A constant-value quasi-zero stiffness vibration isolation structure based on horizontal tension spring and its debugging method

Abstract

The present invention proposes a constant quasi-zero stiffness vibration isolation structure and debugging method based on a horizontal tension spring, including a vertical spring, the vertical spring is arranged on a vertical spring guide rod, a vertical guide mechanism is movably arranged on the vertical spring guide rod, and a load-bearing mechanism is arranged on the vertical guide mechanism; negative stiffness structures are symmetrically arranged on both sides of the vertical guide mechanism, and the negative stiffness structure includes an inclined rod and a horizontal tension spring, one end of the inclined rod is hinged to the vertical guide mechanism, and the other end of the inclined rod is hinged to the horizontal guide mechanism, the horizontal guide mechanism is movably connected to the bracket, and the two horizontal guide mechanisms are connected by a horizontal tension spring. The present invention can obtain low-frequency vibration isolation characteristics with constant quasi-zero stiffness, solve the problem that the traditional quasi-zero stiffness vibration isolator has a cubic nonlinear stiffness, fails in low-frequency vibration isolation under large-amplitude excitation, and cannot withstand variable mass load vibration isolation, and the use of a tension spring can reduce friction resistance to obtain a lower starting vibration isolation frequency for practical applications.

Description

Technical Field

[0001] The invention relates to the technical field of quasi-zero stiffness vibration isolators, and in particular to a constant-value quasi-zero stiffness vibration isolation structure based on a horizontal tension spring and a debugging method. Background Art

[0002] Most existing quasi-zero stiffness vibration isolators have cubic nonlinear stiffness and are not suitable for large-amplitude excitation and variable mass load conditions. In order to solve the existing technical problems, the present invention proposes a constant-value quasi-zero stiffness vibration isolation structure and a debugging method.

[0003] Reference [1] --- [Thanh Danh Le, Kyoung Kwan Ahn, A vibration isolation system in low frequency excitation region using negative stiffness structure for vehicle seat, Journal of Sound and Vibration, 2011, 330, 6311-6335.] publicly studied a single pair of diagonal rod quasi-zero stiffness model, in which the negative stiffness generated by a pair of diagonal rods and a pair of compression springs is connected in parallel with the vertical spring (different from the structure of the present application) to construct a quasi-zero stiffness isolator, but it has cubic nonlinear stiffness, a narrow quasi-zero stiffness range near the static equilibrium point, and an increase in dynamic stiffness under large excitation conditions, resulting in failure of low-frequency vibration isolation (different from the effect of the present application, and the debugging method is also different). The parameter assumptions it adopts are that the parameter design method is complex and contains several inequalities, while this patent application only contains two simple debugging formulas, which is not convenient for design and application; the original length of the horizontal compression spring is used as a dimensionless basic parameter in its theoretical derivation process; the quasi-zero stiffness condition in which the stiffness expression is equal to zero at the static equilibrium point is adopted, and the number is 1; the quasi-zero stiffness characteristic is obtained only in a very narrow range near the static equilibrium point, and it has the mechanical characteristics of cubic nonlinear stiffness. When the position deviates far from the static equilibrium point, the dynamic stiffness increases instead of the quasi-zero characteristic. Under large excitation, due to the hard nonlinear stiffness characteristics, the vibration isolation frequency band will be reduced, which will lead to the failure of low-frequency vibration isolation.

[0004] Document [2] --- The invention patent with application number 202111347500.9 discloses a zero-stiffness vibration isolation structure and method composed of a single pair of diagonal rods with negative stiffness mechanism, which includes two transverse springs and a vertical spring, and the two transverse springs are adjusted by a pair of diagonal rods, and a compression spring is used to generate negative stiffness. There is a certain friction damping between the compression spring and the guide rod, which affects the low-frequency band of the vibration isolation frequency band, increases the starting vibration isolation frequency, and causes the low-frequency vibration isolation effect to deteriorate. Compared with this patent application, both have constant quasi-zero stiffness characteristics, but the structure and debugging method are completely different. Summary of the invention

