Lightweight high-rigidity sandwich superstructure plate with ultralow-frequency band gap and assembly method of lightweight high-rigidity sandwich superstructure plate

Abstract

The invention discloses a lightweight high-rigidity sandwich superstructure plate with an ultralow frequency band gap and an assembly method, the structure plate comprises a plurality of frame units arranged in a rectangular array, each frame unit comprises a support frame, substrates and a quasi-zero rigidity-inertia amplification coupling resonance unit, and the support frame is connected between the two substrates; the quasi-zero stiffness-inertia amplification coupling resonance unit is arranged on the supporting frame and comprises a lever, a quasi-zero stiffness vibrator and a mass block, and the lever is hinged to the supporting frame; the quasi-zero stiffness vibrator is located below one end of the lever and comprises a supporting piece, two positive stiffness elements, two negative stiffness elements and a connecting plate, and the supporting piece is connected to the substrate; the two positive stiffness elements are vertically and symmetrically arranged at the two ends of the supporting plate; the two negative stiffness elements are respectively connected to the inner sides of one ends of the two positive stiffness elements; the mass block is connected to the other end of the lever, the connecting plate is connected between the two negative stiffness elements, and active control over bending wave vibration in the ultralow frequency range in engineering can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical vibration, in particular to a lightweight and high-rigidity sandwich superstructure plate with an ultra-low frequency band gap and an assembly method thereof. Background Art

[0002] In the manufacturing, operation and maintenance of equipment, the level of vibration control has become an important influencing factor and evaluation index. Especially as the equipment develops towards high speed, light weight, large size, heavy load and extreme environment operation, the vibration problem in the operation of equipment has become increasingly prominent. Strong vibration seriously reduces the performance of equipment, has an important impact on the safe operation of instruments and equipment, and can directly lead to serious accidents such as loss of control, load failure, structural fatigue fracture, explosion, disintegration, etc. Vibration control is an urgent problem to be solved in the manufacturing and application of high-end equipment. In recent years, it has been widely studied in basic disciplines and engineering applications. Among them, ultra-low frequency vibration has a longer propagation distance due to its long wavelength, slower energy attenuation, stronger penetration ability, smaller attenuation caused by damping, and the ultra-low frequency noise generated has greater harm to human life and production, so it usually receives more attention.

[0003] Plate structures are widely used basic support and protection units in engineering. They are widely present in the cabin structures of vehicles such as automobiles, ships, trains, and aircraft. They are also important support and protection components for large machine tools such as high-speed precision machine tools. While bearing a variety of loads, they are not only the main generator and transmission carrier of vibration, but also the main transmission path and direct radiation source of noise. Therefore, plate structures have always been the focus of research in the field of engineering structure vibration control, requiring them to have high support stiffness and good vibration and noise reduction performance. Existing studies have shown that sandwich structures based on honeycomb, corrugation, etc., as a periodic composite structure, have natural structural characteristics such as light weight and high stiffness, but do not have new vibration band gap characteristics.

[0004] In actual engineering, plate structures are mainly used for support and protection. They need to bear multiple loads during operation and generate and transmit vibrations at the same time. Therefore, plate structures usually adopt high stiffness and large thickness designs. However, for widely used lightweight, high stiffness and thick plate structures, neither the traditional vibration reduction method nor the latest superstructure-based design scheme can effectively solve the problem of ultra-low frequency vibration control in the range of 0-10Hz. Summary of the invention

[0005] The purpose of the present invention is to provide a lightweight and high-rigidity sandwich superstructure plate with an ultra-low frequency band gap and an assembly method, which can effectively solve the problem of ultra-low frequency vibration control of the plate structure in the range of 0-10 Hz.

