Embedded vibration isolator for truss

Abstract

The invention provides an embedded vibration isolator for a truss. The embedded vibration isolator comprises a flexible hinge, an outer connecting sleeve, an inner sleeve, a pre-tightening spring, a supporting plate, a main corrugated pipe, an auxiliary corrugated pipe, an upper damping cylinder, a lower damping cylinder, a sealing screw, a sealing gasket and a locking block. Wherein the flexible hinge provides axial connection rigidity on one hand and releases radial rotation rigidity on the other hand; a damping cavity formed by the main corrugated pipe, the auxiliary corrugated pipe, the upper damping cylinder, the lower damping cylinder, the sealing screw and the sealing gasket provides a damping effect for the embedded vibration isolator. The embedded vibration isolator for the truss can adapt to installation of truss systems of different configurations, controls vibration of the truss, and has the advantages of being convenient to install and replace, reliable, safe and the like.

Description

Technical Field

[0001] The present invention belongs to the field of vibration control, and particularly relates to an embedded vibration isolator for a truss. Background Art

[0002] Due to the characteristics of lightweight, high load-bearing capacity, foldability, etc., the truss structure has gradually been widely used in spacecraft, especially for the support of payloads and in grid load-bearing cylinders.

[0003] For a spacecraft, micro-vibrations will be transmitted through the truss structure. The truss structure is an essential link in the transmission path. After being transmitted through the truss, the micro-vibrations will be transmitted to the sensitive components installed on it. In order to better suppress the response of micro-vibrations transmitted to the sensitive components, taking micro-vibration suppression measures in the truss is a common and effective means.

[0004] The existing related technical achievements are mainly as follows:

[0005] (1) An active vibration suppression system and method for a flexible truss structure based on piezoelectric materials (patent document CN104092403A), which discloses an active vibration suppression system and method for a flexible truss structure based on piezoelectric materials; realizing active vibration suppression of the flexible truss structure through a piezoelectric stack and a diamond displacement amplification mechanism.

[0006] (2) A viscoelastic damping truss vibration isolator (patent document CN104879414A), which discloses a viscoelastic damping truss vibration isolator, ensuring the relative displacement limitation of the inner cylinder and the outer cylinder through a limit bolt to achieve damping truss support and vibration isolation; buffering through the deformation of the spring and the damping rubber layer. However, the viscoelastic damping effect is not only greatly affected by the vibration frequency but also easily affected by temperature, resulting in a reduction in damping performance, which is not conducive to application in extreme space environments.

[0007] (3) A viscoelastic damping truss vibration isolator (patent document CN202301730U), which also has the technical defect that the viscoelastic damping effect is not only greatly affected by the vibration frequency but also easily affected by temperature, resulting in a reduction in damping performance, which is not conducive to application in extreme space environments.

[0008] (4) A truss-type floating raft vibration isolation device (patent document CN102338190A), which discloses a truss-type floating raft vibration isolation device.

[0009] (5) A semi-active particle damping vibration reduction device for a truss structure (patent document CN102619293A), which discloses a semi-active particle damping vibration reduction device for a truss structure.

[0010] Patent documents (4) and (5) use particle damping to design a vibration damping device for a truss structure. However, due to the disadvantages of particle damping such as poor damping accuracy, easy wear, poor adaptability to high-temperature environments, and easy pollution, its application in space trusses is limited.

[0011] (6) The relevant references are as follows:

[0012] 1. Cao Yuyan, Wang Zhichen, Fu Shixin, et al. Optimal vibration control of intelligent truss structures and optimization of actuator configuration [J]. Journal of Vibration and Shock, 2015, (05): 26-32.

[0013] 2. PREUMONT A, VOLTAN M, SANGIOVANNI A, et al. Active tendon control of suspension bridges [J]. Smart Struct. Syst, 2016, 18(1): 31-52.

[0014] 3. Zou Yuanjie, Ge Dongming, Liu Shaokui, et al. Vibration control scheme for large antennas of spacecraft and its experimental verification [J]. Spacecraft Engineering, 2018, 27(03): 135-139.

