A pin coupling centrifugal check valve with monitoring function

Abstract

The present application belongs to the technical field of check valves, and particularly relates to a pin coupling centrifugal check valve with a monitoring function. The pin coupling centrifugal check valve comprises a check valve body, a support column and a fixed part. The check valve body is internally provided with a pin and a centrifugal block. The pin is movable under the action of centrifugal force to realize the check function. The check valve body is installed on the fixed part through the support column. In particular, the pin coupling centrifugal check valve further comprises an accelerometer. The top of the support column is provided with a groove, and the accelerometer is arranged in the groove. The accelerometer is embedded in the groove at the top of the support column, so that it is more closely coupled with the check valve body in structure, and can more directly perceive the slight vibration and impact signals generated by the check valve during operation. Compared with the surface mounting structure, the arrangement in the groove not only can reduce external interference and environmental pollution, but also is conducive to realizing stable installation and packaging protection, so as to improve the monitoring accuracy and the reliability of long-term operation.

Description

Technical Field

[0001] This invention belongs to the field of check valve technology, specifically relating to a centrifugal check valve with a pin coupling and monitoring function. Background Technology

[0002] A centrifugal backstop with a pin coupling is a safety component commonly used to prevent the reverse rotation of rotating mechanisms. It is widely used in the transmission systems of belt conveyors, bucket elevators, electric drums, and other equipment, and is particularly suitable for material transport and lifting applications in industries such as industry, mining, metallurgy, and ports. This type of backstop is typically installed between the motor or reducer and the load to prevent the transmission system from rotating in the opposite direction due to gravity when the equipment stops or loses power.

[0003] The pin-coupled centrifugal check valve mainly consists of a check valve body, a centrifugal block, a pin, a spring assembly, and an internal gear ring. Its working principle is as follows: When the equipment is running normally, the centrifugal block, under the action of centrifugal force, drives the pin to disengage from the internal gear ring, achieving an idling state; once the system reverses, the centrifugal force decreases or disappears, and the pin, under the action of the spring, engages with the internal gear ring, achieving check locking and preventing the equipment from reversing. The pin-coupled centrifugal check valve has advantages such as compact structure, rapid response, adaptability to high-speed rotation and repeated start-stop conditions, and easy installation.

[0004] However, because the pin-coupled centrifugal backstop operates under high load, high impact, and high-frequency start-stop conditions, it is prone to issues such as pin wear and jamming, loosening or breakage of the centrifugal blocks, and abnormal internal vibration. If these conditions are not detected in time, they will gradually develop into serious mechanical failures. Once the backstop fails, the equipment may rapidly reverse due to inertia or load gravity, causing damage to the conveying system and potentially leading to safety accidents such as the conveyed material falling back, chain breakage, and bearing seizure. Therefore, the health status of the backstop during its service life urgently needs to be monitored.

[0005] Currently, existing centrifugal backstops with pin couplings generally lack built-in monitoring devices, making it impossible to obtain their operating status in real time, identify potential faults, or provide early warnings of abnormal vibrations. Maintenance typically relies on periodic manual shutdowns for inspection, which suffers from slow response, high costs, and an inability to provide real-time control. Therefore, there is an urgent need for a centrifugal backstop with pin couplings that can monitor the vibration characteristics and operating status of the internal structure in real time without affecting the original structural performance, determining whether the backstop is in a worn, loose, or faulty state, thereby improving safety and reliability. Summary of the Invention

[0006] To address the above problems, the present invention provides a centrifugal check valve with a monitoring function, comprising a check valve body, a support column, and a fixing part; the check valve body contains a pin and a centrifugal block, the pin can move under centrifugal force to achieve the backstop function, and the check valve body is mounted on the fixing part via the support column; in particular, it also includes an accelerometer, the top of the support column is provided with a groove, and the accelerometer is disposed in the groove.

[0007] This invention achieves monitoring of the operating status of a pin-coupled centrifugal check valve by setting a groove at the top of the support column and embedding an accelerometer within the groove. Compared to mounting the accelerometer on the surface of the support column, the groove-embedded arrangement has higher mechanical coupling and signal response sensitivity, enabling it to more directly receive minute vibration or impact signals generated by structural abnormalities in the check valve body, such as loose pins or imbalance of the centrifugal blocks. The groove structure not only helps to stably fix the accelerometer, preventing it from being affected by external disturbances or environmental interference due to surface mounting, but also provides better encapsulation and protection, improving the reliability and long-term operational stability of the monitoring system, thereby solving the problem of existing check valves lacking real-time status sensing capabilities.

