Active and passive composite shock absorber with composite stiffness

Abstract

The invention relates to the technical field of ship supplies, and discloses an active and passive composite shock absorber with composite stiffness. The passive vibration reduction assembly comprises a rhombus structure, the upper end is connected with the load platform, and the lower end is connected with the base. The extension spring is transversely installed in the rhombus structure and used for reducing transverse deformation of the rhombus structure. The resistance element is longitudinally mounted in the rhombic structure and generates a damping effect based on electromagnetic induction to attenuate vibration; the axial oil buffer is fixedly connected with the load platform and used for resisting impact in the vertical direction, and the transverse oil buffer is fixedly connected with a partition plate longitudinally arranged on the base and used for resisting impact in the horizontal direction. According to the device, the rigidity is enhanced by adopting the composite spring with the rhombus structure, the transverse deformation of the rhombus structure can be prevented, the axial and radial rigidity of the rhombus structure is ensured, and the higher bearing capacity of the system is ensured. The resistance element can further absorb and dissipate vibration energy, so that the amplitude is reduced when the system is excited, and damage caused by excessive vibration is prevented.

Description

Technical Field

[0001] The present application relates to the technical field of marine supplies, for example, to an active and passive composite shock absorber with composite stiffness, which can be used as auxiliary equipment for combat vehicles, warships, aircraft and ships. Background Art

[0002] The integration of electronic equipment is the key to promoting the transformation of equipment towards informatization, automation and intelligence. However, these electronic devices are often placed in extreme environments, such as combat vehicles, ships, aircraft and vessels. The various unstable conditions they face, such as ground bumps, wave impacts and high-altitude air flow disturbances, will cause strong vibrations and shocks. This poses a severe challenge to electronic equipment and may cause functional damage or even failure. Therefore, the research and development of vibration reduction technology is particularly important.

[0003] Existing vibration reduction technologies are mainly divided into two categories: passive and active. Passive control does not require external energy, and only generates control force by the movement of the controlled structure, and its energy comes from the structure itself. This technology has the advantages of small space occupation, simple design, and reliable performance, but it is not able to suppress low-frequency characteristic line spectrum vibration.

[0004] Active vibration isolation technology requires external energy support and consists of energy supply equipment, sensors, controllers and actuators. When external disturbances cause system vibrations, the sensors capture the information, the controller processes and issues instructions, and the actuators apply force to offset the vibration. However, relying solely on traditional passive vibration reduction technology is difficult to fully reduce the impact of vibration during the operation of ship equipment.

[0005] Therefore, a combination of active and passive vibration reduction is a better choice. Passive vibration reduction can effectively broaden the vibration reduction bandwidth and improve high-frequency transmission, while active vibration reduction is good at suppressing low-frequency resonance peaks. The two complement each other and can achieve efficient vibration reduction in a wider frequency range.

[0006] Chinese patent CN112211952A proposes a low-frequency, large-stroke, quasi-zero stiffness vibration isolation device, which maintains quasi-zero stiffness characteristics within a displacement of 100mm through a diamond spring and an adjustable limit support structure, effectively isolating low-frequency vibrations. However, the device has not yet proposed a more efficient solution for resonance peak suppression.

[0007] Another Chinese patent CN106523568A invented a damping-amplifying vibration isolator, which uses a diamond-shaped four-bar linkage structure and a damper design to amplify the vibration isolator damping coefficient, reduce the resonance amplification coefficient, and improve the vibration isolation effect. However, the increase in damping may have a certain impact on high-frequency transmissibility.

[0008] In summary, although the existing technology has made some progress in vibration reduction, it still needs continuous exploration and optimization to better meet the urgent needs of military electronic equipment for vibration reduction technology.

[0009] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0010] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical elements or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0011] The embodiment of the present disclosure provides an active and passive composite shock absorber with composite stiffness, which can improve the positive stiffness of the system and ensure a strong bearing capacity of the system.

[0012] In some embodiments, the active-passive composite vibration damper comprises a load platform, a base and a passive vibration damping component, wherein the passive vibration damping component comprises: A diamond-shaped structure, the upper end of which is connected to the load platform, and the lower end of which is connected to the base; A tension spring is installed transversely in the diamond structure to reduce the transverse deformation of the diamond structure; A resistance element is longitudinally mounted in the diamond structure, wherein the resistance element produces a damping effect based on electromagnetic induction to attenuate vibration; The oil buffer comprises an axial oil buffer and a transverse oil buffer. The axial oil buffer is fixedly connected to the load platform for resisting impact in the vertical direction, and the transverse oil buffer is fixedly connected to a partition arranged longitudinally on the base for resisting impact in the horizontal direction.

