A rotating isolation assembly for a propulsion shafting of a submersible vehicle and a submersible vehicle

Abstract

The present application relates to the technical field of underwater vehicle, and particularly relates to a rotating vibration isolation assembly of an underwater vehicle propulsion shaft system, which comprises a vibration isolation fixing frame and a quasi-zero stiffness unit, the vibration isolation fixing frame comprises a vibration isolation inner ring and a vibration isolation outer ring, the vibration isolation inner ring is fixedly installed on the propulsion shaft of the underwater vehicle, the vibration isolation inner ring and the vibration isolation outer ring are fixedly connected through side ribs, and the vibration isolation inner ring is coaxial with the vibration isolation outer ring, the quasi-zero stiffness unit is installed in the gap between the vibration isolation inner ring and the vibration isolation outer ring, the quasi-zero stiffness unit has a fixed end and a movable end, the fixed end is fixedly connected to the vibration isolation fixing frame, the vibration isolation fixing frame and the quasi-zero stiffness unit rotate synchronously when the propulsion shaft rotates, the movable end of the quasi-zero stiffness unit can deform to different degrees according to the change of centrifugal force, so that the dynamic stiffness of the quasi-zero stiffness unit can be effectively reduced at various rotating speeds, so that the system can enter the high-efficiency vibration isolation area even at a very low excitation frequency, and the acoustic performance of the underwater vehicle is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of underwater vehicle technology, specifically to a rotary vibration isolation assembly for an underwater vehicle propulsion shaft system and an underwater vehicle. Background Technology

[0002] During operation, the vibration generated by the propulsion shaft system of an unmanned underwater vehicle (UUV) is the primary internal sound source. This noise is transmitted to the hull through the shaft system and further radiates outward, forming significant underwater structural acoustic radiation. This not only affects the acoustic stealth of the UUV but may also interfere with the normal operation of its own acoustic detection equipment. Therefore, effectively suppressing axial vibration transmission is one of the keys to improving the acoustic performance of UUVs. Traditional vibration isolation for rotating shaft systems typically uses rubber rings or metal springs. These linear vibration isolators have the problem of fixed natural frequencies: the vibration isolation effect improves when the rotational speed (excitation frequency) increases, but the vibration is amplified severely when crossing the resonance zone during start-up and shutdown. In recent years, quasi-zero stiffness (QZS) vibration isolators have been widely studied due to their high static stiffness and low dynamic stiffness characteristics. However, existing QZS devices mostly rely on gravity as a static load and have fixed stiffness, making them unable to adapt to the dynamic loads that change with rotational speed in rotating machinery. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a rotational vibration isolation assembly for a submarine propulsion shaft system, comprising: The vibration isolation mounting bracket includes an inner vibration isolation ring and an outer vibration isolation ring. The inner vibration isolation ring is fixedly installed on the propulsion shaft of the submersible. The inner vibration isolation ring and the outer vibration isolation ring are fixedly connected by side ribs. The inner vibration isolation ring and the outer vibration isolation ring are coaxial. The side ribs are evenly distributed radially around the propulsion shaft. Quasi-zero stiffness units are evenly spaced circumferentially between the inner and outer vibration isolation rings. Each quasi-zero stiffness unit has a fixed end and a movable end. The fixed end is fixedly connected to the vibration isolation frame, and the movable end is connected to the fixed end at a location away from the connection point with the vibration isolation frame. When the propulsion shaft rotates with the vibration isolation frame, the movable end can respond to centrifugal force and deform to reduce the dynamic stiffness of the quasi-zero stiffness unit.

[0004] Preferably, the quasi-zero stiffness structure includes a curved beam, the two ends of which are respectively connected to the inner vibration isolation ring and the outer vibration isolation ring and form the fixed end at the connection, the middle part of the curved beam is connected to a counterweight block and forms the movable end, and the extension curves of the curved beam extending from the inner vibration isolation ring and the outer vibration isolation ring toward the middle are symmetrical to each other. The curved beams include clockwise and counterclockwise curved beams, and each set of clockwise and counterclockwise curved beams is symmetrically arranged with respect to a certain diameter of the vibration isolation fixing frame.

