A high-precision pointer display digital pressure gauge

Abstract

The present invention relates to a high-precision pointer display digital pressure gauge, comprising: a mechanical part and a digital part. The mechanical part includes: a pointer and a bourdon tube, and the pointer and the bourdon tube are linked through a movement. The digital part includes: a power supply, a sensor, a comparator amplifier, a CPU, and a reference voltage circuit. The pressure sensor inside the bourdon tube amplifies the collected signal by the comparator amplifier, compensates the signal, and converts the analog signal into a digital signal through analog-to-digital conversion. The converted digital signal enters the CPU for signal processing, and the processed digital signal is output as an analog signal through digital-to-analog conversion. The reference voltage circuit performs multi-stage voltage division on the received analog signal through a voltage division circuit and drives the bourdon tube through the voltage after voltage division to control the pointer to display the pressure value. This patent can achieve high precision and real-time display through the digital pressure gauge, and at the same time, it can also be intuitively displayed through the pointer, combining the advantages of digital display and pointer display.

Description

Technical Field

[0001] The present invention discloses a digital pressure gauge, belonging to the technical field of instrument measurement, and relates to a high-precision pointer-display digital pressure gauge. Background Art

[0002] The digital pressure gauge has a large sensitivity coefficient. The digital pressure gauge is a new type of intelligent and multifunctional measuring instrument integrating sensing technology, electronic technology and microcomputer technology. It can not only meet the pressure measurement in industrial sites, but also be used as a standard meter in laboratories. The digital pressure gauge can be divided into an integral type and a separated type according to its structure. Most of those used in the field are of the integral type, that is, sensing, conversion and display are integrated. The digital pressure gauge is widely used in the fields of hydropower, tap water, petroleum, chemical industry, machinery and hydraulics, and is used for real-time monitoring, measurement and display of digital pressure gauges for fluid media. Summary of the Invention

[0003] The object of the present invention is to provide a high-precision pointer-display digital pressure gauge, which can scientifically measure, control and be convenient to use. Through digital signal processing, the pointer control module outputs a divided voltage to drive the deformation of the bourdon tube, indirectly driving the pointer to indicate the pressure value. To achieve the above object, the following technical solutions are adopted: It includes: a mechanical part and a digital part. The mechanical part includes: a pointer and a bourdon tube. The pointer and the bourdon tube are linked through a pointer control module including a movement and a connecting rod. The digital part includes: a power supply, a sensor, a comparison amplifier, a CPU, and a reference voltage circuit. The power supply is used to supply power to the pointer control module, the sensor, the comparison amplifier, and the CPU. The sensor is attached to the inner side wall of the bourdon tube. The input end of the comparison amplifier is connected to the output end of the reference voltage circuit and the output end of the sensor. Through the comparison amplifier, the comparison, amplification and temperature compensation of the electrical signal output by the sensor are realized. The output end of the comparison amplifier is connected to an analog-to-digital converter to realize the conversion of the analog signal into a digital signal. The output end of the analog-to-digital converter is connected to the CPU. The output end of the CPU is connected to a digital-to-analog converter to convert the digital signal output by the CPU into an analog signal. The output end of the digital-to-analog converter is connected to the reference voltage circuit. The output end of the reference voltage circuit is connected to a voltage dividing circuit. The voltage dividing circuit is used to divide the reference voltage into different levels of voltage. The voltage dividing circuit is used to drive the deformation of the bourdon tube, thereby controlling the pointer to turn to the corresponding pressure value.

[0004] Preferably, the sensor adopts a pressure sensor, which is used to collect the pressure signal of the medium entering the pressure gauge. The sensor is attached to the inner side wall of the bourdon tube along the axial direction of the bourdon tube.

[0005] Preferably, the positive end of the comparison amplifier is connected to the output end of the sensor, and the negative end is connected to the reference voltage circuit, which is used to amplify the collected pressure signal.

