CN107007961A - A kind of fire extinguisher of adjustable acoustic pressure size - Google Patents

Abstract

The invention relates to a fire extinguisher with adjustable sound pressure, which includes a power supply, a signal generator, a power amplifier and a loudspeaker, the power supply is used to provide power for the fire extinguisher; the signal generator is used to generate a low-frequency square wave analog signal, and through Adjust the frequency of the signal to achieve the purpose of changing the voltage; the power amplifier is used to amplify the low-frequency square wave analog signal without distortion; the sounding end of the speaker is equipped with a sound cavity; the speaker converts the amplified low-frequency square wave The analog signal is converted into a sound wave for playing; the sound cavity is used for directional gathering of the sound wave played by the speaker. The invention can adjust the sound pressure and improve the fire extinguishing effect.

Description

A fire extinguisher with adjustable sound pressure

technical field

The invention relates to the technical field of fire fighting equipment, in particular to a fire extinguisher with adjustable sound pressure.

Background technique

The rapid development of human beings brings not only social progress, but also various hazards that affect the safety of human life and property. Fire is one of them. There are many kinds of traditional fire extinguishing methods, but the various fire extinguishing scenarios that firefighters have to face require far more fire extinguishing methods than the existing methods. For a series of special places such as electrical equipment places, special methods are required for fire extinguishing. For example, the use of gas fire extinguishing systems such as Halon series, carbon dioxide, etc. are often used in such places. However, the gas fire extinguishing system has some disadvantages: the misoperation of the gas fire extinguishing system in the confined space will threaten the life safety of the people inside, and the fire extinguishing start in an emergency requires the evacuation of personnel and affects the start time.

Contents of the invention

The technical problem to be solved by the present invention is to provide a fire extinguisher with adjustable sound pressure, which can adjust the sound pressure and improve the fire extinguishing effect.

The technical solution adopted by the present invention to solve the technical problems is: provide a fire extinguisher with adjustable sound pressure, including a power supply, a signal generator, a power amplifier and a loudspeaker, the power supply is used to provide power for the fire extinguisher; The device is used to generate a low-frequency square wave analog signal, and the purpose of changing the voltage is achieved by adjusting the signal frequency; the power amplifier is used to amplify the low-frequency square wave analog signal without distortion; the sounding end of the speaker is equipped with a sound chamber ; The loudspeaker converts the amplified low-frequency square wave analog signal into sound waves for playing; the sound cavity is used for directional gathering of the sound waves played by the loudspeaker.

An automatic monitoring fire warning module is also installed on the power supply; the automatic monitoring fire warning module automatically turns on the power supply when a fire occurs during monitoring.

The signal generator adjusts the frequency of generating the low frequency square wave analog signal through the finite element analysis method to achieve the best fire extinguishing state.

The power amplifier is provided with overvoltage, overcurrent and overheat protection modules.

The acoustic cavity adopts a parabolic retractable structure.

The frequency of the low frequency square wave analog signal generated by the signal generator is 65Hz.

Beneficial effect

Owing to adopting above-mentioned technical scheme, the present invention has following advantage and positive effect compared with prior art:

The invention adopts the finite element simulation analysis method to discretize the continuous solution area so that it becomes a combination composed of finite units, and establishes the finite element basic equation of the sound field to simulate the distribution of the sound field. The complex process is decomposed into simple processes, and the results with high reliability and accuracy are obtained.

The present invention achieves the purpose of adjusting the sound pressure by adjusting the f frequency. The greater the sound pressure, the greater the increment of the air pressure, and the worse the density of the air. When the flame position is in the time when the air is sparse, the concentration of oxygen, pressure, and gas combustibles are all reduced to achieve the effect of inhibiting combustion. Make the fire extinguishing speed of the fire extinguisher reach the best state.

The power source adopted in the present invention is a mobile power source, which also has an automatic monitoring fire warning module, and is equipped with manual and automatic switches at the same time, which is more convenient and safer.

The present invention can be applied to most kinds of fire sources.

