A marine low-speed diesel engine propulsion system safety monitor

Abstract

The application discloses a marine low-speed diesel engine propulsion system safety monitoring instrument, and relates to the technical field of ship safety monitoring. The lower side of the outer wall of the base is provided with a positioning block one, the side of the diesel engine body close to the base is provided with a groove one, the groove one is matched with the positioning block one, the lower side of the outer wall of the positioning block one is provided with a mounting groove, the inside of the mounting groove is provided with a pressure sensor, the middle part of the outer wall of the base is provided with a mounting hole, the inside of the mounting hole is provided with a pre-tightening bolt, the inner wall of the base is provided with a shearing groove in the radial direction, and the inside of the shearing groove is provided with a buffer block in interference. The positioning block one, the groove one, the pre-tightening bolt, the pressure sensor, the acceleration sensor and the temperature sensor are installed, the function of stable information collection is realized, the base installation pre-tightening force can be maintained in the vibration working condition through the self-locking of the positioning block one and the groove one, and the equipment information collection accuracy and stability are improved.

Description

Technical Field

[0001] This invention relates to the field of ship safety monitoring technology, specifically to a safety monitoring instrument for a marine low-speed diesel engine propulsion system. Background Technology

[0002] Marine low-speed diesel engines are the core power units for ocean-going vessels, large container ships, oil tankers and bulk carriers. Their operational reliability is directly related to the safety of ship navigation, cargo transportation efficiency and marine environmental safety. As ships develop towards larger, more intelligent and unmanned directions, the ocean voyage cycle has been extended to more than 6 months. The unmanned engine room mode is gradually becoming more common, and the requirements for the reliability, maintainability and environmental adaptability of diesel engine safety monitoring instruments are gradually increasing.

[0003] Existing safety monitoring devices generally use flat-fit and ordinary bolt fixing installation methods. Under continuous vibration, the bolt preload will gradually decrease, which will cause the sensor installation to loosen or generate relative displacement, resulting in distorted measurement data, false alarms or missed alarms. In severe sea conditions, instantaneous impacts will further aggravate the sudden drop in preload, and may even cause the sensor to fall off and completely lose its monitoring function. In order to mitigate the impact of vibration, existing technologies mostly use rubber pads or spring vibration isolators as passive vibration isolation. Although the impact of vibration is reduced, it also leads to insufficient sensor installation strength, which cannot fully transmit diesel engine vibration, making it impossible for the safety monitoring device to identify early high-frequency vibration faults.

[0004] Patent CN117368606B discloses a method for monitoring and diagnosing faults in a ship's electric propulsion system. This patent improves the reliability and accuracy of fault diagnosis in the target ship's electric propulsion system to a certain extent. After ruling out faults in the target ship's load unit, it conducts emergency fault investigation and early warning for the target ship, and further provides maintenance personnel with more detailed directions for carrying out maintenance work.

[0005] The aforementioned patent monitors the current operating status parameters of the target vessel to grasp its operational status in real time. In case of abnormal operation, it promptly sends fault source location commands and sequentially diagnoses and troubleshoots the power generation unit, propulsion unit, and load unit of the target vessel. It scientifically and comprehensively understands the historical operation of the power generation unit, propulsion unit, and load unit of the target vessel, and analyzes the probability of operational failure of the power generation unit, propulsion unit, and load unit of the target vessel in the form of data. There is room for optimization in terms of vibration-induced sensor loosening and vibration transmission efficiency.

[0006] Therefore, this application proposes a safety monitoring device for marine low-speed diesel engine propulsion system that can stably collect information. Summary of the Invention

[0007] The purpose of this invention is to provide a safety monitoring device for marine low-speed diesel engine propulsion systems, in order to solve the technical problems mentioned in the background art, such as sensor loosening caused by vibration and decreased vibration transmission efficiency caused by isolated vibration damping.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a safety monitoring instrument for a marine low-speed diesel engine propulsion system, comprising a base and a diesel engine body, a positioning block being provided on the lower side of the outer wall of the base, a groove being provided on the side of the diesel engine body near the base, the groove being matched with the positioning block, an installation groove being provided on the lower side of the outer wall of the positioning block, a pressure sensor being provided inside the installation groove, an installation hole being provided through the middle of the outer wall of the base, a pre-tightening bolt being provided inside the installation hole, a shear groove being provided radially on the inner wall of the base, a buffer block being interference-fitted inside the shear groove, a temperature sensor being provided on the inner wall of the base near the shear groove, an acceleration sensor being provided on the front side of the outer wall of the base, and a controller being provided on the left side of the outer wall of the base, the pressure sensor, the temperature sensor, and the acceleration sensor being connected to the controller via signal lines.

[0009] Preferably, a mounting base is provided on the upper side of the outer wall of the base, a positioning block two is provided on the lower side of the inner wall of the mounting base, a vibration hole is provided through the lower side of the outer wall of the mounting base, and a socket is provided on the lower side of the inner wall of the mounting base. The socket is connected to the controller through a signal line.

