A multi-directional broadband quasi-zero stiffness vibration isolation device

Abstract

This invention belongs to the field of vibration isolation technology, specifically providing a multi-directional broadband quasi-zero stiffness vibration isolation device, including a long shaft, a lower base, an integrated quasi-zero stiffness vibration isolator, an upper shell, a bushing, a permanent magnet, a magnetic yoke, a conductor shell, a middle shell, and bearing components. These components integrate an integrated quasi-zero stiffness vibration isolator and an eddy current damper dual system, achieving a synergistic vibration isolation function of stiffness buffering and damping energy dissipation. Relying on the excellent low-frequency vibration isolation characteristics of the quasi-zero stiffness structure, combined with the contactless and wear-free energy dissipation method of eddy current damping, it effectively improves the problems of easy wear and high maintenance costs of traditional damping structures; simultaneously, with the guiding constraint design of the linear bearing, it ensures precise, stable, and reliable vibration isolation motion, and can be widely applied in vehicle vibration reduction and isolation scenarios.

Description

Technical Field

[0001] This invention belongs to the field of vibration isolation technology, and specifically provides a multi-directional broadband quasi-zero stiffness vibration isolation device. Background Technology

[0002] Vibration isolation is a key means to ensure the normal operation of precision equipment and improve the fatigue life of structures. Traditional linear vibration isolators, such as metal springs, rubber isolators, and air springs, are only effective when the disturbance frequency is greater than the natural frequency of the isolation system. Effective vibration attenuation can only be provided when the stiffness is doubled. Quasi-zero stiffness isolators typically use positive stiffness elements and negative stiffness elements in parallel to achieve nonlinear mechanical characteristics of "high static stiffness and low dynamic stiffness", which can significantly isolate low-frequency vibrations.

[0003] In practical engineering, vibration sources often generate complex vibrations in multiple directions and with multiple degrees of freedom. For example, machine tools are subjected to excitations from both vertical and horizontal directions. If only a quasi-zero stiffness design is applied in one direction while conventional vibration isolation is used in other directions, the overall low-frequency vibration isolation effect of the system will be significantly reduced. Constructing a multi-directional vibration isolation platform by combining multiple unidirectional quasi-zero stiffness units can improve the overall low-frequency vibration isolation effect of the system. Therefore, designing a multi-directional broadband quasi-zero stiffness isolator is essential. Summary of the Invention

[0004] To address the existing technical problems, this invention provides a multi-directional broadband quasi-zero stiffness vibration isolation device, integrating a quasi-zero stiffness vibration isolator and an eddy current damper into a dual system, achieving coordinated vibration isolation functions of stiffness buffering and damping energy dissipation. Utilizing the excellent low-frequency vibration isolation characteristics of the quasi-zero stiffness structure, combined with the contactless and wear-free energy dissipation method of eddy current damping, it effectively improves the problems of easy wear and high maintenance costs associated with traditional damping structures. Simultaneously, the linear bearing's guiding constraint design ensures precise, stable, and reliable vibration isolation motion, making it widely applicable to scenarios such as vehicle vibration reduction and isolation. Specifically, it includes an outer shell, a guiding unit, and a vibration isolation unit.

[0005] The outer shell includes a lower base, a middle shell, and an upper outer shell; these are assembled together to form an integral structure with internal chambers.

[0006] The guide structure includes a long shaft and a set of fixed bearings. The body of the long shaft is installed inside the outer housing and can move up and down inside the outer housing. The lower end is located inside the lower base and is at a distance from the bottom surface inside the lower base. The upper end of the base and the lower end of the upper housing are respectively provided with bearing mounting positions, and bearings are installed thereon, so that the long shaft passes through the inner rings of the two bearings to achieve movement direction constraint.

