Active three-direction rigidity adjustable vibration isolator

Abstract

The invention relates to the technical field of vibration isolation, and discloses an active three-direction rigidity adjustable vibration isolator. The outer layer structure comprises an upper cover, a shell and a buffer assembly comprising a metal rubber pad, the buffer assembly is connected with the shell, the upper cover is in threaded connection with the shell, and the density of the metal rubber pad is controlled by adjusting the spinning amount of the upper cover and the shell; an inner layer structure of the vibration isolator comprises an acceleration sensor, an outer transverse groove spring, an inner transverse groove spring and a piezoelectric actuator, the outer transverse groove spring is used for buffering longitudinal rigid impact, the acceleration sensor is used for detecting vibration signals and providing feedback for active control of the vibration isolator, and the piezoelectric actuator is located between the inner transverse groove spring and the outer transverse groove spring. Active control is carried out according to signals of the acceleration sensor, and counter-acting force is generated to counteract vibration. The three-direction rigidity can be adjusted, specifically, rigidity adjustment is achieved in the vertical direction through the transverse groove springs, and rigidity adjustment is achieved in the horizontal direction by changing the filling amount and density of the metal rubber pads.

Description

Technical Field

[0001] This application relates to the field of vibration isolation technology, for example, it relates to an active three-way stiffness adjustable vibration isolator. Background Art

[0002] Vibration isolators play a crucial role in airborne electronic systems. They can effectively attenuate and suppress the vibration, shock, and sway interference received by the system, thereby ensuring the normal operation of electronic devices in a stable environment and preventing performance degradation or damage caused by external excitation. Especially in extreme environments, vibration isolators can significantly reduce the impact of high-intensity shocks on airborne electronic devices and provide crucial protection.

[0003] Passive vibration isolators are favored for their simple structure, long lifespan, and low failure rate. However, they may resonate at certain specific frequencies, resulting in a reduced vibration isolation effect or even enhanced vibration. In addition, under extreme shocks, their elastic elements may fail due to overload. Stiffness adjustable vibration isolators achieve stiffness adjustment by adjusting the spring pre-tightening force or magnetic field strength to adapt to different vibration frequencies and load conditions, thereby improving the vibration isolation effect. However, the system response time of this type of vibration isolator is relatively long, which may limit its application in some rapidly changing environments.

[0004] Active vibration isolators use acceleration sensors, PID closed-loop control systems, and actuators to actively cancel external vibrations, and have the advantages of rapid response, effective suppression of multi-frequency vibrations, and strong vibration isolation effect. However, they have problems such as complex systems and high application costs.

[0005] Currently, although the commonly used modular anti-shock peakless vibration isolators for military airborne electronic devices show certain effects in suppressing resonance and buffering, strong impact forces may cause permanent deformation of their spring sheets and render the dampers ineffective. Therefore, studying the application of active vibration isolators in the military field is of great significance for improving the vibration isolation effect.

[0006] In terms of related patents, the non-resonant peak vibration isolation buffer proposed in Chinese patent document CN109307040B can extend the lifespan of the damping component and avoid jamming, but it only provides vibration reduction in 1 degree of freedom and cannot achieve the vibration reduction effect in 3 degrees of freedom. Although the radial spring type non-resonant peak vibration isolator of CN107165976B has an anti-strong shock vibration isolation effect and a simple structure, it can also only provide damping in two directions and cannot adjust the stiffness to adapt to different load environments. The three-way stiffness adjustable vibration isolator proposed in CN107289054A can achieve lateral stiffness adjustment, but lacks an active control function and cannot completely suppress the resonance peak and the rapid decay of high-frequency vibrations.

[0007] It should be noted that the information disclosed in the above background art section is only used to enhance the understanding of the background of the present application, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0008] To provide a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a comprehensive review, nor is it intended to identify key / important elements or delineate the scope of protection of these embodiments. Instead, it serves as a prelude to the detailed description that follows.

[0009] Embodiments of the present disclosure provide an active three-way stiffness adjustable vibration isolator, which combines the characteristics of a stiffness adjustable type and an active vibration isolator to design an active three-way stiffness adjustable vibration isolator. This new type of vibration isolator not only has better anti-impact performance and shorter stabilization time, but also has better vibration isolation ability, providing a higher level of protection for airborne electronic equipment.

[0010] In some embodiments, the active three-way stiffness adjustable vibration isolator includes an outer structure and an inner structure.

[0011] The outer structure includes an upper cover, a housing, and a buffer assembly. The buffer assembly is connected to the housing. The buffer assembly includes a metal rubber pad. The upper cover is threadedly connected to the housing. By adjusting the rotation amount of the upper cover and the housing, the density of the metal rubber pad is controlled to adjust the stiffness in the horizontal direction.

[0012] The inner structure includes an acceleration sensor, an outer cross-slot spring, an inner cross-slot spring, and a piezoelectric actuator. The outer cross-slot spring is used to buffer longitudinal rigid impacts. The acceleration sensor is used to detect vibration signals and provide feedback for the active control of the vibration isolator. The piezoelectric actuator is located between the inner cross-slot spring and the outer cross-slot spring and performs active control according to the signal of the acceleration sensor to generate a reaction force to offset the vibration.