[0008] Furthermore, it also includes a packaging structure that covers the groove to protect the accelerometer. This not only prevents dust, oil, and moisture from entering, improving its environmental adaptability and service life, but also enhances the sensor's fixation stability, preventing loosening or displacement during operation, and helps improve the accuracy of vibration signal acquisition and the reliability of the monitoring system.

[0009] Furthermore, the accelerometer is a capacitive accelerometer, which has advantages such as simple structure, high sensitivity, and low power consumption. It is particularly suitable for monitoring minute and high-frequency vibration signals during the operation of the stop valve. The capacitive sensor can quickly respond to subtle displacement changes caused by early anomalies such as loose pins and unbalanced centrifugal blocks, enabling timely identification of fault conditions and improving the accuracy and reliability of the monitoring system.

[0010] Furthermore, the rectangular groove facilitates the placement of the accelerometer along the main vibration transmission direction from the backstop body to the support column, allowing for better alignment of its electrode structure with the vibration direction and thus enhancing the ability to detect abnormal signals from the backstop body. The rectangular groove also facilitates the placement of differential structure electrodes, expanding the effective sensing area, enhancing the response sensitivity to minute vibration displacements, and improving monitoring accuracy.

[0011] Furthermore, the capacitive accelerometer includes a movable electrode and a first fixed electrode. The two ends of the movable electrode are fixed on the opposite short sides of the groove, and the movable electrode is suspended. The first fixed electrode is fixed on the long side wall of the groove. The movable electrode and the first fixed electrode form a parallel plate capacitor structure, which is beneficial for the movable electrode to be displaced in a direction perpendicular to the fixed electrode when subjected to vibration, thereby changing the capacitance value, enhancing the sensitivity to the small vibrations of the backstop body, and improving the response speed and accuracy of fault monitoring.

[0012] Furthermore, it also includes a second fixed electrode, which is fixed to the other long sidewall of the groove. The first fixed electrode, the movable electrode, and the second fixed electrode constitute a differential structure. This structure has several advantages over a single-sided capacitor design. First, the differential structure can simultaneously sense the capacitance change of the movable electrode relative to the two fixed electrodes, forming two capacitance signals with opposite directions and similar amplitudes. When the movable electrode is vibrated and shifted, the capacitance on one side increases, while the capacitance on the other side decreases, thereby amplifying the detection signal and improving the sensitivity to small displacements. Second, the differential structure has good common-mode rejection capability, which can cancel common interference caused by temperature changes, power fluctuations, or thermal expansion and contraction of the overall structure, improving the system's anti-interference performance and output stability. In addition, this structure facilitates high-precision differential signal amplification and processing, making it suitable for accurate identification of abnormal states inside the check valve (such as slight pin jamming or centrifugal block eccentric impact) under complex vibration backgrounds. Therefore, the differential structure of this invention improves the robustness, sensitivity, and reliability of the monitoring system.

[0013] Furthermore, the long side of the groove closest to the backstop body bends inward. The capacitive accelerometer includes a movable electrode and a first fixed electrode. The first fixed electrode is attached to the curved sidewall of the groove, while the two ends of the movable electrode are fixed to the short side of the groove, making the movable electrode suspended. This structure has dual advantages: firstly, the curved sidewall can more concentratedly receive minute vibration signals from the backstop body, making the sensor's response to structural anomalies more direct and sensitive; secondly, a non-uniform electric field distribution is formed between the curved first fixed electrode and the straight, suspended movable electrode. When the movable electrode undergoes a minute displacement, it causes a non-linear enhancement in the capacitance change rate, meaning that under the same displacement conditions, a larger capacitance change is generated compared to the parallel plate structure, thereby improving the sensor's ability to detect subtle dynamic changes. This design enhances the ability to capture early fault characteristics of the backstop and improves the sensitivity and resolution of the monitoring system.

[0014] Furthermore, the capacitive accelerometer includes a movable electrode and a first fixed electrode, both of which are L-shaped. The two sides of the first fixed electrode are fixed to the adjacent long and short sidewalls of the groove. The movable electrode is fixed to the bottom surface of the groove by a flexible material, with its long side parallel to the long side of the first fixed electrode and its short side parallel to the short side of the first fixed electrode. This structural design allows the capacitive sensing surface to cover two mutually perpendicular directions, thus enabling simultaneous response to vibration signals from different directions. This is particularly suitable for multi-directional impacts or complex mechanical disturbances that may occur during the operation of the backstop. Through flexible connection, the movable electrode can generate relative displacement in multiple directions, forming multi-axial capacitance changes with the L-shaped fixed electrode, thereby improving the accelerometer's ability to capture multi-dimensional vibration characteristics and enhancing the comprehensive perception of abnormal states of the backstop.

