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

Abstract

The invention relates to a debugging method of a compact horizontal quasi-zero stiffness vibration isolator constructed by a single swing rod, 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 swing rod, a connecting rod, a guide rod, a vertical extension spring and a horizontal extension spring; one end of the swing rod is hinged to the rack, and the other end of the swing rod is hinged to the connecting rod; one end of the horizontal extension spring is fixed to the rack, the other end of the horizontal extension spring is fixed to the guide rod, and one end of the vertical extension spring is connected with the hinge point of the swing rod and the connecting rod. Compared with the prior art, the vibration isolator has the advantages of being simple in structure, few in used parts, small in occupied space, capable of achieving horizontal vibration reduction 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 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. A nonlinear vibration isolation system 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 a 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 vertical tensile spring, a connecting rod, a slider, and a guide rail. It 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 left-right symmetry. 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 causes the vertical tensile spring to produce negative stiffness. This structure is relatively complex, occupies a large space, and is not suitable for some space-limited applications.

[0006] In summary, the existing quasi-zero stiffness vibration isolation structure 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 part-less quasi-zero stiffness vibration isolator to effectively expand the application scenarios of quasi-zero stiffness vibration isolators. SUMMARY

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

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

[0009] A debugging method for a single swing rod structured compact horizontal direction quasi-zero-stiffness vibration isolator, comprising a quasi-zero-stiffness mechanism and a constant force mechanism with the same structure, the quasi-zero-stiffness mechanism comprising a swing rod, a connecting rod, a guide rod, a vertical tension spring, and a horizontal tension spring;

[0010] One end of the swing rod is hinged to a rack, one end of the horizontal tension spring is fixed to the rack, and the other end is fixed to the guide rod, one end of the connecting rod is hinged to the swing rod, and the other end is hinged to the guide rod;

[0011] One end of the vertical tension spring is connected to the hinge joint of the connecting rod and the swing rod, and the other end is fixed to the rack, and the guide rod and the horizontal tension spring are both arranged horizontally; 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 of 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 swing rod is 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 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 ; take the first order derivative, since obtain the approximate dimensionless stiffness Expression of the formula:

[0018]

[0019] In the formula:

[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 obtain the quasi-zero stiffness parameter condition If the designed parameter values satisfy the parameter relationship, the quasi-zero stiffness mechanism obtains the nonlinear quasi-zero stiffness characteristic;

[0023] At the static equilibrium position, let the stiffness be equal to zero and the second-order derivative of the stiffness be equal to zero, and obtain the quasi-zero stiffness parameter condition And If the designed parameter values satisfy 0 < α < 1 and The quasi-zero stiffness mechanism obtains the constant value quasi-zero stiffness characteristic;

[0024] S15: Draw the f Q -x curve of the quasi-zero stiffness mechanism, is 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 demand for the bearing capacity and the vibration isolation frequency band is met at this time; if the demand is met, the debugging of the quasi-zero stiffness mechanism is completed; otherwise, return to step S11;

[0025] The constant force mechanism has the same structure as the quasi-zero stiffness mechanism and is oppositely arranged, and 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, and the initial state refers to a state in which the horizontal tension spring is in a free length state when the swing rod is hinged to the guide rod; in the initial state, the swing rod is in a horizontal state;

[0027] S22: Determine the basic dimensionless parameter, 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 of the guide rod from the initial state, in any x position, the rotation angle of the swing rod is θ x ;

[0028] S23: Dimensionlessly transform the applied force f of the constant force mechanism to obtain the dimensionless applied force. The expression:

[0029]

[0030] Dimensionless application force right Find the first derivative, because it uses Obtain approximately dimensionless stiffness The expression:

[0031]

[0032] In the formula:

[0033] The dimensionless parameter in the above formula has the following form:

[0034]

[0035] S24: At the static equilibrium position, let the stiffness be zero and the second derivative of the stiffness be zero to obtain the quasi-zero stiffness parameter condition. and If the designed parameter values ​​satisfy α≈1 and A constant force mechanism achieves constant zero stiffness characteristics

[0036] S25: Draw a constant force mechanism Curve graph The applied force is the force applied to a constant force mechanism in the direction of motion. If the zero-stiffness mechanism is in static equilibrium, then return to step S21.