The invention can introduce unmanned aerial vehicles to carry out automatic fire extinguishing, and people only need to carry out remote control.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a cuboid indoor space sound field distribution diagram;

Figure 3 is a cloud map of the sound pressure distribution at a frequency of 30 Hz;

Figure 4 is a cloud map of the sound pressure distribution at a frequency of 65Hz.

detailed description

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

The embodiment of the present invention relates to a fire extinguisher with adjustable sound pressure. As shown in FIG. The mobile power supply 1 supplies power to the fire extinguisher. The biggest difference with traditional fire extinguishers is that the mobile power supply 1 is equipped with an automatic monitoring fire warning module. When the automatic monitoring fire warning module detects a fire, it can automatically turn on the power supply. The automatic monitoring fire warning module is provided with a manual switch and an automatic switch. When the manual switch is turned on, the automatic monitoring fire warning module cannot automatically turn on the power supply. The signal generator 2 generates a low-frequency square wave analog signal, and the purpose of changing the voltage is achieved by adjusting the frequency of the signal. The power amplifier 3 is used to amplify the low-frequency square wave analog signal without distortion, and the power amplifier selected in the present invention has relatively perfect overvoltage, overcurrent and overheating protection functions. Speaker 4 converts the amplified square wave analog signal into sound waves. The sounding end of the loudspeaker 4 is connected with a sound chamber 5, and the sound chamber 5 directionally gathers the sound waves played by the loudspeaker 4 and increases the sound pressure. Through theoretical research and experimental analysis, it is concluded that the parabolic stretchable acoustic cavity structure can achieve the best fire extinguishing effect.

As shown in Figure 2, use ANSYS finite element analysis software to model, select the unit type as FLUID30 three-dimensional sound field unit, simulate the sound field distribution of a cuboid indoor space, and distinguish the indoor air from the air near the wall, and use different units modeling. First create key points, then create straight lines, create volumes, and then use the finite element method to divide the cuboid interior space into grids. Divide the cuboid with coupling elements, modify the indoor air element type to air elements, and then apply displacement constraints to the nodes on the wall. Set the walls and windows to two different acoustic impedances. Set a cylindrical sound source in a rectangular space, and adjust different frequencies for the sound source.

The ANSYS software is set to harmonic response analysis, and the sound pressure distribution cloud images of the real part and imaginary part of different frequencies in the space are respectively extracted. As shown in Figure 3 and Figure 4, according to the analysis of the comparison results, the low-frequency sound source at the frequency f=65Hz makes the maximum value of the sound pressure in this area is 19.907, the minimum value is -53.6514, and the farther away from the sound source , the smaller the sound pressure. Under the same temperature field, the lower the frequency, the more uniform the distribution of the sound field, and the longer the wavelength; while in the case of relatively high frequencies, the distribution of the sound field will change significantly, the farther away from the sound source, the shorter the wavelength, and the longer the wavelength. The pressure is relatively small. The sound pressure parameter value of the best fire extinguishing effect of the fire extinguisher is obtained through the above analysis, and then the signal generator can generate a low-frequency square wave signal of a corresponding frequency according to the analysis result.

Claims (6)

1. A fire extinguisher with adjustable sound pressure, comprising power supply (1), signal generator (2), power amplifier (3) and loudspeaker (4), it is characterized in that, described power supply (1) is used for fire extinguisher Provide power; the signal generator (2) is used to generate a low-frequency square wave analog signal, and by adjusting the frequency of the signal to achieve the purpose of changing the voltage; the power amplifier (3) is used to convert the low-frequency square wave analog signal Carry out undistorted amplification; The sounding end of described loudspeaker (4) is equipped with acoustic cavity (5); Described loudspeaker (4) converts the amplified low-frequency square wave analog signal into sound wave and plays; Described acoustic cavity (5) is used for The sound waves played by the loudspeaker (4) are directionally gathered. 2. The fire extinguisher with adjustable sound pressure according to claim 1, characterized in that, an automatic monitoring fire warning module is also installed on the power supply (1); , the power is turned on automatically (1). 3. The fire extinguisher with adjustable sound pressure according to claim 1, characterized in that, the signal generator (2) adjusts the frequency of generating the low-frequency square wave analog signal by finite element analysis to achieve the best fire extinguishing state . 4. The fire extinguisher with adjustable sound pressure according to claim 1, characterized in that the power amplifier (3) is provided with overvoltage, overcurrent and overheat protection modules. 5. The fire extinguisher with adjustable sound pressure according to claim 1, characterized in that, the sound chamber (5) adopts a parabolic retractable structure. 6. The fire extinguisher with adjustable sound pressure according to claim 1, characterized in that the frequency of the low-frequency square wave analog signal generated by the signal generator (2) is 65 Hz.