JP2017116430A - Exhalation component measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhalation component measurement device that improves the convenience while certainly suppressing exhalation.SOLUTION: The exhalation component measurement device body includes: a flow channel pipe 8 for passing exhalation; a gas sensor 9 for detecting the concentration of the gas contained in the exhalation passing through the flow channel pipe 8; and an inflow port 2a for the flow channel pipe 8 and a case. An attachment 6 for exhalation blow-in that includes, inside, a duct 6a for passing the exhalation and blows in the exhalation is attached to the inflow port 2a, and is connected to the flow channel pipe 8 and the duct 6a so as to make the exhalation flow through them. The inner diameter of the flow channel pipe 8 is set to be longer than the inner diameter of a flow-channel-pipe-side end 6d of the duct 6a.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an expiratory component measuring device that measures the concentration of a specific gas.

  A person's breath contains organic gases such as acetone and ethanol. By measuring how much the specific gas concentration is contained in the breath, we know what the person is in. be able to. As an apparatus for measuring the breath component of such a person, for example, Patent Document 1 discloses a breath component measuring apparatus.

  In the exhalation component measuring device described in Patent Literature 1, an exhalation flow path pipe that allows the breath exhaled by a person to pass through, and an exhalation introduction that surrounds the small diameter exhalation introduction hole and the exhalation introduction hole in the middle of the exhalation flow path pipe A hole sensor storage wall is provided, and a gas sensor is attached to the sensor storage wall so that an expiration storage space is formed between the expiration introduction hole and the gas sensor. In addition, a ventilation hole for ventilation with the outside is provided in a side portion of the expiration accumulation space. With this configuration, exhaled air that is blown by a person passes through the exhalation flow path pipe, the small-diameter exhalation introduction hole, and the exhalation accumulation space, and reaches the gas sensor. In this exhalation component measuring device, the exhaled breath passes through the exhalation introduction hole and the exhalation accumulation space, so that the inhaled exhalation directly hits the gas sensor and the sensor element of the gas sensor is cooled, and the sensor output is reduced. Preventing instability.

Japanese Patent No. 4740263

However, in the expiratory component measuring device described in Patent Document 1, the gas sensor measures the expiratory gas that passes through the expiratory introduction hole and the expiratory reservoir space without directly measuring the expiratory air present in the expiratory flow pipe. Will slow down the response.
There is also a region where the flow rate is not stable inside the flow path through which exhalation flows. Therefore, even if the gas sensor is arranged inside the flow path in order to improve the response, the output of the gas sensor may become unstable due to the influence of the flow velocity. For this reason, there is a problem in usability such that the measurement subject needs to blow exhalation at an appropriate flow rate.

  This invention is made | formed in view of the situation mentioned above, and makes it a solution subject to provide the expiration component measuring apparatus which improves the convenience, capturing an expiration | expired_air reliably.

  In order to solve the above problems, one aspect of an exhalation component measuring apparatus according to the present invention includes a flow channel tube that allows exhalation to pass through, a gas sensor that detects a concentration of gas contained in exhaled gas that passes through the flow channel tube, and the flow A case containing the passage tube and the gas sensor, and an inflow port formed in the case so as to communicate with the passage tube, and for inhaling exhalation from the outside of the case. When a blowing attachment having a conduit for guiding the exhaled breath is attached to the inflow port, a flow path through which the exhalation passes is formed, and the inner diameter is larger than the inner diameter of the conduit.

According to this aspect, in the flow path having the pipe line and the flow path pipe, the inner diameter of the flow path pipe is configured to be larger than the inner diameter of the end portion on the flow path side of the pipe line. It is assumed that the flow rate of the exhalation is faster in the area when it is assumed that the flow pipe is extended inside the flow pipe, and that the flow path is extended inside the flow pipe in other flow areas. The flow rate of exhalation can be made slower than the case area. Therefore, by disposing the gas sensor in a portion thereof the flow velocity becomes slow, breath to can be grasped reliably by the gas sensor, moreover, can be used without the measurement subject to moderate blowing breath, to improve the convenience .

  In the aspect described above, the flow channel pipe has an opening on the inner surface for introducing the exhaled gas inside the flow channel tube to the gas sensor, and the guide unit formed on the outer surface of the flow channel tube and the Attaching to the flow channel tube so as to be in close contact with a predetermined surface, an intake port for taking in exhaled air is formed in the predetermined surface, and the intake port is located inside the opening. In addition, it is preferable that the guide portion formed on the outer surface of the flow channel pipe is attached to the flow channel pipe so that the predetermined surface is in close contact therewith.

  Since the inner surface of the flow channel tube in which the opening is formed is a region other than the region when it is assumed that the pipeline is extended inside the flow channel tube in the above-described flow channel tube, the flow rate of exhaled air becomes slow. For this reason, exhaled gas reaches the gas sensor in a state where the flow rate becomes slow, so that exhaled gas can be reliably captured. In addition, since the gas sensor is attached to the flow channel tube so that the guide portion formed on the outer surface of the flow channel tube and a predetermined surface of the gas sensor are in close contact with each other, exhalation inside the flow channel tube passes through the air reservoir, etc. Therefore, the gas sensor can be quickly reached and the response of the gas sensor output can be improved.

  In the above-described aspect, it is preferable that the inner diameter of the channel pipe is 1.2 times or more and 2.5 times or less than the inner diameter of the pipe line. In this case, exhaled gas can be reliably taken into the gas sensor and stable measurement can be performed.

  In the above-described aspect, a pressure sensor for detecting the pressure in the flow path pipe, and a pressure transmission for connecting the flow path pipe and the pressure sensor to transmit the pressure in the flow path pipe to the pressure sensor. A pipe and an introduction pipe provided in the flow pipe for transmitting pressure to the pressure transmission pipe, and the flow pipe side end portion of the introduction pipe is disposed inside the flow pipe in the pipe line Is preferably included in the region assumed to be extended in the length direction of the flow pipe.

