A press-in hole pressure sensor and a sensing method thereof by differential pressure measurement of an optical fiber

Abstract

The present application relates to a kind of press-in hole pressure sensor and its sensing method measured by optical fiber differential pressure, the sensor includes pressure sensing sensing part and detachably arranged on the pressure sensing sensing part optical fiber sensing part;Pressure sensing sensing part includes sensing part body and the pressure sensing head of being arranged at the sensing part body one end, the elastic clearance between the pressure sensing head and the sensing part body;Light source is arranged on the sensing part body, the light source is connected with light source switch, and light source is connected with optical fiber sensing part by optical fiber;Delay opening and closing structure is arranged between the pressure sensing head and the light source switch;By setting delay opening and closing structure, so that the sensor even after starting, even if environmental pressure value is suddenly reduced to below the value before starting also will not immediately hibernate, but will keep open state, to carry out more careful monitoring;Only when environmental pressure is below the value before starting, and distance certain difference will be converted into hibernate state.

Description

Technical Field

[0001] The invention relates to a pressure-in type pore pressure sensor for measuring pressure difference through optical fiber and a sensing method thereof. Background Art

[0002] The fiber-optic pressure differential-based pressure sensor is a sensor that converts the changes in the light signal (such as intensity, wavelength, phase, etc.) emitted by the light source into a measurable signal through optical fiber when an external physical quantity (such as pressure) acts on the modulation area.

[0003] Fiber Bragg Gratings (FBGs) or Fabry-Perot interferometers are typically used as sensing elements. When pressure acts on the sensor, the physical structure of the grating or interferometer cavity in the optical fiber changes, resulting in changes in the wavelength of the reflected light or the interference fringes.

[0004] The principle is that external pressure changes the period or refractive index of the fiber Bragg grating (FBG), thereby altering the wavelength of the reflected light. By detecting this change in wavelength, the magnitude of the pressure can be inferred. This system offers advantages such as electromagnetic interference resistance, corrosion resistance, high precision, and long-term stability.

[0005] The optical fiber differential pressure measurement is characterized by converting the wavelength change of the optical signal into a measurable, concrete digital value with high-precision digital representation.

[0006] It is often used to monitor pore water pressure in hydraulic structures, dams, tunnels and other projects. Due to its high-precision measurement of pore water pressure, it is widely used in civil engineering, geological monitoring and other fields.

[0007] Due to the requirements of its application scenarios, the sensor has an extremely long working cycle. Conventional press-fit pore pressure fiber optic sensors are online all year round, and their battery life and electronic components suffer from severe wear and tear, resulting in their lifespan being unable to meet the entire monitoring cycle.

[0008] Some sensors achieve normally closed status by setting a pre-start value, but the switching between the open and closed states is based on a specific pressure value. This means that when the pressure value fluctuates above and below the set pre-start value, the sensor will frequently switch between the open and closed states. In the long run, the failure rate will remain high. Summary of the Invention

[0009] The object of the present invention is to provide a pressure-insertion pore pressure sensor and a sensing method thereof for measuring differential pressure using optical fiber, so as to solve the problems raised in the above-mentioned background technology.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] A pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber comprises a pressure-sensitive sensing element and an optical fiber sensing element detachably arranged on the pressure-sensitive sensing element;

[0012] The pressure-sensitive induction element comprises an induction element body and a pressure-sensitive head arranged at one end of the induction element body, and an elastic clearance is provided between the pressure-sensitive head and the induction element body;

[0013] The sensing element body is provided with a light source, the light source is connected to a light source switch, and the light source is connected to the optical fiber sensing element via an optical fiber;

[0014] A delayed opening and closing structure is provided between the pressure sensing head and the light source switch;

[0015] The delayed opening and closing structure controls the light source to be energized through the light source switch when the pressure sensing head approaches the sensing element body until the elastic clearance between the two is completely eliminated;

[0016] In addition, when the pressure sensing head moves away from the sensing element body and the elastic clearance between the two is restored, the timing of turning off the light source by the light source switch is delayed.

