurement environment. The storage unit 5 stores the converted digital value in a static random access memory (SRAM) or a flash memory. The display part 6 is a part which displays the lung capacity and the amount of breathing gas, and can display it with LCD, 7 segments, etc. The signal transmitter 7 is a part for transmitting the converted digital value to a PC, PDA, or cellular phone by various transmission means such as RS232.

hemp. Control unit: Consists of a reference gas and a tank 11 for the reference gas. The reference gas is a gas whose infrared absorptivity is already known according to the surrounding environment such as temperature and humidity. The reference gas tank 11 is a tank for storing the reference gas, and the appearance of the reference gas tank 11 should be a material having no infrared attenuation or a degree of attenuation. The shape of the tank for the reference gas may be round, square, hexagonal, etc., depending on the air tube, and the handle is at the end.

The units can operate independently of each other.

The apparatus of the present invention will be described in detail with reference to the drawings.

1 shows the configuration of an apparatus according to the present invention, as shown in FIG. 1, an infrared light source 10, an optical filter 9 for filtering infrared light to a specific wavelength, and an infrared sensor 8 for absorbing infrared light. ) To construct a non-dispersive infrared gas measurement circuit. When the exhalation enters the air tube, the spirometry and infrared absorbance are measured by the spirometry unit 1 and the infrared sensor 8, respectively.

2 shows a configuration of the tank 11 for the reference gas according to the present invention. As shown in FIG. 2, the tank 11 for storing the reference gas and the reference gas which knows the infrared absorbance according to the noise and A handle is needed to push this tank 11 into the air tube 2.

Figure 3 shows how the device according to the invention works. The air tube 2 is connected to the spirometry unit and the infrared spectroscopy unit, respectively, to measure the breathing gas introduced into the air tube 2 by the infrared sensor 8 and the spirometry sensor 1, respectively. The measured value is corrected by the signal processing unit and output to the display unit 6.

The method of use of the device according to the invention can be described as follows.

As shown in the flowchart of the method of use by the user of FIG. 4, the user first presses the correction button 13 to correct it. Then, the tank 11 for reference gas is pushed into the air tube 2. Then, the degree of correction is automatically detected. Here, the automatic detection process is performed in the digital unit or PC, PDA, etc. built in the spirometer. And after pulling out the tank 11 for the reference gas, the user breathes inward to the mouth to the air tube (2). In other words, the air is sucked into the air tube 2. At the same time, the amount of gas contained in the breath is measured through a non-dispersive infrared method.

5 is a flowchart illustrating the correction process of FIG. 5, which is a detailed description of the dotted line part of FIG. 4. When the user presses the correction button 13, the signal processing unit enters a state for measuring the degree of correction. Infrared rays are absorbed by the reference gas while passing through the tank 11 for the reference gas, which is inserted into the air tube 2, and attenuation occurs. The degree of this attenuation is measured by the infrared sensor 8 and compared with known values. Through this comparison process, the degree of correction by ambient temperature, humidity, etc. is determined. The degree of correction is stored in the signal processing unit and then corrected by multiplying the measured value when measuring breathing gas.

Looking at a specific embodiment of the present invention.

The amount of gas contained in the breath can be measured according to the infrared absorption of each gas. Herein, carbon dioxide will be described in detail. First, the tank 11 for reference gas is put inside the air tube 2, and the noise of the surrounding environment at the time of a measurement is measured. Through this process, the compensation range for noise is obtained. The compensation according to this noise is multiplied in proportion to the amount of gas measured by the signal processing section 4. In the case of spirometry, the patient exhales air into the air tube 2, the spirometry sensor 1 measures the spirometry. In addition, power is supplied to the tungsten filament of long life to generate infrared rays. The generated infrared rays are filtered by infrared rays of a specific wavelength through two optical filters 9. The two filtered infrared rays are used as the light source for the active detector and the light source for the reference detector. The light source for the main detector has a 4.2 μm infrared wavelength with a high carbon dioxide absorption rate, and the light source for the reference detector has a 5 to 13 μm infrared wavelength with a low carbon dioxide absorption rate. The infrared rays from the main detector light source are absorbed by carbon dioxide while passing through the respiratory gas and then incident on the infrared sensor 8 to generate an output signal proportional to the incident amount. In addition, the infrared rays from the light source for the reference detector are incident on the infrared sensor 8 with little attenuation by carbon dioxide while passing through the breathing gas, and generate an output signal corresponding thereto. That is, the reference detector provides a reference value for measuring the amount of carbon dioxide, and the main detector provides a signal that changes with the amount of carbon dioxide. The relationship between the output signals from the two infrared sensors is as follows.