[0013] Optionally, the diamond structure includes: A diamond-shaped sheet, used to support the diamond-shaped structure; A connecting portion, surrounding the diamond-shaped piece and connected to the outer periphery of the diamond-shaped piece, the connecting portion being used to connect the diamond-shaped piece to the load platform and the base; Two transverse protruding shafts are respectively connected to the inner side of the connecting part. One end of the transverse protruding shaft away from the connecting part is provided with a through hole, and the tension spring is connected to the diamond structure through the through hole.

[0014] Optionally, the two transverse protruding axes are located on the same plane, and the plane passes through the center of the diamond structure.

[0015] Optionally, the resistance element comprises: A magnetic rod, the upper end of which is fixedly connected to the upper end of the rhombus structure; A copper tube, the lower end of which is fixedly connected to the lower end of the diamond structure, and the copper tube is sleeved outside the magnetic rod; When the active and passive composite shock absorber is impacted in the longitudinal direction, the magnetic rod moves relatively in the copper tube.

[0016] Optionally, the transfer function of the passive vibration reduction component is:

[0017] In the formula, is the vibration response displacement of the load platform, is the vibration displacement of the base platform, is the equivalent damping of the passive vibration reduction mechanism, is the equivalent stiffness between the load platform and the base platform of the passive vibration reduction mechanism, is the mass of the load platform, which is expressed in the complex domain. is the complex frequency variable in the Laplace transform.

[0018] Optionally, the active-passive composite vibration absorber further includes an active vibration reduction component, and the active vibration reduction component includes: Flat-plate voice coil motor, the mover part and the load platform are not fixedly connected to the output shaft; A planar voice coil motor spacer is used to connect the stator part of the planar voice coil motor.

[0019] Optionally, three groups of planar voice coil motors 2 are arranged in a horizontal array.

[0020] Optionally, on the basis of passive vibration reduction, an active feedback control loop is added. The feedback control loop adopts the mode of sensor feedback, controller calculation, and actuator output to form an active and passive composite vibration isolation mechanism. The controller adopts the ceiling damping feedback control algorithm. The transfer function of the active and passive composite vibration reduction mechanism in the closed loop is:

[0021] In the formula, is the vibration response displacement of the load platform, is the vibration displacement of the base platform, is the equivalent damping of the passive vibration reduction mechanism, is the equivalent stiffness between the load platform and the base platform of the passive vibration reduction mechanism, is the mass of the load platform, and this formula is expressed in the complex domain, is the gain factor of the ceiling damping.

[0022] Optionally, the base includes an adjustable height platform assembly, and the adjustable height platform assembly includes: The first basic platform serves as a bottom support seat; The second basic platform is connected to the first basic platform and can adjust the tilt angle. The partition is arranged on the second basic platform. The load platform is connected to the second basic platform through a diamond structure.

[0023] Optionally, the first base platform is provided with a plurality of countersunk holes, and the nut ends of the adjustment studs are fixed in these countersunk holes; The second basic platform is provided with four threaded holes at the countersunk holes corresponding to the first basic platform. The stud of the adjusting bolt is connected to the threaded hole at the lower end of the second basic platform. The fastening bolt is connected to the upper end of the second basic platform through the threaded hole. The inclination angle of the load platform can be adjusted by adjusting the screw-in length of the fastening bolt in the second basic platform.

[0024] The active and passive composite shock absorber with composite stiffness provided in the embodiments of the present disclosure can achieve the following technical effects: The diamond structure composite spring is used to enhance stiffness and realize the high load characteristics of the system. The positive stiffness characteristics of the extension spring are utilized to effectively prevent the lateral deformation of the diamond structure and ensure the axial and radial stiffness of the diamond structure.

[0025] The resistance element uses electromagnetic induction to produce a damping effect, thereby absorbing and dissipating vibration energy. It can maintain stable damping characteristics over a wide temperature range to reduce the amplitude when the system is excited and prevent damage caused by excessive vibration.

[0026] To sum up, the active and passive composite shock absorber with composite stiffness provided in the embodiment of the present disclosure can improve the positive stiffness of the system through the coordination of the diamond structure, tension spring and resistance element, ensure the strong bearing capacity of the system, and weaken the vibration caused by the impact of ships, aircraft and ships in the fluid.