[0017] The above-mentioned pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber: an internal sleeve is installed in the sensing element body, one end of the pressure sensing head extends into the internal sleeve, and the other end protrudes from the internal sleeve as a contact portion;

[0018] A ring platform is formed on a section of the outer circumference of the pressure sensing head that extends into the built-in sleeve. The pressure sensing head and the built-in sleeve are elastically connected by a compression spring and are fixed to the sensor body by a flange cover.

[0019] The above-mentioned pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber: a mounting guide rib is integrally provided on the inner wall of the built-in sleeve along the axial direction, and a guide groove for slidingly cooperating with the mounting guide rib is provided on the annular platform.

[0020] The above-mentioned pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber: a switch mechanical arm is rotatably provided on the light source switch, and the delayed opening and closing structure includes a tension spring connecting the light source switch and the end of the switch mechanical arm;

[0021] When the switch mechanical arm is vertically downward, the tension spring reaches the maximum stretching amount and is in a balanced state, so that the light source switch is in a critical position of power on and off.

[0022] The above-mentioned pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber: the pressure sensing head protrudes from a portion of the outer periphery of the sensing member body and is rotatably connected to one end of the push-pull member, and the other end of the push-pull member is rotatably connected to the push ring;

[0023] An embedding hole is formed on the inner wall of the push ring, a ball is movably embedded in the embedding hole, and the push ring and the rotating sleeve are matched;

[0024] Among them, a mounting post is provided on the outer wall of the sensor body, the rotating sleeve is rotatably provided on the mounting post, and the push ring is fitted with the rotating sleeve; a spiral groove is formed on the outer wall of the rotating sleeve, and the ball is also rollingly fitted on the spiral groove.

[0025] As described above, the pressure-insertion pore pressure sensor for measuring differential pressure through optical fiber: the rotating sleeve is provided with two contact rods parallel to the rotating sleeve, a gap is provided between the two contact rods, and the contact rods cooperate with the switch mechanical arm.

[0026] The above-mentioned pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber: the optical fiber sensing element is mounted on a hoop structure, and the hoop structure is connected to the sensing element body;

[0027] The hoop structure includes two semi-annular first and second hoops, the first and second hoops are hinged, and a mounting arm is formed at one end of the second hoop;

[0028] The optical fiber sensing component is mounted on the mounting arm.

[0029] As described above, the pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber: one end of the optical fiber sensing element is fixedly connected to the clamp, which cooperates with the through hole formed at the end of the mounting arm and is installed by bolts.

[0030] As described above, the pressure-insertion pore pressure sensor for measuring differential pressure through optical fiber: a screw is rotatably provided on one side of the mounting arm, a screw sleeve is threadedly connected to the screw, one side of the screw sleeve is rotatably connected to one end of a connecting rod, and the other end of the connecting rod is rotatably connected to the outer wall of the first hoop.

[0031] A method for sensing pore pressure using a pressure-inserted pore pressure sensor using optical fiber differential pressure measurement comprises the following steps:

[0032] Step 1: Pre-adjust the pre-start value, determine the maximum value of micro-vibration according to the on-site conditions of the measured environment, and select a compression spring with a matching elastic modulus;

[0033] Step 2: Assemble the sensor by sequentially installing the compression spring, built-in sleeve, and pressure sensing head into the sensor body and firmly connecting them to the sensor body through the flange cover; then, install the optical fiber sensor on the outer wall of the sensor body through the hoop structure; finally, connect the light source and the optical fiber sensor through the optical fiber;

[0034] Step 3: Fixed-point arrangement: Place the assembled sensors at the measured locations according to the calibrated monitoring points to detect the working status of the pressure-sensitive sensing components and the optical fiber sensing components when powered on;

[0035] Step 4: Bus connection: Connect the other end of the optical fiber sensor to the data receiving end through optical fiber to ensure that the sensor at each point can communicate normally with the data receiving end, and then connect the data receiving end to the sensing station;

[0036] Step 5: Data collection and recording: monitor the pressure values ​​sent and received by the data receiving end in real time at the sensing station, and record the data trend, continuity, peak and trough values.

