A cutter head rigidity protection device for a trailing suction hopper dredger

Abstract

This invention discloses a drag suction hopper dredger head stiffness protection device, comprising a drag suction hopper head, the top end of which is connected to a front connecting plate, the front connecting plate being hinged to the output end of a hydraulic rod via a first pivot; a variable stiffness assembly is connected to the base end of the hydraulic rod, the other end of which is connected to a support base, the support base being hinged to a rear connecting plate via a second pivot, the rear connecting plate being connected to the top end of a rear housing; wherein, the front end of the rear housing is connected to a front housing, and the front end of the front housing is connected to the drag suction hopper head; the drag suction hopper head is hinged to the rear housing via a third pivot. The purpose of this invention is to overcome the shortcomings of existing devices and provide a drag suction hopper head stiffness protection device that can simultaneously ensure drag suction hopper head cutting stability and impact resistance.

Description

Technical Field

[0001] This invention relates to a device for protecting the stiffness of the rake head of a trailing suction hopper dredger. Background Technology

[0002] As a core piece of equipment in dredging projects, the connection structure between the trailing suction hopper and the rear hull of the dredging vessel directly affects the stability, safety, and efficiency of dredging operations. In particular, the performance of the connection structure is crucial in dredging scenarios involving complex geological formations.

[0003] Currently, the trailing suction hopper dredger's head and aft hull are typically connected by rigid joints, fixed hinges, or passive buffer structures such as rubber pads and mechanical springs. While these existing technologies can generally meet the normal dredging requirements of trailing suction hopper dredgers in soft strata such as ordinary silt, silt, and clay, they still have significant technical limitations in complex strata such as strongly weathered rock, semi-weathered rock, boulders, localized bedrock protrusions, and alternating layers of soft and hard rock, making them unsuitable for complex operational conditions.

[0004] Specifically, when the rake head is dragged, raked, and cut in undulating rock geological environments, once it comes into contact with hard layers or obstacles, the resulting impact load and vibration will be directly transmitted to the front housing, rear housing, shaft, and mud discharge pipe through the connection parts. This can easily lead to damage to the rake teeth, fatigue failure of the connecting parts, local deformation of the housing, and damage to the mud discharge system, seriously affecting the continuity of operation and the service life of the equipment.

[0005] Existing buffering solutions using rubber pads, mechanical springs, etc., can only provide fixed stiffness and passive energy absorption effects. They cannot be actively adjusted according to real-time changes in geological conditions and operating conditions. Therefore, it is difficult to simultaneously meet the needs of the rake head's posture stability under normal dredging conditions and the buffering protection requirements under abnormal collision conditions. The targetedness and effectiveness of buffering protection are poor.

[0006] Furthermore, while some existing buffering or vibration reduction solutions possess a certain energy absorption capacity, they are mostly designed for single-directional loads or general engineering machinery scenarios. They are ill-suited to the multi-directional complex force conditions experienced by the draghead during underwater operations, such as vertical swaying, lateral deflection, and localized oblique collisions, resulting in insufficient comprehensive buffering protection. Existing active buffering solutions, such as hydraulic buffers, face practical application challenges, including complex structures, high sealing requirements, difficult maintenance, and difficulty in achieving circumferential zoning in the confined area near the draghead's shaft. These limitations hinder their widespread application at the draghead connection points of trailing suction hopper dredgers.

[0007] In summary, the existing connection structure between the dredger head and the rear hull of the trailing suction hopper dredger is ineffective in dealing with the impact of hard layers, boulders, and rock protrusions during dredging in complex geological formations. This can easily cause damage to the dredger head and related structures, affecting operational efficiency and equipment safety, and failing to meet the requirements for intelligent and efficient dredging operations.

