Quasi-zero stiffness vibration isolator based on arc-shaped spring

Abstract

The utility model relates to the technical field of vibration isolators, and particularly discloses a quasi-zero stiffness vibration isolator based on an arc-shaped spring, which comprises a bearing platform, a sealing cover, a positive stiffness linear spring, a negative stiffness component and a base, the positive stiffness linear spring is embedded in the base, the negative stiffness component is embedded in the base and is positioned at the upper end of the positive stiffness linear spring, and the sealing cover is arranged on the bearing platform. The sealing cover is fixedly connected with the base and embedded in the base, the sealing cover covers the base, one end of the bearing table sequentially penetrates through the sealing cover and the negative stiffness assembly, and the end of the bearing table makes contact with the positive stiffness linear spring. The vertical reciprocating linear motion of vibration is converted into rotary motion, under the condition that the quasi-zero stiffness stroke is not changed, the overall structure of the vibration isolator is more compact, the stability is high, the good low-frequency vibration isolation performance is achieved on the basis that the bearing capacity is guaranteed, and the vibration isolator is suitable for the vibration isolation environment with the limited installation space.

Description

Technical Field

[0001] The utility model relates to the technical field of vibration isolators, in particular to a quasi-zero stiffness vibration isolator based on arc springs. Background Art

[0002] At present, vibration refers to the reciprocating, undulating, repetitive, small or finite motion of an object passing through its equilibrium position; there are various types and forms of vibration, which are widespread in nature, engineering technology, and daily life; in most cases, vibration is harmful, which will damage human production, bring many inconveniences and even great hazards to life; in order to eliminate or reduce the adverse effects of vibration, vibration isolation design is usually required; vibration isolation means inserting an appropriate vibration isolation device between the vibration source and the vibration isolation system to isolate the direct transmission of vibration; from the perspective of energy, vibration isolation is achieved by changing the energy spectrum structure of the excitation of the vibration source on the vibration isolation system to reduce the energy passing through the frequency to suppress vibration; according to the traditional linear vibration theory, only when the external excitation frequency is greater than times the natural frequency of the vibration isolation device, the vibration isolation system will produce a vibration isolation effect; in order to obtain good vibration isolation, especially low-frequency vibration isolation performance, it is usually necessary to reduce the stiffness of the vibration isolation system, however, this will undoubtedly reduce the load-bearing capacity of the structure, therefore, the contradiction between low-frequency vibration isolation performance and high load-bearing capacity has become a major problem restricting the development of linear vibration isolation systems.

[0003] A quasi-zero stiffness vibration isolator is a non-linear vibration isolation system that uses the parallel connection of positive and negative stiffness to obtain high static stiffness and low dynamic stiffness; in the static equilibrium state, the system has a large static stiffness, providing good load-bearing capacity; when making small-amplitude vibrations near the static equilibrium position, the dynamic stiffness of the system approaches zero, achieving a lower vibration isolation starting frequency and making it have good low-frequency vibration isolation performance; the quasi-zero stiffness vibration isolator has good low-frequency vibration isolation performance on the basis of ensuring the load-bearing capacity, and has important research value and good engineering application prospects.

[0004] However, in the prior art, under large-amplitude conditions, in order to ensure sufficient quasi-zero stiffness stroke, the overall structural design size of the quasi-zero stiffness vibration isolator is usually large and cannot be applied to vibration isolation environments with limited installation space. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a quasi-zero stiffness vibration isolator based on arc springs, aiming to solve the technical problem that in the prior art, under large-amplitude conditions, in order to ensure sufficient quasi-zero stiffness stroke, the overall structural design size of the quasi-zero stiffness vibration isolator is usually large and cannot be applied to vibration isolation environments with limited installation space.

[0006] To achieve the above object, a quasi-zero stiffness vibration isolator based on an arc spring adopted by the present utility model includes a bearing platform, a sealing cover, a positive stiffness linear spring, a negative stiffness component and a base. The positive stiffness linear spring is embedded inside the base. The negative stiffness component is embedded inside the base and is located above the positive stiffness linear spring. The sealing cover is fixedly connected to the base and is embedded inside the base, and the sealing cover covers the base. One end of the bearing platform sequentially penetrates through the sealing cover and the negative stiffness component, and the end of the bearing platform contacts the positive stiffness linear spring.