Fa = 1- [S1 / (R.S2)]

S1: Output signal value of main detector (peak to peak)

S2: output signal value of the reference detector (peak to peak)

R = S1 '/ S2' (S1 'and S2' are values of S1 and S2 measured under 0% carbon dioxide (100% N2))

The output signals of the main detector and the reference detector are amplified to the desired signal level by the signal amplifier 3, the noise is removed by the signal processing section 4, converted into digital values, and the digital values are stored in the storage section 5 And, the display unit 6 displays the amount of carbon dioxide, and is transmitted to the PC, PDA, mobile phone by various methods (RS232) through the signal transmission unit (7).

The foregoing description illustrates and points out the novel features of the invention that may be applied in various embodiments, and the novel features of the invention may be varied in the form of apparatus or methods illustrated by those skilled in the art within the spirit of the invention. Modifications are possible. Many modifications to the basic design are possible in other embodiments. The scope of the invention is defined by the claims that follow rather than by the foregoing description. Changes within the scope of the claims and equivalents are included within the scope of the present invention.

The present invention is a portable pulmonary function analysis device that can measure respiratory gas and at the same time measuring the spirometry, it is more convenient for doctors and patients by eliminating the inconvenience of the prior art to measure the spirometry and the amount of respiratory gas individually Can be provided. In addition, the portable pulmonary function analyzer of the present invention is small in size and easy to carry, so that patients with abnormal pulmonary function can measure lung function at any time.

1. External view of the device according to the present invention

2 is an external view of a tank apparatus for reference gas according to the present invention

3. Flowchart of execution of the device according to the present invention

4. Flow chart of the method of using the device according to the present invention

Figure 5 is a flow chart for the calibration process in the device according to the invention

 * Explanation of symbols for the main parts of the drawing:

1: spirometry sensor

2: air tube

3: signal amplifier

4: signal processing unit

5: storage

6: display unit

7: signal transmission unit

8: infrared sensor

9: optical filter

10: infrared light source

11: tank for reference gas

12: main body

13: Correction button

Claims (6)

A main body including an air tube; An infrared spectroscopic unit including an infrared light source, an optical filter, and an infrared sensor for measuring an amount of a specific respiratory gas flowing from the air tube; A spirometry unit comprising a spirometry sensor for measuring the lung capacity from the breathing gas introduced from the air tube; A signal processing unit including a signal amplifier, a signal processor, a storage unit, an indicator, and a signal transmitter for processing signals output from the infrared sensor and the spirometry sensor; And Control unit including the reference gas and the reference gas tank for correcting the measured value for the breathing gas Including, each unit is a portable lung function analysis device that can measure the lung capacity and respiratory gas at the same time that can operate independently of each other. The portable lung function analysis of claim 1, wherein the main body has a handle shape at a lower portion thereof, and includes a hollow air tube positioned across the center portion, and a correction button electrically connected to the signal processing unit. Device. The portable lung function analysis apparatus according to claim 1, wherein the main body further includes a temperature measuring device. The portable lung function analysis apparatus according to claim 1, wherein the optical filter comprises at least one detector filter and at least one reference filter. The portable lung function analysis apparatus according to claim 1, wherein the infrared light source is tungsten filament. The portable lung function analysis apparatus according to claim 1, wherein the reference gas tank is provided on an opposite side of the air tube.