High-buffering transverse-vertical coupling anti-impact vibration isolation platform

Abstract

The invention discloses a horizontal-vertical coupling anti-impact vibration isolation platform for high buffering. The horizontal-vertical coupling anti-impact vibration isolation platform comprises an equipment mounting platform, an air spring buffering system, an auxiliary supporting system and a mounting base. The equipment mounting platform comprises an upper mounting base surface which can be freely customized and a lower mounting base surface which is used for connecting the auxiliary supporting system and the vertical air bag unit; the air bag buffering system comprises a vertical buffering air bag set and a transverse buffering air bag set. The auxiliary supporting system comprises a supporting ridge and a square foundation pillar; the installation base comprises a lower installation base face used for being connected with the ground and an upper installation base face used for being connected with and installing the auxiliary supporting system. According to the high-buffering transverse-vertical coupling anti-impact vibration isolation platform, impact and vibration from different directions can be efficiently isolated, and the anti-impact capacity of an equipment structure is remarkably improved. The internal air bag system can rapidly respond and absorb exciting force, damage to equipment or a structure is reduced, meanwhile, an excellent vibration reduction effect is provided, and the stability and safety of an equipment system are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of impact-resistant and buffering vibration-isolating structures, in particular to a highly buffered transverse-vertical coupling impact-resistant vibration-isolating platform. Background Art

[0002] With the rapid development of science and technology, more and more electronic equipment and instruments are applied to related fields. Due to their high accuracy, easy operation and intelligent judgment, they have become an indispensable part of ships. Studies have shown that when an explosion occurs, the most serious impact on ships is the failure of electronic control systems, radar systems, communication and navigation equipment, engines and other shipboard equipment caused by transient loads. Damage to these devices may not only lead to the loss of key system functions, but also trigger a chain reaction, causing more serious damage.

[0003] During the impact test, a variety of precision test instruments need to be installed inside the platform, including various sensors, computers and other precision equipment. Most of these devices are ordinary equipment and have no impact resistance. In order to ensure that various sensors and test equipment work normally and save data during underwater explosions, these devices must be protected from impact. The buffer platform is a buffer device composed of impact isolation elements and a support frame. The measuring equipment is installed on this device. During the underwater explosion, the impact response of the platform is used as the impact input of the buffer platform. After the buffer isolation effect of the buffer platform, the system frequency can be reduced and the impact of the impact on the measuring equipment can be reduced. When designing the buffer platform, the primary principle is to ensure its own strength and rigidity, and to provide a safe impact environment for the test instrument under the impact of the explosion.

[0004] Therefore, designing a buffer platform that can effectively provide anti-impact protection is of great significance to ensure the reliability and survivability of these shipborne equipment under extreme conditions. This buffer platform needs to be able to cope with high-intensity multi-directional coupled transient impacts, which is a huge challenge in the current design of anti-impact platforms for shipborne equipment. Existing anti-impact platforms for shipborne equipment usually adopt the method of overall or partial fixation, and vertical connection support with buffer units. Although it can effectively cope with regular small-intensity impacts in one direction, such as vibration during equipment operation, impact of waves transmitted from the hull to the equipment during ship navigation, and small-intensity transient impacts, when facing the explosion impact of the ship when it is attacked and the motion impact generated when the ship performs high-intensity maneuvers, these impacts have the characteristics of large amplitude, narrow pulse width, non-fixed and non-single direction, and the protection capability of the existing platform is insufficient. Therefore, the development of a new and highly adaptable buffer platform technology has become an urgent need to improve the reliability and durability of shipborne equipment under extreme conditions. This new type of buffer platform should have the following key characteristics: first, it should be able to effectively absorb and disperse high-intensity transient impact energy from all directions, and have the ability to effectively isolate multi-directional coupled impacts; second, it should have rapid response capabilities and be able to make buffering actions in a very short time to adapt to the dynamic changes of impact loads; third, it should be compact and lightweight to reduce the impact on the overall performance of the ship; fourth, it should be easy to maintain and upgrade, so as to facilitate adaptive adjustments based on the latest threat situation and technological advances.

