Mining broadcast signal transmission control system

Abstract

The utility model discloses a mining broadcast signal transmission control system, which comprises a main control module, an audio drive circuit, a high-frequency signal detection circuit, an audio filter circuit, a self-oscillation circuit and a power supply module, the main control module is connected with the input end of the audio drive circuit, and the output end of the audio drive circuit is connected with the input end of the audio filter circuit through a two-core cable; the input end of the self-oscillation circuit is connected with the input end of the audio filter circuit, and the output end of the self-oscillation circuit is connected with the main control module; the input end of the high-frequency signal detection circuit is connected with the input end of the audio filter circuit, and the output end of the high-frequency signal detection circuit is connected with the main control module; and the power supply module is used for supplying power to other modules in the mining broadcast signal transmission control system. The utility model provides a mining broadcast signal transmission control system, which can realize simultaneous transmission of audio signals and control signals, and solves the problems of difficult maintenance and low transmission efficiency.

Description

Technical Field

[0001] The utility model relates to a mine-used broadcast signal transmission control system. Background Art

[0002] At present, it is well known that miners have always been one of the high-risk occupations. The geological conditions of underground coal mines are complex, the working space is small, and the content of various harmful gases and environmental factors underground are in an uncontrollable state, which brings great difficulties to production scheduling and personnel safety. In order to strengthen the monitoring of underground mines and reduce and eliminate the occurrence of accidents, emergency broadcasting is increasingly widely used in various mines.

[0003] Emergency broadcasting has always been one of the commonly used equipment in mine production, mainly divided into analog broadcasting and digital broadcasting. Analog broadcasting uses two-core wires for audio and ground transmission, and the control signal is routed separately, which invisibly increases the cable cost. Digital broadcasting is divided into pure digital and digital IP broadcasting. Pure digital broadcasting uses two-core wires to transmit signals, but there is a distance problem. Once the distance exceeds a certain range, it will lead to poor sound quality and abnormal calls. Digital IP broadcasting mainly uses network transmission, and the transmission media are divided into network cables, optical fibers, and cables. All of them require the help of network equipment, which increases power consumption and hardware costs; emergency broadcasting long-distance signal transmission has always been an urgent problem that needs to be solved in emergency communications underground in coal mines. Therefore, the application of using two-core cables to transmit audio and control signal circuits is also urgently needed by coal mining companies. Summary of the invention

[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a mine broadcast signal transmission control system, which can realize the simultaneous transmission of audio signals and control signals and solve the problems of difficult maintenance and low transmission efficiency.

[0005] In order to solve the above technical problems, the technical solution of the utility model is:

[0006] A mine broadcast signal transmission control system, comprising a main control module, an audio drive circuit, a high-frequency signal detection circuit, an audio filter circuit, a self-excited oscillation circuit and a power supply module;

[0007] The main control module is connected to the input end of the audio driving circuit, and the output end of the audio driving circuit is connected to the input end of the audio filtering circuit through a two-core cable;

[0008] The input end of the self-excited oscillation circuit is connected to the input end of the audio filter circuit, and the output end of the self-excited oscillation circuit is connected to the main control module;

[0009] The input end of the high-frequency signal detection circuit is connected to the input end of the audio filter circuit, and the output end of the high-frequency signal detection circuit is connected to the main control module;

[0010] The power supply module is used to supply power to other modules in the mine broadcast signal transmission control system.

[0011] Furthermore, the power supply module includes a first step-down module, a second step-down module and a power isolation module, the output end of the first step-down module is connected to the input end of the second step-down module, the output end of the second step-down module is connected to the input end of the power isolation module, the output end of the second step-down module supplies power to the main control module, the high-frequency signal detection circuit, the self-excited oscillation circuit and the audio filter circuit, and the output end of the power isolation module supplies power to the audio drive circuit.

[0012] Furthermore, the first buck module includes a buck chip IC2, and the model of the buck chip IC2 is TPS5450.

[0013] Furthermore, the second buck module includes a buck chip IC1, and the model of the buck chip IC1 is LM1117-3.3.

[0014] Furthermore, the power isolation module includes an isolation chip IC6, and the model of the isolation chip IC6 is TPS76318.

[0015] Furthermore, the main control module includes an MCU chip IC5, and the model of the MCU chip IC5 is NXP LPC1778.

[0016] Furthermore, the audio driving circuit includes an audio codec chip IC8, and the model of the audio codec chip IC8 is VS1063.