[0027] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein: Figure 1 A three-dimensional structural diagram of an active and passive composite shock absorber with composite stiffness according to an embodiment of the present invention; Figure 2 A front view of an active and passive composite shock absorber with composite stiffness according to an embodiment of the present invention; Figure 3 An exploded view of an active and passive composite shock absorber with composite stiffness according to an embodiment of the present invention; Figure 4It is a front view of the passive vibration reduction part of an active and passive composite vibration absorber with composite stiffness according to an embodiment of the present invention; Figure 5 A three-dimensional structural diagram of a nonlinear stiffness mechanism of a composite stiffness active and passive composite shock absorber with a diamond structure according to an embodiment of the present invention; Figure 6 A three-dimensional structural diagram of a diamond structure mechanism of an active and passive composite shock absorber with composite stiffness according to an embodiment of the present invention; Figure 7 A three-dimensional structural diagram of a composite stiffness active and passive composite shock absorber tension spring mechanism according to an embodiment of the present invention; Figure 8 A three-dimensional structural diagram of an active and passive composite shock absorber damping mechanism with composite stiffness according to an embodiment of the present invention; Fig. 9 A three-dimensional structural diagram of a composite stiffness active and passive composite vibration absorber flat voice coil motor according to an embodiment of the present invention; Fig.10 A three-dimensional structural diagram of an active and passive composite shock absorber oil buffer with composite stiffness according to an embodiment of the present invention; Fig.11 A three-dimensional structural diagram of an active and passive composite shock absorber with a composite stiffness and an adjustable height platform according to an embodiment of the present invention; FIG. 12 ( a ) is a passive vibration reduction principle diagram of an active and passive composite vibration absorber with composite stiffness according to an embodiment of the present invention; FIG12( b ) is a schematic diagram of a precision active vibration reduction principle of an active and passive composite vibration absorber with composite stiffness according to an embodiment of the present invention; Fig.13 It is a comparison diagram of the transmissibility curves under the traditional vibration isolation platform, the passive vibration isolation of the present invention, and the active control of the present invention.

[0029] Explanation of the reference numerals in the accompanying drawings: 1. a partition of a flat-plate voice coil motor; 2. a flat-plate voice coil motor; 3. a first basic platform; 4. an adjustment stud; 5. a second basic platform; 6. a fastening bolt; 7. a diamond structure; 701. a transverse cam shaft; 8. a load platform; 9. a partition; 10. a tension spring; 12. an oil buffer; 1201. a head receiving impact; 1202. a piston rod; 1203. an oil buffer body; 13. a magnetic rod; 14. a copper tube. DETAILED DESCRIPTION

[0030] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0031] The terms "first", "second", etc. in the embodiments of the present disclosure are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so as to describe the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0032] In the embodiments of the present disclosure, the terms "upper", "lower", "inside", "middle", "outside", "front", "back", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are mainly intended to better describe the embodiments of the present disclosure and their embodiments, and are not intended to limit the indicated devices, elements, or components to have specific directions, or to be constructed and operated in specific directions. Moreover, in addition to being used to indicate directions or positional relationships, some of the above terms may also be used to indicate other meanings. For example, the term "upper" may also be used to indicate a certain dependency or connection relationship in certain circumstances. For those of ordinary skill in the art, the specific meanings of these terms in the embodiments of the present disclosure can be understood according to specific circumstances.

[0033] In addition, the terms "disposed", "connected" and "fixed" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0034] Unless otherwise stated, the term "plurality" means two or more.

[0035] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.

[0036] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0037] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

[0038] Combination Figure 1-4 As shown, an embodiment of the present disclosure provides an active and passive composite vibration reduction device with composite stiffness, which includes a load platform 8, a base, a passive vibration reduction component and an active vibration reduction component.

[0039] The base includes an adjustable height platform assembly, which includes a first basic platform 3 and a second basic platform 5, which are jointly equipped with a passive vibration reduction assembly and an active vibration reduction assembly, so that the vibration reduction device has a compact structure and is easy to assemble and disassemble. The first basic platform 3 serves as a bottom support seat, the second basic platform 5 is connected to the first basic platform 3 and can adjust the tilt angle, the partition 9 is arranged on the second basic platform 5, and the load platform 8 is connected to the second basic platform 5 through a diamond structure 7.

[0040] The first basic platform 3 is provided with a plurality of countersunk holes, and the nut ends of the adjusting studs 4 are fixed in these countersunk holes; the second basic platform 5 is provided with threaded holes at the countersunk holes corresponding to the first basic platform 3, and the studs of the adjusting studs 4 are connected to the threaded holes at the lower end of the second basic platform 5, and the fastening bolts 6 are connected to the upper end of the second basic platform 5 through the threaded holes. The inclination angle of the load platform 8 can be adjusted by adjusting the screw-in length of the fastening bolts 6 in the second basic platform 5.