[0005] This new type of buffer platform has multi-directional coupled transient impact protection capabilities, can adapt to complex and changeable impact environments, and can significantly improve the survivability of shipborne equipment. In order to meet the requirements of high-intensity transient impact resistance, the selection of buffer units is very important. Common buffer units used in existing impact-resistant platforms include spring buffer units and hydraulic buffer units. Although the spring buffer unit has a good vibration isolation effect and can withstand a certain radial displacement, the spring itself has a high natural frequency, so it has a poor impact resistance when dealing with sudden loads. It will vibrate for a long time after being subjected to sudden loads; the hydraulic buffer unit cannot withstand radial displacement due to its structure, and may be damaged when subjected to axial loads. Airbag isolators use compressed gas as the working medium and have the advantages of high flexibility, low natural frequency, high controllability and large standard load. They can not only withstand radial displacement, but also effectively respond to sudden loads. Therefore, airbag isolators show significant advantages in dealing with high-intensity transient impacts of shipborne equipment in extreme impact environments.

[0006] Taking all the above factors into consideration, in order to meet the impact resistance requirements of shipborne equipment in complex impact environments, it is a practical need to design a transverse-vertical coupled impact-resistant buffer platform using airbag isolators as buffer units. Summary of the invention

[0007] The purpose of the present invention is to provide a highly buffered transverse-vertical coupling anti-impact vibration isolation platform.

[0008] A highly buffered transverse-vertical coupled anti-impact vibration isolation platform comprises an equipment mounting platform, an airbag buffer system, an auxiliary support system and a mounting base; the auxiliary support system comprises a square base column and a support ridge; the airbag buffer system comprises a longitudinal buffer airbag group and a transverse buffer airbag group; the lower mounting base surface of the equipment mounting platform is connected to the longitudinal buffer airbag group and the support ridge; the upper mounting base surface of the mounting base is connected to the square base column and the support ridge; the longitudinal buffer airbag group is connected to the square base column; and the support ridges of the two mounting base surfaces are connected via a transverse buffer airbag group.

[0009] Furthermore, the natural frequency of the airbag, the output acceleration of the equipment installation table, and the maximum force that the platform can input satisfy:

[0010] Airbag output natural frequency:

[0011] Output acceleration of equipment installation table: G out =2πf nR ΔV≤80g

[0012] The maximum force that the platform can input:

[0013] Where n is the number of vertically / laterally installed airbags, k is the stiffness of a single installed airbag, m1 is the mass of the vibration isolation platform, and m2 is the mass of a single installed airbag. It is the acceleration input of arbitrary waveform.

[0014] Furthermore, the installation base surface under the equipment installation platform contains 4 installation positions on each side, with a total of 12 installation positions, of which the installation positions at the 4 corners are used to connect the longitudinal buffer airbag group, and the 2 installation positions in the middle of each side are used to install the supporting ridges connecting the transverse buffer airbag group.

[0015] Furthermore, a square base is installed at each corner of the upper mounting base surface of the mounting base for connecting the longitudinal buffer airbag group; and a mounting position is set in the middle of each side for installing a supporting ridge connecting the transverse buffer airbag group.

[0016] Furthermore, the longitudinal buffer airbag group has a total of 4 airbag units, which are installed at the 4 corners of the buffer, one at each corner, and connected to the lower mounting base of the equipment mounting platform and the square base column on the mounting base; the transverse buffer airbag group has a total of 8 airbag units, which are installed on the 4 sides of the buffer, 2 on each side, and connected to the lower mounting base surface of the equipment mounting platform and the upper mounting base surface of the mounting base through a supporting ridge.

[0017] Furthermore, the airbag cushioning unit is composed of n airbags connected in series.

[0018] Furthermore, the support ridge is formed by vertically welding two pieces of high-strength steel, with mounting holes left thereon, and with two ribs on each side for reinforcement.

[0019] The beneficial effects of the present invention are:

[0020] A horizontal-vertical coupling anti-shock method is provided. During the experimental verification phase, it is found that compared with traditional anti-shock technology, this method only needs to use fewer anti-shock units to achieve the same or even better buffering effect. This method enables the equipment to adapt to various impact environments and conditions, providing new directions and possibilities for the development of anti-shock technology.

