JP6465621B2 - Gas detector - Google Patents

Description

  The present invention relates to a gas detection device for detecting gas.

  Patent Document 1 discloses an expiratory component measuring device for measuring the concentration of a detection target component such as bad breath causing gas or alcohol. In this exhalation component measuring device, the concentration of the detection target component contained in the exhalation is measured when the exhalation taken into the inside of the body from the intake port contacts the sensing element of the gas sensor.

JP 2001-190523 A

  By the way, in the gas detection apparatus as shown in Patent Document 1, when not in use, the gas sensor in the container may be exposed to gas outside the container through the intake port and deteriorate. In addition, liquid outside the body may enter the body through the intake port, and this liquid may be applied to the gas sensor, causing problems such as failure.

  This invention is made | formed in view of the said situation, Comprising: It aims at providing the gas detection apparatus which can suppress that degradation and malfunction of a gas sensor arise.

  In order to solve the above problems, a gas detection apparatus according to the present invention includes an inflow port through which a sample gas flows in, an outflow port through which the sample gas flowing in from the inflow port flows out, and ventilation through the inflow port and the outflow port. A gas sensor for detecting a detection target component contained in the sample gas, a primary side shutter part that can be opened and closed to close the inflow port, and a primary side shutter part that are disposed in space. The outlet is closed when the primary shutter portion closes the inlet, and the outlet is opened when the primary shutter portion opens the inlet. And a secondary shutter unit.

  The gas detection device according to the present invention can close the inflow port with the primary shutter portion and close the outflow port with the secondary shutter portion. For this reason, it can suppress that a gas sensor is exposed to gas and deteriorates, or that a liquid is applied to a gas sensor and a failure occurs. In addition, since the primary shutter unit and the secondary shutter unit are linked, the user can easily close or open the inlet and the outlet only by moving one shutter unit.

It is a perspective view of the gas detection apparatus of embodiment of this invention. It is a perspective sectional view showing the longitudinal section of the gas detection device. It is a perspective view of an adsorption unit and a gas sensor provided in the gas detection device. It is a perspective sectional view showing the transverse section of the gas detection device. It is a perspective sectional view showing the upper end part of the gas detection device. It is a horizontal sectional view of the gas detection device. It is the perspective view which abbreviate | omitted illustration of the case when the shutter member of the said gas detection apparatus is arrange | positioned in an open position. It is a perspective view which shows an upper end part when the shutter member of the said gas detection apparatus is arrange | positioned in an open position. It is the front view which fractured | ruptured partially the gas sensor of the said gas detection apparatus. It is sectional drawing which shows the sensor element of the said gas sensor.

  Hereinafter, the gas detection apparatus 1 of embodiment of this invention is demonstrated. FIG. 1 shows a gas detection device 1 of the present embodiment. In the following description, in FIG. 1, the direction indicated by D <b> 1 is the front, the direction indicated by D <b> 2 is the upper side, and the direction indicated by D <b> 3 is the left side.

  The gas detection device 1 of the present embodiment is an alcohol concentration detection device for detecting the alcohol concentration contained in exhaled breath that is a sample gas. In addition, the gas detection apparatus to which this invention is applied is not restrict | limited to what used the detection target component (detection target gas) as alcohol. For example, the detection target component may be a bad breath odor causing gas (for example, methyl mercaptan) included in exhaled breath, carbon monoxide gas generated during incomplete combustion, or the like. Further, the gas detection device to which the present invention is applied is not limited to the gas concentration detection device that measures the concentration of the detection target component, and may be a device that detects the presence or absence of the detection target component.

  As shown in FIGS. 1 to 3, the gas detection device 1 of the present embodiment includes a case 2, an adsorption unit 4, a circuit board 10, a control unit, a display device 11, a gas sensor 8, a battery 12, and an operation unit 13. I have.

  The case 2 is formed in a rectangular hollow plate shape when viewed from the front. The thickness direction of the case 2 is parallel to the front-rear direction, and the length direction of the case 2 is parallel to the vertical direction.

  As shown in FIG. 2, the case 2 includes a front case body 20 constituting the front half part and a rear case body 21 constituting the rear half part. The front case body 20 is formed in a shallow box shape opened rearward, and the rear case body 21 is formed in a shallow box shape opened forward. The front case body 20 and the rear case body 21 are coupled in a state where the peripheral edge portions are butted together.