[0010] Preferably, a monitoring box is provided on the upper side of the outer wall of the mounting base, and a second groove is provided on the lower side of the outer wall of the monitoring box. The second groove matches the second positioning block. A pin is provided on the lower side of the outer wall of the monitoring box. The pin cooperates with the socket. A sensitive element is provided inside the monitoring box. The sensitive element is connected to the pin through a signal line. A support base is provided circumferentially in the middle of the inner wall of the monitoring box. The sensitive element is connected to the support base through a traction rope. A damping plate is provided on the outer wall of the sensitive element. The two ends of the damping plate are respectively connected to the inner wall of the monitoring box and the outer wall of the sensitive element. The monitoring box is filled with silicone gel.

[0011] Preferably, a vibrator is provided in the middle of the inner wall of the base, the vibrator is rigidly connected to the lower side of the inner wall of the base, a vibration transmission rod is provided at the output end of the vibrator, the vibration transmission rod passes through the vibration hole and contacts the lower side of the outer wall of the monitoring box, and sealing rings are provided on both the upper and lower sides of the outer wall of the vibration hole, and the vibrator is connected to the controller through a signal line.

[0012] Preferably, a mounting bracket is provided on the upper side of the outer wall of the base, an adjusting motor is provided on the upper side of the outer wall of the mounting bracket, a reducer is provided on the lower side of the outer wall of the mounting bracket, the reducer is connected to the output end of the adjusting motor, a torque sensor is provided on the output end of the reducer, and a sleeve is connected to the output end of the reducer via a spline. The sleeve is engaged with a pre-tightening bolt. The adjusting motor, reducer, and torque sensor are respectively connected to the controller via signal lines.

[0013] Preferably, a washer is provided at the connection between the pre-tightening bolt and the base.

[0014] Preferably, there are 6 shear grooves, which are symmetrically distributed inside the base. The shear grooves are arc-shaped variable cross-section structures with a central angle of 25° to 30°. An exhaust hole is provided on the lower side of the inner wall of the shear groove, which extends to the outer wall of the base.

[0015] Preferably, the monitoring box has 4 sets of limiting posts on the lower side of its inner wall, the support base is symmetrically distributed in a star shape, and there are 6 sets of damping plates, which correspond to the positive and negative directions of the X, Y and Z axes of the sensitive element.

[0016] Preferably, the inner wall of the mounting base is provided with a locking hole, a locking ball is provided inside the locking hole, a locking spring is provided on the outer wall of the locking ball near the outer wall of the mounting base, a push rod is provided on the outer wall of the mounting base corresponding to the locking hole, the two ends of the locking spring are connected to the locking ball and the push rod respectively, and a locking groove is provided on the outer wall of the monitoring box, the locking groove matching the locking ball.

[0017] Preferably, both positioning block one and positioning block two are wedge-shaped, with wedge angles of 8° to 12°, and there are three positioning blocks of each type, distributed at 120°.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] 1. This invention, by installing a positioning block, a groove, a pre-tightening bolt, a pressure sensor, an acceleration sensor, and a temperature sensor, achieves stable information acquisition, solves the problems of sensor loosening, low vibration transmission efficiency, and measurement distortion, and can maintain the base installation pre-tightening force under vibration conditions through the self-locking of the positioning block and the groove, thereby improving the accuracy and stability of equipment information acquisition.

[0020] 2. This invention, by installing a monitoring box, achieves the function of eliminating vibration and shock, solving the problems of vibration and shock damaging equipment, severe attenuation of high-frequency vibration signals, and inconsistent three-dimensional measurement accuracy. It can avoid the main vibration frequency band of the diesel engine body, improve the shock resistance of the equipment, and improve the information acquisition accuracy of the equipment.

[0021] 3. This invention, by installing an acceleration sensor, a vibrator, a vibration transmission rod, and a locking hole, realizes the function of automatic calibration of sensitive elements, avoiding the problems of long calibration time, repeated calibration due to installation deviation, and large calibration error. It can quickly complete the calibration of sensitive elements, quickly complete the replacement of monitoring boxes, shorten equipment downtime, and enable uninterrupted monitoring of the diesel engine body.

[0022] 4. This invention, by installing pre-tightening bolts, adjusting motors, reducers, and torque sensors, achieves the function of automatic base locking, solving the problems of equipment failure, sudden drop in pre-tightening force, and delayed manual maintenance caused by loosening. It can automatically adjust the torque of the pre-tightening bolts, maintain the stability of the base pre-tightening force, prevent equipment loosening, and improve the accuracy of information collection. Attached Figure Description

[0023] Figure 1 This is a front view structural diagram of the present invention;

[0024] Figure 2 This is a schematic diagram of the base structure of the present invention;

[0025] Figure 3 This is a schematic diagram of the mounting base and monitoring box structure of the present invention;

[0026] Figure 4 This is a schematic diagram of the exciter and vibration transmission rod structure of the present invention;

[0027] Figure 5 This is a schematic diagram of the mounting bracket and pre-tightening bolt structure of the present invention;

[0028] Figure 6 This is a schematic diagram of the locking hole and push rod structure of the present invention;

[0029] Figure 7 This is a top view schematic diagram of the positioning block and shear groove of the present invention;

[0030] Figure 8 This is a top view of the monitoring box structure of the present invention.