[0005] Preferably, the extended curve of the curved beam is one of the peaks of a cosine curve, and the part of the curved beam connecting the inner and outer vibration isolation rings is two troughs adjacent to the peak of the cosine curve.

[0006] Preferably, a mounting part is connected to the middle of the curved beam, and the counterweight is fixedly installed in the mounting part.

[0007] Preferably, the vibration isolation bracket is made of stainless steel, and the curved beam is made of spring steel.

[0008] Preferably, two sets of side ribs are provided along the axial direction of the propulsion shaft, and the end faces of the two sets of side ribs facing away from each other are flush with the end faces of the inner and outer rings of the vibration isolation ring, respectively.

[0009] On the other hand, the present invention also provides a submersible, wherein the propulsion shaft of the submersible's propulsion shaft system is equipped with a rotary vibration isolation component as described in any of the above claims.

[0010] Preferably, multiple rotary vibration isolation components are installed at axial intervals on the propulsion shaft.

[0011] This invention provides a rotational vibration isolation assembly for a submersible's propulsion shaft system, comprising a vibration isolation bracket and a quasi-zero stiffness unit. The vibration isolation bracket includes an inner vibration isolation ring and an outer vibration isolation ring. The inner vibration isolation ring is fixedly mounted on the submersible's propulsion shaft, and the inner and outer vibration isolation rings are fixedly connected by side ribs, with the inner and outer rings coaxial. The quasi-zero stiffness unit is installed in the gap between the inner and outer vibration isolation rings, and has a fixed end and a movable end. The fixed end is fixedly connected to the vibration isolation bracket, and the movable end is located away from the connection point between the fixed end and the vibration isolation bracket. During submersible operation... When the propulsion shaft rotates, the vibration isolation bracket and the quasi-zero stiffness unit mounted on the propulsion shaft rotate synchronously. The movable end of the quasi-zero stiffness unit can deform to different degrees according to the change of centrifugal force. Therefore, the dynamic stiffness of the quasi-zero stiffness unit can be effectively reduced at various speeds, thereby reducing the equivalent natural frequency of the system. This allows the system to enter the high-efficiency vibration isolation zone even at very low excitation frequencies (e.g., low-frequency vibrations generated during the start-up, shutdown, low-speed operation, or speed change of the propulsion shaft). This effectively reduces the structural noise output by the submersible into the water and improves the acoustic performance of the submersible. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the rotating vibration isolation assembly of the propulsion shaft system of a submarine provided in an embodiment of the present invention, installed on the propulsion shaft; Figure 2 This is a schematic diagram of the rotating vibration isolation assembly of the propulsion shaft system of a submarine provided in an embodiment of the present invention; Figure 3This is a side view of the rotating vibration isolation assembly of the propulsion shaft system of a submarine provided in an embodiment of the present invention; Figure 4 yes Figure 3 Sectional view of section AA; Figure 5 This is a partial structural schematic diagram of the rotating vibration isolation assembly of the propulsion shaft system of a submarine provided in an embodiment of the present invention; Figure 6 yes Figure 5 A diagram from another perspective; Figure 7 This is a schematic diagram of the structure of the underwater vehicle provided in an embodiment of the present invention; Among them, 1. Rotary vibration isolation assembly; 11. Vibration isolation inner ring; 12. Vibration isolation outer ring; 13. Side rib; 14. Quasi-zero stiffness unit; 141. Curved beam; 1411. Fixed end; 1412. Movable end; 142. Counterweight; 143. Mounting part; 2. Propulsion shaft; 3. Motor; 4. Propeller; 5. Submarine power section. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0014] like Figure 1 and Figure 2As shown, this invention provides a rotational vibration isolation assembly for a submarine propulsion shaft system. The rotational vibration isolation assembly 1 includes a vibration isolation fixing frame and quasi-zero stiffness units 14. The vibration isolation fixing frame includes an inner vibration isolation ring 11, an outer vibration isolation ring 12, and side ribs 13. The inner vibration isolation ring 11 is fixedly installed on the propulsion shaft 2 of the submarine. The outer vibration isolation ring 12 is coaxially arranged with the inner vibration isolation ring 11. The outer vibration isolation ring 12 and the inner vibration isolation ring 11 are fixedly connected by a plurality of side ribs 13. The side ribs 13 are evenly distributed radially around the propulsion shaft 2, that is, the center of mass of the vibration isolation fixing frame is located on the axis of the propulsion shaft 2. The quasi-zero stiffness units 14 are evenly spaced circumferentially in the gap between the inner vibration isolation ring 11 and the outer vibration isolation ring 12. Inside, the quasi-zero stiffness unit 14 has a fixed end 1411 and a movable end 1412. The fixed end 1411 is fixedly connected to the vibration isolation frame, and the movable end 1412 is connected to the part of the fixed end 1411 away from the connection with the vibration isolation frame. When the propulsion shaft 2 and the vibration isolation frame rotate, the quasi-zero stiffness unit 14 rotates synchronously. At this time, the movable end 1412 can deform to different degrees according to the change of centrifugal force, which can reduce the dynamic stiffness of the quasi-zero stiffness unit 14. Therefore, it can reduce the equivalent natural frequency of the system, so that the system can enter the high-efficiency vibration isolation zone at a lower excitation frequency. Thus, it can reduce the noise output of the submersible into the water and improve the acoustic performance of the submersible. Furthermore, since the movable end 1412 deforms to different degrees according to the different centrifugal forces generated by the different rotation speeds of the propulsion shaft 2, it can deform accordingly and reach a lower natural frequency even during the start-up, shutdown, or speed change phases of the propulsion shaft 2. Therefore, it can adapt to the dynamic loads that change with rotation speed in rotating machinery, reduce the dynamic loads and stress amplitudes borne by the shaft system, and improve the vibration isolation performance of the system.