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

[0038] Furthermore, when the quasi-zero stiffness mechanism and the constant force mechanism are in static equilibrium positions... The displacement of the quasi-zero stiffness mechanism and the constant force mechanism from their static equilibrium positions is y, and the corresponding transformation relationship between the two coordinates is as follows:

[0039] Furthermore, the rotation angle of the pendulum at any position x is θ. x The qualified expression is:

[0040]

[0041] In the formula, This represents the dimensionless projected length of the link in the vertical direction in the initial state. This represents the dimensionless length of the pendulum rod.

[0042] Furthermore, by adjusting the connecting rod length l0, the constant force of the constant force mechanism is achieved. Under the action, the quasi-zero stiffness unit is in a static equilibrium position. A compact horizontal quasi-zero stiffness vibration isolator with a single pendulum structure has reached a static equilibrium position, and the horizontal quasi-zero stiffness has been successfully adjusted.

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

[0044] (1) In this solution, the rotatable swing arm and the connecting rod can be rotatably connected, which can realize the construction of positive stiffness and negative stiffness mechanism, simplifying the structure of quasi-zero stiffness mechanism. Compared with the existing vibration isolation structure with slider and guide rail, it reduces the number of required parts, reduces the space occupied, and has a wider range of applications, especially suitable for small space scenarios with limited space, thus improving the practicality of vibration isolation structure.

[0045] (2) In this solution, a hinged connecting rod and a guide rod are set in the vertical plane of the horizontal tension spring. In conjunction with the vertical tension spring in the vertical direction, based on the constraint characteristics of the pendulum rod on the connecting rod, the pendulum rod will not affect the alignment of the zero stiffness mechanism, enabling the shock absorber to perform horizontal vibration isolation. However, existing tension-type vibration isolators, based on the characteristics of the slider guide rail structure, can only be used with vertically set springs to form quasi-zero stiffness vibration isolators, and are not suitable for horizontal vibration isolation. This solution provides a vibration isolator that can be used for horizontal vibration reduction, filling the gap in the existing technology. Attached Figure Description

[0046] Figure 1 A schematic diagram of the horizontal quasi-zero stiffness vibration isolation structure provided by the present invention;

[0047] Figure 2 A schematic diagram of the initial state of the quasi-zero stiffness mechanism provided by the present invention;

[0048] Figure 3 A schematic diagram of the static equilibrium state of the quasi-zero stiffness mechanism provided by the present invention;

[0049] Figure 4 A schematic diagram of the quasi-zero stiffness mechanism at any position provided by the present invention;

[0050] Figure 5 The nonlinear quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present invention;

[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 invention;

[0052] Figure 7 The constant quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present invention;

[0053] Figure 8 The force-displacement curve corresponding to the constant quasi-zero stiffness curve of the quasi-zero stiffness mechanism provided by the present invention;

[0054] Figure 9 Stiffness-displacement curves of the constant force unit provided by the present invention;

[0055] Figure 10 Force-displacement curves of the constant force unit provided by this invention;

[0056] In the diagram: 1. Quasi-zero stiffness mechanism, 2. Constant force mechanism, 11. Pendulum rod, 12. Connecting rod, 13. Guide rod, 14. Vertical tension spring, 15. Horizontal tension spring. Detailed Implementation

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

[0058] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0059] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0060] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[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 to 4 As shown, this embodiment provides

[0065] A method for debugging a compact horizontal quasi-zero stiffness vibration isolator with a single pendulum rod structure includes a quasi-zero stiffness mechanism 1 and a constant force mechanism 2 with identical structures. The quasi-zero stiffness mechanism 1 includes a pendulum rod 11, a connecting rod 12, a guide rod 13, a vertical tension spring 14, and a horizontal tension spring 15.

[0066] One end of the swing arm 11 is hinged to the frame, one end of the horizontal tension spring 15 is fixed to the frame, and the other end is fixed to the guide rod 13. One end of the connecting rod 12 is hinged to the swing arm 11, and the other end is hinged to the guide rod 13.

