Exhalation component measurement device and method for determining abnormality

Abstract

To assure that gas taken into an exhalation container is exhalation of a subject.SOLUTION: An exhalation component measurement device 10 includes: an exhalation container 20 having an introduction port 21a for introducing exhalation of a subject, the container containing exhalation introduced through the introduction port 21a; an exhalation flow passage 33 for introducing the exhalation blown out of the mouth of the subject into the introduction port 21a; a gas sensor 15 for measuring a predetermined component of the exhalation introduced into the exhalation container 20; and an abnormality determination unit 103 for determining whether there is an abnormality in the pressure of the blowing out of the exhalation in the exhalation flow passage 33 when the exhalation is introduced from the introduction port 21a to the exhalation container 20.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an exhaled breath component measuring device that measures predetermined components in the exhaled breath of a subject, and an abnormality determination method that determines whether or not there is an abnormality in the exhaled breath component measurement. [Background technology]

[0002] The exhaled breath component measuring device takes in the exhaled breath blown out of the subject's mouth into an exhaled breath storage section, and measures predetermined components contained in the exhaled breath taken into the exhaled breath storage section. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2018-87788 Summary of the Invention [Problem to be solved by the invention]

[0004] For this reason, the breath must be blown out of the subject's mouth with an appropriate pressure into the breath chamber. If the pressure of the breath blown out from the subject when the breath chamber takes in the breath from the subject is not appropriate, it is not guaranteed that the gas taken in by the breath chamber is the breath of the subject, and the components of the breath from the subject cannot be measured appropriately.

[0005] Therefore, an object of the present invention is to provide an exhaled breath component measuring device and an abnormality determination method that can ensure that the gas taken into the exhaled breath storage section is the exhaled breath of the subject. [Means for solving the problem]

[0006] An exhaled breath component measuring device according to one embodiment of the present invention is configured to include an exhaled breath storage section having an inlet for introducing the exhaled breath of a subject and storing the exhaled breath introduced through the inlet, an exhaled breath introduction section for introducing the exhaled breath blown out of the subject's mouth into the inlet, a component measuring section for measuring a predetermined component of the exhaled breath introduced into the exhaled breath storage section, and an abnormality determination section for determining whether or not there is an abnormality in the blowing pressure of the exhaled breath at the exhaled breath introduction section when the exhaled breath is introduced from the inlet to the exhaled breath storage section.

[0007] With this configuration, by determining whether or not there is an abnormality in the blowing pressure of the subject's breath when the breath is introduced into the breath collection section, it is possible to ensure that the breath taken into the breath collection section is the subject's breath.

[0008] In the above-mentioned exhaled breath component measuring device, the abnormality determination unit may include a pressure detection unit that detects the pressure inside the exhaled breath storage unit, and may determine whether or not there is an abnormality based on the pressure detected by the pressure detection.

[0009] With this configuration, it is possible to determine whether or not there is an abnormality in the blowing pressure by detecting the pressure inside the expiratory gas chamber.

[0010] The above-mentioned exhaled breath component measuring device may further include a negative pressure generating unit that generates negative pressure in the exhaled breath storage unit in order to introduce the exhaled breath into the exhaled breath storage unit, and the abnormality determination unit may determine whether or not there is an abnormality in the blowing pressure during the operation for generating negative pressure by the negative pressure generating unit.

[0011] With this configuration, it is possible to determine whether or not there is an abnormality in the blow-out pressure when the exhaled air is introduced into the exhaled air storage section by negative pressure.

[0012] In the above-mentioned exhaled breath component measuring device, the negative pressure generating unit may be provided with a volume changing unit for changing the volume of the exhaled breath storage unit, and the abnormality determining unit may determine that the abnormality exists if the change in pressure detected by the pressure detecting unit when the volume changing unit reduces the volume in preparation for generating the negative pressure is equal to or less than a first threshold value.

[0013] With this configuration, it is possible to determine whether there is an abnormality in the blowing pressure when the volume of the expiratory gas storage compartment is reduced in preparation for generating negative pressure to introduce the subject's exhaled gas into the expiratory gas storage compartment.

[0014] In the above-mentioned exhaled breath component measuring device, the negative pressure generating unit may be provided with a volume changing unit for changing the volume of the exhaled breath accommodating unit, and the abnormality determining unit may determine that the abnormality exists when the pressure detected by the pressure detecting unit becomes equal to or lower than a second threshold value after the volume changing unit reduces the volume in preparation for generating the negative pressure.

[0015] With this configuration, it is possible to determine whether or not there is an abnormality in the blowing pressure after the volume of the expiratory gas storage compartment is reduced in preparation for generating negative pressure to introduce the subject's exhaled gas into the expiratory gas storage compartment.

[0016] In the above-mentioned exhaled breath component measuring device, the negative pressure generating unit may be provided with a volume changing unit for changing the volume of the exhaled breath accommodating unit, and the abnormality determining unit may determine that an abnormality exists if the change in pressure detected by the pressure detecting unit when the volume changing unit increases the volume to generate the negative pressure is equal to or less than a third threshold value.

[0017] With this configuration, it is possible to determine whether or not there is an abnormality in the blowing pressure when the volume of the expiratory gas storage compartment is increased to generate negative pressure for introducing the subject's exhaled gas into the expiratory gas storage compartment.

[0018] In the above-mentioned exhaled breath component measuring device, the negative pressure generating unit may be provided with a volume changing unit for changing the volume of the exhaled breath accommodating unit, and the abnormality determining unit may determine that the abnormality exists when the pressure detected by the pressure detecting unit becomes equal to or lower than a fourth threshold value after the volume changing unit increases the volume to generate the negative pressure.

[0019] With this configuration, it is possible to determine whether or not there is an abnormality in the blowing pressure after the volume of the expiratory gas storage compartment is increased to generate negative pressure for introducing the subject's exhaled gas into the expiratory gas storage compartment.

[0020] The above-mentioned exhaled breath component measuring device may further include an exhaled breath inflow measuring unit that detects that the subject has inhaled, held their breath, and blown out the exhaled breath from the exhaled breath inlet unit in that order, and the abnormality determining unit may use the pressure when the breath is held as a reference pressure and determine whether or not there is an abnormality based on the blowing pressure from the reference pressure.