[0015] Furthermore, the active electrode comprises a flexible material layer and a metal sputtering layer. This structure combines flexibility and conductivity, enabling the active electrode to maintain good electrical performance while possessing excellent mechanical deformability. The flexible material layer provides a large elastic deformation, allowing the electrode to undergo significant displacement when subjected to minor vibrations or accelerations, while the metal sputtering layer ensures stable capacitive response performance. Compared to traditional rigid electrodes, this structure is more prone to deformation with minor external vibrations, thereby enhancing the amplitude of capacitance changes and improving the sensor's sensitivity and detection accuracy in responding to early abnormal states of the backstop.

[0016] Furthermore, it also includes liquid metal, which is dropleted onto a sputtered metal layer. This invention utilizes the excellent conductivity and fluidity of liquid metal to further enhance the responsiveness of the active electrode to minute vibrations. When subjected to acceleration, the liquid metal can generate minute displacements or deformations on a flexible surface, thereby causing changes in the electric field distribution and effective capacitance area, enhancing the amplification effect on vibration signals. Its mobility allows the sensor to generate more significant capacitance changes even under low-frequency, small-amplitude vibration conditions, improving the sensing sensitivity to minor faults inside the check valve (such as early loosening, eccentric impact, etc.), further enhancing the dynamic response performance and detection resolution of the monitoring system.

[0017] The beneficial effects of this invention are:

[0018] (1) In this invention, the accelerometer is embedded in the groove at the top of the support column, so that it forms a tighter structural coupling with the backstop body, which can more directly sense the minute vibration and impact signals generated by the backstop during operation. Compared with the surface mount structure, the groove arrangement can not only reduce external interference and environmental pollution, but also facilitate stable installation and encapsulation protection, thereby improving the monitoring accuracy and long-term operational reliability.

[0019] (2) The capacitor structure designed in this invention makes the direction of the electric field consistent with the axial direction of the support column, that is, parallel to the main transmission path of the vibration of the backstop body. When an abnormality occurs inside the backstop (such as the pin being stuck or loose), its vibration signal is more easily transmitted to the capacitor area along the axial direction, thereby causing the moving electrode to produce a relative displacement and causing a change in capacitance, thus improving the sensor's response sensitivity and direction matching to key vibration signals.

[0020] (3) The present invention adopts a differential capacitor structure, that is, the movable electrode is placed between two fixed electrodes. When it is displaced by vibration, the capacitance on one side increases and the capacitance on the other side decreases, thereby amplifying the difference in capacitance change. This structure not only improves the detection resolution of small displacements, but also suppresses common-mode interference caused by temperature changes, power fluctuations, etc., so that the monitoring system maintains good stability and accuracy under complex working conditions.

[0021] (4) In this invention, the long side of the groove near the backstop body is designed to be bent inward, and a first fixed electrode is set on the bent side wall. This structure helps to concentrate and amplify the weak vibrations transmitted to the support column during the operation of the backstop, and at the same time forms a nonlinear electric field distribution between the electrodes, making the capacitance change when the moving electrode is displaced more significant, thereby improving the signal sensing capability and fault response effect.

[0022] (5) Both the active and fixed electrodes in this invention adopt an L-shaped design, with the electrode structure arranged along the long and short sides of the groove, so that the capacitive sensing direction covers two mutually perpendicular planes. This layout can simultaneously sense vibration signals from different directions, and is especially suitable for complex multi-directional impacts and disturbances generated during the operation of the backstop, thereby improving the multi-axis sensing capability and fault identification capability of the accelerometer.

[0023] (6) In this invention, liquid metal is dripped onto the surface of the active electrode, which utilizes its high conductivity and good mobility to further improve the capacitance response characteristics. When the backstop generates a slight vibration, the liquid metal undergoes local deformation or displacement on the surface of the flexible electrode, resulting in a more significant change in the effective capacitance area or electric field distribution. This helps to amplify changes in weak signals, thereby enhancing the sensitivity of early mechanical fault detection.

[0024] Based on the above beneficial effects, this invention has good application prospects in the field of backstop technology. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a centrifugal check valve with a pin coupling and monitoring function.

[0026] Figure 2 This is a schematic diagram of a capacitive accelerometer.

[0027] Figure 3This is a schematic diagram of another type of capacitive accelerometer.

[0028] Figure 4 This is a schematic diagram of another type of capacitive accelerometer.

