Debugging method of compact horizontal quasi-zero stiffness vibration isolator with single-pair oscillating bar structure

Abstract

The invention relates to a debugging method of a compact horizontal quasi-zero stiffness vibration isolator constructed by a single pair of swing rods, the vibration isolator comprises a quasi-zero stiffness mechanism and a constant force mechanism which have the same structure, and the quasi-zero stiffness mechanism comprises a first connecting rod unit, a second connecting rod unit, a guide rod, a vertical extension spring and a horizontal extension spring; the first connecting rod unit and the second connecting rod unit are symmetrically distributed on the two sides of the horizontal extension spring, the first connecting rod unit comprises a swing rod and a connecting rod, one end of the swing rod is hinged to the rack, and the other end of the connecting rod is hinged to the guide rod; one end of a horizontal extension spring is fixed with the rack, and the other end is fixed with the guide rod; two ends of a vertical extension spring are respectively connected with hinge points of swing rods and connecting rods in the first and second connecting rod units; the constant force mechanism is used for applying horizontal application force to the guide rod, so that the quasi-zero stiffness mechanism is in a static balance state. Compared with the prior art, the invention has the advantages of horizontal vibration reduction, few parts, small occupied space and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of low-frequency vibration isolation, in particular to a debugging method of a compact horizontal quasi-zero stiffness vibration isolator with a single pair of swing rod structure. BACKGROUND

[0002] Vibration is the most common phenomenon in nature, and can be seen everywhere in daily life and production, such as swaying leaves, heartbeats, and car bumps. From simple pendulums to complex bodies, from microcosmic objects to macroscopic bodies, vibration phenomena are ubiquitous. Many of them will seriously affect people's life and industrial production, causing a lot of losses. Therefore, vibration isolation is a permanent research topic for human beings.

[0003] The prerequisite for isolating low-frequency vibration is that the natural frequency of the vibration isolation system must be very low. Since ordinary linear vibration isolation systems cannot overcome the trade-off between stiffness and load capacity, they cannot achieve this. Nonlinear vibration isolation systems composed of positive and negative stiffness in parallel can solve this problem. It uses the principle of positive and negative stiffness cancellation to make the stiffness of the system close to zero, also known as quasi-zero stiffness vibration isolation system. While ensuring the load capacity of the system, the stiffness of the system is effectively reduced, so that the natural frequency of the entire system is greatly reduced, the starting vibration isolation frequency is reduced, the vibration isolation interval is increased, and the vibration isolation capacity is improved, achieving low-frequency vibration isolation.

[0004] For example, the invention disclosed in CN106402267A discloses a tensile quasi-zero stiffness vibration isolator and its implementation method. The vibration isolator is composed of a negative stiffness mechanism in parallel with a positive stiffness main spring, wherein the negative stiffness mechanism is composed of a tensile spring, a connecting rod, a slider and a guide rail, which can produce negative stiffness in the vertical direction and avoid the instability of the compression spring. When fine-tuning in the horizontal direction, it can ensure the left-right symmetry of the structure. According to the principle of positive and negative stiffness cancellation, after connecting the negative stiffness mechanism in parallel with the positive stiffness spring, the stiffness of the vibration isolator at the equilibrium position is close to zero, and the natural frequency is also close to zero, so that the starting vibration isolation frequency is greatly reduced, the vibration isolation interval is increased, and the ability to isolate low-frequency or ultra-low-frequency vibration is achieved.

[0005] However, the movement of the slider, slide rail and other mechanisms in the above-mentioned tensile quasi-zero stiffness vibration isolator makes the tensile spring produce negative stiffness. This structure is relatively complex, occupies a large space, and is not suitable for some space-limited spaces.

[0006] In summary, the existing quasi-zero stiffness vibration isolator is complex, requires a large number of parts, and cannot be used in some space-limited application scenarios. Therefore, it is necessary to design a small, compact and few-part quasi-zero stiffness vibration isolator to effectively expand the application scenarios of quasi-zero stiffness vibration isolators. SUMMARY

[0007] The purpose of the present application is to overcome the defects of the prior art, such as complex zero stiffness isolator, large number of required parts, large occupied space and limited use scenarios, and to provide a debugging method for a single pair of swing rod structure compact horizontal direction quasi-zero stiffness isolator.