[0007] The vibration isolation unit includes a quasi-zero stiffness isolator, a permanent magnet, a yoke, a bushing, and a conductor shell. The quasi-zero stiffness isolator comprises multiple elastic curved beams in a divergent design, with the head end of each beam fixed to a central ring and the tail end fixed to a stepped surface inside the upper shell. The central ring is fitted around the outer circumference of a long shaft, which moves up and down within the central ring, thereby driving the quasi-zero stiffness isolator to generate quasi-zero stiffness. During the downward compression of the long shaft, eddy current dampers provide damping and buffering to reduce impact force. When the upper end of the long shaft contacts the quasi-zero stiffness isolator, it further compresses the isolator for low-frequency vibration isolation.

[0008] The bushing surface is fitted with permanent magnets and yokes at a preset interval. After assembly, they are fitted onto the outer circumference of the long axis and the whole is located inside the middle shell. The conductor shell is fixed at a preset limit position inside the middle shell, and a gap is reserved between its inner wall and the movement trajectory of the permanent magnets and yokes.

[0009] Furthermore, the diameter of the upper end of the long shaft is larger than the diameter of the central ring, which limits the movement of the long shaft in the lower direction (towards the lower base).

[0010] Furthermore, an end cap with a central hole is installed at the upper end of the upper housing, through which the long shaft passes.

[0011] This invention provides an eddy current damping vibration isolation device that integrates a quasi-zero stiffness vibration isolator and an eddy current damper into a single system, achieving synergistic vibration isolation functions of stiffness buffering and damping energy dissipation. Leveraging the excellent low-frequency vibration isolation characteristics of the quasi-zero stiffness structure, combined with the contactless and wear-free energy dissipation method of eddy current damping, it effectively improves the problems of easy wear and high maintenance costs associated with traditional damping structures. Simultaneously, the linear bearing's guiding constraint design ensures precise, stable, and reliable vibration isolation motion, making it widely applicable to vibration reduction and isolation scenarios in vehicles. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the external structure of the present invention;

[0015] Figure 2 This is a schematic diagram of some of the internal components of the present invention;

[0016] Figure 3This is a cross-sectional structural diagram of the present invention;

[0017] Figure 4 This is a schematic diagram of the location and structure of an integrated quasi-zero stiffness vibration isolator.

[0018] In the diagram, 1. Long shaft; 2. Lower base; 3. Integrated quasi-zero stiffness vibration isolator; 4. Upper outer shell; 5. Bushing; 6. Permanent magnet; 7. Magnetic yoke; 8. Conductor shell; 9. Middle outer shell; 10. Bearing; 11. Curved beam. Detailed Implementation

[0019] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of systems consistent with some aspects of the invention as detailed in the appended claims.

[0020] This invention provides a multi-directional broadband quasi-zero stiffness vibration isolation device. The core components of this device include:

[0021] refer to Figure 1-4 The device consists of a long shaft (1), a lower base (2), an integrated quasi-zero stiffness vibration isolator (3), an upper outer shell (4), a bushing (5), a permanent magnet (6), a magnetic yoke (7), a conductor shell (8), a middle outer shell (9), and a bearing (10). The components work together to form a vibration isolator comprising two isolation units: an integrated quasi-zero stiffness isolator and an eddy current damper, as detailed below:

[0022] The integrated quasi-zero stiffness vibration isolator 3 includes multiple elastic curved beams in a divergent design. The head end of the curved beam is fixed on the central ring, and the tail end is fixed on the internal mounting surface inside the upper shell. The mounting surface is a stepped surface design. The height of the vibration isolator is changed by the up and down movement of the long axis, and the movement trajectory is constrained by the linear bearing to ensure that the device always moves along the axis.

[0023] In the attached diagram, component 1 is a guide shaft that passes through two linear bearing components 10, allowing the guide shaft to move along the axis of the device. This movement drives the integrated quasi-zero stiffness isolator 3, providing low-frequency vibration isolation. The lower base 2, combined with the middle and upper housings, forms the outer shell of the device, providing protection for the internal components. The integrated quasi-zero stiffness isolator 3, when the guide shaft moves, drives component 3 to provide low-frequency vibration isolation. The integrated quasi-zero stiffness isolator 3 is fixed to the internal mounting surface of the upper housing 4, ensuring that the axis of the through hole in the middle of the isolator coincides with the central axis of the upper housing 4. The guide shaft is inserted from the upper end of the upper housing 4, then passes through the through hole of the middle ring of the isolator 3 and the linear bearing component 10. The device vibrates up and down through the long shaft, causing the isolator to move up and down along the axis of the device, thus providing low-frequency vibration isolation performance.