  The front case body 20 includes a front plate portion 22 that constitutes the front surface portion of the case 2. The rear case body 21 includes a rear plate portion 23 that constitutes a rear surface portion of the case 2.

  The front plate portion 22 of the front case body 20 is formed with an inflow port 24 for inhaling exhaled air when the alcohol concentration is measured. The inflow port 24 is located at the upper end portion of the front plate portion 22.

  As shown in FIG. 4, the rear plate portion 23 of the rear case body 21 is formed with an outlet 25 through which exhaled air flowing in from the inlet 24 flows out. The outlet 25 is located at the upper end of the rear plate portion 23 of the rear case body 21.

  The inflow port 24 and the outflow port 25 are formed in a rectangular shape whose length direction is parallel to the left-right direction, and have the same shape. Both the inflow port 24 and the outflow port 25 are located in the center in the width direction of the case 2 and overlap each other when viewed from the front.

  As shown in FIG. 2, the upper end portion of the case 2 is provided with a partition portion 26 that partitions the inside of the case 2 so as to be divided into upper and lower portions. The partition portion 26 includes a front partition piece portion 27 protruding rearward from the front plate portion 22 of the front case body 20 and a rear partition piece portion 28 protruding forward from the rear plate portion 23 of the rear case body 21. Yes. The thickness direction of each of the front partition piece portion 27 and the rear partition piece portion 28 is parallel to the vertical direction, and the rear end surface of the front partition piece portion 27 and the front end surface of the rear partition piece portion 28 are abutted.

  The interior of the case 2 is partitioned by a partition 26 into a first region 29 located above the partition 26 and a second region 30 located below the partition 26.

  The first region 29 is located at the upper end portion of the case 2. The suction unit 4 is disposed in the first region 29. As shown in FIG. 3, the suction unit 4 includes a detection chamber forming body 40, a suction member 41, and a shutter member 42.

  The detection chamber forming body 40 is formed in a box shape opened downward, and its length direction is parallel to the left-right direction. A pair of partition walls 43 and 44 are formed in the detection chamber forming body 40 and are spaced apart in the left-right direction. Both the partition walls 43 and 44 are formed in a plate shape whose thickness direction is parallel to the left-right direction.

  The inside of the detection chamber forming body 40 is partitioned into three chambers arranged in the left-right direction by both partition walls 43 and 44. Among these chambers, the chambers located at the left and right ends of the detection chamber forming body 40 constitute storage chambers 45 and 47, respectively, and the chamber located at the center in the left-right direction constitutes the gas detection chamber 46.

  The left storage chamber 45 is a chamber composed of an upper wall portion 48 (see FIG. 2), a front wall portion 49, a rear wall portion 50, a side wall portion 51 (see FIG. 4), and a partition wall 43. However, it opens downward. The right storage chamber 47 is a chamber constituted by the upper wall portion 48, the front wall portion 49, the rear wall portion 50, the side wall portion 52 (see FIG. 4), and the partition wall 44 of the detection chamber forming body 40. Is open.

  Each of the storage chambers 45 and 47 of this embodiment constitutes an adsorbent storage unit in which the adsorbent is disposed. Specifically, the suction member 41 is stored in each of the storage chambers 45 and 47 so as to fill the entire interior of the storage chambers 45 and 47. Each adsorption member 41 includes a carrier 53 and an adsorbent carried on the carrier 53. For the carrier 53 of each adsorption member 41, for example, a sponge that is a porous compression material is used. For the adsorbent of each adsorbing member 41, for example, activated carbon that adsorbs alcohol is used.

  The gas detection chamber 46 includes an upper wall portion 48 (see FIG. 2) of the detection chamber forming body 40, a front wall portion 49, a rear wall portion 50, and both partition walls 43 and 44, and opens downward. .

  As shown in FIG. 4, communication ports 54 and 55 are formed in portions corresponding to the gas detection chamber 46 in each of the front wall portion 49 and the rear wall portion 50 of the detection chamber forming body 40. Hereinafter, if necessary, the communication port 54 formed in the front wall portion 49 of the detection chamber forming body 40 is referred to as a primary side communication port 54, and the communication port formed in the rear wall portion 50 of the detection chamber forming body 40. The port 55 is referred to as a secondary side communication port 55.