[0008] Therefore, a device for protecting the stiffness of the rake head of a trailing suction hopper boat is proposed to address the above problems. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of existing devices and provide a drag suction hopper head stiffness protection device that can simultaneously take into account the cutting stability of the drag head and the impact protection capability.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a device for protecting the stiffness of the dragline head of a trailing suction hopper dredger, comprising: A rake head, the top of which is connected to a front connecting plate, the front connecting plate being hinged to the output end of a hydraulic rod via a first rotating shaft; A variable stiffness assembly is connected to the base end of the hydraulic rod, and the other end of the variable stiffness assembly is connected to a support base. The support base is hinged to a rear connecting plate via a second pivot, and the rear connecting plate is connected to the top of the rear housing. The front end of the rear box is connected to the front box, and the front end of the front box is connected to the rake head; the rake head is hinged to the rear box via a third rotating shaft.

[0011] Preferably, the variable stiffness component includes: A sealed outer shell, one end of which is connected to the support base, and the other end has a first opening, through which a pressure-bearing base is connected; The first pressure-bearing rod is slidably connected inside the sealed housing, and the outer wall is connected to multiple sets of circumferentially arranged elastomer assemblies. The second pressure rod has one end connected to the base end of the hydraulic rod and the other end having a second opening. The end of the sealing shell with the first opening is located inside the second pressure rod.

[0012] Preferably, the elastomer assembly includes: A magnetic shielding sleeve, wherein the interior of the magnetic shielding sleeve is filled with a magnetorheological elastomer, and a third opening is provided on one side of the magnetic shielding sleeve, and a pressure ring is provided at the third opening; An excitation coil is arranged around the outside of the magnetorheological elastomer. The excitation coil is electrically connected to an external power generator through a power line, and the stiffness of the magnetorheological elastomer is adjusted by the change of the magnetic field.

[0013] Preferred options also include: A spring is disposed between the first pressure-bearing rod and the pressure-bearing base.

[0014] Preferred options also include: A limiting ring is fitted around the outside of multiple sets of elastic body components arranged circumferentially on the outer wall of the first bearing rod.

[0015] Preferably, a retractable sealing shell is connected between the open end of the second bearing rod and the support base.

[0016] Preferably, the rear end of the rear box is connected to a sludge discharge pipe.

[0017] Preferably, the lower end of the rake head is connected to rake teeth.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The rigidity protection device for the rake head of this trailing suction hopper vessel, by setting an annular segmented elastomer assembly in the main load transmission area between the rake head, the front box and the rear box, combined with the segmented magnetic isolation design of the magnetic isolation sleeve, the real-time current adjustment function of the power generator, and the stable force path of "rake head, front connecting plate, hydraulic rod, pressure rod, pressure ring, magnetorheological elastomer, support base and rear box", can not only effectively buffer the impact load generated during operation in complex strata such as strongly weathered rock, semi-weathered rock and boulders, but also reduce the transmission of the impact peak to the front box, rear box, third rotating shaft and mud discharge pipe, avoid damage to the rake teeth, connecting parts, box and mud discharge system, ensure the continuity of operation and extend the service life of the equipment; It can also adjust the excitation coil current in real time according to the impact level through the power generator, realize the dynamic switching between high rigidity support under normal working conditions and local reduction of rigidity and energy absorption under risky working conditions, take into account the posture stability of the rake head during normal cutting and the buffer protection needs during abnormal collisions, and solve the problems of traditional passive buffer structures being unable to actively adjust and having poor protection targeting. Meanwhile, the annular segmented arrangement of the elastomer components can adapt to the multi-directional complex force conditions during underwater operation of the dredging head, such as vertical swinging, left and right deflection, and local oblique collisions, improving the comprehensiveness of buffer protection and making it more adaptable than single-directional buffering schemes. In addition, this device does not require the arrangement of complex hydraulic circuits, has a simple structure and reliable sealing, and can be arranged in annular sections in a small area near the dredging head shaft. This overcomes the problems of complex structure, difficult maintenance and limited promotion of existing active buffering schemes, making it easier for engineering applications and subsequent maintenance. Ultimately, it meets the needs of intelligent and efficient dredging operations, significantly improving the stability, safety and efficiency of trailing suction hopper dredgers in complex strata. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram showing the location of the drag suction hopper head stiffness protection device of the present invention; Figure 2 This is a detailed view of the location of the drag suction hopper head stiffness protection device of the present invention; Figure 3 This is a detailed view of the variable stiffness component of the present invention; Figure 4 This is a detailed view of the connection of the spring of the present invention; Figure 5 This is a detailed view of the location of the magnetorheological elastomer of the present invention; Figure 6 This is a cross-sectional schematic diagram of the variable stiffness component of the present invention.