[0006] The technical solution of the present invention is:

[0007] A lightweight and high-rigidity sandwich superstructure plate with an ultra-low frequency band gap comprises a plurality of frame units, the plurality of frame units are arranged in a rectangular array, and adjacent frame units are tightly connected, each of the frame units comprises: a support frame and two substrates, the two substrates are symmetrically arranged in upper and lower positions; the support frame is a columnar support connected between the two substrates, located at a position where the two substrates are offset from the center, and further comprises: a quasi-zero stiffness-inertia amplified coupling resonance unit, the quasi-zero stiffness-inertia amplified coupling resonance unit is arranged on the support frame, and comprises: a lever, a plate structure, the lever is hinged to the support frame so that both ends of the lever can move up and down with the hinge with the support frame as the center; A zero-stiffness vibrator is fixed on the surface of the substrate below and is located below one end of the lever. The quasi-zero-stiffness vibrator includes: a support member, a plate structure, horizontally connected to the surface of the substrate below; two positive stiffness elements, symmetrically arranged at both ends of the support plate, and the positive stiffness elements are vertically arranged to the substrate; two negative stiffness elements are respectively connected to the inner sides of one end of the two positive stiffness elements, the two negative stiffness elements are symmetrically arranged and inclined toward the middle position of the two positive stiffness elements; a connecting plate, connected between the two negative stiffness elements, the connecting plate and the lever are adhesively connected to transfer the load; a mass block, connected to the other end of the lever. When one end of the lever attached to the connecting plate produces a vertical downward displacement to compress the vibrator, the negative stiffness element buckles and deforms as the compression continues to increase, thereby generating a negative stiffness physical property, that is, the force decreases with the increase of displacement; when one end of the lever attached to the connecting plate produces a vertical downward displacement to compress the vibrator, the positive stiffness element also deforms along the outer side of the positive stiffness element as the compression continues to increase, but this deformation belongs to the deformation of the positive stiffness property, that is, the force increases with the increase of displacement, and thus the negative stiffness property generated by the buckling deformation of the negative stiffness element is combined with the positive stiffness property generated by the deformation of the positive stiffness element to achieve a quasi-zero stiffness property; due to the existence of the lever in the sandwich superstructure plate, when subjected to external excitation, the lever produces a vertical displacement at both ends with the hinge as the center, amplifying the mass while compressing the vibrator to achieve a quasi-zero stiffness property, thereby achieving ultra-low frequency vibration reduction, and this process is completed in one go, thereby avoiding the defect of the traditional quasi-zero stiffness that a pre-displacement needs to be applied when achieving low-frequency vibration reduction, and further reducing the band gap range on the basis of the original low-frequency band gap to obtain an ultra-low frequency band gap.

[0008] Furthermore, a reserved hole is provided on the support frame, a through hole is provided on the lever, and the lever and the support frame are connected via a hinge provided between the through hole and the reserved hole.

[0009] Furthermore, the two positive stiffness elements, the two negative stiffness elements and the connecting plate are all rubber plates. The rubber material is relatively soft, has low stiffness, is easy to achieve a low-frequency band gap, has good buffering performance, and is easy to absorb energy. The support plate and the substrate are made of aluminum, and the mass block is made of steel.

[0010] Furthermore, the support plate, the two positive stiffness elements, the two negative stiffness elements and the connection plate in the quasi-zero stiffness vibrator are connected by bonding.

[0011] Furthermore, the mass block is a rectangular block.

[0012] Furthermore, adjacent frame units are connected via a substrate, and the substrates of adjacent frame units are connected via bonding.

[0013] Furthermore, the lever is connected at a middle position of the mass block.

[0014] Furthermore, a method for assembling a lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap comprises the following steps:

[0015] Assemble the frame unit, arrange the substrate on the upper and lower surfaces of the support frame respectively, and its composition technology mainly adopts welding / pasting or casting into an integrated structure, so that the frame unit structure composed of the substrate and the support frame has the characteristics of light weight and high rigidity;

[0016] The assembled multiple frame units are periodically arranged along the x and y directions to form a periodic frame plate structure; and the frame units are welded / pasted or cast during the periodic arrangement process to form a periodic frame plate structure; the frame plate structure has the characteristics of light weight, high rigidity, and thick size (thick plate), that is, it has a strong supporting and protective function, but has no vibration band gap characteristics, that is, it cannot perform vibration reduction;

[0017] The quasi-zero stiffness-inertia amplified coupling resonance unit is assembled into the frame unit to form a sandwich superstructure plate unit; in the unit, the quasi-zero stiffness vibrator of the quasi-zero stiffness-inertia amplified coupling resonance unit and the base plate are seamlessly assembled by bonding, and the support frame and the lever are hinged at the opening position so that both ends of the lever can move up and down with the opening position as the center;

