A portable alcohol detector

Abstract

The utility model relates to a kind of portable alcohol detector, including shell, shell inside is provided with PCB, and pressure sensor, electrochemical sensor, air pump, power supply and controller are integrated on PCB, main channel is also provided in shell, and pressure detection channel is connected to main channel, the gas outlet end of pressure detection channel is connected with pressure sensor, sampling wine channel is also connected to main channel, electrochemical sensor and air pump are arranged in sampling wine channel, controller is connected with pressure sensor, air pump and electrochemical sensor signal, the upper end of shell is equipped with the gas nozzle connected with main channel, the gas outlet end of main channel is extended outward after passing through shell, the gas inlet end of the sampling wine channel is inserted into main channel, and it is extended in the direction of the gas outlet end of main channel. Ensure the accuracy of each measurement, improve the test efficiency of single sampling.

Description

Technical Field

[0001] This utility model relates to the field of alcohol detection technology for train attendants, and in particular to a portable alcohol detector. Background Technology

[0002] Train attendants are required to undergo alcohol testing before starting their shifts to ensure train safety. However, previous testing methods were not efficient. In the past, alcohol testing for train attendants used diffusion and suction sensors. Currently, the method used for suction testing of train attendants is an electromagnet combined with an airbag. This method is simple in principle, but after each test, a small amount of gas remains in the airbag. Over time, this can easily cause the airbag to corrode and rupture, which in turn corrodes the circuit board and causes a short circuit. In addition, this method is also expensive.

[0003] There are many existing methods for testing alcohol levels by train attendants. Most of these products share a similar circuit principle, including a signal pressure sensor, signal processing module, air extraction module, electrochemical sensor module, power supply, and control module. The main areas for improvement lie in the air extraction method and the selection of the electrochemical sensor, as the extraction speed and volume, as well as the reaction speed of the electrochemical sensor, directly affect the accuracy and speed of the alcohol test. Currently, the internal flow channel design of alcohol detectors allows some gas to easily enter the electrochemical sensor module before the pressure sensor provides a feedback signal, thus affecting the efficiency and accuracy of single-measurement alcohol tests. Utility Model Content

[0004] The purpose of this invention is to provide a portable alcohol detector to solve the problems of insufficient measurement accuracy and inadequate structural protection in existing alcohol detectors.

[0005] To solve the above problems, the portable alcohol detector involved in this utility model adopts the following technical solution:

[0006] A portable alcohol detector includes a housing with a PCB board inside. The PCB board integrates a pressure sensor, an electrochemical sensor, a vacuum pump, a power supply, and a controller. The housing also has a main channel with a pressure detection channel connected to it. The outlet of the pressure detection channel is connected to the pressure sensor. The main channel also has a sampling and alcohol testing channel connected to it. The electrochemical sensor and the vacuum pump are arranged in the sampling and alcohol testing channel. The controller is connected to the pressure sensor, the vacuum pump, and the electrochemical sensor. The upper end of the housing has a nozzle connected to the main channel. The outlet of the main channel extends outward after passing through the housing. The inlet of the sampling and alcohol testing channel is inserted into the main channel and extends in the same direction as the outlet of the main channel.

[0007] Furthermore, the upper rear side of the housing is provided with an air outlet, the main channel extends downward and then bends backward to connect to the air outlet, and the air inlet of the sampling and alcohol testing channel is connected to the side of the main channel and inserted backward into the air inlet.

[0008] Furthermore, the air inlet of the pressure detection channel is connected to the side wall of the main channel, and the air inlet of the pressure detection channel is higher than the height of the air outlet.

[0009] Furthermore, an exhaust port communicating with an air pump is provided on the lower rear side of the housing.

[0010] Furthermore, the lower end of the housing is provided with an aviation plug for connecting to an external display device. The aviation plug has a power connector for connecting to a power source and a communication connector for connecting to a communication port on the PCB board.

[0011] Furthermore, the air pump is a vacuum pump.

[0012] The beneficial effects of this utility model are as follows: Compared with the prior art, the portable alcohol detector involved in this utility model, based on the principle of airflow dynamics, rationally designs the connection position between the sampling and alcohol testing channel and the main channel, as well as the position of the gas collection, thereby possessing an active sampling function; that is to say, the gas must first be detected by the pressure sensor before the pump is controlled to actively draw a very small amount of gas from the downward airflow into the electrochemical sensor. This ensures that the amount of gas drawn by the pump is determined to be the amount of gas in one pump operation, satisfying the requirement that there is basically no residual amount after the combustion reaction of the electrochemical sensor in a single measurement, ensuring the accuracy of each measurement, and improving the testing efficiency of a single sampling. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly described below:

[0014] Figure 1 This is a schematic diagram of a specific embodiment of the portable alcohol detector of this utility model;

[0015] Figure 2 for Figure 1 Top view;

[0016] Figure 3 for Figure 1 A half-section view;

[0017] Figure 4 for Figure 3 Sectional view along direction A;

[0018] Figure 5 for Figure 3 The operating logic block diagram of the detector.