[0015] The above references respectively use actuators such as piezoelectric rods and guy wires, and combine active control algorithms to suppress the vibration of the truss structure. The above vibration suppression methods of series-connected active actuators in the truss structure all require complex hardware circuit systems, consume external energy, and have low system reliability. Once they diverge, they may cause irreparable failures.

[0016] In summary, the methods for vibration control of truss structures in the prior art mainly include active embedded actuator control, viscoelastic damping control, and particle damping friction control. The existing vibration control methods for truss structures have the following deficiencies in engineering applications:

[0017] (1) Active embedded actuator control requires a large amount of external energy, and is likely to cause the system to fail or even diverge, endangering the completion of space missions.

[0018] (2) Viscoelastic damping and friction damping have poor environmental adaptability and are easily affected by temperature, vibration frequency, etc. on the vibration control performance.

[0019] (3) The reduction of the performance of the vibration isolator caused by extrusion and stretching actions during the disassembly and assembly of complex trusses is not considered.

[0020] (6) It is inconvenient to conduct comparative tests before and after the installation of passive vibration isolators in the truss.

[0021] In view of the technical problems existing in the prior art, the present invention provides an embedded vibration isolator for a truss. Summary of the Invention

[0022] In view of the deficiencies in the prior art, the object of the present invention is to provide an embedded vibration isolator for a truss.

[0023] An embedded vibration isolator for a truss according to the present invention includes: a flexible hinge 2, an outer connecting sleeve 4, an inner sleeve 6, a locking block 3, and a damping cavity 16;

[0024] One end of the flexible hinge 2 is provided with an external interface, and the other end is connected to the outer connecting sleeve 4;

[0025] The locking block 3 is installed on the flexible hinge 2;

[0026] The damping cavity 16 is respectively connected to the outer connecting sleeve 4 and the inner sleeve 6.

[0027] Preferably, one end of the flexible hinge 2 connected to the locking block 3 is provided with a plurality of hollow arc-shaped grooves;

[0028] The locking block 3 is arranged in cooperation with the outer periphery of the lower end of the flexible hinge 2.

[0029] Preferably, the radial stiffness of the flexible hinge 2 is greater than the axial stiffness.

[0030] Preferably, the damping cavity 16 includes: an upper damping cylinder 10, a lower damping cylinder 12, a sealing screw 14, and a sealing gasket 13;

[0031] The lower damping cylinder 12 is fixedly connected to the outer connecting sleeve 4 by screws,

[0032] The upper damping cylinder 10 is connected to the inner sleeve 6;

[0033] The sealing screw 14 is arranged in the lower damping cylinder 12, and a sealing gasket 13 is interposed therebetween.

[0034] Preferably, the damping cavity 16 further includes: a support plate 8, a main bellows 11, and a secondary bellows 9;

[0035] The support plate 8 is arranged in the inner sleeve 6;

[0036] The lower damping cylinder 12 is a columnar body, and there is a columnar part in the middle section with a larger cylinder diameter than other sections,

[0037] The main bellows 11 is arranged on the outer edge of the columnar part with a smaller cylinder diameter of the lower damping cylinder 12, and is arranged between the upper damping cylinder 10 and the lower damping cylinder 12;

[0038] The secondary bellows 9 is arranged between the upper damping cylinder 10 and the support plate 8.

[0039] Preferably, the damping cavity 16 is filled with damping liquid. Through the relative movement among the upper damping cylinder 10, the lower damping cylinder 12 and the support plate 8, the damping liquid in the main bellows 11 and the auxiliary bellows 9 is extruded, and the damping liquid flows through the central channel of the upper damping cylinder 10. The damping cavity 16 squeezes the internal damping liquid to flow, providing a damping effect for the truss system.

[0040] Preferably, a preloading spring 7 is provided between the inner sleeve 6 and the support plate 8.