[0021] This configuration reduces the possibility of anomalies or inaccurate component measurements due to an inaccurate reference pressure.

[0022] An abnormality determination method according to one embodiment of the present invention is a method for determining whether or not there is an abnormality in exhaled breath component measurement, which measures predetermined components in exhaled breath stored in an exhaled breath storage section having an inlet for introducing the exhaled breath of a subject, and is configured to perform an abnormality determination by determining whether or not there is an abnormality in the exhaled breath blowing pressure at an exhaled breath introduction section that introduces the exhaled breath blown out of the subject's mouth into the introduction section when the exhaled breath is introduced from the introduction section into the exhaled breath storage section.

[0023] With this configuration, it is possible to ensure that the exhaled breath taken into the exhaled breath storage section is the exhaled breath of the subject by determining whether or not there is an abnormality in the blowing pressure of the exhaled breath from the subject when the exhaled breath is introduced into the exhaled breath storage section. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view showing the appearance of an exhaled breath component measuring device according to a first embodiment of the present invention. [Figure 2] FIG. 2(a) is a front view of the exhaled breath component measuring device according to the first embodiment of the present invention, FIG. 2(b) is a side view of the exhaled breath component measuring device according to the first embodiment of the present invention, and FIG. 2(c) is a top view of the exhaled breath component measuring device according to the first embodiment of the present invention. [Figure 3] FIG. 3 is a cross-sectional view of the exhaled breath component measuring device according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a block diagram showing the overall configuration of the exhaled breath component measuring device according to the first embodiment of the present invention. [Figure 5] FIG. 5 is a diagram showing functional blocks realized by the control unit according to the first embodiment of the present invention. [Figure 6] FIG. 6 is a graph showing an example of the output of the pressure sensor (pressure in the expiratory gas storage section) when there is no abnormality. [Figure 7] FIG. 7 is a graph showing an example of the output of the pressure sensor (pressure in the expiratory gas chamber) when there is an abnormality in the blowing out. [Figure 8A] FIG. 8A is a flowchart illustrating the operation of the exhaled breath component measuring device according to the first embodiment of the present invention. [Figure 8B] FIG. 8B is a flowchart illustrating the operation of the exhaled breath component measuring device according to the first embodiment of the present invention. [Figure 8C] FIG. 8C is a flowchart illustrating the operation of the exhaled breath component measuring device according to the first embodiment of the present invention. [Figure 9] FIG. 9 is a diagram illustrating an example of a situation in which the breath of the subject cannot be taken in due to an abnormality in the pressure in the breath chamber before the start of blowing. [Figure 10] FIG. 10 is a graph showing an example of the output (pressure in the expiratory gas storage section) of the pressure sensor according to the second embodiment of the present invention. [Figure 11] FIG. 11 is a flowchart illustrating the operation of the exhaled breath component measuring device according to the second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are examples of how the present invention can be implemented, and the present invention is not limited to the specific configurations described below. When implementing the present invention, specific configurations corresponding to the embodiments may be appropriately adopted.

[0026] First Embodiment Fig. 1 is a perspective view showing the appearance of an exhaled air component measuring device 10 according to a first embodiment of the present invention. Fig. 2(a) is a front view of the exhaled air component measuring device 10, Fig. 2(b) is a side view of the exhaled air component measuring device 10, and Fig. 2(c) is a top view of the exhaled air component measuring device 10. Fig. 3 is a cross-sectional view of the exhaled air component measuring device 10.

[0027] A mouthpiece 30 having an exhaled air flow path 33 through which exhaled air blown from the mouth of the subject passes is attached to the exhaled air component measuring device 10. The exhaled air component measuring device 10 is provided with a power switch 12, an input interface (input I / F) 13 such as an operation button, an attachment part 14 for attaching the mouthpiece 30, a protrusion 21 provided with an inlet 21a communicating with the exhaled air flow path 33, and a display part 11a such as an LCD (Liquid Crystal Display). The attachment part 14 is provided with a holder 19 for detachably holding the mouthpiece 30. The inlet 21a introduces the exhaled air of the subject into an exhaled air storage part 20 inside the exhaled air component measuring device 10. The exhaled air component measuring device 10 can be equipped with a built-in battery such as a dry cell, and can be carried by the subject.

[0028] The mouthpiece 30 has an inlet 31 through which the subject blows their exhaled breath, an outlet 32 ​​through which the exhaled breath is discharged, and an exhaled breath flow path 33 formed between the inlet 31 and the outlet 32. The exhaled breath flow path 33 has a through-hole 33a formed therein into which the protrusion 21 is fitted when the mouthpiece 30 is attached to the exhaled breath component measuring device 10. When the protrusion 21 is fitted into the through-hole 33a, the exhaled breath flow path 33 and the inlet 21a communicate with each other. The exhaled breath flow path 33 introduces the exhaled breath blown out of the subject's mouth into the inlet 21a, and corresponds to the exhaled breath inlet section.

[0029] The exhaled breath component measuring device 10 includes an exhaled breath storage section 20 having an inlet 21a, a gas sensor 15 that measures a predetermined component in the exhaled breath stored in the exhaled breath storage section 20, a pressure sensor 16 that detects the pressure inside the exhaled breath storage section 20, a solenoid 18 that changes the volume of the exhaled breath storage section 20, and a control section 100 that controls the exhaled breath component measuring device 10. In this embodiment, alcohol is used as the predetermined component.

[0030] The exhaled breath accommodating section 20 includes a gas sensor chamber 15a in which the gas sensor 15 is provided, an air barrel 17 which is an expandable and contractible container, a flow path 22 which connects the inlet 21a and the gas sensor chamber 15a, a flow path 23 which connects the gas sensor chamber 15a and the air barrel 17, and a flow path 24 which connects the air barrel 17 and the pressure sensor 16.

