JP4968154B2 - Alcohol concentration meter - Google Patents

Description

  The present invention relates to an alcohol concentration measuring instrument, and more particularly to an alcohol concentration measuring instrument that measures an alcohol concentration contained in a breath of a subject.

  As this type of alcohol concentration measuring instrument, a type that is mounted on a vehicle and in which a subject blows breath on an alcohol sensor through a blowing port is known (see, for example, Patent Document 1 below). When such an alcohol concentration measuring device is used, when the subject (driver) is in a drinking state (drinking state) and the measured alcohol concentration is equal to or higher than a set value, for example, the engine cannot be started. It is possible to prevent drunk driving well.

Japanese Patent Laying-Open No. 2005-74162

  However, in the alcohol concentration measuring instrument described in Patent Document 1, the distance between the air inlet and the subject is not considered when detecting the alcohol concentration, and the distance between the air inlet and the subject is not considered. First, since the alcohol concentration is measured, there is a problem that an error is likely to occur in the measured alcohol concentration.

  The present invention has been made to cope with the above problem, and an object of the present invention is to provide an alcohol concentration measuring device in which an error does not easily occur in the measured alcohol concentration.

In order to achieve the above object, an alcohol concentration measuring instrument according to the present invention includes an alcohol sensor that detects an alcohol concentration contained in exhaled breath of a subject blown into a blowing port, and a distance sensor that detects a distance between the blowing port and the subject. the provided, distance detected by the distance sensor is a condition that is within the predetermined distance, it is assumed to perform an alcohol concentration detection by the alcohol sensor.

In the alcohol concentration measuring device having the above premise configuration , alcohol concentration detection is performed on the condition that the distance detected by the distance sensor is within a predetermined distance. For this reason, when the distance detected by the distance sensor exceeds the predetermined distance, the alcohol concentration detection process is not completed, and it is not possible to shift to a process for determining whether to start the subsequent vehicle. Accordingly, the subject inhales exhaled breath within the predetermined distance from the suction port, so that an error does not easily occur in the measured alcohol concentration.

The present invention, in addition to the above premise construction, distance detected by the distance sensor is characterized in that it comprises a notifying means for informing the subject that exceeds a predetermined distance. According to this, a test subject can be made to recognize favorably that it is in the state where alcohol concentration is not measured appropriately.

In the above premise construction, the alcohol concentration measuring devices are provided with a portable case blowing breath close subject to the mouth, the alcohol sensor and the distance sensor is equal to or built into the case. According to this, the alcohol concentration measuring instrument which achieves the above-described object can be configured in a compact manner.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an alcohol concentration measuring device according to the present invention, FIG. 2A is a front view of the alcohol concentration measuring device, and FIG. This alcohol concentration measuring instrument is of a portable type (handy type) that blows inhaled air close to the mouth of the subject U, and includes an alcohol sensor 21, a measurement start switch 22, a distance sensor 23, a sound generator incorporated in the case 10. 24, the display 25, and sensor ECU31 connected with these via a harness.

  The front wall 11 of the case 10 is formed with a blowing port 11a, and the back wall 12 of the case 10 is formed with a blowing port 12a substantially coaxially with the blowing port 11a. An exhalation flow path P is formed so that exhaled air blown into the mouth 11a is blown out through the blowout port 12a.

  The alcohol sensor 21 includes a sensor unit 21a and a substrate 21b. The alcohol sensor 21 is incorporated in the case 10 so that the substrate 21b forms part of the exhalation flow path P, and the sensor unit 21a protrudes toward the exhalation flow path P. Has been placed. The sensor unit 21a is a semiconductor sensor formed by coating a metal coil such as tin oxide on a platinum coil, for example. When the sensor unit 21a is heated to a predetermined temperature by energization of the substrate 21b, alcohol molecules are adsorbed on the surface, and the electric resistance value of the sensor unit 21a changes. The sensor unit 21a outputs the electrical resistance value at this time to the sensor ECU 31. The alcohol sensor 21 is not limited to a semiconductor sensor, and for example, a sensor using a change in electromotive force due to an electrochemical reaction or a sensor using a characteristic that alcohol vapor molecules absorb infrared rays of a specific wavelength may be used. Good.

  The measurement start switch 22 is, for example, a mechanical switch that switches on and off of the contact, and is disposed on the front wall 11 of the case 10 so as to protrude outward. The contact of the measurement start switch 22 is turned on by a downward displacement (a direction toward the inside of the case 10), and the contact is turned off by an upward displacement (a direction toward the outside of the case 10). When the measurement start switch 22 is turned on, the alcohol sensor 21 is activated.

  The distance sensor 23 is, for example, an infrared sensor, and reflects reflected light to the subject U by projecting infrared light to the outside through an opening hole 11 b formed in the vicinity of the blowing port 11 a on the front wall 11 of the case 10. The electrical resistance value that changes in accordance with the light receiving position is output to the sensor ECU 31. Note that the distance sensor 23 is not limited to the infrared sensor, and may be, for example, a sensor that uses natural light, or a sensor that measures a time until a reflected wave by ultrasonic waves is received and converts it into a distance.

