Ultrasonic liquid level meter

Abstract

The utility model provides an ultrasonic liquid level meter which is based on an ultrasonic technology and is used for liquid level measurement in related scenes such as ponds and rivers. The utility model relates to a liquid level sensor, which comprises an upper shell, a lower shell, an ultrasonic transducer, a main control circuit board, a power supply circuit, a liquid level acquisition and processing circuit, an inclination angle detection circuit, a temperature acquisition circuit, a liquid crystal display circuit and an RS485 communication circuit, and the liquid level heights of related scenes such as ponds, dams and canals can be collected.

Description

Technical Field

[0001] The utility model relates to the field of ultrasonic measurement, and specifically to an ultrasonic level gauge based on ultrasonic technology for liquid level measurement in related scenarios such as ponds and rivers. Background Art

[0002] In recent years, seasonal floods, urban waterlogging and other situations have become increasingly serious, and each occurrence has brought huge losses to the economy and lives. High-efficiency and accurate liquid level measurement has become particularly important. When floods, waterlogging and other disasters occur, timely and accurate collection can be linked to a telemetry terminal to report data to the natural disaster emergency management platform for timely disposal. With the development of various emerging technologies, smart agriculture, forestry, animal husbandry and fishery have become popular, and liquid level measurement in scenarios such as paddy fields, irrigation canals, and fish ponds has also become an important technical indicator. Summary of the Invention

[0003] The utility model provides an ultrasonic level gauge, which adopts ultrasonic measurement technology for liquid level measurement in related scenarios such as ponds and rivers. Through frequency domain and generalized autocorrelation analysis, the utility model forms a software algorithm with accurate ranging, high stability and thorough noise filtering, and the measurement data is accurate and reliable.

[0004] In order to achieve the above object, the technical solution of the utility model is described as follows:

[0005] The ultrasonic level gauge includes an upper housing, a lower housing, an ultrasonic transducer, a main control circuit board, a power supply circuit, a liquid level acquisition and processing circuit, an inclination detection circuit, a temperature acquisition circuit, a liquid crystal display circuit, and an RS485 communication circuit. Its characteristics are:

[0006] The upper housing shields the main control circuit board and the liquid crystal device from rain and sun;

[0007] The lower housing installs the ultrasonic transducer and the main control circuit board;

[0008] The main control circuit board is placed inside the lower housing, placed in a transparent potting box, and fixedly connected to the lower housing with screws;

[0009] The power supply circuit is powered by an external device, and is internally regulated and stepped down as needed, and is connected through the waterproof outlet terminal of the lower housing;

[0010] The liquid level acquisition and processing circuit filters, couples and amplifies the echo signal to acquire a stable and reliable echo signal;

[0011] The inclination detection circuit corrects the measurement result through the trigonometric function relationship by collecting the installation inclination of the device through an acceleration sensor;

[0012] The temperature acquisition circuit collects the ambient temperature change through a temperature sensor and is used to correct the ultrasonic propagation speed at different temperatures;

[0013] The liquid crystal display circuit performs local liquid crystal display through an OLED;

[0014] The RS485 communication circuit is connected to an external device through a waterproof terminal to read and set data, and obtains the liquid level situation to perform inter-system linkage control;

[0015] Advantages of the present utility model:

[0016] (1) For the ultrasonic level gauge of the present utility model, the recognition of small echo signals in the hardware circuit is more stable and the filtering of noise is more thorough.

[0017] (2) For the ultrasonic level gauge of the present utility model, a software algorithm with accurate ranging, high stability, and thorough noise filtering is formed through frequency domain and generalized autocorrelation analysis, and the measurement data is accurate and reliable. Description of the drawings

[0018] Att Figure 1 is the circuit block diagram of the ultrasonic level gauge of the present utility model. Detailed implementation manners

[0019] The technical solution of the present utility model will be further described in detail below in combination with the detailed implementation manners and the description of the drawings.

[0020] As shown in Att Figure 1 : The ultrasonic level gauge includes an upper housing, a lower housing, an ultrasonic transducer, a main control circuit board, a power supply circuit, a liquid level acquisition and processing circuit, an inclination detection circuit, a temperature acquisition circuit, a liquid crystal display circuit, and an RS485 communication circuit.

[0021] The power supply circuit is powered by an external device, and performs voltage stabilization and step-down processing internally as needed, and is connected through the waterproof outlet terminal of the lower housing; specifically, the power supply circuit is powered by 9 - 24V DC or AC, is stepped down to 8V through a voltage regulator chip L7808, and then is stepped down to 3.3V through a voltage regulator chip CE630LA339 to provide working power for each functional module.

[0022] The liquid level acquisition and processing circuit collects a stable and reliable echo signal through filtering, coupling and amplification processing of the echo signal; specifically, the liquid level acquisition and processing circuit performs a series of hardware processing such as coupling, hardware filtering, and small signal amplification on the echo signal of the ultrasonic transducer to obtain an identifiable signal, which is input into the microprocessor for digital analysis and processing.

[0023] The inclination angle detection circuit corrects the trigonometric function relationship of the measurement result by collecting the installation inclination angle of the device through an acceleration sensor. Specifically, the three-axis acceleration sensor and the microprocessor obtain the angle between the device and the horizontal direction through IIC communication.

[0024] The temperature acquisition circuit collects the ambient temperature change through a temperature sensor for correcting the ultrasonic propagation speed at different temperatures. Specifically, the temperature acquisition circuit uses a high-precision NTC resistor. By utilizing its temperature-sensitive characteristic, the microprocessor collects the NTC resistor value and calculates the temperature in combination with the NTC temperature data table.

[0025] The liquid crystal display circuit performs local liquid crystal display through an OLED. Specifically, the liquid crystal display circuit conducts data interaction with the microprocessor through IIC communication and sends the display data information as required.

[0026] The RS485 communication circuit is connected to an external device through a waterproof terminal to read and set data, and performs inter-system linkage control by obtaining the liquid level situation; the RS485 communication circuit and the microprocessor use serial communication. Specifically, the RS485 communication chip uses SN65HVD3082EDR, one path is optically isolated and the other path is non-isolated, which is a classic application of the RS485 communication circuit and will not be elaborated here.

Claims

1. Ultrasonic liquid level meter, including upper shell, lower shell, ultrasonic transducer, main control circuit board, power supply circuit, liquid level acquisition and processing circuit, inclination detection circuit, temperature acquisition circuit, liquid crystal display circuit, RS485 communication circuit, its characteristics are: The upper housing is used to shield the main control circuit board and the liquid crystal device from rain and sunlight; The lower housing is provided with an ultrasonic transducer and a main control circuit board; The main control circuit board is placed inside the lower housing, placed in a transparent glue potting box, and fixedly connected to the lower housing with screws; The power supply circuit is powered by an external device, and the internal voltage is stabilized and reduced as needed, and connected through the waterproof outlet terminal of the lower shell; The liquid level acquisition and processing circuit collects a stable and reliable echo signal by filtering, coupling and amplifying the echo signal; The inclination detection circuit performs trigonometric function correction on the measurement result by collecting the installation inclination of the device through the acceleration sensor; The temperature acquisition circuit acquires the change of the ambient temperature through the temperature sensor, and is used to correct the ultrasonic wave propagation speed at different temperatures; The liquid crystal display circuit performs local liquid crystal display via OLED; The RS485 communication circuit is connected to an external device through a waterproof terminal output line to read data, and the linkage control between systems is performed by obtaining the liquid level situation.

Images