[0041] It is understandable that when the ship equipment moves, there will be a certain angle between the load platform 8 and the horizontal reference plane. By using an adjustable height platform, the load platform 8 can be always in a horizontal position by rotating the fastening bolts 6, ensuring that the load platform 8 is in a horizontal state, thereby limiting the vibration impact of the shock absorber in a non-horizontal direction.

[0042] The passive vibration reduction component includes a diamond structure 7, a tension spring 10, a resistance element and an oil buffer 12. The upper end of the diamond structure 7 is connected to the load platform 8, and the lower end is connected to the base; the tension spring 10 is transversely installed in the diamond structure 7 to reduce the lateral deformation of the diamond structure 7; the resistance element is longitudinally installed in the diamond structure 7, and the resistance element produces a damping effect based on electromagnetic induction to attenuate vibration; the oil buffer 12 includes an axial oil buffer 12 and a transverse oil buffer 12. The axial oil buffer 12 is fixedly connected to the load platform 8 for resisting impact in the vertical direction, and the transverse oil buffer 12 is fixedly connected to the partition 9 longitudinally arranged on the base for resisting impact in the horizontal direction.

[0043] The diamond structure 7 includes a diamond piece and a connecting portion, the diamond piece is used to support the diamond structure 7; the connecting portion surrounds the diamond piece and is connected to the outer periphery of the diamond piece, and the connecting portion is used to connect the diamond piece to the load platform 8 and the base; two lateral protrusions 701 are respectively connected to the inner side of the connecting portion, and a through hole is provided at one end of the lateral protrusion 701 away from the connecting portion, and the tension spring 10 is connected to the diamond structure 7 through the through hole.

[0044] It can be understood that the diamond structure 7 composite spring is used to enhance stiffness and realize the high-load characteristics of the system. The positive stiffness characteristics of the tension spring 10 can effectively prevent the lateral deformation of the diamond structure 7 and ensure the axial and radial stiffness of the diamond structure 7.

[0045] Preferably, the two transverse protruding axes 701 are located on the same plane, and the plane passes through the center of the diamond structure 7 .

[0046] The resistance element includes a magnetic rod 13 and a copper tube 14. The upper end of the magnetic rod 13 is fixedly connected to the upper end of the diamond structure 7; the lower end of the copper tube 14 is fixedly connected to the lower end of the diamond structure 7, and the copper tube 14 is sleeved outside the magnetic rod 13. When the active and passive composite shock absorber is impacted in the longitudinal direction, the magnetic rod 13 moves relatively in the copper tube 14.

[0047] According to Faraday's law of electromagnetic induction, the magnetic field around the magnetic bar 13 will induce eddy currents in the copper tube 14 and generate a secondary magnetic field in the opposite direction to the magnetic field of the magnetic bar 13, thereby forming an electromagnetic damping force that hinders the movement of the magnetic bar 13. This electromagnetic damping force can effectively convert the kinetic energy of the vibration system into heat energy and dissipate it through the resistance of the copper tube 14, thereby achieving effective attenuation of vibration and reducing the instability of the equipment caused by external vibration. This non-contact damping mechanism uses electromagnetic induction to produce a damping effect, thereby absorbing and dissipating vibration energy. It can maintain stable damping characteristics within a wide temperature range to reduce the amplitude when the system is excited and prevent damage caused by excessive vibration. It can be applied to the vibration isolation requirements of shipborne equipment under harsh environmental conditions.

[0048] The oil buffer 12 can be divided into an axial oil buffer 12 and a transverse oil buffer 12 according to the installation position. The axial oil buffer 12 and the transverse oil buffer 12 both include a collision head 1201, a piston rod 1202 and an oil buffer body 1203. The end of the axial oil buffer 12 away from the collision head 1201 is fixedly connected to the load platform 8 for resisting impact in the vertical direction. The end of the transverse oil buffer 12 away from the collision head 1201 is fixedly connected to the partitions 9 on both sides of the second base platform 5 for resisting impact in the horizontal direction.

[0049] When the impact head 1201 is subjected to external impact, the piston rod 1202 is pressed and moved. Since the gap between the piston rod 1202 and the buffer body is very small and filled with oil, the movement of the piston rod 1202 forces the oil to flow through the throttle hole. The viscous resistance of the oil consumes the impact energy, thereby protecting the shock absorber from damage caused by excessive impact.

[0050] The active vibration reduction component includes a flat voice coil motor 2 and a flat voice coil motor 2 partition 91. Based on the vibration signal collected by the sensor, the controller implements real-time active control to drive the flat voice coil motor 2 to generate a corresponding reverse excitation force to offset the vibration of the shipboard equipment.