[0031] The solenoid 18 is connected to the air barrel 17. When the solenoid 18 receives a solenoid control signal (described later), it expands, pushing the air barrel 17 and contracting it (reducing its volume). When the solenoid control signal is released, the solenoid 18 contracts, pulling the air barrel 17 back and expanding it (increasing its volume). The solenoid 18 contracts and then expands the air barrel 17, thereby drawing the subject's exhaled breath into the exhaled breath chamber 20 (particularly the gas sensor chamber 15a) through the inlet 21a. The volume of the exhaled breath chamber 20 is changed by the contraction and expansion of the air barrel 17. The configuration consisting of the solenoid 18 and the air barrel 17 generates negative pressure in the exhaled breath chamber 20 to introduce exhaled breath into the exhaled breath chamber 20, and corresponds to a negative pressure generating unit. The air barrel 17 also changes the volume of the exhaled breath chamber 20, and corresponds to a volume changing unit.

[0032] The pressure sensor 16 detects the pressure inside the expiratory gas chamber 20. The pressure inside the expiratory gas chamber 20 fluctuates in response to the subject's blowing of exhaled gas into the expiratory gas flow path 33 and changes in the volume of the expiratory gas chamber 20. The pressure sensor 16 is a pressure sensor with a semiconductor strain gauge formed on the surface of a diaphragm. In the pressure sensor 16, the electrical resistance changes due to the piezo-resistance effect in response to deformation of the diaphragm due to external force (pressure). The pressure sensor 16 converts the change in electrical resistance into an electrical signal. Note that the pressure sensor 16 may be a pressure sensor of another type.

[0033] The gas sensor 15 is an example of a component measuring unit. The gas sensor 15 includes a gas sensor and measures the gas (alcohol) in the breath drawn into the gas sensor chamber 15a. In this embodiment, an electrochemical sensor having a gas sensor that flows a current when it comes into contact with alcohol is used as the gas sensor 15. This electrochemical sensor indicates the alcohol concentration in the breath based on the value of the current flowing through the gas sensor. One example is a sensor that uses Pt (platinum) or a Pt alloy as the anode and cathode and sulfuric acid (H2SO4) as the electrolyte. This sensor indicates the alcohol concentration in the breath based on the change in current that occurs when alcohol molecules are oxidized by the platinum catalyst.

[0034] The gas sensor 15 only needs to be able to measure the alcohol concentration in the breath. Therefore, various types of alcohol sensors can be used as the gas sensor 15, such as a semiconductor sensor whose electrical resistance changes due to a reaction between oxygen adsorbed on a metal oxide and alcohol in the gas (i.e., a semiconductor sensor whose electrical resistance changes depending on the alcohol concentration in the gas).

[0035] 4 is a block diagram showing the overall configuration of the exhaled breath component measuring device 10 according to the first embodiment of the present invention. The exhaled breath component measuring device 10 includes a display unit 11a, an input I / F 13, a gas sensor 15, a pressure sensor 16, a solenoid 18, an exhaled breath accommodating unit 20 (an inlet 21a, a flow path 22, a gas sensor chamber 15a, a flow path 23, an air barrel 17, and a flow path 24), a control unit 100, an output interface (output I / F) 11, and a storage unit 28.

[0036] The output I / F 11 is a device that outputs video and audio, such as a display, a speaker, etc. The output I / F 11 includes a display unit 11a, which is an example of an output unit.

[0037] The storage unit 28 is a computer-readable recording medium, such as a semiconductor recording medium, a magnetic recording medium, or an optical recording medium, or a combination of these recording media. The storage unit 28 stores a program that defines the operation of the control unit 100 and various information (threshold values, etc.).

[0038] 5 is a diagram showing functional blocks realized by the control unit 100 of the exhaled breath component measuring device 10 according to the first embodiment of the present invention. The control unit 100 is a computer such as a CPU (Central Processing Unit). By reading and executing a program stored in the storage unit 28, the control unit 100 realizes an exhaled breath inflow determination unit 101, an operation control unit 102, an abnormality determination unit 103, an alcohol concentration measurement unit 104, a drivability determination unit 105, and an output information generation unit 106, as shown in FIG.

[0039] The expiratory gas inflow determination unit 101 determines whether or not exhaled gas has flowed into the expiratory gas flow path 33 and whether or not the exhaled gas continues to flow into the expiratory gas flow path 33, based on the detection result of the pressure sensor 16. Specifically, the expiratory gas inflow determination unit 101 determines that exhaled gas is flowing into the expiratory gas flow path 33 when the pressure detected by the pressure sensor 16 at the time when it becomes possible to blow out the exhaled gas has increased by a threshold pressure difference Thp1 or more.

[0040] The operation control unit 102 drives the solenoid 18 based on the determination result of the breath inflow determination unit 101. For example, if the breath inflow determination unit 101 determines that the duration of the inflow of breath into the breath flow path 33 exceeds the threshold time Tht1 (e.g., 3 seconds), the operation control unit 102 outputs a solenoid control signal to the solenoid 18 for a certain period of time (e.g., 200 ms) and then stops the output, causing the volume of the air barrel 17 to decrease (contract) and then increase. In response to this increase (expansion) in the volume of the air barrel 17, the breath in the breath flow path 33 is drawn into the breath storage unit 20 (particularly, the gas sensor chamber 15a). When the operation control unit 102 starts outputting the solenoid control signal, it outputs drive information indicating the start of drive of the solenoid 18 to the abnormality determination unit 103.

[0041] When the volume of the exhaled breath storage section 20 (volume of the air barrel 17) is changed by driving the solenoid 18, i.e., when exhaled breath is introduced into the exhaled breath storage section 20 from the inlet 21a, the abnormality determination section 103 determines whether or not there is an abnormality in the exhaled breath blowing pressure in the exhaled breath flow path 33 based on the output of the pressure sensor 16 corresponding to the change in volume.

[0042] Here, as an example of an abnormality, an abnormality (incorrect measurement) in which the exhaled air from the subject is not blown into the exhaled air flow path 33 when the exhaled air is taken in will be described.