[0007] Wherein, the bearing platform includes a first cylindrical platform and a second cylindrical platform. The second cylindrical platform is fixedly connected to the first cylindrical platform and is located below the first cylindrical platform. The outer wall of the second cylindrical platform has a boss, and the lower end surface of the second cylindrical platform has a frustum.

[0008] Wherein, the base has a spring clamping seat, a bearing mounting seat and threaded mounting holes. The spring clamping seat is arranged inside the base, and the positive stiffness linear spring is located above the spring clamping seat. The bearing mounting seat is arranged on the inner wall of the base. The bearing mounting seat is adapted to the second cylindrical platform and is located above the spring clamping seat. A cavity is formed between the bearing mounting seat and the base, and damping liquid is filled inside the cavity. The number of the threaded mounting holes is multiple, and the multiple threaded mounting holes are respectively arranged at one end of the base.

[0009] Wherein, the negative stiffness component includes a rotating sleeve, an arc spring and bearings. The number of the bearings is two groups. The two groups of bearings are respectively sleeved on the outer wall of the rotating sleeve, and the two groups of bearings are respectively located at both ends of the rotating sleeve. The arc spring is embedded inside the rotating sleeve. The rotating sleeve has a spring clamping groove, and the boss is adapted to the spring clamping groove.

[0010] The beneficial effects of the quasi-zero stiffness vibration isolator based on an arc spring of the present utility model are as follows: It converts the vertical reciprocating linear motion of vibration into a rotational motion. Without changing the quasi-zero stiffness stroke, the overall structure of the vibration isolator is more compact and has high stability. It has good low-frequency vibration isolation performance on the basis of ensuring the bearing capacity and is suitable for vibration isolation environments with limited installation space. Description of the Drawings

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0012] Figure 1 It is an exploded schematic view of a quasi-zero stiffness vibration isolator based on an arc spring of the present invention.

[0013] Figure 2 It is a sectional schematic view of a quasi-zero stiffness vibration isolator based on an arc spring of the present invention.

[0014] Figure 3 It is an assembly structure schematic view of the bearing platform and the rotating sleeve of the present invention.

[0015] Figure 4 It is an assembly structure schematic view of the rotating sleeve and the arc spring of the present invention.

[0016] 1 - Bearing platform, 2 - Sealing cover, 3 - Arc spring, 4 - Rotating sleeve, 5 - Bearing, 6 - Positive stiffness linear spring, 7 - Base, 8 - Damping liquid, 101 - First cylindrical platform, 102 - Second cylindrical platform, 103 - Boss, 104 - Frustum, 401 - Spring slot, 701 - Spring seat, 702 - Bearing mounting seat, 703 - Threaded mounting hole. Detailed implementation manners

[0017] Please refer to Figures 1 to 4 , the present invention provides a quasi-zero stiffness vibration isolator based on an arc spring, including a bearing platform 1, a sealing cover 2, a positive stiffness linear spring 6, a negative stiffness component, and a base 7. The positive stiffness linear spring 6 is embedded inside the base 7. The negative stiffness component is embedded inside the base 7 and is located above the positive stiffness linear spring 6. The sealing cover 2 is fixedly connected to the base 7 and is embedded inside the base 7, and the sealing cover 2 covers the base 7. One end of the bearing platform 1 sequentially penetrates through the sealing cover 2 and the negative stiffness component, and the end of the bearing platform 1 contacts the positive stiffness linear spring 6.

[0018] Further, the bearing platform 1 includes a first cylindrical platform 101 and a second cylindrical platform 102. The second cylindrical platform 102 is fixedly connected to the first cylindrical platform 101 and is located below the first cylindrical platform 101. The outer surface of the second cylindrical platform 102 has a boss 103, and the lower end surface of the second cylindrical platform 102 has a frustum 104.

[0019] Further, the base 7 has a spring clamping seat 701, a bearing mounting seat 702 and threaded mounting holes 703. The spring clamping seat 701 is arranged inside the base 7, and the positive stiffness linear spring 6 is located above the spring clamping seat 701. The bearing mounting seat 702 is arranged on the inner wall of the base 7. The bearing mounting seat 702 is adapted to the second cylindrical platform 102 and is located above the spring clamping seat 701. A cavity is formed between the bearing mounting seat 702 and the base 7, and damping liquid 8 is filled inside the cavity. The number of the threaded mounting holes 703 is multiple, and the multiple threaded mounting holes 703 are respectively arranged at one end of the base 7.