[0018] The sandwich superstructure plate units are arranged periodically along the x and y directions to form a sandwich superstructure plate, which is used for actual engineering vibration reduction. The sandwich superstructure plate is a lightweight, high-rigidity, thick-size vibration-reducing superstructure plate with ultra-low frequency vibration band gap characteristics. The sandwich superstructure plate units are welded / pasted or cast during the periodic arrangement process to form a new frame plate structure. The sandwich superstructure plate structure has the characteristics of light weight, high rigidity, and thick size (thick plate), that is, it has a strong supporting and protective function, and at the same time has ultra-low frequency vibration band gap characteristics, which can be used for actual engineering vibration reduction.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention aims at the problem that it is difficult to realize vibration control in the ultra-low frequency (0-10Hz) range for a lightweight and high-rigidity sandwich superstructure plate. The quasi-zero stiffness principle and the inertia amplification principle are introduced into the design of the lightweight and high-rigidity sandwich superstructure plate, and a resonance unit of quasi-zero stiffness and inertia amplification coupling with the characteristics of "high static and low dynamic stiffness" and "small mass to achieve large inertia" is proposed, so as to construct a sandwich superstructure plate with lightweight and high-rigidity ultra-low frequency vibration reduction characteristics. The plate has practical characteristics such as light weight, high stiffness, large plate thickness, simple structure, etc., and has ultra-low frequency (0-10Hz) vibration band gap characteristics. In the band gap frequency range, its bending wave vibration can be significantly suppressed. In addition, there is a lever in the sandwich superstructure plate that represents the inertia amplification principle. When subjected to external excitation, the lever amplifies the mass and compresses the vibrator to realize the quasi-zero stiffness characteristic, thereby realizing ultra-low frequency vibration reduction. This process is completed in one go, thereby avoiding the defect that the traditional quasi-zero stiffness needs to apply pre-displacement when realizing low-frequency vibration reduction. By actively designing the structural parameters of the plate, active control of ultra-low frequency bending wave vibrations in engineering projects can be achieved, thereby effectively solving the technical difficulties in ultra-low frequency (0-10Hz) vibration control of traditional lightweight and high-rigidity thick plate protection structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a stereogram of the structural schematic diagram of the present invention.

[0022] Figure 2 It is a schematic diagram of the frame unit structure of the present invention.

[0023] Figure 3 It is a schematic diagram of the quasi-zero stiffness vibrator structure of the present invention.

[0024] Figure 4 It is a schematic diagram of the quasi-zero stiffness-inertia amplification coupling principle of the present invention.

[0025] Figure 5 This is the energy band structure diagram of the present invention.

[0026] Figure 6 This is the transmission characteristic diagram of the present invention (0-50Hz).

[0027] Figure 7 This is the transmission characteristic diagram of the present invention (0-15Hz).

[0028] Figure 8 This is a schematic diagram of the inertia amplification structure based on the lever principle.

[0029] Fig. 9 Schematic diagram of the static equilibrium position of the quasi-zero stiffness resonator.

[0030] Fig.10 Schematic diagram of static analysis of quasi-zero stiffness resonator.

[0031] Fig.11 It is a schematic diagram of the out-of-plane excitation transmission process within the band gap range of the present invention.

[0032] Among them, 1. frame unit, 2. support frame, 3. substrate, 4. quasi-zero stiffness-inertial amplified coupling resonance unit, 5. lever, 6. quasi-zero stiffness oscillator, 61. support, 62. positive stiffness element, 63. negative stiffness element, 64. connecting plate, 7. mass block. DETAILED DESCRIPTION

[0033] Combine the following Figures 1 to 11 , the specific embodiments of the present invention are described in detail. In the description of the present invention, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0034] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0035] Example