  In the above-mentioned channel pipe, the pressure is relatively high because the flow rate is high in the region assuming that the pipe line is extended inside the channel tube, and the pressure is relatively low in other regions because the flow rate is low. Become. Since the introduction pipe is provided so that the end portion of the introduction pipe on the flow channel side is included in the region, a relatively higher pressure than the side surface of the flow pipe can be transmitted to the introduction pipe. Therefore, the sensitivity of the pressure sensor for detecting the inhalation of exhalation can be made sharp.

In the above aspect, on the condition that the amount of change in pressure detected by the pressure sensor exceeds a first threshold and the amount of change in concentration of gas detected by the gas sensor exceeds a second threshold, It is preferable to provide a control unit that starts component identification.
Since the two elements such as the pressure and the gas concentration are used as the condition for starting the expiration component, the expiration measurement can be performed more quickly than when only the pressure is used as the condition for starting the expiration component. If only the pressure is a condition, it is necessary to increase the first threshold value because it is necessary to determine the breathing in by one element. In the present invention, not only the pressure but also the gas concentration is used as the determination condition, so the first threshold value can be lowered. As a result, it is possible to quickly measure expiration. Older people may have difficulty breathing in for a long time. According to this aspect, the breathing time can be shortened, so that the convenience of a subject who is weak in breathing such as an elderly person can be improved.

  In the above aspect, the control unit specifies the moving average value of the pressure, determines whether or not a difference between the pressure value of the current pressure and the moving average value of the pressure exceeds the first threshold, and the gas It is preferable to determine whether or not the difference between the current gas concentration value and the moving concentration value of the gas exceeds the second threshold value. According to this aspect, since the reference for the amount of change is the moving average value, it is possible to specify the start of specifying the breath component using the relative value. Therefore, the components of exhaled breath can be measured at a place where the atmospheric pressure is different or a place where the gas environment is different, and convenience can be improved.

In the above-mentioned aspect, it is preferable to provide a blowing attachment that can be attached to the inflow port of the case and has a pipe line for guiding exhaled air blown by a person to the channel pipe. By using the attachment for blowing, the thickness of the exhalation component measuring device in a state in which it is removed can be reduced and easily carried. As a result, the convenience of the breath component measuring device can be improved.
In the above-described aspect, it is preferable that the inner diameter of the pipe line is 4 mm and the inner diameter of the flow path pipe is 6 mm.

(A) is a front view of the breath component measuring apparatus main body which comprises the breath component measuring apparatus of one Embodiment of this invention, (B) is the back view. It is AA sectional drawing of the breath component measuring device main part of Drawing 1 (A). It is a front view which shows the expiration component measuring device main body which abbreviate | omitted the front case and lid | cover of FIG. It is an expanded sectional view of the part of the channel of Drawing 2. (A) The rear view of the flow-path pipe | tube of this embodiment, (B) is a right view of the flow-path pipe of this embodiment, (C) is a top view of the flow-path pipe of this embodiment. (A) is a perspective view of the gas sensor of this embodiment, (B) is sectional drawing of the gas sensor of this embodiment. It is a graph which shows the time change of a gas sensor output when a pipe line internal diameter is 4 mm and a flow path pipe internal diameter is 3 mm. It is a graph which shows the time change of the gas sensor output when a pipe line internal diameter is 4 mm and a flow path pipe internal diameter is 4 mm. It is a graph which shows the time change of the gas sensor output when a pipe line internal diameter is 4 mm and a flow path pipe internal diameter is 5 mm. It is a graph which shows the time change of a gas sensor output when a pipe line internal diameter is 4 mm and a flow path pipe internal diameter is 6 mm. It is a graph which shows the time change of the gas sensor output in case a pipe line internal diameter is 4 mm and a flow path pipe internal diameter is 10 mm. It is a graph of pressure sensor output value Vp [V] with respect to time at the time of performing 1 ppm acetone gas blowing in this embodiment. It is a graph of pressure sensor output value Vp [V] with respect to time at the time of performing 1 ppm acetone gas injection in the form compared. It is a functional block diagram of the breath component measuring device main body of this embodiment. FIG. 15 is an operation flow of the breath component measuring apparatus. It is a graph which shows an example of a change of pressure and a change of concentration of gas. 10 is an enlarged cross-sectional view of a flow path portion of Modification 1. FIG. 10 is an enlarged cross-sectional view of a flow path portion of Modification 2. FIG. 10 is an enlarged cross-sectional view of a flow path portion of Modification 3. FIG.

Hereinafter, an exhalation component measuring apparatus according to an embodiment of the present invention will be described with reference to the drawings.
<First Embodiment>
<Exhalation component measuring device>
1A is a front view of a breath component measuring apparatus main body 1 constituting one embodiment of the present invention, FIG. 1B is a rear view of the breath component measuring apparatus main body 1, and FIG. 2 is shown in FIG. It is AA sectional drawing of an expiration component measuring device. The exhalation component measuring device includes an exhalation component measuring device body 1 and an attachment 6 for exhaling breath attached to the exhalation component measuring device body 1.

  In FIGS. 1A and 1B, the breath component measuring apparatus main body 1 is configured as a box-shaped case by a front case 2, a back case 3 and a lid 4. A lid 4 is detachably attached to the back case 3 so as to be accessible inside. The front case 2 is provided with an inflow port 2a for taking in exhalation inside. The cable 5 is used for connecting the breath component measuring apparatus main body 1 to the outside.

  As shown in FIG. 2, a blow attachment attachment hole 2 b is provided outside the inflow port 2 a of the front case 2. By fitting the cylindrical protrusion 6c of the exhalation blowing attachment 6 into the exhalation blowing attachment mounting hole 2b, the exhalation blowing attachment 6 is attached to the inflow port 2a of the exhalation component measuring device main body 1.

<Exhalation component measuring device body 1>
FIG. 3 is a front view of the breath component measuring apparatus main body 1 from which the front case 2 and the lid 4 are omitted. As shown in FIG. 3, the breath component measuring apparatus body 1 measures a gas other than the gas sensor unit 11, the pressure sensor 26, and the gas sensor 9, which are integrally formed with the flow path pipe 8, the gas sensor 9 and the gas sensor 9. A second gas sensor 17 for performing the operation, an air barrel 19 for introducing exhalation into the second gas sensor 17, and a solenoid 18 for moving the air barrel 19.

