Electronic barometer and barometric pressure measuring method

Abstract

The invention discloses an electronic barometer and an air pressure measurement method, and relates to the technical field of air pressure measurement, the electronic barometer comprises a barometer disc and a barometer base, the barometer disc comprises a circuit board, a pointer electrode and a bourdon tube, the circuit board is provided with an MCU microprocessor, a signal detection circuit and a plurality of PCB scale electrodes which are uniformly distributed at intervals in an arc shape, and the PCB scale electrodes are arranged on the circuit board. The signal detection circuit and the PCB scale electrodes are electrically connected with input and output ports (also called I / O ports) of the MCU microprocessor respectively, and the pointer electrode is electrically connected with the signal input end of the signal detection circuit through a Bourdon tube and a metal shell of the electronic barometer. The pointer electrode is fixed on the bourdon tube or linked with the bourdon tube; the pointer electrode and the bourdon tube are both made of conductive metal materials. The multifunctional electronic barometer provided by the invention is simple in structure and low in cost, and is very excellent in cost performance in the field of MPa-level high-pressure application.

Description

Technical Field

[0001] The invention relates to the technical field of air pressure measurement, in particular to an electronic air pressure gauge and an air pressure measurement method. Background Art

[0002] Commonly used barometers on the market are mainly classified into pointer barometers and electronic barometers. Pointer barometers are low-priced but simple in function, and their application in the intelligent field is limited. Existing electronic barometers can expand many functions, but they are large in size and expensive. Especially for MPa (megapascal) high-pressure barometers, the key component of existing electronic barometers is semiconductor pressure sensors, which are very expensive. Semiconductor pressure sensors that can measure 30MPa (megapascal) start at more than 60 yuan, and the cost of the whole machine is more than 150 yuan.

[0003] like Figure 1 The spring-shaped Bourdon tube pointer barometer 1 (axial pointer barometer) shown has the following working principle: the shape change caused by the change of gas pressure inside the Bourdon tube (also called spring tube) is converted into the deflection of the first pointer 12, which is displayed on the first scale plate 11. The spring-shaped Bourdon tube 13 at the center of the gauge head is hollow, and the tube head at the center of the spring-shaped Bourdon tube 13 is connected to the gas inlet 16 through a joint 15 connected to the case 14. The tube head outside the circumference of the spring-shaped Bourdon tube is welded and sealed to prevent leakage, and the first pointer 12 is welded at the same time. The greater the gas pressure inside the hollow spring-shaped Bourdon tube, the greater the deformation of the Bourdon tube, and the greater the deflection of the pointer welded to the Bourdon tube caused by the outward expansion of the spring-shaped Bourdon tube, indicating that the gas pressure is greater.

[0004] like Figure 2 The shown bow-shaped Bourdon tube pointer barometer 2 (radial pointer barometer) has a bow-shaped Bourdon tube 23 which is hollow, one end of which is connected to the gas inlet and fixed to the bottom plate of the barometer, and the other end of which is welded and sealed to prevent leakage, and a movable connecting rod 24 is installed. The greater the gas pressure in the hollow bow-shaped Bourdon tube 23, the greater the deformation of the bow-shaped Bourdon tube 23, and the greater the deflection of the second pointer 22 driven by the connecting rod 24, indicating that the gas pressure is greater, which is displayed on the second scale plate 21.

[0005] The disadvantages of the above two pointer-type barometers are that they have single functions and require manual observation to check the air pressure, which cannot keep up with the development of intelligent application fields in the information age.

[0006] like Figure 3The semiconductor electronic barometer 3 (diffused silicon pressure sensor barometer) shown in the figure has a working principle based on semiconductor pressure sensing technology. The core component is a semiconductor pressure sensor, which is composed of a low-pressure chamber 31, a high-pressure chamber 33, a silicon cup 32, a silicon diaphragm 37, a diffusion resistor 36, a first lead 34, a second lead 38, etc. The gas enters the sensor from the second air inlet 35, and the sensor converts the pressure received into an electrical signal, which is displayed in digital form after being amplified by the circuit board 39, analog-to-digital conversion, MCU, etc. The disadvantage of this pressure gauge is that it is costly, especially in MPa (megapascal) high pressure occasions. The semiconductor pressure sensor technology is extremely difficult to implement, resulting in high prices and exponential increases in cost prices. Summary of the invention

[0007] The purpose of the present invention is to provide an electronic barometer and a pressure measuring method, which are used to solve the problems that the pointer barometer in the prior art has a single function and is not suitable for intelligent applications, and the semiconductor electronic barometer has a high cost in high-pressure situations.

