A double-vibrating-beam differential metal-based two-stage amplification quartz resonant pressure sensing structure

Abstract

The application discloses a double-vibration-beam differential metal-based two-stage amplification quartz resonant pressure sensing structure, relates to the technical field of micro-mechanical electronic (MEMS) pressure measuring devices, and comprises a pressure probe structure element, wherein the pressure probe structure element is connected with a metal flexible lever structure, the metal flexible lever structure is connected with a first quartz double-end fixed support vibration beam and a second quartz double-end fixed support vibration beam, and the first quartz double-end fixed support vibration beam and the second quartz double-end fixed support vibration beam are arranged in a differential mode. The application realizes differential loading at the mechanical structure level, effectively suppresses the temperature common-mode drift and the influence of packaging residual stress, and improves the measurement precision and stability.

Description

Technical Field

[0001] This invention relates to the field of microelectromechanical (MEMS) pressure measurement device technology, specifically to a dual-beam differential metal-based two-stage amplified quartz resonant pressure-sensitive structure. Background Technology

[0002] Quartz resonant pressure sensors are widely used in aerospace, oil well logging, and high-precision pressure measurement due to their high precision, high stability, and good long-term reliability. Their basic working principle is based on the application of pressure to an elastic sensitive structure, causing axial stress changes in the resonant element, which in turn causes a change in the resonant frequency. High-precision measurement of the pressure signal can be achieved by detecting the resonant frequency.

[0003] In existing technologies, to improve the sensitivity of pressure-sensitive structures, a mechanical amplification structure consisting of a metal elastic diaphragm, a pressure transmission probe, and a flexible lever is typically used. This structure amplifies the minute displacement caused by pressure in two stages and applies it to a quartz resonant beam, causing axial stress changes in the beam and thus converting the pressure signal into a resonant frequency. For example, the patent application titled "Quartz Resonant Pressure Sensor Based on a Single Pressure Conversion Element" (publication number CN116046220A) uses a quartz resonant pressure sensor as the core measuring element. It achieves high-precision pressure measurement by using pressure to induce stress changes in the quartz resonator.

[0004] However, most existing metal-based two-stage amplified quartz resonant pressure-sensitive structures employ a single-beam structure, meaning that only one quartz resonant beam is placed between the output end of the flexible lever and the fixed reference end. When the ambient temperature changes or residual stress is generated during the packaging process, this beam is easily affected by common-mode stress, which leads to resonant frequency drift and reduces the stability and long-term accuracy of pressure measurement.

[0005] Therefore, it is necessary to propose a quartz resonant pressure-sensitive structure that can suppress the effects of temperature common-mode stress and packaging residual stress in order to improve the accuracy and stability of pressure measurement. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, the present invention aims to provide a dual-beam differential metal-based two-stage amplified quartz resonant pressure-sensitive structure. By setting two fixed reference ends on the same metal flexible lever structure, the two vibrating beams share the same output end displacement and form axial stresses in opposite directions, thereby realizing differential frequency output and effectively suppressing conjugate interference such as temperature drift caused by thermal effects.

[0007] To achieve the above objectives, the technical solution adopted by this invention is as follows: A differential metal-based two-stage amplified quartz resonant pressure-sensitive structure with dual vibrating beams includes a pressure probe structural element 1, a metal flexible lever structure 2, a first quartz double-ended fixed vibrating beam 3, and a second quartz double-ended fixed vibrating beam 4. The pressure probe structural element 1 and the metal flexible lever structure 2 are connected, and the first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 are connected to the metal flexible lever structure 2. The first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 are configured as differential vibrating beams.

[0008] The pressure probe structural element 1 includes a pressure probe sensitive membrane structure. A metal pressure sensitive diaphragm 1a is disposed below the pressure probe sensitive membrane structure. A pressure transmission probe 1b is disposed below the metal pressure sensitive diaphragm 1a. A diaphragm support structure 1c is connected above the metal pressure sensitive diaphragm 1a. A stress isolation structure 1d is machined on the outside of the diaphragm support structure 1c. The upper part of the diaphragm support structure 1c is fixedly connected to the lower part of the pressure probe housing support structure 1e to form a pressure chamber. A fixing thread 1f is disposed in the center of the upper part of the pressure probe housing support structure 1e. A pressure-feeding hole 1g is disposed in the center of the upper part of the pressure probe housing support structure 1e to connect the inside and outside of the pressure chamber.