[0008] The purpose of the present application can be achieved by the following technical solutions:

[0009] A debugging method for a single pair of swing rod structure compact horizontal direction quasi-zero stiffness isolator, characterized in that the isolator comprises a quasi-zero stiffness mechanism and a constant force mechanism with the same structure, the quasi-zero stiffness mechanism comprising a first connecting rod unit, a second connecting rod unit, a guide rod, a vertical tension spring and a horizontal tension spring;

[0010] The first connecting rod unit and the second connecting rod unit have the same structure and are symmetrically distributed on both sides of the horizontal tension spring, the first connecting rod unit comprising a swing rod and a connecting rod, one end of the swing rod being hinged to a rack, the other end being hinged to the connecting rod, the other end of the connecting rod being hinged to the guide rod, one end of the horizontal tension spring being fixed to the rack, the other end being fixed to the guide rod;

[0011] Both ends of the vertical tension spring are connected to the hinged points of the swing rod and the connecting rod in the first connecting rod unit and the second connecting rod unit, respectively; the constant force mechanism is used to apply a horizontal constant force to the guide rod, so that the quasi-zero stiffness mechanism is in a static equilibrium state;

[0012] The debugging method for the quasi-zero stiffness mechanism comprises the following steps:

[0013] S11: Constructing the quasi-zero stiffness mechanism so that the quasi-zero stiffness mechanism is in an initial state; the initial state refers to the state that the horizontal tension spring is at a free length when the two swing rods are hinged to the guide rod; in the initial state, the swing rod is in a horizontal state;

[0014] S12: Determining the basic dimensionless parameters, including the dimensionless pre-tension of the vertical tension spring the dimensionless projection length of the connecting rod in the vertical direction in the initial state the dimensionless length of the swing rod and the stiffness ratio α of the vertical tension spring and the horizontal tension spring and the displacement x of the hinged end of the guide rod from the initial state, in any x position, the swing rod has a rotation angle θ x ;

[0015] S13: Dimensionalizing the applied force f of the quasi-zero stiffness mechanism to obtain the dimensionless applied force

[0016]

[0017] the dimensionless applied force For the first derivative, since the use of approximate dimensionless stiffness expression is obtained:

[0018]

[0019] wherein:

[0020] The dimensionless parameter form in the above formula is as follows:

[0021]

[0022] S14: At the static equilibrium position, let the stiffness be equal to zero, and the quasi-zero stiffness parameter condition is obtained If the designed parameter value satisfies the parameter relationship, the nonlinear quasi-zero stiffness characteristic can be obtained;

[0023] At the static equilibrium position, let the stiffness be equal to zero and the second derivative of the stiffness be equal to zero, and the quasi-zero stiffness parameter condition is obtained and If the designed parameter value satisfies 0<α<0.25 and the constant value quasi-zero stiffness characteristic can be obtained;

[0024] S15: Draw the curve of the quasi-zero stiffness mechanism, the application force applied to the quasi-zero stiffness mechanism in the motion direction, when the quasi-zero stiffness mechanism is in the static equilibrium position, divide by the gravitational acceleration to obtain the vibration isolation mass, and determine whether the vibration isolation mass meets the requirements of the bearing capacity and the vibration isolation frequency band; if the requirements are met, the quasi-zero stiffness mechanism is debugged; otherwise, return to step S11;

[0025] The debugging method of the constant force mechanism comprises the following steps:

[0026] S21: Construct the constant force mechanism, so that the constant force mechanism is in an initial state; the initial state refers to a state in which the horizontal tension spring is at a free length when the two swing rods are hinged to the guide rod; in the initial state, the swing rod is in a horizontal state;

[0027] S22: Determine the basic dimensionless parameters, including the dimensionless pre-tension amount of the vertical tension spring the dimensionless projection length of the connecting rod in the vertical direction in the initial state the dimensionless length of the swing rod and the stiffness ratio α of the vertical tension spring and the horizontal tension spring and the displacement x from the initial state, in any x position, the rotation angle of the swing rod is θ x ;

[0028] S23: the application force f of the constant force mechanism is dimensionless, and a dimensionless application force is obtained

[0029]