[0067] One end of the vertical tension spring 14 is connected to the hinge point of the connecting rod 12 and the swing rod 11, and the other end is fixed on the frame. The guide rod 13 and the horizontal tension spring 15 are both set horizontally. 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.

[0068] The debugging method for the quasi-zero stiffness mechanism 1 includes the following steps:

[0069] 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 rocker arm and the guide rod are hinged; in the initial state, the rocker arm is in a horizontal state;

[0070] 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 The stiffness ratio α of the vertical tension spring 14 and the horizontal tension spring 15, and the displacement x of the guide rod 13 from the initial state, mean that at any position x, the rotation angle of the pendulum rod 11 is θ. x ;

[0071] S13: Dimensionlessly transform the applied force f of the zero-stiffness mechanism 1 to obtain the dimensionless applied force. The expression for:

[0072]

[0073] Dimensionless application force right Find the first derivative, because it uses Obtain approximately dimensionless stiffness The expression:

[0074]

[0075] In the formula:

[0076] The dimensionless parameter in the above formula has the following form:

[0077]

[0078] S14: At the static equilibrium position, set the stiffness to zero to obtain the quasi-zero stiffness parameter condition. If the designed parameter values ​​satisfy this parameter relationship, the quasi-zero stiffness mechanism obtains nonlinear quasi-zero stiffness characteristics;

[0079] At the static equilibrium position, setting the stiffness to zero and the second derivative of the stiffness to zero, we obtain the quasi-zero stiffness parameter condition. and If the designed parameter values ​​satisfy 0 < α < 1 and Quasi-zero stiffness mechanisms achieve constant quasi-zero stiffness characteristics;

[0080] S15: Draw the f of the quasi-zero stiffness mechanism. Q -x curve graph For the applied force to be applied to the quasi-zero stiffness mechanism in the direction of motion, when The zero-stiffness mechanism 1 is in static equilibrium. Divide the vibration isolation mass by the gravitational acceleration and determine whether it meets the requirements of bearing capacity and vibration isolation frequency band; if it meets the requirements, complete the debugging of quasi-zero stiffness mechanism 1; otherwise, return to step S11.

[0081] The constant force mechanism 2 has the same structure as the quasi-zero stiffness mechanism 1 and is set opposite to it. The debugging method of the constant force mechanism 2 includes the following steps:

[0082] S21: Construct constant force mechanism 2, so that constant force mechanism 2 is in the initial state. The initial state refers to the state in which the horizontal tension spring is in the free length when the rocker arm and the guide rod are hinged. In the initial state, the rocker arm is in the horizontal state.

[0083] S22: Determine the basic dimensionless parameters, including the dimensionless pretension of the vertical tension spring. The dimensionless projected length of the link in the vertical direction in the initial state dimensionless length of the pendulum Given the stiffness ratio α of the vertical tension spring and the horizontal tension spring, and the displacement x of the guide rod from its initial state, the rotation angle of the pendulum rod at any position x is θ. x ;

[0084] S23: Dimensionlessly transform the applied force f of the constant force mechanism 2 to obtain the dimensionless applied force. The expression:

[0085]

[0086] Dimensionless application force right Find the first derivative, because it uses Obtain approximately dimensionless stiffness The expression:

[0087]

[0088] In the formula:

[0089] The dimensionless parameter in the above formula has the following form:

[0090]

[0091] S24: At the static equilibrium position, let the stiffness be zero and the second derivative of the stiffness be zero to obtain the quasi-zero stiffness parameter condition. and If the designed parameter values ​​satisfy α≈1 and A constant force mechanism achieves constant zero stiffness characteristics

[0092] S25: Draw a constant force mechanism Curve graph The applied force is the force applied to a constant force mechanism in the direction of motion. When the zero-stiffness mechanism 1 is in static equilibrium, otherwise, return to step S21.

[0093] By rotatably connecting the rotatable lever and the connecting rod, positive and negative stiffness mechanisms can be constructed, simplifying the structure of quasi-zero stiffness mechanisms. Compared with existing vibration isolation structures that use sliders and guide rails, this reduces the number of required parts, reduces the space occupied, and has a wider range of applications, especially suitable for small space scenarios with limited space, thus improving the practicality of vibration isolation structures.