[0009] The metal flexible lever 2 includes a flexible hinge structure 2b connected to the pressure input end 2a, a pressure output end 2c located on one side of the flexible hinge, a first fixed reference end 2d rigidly connected to the lever body connected to the flexible hinge structure, and a second fixed reference end 2e rigidly connected to the lever body; the first fixed reference end 2d and the second fixed reference end 2e are located on both sides of the pressure output end 2c.

[0010] The metal flexible lever pressure input end 2a is coaxially connected to the pressure transmission probe 1b; the first quartz double-ended fixed-supported vibrating beam 3 spans between the pressure output end 2c and the first fixed reference end 2d; the second quartz double-ended fixed-supported vibrating beam 4 spans between the pressure output end 2c and the second fixed reference end 2e; according to claim 2, the quartz resonant pressure sensitive structure is characterized in that: the metal flexible lever 2 includes a flexible hinge structure 2b connected to the pressure input end 2a, a pressure output end 2c located on one side of the flexible hinge, a first fixed reference end 2d rigidly connected to the lever body connected to the flexible hinge structure 2b, and a second fixed reference end 2e rigidly connected to the lever body; the first fixed reference end 2d and the second fixed reference end 2e are respectively located on both sides of the pressure output end 2c; the metal flexible lever pressure input end 2a is provided with a positioning hole 2f; the metal flexible lever pressure output end 2c is provided with an output end positioning groove 2g; the first fixed reference end 2d is provided with a first positioning groove 2h; and the second fixed reference end 2e is provided with a second positioning groove 2i. The first quartz double-ended fixed tuning fork 3 is located on the side of the pressure output end 2c of the metal flexible lever and the first fixed reference end 2d of the flexible lever. The quartz double-ended fixed tuning fork 3 obtains the pressure signal by sensing the deformation of the metal pressure-sensitive diaphragm 1a and transmitting it through the metal flexible lever 2. The second quartz double-ended fixed tuning fork 4 is located on the side of the pressure output end 2c of the metal flexible lever and the second fixed reference end 2e of the flexible lever. The second quartz double-ended fixed tuning fork 4 obtains the pressure signal by sensing the deformation of the metal pressure-sensitive diaphragm 1a and transmitting it through the metal flexible lever 2. When pressure is applied to the metal pressure-sensitive diaphragm 1a, it is amplified by the pressure transmission probe 1b and the flexible hinge structure 2b, causing the pressure output end 2c to be displaced relative to the two fixed reference ends. This causes the first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 to generate axial stresses in opposite directions, thereby forming a differential frequency output.

[0011] The metal pressure-sensitive diaphragm 1a is circular, and the pressure transmission probe 1b is arranged at the center of the metal pressure-sensitive diaphragm 1a. The pressure transmission probe 1b is concentric with the positioning hole 2f provided at the pressure input end 2a of the metal flexible lever. The two ends of the first quartz double-ended fixed tuning fork 3 are respectively aligned with the first positioning groove 2h provided on the side of the pressure output end 2c of the metal flexible lever and the first fixed reference end 2d of the flexible lever.

[0012] The first quartz double-ended fixed tuning fork 3 includes connecting parts 3a and 3b at both ends. The lower surfaces of the connecting parts 3a and 3b are connected to the side surfaces of the pressure output end 2c and the first fixed reference end 2d, and are aligned with the first positioning groove 2h provided on the side surfaces of the pressure output end 2c and the first fixed reference end 2d. The connecting parts are connected by two symmetrical tuning fork arms 3d, with a slit 3c between the two tuning fork arms. Electrodes are provided around the surface of the two tuning fork arms 3d, and the electrodes are electrically connected to each other for the tuning fork arms 3d to start oscillating. Under the action of the inverse piezoelectric effect, when an alternating voltage is applied, the tuning fork arms 3d are in a preset vibration mode. A detection electrode is provided on the upper surface of the connecting part 3a at one end, and a solder pad connected to an external circuit is provided on the upper surface of the connecting part 3b at the other end. The solder pad is connected to the PCB board through a gold wire.

[0013] The diaphragm support structure 1c and the pressure probe housing support structure 1e are arranged in a coaxial circular shape.

[0014] The first fixed reference end 2d and the second fixed reference end 2e are arranged symmetrically about the central axis of the pressure output end 2c.

[0015] The first quartz double-ended fixed vibration beam 3 and the second quartz double-ended fixed vibration beam 4 are located in the same plane and are arranged in a mirror-symmetric manner.