[0024] The eddy current damper is a damping system consisting of a permanent magnet coupled with a conductor shell.

[0025] The eddy current damper consists of a guide shaft 1, a lower base 2, a bushing 5, several permanent magnets 6, several magnetic yokes 7, a conductor shell 8, a middle outer shell 9, two bearings 10, and fixed connecting parts.

[0026] A guide shaft passes through two linear bearings 10, allowing it to move along the axis of the device. It is fixed in place by bushings 5, which in turn move several permanent magnets 6 and a yoke 7. Utilizing the principle of electromagnetic induction, the relative movement of the permanent magnets and the conductor shell 8 generates eddy currents on the conductor shell. The magnetic field generated by these eddy currents reacts with the original magnetic field, creating an eddy current damping force. Bushings 5, fixed to the guide shaft, secure the permanent magnets and yoke to the guide shaft. The two linear bearings 10 ensure the guide shaft moves axially. The permanent magnets 6, fixed to the guide shaft by bushings, cooperate with the conductor shell to provide eddy current damping force. Component 8 is the conductor shell: fixed by a central shell, it cooperates with the permanent magnets to generate eddy current damping force. Component 9 is the central shell, cooperating with the conductor shell's shaft hole. Its material properties prevent external magnetic field lines from being exposed. It combines with the upper shell component 4 and the lower shell component 2 to provide external protection for the entire device. Component 10 is a linear bearing, installed inside the middle housing, which allows the guide shaft to move along the axis of the device.

[0027] The specific installation process is as follows:

[0028] First, fix the ring around the integrated quasi-zero stiffness vibration isolator 3 to the pre-set mounting surface of the upper housing 4, ensuring that the axis of the through hole in the middle of the integrated quasi-zero stiffness vibration isolator 3 coincides with the central axis of the upper housing 4. Then, insert the long shaft 1 from the upper end of the upper housing 4, and then through the through hole in the middle of the integrated quasi-zero stiffness vibration isolator 3 to complete the initial assembly.

[0029] Next, the first bearing 10 is installed at the bearing mounting position on the upper end of the middle outer shell 9. The conductor shell 8 is fixed on the preset step inside the middle outer shell 9. The middle outer shell 9, equipped with the first bearing 10 and the conductor shell 8, is then inserted into the lower end of the long shaft 1, allowing the long shaft 1 to pass through the inner ring of the bearing 10, thus achieving preliminary directional constraint. The upper end of the middle outer shell 9 is then connected to the lower end of the upper outer shell 4 via a fixed connector. Several permanent magnets 6 and yokes 7 are pre-assembled on the surface of the bushing 5 at preset intervals, so that the yoke 7 evenly separates adjacent permanent magnets 6, forming a complete magnetic field unit. The assembled bushing 5 is then inserted into the lower end of the long shaft 1 and fixed at the preset limit position in the middle of the long shaft, ensuring that the bushing moves synchronously with the long shaft. A reasonable gap is reserved between the inner wall of the conductor shell 8 and the permanent magnets 6 and yoke 7, ensuring that the permanent magnets 6 and yoke 7 are completely within the area surrounded by the conductor shell 8.

[0030] Install the second bearing 10 to the bearing mounting position at the lower end of the middle housing 9, so that the long shaft 1 passes through the inner ring of the bearing 10, thus completing the constraint on the direction of movement of the long shaft. Strict calibration is required during installation to ensure that the axes of the inner rings of the two bearings 10 coincide and are aligned with the axis of the central through hole of the integrated quasi-zero stiffness vibration isolator 3, avoiding motion interference. Finally, install the lower base 2 at the lower end of the middle housing 9, sealing the bottom of the middle housing, while aligning the lower end of the long shaft 1 with the central area of ​​the lower base 2, completing the assembly of the entire device.