[0020] In the diagram: 1. Rake head; 2. Front connecting plate; 3. First rotating shaft; 4. Hydraulic rod; 5. Support base; 6. Second rotating shaft; 7. Rear connecting plate; 8. Rear housing; 9. Front housing; 10. Third rotating shaft; 11. Sealing shell; 12. Pressure-bearing base; 13. First pressure-bearing rod; 14. Second pressure-bearing rod; 15. Magnetic shielding sleeve; 16. Magnetorheological elastomer; 17. Pressure ring; 18. Excitation coil; 19. Power supply line; 20. Power generator; 21. Spring; 22. Limiting ring; 23. Telescopic sealing shell; 24. Sludge discharge pipe; 25. Rake teeth. Detailed Implementation

[0021] 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.

[0022] like Figure 1-6 As shown, a scraper head stiffness protection device for a trailing suction hopper includes a scraper head 1. The top of the scraper head 1 is connected to a front connecting plate 2, which is hinged to the output end of a hydraulic rod 4 via a first rotating shaft 3. A variable stiffness assembly is connected to the base end of the hydraulic rod 4, and the other end of the variable stiffness assembly is connected to a support base 5. The support base 5 is hinged to a rear connecting plate 7 via a second rotating shaft 6, and the rear connecting plate 7 is connected to the top of a rear housing 8. The front end of the rear housing 8 is connected to a front housing 9, and the front end of the front housing 9 is connected to the scraper head 1. The scraper head 1 is hinged to the rear housing 8 via a third rotating shaft 10. A sludge discharge pipe 24 is connected to the rear end of the rear housing 8. Scraper teeth 25 are connected to the lower end of the scraper head 1.

[0023] Specifically, the variable stiffness assembly includes a sealing shell 11, one end of which is connected to a support base 5, and the other end has a first opening, with a pressure-bearing base 12 connected inside. A first pressure-bearing rod 13 is slidably connected inside the sealing shell 11, and its outer wall is connected to multiple sets of circumferentially arranged elastic body components. It also includes a limiting ring 22, which is sleeved on the outside of the multiple sets of circumferentially arranged elastic body components on the outer wall of the first pressure-bearing rod 13. A spring 21 is also included, disposed between the first pressure-bearing rod 13 and the pressure-bearing base 12. A second pressure-bearing rod 14 is connected at one end to the base end of a hydraulic rod 4, and the other end has a second opening. The end of the sealing shell 11 with the first opening is located inside the second pressure-bearing rod 14. A retractable sealing shell 23 is connected between the open end of the second pressure-bearing rod 14 and the support base 5.

[0024] Specifically, there are twelve groups of elastomer components, which can be divided into upper, lower, left, and right sections, with each functional area containing three elastomer components. Further subdivisions can be made as needed, clockwise into: upper front section 1, upper front section 2, upper rear section 1, upper rear section, upper rear middle section, lower rear section, lower rear middle section, lower rear section, lower front section 2, lower front section 1, lower front middle section, and upper front middle section, to improve the accuracy of identifying and adjusting the direction of local impacts.

[0025] Specifically, the elastomer assembly includes a magnetic shielding sleeve 15, which is filled with a magnetorheological elastomer 16. A third opening is provided on one side of the magnetic shielding sleeve 15, and a pressure ring 17 is provided at the third opening. An excitation coil 18 is arranged around the outside of the magnetorheological elastomer 16. The excitation coil 18 is electrically connected to an external power generator 20 through a power line 19, and the stiffness of the magnetorheological elastomer 16 is adjusted by the change of the magnetic field.