[0029] Figure 5 This is a schematic diagram of another type of capacitive accelerometer.

[0030] In the figure: 1. Backstop body; 2. Support column; 3. Fixing part; 4. Accelerometer; 41. Movable electrode; 42. First fixed electrode; 43. Second fixed electrode. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments.

[0032] Example 1

[0033] This embodiment provides a centrifugal check valve with a pin coupling and monitoring function, such as... Figure 1 As shown, it includes a backstop body 1, a support column 2, a fixing part 3, and an accelerometer 4 installed in the support column 2, which is used to monitor and judge the abnormal state of the backstop in real time during operation.

[0034] The backstop body 1 adopts a conventional pin-coupling centrifugal structure, mainly comprising a housing, an internal gear ring, multiple pins, a spring assembly, a centrifugal block, a pin shaft, a support sleeve, and a rotating sleeve. The housing is a fixed structure used to support and restrict the installation position of all internal components. The internal gear ring is located inside the housing, with multiple toothed grooves evenly distributed along its circumference for engaging with the pins to achieve the backstop function. The rotating sleeve is coaxially mounted on the drive shaft and rotates in conjunction with the load side, serving as the active rotating unit of the entire backstop. Multiple pins are evenly arranged along the circumference of the rotating sleeve, with their front ends facing the internal gear ring and their rear ends connected to a spring assembly. This assembly pushes the pins towards the internal gear ring when there is no centrifugal force, causing them to engage in the toothed grooves. A guide pin hole is provided in the middle of each pin, through which the pin shaft passes and connects to the centrifugal block. The centrifugal block is located outside the pins, with one end hinged to the pin shaft and the other end extending freely. It can expand or contract radially using the centrifugal force during rotation. When the check valve is operating normally, i.e., the equipment is rotating in the forward direction, the rotating sleeve drives the pin and centrifugal block to rotate at high speed. At this time, centrifugal force acts on the centrifugal block, causing it to open outward and pull the pin outward through the pin shaft, moving it away from the inner gear ring, thus creating an idle state. The check valve does not engage in the transmission system. When the equipment stops rotating, the forward speed decreases, or the load tends to reverse, the rotation speed slows down, the centrifugal force weakens, and the centrifugal block retracts under the action of spring force, driving the pin to move radially inward and push into the tooth groove of the inner gear ring. At this time, the pin is embedded in the inner gear ring, forming a mechanical limiting contact with the gear ring in the reverse direction, realizing rotation prevention, i.e., the check valve function engages, preventing the equipment from reversing due to gravity or inertia. The key to the entire pin-coupling centrifugal check valve is: controlling the position of the pin through the coordinated switching of centrifugal force and spring force, realizing the function of idle during forward rotation and locking during reverse rotation. Meanwhile, since the pins, springs, and centrifugal blocks are in a state of high-speed rotation and frequent switching for a long time, their wear, jamming, or failure will directly affect the performance of the check valve. Therefore, it is necessary to use a highly sensitive condition monitoring device for fault early warning.

[0035] The backstop body 1 is mounted and fixed to the bottom fixing part 3 via the support column 2, which bears the weight of the backstop body 1 and transmits the force during operation to the mounting base. The support column 2 is preferably an integral metal column, which can be a solid structure or, as needed, has grooves or through holes in localized areas for functional integration. To ensure mechanical strength and fatigue resistance, the support column 2 is made of 40Cr alloy structural steel, which, after tempering heat treatment, possesses excellent comprehensive mechanical properties and processing adaptability. A rectangular groove is provided at the top of the support column 2 near the backstop body 1 for embedding a capacitive accelerometer. This groove can be machined at the upper end of the support column 2 using CNC milling or other methods. The depth and width are preset according to the accelerometer size, ensuring installation space while avoiding weakening the overall rigidity of the support column. By creating a groove in the top of the solid support column 2, the overall rigidity and stability of the column are ensured, and a reliable mounting point for the sensor is provided, facilitating structural integration and efficient signal coupling. The groove is positioned close to the backstop body 1, which allows the accelerometer 4 to directly sense the minute vibration signals generated by the operation of the backstop body 1, enhancing the directness of the signal transmission path and helping to realize timely monitoring and identification of conditions such as loose backstop structure, pin impact, and abnormal vibration.

