A three-dimensional variable-damping variable-stiffness vibration isolator

Abstract

This invention belongs to the field of building structure engineering technology and discloses a three-dimensional variable damping and variable stiffness vibration isolator. The top of the outer end of the horizontal pressure member contacts the damping rubber block on the inner side of the vertical plate, and both contact surfaces are planar-variable cross-sections. The internal cavity of the horizontal pressure member is fitted onto a cylindrical boss on the vertical column. One end of a horizontal vibration isolation spring is located inside the boss on the vertical column and fitted onto the solid cylinder of the column; the other end is connected to the horizontal pressure member, creating an interaction force between the horizontal pressure member and the vertical column. During vibration, the cylinder of the vertical column slides within the cavity of the horizontal pressure member, and the horizontal vibration isolation spring provides stiffness. Vertical vibration isolation springs are fitted onto the cylindrical bosses of the top and bottom plates, respectively, providing anti-sway capability. This invention introduces a nonlinear damping mechanism, achieving adaptive changes in damping characteristics by adjusting friction and geometry. The independent stiffness design of the vertical and horizontal directions ensures that the system maintains high vibration isolation performance in all three directions, exhibiting strong adaptability in multi-dimensional environments.

Description

Technical Field

[0001] This invention belongs to the field of building structure engineering technology, specifically relating to a three-dimensional variable damping and variable stiffness vibration isolator. Background Technology

[0002] In complex vibration environments such as building structures, transportation vehicles, and industrial plants, vibrations caused by traffic loads, equipment operation, or natural disasters can be transmitted to the equipment through the structure, resulting in irreversible damage in many aspects, such as component displacement and collision, deformation of elastic elements, intensified resonance, component wear and fatigue, loosening and falling off of connectors, fracture of brittle materials, decrease in measurement accuracy, and failure of moisture-proof seals. This seriously affects the normal operation of the equipment and significantly shortens its service life, causing huge economic losses.

[0003] Vibration isolation is an effective strategy to reduce the transmission of environmental vibrations to equipment through structures. Modern vibration isolation technologies are mainly divided into three categories: active control, semi-active adjustment, and passive isolation. Among them, active and semi-active vibration isolation can adapt to various working conditions and have high control precision, but their engineering applications are limited due to complex structures, the need for continuous external power supply, high costs, and actuator stability issues. In contrast, passive vibration isolation has become the preferred solution in engineering practice due to its advantages of not requiring external energy, simple structure, low cost, and high reliability. However, traditional passive vibration isolation devices are mostly designed for unidirectional vibrations, while actual engineering vibrations are mostly multidimensional. Therefore, developing multidimensional vibration isolators that can adapt to complex multidimensional environments and provide more comprehensive protection for equipment is an important research direction for improving the performance of vibration isolators. Summary of the Invention

[0004] To address the problem of equipment vibration control under complex multidimensional vibration conditions, a novel three-dimensional variable damping and variable stiffness vibration isolator is proposed based on the design concept of "modular combination of vertical and horizontal vibration isolation units".