[0031] In the diagram: 1. Base; 2. Diesel engine body; 3. Positioning block one; 4. Groove one; 5. Mounting groove; 6. Pressure sensor; 7. Mounting hole; 8. Preload bolt; 9. Shear groove; 10. Buffer block; 11. Acceleration sensor; 12. Temperature sensor; 13. Controller; 14. Mounting base; 15. Positioning block two; 16. Vibration hole; 17. Socket; 18. Monitoring box; 19. Groove two; 20. Pin; 21. Sensitive element; 22. Support base; 23. Traction rope; 24. Damping plate; 25. Vibrator; 26. Vibration transmission rod; 27. Sealing ring; 28. Mounting bracket; 29. ​​Adjusting motor; 30. Reducer; 31. Torque sensor; 32. Sleeve; 33. Washer; 34. Exhaust port; 35. Limiting post; 36. Locking hole; 37. Locking ball; 38. Locking spring; 39. Push rod; 40. Locking groove. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] Example 1: Please refer to Figure 1 , Figure 2 and Figure 7 A safety monitoring device for a marine low-speed diesel engine propulsion system includes a base 1 and a diesel engine body 2. A positioning block 3 is provided on the lower side of the outer wall of the base 1. A groove 4 is provided on the side of the diesel engine body 2 near the base 1, and the groove 4 matches the positioning block 3. An installation groove 5 is provided on the lower side of the outer wall of the positioning block 3. A pressure sensor 6 is provided inside the installation groove 5. An installation hole 7 is provided through the middle of the outer wall of the base 1. A pre-tightening bolt 8 is provided inside the installation hole 7. A shear groove 9 is provided radially on the inner wall of the base 1. A buffer block 10 is interference-fitted inside the shear groove 9. A temperature sensor 12 is provided on the inner wall of the base 1 near the shear groove 9. An acceleration sensor 11 is provided on the front side of the outer wall of the base 1. A controller 13 is provided on the left side of the outer wall of the base 1. The pressure sensor 6, temperature sensor 12, and acceleration sensor 11 are respectively connected to the controller 13 through signal lines.

[0036] A washer 33 is provided at the connection between the pre-tightening bolt 8 and the base 1;

[0037] There are 6 shear grooves 9, which are symmetrically distributed inside the base 1. The shear grooves 9 have an arc-shaped variable cross-section structure and the central angle of the shear grooves 9 is 25° to 30°. An exhaust hole 34 is provided on the lower side of the inner wall of the shear grooves 9, and the exhaust hole 34 extends to the outer wall of the base 1.

[0038] Both the positioning block 3 and the positioning block 15 are wedge-shaped, and the wedge angle of both the positioning block 3 and the positioning block 15 is 8° to 12°. There are 3 positioning blocks 3 and 3 positioning blocks 15, and they are distributed at 120°.

[0039] Furthermore, before installing the base 1, the workers cleaned the impurities in the groove 4 and applied a small amount of grease. Pressure sensors 6 were installed in the mounting slots 5 of the three positioning blocks 3 and fixed with epoxy resin encapsulation, ensuring that the surface of the pressure sensor 6 was flush with the lower surface of the positioning block 3. The buffer block 10 was pressed into the shear groove 9 with an interference fit of 0.25mm. Then, the workers aligned the base 1 with the groove 4 on the diesel engine body 2 and inserted it, so that the positioning block 3 was completely embedded in the groove 4. The workers placed the washer 33, screwed the pre-tightening bolt 8 into the mounting hole 7, and applied a standard pre-tightening torque of 140 N·m. The serrated surface of the washer 33 engaged the pre-tightening bolt 8 and the base 1, preventing the pre-tightening bolt from being engaged. 8. Reversal: During normal operation of the diesel engine, the initial preload ensures that the positioning block 3 and the groove 4 fit tightly together. When the diesel engine body 2 vibrates, the base 1 tends to move upwards. The normal pressure between the wedge-shaped slopes increases linearly with the increase of vibration acceleration, causing the self-locking force to increase synchronously. That is, the greater the vibration amplitude of the diesel engine body 2, the tighter the lock between the base 1 and the diesel engine body 2. The vibration and impact generated by the diesel engine body 2 are transmitted through the base 1 body. For low-frequency vibrations of 2-200Hz, the base 1 directly transmits the vibration signal, ensuring the measurement accuracy of the vibration signal. For high-frequency vibrations above 200Hz and instantaneous impacts exceeding 50g, the metal-rubber buffer block 10 in the shear groove 9 undergoes shearing. Deformation converts vibration energy into heat dissipation. The shear groove 9 has a variable cross-section shape that gradually changes from 4mm on the inner side to 6mm on the outer side. Different vibration frequencies will excite the deformation of the buffer block 10 at different positions. When the buffer block 10 deforms, the vent hole 34 can prevent the buffer block 10 from compressing and generating cavitation. The pressure sensor 6 monitors the positive pressure of the corresponding positioning block 3 in real time. The controller 13 sums the three pressure values ​​and converts them into the actual total preload. The fit between the positioning block 3 and the groove 4 is judged by the pressure distribution. The temperature sensor 12 collects the internal temperature of the base 1. According to the pre-stored temperature-pressure correction model, the pressure value collected by the pressure sensor 6 is dynamically compensated to eliminate the measurement error caused by temperature drift. During operation, if the pressure value collected by pressure sensor 6 deviates by more than 15%, controller 13 determines that the mating surface between positioning block 3 and groove 4 is worn, and the staff will carry out maintenance. If temperature sensor 12 detects that the internal temperature of base 1 exceeds 100℃ or is lower than -20℃, controller 13 will notify the staff to carry out maintenance. If a sudden severe sea condition causes the diesel engine body 2 to generate an instantaneous impact of more than 60g, acceleration sensor 11 will detect the impact signal, and controller 13 will record the impact time, amplitude and spectrum. At the same time, it will detect the status of pressure sensor 6 to determine whether the instantaneous impact has caused the mating surface between positioning block 3 and groove 4 to become loose or damaged. If there is an abnormality, the staff will be notified to carry out maintenance.