[0008] The present invention solves the above problems through the following technical solutions:

[0009] An electronic barometer comprises a barometer dial and a barometer base, wherein the barometer dial comprises a circuit board, a pointer electrode and a Bourdon tube, wherein the circuit board is provided with an MCU microprocessor, a signal detection circuit and a plurality of PCB scale electrodes evenly spaced and distributed in an arc shape, wherein the signal detection circuit and the plurality of PCB scale electrodes are electrically connected to the input and output ports of the MCU microprocessor respectively, wherein the pointer electrode is electrically connected to the signal input end of the signal detection circuit through the Bourdon tube and a metal shell of the electronic barometer, wherein the pointer electrode is fixed to the Bourdon tube or linked to the Bourdon tube; wherein the pointer electrode and the Bourdon tube are both made of conductive metal materials.

[0010] Furthermore, the pointer electrode and the Bourdon tube are fixed by welding.

[0011] Furthermore, the pointer electrode is linked to the Bourdon tube or a connecting rod mechanism connected to the Bourdon tube.

[0012] Furthermore, the pointer electrode and the PCB scale electrode match in shape.

[0013] Furthermore, the height difference between the pointer electrode and the PCB scale electrode is 0.3 mm to 1 mm.

[0014] Furthermore, the signal detection circuit includes a filtering unit and an amplifying unit, wherein the filtering unit is used to receive the signal of the pointer electrode and filter it before inputting it into the amplifying unit, and the amplifying unit amplifies the input signal and then inputs it into the input / output port (also called I / O port) of the MCU microprocessor. The signal filtering and amplifying circuit is not limited to this method.

[0015] Furthermore, one of the pointer electrode and the PCB scale electrode is a pulse signal transmitting port, and the other is a pulse signal receiving port.

[0016] Furthermore, the MCU microprocessor is also electrically connected to one or more of a liquid crystal display module, a communication module, a temperature detection module, an alarm module, and a safety automatic control module.

[0017] The air pressure measurement method implemented by using the electronic barometer comprises:

[0018] The MCU microprocessor outputs pulse signals to each PCB scale electrode in sequence starting from the first PCB scale electrode; or outputs pulse signals in reverse order starting from the last PCB scale electrode, or outputs pulse signals in a sequence that can shorten the time for determining the pointer position (for example, starting from the middle PCB scale electrode);

[0019] The MCU microprocessor receives the pulse signal fed back by the pointer electrode, and determines which PCB scale electrode output pulse signal matches the pointer electrode according to the signal strength, thereby determining the position of the pointer electrode;

[0020] The current pressure value is calculated based on the full bias pressure of the electronic barometer and the number of PCB scale electrodes combined with the position of the pointer electrode.

[0021] Furthermore, the MCU microprocessor also determines the coupling signal strength between the pointer electrode and a plurality of PCB scale electrodes according to the pulse signal fed back by the pointer electrode, and thereby derives the position of the pointer electrode between two PCB scale electrodes.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] (1) The present invention avoids the design concept of using semiconductor pressure sensors in existing electronic multifunctional barometers, and designs a multifunctional electronic barometer with simple structure and low cost, which has a very superior cost performance in the field of MPa-level high pressure applications.

[0024] (2) The present invention does not adopt the expensive semiconductor pressure sensor solution. Instead, it uses the principle of the Bourdon tube linkage pointer deflection of the traditional pointer pressure gauge with low price and very mature technology, designs a PCB scale electrode to replace the dial of the original pointer barometer, and designs a pointer electrode with a larger area to replace the pointer of the original pointer barometer. The relative position of the pointer on the dial is determined by sending and receiving signals between the scale electrode and the pointer electrode, so as to calculate the pressure and display it in digital form.

