Intrinsic safety type open channel flow sensor

Abstract

According to the intrinsic safety type open channel flow sensor, the underwater acoustic transducers and the pressure transmitter are adopted for working, flow and flow velocity are obtained through the transducers, one ultrasonic transducer is responsible for sending ultrasonic signals, the other ultrasonic transducer is used for receiving the ultrasonic signals, and the flow velocity and flow are calculated after the signals are processed. Water pressure and temperature are detected through the pressure transmitter, and a signal isolation module is arranged between the pressure transmitter and the main chip and is used for isolating signals and preventing high voltage and large current from damaging the main chip. Signals processed through a series of processes can be transmitted to a general monitoring station, and therefore the functions of monitoring the flow condition and the like are achieved. Current-limiting and voltage-limiting circuits or isolation modules are arranged on the input part and the output part of the whole ultrasonic flowmeter, so that energy in a system is effectively limited, the ultrasonic flowmeter can normally operate in a mine with a severe environment, and electric sparks cannot be generated to detonate inflammables.

Description

Technical Field

[0001] The utility model relates to an open channel flow sensor, in particular to an intrinsically safe open channel flow sensor for monitoring. Background Art

[0002] The intrinsically safe open channel flow sensor utilizes the Doppler effect of sound waves propagating in a fluid. By measuring the Doppler frequency shift of sound waves scattered by moving particles in the fluid, the velocity of the fluid is obtained. Underground open channels are one of the important ways to drain water from mines. Monitoring the open channel water flow with an intrinsically safe open channel flow sensor can reflect the total amount of water seepage underground. By analyzing the change in open channel water flow within a fixed time, a certain degree of early warning of mine water hazards can be provided, reducing the probability of mine water hazard accidents.

[0003] Existing open channel flow sensors using the Doppler effect do not use current and pressure limiting protection, and their internal energy is too large and prone to combustion. Summary of the Invention

[0004] In order to solve the above technical problems, the utility model is an intrinsically safe open channel flow sensor, and its technical solution is as follows:

[0005] The pressure transmitter comprises a housing and a base plate, the housing and the base plate being detachably connected, a cable protective cover being detachably mounted on the rear of the housing, a pressure transmitter and a circuit board being contained within the housing, the pressure transmitter being mounted on a pressure transmitter mounting block, the pressure transmitter mounting block being detachably mounted within a mounting groove at the front end of the base plate; an air duct of the pressure transmitter being connected to an air duct within a cable within a cable protective cover mounted at the rear of the housing, and power and signal lines on the pressure transmitter being connected to the circuit board;

[0006] Two underwater acoustic transducers are provided at the front end of the shell, and the ultrasonic signals of the two underwater acoustic transducers are connected. Each underwater acoustic transducer is connected to the main chip signal on the main board. The main board is also provided with a signal isolation module and a power supply isolation module. The external power supply is electrically connected to the circuit board through the power supply isolation module; the pressure transmitter is connected to the main chip signal of the circuit board through the signal isolation module; the main chip of the circuit board sends the signal to the general monitoring station through the signal isolation module.

[0007] Furthermore, corresponding mounting holes are provided between the shell and the base plate, and they are connected and fixed by matching bolts. A sealed cabin is formed inside and filled with insulating glue.

[0008] Furthermore, the shell and the bottom plate are both made of ABS flame retardant material.

[0009] The beneficial effects of the present invention are as follows: the present invention is an intrinsically safe open channel flow sensor, which uses a hydroacoustic transducer and a pressure transmitter to work. The flow rate is obtained through the transducer, one of the ultrasonic transducers is responsible for sending ultrasonic signals, and the other transducer is used to receive ultrasonic signals. The flow rate is calculated after the signal is processed. The water pressure and temperature are detected by the pressure transmitter. There is a signal isolation module between the pressure transmitter and the main chip, which is used to isolate the signal to prevent high voltage and high current from damaging the main chip. After the above series of processes, the signal will be transmitted to the general monitoring station, thereby realizing functions such as monitoring of the flow situation. The input and output parts of the entire ultrasonic flowmeter are made of current limiting and voltage limiting circuits or isolation modules, which effectively limit the energy inside the system, so that it can operate normally in mines with harsh environments and will not generate electric sparks to ignite flammable materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the structure of the utility model;

[0011] Figure 2 This is the structural diagram of the utility model;

[0012] As shown in the figure, 1. underwater acoustic transducer 2. pressure transmitter 3. pressure transmitter mounting block 4. circuit board 5. base plate 6. housing 7. cable protective cover. DETAILED DESCRIPTION

[0013] As shown in the figure, the present invention is an intrinsically safe open channel flow sensor comprising a housing 6 and a base plate 5. The housing 6 and base plate 5 are each provided with corresponding mounting holes at their four corners and are secured by matching bolts. A cable protection sleeve 7 is provided at the rear of the housing and is threadedly secured to the housing 6. The housing contains a pressure transmitter 2 and a circuit board 4. The pressure transmitter 2 is mounted on a pressure transmitter mounting block 3, which is removably mounted in a mounting slot at the front end of the base plate 5. The pressure transmitter's air duct is connected to the air duct within the cable within the cable protection sleeve installed at the rear of the housing. The power supply and signal lines of the pressure transmitter are connected to the circuit board.