[0005] The technical solution of the present invention is as follows: A three-dimensional variable damping and variable stiffness vibration isolator includes a shell, an upper cap, a bottom plate, a top plate, a vertical vibration isolation spring, a vertical plate, a connector, a column, a horizontal pressure component, a damping rubber block, a horizontal vibration isolation spring, a solid cylindrical column, an upper cylindrical boss, a lower cylindrical boss, and a rubber clamp. The top plate is circular, and its lower surface is fixed with no less than four upper cylindrical bosses, which are symmetrically arranged at equal distances from the center of the top plate. The upper surface of the bottom plate is fixed with lower cylindrical bosses in the same position and number as the upper cylindrical bosses. A vertical vibration isolation spring is fitted between each set of upper and lower cylindrical bosses to form a positioning constraint on the vertical vibration isolation spring, thus forming a vertical vibration isolation system. The column is located at the center of the lower surface of the top plate, and the two are an integral structure. Each of the four sides of the column has a solid cylinder and a slot, with the solid cylinder located within the slot. One end of the horizontal pressure member has a cylindrical cavity, positioned opposite the solid cylinder of the column. The other end of the horizontal pressure member is a solid umbrella-shaped structure, and its outer surface is designed with a variable cross-section that transitions from the central plane to the outer perimeter. One end of the horizontal vibration isolation spring is fixed in the slot on the column and fits around the solid cylinder of the column. The other end of the horizontal vibration isolation spring is in contact with the inner surface of the solid umbrella-shaped structure of the horizontal pressure member. When vibration occurs, the solid cylinder of the column slides within the cylindrical cavity of the horizontal pressure member. The vertical plate is located inside the vertical vibration isolation system and is fixed to the base plate by connecting parts. The damping rubber block is fixed inside the vertical plate, which is directly opposite the horizontal pressure member. The compression of the horizontal vibration isolation spring makes the outer surface of the solid umbrella-shaped structure of the horizontal pressure member fit seamlessly with the inner concave surface of the damping rubber block. The horizontal vibration isolation spring provides preload, forming a three-dimensional variable damping and variable stiffness vibration isolator. The outer shell is fixed to the base plate, and the upper cap is fixed to the top plate. There are gaps between the outer shell and the upper cap and the top plate to ensure that no collision occurs under extreme displacement, which is used to protect the three-dimensional variable damping and variable stiffness vibration isolator.

[0006] The top center of the cap has a screw hole for supporting the base or foundation of the vibration-isolated equipment; the bottom of the cap has a screw rod, and the cap is connected to the top plate through the bottom screw rod. A rubber clip is provided between the two to prevent the connection from loosening.

[0007] Both the horizontal and vertical vibration isolation springs are helical compression steel springs, manufactured using high fatigue-grade oil-quenched and tempered spring steel wire VDCrSi. The stiffness of the horizontal vibration isolation spring is calculated using the following formula: In the formula: k is the stiffness of the helical compression spring, in N / mm; P is the upper load, in N.

[0008] The beneficial effects of this invention are as follows: This invention can be widely applied to equipment vibration control under complex multidimensional vibration conditions. It features at least four vertical vibration isolation springs, providing strong vertical vibration isolation and anti-sway capabilities. While maintaining the coordinated operation of the vertical and horizontal vibration isolation units, an independently adjustable horizontal vibration isolation spring is introduced to provide a certain stiffness in the horizontal direction, thereby enhancing the three-dimensional vibration isolation performance and improving the independent controllability of the horizontal stiffness, facilitating precise control of the vibration isolation parameters in each direction. When the horizontal pressure component moves relative to the damping rubber block, frictional damping is generated. Since both contact surfaces are designed as planar variable cross-sections, during vibration, the horizontal pressure component enters the variable cross-section section of the damping rubber block, providing the system with nonlinear compressive restoring force and frictional damping force, resulting in excellent three-dimensional vibration isolation capabilities. Attached Figure Description

[0009] Figure 1 This is a cross-sectional front view of the present invention.

[0010] Figure 2 This is a schematic diagram of the appearance of the present invention.

[0011] Figure 3 This is a schematic diagram of the internal structure of the present invention.

[0012] Figure 4 This is a detailed cross-sectional view of the contact between the column, horizontal pressure member and damping rubber block of the present invention.

[0013] Figure 5 This is an isometric schematic diagram of the damping rubber block in the device of the present invention.

[0014] Figure 6 This is a cross-sectional schematic diagram of the damping rubber block in the device of the present invention.

[0015] Figure 7 This is an isometric schematic diagram of the horizontal pressure component in the device of the present invention.

[0016] Figure 8 This is a cross-sectional schematic diagram of the horizontal pressure component in the device of the present invention.

[0017] In the diagram: 1. Outer shell; 2. Upper cap; 3. Base plate; 4. Top plate; 5. Vertical vibration isolation spring; 6. Vertical plate; 7. Connecting piece; 8. Column; 9. Horizontal pressure piece; 10. Damping rubber block; 11. Horizontal vibration isolation spring; 12. Solid cylinder of the column; 13. Upper cylindrical boss; 14. Lower cylindrical boss; 15. Rubber clamp. Detailed Implementation

[0018] The present invention will now be further described with reference to the accompanying drawings in the embodiments of the present invention.