[0026] During operation, the trailing suction hopper dredger propels the entire device forward. The rake teeth 25 at the lower end of the rake head 1 contact the mud and rock layers at the bottom of the water to complete the dredging operation. The rake head 1 and the front box 9 are hinged to the rear box 8 by the third rotating shaft 10, which can generate small-angle swing and deflection, adapting to complex underwater operating environments. The working load, towing reaction force and collision impact force are transmitted sequentially through the rake head 1, the front connecting plate 2 and the first rotating shaft 3 to the hydraulic rod 4. Then, the hydraulic rod 4 is transmitted sequentially through the second bearing rod 14 and the first bearing rod 13 to multiple sets of circumferentially arranged elastic body components. Finally, it is transmitted to the rear box 8 through the support base 5, the second rotating shaft 6 and the rear connecting plate 7, forming a complete force flow transmission path. The mud and sand generated by dredging are transported to the mud discharge pipe 24 through the rake head 1, the front box 9 and the rear box 8 for discharge.

[0027] Under normal dredging conditions, the variable stiffness component, as the core component for stiffness adjustment and buffer protection of the device, has its internal structures working together to ensure operational stability: the external power generator 20 provides stable power to the excitation coil 18 through the power line 19. The excitation coil 18 is arranged around the outside of the magnetorheological elastomer 16. After being energized, it generates a constant magnetic field. Under the action of the magnetic field, the shear modulus of the magnetorheological elastomer 16 is significantly increased, maintaining high shear modulus and high equivalent support stiffness; at the same time, the spring 21 between the first bearing rod 13 and the bearing base 12 is in a pre-tightened state, forming a composite support structure with the magnetorheological elastomer 16, which together provide stable support for the entire device, keeping the rake head 1 in a fixed working posture, ensuring the support strength of the overall structure and the stability of dredging operations, avoiding excessive shaking or displacement of the rake head 1, and ensuring the orderly progress of routine dredging operations. The sealed outer shell 11 in the variable stiffness assembly completely covers all internal structures. The telescopic sealing shell 23 is connected between the open end of the second pressure-bearing rod 14 and the support base 5. The two work together to form a fully enclosed protection for the internal magnetorheological elastomer 16, excitation coil 18, first pressure-bearing rod 13, pressure ring 17 and other pressure-bearing structures. This effectively prevents underwater silt, water and impurities from intruding, avoids jamming and damage to the internal structure due to foreign object interference, and ensures the stable operation of the variable stiffness assembly.

[0028] When the rake teeth 25 and rake head 1 encounter obstacles such as hard layers, boulders, or protruding rock formations at the bottom of the water and are subjected to sudden impact loads or lateral compressive forces, the variable stiffness component quickly activates its buffer adjustment function. The working process is as follows: The impact load transmitted by the hydraulic rod 4 directly acts on the second bearing rod 14. The second bearing rod 14 drives the first bearing rod 13, which is linked to it, to slide axially along the inside of the sealed shell 11. The pressure ring 17 connected to the outer wall of the first bearing rod 13 simultaneously applies pressure to the magnetorheological elastomer 16, causing the magnetorheological elastomer 16 to deform. At this time, the power generator 20 adjusts the power supply current of the excitation coil 18 in the corresponding area in real time according to the impact direction and impact intensity, changes the magnetic field strength, and then dynamically controls the modulus and damping characteristics of the magnetorheological elastomer 16. When the current decreases, the magnetic field weakens, and the shear modulus of the magnetorheological elastomer 16 decreases accordingly, so that the elastomer component in the loaded area quickly switches to a low stiffness, high energy absorption state, and efficiently absorbs impact energy. Simultaneously, the spring 21 between the first bearing rod 13 and the bearing base 12 is compressed, further buffering the impact through its own elastic deformation. This forms a synergistic buffering effect with the magnetorheological elastomer 16, effectively reducing the peak impact load. It also provides controlled clearance displacement between the rake head 1 and the rear housing 8, buffering complex impact forces from multiple directions and preventing rigid impacts from directly damaging the hydraulic rod 4, the front housing 9, the rear housing 8, and all hinged connections. During this process, the magnetic shielding sleeve 15 wraps around the magnetorheological elastomer 16 and the excitation coil 18, effectively constraining the magnetic field range, preventing magnetic field leakage to adjacent elastomer components, ensuring the independence of adjustment for each elastomer component, and ensuring the accuracy of the variable stiffness component adjustment.