[0043] First, the exhaled air inflow determination unit 101 does not take in exhaled air unless the pressure difference of the pressure sensor 16 due to exhaled air exceeds the threshold pressure difference Thp1 for a period of time longer than the threshold time Tht1. Therefore, for example, in an abnormal state where exhaled air is not being blown out from the subject, exhaled air is not taken in the exhaled air storage unit 20.

[0044] FIG. 6 is a graph showing an example of the output of the pressure sensor 16 (pressure in the expiratory gas chamber 20) when there is no abnormality. In FIG. 6, when the subject is not blowing his / her exhaled breath into the expiratory gas flow path 33 (before timing t1), the pressure in the expiratory gas chamber 20 indicates atmospheric pressure P0. Timing t1 is the timing when the subject starts blowing his / her exhaled breath into the expiratory gas flow path 33. Timing t2 is the timing when the pressure difference from timing t1 becomes larger than the threshold pressure difference Thp1 due to the blowing of the exhaled breath. Thereafter, the output of the pressure sensor 16 maintains approximately the blowing pressure P1 due to the blowing of the exhaled breath. Timing t3 is the timing when the duration of the state in which the pressure difference from timing t1 is larger than the threshold pressure difference Thp1 reaches the threshold time Tht1, and the operation control unit 102 starts outputting a solenoid control signal to drive the solenoid 18.

[0045] The solenoid 18 begins to expand in response to the solenoid control signal, thereby compressing the air barrel 17 and reducing the volume of the air barrel 17 (expiratory gas chamber 20). This increases the pressure in the expiratory gas chamber 20, and the increase exceeds the threshold pressure difference Thp2. After the solenoid 18 stops expanding, the pressure in the expiratory gas chamber 20 decreases and returns to the original blowing pressure P1 at timing t4, which is the threshold time Tht2 after the solenoid 18 began to expand.

[0046] At time t5, a predetermined time (e.g., 200 ms) after time t3 when the operation control unit 102 started to output the solenoid control signal, the operation control unit 102 stops the solenoid control signal. This causes the solenoid 18 to contract, expanding the air barrel 17 and increasing the volume of the air barrel 17 (expiratory-gas chamber 20). This causes the pressure in the expiratory-gas chamber 20 to decrease. The decrease exceeds the threshold pressure difference Thp3. After the contraction of the solenoid 18 stops, the pressure in the expiratory-gas chamber 20 increases, and at time t6, when the threshold time Tht3 has elapsed since the start of contraction of the solenoid 18, the pressure returns to the original blowing pressure P1. When the subject finishes blowing their exhaled breath at time t7, the pressure in the expiratory-gas chamber 20 gradually decreases and returns to atmospheric pressure P0.

[0047] 7 is a graph showing an example of the output of the pressure sensor 16 (pressure inside the expiratory gas chamber 20) when there is an abnormality in the blowing. As in the normal case of FIG. 6, when the subject continues blowing for a threshold time Tht1 such that the pressure difference is equal to or greater than the threshold pressure difference Thp1, the operation control unit 102 outputs a solenoid control signal to the solenoid 18 at timing t3 to extend the solenoid 18. However, if the pressure of the blowing by the subject becomes lower than before timing t3 (typically, when the subject stops blowing or begins to inhale), the pressure change inside the expiratory gas chamber 20 due to the extension of the solenoid 18 and the expansion of the air barrel 17 will not be the same as that shown in FIG. 6.

[0048] First, at time t3 when the solenoid 18 begins to expand, the pressure from the subject's blowout ceases. Even though the volume of the air barrel 17 decreases due to the expansion of the solenoid 18, the pressure in the expiratory gas chamber 20 does not rise sufficiently, and the increase in pressure does not exceed the threshold pressure difference Thp2. At time t4, when the threshold time Tht2 has elapsed since the solenoid 18 began to expand, the pressure in the expiratory gas chamber 20 returns to atmospheric pressure P0, not blowout pressure P1, and stabilizes (note that if the subject is inhaling, the pressure stabilizes at a pressure below atmospheric pressure P0). At time t5, the solenoid control signal is stopped and the solenoid 18 begins to contract, increasing the volume of the air barrel 17. This decreases the pressure in the expiratory gas chamber 20, but by this point, the pressure is already below atmospheric pressure P0. Then, at time t6, when the threshold time Tht3 has elapsed, the pressure in the expiratory gas chamber 20 has returned to atmospheric pressure P0 and stabilized.

[0049] Therefore, the abnormality determination unit 103 determines whether or not an abnormality exists based on a change in the output of the pressure sensor 16 in response to a change in the volume of the expiratory gas chamber 20. Specifically, the abnormality determination unit 103 determines that an abnormality exists if the increase in pressure detected by the pressure sensor 16 when the solenoid 18 reduces the volume of the expiratory gas chamber 20 does not become equal to or greater than a first threshold value (for example, the threshold pressure difference Thp2 in FIGS. 6 and 7). Furthermore, if the pressure detected by the pressure sensor 16 is below a second threshold value (for example, a value greater than the atmospheric pressure P0 in FIGS. 6 and 7 by the threshold pressure difference Thp1) when a predetermined time (for example, the threshold time Tht2 in FIGS. 6 and 7) has elapsed since the solenoid 18 started to reduce the volume of the expiratory gas chamber 20, the abnormality determination unit 103 determines that blowing to obtain the blowing pressure P1 is not being maintained, and determines that an abnormality exists.

[0050] Furthermore, the abnormality determination unit 103 determines that an abnormality exists if the decrease in pressure detected by the pressure sensor 16 when the solenoid 18 increases the volume of the expiratory gas chamber 20 is below a third threshold value (for example, the threshold pressure difference Thp3 in FIGS. 6 and 7). Furthermore, if the pressure detected by the pressure sensor 16 is below a fourth threshold value (for example, a value greater than the atmospheric pressure P0 in FIGS. 6 and 7 by the threshold pressure difference Thp1) when a predetermined time (for example, the threshold time Tht3 in FIGS. 6 and 7) has elapsed since the solenoid 18 started to increase the volume of the expiratory gas chamber 20, the abnormality determination unit 103 determines that blowing out sufficient to obtain the blowing pressure P1 is not being maintained, and determines that an abnormality exists.