[0040] Example 2: Please refer to Figure 1 , Figure 3 and Figure 8 A safety monitoring device for a marine low-speed diesel engine propulsion system, wherein a mounting base 14 is provided on the upper side of the outer wall of the base 1, a positioning block 2 15 is provided on the lower side of the inner wall of the mounting base 14, a vibration hole 16 is provided through the lower side of the outer wall of the mounting base 14, and a socket 17 is provided on the lower side of the inner wall of the mounting base 14. The socket 17 is connected to the controller 13 through a signal line.

[0041] A monitoring box 18 is provided on the upper side of the outer wall of the mounting base 14. A groove 19 is provided on the lower side of the outer wall of the monitoring box 18. The groove 19 matches the positioning block 15. A pin 20 is provided on the lower side of the outer wall of the monitoring box 18. The pin 20 cooperates with the socket 17. A sensitive element 21 is provided inside the monitoring box 18. The sensitive element 21 is connected to the pin 20 through a signal line. A support base 22 is provided circumferentially in the middle of the inner wall of the monitoring box 18. The sensitive element 21 is connected to the support base 22 through a traction rope 23. A damping plate 24 is provided on the outer wall of the sensitive element 21. The two ends of the damping plate 24 are respectively connected to the inner wall of the monitoring box 18 and the outer wall of the sensitive element 21. The monitoring box 18 is filled with silicone gel.

[0042] The monitoring box 18 has 4 sets of limiting posts 35 on the lower side of its inner wall, the support base 22 is symmetrically distributed in a star shape, and there are 6 sets of damping plates 24, which correspond to the positive and negative directions of the X, Y and Z axes of the sensitive element 21.

[0043] Both the positioning block 3 and the positioning block 15 are wedge-shaped, and the wedge angle of both the positioning block 3 and the positioning block 15 is 8° to 12°. There are 3 positioning blocks 3 and 3 positioning blocks 15, and they are distributed at 120°.

[0044] Furthermore, during the installation phase of base 1, the workers align groove 2 19 with positioning block 2 15, place monitoring box 18 on mounting base 14, and insert pin 20 into socket 17. During normal operation, eight highly elastic tungsten wire traction ropes 23 distributed in a star pattern provide uniform elastic support for sensitive element 21 in three dimensions. The natural frequency of sensitive element 21 is designed to be 1400Hz, completely avoiding the main vibration frequency band of the diesel engine. When the diesel engine body 2 experiences low-frequency vibration of 2-200Hz, the traction ropes 23 undergo elastic deformation, separating sensitive element 21 from monitoring box 18 to prevent low-frequency vibration from being directly transmitted to sensitive element 21. When vibration above 200Hz occurs, the metal rubber damping sheet 24 undergoes shear deformation, converting high-frequency vibration energy into heat energy for dissipation. The high-damping silicone gel injected into monitoring box 18 fills the pores, further suppressing the resonance peak of sensitive element 21. When the diesel engine body 2 experiences an instantaneous impact exceeding 200g, the displacement of sensitive element 21 exceeds... 0.5mm, the sensitive element 21 contacts the limiting post 35, the limiting post 35 undergoes elastic deformation, absorbing most of the impact energy, limiting the maximum displacement of the sensitive element 21, preventing the traction rope 23 from breaking or the sensitive element 21 from colliding with the monitoring box 18. After the impact, the limiting post 35 and the sensitive element 21 return to their original positions. The vibration information of the diesel engine body 2 collected by the sensitive element 21 is transmitted to the controller 13 through the pin 20 and the socket 17. The controller 13 amplifies, filters and performs analog-to-digital conversion on the vibration information. During long-term operation, if the traction rope 23 breaks, causing the sensitive element 21 to deviate from the center position, the amplitude and phase of the output of the sensitive element 21 received by the controller 13 will change abruptly, and the signal imbalance in the three directions will exceed 20%. The controller 13 will notify the staff to carry out maintenance. The controller 13 calculates the damping attenuation rate by comparing the high-frequency signal amplitude of the sensitive element 21 and the acceleration sensor 11. When the damping attenuation rate exceeds 30%, it indicates that the damping plate 24 has aged and needs to be replaced.