[0029] The variable stiffness component adopts a structure in which multiple sets of elastomer components are arranged in a ring around the first bearing rod 13. Each set of elastomer components consists of a magnetic shielding sleeve 15, a magnetorheological elastomer 16, a pressure ring 17, and an excitation coil 18. Multiple sets of components work together to form a ring-shaped buffer support layer, which can achieve differentiated and zoned stiffness adjustment for impact loads in different directions such as the upper, lower, left, right and corners, and accurately match multi-directional stress conditions. When impacted in different directions, the elastomer components in the corresponding areas can independently complete stiffness adjustment, while adjacent components maintain stable support, which not only ensures the buffering effect, but also avoids loss of overall structural attitude control. The limiting ring 22 is fitted onto the outside of multiple sets of elastomer components. Its installation position is determined according to the maximum allowable compression stroke of the magnetorheological elastomer 16. It can limit the maximum sliding stroke of the first bearing rod 13, thereby constraining the ultimate compression deformation of the magnetorheological elastomer 16 and preventing the magnetorheological elastomer 16 from breaking due to excessive deformation under large impact conditions. At the same time, it avoids overload damage to components such as the pressure ring 17 and the first bearing rod 13, further ensuring the structural integrity and operational reliability of the variable stiffness assembly. In addition, the sealing shell 11 not only serves as a sealing and protective function, but also provides stable installation support for the internal pressure base 12, the first bearing rod 13, and the elastomer components, ensuring that the relative positions of each component are fixed and ensuring the smoothness of the variable stiffness assembly adjustment process.

[0030] The telescopic sealing shell 23 is connected between the open end of the second pressure rod 14 and the support base 5. It can deform synchronously with the axial extension and retraction of the first pressure rod 13 and the second pressure rod 14, and continuously maintain a sealed state. This further prevents underwater mud, water and impurities from entering the interior of the sealing shell 11, ensuring that the variable stiffness component can work stably for a long time under harsh underwater conditions, and significantly improving the overall service life and operational reliability of the device.

[0031] The variable stiffness component, as the core of the device's stiffness adjustment and buffer protection, relies on the synergistic effect of its internal magnetorheological elastomer, excitation coil, and pressure-bearing structure to achieve three differentiated working modes, adapting to the stiffness adjustment and impact protection needs under different operating conditions. The specific working principle is as follows: Working Mode 1: When the trailing suction hopper is performing straight dredging, the rake teeth 25 at the lower end of the rake head 1 contact the rock layer at the bottom of the water ahead, causing the lower or upper part of the rake head 1 to collide and thus causing an upward or downward swinging posture deviation. The hinge structure (third rotating shaft 10) between the rake head 1 and the rear box 8 rotates, and the impact load is transmitted to the variable stiffness component along the axial direction of the hydraulic rod 4. At this time, all circumferentially arranged elastomer components bear a uniform load. The power generator 20 simultaneously reduces the power supply current of the excitation coil 18 in all segmented elastomer components, and the magnetic field strength is simultaneously weakened. The shear modulus of the magnetorheological elastomer 16 in each elastomer component is reduced, so that all segmented units are switched to a low stiffness energy absorption state. At the same time, the spring 21 is simultaneously compressed, and works with the magnetorheological elastomer 16 to evenly share the impact load, effectively reducing the peak impact value and reducing the transmission of vibration to the rake head 1 connecting structure (front connecting plate 2, first rotating shaft 3) and the rear box 8, avoiding overload damage to each component due to axial impact.