  The sound generator 24 (notification means) is, for example, a buzzer, and notifies the subject of the measurement state with sound. Specifically, when the distance between the subject U and the air inlet 11a is within a predetermined distance (for example, 10 cm) and the sensor ECU 31 can measure the alcohol concentration with high accuracy, the sound generator 24 is, for example, “Pippi”. , Etc., repeatedly produces a short sound. On the other hand, when the distance between the subject and the air inlet 11a exceeds a predetermined distance (for example, 10 cm) and the sensor ECU 31 cannot measure the alcohol concentration with high accuracy, the sound generator 24 is, for example, “pea” or the like. , Generate a long sound without turning off the sound. Note that the sound generator 24 is not limited to a buzzer, and may output sound based on sound data stored in advance in a memory using, for example, a sound synthesis circuit and a speaker.

  The display device 25 is, for example, an LED display, and displays the calculated measurement value of the alcohol concentration. The display device 25 is arranged on the front wall 11 of the case 10 in a manner that is visible from the outside.

  The sensor ECU 31 includes a microcomputer including a CPU, a ROM, a RAM, a memory, an I / O and the like as main components, and repeatedly executes the alcohol concentration measurement program of FIG. 3 stored in the ROM. The sensor ECU 31 functions as an alcohol concentration calculation means for calculating the alcohol concentration based on the sensor signal from the alcohol sensor 21 and drives and controls the sound generator 24 according to the distance detected by the distance sensor 23. .

  Next, the operation of the embodiment configured as described above will be described using the alcohol concentration measurement program of FIG. When the subject U turns on the measurement start switch 22, the alcohol sensor 21 is activated (S11). If the subject U brings the case 10 close to his / her mouth and the distance between the subject U and the blowing port 11a is within a predetermined distance (S12: Yes), the sensor ECU 31 has a short length such as “beep” on the sound generator 24, for example. Is repeatedly generated (S14).

  In this state, when the subject U blows breath on the alcohol sensor 21 through the blowing port 11a, the alcohol sensor 21 outputs a sensor signal (electric resistance value) corresponding to the alcohol concentration contained in the breath to the sensor ECU 31. Then, the sensor ECU 31 calculates the alcohol concentration based on this sensor signal (S15). When the calculation of the alcohol concentration is completed (S16: Yes), the drive control of the sound generator 24 is stopped (S17), and the measured value of the alcohol concentration is displayed on the display 25 (S18). The sensor ECU 31 causes the sound generator 24 to repeatedly generate a short-length sound until the calculation of the alcohol concentration is completed (S16: No).

  On the other hand, if the distance between the subject U and the air inlet 11a exceeds a predetermined distance (for example, 10 cm) (S12: No), the sensor ECU 31 does not turn off the sound such as “Pee” or the like to the sound generator 24. A long sound is generated (S13). As a result, the subject U can recognize well that the alcohol concentration is not properly measured, so that the case 10 is brought closer to the mouth and the exhalation is blown until the distance from the blowing port 11a is within a predetermined distance. Therefore, an error is less likely to occur in the measured alcohol concentration.

  Moreover, in the said embodiment, since it comprised so that the sound generator 24 might generate | occur | produce the sound of a different aspect by the case where the distance of the test subject U and the blowing port 11a is less than predetermined distance, and the case where it exceeds predetermined distance, measurement The situation can be easily recognized by the subject U.

  In the above embodiment, the case where the present invention is applied to a movable alcohol concentration measuring device has been described. However, the stationary alcohol concentration measuring device, that is, the alcohol concentration measuring device is on the vehicle body side, such as an instrument panel or a steering wheel. You may apply to the type fixed to a wheel.

The block diagram of the alcohol concentration measuring device which concerns on this invention. (A) is a front view of an alcohol concentration measuring instrument, (b) is an AA cross-sectional view of (a). The flowchart which shows the alcohol concentration measurement program performed by sensor ECU of FIG.

Explanation of symbols

10 Case 11a Inlet 12a Outlet P Expiratory flow path 21 Alcohol sensor 22 Measurement start switch 23 Distance sensor 24 Sound generator (notification means)
25 Display 31 Sensor ECU

Claims (3)

An alcohol sensor for detecting the alcohol concentration contained in the exhaled breath of the subject blown into the breathing opening;
A distance sensor for detecting the distance between the inlet and the subject;
The alcohol concentration is detected by the alcohol sensor on the condition that the distance detected by the distance sensor is within a predetermined distance ,
Furthermore, the alcohol concentration measuring device is provided with an informing means for informing the subject that the distance detected by the distance sensor exceeds the predetermined distance . An alcohol sensor for detecting the alcohol concentration contained in the exhaled breath of the subject blown into the breathing opening;
A distance sensor for detecting the distance between the inlet and the subject;
The alcohol concentration is detected by the alcohol sensor on the condition that the distance detected by the distance sensor is within a predetermined distance,
The alcohol concentration measuring instrument has a portable case in which a subject blows in breaths close to the mouth, and the alcohol sensor and the distance sensor are incorporated in the case. . 2. The alcohol concentration measurement according to claim 1 , wherein the alcohol concentration measuring device has a portable case in which a test subject blows into the mouth close to the mouth, and the alcohol sensor and the distance sensor are incorporated in the case. vessel.

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