[0013] Optionally, the outer structure further includes:

[0014] A base, connected to the bottom of the housing. The base has a protruding limiting ring, and the inner diameter of the ring is the same as the outer diameter of the inner cross-slot spring;

[0015] The inner cross-slot spring is installed inside the limiting ring, and the outer cross-slot spring is installed outside the limiting ring.

[0016] Optionally, the upper cover is a cylindrical structure and is connected to the housing by threads;

[0017] The metal rubber pad is installed at the top inside the housing and cooperates with the upper cover;

[0018] The housing is of an inverted T-shaped structure, with threads on the outer side of the top, which can be connected to the upper cover through threads. There are threads on the inner side of the bottom of the housing, which can be connected to the base. A square groove is reserved at the bottom of the housing for passing the circuit of the piezoelectric actuator.

[0019] Optionally, the inner layer structure further includes:

[0020] A hexagonal ring, located at the top of the inner layer, for fixing and installing the acceleration sensor;

[0021] Adjusting bolts and adjusting bolt interfaces for adjusting the pre-tightening force of the inner transverse groove spring and the outer transverse groove spring, thereby changing the stiffness of the vibration isolator;

[0022] An upper spring seat, located below the adjusting bolt interface, for supporting the outer transverse groove spring;

[0023] A cap, internally connected to the adjusting bolt and externally connected to the metal rubber pad. The adjusting bolt, adjusting bolt interface, upper spring seat, outer transverse groove spring, piezoelectric actuator and inner transverse groove spring are located inside the cap. The cap is connected to the upper spring seat through a positioning pin.

[0024] Optionally, inside the outer transverse groove spring are the adjusting bolt interface, upper spring seat, piezoelectric actuator and inner transverse groove spring;

[0025] Outside the outer transverse groove spring are the buffer assembly and the housing.

[0026] Optionally, on the upper side of the inner transverse groove spring is a threaded metal plate, which can be connected to the lower end of the piezoelectric actuator through bolts.

[0027] Optionally, the adjusting bolt interface is of an inverted T-shaped structure. The lower end can be threadedly mated with the upper end of the piezoelectric actuator to limit and adjust the piezoelectric actuator and the inner transverse groove spring; the upper end is connected to the airborne equipment cabinet through threads.

[0028] Optionally, the upper spring seat is of a T-shaped structure. The lower side is a cylindrical structure, and the upper side is a circular or circular ring steel plate. The outer diameter of the cylinder is the same as the inner diameter of the outer transverse groove spring and is inserted into the outer transverse groove spring during installation; there are threads inside the cylinder, which can be threadedly connected to the adjusting bolt. The steel plate is annularly arranged with four bolt holes and can be bolted to the outer transverse groove spring; there are threaded holes on the side of the circular steel plate, which can be bolted to the threaded holes on the side of the adjusting bolt to play a limiting role.

[0029] Optionally, the adjusting bolt has a cross-shaped structure. The upper end of the adjusting bolt is a hexagonal nut, which is connected to the hexagonal ring to limit the rotation of the hexagonal ring. The middle of the adjusting bolt is a boss structure to limit the cap. The lower end is a cylindrical structure with internal threads, which can be connected to the external threads on the upper spring seat. There is a threaded hole on the inner wall of the cylinder, which can be connected to the threaded hole on the side of the upper spring seat through a bolt to play a height-limiting role.

[0030] Optionally, the front end of the hexagonal ring is sleeved on the upper end of the adjusting bolt, and the end is connected to the acceleration sensor through a bolt. At the same time, the hexagonal ring can be used as a wrench.

[0031] The active three-way stiffness adjustable vibration isolator provided by the embodiments of the present disclosure can achieve the following technical effects:

[0032] This application proposes an active three-way stiffness adjustable vibration isolator. By introducing active vibration isolation, the low-frequency vibration isolation performance is further improved compared with the passive one, and the high-frequency vibration isolation performance does not decay, so as to achieve efficient vibration reduction in a wide frequency band; the anti-shock performance is better and it stabilizes faster.

[0033] This application proposes an active three-way stiffness adjustable vibration isolator with adjustable three-way stiffness. Specifically: the stiffness is adjusted in the vertical direction through the transverse groove spring, and the stiffness is adjusted in the horizontal direction by changing the filling amount and density of the metal rubber pad, and the density of the metal rubber pad is adjusted by changing the screw rotation amount between the upper cover and the outer shell.

[0034] Compared with ordinary helical springs, the transverse groove spring used in the active three-way stiffness adjustable vibration isolator proposed by the invention is easier to carry out parametric design. Through the design of structural parameters, the accurate control of stiffness is realized, and then the design of the natural frequency is conveniently realized.