[0036] like Figure 1 As shown, a lightweight and high-rigidity sandwich superstructure plate with an ultra-low frequency band gap comprises: a plurality of frame units 1, and the plurality of frame units 1 are arranged in a rectangular array, and adjacent frame units 1 are tightly connected, such as Figure 2 As shown, each frame unit 1 includes: a support frame 2, two substrates 3 and a quasi-zero stiffness-inertia amplified coupling resonance unit 4, the two substrates 3 are symmetrically arranged in the upper and lower positions; the support frame 2 is a columnar bracket connected between the two substrates 3, and is located at a position where the two substrates 3 are off-center; the quasi-zero stiffness-inertia amplified coupling resonance unit 4 is arranged on the support frame 2, as shown in FIG. Figure 2As shown, the quasi-zero stiffness-inertia amplified coupling resonance unit 4 includes: a lever 5, a quasi-zero stiffness vibrator 6 and a mass block 7. The lever 5 is a plate structure. The lever 5 is hinged to the support frame 2 so that both ends of the lever 5 can move up and down with the hinge with the support frame 2 as the center; the quasi-zero stiffness vibrator 6 is fixed on the plate surface of the substrate 3 located below, and is located below one end of the lever 5, as shown in FIG. Figure 3 As shown, the quasi-zero stiffness vibrator 6 includes: a support member 61, two positive stiffness elements 62, two negative stiffness elements 63 and a connecting plate 64. The support member 61 is a plate structure, horizontally connected to the surface of the substrate 3 located below; the two positive stiffness elements 62 are symmetrically arranged at both ends of the support plate, and the positive stiffness elements 62 are arranged vertically to the substrate 3; the two negative stiffness elements 63 are respectively connected to the inner sides of one end of the two positive stiffness elements 62, and the two negative stiffness elements 63 are symmetrically arranged and inclined to the middle position of the two positive stiffness elements 62; the connecting plate 64 is connected between the two negative stiffness elements 63, and the connecting plate 64 is glued to the lever 5 for transferring the load; the mass block 7 is a rectangular block, connected to the other end of the lever 5; when the end of the lever 5 to which the connecting plate 64 is glued produces a vertical downward displacement to compress the vibrator, the negative stiffness element 63 undergoes buckling deformation as the compression continues to increase, thereby generating a negative stiffness physical property, That is, the force decreases with the increase of displacement; when one end of the lever 5 attached to the connecting plate 64 produces a vertical downward displacement to compress the vibrator, the positive stiffness element 62 also deforms along the outer side of the positive stiffness element 62 as the compression continues to increase, but the deformation belongs to the deformation of the positive stiffness characteristic, that is, the force increases with the increase of displacement, and the negative stiffness characteristic generated by the buckling deformation of the negative stiffness element 63 is combined with the positive stiffness characteristic generated by the deformation of the positive stiffness element 62 to achieve a quasi-zero stiffness characteristic; due to the presence of the lever 5 in the sandwich superstructure plate, when subjected to external excitation, the lever 5 produces a vertical displacement at both ends with the hinge as the center, amplifying the mass while compressing the vibrator to achieve a quasi-zero stiffness characteristic, thereby achieving ultra-low frequency vibration reduction. This process is completed in one go, thereby avoiding the defect of traditional quasi-zero stiffness that requires pre-displacement when achieving low-frequency vibration reduction, and further reducing the band gap range on the basis of the original low-frequency band gap to obtain an ultra-low frequency band gap.

[0037] like Figure 2 As shown, a reserved hole is provided on the support frame 2, a through hole is provided on the lever 5, and the lever 5 is connected to the support frame 2 via a hinge arranged between the through hole and the reserved hole. When subjected to external excitation, the lever 5 generates vertical displacement at both ends with the hinge as the center, thereby amplifying the mass while compressing the vibrator to achieve a quasi-zero stiffness characteristic, thereby realizing ultra-low frequency vibration reduction.

[0038] In some embodiments, the two positive stiffness elements 62, the two negative stiffness elements 63 and the connecting plate 64 are all rubber plates, the support plate and the base plate 3 are made of aluminum, and the mass block 7 is made of steel. The stiffness element 62, the negative stiffness element 63 and the connecting plate 64 made of rubber material are softer, have low stiffness, are easy to achieve low-frequency band gap, have good buffering performance, and are easy to absorb energy.