[0045] Example 3: Please refer to Figure 1 , Figure 3 , Figure 4 and Figure 6 A safety monitoring device for a marine low-speed diesel engine propulsion system, wherein a mounting base 14 is provided on the upper side of the outer wall of the base 1, a positioning block 2 15 is provided on the lower side of the inner wall of the mounting base 14, a vibration hole 16 is provided through the lower side of the outer wall of the mounting base 14, and a socket 17 is provided on the lower side of the inner wall of the mounting base 14. The socket 17 is connected to the controller 13 through a signal line.

[0046] A monitoring box 18 is provided on the upper side of the outer wall of the mounting base 14. A groove 19 is provided on the lower side of the outer wall of the monitoring box 18. The groove 19 matches the positioning block 15. A pin 20 is provided on the lower side of the outer wall of the monitoring box 18. The pin 20 cooperates with the socket 17. A sensitive element 21 is provided inside the monitoring box 18. The sensitive element 21 is connected to the pin 20 through a signal line. A support base 22 is provided circumferentially in the middle of the inner wall of the monitoring box 18. The sensitive element 21 is connected to the support base 22 through a traction rope 23. A damping plate 24 is provided on the outer wall of the sensitive element 21. The two ends of the damping plate 24 are respectively connected to the inner wall of the monitoring box 18 and the outer wall of the sensitive element 21. The monitoring box 18 is filled with silicone gel.

[0047] A vibrator 25 is provided in the middle of the inner wall of the base 1. The vibrator 25 is rigidly connected to the lower side of the inner wall of the base 1. A vibration transmission rod 26 is provided at the output end of the vibrator 25. The vibration transmission rod 26 passes through the vibration hole 16 and contacts the lower side of the outer wall of the monitoring box 18. Sealing rings 27 are provided on both the upper and lower sides of the outer wall of the vibration hole 16. The vibrator 25 is connected to the controller 13 through a signal line.

[0048] The inner wall of the mounting base 14 is provided with a locking hole 36, and a locking ball 37 is provided inside the locking hole 36. A locking spring 38 is provided on the outer wall of the locking ball 37 near the outer wall of the mounting base 14. A push rod 39 is provided on the outer wall of the mounting base 14 corresponding to the locking hole 36. The two ends of the locking spring 38 are connected to the locking ball 37 and the push rod 39 respectively. The outer wall of the monitoring box 18 is provided with a locking groove 40, which matches the locking ball 37.

[0049] Both the positioning block 3 and the positioning block 15 are wedge-shaped, and the wedge angle of both the positioning block 3 and the positioning block 15 is 8° to 12°. There are 3 positioning blocks 3 and 3 positioning blocks 15, and they are distributed at 120°.

[0050] Furthermore, when the staff places the monitoring box 18 on the mounting base 14, during the process of the groove 2 19 and the positioning block 2 15 fitting together, the locking ball 37, under the action of the locking spring 38 and the staff pressing down on the monitoring box 18, extends from the locking hole 36 to retract into the locking hole 36. After the monitoring box 18 is in place, the locking ball 37, under the pushing force of the locking spring 38, cooperates with the locking groove 40 on the outer wall of the monitoring box 18, so that the monitoring box 18 is stably placed on the mounting base 14. During the long-term monitoring of the diesel engine, the staff sets the calibration cycle through the controller 13 to calibrate the sensitive element 21. During calibration, the controller 13 obtains the information collected by the acceleration sensor 11 as the calibration reference value. Subsequently, the controller 13 controls the exciter 25 to output a set of standard sinusoidal sweep frequency signals of 10Hz to 10kHz. The exciter 25 directly transmits the standard vibration to the monitoring box 1 through the vibration transmission rod 26. 8. The sensitive element 21 collects the vibration signal generated by the vibrator 25 and transmits it to the controller 13 through the pin 20 and the socket 17. The controller 13 compares the information collected by the accelerometer 11 and the sensitive element 21. The controller 13 generates a correction coefficient for the sensitive element 21 based on the sensitivity deviation, zero drift and frequency response deviation of the sensitive element 21. The correction coefficient is used to correct the information collected by the sensitive element 21 during subsequent measurements. If the accelerometer 11 does not detect the vibration signal, the acquisition error of the sensitive element 21 exceeds 5%, or the signal of the sensitive element 21 is interrupted during the calibration process, the operator can pull the top rod 39 at the same time. The top rod 39 drives the locking spring 38, causing the locking ball 37 to disengage from the locking groove 40 and enter the locking hole 36. At this time, the operator can raise the monitoring box 18 and separate it from the mounting base 14 to replace or inspect the monitoring box 18.