[0030] the dimensionless application force to the first derivative is obtained, and the dimensionless parameter form is as follows: the approximate dimensionless stiffness is obtained the expression is as follows:

[0031]

[0032] in the formula,

[0033] the dimensionless parameter form in the above formula is as follows:

[0034]

[0035] S24: at the static equilibrium position, the stiffness is equal to zero and the second derivative of the stiffness is equal to zero, and the quasi-zero stiffness parameter condition is obtained and if the designed parameter value satisfies alpha is approximately equal to 0.25 and a constant zero stiffness characteristic can be obtained;

[0036] S25: the dimensionless stiffness curve of the constant force mechanism is drawn the curve is drawn, the application force applied to the constant force mechanism in the motion direction, when the quasi-zero stiffness mechanism is in the static equilibrium position; otherwise, return to step S21.

[0037] Further, when the quasi-zero stiffness mechanism is in the static equilibrium state, the connecting rod is in the vertical state; when the constant force mechanism is in the static equilibrium state, the connecting rod is in the vertical state.

[0038] Further, when the quasi-zero stiffness mechanism and the constant force mechanism are in the static equilibrium position the displacement of the quasi-zero stiffness mechanism and the constant force mechanism from the static equilibrium position is y, and the corresponding conversion relationship of the two coordinates is

[0039] Further, the rotation angle of the swing rod at any position x is theta x the limited expression is as follows:

[0040]

[0041] in the formula, denotes the dimensionless projection length of the connecting rod in the vertical direction, denotes the dimensionless length of the swing rod.

[0042] Further, by adjusting the connecting rod length l0, the constant force mechanism of the constant force under the action of the quasi-zero stiffness unit is in a static equilibrium position, and a compact horizontal direction quasi-zero stiffness vibration isolator with a single pair of swing rods can reach the static equilibrium position, and the horizontal direction quasi-zero stiffness is successfully adjusted.

[0043] Compared with the prior art, the present application has the following advantages:

[0044] (1) The first connecting rod unit and the second connecting rod unit are arranged in the vertical plane of the horizontal tension spring, based on the constraint characteristics of the swing rod to the connecting rod, the swing rod will not affect the quasi-zero stiffness mechanism, and horizontal vibration isolation can be performed. But the existing tension type vibration isolator based on the slider guide rail structure characteristics can only cooperate with the vertically arranged spring to constitute a quasi-zero stiffness vibration isolator, and is not suitable for horizontal vibration isolation. The present application provides a vibration isolator suitable for horizontal vibration reduction, which fills the gap in the prior art.

[0045] (2) The swing rod fixes the spring and the connecting rod, and the stretching of the connecting rod and the spring can be adjusted in cooperation with the swing of the swing rod, which simplifies the structure of the quasi-zero stiffness mechanism. Compared with the existing slider and guide rail matched vibration isolator, the number of required parts is reduced, the occupied space is reduced, the application range is wider, especially suitable for small space scenes with limited space, and the practicability of the vibration isolator is improved. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 The structure diagram of the horizontal direction quasi-zero stiffness vibration isolator provided by the present application is shown in the figure;

[0047] Figure 2 The structure diagram of the initial state of the quasi-zero stiffness mechanism provided by the present application is shown in the figure;

[0048] Figure 3 The structure diagram of the static equilibrium state of the quasi-zero stiffness mechanism provided by the present application is shown in the figure;

[0049] Figure 4 The structure diagram of the quasi-zero stiffness mechanism provided by the present application is shown in the figure;

[0050] Figure 5 The nonlinear quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present application is shown in the figure;

[0051] Figure 6 The force displacement curve corresponding to the nonlinear quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present application is shown in the figure;

[0052] Figure 7 Constant value quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present application;

[0053] Figure 8 Force displacement curve corresponding to the constant value quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present application;

[0054] Figure 9 Stiffness displacement curve of the constant force unit provided by the present application;

[0055] Figure 10 Force displacement curve of the constant force unit provided by the present application;

[0056] In the figure: 1, quasi-zero stiffness mechanism, 2, constant force mechanism, 11, swing rod, 12, connecting rod, 13, guide rod, 14, vertical tension spring, 15, horizontal tension spring. DETAILED DESCRIPTION

[0057] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0058] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0059] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0060] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0061] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0062] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0063] Example 1

[0064] like Figures 1-4 As shown, this embodiment provides a debugging method for a compact horizontal quasi-zero stiffness vibration isolator with a single pair of pendulum rods. The vibration isolator includes a quasi-zero stiffness mechanism 1 and a constant force mechanism 2 with identical structures. The quasi-zero stiffness mechanism 1 includes a first link unit, a second link unit, a guide rod 13, a vertical tension spring 14, and a horizontal tension spring 15.