[0039] In some embodiments, in order to facilitate processing and manufacturing, the support plate, two positive stiffness elements 62, two negative stiffness elements 63 and the connecting plate 64 in the quasi-zero stiffness vibrator 6 are connected by bonding. In actual processing, in order to further reduce the error of the experiment, the support plate, two positive stiffness elements 62, two negative stiffness elements 63 and the connecting plate 64 in the quasi-zero stiffness vibrator 6 can also be prepared by an integrated molding technology, so that the support plate, two positive stiffness elements 62, two negative stiffness elements 63 and the connecting plate 64 in the quasi-zero stiffness vibrator 6 form a whole, thereby reducing the experimental error.

[0040] In some embodiments, adjacent frame units 1 are connected via substrates 3 , and substrates 3 of adjacent frame units 1 are connected via bonding.

[0041] In some embodiments, the lever 5 is connected to the middle position of the mass block 7 to make the masses of the left and right parts of the mass block 7 connected by the lever 5 uniform, so as to prevent the torque generated on the lever due to the uneven mass of the left and right parts of the mass block 7, thereby affecting the actual effect.

[0042] The assembly method of a lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap in this embodiment includes the following steps:

[0043] Assemble the frame unit 1, and arrange the substrate 3 on the upper and lower surfaces of the support frame 2 respectively. The composition technology mainly adopts welding / pasting or casting into an integrated structure, so that the frame unit 1 structure composed of the substrate 3 and the support frame 2 has the characteristics of light weight and high rigidity;

[0044] The assembled multiple frame units 1 are periodically arranged along the x and y directions to form a periodic frame plate structure; and the frame units 1 are welded / pasted or cast during the periodic arrangement process to form a periodic frame plate structure; the frame plate structure has the characteristics of light weight, high rigidity, and thick plate, that is, it has a strong supporting and protective function, but has no vibration band gap characteristics, that is, it cannot perform vibration reduction;

[0045] The quasi-zero stiffness-inertia amplified coupling resonance unit is assembled into the frame unit 1 to form a sandwich superstructure plate unit; in the unit, the quasi-zero stiffness vibrator 6 of the quasi-zero stiffness-inertia amplified coupling resonance unit is seamlessly assembled with the substrate 3 by bonding, and the support frame 2 and the lever 5 are hinged at the opening position so that both ends of the lever 5 can move up and down with the opening position as the center;

[0046] The sandwich superstructure plate units are arranged periodically along the x and y directions to form a sandwich superstructure plate, which is used for actual engineering vibration reduction. The sandwich superstructure plate is a lightweight, high-rigidity, thick-size vibration-reducing superstructure plate with ultra-low frequency vibration band gap characteristics. The sandwich superstructure plate units are welded / pasted or cast during the periodic arrangement process to form a new frame plate structure. The sandwich superstructure plate structure has the characteristics of light weight, high rigidity, and thick size thick plate, that is, it has a strong support and protection function, and at the same time has the characteristics of ultra-low frequency vibration band gap, which can be used for actual engineering vibration reduction.

[0047] like Figure 8 As shown in the figure, the lever structure can adjust the inertia amplification effect by the arm length ratio. Figure 8 In the diagram, the lever structure has only one free end. According to the force analysis and Newton's second law, the relationship between the various parts of the end point is as follows:

[0048] F l l1=mü r l2,u l l2=u r l1

[0049] Let R = l2 / l1, then

[0050] F l =R 2 mü l

[0051] From the above derivation, it can be seen that Figure 8 The coefficient between the endpoint force and acceleration of the two mechanisms can be greater than the true mass of the structure, which has the effect of inertia amplification.

[0052] Figure 4 The free vibration differential equation of the lever structure is:

[0053] R 2 mü l +Ku l =0

[0054] Therefore, the natural frequency of the lever structure is:

[0055]

[0056] Among them, F l is the inertia force at the left end of the lever, u lis the displacement of the left end of the lever, u r is the displacement of the right end of the lever, l1 is the distance between the left end of the lever and the fulcrum, l2 is the distance between the right end of the lever and the fulcrum, K is the spring stiffness, ü r is the acceleration of the right end of the lever, ü l is the acceleration of the left end of the lever, R is the arm length ratio, m is the mass of the mass block 7, ω0 is the natural frequency of the lever structure. From the above derivation, it can be seen that the derived inertial mass and the real mass have the same properties in the moving system and can effectively reduce the natural frequency of the structure.

