Microphone for testing alcohol

Abstract

The invention belongs to the technical field of alcohol detection, and discloses an alcohol testing microphone. The alcohol testing microphone comprises a microphone shell, an air inlet and an air outlet are formed in the top and the bottom of the microphone shell respectively, the alcohol testing microphone further comprises two electrode plates arranged in the microphone shell, a vibrating membrane is arranged between the two electrode plates, the distance between the two electrode plates can be changed through vibration of the vibrating membrane, a gas sensitive resistor is further arranged in the microphone shell, and the gas sensitive resistor is electrically connected with the gas sensitive resistor. And the resistance value of the gas sensitive resistor in contact with alcohol changes. According to the alcohol testing microphone, airflow is used for driving the vibrating diaphragm to generate kinetic energy, the kinetic energy is converted into an electric signal, the resistance value change of the gas sensitive resistor serves as a unique variable, the electric signal output by the resistance value is in positive correlation with the alcohol concentration, the alcohol concentration of exhaled gas can be visually reflected, meanwhile, the technical scheme achieves the miniaturization design, and the cost is low. The mobile phone shell can be used as an accessory of a mobile phone, a microphone, an interphone and the like, is convenient to carry and low in production cost, and solves the problems in the background technology.

Description

Technical Field

[0001] The invention relates to the technical field of alcohol detection, in particular to an alcohol testing microphone. Background Art

[0002] With the continuous development of society, the number of cars has increased sharply, and material life has become more and more abundant. The situation of drunk driving needs to be taken more seriously. Don't drink before driving, don't drive after drinking. Based on similar circumstances, many car owners will buy some alcohol detectors by themselves through online or offline purchases. They are mainly used for testing for a long time after drinking to determine whether there is still alcohol in their body, such as drinking the night before and driving the next day;

[0003] However, most of the current alcohol testing products appear as independent devices, and the battery life of the device needs to be considered during use. The portable device also has a strong sense of presence, making it difficult to achieve true portability and not conducive to cost control. Summary of the invention

[0004] The purpose of the invention is to provide an alcohol testing microphone, which realizes a miniaturized design and exists as an accessory. The detection principle is simple, which is helpful for cost control and product popularization, and solves the problems raised in the background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: an alcohol testing microphone, comprising a microphone shell, wherein the top and bottom of the microphone shell are respectively provided with an air inlet and an air outlet;

[0006] Also includes two electrode sheets arranged in the microphone housing;

[0007] A vibration membrane is arranged between the two electrode sheets, and the vibration of the vibration membrane can change the distance between the two electrode sheets;

[0008] There is also a gas-sensitive resistor inside the microphone housing, and the resistance value of the gas-sensitive resistor changes when it comes into contact with alcohol.

[0009] One of the electrode sheets and one pin of the gas sensor is grounded, and the other pin of the gas sensor and the other electrode sheet are connected to an amplifier circuit. The change in the distance between the two electrode sheets causes the capacitance of the capacitor to change to output an electrical signal. The change in the resistance value of the gas sensor causes the change in the current or voltage in the amplifier circuit to reflect the alcohol content in the exhaled gas.

[0010] By adopting the above technical solution, the beneficial effects of the present invention are:

[0011] The alcohol testing microphone is different from the working mode of traditional alcohol detectors. The device uses airflow to drive the vibration membrane to generate kinetic energy and convert it into an electrical signal. The resistance value change of the gas-sensitive resistor is used as the only variable. The electrical signal output by the resistance value is positively correlated with the alcohol concentration, and can intuitively reflect the alcohol concentration of the exhaled gas. At the same time, the technical solution realizes a miniaturized design and can be used as an accessory for mobile phones, microphones, walkie-talkies, etc. It is easy to carry and has a low production cost, which solves the problems raised in the background technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structure of the present invention;

[0013] Figure 2 This is the amplification circuit diagram of the present invention.