[0006] Preferably, the power supply is battery-powered, eliminating the need for an external power supply. It has functions of overcharge protection and automatic shutdown under low voltage for the battery voltage, ensuring that the battery is not damaged due to charging or under-voltage, and having a long battery life. The power supply is also connected to a digital-to-analog converter, an analog-to-digital converter, and a reference voltage circuit to provide the working voltage for them.

[0007] Preferably, the reference voltage circuit is also connected to the digital-to-analog converter and the analog-to-digital converter to provide a DC reference voltage.

[0008] Preferably, the voltage division circuit includes: resistor R1 and resistor R2. One end of resistor R1 is connected to the power supply, and the other end is connected to the output end of the reference voltage circuit and resistor R2 in series. The other end of resistor R2 is grounded.

[0009] Beneficial effects:

[0010] Combining a digital pressure gauge and a pointer pressure gauge, the pressure sensor inside the bourdon tube amplifies the collected pressure signal of the medium by a comparison amplifier, compensates the signal, and converts the analog signal into a digital signal through analog-to-digital conversion. The converted digital signal enters the CPU for signal processing, and the processed digital signal is converted back into an analog signal through digital-to-analog conversion for output. The reference voltage circuit divides the received analog signal through a voltage division circuit for multi-stage voltage division output, and then drives the bourdon tube with the divided voltage to control the pointer to display the pressure value. This patent can achieve high precision and real-time display through the digital pressure gauge, and at the same time, it can visually display through the pointer, combining the advantages of digital display and pointer display. Description of the Drawings

[0011] Figure 1 It is a schematic diagram of the system device structure;

[0012] Figure 2 It is a schematic diagram of the structure of the pointer pressure gauge;

[0013] Figure 3 It is a schematic diagram of the structure of the voltage division circuit driving the deformation of the bourdon tube;

[0014] In the figure, 1. Connector; 2. Dial; 3. Pointer; 4. Bourdon tube; 5. Movement; 6. Link; 7. Electromagnet. Detailed Embodiments

[0015] The following further describes the detailed embodiments of the present invention with reference to the drawings.

[0016] The connection of the functional units of the high-precision compass display digital pressure gauge is as Figure 1 shown, including: a mechanical part and a digital part, Figure 2As shown in the figure, the mechanical part includes: a pointer and a bourdon tube. The pointer and the bourdon tube are linked through a pointer control module including a movement and a connecting rod. The pressure gauge introduces the medium through a joint. The bourdon tube undergoes elastic deformation, drives the movement through the connecting rod, and the rotation of the movement drives the pointer to rotate on the dial.

[0017] The digital part includes: a power supply, a sensor, a comparator amplifier (OPA), a CPU, and a reference voltage circuit. The CPU has functions such as automatic zero clearing when powered off and voltage range switching. The power supply is used to supply power to the pointer control module, the sensor, the comparator amplifier, and the CPU. The sensor is attached to the inner wall of the bourdon tube and is a pressure sensor. The pressure sensor is attached along the axis of the inner wall of the bourdon tube. The pressure sensor exhibits high-frequency sampling characteristics and is used to collect the pressure signal generated by the medium. The input end of the comparator amplifier is connected to the output end of the reference voltage circuit and the output end of the sensor through wires, that is, the positive end is connected to the output end of the sensor, and the negative end is connected to the reference voltage circuit. The signal comparison amplification and temperature compensation are realized through the comparator amplifier to achieve high-precision output. The output end of the comparator amplifier is connected to an analog-to-digital converter to realize the conversion of analog signals to digital signals. The output end of the analog-to-digital converter (ADC) is connected to the CPU, and the digital circuit after the analog signal conversion is input to the CPU for processing. The CPU automatically compensates for the zero drift, temperature drift, nonlinearity, etc. of the instrument to ensure high precision within the usage conditions of the instrument. The output end of the CPU is connected to a digital-to-analog converter to convert the digital signal output by the CPU into an analog signal. The output end of the digital-to-analog converter (DAC) is connected to the reference voltage circuit, and the output end of the reference voltage circuit is connected to a voltage dividing circuit. The voltage dividing circuit divides the reference voltage into different levels of voltage V, and the output voltage V of the voltage dividing circuit is used to drive the deformation of the bourdon tube, thereby controlling the pointer to turn to the corresponding pressure value.