[0051] The alcohol concentration measurement unit 104 measures the concentration of alcohol in the breath based on the output of the gas sensor 15. Specifically, the alcohol concentration measurement unit 104 calculates the alcohol concentration in the breath based on the output current of the gas sensor 15.

[0052] The driving capability determination unit 105 determines whether the subject is fit to drive based on the alcohol concentration in the breath calculated by the alcohol concentration measurement unit 104. The driving capability determination unit 105 determines that the subject is fit to drive when the alcohol concentration in the breath is equal to or lower than the driving capability determination threshold stored in the memory unit 28.

[0053] The output information generation unit 106 causes the display unit 11a to display various types of information. The output information generation unit 106 causes the display unit 11a to display operation guide information such as an instruction to wait for breath blowing, an instruction to blow breath, or an instruction to end blowing. The output information generation unit 106 also causes the display unit 11a to display the numerical value of the alcohol concentration in the breath, the determination result of the driving feasibility determination unit 105, the determination result of the breath inflow determination unit 101, the determination result of the abnormality determination unit 103, and the like.

[0054] 8A to 8C are flowcharts illustrating the operation of the exhaled breath component measuring device according to the first embodiment of the present invention. First, when the subject presses the power switch 12, the output information generating unit 106 causes the display unit 11a to display a waiting state for blowing out during a waiting time (e.g., 5 seconds) until measurement becomes possible (step S101).

[0055] After the waiting time has elapsed, the output information generating unit 106 causes the display unit 11a to display a blowout instruction to blow out the exhaled air into the mouthpiece 30 for a predetermined time (for example, 5 seconds) (step S102).

[0056] When the subject exhales into the mouthpiece 30 through the inlet 31 in response to the blow-out instruction display, the exhaled air passes through the exhaled air flow path 33. At this time, the pressure of the exhaled air is transmitted into the exhaled air storage section 20 through the inlet 21a and detected by the pressure sensor 16.

[0057] The expiratory gas inflow determination unit 101 calculates the pressure difference in the expiratory gas storage unit 20 (i.e., the magnitude of the pressure increase from the pressure at the time of step S101) based on the output of the pressure sensor 16. If the pressure difference is equal to or less than the threshold pressure difference Thp1 (NO in step S103), the process returns to step S102.

[0058] On the other hand, if the pressure difference inside the expiratory gas storage section 20 is greater than the threshold pressure difference Thp1 (YES in step S103), the expiratory gas inflow determination section 101 outputs blowout detection information indicating the detection of blowout to the output information generation section 106. Upon receiving the blowout detection information, the output information generation section 106 causes the display section 11a to display an indication that blowout is occurring (step S104).

[0059] If the pressure difference in the expiratory gas storage section 20 becomes equal to or less than the threshold pressure difference Thp1 after outputting the blow-out detection information (NO in step S105), the expiratory gas inflow determination section 101 outputs blow-out interruption information indicating that blow-out has been interrupted to the output information generation section 106. Upon receiving the blow-out interruption information, the output information generation section 106 causes the display section 11a to display a message indicating a blow-out interruption error (step S107).

[0060] If the pressure difference in the expiratory gas chamber 20 is greater than the threshold pressure difference Thp1 after outputting the blowout detection information (YES in step S105), the expiratory gas inflow determination unit 101 determines whether the elapsed time t since determining YES in step S103 is longer than the threshold time Tht1 (step S106). Here, the elapsed time t represents the time during which the pressure difference in the expiratory gas chamber 20 continues to be greater than the threshold pressure difference Thp1. If the elapsed time t is equal to or less than the threshold time Tht1 (NO in step S106), the process returns to step S104.

[0061] If the elapsed time t is longer than the threshold time Tht1 (YES in step S106), the expired gas inflow determination unit 101 outputs start information indicating the start of the intake of expired gas to the operation control unit 102. Upon receiving the start information, the operation control unit 102 outputs a solenoid control signal to the solenoid 18 to extend the solenoid 18 (step S108). This reduces the volume of the air barrel 17, and at least a portion of the gas in the expired gas storage unit 20 is discharged from the inlet 21a. When the operation control unit 102 starts driving the solenoid 18, it outputs drive information to the abnormality determination unit 103.

[0062] The abnormality determination unit 103 determines whether the pressure difference inside the expiratory gas chamber 20 (i.e., the magnitude of the increase in pressure from the solenoid) has become larger than the threshold pressure difference Thp2 due to the extension of the solenoid 18 (step S109). If the pressure difference inside the expiratory gas chamber 20 is equal to or smaller than the threshold pressure difference Thp2 despite the volume inside the expiratory gas chamber 20 having decreased due to the extension of the solenoid 18 (NO in step S109), the abnormality determination unit 103 determines that there is an abnormality in the blowing pressure and outputs abnormal pressure detection information indicating the detection of an abnormal pressure to the output information generation unit 106 (step S116).

[0063] If the pressure difference in the expiratory gas chamber 20 normally exceeds the threshold pressure difference Thp2 (YES in step S109), the abnormality determination unit 103 determines whether the elapsed time t from step S106 is longer than the threshold time Tht2 (step S110). If the elapsed time t is equal to or shorter than the threshold time Tht2 (NO in step S110), step S110 is repeated. If the elapsed time t exceeds the threshold time Tht2 (YES in step S110), the abnormality determination unit 103 determines whether the pressure difference in the expiratory gas chamber 20 at that time (i.e., the magnitude of the pressure increase from the pressure at the time of step S101) can be maintained at a value greater than the threshold pressure difference Thp1 (step S111). If the pressure difference in the exhaled breath accommodating section 20 at this point is less than or equal to the threshold pressure difference Thp1 (NO in step S111), the abnormality determination section 103 determines that there is an abnormality in the blowing pressure and outputs abnormal pressure detection information indicating the detection of an abnormal pressure to the output information generation section 106 (step S116).