[0032] Working Mode 2: If, during the operation of the trailing suction hopper, the left side of the drag head 1 is subjected to a lateral collision with the underwater rock layer and experiences lateral sway, the lateral impact load mainly acts on the elastomer component in the left region of the variable stiffness assembly. The left-side segmented unit bears the main load, while the elastomer components in the upper and lower regions bear the secondary load due to attitude deviation. At this time, the power generator 20 prioritizes reducing the excitation current of the excitation coil 18 in the left-side segmented unit, causing the magnetorheological elastomer 16 in the left-side elastomer component to quickly switch to a low-stiffness state and assume the main buffering and energy absorption role. At the same time, the excitation current of the elastomer components in the upper and lower regions is appropriately reduced in a symmetrical manner, so that the stiffness of the magnetorheological elastomer 16 in the corresponding region is appropriately reduced, which helps to share the lateral impact load and avoid local load concentration. The current reduction in each region is adjusted in real time according to the impact intensity. The greater the impact intensity, the greater the current reduction and the more significant the stiffness adjustment. When the right side of the rake head 1 is subjected to a lateral collision, its control method is completely symmetrical to the collision process on the left side. The right side segmented unit prioritizes the main buffer energy absorption, while the upper and lower regions assist in sharing the load.

[0033] Working Mode 3: When the rake teeth 25 of a certain corner area of ​​the front end of the rake head 1 comes into contact with a boulder or a local protrusion of a hard layer on the bottom of the water, the impact load is concentrated on one or a few segment units on the corresponding impact direction. The segment unit in this area is given priority to be loaded, and the segment units in adjacent areas assist in sharing the load. The power generator 20 identifies the impact position and, combined with the relative distance between each segment unit and the impact position, performs gradient adjustment on the current of the excitation coil 18 of all segment units. Among them, the closer the segment unit is to the impact position, the greater the reduction in excitation current, the more significant the reduction in the shear modulus of the corresponding magnetorheological elastomer 16, and the smaller the equivalent stiffness, thus prioritizing local buffering and energy absorption, and quickly absorbing the concentrated impact energy. The farther the segment unit is from the impact position, the smaller the reduction in excitation current, or the higher the current level is maintained. The corresponding magnetorheological elastomer 16 maintains a higher equivalent stiffness, providing external support and attitude constraint for the entire device, preventing the rake head 1 from swaying significantly due to local impact, ensuring the stability of the device's operating posture, and avoiding local overload damage to the variable stiffness components caused by concentrated impact.

[0034] In all three operating modes, the magnetic sleeve 15 in the variable stiffness assembly always plays a role in magnetic field confinement, reducing magnetic field crosstalk between adjacent segment units and ensuring the independence of stiffness adjustment of each segment unit; the limiting ring 22 always limits the maximum sliding stroke of the first pressure rod 13 to avoid excessive compression and damage to the magnetorheological elastomer 16; the sealing shell 11 and the retractable sealing shell 23 work together to achieve sealing protection, ensuring that the variable stiffness assembly can stably and smoothly switch between the three operating modes under complex underwater conditions, and ensuring long-term reliable operation of the device.