<Flow path>
FIG. 4 is an enlarged cross-sectional view of the flow path portion of FIG. As described above, the breath blowing attachment 6 is attached to the front case 2. The exhalation-blowing attachment 6 has therein a pipe line 6a for passing exhaled breath blown by a person and a straw attachment hole 6b. A straw 7 is attached to the straw attachment hole 6b. By attaching the breath blowing attachment 6 to the front case 2, the straw 7, the conduit 6 a, the inner surface of the protruding portion 6 c, the inlet 2 a, the inner surface 8 a of the channel tube 8, and the outlet 3 a of the rear case 3 communicate with each other. And let breath.

  Here, the part through which exhaled air from the pipe line 6a to the flow path pipe 8 passes is called a flow path. That is, in the present embodiment, a flow path for passing exhalation is formed by the duct 6a, the inner surface of the protrusion 6c, the inflow port 2a, and the inner face 8a of the channel pipe 8. At this time, the inner diameter of the channel tube 8 is larger than the inner diameter of the channel tube side end portion 6d of the channel 6a. The inner diameters of the inner surfaces of the inflow port 2a and the protruding portion 6c communicate with the flow channel pipe 8, and the inner diameters are configured to have the same size (the same cross-sectional shape). The inner diameter of the straw 7 is configured to be the same as the inner diameter of the pipe line 6a. By providing the straw attachment hole 6b and the straw 7, only the straw can be exchanged, and the frequency of exchanging the breath blowing attachment 6 can be lowered.

<Opening portion 8c and gas sensor mounting portion 8b>
FIGS. 5A to 5C are views of the channel tube 8 viewed from three directions. When the direction of the channel tube 8 of FIG. 3 is faced, FIG. (B) is a right side view, (C) is a plan view. As shown in FIGS. 4 and 5C, an opening 8 c for introducing the exhaled air in the flow channel 8 into the gas sensor 9 is provided on the inner surface 8 a of the flow channel 8. In addition, a gas sensor attachment portion 8b is provided on the side surface of the flow channel tube 8 (a direction perpendicular to the direction in which exhalation flows). Further, as shown in FIG. 5C, the gas sensor mounting portion 8b is cylindrical and is provided so as to surround the opening 8c in a plan view, and is provided so that the inside of the gas sensor mounting portion 8b and the opening 8c communicate with each other. It is done.
A guide portion 8 f is formed on the outer surface of the flow channel tube 8. On the other hand, as shown in FIG. 6A, the gas sensor 9 has an intake port for taking in exhaled air on a predetermined surface 9p. And the gas sensor 9 is attached so that the guide part 8f of the flow-path pipe 8 and the predetermined surface 9p may contact | adhere so that the intake port 9b may be located inside the opening part 8c. In this example, since the predetermined surface 9p is a flat surface, the guide portion 8f is also a flat surface. However, when the predetermined surface 9p is a curved surface, the guide portion 8f is a curved surface along the predetermined surface 9p. ing.
Thus, since the guide part 8f of the flow path pipe 8 and the predetermined surface 9p of the gas sensor 9 are in close contact,
Since the gas sensor 9 can reliably capture the exhaled gas flowing through the flow path pipe 8 without going through the exhaled gas accumulation space, the output response of the gas sensor 9 can be improved.

<Gas sensor 9>
As shown in FIG. 4, the gas sensor 9 is inserted and attached to the inner surface of the gas sensor attachment portion 8b. The gas sensor 9 is incorporated in the gas sensor unit 11 together with the gas sensor substrate 10. As shown in FIG. 3, the gas sensor unit 11 includes a connector 21 for connection to the gas sensor 9 and the main board 14 at the bottom, and is removable from the breath component measuring apparatus main body 1. A partition plate 13 is provided between the gas sensor unit 11 and the front case 2. The partition plate 13 in this example is a part of the back case 3 and is integrally formed.

  6A is a perspective view of the gas sensor 9, and FIG. 6B is a cross-sectional view thereof. In the gas sensor 9, terminals 9d, 9e, and 9f for supplying electricity for detection and heating of the resistance value of the gas sensor element 9g are attached to the resin base 9c, and an intake port 9b is provided above the cover 9a. Although the intake port 9b has been shown as an example of six small holes, it may have any shape as long as gas (exhalation) can be taken in, for example, even if the intake port 9b is constituted by one larger hole. Good.

  The gas sensor 9 is installed in the main body by being inserted into the gas sensor mounting portion 8b while the intake port 9b faces downward (the intake port 9b faces the opening 8c). Here, the position of the intake port 9b is attached so that the intake port 9b is exposed when viewed from the inner surface 8a of the flow channel tube 8.

  The expiratory flow rate will be described. When exhalation is blown into the straw by a person, the straw 7, the conduit 6a, the inner surface of the protruding portion 6c, the inlet 2a, the inner surface 8a of the channel tube 8, and the outlet 3a of the rear case 3 communicate with each other. Expiration passes through these. At this time, the inner diameter of the channel tube 8 is larger than the inner diameter of the channel tube side end 6d of the channel 6a. For this reason, in the region 50 (indicated by a broken line in FIG. 4) in the channel tube 8, it is assumed that the channel 6 a is extended from the channel tube side end 6 d in the length direction of the channel tube 8. Since the exhaled air blown from the pipe line 6 a goes straight, the flow velocity becomes faster than the area other than the area 50. On the other hand, in regions other than the region 50, that is, outside the inside of the flow channel tube 8, the flow rate of exhalation is slower than the center side. Since the opening 8c provided in the inner surface 8a of the flow channel pipe 8 is a region other than the region 50, the exhaled air decelerated from the flow velocity of the pipe line 6a passes through the opening 8c and reaches the gas sensor 9. The gas sensor 9 measures the concentration of a predetermined gas in exhaled breath.