[0036] The accelerometer 4 is a capacitive structure, located in a rectangular groove at the top of the support column 2, used to sense minute vibration signals generated by the backstop body 1 during operation. Figure 2 As shown, the accelerometer 4 mainly includes a movable electrode 41 and a first fixed electrode 42, which together constitute a parallel plate capacitive sensing structure. The movable electrode 41 uses a flexible polyimide (PI) film as a substrate, preferably 20-50 μm thick. A 0.1-0.5 μm thick conductive metal layer is formed on its surface using physical vapor deposition (PVD) or magnetron sputtering. The metal material can be aluminum, gold, copper, or silver. This flexible composite structure ensures both good conductivity and a large elastic deformation range, making it suitable for detecting low-frequency, small-amplitude vibrations. The two ends of the movable electrode 41 are fixed to the opposite short sides of the groove using high-strength epoxy resin or micro-screws, leaving the middle suspended, allowing relative displacement under axial or radial micro-vibrations. The groove dimensions are preferably 15-25 mm in length, 5-10 mm in width, and 3-5 mm in depth, adjustable according to the specific sensor size. The length of the movable electrode 41 is slightly less than the groove length to ensure that the edge does not contact the groove wall, avoiding signal interference. The width of the active electrode 41 is generally 2-4 mm to balance the sensing area and dynamic response.

[0037] During the operation of the backstop, if the backstop body 1 experiences a slight impact due to pin wear, centrifugal block imbalance, or structural loosening, the movable electrode 41 will undergo a slight displacement under the action of flexible support, causing a change in the distance between it and the first fixed electrode 42, thereby causing a change in capacitance and outputting a dynamic response signal that can be detected by the signal processing unit.

[0038] The movable electrode 41 and the first fixed electrode 42 are each connected to a pre-set electrode lead-out hole at the bottom of the groove via two independent wires. This lead-out hole is located on both sides of the bottom surface of the groove near the short side, with a preferred diameter of 1.0-1.5 mm, large enough to accommodate a thin conductor with a diameter of 0.3-0.5 mm. The edges are chamfered to prevent cable wear and breakage. The electrodes are securely connected to the wires using silver paste or micro-soldering to ensure stable signal transmission and long-term operation without loosening. The electrode lead-out hole communicates with a small cable channel located inside the support column 2. This channel is a long, narrow passage extending along the axis of the support column, with a diameter of approximately 2-3 mm. It is formed by drilling or pre-drilling, and the path planning avoids sharp bends or weak points in the structure to ensure smooth wire laying without affecting the overall mechanical strength of the column. The wire is led down along this cable channel to a protective wiring cavity located at the bottom of the support column 2. The wiring cavity is a closed cavity opened at the bottom of support column 2, housing signal amplification, capacitance acquisition, or filtering components, and pre-installed with standard communication ports (such as RS485, CAN, or analog signal pins) for connection to external acquisition systems. To improve environmental adaptability, the entire lead-in channel is encapsulated with epoxy resin or modified silicone. After electrode connection, sealing material is injected from the lead-out holes to the bottom of the column, forming a continuous, dense, and flexible protective filler. This encapsulation structure provides dustproof, waterproof, oil-mist-proof, corrosion-resistant, and vibration-resistant properties, enabling long-term stable operation in high-humidity, dusty, or high-vibration industrial environments. It prevents wire detachment, poor contact, or signal drift, thereby ensuring the stability and reliability of the entire monitoring system.

[0039] The wiring cavity integrates a miniature differential capacitance acquisition module for real-time, high-precision detection of capacitance changes in the capacitive accelerometer. This acquisition module, composed of a precision capacitance detection chip (such as the ADI AD7746 or similar devices), supports differential mode access and can simultaneously acquire capacitance change signals between the moving electrode 41 and the first fixed electrode 42 and the second fixed electrode 43. It achieves sub-picofarad level capacitance change measurement with a resolution of up to 24 bits, exhibiting extremely high sensitivity and stability. The analog signal output from the acquisition module is converted into a digital signal via a built-in analog-to-digital converter (ADC) and transmitted in real-time to a miniature low-power processing chip (such as the STM32L series or TI MSP430 series) located in the same wiring cavity. This chip is dedicated to local data preprocessing and fault diagnosis, integrating various digital signal processing modules, including sliding window filtering, abrupt change threshold identification, frequency domain analysis (FFT), and adaptive data denoising algorithms. These algorithms filter out background vibration and resonance interference, improving the accuracy and timeliness of identifying abnormal states inside the stop valve (such as loose pins, centrifugal block eccentricity, internal impact, etc.). The processing chip packages the analysis results into data frames and supports real-time transmission to a host computer system, PLC, or remote monitoring platform via industrial standard communication interfaces such as CAN bus, RS485, or Modbus RTU protocol. The communication module has address recognition and multi-node link management capabilities, making it compatible with centralized vibration monitoring systems to achieve remote monitoring, trend analysis, early warning, and abnormal operating condition alarms for the stopcock. Furthermore, the system can be configured with alarm thresholds and self-diagnostic logic. Once the collected capacitance change exceeds the set limit, the processing chip can trigger local LED flashing, a buzzer alarm, or send an abnormal signal through the communication system to prompt maintenance personnel for timely repair.