[0025] (3) The present invention is based on MCU design, which can expand information exchange communication, alarm, and use pressure to control related intelligent devices, thereby realizing the intelligence of air pressure monitoring application fields and improving the safety level; it can also set dangerous pressure value thresholds to automatically and timely control and shut down related equipment to improve safety.

[0026] (4) The pointer-type barometer has good reliability and stability. The present invention utilizes the Bourdon tube-linked pointer deflection principle to realize an electronic barometer, which has high stability and reliability. Compared with semiconductor pressure sensors, it can be used in high-pressure and ultra-high-pressure environments, with low cost and high cost-performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of a spring-shaped Bourdon tube pointer-type barometer in the prior art; wherein (a) is a schematic diagram of the head of the spring-shaped Bourdon tube pointer-type barometer, and (b) is a schematic diagram of the bottom of the spring-shaped Bourdon tube pointer-type barometer;

[0028] Figure 2 Schematic diagram of a bow-shaped Bourdon tube pointer type barometer in the prior art; wherein (a) is a schematic diagram of the head of the bow-shaped Bourdon tube pointer type barometer, and (b) is a schematic diagram of the bottom of the bow-shaped Bourdon tube pointer type barometer;

[0029] Figure 3 It is a schematic diagram of a semiconductor electronic barometer in the prior art;

[0030] Figure 4 It is a schematic diagram of the dial structure of an electronic barometer according to a first specific embodiment of the present invention;

[0031] Figure 5 A schematic diagram of the dial structure of an electronic barometer according to a second specific embodiment of the present invention;

[0032] Figure 6 A schematic diagram of the circuit principle of the relevant parts of the electronic barometer of the present invention;

[0033] Figure 7 It is a schematic diagram of the working principle of the electronic barometer in the present invention;

[0034] Among them, 1-spring-shaped Bourdon tube pointer barometer; 11-first dial; 12-first pointer; 13-spring-shaped Bourdon tube; 14-case; 15-connector; 16-first air inlet; 2-bow-shaped Bourdon tube pointer barometer; 21-second dial; 22-second pointer; 23-bow-shaped Bourdon tube; 24-connecting rod; 3-semiconductor electronic barometer; 31-low-pressure cavity; 32-silicon cup; 33-high-pressure cavity; 34-first lead; 35-second air inlet; 36-diffusion resistor; 37-silicon diaphragm; 38-second lead; 39-circuit board; 4-barometer dial A; 41-pointer electrode A; 42-PCB scale electrode A; 43-Bourdon tube A; 5-barometer dial B; 51-PCB scale electrode B; 52-pointer electrode B; IC1-MCU microprocessor; IC2-operational amplifier. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0036] Embodiment 1:

[0037] Combined with Figure 4 As shown, an electronic barometer includes a barometer dial A4 and a barometer base, the barometer dial A4 includes a circuit board, a pointer electrode A41 and a Bourdon tube A43, the circuit board is provided with an MCU microprocessor IC1, a signal detection circuit and a plurality of PCB scale electrodes A42 evenly spaced and distributed in an arc shape, the signal detection circuit and the plurality of PCB scale electrodes A42 are electrically connected to the input and output ports of the MCU microprocessor IC1, respectively, the pointer electrode A41 is electrically connected to the signal input end of the signal detection circuit through the Bourdon tube A43 and the metal shell of the electronic barometer, the pointer electrode A41 is fixed to the Bourdon tube A43, and the pointer electrode A41 and the Bourdon tube A43 are optionally fixed by welding; the pointer electrode A41 and the Bourdon tube A43 are both made of conductive metal materials and can conduct electricity.

[0038] The present invention improves the gauge head of the spring-shaped Bourdon tube pointer-type barometer in the prior art. Figure 1 The same as (b). In the present invention, the Bourdon tube is still hollow, the tube head at the center of the Bourdon tube is connected to the gas inlet, the tube head outside the circumference of the Bourdon tube is welded and sealed to prevent leakage, and the pointer electrode A41 is welded at the same time. The greater the gas pressure in the hollow Bourdon tube, the greater the deformation of the Bourdon tube, the greater the deflection of the pointer welded to the Bourdon tube caused by the outward expansion of the spring-shaped Bourdon tube, indicating that the gas pressure is greater.