  In the present embodiment, each of the communication ports 54 and 55 is composed of a plurality of slit holes 56 formed side by side in the left-right direction. Each slit hole 56 is vertically long.

  The primary side communication port 54 faces the inflow port 24 of the case 2, and the inside of the gas detection chamber 46 communicates with the inflow port 24 through the primary side communication port 54. The secondary side communication port 55 faces the outflow port 25 of the case 2, and the inside of the gas detection chamber 46 communicates with the outflow port 25 through the secondary side communication port 55. That is, the inside of the gas detection chamber 46 is a ventilation space that allows the inflow port 24 and the outflow port 25 to pass through.

  The exhaled air that has flowed into the gas detection chamber 46 from the inflow port 24 through the primary side communication port 54 flows backward between the partition walls 43 and 44 while contacting the gas sensor. The interior of the gas detection chamber 46 is covered with an upper wall portion 48 (see FIG. 2) of the detection chamber forming body 40 and both sides are covered with partition walls 43 and 44. For this reason, the exhaled air that has flowed into the gas detection chamber 46 does not easily enter the other part of the case 2 and is smoothly discharged from the outlet 25.

  Each partition wall 43, 44 is formed with a through hole 57 (see FIGS. 4 and 3) that allows the interior of the gas detection chamber 46 and the interior of the storage chamber 45 to pass therethrough. The inside of the gas detection chamber 46 communicates with the left and right storage chambers 45 through the through holes 57 of the partition walls 43 and 44. For this reason, even if the alcohol in the exhaled breath and the gas that existed in the measurement atmosphere remain in the gas detection chamber 46 after the measurement, the alcohol and the gas are gradually adsorbed by the adsorbent included in the adsorbing member 41.

  As shown in FIG. 3, latching portions 58 and 59 are formed at the lower ends of the left and right sides of the detection chamber forming body 40. As shown in FIG. 5, the suction unit 4 is fixed to the case 2 by the hook portions 58 and 59 being hooked on the partition portion 26. The lower opening of each storage chamber 45 of the detection chamber forming body 40 is closed by the partition portion 26. For this reason, it is difficult for gas to flow into the respective storage chambers 45 from the first region 29 side. Therefore, the adsorption member 41 accommodated in each storage chamber 45 has a structure capable of actively adsorbing only the gas present in the gas detection chamber 46, and the adsorption performance is unlikely to deteriorate.

  The shutter member 42 shown in FIG. 3 is attached to the detection chamber forming body 40 so as to be slidable in the left-right direction. The shutter member 42 is U-shaped with a side sectional shape opened downward.

  The shutter member 42 includes a pair of shutter portions 60 and 61 that are arranged to be spaced apart from each other in the front-rear direction, and a connection portion 62 that connects the shutter portions 60 and 61. Hereinafter, if necessary, the shutter unit 60 disposed on the front side of the shutter units 60 and 61 is referred to as a primary shutter unit 60, and the shutter unit 61 disposed on the rear side is referred to as a secondary shutter unit. It is described as 61.

  The primary shutter part 60 is disposed along the front surface of the detection chamber forming body 40. The secondary shutter portion 61 is disposed along the rear surface of the detection chamber forming body 40. The connecting portion 62 is disposed along the upper surface of the detection chamber forming body 40. The upper end portions of both shutter portions 60 and 61 are connected by a connecting portion 62. For this reason, the primary side shutter part 60 and the secondary side shutter part 61 interlock | cooperate.

  A supported portion 63 is formed on the shutter member 42, and a shutter member supporting portion 64 that supports the supported portion 63 slidably in the left-right direction is formed on the detection chamber forming body 40.

  The supported portion 63 of the shutter member 42 according to the present embodiment includes a first protrusion 65, a second protrusion 66, and a groove 67. As shown in FIG. 6, the first protrusion 65 is formed at the left end of each shutter part 60, 61 and protrudes toward the detection chamber forming body 40 in the front-rear direction. The 2nd protrusion 66 is formed in the right end part of each shutter part 60 and 61, and protrudes toward the detection chamber formation body 40 side in the front-back direction. As shown in FIG. 7, the recessed groove portion 67 is formed on the lower surface of the connecting portion 62 and extends in the left-right direction.

  The shutter member support portion 64 of the detection chamber forming body 40 includes a first groove 68 (see FIG. 3), a second groove 69, and a protrusion 70.