[0051] As a special linear motor, the flat voice coil motor 2 has the advantages of compact structure, small size, low operating noise and fast response rate. The motor consists of two parts: the mover and the stator. Through a precise control algorithm, the mover of the voice coil motor can perform precise linear motion inside the stator, thereby effectively suppressing vibration.

[0052] The second base platform 5 is provided with four notches for fixing the partition plate 91 of the flat voice coil motor 2. The upper and lower ends of the partition plate 91 of the flat voice coil motor 2 have threaded holes for connecting the stator part of the flat voice coil motor 2. The moving part of the flat voice coil motor 2 is not fixedly connected to the output shaft with the load platform 8.

[0053] It can be understood that the active-passive composite vibration reduction technology is formed by using the diamond structure 7 composite spring as a passive vibration reduction element and the flat voice coil motor 2 as an active vibration reduction element in parallel. Passive vibration reduction is used to effectively broaden the vibration reduction bandwidth and improve the high-frequency transmittance. Active vibration reduction is used to effectively suppress the low-frequency resonance peak. The active and passive composite use forms complementary advantages and achieves efficient vibration reduction effects in a wider frequency range.

[0054] In addition, the contactless design reduces the mechanical coupling between the mover part and the load platform 8, avoiding the additional vibration transmission path caused by direct connection. The lack of fixed connection enables the mover part to respond to the controller's instructions more quickly, simplifies the mechanical structure of the vibration reduction device, reduces potential failure points, and thus achieves high-precision suppression of low-frequency vibrations. The mover can adapt to different load conditions more flexibly and is easy to integrate.

[0055] By adjusting the stiffness of the composite spring assembly of the diamond structure 7 and the exciting force of the flat voice coil motor 2, the vibration reduction frequency band and the resonance peak value can be effectively adjusted, so that the system can adapt to the requirements of shipborne equipment within different frequency ranges.

[0056] As an example, three groups of planar voice coil motors 2 are arranged in a horizontal array to improve redundancy.

[0057] Each group of voice coil motors can be controlled independently, and different parameters (such as force, speed, position, etc.) can be set for each group of motors when in use, so as to perform more precise control. In addition, since there are three groups of motors and they can all be controlled independently, the forces they generate can be vector synthesized. That is, a specific resultant force can be obtained by adjusting the magnitude and direction of the force generated by each group of motors. By using three groups of motors and performing vector synthesis, the output force or position can be controlled more accurately, thereby improving the control accuracy. In addition, the combined use of multiple groups of motors can also improve the dynamic response capability of the system, allowing it to adapt to changes in external conditions more quickly. Through the independent control of the three groups of motors and the vector synthesis of force, a specific reaction force can be generated to offset or suppress this low-frequency resonance, thereby improving the stability and performance of the system. Effectively improve the control accuracy and enhance the dynamic response capability of the system, and achieve effective suppression of low-frequency resonance peaks.

[0058] The active and passive composite vibration reduction control method can effectively improve the isolation effect of low-frequency vibration while maintaining the good attenuation effect of the passive vibration reduction system on medium and high frequency vibration. In addition, by establishing the signal acquisition and output equipment in active control and combining it with an appropriate controller, the performance of the entire system can be further optimized, thereby achieving high-precision suppression of medium and high frequency interference and low-frequency vibration.

[0059] Combination Figure 1 to 1 2, an active and passive composite shock absorber with composite stiffness of this embodiment is described.

[0060] The active and passive composite vibration reduction device with composite stiffness provided in this embodiment includes a load platform 8, an adjustable height platform component, a passive vibration reduction component and an active vibration reduction component.

[0061] The first basic platform 3 is provided with countersunk holes at four corners, and the nut ends of the adjustment studs 4 are fixed in these countersunk holes. The second basic platform 5 is provided with four threaded holes at the countersunk holes corresponding to the first basic platform 3, and the studs of the adjustment studs 4 are connected to the threaded holes at the lower end of the second basic platform 5. The fastening bolts 6 are connected to the upper end of the second basic platform 5 through the threaded holes. By rotating the fastening bolts 6, the inclination angle of the load platform 8 can be adjusted so that it is always in a horizontal position, thereby limiting the vibration impact of the shock absorber in the non-horizontal direction.

[0062] The passive vibration reduction assembly comprises a diamond structure 7, a partition 9, a tension spring 10, an oil buffer 12, and a resistance element, and is intended to suppress vibrations of medium and high frequencies.