  Thus, since the inner diameter of the flow path pipe 8 is configured to be larger than the inner diameter of the flow path pipe side end portion 6d of the pipe path 6a, the pipe path 6a is connected from the flow path pipe side end portion 6d to the inside of the flow path pipe 8. The exhaled breath in the area other than the area 50 assumed to be extended becomes slow. Since the opening 8c is provided in the inner surface 8a of the flow path tube 8 which is a region where the flow velocity becomes slow and the gas sensor 9 is disposed in the vicinity of the discharge port 3a, the expiration that reaches the gas sensor 9 is decelerated. Can be prevented from becoming unstable. Further, since the exhaled gas inside the flow channel pipe 8 quickly reaches the gas sensor 9 without passing through the air reservoir or the like, the output response of the gas sensor 9 can be improved.

  In this embodiment, since the opening 8c and the gas sensor 9 are provided on the upper side of the flow channel tube 8, water droplets due to saliva or condensation are unlikely to accumulate in the gas sensor 9, and the malfunction of the gas sensor 9 due to saliva or condensation is suppressed. it can.

<Experimental data on flow path pipe inner diameter>
FIGS. 7 to 11 are graphs showing changes over time in the gas sensor output value Vs when the inner diameter φ of the flow channel tube 8 in FIG. 4 is changed to 3 mm, 4 mm, 5 mm, 6 mm, and 10 mm, respectively. In any graph, the inner diameter of the flow pipe side end 6d of the attachment 6 for exhalation is fixed to 4 mm, the gas to be injected is 1 ppm of acetone, and the flow rate of the gas to be injected into the pipe 6a is 30 l / The case of min (liter / minute) is indicated by a solid line, the case of a flow rate of 40 l / min is indicated by a broken line, and the case of a flow rate of 50 l / min is indicated by a dotted line. In the experiment, exhalation was stopped about 20 seconds after the start of measurement.

  Here, the higher the gas concentration, the higher the gas sensor output value Vs. In the graphs of FIGS. 7 to 11, the vertical axis represents the gas sensor output value Vs [V], and the horizontal axis represents the time sec (seconds) elapsed from the start of blowing. In this experiment, the inner diameters of the inflow port 2a and the protruding portion 6c in FIG. 4 were the same as the inner diameter of the inner surface 8a of the flow channel tube 8 (the cross-sectional shapes thereof were made to be the same shape and communicated).

  As shown in FIG. 7, when the inner diameter φ of the flow path tube 8 is 3 mm, the variation in the gas sensor output value Vs is small with respect to the change in the gas flow rate. However, the gas sensor output value Vs during measurement decreases until about 13 seconds from the start of gas blowing, and then increases. That is, the gas sensor output value Vs does not increase corresponding to the change in the amount of gas blown in as time passes, and is not appropriate for use in the breath component measuring apparatus.

  As shown in FIG. 8, when the inner diameter φ of the flow channel tube 8 is 4 mm, the gas sensor output value Vs increases corresponding to the change in the amount of gas blow-in if the gas flow rate is 30 l / min. However, when the gas flow rate is 40 l / min and 50 l / min, the gas sensor output value Vs does not increase corresponding to the change in the amount of gas blown in with the passage of time. That is, when the inner diameter φ of the channel tube 8 is 4 mm, there are a mixture of cases where the gas sensor output value Vs corresponding to the change in the amount of gas blown is obtained and those where the gas sensor output value Vs cannot be obtained. When the inner diameter φ of the flow channel tube 8 is 4 mm, the variation in the gas sensor output value Vs corresponding to the gas flow rate is large, so that it is not suitable for use in the breath component measuring apparatus.

  On the other hand, as shown in FIGS. 9 to 11, when the inner diameter φ of the channel tube 8 is 5 mm to 10 mm, the gas sensor output value Vs increases corresponding to the change in the amount of gas blown. Further, the variation of the gas sensor output value Vs according to the gas flow rate is also within an allowable range. Therefore, it is preferable to use these for the breath component measuring apparatus. In this way, it is confirmed that it is preferable to configure the inner diameter of the flow path pipe 8 to be larger than the inner diameter of the flow path pipe side end portion 6d of the pipe path 6a from the viewpoint of obtaining a stable gas sensor output value Vs. It was.

  As shown in FIG. 4, in the region 50 in which the conduit 6 a is assumed to be extended from the end 6 d of the channel tube inside the channel tube 8, the expiratory flow rate is faster than the flow rate outside the channel tube 8. . As described above, when the inner diameter of the flow channel 8 is larger than the inner diameter of the pipe 6 a, the opening 8 c can be formed outside the region 50. As a result, the gas sensor 9 can be arranged at a location where the exhaled gas flows gently, so that the exhaled gas is reliably taken into the gas sensor 9 and stable measurement can be performed.

In the above experiment, when the inner diameter φ of the pipe line 6a is 4 mm, the inner diameter φ of the flow path pipe 8 is changed in the range of 3 mm to 10 mm, and the inner diameter φ of the flow path pipe 8 is preferably in the range of 5 mm to 10 mm. Was obtained. If the ratio of the inner diameter φ of the conduit 6a and the inner diameter φ of the channel tube 8 is constant, the flow rate of the breath inside the channel tube 8 is distributed in the same way. Therefore, if the inner diameter φ of the channel pipe 8 is in the range of about 1.2 times to about 2.5 times the inner diameter φ of the pipe line 6a, the output value of the gas sensor 9 can be stabilized, and the exhalation component It is suitable for use in a measuring device.
In particular, when the inner diameter φ of the pipe 6a is 4 mm and the inner diameter φ of the flow pipe 8 is 6 mm (1.5 times the inner diameter of the pipe 6a), the variation in the gas sensor output value Vs according to the gas flow rate is the smallest. Therefore, it is suitable for use in the breath component measuring apparatus.

<About the range of the inner diameter of the flow path>
In the expiratory component measuring device, assuming that the inner diameter of the flow passage tube 8 is larger than the inner diameter of the conduit 6a, the inner diameters of the pipe passage 6a and the flow passage tube 8 in the flow passage through which exhalation passes are 4 mm in any part. The thickness is preferably less than 10 mm.