[0041] Preferably, the formula for the method of selecting the stiffness coefficient of the preloading spring 7 is:

[0042]

[0043] where ε is the damping coefficient of the damping cavity, ω n is the modal frequency of the truss vibration damping system, v max is the maximum vibration velocity of the truss vibration damping system, and d is the allowable deformation of the spring.

[0044] Preferably, the locking block 3 fixes the elastic displacement of the flexible hinge 2 by screws.

[0045] According to a truss provided by the present invention, the truss uses the embedded vibration isolator for vibration isolation.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. The vibration isolator of the present invention has a compact structure, does not consume external energy, and has an extremely low space occupancy rate;

[0048] 2. The present invention has strong environmental adaptability and has a significant vibration control effect for different high and low temperature environments and different vibration frequencies;

[0049] 3. The present invention ensures that the installation and disassembly do not affect the performance of the vibration isolator through the locking block, simplifying the vibration isolation performance comparison test. Description of the Drawings

[0050] By reading the following detailed description of the non-restrictive embodiments with reference to the accompanying drawings, other features, objects and advantages of the present invention will become more obvious:

[0051] Figure 1 Comparison diagram of installing embedded vibration isolators for different configurations of trusses;

[0052] Figure 2 Schematic diagram of the embedded vibration isolator;

[0053] Figure 3 Schematic diagram of the flexible hinge;

[0054] Figure 4Front elevation schematic view of the embedded vibration isolator;

[0055] Figure 5 is Figure 4 Schematic cross-sectional view along the A-A direction.

[0056] As shown in the figure:

[0057] Specific implementation manners

[0058] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all fall within the protection scope of the present invention.

[0059] Refer to Figures 1 to 5 As shown, an embedded vibration isolator for a truss provided by the present invention includes: a flexible hinge 2, an outer connecting sleeve 4, an inner sleeve 6, a locking block 3, and a damping cavity 16;

[0060] One end of the flexible hinge 2 is connected to the truss 1, and the other end is connected to the outer connecting sleeve 4;

[0061] The locking block 3 is installed on the flexible hinge 2;

[0062] The damping cavity is respectively connected to the outer connecting sleeve 4 and the inner sleeve 6;

[0063] The truss 5 connected to the outer connecting sleeve is connected to the outer connecting sleeve 4.

[0064] The flexible hinge 2 provides the connection stiffness for the entire embedded vibration isolator for the truss; on the one hand, the flexible hinge 2 provides the axial connection stiffness, and on the other hand, it releases the radial rotational stiffness to prevent stress concentration of the vibration isolator;

[0065] One end of the flexible hinge 2 has an external interface connected to the truss 1, and the other end is connected to the outer connecting sleeve 4 to transmit the mechanical response, ensuring the connection stiffness of the embedded vibration isolator for the truss in the truss. The embedded vibration isolator for the truss mainly provides the required stiffness for vibration isolation through the axial deformation of the flexible hinge 2, provides the required damping for vibration isolation by squeezing the damping cavity to make the internal damping liquid flow, and dissipates the vibration energy by using the stiffness damping to do work and generate heat, thereby realizing vibration isolation.

[0066] As Figure 3 shown, one end of the flexible hinge 2 connected to the locking block 3 is provided with a plurality of hollow arc-shaped grooves, so that the flexible hinge 2 is easily deformed under the action of external forces and torques, achieving the effect of vibration isolation;

[0067] The upper end that connects the flexible hinge 2 to the truss 1 is joined with the locking block 3 at the lower end having an arc-shaped hollow groove. The connection stiffness function of the hollow arc-shaped groove is greatly weakened. At this time, the connection stiffness of the entire truss with the embedded vibration isolator is mainly provided by the locking block 3. Since the locking block 3 has a large stiffness and is not easily deformed, the locking function of the truss with the embedded vibration isolator can be realized;

[0068] The locking block 3 is arranged in cooperation with the outer periphery of the lower end of the flexible hinge 2, and the elastic displacement of the flexible hinge 2 is fixed by screws, which is convenient for the installation and replacement of the vibration isolator for the truss of the present invention, and avoids the reduction of the overall vibration isolation performance caused by extrusion and stretching actions. When integrating the truss with the embedded vibration isolator, the performance test comparison of the embedded vibration isolator for the truss is completed through the vibration control test before and after unlocking the locking block 3.