[0016] The first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 have the same structure.

[0017] When the first quartz double-ended fixed vibrating beam 3 generates axial tensile stress under the action of displacement at the output end, the second quartz double-ended fixed vibrating beam 4 simultaneously generates axial compressive stress.

[0018] An equivalent length installation spacing is formed between the first fixed reference end 2d, the second fixed reference end 2e, and the pressure output end 2c to ensure that the two vibrating beams generate equal reverse strain under the displacement of the output end.

[0019] The metal pressure-sensitive diaphragm 1a is integrated with the diaphragm support structure 1c.

[0020] The pressure transmission probe 1b and the metal pressure-sensitive diaphragm 1a are integrated into one unit.

[0021] The diaphragm support structure 1c and the pressure probe housing support structure 1e are connected by welding or bonding, and the pressure transmission probe 1b and the pressure input end 2a are connected as one unit by welding or bonding.

[0022] The pressure output end 2c, the first fixed reference end 2d, and the second fixed reference end 2e are at the same height.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) Since the present invention sets two fixed reference ends on the metal flexible lever structure, and sets a first quartz double-ended fixed vibrating beam and a second quartz double-ended fixed vibrating beam between the pressure output end and the two fixed reference ends respectively, the two vibrating beams generate axial stresses in opposite directions under the same output displacement, thereby forming a differential resonant frequency output structure, which can effectively suppress common mode interference caused by temperature changes and packaging residual stress, and improve the stability of pressure measurement.

[0024] (2) Since the two quartz double-end fixed vibrating beams are arranged in a mirror symmetry and share the same pressure output end displacement, the two vibrating beams generate equal reverse strain during operation, which can significantly improve the sensitivity and signal-to-noise ratio of the pressure signal output.

[0025] (3) Since the present invention adopts a two-stage mechanical amplification structure consisting of a metal pressure-sensitive diaphragm, a pressure transmission probe and a metal flexible lever, it can effectively amplify the small displacement caused by pressure, increase the amplitude of axial stress change of the vibrating beam, and thus further improve the pressure measurement resolution.

[0026] (4) The present invention has a simple structure and is easy to assemble. It is suitable for the sensitive structure design of high-precision quartz resonant pressure sensors and has good engineering application value. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention.

[0028] Figure 2 This is a perspective view of the pressure probe structure element according to an embodiment of the present invention.

[0029] Figure 3 This is a cross-sectional view of the pressure probe structure element according to an embodiment of the present invention.

[0030] Figure 4 This is a perspective view of a flexible metal lever according to an embodiment of the present invention.

[0031] Figure 5 This is a perspective view of a quartz double-ended fixed tuning fork according to an embodiment of the present invention. Detailed Implementation

[0032] The present invention will now be described in detail with reference to the embodiments and accompanying drawings.

[0033] Reference Figure 1 A differential metal-based two-stage amplified quartz resonant pressure-sensitive structure with dual vibrating beams includes a pressure probe structural element 1, a metal flexible lever structure 2, a first quartz double-end fixed vibrating beam 3, and a second quartz double-end fixed vibrating beam 4. The pressure probe structural element 1 and the metal flexible lever structure 2 are connected, and the first quartz double-end fixed vibrating beam 3 and the second quartz double-end fixed vibrating beam 4 are connected to the metal flexible lever structure 2. The first quartz double-end fixed vibrating beam 3 and the second quartz double-end fixed vibrating beam 4 are configured as differential vibrating beams.

[0034] Reference Figure 2 and Figure 3 The pressure probe structural element 1 includes a pressure probe sensitive membrane structure. A metal pressure sensitive diaphragm 1a is disposed below the pressure probe sensitive membrane structure. A pressure transmission probe 1b for transmitting diaphragm displacement is disposed below the metal pressure sensitive diaphragm 1a. A diaphragm support structure 1c is connected above the metal pressure sensitive diaphragm 1a. A stress isolation structure 1d for isolating installation and external stress is machined on the outside of the diaphragm support structure 1c. The upper part of the diaphragm support structure 1c is fixedly connected to the lower part of the pressure probe housing support structure 1e to form a pressure chamber. A fixing thread 1f is disposed in the center of the upper part of the pressure probe housing support structure 1e. A pressure tapping hole 1g is disposed in the center of the upper part of the pressure probe housing support structure 1e to connect the inside and outside of the pressure chamber.