[0021] Aiming at the extreme impact environment of ships, a transverse-vertical coupled symmetrical buffer structure is designed in detail. By cleverly combining the buffer mechanisms in the transverse and vertical directions, it can achieve more efficient energy absorption and dispersion when facing non-unidirectional coupled impacts, and provide shipborne equipment with buffering and impact protection against multi-directional transient impacts. It can effectively cope with the complex loading conditions of the equipment carried by the buffering and impact-resistant structure in the actual working environment of the shipborne equipment.

[0022] Airbag buffer technology is used. This airbag has the characteristics of small size, no creep, and strong load-bearing capacity. Compared with traditional spring buffer units, airbag buffers have shown significant advantages in absorbing impact energy and have good buffering effects on high-intensity transient impacts in the impact environment of shipborne equipment. Considering the advantage of the small size of the airbag buffer, an airbag buffer unit consisting of three airbag buffers in series is designed. This design not only improves the safety of the equipment in extreme situations, but also reduces the maintenance cost in the event of accidental damage. Through the series design, each airbag buffer can absorb the impact energy in stages, which can reduce the load on a single buffer, thereby improving the stability and reliability of the entire system.

[0023] The invention has a simple structure, is easy to install, and has good versatility for various shipborne equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of a highly buffered transverse-vertical coupling anti-impact vibration isolation platform of the present invention;

[0025] Figure 2 It is a general schematic diagram of a highly buffered horizontal-vertical coupled anti-impact vibration isolation platform of the present invention;

[0026] Figure 3It is a schematic diagram of a mounting base of a highly buffered horizontal-vertical coupled anti-impact vibration isolation platform and an auxiliary support system of the connected parts of the present invention;

[0027] Figure 4 It is a schematic diagram of an equipment installation platform of a highly buffered horizontal-vertical coupled anti-impact vibration isolation platform of the present invention and an auxiliary support system of the connected parts;

[0028] Figure 5 It is a schematic structural diagram of a support ridge of a highly buffered horizontal-vertical coupling anti-impact vibration isolation platform of the present invention;

[0029] Figure 6 It is a structural schematic diagram of a square base column of a highly buffered horizontal-vertical coupling anti-impact vibration isolation platform of the present invention;

[0030] Figure 7 It is the acceleration output of different measuring points on the buffer platform surface of a high-buffered horizontal-vertical coupling anti-impact vibration isolation platform of the present invention;

[0031] Figure 8 The calculation result of the X-direction response of the table feature point of a high-buffered horizontal-vertical coupling anti-shock vibration isolation platform of the present invention;

[0032] Fig. 9 The calculation result of the Y-direction response of the table feature point of a high-buffered horizontal-vertical coupling anti-shock vibration isolation platform of the present invention;

[0033] Fig.10 The calculation result of the Z-direction response of the table feature point of a high-buffered horizontal-vertical coupling anti-impact vibration isolation platform of the present invention;

[0034] Description of reference numerals:

[0035] 1-Equipment installation platform, 2-Air spring buffer system, 3-Square base column, 4-Support ridge, 5-Installation base DETAILED DESCRIPTION

[0036] The present invention is further described below in conjunction with the accompanying drawings.

[0037] In order to fully express the purpose, technical solutions and advantages of the embodiments of the present invention, the present invention will be described in full and clearly in conjunction with the drawings of the invention examples. Obviously, the embodiments described below are part of the embodiments of the present invention, but not all complete embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] When a ship is attacked by underwater explosions, the base of the installed equipment is subjected to transient impact loads. When the impact duration τ is longer than the natural period T of the vibration isolation systemn When the shock wave is much smaller, the impact of the shock wave shape on the shock response of the device can be ignored, and the decisive factor is the area contained in the waveform. In the waveform represented by acceleration, the same area means the same speed at the end of the shock. This process of jumping speed change, which ignores the shape of the shock wave and uses the speed at the end of the shock to represent the size of the shock, is called a speed step. Its value ΔV is called the step speed, which is mathematically called the starting speed. For the acceleration input of an arbitrary waveform

[0039]

[0040] At present, many domestic standards use this as the impact design value. At this time, the effect of damping on explosion impact can be ignored. Maximum displacement of the equipment:

[0041]

[0042] Maximum device acceleration:

[0043]

[0044] Maximum force acting on the equipment:

[0045]

[0046] Where: K z ——Impact stiffness of vibration isolation system.