[0005] Aiming at the technical problem that the existing quasi-zero stiffness vibration isolation structure has a narrow quasi-zero stiffness range near the static equilibrium point, the present invention proposes a constant quasi-zero stiffness vibration isolation structure based on a horizontal tension spring and a debugging method.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the present invention is implemented as follows: a constant quasi-zero stiffness vibration isolation structure based on a horizontal tension spring, including a vertical spring, the vertical spring is arranged on a vertical spring guide rod, a vertical guide mechanism is movably provided on the vertical spring guide rod, the vertical spring is arranged below the vertical guide mechanism, and a load-bearing mechanism is provided on the vertical guide mechanism; negative stiffness structures are symmetrically provided on both sides of the vertical guide mechanism, the negative stiffness structure includes an inclined rod and a horizontal tension spring, one end of the inclined rod is hinged to the vertical guide mechanism, the other end of the inclined rod is hinged to the horizontal guide mechanism, the horizontal guide mechanism is movably connected to the bracket, and the two horizontal guide mechanisms are connected by a horizontal tension spring.

[0007] Preferably, the vertical guiding mechanism comprises a vertical guide rod linear bearing, the upper part of the vertical spring guide rod is movably arranged in the vertical guide rod linear bearing, the upper part of the vertical spring is fixedly connected to the lower part of the vertical guide rod linear bearing; a load-bearing mechanism is fixed to the upper part of the vertical guide rod linear bearing.

[0008] Preferably, the load-bearing mechanism comprises a load-bearing plate, and the load-bearing plate is fixedly connected to the upper part of the vertical guide rod linear bearing of the vertical guide mechanism through a hollow tube.

[0009] Preferably, support connection blocks are symmetrically fixed on both sides of the vertical guide rod linear bearing, the support connection blocks are fixedly connected to the inclined rod hinge support, and the inclined rod hinge support is hinged to the inclined rod.

[0010] Preferably, the horizontal guiding mechanism includes a transverse guide rod, one end of which is movably arranged on a transverse guide rod linear bearing, and the transverse guide rod linear bearing is detachably connected to the bracket; the other end of the transverse guide rod is hinged to the oblique rod, and the other ends of the two transverse guide rods are respectively fixedly connected to the two ends of the horizontal tension spring.

[0011] Preferably, a radial bearing is fixed to the other end of the transverse guide rod, the radial bearing is hinged to the oblique rod through a pin, and the end of the horizontal tension spring is fixed on the pin.

[0012] Preferably, there are two horizontal tension springs, which are respectively arranged on both sides of the vertical spring guide rod.

[0013] Preferably, the bracket is fixed on a fixed plate, and a vertical spring guide rod support is provided in the center of the two brackets on the fixed plate, a vertical spring guide rod is fixed on the vertical spring guide rod support, and the lower part of the vertical spring is fixedly connected to the vertical spring guide rod support; the bracket is provided with a long central through hole and side holes, the central through hole matches the transverse guide rod linear bearing of the horizontal guide mechanism, and the transverse guide rod linear bearing is connected to the side hole through a positioning bolt.

[0014] A debugging method for a constant-value quasi-zero stiffness vibration isolation structure based on a horizontal tension spring, the steps of which are as follows:

[0015] (1) Draw a force diagram of the constant quasi-zero stiffness vibration isolation structure in the initial state to obtain the applied force:

[0016]

[0017] Among them, k1 is the stiffness of two horizontal tension springs equivalent to one tension spring, k2 represents the stiffness of the vertical spring, x is the displacement from the initial position, y is the displacement from the static equilibrium position; a is the horizontal component of the diagonal rod in the initial state; represents the pre-tension of the horizontal tension spring in the initial state; h is the distance from the intersection of the diagonal rods to the static equilibrium position in the initial state;

[0018] (2) The applied force f and its expression are dimensionless.

[0019]

[0020] in, The stiffness ratio of the horizontal extension spring to the vertical spring Intermediate variables And x=y+h;

[0021] (3) Using dimensionless applied forces For dimensionless displacement The first-order derivative can be used to obtain the dimensionless stiffness of the system.