[0014] Two underwater acoustic transducers 1 (DYW-LS-03A) are provided at the front end of the shell. The main chip on the circuit board (STM32L431RCT6) sends a signal to one of the underwater acoustic transducers 1, and then the underwater acoustic transducer 1 sends an ultrasonic wave to the water surface, and then the ultrasonic wave bounces back to the other underwater acoustic transducer. The underwater acoustic transducer that receives the signal then transmits the signal back to the main chip on the circuit board 4.

[0015] The pressure transmitter 2 (PT12) installed in the pressure transmitter mounting block 3 generates a pressure signal after sensing the pressure. The pressure signal is processed by the signal isolation module (signal isolation module, model ADUM1250ARZ-RL7) on the circuit board and then transmitted to the main chip (model STM32L431RCT6).

[0016] The external power supply line is processed by the power supply isolation on the circuit board (power supply isolation module, model LM2674N-ADJ) to power the circuit board. Then, the signal line in the same line as the external power supply transmits the signals from the underwater acoustic transducer and the pressure transmitter through the signal isolation on the circuit board to the universal monitoring station (KJ2461-F) that is matched with the sensor.

[0017] Installation process of this utility model:

[0018] Install the underwater acoustic transducer 1 into the mounting groove on the housing 6, and then connect the connecting wire of the underwater acoustic transducer to the circuit board 4. Install the pressure transmitter 2 inside the pressure transmitter mounting block 3, and then install the pressure transmitter mounting block into the mounting groove on the base plate 5 and tighten it with screws. Connect the air duct of the pressure transmitter to the air duct inside the cable in the cable protective cover 7 installed at the rear of the housing, and then connect the power supply line and signal line on the pressure transmitter to the circuit board 4. Connect the signal line and power supply line in the cable introduced at the rear of the housing to the circuit board to power the underwater acoustic transducer and pressure transmitter and transmit signals. After the housing and base plate are installed, a sealed cabin is formed inside, filled with insulating glue, and placed in the open channel of the mine.

[0019] The utility model works through transducers and pressure transmitters. The flow rate and velocity are obtained through the transducers, where one ultrasonic transducer is responsible for sending ultrasonic signals, and the other transducer is used to receive ultrasonic signals. The flow rate and velocity are calculated after the signals are processed. The water pressure and temperature are detected by the pressure transmitter, and there is a signal isolation module between the pressure transmitter and the main chip. Its function is to isolate the signal to prevent high voltage and high current from damaging the main chip. The signal processed through the above series of processes will be transmitted to the general monitoring station, thereby realizing functions such as monitoring of flow conditions. The input and output parts of the entire ultrasonic flowmeter are made of current limiting and voltage limiting circuits or isolation modules, which effectively limit the energy inside the system, so that it can operate normally in mines with harsh environments and will not generate electric sparks to ignite flammable materials.

[0020] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An intrinsically safe open channel flow sensor, comprising a housing (6) and a base plate (5), wherein the housing (6) and the base plate (5) are detachably connected, and a cable protection cover (7) is detachably mounted on the rear of the housing (6), characterized in that: The housing (6) contains a pressure transmitter (2) and a circuit board (4). The pressure transmitter (2) is mounted on a pressure transmitter mounting block (3). The pressure transmitter mounting block (3) is detachably mounted in a mounting groove at the front end of the base plate (5). The air duct of the pressure transmitter is connected to the air duct in the cable in the cable protection sleeve (7) installed at the rear of the housing. The power supply line and the signal line on the pressure transmitter are connected to the circuit board (4). Two underwater acoustic transducers are provided at the front end of the housing (6), the two underwater acoustic transducers are connected by ultrasonic signals, and each underwater acoustic transducer is connected to a main chip signal on the mainboard.

2. The intrinsically safe open channel flow sensor according to claim 1, characterized in that: The main board is also equipped with a signal isolation module and a power supply isolation module. The external power supply is electrically connected to the circuit board through the power supply isolation module; the pressure transmitter is connected to the circuit board main chip signal through the signal isolation module; the circuit board main chip sends the signal to the general monitoring station through the signal isolation module.

3. The intrinsically safe open channel flow sensor according to claim 1, characterized in that: Corresponding mounting holes are provided between the shell (6) and the bottom plate (5), which are connected and fixed by matching bolts, and a sealed cabin is formed inside and filled with insulating glue.

4. The intrinsically safe open channel flow sensor according to claim 1, wherein: The shell and base are made of ABS flame retardant material.

Images