[0094] In this embodiment, the basic dimensionless parameter satisfies the condition. 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] The fundamental dimensionless parameters satisfy the conditions 0 < α < 1 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 parameters, according to 0 < α < 1 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 of the constant force mechanism is in a vertical state.

[0097] Specifically, such as Figure 2 As shown, in the initial state of the quasi-zero stiffness mechanism, the length of the pendulum is b, and the projection 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 the vertical state, the quasi-zero stiffness mechanism reaches the 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. A compact horizontal quasi-zero stiffness vibration isolator with a single pendulum structure has reached a static equilibrium position, and the horizontal quasi-zero stiffness has been successfully adjusted.

[0099] A hinged connecting rod and guide rod are installed in the vertical plane of the horizontal tension spring. Combined with the vertical tension spring, and based on the constraint characteristics of the pendulum rod on the connecting rod, the pendulum rod will not affect the alignment of the zero-stiffness mechanism, enabling the shock absorber to perform horizontal vibration isolation. However, existing tension-type vibration isolators, based on the characteristics of the slider guide rail structure, can only form quasi-zero-stiffness vibration isolators with vertically positioned springs, and are not suitable for horizontal vibration isolation. This solution provides a vibration isolator applicable to horizontal vibration reduction, filling a gap in the existing technology.

[0100] Specifically, the steps for determining the nonlinear quasi-zero stiffness characteristics or constant quasi-zero stiffness characteristics of a quasi-zero stiffness isolation structure include:

[0101] Specific methods for achieving quasi-zero stiffness in quasi-zero stiffness vibration isolation structures:

[0102]

[0103] force right Differentiation, because it uses Approximate stiffness can be obtained:

[0104]

[0105] The dimensionless parameter in the above formula has the following form:

[0106]

[0107] Quasi-zero stiffness mechanism 1 and constant force mechanism 2 are in static equilibrium. The transformation relationship between the two coordinates is as follows: θ x Limited to the equation:

[0108]

[0109] Setting the stiffness and its second derivative to zero at the static equilibrium position, two quasi-zero stiffness conditions can be approximately derived:

[0110]

[0111] In the initial state, the distance from the initial position O to the right end of the swing arm 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 its oscillation from the initial position to the static equilibrium position. The horizontal vertical 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. For example... Figure 3 and Figure 4 As shown, where δ is the pretension of the vertical tension spring in its initial state, and f h This refers to the tension force of a vertically stretched spring in the vertical direction. The parallel connection of positive and negative stiffness structures achieves 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. At any x position, the rotation angle of the pendulum is θ. x.

[0112] 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.