[0022]

[0023] (4) In the static equilibrium position, the dimensionless stiffness Find the second derivative and make it equal to zero and let is equal to zero, we can get the parameter conditions of zero stiffness characteristic α=0.25 and

[0024] (5) The ratio α of the horizontal tension spring stiffness to the vertical spring stiffness satisfies 0<α<0.25, and in the initial state, the pre-stretching length δ of the horizontal tension spring is adjusted to twice the horizontal component a of the lower diagonal rod of the diagonal rod in the initial state, that is, δ=2a, and then adjusted to a constant value quasi-zero stiffness vibration isolation structure.

[0025] Preferably, the static equilibrium position is the position of the hinge point of the two oblique rods when the oblique rods are in a horizontal state.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: low-frequency vibration isolation characteristics with constant quasi-zero stiffness can be obtained, and the problems of traditional quasi-zero stiffness vibration isolators having cubic nonlinear stiffness, failing in low-frequency vibration isolation under large-amplitude excitation, and being unable to withstand variable mass load vibration isolation are solved. The use of a tension spring can reduce frictional resistance to obtain a lower starting vibration isolation frequency for practical applications.

[0027] Compared with the document [1], the parameter assumption adopted by the present invention is more intuitive and simpler; the inclined rod length adopted is a dimensionless basic parameter, which can obtain a simple and convenient constant quasi-zero stiffness debugging method; two quasi-zero stiffness conditions are adopted, the stiffness expression is equal to zero at the static equilibrium position and the second-order derivative of stiffness to displacement is equal to zero at the static equilibrium position, and the zero stiffness condition is obtained, α<0.25, δ=2a; and then the constant quasi-zero stiffness condition 0<α<0.25, δ=2a is obtained, which has a constant quasi-zero stiffness characteristic, and the constant quasi-zero stiffness characteristic can be obtained regardless of whether the position is far from or close to the static equilibrium position. Compared with the document [2], the present invention adopts a tension spring to generate negative stiffness. The tension spring does not need a guide rod, has no friction, has a simpler structure, and has better effect; the theoretical formula displayed by the present invention is completely different, especially the zero stiffness condition part is obviously different, and the effect achieved is also completely different. Therefore, the present invention shows innovations that are significantly different from the existing literature in terms of structural implementation, design method, and effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a structural schematic diagram of the present invention.

[0030] Figure 2 for Figure 1 The structural schematic diagram of the diagonal rod hinge support is shown.

[0031] Figure 3 for Figure 1 Schematic diagram of the structure of the support connecting block shown.

[0032] Figure 4 This is the assembly drawing of the transverse guide rod and the diagonal rod.

[0033] Figure 5 for Figure 4 Top view of the .

[0034] Figure 6 A schematic diagram of the structure of the bracket.

[0035] Figure 7 Schematic diagram of the quasi-zero stiffness model of the present invention, wherein (a) is a mechanical model and (b) is a horizontal tension spring.

[0036] Figure 8 It is a simulation schematic diagram of the present invention, wherein (a) is a stiffness displacement curve, and (b) is a force displacement curve.