[0035] The piezoelectric actuator used in the active three-way stiffness adjustable vibration isolator proposed by this application has the advantages of high-frequency response, large output force, small volume, etc. It can meet the size limitation of the vibration isolator for airborne electronic equipment, and can provide sufficient active control force, so as to achieve wide-frequency and efficient vibration isolation.

[0036] It should be noted that piezoelectric materials are brittle materials with high stiffness and small stroke, and they cannot resist strong impact. The active three-way stiffness adjustable vibration isolator proposed by this application realizes the reduction of the overall stiffness by connecting the piezoelectric actuator in series with the inner transverse groove spring, and ensures sufficient displacement to play a role in buffering and anti-shock, thereby preventing the damage of the piezoelectric actuator.

[0037] The active three-way stiffness adjustable vibration isolator consists of a passive vibration suppression part and an active vibration suppression part. The passive vibration suppression part plays a role in supporting and passively reducing vibration for the active three-way stiffness adjustable vibration isolator. The active vibration suppression part plays a role in actively suppressing vibration, improving the vibration reduction performance, and enhancing the response speed.

[0038] Active vibration suppression is mainly composed of a piezoelectric actuator, an inner transverse groove spring, an acceleration sensor, and a control system. The acceleration sensor collects feedforward and feedback signals and sends the signals to the control system. The control system drives the piezoelectric actuator to actively suppress vibration, and finally realizes active vibration suppression.

[0039] The passive vibration suppression part is mainly composed of an outer transverse groove spring and a metal rubber pad. The outer transverse groove spring provides adjustable stiffness in the vertical direction; the metal rubber pad provides adjustable stiffness in the horizontal direction. Combining the outer transverse groove spring and the metal rubber pad, the passive vibration suppression part finally realizes three-way stiffness adjustment.

[0040] The active three-way stiffness adjustable vibration isolator has an adjustable stiffness function. In the vertical direction, the stiffness is adjusted by applying a pre-tightening force to the transverse groove spring by adjusting the adjustment bolt; in the horizontal direction, the density of the metal rubber pad is adjusted by changing the thread rotation amount between the upper cover and the outer shell, and the filling amount of the metal rubber pad is changed, and finally the stiffness adjustment function of the active three-way stiffness adjustable vibration isolator is realized.

[0041] The above general description and the description in the following text are only exemplary and explanatory, and are not used to limit this application. Description of the Drawings

[0042] One or more embodiments are exemplarily illustrated by the corresponding drawings. These exemplary illustrations and the drawings do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements. The drawings do not constitute a scale limitation, and among them:

[0043] Figure 1 is the overall structure diagram of an active three-way stiffness adjustable vibration isolator of this application;

[0044] Figure 2 is the front view structure schematic diagram of an active three-way stiffness adjustable vibration isolator of this application;

[0045] Figure 3 is the half-sectional structure schematic diagram of an active three-way stiffness adjustable vibration isolator of this application;

[0046] Figure 4 is the assembly explosion schematic diagram of an active three-way stiffness adjustable vibration isolator of this application;

[0047] Figure 5 is the upper cover structure schematic diagram of an active three-way stiffness adjustable vibration isolator of this application;

[0048] Figure 6 Schematic diagram of the housing structure of an active three-way stiffness adjustable vibration isolator for this application;

[0049] Figure 7 Schematic diagram of the base structure of an active three-way stiffness adjustable vibration isolator for this application;

[0050] Figure 8 Schematic diagram of the inner transverse groove spring structure of an active three-way stiffness adjustable vibration isolator for this application;

[0051] Figure 9 Schematic diagram of the piezoelectric actuator structure of an active three-way stiffness adjustable vibration isolator for this application;

[0052] Figure 10 Schematic diagram of the adjustment bolt interface structure of an active three-way stiffness adjustable vibration isolator for this application;

[0053] Figure 11 Schematic diagram of the outer transverse groove spring structure of an active three-way stiffness adjustable vibration isolator for this application;

[0054] Figure 12 Schematic diagram of the upper spring seat structure of an active three-way stiffness adjustable vibration isolator for this application;

[0055] Figure 13 Schematic diagram of the adjustment bolt structure of an active three-way stiffness adjustable vibration isolator for this application;

[0056] Figure 14 Schematic diagram of the cap structure of an active three-way stiffness adjustable vibration isolator for this application;

[0057] Figure 15 Schematic diagram of the hexagonal ring structure of an active three-way stiffness adjustable vibration isolator for this application;

[0058] Figure 16 Schematic diagram of the principle of an active three-way stiffness adjustable vibration isolator for this application;

[0059] Figure 17 Comparison chart of the transmissibility curves of an active three-way stiffness adjustable vibration isolator for this application.

[0060] Among them: 1. Hexagonal ring; 2. Upper cover; 3. Housing; 4. Acceleration sensor; 5. Adjustment bolt; 6. Adjustment bolt interface; 7. Upper spring seat; 8. Cap; 9. Inner transverse groove spring; 10. Rubber pad; 11. Base; 12. Rubber pad; 13. Buffer pad; 14. Outer transverse groove spring; 15. Metal rubber pad; 16. Piezoelectric actuator. Detailed implementation method

[0061] In order to understand the features and technical content of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are only for reference and explanation, and are not used to limit the embodiments of the present disclosure. In the following technical description, for the sake of explanation, numerous details are provided to give a thorough understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other instances, well-known structures and devices may be shown in a simplified manner to simplify the drawings.