[0051] Example 4: Please refer to Figure 1 , Figure 2 and Figure 5 A safety monitoring device for a marine low-speed diesel engine propulsion system includes a base 1 and a diesel engine body 2. A positioning block 3 is provided on the lower side of the outer wall of the base 1. A groove 4 is provided on the side of the diesel engine body 2 near the base 1, and the groove 4 matches the positioning block 3. An installation groove 5 is provided on the lower side of the outer wall of the positioning block 3. A pressure sensor 6 is provided inside the installation groove 5. An installation hole 7 is provided through the middle of the outer wall of the base 1. A pre-tightening bolt 8 is provided inside the installation hole 7. A shear groove 9 is provided radially on the inner wall of the base 1. A buffer block 10 is interference-fitted inside the shear groove 9. A temperature sensor 12 is provided on the inner wall of the base 1 near the shear groove 9. An acceleration sensor 11 is provided on the front side of the outer wall of the base 1. A controller 13 is provided on the left side of the outer wall of the base 1. The pressure sensor 6, temperature sensor 12, and acceleration sensor 11 are respectively connected to the controller 13 through signal lines.

[0052] A mounting bracket 28 is provided on the upper side of the outer wall of the base 1. An adjusting motor 29 is provided on the upper side of the outer wall of the mounting bracket 28. A reducer 30 is provided on the lower side of the outer wall of the mounting bracket 28. The reducer 30 is connected to the output end of the adjusting motor 29. A torque sensor 31 is provided on the output end of the reducer 30. A sleeve 32 is connected to the output end of the reducer 30 through a spline. The sleeve 32 cooperates with the pre-tightening bolt 8. The adjusting motor 29, the reducer 30 and the torque sensor 31 are respectively connected to the controller 13 through signal lines.

[0053] A washer 33 is provided at the connection between the pre-tightening bolt 8 and the base 1;

[0054] Furthermore, during long-term monitoring, the controller 13 acquires the pressure value collected by the pressure sensor 6, the internal temperature of the base 1 collected by the temperature sensor 12, and the vibration acceleration value collected by the acceleration sensor 11. The controller 13 sums the pressure values ​​collected by the three pressure sensors 6 to obtain the total preload. At the same time, based on the current temperature value and the pre-stored temperature correction model, the controller performs temperature compensation on the preload to eliminate measurement errors caused by thermal expansion and contraction. The temperature correction model is constructed from the total preload and initial temperature at the initial installation of the equipment. After temperature compensation, if the total preload is lower than 90% of the initial total preload, the controller 13 controls the adjustment motor 29 to start. The adjustment motor 29, after being reduced in speed and increased in torque by the reducer 30, drives the sleeve 32 to rotate the preload bolt 8. The torque sensor 31 at the output end of the reducer 30 detects the adjustment in real time. When the torque sensor 31 detects that the adjustment torque has reached the standard torque of 140 N·m, the controller 13 controls the adjustment motor 29 to stop running. After the adjustment is completed, the controller 13 re-acquires the pressure values ​​collected by the three pressure sensors 6. If the total preload still does not reach 95% of the initial total preload, the controller 13 controls the adjustment motor 29 to perform a second adjustment. If the standard is still not met after three adjustments, the controller 13 notifies the staff to carry out maintenance. If the acceleration sensor 11 detects an instantaneous impact of more than 60g or a temperature change of more than 20℃ / h, the controller 13 immediately acquires the pressure value collected by the pressure sensor 6 and compares it with the initial total preload to ensure that the preload is within the set range. This avoids the base 1 from becoming loose due to preload attenuation caused by vibration, thereby improving the accuracy of information acquisition.

[0055] Example 5: Please refer to Figure 1 , Figure 2 and Figure 3A safety monitoring device for a marine low-speed diesel engine propulsion system includes a base 1 and a diesel engine body 2. A positioning block 3 is provided on the lower side of the outer wall of the base 1. A groove 4 is provided on the side of the diesel engine body 2 near the base 1, and the groove 4 matches the positioning block 3. An installation groove 5 is provided on the lower side of the outer wall of the positioning block 3. A pressure sensor 6 is provided inside the installation groove 5. An installation hole 7 is provided through the middle of the outer wall of the base 1. A pre-tightening bolt 8 is provided inside the installation hole 7. A shear groove 9 is provided radially on the inner wall of the base 1. A buffer block 10 is interference-fitted inside the shear groove 9. A temperature sensor 12 is provided on the inner wall of the base 1 near the shear groove 9. An acceleration sensor 11 is provided on the front side of the outer wall of the base 1. A controller 13 is provided on the left side of the outer wall of the base 1. The pressure sensor 6, temperature sensor 12, and acceleration sensor 11 are respectively connected to the controller 13 through signal lines.

[0056] A monitoring box 18 is provided on the upper side of the outer wall of the mounting base 14. A groove 19 is provided on the lower side of the outer wall of the monitoring box 18. The groove 19 matches the positioning block 15. A pin 20 is provided on the lower side of the outer wall of the monitoring box 18. The pin 20 cooperates with the socket 17. A sensitive element 21 is provided inside the monitoring box 18. The sensitive element 21 is connected to the pin 20 through a signal line. A support base 22 is provided circumferentially in the middle of the inner wall of the monitoring box 18. The sensitive element 21 is connected to the support base 22 through a traction rope 23. A damping plate 24 is provided on the outer wall of the sensitive element 21. The two ends of the damping plate 24 are respectively connected to the inner wall of the monitoring box 18 and the outer wall of the sensitive element 21. The monitoring box 18 is filled with silicone gel.