[0064] If the pressure difference in the expiratory gas chamber 20 exceeds the threshold pressure difference Thp1 (YES in step S111), the operation control unit 102 stops outputting the solenoid control signal to the solenoid 18 and contracts the solenoid 18 (step S112). This increases the volume of the air barrel 17, and expiratory gas is taken into the expiratory gas chamber 20 from the expiratory gas flow path 33.

[0065] The abnormality determination unit 103 determines whether the pressure difference in the expiratory gas chamber 20 (i.e., the magnitude of the pressure decrease from the pressure immediately before the solenoid control signal is stopped) is greater than the threshold pressure difference Thp3 (step S113). If the pressure difference in the expiratory gas chamber 20 is equal to or less than the threshold pressure difference Thp3 (NO in step S113), the abnormality determination unit 103 determines that there is an abnormality in the blowing pressure, and outputs abnormal pressure detection information indicating the detection of an abnormal pressure to the output information generation unit 106 (step S116).

[0066] If the pressure in the expiratory gas chamber 20 normally exceeds the threshold pressure difference Thp3 (YES in step S113), the abnormality determination unit 103 determines whether the elapsed time t from step S112 is longer than the threshold time Tht3 (step S114). If the elapsed time t is equal to or shorter than the threshold time Tht3 (NO in step S114), step S114 is repeated. If the elapsed time t exceeds the threshold time Tht3 (YES in step S114), the abnormality determination unit 103 determines whether the pressure difference in the expiratory gas chamber 20 at that time (i.e., the magnitude of the pressure increase from the pressure at the time of step S101) can be maintained at a value greater than the threshold pressure difference Thp1 (step S115). If the pressure difference in the exhaled breath accommodating section 20 at this point is less than or equal to the threshold pressure difference Thp1 (NO in step S115), the abnormality determination section 103 determines that there is an abnormality in the blowing pressure and outputs abnormal pressure detection information indicating the detection of an abnormal pressure to the output information generation section 106 (step S116).

[0067] If the pressure difference in the exhaled breath accommodating section 20 exceeds the threshold pressure difference Thp1 (YES in step S115), the abnormality determination section 103 determines that there is no abnormality and activates the gas sensor 15. The gas sensor 15 detects the alcohol concentration of the exhaled breath in the gas sensor chamber 15a and outputs the detection result to the alcohol concentration measurement section 104.

[0068] The alcohol concentration measurement unit 104 measures (analyzes) the alcohol concentration in the breath based on the detection result of the gas sensor 15 (step S117). At this time, the alcohol concentration measurement unit 104 may output analysis start information indicating the start of analysis to the output information generation unit 106, and the output information generation unit 106 may cause the display unit 11a to display an indication that the breath blowing has ended in response to receiving the analysis start information. Upon completing the measurement of the alcohol concentration in the breath, the alcohol concentration measurement unit 104 outputs the alcohol concentration measurement result to the output information generation unit 106 and the driving feasibility determination unit 105.

[0069] Upon receiving the alcohol concentration measurement result, the output information generating unit 106 causes the display unit 11a to display the alcohol concentration indicated by the measurement result (step S118).

[0070] If the alcohol concentration measurement result exceeds the driving capability determination threshold, the driving capability determination unit 105 determines that driving is not possible, and outputs driving capability information indicating that driving is not possible to the output information generation unit 106. On the other hand, if the alcohol concentration measurement result does not exceed the driving capability determination threshold, the driving capability determination unit 105 determines that driving is possible, and outputs driving capability information indicating that driving is possible to the output information generation unit 106. The driving capability determination threshold is stored in the memory unit 28.

[0071] When receiving the operation disabled information, the output information generating unit 106 causes the display unit 11a to display an indication that the operation is disabled, and when receiving the operation enabled information, causes the display unit 11a to display an indication that the operation is enabled (step S119). Here, the display indicating that the operation is disabled is an example of information corresponding to the determination result of the abnormality determination unit 103 that an abnormality exists.

[0072] According to this embodiment, the presence or absence of an abnormality in the blowing pressure is determined based on the output of the pressure sensor 16 (pressure inside the expiratory gas chamber 20) in response to a change in the volume of the expiratory gas chamber 20. Therefore, when the gas inside the expiratory gas flow path 33 is drawn into the expiratory gas chamber 20 by the action of the solenoid 18 and the air barrel 17, the exhaled gas of the subject can be reliably introduced into the expiratory gas chamber 20.

[0073] In this embodiment, the abnormality determination unit 103 determines whether or not there is an abnormality by determining whether the pressure difference inside the expiratory gas storage unit 20 exceeds or falls below a predetermined threshold pressure at a predetermined timing. Alternatively, the abnormality determination unit 103 may determine that there is no abnormality when the absolute value of the pressure inside the expiratory gas storage unit 20 when the capacity of the expiratory gas storage unit 20 decreases exceeds a predetermined threshold, or may determine that there is no abnormality when the absolute value of the pressure inside the expiratory gas storage unit 20 when the capacity of the expiratory gas storage unit 20 increases falls below the predetermined threshold.

[0074] Furthermore, in the above-described embodiment in which the air barrel 17 is first deflated and then expanded to take in exhaled breath, the exhaled breath component measurement device 10 determines whether there is an abnormality in the blowing pressure by detecting an abnormality in the pressure inside the exhaled breath chamber 20 during and after deflation, inflation, and inflation, respectively. However, the abnormality in the pressure inside the exhaled breath chamber 20 may be detected only during deflation of the air barrel 17, only after deflation, or during and after deflation. In this case, if the pressure inside the exhaled breath chamber 20 during or after deflation of the air barrel 17 is normal, the output of the pressure sensor 16 may not be monitored thereafter, and the alcohol concentration measurement by the alcohol concentration measurement unit 104 (step S117 in FIG. 8C ) and subsequent processing may be initiated. This embodiment also makes it possible to determine whether there is an abnormality in the blowing pressure when exhaled breath is taken into the exhaled breath chamber 20.