[0037] In the figure, 1 is a fixed plate, 2 is a bracket, 3 is a transverse guide rod linear bearing, 4 is a transverse guide rod, 5 is a radial bearing, 6 is a pin shaft, 7 is an inclined rod, 8 is an inclined rod hinge support, 9 is a support connecting block, 10 is a vertical spring guide rod, 11 is a vertical spring, 12 is a hollow tube, 13 is a load plate, 14 is a vertical guide rod linear bearing, 15 is a horizontal tension spring, and 16 is a vertical spring guide rod support. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] like Figure 1As shown, a constant value quasi-zero stiffness vibration isolation structure based on a horizontal tension spring includes a vertical spring 11, which is a compression spring. The vertical spring 11 is arranged on a vertical spring guide rod 10. Under the action of a heavy object above, the vertical spring 11 is compressed and restored along the vertical spring guide rod 10. A vertical guide mechanism is movably arranged on the vertical spring guide rod 10, and a load-bearing mechanism is arranged on the vertical guide mechanism. The vertical spring 11 is arranged below the vertical guide mechanism. Under the action of the load-bearing mechanism, the vertical guide mechanism moves up and down along the vertical spring guide rod 10, thereby compressing the vertical spring 11. Negative stiffness structures are symmetrically arranged on both sides of the vertical guide mechanism, and the negative stiffness structures include an inclined rod 7, one end of the inclined rod 7 is hinged to the vertical guide mechanism, and the other end of the inclined rod 7 is hinged to the horizontal guide mechanism. The horizontal guide mechanism is movably connected to the bracket 2, and the horizontal guide mechanism can be adjusted up and down relative to the bracket 2. Under the action of the vertical guide mechanism, the inclined rod 7 pushes the horizontal guide mechanism to move horizontally. The two horizontal guide mechanisms are connected by a horizontal tension spring 15, and the horizontal tension spring 15 is a tension spring that stretches the two horizontal guide mechanisms. The number of the horizontal tension springs 15 is two and they are respectively arranged on both sides of the vertical spring guide rod 10, thereby ensuring the symmetrical arrangement of the two diagonal rods. The diagonal rod 7 and the transverse spring 15 constitute a negative stiffness structure. The negative stiffness structure is connected in parallel with the positive stiffness structure of the vertical spring 11. Since the positive and negative stiffnesses cancel each other out, a quasi-zero stiffness characteristic can be obtained, thereby reducing the starting vibration isolation frequency. Near the static balance point (the static balance point is where a pair of diagonal rods are in a horizontal state), a constant quasi-zero stiffness can be obtained by a debugging method.

[0040] As a further implementation, the vertical guide mechanism includes a vertical guide rod linear bearing 14, the upper part of the vertical spring guide rod 10 is movably arranged in the vertical guide rod linear bearing 14, and the upper part of the vertical spring 11 is fixedly connected to the lower part of the vertical guide rod linear bearing 14. The bracket 2 is fixed on the fixed plate 1, and a vertical spring guide rod support 16 is provided in the center of the two brackets 2 on the fixed plate 1, so that the brackets are symmetrically arranged on both sides of the vertical spring guide rod 10, ensuring that the horizontal guide mechanism is symmetrically arranged on both sides of the vertical spring 11. The vertical spring guide rod support 16 is fixedly provided with the vertical spring guide rod 10, and the lower part of the vertical spring 11 is fixedly connected to the vertical spring guide rod support 16. The function of the vertical spring guide rod support 16 is to fix the vertical spring guide rod 10, ensuring that the vertical spring moves vertically on the vertical spring guide rod 10.

[0041] As a further embodiment, a load-bearing mechanism is fixed to the upper part of the vertical guide rod linear bearing 14, and the load-bearing mechanism includes a load-bearing plate 13, and the load-bearing plate 13 is used to bear heavy objects, and the load-bearing plate 13 is fixedly connected to the upper part of the vertical guide rod linear bearing 14 of the vertical guide mechanism through a hollow tube 12. The function of the hollow tube 12 is to support the load-bearing plate 13. When a mass block is placed on the load-bearing plate 13, the force exerted on the load-bearing plate 13 can be directly transmitted to the inclined rod 7, thereby driving the transverse guide rod 4 to move. Since the transverse guide rod 4 is constrained by the transverse guide rod linear bearing 3, it can only perform linear motion in the horizontal direction.

[0042] The vertical guide rod linear bearing 14 is symmetrically fixed with support connection blocks 9 on both sides, and the support connection blocks 9 are fixedly connected to the diagonal rod hinge support 8. The diagonal rod hinge support 8 is fixedly connected to the support connection blocks 9 by bolts. Bolts are used to pass through the load plate 13, the hollow tube 12, the vertical guide rod linear bearing 14, and the support connection blocks 9 in sequence for fixed connection. Bolts are used to pass through the through holes in the load plate 13, the through holes in the hollow tube 12, the through holes in the vertical guide rod linear bearing 14, and the bolt holes in the support connection blocks 9 to achieve fixed connection. The diagonal rod hinge support 8 is hinged to the diagonal rod 7. Figure 2 As shown, the shape of the inclined rod hinge support 8 is π-shaped, and two pairs of fixing holes I are provided on the inclined rod hinge support 8. Figure 3 As shown, the support connection block 9 is rectangular in shape, and a circular through hole is provided in the middle of the support connection block 9, which is sleeved on the vertical guide rod linear bearing 14, and bolt holes are provided on both sides of the circular through hole, through which the support connection block 9 is fixedly connected to the vertical guide rod linear bearing 14. Two pairs of fixing holes are provided on both sides of the bolt hole, and the two pairs of fixing holes are respectively fixedly connected to the fixing holes 1 on the inclined rod hinge support 8 on both sides by bolts. The other pair of fixing holes on the inclined rod hinge support 8 is hinged to one end of the inclined rod 7 through a pin shaft.