[0065] The first linkage unit and the second linkage unit have the same structure and are symmetrically distributed on both sides of the horizontal tension spring 15. The first linkage unit includes a swing arm 11 and a connecting rod 12. One end of the swing arm 11 is hinged to the frame and the other end is hinged to the connecting rod 12. The other end of the connecting rod 12 is hinged to the guide rod 13. One end of the horizontal tension spring 15 is fixed to the frame and the other end is fixed to the guide rod 13.

[0066] The two ends of the vertical tension spring 14 are respectively connected to the hinge points of the rocker arm and the connecting rod in the first and second connecting rod units; the constant force mechanism 2 is used to apply a horizontal constant force to the guide rod 13 so that the quasi-zero stiffness mechanism 1 is in a static equilibrium state.

[0067] The debugging method for the quasi-zero stiffness mechanism 1 includes the following steps:

[0068] S11: Construct a quasi-zero stiffness mechanism 1, and put the quasi-zero stiffness mechanism 1 into its initial state; the initial state refers to the state in which the horizontal tension spring is at its free length when the two rocker arms are hinged to the guide rod; in the initial state, the rocker arms are in a horizontal state;

[0069] S12: Determine the basic dimensionless parameters, including the dimensionless pretension of the vertical tension spring 14. The dimensionless projected length of link 12 in the vertical direction in the initial state Dimensionless length of pendulum 11 And the stiffness ratio of vertical extension spring 14 and horizontal extension spring 15 α and the displacement x of the hinge end of guide rod 13 from the initial state, at any x position, the rotation angle of swing rod 11 is θ x ;

[0070] S13: Dimensionless the applied force f of zero-stiffness mechanism 1, and obtain the dimensionless applied force

[0071]

[0072] Dimensionless applied force To Take the first derivative, since the use of Obtain the approximate dimensionless stiffness Expression:

[0073]

[0074] In the formula:

[0075] The dimensionless parameter form in the above formula is as follows:

[0076]

[0077] S14: At the static equilibrium position, let the stiffness be equal to zero, and obtain the quasi-zero-stiffness parameter condition If the designed parameter values meet this parameter relationship, the nonlinear quasi-zero-stiffness characteristic can be obtained;

[0078] At the static equilibrium position, let the stiffness be equal to zero and the second derivative of the stiffness be equal to zero, and obtain the quasi-zero-stiffness parameter condition And If the designed parameter values meet 0 < α < 0.25 and The constant quasi-zero-stiffness characteristic can be obtained;

[0079] S15: Draw the Curve of the quasi-zero-stiffness mechanism, The applied force applied to the quasi-zero-stiffness mechanism in the direction of motion, when The quasi-zero-stiffness mechanism 1 is in a static equilibrium position, Divided by the acceleration of gravity is the vibration isolation mass, to determine whether it meets the demand for carrying capacity and vibration isolation frequency band; if it meets the demand, the debugging of the quasi-zero-stiffness mechanism 1 is completed; otherwise, return to step S11;

[0080] The debugging method of the constant force mechanism 2 includes the following steps:

[0081] S21: Construct the constant force mechanism 2, and make the constant force mechanism 2 in the initial state; the initial state refers to the state that the two swing rods are hinged with the guide rod and the horizontal tension spring is in the free length; in the initial state, the swing rod is in the horizontal state;

[0082] S22: Determine the basic dimensionless parameters, including the dimensionless pre-tension of the vertical tension spring 14 the dimensionless projection length of the connecting rod 12 in the vertical direction in the initial state the dimensionless length of the swing rod 11 and the stiffness ratio α of the vertical tension spring 14 and the horizontal tension spring 15 and the displacement x from the initial state, in any x position, the rotation angle of the swing rod 11 is θ x ;