[0035] Reference Figure 4The metal flexible lever 2 includes a flexible hinge structure 2b connected to the pressure input end 2a, a pressure output end 2c located on one side of the flexible hinge, a first fixed reference end 2d rigidly connected to the lever body connected to the flexible hinge structure 2b, and a second fixed reference end 2e rigidly connected to the lever body; the first fixed reference end 2d and the second fixed reference end 2e are respectively located on both sides of the pressure output end 2c; the metal flexible lever pressure input end 2a is provided with a positioning hole 2f; the metal flexible lever pressure output end 2c is provided with an output end positioning groove 2g; the first fixed reference end 2d is provided with a first positioning groove 2h; and the second fixed reference end 2e is provided with a second positioning groove 2i. The metal flexible lever pressure input end 2a is coaxially connected to the pressure transmission probe 1b; the first quartz double-ended fixed vibrating beam 3 is connected between the pressure output end 2c and the first fixed reference end 2d; the second quartz double-ended fixed vibrating beam 4 is connected between the pressure output end 2c and the second fixed reference end 2e.

[0036] The first quartz double-ended fixed tuning fork 3 is located on the side of the pressure output end 2c of the metal flexible lever and the first fixed reference end 2d of the flexible lever. The first quartz double-ended fixed tuning fork 3 obtains the pressure signal by sensing the deformation of the metal pressure-sensitive diaphragm 1a and transmitting it through the metal flexible lever 2.

[0037] The second quartz double-ended fixed tuning fork 4 is located on the side of the pressure output end 2c of the metal flexible lever and the second fixed reference end 2e of the flexible lever. The second quartz double-ended fixed tuning fork 4 obtains the pressure signal by sensing the deformation of the metal pressure-sensitive diaphragm 1a and transmitting it through the metal flexible lever 2.

[0038] When pressure is applied to the metal pressure-sensitive diaphragm 1a, it is amplified by the pressure transmission probe 1b and the flexible hinge structure 2b, causing the pressure output end 2c to be displaced relative to the two fixed reference ends. This causes the first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 to generate axial stresses in opposite directions, thereby forming a differential frequency output.

[0039] When the pressure-sensitive structure of this invention is in operation, an alternating voltage is used to excite the first quartz double-ended fixed-end vibrating beam 3 and the second quartz double-ended fixed-end vibrating beam 4. Due to the inverse piezoelectric effect, after being excited by the applied alternating voltage, the first quartz double-ended fixed-end vibrating beam 3 and the second quartz double-ended fixed-end vibrating beam 4 vibrate according to their predetermined natural mode shapes. When the pressure to be measured is applied above the metal pressure-sensitive diaphragm 1a, the metal pressure-sensitive diaphragm 1a is deformed by the force, causing the pressure transmission probe 1b below the metal pressure-sensitive diaphragm 1a to be displaced. The pressure transmission probe 1b pushes the metal... The pressure input end 2a of the flexible lever is displaced. After the displacement is proportionally converted by the flexible metal lever 2, the pressure output end 2c of the flexible metal lever and the first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 set at the fixed end will have a piezoelectric effect. This will cause the resonant frequency of the first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 to change. By detecting the resonant frequency of the first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4, which has a linear relationship with the pressure signal, the magnitude of the pressure to be measured can be detected.

[0040] The metal pressure-sensitive diaphragm 1a is circular, and the pressure transmission probe 1b is arranged at the center of the metal pressure-sensitive diaphragm 1a. The pressure transmission probe 1b is concentric with the positioning hole 2f provided at the pressure input end 2a of the metal flexible lever. The two ends of the first quartz double-ended fixed tuning fork 3 are respectively aligned with the first positioning groove 2h provided on the side of the pressure output end 2c of the metal flexible lever and the first fixed reference end 2d of the flexible lever.

[0041] Reference Figure 5 The first quartz double-ended fixed tuning fork 3 includes connecting parts 3a and 3b at both ends. The lower surfaces of the connecting parts 3a and 3b are connected to the side surfaces of the pressure output end 2c and the first fixed reference end 2d, and are aligned with the first positioning groove 2h provided on the side surfaces of the pressure output end 2c and the first fixed reference end 2d. The connecting parts are connected by two symmetrical tuning fork arms 3d, with a slit 3c between the two tuning fork arms. Electrodes are provided around the surface of the two tuning fork arms 3d, and the electrodes are electrically connected to each other for the tuning fork arms 3d to start oscillating. Under the action of the inverse piezoelectric effect, when an alternating voltage is applied, the tuning fork arms 3d are in a preset vibration mode. A detection electrode is provided on the upper surface of the connecting part 3a at one end, and a solder pad connected to an external circuit is provided on the upper surface of the connecting part 3b at the other end. The solder pad is connected to the PCB board through a gold wire.