  Since the maximum inner diameter of the pipe 6a and the flow pipe 8 in the flow path is reduced to less than 10 mm, it is possible to measure the exhalation component without requiring a flow rate even if the force of blowing human exhalation is weak. Expiratory gas can reach, and expiratory component measurement can be suitably performed. In particular, it is possible to measure exhalation components even for a woman who is weak in breathing, such as an elderly woman. However, in the case where the inner diameter of the flow path is less than 4 mm, the flow rate is too fast with the force of blowing human exhalation, so that the gas sensor 9 may not be able to catch the exhalation, which is not suitable. These things were confirmed by conducting experiments by measuring the breath components by many people. The inner diameter of the protrusion 6c of the attachment 6 for exhalation and the inner diameter of the inflow port 2a are not necessarily less than 10 mm.

<Introduction pipe>
In FIG. 5C, the first introduction pipe 8d transmits the pressure inside the flow path pipe 8 to the pressure sensor 26, and the second introduction pipe 8e passes through the second gas sensor to be described later. It connects with the pipe 28 for letting exhalation pass. The second introduction pipe 8e has a hole 8i inside. As shown in FIG. 3, the first introduction pipe 8 d is connected to the pressure transmission pipe 27, and the pressure transmission pipe 27 is connected to the input port of the pressure sensor 26. Further, as shown in FIG. 5C, the first introduction pipe 8d is attached so as to penetrate the flow path pipe 8, and the hole 8g is provided so as to communicate from the inside of the flow path pipe 8 to the outside. . The pressure transmission pipe 27 is connected by fitting the end of the first introduction pipe 8d on the pressure sensor 26 side. Further, the channel tube side end portion 8h of the first introduction tube 8d protrudes to the inside of the channel tube 8 and is provided at a position included in the region 50 shown in FIG.

  When exhalation is blown into the flow channel tube 8, pressure is generated at the flow channel side end portion 8h of the first introduction tube 8d, and the pressure is passed through the hole 8g of the first introduction tube 8d via the pressure transmission tube 27. Is transmitted to the pressure sensor 26. The pressure sensor 26 detects the pressure generated at the channel tube side end 8h. When the amount of change in the output value of the pressure sensor 26 exceeds the first threshold value ref1, it is determined that exhaled air has flowed into the flow channel pipe 8, and the output value of the gas sensor 9 is referred to (step of FIG. 14 described later) (See S3).

  As described above, in the region 50 in which it is assumed that the conduit 6a is extended from the end 6d of the channel tube inside the channel tube 8 shown in FIG. 4, the expiratory flow rate is faster than the flow rate outside the channel. Become. That is, in the flow path pipe 8, the flow speed is faster and the pressure change is larger on the inner side than the vicinity of the inner surface 8a. Since the channel pipe side end portion 8h of the first introduction pipe 8d is protruded inward so as to be in a position included in the region 50, the pressure at a place where the pressure change is particularly large can be transmitted to the pressure sensor 26. it can. Therefore, the pressure sensor 26 can detect a pressure change sensitively, and can quickly detect exhalation.

  FIG. 12 shows that the channel tube side end portion 8h of the first introduction tube 8d in the present embodiment protrudes inward so as to be included in the region 50. It is a graph of the pressure sensor output value Vp [V] with respect to time when 1 ppm of acetone gas was blown at 40 l / min (liter / minute) during the period. For comparison with the graph of FIG. 12, FIG. 13 shows the flow channel tube 8 when the hole 8g is provided in the inner surface 8a without projecting the flow channel side end portion 8h of the first introduction tube 8d inward. 6 is a graph of the pressure sensor output value Vs [V] with respect to time when the same concentration of acetone gas is blown at the same flow rate at the same time. The pressure sensor output value Vp is 2V in a steady state, and is a value lower than 2V when negative pressure is applied. The pressure sensor output value Vp is 1.2 times larger in the case of FIG. For this reason, it has been confirmed that the output value of the pressure sensor 26 is increased when the end portion 8h of the flow channel side in FIG. 12 is protruded inward.

<Operation of the breath component measuring apparatus>
FIG. 14 is an example of a functional block diagram of the breath component measuring apparatus main body 1. The same reference numerals are used for the same components as in FIG. The control unit 40 is an arithmetic module including an arithmetic device such as a CPU (not shown), a storage device such as a memory, and other electronic circuit hardware and software such as a program. The control unit 40 also includes a gas sensor 9 that measures the gas concentration in the flow channel tube 8 and a pressure sensor 26 that measures the pressure inside the flow channel tube 8 through the pressure transmission tube 27 in order to detect that exhalation has been blown. , And a second gas sensor 17 for measuring through a pipe 28 described later, and controls these operations. The control unit 40 has an output IF 51 (interface) for outputting measurement results to an external personal computer, display, speaker, printer, or the like, and setting information from the outside by a personal computer or operation buttons to the control unit 40. And so on.

  The control unit 40 includes an operation control unit 41 that controls each element and module, a pressure data generation unit 42 that AD-converts an output signal of the pressure sensor 26 and generates pressure data indicating an output value of the pressure sensor 26, and An exhalation blowing determination unit 43 that determines whether exhalation has flowed in with reference to a measurement result of the pressure data generation unit 42, and AD gas-converted output signals from the gas sensor 9 to generate first gas data indicating an output value of the gas sensor 9. Generated by the first gas data generation unit 44, the result determination unit 45 that determines the result of how to evaluate exhalation based on the measurement results of the first gas data generation unit 44, and the first gas data generation unit 44 An output stability determination unit 46 for determining whether the output of the gas sensor 9 is in a stable state based on the first gas data, a gas sensor output value threshold value determination for determining whether to take in the gas sensor output value 47, a second gas data generation unit 48 that AD converts the output signal of the second gas sensor 17 to generate second gas data indicating the output value of the second gas sensor 17, and a determination result calculated by the result determination unit 45 And a display information generation unit 49 for determining how to display the function as a function module.

<Operation flow>
FIG. 15 is an example of an operation flow of the breath component measuring apparatus. In this operation flow, on the condition that the change amount of the pressure detected by the pressure sensor 26 exceeds the first threshold value ref1, and the change amount of the gas concentration detected by the gas sensor 9 exceeds the second threshold value ref2. Start identifying components of exhaled breath. FIG. 16 illustrates a change in pressure detected by the pressure sensor 26 and a change in gas concentration detected by the gas sensor 9.