[0040] To enhance the structural protection, an integrated encapsulation structure is incorporated outside the groove, its shape matching the groove and directly covering the groove opening. The encapsulation structure is made of high-temperature resistant, high-toughness epoxy resin, formed through in-situ curing after injection, and tightly bonded to the inner wall of the groove. This encapsulation layer structurally completely covers the entire accelerometer 4, preventing corrosion or contamination of the electrode structure by dust, oil mist, water vapor, and other complex environmental conditions, thus ensuring the stable operation of the accelerometer. This simple and compact structure is suitable for mass production and extends the sensor's service life in harsh environments.

[0041] Example 2

[0042] Based on Example 1, this example further introduces a differential structure to improve the monitoring sensitivity and anti-interference capability of the backstop body vibration state.

[0043] The accelerometer 4 is housed in a rectangular groove at the top of the support column 2, with a structure identical to that of Embodiment 1. The difference lies in... Figure 3 As shown, in addition to the first fixed electrode 42 located on the side of the groove near the backstop body 1, a second fixed electrode 43 is added on the long side wall on the opposite side. The first fixed electrode 42 and the second fixed electrode 43 are respectively led to the electrode lead-out hole at the bottom of the groove through wires, and further connected to the differential acquisition module located in the wiring cavity at the bottom of the support column 2. The first fixed electrode 42, the second fixed electrode 43 and the movable electrode 41 located in the middle form a symmetrically distributed differential capacitor structure.

[0044] The movable electrode 41 is still a composite of a flexible PI film and a metal sputtered layer, suspended in the middle of the groove, and can generate a small deformation in the vertical direction when the support column 2 is subjected to vibration. Since the movable electrode 41 is located between two symmetrically arranged fixed electrodes, even a small displacement will cause the two capacitors (C1, the capacitance between the movable electrode and the first fixed electrode 42; C2, the capacitance between the movable electrode and the second fixed electrode 43) to change by opposite magnitudes, thereby forming a difference signal ΔC = C1 - C2.

[0045] The wiring cavity integrates a high-sensitivity differential capacitance acquisition chip (such as Analog Devices' AD7747), which can simultaneously connect to two capacitance channels and monitor the differential change value ΔC in real time. Compared with single-ended capacitance acquisition, this structure can suppress common-mode interference such as temperature drift, power supply noise, and mechanical resonance, thereby improving the system's anti-interference capability and dynamic resolution.

[0046] The differential capacitance signal output from the acquisition module is converted from analog to digital by a 24-bit ADC and processed in real time by a microprocessor chip (such as STM32L452). The chip has preset differential signal dynamic compensation algorithm, threshold mutation judgment algorithm, FFT spectrum analysis module, data buffer and hierarchical alarm logic. The final processing result is sent to a remote industrial monitoring platform via CAN bus or RS485 serial port. The platform can display vibration trend graphs and historical change curves in real time, and supports automatic generation of maintenance suggestions or alarm information, realizing remote intelligent monitoring and fault early warning of the backstop's operating status.

[0047] The combination of this differential structure and the intelligent analysis system further improves the system's working stability and fault identification accuracy in high vibration and strong interference environments, making it particularly suitable for harsh operating environments of backstops such as mines, heavy-duty conveyors, and power plants.

[0048] Example 3

[0049] Based on Example 1, this example further optimizes the structural arrangement of the capacitive accelerometer in the groove. Specifically, it adopts a design of curved long sidewalls and attached fixed electrodes to improve the response capability to vibration signals transmitted from the direction of the backstop body 1 and enhance the amplitude of capacitance change.

[0050] like Figure 4 As shown, the top groove of the support column 2 is rectangular. The long side of the support column, which is close to the backstop body 1, is pre-processed and bent into the groove in an arc or zigzag shape to form a non-straight curved sidewall. This sidewall is integrally formed by CNC milling or internal casting. The bending radius is preferably 5-10mm to ensure sufficient installation area without affecting the overall strength of the support column.