  The first groove 68 (see FIG. 3) is formed in the left side portions of the front surface and the rear surface of the detection chamber forming body 40, respectively. The second groove 69 is formed in the right part of each of the front surface and the rear surface of the detection chamber forming body 40. Each first groove 68 and each second groove 69 extend in the left-right direction.

  As shown in FIG. 3, the first protrusions 65 of the corresponding shutter portions 60 and 61 are fitted into the first grooves 68 so as to be slidable in the left-right direction. As shown in FIG. 7, the second protrusions 66 of the corresponding shutter portions 60 and 61 are fitted into the second grooves 69 so as to be slidable in the left-right direction. Further, the projection 70 of the detection chamber forming body 40 is fitted in the concave groove portion 67 of the shutter member 42 so as to be slidable in the left-right direction. Thus, the shutter member 42 is attached to the detection chamber forming body 40 so as to be slidable in the left-right direction between the closed position shown in FIG. 3 and the open position shown in FIG.

  As shown in FIG. 3, the detection chamber forming body 40 includes a first dividing portion 73 that is divided into a right end portion 71 of each first groove 68 and a main portion 72 other than the first groove 68, and a left side of each second groove 69. An end portion 74 and a second dividing portion 76 that divides the other main portion 75 are formed.

  When the shutter member 42 is disposed at the closed position shown in FIG. 3, each first protrusion 65 enters the right end 71 of the corresponding first groove 68, and movement in the left-right direction is restricted. Thereby, the shutter member 42 is held at the closed position. When the shutter member 42 moves to the left from the closed position, each first protrusion 65 gets over the corresponding first dividing portion 73 and enters the main portion 72 of the corresponding first groove 68 to be slidable in the left-right direction. .

  When the shutter member 42 is disposed at the open position shown in FIG. 7, each second protrusion 66 enters the left end 74 of the corresponding second groove 69, and movement in the left-right direction is restricted. Thereby, the shutter member 42 is held in the open position. When the shutter member 42 moves to the right from the open position, each second protrusion 66 gets over the corresponding second dividing portion 76 and enters the corresponding main portion 72 of the second groove, and can slide in the left-right direction.

  Each of the shutter portions 60 and 61 includes a shielding portion 77 and an opening portion 78 that are formed side by side in the left-right direction that is the sliding direction of the shutter member 42. The shielding part 77 of each shutter part 60, 61 is arranged on the left side of the opening part 78.

  The shielding part 77 of the primary shutter part 60 has a larger area than the inflow port 24 (see FIG. 4) of the case 2 when viewed from the front. The shield part 77 of the secondary shutter part 61 has a larger area than the outlet 25 (see FIG. 4) of the case 2 when viewed from the back.

  As shown in FIG. 3, a finger hook portion 79 protruding forward is formed as an operation portion of the shutter member 42 at the right end portion of the shielding portion 77 of the primary shutter portion 60. As shown in FIG. 8, the finger hook portion 79 protrudes forward from the front surface of the case 2 through the inflow port 24.

  The user can place the shutter member 42 in the closed position or in the open position by placing the finger on the finger hook 79 and moving the shutter member 42 in the left-right direction within the inflow port 24.

  As shown in FIG. 1, when the shutter member 42 is disposed at the closed position, the finger hook portion 79 is disposed at the right end portion of the inflow port 24. The shutter member 42 is restricted from moving in the right direction by the finger hook 79 coming into contact with the right edge of the inflow port 24 of the case 2.

  As shown in FIG. 8, when the shutter member 42 is disposed at the open position, the finger hook portion 79 is disposed at the left end portion of the inflow port 24. The shutter member 42 is restricted from moving in the left direction by the finger hook 79 coming into contact with the left edge of the inflow port 24 of the case 2.

  The opening 78 of the primary shutter unit 60 is configured by a rectangular hole that is slightly smaller than the inflow port 24 when viewed from the front. The opening part 78 of the secondary shutter part 61 shown in FIG. 4 is configured by a rectangular hole that is slightly smaller than the outflow port 25 when viewed from the back.

  When the shutter member 42 is disposed at the closed position shown in FIG. 3, as shown in FIG. 1, the shielding part 77 of the primary side shutter part 60 covers and flows the primary side communication port 54 (see FIG. 8). It arrange | positions in the position which obstruct | occludes the inlet_port | entrance 24. FIG. At this time, the shielding part 77 of the secondary shutter part 61 is disposed at a position that covers the secondary communication port 55 and closes the outlet 25. For this reason, the gas outside the case 2 is prevented from entering the gas detection chamber 46 from the inlet 24 or the outlet 25.