[0015] like Figure 3 and Figure 4 As shown, the quasi-zero stiffness structure 14 includes a curved beam 141. The two ends of the curved beam 141 are connected to the inner vibration isolation ring 11 and the outer vibration isolation ring 12, respectively. The connection between the curved beam 141 and the inner vibration isolation ring 11 and the outer vibration isolation ring 12 forms a fixed end 1411. A counterweight 142 is connected to the middle of the curved beam 141. The middle of the curved beam 141 and the counterweight 142 form a movable end 1412. That is, when the propulsion shaft 2 rotates, the vibration isolation frame rotates synchronously with the propulsion shaft 2. The fixed ends 1411 at both ends of the curved beam 141 and the vibration isolation frame are in a relatively static state. The movable end 1412 in the middle of the curved beam 141 and the counterweight 142 can generate relative motion with respect to the fixed end 1411 and the vibration isolation frame under the action of centrifugal force. That is, the movable end 1412 deforms according to the centrifugal force, thereby reducing the equivalent natural frequency of the system.

[0016] Combination Figure 4The curved beam 141 extends symmetrically from the inner vibration isolation ring 11 and the outer vibration isolation ring 12 towards the center. The counterweight 142 is connected at the symmetrical point in the middle of the curved beam 141, so that the centrifugal force can be evenly applied to the center of symmetry of the curved beam 141. Therefore, when the curved beam 141 is under pressure, it can generate stable and predictable radial deformation along its axis of symmetry, thereby accurately achieving quasi-zero stiffness. In addition, the two ends of the curved beam 141 are fixedly connected to the inner vibration isolation ring 11 and the outer vibration isolation ring 12, while the middle part is in a suspended state. The midpoint is the position where the maximum deformation can occur. Therefore, by setting the counterweight 142 at the symmetrical point in the middle of the curved beam 141, the maximum deformation of the curved beam 141 can be generated with the minimum mass of the counterweight 142 and the speed of the propulsion shaft 2, thereby improving the working efficiency of the quasi-zero stiffness unit 14. The curved beam 141 includes clockwise and counterclockwise curved beams. Each set of clockwise and counterclockwise curved beams is symmetrical with respect to a certain diameter of the vibration isolation frame. This ensures that whether the propulsion shaft 2 rotates clockwise or counterclockwise, the movable end 1412 of each set of curved beams can deform under the action of centrifugal force in the forward direction (i.e., in the direction from the curved beam 141 to the counterweight 142 it is connected to), thereby exerting its vibration isolation effect.