[0037] Compared with the prior art, the present invention has the following advantages: an elastic clearance is provided between the pressure sensing head and the sensing element body, thereby modulating the pre-start value of the entire sensor; for example, a specific pre-start value can be preset, and when the pre-start value is not reached, the sensor remains in a normally closed state to filter out conventional micro-vibrations;

[0038] In the present invention, an elastic clearance is provided between the pressure sensing head and the sensing element body, so that conventional micro-vibration is not sufficient to activate the sensor, and the sensor is kept in a dormant state as much as possible to increase its endurance.

[0039] The present invention provides a delayed opening and closing structure, so that even after the sensor is started, even if the ambient pressure value drops sharply below the value before starting, it will not immediately go into sleep mode, but will remain in the open state for more thorough monitoring; it will only go into sleep mode when the ambient pressure is lower than the value before starting and the difference is a certain value. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Schematic diagram of the structure of a pressure-insertion pore pressure sensor that measures differential pressure through optical fiber.

[0041] Figure 2 This is a schematic diagram of the structure of another orientation of the pressure-insertion pore pressure sensor that measures pressure difference through optical fiber.

[0042] Figure 3 This is a schematic diagram of the structure of the pressure-sensing component in a pressure-insertion pore pressure sensor that measures differential pressure via optical fiber.

[0043] Figure 4 This is a schematic diagram of the partially disassembled structure of the pressure-sensitive sensor.

[0044] Figure 5 for Figure 4 Schematic diagram of another direction.

[0045] Figure 6 for Figure 5 Enlarged view of point A in the middle.

[0046] Figure 7 This is a schematic diagram of the structure of the pressure-sensitive head of the pressure-insertion pore pressure sensor that measures differential pressure through optical fiber.

[0047] Figure 8 for Figure 7 Enlarged view of point B in the middle.

[0048] Figure 9 For Figure 7 Schematic diagram of the disassembly of the rotating sleeve, push ring, and ball.

[0049] Figure 10 for Figure 9 Enlarged view of point C in the middle.

[0050] Figure 11 This is a schematic diagram of the disassembled rotating sleeve, push ring, and ball structure.

[0051] Figure 12 This is another structural diagram of the pressure-insertion pore pressure sensor that measures differential pressure through optical fiber.

[0052] Figure 13 for Figure 12 Enlarged view of point D in the middle.

[0053] Figure 14 This is a schematic diagram of the structure after the optical fiber sensing component and the clamp are removed from the mounting arm.

[0054] In the figure: 1-pressure sensing element; 101-pressure sensing head; 1011-ring platform; 1012-guide groove; 102-built-in sleeve; 1021-installation guide edge; 103-compression spring; 104-flange cover; 105-light source switch; 1051-switch mechanical arm; 106-mounting column; 107-rotating sleeve; 1071-touch rod; 1072-spiral groove; 108-push ring; 1081-embedded hole; 109-ball; 110-tension spring; 2-fiber optic sensing element; 201-light source; 202-clamp; 203-installation arm; 204-first hoop; 205-second hoop; 206-screw; 207-screw sleeve; 208-connecting rod; 3-push-pull element. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0056] See also Figures 1 to 14 As an embodiment of the present invention, the pressure-insertion pore pressure sensor for measuring differential pressure by optical fiber comprises a pressure-sensitive sensing element 1 and an optical fiber sensing element 2 detachably disposed on the pressure-sensitive sensing element 1;

[0057] The pressure sensing element 1 includes a sensing element body and a pressure sensing head 101 provided at one end of the sensing element body, and an elastic clearance is provided between the pressure sensing head 101 and the sensing element body;

[0058] The sensor body is provided with a light source 201, which is connected to the light source switch 105 and is connected to the optical fiber sensor 2 via an optical fiber.