[0017] By adopting the above technical solution, the utility model integrates high-frequency signal generation, detection and signal filtering functions, uses a two-core cable to realize the simultaneous transmission of audio signals and control signals, and ensures that the high-frequency signal detection circuit can clearly restore the audio signal to the main control module and execute control instructions, thereby realizing the control of the mining broadcasting system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a principle block diagram of a mine broadcast signal transmission control system of the utility model;

[0019] Figure 2 This is a circuit schematic diagram of the main control module of the utility model;

[0020] Figure 3 It is a circuit principle diagram of the audio driving circuit of the utility model;

[0021] Figure 4 This is a circuit schematic diagram of the high-frequency signal detection circuit of the utility model;

[0022] Figure 5 This is a circuit schematic diagram of the audio filter circuit of the utility model;

[0023] Figure 6 It is a circuit principle diagram of the self-excited oscillation circuit of the utility model;

[0024] Figure 7 This is a circuit schematic diagram of the power supply module of the utility model. DETAILED DESCRIPTION

[0025] In order to make the content of the utility model more clearly understood, the utility model is further described in detail below based on specific embodiments and in conjunction with the accompanying drawings.

[0026] like Figure 1 As shown, this embodiment provides a mine broadcast signal transmission control system, which includes a main control module, an audio drive circuit, a high-frequency signal detection circuit, an audio filter circuit, a self-excited oscillation circuit and a power supply module.

[0027] The main control module is connected to the input end of the audio driving circuit, and the output end of the audio driving circuit is connected to the input end of the audio filter circuit through a two-core cable. The input end of the self-excited oscillation circuit is connected to the input end of the audio filter circuit, and the output end of the self-excited oscillation circuit is connected to the main control module. The input end of the high-frequency signal detection circuit is connected to the input end of the audio filter circuit, and the output end of the high-frequency signal detection circuit is connected to the main control module. The power supply module is used to supply power to other modules in the mine broadcast signal transmission control system.

[0028] like Figure 7 As shown, the power supply module of this embodiment includes a first step-down module, a second step-down module and a power isolation module. The output end of the first step-down module is connected to the input end of the second step-down module, and the output end of the second step-down module is connected to the input end of the power isolation module. The output end of the second step-down module supplies power to the main control module, the high-frequency signal detection circuit, the self-excited oscillation circuit and the audio filter circuit, and the output end of the power isolation module supplies power to the audio drive circuit.

[0029] The system is powered by a DC18V power supply. The slow-start circuit uses the P-MOS tube T1 as a switch, and the resistors R3, R4, R10, and R15 are connected in parallel. By controlling the on and off of the transistor Q1, and then controlling the P-MOS tube, the slow-start function is enabled. The first step-down module includes a step-down chip IC2, the model of which is TPS5450, which reduces the voltage from 18V to 5V. The circuit output voltage = 1.221*(1+R14 / R19). The second step-down module includes a step-down chip IC1, the model of which is LM1117-3.3. After the power supply is stepped down to 5V, it is stepped down to 3.3V through the step-down chip IC1 to power the main control module, the high-frequency signal detection circuit, the self-excited oscillation circuit, and the audio filter circuit. The power isolation module includes an isolation chip IC6, the model of which is TPS76318. The 3.3V power supply is then output through the isolation chip IC6 to power the audio codec chip IC8.

[0030] like Figure 2 As shown, the main control module of this embodiment includes an MCU chip IC5, the model of the MCU chip IC5 is NXPLPC1778, equipped with enough IO interfaces, and the function expansion is easier to achieve. With a large-capacity storage chip, data can be better collected for backup.

[0031] like Figure 3 As shown, the audio driving circuit of this embodiment is used to output audio signals, and the main control module communicates with the audio driving circuit through the SPI interface. The audio driving circuit includes an audio codec chip IC8, and the model of the audio codec chip IC8 is VS1063. The analog microphone MIC is connected to the audio codec chip IC8, and the audio codec chip IC8 communicates with the microprocessor IC5 through pins 23, 28, 29, and 30, and sends instructions to the audio codec chip IC8 through the MCU chip IC5 to perform audio encoding and decoding to output MP3 audio.