  When the shutter member 42 is disposed at the open position shown in FIG. 7, as shown in FIG. 8, the opening 78 of the primary shutter portion 60 is connected to the primary side communication port 54 and the inflow port 24 when viewed from the front. Duplicate. At this time, the opening 78 of the secondary shutter 61 overlaps with the secondary communication port 55 and the outlet 25 as seen from the back as shown in FIG. Therefore, the inflow port 24 is opened and communicates with the inside of the gas detection chamber 46 through the opening 78 of the primary shutter unit 60 and the primary communication port 54. Further, the outlet 25 is opened, and the inside of the gas detection chamber 46 communicates with the outlet 25 via the opening 78 of the secondary shutter 61 and the secondary communication port 55.

  Normally, the shutter member 42 is disposed at the closed position when the gas detection device 1 is not used, and is disposed at the open position only when the gas detection apparatus 1 is not used. By doing in this way, when not using the gas detection apparatus 1, it can suppress that gas outside case 2 enters the inside of the gas detection chamber 46 from the inflow port 24 and the outflow port 25. FIG. In addition, when the gas detection device 1 is not used, it is possible to prevent liquid such as water from entering the gas detection chamber 46 from the inflow port 24 or the outflow port 25.

  As shown in FIG. 2, the circuit board 10 is disposed in the second region 30 of the case 2. A gas sensor 8 (see FIG. 7), a display device 11, and a control unit are electrically connected to a circuit provided on the circuit board 10.

  FIG. 9 shows the gas sensor 8 of this embodiment. The gas sensor 8 of this embodiment is a semiconductor type gas sensor.

  The gas sensor 8 includes a sensor main body 80 and a cover 81. The sensor body 80 includes a base 83, lead frames 84 to 86 (lead terminals), and a sensor element 87.

  The base 83 is formed from an insulating resin material. The base 83 is formed in a disk shape whose thickness direction is the vertical direction.

  The base 83 is provided with three lead frames 84 to 86 arranged in the left-right direction. Each of the lead frames 84 to 86 has a plate shape extending in the vertical direction. Each of the lead frames 84 to 86 penetrates the base 83 in the vertical direction, and an intermediate portion in the length direction is embedded in the base 83. The upper portions of the lead frames 84 to 86 protrude upward from the base 83, and the lower portions of the lead frames 84 to 86 protrude downward from the base 83.

  The sensor element 87 is supported by lead frames 84 to 86. As shown in FIG. 10, the sensor element 87 includes a pair of electrodes 88 and 89 and a gas sensitive body 90.

  One of the pair of electrodes 88 and 89 is a center electrode 88 and the other is an outer electrode 89. The center electrode 88 and the outer electrode 89 are noble metal wires, and are formed of, for example, a wire made of platinum or a platinum alloy.

  The center electrode 88 has a linear shape extending in the vertical direction, and the lower end is connected to the lead frame 85 as shown in FIG. The outer electrode 89 has a coil shape, and one end is connected to the upper portion of the lead frame 84 and the other end is connected to the upper portion of the lead frame 86.

  As shown in FIG. 10, the coiled outer electrode 89 is disposed around the center electrode 88. The center electrode 88 vertically penetrates the inside of the coiled outer electrode 89.

  The gas sensitive body 90 is provided so that both electrodes 88 and 89 are embedded therein, and is filled between the electrodes 88 and 89. The electrical resistance between the electrodes 88 and 89 disposed with the gas sensitive body 90 interposed therebetween, that is, the electrical resistance of the gas sensitive body 90 varies depending on the concentration of the detection target component.

  By applying a voltage to the outer electrode 89, the outer electrode 89 can generate heat and the gas sensitive body 90 can be heated to a predetermined temperature. In other words, the outer electrode 89 also serves as a heater for heating the gas sensitive body 90.

  As shown in FIG. 9, the cover 81 is formed in a cylindrical shape opened up and down. A base 83 is fitted into the lower opening of the cover 81, and the cover 81 is attached to the base 83 in this state. The sensor element 87 and the upper portions of the lead frames 84 to 86 are arranged in a space surrounded by the cover 81 and the base 83, and are covered with the cover 81 and the base 83.