[0063] The upper and lower end surfaces of the diamond structure 7 are both provided with threaded holes, and are connected to the load platform 8 and the second base platform 5 through these threaded holes. The tension spring 10 is installed in the diamond structure 7, and the diamond structure 7 is provided with two transverse convex shafts 701 inside. The end of the convex shaft away from the diamond structure 7 is provided with a through hole, and the two ends of the tension spring 10 are fixedly connected to the diamond structure 7 through these through holes. Preferably, the two transverse convex shafts 701 are located on the same plane, and the plane passes through the center of the diamond structure 7. This structure can effectively reduce the lateral deformation of the diamond structure 7, ensure its high stiffness in the axial and radial directions, so as to meet the requirements of the equipment with high load characteristics to support the required vibration isolation.

[0064] like Figure 5 As shown, the resistance element includes a magnetic bar 13 and a copper tube 14, and its design principle is based on the damping effect produced by electromagnetic induction. The upper end of the magnetic bar 13 is fixedly connected to the upper end of the diamond structure 7, and the lower end of the copper tube 14 is fixedly connected to the lower end of the diamond structure 7. When the magnetic bar 13 moves relatively in the copper tube 14, according to Faraday's law of electromagnetic induction, the magnetic field around the magnetic bar 13 will induce eddy currents in the copper tube 14, and generate a secondary magnetic field in the opposite direction to the magnetic field of the magnetic bar, thereby forming an electromagnetic damping force that hinders the movement of the magnetic bar 13. This electromagnetic damping force can effectively convert the kinetic energy of the vibration system into heat energy, and dissipate it through the resistance of the copper tube 14, thereby achieving effective attenuation of vibration and reducing the instability of the equipment caused by external vibration. This non-contact damping mechanism can not only maintain stable damping characteristics in a wide temperature range, but also is suitable for the vibration isolation requirements of shipborne equipment under harsh environmental conditions.

[0065] The oil buffer 12 includes a collision head 1201, a piston rod 1202 and an oil buffer body 1203. According to the installation position, the oil buffer 12 can be divided into an axial oil buffer and a transverse oil buffer. The end of the axial oil buffer away from the collision head 1201 is fixedly connected to the load platform 8, and is used to resist impact in the vertical direction. The end of the transverse oil buffer away from the collision head 1201 is fixedly connected to the partitions 9 on both sides of the second base platform 5, and is used to resist impact in the horizontal direction. When the collision head 1201 is subjected to external impact, the piston rod 1202 is pressed and moved. Since the gap between the piston rod 1202 and the buffer body 1203 is very small and filled with oil, the movement of the piston rod will force the oil to flow through the throttle hole. The viscous resistance of the oil consumes the impact energy, thereby protecting the shock absorber from damage caused by excessive impact.

[0066] The active vibration reduction component includes a flat voice coil motor 2 and a flat voice coil motor partition 1. Based on the vibration signal collected by the sensor, the controller implements real-time active control to drive the flat voice coil motor 2 to generate a corresponding reverse excitation force to offset the vibration of the shipboard equipment.

[0067] The second basic platform 5 is provided with four notches for fixing the planar voice coil motor partition 1. The planar voice coil motor partition 1 has threaded holes at both the upper and lower ends for connecting the stator part of the planar voice coil motor 2.

[0068] The planar voice coil motor 2 is arranged in three groups in a horizontal array to improve redundancy.

[0069] The mover part of the flat voice coil motor 2 is not fixedly connected to the output shaft with the load platform 8. This design reduces the mechanical coupling between the mover part and the load platform 8 and avoids the additional vibration transmission path caused by the direct connection. The lack of a fixed connection enables the mover part to respond to the controller's instructions more quickly, simplifies the mechanical structure of the vibration reduction device, and reduces potential failure points. The mover can adapt to different load conditions more flexibly and is easy to integrate.

[0070] As shown in FIG. 12( a ), the passive vibration reduction mechanism used in the present invention is composed of a spring-mass-damping unit to achieve passive vibration reduction. The transfer function of the system can be written as:

[0071] In the formula, is the vibration response displacement of the load platform, is the vibration displacement of the base platform, is the equivalent damping of the passive vibration reduction mechanism, is the equivalent stiffness between the load platform and the base platform of the passive vibration reduction mechanism, is the mass of the load platform, and this formula is expressed in the complex domain, is the complex frequency variable in the Laplace transform.

[0072] As shown in FIG12( b ), an active and passive composite vibration damper with composite stiffness according to an embodiment of the present invention adds an active feedback control loop on the basis of passive vibration reduction. The feedback control loop operates in a mode of sensor feedback, controller calculation, and actuator output to form an active and passive composite vibration isolation mechanism. In this embodiment, a ceiling damping feedback control algorithm is adopted. The transfer function of the active and passive composite vibration reduction mechanism in the closed loop can be written as:

[0073] In the formula, is the gain factor of the ceiling damping.