[0014] In the picture: 1 microphone housing, 2 air inlet, 3 air outlet, 4 electrode sheet, 5 vibration membrane, 6 gas sensor. DETAILED DESCRIPTION

[0015] See also Figure 1-2 The present invention provides a technical solution: a microphone for testing alcohol, comprising a microphone housing 1, wherein an air inlet 2 and an air outlet 3 are respectively provided at the top and the bottom of the microphone housing 1;

[0016] It also includes two electrode sheets 4 arranged in the microphone housing 1;

[0017] A vibration membrane 5 is arranged between the two electrode sheets 4, and the vibration of the vibration membrane 5 can change the distance between the two electrode sheets 4;

[0018] A gas-sensitive resistor 6 is also provided in the microphone housing 1, and the resistance value of the gas-sensitive resistor 6 changes when it contacts alcohol;

[0019] One of the electrode sheets 4 and one pin of the gas-sensitive resistor 6 are grounded, and the other pin of the gas-sensitive resistor 6 and the other electrode sheet 4 are connected to the amplifier circuit. The change in the distance between the two electrode sheets 4 causes the capacitance of the capacitor to change to output an electrical signal. The change in the resistance value of the gas-sensitive resistor 6 causes the change in the current or voltage in the amplifier circuit to reflect the alcohol content in the exhaled gas.

[0020] When a person ingests alcohol, the alcohol will be absorbed by the body and enter the blood, and then exhaled through the lungs. The alcohol concentration in the exhaled gas has a certain proportional relationship with the alcohol concentration in the blood. Therefore, the alcohol content in the blood can be estimated by detecting the alcohol concentration in the exhaled gas. Specifically, the gas sensor 6 will undergo an oxidation-reduction reaction when encountering alcohol, resulting in a change in resistance value. The higher the alcohol concentration in the exhaled gas, the greater the change in resistance value of the gas sensor, thereby causing changes in current and voltage in the circuit.

[0021] See also Figure 2, the attached figure is the amplifying circuit of the alcohol microphone; IC1A of YDL Jinyu 358 is the amplifier group of the alcohol microphone, which is composed of R1 and R2, R4, R6, R3, and R5. The voltage between R1 and R2 is the reference voltage. Pin 2 of IC1A is the voltage change of the alcohol microphone. When it is higher than the voltage of pin 3 of IC1A, the voltage of pin 1 of IC1A flips to a high level, indicating that the gas-sensitive resistor in the microphone at the R end is affected by the alcohol content.

[0022] IC1B of YDL Golden Domain 358 is the microphone amplifier group, which is composed of R7, R8, R9, R11, R10, C1, C2 and CE1. The voltage between R7 and R8 is the reference voltage. Pin 2 of IC1 B is the voltage of the microphone. When it changes to a higher voltage than pin 7 of IC1 B, the voltage of pin 7 of IC1 B flips to a high level, indicating that the diaphragm in the microphone at the C end is subjected to sound pressure.

[0023] When the alcohol testing microphone is used, the microphone is installed on a smart phone, and a matching APP is installed to analyze the current and voltage values ​​output by the alcohol testing microphone and convert them into alcohol content. Air is blown through the air inlet 2 of the microphone housing 1, and the high-speed flowing gas is discharged from the air outlet 3 through the vibrating membrane 5 and the gas-sensitive resistor 6. The airflow sound waves drive the vibrating membrane 5 to vibrate and change the distance between the two electrode sheets 4. The change in distance causes the capacitance of the capacitor to change, thereby generating an electrical signal. When the blown gas does not contain alcohol, the resistance value of the gas-sensitive resistor 6 does not change, and the alcohol microphone outputs a stable current and voltage through the amplifying circuit. When the blown gas contains alcohol, the gas-sensitive resistor 6 undergoes an oxidation-reduction reaction with the alcohol, causing its resistance value to change. The higher the alcohol concentration in the exhaled gas, the greater the change in the resistance value of the gas-sensitive resistor, thereby causing changes in the current and voltage in the circuit to feedback the alcohol content of the blown gas.

[0024] Various modifications to these embodiments will be apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A microphone for testing alcohol, comprising a microphone housing (1), characterized in that: The top and bottom of the microphone housing (1) are respectively provided with an air inlet (2) and an air outlet (3); It also includes two electrode sheets (4) arranged in the microphone housing (1); A vibration membrane (5) is arranged between the two electrode sheets (4), and vibration of the vibration membrane (5) can change the distance between the two electrode sheets (4); A gas-sensitive resistor (6) is also arranged in the microphone housing (1), and the resistance value of the gas-sensitive resistor (6) changes when it contacts alcohol; One of the electrode sheets (4) and one pin of the gas-sensitive resistor (6) is grounded, and the other pin of the gas-sensitive resistor (6) and the other electrode sheet (4) are connected to an amplifier circuit. The distance between the two electrode sheets (4) changes so that the capacitance of the capacitor changes to output an electrical signal. The change in the resistance value of the gas-sensitive resistor (6) causes a change in the current or voltage in the amplifier circuit to reflect the alcohol content in the exhaled gas.

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