[0059] A delayed opening and closing structure is provided between the pressure sensing head 101 and the light source switch 105;

[0060] The delayed opening and closing structure controls the light source 201 to be energized through the light source switch 105 when the pressure sensing head 101 approaches the sensing element body until the elastic clearance between the two is completely eliminated;

[0061] In addition, when the pressure sensing head 101 moves away from the sensing element body and the elastic clearance between the two is restored, the timing of turning off the light source 201 by the light source switch 105 is delayed.

[0062] In this embodiment, an elastic clearance is provided between the pressure sensing head 101 and the sensing element body to modulate the pre-start value of the entire sensor. For example, a specific pre-start value can be preset. When the pre-start value is not reached, the sensor remains in a normally closed state to filter out conventional micro-vibrations.

[0063] Conventional microvibrations are usually periodic or quasi-periodic, with clear time patterns and frequency characteristics, such as simple harmonic vibrations and forced vibrations. Conventional microvibrations are also usually continuous and stable, and the vibration process can last for a long time, such as the steady-state vibration of construction machinery systems.

[0064] In the present invention, an elastic clearance is provided between the pressure sensing head 101 and the sensing element body, so that conventional micro-vibration is not sufficient to activate the sensor, and the sensor is kept in a dormant state as much as possible to increase its endurance.

[0065] If macro vibrations occur, the pressure value will exceed the value before the sensor is activated, and the sensor will switch from sleep mode to active mode. Macro vibrations have large amplitudes, usually at the millimeter level or higher, and have a direct impact on structural stability. Macro vibrations are often non-periodic and have no clear pattern. They may be random or transient. Examples include ground vibrations caused by earthquakes and shock waves from explosions.

[0066] The present invention provides a delayed opening and closing structure, so that even after the sensor is started, even if the ambient pressure value drops sharply below the value before starting, it will not immediately go into sleep mode, but will remain in the open state for more thorough monitoring; it will only go into sleep mode when the ambient pressure is lower than the value before starting and the difference is a certain value.

[0067] As a further solution of the present invention, a built-in sleeve 102 is installed in the body of the sensing element, one end of the pressure sensing head 101 extends into the built-in sleeve 102, and the other end protrudes from the built-in sleeve 102 as a contact portion;

[0068] A ring platform 1011 is formed on a section of the outer circumference of the pressure sensing head 101 that extends into the built-in sleeve 102. The pressure sensing head 101 and the built-in sleeve 102 are elastically connected by a compression spring 103 and fixed to the sensor body by a flange cover 104.

[0069] It should be noted that the pressure sensing head 101 in the present invention is a split structure, including an external section and a buried section, and the buried section is a section extending into the built-in sleeve 102; when assembling the split structure, first insert the flange cover 104 into the buried section and then fix the external section and the buried section together.

[0070] When the flange cover 104 is fixed on the sensing part body, the compression spring 103 is pre-stressed, which will give the pressure sensing head 101 a force away from the sensing part body. However, since the ring platform 1011 is blocked by the flange cover 104, the compression spring 103 can be kept under pressure all the time, that is, a certain elastic clearance is achieved between the pressure sensing head 101 and the built-in sleeve 102 through the compression spring 103.

[0071] As a further solution of the present invention, in order to avoid relative rotation between the pressure sensing head 101 and the built-in sleeve 102, a mounting guide rib 1021 is integrally provided on the inner wall of the built-in sleeve 102 along the axial direction, and a guide groove 1012 for slidingly fitting with the mounting guide rib 1021 is provided on the ring platform 1011.

[0072] In this embodiment, since the built-in sleeve 102 has been fixed to the sensing part body through the flange cover 104, the built-in sleeve 102 cannot rotate; and with the help of the provided installation guide ribs 1021 and the guide grooves 1012, the pressure sensing head 101 cannot rotate either, and can only extend and retract relative to the built-in sleeve 102.