[0017] like Figure 4 As shown, the extended curve of the curved beam 141 is one of the peaks of a cosine curve, and the points where the curved beam 141 connects to the inner vibration isolation ring 11 and the outer vibration isolation ring 12 are two troughs adjacent to the peak of the cosine curve of the curved beam 141. This arrangement ensures that the curved beam 141 between the inner and outer vibration isolation rings 11 and 12 is a smoothly transitioning curve with uniform curvature changes. This results in a more uniform stress distribution when the curved beam 141 deforms, and facilitates the establishment of a force-deformation correlation function for the curved beam 141, making design calculations easier. Of course, the curved beam 141 can also be any other beam shape, as long as it can undergo predictable deformation under centrifugal force.

[0018] The vibration isolation inner ring 11, vibration isolation outer ring 12, and side ribs 13 of the vibration isolation bracket can be made of high-strength stainless steel or other materials, while the curved beam 141 can be made of spring steel or other materials, and the counterweight 142 can be made of any suitable material with counterweight function. Furthermore, the quasi-zero stiffness unit 14 can also be an elastic element with nonlinear stiffness characteristics made of other materials and structures. That is, the fixed end 1411 and the movable end 1412 are not limited to the structures provided in the above embodiments and accompanying drawings, as long as they can utilize the centrifugal force of rotation as a preload to adaptively adjust a nonlinear elastic element to its quasi-zero stiffness working point. After understanding the working principle of this invention, those skilled in the art can design the corresponding quasi-zero stiffness unit 14 structure according to actual conditions, which will not be elaborated here.

[0019] like Figures 4 to 6 As shown, a mounting part 143 is connected to the middle of the curved beam 141, and a counterweight 142 is fixedly installed in the mounting part 143. By setting the mounting part 143, the curved beam 141 can be connected to counterweights 142 of various specifications (mainly different densities) through the mounting part 143, thereby improving the flexibility and adaptability of the rotating vibration isolation assembly 1. Figures 4 to 6 In the illustrated embodiment, the mounting portion 143 is a cylindrical structure, and the counterweight 142 can be fixedly connected to the mounting portion 143 by means of interference fit, welding, or threaded connection. In some other embodiments, the mounting portion 143 may also be a structure of other shapes, and the structure of the corresponding counterweight 142 may also be adapted accordingly, which will not be elaborated here.

[0020] In one preferred embodiment, two sets of side ribs 13 are provided along the axial direction of the propulsion shaft 2. The end faces of the two sets of side ribs 13 facing away from each other are flush with the end faces of the inner and outer rings of the vibration isolation ring 11 and the outer ring 12, respectively. By providing two sets of side ribs 13, the connection strength between the inner and outer rings of the vibration isolation ring 11 can be improved, thereby improving the structural strength of the vibration isolation fixing frame and the rotating vibration isolation assembly.

[0021] Furthermore, such as Figure 5 and Figure 6 As shown, in one preferred embodiment, multiple curved beams 141 can be axially arranged between the inner vibration isolation ring 11 and the outer vibration isolation ring 12 (in... Figure 5 and Figure 6 There are three curved beams 141, which are connected to the same fixed part 143 and the same counterweight 142. By arranging multiple curved beams 141 at intervals along the axial direction, the curved beams 141 connect the fixed part 143 and the counterweight 142, which have a large volume (mainly axial length), while the curved beams 141 themselves have a small axial length. Therefore, each curved beam 141 is more likely to deform based on centrifugal force, which can improve the working effect of the quasi-zero stiffness unit 14.