[0047] It can be seen from formula (4) that, if the force acting on the equipment is to be reduced when the step speed and the equipment mass remain unchanged, a vibration isolator with the smallest impact stiffness possible should be selected.

[0048] like Figure 1 is a typical impact acceleration input curve with a peak value of 3000g. From equation (1), it can be calculated that the step velocity ΔV of this waveform is 5m / s.

[0049] Therefore, the natural frequency f of the vibration isolator can be estimated n for:

[0050]

[0051] In formula (5), G out The maximum output acceleration. The US MIL-S-901D standard stipulates that when the bottom of the buffer platform is impacted by 3000g acceleration, the acceleration output response of the table top is required to be less than 80g. Therefore, the design requirement of this buffer platform is 80g according to the US MIL-S-901D standard.

[0052] On the existing floating impact platform, the buffer element basically adopts an air spring. This vibration isolator preferably uses an FT75-20 DI CR type three-chamber air spring vibration isolator. Its main performance parameters are as follows: the selected spring has a height of 260 cm, a pressure of 6 bar, a force of 4 kN, a volume of 3.2 I, a natural frequency of 2.1 Hz, a single unit weight of 1.8 kg, and the air spring stiffness parameters are shown in Table 1

[0053] Table 1 Air spring stiffness parameters

[0054]

[0055] The entire set of equipment is 1000 kg according to the medium-sized floating impact platform test standard

[0056] Based on the above conditions, calculate the number of air springs

[0057] Output natural frequency

[0058]

[0059] Output acceleration

[0060] G out = 2πf nR ΔV ≤ 80g

[0061] From this, we get 0 < n ≤ 15. Considering the lightweight of the hull structure and space utilization, at least one vibration isolator is installed on each side. Therefore, 4 FT75-20 DI CR type three-chamber air spring vibration isolators are selected in the vertical and horizontal positions respectively. From this, the actual vertical natural frequency of the vibration isolation system can be calculated:

[0062]

[0063] The actual vertical acceleration acting on the instruments on the buffer platform

[0064] G out垂 = 2πf nR ΔV = 39.9g ≤ 80g (8)

[0065] Actual horizontal natural frequency

[0066]

[0067] The actual horizontal acceleration acting on the instruments on the buffer platform:

[0068] G out横 = 2πf nR ΔV = 39.9g ≤ 80g (10)

[0069] Through the above calculation analysis and verification, it can be known that four FT75-20 DICR three-bag air spring isolators are arranged in the vertical position and the lateral position respectively, and the design of the buffer device meets the technical requirements.

[0070] In practical applications, the air spring model is usually selected according to the design requirements. For example, if the external load impact acceleration is known to be 3000g, the step velocity of 5m / s can be calculated by formula (1). Referring to relevant standards, according to actual use requirements, the output impact velocity of the vibration isolation platform should be reduced to 39.9g, so the actual lateral / vertical natural frequency is calculated to be 12.7Hz by formula (10). On the basis of the known selection of 4 air spring isolators in the vertical and lateral positions of the buffer vibration isolation platform, according to actual needs, the spring stiffness k and weight m are calculated by formula (6), and the optimal value is selected by comprehensively considering the lightweight structure and space utilization of the buffer platform. In this example, k = 1.6*106N / m, m = 1.8kg.

[0071] like Figure 7 As shown in the figure, vertical acceleration input is used as an example to conduct numerical simulation analysis to examine whether the buffering performance of the buffer platform can meet the design requirements. Through the transient response finite element analysis module, vertical acceleration input is applied to the bottom surface of the support seat, making its peak value reach 3000g, and the acceleration output of different measuring points on the buffer platform surface is examined.