[0073] As a further solution of the present invention, a switch mechanical arm 1051 is rotatably provided on the light source switch 105, and the delayed opening and closing structure includes a tension spring 110 connecting the light source switch 105 and the end of the switch mechanical arm 1051;

[0074] When the switch mechanical arm 1051 is vertically downward, the tension spring 110 reaches the maximum stretching amount and is in a balanced state, so that the light source switch 105 is in a critical position of power on and off.

[0075] In this embodiment, when the pressure sensing head 101 is subjected to pressure and the pressure is less than the value before activation, the switch mechanical arm 1051 rotates but does not reach the equilibrium position, so the light source switch 105 will not be turned on.

[0076] When the pressure on the pressure sensing head 101 rises suddenly and exceeds the value before activation, as long as the pressure slightly exceeds the previous value, that is, the switch arm 1051 slightly exceeds the critical position, the switch arm 1051 will move quickly to energize the light source 201.

[0077] In the process of the pressure on the pressure-sensing head 101 decreasing, the switch arm 1051 will be closed only when it is reversed to the reverse direction and slightly exceeds the equilibrium position.

[0078] As a further solution of the present invention, the pressure sensing head 101 protrudes from a section of the outer periphery of the sensing element body and is rotatably connected to one end of the push-pull element 3, and the other end of the push-pull element 3 is rotatably connected to the push ring 108;

[0079] An embedding hole 1081 is formed on the inner wall of the push ring 108, and a ball 109 is movably embedded in the embedding hole 1081, and the push ring 108 is matched with the rotating sleeve 107;

[0080] Among them, a mounting column 106 is provided on the outer wall of the sensor body, the rotating sleeve 107 is rotatably provided on the mounting column 106, and the push ring 108 is fitted with the rotating sleeve 107; a spiral groove 1072 is formed on the outer wall of the rotating sleeve 107, and the ball 109 is also rollingly embedded in the spiral groove 1072.

[0081] In this embodiment, when the pressure sensing head 101 is subjected to pressure and the pressure is greater than the pre-pressure of the compression spring 103, the pressure sensing head 101 will shrink into the built-in sleeve 102. During the shrinkage of the pressure sensing head 101, the push ring 108 is driven away from the sensing element body by the push-pull member 3.

[0082] During this process, the push ring 108 drives the ball 109 away from the sensing element body, and the ball 109 cooperates with the spiral groove 1072 to drive the rotating sleeve 107 to rotate.

[0083] As a further solution of the present invention, two touch rods 1071 parallel to the rotating sleeve 107 are provided on the rotating sleeve 107 , a gap is provided between the two touch rods 1071 , and the touch rods 1071 cooperate with the switch mechanical arm 1051 .

[0084] In this embodiment, precisely because there is a gap between the two touch rods 1071, when the touch rod 1071 on one side drives the switch mechanical arm 1051 to cross the equilibrium position, if the pressure is reduced, the touch rod 1071 on the other side will not immediately drive the switch mechanical arm 1051 to reverse quickly. Instead, the gap between the touch rod 1071 on the other side and the switch mechanical arm 1051 needs to be eliminated before the touch rod 1071 on the other side reverses to drive the switch mechanical arm 1051 to reverse. When the touch rod 1071 on the other side drives the switch mechanical arm 1051 to reverse to the equilibrium position, it will continue to reverse to cut off the power to the light source 201 through the light source switch 105.

[0085] As a further solution of the present invention, the optical fiber sensing element 2 is mounted on a hoop structure, and the hoop structure is connected to the sensing element body;

[0086] The hoop structure includes two semi-annular first hoops 204 and second hoops 205, the first hoop 204 and the second hoop 205 are hinged, and a mounting arm 203 is formed at one end of the second hoop 205;

[0087] The optical fiber sensing component 2 is mounted on the mounting arm 203 .

[0088] In this embodiment, the two hinged ring hoops are used to make the entire ring hoop structure have the function of being openable and closable, which facilitates fixing the entire ring hoop structure and the mounting arm 203 on the outer wall of the sensor body.

[0089] As a further solution of the present invention, one end of the optical fiber sensing element 2 is fixedly connected to the clamp 202, and the clamp 202 cooperates with the through hole formed at the end of the mounting arm 203 and is installed by bolts.