[0019] Explanation of reference numerals in the attached drawings: 1-Housing; 101-Front housing; 102-Rear housing; 2-Blow nozzle; 3-Aviation plug; 4-Outlet; 5-Exhaust port; 6-PCB board; 7-Pressure sensor; 8-Electrochemical sensor; 9-Air pump; 10-Main channel; 11-Pressure detection channel; 12-Inlet section; 13-Transition section; 14-Exhaust section. Detailed Implementation

[0020] To make the technical objectives, technical solutions, and beneficial effects of this utility model clearer, the technical solution of this utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0021] The specific embodiment of the portable alcohol detector involved in this utility model is shown in the figure. The portable alcohol detector is a complete alcohol testing head. The alcohol testing head is powered and can independently complete the alcohol testing work. With the help of an external display device, the test structure can be displayed. The internal circuit function principle is basically similar to the alcohol detectors on the market. However, the specific electronic components and circuit design are all independently selected and designed. The product has been specifically verified in the field and is a mature product. The test results are all obtained through specific verification.

[0022] The alcohol measuring head includes a housing 1, which includes a front shell 101 and a rear shell 102 that are fastened to each other in the front-to-back direction and are sealed together. The housing 1 has a small bottle-shaped structure. The overall dimensions of the housing 1 are approximately 110mm in length, 70mm in width, and 28mm in thickness. It is small, exquisite, easy to carry, and quick to install.

[0023] The top of the housing 1 is connected to an air nozzle 2 for blowing air into the housing 1; the bottom of the housing 1 is connected to a 7-pin aviation connector 3, which supplies power to the internal alcohol testing module via an external 5V power supply and communicates with the display device via a serial port to effectively display the test results. The upper part of the rear side wall of the rear housing 102 has an air outlet 4, which corresponds to the air nozzle 2. Most of the air blown into the housing 1 by personnel is directly discharged through the air outlet 4.

[0024] The housing 1 contains a PCB board 6, which is detachably laid on the rear housing 102. To ensure the stability and reliability of the internal PCB board 6, electronic components are carefully arranged only in the upper half of the rear housing 102, and the lower half is basically unsoldered to prevent the bottom of the components from getting damp and short-circuiting, which facilitates subsequent maintenance and fault inspection.

[0025] The PCB integrates a pressure sensor 7, an electrochemical sensor 8, a vacuum pump 9, a power supply, and a controller. The controller is connected to the pressure sensor 7, the electrochemical sensor 8, the vacuum pump 9, etc., to receive the corresponding sampling signals and output the corresponding control signals.

[0026] A main channel 10 is connected between the air nozzle 2 and the air outlet 4. In this embodiment, the main channel 10 is made of silicone tubing. The main channel 10 is relatively short and is only integrated on the top of the rear shell 102. The main channel 10 extends downward after passing through the air nozzle 2 and then bends backward to connect to the air outlet 4 to exhaust air outward.

[0027] A pressure detection channel 11 is connected to the main channel 10. The outlet of the pressure detection channel 11 is connected to the pressure sensor 7, and the inlet of the pressure detection channel 11 is connected to the side wall of the main channel 10. The inlet of the pressure detection channel 11 is higher than the outlet 4. Specifically, the pressure detection channel 11 is also made of silicone tubing. The inlet of the pressure detection channel 11 is close to the top of the rear shell 102 and is sealed and plugged into the side wall of the main channel 10. A pressure sensor 7 connected to the PCB board 6 is set on the side of the main channel 10 to detect the gas pressure entering the main channel 10.

[0028] A sampling and wine testing channel is also connected to the main channel 10. An electrochemical sensor 8 and a vacuum pump 9 are arranged in the sampling and wine testing channel, with the electrochemical sensor 8 located upstream of the vacuum pump 9. The air inlet of the sampling and wine testing channel is inserted into the main channel 10 and extends in the same direction as the air outlet of the main channel 10.

[0029] Specifically, the sampling and alcohol testing channel includes an air inlet section 12 arranged on the side of the main channel 10 facing away from the pressure sensor 7, a transition section 13 connecting the electrochemical sensor 8 and the vacuum pump 9, and an exhaust section 14 connected to the exhaust end of the vacuum pump 9. In order to meet the independent air inlet and outlet of the vacuum pump 9, an exhaust port 5 communicating with the vacuum pump 9 is provided on the lower rear side of the housing 1.

[0030] Among them, the above-mentioned vacuum pump 9 is a custom-made Time Electronics SC3101PM_DC3.3V vacuum pump. The specific structure of the vacuum pump is not described in detail. When the vacuum pump is powered on (DC6.0V / 4.5V), the rubber diaphragm inside it reciprocates, thereby compressing and stretching the air in the pump chamber, forming a vacuum at the air inlet end of the bottom cover (13). When the vacuum pump stops being powered, the motor stops running, and the remaining vacuum at the air inlet end is released through the vent valve. This air pump meets the requirements for single-sample gas extraction and can operate continuously. When used together, the results of a single sampling test can be completed in 2.4 seconds, and in about 2.2 seconds for alcohol content, thus speeding up the single-sample quantitative testing for train crew members. The vacuum pump has independent air inlet and outlet ports 4, so there is no need to worry about excess gas remaining. After fatigue testing, it remains stable and reliable with no gas residue. In actual use, the solution has been verified to be stable and efficient, improving the efficiency of single-sample quantitative testing for train crew members when taking alcohol tests.