[0057] Fig. 9 and Fig.10 The principle of the quasi-zero stiffness resonator is shown. When the mass vibrates around the static equilibrium position, the two inclined springs provide negative stiffness in the vertical direction to offset the positive stiffness of the vertical spring. The mass can only vibrate in the vertical direction, and the inclined springs deform symmetrically relative to the vertical spring. As Fig.10 shown, the restoring force of the quasi-zero stiffness resonator can be obtained through static analysis.

[0058]

[0059] In the above formula, f is the restoring force; y is the displacement of the mass deviating from the static equilibrium position, as Fig.10 shown; k v and k o are the stiffnesses of the vertical spring and the inclined spring respectively; l is the original length of the inclined spring; a is the deformation length of the inclined spring at the static equilibrium position, and a < l. Using The dimensionless restoring force is:

[0060]

[0061] where α = k o / k v represents the ratio of the stiffness of the inclined spring to the stiffness of the vertical spring; is the dimensionless restoring force; is the dimensionless displacement of the mass deviating from the static equilibrium position; as above, the stiffness of the vertical spring can be partially or completely offset by the negative stiffness mechanism. Let η (0 ≤ η ≤ 1) be the proportion of the remaining stiffness of the resonator at the vertical static equilibrium position after being offset by the negative stiffness mechanism, then the restoring force can be rewritten as:

[0062]

[0063] By taking the derivative of the above expression for the dimensionless displacement , the dimensionless stiffness of the quasi-zero stiffness resonator is obtained as:

[0064]

[0065] To reduce the stiffness of the resonator, and thus the band gap, the stiffness can be offset by letting a ratio be 1-η. The formula is:

[0066]

[0067] In static equilibrium At , the dimensionless stiffness of the resonator is reduced from 1 to η. At this point, the parameters η, α and The only relationship that exists is:

[0068]

[0069] Equation (6) provides the relationship between the parameter k v , k o , a and l are related physical expressions. Substituting equation (6) into equation (3) and equation (4), and offsetting part of the stiffness of the quasi-zero stiffness resonator in the ratio of 1-η, the restoring force and stiffness of the quasi-zero stiffness resonator are obtained as shown below. It is worth noting that only in the static equilibrium position When the stiffness is is η, and as the displacement increases with the increase of .

[0070]

[0071] like Figure 4 As shown, a light-weight and high-rigidity sandwich superstructure plate with an ultra-low frequency band gap in this embodiment is combined with Fig. 9 and Fig.10 The quasi-zero stiffness principle shown and Figure 8 The inertia amplification principle shown in the figure not only has the characteristics of light weight, high stiffness, and thick size (thick plate), but can also be used for supporting and protecting actual engineering structures. At the same time, the quasi-zero stiffness principle and the inertia amplification principle are combined to introduce a quasi-zero stiffness-inertia amplification coupling resonance unit. Through the periodic arrangement of the combined assembly, the plate structure of this embodiment not only has the characteristics of light weight, high stiffness, and thick size, but also can be used for supporting and protecting actual engineering structures. Fig.11 Schematic diagram of the out-of-plane excitation transmission process within the bandgap range shown. Figure 4 A and B are schematic diagrams of the structure corresponding to the open and closed positions of the band gap, respectively. Figure 5 The A and B shown represent Figure 4 The mode vibration shapes corresponding to the opening and closing positions of the band gap. Figure 5 , Figure 6 and Figure 7As shown, the semi-structure of this embodiment has the ultra-low frequency (0-10Hz) vibration band gap characteristics, that is, the plate structure can suppress the ultra-low frequency (0-10Hz) vibration in the project, and the 15-50Hz vibration outside the band gap range is also in a state of continuous attenuation. In addition, due to the presence of the lever in the sandwich superstructure plate, when subjected to external excitation, the lever produces vertical displacement at both ends with the hinge as the center, amplifying the mass while compressing the vibrator to achieve quasi-zero stiffness characteristics, thereby achieving ultra-low frequency vibration reduction, thereby avoiding the defect that the traditional quasi-zero stiffness needs to apply pre-displacement when achieving low-frequency vibration reduction.