[0072] Figures 8 to 10 The acceleration response curves of the three directions of the six characteristic points of the table are the acceleration input in the X direction. It can be seen from the results that the acceleration response order of the characteristic points of the table in the X direction is significantly higher than that in the other two directions. Therefore, the acceleration output curve in the X direction is analyzed: the peak acceleration of the table is about 30g. At the beginning of the impact, the acceleration response of the table reaches the first peak at 200ms. In the subsequent buffering cycle, the acceleration amplitude shows an upward trend again at about 360ms, and another maximum value appears at 500ms. This is because at the end of the first buffering cycle, the buffer platform reaches the compression limit, and the basic vibration will give the test equipment a reaction force, which acts on the buffer platform again and is transmitted to the test equipment. The amplitude at this time is already smaller than the amplitude of the first vibration cycle. Several extreme values ​​will also appear in the vibration cycle after this, but they are significantly smaller than the first two vibration amplitudes. The buffer platform gradually oscillates and then tends to be stable. The acceleration output of the buffer platform in the X direction is no more than 30g, which is less than the 80g specified in the US MIL-S-901D standard, thus verifying the rationality of the buffer platform design.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly buffered horizontal-vertical coupling anti-impact vibration isolation platform, characterized by: The invention comprises an equipment installation platform (1), an airbag cushioning system, an auxiliary support system and an installation base (5); the auxiliary support system comprises a square base column (3) and a support ridge (4); the airbag cushioning system comprises a longitudinal cushioning airbag group and a transverse cushioning airbag group; the lower installation base surface of the equipment installation platform is connected to the longitudinal cushioning airbag group and the support ridge (4); the upper installation base surface of the installation base (5) is connected to the square base column (3) and the support ridge (4); the longitudinal cushioning airbag group is connected to the square base column (3); and the support ridges (4) of the two installation base surfaces are connected via the transverse cushioning airbag group.

2. According to claim 1, a highly buffered lateral-vertical coupling anti-shock vibration isolation platform is characterized by: The natural frequency of the airbag, the output acceleration of the equipment installation table, and the maximum force that the platform can input meet the following requirements: Airbag output natural frequency: Output acceleration of equipment installation table: G out =2πf nR ΔV≤80g The maximum force that the platform can input: Where n is the number of vertically / laterally installed airbags, k is the stiffness of a single installed airbag, m1 is the mass of the vibration isolation platform, and m2 is the mass of a single installed airbag. It is the acceleration input of arbitrary waveform.

3. According to claim 1, a highly buffered lateral-vertical coupling anti-shock vibration isolation platform is characterized in that: The mounting base surface below the equipment mounting platform (1) has 4 mounting positions on each side, for a total of 12 mounting positions, wherein the mounting positions at the 4 corners are used to connect the longitudinal buffer airbag group, and the 2 mounting positions in the middle of each side are used to install the support ridge (4) connecting the transverse buffer airbag group.

4. The high-buffered lateral-vertical coupling anti-shock vibration isolation platform according to claim 1 is characterized by: The upper mounting surface of the mounting base (5) is provided with a square base (3) at each corner for connecting the longitudinal buffer airbag group; and a mounting position is provided in the middle of each side for installing a support ridge (4) for connecting the transverse buffer airbag group.

5. The high-buffered transverse-vertical coupling anti-shock vibration isolation platform according to claim 1 is characterized by: The longitudinal buffer airbag group comprises a total of 4 airbag units, which are respectively installed at the 4 corners of the buffer, with 1 airbag unit at each corner, and connected to the lower mounting base of the equipment mounting platform (1) and the square base column (3) on the mounting base (5); the transverse buffer airbag group comprises a total of 8 airbag units, which are installed at the 4 sides of the buffer, with 2 airbag units at each side, and connected to the lower mounting base surface of the equipment mounting platform (1) and the upper mounting base surface of the mounting base (5) through the support ridge (4).

6. A highly buffered transverse-vertical coupling anti-shock vibration isolation platform according to claim 4, characterized in that: The airbag cushioning unit is composed of n airbags connected in series.

7. The high-buffered transverse-vertical coupling anti-shock vibration isolation platform according to claim 1 is characterized by: The support ridge (4) is composed of two pieces of high-strength steel welded vertically, with mounting holes left on it and two ribs on each side for reinforcement.

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