[0062] The terms "first", "second", etc. in the embodiments of the present disclosure are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so as to implement the embodiments of the present disclosure described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion.

[0063] In the embodiments of the present disclosure, the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", etc. is based on the orientation or positional relationship shown in the accompanying drawings. These terms are mainly used to better describe the embodiments of the present disclosure and their embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation, or be constructed and operated in a specific orientation. And, in addition to being able to represent an orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. 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.

[0064] In addition, the terms "arranged", "connected", "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 directly connected, or indirectly connected through an intermediate medium, or there can also be internal communication 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 specific circumstances.

[0065] Unless otherwise specified, the term "plurality" means two or more.

[0066] In the embodiments of the present disclosure, the character " / " indicates that the objects before and after are in an "or" relationship. For example, A / B means: A or B.

[0067] The term "and / or" is a description of the associated relationship of an object, indicating that there can be three relationships. For example, A and / or B means: A or B, or, A and B these three relationships.

[0068] It should be noted that, without conflict, the embodiments in the present disclosure and the features in the embodiments may be combined with each other.

[0069] Combined with Figure 1-17 As shown, the embodiments of the present disclosure provide an active three-way stiffness adjustable vibration isolator, the structure of which includes an outer structure and an inner structure.

[0070] The outer structure includes an upper cover 2, a metal rubber pad 15, rubber pads 10, 12, a buffer pad 13, a housing 3 and a base 11; the inner structure includes: a hexagonal ring 1, an acceleration sensor 4, a cap 8, an adjustment bolt 5, an adjustment bolt 5 interface, an upper spring seat 7, an outer transverse groove spring 14, a piezoelectric actuator 16 and an inner transverse groove spring 9; each component is connected to each other by threads.

[0071] Specifically, the outer structure includes an upper cover 2, a metal rubber pad 15, a rubber pad 12, a buffer pad 13, a housing 3 and a base 11 from top to bottom in sequence.

[0072] The upper cover 2 is a cylindrical structure and is connected to the housing 3 by threads. The rotation amount of the upper cover 2 and the housing 3 can control the density of the metal rubber pad 15, thereby realizing the stiffness adjustment of the vibration isolator in the horizontal direction.

[0073] The metal rubber pad 15 is installed at the inner top of the housing 3 and cooperates with the upper cover 2 to play a role in limiting and buffering rigid impacts.

[0074] The rubber pad 12 is located below the metal rubber pad 15 to further provide support and buffering.

[0075] The buffer pad 13 is located below the rubber pad 12 to provide an additional buffering effect.

[0076] The housing 3 is an inverted T-shaped structure, with threads on the outer side of the top, which can be connected to the upper cover 2 by threads; there are threads on the inner side of the bottom, which can be connected to the base 11. There are four through holes at the bottom of the housing 3, which are connected to the airborne equipment by bolts. A square groove is also reserved at the bottom of the housing 3 for passing the circuit of the piezoelectric actuator 16.

[0077] The base 11 is connected to the bottom of the housing 3 through the side threads. There is a slightly protruding limit ring on the base 11, and the inner diameter of the ring is the same as the outer diameter of the inner transverse groove spring 9, which plays a limiting role. There are two groups of through holes arranged circumferentially on the base 11, which can be used to connect to the inner transverse groove spring 9 and the outer transverse groove spring 14 through bolts respectively. Preferably, the outer diameter of the limit ring is the same as the inner diameter of the outer transverse groove spring 14. The inner transverse groove spring 9 is installed inside the limit ring, and the outer transverse groove spring 14 is installed outside the limit ring.

[0078] The inner structure from top to bottom successively includes a hexagonal ring 1, an acceleration sensor 4, a cap 8, an adjusting bolt 5, an adjusting bolt interface 6, an upper spring seat 7, an outer transverse groove spring 14, a piezoelectric actuator 16, and an inner transverse groove spring 9; among them, the inner transverse groove spring 9 and the outer transverse groove spring 14 play roles of limiting, supporting, and buffering rigid impacts.

[0079] The hexagonal ring 1 is located at the top of the inner layer and is used for fixing and installing the acceleration sensor 4.

[0080] The acceleration sensor 4 is used to detect vibration signals and provide feedback for the active control of the vibration isolator.

[0081] The cap 8 is located below the acceleration sensor 4 and plays a protective role.

[0082] The adjusting bolt 5 and the adjusting bolt interface 6 are used to adjust the pre-tightening force of the inner transverse groove spring 9 and the outer transverse groove spring 14, thereby changing the stiffness of the vibration isolator.

[0083] The upper spring seat 7 is located below the adjusting bolt interface 6 and is used to support the outer transverse groove spring 14.

