A nonlinear vibration isolator imitating secretary bird

Abstract

The present invention provides a secretary bird-like nonlinear vibration isolator, comprising a load-bearing platform, a limiting device, a secretary bird-like wing module, a secretary bird-like lower limb module, and a base. Four limiting devices are mounted on the four corners of the load-bearing platform and the base, respectively. The secretary bird-like wing modules are mounted on either side of the load-bearing platform, and the secretary bird-like lower limb module is mounted between the load-bearing platform and the base, with the modules being axially symmetrically distributed about the vertical centerline of the load-bearing platform. The present invention's secretary bird-like nonlinear vibration isolator features a simple manufacturing method, high reliability, and a large load-bearing capacity, making it suitable for isolating vibration interference generated by low-frequency, high-amplitude vibration sources.

Description

Technical Field

[0001] The invention relates to the technical field of vibration reduction and isolation, and in particular to a secretary bird-like nonlinear vibration isolator. Background Art

[0002] In recent years, various methods, including active, semi-active, and passive vibration isolation technologies, have been developed in engineering practice to address vibration suppression issues. Passive vibration isolation technology is widely used due to its ease of implementation and high reliability. However, traditional linear passive vibration isolators encounter problems with excessive static deformation and instability when isolating low-frequency external disturbances. Nonlinear vibration isolators can effectively solve this problem. The quasi-zero stiffness system of such isolators has high static and low dynamic stiffness characteristics. When reaching the static equilibrium position, the dynamic stiffness is zero or quasi-zero, resulting in a lower natural frequency and a greater load-bearing capacity.

[0003] Patent application number CN202110202430.1 discloses a biomimetic vibration isolation system that primarily uses air springs to convert mechanical energy into internal energy, while a damping unit dampens vibrations. However, the air spring damping unit has a complex structure and requires constant maintenance of air pressure to ensure proper operation.

[0004] Patent document CN106402229B discloses a scissor-type quasi-zero stiffness vibration isolator and its operating method. This device achieves quasi-zero stiffness and vibration isolation by stacking positive and negative stiffness modules. However, the negative stiffness module requires many connecting rods, making assembly difficult.

[0005] Patent document CN213808606U discloses a quasi-zero-stiffness vibration isolator with a positive-negative parallel mechanism. This mechanism achieves zero stiffness by vertically arranging a positive spring and horizontally arranging a negative spring to prevent bending and deformation. However, this device has a weak load-bearing capacity and is not suitable for heavy loads.

[0006] Patent publication number CN109737168A discloses a quasi-zero-stiffness vibration isolator. This device utilizes a cross-arm structure, a T-shaped slide, and a guide rail to ensure that the extension and contraction of a tension spring are aligned horizontally. The T-shaped slide rail moves on the guide rail to adjust the negative stiffness, ultimately achieving zero stiffness. However, this device requires numerous parts, resulting in a complex structure and high maintenance costs.

[0007] In nature, when a secretary bird hunts, it usually goes through the following process: 1. Open and flap its wings to quickly approach the prey. 2. One leg is used for support, and the other leg is lifted upward. During this period, the supporting leg is bent outward so that the whole body is pressed downward and appears to be in a state of accumulating force. 3. The raised leg quickly steps on the prey's head and flaps its wings to maintain body balance. 4. The above actions are repeated continuously until the prey dies. In the above process, it only takes 15 milliseconds for the secretary bird to kick each time. Despite the repeated high-speed and high-frequency stepping actions, the body of the secretary bird can still maintain a relatively stable state. Therefore, the present invention refers to the body structure of the secretary bird and proposes a nonlinear vibration isolator that imitates the secretary bird. Summary of the Invention

[0008] In response to the above-mentioned shortcomings and deficiencies in the prior art, the present invention aims to provide a secretary bird-like nonlinear vibration isolator that can be applied over a wide frequency range and has high static and low dynamic characteristics. The secretary bird-like nonlinear vibration isolator of the present invention has the advantages of simple manufacturing method, high reliability, and large load-bearing capacity.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] A secretary bird-like nonlinear vibration isolator comprises a load-bearing platform, a limiting device, a secretary bird-like wing module, a secretary bird-like lower limb module and a base. The limiting devices are provided in four pieces and are respectively mounted on the four corners of the load-bearing platform and the base. The secretary bird-like wing modules are mounted on both sides of the load-bearing platform, and the secretary bird-like lower limb module is mounted between the load-bearing platform and the base, and are axially symmetrically distributed about the vertical center line of the load-bearing platform.