[0069] Furthermore, the radial stiffness of the flexible hinge 2 is much greater than the axial stiffness, and at the same time, the rotational stiffness is extremely small, which can ensure freedom in the rotational direction and realize the function of a small-range universal hinge.

[0070] Furthermore, the damping cavity 16 includes: a support plate 8, a main bellows 11, a sub-bellows 9, an upper damping cylinder 10, a lower damping cylinder 12, a sealing screw 14, and a sealing gasket 13;

[0071] The lower damping cylinder 12 is fixedly connected to the outer connection sleeve 4 by screws;

[0072] The upper damping cylinder 10 is connected to the inner sleeve 6;

[0073] The support plate 8 is arranged in the inner sleeve 6;

[0074] The sealing screw 14 is arranged in the lower damping cylinder 12, and a sealing gasket 13 is padded therebetween;

[0075] The lower damping cylinder 12 is cylindrical, and there is a cylindrical part in the middle section with a larger cylinder diameter than other sections,

[0076] The main bellows 11 is arranged on the outer edge of the column body on the side with a smaller cylinder diameter of the lower damping cylinder 12, and is arranged between the upper damping cylinder 10 and the lower damping cylinder 12;

[0077] The sub-bellows 9 is arranged between the upper damping cylinder 10 and the support plate 8;

[0078] The damping cavity 16 is filled with damping liquid. Through the relative movement among the upper damping cylinder 10, the lower damping cylinder 12, and the support plate 8, the damping liquid in the main bellows 11 and the sub-bellows 9 is squeezed, and the damping liquid flows through the central channel of the upper damping cylinder 10. The damping cavity 16 squeezes the internal damping liquid to flow, thereby providing a damping effect for the truss system and dissipating the vibration energy transmitted to the vibration isolator;

[0079] Furthermore, the flow of the damping liquid within the damping cavity 16 provides the damping effect required by the present invention.

[0080] Specifically, the damping liquid within the damping cavity 16 selects damping liquids with different viscosities according to the position of the vibration source. For the truss near the medium-high frequency vibration source, the embedded vibration isolator selects a damping liquid with a small viscosity coefficient, and for the truss near the low-frequency vibration source, the embedded vibration isolator selects a damping liquid with a large viscosity coefficient.

[0081] In an embodiment of the present invention, the metal material used for the flexible hinge 2 is titanium alloy, and the shape, number, and thickness of the grooved interface of the flexible hinge 2 are flexibly adjusted according to the vibration control requirements of the truss structure.

[0082] The inner sleeve 6 and the support plate 8 axially compress the preload spring 7 disposed therebetween, and the preload spring 7 provides a restoring force for the damping cavity 16 to promote the flow of the damping liquid.

[0083] For the said preload spring 7, the formula for selecting its stiffness coefficient is:

[0084]

[0085] wherein, K is the stiffness coefficient, ε is the damping coefficient of the damping cavity, obtained from the damping hysteresis curve; ω n is the modal frequency of the truss vibration reduction system, obtained through modal testing; v max is the maximum vibration velocity of the truss vibration reduction system, obtained from the input of the vibration source excitation; d is the allowable deformation of the preload spring, comprehensively determined according to the envelope size of the vibration isolator for the truss.

[0086] The embedded vibration isolator for truss provided by the present invention flexibly selects different numbers of embedded vibration isolators for truss and arranges them at different positions of the truss structure according to the specific configuration, number, material and other characteristics of the truss, so as to control the transmission of vibration in the truss structure.