[0084] The outer transverse groove spring 14 is installed between the upper spring seat 7 and the base 11 and plays roles of limiting, supporting, and buffering rigid impacts.

[0085] The piezoelectric actuator 16 is located between the inner transverse groove spring 9 and the outer transverse groove spring 14, and performs active control according to the signal of the acceleration sensor 4, generating a reaction force to cancel vibrations.

[0086] The inner transverse groove spring 9 cooperates with the limiting ring on the base 11 and plays roles of limiting and supporting. There are four bolt holes on the lower side of the inner transverse groove spring 9 for bolt connection with the through holes on the base 11. The upper side of the inner transverse groove spring 9 is a metal plate with threads and can be bolt-connected to the lower end of the piezoelectric actuator. The inner transverse groove spring 9 has functions of supporting, limiting, and providing passive vibration reduction.

[0087] Specifically, as Figure 9 shown, the lower end of the piezoelectric actuator 16 has a threaded hole and can be bolt-connected to the top end of the inner transverse groove spring; the upper end thread can be connected to the adjusting bolt interface; the circuit can be led out through the square groove reserved at the bottom of the housing. The piezoelectric actuator 16 provides active vibration reduction for the active three-way stiffness adjustable vibration isolator by introducing a control signal, and jointly acts with the inner transverse groove spring 9 and the outer transverse groove spring 14 to achieve the suppression and rapid stability of the system resonance peak.

[0088] The adjusting bolt interface 6 is of an inverted T-shaped structure. The lower end can be thread-mated with the upper end thread of the piezoelectric actuator 16 and plays roles of limiting and adjusting the piezoelectric actuator 16 and the inner transverse groove spring 9; the upper end is connected to the airborne equipment cabinet through threads.

[0089] There are four bolt holes on each of the upper and lower sides of the outer transverse groove spring 14. The bolt holes on the lower side are connected to the base through bolts; it has the functions of support, limit, and providing passive vibration damping. Inside the outer transverse groove spring 14 are the upper spring seat 7, piezoelectric actuator 16, and inner transverse groove spring 9 on the adjustment bolt interface 6; outside the outer transverse groove spring 14 are the metal rubber pad 15, rubber pad 12, buffer pad 13, and housing 3.

[0090] The upper spring seat 7 is of a T-shaped structure, with a cylindrical structure on the lower side and a circular steel plate on the upper side. The outer diameter of the cylinder is the same as the inner diameter of the outer transverse groove spring 14 and is inserted into the outer transverse groove spring 14 during installation. There is a thread inside the cylinder, which can be connected to the adjustment bolt through the thread. The steel plate is arranged with four bolt holes in a circular pattern and can be connected to the outer transverse groove spring 14 through bolts; there are threaded holes on the side of the circular steel plate, which can be connected to the threaded holes on the side of the adjustment bolt 5 through bolts, playing a limiting role.

[0091] The adjustment bolt 5 is of a cross-shaped structure. The upper end of the adjustment bolt 5 is a hexagonal nut, which is connected to the hexagonal ring 1 to limit the rotation of the hexagonal ring 1; the middle of the adjustment bolt 5 is a boss structure, which plays a limiting role for the cap 8; the lower end is a cylindrical structure, with a thread inside the cylinder, which can be connected to the outer thread on the outside of the upper spring seat 7, and there is a threaded hole on the inner wall of the cylinder, which can be connected to the threaded hole on the side of the upper spring seat 7 through bolts, playing a height-limiting role.

[0092] The upper end of the cap 8 is of a cylindrical structure and is connected to the middle boss structure of the adjustment bolt 5. The lower end is connected to the metal rubber pad 15, and parts such as the adjustment bolt 5, upper spring seat 7 on the adjustment bolt interface 6, outer transverse groove spring 14, piezoelectric actuator 16, and inner transverse groove spring 9 are wrapped inside the cap. The cap 8 plays the roles of limiting, supporting, protecting, and resisting lateral impact. At the same time, it is connected to the upper spring seat 7 through the positioning pin at the upper end to prevent the outer transverse groove spring 14 from twisting during adjustment and use, thus affecting the vibration isolation effect.

[0093] The front end of the hexagonal ring 1 is sleeved on the upper end of the adjustment bolt 5, and the end is connected to the acceleration sensor 4 through bolts. At the same time, the hexagonal ring 1 can be used as a wrench. When the end of the hexagonal ring 1 is rotated to drive the front-end adjustment bolt 5 to rotate, the bottom of the airborne equipment rack is installed with an active three-way stiffness adjustable vibration isolator provided by the present application.

[0094] When installed on the airborne equipment, due to errors in the rack of the airborne equipment, the threaded installation at the bottom of the rack does not reach the theoretical assembly position during the installation process on the adjustment bolt interface 6.