[0035] This trailing suction hopper's rake head stiffness protection device, by setting an annular segmented elastomer assembly in the main load transmission area between the rake head 1, the front housing 9, and the rear housing 8, combined with the segmented magnetic isolation design of the magnetic isolation sleeve 15, the real-time current adjustment function of the power generator 20, and the stable force path of "rake head 1, front connecting plate 2, hydraulic rod 4, pressure rod, pressure ring 17, magnetorheological elastomer 16, support base 5, and rear housing 8", can not only effectively buffer the impact load generated during operation in complex strata (strongly weathered rock, semi-weathered rock, boulders, etc.), but also reduce the transmission of the impact peak to the front housing 9, rear housing 8, third rotating shaft 10, and mud discharge pipe 24, thus avoiding damage to the rake teeth 25, connecting parts, housing, and mud discharge system, ensuring continuous operation and extending the service life of the equipment; It can also adjust the current of the excitation coil 18 in real time according to the impact level through the power generator 20, realize the dynamic switching between high rigidity support under normal working conditions and local reduction of rigidity and energy absorption under risky working conditions, take into account the posture stability of the rake head 1 during normal cutting and the buffer protection requirements during abnormal collisions, and solve the problems of traditional passive buffer structure being unable to actively adjust and having poor protection targeting. Meanwhile, the annular segmented arrangement of the elastomer components can adapt to the multi-directional complex force conditions such as up-and-down swinging, left-and-right deflection, and local oblique collisions during underwater operation of the dredging head 1, improving the comprehensiveness of buffer protection and making it more adaptable than single-directional buffer schemes. In addition, this device does not require the arrangement of complex hydraulic circuits, has a simple structure and reliable sealing, and can be arranged in a ring-shaped partition in a small area near the shaft of the dredging head 1. This overcomes the problems of complex structure, high maintenance difficulty and difficulty in promotion of existing active buffer schemes, making it convenient for engineering application and later maintenance. Ultimately, it meets the needs of intelligent and efficient dredging operations and significantly improves the operational stability, safety and efficiency of the trailing suction hopper dredger in complex strata.

[0036] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for protecting the stiffness of the rake head of a trailing suction hopper dredger, characterized in that, include: Rake head (1), the top of the rake head (1) is connected to the front connecting plate (2), and the front connecting plate (2) is hinged to the output end of the hydraulic rod (4) through the first rotating shaft (3); A variable stiffness assembly is connected to the base end of the hydraulic rod (4), and the other end of the variable stiffness assembly is connected to the support base (5). The support base (5) is hinged to the rear connecting plate (7) through the second rotating shaft (6). The rear connecting plate (7) is connected to the top of the rear box (8). The front end of the rear box (8) is connected to the front box (9), and the front end of the front box (9) is connected to the rake head (1); the rake head (1) is hinged to the rear box (8) through a third rotating shaft (10).

2. The trailing suction hopper dredger head stiffness protection device according to claim 1, characterized in that, The variable stiffness component includes: The sealed outer shell (11) is connected to the support base (5) at one end and has a first opening at the other end, with a pressure-bearing base (12) connected inside. The first pressure-bearing rod (13) is slidably connected inside the sealed housing (11), and the outer wall is connected to a plurality of circumferentially arranged elastomer assemblies; The second pressure rod (14) is connected at one end to the base end of the hydraulic rod (4) and has a second opening at the other end. The end of the sealing shell (11) with the first opening is located inside the second pressure rod (14).

3. The trailing suction hopper rake head stiffness protection device according to claim 2, characterized in that, The elastomer assembly includes: A magnetic shielding sleeve (15) is filled with a magnetorheological elastomer (16). A third opening is provided on one side of the magnetic shielding sleeve (15), and a pressure ring (17) is provided at the third opening. An excitation coil (18) is arranged around the outside of the magnetorheological elastomer (16). The excitation coil (18) is electrically connected to an external power generator (20) through a power line (19). The stiffness of the magnetorheological elastomer (16) is adjusted by the change of the magnetic field.

4. The trailing suction hopper rake head stiffness protection device according to claim 2, characterized in that, Also includes: A spring (21) is disposed between the first pressure-bearing rod (13) and the pressure-bearing base (12).

5. The trailing suction hopper rake head stiffness protection device according to claim 2, characterized in that, Also includes: The limiting ring (22) is sleeved on the outside of the multiple sets of elastic body components arranged circumferentially on the outer wall of the first bearing rod (13).

6. The trailing suction hopper dredger head stiffness protection device according to claim 2, characterized in that, A retractable sealing shell (23) is connected between the open end of the second pressure rod (14) and the support base (5).

7. The trailing suction hopper dredger head stiffness protection device according to claim 1, characterized in that, The rear end of the rear box (8) is connected to a mud discharge pipe (24).

8. The trailing suction hopper dredger head stiffness protection device according to claim 1, characterized in that, The lower end of the rake head (1) is connected to rake teeth (25).

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