[0039] Working principle:

[0040] The dial of the pointer-type barometer is replaced by a printed circuit board (PCB for short). Multiple mutually insulated PCB conductive copper foil electrodes, namely PCB scale electrodes A42, are designed on the PCB. These PCB scale electrodes A42 are respectively connected to different I / O (input and output pins) ports of the MCU. The pointer that is deformed and deflected in conjunction with the Bourdon tube according to the air pressure is designed as a pointer electrode A41. The number of PCB scale electrodes A42 is not necessarily a fixed value. It is adapted to local conditions according to the different sizes of the barometer and the desired measurement resolution. Figure 4 Because the spring-shaped Bourdon tube barometer has a small full deflection angle, 15 scale electrodes are designed in the schematic diagram. Figure 5 The mid-bow Bourdon tube barometer has a large full deflection angle, so 25 scale electrodes are designed in the schematic diagram. The pointer electrode A41 is above the PCB scale electrode A42 and deflects proportionally as the air pressure affects the deformation of the Bourdon tube. The height difference between the PCB scale electrode A42 and the pointer electrode A41 is preferably between 0.3 and 1 mm. During the product production process, it is necessary to ensure that the two cannot directly contact each other to avoid friction hindering the deflection of the pointer and affecting the measurement accuracy.

[0041] PCB scale electrode A42 is designed as a pulse signal transmitting port. Pointer electrode A41 is designed as a pulse signal receiving port. It can also be the other way around, PCB scale electrode A42 is designed as a receiving port, and pointer electrode A41 is designed as a transmitting port, but this method makes the signal amplification circuit at the receiving end more complicated. This principle description uses PCB scale electrode A42 designed as a pulse signal transmitting port and pointer electrode A41 designed as a pulse signal receiving port to describe its working principle. Pointer electrode A41 and Bourdon tube A43 are both conductive metal materials, and the conductive path is connected to the input end of the signal detection circuit on the circuit board through the metal shell of the barometer.

[0042] The circuit diagram of the present invention is as follows Figure 6 As shown, Figure 6 Only the circuit schematic diagram related to the present invention is shown. By electrically connecting the MCU microprocessor IC1 with one or more of the LCD display module, communication module, temperature detection module, alarm module, and safety automatic control module, functions such as LCD display, communication, temperature detection, alarm, and safety automatic control can be realized to adapt to different application scenarios.

[0043] Figure 6 The MCU microprocessor IC1 can be selected in different models according to different actual application occasions. In this schematic diagram, the number of PCB scale electrodes A42 is 15, and a 20-pin MCU is selected. If the number of PCB scale electrodes is 25 or more, an MCU with more pins is selected. Figure 6The signal detection circuit in the figure lists a filter circuit, an operational amplifier IC2 and related circuits, which is a schematic diagram of the filter amplification processing circuit principle of the pointer electrode end coupling receiving signal. Different amplification processing circuits can be selected for different application occasions. The above component selection and circuit form do not affect the description of the key technology of the present invention.

[0044] The main waveforms of the working principle of the circuit part of the present invention are shown as follows Figure 7 As shown, the PCB scale electrode A42 starts to output pulse groups from P1 and continues to poll and scan at P15. The waveforms not drawn are omitted in the figure. The pointer electrode A41 is shown to be above P14 of the PCB scale electrode A42. Therefore, it can be seen from the waveform diagram that the receiving end of the pointer electrode A41 can only output pulses after induction reception and amplification when the P14 of the PCB scale electrode A42 outputs the waveform. Based on this, the MCU determines that the barometer pointer is at the P14 position and thus calculates the corresponding pressure.