[0032] like Figure 4As shown, the high-frequency signal detection circuit of this embodiment is used to detect the fixed high-frequency signal generated by the self-excited oscillation circuit, and convert the high-frequency signal into a voltage signal and transmit it to the MCU chip IC5 of the main control module. The MCU chip IC5 performs AD detection through the IO port, collects the signal and converts it into an instruction, performs key dialing, and notifies the host computer client to broadcast. The high-frequency signal detection circuit includes operational amplifiers IC4 and IC6 of model MS8052 / M, and adopts a 2-stage 4th-order bandpass filter circuit. The bandpass filter only allows specific frequencies to pass, and effectively suppresses the signals of other frequencies. For the design of low-pass filter, the capacitor is selected as 100pF. For the design of high-pass filter, the capacitor is selected as 100pF. Then the resistance value combined with the capacitor is calculated according to the formula R=1 / 2πfc, that is, R29, R30, R31 and R32 in this figure are obtained. In order to eliminate the error caused by the offset current of the op amp, the DC resistance of the op amp's in-phase input and reverse input to the ground is basically equal. The circuit connects the detected signal to the IO of the main control circuit through the KG port, and the main control circuit processes the signal and uploads it.

[0033] like Figure 5 As shown, the audio filter circuit of this embodiment is used for audio filtering. The audio filter circuit removes high-frequency and low-frequency signals (only retains audio signals from 20Hz to 20KHz), outputs signals to the power amplifier circuit, and the power amplifier circuit outputs signals to the speaker for broadcasting. The audio filter circuit includes an operational amplifier IC4 of model MS8052 / M. The circuit adopts a 1st-level 4th-order low-pass filter circuit. The capacitors are selected as 220pF and 3.3nF. Then, the cut-off frequency is calculated according to the formula f=1 / 2πRC, and the audio signal in the range of 20Hz to 20KHz is output to the power amplifier speaker.

[0034] like Figure 6 As shown, the self-excited oscillation circuit of this embodiment is used to send a fixed frequency to the MCU chip IC5 of the main control module for detecting the level signal. The MCU chip IC5 adopts AD detection, detects the signal and converts it into an instruction, performs key dialing, and notifies the host computer client to make a call; it can also detect 30KHZ-40KHZ high-frequency signals. The main MCU chip IC5 adopts AD detection, detects the signal and converts it into status information, such as online status. The self-excited oscillation circuit includes an operational amplifier IC3 of model MS8052 / M. The circuit adopts a dual-pass operational amplifier, one part of which is used as a voltage follower for voltage stabilization, and the resistors are selected as 12K and 10K for voltage division. The field effect tube IRLML2803TRPBF is used as a switch to control the gate signal, that is, to control different frequency outputs to generate an oscillation signal, and the oscillation signal is transmitted to the high-frequency signal detection circuit through the resistor R11.

[0035] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A mine broadcast signal transmission control system, characterized in that: It includes a main control module, an audio driving circuit, a high-frequency signal detection circuit, an audio filtering circuit, a self-excited oscillation circuit and a power supply module; The main control module is connected to the input end of the audio driving circuit, and the output end of the audio driving circuit is connected to the input end of the audio filtering circuit through a two-core cable; The input end of the self-excited oscillation circuit is connected to the input end of the audio filter circuit, and the output end of the self-excited oscillation circuit is connected to the main control module; The input end of the high-frequency signal detection circuit is connected to the input end of the audio filter circuit, and the output end of the high-frequency signal detection circuit is connected to the main control module; The power supply module is used to supply power to the main control module, the high-frequency signal detection circuit, the self-excited oscillation circuit, the audio filter circuit and the audio drive circuit.

2. The mine broadcast signal transmission control system according to claim 1 is characterized in that: The power supply module includes a first step-down module, a second step-down module and a power isolation module. The output end of the first step-down module is connected to the input end of the second step-down module, the output end of the second step-down module is connected to the input end of the power isolation module, the output end of the second step-down module supplies power to the main control module, the high-frequency signal detection circuit, the self-excited oscillation circuit and the audio filter circuit, and the output end of the power isolation module supplies power to the audio drive circuit.

3. The mine broadcast signal transmission control system according to claim 2 is characterized in that: The first buck module includes a buck chip IC2, and the model of the buck chip IC2 is TPS5450.

4. The mine broadcast signal transmission control system according to claim 2 is characterized in that: The second buck module includes a buck chip IC1, and the model of the buck chip IC1 is LM1117-3.

3.

5. The mine broadcast signal transmission control system according to claim 2 is characterized in that: The power isolation module includes an isolation chip IC6, and the model of the isolation chip IC6 is TPS76318.

6. The mine broadcast signal transmission control system according to claim 1, characterized in that: The main control module includes an MCU chip IC5, and the model of the MCU chip IC5 is NXP LPC1778.

7. The mine broadcast signal transmission control system according to claim 1 is characterized in that: The audio driving circuit includes an audio codec chip IC8, and the model of the audio codec chip IC8 is VS1063.

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