[0031] Meanwhile, to meet the functions of accurate and active sampling, the main channel 10 extends downward and then bends backward to connect to the air outlet 4. The air inlet of the sampling and measuring channel is connected to the side of the main channel 10 and inserted backward into the air inlet. This arrangement ensures that the orientation of the air inlet of the air inlet section 12 is consistent with the orientation of the air outlet 4. Based on the principles of airflow dynamics, the position of the gas pipeline and the position of the collected gas are rationally designed, thus enabling active sampling. Only when the vacuum pump is working can a very small amount of gas in the downward-flowing airflow be actively drawn into the electrochemical sensor 8. This ensures that the amount of gas drawn by the pump is the amount for one pump operation, which meets the requirement that there is basically no residual amount after the combustion reaction of the electrochemical sensor 8 in a single measurement, thus ensuring the accuracy of each measurement.

[0032] In actual operation, the air inlet of the sampling and testing channel extends into the air outlet 4 of the main channel 10. During normal testing, a breath is blown into the main channel 10, and the airflow passes through the air nozzle 2 and flows downward and backward through the main channel 10. During this process, since the side interface of the pressure detection channel 11 is closest to the air nozzle 2, the gas first reaches the pressure sensor 7. When the pressure sensor 7 detects a certain pressure value, it feeds back to the controller. The controller then controls the vacuum pump to pump air. Since the air inlet of the electrochemical sensor 8 is below the main channel 10, a very small amount of gas can be drawn from the airflow into the electrochemical sensor 8. The drawn gas reacts in the electrochemical sensor 8 (excess gas is discharged from the vacuum pump outlet) and is processed by the analog front-end chip. The processed data is then communicated with the CPU, and the CPU receives the data, calculates it, and draws a conclusion.

[0033] The ingenious design of this gas flow system lies in the rational design of the gas pipeline and gas collection location based on the principles of airflow dynamics, thereby enabling active sampling. In other words, the gas must first be detected by the pressure sensor 7 before the vacuum pump is controlled to actively draw a very small amount of gas from the downward-flowing airflow into the electrochemical sensor 8. This ensures that the amount of gas drawn by the pump is the amount for one pump operation, satisfying the requirement that there is basically no residual amount after the combustion reaction of the electrochemical sensor 8 in a single measurement, thus ensuring the accuracy of each measurement.

[0034] The overall working principle block diagram is as follows: Figure 5 As shown: When air is blown, the pressure sensor 7 senses a certain pressure value and feeds it back to the controller. The controller then controls the vacuum pump to pump air. The pumped air is processed by the electrochemical sensor 8 and the simulation front end. The processing result is communicated with the controller. The data information received by the controller is processed and communicated with the display device for display.

[0035] Finally, it should be noted that the above embodiments are only for illustration and not for limiting the technical solutions of this utility model. Any equivalent substitutions and modifications or partial substitutions that do not depart from the spirit and scope of this utility model should be covered within the scope of protection of the claims of this utility model.

Claims

1. A portable alcohol detector characterized by, The shell is internally provided with a PCB, the PCB is integrated with a pressure sensor, an electrochemical sensor, a suction pump, a power supply and a controller, the shell is further internally provided with a main channel, the main channel is connected with a pressure detection channel, the outlet end of the pressure detection channel is connected with the pressure sensor, the main channel is further connected with a sampling and wine testing channel, the electrochemical sensor and the suction pump are arranged in the sampling and wine testing channel, the controller is signal connected with the pressure sensor, the suction pump and the electrochemical sensor, the upper end of the shell is provided with a blowing nozzle connected with the main channel, the outlet end of the main channel extends outward after penetrating through the shell, the inlet end of the sampling and wine testing channel is inserted into the main channel and extends in the same direction towards the outlet end of the main channel.

2. The portable alcohol detection instrument of claim 1, wherein, The upper rear side of the shell is provided with an air outlet hole, the main channel extends downward and then bends rearward to connect the air outlet hole, the inlet end of the sampling and wine testing channel is connected to the side of the main channel and is inserted into the air outlet hole rearward.

3. The portable alcohol detection instrument of claim 2, wherein, The inlet end of the pressure detection channel is connected to the side wall of the main channel, and the inlet end of the pressure detection channel is higher than the height of the air outlet hole.

4. The portable alcohol detection instrument of claim 2, wherein, The lower rear side of the shell is provided with an air exhaust hole in communication with the suction pump.

5. The portable alcohol detection instrument of claim 1, wherein, The lower end of the shell is provided with an aviation plug for connecting with an external display device, the aviation plug has a power supply connector for connecting with the power supply and a communication connector for connecting with the communication port on the PCB.

6. The portable alcohol detection instrument of claim 1, wherein, The suction pump is a vacuum pump.

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