[0045] The pulse frequency of the pulse output of the PCB scale electrode is generally selected between 10KHz and 1MHz, which is called the operating frequency. According to the different sizes of barometers and the different areas of electrodes, the operating frequency is adjusted by software, with the goal of making the pointer electrode receiving end get a better signal waveform. The scale electrode is defined as the transmitting end, which can also be called the transmitting electrode. The pointer electrode is defined as the receiving end, which can also be called the receiving electrode. A capacitor is actually formed between the two electrodes, which can also be called a coupler. The larger the area of ​​each transmitting electrode and receiving electrode designed, the larger the equivalent capacitance, the lower the operating frequency can be selected, and the filtering and amplification circuits are simpler. The smaller the area of ​​each transmitting electrode and receiving electrode designed, the smaller the equivalent capacitance, the stronger the coupling high-frequency capability, and the operating frequency needs to be selected higher, but the filtering and amplification circuits are relatively complex, and the cost will increase appropriately.

[0046] The key technology of the present invention is to use an MCU microprocessor (MCU for short) to drive multiple scale electrodes, transmit pulse signals in a scanning manner in turn, and determine the accurate position of the current deflection of the pointer through the received signal of the pointer electrode. The received signal is added to the MCU for analog-to-digital conversion (also called AD conversion) after filtering and amplification, and the relative strength of the signal received by the pointer electrode is used to calculate the air pressure. Then the MCU drives the liquid crystal display to display the air pressure value in a digital way, and the air pressure value can also be transmitted to other user-end devices by wired or wireless means. It can also realize automatic alarm for undervoltage and overvoltage or automatically take safety precautions in emergency situations.

[0047] You can also reverse the transmitting end and the receiving end, load the MCU transmission signal to the pointer electrode, and then use the scanning method to detect which scale electrode receives the signal and the relative size of the signal to determine the exact position of the current deflection of the pointer. The following description continues to explain the working principle using the former as an example.

[0048] Figure 4 The first specific implementation mode of the present invention is shown, in which the pointer electrode A41 is above the PCB scale electrode A42, with a height difference of 0.3 to 1 mm. The overlap of the areas of the two electrodes is actually the principle of a capacitor. The size of the capacitance is related to the height difference and the overlap of the areas of the two electrodes. In order to increase the overlap area of ​​the pointer electrode and the PCB scale electrode, the shapes of the pointer electrode and the PCB scale electrode described in the present invention match. The capacitor has an AC signal coupling function, so the pulse signal emitted from the scale electrode is coupled to the pointer electrode through the capacitance formed between the two electrodes. It can also be understood that the scale electrode emits a signal, and the pointer electrode above it senses the received signal. The signal coupled to the pointer electrode is filtered and amplified, and then added to the MCU for AD conversion to measure the relative signal size.

[0049] The further working principle of the present invention is that the larger the overlap area between the pointer electrode and the scale electrode below, the stronger the signal coupled to the electrode, and the larger the AD conversion value of the MCU. For example: Figure 4 As shown in the figure, the pointer electrode is directly above the scale electrode "P14". When the pulse signal from the transmitter scans the scale electrode "P14", the signal coupled to the pointer electrode is the strongest. When scanning the left and right neighboring electrodes "P13" and "P15", the signals coupled to the pointer electrode are very weak, or even zero, as shown in the waveform. Figure 7 As shown. Then, based on the measurement results, the MCU can determine that the pointer electrode is facing the scale electrode "P14". Figure 4 The full bias design shown has 15 electrodes. If the full bias pressure represents 30MPa (megapascals), then Figure 4 The pointer electrode is at "P14", and the MCU measurement result is determined to be 28MPa (megapascals). Other transmitting electrodes such as P1, P2...P13, P15 are far away from the receiving electrode or have no overlapping relationship, so there is no coupling signal or the coupling signal is very small. For example: Figure 5 As shown, the pointer electrode is located above the middle of "P10" and "P11" of the scale electrodes. When the pulse signal from the transmitting end scans "P10" of the scale electrode, the signal coupled to the pointer electrode is relatively medium strong. When the pulse signal from the transmitting end scans "P11" of the scale electrode, the signal coupled to the pointer electrode is also relatively medium strong. Then, based on the measurement results, the MCU can determine that the pointer electrode is located between the "P10" and "P11" scales. Figure 5The full bias is designed with 25 scale electrodes. If the full bias pressure represents 50MPa (megapascals), then Figure 5 The pointer electrode is shown to be between the scales of "P10" and "P11", and the measurement result is determined to be 21MPa (megapascals). Other transmitting electrodes such as P1, P2...P9, P12...P25 are far away from the pointer electrode or have no overlapping relationship, so there is no coupling signal or the coupling signal is very small. Through the relative size of the MCU measurement value, it is also possible to further determine whether the pointer electrode overlaps more with "P10" or "P11", that is, to determine which scale electrode the pointer is closer to and which scale electrode it is more coupled with, further improving the pressure measurement resolution.