[0019] Figure 1 , Figure 2 and Figure 3 The illustration shows a cross-sectional view, an external schematic diagram, and an internal structural schematic diagram of a three-dimensional variable damping and variable stiffness vibration isolator according to an embodiment of the present invention.

[0020] During vibration, the vibration isolator typically reciprocates around its static equilibrium position. When resonance occurs, the amplitude increases, and the isolator moves further away from its equilibrium position. As the excitation frequency increases, it enters the isolation phase, at which point the vibration amplitude significantly decreases, and the isolator mainly vibrates slightly near its static equilibrium position. Therefore, using a low-damping design in the vicinity of the equilibrium position can approximate a small damping ratio in the isolation zone, thereby reducing the vibration transmissibility in the high-frequency range. Conversely, setting high-damping characteristics in the large displacement region can approximate a large damping ratio in the resonance zone, suppressing resonance peaks and effectively reducing the impact of shocks on the equipment.

[0021] Under standard load, when the vibration isolator reaches static equilibrium, the solid umbrella-shaped convex surface of the horizontal pressure member 9 aligns with the center of the concave surface of the damping rubber block 10, and their planar areas form contact compression. At this time, the relative sliding between the end of the horizontal pressure member 9 and the planar section of the damping rubber block 10 will generate Coulomb friction damping. When the displacement of the horizontal pressure member 9 increases and it enters the variable cross-section region of the damping rubber block 10, the system restoring force transforms into a combination of friction and compression. The damping rubber block 10 adopts a planar-variable cross-section design. When the vibration isolation system vibrates near the equilibrium position, the horizontal pressure member 9 slides in the planar section of the damping rubber block 10, generating relatively small damping. When the displacement increases, the horizontal pressure member 9 enters the variable cross-section region. At this time, the compression of the horizontal vibration isolation spring 11 gradually increases, and the friction and compression between the horizontal pressure member 9 and the damping rubber block 10 gradually intensifies, resulting in a larger damping force.

[0022] During vertical vibration, the three-dimensional variable damping and variable stiffness isolator causes the upper cap 2 to move up and down, which in turn causes the top plate 4 to move. The vertical isolation spring 5 is compressed, and the top plate 4 also causes the column 8 to move vertically, thus moving the horizontal pressure member 9. As the horizontal pressure member 9 moves up and down, it gradually moves away from its static equilibrium position, increasing the force exerted by the damping rubber block 10 on the horizontal pressure member 9, and compressing the horizontal isolation spring 11. During vertical vibration, the three-dimensional variable damping and variable stiffness isolator, with its four sets of upper cylindrical bosses 13, lower cylindrical bosses 14, and vertical isolation springs, generates friction and compression, providing nonlinear elastic restoring force and nonlinear frictional damping force for the vertical isolation system.

[0023] When the vibration isolation system experiences horizontal vibration, the upper cap 2 moves left and right under the action of the horizontal force. The upper cap 2 drives the top plate 4 to move left and right. Similarly, the top plate 4 also drives the column 8 to move. At this time, the force generated by the damping rubber block 10, the horizontal pressure member 9, the horizontal vibration isolation spring 11 and the column 8, which are perpendicular to the vibration direction, provides linear elastic restoring force for the vibration isolation system. The magnitude of the force mainly depends on the deformation of the horizontal vibration isolation spring 11. The force generated between the damping rubber block 10, the horizontal pressure member 9, the horizontal vibration isolation spring 11 and the column 8, which are parallel to the vibration direction, can provide nonlinear compression restoring force and friction damping force for the vibration isolation system.

[0024] In summary, this three-dimensional variable damping and variable stiffness vibration isolator provides linear elastic restoring force through four vertical isolation springs 5, and a total of four sets of variable damping and variable stiffness structures provide nonlinear compressive restoring force and nonlinear frictional damping force during vertical vibration. During horizontal vibration, since the horizontal isolation springs 11, parallel to the vibration direction, provide linear elastic restoring force, only two sets of variable damping and variable stiffness structures generate friction and compression to provide nonlinear compressive restoring force and nonlinear frictional damping force for the vibration isolation system. Furthermore, the damping parameters of the vibration isolation device can be changed by altering the contact surface dimensions between the damping rubber block 10 and the horizontal pressure member 9. The horizontal stiffness can be designed by changing the hardness of the damping rubber block 10 and the horizontal isolation springs 11, thus providing designable three-dimensional stiffness and damping. This invention has a simple structure, controllable cost, and good application prospects.