[0031] The operation method is as follows:

[0032] The assembled vibration isolation device is connected to the vibration reduction link of equipment such as unmanned vehicles. The upper part of the long shaft 1 is fixed to the precision components of the equipment, and the lower base 2 is fixed to the vehicle frame. When the equipment is subjected to vibration, the long shaft 1 will move towards the lower base 2. Since the diameter of the upper end of the long shaft 1 is larger than the diameter of the through hole in the middle of the integrated quasi-zero stiffness vibration isolator 3, the long shaft 1 will push the integrated quasi-zero stiffness vibration isolator 3 to deform. The curved beam 11 will generate resistance in the opposite direction of movement, realizing the initial buffering of vibration. At the same time, the long shaft 1 drives the bushing 5 and the permanent magnets 6 and yoke 7 on the surface to move synchronously. The yoke 7 can concentrate the magnetic field of the permanent magnet 6 and reduce magnetic leakage. However, when the permanent magnet 6 moves, the conductor shell 8 is fixed in the middle outer shell 9 and its position remains unchanged, thus forming a relative movement between the permanent magnet 6 and the conductor shell 8. An induced current will be generated in the conductor shell 8, thus forming electromagnetic damping that hinders the movement of the permanent magnet 6, and also hinders the movement of the long shaft 1, realizing further buffering of vibration. This process converts the kinetic energy of the long shaft 1 into heat energy generated by the current and dissipates it, realizing the consumption of vibration energy. After the vibration ends, the long shaft 1 is reset under the elastic restoring force of the integrated quasi-zero stiffness vibration isolator 3. By repeating the above "buffering-energy dissipation-reset" process, the vibration isolation effect can be continuously achieved. Throughout the process, the two bearings 10 will constrain the long shaft 1 to move only along the axial direction, ensuring the accuracy and stability of the vibration isolation operation.

[0033] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these changes and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A multidirectional broadband quasi-zero stiffness vibration isolation device, characterized in that, Includes outer casing, guide unit, and vibration isolation unit. The outer shell includes a lower base, a middle shell, and an upper outer shell; these are assembled together to form an integral structure with internal chambers. The guide structure includes a long shaft and a set of fixed bearings. The body of the long shaft is installed inside the outer housing and can move up and down inside the outer housing. The lower end is located inside the lower base and is at a distance from the bottom surface inside the lower base. The upper end of the base and the lower end of the upper housing are respectively provided with bearing mounting positions, and bearings are installed thereon, so that the long shaft passes through the inner rings of the two bearings to achieve movement direction constraint. The vibration isolation unit includes a quasi-zero stiffness isolator, a permanent magnet, a yoke, a bushing, and a conductor shell. The quasi-zero stiffness isolator comprises multiple elastic curved beams in a divergent design, with the head end of the curved beam fixed to a central ring and the tail end fixed to a stepped surface inside the upper shell. The central ring is fitted around the outer circumference of a long shaft, which moves up and down within the central ring, driving the quasi-zero stiffness isolator to move and generate quasi-zero stiffness. The bushing surface is fitted with the permanent magnet and the yoke at a preset interval, and after assembly, it is fitted around the outer circumference of the long shaft, with the entire assembly located inside the middle shell. The conductor shell is fixed at a preset limit position inside the middle shell, with a pre-reserved gap between its inner wall and the movement trajectory of the permanent magnet and the yoke.

2. The multi-directional broadband quasi-zero stiffness vibration isolation device as described in claim 1, characterized in that, The diameter at the upper end of the major axis is larger than the diameter of the central ring.

3. A multidirectional broadband quasi-zero stiffness vibration isolation device according to claim 1, wherein An end cap with a central hole is installed at the upper end of the outer casing.

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