[0090] In this embodiment, the provided clamp 202 is used to realize a detachable connection between the optical fiber sensing component 2 and the mounting arm 203 .

[0091] As a further solution of the present invention, a screw 206 is rotatably provided on one side of the mounting arm 203, and a screw sleeve 207 is threadedly connected to the screw 206. One side of the screw sleeve 207 is rotatably connected to one end of a connecting rod 208, and the other end of the connecting rod 208 is rotatably connected to the outer wall of the first hoop 204.

[0092] In this embodiment, the screw rod 206 is rotated to drive the screw sleeve 207 to move along the length direction of the screw rod 206 , and then the connecting rod 208 is used to control the opening and closing of the hinged first hoop 204 and the second hoop 205 .

[0093] In addition, the present invention also proposes a method for sensing by using the above-mentioned pressure-inserted pore pressure sensor for optical fiber pressure differential measurement, comprising the following steps:

[0094] Step 1: pre-adjust the pre-start value, determine the maximum value of micro-vibration according to the on-site conditions of the measured environment (including the vibration of construction machinery, the vibration of road vehicles with loads, and other factors), and select a compression spring 103 with a matching elastic modulus;

[0095] Step 2: Assemble the sensor. Install the compression spring 103, built-in sleeve 102, and pressure sensing head 101 into the sensor body in sequence and securely connect them to the sensor body via the flange cover 104. Then, install the optical fiber sensor 2 on the outer wall of the sensor body via a hoop structure. Finally, connect the light source 201 and the optical fiber sensor 2 via an optical fiber.

[0096] Step 3: Fixed-point arrangement: Place the assembled sensors at the measured locations according to the calibrated monitoring points to detect the working status of the pressure sensing element 1 and the optical fiber sensing element 2 when powered on;

[0097] Step 4: Bus connection: Connect the other end of the optical fiber sensing element 2 to the data receiving end through optical fiber to ensure that the sensor at each point can communicate normally with the data receiving end, and then connect the data receiving end to the sensing station;

[0098] Step 5: Data collection and recording: monitor the pressure values ​​sent and received by the data receiving end in real time at the sensing station, and record the data trend, continuity, peak and trough values.

[0099] The above embodiments are exemplary rather than restrictive, so any technical solution that can be implemented in other specific forms without departing from the spirit or basic features of the present invention is included in the present invention.

Claims

1. A pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber, comprising a pressure-sensitive sensing element (1) and an optical fiber sensing element (2) detachably arranged on the pressure-sensitive sensing element (1), characterized in that: The pressure-sensing element (1) comprises an induction element body and a pressure-sensing head (101) arranged at one end of the induction element body, and an elastic clearance is provided between the pressure-sensing head (101) and the induction element body; A light source (201) is provided on the sensing element body, the light source (201) is connected to the light source switch (105), and the light source (201) is connected to the optical fiber sensing element (2) via an optical fiber; A delayed opening and closing structure is provided between the pressure sensing head (101) and the light source switch (105); The delayed opening and closing structure controls the light source (201) to be energized via the light source switch (105) when the pressure sensing head (101) approaches the sensing element body until the elastic clearance between the two is completely eliminated; and delaying the timing of the light source switch (105) disconnecting the light source (201) during the process of the pressure sensing head (101) moving away from the sensing element body and restoring the elastic clearance between the two; A switch mechanical arm (1051) is rotatably provided on the light source switch (105), and the delayed opening and closing structure comprises a tension spring (110) connecting the light source switch (105) and an end of the switch mechanical arm (1051); When the switch mechanical arm (1051) is vertically downward, the tension spring (110) reaches its maximum stretching amount and is in a balanced state, so that the light source switch (105) is in a critical position for power on and off, and will only be closed when the switch mechanical arm (1051) is reversed to a reverse direction and slightly exceeds the balanced position.

2. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 1, characterized in that: A built-in sleeve (102) is installed in the body of the sensing element, one end of the pressure sensing head (101) extends into the built-in sleeve (102), and the other end protrudes from the built-in sleeve (102) to serve as a contact portion; A ring platform (1011) is formed on a section of the outer periphery of the pressure sensing head (101) extending into the built-in sleeve (102). The pressure sensing head (101) and the built-in sleeve (102) are elastically connected via a compression spring (103) and are fixed to the sensing element body via a flange cover (104).

3. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 2, characterized in that: A mounting guide rib (1021) is integrally provided on the inner wall of the built-in sleeve (102) along the axial direction, and a guide groove (1012) for slidingly engaging with the mounting guide rib (1021) is provided on the annular platform (1011).

4. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 1, characterized in that: The pressure sensing head (101) protrudes from a section of the outer periphery of the sensing member body and is rotatably connected to one end of the push-pull member (3), and the other end of the push-pull member (3) is rotatably connected to the push ring (108); An embedded hole (1081) is formed on the inner wall of the push ring (108), a ball (109) is movably embedded in the embedded hole (1081), and the push ring (108) and the rotating sleeve (107) are matched; A mounting post (106) is provided on the outer wall of the induction component body, the rotating sleeve (107) is rotatably provided on the mounting post (106), and the push ring (108) is fitted with the rotating sleeve (107); a spiral groove (1072) is formed on the outer wall of the rotating sleeve (107), and the ball (109) is also rollingly fitted in the spiral groove (1072).

5. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 4, characterized in that: Two touch rods (1071) parallel to the rotating sleeve (107) are provided on the rotating sleeve (107), a gap is provided between the two touch rods (1071), and the touch rods (1071) cooperate with the switch mechanical arm (1051).

6. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 2, characterized in that: The optical fiber sensing element (2) is mounted on a hoop structure, and the hoop structure is connected to the sensing element body; The hoop structure comprises two semi-annular first hoops (204) and a second hoops (205), the first hoops (204) and the second hoops (205) being hinged, and a mounting arm (203) is formed at one end of the second hoops (205); The optical fiber sensing component (2) is mounted on the mounting arm (203).

7. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 6, characterized in that: One end of the optical fiber sensing component (2) is fixedly connected to the clamp (202), and the clamp (202) matches a through hole formed at the end of the mounting arm (203) and is mounted by means of bolts.

8. The pressure-insertion pore pressure sensor for measuring differential pressure using optical fiber according to claim 6, characterized in that: A screw rod (206) is rotatably provided on one side of the mounting arm (203), a screw sleeve (207) is threadedly connected to the screw rod (206), one side of the screw sleeve (207) is rotatably connected to one end of a connecting rod (208), and the other end of the connecting rod (208) is rotatably connected to the outer wall of the first hoop (204).

9. A sensing method for a pressure-insertion pore pressure sensor using optical fiber pressure differential measurement as claimed in claim 6, characterized in that: The steps include: Step 1: pre-adjust the pre-start value, determine the maximum value of the micro-vibration according to the on-site conditions of the measured environment, and select a compression spring (103) with a matching elastic modulus; Step 2: Assemble the sensor, sequentially install the compression spring (103), the built-in sleeve (102), and the pressure sensing head (101) into the sensing body and firmly connect them to the sensing body through the flange cover (104); then install the optical fiber sensing element (2) on the outer wall of the sensing body through the hoop structure, and finally connect the light source (201) and the optical fiber sensing element (2) through the optical fiber; Step 3: Fixed-point arrangement: the assembled sensor is placed at the measured position according to the calibrated monitoring point, and the working state of the pressure sensing element (1) and the optical fiber sensing element (2) is detected when the power is on; Step 4: Bus connection: connect the other end of the optical fiber sensing element (2) to the data receiving end through the optical fiber to ensure that the sensor at each point can communicate normally with the data receiving end, and then connect the data receiving end to the sensing station; Step 5: Data collection and recording: monitor the pressure values ​​sent and received by the data receiving end in real time at the sensing station, and record the data trend, continuity, peak and trough values.

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