[0074] Fig.13 The transmissibility curves of the conventional vibration reduction platform, the passive vibration reduction mode of the present invention, and the active control mode of the present invention are shown.

[0075] It can be seen from the solid line in the figure that the traditional vibration reduction platform has a higher peak in the resonance zone, and its natural frequency is relatively late, resulting in poor attenuation performance in the high frequency band; it can be seen from the dotted line in the figure that in the passive vibration reduction mode of the present invention, the natural frequency is advanced, the resonance peak is partially attenuated, and the vibration reduction bandwidth is increased, thereby showing a better vibration reduction effect.

[0076] It can be seen from the dotted line in the figure that in the active control mode of the present invention, not only the good attenuation performance in the high-frequency band is maintained, but the resonance peak is also compensated by the actively controlled ceiling damping while the damping is increased. It can be seen from the transferability curve that the present invention further improves the vibration reduction performance of the system.

[0077] Compared with the prior art, the technical solution proposed by the present invention has achieved the following technical effects: (1) The active-passive composite vibration reduction technology is formed by using a diamond-shaped composite spring as a passive vibration reduction element and a flat voice coil motor 2 as an active vibration reduction element in parallel. Passive vibration reduction is used to effectively broaden the vibration reduction bandwidth and improve the high-frequency high transmittance. Active vibration reduction is used to effectively suppress the low-frequency resonance peak. The active and passive composite use forms complementary advantages and achieves efficient vibration reduction effects in a wider frequency range.

[0078] (2) A diamond-shaped composite spring is used to enhance stiffness and realize the high-load characteristics of the system. The positive stiffness characteristics of the tension spring 10 are utilized to effectively prevent the lateral deformation of the diamond structure and ensure the axial and radial stiffness of the diamond structure.

[0079] (3) Damping elements use electromagnetic induction to produce a damping effect, thereby absorbing and dissipating vibration energy. They can maintain stable damping characteristics over a wide temperature range to reduce the amplitude when the system is excited and prevent damage caused by excessive vibration.

[0080] (4) When the ship equipment moves, there will be a certain angle between the load platform 8 and the horizontal reference plane. By using an adjustable height platform, the load platform 8 can be always kept in a horizontal position by rotating the fastening bolts 6, ensuring that the load platform 8 is in a horizontal state, thereby limiting the vibration impact of the shock absorber in the non-horizontal direction.

[0081] (5) A flat-plate voice coil motor 2 is used, which occupies a small space, has a compact structure, and has good heat dissipation performance. The linear motion can achieve high dynamics. The non-contact design reduces coupling interference and the complexity of the vibration reduction device, and has a fast response speed, thereby achieving high-precision suppression of low-frequency vibrations.

[0082] (6) By adjusting the stiffness of the diamond-structured composite spring assembly and the exciting force of the flat voice coil motor 2, the vibration reduction frequency band and the resonance peak value can be effectively adjusted, so that the system can adapt to the requirements of shipborne equipment within different frequency ranges.

[0083] (7) The active control link of the voice coil motor adopts three groups of flat-panel voice coil motors 2 in a horizontal array. The independent control technology of the three groups of voice coil motors and the vector synthesis of force are used to effectively improve the control accuracy and enhance the dynamic response capability of the system, thereby achieving effective suppression of low-frequency resonance peaks.

[0084] (8) The active-passive composite vibration reduction control method can effectively improve the isolation effect of low-frequency vibration while maintaining the good attenuation effect of the passive vibration reduction system on medium and high-frequency vibrations. In addition, by establishing signal acquisition and output devices in active control and combining them with appropriate controllers, the performance of the entire system can be further optimized, thereby achieving high-precision suppression of medium and high-frequency interference and low-frequency vibrations.

[0085] To sum up, the embodiments of the present disclosure can improve the positive stiffness of the system through active and passive composite shock absorbers with composite stiffness, ensure the strong bearing capacity of the system, and weaken the vibration of electronic equipment caused by impact on ships, aircraft and ships in fluids, thereby preventing damage to shipborne electronic equipment due to excessive vibration.