[0018] Figure 1 、 Figure 3 As shown in [figure number], the voltage dividing circuit is composed of resistor R1 and resistor R2. One end of resistor R1 is connected to the power supply, the other end is connected to the output end of the reference voltage circuit and the series resistor R2, and the other end of resistor R2 is grounded. The current is output to the coil of the electromagnet. One side of the bourdon tube close to the coil is made of iron. When the coil is energized, the bourdon tube deforms, and the greater the current, the greater the deformation. The deformation of the bourdon tube drives the change of the pointer through the connecting rod and the movement. With this structure, the DC input has good stability. To ensure accuracy, the electromagnet is located at the fixed end of the bourdon tube. At the same time, two symmetrical electromagnets can also be made and located on both sides of the fixed end of the bourdon tube to prevent one end of the bourdon tube from being offset due to force.

[0019] The power supply is powered by a battery, does not require an external power supply, and has functions of overcharge and under-voltage automatic shutdown protection for the battery voltage, ensuring that the battery is not damaged due to charging or under-voltage, and has a long service life. The power supply is also connected to the digital-to-analog converter, the analog-to-digital converter, and the reference voltage circuit.

[0020] The above high-precision compass display digital pressure gauge can achieve high precision through the digital pressure gauge, display in real time, realize functions such as one-key switching of various voltage units and power-off reset, and at the same time can be intuitively displayed through the pointer, combining the advantages of digital display and pointer display.

[0021] Finally, it should be noted that the above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced without departing from the spirit and scope of the present invention, and the appended claims are intended to cover such modifications or equivalent replacements that fall within the spirit and scope of the present invention.

Claims

1. A high-precision pointer display digital pressure gauge, comprising: The mechanical part and the digital part. The mechanical part includes: a pointer and a bourdon tube. The pointer and the bourdon tube are linked by a movement. The digital part includes: a power supply, a sensor, a comparison amplifier, a CPU, and a reference voltage circuit. The power supply is used to supply power to the sensor, the comparison amplifier, and the CPU. It is characterized in that: the sensor is attached to the inner side of the bourdon tube, the input end of the comparison amplifier is connected to the output end of the reference voltage circuit and the output end of the sensor, the output end of the comparison amplifier is connected to an analog-to-digital converter, the output end of the analog-to-digital converter is connected to the CPU, the output end of the CPU is connected to a digital-to-analog converter, the output end of the digital-to-analog converter is connected to the reference voltage circuit, and the output end of the reference voltage circuit is connected to a voltage dividing circuit. The voltage dividing circuit is used to drive the deformation of the bourdon tube; The sensor uses a pressure sensor, and the sensor is attached to the inner side wall of the bourdon tube along the axial direction of the bourdon tube; The voltage dividing circuit includes: resistor R1 and resistor R2. One end of resistor R1 is connected to the power supply, the other end is connected to the output end of the reference voltage circuit and is in series with resistor R2. The other end of resistor R2 is grounded, and the current is output to the coil of the electromagnet. One side of the bourdon tube close to the coil is made of iron. When the coil is energized, the bourdon tube deforms. The greater the current, the greater the deformation. The deformation of the bourdon tube drives the change of the pointer through a connecting rod and a movement.

2. The high-precision pointer display digital pressure gauge according to claim 1, wherein: The positive terminal of the comparison amplifier is connected to the output end of the sensor, and the negative terminal is connected to the reference voltage circuit, which is used to amplify the collected signal.

3. The high-precision pointer display digital pressure gauge according to claim 1, wherein: The power supply uses battery power supply, and the power supply is also connected to the digital-to-analog converter, the analog-to-digital converter, and the reference voltage circuit.

4. The high-precision pointer display digital pressure gauge according to claim 3, wherein: The reference voltage circuit is also connected to the digital-to-analog converter and the analog-to-digital converter, and is used to provide a DC reference voltage.

Images