[0057] Furthermore, when the vessel is not started, the controller 13 acquires information from the acceleration sensor 11 and the sensing element 21, performs zero-point calibration, and eliminates initial deviations. After the vessel starts, the diesel engine begins to run, and the controller 13 acquires vibration data from the acceleration sensor 11 and the sensing element 21, calculates the amplitude transfer function and phase difference between them as a reference model. During the long-term voyage of the vessel, the controller 13 calculates the amplitude ratio, phase difference, and spectral correlation between the acceleration sensor 11 and the sensing element 21 based on the information transmitted by them, and compares it with the reference model. When the information acquired by the acceleration sensor 11 and the sensing element 21 is normal and conforms to the reference model, the average value of the two is taken as the measurement result. When the acceleration sensor 11 or the sensing element 21 malfunctions, the controller 13 uses the part that is not malfunctioning for monitoring to ensure uninterrupted acquisition of the vibration status of the diesel engine body 2. In addition, the controller 13 can also monitor the vibration status of the diesel engine body 2 based on the information from the acceleration sensor 11 and the sensing element 21. The controller 13 uses the signal strength, amplitude ratio, and phase difference to locate equipment faults. If the signal from the accelerometer 11 is normal, but the signal from the sensitive element 21 is abnormal, and the amplitude ratio and phase difference of the two deviate significantly from the reference model, it indicates a fault inside the monitoring box 18. If both signals are abnormal, but the amplitude ratio and phase difference conform to the reference model, it indicates abnormal vibration of the diesel engine body 2. If both signals are normal, but the amplitude ratio and phase difference increase, it indicates a decrease in the installation rigidity of the base 1. If both signals are normal, but the amplitude ratio is significantly abnormal, it indicates wear on the mating surfaces of the positioning block 11 and groove 14 or the positioning block 215 and groove 219. If the signal from the accelerometer 11 is abnormal, but the signal from the sensitive element 21 is normal, and the amplitude ratio and phase difference of the two deviate significantly from the reference, it indicates an abnormality in the accelerometer 11. The controller 13 notifies the staff to carry out maintenance according to the corresponding abnormal conditions, shortening the fault diagnosis time and improving the maintenance efficiency of the staff.

[0058] Working principle: The operator inserts the base 1 into the groove 4 on the diesel engine body 2, so that the positioning block 3 fits into the groove 4. The pre-tightening bolt 8 is screwed into the mounting hole 7, and a standard pre-tightening torque of 140 N·m is applied. When the diesel engine body 2 vibrates, under the action of the wedge-shaped positioning block 3 and the groove 4, the greater the vibration amplitude of the diesel engine body 2, the tighter the locking between the base 1 and the diesel engine body 2. At the same time, the buffer block 10 in the shear groove 9 undergoes shear deformation during vibration, eliminating the vibration effect, so that the pressure sensor 6, temperature sensor 12 and acceleration sensor 11 can accurately collect information from the base 1 and the diesel engine body 2.

[0059] During long-term monitoring, the traction rope 23 and the damping plate 24 provide uniform elastic support in three dimensions for the sensitive element 21. When vibrating, the traction rope 23 undergoes elastic deformation, which separates the sensitive element 21 from the monitoring box 18, preventing low-frequency vibration from being directly transmitted to the sensitive element 21. The damping plate 24 undergoes shear deformation to cancel the vibration, ensuring accurate information collection from the sensitive element 21.

[0060] When the monitoring box 18 malfunctions, the operator can pull the top rod 39, which drives the locking spring 38, causing the locking ball 37 to disengage from the locking groove 40 and enter the locking hole 36, thus releasing the locking of the monitoring box 18 and allowing it to be replaced. The total preload collected by the pressure sensor 6 is compared with the initial total preload. If it is lower than the initial total preload, the controller 13 controls the adjustment motor 29 to start. After the adjustment motor 29 is reduced in speed and increased in torque by the reducer 30, it drives the sleeve 32 to rotate the preload bolt 8. When the torque sensor 31 detects that the adjustment torque reaches the standard torque of 140 N·m, the controller 13 controls the adjustment motor 29 to stop running. After the adjustment is completed, a second test is performed. If it is still lower than the initial total preload, a second adjustment is performed, up to a maximum of three adjustments.

[0061] The controller 13 acquires the initial vibration data collected by the accelerometer 11 and the sensing element 21, calculates the amplitude transfer function and phase difference between them as a reference model. In the subsequent monitoring process, the controller 13 calculates the amplitude ratio, phase difference and spectral correlation between the two based on the information transmitted by the accelerometer 11 and the sensing element 21, and compares it with the reference model. When the information collected by the accelerometer 11 and the sensing element 21 is normal and conforms to the reference model, the average value of the two is taken as the measurement result.