  First, the expiration component measuring device determines whether the output of the gas sensor 9 is stable (step S1). That is, the output stability determination unit 46 determines whether the output of the gas sensor 9 is stable based on the first gas data indicating the output value of the gas sensor 9. If the output stability determination unit 46 determines that the output of the gas sensor 9 is stable, it sends a determination result that the output is stable to the operation control unit 41 (in the case of Yes in step S1). When it is determined that the output of the output stability determination unit 46 is not stable, the operation control unit 41 does not start measurement preparation and waits for the output of the gas sensor 9 to be stable (in the case of No in step S1). .

  Next, the operation control unit 41 that has received the result that the output of the gas sensor 9 is stable completes the preparation of the expiration component measurement, and the control unit 40 enters a state of receiving the output signal of the pressure sensor 26 (step S2). ). In this case, the control unit 40 outputs instruction information for prompting to blow exhalation to the display unit (not shown) via the output IF 51 when a predetermined time has elapsed since the output signal of the pressure sensor 26 is received. Alternatively, the breath component measuring apparatus main body 1 may be provided with a display unit for display. In this case, the display unit may turn on an LED of a predetermined color according to the instruction information.

  Next, the exhalation component measuring device determines whether or not the pressure sensor 26 has detected the pressure due to the exhalation of the exhalation in the flow channel tube 8 (step S3). The exhalation blowing determination unit 43 always calculates the moving average value avr1 of the pressure value based on the pressure data indicating the output value of the pressure sensor 26. More specifically, the moving average value avr1 is calculated for a predetermined number of pressure data in the past from the current pressure data. If the pressure data changes in the order of Dp1, Dp2, Dp3, Dp4, Dp5, Dp6, the current pressure data is Dp6, and the predetermined number is “5”, the moving average value avr1 is avr1 = ( Dp1 + Dp2 + Dp3 + Dp4 + Dp5) / 5. The exhalation blowing determination unit 43 calculates a difference between the current pressure data Dp6 and the moving average value avr1 of the pressure data as a change amount of the output value of the pressure sensor 26, and determines whether or not the change amount exceeds the first threshold value ref1. judge.

  When exhaled air is blown, a pressure is generated inside the flow channel tube 8, and the pressure is transmitted to the pressure sensor 26 via the pressure transmission tube 27 through the hole 8g of the first introduction tube 8d. The first threshold value ref1 is determined so that it can be determined whether or not the pressure change generated in the flow channel tube 8 is due to the blowing of exhaled air. Also, instead of comparing the absolute value of the pressure with the first threshold value ref1, the amount of change in the pressure and the first threshold value ref1 are compared. It becomes possible to detect.

For example, in the example shown in FIG. 16, exhalation starts from time t0. When exhalation starts, the output of the pressure sensor 26 becomes negative pressure. The difference between the moving average value avr1 serving as the amount of change at this time and the current output value exceeds the first threshold value ref1 at time t1. Therefore, in the example shown in FIG. 16, the expiration inhalation determination unit 43 determines that the pressure sensor 26 has detected the pressure due to the expiration inhalation when time t1 is reached.
When it is determined that exhalation has been blown, the exhalation blowing determination unit 43 sends the result of the determination to the operation control unit 41 (in the case of Yes in step S3). When the exhalation blowing determination unit 43 does not detect the exhalation, the pressure data indicating the output value of the pressure sensor 26 is continuously received (in the case of No in step S3).

Next, the exhalation component measuring device determines whether or not the gas sensor 9 detects the gas concentration by inhaling exhalation (step S4). The gas sensor output value threshold value determination unit 47 reads the first gas data output from the first gas data generation unit 44.
The gas sensor output value threshold determination unit 47 always calculates the moving average value of the first gas data. More specifically, the moving average value avr2 is calculated for a predetermined number of past first gas data from the current first gas data. If the first gas data changes in the order of Dg1, Dg2, Dg3, Dg4, Dg5, Dg6, the current first gas data is Dg6, and the predetermined number is “5”, the moving average value avr2 is , Avr2 = (Dg1 + Dg2 + Dg3 + Dg4 + Dg5) / 5. The exhalation blowing determination unit 43 calculates the difference between the current first gas data Dg6 and the moving average value avr2 of the first gas data as the change amount of the output value of the gas sensor 9, and whether the change amount exceeds the second threshold value ref2. Determine whether or not.
The second threshold value ref2 is determined so that it can be determined whether or not the gas concentration change generated in the flow channel tube 8 is due to the inhalation of exhaled air. Also, since the absolute value of the first gas data is not compared with the second threshold value ref2, the amount of change in the first gas data is compared with the second threshold value ref2, so that exhalation is possible even when measured in various environments. It becomes possible to reliably detect the concentration of gas due to the blowing of gas.
For example, in the example shown in FIG. 16, the difference between the moving average value avr2 that is the amount of change in the output value of the gas sensor 9 and the current first gas data exceeds the second threshold value ref2 at time t2. Therefore, in the example shown in FIG. 16, the expiration inhalation determination unit 43 determines that the gas sensor 9 has detected that the gas concentration has changed due to the expiration inhalation when time t2 is reached.

  If the gas sensor output value threshold value determination unit 47 determines that the amount of change in the output value of the gas sensor 9 has exceeded the second threshold value ref2, it sends the determination result to the operation control unit 41 (Yes in step S4). If the change amount of the output value of the gas sensor 9 does not exceed the second threshold value ref2, the gas sensor output value threshold value determination unit 47 determines that the output data of the first gas data generation unit 44 is not taken in, and remains as it is. Wait until the amount of change in the first gas data exceeds the second threshold value ref2 (No in step S4).