  Part of the exhaled air that has flowed into the gas detection chamber 46 from the inflow port 24 flows into the cover 81 where the sensor element 87 is located via the upper opening 91 of the cover 81. The upper opening 91 of the cover 81 is preferably provided with a filter 82 that is, for example, a stainless steel wire mesh. The filter 82 captures dust and dirt at the upper opening 91 of the cover 81. For this reason, it is possible to prevent dust and dirt from entering the inside of the cover 81.

  The portions of the lead frames 84 to 86 that protrude downward from the base 83 are connected to the upper end of the circuit board 10 shown in FIG. 7, whereby the gas sensor 8 is mounted on the circuit board 10.

  The cover 81 of the gas sensor 8 protrudes upward from the upper end portion of the circuit board 10. As shown in FIG. 5, the partition part 26 of the case 2 is formed with a through hole 31 penetrating vertically. The through hole 31 is formed by a notch formed in the abutting surface of the front partition piece portion 27 and the rear partition piece portion 28, and is circular.

  The gas sensor 8 (specifically, the cover 81) protrudes from the second region 30 to the first region 29 (see FIG. 2) through the through-hole 31 of the partition 26, and as shown in FIG. It is arranged inside the detection chamber 46.

  As shown in FIG. 5, the through hole 31 is formed in a shape that substantially matches the outer periphery of the cover 81. For this reason, the gas in the gas detection chamber 46 hardly flows out to the second region 30 side from between the cover 81 and the peripheral edge portion of the through hole 31.

  As shown in FIG. 7, the upper opening 91 of the cover 81 of the gas sensor 8 is preferably disposed at a height of ¼ or more and ¾ or less of the height of the gas detection chamber 46. In this way, a part of the exhaled air that has flowed into the gas detection chamber 46 from the inflow port 24 comes into contact with the gas sensor 8 to generate a turbulent flow. An appropriate amount can be introduced into the cover 81 where the sensor element 87 exists through the upper opening 91.

  The display device 11 shown in FIG. 1 is configured by a liquid crystal display, for example. As shown in FIG. 2, the display device 11 is disposed on the front side of the circuit board 10 in the case 2. The control unit is configured by a CPU mounted on the circuit board 10, for example. The control unit and the display device 11 are arranged in the second region 30 together with other electronic components mounted on the circuit board 10. In addition, a battery 12 (see FIG. 1) serving as a power source is disposed in the case 2.

  A window portion 32 is provided on the front plate portion 22 of the front case body 20. The window portion 32 makes the display screen of the display device 11 visible from the front side of the case 2, and is provided at a position facing the display device 11 in the front plate portion 22 of the front case body 20. The window part 32 of this embodiment is comprised with the translucent board which has translucency. The window portion 32 may be a hole provided in the front plate portion 22.

  As shown in FIG. 1, an operation portion 13 is provided on the front plate portion 22 of the front case body 20. The operation unit 13 is located below the window unit 32.

  The operation unit 13 includes a main switch 14 and a sub switch 15. By operating the main switch 14, the user can shift to a menu mode including the start of alcohol concentration measurement or make various decisions. Further, the user can select the menu set in the menu mode by operating the sub switch 15. Moreover, although illustration is abbreviate | omitted, the gas detection apparatus 1 is provided with the speaker which emits a sound as an alerting | reporting part.

  The aforementioned gas sensor 8, display device 11, and speaker are electrically connected to the control unit.

  When the operation unit 13 is operated by the user and a measurement start command is received, the control unit applies a voltage to the outer electrode 89 illustrated in FIG. 9 to heat the gas sensitive body 90 to a predetermined temperature. The heating by the outer electrode 89 is performed until the measurement is completed so as to maintain the predetermined temperature, for example.

  When receiving the measurement start command, the control unit displays the remaining number of uses on the display device 11 shown in FIG. Here, the gas detection device 1 may change its characteristics under the influence of the use environment, and an upper limit value (for example, 1500 times) of the number of times of measurement is determined in advance as a product specification in order to maintain measurement accuracy. For this reason, when the control unit receives the measurement start command, the control unit displays the number of times that the cumulative number of use up to the present is subtracted from the upper limit value as the remaining number of use of the gas detection device 1. Thereby, the user can easily recognize that the number of times of use of the product has reached the upper limit value by checking the remaining number of times of use. In addition, you may display the remaining frequency | count of use of the gas detection apparatus 1 after the measurement of alcohol concentration. Further, in addition to or instead of the remaining number of uses of the gas detection device 1, the cumulative number of uses may be displayed.