[0072] The above disclosures are only several preferred specific embodiments of the present invention. However, the embodiments of the present invention are not limited thereto. Any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap, characterized in that: include: A plurality of frame units (1), wherein the plurality of frame units (1) are arranged in a rectangular array, and adjacent frame units (1) are tightly connected, and each of the frame units (1) comprises: a support frame (2) and two substrates (3), and the two substrates (3) are symmetrically arranged in upper and lower positions; A support frame (2) connected between the two substrates (3) and located at a position off-center of the two substrates (3); and A quasi-zero stiffness-inertia amplified coupling resonance unit, wherein the quasi-zero stiffness-inertia amplified coupling resonance unit is arranged on the support frame (2), and comprises: A lever (5) having a plate structure, wherein the lever (5) is hingedly connected to the support frame (2) so that both ends of the lever (5) can move up and down with the hinged connection with the support frame (2) as the center; A quasi-zero stiffness vibrator (6) is fixed on the surface of the substrate (3) located below and is located below one end of the lever (5). The quasi-zero stiffness vibrator (6) comprises: a support member (61), a plate structure, horizontally connected to the surface of the substrate (3) located below; two positive stiffness elements (62), symmetrically arranged at the two ends of the support plate, the positive stiffness elements (62) being arranged perpendicularly to the substrate (3); two negative stiffness elements (63), respectively connected to the inner sides of one end of the two positive stiffness elements (62), the two negative stiffness elements (63) being symmetrically arranged and inclined toward the middle position of the two positive stiffness elements (62); a connecting plate (64), connected between the two negative stiffness elements (63), the connecting plate (64) being adhesively connected to the lever (5) for transmitting load; A mass block (7) is connected to the other end of the lever (5).

2. The lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap according to claim 1, characterized in that: The support frame (2) is provided with a reserved hole, the lever (5) is provided with a through hole, and the lever (5) and the support frame (2) are connected via a hinge arranged between the through hole and the reserved hole.

3. The lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap according to claim 1, characterized in that: The two positive stiffness elements (62), the two negative stiffness elements (63) and the connecting plate (64) are all rubber plates, the support plate and the base plate (3) are made of aluminum, and the mass block (7) is made of steel.

4. The lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap according to claim 1, characterized in that: The support plate, two positive stiffness elements (62), two negative stiffness elements (63) and the connecting plate (64) in the quasi-zero stiffness vibrator (6) are connected by bonding.

5. The lightweight and high-rigidity sandwich superstructure panel with ultra-low frequency band gap according to claim 1, characterized in that: The mass block (7) is a rectangular block.

6. The lightweight and high-rigidity sandwich superstructure panel with ultra-low frequency band gap according to claim 1, characterized in that: Adjacent frame units (1) are connected via a substrate (3), and the substrates (3) of adjacent frame units (1) are connected to each other via bonding.

7. The lightweight and high-rigidity sandwich superstructure panel with ultra-low frequency band gap according to claim 1, characterized in that: The lever (5) is connected at a middle position of the mass block (7).

8. The method for assembling a lightweight and high-rigidity sandwich superstructure panel with an ultra-low frequency band gap according to claim 1, characterized in that: The following steps are involved: Assembling the frame unit (1), arranging the base plate (3) on the upper and lower surfaces of the support frame (2) respectively, so that the frame unit (1) structure composed of the base plate (3) and the support frame (2) has light weight and high rigidity characteristics; Arranging the assembled multiple frame units (1) periodically along the x and y directions to form a periodic frame plate structure; The quasi-zero stiffness-inertia amplified coupling resonance unit is assembled into a frame unit (1) to form a sandwich superstructure plate unit; in the unit, the quasi-zero stiffness vibrator (6) of the quasi-zero stiffness-inertia amplified coupling resonance unit and the base plate (3) are seamlessly assembled by bonding, and the support frame (2) and the lever (5) are hinged at the opening position so that both ends of the lever (5) can move up and down with the opening position as the center; The sandwich superstructure plate units are periodically arranged along the x and y directions to form a sandwich superstructure plate, which is used for actual engineering vibration reduction.

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