Next, the result determination unit 45 takes in the first gas data indicating the output value of the gas sensor 9 (step S5). Next, the result determination unit 45 specifies a gas concentration value based on the output data of the first gas data generation unit 44 (step S6). Specifically, the result determination unit 45 specifies the time t0 when the inhalation starts from the change in the output data of the first gas data generation unit 44. Next, the result determination unit 45 specifies the time t3 when the predetermined time Tx has elapsed from the time t0. The output value of the gas sensor 9 has a characteristic of gradually increasing from the start of exhalation and converges to a steady value Z as shown in FIG. What is to be calculated is the gas concentration value Y corresponding to the steady value Z. The output value of the gas sensor 9 corresponds to the gas concentration value, but the output value of the gas sensor 9 is a voltage value of an output signal to the gas sensor 9 and is not the gas concentration value itself.
The transient response characteristic of the output value of the gas sensor 9 is known. Therefore, the gas concentration value Y (a value corresponding to the steady value X) is specified from the output value X of the gas sensor 9 when the predetermined time Tx has elapsed since the start of blowing.
The result determination unit 45 calculates the gas concentration value Y using an arithmetic expression having the output value X as a variable. Alternatively, the result determination unit 45 includes a gas concentration table in which the output value X and the gas concentration value Y are stored in association with each other, and the first gas data generation unit 44 at time t3 when a predetermined time Tx has elapsed from the start of blowing. May be acquired as an output value X, and a gas concentration value Y corresponding to the output value X may be read out by referring to a gas concentration table.

  Next, the expired air component measurement device displays the gas concentration value Y detected by the gas sensor 9 (step S7). That is, based on the content of the measurement result such as the gas concentration value Y determined by the result determination unit 45 in step S6, the display information generation unit 49 generates display information and displays the display information on the display or the like through the output IF 51. Display on the device.

  As described above, in the present embodiment, the amount of change in pressure detected by the pressure sensor 26 exceeds the first threshold ref1, and the amount of change in gas concentration detected by the gas sensor 9 exceeds the second threshold ref2. As a result, identification of the component of exhalation was started. Since the two elements such as the pressure and the gas concentration are used as the condition for starting the expiration component, the expiration measurement can be performed more quickly than when only the pressure is used as the condition for starting the expiration component. If only pressure is a condition, it is necessary to increase the first threshold value ref1 because it is necessary to determine the expiration of breathing with one element. On the other hand, in this embodiment, since not only the pressure but also the gas concentration is used as the determination condition, the first threshold value ref1 can be lowered. As a result, it is possible to quickly measure expiration. Older people may have difficulty breathing in for a long time. In the present embodiment, the expiration time for exhalation can be shortened, so that the convenience of a subject who is weak in exhalation, such as an elderly person, can be improved.

<Second gas sensor>
In the above-described flow, the case where the gas concentration is measured only by the gas sensor 9 has been described. However, in the result determination in step S5, the result may be derived with reference to the measurement result of the second gas sensor 17. As shown in FIG. 3, the second gas sensor 17 is attached to a plate 16 supported by a vertical plate 15 provided on the main substrate 14, and the second gas sensor 17 and the inside of the flow path pipe 8 are the second introduction. It is connected by a pipe 28 via a pipe 8e (see FIGS. 5A to 5C). The second gas sensor 17 and the air barrel 19 for drawing air are connected by a pipe 30. In this configuration, the operation control unit 41 operates the solenoid 18 for moving the air barrel 19. Next, the air barrel 19 draws gas, whereby the exhaled gas in the flow path pipe 8 is introduced into the second gas sensor 17, and the second gas sensor 17 can measure the concentration of the gas component contained in the exhaled gas. When the second gas sensor 17 is used, for example, the gas sensor 9 can be a gas sensor that reacts with the ethanol concentration and the acetone concentration contained in exhaled breath, and the second gas sensor 17 can be a sensor that measures the ethanol concentration. Then, the result determination unit 45 can calculate the acetone concentration value by calculating the difference between the ethanol concentration value measured by the second gas sensor 17 from the ethanol and acetone concentration values measured by the gas sensor 9. It is known that acetone is generated when fat is burned in the human body, so it is known that the concentration of acetone in the breath increases, and measuring the acetone concentration is useful as a measure of whether the diet is successful. . As described in the example of measuring the gas concentration only by the gas sensor 9 in the above flow, the second gas sensor 17, the air barrel 19 and the solenoid 18 are not essential.

<Modification 1>
You may comprise a flow path as shown in FIG. In the modification of FIG. 17, the same reference numerals are used for elements having the same functions as those in FIG. In FIG. 17, the inner diameter of the pipe line 6a of the attachment for exhalation 6 is A, the inner diameter of the projecting portion 6c of the attachment 6 for exhalation is B, the inner diameter of the inlet 2a is C, and the inner diameter of the channel pipe 8 is This will be described as D. In the first modification, the inner diameter B of the projection 6c of the attachment 6 for inhalation of breath and the inner diameter C of the inflow port 2a are larger than the inner diameter of the channel pipe 8 in comparison with the embodiment of FIG. It is composed.

  Even in such a configuration, the region 50 that is assumed to extend the conduit 6 a from the flow channel side end 6 d of the conduit 6 a of the breath blowing attachment 6 to the flow channel 8 side is other than the region 50. Compared to the region 50, the flow velocity is faster than that in the region 50, and the flow velocity is slower in the regions other than the region 50 than in the region 50. Therefore, an effect equivalent to that of the embodiment shown in FIG. 4 is obtained.

<Modification 2>
You may comprise a flow path as shown in FIG. In the modified example 2 of FIG. 18, elements having the same functions as those in FIG. In this modified example, the inner diameter of the protrusion 6c is the same as that of the conduit 6a of the exhalation-injection attachment 6, and the flow channel side end 6d of the conduit 6a of the exhalation-injection attachment 6 is connected to the inlet 2a. Has reached.

  Even in such a configuration, the region 50 assumed that the conduit 6 a is extended from the flow channel side end 6 d of the conduit 6 a of the breath blowing attachment 6 to the flow channel 8 side is other than the region 50. Compared to the region 50, the flow velocity is faster than that in the region 50, and the flow velocity is slower in the regions other than the region 50 than in the region 50. Therefore, an effect equivalent to that of the above-described embodiment can be obtained.