[0051] The first fixed electrode 42 is made of flexible metal foil material (such as 0.05 mm thick copper foil or stainless steel sheet), which is attached to the inner surface of the curved sidewall and tightly bonded to the sidewall by conductive adhesive, solder joints or nano silver paste. Due to the curved shape of the sidewall, the first fixed electrode 42 will exhibit a non-linear unfolding surface, forming a non-parallel coupling structure with the movable electrode 41 in space with an expandable deformation.

[0052] The movable electrode 41 remains suspended and is composed of a flexible PI film and a metal sputtering layer, with both ends fixed above the short side of the groove. Because it forms a spatial angle-changing structure with the first fixed electrode 42, when the support column 2 experiences micro-vibration due to the backstop's operation (especially recoil or collision along the vertical axis), the movable electrode 41 will undergo slight deflection or deformation, resulting in a greater change in its effective capacitance distance relative to the first fixed electrode 42. This leads to a more significant capacitance change per unit vibration.

[0053] In this embodiment, the curved sidewall serves to focus the signal and guide the vibration, which can concentrate the vibration transmission in the direction of the backstop body 1 to the attached electrode area, thereby improving the sensitivity of local vibration sensing. The non-parallel structure makes the electric field distribution more sensitive, and the small displacement of the movable electrode 41 can cause a larger capacitance change, thereby enhancing the signal amplitude.

[0054] In summary, this embodiment improves the sensitivity and adaptability of the accelerometer 4 to abnormal conditions of the backstop by optimizing the electrode mounting interface and signal transmission path without changing the overall structure of the support column 2. It is particularly suitable for monitoring early damage and loosening faults caused by axial or eccentric impacts.

[0055] Preferably, a small, high-density material block, such as tungsten or platinum particles, is placed on top of the movable electrode 41 and firmly connected to the metal sputtering layer through physical bonding or micro-welding. Under the vibration of the support column 2, this high-density block can generate more significant micro-displacement due to its large inertial mass, thereby causing a greater deformation of the flexible movable electrode 41 and resulting in a significant change in capacitance. This design enhances the accelerometer's response sensitivity to minute vibrations or transient impacts, improving fault identification capabilities.

[0056] Example 4

[0057] Based on Embodiment 1, this embodiment further optimizes the structural design of the capacitive accelerometer. Both the active electrode 41 and the first fixed electrode 42 adopt an L-shaped configuration, with their edges arranged along the long and short sides of the groove, so that the capacitive sensing direction covers two mutually perpendicular planes, thereby realizing the synchronous sensing of multi-directional vibration signals.

[0058] The top of the support column 2 has a rectangular groove with dimensions of 10mm in length, 6mm in width, and 2.5mm in depth. The long side is parallel to the rotation axis of the backstop, and the short side is perpendicular to the axis. The groove is located near the backstop body 1, and the accelerometer 4 is housed within it. The movable electrode 41 is an L-shaped flexible structure with a 50μm thick polyimide film as the substrate. A 200nm thick metal sputtering layer is formed on its surface through physical vapor deposition, providing both flexibility and conductivity. The bottom of the movable electrode 41 is adhered to the bottom surface of the groove with flexible epoxy adhesive, its long side parallel to the long side of the groove, and its short side parallel to the short side of the groove.

[0059] The first fixed electrode 41 is also an L-shaped metal sheet structure, made of stainless steel with a thickness of approximately 0.1 mm. It is fixed to the inner wall of one long side and the inner wall of one adjacent short side of the groove by structural adhesive or welding. The overall shape is geometrically parallel to the movable electrode. The movable electrode 41 and the first fixed electrode 41 form two mutually perpendicular planar capacitive sensing areas.

[0060] During the operation of the backstop, the mechanical system may be subjected to dynamic interference from multiple directions, such as axial impact, radial disturbance, and rotational imbalance. Traditional unidirectional capacitor structures are unable to fully capture signals from all directions. However, by using an L-shaped electrode design, the sensing surface is distributed along two directions, enabling the system to simultaneously monitor minute vibrations from both the axial and radial directions, thus improving multi-axis response capability.

[0061] In summary, this embodiment achieves sensitive detection and differentiation of multi-directional vibrations by using an L-shaped electrode design within a limited space, making it particularly suitable for monitoring backstops with compact structures and complex vibration characteristics.

[0062] Example 5

[0063] Based on Examples 1-4, this example further optimizes the acceleration response performance. In particular, liquid metal microdroplets are dropped onto the surface of the metal sputtered layer of the active electrode 41 to enhance the sensor's response sensitivity to minute vibrations and the amplitude of nonlinear capacitance changes.