  In addition, the control unit informs the user of the timing for driving the speaker and blowing the breath into the inflow port 24. Specifically, the control unit informs the user by a sound emitted from a speaker when a predetermined time has elapsed after receiving the measurement start command. This sound is a sound that represents a countdown such as a time signal, for example, and a forecast sound that is made every predetermined time (for example, 1 second) before the predetermined time elapses from the speaker, and the predetermined time. The correct alarm sound that is made when it has passed is emitted. Note that the timing of inhaling the breath may be notified to the user only by the correct alarm sound, or may be notified to the user by voice or display by the display device 11.

  Further, after the predetermined time has elapsed, the control unit detects the alcohol concentration contained in the expiration using the gas sensor 8. In this detection, for example, the application of the voltage to the outer electrode 89 is intermittently suspended, and a constant voltage is applied to the circuit in which the outer electrode 89, the center electrode 88, and an appropriate resistor are connected in series. This is sometimes done by measuring the amount of voltage drop that occurs between the outer electrode 89 and the center electrode 88. Since the voltage drop varies depending on the change in the electric resistance value of the gas sensitive body 90, it correlates with the concentration of alcohol in the exhaled breath. Then, the control unit calculates the alcohol concentration in the expiration based on the voltage drop amount, displays this on the display device 11, and ends the measurement.

  The gas detection device 1 is used as follows, for example. First, as shown in FIG. 8, the user arranges the shutter member 42 at the open position and opens the inflow port 24 and the outflow port 25. Next, the user operates the operation unit 13 to give an instruction to start measurement. Thereby, the control unit applies a voltage to the outer electrode 89 to heat the gas sensitive body 90 to a predetermined temperature. In addition, the control unit displays the remaining number of uses on the display device 11.

  Then, the user listens to the sound emitted from the speaker and blows into the inflow port 24 of the gas detection device 1 after the predetermined time has elapsed since the measurement start command from the operation unit 13 was received. . This exhaled air passes through the inside of the gas detection chamber 46 and is discharged from the outflow port 25. A part of this exhalation reaches the sensor element 87 in the cover 81 from the upper opening of the gas sensor 8.

  The alcohol concentration by the gas sensor 8 is detected by the user's inhalation, and the result is displayed on the display device 11. And a user arrange | positions the shutter member 42 in the obstruction | occlusion position after completion | finish of a measurement, and obstruct | occludes the inflow port 24 and the outflow port 25. FIG.

  The gas detection device 1 of the present embodiment described above has the following characteristics. The gas detection device 1 includes an inflow port 24, an outflow port 25, a gas sensor 8, a primary side shutter unit 60, and a secondary side shutter unit 61. The sample gas flows from the inlet 24. The sample gas flowing in from the inflow port 24 flows out from the outflow port 25. The gas sensor 8 is disposed in a ventilation space that passes through the inflow port 24 and the outflow port 25, and detects a detection target component contained in the sample gas. The primary shutter 60 closes the inflow port 24 so that it can be opened and closed. The secondary shutter unit 61 interlocks with the primary shutter unit 60 to block the outlet port 25 when the primary shutter unit 60 blocks the inlet port 24, and the primary shutter unit The outlet 25 is opened when 60 is opening the inlet 24.

  The gas detection device 1 having this feature can detect the detection target component contained in the sample gas flowing in from the inflow port 24 by the gas sensor 8. Further, when not in use, the inlet 24 can be closed by the primary shutter 60 and the outlet 25 can be closed by the secondary shutter 61. For this reason, it is possible to suppress the gas sensor 8 from being deteriorated by being exposed to the gas outside the case 2, or the liquid being applied to the gas sensor 8 to cause a failure or the like. In addition, since the primary shutter unit 60 and the secondary shutter unit 61 are interlocked, the user can easily block or open both the inlet port 24 and the outlet port 25 by moving only one shutter unit 60. You can do it.