  Although not shown, the inner diameter C of the inflow port 2a in FIG. 18 may be configured to be the same size as the inner diameter of the conduit 6a of the exhalation-blowing attachment 6. Even in such a configuration, the region 50 assumed that the conduit 6 a is extended from the flow channel side end 6 d of the conduit 6 a of the breath blowing attachment 6 to the flow channel 8 side is other than the region 50. Compared to the region 50, the flow velocity is faster than that in the region 50, and the flow velocity is slower in the regions other than the region 50 than in the region 50. Therefore, an equivalent effect can be obtained.

<Modification 3>
You may comprise a flow path as shown in FIG. In Modification 3 of FIG. 19, elements having the same functions as those in FIGS. 17 and 18 are denoted by the same reference numerals and description thereof is omitted. In FIG. 19, the exhalation-injection attachment 6 is fitted into the inflow port 2a, the exhalation-injection attachment 6 is in contact with the channel tube 8, and the channel tube side end 6d of the channel 6a flows. It is in contact with the end portion of the pipe 8 attached to the breath blowing attachment.

  Even in such a configuration, the region 50 assumed that the conduit 6 a is extended from the flow channel side end 6 d of the conduit 6 a of the breath blowing attachment 6 to the flow channel 8 side is other than the region 50. Compared to the region 50, the flow velocity is faster than that in the region 50, and the flow velocity is slower in the regions other than the region 50 than in the region 50. Therefore, an effect equivalent to that of the above-described embodiment can be obtained.

  In these embodiments, the example in which the straw attachment hole 6b is provided with the straw attachment hole 6b and the straw is attached is shown in the embodiments, but the breath attachment attachment 6 is not provided without providing the straw attachment hole 6b. May be used as a mouthpiece.

  Moreover, although the breath component measuring device main body of this embodiment was demonstrated as what detects acetone, it can be used also in an alcohol sensor. Other modifications can be made without departing from the spirit of the present invention.

<Modification 4>
In the above-described embodiment, as described with reference to FIG. 15, after determining that the amount of change in pressure detected by the pressure sensor 26 has exceeded the first threshold value ref1, the gas detected by the gas sensor 9 is detected. Although it has been determined that the amount of change in density exceeds the second threshold ref2, the present invention is not limited to the determination order of two elements. That is, after determining that the change amount of the gas concentration detected by the gas sensor 9 exceeds the second threshold value ref2, it is determined that the change amount of the pressure detected by the pressure sensor 26 exceeds the first threshold value ref1. May be.

DESCRIPTION OF SYMBOLS 1 ... Exhalation component measuring apparatus, 2 ... Front case, 3 ... Back case, 4 ... Cover, 2a ... Inlet, 2b ... Attachment attachment hole for exhalation blowing, 3a ... Exhaust opening, 6 ... Attachment for exhalation blowing, 6a ... Pipe line, 6b ... Straw mounting hole, 6c ... Projection part, 6d ... Channel pipe side end, 7 ... Straw, 8 ... Channel pipe, 8a ... Inner surface, 8b ... Gas sensor mounting part, 8c ... Opening part, 8d DESCRIPTION OF SYMBOLS ... 1st introduction pipe, 8e ... 2nd introduction pipe, 8f ... Projection part, 8h ... Channel pipe side edge part, 9 ... Gas sensor, 9b ... Gas intake port, 9g ... Gas sensor element, 14 ... Main board, DESCRIPTION OF SYMBOLS 16 ... Plate, 17 ... 2nd gas sensor, 18 ... Solenoid, 19 ... Air barrel, 26 ... Pressure sensor, 27 ... Pressure transmission pipe, 40 ... Control part, 50 ... Area | region.

Claims (8)

A channel tube for passing exhaled air;
A gas sensor for detecting the concentration of gas contained in exhaled breath passing through the flow path tube;
A case containing the flow path pipe and the gas sensor;
Formed in the case so as to communicate with the flow channel pipe, and an inflow port for introducing exhalation from the outside of the case,
The flow channel tube forms a flow channel through which exhalation passes when an attachment for blowing having a conduit for guiding exhaled breath blown by a person is attached to the inflow port, and has an inner diameter larger than an inner diameter of the conduit ,
An expiratory component measuring device. The exhalation component measuring apparatus according to claim 1,
The channel pipe has an opening formed on the inner surface for introducing the exhaled gas inside the channel pipe to the gas sensor.
The gas sensor
An intake port for taking in exhalation is formed on a predetermined surface,
The guide port formed on the outer surface of the flow channel tube and the predetermined surface are attached to the flow channel tube so that the intake port is located inside the opening,
An expiratory component measuring device. In the breath component measuring apparatus according to claim 1 or 2,
The inner diameter of the channel pipe is 1.2 times or more and 2.5 times or less than the inner diameter of the pipe line.
An expiratory component measuring device. In the exhalation component measuring device according to any one of claims 1 to 3,
A pressure sensor for detecting the pressure in the flow path pipe;
A pressure transmission pipe connecting the inside of the flow path pipe and the pressure sensor in order to transmit the pressure in the flow path pipe to the pressure sensor;
An introduction pipe provided in the flow path pipe for transmitting pressure to the pressure transmission pipe;
The flow pipe side end portion of the introduction pipe is included in a region assumed to extend the pipe in the length direction of the flow pipe in the flow pipe.
An expiratory component measuring device. In the breath component measuring device according to claim 4,
Exhalation component identification is started on the condition that the amount of change in pressure detected by the pressure sensor exceeds a first threshold and the amount of change in concentration of gas detected by the gas sensor exceeds a second threshold. With a control unit,
An expiratory component measuring device. The breath component measuring apparatus according to claim 5,
The controller is
Identifying the moving average value of the pressure, determining whether the difference between the pressure value of the current pressure and the moving average value of the pressure exceeds the first threshold;
Identifying a moving average value of the gas concentration, and determining whether a difference between the current gas concentration value and the moving average value of the gas concentration exceeds the second threshold;
An expiratory component measuring device. The exhalation component measuring device according to any one of claims 1 to 6,
Attached to the inflow port of the case, and provided with a blowing attachment having a pipe line for guiding exhaled breath blown by a person to the channel pipe.
An expiratory component measuring device. The exhalation component measuring apparatus according to claim 7,
The inner diameter of the pipe line is 4 mm,
The inner diameter of the channel tube is 6 mm.
An expiratory component measuring device.

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