[0022] like Figure 7 As shown, the present invention also provides a submersible, which includes a submersible power section 5. A motor 3 is installed within the power section 5, and the output end of the motor 3 is connected to a propulsion shaft 2. A propeller 4 is installed at the tail end of the propulsion shaft 2. The propulsion shaft 2 is equipped with the aforementioned rotary vibration isolation assembly 1, which can achieve high static load and low dynamic response, resulting in quieter and more stable power transmission. Furthermore, multiple rotary vibration isolation assemblies 1 can be installed on the propulsion shaft 2 of the submersible to further enhance vibration isolation capabilities and improve the acoustic performance of the submersible.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A rotary vibration isolation assembly for a submersible propulsion shaft system, characterized in that, include: The vibration isolation mounting bracket includes an inner vibration isolation ring and an outer vibration isolation ring. The inner vibration isolation ring is fixedly installed on the propulsion shaft of the submersible. The inner vibration isolation ring and the outer vibration isolation ring are fixedly connected by side ribs. The inner vibration isolation ring and the outer vibration isolation ring are coaxial. The side ribs are evenly distributed radially around the propulsion shaft. Quasi-zero stiffness units are evenly spaced circumferentially between the inner and outer vibration isolation rings. Each quasi-zero stiffness unit has a fixed end and a movable end. The fixed end is fixedly connected to the vibration isolation frame, and the movable end is connected to the fixed end at a location away from the connection point with the vibration isolation frame. When the propulsion shaft rotates with the vibration isolation frame, the movable end can respond to centrifugal force and deform to reduce the dynamic stiffness of the quasi-zero stiffness unit.

2. The rotational vibration isolation assembly for the propulsion shaft system of a submersible according to claim 1, characterized in that, The quasi-zero stiffness structure includes a curved beam, the two ends of which are respectively connected to the inner vibration isolation ring and the outer vibration isolation ring and form the fixed end at the connection. A counterweight is connected to the middle of the curved beam and forms the movable end. The extension curves of the curved beam extending from the inner vibration isolation ring and the outer vibration isolation ring toward the middle are symmetrical to each other. The curved beams include clockwise and counterclockwise curved beams, and each set of clockwise and counterclockwise curved beams is symmetrically arranged with respect to a certain diameter of the vibration isolation fixing frame.

3. The rotational vibration isolation assembly for the propulsion shaft system of a submersible according to claim 2, characterized in that, The extended curve of the curved beam is one of the peaks of the cosine curve, and the part of the curved beam that connects the inner and outer vibration isolation rings is two troughs adjacent to the peak of the cosine curve.

4. The rotational vibration isolation assembly for the propulsion shaft system of a submersible according to claim 2, characterized in that, A mounting part is connected to the middle of the curved beam, and the counterweight is fixedly installed in the mounting part.

5. The rotational vibration isolation assembly for the propulsion shaft system of a submersible according to claim 2, characterized in that, The vibration isolation bracket is made of stainless steel, and the curved beam is made of spring steel.

6. The rotational vibration isolation assembly for the propulsion shaft system of a submersible according to claim 1, characterized in that, Two sets of side ribs are provided along the axial direction of the propulsion shaft. The end faces of the two sets of side ribs facing away from each other are flush with the end faces of the inner and outer rings of the vibration isolation ring, respectively.

7. A submersible, characterized in that, The propulsion shaft of the underwater vehicle is equipped with a rotary vibration isolation assembly as described in any one of claims 1 to 6.

8. The underwater vehicle according to claim 7, characterized in that, Multiple rotary vibration isolation components are installed at axial intervals on the propulsion shaft.

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