[0020] Further, the negative stiffness component includes a rotating sleeve 4, an arc spring 3 and bearings 5. The number of the bearings 5 is two groups. The two groups of bearings 5 are respectively sleeved on the outer surface wall of the rotating sleeve 4 and are respectively located at both ends of the rotating sleeve 4. The arc spring 3 is embedded inside the rotating sleeve 4. The rotating sleeve 4 has a spring clamping groove 401, and the convex platform 103 is adapted to the spring clamping groove 401.

[0021] In this embodiment, the upper end face of the first cylindrical platform 101 bears the vibration-isolated object mg, the positive stiffness linear spring 6 is compressed, the rotating sleeve 4 rotates clockwise, the upper end of the arc spring 3 is stretched and the lower end is compressed. The rotating sleeve 4 is rotated counterclockwise until the arc spring 3 returns to its free state. At this time, the gravity of the vibration-isolated object mg is completely borne by the positive stiffness linear spring 6, and the system is in a static equilibrium state. The bearing platform 1 vibrates with the vibration-isolated object mg to generate a vertical displacement. When the vertical displacement is downward, the rotating sleeve 4 rotates clockwise, the upper end of the arc spring 3 is in a stretched state and the lower end is in a compressed state. When the vertical displacement is upward, the rotating sleeve 4 rotates counterclockwise, the upper end of the arc spring 3 is in a compressed state and the lower end is in a stretched state. Near the static equilibrium position, when the rotating sleeve 4 rotates clockwise and counterclockwise with the vibration displacement, the upper and lower ends of the arc spring 3 are in an alternating state of stretching and compression, and the dynamic stiffness of the system approaches zero.

[0022] The vertical reciprocating linear motion of the vibration is converted into a rotational motion. Without changing the quasi-zero stiffness stroke, the overall structure of the vibration isolator is more compact and has high stability. It has good low-frequency vibration isolation performance on the basis of ensuring the bearing capacity and is suitable for vibration isolation environments with limited installation space.

[0023] The above-disclosed is only a preferred embodiment of the present utility model. Of course, it cannot be used to limit the scope of rights of the present utility model. Those of ordinary skill in the art can understand all or part of the processes of implementing the above embodiments, and the equivalent changes made according to the claims of the present utility model still fall within the scope covered by the utility model.

Claims

1. A quasi-zero stiffness vibration isolator based on an arc spring, characterized in that: It includes a bearing platform, a sealing cover, a positive stiffness linear spring, a negative stiffness component and a base, the positive stiffness linear spring is embedded in the base, the negative stiffness component is embedded in the base and is located at the upper end of the positive stiffness linear spring, the sealing cover is fixedly connected to the base and embedded in the base, and the sealing cover covers the base, one end of the bearing platform passes through the sealing cover and the negative stiffness component in sequence, and the end of the bearing platform is in contact with the positive stiffness linear spring.

2. A quasi-zero stiffness vibration isolator based on an arc spring as claimed in claim 1, characterized in that: The supporting platform includes a first cylindrical platform and a second cylindrical platform, the second cylindrical platform is fixedly connected to the first cylindrical platform and is located at the lower end of the first cylindrical platform, the outer wall of the second cylindrical platform has a boss, and the lower end surface of the second cylindrical platform has a frustum.

3. A quasi-zero stiffness vibration isolator based on an arc spring as claimed in claim 2, characterized in that: The base has a spring seat, a bearing mounting seat and a threaded mounting hole, the spring seat is arranged inside the base, and the positive stiffness linear spring is located at the upper end of the spring seat, the bearing mounting seat is arranged on the inner wall of the base, the bearing mounting seat and the second cylindrical table are adapted to each other, and the bearing mounting seat is located at the upper end of the spring seat, a cavity is formed between the bearing mounting seat and the base, and damping fluid is filled inside the cavity, and the number of the threaded mounting holes is multiple, and the multiple threaded mounting holes are respectively arranged at one end of the base.

4. A quasi-zero stiffness vibration isolator based on an arc spring as claimed in claim 3, characterized in that: The negative stiffness component includes a rotating sleeve, an arc spring and bearings. The number of the bearings is two groups. The two groups of bearings are respectively sleeved on the outer wall of the rotating sleeve, and the two groups of bearings are respectively located at both ends of the rotating sleeve. The arc spring is embedded in the interior of the rotating sleeve. The rotating sleeve has a spring slot, and the boss and the spring slot are adapted to each other.

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