[0043] As a further implementation, the horizontal guide mechanism includes a transverse guide rod 4, one end of which is movably arranged on the transverse guide rod linear bearing 3, and the transverse guide rod 4 moves horizontally left and right under the action of the transverse guide rod linear bearing 3. The transverse guide rod linear bearing 3 is detachably connected to the bracket 2, so that the height of the transverse guide rod linear bearing 3 relative to the bracket 2 can be adjusted. The other end of the transverse guide rod 4 is hinged to the inclined rod 7, and the other ends of the two transverse guide rods 4 are respectively fixedly connected to the two ends of the horizontal tension spring 15. When a mass block is placed on the load plate 13, the force exerted on the load plate 13 can be directly transmitted to the inclined rod 7, thereby driving the transverse guide rod 4 to move. Since the transverse guide rod 4 is constrained by the transverse guide rod linear bearing 3, it can only perform linear motion in the horizontal direction.

[0044] like Figure 4 and Figure 5As shown, a radial bearing 5 is fixed to the other end of the transverse guide rod 4, and a U-shaped groove is provided at the other end of the transverse guide rod 4. The width of the U-shaped groove is greater than the diameter of the inclined rod 7. Through holes are provided at both ends of the U-shaped groove. The radial bearing 5 is sleeved on the other end of the transverse guide rod 4. The inner diameter of the radial bearing 5 is the same diameter as the small hole on the transverse guide rod 4. The outer diameter of the radial bearing 5 forms a transition fit with the circular hole of the inclined rod 7. The pin 6 passes through this diameter, so that the inclined rod 7 and the transverse guide rod 4 are hinged together. The radial bearing 5 is hinged to the inclined rod 7 through the pin 6. The pin 6 passes through the radial bearing 5, the transverse guide rod 4, the inclined rod 7, the transverse guide rod 4 and the radial bearing 5 in sequence, and the pin 6 extends out of both sides of the radial bearing 5. The ends of the horizontal tension spring 15 are fixed on both sides of the pin 6, and the two horizontal tension springs 15 are symmetrically arranged about the inclined rod 7. The two ends of the inclined rod 7 are provided with connecting holes, which are respectively hinged to the fixing hole I and the pin 6 of the inclined rod hinge support 8. The two ends of a pair of inclined rods 7 form a hinge through a radial bearing 5 and a pin 6 (short pin), the inner end (close to the center) of the inclined rod 7 is connected to the inclined rod hinge support 8, and the outer end (far away from the center) of the inclined rod 7 is hinged to the inner end (close to the center) of the transverse guide rod 4 through a radial bearing 5 and a pin 6 (long pin), and the pin 6 (long pin) is symmetrically used to hang the horizontal tension spring 15, such as Figure 7 As shown in (b), both ends of the horizontal tension spring 15 are hung on the pin 6, and the horizontal tension spring 15 and the diagonal rod 7 provide negative stiffness.

[0045] like Figure 6 As shown, the bracket 2 is provided with a long central through hole and a side hole, the central through hole matches the transverse guide rod linear bearing 3 of the horizontal guide mechanism, the transverse guide rod linear bearing 3 is slidably arranged in the central through hole, and the transverse guide rod linear bearing 3 is connected to the side hole through a positioning bolt, and the height of the transverse guide rod linear bearing 3 can be adjusted by adjusting the positioning bolt. The lower part of the bracket 2 is fixed on the fixed plate 1. The movement of the linear bearing 3 is limited by the positioning bolt, and when the positioning bolt is loosened, the linear bearing 3 can be adjusted up and down.