[0075] Furthermore, the above-described exhaled breath component measuring device 10 uses the pressure sensor 16 provided in the exhaled breath accommodating section 20 to detect the blowing pressure of exhaled breath in the exhaled breath flow path 33. However, in addition to or instead of this, a pressure sensor that directly measures the pressure in the exhaled breath flow path 33 may be used to detect the blowing pressure of exhaled breath in the exhaled breath flow path 33. In this case, in addition to the through-hole 33a and the inlet 21a that communicate between the exhaled breath flow path 33 and the exhaled breath accommodating section 20, a through-hole and an inlet are provided to communicate between the exhaled breath flow path 33 and the pressure sensor.

[0076] <Second embodiment> In the second embodiment, the same configuration and operation as those in the first embodiment will not be described as appropriate. The hardware configuration of the exhaled breath component measuring device 10 in the second embodiment is the same as that of the exhaled breath component measuring device 10 in the first embodiment.

[0077] As described above, the breath inflow determination unit 101 determines that breath is flowing into the breath flow path 33, i.e., that the subject is blowing breath out, based on the pressure difference from the pressure at which breath can be blown out.

[0078] 9 is a diagram illustrating an example of a situation in which the subject's exhaled breath cannot be taken in due to an abnormality in the pressure inside the expiratory breath chamber 20 before the start of blowing. As shown in FIG. 9, if the subject inhales (inhales) while wearing the mouthpiece 30 in order to blow out the exhaled breath before starting to blow out the exhaled breath, the pressure inside the expiratory breath chamber 20 drops below atmospheric pressure P0 to pressure P2. If inhalation is stopped from this state at timing t1 (or if blowing is performed with insufficient pressure after inhalation is stopped), the pressure inside the expiratory breath chamber 20 gradually increases, and at timing t2 the pressure difference inside the expiratory breath chamber 20 reaches the threshold pressure difference Thp1, but no exhaled breath is blown out (or insufficient exhaled breath is blown out).

[0079] If this state is maintained for the threshold time Tht1, the breath component measuring device 10 will drive the solenoid 18 in the same manner as in the first embodiment to take in gas from the breath flow path 33 while the breath blowing pressure is insufficient, and will measure the alcohol concentration without taking in a sufficient amount of breath.

[0080] Therefore, in this embodiment, the possibility of an abnormality due to the above-mentioned cause occurring is reduced by providing the subject with guidance on inhalation and exhalation. In this embodiment, the output I / F 11 functions as a guidance unit and includes a speaker for outputting audio in addition to the display unit 11a of the first embodiment.

[0081] Fig. 10 is a graph showing an example of the output (pressure inside the exhaled breath accommodating section 20) of the pressure sensor 16 according to the second embodiment of the present invention. Fig. 11 is a flowchart illustrating the operation of the exhaled breath component measuring device according to the second embodiment of the present invention. In the exhaled breath component measuring device 10 according to this embodiment, when the power switch 12 is pressed, the output information generating section 106 causes the display section 11a and the speaker to display and output a guidance voice (wait guidance) to encourage the user to wait for a waiting time (e.g., 5 seconds) until measurement becomes possible (step S201).

[0082] After the standby time has elapsed, the output information generating unit 106 causes the display unit 11a and the speaker to display and output audio guidance (inhalation guidance) to encourage the subject to hold the mouthpiece 30 in their mouth and inhale for a predetermined time (e.g., 3 seconds) (step S202). At timing t1, when the subject starts inhaling in accordance with the inhalation guidance, the expiratory gas inflow determining unit 101 calculates the pressure difference within the expiratory gas storage unit 20 (i.e., the magnitude of the pressure decrease from the pressure at the time of the inhalation guidance) based on the output of the pressure sensor 16. If the pressure difference is equal to or less than the threshold pressure difference Thp4 (NO in step S203), the process returns to step S202.

[0083] When the pressure difference inside the expiratory gas accommodating section 20 becomes greater than the threshold pressure difference Thp4 at timing t2 (YES in step S203), the expiratory gas inflow determining section 101 outputs suction detection information indicating the detection of suction to the output information generating section 106. Upon receiving the suction detection information, the output information generating section 106 causes the display section 11a and the speaker to respectively display a guidance message and output a guidance voice (continue suction guidance) encouraging the user to continue suctioning (step S204).

[0084] If the pressure difference inside the expiratory gas storage section 20 becomes equal to or less than the threshold pressure difference Thp4 after outputting the suction information (NO in step S205), the expiratory gas inflow determination section 101 outputs suction interruption information indicating interruption of suction to the output information generation section 106. Upon receiving the suction interruption information, the output information generation section 106 causes the display section 11a and the speaker to display and output sound indicating an error, respectively (step S207).

[0085] If the pressure difference in the expiratory gas chamber 20 is greater than the threshold pressure difference Thp4 after outputting the suction detection information (YES in step S205), the expiratory gas inflow determination unit 101 determines whether the elapsed time t since determining YES in step S203 is longer than the threshold time Tht4 (step S206). Here, the elapsed time t represents the time during which the pressure difference in the expiratory gas chamber 20 continues to be greater than the threshold pressure difference Thp4. If the elapsed time t is equal to or less than the threshold time Tht4 (NO in step S206), the process returns to step S204.

[0086] If the elapsed time t becomes longer than the threshold time Tht4 at timing t3 (YES in step S206), the output information generation unit 106 causes the display unit 11a and the speaker to display and output audio guidance (breath-holding guidance) to encourage the user to hold their breath for a predetermined time (e.g., 3 seconds) while holding the mouthpiece 30 in their mouth (step S208). The output information generation unit 106 determines whether the elapsed time t from the breath-holding guidance is longer than the threshold time Tht5 (step S209). Here, the elapsed time t represents the time it takes for the pressure in the expiratory gas chamber 20 to return to atmospheric pressure P0 and stabilize. If the elapsed time t is equal to or shorter than the threshold time Tht5 (NO in step S209), the process returns to step S209.

[0087] When the elapsed time t becomes longer than the threshold time Tht5 at timing t4 (YES in step S209), the expiratory gas inflow determination unit 101 calculates the pressure difference in the expiratory gas chamber 20 (i.e., the magnitude of the pressure increase from the pressure at the time of breath-holding guidance) based on the output of the pressure sensor 16. The abnormality determination unit 203 determines whether the difference between the pressure difference calculated here and the pressure difference calculated in step S203 is within a predetermined error range (step S210). If the difference between the two pressure differences is greater than the predetermined error range (NO in step S210), the process returns to step S210.