[0095] The active three-way stiffness adjustable vibration isolator provided by this application has a manual leveling function. The specific leveling process is as follows: Rotating the end of the hexagonal ring 1 drives the front adjusting bolt 5 to rotate. By rotating the adjusting bolt 5, the adjusting bolt interface 5 is driven to rotate, resulting in a radial position change, which drives the cap 8 to have a radial position change to reach the matching position, thus realizing the manual leveling function. It should be noted that since the upper spring seat 7 and the cap 8 are connected by a positioning pin, the cap 8 only has a radial position change without rotation, so as to ensure that the outer transverse groove spring 14 twists during adjustment and use, thus affecting the vibration isolation effect.

[0096] Figure 17 It is a comparison chart of the transmissibility curves of an active three-way stiffness adjustable vibration isolator. Compared with the traditional vibration isolation platform, the passive vibration isolation part of the active three-way stiffness adjustable vibration isolator provided by this application has a lower resonance peak and lower low-frequency characteristics; the active vibration isolation part has a faster response speed. After introducing active vibration isolation, the active three-way stiffness adjustable vibration isolator provided by this application can achieve a shorter stabilization time and better vibration isolation ability.

[0097] The active three-way stiffness adjustable vibration isolator of this application realizes adjustable three-way stiffness through the passive vibration damping effect of the inner transverse groove spring 9 and the outer transverse groove spring 14, and the active control effect of the piezoelectric actuator 16. The adjusting bolt interface is used to limit and adjust the piezoelectric actuator and the inner transverse groove spring to ensure that the resonance peak of the system is less than zero at a specific frequency and quickly reaches a stable state. The upper spring seat is used as a connecting part to ensure the stability and reliability between components.

[0098] The acceleration sensor 4 detects the vibration signal, and the controller controls the piezoelectric actuator 16 to generate a reaction force according to the signal to cancel the vibration. At the same time, by adjusting the adjusting bolt 5, the pre-tightening force of the inner transverse groove spring 9 and the outer transverse groove spring 14 can be changed, thereby adjusting the stiffness of the vibration isolator.

[0099] The active three-way stiffness adjustable vibration isolator provided by this application is a device that realizes a negative resonance peak value of the system at a specific frequency by introducing a piezoelectric actuator 16, and has characteristics such as good vibration isolation effect, strong anti-impact performance, short time to reach the stable state of the system, strong adjustability, strong durability, wide application range, strong generality and interchangeability. The active three-way stiffness adjustable vibration isolator provided by this application can be applied to fields such as military airborne electronic protection. Specifically, this application has the following technical characteristics:

[0100] This application proposes an active three-way stiffness adjustable vibration isolator. By introducing active vibration isolation, the low-frequency vibration isolation performance is further improved compared with the passive one, and the high-frequency vibration isolation performance does not decay, so as to achieve efficient vibration reduction in a wide frequency band; the anti-impact performance is better and it stabilizes faster.

[0101] This application proposes an active three-way stiffness adjustable vibration isolator with three-way stiffness adjustment capabilities. Specifically, the vertical stiffness is adjusted through a transverse groove spring, and the horizontal stiffness is adjusted by changing the filling amount and density of the metal rubber pad 15. Among them, the density of the metal rubber pad 15 is adjusted by changing the screw rotation amount between the upper cover 2 and the outer shell 3.

[0102] Compared with ordinary helical springs, the transverse groove spring used in the active three-way stiffness adjustable vibration isolator proposed in the invention is easier to perform parametric design. Through the design of structural parameters, accurate control of stiffness can be achieved, and thus the design of the natural frequency can be conveniently realized.

[0103] The piezoelectric actuator 16 used in the active three-way stiffness adjustable vibration isolator proposed in this application has the advantages of high-frequency response, large output force, and small volume. It can meet the size limitations of the vibration isolator for airborne electronic equipment while providing sufficient active control force, thereby achieving broadband and efficient vibration isolation.

[0104] It should be noted that piezoelectric materials are brittle materials with high stiffness and small stroke, and they cannot resist strong impact conditions. The active three-way stiffness adjustable vibration isolator proposed in this application reduces the overall stiffness by connecting the piezoelectric actuator 16 in series with the inner transverse groove spring 9, and ensures sufficient displacement to play a role in buffering and anti-impact, thereby preventing damage to the piezoelectric actuator 16.

[0105] The active three-way stiffness adjustable vibration isolator consists of a passive vibration suppression part and an active vibration suppression part. The passive vibration suppression part plays a role in supporting and passive vibration reduction for the active three-way stiffness adjustable vibration isolator. The active vibration suppression part plays a role in actively suppressing vibration, improving the vibration reduction performance, and enhancing the response speed.

[0106] Active vibration suppression is mainly composed of a piezoelectric actuator 16, an inner transverse groove spring 9, an acceleration sensor 4, and a control system. The acceleration sensor 4 collects feedforward and feedback signals and sends the signals to the control system. The control system drives the piezoelectric actuator 16 to actively suppress vibration, and finally realizes active vibration suppression.

[0107] The passive vibration suppression part is mainly composed of an outer transverse groove spring 14 and a metal rubber pad 15. The outer transverse groove spring 14 provides adjustable stiffness in the vertical direction; the metal rubber pad 15 provides adjustable stiffness in the horizontal direction. Combining the outer transverse groove spring 14 and the metal rubber pad 15, the passive vibration suppression part finally realizes three-way stiffness adjustment.