[0083] S23: Dimensionless the applied force f of the constant force mechanism 2, and obtain the dimensionless applied force

[0084]

[0085] the dimensionless applied force the first-order derivative of is obtained, and the first-order derivative of the approximate dimensionless stiffness expression is obtained:

[0086]

[0087] In the formula:

[0088] The dimensionless parameter form in the above formula is as follows:

[0089]

[0090] S24: In the static equilibrium position, make the stiffness equal to zero and the second-order derivative of the stiffness equal to zero, and obtain the quasi-zero stiffness parameter condition and If the designed parameter value satisfies α≈0.25 and the constant zero stiffness characteristic can be obtained;

[0091] S25: Draw the curve of the constant force mechanism, is the applied force applied to the constant force mechanism in the movement direction, when the quasi-zero stiffness mechanism 1 is in the static equilibrium position; otherwise, return to step S21.

[0092] A first and second linkage unit are arranged in the vertical plane of a horizontal tension spring. Based on the constraint characteristics of the pendulum on the linkage, the pendulum will not affect the alignment of the zero-stiffness mechanism, thus enabling horizontal vibration isolation. However, existing tension vibration isolators, based on the characteristics of the slider guide structure, can only be used with vertically arranged springs to form quasi-zero-stiffness vibration isolators, and are not suitable for horizontal vibration isolation. This paper provides a vibration isolator that can be used for horizontal vibration reduction, filling the gap in the existing technology.

[0093] In this embodiment, in step S3, the basic dimensionless parameter satisfies the conditions 0 < α < 0.25 and At that time, the quasi-zero stiffness mechanism 1 has a constant quasi-zero stiffness characteristic.

[0094] The basic dimensionless parameters satisfy the conditions At that time, the quasi-zero stiffness mechanism 1 has nonlinear quasi-zero stiffness characteristics, such as Figure 5 and Figure 6 As shown, it can be calculated according to the quasi-zero stiffness condition. The nonlinear quasi-zero stiffness can be obtained, and the corresponding stiffness and force-displacement curves can be plotted.

[0095] When the design parameters satisfy the conditions 0 < α < 0.25 and At that time, the quasi-zero stiffness mechanism 1 has a constant quasi-zero stiffness characteristic. For example... Figure 7 and Figure 8 As shown, based on the fundamental dimensionless parameter, according to α < 0.25 and α → 0.25 and The constant quasi-zero stiffness can be obtained, and the stiffness and force-displacement curves can be plotted.

[0096] In this embodiment, when the quasi-zero stiffness mechanism 1 is in a static equilibrium state, the connecting rod is in a vertical state; when the constant force mechanism 2 is in a static equilibrium state, the connecting rod is in a vertical state.

[0097] Specifically, such as Figure 2 As shown, in the initial state of the quasi-zero stiffness mechanism, the first and second linkage units have identical structures. The lengths of the pendulum and connecting rod in both units are the same, and one end of the pendulum is fixed to one end face of the frame, making the structure symmetrical. The length of the pendulum is b, and the projected length of the connecting rod in the vertical direction is a. As point O of the hinge position between the connecting rod 12 and the guide rod 13 moves to the left, when the connecting rod is in a vertical state, the quasi-zero stiffness mechanism reaches its static equilibrium position. The applied force f at this time is the rated load of the vibration isolator.

[0098] In this embodiment, the constant force of the constant force mechanism is achieved by adjusting the connecting rod length l0. Under the action, the quasi-zero stiffness unit is in a static equilibrium position. Only a compact horizontal quasi-zero stiffness vibration isolator with a single pair of pendulum rods can reach the static equilibrium position, and the horizontal quasi-zero stiffness is successfully adjusted.