[0042] The diaphragm support structure 1c and the pressure probe housing support structure 1e are arranged in a coaxial circular shape.

[0043] The first fixed reference end 2d and the second fixed reference end 2e are arranged symmetrically about the central axis of the pressure output end 2c.

[0044] The first quartz double-ended fixed vibration beam 3 and the second quartz double-ended fixed vibration beam 4 are located in the same plane and are arranged in a mirror-symmetric manner.

[0045] The first quartz double-ended fixed vibrating beam 3 and the second quartz double-ended fixed vibrating beam 4 have the same structure.

[0046] When the first quartz double-ended fixed vibrating beam 3 generates axial tensile stress under the action of displacement at the output end, the second quartz double-ended fixed vibrating beam 4 simultaneously generates axial compressive stress.

[0047] An equivalent length installation spacing is formed between the first fixed reference end 2d, the second fixed reference end 2e, and the pressure output end 2c to ensure that the two vibrating beams generate equal reverse strain under the displacement of the output end.

[0048] The metal pressure-sensitive diaphragm 1a is integrated with the diaphragm support structure 1c.

[0049] The pressure transmission probe 1b and the metal pressure-sensitive diaphragm 1a are integrated into one unit.

[0050] The diaphragm support structure 1c and the pressure probe housing support structure 1e are connected by welding or bonding, and the pressure transmission probe 1b and the pressure input end 2a are connected as one unit by welding or bonding.

[0051] The pressure output end 2c, the first fixed reference end 2d, and the second fixed reference end 2e are at the same height.

Claims

1. A dual-beam differential metal-based two-stage amplified quartz resonator pressure-sensitive structure, characterized in that, It includes a pressure probe structural element (1), a metal flexible lever structure (2), a first quartz double-ended fixed vibrating beam (3) and a second quartz double-ended fixed vibrating beam (4); the pressure probe structural element (1) and the metal flexible lever structure (2) are connected, and the first quartz double-ended fixed vibrating beam (3) and the second quartz double-ended fixed vibrating beam (4) are connected on the metal flexible lever structure (2), and the first quartz double-ended fixed vibrating beam (3) and the second quartz double-ended fixed vibrating beam (4) are set as differential.

2. The quartz resonant pressure-sensitive structure according to claim 1, characterized in that: The pressure probe structural element (1) includes a pressure probe sensitive membrane structure. A metal pressure sensitive diaphragm (1a) is disposed below the pressure probe sensitive membrane structure. A pressure transmission probe (1b) is disposed below the metal pressure sensitive diaphragm (1a). A diaphragm support structure (1c) is connected above the metal pressure sensitive diaphragm (1a). A stress isolation structure (1d) is processed on the outside of the diaphragm support structure (1c). The upper part of the diaphragm support structure (1c) is fixedly connected to the lower part of the pressure probe housing support structure (1e) to form a pressure chamber. A fixing thread (1f) is disposed in the center of the upper part of the pressure probe housing support structure (1e). A pressure tapping hole (1g) is disposed in the center of the upper part of the pressure probe housing support structure (1e) to connect the inside and outside of the pressure chamber.

3. The quartz resonant pressure-sensitive structure according to claim 2, characterized in that: The metal flexible lever (2) includes a flexible hinge structure (2b) connected to the pressure input end (2a), a pressure output end (2c) located on one side of the flexible hinge, a first fixed reference end (2d) rigidly connected to the lever body connected to the flexible hinge structure (2b), and a second fixed reference end (2e) rigidly connected to the lever body; the first fixed reference end (2d) and the second fixed reference end (2e) are located on both sides of the pressure output end (2c); the metal flexible lever pressure input end (2a) is provided with a positioning hole (2f); the metal flexible lever pressure output end (2c) is provided with an output end positioning groove (2g); the first fixed reference end (2d) is provided with a first positioning groove (2h); and the second fixed reference end (2e) is provided with a second positioning groove (2i).

4. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The metal flexible lever pressure input end (2a) is coaxially connected to the pressure transmission probe (1b); the first quartz double-ended fixed vibrating beam (3) is connected between the pressure output end (2c) and the first fixed reference end (2d); the second quartz double-ended fixed vibrating beam (4) is connected between the pressure output end (2c) and the second fixed reference end (2e). The first quartz double-ended fixed tuning fork (3) is located on the side of the pressure output end (2c) and the first fixed reference end (2d) of the flexible lever. The quartz double-ended fixed tuning fork (3) obtains a pressure signal by sensing the deformation of the metal pressure-sensitive diaphragm (1a) and transmitting it through the metal flexible lever (2). The second quartz double-ended fixed tuning fork (4) is located on the side of the pressure output end (2c) and the second fixed reference end (2e) of the flexible lever. The second quartz double-ended fixed tuning fork (4) obtains a pressure signal by sensing the deformation of the metal pressure-sensitive diaphragm (1a) and transmitting it through the metal flexible lever (2). When pressure is applied to the metal pressure-sensitive diaphragm (1a), it is amplified by the pressure transmission probe (1b) and the flexible hinge structure (2b) in two stages, causing the pressure output end (2c) to be displaced relative to the two fixed reference ends. This causes the first quartz double-ended fixed vibrating beam (3) and the second quartz double-ended fixed vibrating beam (4) to generate axial stresses in opposite directions, thereby forming a differential frequency output.

5. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The metal pressure-sensitive diaphragm (1a) is circular, and the pressure transmission probe (1b) is arranged at the center of the metal pressure-sensitive diaphragm (1a). The pressure transmission probe (1b) is concentric with the positioning hole (2f) provided on the pressure input end (2a) of the metal flexible lever. The two ends of the first quartz double-ended fixed tuning fork (3) are respectively aligned with the output end positioning groove (2g) provided on the side of the pressure output end (2c) of the metal flexible lever and the first positioning groove (2h) provided on the side of the first fixed reference end (2d) of the flexible lever. The two ends of the second quartz double-ended fixed tuning fork (4) are respectively aligned with the output end positioning groove (2g) provided on the side of the pressure output end (2c) of the metal flexible lever and the second positioning groove (2i) provided on the side of the second fixed reference end (2e) of the flexible lever.

6. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The first quartz double-ended fixed tuning fork (3) includes connecting parts (3a, 3b) at both ends. The lower surface of the connecting parts (3a, 3b) is connected to the side of the pressure output end (2c) and the first fixed reference end (2d), and is aligned with the first positioning groove (2h) provided on the side of the pressure output end (2c) and the first fixed reference end (2d). The connecting parts are connected by two symmetrical tuning fork arms (3d), and a slit (3c) is left between the two tuning fork arms. Electrodes are provided around the surface of the two tuning fork arms (3d), and the electrodes are electrically connected to each other for the tuning fork arms (3d) to start oscillating. Under the action of the inverse piezoelectric effect, when an alternating voltage is applied, the tuning fork arms (3d) are in a preset vibration mode. A detection electrode is provided on the upper surface of the connecting part (3a) at one end, and a solder pad connected to an external circuit is provided on the upper surface of the connecting part (3b) at the other end. The solder pad is connected to the PCB board through a gold wire.

7. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The diaphragm support structure (1c) and the pressure probe housing support structure (1e) are arranged in a coaxial annular shape.

8. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The first fixed reference end (2d) and the second fixed reference end (2e) are arranged symmetrically about the central axis of the pressure output end (2c); the surfaces of the pressure output end (2c), the first fixed reference end (2d) and the second fixed reference end (2e) are flush.

9. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The first quartz double-ended fixed vibration beam (3) and the second quartz double-ended fixed vibration beam (4) are located in the same plane and are mirror-symmetrically arranged; the first quartz double-ended fixed vibration beam (3) and the second quartz double-ended fixed vibration beam (4) have the same structure; when the first quartz double-ended fixed vibration beam (3) generates axial tensile stress under the action of displacement direction at the output end, the second quartz double-ended fixed vibration beam (4) generates axial compressive stress at the same time.

10. The quartz resonant pressure-sensitive structure according to claim 3, characterized in that: The metal pressure-sensitive diaphragm (1a) and the diaphragm support structure (1c) are integrated; the pressure transmission probe (1b) and the metal pressure-sensitive diaphragm (1a) are integrated; the diaphragm support structure (1c) and the pressure probe housing support structure (1e) are connected by welding or bonding; and the pressure transmission probe (1b) and the pressure input end (2a) are integrated by welding or bonding.

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