[0086] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. The embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An active and passive composite vibration absorber with composite stiffness, comprising a load platform (8), a base and a passive vibration reduction component, characterized in that: The passive vibration reduction component comprises: A diamond-shaped structure (7), the upper end of which is connected to the load platform (8), and the lower end of which is connected to the base; A tension spring (10) is transversely mounted in the diamond structure (7) to reduce the transverse deformation of the diamond structure (7); A resistance element is longitudinally mounted in the diamond structure (7), wherein the resistance element generates a damping effect based on electromagnetic induction to attenuate vibration; The oil buffer (12) comprises an axial oil buffer (12) and a transverse oil buffer (12). The axial oil buffer (12) is fixedly connected to the load platform (8) and is used to resist impact in the vertical direction. The transverse oil buffer (12) is fixedly connected to a partition (9) longitudinally arranged on the base and is used to resist impact in the horizontal direction.

2. The active and passive composite shock absorber according to claim 1, characterized in that: The diamond structure (7) comprises: A diamond-shaped sheet, used to support the diamond-shaped structure (7); A connecting portion, surrounding the diamond-shaped piece and connected to the outer periphery of the diamond-shaped piece, the connecting portion being used to connect the diamond-shaped piece to the load platform (8) and the base; Two transverse protruding shafts (701) are respectively connected to the inner side of the connecting portion; one end of the transverse protruding shaft (701) away from the connecting portion is provided with a through hole, and the tension spring (10) is connected to the diamond structure (7) through the through hole.

3. The active and passive composite shock absorber according to claim 2, characterized in that: The two transverse protruding axes (701) are located on the same plane, and the plane passes through the center of the diamond structure (7).

4. The active and passive composite shock absorber according to claim 1, characterized in that: The resistance element comprises: A magnetic bar (13), the upper end of which is fixedly connected to the upper end of the rhombus structure (7); A copper tube (14), the lower end of which is fixedly connected to the lower end of the diamond structure (7), and the copper tube (14) is sleeved outside the magnetic rod (13); When the active and passive composite shock absorber is impacted in the longitudinal direction, the magnetic bar (13) moves relatively in the copper tube (14).

5. The active and passive composite shock absorber according to claim 1, characterized in that: The transfer function of the passive vibration reduction component is: In the formula, is the vibration response displacement of the load platform (8), is the vibration displacement of the base platform, is the equivalent damping of the passive vibration reduction mechanism, is the equivalent stiffness between the load platform and the base platform of the passive vibration reduction mechanism, is the mass of the load platform, and this formula is expressed in the complex domain, is the complex frequency variable in the Laplace transform.

6. The active and passive composite shock absorber according to any one of claims 1 to 5, characterized in that: Also included is an active vibration reduction assembly, the active vibration reduction assembly comprising: A flat-plate voice coil motor (2), wherein the mover part and the load platform (8) are not fixedly connected to the output shaft; A flat-plate voice coil motor partition (1) is used to connect the stator part of the flat-plate voice coil motor (2).

7. The active and passive composite shock absorber according to claim 6, characterized in that: Three groups of flat-plate voice coil motors (2) are arranged in a horizontal array.

8. The active and passive composite shock absorber according to claim 6, characterized in that: On the basis of passive vibration reduction, an active feedback control loop is added. The feedback control loop adopts the mode of sensor feedback, controller calculation, and actuator output to form an active and passive composite vibration isolation mechanism. The controller adopts the ceiling damping feedback control algorithm. The transfer function of the active and passive composite vibration reduction mechanism in the closed loop is: In the formula, is the vibration response displacement of the load platform (8), is the vibration displacement of the base platform, is the equivalent damping of the passive vibration reduction mechanism, is the equivalent stiffness between the load platform and the base platform of the passive vibration reduction mechanism, is the mass of the load platform, and this formula is expressed in the complex domain, is the gain factor of the ceiling damping.

9. The active and passive composite shock absorber according to claim 8, characterized in that: The base includes an adjustable height platform assembly, and the adjustable height platform assembly includes: A first basic platform (3) serving as a bottom support seat; The second basic platform (5) is connected to the first basic platform (3) and has an adjustable inclination angle. The partition (9) is arranged on the second basic platform (5). The load platform (8) is connected to the second basic platform (5) via a diamond structure (7).

10. The active and passive composite shock absorber according to claim 9, characterized in that: The first basic platform (3) is provided with a plurality of countersunk holes, and the nut ends of the adjustment studs (4) are fixed in these countersunk holes; The second basic platform (5) is provided with four threaded holes at the countersunk holes corresponding to the first basic platform (3); the stud of the adjusting bolt (4) is connected to the threaded hole at the lower end of the second basic platform (5); the fastening bolt (6) is connected to the upper end of the second basic platform (5) through the threaded hole; and the inclination angle of the load platform (8) can be adjusted by adjusting the screw-in length of the fastening bolt (6) in the second basic platform (5).

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