[0011] The secretary vulture wing module is installed symmetrically on the left and right sides of the load-bearing platform. The first scheme includes a vertical connecting seat, a hinge, a rigid plate, a first viscoelastic damping layer, and a first tension spring; the width of the rigid plate is narrower than the load-bearing platform, and it is a uniform rectangular hollow slender plate; one end of the rigid plate is connected to the load-bearing platform through a hinge, and the first viscoelastic damping layer is bonded to the lower surface of the rigid plate. The two vertical connecting seats on the upper surface of the rigid plate are distributed at the two corners of the hinged end of the rigid plate, and the two vertical connecting seats on the upper surface of the load-bearing platform are distributed at the edge position of the load-bearing platform on the same horizontal line as the vertical connecting seats on the rigid plate. The vertical connecting seats on the lower surface of the rigid plate and the load-bearing platform are symmetrical with the upper surface; the first tension spring is installed on the vertical connecting seats corresponding to the load-bearing platform and the rigid plate.

[0012] The secretary bird wing module is installed symmetrically on the left and right sides of the load-bearing platform. The second scheme includes a horizontal connecting seat, a flexible plate and a second viscoelastic damping layer. The flexible plate is a uniform rectangular hollow slender plate, which is fixed on the load-bearing platform through a horizontal connecting seat. The second viscoelastic damping layer is bonded to the lower surface of the flexible plate.

[0013] The wings of a secretary bird are covered with feathers, which are subjected to forces to maintain body balance during flapping. The first viscoelastic damping layer and the second viscoelastic damping layer are made of a viscoelastic polymer material that imitates the feathers of a secretary bird.

[0014] The secretary bird lower limb module comprises a rhombus structure consisting of a short connecting rod, a long connecting rod, a middle connecting rod, and a second tension spring, a connecting base, and a pressure spring; one end of the two short connecting rods is connected to the center point of the lower surface of the load-bearing platform through a fixed support, the other end of the two short connecting rods is hinged to one end of the two long connecting rods, the other end of the two long connecting rods is hinged to one end of the two middle connecting rods, and the other end of the two middle connecting rods is hinged to the upper end of the connecting base; the bottom end of the connecting base is fixedly connected to the base; the middle and upper parts of the two long connecting rods are hinged together, the shorter of the two sections cut by the connecting point of the short connecting rod and the long connecting rod is equal in length, thereby forming a small rhombus structure on the upper part of the secretary bird lower limb module; the longer of the two sections cut by the connecting point of the middle connecting rod and the long connecting rod is equal in length, thereby forming a large rhombus structure on the lower part of the secretary bird lower limb module; a second tension spring is provided between the two horizontal connection points of the large rhombus structure, and a pressure spring is provided on the connecting base. The included angle α between the middle connecting rod and the horizontal plane is determined according to actual load conditions. Different included angles α require different pressures for the vibration isolators to achieve quasi-zero stiffness.

[0015] The length ratio among the short connecting rod, the long connecting rod and the middle connecting rod is selected as 1:3.5:2.5 according to the ratio among the femur, tibia and tarsometatarsus of the secretary bird's leg.

[0016] The structure of the connecting base is: a cylinder is sleeved on a column, the bottom of the cylinder is fixedly connected to a lower extension support platform, the lower extension support platform is fixedly connected to the base, the outer surface of the cylinder is provided with an outer extension support circular surface, and the pressure spring is provided between the outer extension support circular surface and the lower extension support platform.

[0017] The advantages of the first solution are that the materials required for the secretary bird wing module are readily available, the rigid plate is connected to the load-bearing platform via a hinge, allowing for better swinging, and the device is less susceptible to environmental interference, allowing it to operate in complex conditions. The advantages of the second solution are that the secretary bird wing module is more compact than the first solution, with the flexible plate abutting the load-bearing platform via a horizontal connector, allowing it to be considered a single unit.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) The double diamond structure of the secretary bird's legs adopted in the present invention effectively broadens the frequency range of vibration isolation.

[0020] 2) The vibration isolator of the present invention has high static stiffness and low dynamic stiffness, and can effectively isolate low-frequency vibrations.

[0021] 3) The flexible plate in the present invention is designed to imitate the wings of a secretary bird, providing inertial force during the swinging process, which is beneficial to reducing the vibration of the equipment.