[0062] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A safety monitoring device for a marine low-speed diesel engine propulsion system, characterized in that: Includes a base (1) and a diesel engine body (2). A positioning block (3) is provided on the lower side of the outer wall of the base (1). A groove (4) is provided on the side of the diesel engine body (2) near the base (1). The groove (4) matches the positioning block (3). A mounting groove (5) is provided on the lower side of the outer wall of the positioning block (3). A pressure sensor (6) is installed inside the mounting groove (5). A mounting hole (7) is provided through the middle of the outer wall of the base (1). A pre-tightening bolt is installed inside the mounting hole (7). 8) A shear groove (9) is radially provided on the inner wall of the base (1). A buffer block (10) is interference-fitted inside the shear groove (9). A temperature sensor (12) is provided on the inner wall of the base (1) near the shear groove (9). An acceleration sensor (11) is provided on the front side of the outer wall of the base (1). A controller (13) is provided on the left side of the outer wall of the base (1). The pressure sensor (6), temperature sensor (12) and acceleration sensor (11) are respectively connected to the controller (13) through signal lines.

2. The safety monitoring instrument for a marine low-speed diesel engine propulsion system according to claim 1, characterized in that: The base (1) has an upper mounting seat (14) on its outer wall, a positioning block (15) on the lower inner wall of the mounting seat (14), a vibration hole (16) through the lower outer wall of the mounting seat (14), and a socket (17) on the lower inner wall of the mounting seat (14). The socket (17) is connected to the controller (13) via a signal line.

3. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 2, characterized in that: The upper side of the outer wall of the mounting base (14) is provided with a monitoring box (18), the lower side of the outer wall of the monitoring box (18) is provided with a groove two (19), the groove two (19) matches the positioning block two (15), the lower side of the outer wall of the monitoring box (18) is provided with a pin (20), the pin (20) cooperates with the socket (17), the monitoring box (18) is provided with a sensitive element (21), the sensitive element (21) is connected to the pin (20) through a signal line, the middle of the inner wall of the monitoring box (18) is provided with a support base (22), the sensitive element (21) is connected to the support base (22) through a traction rope (23), the outer wall of the sensitive element (21) is provided with a damping plate (24), the two ends of the damping plate (24) are connected to the inner wall of the monitoring box (18) and the outer wall of the sensitive element (21) respectively, and the monitoring box (18) is filled with silicone gel.

4. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 2, characterized in that: A vibrator (25) is provided in the middle of the inner wall of the base (1). The vibrator (25) is rigidly connected to the lower side of the inner wall of the base (1). A vibration transmission rod (26) is provided at the output end of the vibrator (25). The vibration transmission rod (26) passes through the vibration hole (16) and contacts the lower side of the outer wall of the monitoring box (18). Sealing rings (27) are provided on both the upper and lower sides of the outer wall of the vibration hole (16). The vibrator (25) is connected to the controller (13) through a signal line.

5. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 1, characterized in that: The base (1) has an upper mounting bracket (28) on its outer wall, an adjustment motor (29) on its upper outer wall, a reducer (30) on its lower outer wall, the reducer (30) connected to the output end of the adjustment motor (29), a torque sensor (31) on the output end of the reducer (30), a sleeve (32) connected to the output end of the reducer (30) via a spline, and the sleeve (32) engaging with the pre-tightening bolt (8). The adjustment motor (29), the reducer (30) and the torque sensor (31) are connected to the controller (13) via signal lines.

6. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 1, characterized in that: A washer (33) is provided at the connection between the pre-tightening bolt (8) and the base (1).

7. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 1, characterized in that: There are 6 shear grooves (9). The shear grooves (9) are symmetrically distributed inside the base (1). The shear grooves (9) are arc-shaped variable cross-section structures. The central angle of the shear grooves (9) is 25° to 30°. An exhaust hole (34) is provided on the lower side of the inner wall of the shear grooves (9). The exhaust hole (34) extends to the outer wall of the base (1).

8. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 3, characterized in that: The monitoring box (18) has 4 sets of limiting posts (35) on the lower side of the inner wall, the support base (22) is symmetrically distributed in a cross shape, and there are 6 sets of damping plates (24). The damping plates (24) correspond to the positive and negative directions of the X, Y and Z axes of the sensitive element (21).

9. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 2, characterized in that: The inner wall of the mounting base (14) is provided with a locking hole (36), and a locking ball (37) is provided inside the locking hole (36). A locking spring (38) is provided on the outer wall of the locking ball (37) near the outer wall of the mounting base (14). A push rod (39) is provided on the outer wall of the mounting base (14) corresponding to the locking hole (36). The two ends of the locking spring (38) are connected to the locking ball (37) and the push rod (39) respectively. A locking groove (40) is provided on the outer wall of the monitoring box (18), and the locking groove (40) matches the locking ball (37).

10. A safety monitoring device for a marine low-speed diesel engine propulsion system according to claim 2, characterized in that: Both the positioning block 1 (3) and the positioning block 2 (15) are wedge-shaped, and the wedge angles of both the positioning block 1 (3) and the positioning block 2 (15) are 8° to 12°. There are 3 positioning blocks 1 (3) and 3 positioning blocks 2 (15), and both the positioning blocks 1 (3) and the positioning blocks 2 (15) are distributed at 120°.

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