[0113] 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 for debugging a compact horizontal quasi-zero stiffness vibration isolator with a single pendulum rod structure, characterized in that, It includes a quasi-zero stiffness mechanism (1) and a constant force mechanism (2) with the same structure. The quasi-zero stiffness mechanism (1) includes a rocker arm (11), a connecting rod (12), a guide rod (13), a vertical tension spring (14), and a horizontal tension spring (15). One end of the swing arm (11) is hinged to the frame, one end of the horizontal tension spring (15) is fixed to the frame, and the other end is fixed to the guide rod (13). One end of the connecting rod (12) is hinged to the swing arm (11), and the other end is hinged to the guide rod (13). One end of the vertical tension spring (14) is connected to the hinge point of the connecting rod (12) and the swing rod (11), and the other end is fixed on the frame. The guide rod (13) and the horizontal tension spring (15) are both set horizontally. 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) includes the following steps: S11: Construct a quasi-zero stiffness mechanism (1) to 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 rocker arm is hinged to the guide rod; in the initial state, the rocker arm is in a horizontal state; S12: Determine the basic dimensionless parameters, including the dimensionless pretension of the vertical tension spring (14). The dimensionless projection length of the link (12) in the vertical direction in the initial state dimensionless length of the pendulum (11) The stiffness ratio α of the vertical tension spring (14) and the horizontal tension spring (15), and the displacement x of the guide rod (13) from the initial state, at any x position, the rotation angle of the pendulum rod (11) is θ. x ; S13: Dimensionlessly transform the applied force f of the zero-stiffness mechanism (1) to obtain the dimensionless applied force. The expression for: Dimensionless application force right Find the first derivative, because it uses Obtain approximately dimensionless stiffness The expression: In the formula: The dimensionless parameter in the above formula has the following form: S14: At the static equilibrium position, set the stiffness to zero to obtain the quasi-zero stiffness parameter condition. If the designed parameter values ​​satisfy this parameter relationship, the quasi-zero stiffness mechanism obtains nonlinear quasi-zero stiffness characteristics; At the static equilibrium position, setting the stiffness to zero and the second derivative of the stiffness to zero, we obtain the quasi-zero stiffness parameter condition. and If the designed parameter values ​​satisfy 0 < α < 1 and Quasi-zero stiffness mechanisms achieve constant quasi-zero stiffness characteristics; S15: Draw the f of the quasi-zero stiffness mechanism. Q -x curve graph For the applied force to be applied to the quasi-zero stiffness mechanism in the direction of motion, when The zero-stiffness mechanism (1) is in static equilibrium. Divide the vibration isolation mass by the gravitational acceleration and determine whether it meets the requirements of bearing capacity and vibration isolation frequency band; 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 arranged opposite to it. The debugging method of the constant force mechanism (2) includes the following steps: S21: Construct a constant force mechanism (2) to put the constant force mechanism (2) into its initial state. The initial state refers to the state where the horizontal tension spring is at its free length when the rocker arm is hinged to the guide rod. In the initial state, the rocker arm is in a horizontal state. S22: Determine the basic dimensionless parameters, including the dimensionless pretension of the vertical tension spring. The dimensionless projected length of the link in the vertical direction in the initial state dimensionless length of the pendulum Given the stiffness ratio α of the vertical tension spring and the horizontal tension spring, and the displacement x of the guide rod from its initial state, the rotation angle of the pendulum rod at any position x is θ. x ; S23: Dimensionless application force f of constant force mechanism (2) is obtained to obtain dimensionless application force. The expression: Dimensionless application force right Find the first derivative, because it uses Obtain approximately dimensionless stiffness The expression: In the formula: The dimensionless parameter in the above formula has the following form: S24: At the static equilibrium position, let the stiffness be zero and the second derivative of the stiffness be zero to obtain the quasi-zero stiffness parameter condition. and If the designed parameter values ​​satisfy α≈1 and A constant force mechanism achieves constant zero stiffness characteristics S25: Draw a constant force mechanism Curve graph The applied force is the force applied to a constant force mechanism in the direction of motion. When the zero-stiffness mechanism (1) is in static equilibrium, otherwise, return to step S21.

2. The debugging method for a compact horizontal quasi-zero stiffness vibration isolator with a single pendulum rod structure according to claim 1, characterized in that, When the quasi-zero stiffness mechanism (1) is in static equilibrium, the connecting rod (12) is in a vertical state. When the constant force mechanism (2) is in static equilibrium, the connecting rod of the constant force mechanism (2) is in a vertical state.

3. The debugging method for a compact horizontal quasi-zero stiffness vibration isolator with a single pendulum rod structure according to claim 1, characterized in that, When the quasi-zero stiffness mechanism (1) and the constant force mechanism (2) are in static equilibrium position The displacement of the quasi-zero stiffness mechanism (1) and the constant force mechanism (2) from their static equilibrium positions is y, and the corresponding transformation relationship between the two coordinates is as follows:

4. The debugging method of a compact horizontal quasi-zero stiffness vibration isolator with a single pendulum rod structure according to claim 1, characterized in that, The rotation angle of the pendulum (11) at any position x is θ x The qualified expression is: In the formula, This represents the dimensionless projection length of link (12) in the vertical direction in the initial state. This represents the dimensionless length of the pendulum rod (11).

5. The debugging method for a compact horizontal quasi-zero stiffness vibration isolator with a single pendulum rod structure according to claim 1, characterized in that, By adjusting the connecting rod length l0, the constant force of the constant force mechanism is achieved. Under the action, the quasi-zero stiffness unit is in a static equilibrium position. A compact horizontal quasi-zero stiffness vibration isolator with a single pendulum structure has reached a static equilibrium position, and the horizontal quasi-zero stiffness has been successfully adjusted.

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