[0046] As a further implementation method, a debugging method of a constant quasi-zero stiffness vibration isolation structure based on a horizontal tension spring, the steps of which are as follows:

[0047] (1) Figure 7 As shown, a force diagram of the constant quasi-zero stiffness vibration isolation structure in the initial state is drawn. Since the two identical horizontally symmetrical tension springs can be equivalent to one spring, its stiffness is twice that of a single tension spring. In order to facilitate plane mechanics analysis, the two tension springs are equivalent to tension springs with a stiffness of k1. According to the force conditions of the system, the applied force, the tension spring, and the vertical spring are combined in the vertical direction to obtain the applied force:

[0048]

[0049] Wherein, k1 is the stiffness of two horizontal tension springs 15 equivalent to one tension spring, k2 represents the stiffness of the vertical spring 11, x is the displacement from the initial position, y is the displacement from the static equilibrium position, and x=y+h; a is the horizontal component of the diagonal rod 7 in the initial state; δ represents the pre-tension of the horizontal tension spring 15 in the initial state; h is the distance from the intersection of the diagonal rods to the static equilibrium position in the initial state, and f h is the inward elastic force generated by the pre-tensioning of the horizontal tension spring, f h The component force in the vertical direction is part of f. The diagonal rod and the horizontal tension spring produce negative stiffness, which is combined with the positive stiffness of the vertical spring to form a mechanical characteristic of quasi-zero dynamic stiffness, which can be constructed as a quasi-zero stiffness vibration isolator. The static equilibrium position is the position of the hinge point of the two diagonal rods when the diagonal rod 7 is in a horizontal state. That is, the static equilibrium position is the state when the diagonal rod is in a horizontal state.

[0050] (2) By establishing the force-displacement formula, the relationship between the force and displacement in the system is determined. In order to better analyze the influence of various parameter characteristics on the system and on each other, the applied force f and its expression are dimensionless and divided by The dimensionless applied force can be obtained

[0051]

[0052] in, The stiffness ratio of the horizontal extension spring to the vertical spring Intermediate variables and

[0053] (3) Using dimensionless applied forces For dimensionless displacement The first-order derivative can be used to obtain the dimensionless stiffness of the system.

[0054]

[0055] (4) In the static equilibrium position, the dimensionless stiffness By taking the first-order and second-order derivatives respectively, we can obtain the parameter conditions of zero stiffness characteristic α=0.25 and

[0056] (5) The ratio α of the stiffness of the horizontal tension spring 15 to the stiffness of the vertical spring 11 satisfies 0<α<0.25, and in the initial state, the pre-stretching length δ of the horizontal tension spring 15 is adjusted to be twice the horizontal component a of the lower pair of diagonal bars of the diagonal bar 7 in the initial state, that is, δ=2a. The constant quasi-zero stiffness vibration isolation structure has a constant quasi-zero stiffness characteristic and has a good ultra-low frequency vibration isolation effect.

[0057] Starting displacement from the static equilibrium position, the quasi-zero stiffness characteristic near the static equilibrium point, the stiffness is a constant quasi-zero stiffness state. On the basis of the traditional linear vibration isolation system, by introducing a structure that can provide negative stiffness, the dynamic stiffness of the vibration isolator is effectively reduced without reducing the bearing capacity of the vibration isolator. The constant quasi-zero stiffness can be adjusted as needed.