[0088] If the difference between the two pressure differences is within a predetermined error range (YES in step S210), the expired gas inflow determination unit 101 stores the pressure in the expired gas storage unit 20 at that time as a reference pressure (step S211), and the output information generation unit 106 causes the display unit 11a and the speaker to display and output a guidance voice (blowout guidance) to encourage the user to blow out their breath while holding the mouthpiece 30 in their mouth for a predetermined time (e.g., 5 seconds) (step S212). After this, the process is the same as in the first embodiment, so description will be omitted; however, the expired gas inflow determination unit 101 sets the reference pressure stored in step S211 as the reference pressure for detecting blowout using the threshold pressure difference Thp1.

[0089] As described above, in the exhaled breath component measuring device 10 of this embodiment, the exhaled breath inflow measuring unit 101 detects that the subject has inhaled from the mouth, held their breath, and then blown out into the exhaled breath flow path 33 in that order, and the pressure at the time of breath holding is used as the reference pressure. Therefore, blowing out can be detected with this reference pressure set to atmospheric pressure P0, thereby reducing the possibility of an abnormality such as that shown in Figure 9 occurring.

[0090] In this embodiment, the display unit 11a and speaker are used as means for instructing the subject to inhale, hold their breath, and blow out, but in addition to or instead of these, a vibrator that vibrates the exhaled breath component measuring device 10 may be used. Furthermore, if the assumed user is someone who understands the above-mentioned steps for measuring alcohol concentration using the exhaled breath component measuring device 10 and can carry out the steps without guidance, some or all of the above guidance may be omitted.

[0091] Furthermore, in the above embodiment, the reference pressure was obtained by determining whether inhalation was actually performed using the threshold pressure difference Thp4 and the threshold time Tht4 in response to the inhalation guidance, but it may also be possible to simply provide inhalation guidance and then provide breath-holding guidance without determining whether inhalation was actually performed. In this case, as in the above embodiment, the pressure after the breath-holding guidance is stored as the reference pressure. In this case, too, blowing can be detected using the pressure when breath-holding was performed (Tao air pressure P0) as the reference pressure. [Explanation of symbols]

[0092] 10. Exhaled breath component measuring device 15 Gas Sensor 16 Pressure Sensor 17 Air Barrel 18 Solenoid 20 Exhalation chamber 100 control section 103 Abnormality determination section

Claims

1. an exhaled breath storage unit having an inlet for introducing the exhaled breath of the subject and storing the exhaled breath introduced through the inlet; an exhaled gas introduction section that introduces exhaled gas blown out of the subject's mouth into the introduction port; a component measuring unit for measuring a predetermined component of the exhaled breath introduced into the exhaled breath storage unit; an abnormality determination unit that determines whether or not there is an abnormality in the blowing pressure of the exhaled gas at the exhaled gas introduction unit when the exhaled gas is introduced into the exhaled gas storage unit from the introduction port; An exhaled breath component measuring device comprising:

2. 2. The exhaled breath component measuring device according to claim 1, wherein the abnormality determining section includes a pressure detecting section that detects the pressure inside the exhaled breath storage section, and determines whether or not the abnormality exists based on the pressure detected by the pressure detection.

3. a negative pressure generating unit configured to generate a negative pressure in the expiratory gas storage unit in order to introduce the expiratory gas into the expiratory gas storage unit; 3. The exhaled breath component measuring device according to claim 1, wherein the abnormality determining unit determines whether or not there is an abnormality in the blowing pressure during an operation for generating negative pressure by the negative pressure generating unit.

4. the negative pressure generating unit includes a volume changing unit for changing the volume of the expiratory gas storage unit, The exhaled breath component measuring device according to claim 3, which cites claim 2, wherein the abnormality determination unit determines that the abnormality exists if the change in pressure detected by the pressure detection unit when the volume change unit reduces the volume in preparation for generating the negative pressure is equal to or less than a first threshold value.

5. the negative pressure generating unit includes a volume changing unit for changing the volume of the expiratory gas storage unit, The exhaled breath component measuring device according to claim 3, which cites claim 2, wherein the abnormality determination unit determines that the abnormality exists when the pressure detected by the pressure detection unit becomes equal to or less than a second threshold value after the volume change unit reduces the volume in preparation for generating the negative pressure.

6. the negative pressure generating unit includes a volume changing unit for changing the volume of the expiratory gas storage unit, The exhaled breath component measuring device according to claim 3, which cites claim 2, wherein the abnormality determination unit determines that an abnormality exists if the change in pressure detected by the pressure detection unit when the volume change unit increases the volume to generate the negative pressure is equal to or less than a third threshold value.

7. the negative pressure generating unit includes a volume changing unit for changing the volume of the expiratory gas storage unit, The exhaled breath component measuring device according to claim 3, which cites claim 2, wherein the abnormality determination unit determines that the abnormality exists when the pressure detected by the pressure detection unit becomes equal to or less than a fourth threshold value after the volume change unit increases the volume to generate the negative pressure.

8. and an expiratory gas inflow measuring unit that detects that the subject has inhaled, held their breath, and exhaled into the expiratory gas inlet in this order.

2. The exhaled breath component measuring device according to claim 1, wherein the abnormality determining unit determines whether or not an abnormality exists based on the blowing pressure from a reference pressure that is a pressure when the breath is held.

9. 1. An abnormality determination method for determining whether or not there is an abnormality in exhaled breath component measurement, in which predetermined components are measured for exhaled breath stored in an exhaled breath storage unit having an inlet for introducing exhaled breath of a subject, the method comprising: An abnormality determination method for determining an abnormality in the expiratory gas blowing pressure at an expiratory gas inlet section that introduces the expiratory gas blown out of the subject's mouth into the inlet when the expiratory gas is introduced from the inlet into the expiratory gas storage section.

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