[0108] The active three-way stiffness adjustable vibration isolator has an adjustable stiffness function. In the vertical direction, the stiffness is adjusted by applying a pre-tightening force to the transverse groove spring by adjusting the adjusting bolt 5; in the horizontal direction, the density of the metal rubber pad 15 is adjusted by changing the screw rotation amount between the upper cover 2 and the outer shell 3, and the filling amount of the metal rubber pad 15 is changed, ultimately realizing the stiffness adjustment function of the active three-way stiffness adjustable vibration isolator.

[0109] This application proposes an active three-way stiffness adjustable vibration isolator, which is composed of an upper cover 2, a metal rubber pad 15, rubber pads 12, 10, a buffer pad 13, an outer shell 3, a base 11, a hexagonal ring 1, an acceleration sensor 4, a cap 8, an adjusting bolt 5, an adjusting bolt 5 interface, an upper spring seat 7, an outer transverse groove spring 14, a piezoelectric actuator 16, and an inner transverse groove spring 9.

[0110] The outer shell 3 of the active three-way stiffness adjustable vibration isolator provided by this application has an inverted T-shaped structure, with threads on the outer side of the top, which can be connected to the upper cover 2 through threads; there are threads on the inner side of the bottom, which can be connected to the base 11; there are four through holes at the bottom of the outer shell 3, which are connected to the airborne equipment through bolts; a square groove is reserved at the bottom of the outer shell 3 for the circuit passing through the piezoelectric actuator 16.

[0111] The adjusting bolt 5 interface of the active three-way stiffness adjustable vibration isolator provided by this application has an inverted T-shaped structure. The lower end can be threadedly matched with the upper end of the piezoelectric actuator 16, playing a role in limiting and adjusting the piezoelectric actuator 16 and the inner transverse groove spring 9; the upper end is connected to the airborne equipment cabinet through threads.

[0112] The cap 8 of the active three-way stiffness adjustable vibration isolator provided by this application is connected to the adjusting bolt 5 inside and to the metal rubber pad 15 outside, and wraps the parts such as the adjusting bolt 5, the adjusting bolt 5 interface, the upper spring seat 7, the outer transverse groove spring 14, the piezoelectric actuator 16, and the inner transverse groove spring 9 inside the cap 8. At this time, the cap 8 plays a role in limiting, supporting, protecting, and resisting lateral impact. At the same time, it is connected to the upper spring seat 7 through the positioning pin at the upper end to prevent the outer transverse groove spring 14 from twisting during adjustment and use, thus affecting the vibration isolation effect.

[0113] The front end of the hexagonal ring 1 of the active three-way stiffness adjustable vibration isolator provided by this application is sleeved on the upper end of the adjusting bolt 5, and the end is connected to the acceleration sensor 4 through a bolt. At the same time, the hexagonal ring 1 can be used as a wrench. When the front end adjusting bolt 5 is rotated by driving the end of the hexagonal ring 1, the bottom of the airborne equipment rack is installed with the active three-way stiffness adjustable vibration isolator provided by this application.

[0114] When installed in an airborne device, due to the errors in the frame of the airborne device, the threaded part at the bottom of the frame does not reach the theoretical assembly position during the installation on the interface of the adjusting bolt 5. The active three-way stiffness adjustable vibration isolator provided in this application has a manual leveling function, and the specific leveling process is as follows: Rotate the end of the hexagonal ring 1 to drive the front adjusting bolt 5 to rotate. By rotating the adjusting bolt 5, the interface of the adjusting bolt 5 is driven to rotate, resulting in a radial position change, which drives the cap 8 to have a radial position change to reach the adapted position, thus realizing the manual leveling function. It should be noted that since the upper spring seat 7 and the cap 8 are connected by a positioning pin, the cap 8 only has a radial position change without rotation, thus ensuring that the outer transverse groove spring 14 does not twist during adjustment and use, which may affect the vibration isolation effect.

[0115] The above description and the drawings fully illustrate the embodiments of the present disclosure, enabling those skilled in the art to practice them. Other embodiments may include structural and other changes. Embodiments only represent possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Parts and features of some embodiments may be included in or substituted for parts and features of other embodiments. The embodiments of the present disclosure are not limited to the structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present disclosure is only limited by the appended claims.

Claims

1. An active three-way adjustable stiffness vibration isolator, characterized in that: include: The outer layer structure comprises an upper cover (2), an outer shell (3) and a buffer component, wherein the buffer component is connected to the outer shell, and the buffer component comprises a metal rubber pad (15). The upper cover (2) and the outer shell (3) are threadedly connected, and the density of the metal rubber pad (15) is controlled by adjusting the rotation amount of the upper cover (2) and the outer shell (3) to adjust the rigidity in the horizontal direction; The inner layer structure includes an acceleration sensor (4), an outer transverse groove spring (14), an inner transverse groove spring (9) and a piezoelectric actuator (16). The outer transverse groove spring (14) is used to buffer longitudinal rigid impact. The acceleration sensor (4) is used to detect vibration signals and provide feedback for active control of the vibration isolator. The piezoelectric actuator (16) is located between the inner transverse groove spring (9) and the outer transverse groove spring (14) and performs active control according to the signal of the acceleration sensor (4) to generate a reaction force to offset the vibration.