[0058] Figure 8 for and the stiffness displacement curve and force displacement curve with α = 0.24, where (a) is different Stiffness displacement curve under different conditions, (b) Force displacement curve under certain conditions. Figure 8 The constant quasi-zero stiffness characteristic is shown. When 0<α<0.25, we can obtain Figure 8 The constant quasi-zero stiffness characteristic is shown.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A debugging method for a constant-value quasi-zero stiffness vibration isolation structure based on a horizontal tension spring, the vibration isolation structure comprising a vertical spring (11), the vertical spring (11) being arranged on a vertical spring guide rod (10), characterized in that: A vertical guide mechanism is movably provided on the vertical spring guide rod (10), a vertical spring (11) is arranged below the vertical guide mechanism, and a load-bearing mechanism is provided on the vertical guide mechanism; negative stiffness structures are symmetrically provided on both sides of the vertical guide mechanism, the negative stiffness structures include an inclined rod (7) and a horizontal tension spring (15), one end of the inclined rod (7) is hinged to the vertical guide mechanism, and the other end of the inclined rod (7) is hinged to the horizontal guide mechanism, the horizontal guide mechanism is movably connected to the bracket (2), and the two horizontal guide mechanisms are connected via the horizontal tension spring (15); The vertical guide mechanism comprises a vertical guide rod linear bearing (14), the upper part of the vertical spring guide rod (10) is movably arranged in the vertical guide rod linear bearing (14), the upper part of the vertical spring (11) is fixedly connected to the lower part of the vertical guide rod linear bearing (14); the upper part of the vertical guide rod linear bearing (14) is fixed with a load-bearing mechanism; The horizontal guide mechanism comprises a transverse guide rod (4), one end of which is movably arranged on a transverse guide rod linear bearing (3), and the transverse guide rod linear bearing (3) is detachably connected to the bracket (2); the other end of the transverse guide rod (4) is hinged to the oblique rod (7), and the other ends of the two transverse guide rods (4) are respectively fixedly connected to the two ends of the horizontal tension spring (15); A radial bearing (5) is fixed to the other end of the transverse guide rod (4), the radial bearing (5) is hinged to the diagonal rod (7) through a pin (6), and the end of the horizontal tension spring (15) is fixed to the pin (6); The load-bearing mechanism comprises a load-bearing plate (13), and the load-bearing plate (13) is fixedly connected to the upper part of the vertical guide rod linear bearing (14) of the vertical guide mechanism through a hollow tube (12); Support connection blocks (9) are symmetrically fixed on both sides of the vertical guide rod linear bearing (14), the support connection blocks (9) are fixedly connected to the inclined rod hinge support (8), and the inclined rod hinge support (8) is hinged to the inclined rod (7); The number of the horizontal tension springs (15) is two and they are respectively arranged on both sides of the vertical spring guide rod (10); The static equilibrium position is the position of the hinge point of the two inclined rods when the inclined rod (7) is in a horizontal state. The steps of the debugging method are as follows: (1) Draw a force diagram of the constant quasi-zero stiffness vibration isolation structure in the initial state to obtain the applied force: Wherein, k1 is the stiffness of two horizontal tension springs (15) equivalent to one tension spring, k2 represents the stiffness of the vertical spring (11), x is the displacement from the initial position, y is the displacement from the static equilibrium position; a is the horizontal component of the diagonal rod (7) in the initial state; δ represents the pre-tension of the horizontal tension spring (15) in the initial state; h is the distance from the intersection of the diagonal rods to the static equilibrium position in the initial state; (2) The applied force f and its expression are dimensionless. in, The stiffness ratio of the horizontal extension spring to the vertical spring Intermediate variables And x=y+h; (3) Using dimensionless applied forces For dimensionless displacement The first-order derivative can be used to obtain the dimensionless stiffness of the system. (4) In the static equilibrium position, the dimensionless stiffness Find the second derivative and make it equal to zero and let is equal to zero, we can get the parameter conditions of zero stiffness characteristic α=0.25 and (5) The ratio α of the stiffness of the horizontal tension spring (15) to the stiffness of the vertical spring (11) satisfies 0<α<0.25, and in the initial state, the pre-stretching length δ of the horizontal tension spring (15) is adjusted to be twice the horizontal component a of the lower pair of diagonal bars of the diagonal bar (7) in the initial state, that is, δ=2a, and then adjusted to a constant value quasi-zero stiffness vibration isolation structure.

2. The debugging method of the constant quasi-zero stiffness vibration isolation structure based on the horizontal tension spring according to claim 1 is characterized in that: The bracket (2) is fixed on the fixed plate (1); a vertical spring guide rod support (16) is provided at the center of the two brackets (2) on the fixed plate (1); a vertical spring guide rod (10) is fixedly provided on the vertical spring guide rod support (16); the lower part of the vertical spring (11) is fixedly connected to the vertical spring guide rod support (16); the bracket (2) is provided with a long central through hole and a side hole; the central through hole matches the transverse guide rod linear bearing (3) of the horizontal guide mechanism; the transverse guide rod linear bearing (3) is connected to the side hole through a positioning bolt.

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