[0099] Specifically, methods for achieving quasi-zero stiffness in quasi-zero stiffness vibration isolators include:

[0100]

[0101] force right Differentiation, because it uses Approximate stiffness can be obtained:

[0102]

[0103] The dimensionless parameter in the above formula is in the following form:

[0104]

[0105] When the quasi-zero stiffness mechanism 1 and the constant force mechanism 2 are in static equilibrium position The displacement of quasi-zero stiffness mechanism 1 and constant force mechanism 2 from their static equilibrium positions is y. The corresponding transformation relationship between the two coordinates is as follows: Where θ x The equation is limited to:

[0106]

[0107] Setting the stiffness and its second derivative to zero at the static equilibrium position, two quasi-zero stiffness conditions can be approximately derived:

[0108]

[0109] In the initial state, the distance from the initial position O to the right end of the pendulum along the direction of motion is h. The distance from the initial position O to the static equilibrium position is h+h. c , where h c This refers to the horizontal displacement of the right end of the pendulum caused by the pendulum's oscillation from its initial position to its static equilibrium position. The horizontal tension spring has a stiffness of k2, providing the positive stiffness portion for constructing quasi-zero stiffness. The vertical tension spring has a stiffness of k1, which, in conjunction with the connecting rod, provides the negative stiffness portion for constructing quasi-zero stiffness, where δ is the pre-tension of the vertical tension spring in its initial state, and f... h This is the tension force of a vertically stretched spring in the vertical direction. The positive and negative stiffness structures are connected in parallel to achieve quasi-zero stiffness characteristics in the horizontal direction. The displacement from the initial state is x, and the displacement from the static equilibrium position is y. At the static equilibrium position, the rotation angle of the pendulum is θ, as shown... Figure 3 As shown. At any x position, the rotation angle of the pendulum is θ. x ,like Figure 4 As shown.

[0110] To analyze the structural parameter characteristics, the applied force f and its expression are transformed into a dimensionless stiffening formula (1), resulting in a dimensionless applied force. Expression, evaluate expression right The first derivative yields the dimensionless stiffness. See formula (2); formula (3) is a dimensionless parametric expression; at the static equilibrium position, let the dimensionless stiffness... Equal to zero, let stiffness The second derivative of the equation is equal to zero, and the parameter conditions for obtaining the quasi-zero stiffness characteristics are given in formulas (4) and (5). With formulas (4) and (5) as the basic conditions, the nonlinear quasi-zero stiffness characteristics and constant quasi-zero stiffness characteristics in the motion direction can be obtained.