  Moreover, it is preferable that the gas detection apparatus 1 has the following characteristics like this embodiment. The gas detection device 1 includes a shutter member 42 and a detection chamber forming body 40. The shutter member 42 includes a primary shutter part 60 and a secondary shutter part 61 connected to the primary shutter part 60. The detection chamber forming body 40 includes a gas detection chamber 46 and a shutter member support portion 64. The gas detection chamber 46 communicates with the inflow port 24 and the outflow port 25, and the gas sensor 8 is disposed. The shutter member support part 64 supports the shutter member 42 so as to be slidable between a closed position where the primary shutter part 60 shields the inlet 24 and an open position where the primary shutter part 60 opens the inlet 24. To do.

  In the gas detection device 1 having this feature, the detection chamber forming body 40 having the gas detection chamber 46 also serves as a member that supports the shutter member 42 so as to be slidable. For this reason, the number of parts of the gas detection device 1 can be reduced, and the gas detection device 1 can be downsized.

  Moreover, it is preferable that the gas detection apparatus 1 has the following characteristics like this embodiment. The detection chamber forming body 40 includes an adsorbent storage section (storage chambers 45 and 47) that communicates with the gas detection chamber 46. An adsorbent that adsorbs the detection target component is stored in the adsorbent storage unit.

  The gas detection device 1 having this feature can adsorb the detection target component remaining in the gas detection chamber 46 by the adsorbent disposed in the adsorbent storage unit. For this reason, the measurement accuracy of the gas sensor 8 can be improved and the deterioration of the gas sensor 8 can be suppressed. Moreover, since the detection chamber forming body 40 also serves as a member for storing the adsorbent, the number of parts of the gas detection device 1 can be further reduced, and the gas detection device 1 can be further downsized.

  In the present embodiment, the primary shutter unit 60 and the secondary shutter unit 61 are integrally formed, but the primary shutter unit 60 and the secondary shutter unit 61 may be separate. . In this case, the primary side shutter unit 60 and the secondary side shutter unit 61 are connected via, for example, an interlocking mechanism, whereby the primary side shutter unit 60 and the secondary side shutter unit 61 are connected by the inlet 24 and the flow path. The state where the outlet 25 is closed and the state where the inlet 24 and the outlet 25 are opened are switched.

  The shutter member 42 of the present embodiment is slidably supported by a detection chamber forming body 40 having a gas detection chamber 46 and an adsorbent storage portion (storage chambers 45 and 47). You may be slidably supported by the member which has only any one among adsorption agent accommodating parts. The shutter member 42 may be slidably supported by a member that does not have any of the gas detection chamber 46 and the adsorbent storage portion.

  In addition, the design of the gas detection device 1 of the present embodiment can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Gas detection apparatus 24 Inflow port 25 Outflow port 40 Detection chamber formation body 42 Shutter member 45 Storage chamber (adsorbent storage part)
46 Gas detection chamber 60 Primary shutter part 61 Secondary shutter part 64 Shutter member support part 8 Gas sensor

Claims (3)

A gas sensor for detecting a detection target component contained in the sample gas; and
A primary communication port formed on the front surface through which the sample gas flows; a secondary communication port formed at a position facing the primary communication port on the rear surface; A gas detection chamber having a through-hole into which the gas sensor is inserted, and
A storage chamber that is disposed adjacent to the gas detection chamber through a partition wall having a through hole, and that stores an adsorption member that adsorbs the gas present in the gas detection chamber;
A primary shutter portion covering the primary side communication port so as to close the secondary side communication port; a secondary shutter portion covering the secondary side communication port so as to close; the primary side shutter portion and the secondary side shutter. And a connecting portion that connects the primary shutter portion and the secondary shutter portion so that the primary side communicating port and the secondary side communicating port are simultaneously opened and closed. A gas detection device comprising a shutter member. The gas sensor includes a cover;
The gas detection device according to claim 1, wherein the through hole has a shape along an outer periphery of the cover. An inlet corresponding to the primary side communication port and an outlet corresponding to the secondary side communication port, further comprising a case covering the shutter member;
The primary shutter portion includes a finger hook portion that protrudes outward from the inflow port and moves in the left-right direction;
When the finger hook is disposed at one edge of the inflow port, the primary side communication port and the secondary side communication port are opened, and the finger hook is disposed at the other edge of the inflow port. 3. The gas detection device according to claim 1, wherein the primary side communication port and the secondary side communication port are closed when the gas is discharged.

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