2. The active three-way adjustable stiffness vibration isolator according to claim 1, characterized in that: The outer structure also includes: A base (11) connected to the bottom of the housing (3), the base (11) having a protruding limiting ring, the inner diameter of the ring being the same as the outer diameter of the inner transverse groove spring (9); The inner transverse groove spring (9) is installed on the inner side of the limiting circular ring, and the outer transverse groove spring (14) is installed on the outer side of the limiting circular ring.

3. The active three-way adjustable stiffness vibration isolator according to claim 2, characterized in that: The upper cover (2) is a cylindrical structure and is connected to the outer shell (3) via threads; The metal rubber pad (15) is installed on the top of the inner side of the housing (3) and cooperates with the upper cover (2); The outer shell (3) is an inverted T-shaped structure, with threads on the outer side of the top, which can be connected to the upper cover (2) through threads; the inner side of the bottom of the outer shell (3) has threads, which can be connected to the base (11); and a square groove is also reserved at the bottom of the outer shell (3) for passing the circuit of the piezoelectric actuator (16).

4. The active three-way adjustable stiffness vibration isolator according to claim 1, 2 or 3, characterized in that: The inner layer structure also includes: A hexagonal ring (1), located at the top of the inner layer, for fixing and mounting the acceleration sensor (4); The adjusting bolt (5) and the adjusting bolt interface (6) are used to adjust the preload force of the inner transverse groove spring (9) and the outer transverse groove spring (14), thereby changing the stiffness of the vibration isolator; An upper spring seat (7) is located below the adjusting bolt interface (6) and is used to support the outer transverse groove spring (14); The cap (8) is connected to the adjusting bolt (5) internally and to the metal rubber pad (15) externally. The adjusting bolt (5), the upper spring seat (7) of the adjusting bolt interface (6), the outer transverse groove spring (14), the piezoelectric actuator (16) and the inner transverse groove spring (9) are located inside the cap (8). The cap (8) is connected to the upper spring seat (7) via a positioning pin.

5. The active three-way adjustable stiffness vibration isolator according to claim 4, characterized in that: The inner side of the outer transverse groove spring (14) is provided with a spring seat (7) on the adjustment bolt interface (6), a piezoelectric actuator (16) and an inner transverse groove spring (9); The outer side of the outer transverse groove spring (14) is a buffer component and a shell (3).

6. The active three-way adjustable stiffness vibration isolator according to claim 4, characterized in that: The upper side of the inner transverse groove spring (9) is a metal plate with threads, which can be connected to the lower end of the piezoelectric actuator through bolts.

7. The active three-way adjustable stiffness vibration isolator according to claim 6, characterized in that: The adjusting bolt interface (6) is an inverted T-shaped structure, the lower end of which can be threadedly matched with the upper end of the piezoelectric actuator (16) to limit and adjust the piezoelectric actuator (16) and the inner transverse groove spring (9); the upper end is connected to the airborne equipment cabinet via threads.

8. The active three-way adjustable stiffness vibration isolator according to claim 6, characterized in that: The upper spring seat (7) is a T-shaped structure, the lower side is a cylindrical structure, and the upper side is a circular or annular steel plate. The outer diameter of the cylinder is the same as the inner diameter of the outer transverse groove spring (14), and is inserted into the outer transverse groove spring (14) during installation; the inner side of the cylinder has threads, which can be connected to the adjusting bolt through threads; the steel plate has four bolt holes arranged in a ring shape, which can be connected to the outer transverse groove spring (14) through bolts; the side of the circular steel plate has threaded holes, which can be connected to the threaded holes on the side of the adjusting bolt (5) through bolts, thereby playing a limiting role.

9. The active three-way adjustable stiffness vibration isolator according to claim 6, characterized in that: The adjusting bolt (5) is a cross-shaped structure. The upper end of the adjusting bolt (5) is a hexagonal nut connected to the hexagonal ring (1) for limiting the rotation of the hexagonal ring (1). The middle of the adjusting bolt (5) is a boss structure for limiting the position of the cap (8). The lower end is a cylindrical structure with threads inside the cylinder for connecting with threads on the outer side of the upper spring seat (7). There is also a threaded hole on the inner wall of the cylinder for connecting with the threaded hole on the side of the upper spring seat (7) through a bolt, for limiting the height.

10. The active three-way adjustable stiffness vibration isolator according to claim 6, characterized in that: The front end of the hexagonal ring (1) is inserted into the upper end of the adjusting bolt (5), and the rear end is connected to the acceleration sensor (4) through a bolt. At the same time, the hexagonal ring (1) can be used as a wrench.

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