[0050] The further working principle of the present invention is that the height difference of the pointer electrode above the scale electrode is between 0.3 and 1 mm, and the inconsistency of this height difference will affect the capacitance formed between the two electrodes, thereby affecting the strength of the signal coupling. However, because the receiving end uses the analog-to-digital conversion method of the MCU to convert the size of the analog signal received by the coupling into the size of the digital quantity. Therefore, the relative position of the pointer electrode above the scale electrode is judged by comparing the relative size of this digital quantity. Therefore, there is no need to strictly require the height accuracy of the pointer electrode above the scale electrode and the high consistency in mass production.

[0051] In summary, the present invention utilizes the principle of a pointer barometer and replaces the dial of the pointer barometer with multiple scale electrodes designed on a printed circuit board. These scale electrodes are PCB conductive copper foils that are insulated from each other. A pulse signal is output on each scale electrode in a scanning manner, and a pointer that deflects proportionally with the air pressure in conjunction with a Bourdon tube is designed as a pointer electrode. The pointer electrode receives the pulse signal emitted by the scale electrode by the capacitive coupling between the pointer electrode and the scale electrode. The relative position of the pointer on the dial is thus determined, and the MCU calculates the corresponding pressure.

[0052] The number of scale electrodes in the present invention can be flexibly designed according to the specific product size, the specification parameters of the selected Bourdon tube, the maximum measurement range, the desired measurement accuracy, etc.

[0053] Embodiment 2:

[0054] Figure 5A second specific implementation is shown, an electronic barometer, including a barometer dial B5 and a barometer base, the barometer dial B5 includes a circuit board, a pointer electrode B52, the circuit board is provided with an MCU microprocessor IC1 (in this case, IC1 needs to use an MCU with a large number of pins), a signal detection circuit and a plurality of PCB scale electrodes B51 evenly spaced and distributed in an arc shape, the signal detection circuit and the plurality of PCB scale electrodes B51 are electrically connected to the input and output ports of the MCU microprocessor IC1, respectively, the circuit board is provided with a scale plate matching the PCB scale electrode B51, the pointer electrode B52 is linked to the Bourdon tube through a connecting rod (the connection structure is the same as Figure 2 (b)), the difference is that the pointer electrode B52, the connecting rod and the Bourdon tube in the present invention are all made of conductive metal materials.

[0055] The electronic barometer in this embodiment is a partial improvement on the bow-shaped Bourdon tube pointer barometer in the prior art. The only difference from Embodiment 1 is that one is a spring-shaped Bourdon tube and the other is a bow-shaped Bourdon tube. Similarly, the bow-shaped Bourdon tube is hollow, and the tube head at one end of the Bourdon tube is connected to the gas inlet and fixed to the chassis of the barometer. The other end of the Bourdon tube is welded and sealed to prevent leakage, and a movable connecting rod is installed at the same time. The greater the gas pressure in the hollow Bourdon tube, the greater the deformation of the Bourdon tube, and the greater the deflection of the pointer driven by the connecting rod, indicating that the gas pressure is greater. The working principle is the same as that of Embodiment 1.