[0111] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method of commissioning a compact horizontally oriented quasi-zero stiffness vibration isolator of single pair of swing link configuration, characterized by, The vibration isolator comprises a quasi-zero stiffness mechanism (1) and a constant force mechanism (2) with the same structure, the quasi-zero stiffness mechanism (1) comprising a first linkage unit, a second linkage unit, a guide rod (13), a vertical tension spring (14) and a horizontal tension spring (15); The first linkage unit and the second linkage unit have the same structure and are symmetrically distributed on both sides of the horizontal tension spring (15), the first linkage unit comprising a swing rod (11) and a linkage rod (12), one end of the swing rod (11) being hinged to a rack, the other end being hinged to the linkage rod (12), the other end of the linkage rod (12) being hinged to the guide rod (13), one end of the horizontal tension spring (15) being fixed to the rack, the other end being fixed to the guide rod (13); Both ends of the vertical tension spring (14) are connected to the hinged points of the swing rod and the linkage rod in the first linkage unit and the second linkage unit, respectively; the constant force mechanism (2) is used to apply a horizontal constant force to the guide rod (13), so that the quasi-zero stiffness mechanism (1) is in a static equilibrium state; The debugging method of the quasi-zero stiffness mechanism (1) comprises the following steps: S11: constructing the quasi-zero stiffness mechanism (1) so that the quasi-zero stiffness mechanism (1) is in an initial state; the initial state refers to a state in which the horizontal tension spring is at a free length when the two swing rods are hinged to the guide rod; in the initial state, the swing rod is in a horizontal state; S12: determining base dimensionless parameters, including dimensionless pre-tension of the vertical tension spring (14) dimensionless projected length of the connecting rod (12) in the vertical direction in the initial state dimensionless length of the swing rod (11) and the ratio of stiffness a of the vertical tension spring (14) and the horizontal tension spring (15) and the displacement x of the articulated end of the guide rod (13) from the initial state, at any x position, the rotation angle of the swing rod (11) is Q x ; S13: non-dimensionalize the applied force f of the alignment zero-stiffness mechanism (1) to obtain a non-dimensionalized applied force Expression: Dimensionless applied force To Take the first derivative, since the use of Obtain an approximate dimensionless stiffness Expression: In the formulae: The dimensionless parameter form in the above formula is as follows: S14: At the static equilibrium position, let the stiffness equal to zero, obtain the quasi-zero stiffness parameter condition If the parameter value of the design satisfies this parameter relationship, the quasi-zero stiffness mechanism obtains the nonlinear quasi-zero stiffness characteristic; At the static equilibrium position, the quasi-zero stiffness parameter conditions are obtained by setting the stiffness equal to zero and the second derivative of the stiffness equal to zero and If the designed parameter values satisfy 0 < α < 0.25 and The quasi-zero stiffness mechanism obtains a constant quasi-zero stiffness characteristic; S15: draw the curve of the quasi-zero stiffness mechanism , for the application force applied to the quasi-zero stiffness mechanism in the direction of motion, when the quasi-zero stiffness mechanism (1) is in a static equilibrium position, divide by the gravitational acceleration to obtain the isolation mass, determine whether it meets the requirements of the carrying capacity and isolation frequency band at this time; if it meets the requirements, complete the debugging of the quasi-zero stiffness mechanism (1); otherwise, return to step S11; The constant force mechanism (2) has the same structure as the quasi-zero stiffness mechanism (1) and is oppositely arranged, and the debugging method of the constant force mechanism (2) comprises the following steps: S21: constructing the constant force mechanism (2) so that the constant force mechanism (2) is in an initial state; the initial state refers to a state in which the horizontal tension spring is at a free length when the two swing rods are hinged to the guide rod; in the initial state, the swing rod is in a horizontal state; S22: determining base dimensionless parameters, including dimensionless pre-tension of the vertical tension spring (14) dimensionless projected length of the connecting rod (12) in the vertical direction in the initial state dimensionless length of the swing rod (11) and the stiffness ratio α of the vertical tension spring (14) and the horizontal tension spring (15) and the displacement x from the initial state, at any x position, the rotation angle of the swing rod (11) is θ x ; S23: The application force f of the constant force mechanism (2) is dimensionless, and a dimensionless application force is obtained Expression: Dimensionless applied force To Take the first derivative, since the use of Obtain an approximate dimensionless stiffness Expression: In the formulae: The dimensionless parameter form in the above formula is as follows: S24: At the static equilibrium position, the stiffness is equal to zero and the second derivative of the stiffness is equal to zero, the quasi-zero stiffness parameter conditions are obtained and If the parameter values of the design satisfy α≈0.25 and The constant force mechanism obtains constant zero stiffness characteristics; S25: Draw a constant force mechanism Curve graph For the applied force to be applied to a constant force mechanism in the direction of motion, when When the zero-stiffness mechanism (1) is in static equilibrium, otherwise, return to step S21.

2. The tuning method of a compact horizontally oriented quasi-zero stiffness vibration isolator of single pair of swing link configuration according to claim 1, wherein, When the quasi-zero stiffness mechanism (1) is in a static equilibrium state, the linkage rod is in a vertical state; when the constant force mechanism (2) is in a static equilibrium state, the linkage rod is in a vertical state.

3. The tuning method of a compact horizontally oriented quasi-zero stiffness vibration isolator of single pair of swing link configuration according to claim 2, wherein, Quasi-zero stiffness mechanism (1) and constant force mechanism (2) are in a static equilibrium position The displacement of the quasi-zero stiffness mechanism (1) and constant force mechanism (2) from the static equilibrium position is y, and the corresponding conversion relationship of the two coordinates is 4. The tuning method of a compact horizontally oriented quasi-zero stiffness vibration isolator with a single pair of swing link configuration according to claim 1, wherein The rotation angle of the swing lever (11) at any position x is θ x The defining expression is: wherein denotes the dimensionless projected length of the connecting rod (12) in the vertical direction, denotes the dimensionless length of the swing lever (11).

5. The tuning method of a compact horizontally oriented quasi-zero stiffness vibration isolator of single pair of swing link configuration according to claim 1, characterized in that, By adjusting the length of the connecting rod l0, the constant force mechanism is in static equilibrium position under the action of the constant force A compact horizontal quasi-zero stiffness vibration isolator with a single pair of swing rods is in static equilibrium position, and horizontal quasi-zero stiffness adjustment is successful.

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