[0087] In summary, the present invention provides an embedded vibration isolator for truss, including: flexible hinge 2, outer connection sleeve 4, inner sleeve 6, preload spring 7, support plate 8, main bellows 11, auxiliary bellows 9, upper damping cylinder 10, lower damping cylinder 12, sealing screw 14, sealing gasket 13, locking block 3. Wherein, on the one hand, the flexible hinge 2 provides axial connection stiffness, and on the other hand, it releases radial rotational stiffness; the damping cavity 16 formed by the main bellows 11, auxiliary bellows 9, upper damping cylinder 10, lower damping cylinder 12, sealing screw 14, and sealing gasket 13 provides a damping effect for the embedded vibration isolator. The embedded vibration isolator for truss can be adapted to the installation of truss systems with different configurations, control the vibration of the truss, and has the characteristics of convenient installation and replacement, reliable and safe, etc.

[0088] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0089] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An embedded vibration isolator for a truss, characterized in that, Comprising: Flexible hinge (2), outer connecting sleeve (4), inner sleeve (6), locking block (3), damping cavity (16); One end of the flexible hinge (2) is provided with an external interface, and the other end is connected to the outer connecting sleeve (4); The locking block (3) is installed on the flexible hinge (2); The damping cavity (16) is respectively connected to the outer connecting sleeve (4) and the inner sleeve (6).

2. The embedded vibration isolator for a truss according to claim 1, characterized in that Multiple hollow arc grooves are provided at one end of the flexible hinge (2) connected to the locking block (3); The locking block (3) is arranged in cooperation with the outer periphery of the lower end of the flexible hinge (2).

3. The embedded vibration isolator for a truss according to claim 1, characterized in that The radial stiffness of the flexible hinge (2) is greater than the axial stiffness.

4. The embedded vibration isolator for a truss according to claim 1, wherein, The damping cavity (16) includes: upper damping cylinder (10), lower damping cylinder (12), sealing screw (14), sealing gasket (13); The lower damping cylinder (12) is fixedly connected to the outer connecting sleeve (4) by screws, The upper damping cylinder (10) is connected to the inner sleeve (6); The sealing screw (14) is arranged in the lower damping cylinder (12), and a sealing gasket (13) is interposed therebetween.

5. The embedded vibration isolator for a truss according to claim 4, characterized in that, The damping cavity (16) further includes: support plate (8), main bellows (11), auxiliary bellows (9); The support plate (8) is arranged in the inner sleeve (6); The lower damping cylinder (12) is a cylindrical body, and there is a cylindrical part in the middle section with a larger cylinder diameter than other sections, The main bellows (11) is arranged on the outer edge of the cylindrical body with a smaller cylinder diameter of the lower damping cylinder (12), and is arranged between the upper damping cylinder (10) and the lower damping cylinder (12); The auxiliary bellows (9) is arranged between the upper damping cylinder (10) and the support plate (8).

6. The embedded vibration isolator for a truss according to claim 5, characterized in that, The damping cavity (16) is filled with damping liquid. Through the relative movement among the upper damping cylinder (10), the lower damping cylinder (12) and the support plate (8), the damping liquid in the main bellows (11) and the auxiliary bellows (9) is squeezed, and the damping liquid flows through the central channel of the upper damping cylinder (10). The damping cavity (16) squeezes the internal damping liquid to flow, providing a damping effect for the truss system.

7. The embedded vibration isolator for a truss according to claim 1, characterized in that, A preloading spring (7) is provided between the inner sleeve (6) and the support plate (8).

8. An embedded vibration isolator for a truss according to claim 7, wherein, The formula for the method of selecting the stiffness coefficient of the preloading spring (7) is: where ε is the damping coefficient of the damping cavity, ω n is the modal frequency of the truss vibration damping system, v max is the maximum vibration velocity of the truss vibration damping system, and d is the allowable deformation of the spring.

9. The embedded vibration isolator for a truss according to claim 1, characterized in that, The locking block (3) fixes the elastic displacement of the flexible hinge (2) by screws.

10. A truss, characterized in that, Using the embedded vibration isolator for a truss according to any one of claims 1 to 9 for vibration isolation.

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