[0056] Embodiment 3:

[0057] The air pressure measurement method implemented by using the electronic barometer described in Example 1 or Example 2 includes:

[0058] The MCU microprocessor outputs pulse signals to each PCB scale electrode in sequence starting from the first PCB scale electrode; or outputs pulse signals in reverse order starting from the last PCB scale electrode, or outputs pulse signals in a sequence that can shorten the time for determining the position of the pointer electrode;

[0059] The MCU microprocessor receives the pulse signal fed back by the pointer electrode, and determines which PCB scale electrode output pulse signal matches the pointer electrode according to the signal strength, thereby determining the position of the pointer electrode;

[0060] The current pressure value is calculated based on the full bias pressure of the barometer and the number of PCB scale electrodes combined with the position of the pointer electrode.

[0061] Furthermore, the MCU microprocessor also determines the relative strength of the coupling signals between the pointer electrode and the plurality of PCB scale electrodes according to the pulse signal fed back by the pointer electrode, and thereby derives the position of the pointer electrode between the two PCB scale electrodes.

[0062] Although the present invention is described herein with reference to the illustrative embodiments of the present invention, the above embodiments are only preferred embodiments of the present invention, and the embodiments of the present invention are not limited to the above embodiments. It should be understood that those skilled in the art can design many other modifications and embodiments, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. An electronic barometer, comprising a barometer dial and a barometer base, characterized in that: The barometer dial includes a circuit board, a pointer electrode and a Bourdon tube. The circuit board is provided with an MCU microprocessor, a signal detection circuit and a plurality of PCB scale electrodes evenly spaced in an arc shape. The signal detection circuit and the plurality of PCB scale electrodes are electrically connected to the input and output ports of the MCU microprocessor, respectively. The pointer electrode is electrically connected to the signal input end of the signal detection circuit through the Bourdon tube and the metal shell of the electronic barometer. The pointer electrode is fixed to the Bourdon tube or linked to the Bourdon tube. The pointer electrode and the Bourdon tube are both made of conductive metal materials.

2. An electronic barometer according to claim 1, characterized in that: The pointer electrode and the Bourdon tube are fixed by welding.

3. An electronic barometer according to claim 1, characterized in that: The linkage between the pointer electrode and the Bourdon tube is achieved through a connecting rod connected to the pointer electrode and the Bourdon tube at both ends respectively.

4. An electronic barometer according to claim 1, characterized in that: The pointer electrode and the PCB scale electrode match in shape.

5. An electronic barometer according to claim 1, characterized in that: The height difference between the pointer electrode and the PCB scale electrode is 0.3 mm to 1 mm.

6. An electronic barometer according to claim 1, characterized in that: The signal detection circuit includes a filtering unit and an amplifying unit. The filtering unit is used to receive the signal of the pointer electrode and input the signal to the amplifying unit after filtering. The amplifying unit amplifies the input signal and inputs it to the input and output port of the MCU microprocessor.

7. An electronic barometer according to claim 1, characterized in that: One of the pointer electrode and the PCB scale electrode is a pulse signal transmitting port, and the other is a pulse signal receiving port.

8. An electronic barometer according to claim 1, characterized in that: The MCU microprocessor is also electrically connected to one or more of a liquid crystal display module, a communication module, a temperature detection module, an alarm module, and a safety automatic control module.

9. A method for measuring air pressure using an electronic barometer as claimed in any one of claims 1 to 8, characterized in that: include: The MCU microprocessor outputs pulse signals to each PCB scale electrode in sequence starting from the first PCB scale electrode; Or output the pulse signal in reverse order starting from the last PCB scale electrode, or output the pulse signal in a sequence that can shorten the time for determining the position of the pointer electrode; The MCU microprocessor receives the pulse signal fed back by the pointer electrode, and determines which PCB scale electrode output pulse signal matches the pointer electrode according to the signal strength, thereby determining the position of the pointer electrode; The current pressure value is calculated based on the full bias pressure of the barometer and the number of PCB scale electrodes combined with the position of the pointer electrode.

10. The air pressure measurement method according to claim 9, characterized in that: The MCU microprocessor also determines the relative strength of the coupling signals between the pointer electrode and a plurality of PCB scale electrodes according to the pulse signal fed back by the pointer electrode, and thereby derives the position of the pointer electrode between two PCB scale electrodes.

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