[0064] The movable electrode 41 is composed of a flexible polyimide film and a surface copper sputtered layer, and is strip-shaped or L-shaped (as can be combined with Embodiment 3 or Embodiment 4). The movable electrode 41 is fixed in a suspended state at both ends of the short side of the groove at the top of the support column 2, and the middle part vibrates freely.

[0065] In this embodiment, a droplet of liquid metal with a volume of approximately 1-2 μL is deposited onto the metal layer on the surface of the active electrode using a microneedle injector. Room temperature liquid metal gallium-based alloy is preferably used. The liquid metal is distributed in a spherical or flat droplet shape, allowing for good wetting and conductive adhesion to the sputtered metal layer.

[0066] Liquid metal has a high density (greater than or equal to 6.0 g / cm³). 3 After being dripped into the middle of the flexible electrode, the liquid metal is equivalent to introducing a mass block into the electrode, making it easier to deform under low-frequency micro-perturbations and improving the displacement response in the low vibration frequency range. In addition, the liquid metal undergoes its own shape change (elliptical, flowing) under micro-displacement, changing the electric field distribution. This means that the capacitance change not only comes from the spacing change, but also from the superimposed changes in effective area and dielectric path, increasing the signal amplitude. Furthermore, the liquid metal can flow back to its original position after deformation, possessing a certain degree of self-healing and stability, which is beneficial to extending the sensor's lifespan.

[0067] This embodiment integrates the mass response and deformation amplification characteristics of liquid metal, improving the detection capability of capacitive accelerometers for minute vibrations and impacts. It is especially suitable for capturing and warning of weak anomalies such as micro-cracks, jamming, and loosening in the early stages of backstop operation.

[0068] In summary, this invention provides a centrifugal check valve with a pin-coupling design and monitoring capabilities. Based on the traditional check valve structure, it innovatively incorporates a capacitive accelerometer at the top of the support column 2, embedding it within a groove and protecting it through encapsulation to adapt to complex operating conditions. This accelerometer features diverse structures, including differential structures, curved sidewall-enhanced coupling designs, L-shaped multi-directional sensing arrangements, and composite structures of flexible materials and liquid metal. This enhances the sensitivity and identification capability for various mechanical anomalies during check valve operation, such as wear, loosening, and impact. It possesses high integration, strong anti-interference capabilities, and remote online monitoring capabilities, providing technical support for the safe and reliable operation of the check valve.

[0069] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A pin coupling centrifugal type check valve with monitoring function, comprising a check valve body, a support column, a fixed part, wherein a pin and a centrifugal block are arranged in the check valve body, the pin is movable under the action of centrifugal force to realize the check function, and the check valve body is installed on the fixed part through the support column, characterized in that: The accelerometer is further included, the top of the support column is provided with a groove, the accelerometer is arranged in the groove, the groove is rectangular, the accelerometer is a capacitive accelerometer, the capacitive accelerometer comprises a movable electrode and a first fixed electrode, two ends of the movable electrode are fixed on opposite short sides of the groove, the movable electrode is in a suspended state, the first fixed electrode is fixed on a long side sidewall of the groove, and the movable electrode and the first fixed electrode form a parallel-plate capacitor structure. ​ 2. The pin coupling centrifugal check valve with monitoring function according to claim 1, characterized in that: The packaging structure is further included, and the packaging structure covers the groove.

3. The pin coupling centrifugal check valve with monitoring function according to claim 1, characterized in that: The second fixed electrode is further included, and the second fixed electrode is fixed on another long side sidewall of the groove.

4. The pin coupling centrifugal check valve with monitoring function according to claim 1, characterized in that: The first fixed electrode is attached to the curved sidewall of the groove, and two ends of the movable electrode are fixed on the short sides of the groove.

5. The pin coupling centrifugal check valve with monitoring function according to claim 1, characterized in that: The capacitive accelerometer comprises a movable electrode and a first fixed electrode, the movable electrode and the first fixed electrode are both L-shaped, two sides of the first fixed electrode are fixed on adjacent long side sidewalls and short side sidewalls of the groove, the movable electrode is fixed on the bottom surface of the groove through a flexible material, a long side of the movable electrode is parallel to a long side of the first fixed electrode, and a short side of the movable electrode is parallel to a short side of the first fixed electrode.

6. The pin coupling centrifugal check with monitoring function according to any of claims 3-5, characterized in that: The movable electrode comprises a flexible material layer and a metal sputtering layer.

7. The pin coupling centrifugal check valve with monitoring function according to claim 6, characterized in that: The liquid metal is further included, and the liquid metal is dropped on the metal sputtering layer.

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