Claims

1. A three-dimensional variable-damper variable-stiffness vibration isolator, characterized by, The three-dimensional variable damping and variable stiffness vibration isolator includes a shell (1), an upper cap (2), a bottom plate (3), a top plate (4), a vertical vibration isolation spring (5), a vertical plate (6), a connector (7), a column (8), a horizontal pressure piece (9), a damping rubber block (10), a horizontal vibration isolation spring (11), a solid cylindrical column (12), an upper cylindrical boss (13), a lower cylindrical boss (14), and a rubber clip (15). The top plate (4) is circular, and at least four upper cylindrical bosses (13) are fixedly provided on its lower surface, and are symmetrically arranged at equal distances from the center of the top plate (4); the upper surface of the bottom plate (3) is fixed with lower cylindrical bosses (14) in the same position and number as the upper cylindrical bosses (13); a vertical vibration isolation spring (5) is fitted between each set of upper cylindrical bosses (13) and lower cylindrical bosses (14), forming a positioning constraint on the vertical vibration isolation springs (5) to form a vertical vibration isolation system; The column (8) is located at the center of the lower surface of the top plate (4), and the two are an integral structure; the four sides of the column (8) are provided with a solid cylindrical body (12) and a slot, and the solid cylindrical body (12) is located in the slot; one end of the horizontal pressure member (9) is provided with a cylindrical cavity, which is opposite to the solid cylindrical body (12) of the column; the other end of the horizontal pressure member (9) is a solid umbrella-shaped structure, and the outer surface is designed as a variable cross section transitioning from the central plane to the outer periphery; one end of the horizontal vibration isolation spring (11) is fixed in the slot on the column (8) and sleeved on the solid cylindrical body (12) of the column; the other end of the horizontal vibration isolation spring (11) is in contact with the inner surface of the solid umbrella-shaped structure of the horizontal pressure member (9); when vibration occurs, the solid cylindrical body (12) of the column slides in the cylindrical cavity of the horizontal pressure member (9); The vertical plate (6) is located inside the vertical vibration isolation system. It is fixed to the base plate (3) by the connector (7). The damping rubber block (10) is fixed inside the vertical plate (6) which is directly opposite to the horizontal pressure member (9). The compression of the horizontal vibration isolation spring (11) makes the outer surface of the solid umbrella-shaped structure of the horizontal pressure member (9) fit seamlessly with the inner concave surface of the damping rubber block (10). The horizontal vibration isolation spring (11) provides preload to form a three-dimensional variable damping and variable stiffness vibration isolator. The outer shell (1) is fixed on the base plate (3), the upper cap (2) is fixed on the top plate (4), and there are gaps between the outer shell (1), the upper cap (2) and the top plate (4) to ensure that no collision occurs under the ultimate displacement, which is used to protect the three-dimensional variable damping and variable stiffness vibration isolator.

2. The three-dimensional variable-damper variable-stiffness vibration isolator of claim 1, wherein, The top center of the cap (2) has a screw hole for supporting the base or foundation of the vibration isolation equipment; the bottom of the cap (2) is provided with a screw rod, and the cap (2) is connected to the top plate (4) through the bottom screw rod. A rubber clip (15) is provided between the two to prevent the connection between the two from becoming loose.

3. The three-dimensional variable damping and variable stiffness vibration isolator according to claim 1, characterized in that, Both the horizontal vibration isolation spring (11) and the vertical vibration isolation spring (5) are helical compression steel springs, made of high fatigue-grade oil-quenched and tempered spring steel wire. The stiffness of the horizontal vibration isolation spring (11) is calculated using the following formula: In the formula: k is the stiffness of the helical compression spring, in N / mm; P is the upper load, in N.

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