[0022] 4) The viscoelastic damping layer in this invention is a polymer material, modeled after feathers from secretary bird wings. A key characteristic of polymer deformation properties is viscoelasticity. Polymer materials can absorb vibration energy, partially converting it into heat and dissipating it, thus providing a damping effect. This helps reduce vibrations in the load-bearing platform.

[0023] 5) The present invention has a simple structure, is easy to process and manufacture, has a large vibration isolation stroke, and has a high bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0025] Figure 1 This is a schematic structural diagram of the first embodiment of the vibration isolator described in the present invention.

[0026] Figure 2 This is a schematic structural diagram of the second embodiment of the vibration isolator described in the present invention.

[0027] Figure 3 It is a structural schematic diagram of the horizontal connecting seat described in the present invention.

[0028] Figure 4 Schematic diagram of the structure of the hinge of the present invention.

[0029] Figure 5 Schematic diagram of the structure of the rigid board and the flexible board in the present invention.

[0030] Figure 6 Schematic diagram of the structure of the connecting rod in the present invention.

[0031] Figure 7 It is a structural schematic diagram of the vertical connecting seat described in the present invention.

[0032] The figure shows:

[0033] 101- load-bearing platform, 102- limit device, 103- vertical connecting seat, 104- hinge, 105- rigid plate, 106- first viscoelastic damping layer, 107- first tension spring, 108- short connecting rod, 109- long connecting rod, 110- second tension spring, 111- middle connecting rod, 112- connecting base, 113- pressure spring, 114- base

[0034] 201-horizontal connecting seat, 202-flexible plate, 203-second viscoelastic damping layer

[0035] 601-cylinder, 602-extension support circular surface, 603-column, 604-downward support platform DETAILED DESCRIPTION

[0036] The present invention will be described in detail below with reference to specific examples. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form.

[0037] like Figure 1 , Figure 4 , Figure 5 , Figure 6 As shown, a secretary bird-like nonlinear vibration isolator comprises a load-bearing platform 101, a limiting device 102, a secretary bird-like wing module, a secretary bird-like lower limb module and a base 114; the limiting devices 102 are four and are respectively installed on the four corners of the load-bearing platform 101 and the base 114; the secretary bird-like wing modules are installed on both sides of the load-bearing platform 101, and the secretary bird-like lower limb modules are installed between the load-bearing platform 101 and the base 114, and are axially symmetrically distributed about the vertical center line of the load-bearing platform (101).

[0038] The secretary bird wing module is installed symmetrically on the left and right sides of the load-bearing platform 101, including a vertical connecting seat 103, a hinge 104, a rigid plate 105, a first viscoelastic damping layer 106, and a first tension spring 107; the rigid plate 105 is narrower than the load-bearing platform 101 and is a uniform rectangular hollow slender plate; one end of the rigid plate 105 is connected to the load-bearing platform 101 through the hinge 104, the first viscoelastic damping layer 106 is bonded to the lower surface of the rigid plate 105, and the rigid plate 105 is connected to the load-bearing platform 101 through the hinge 104. The two vertical connecting seats 103 on the upper surface are distributed on the two corners of the hinged end of the rigid plate 105, and the two vertical connecting seats 103 on the upper surface of the load-bearing platform 101 are distributed on the edge of the load-bearing platform 101 on the same horizontal line as the vertical connecting seats 103 on the rigid plate 105. The vertical connecting seats 103 on the lower surface of the rigid plate 105 and the load-bearing platform 101 are symmetrical with the upper surface; a first tension spring 107 is installed on the vertical connecting seats 103 corresponding to the load-bearing platform 101 and the rigid plate 105.

[0039] like Figure 2 , Figure 3 As shown, the secretary bird wing module is installed symmetrically on the left and right sides of the load-bearing platform 101, including a horizontal connecting seat 201, a flexible plate 202 and a second viscoelastic damping layer 203. The flexible plate 202 is a uniform rectangular hollow slender plate, which is fixed on the load-bearing platform 101 through the horizontal connecting seat 201, and the second viscoelastic damping layer 203 is bonded to the lower surface of the flexible plate 202.

[0040] The secretary bird lower limb module comprises a diamond structure consisting of a short connecting rod 108, a long connecting rod 109, a middle connecting rod 111, a second tension spring 110, a connecting base 112, and a pressure spring 113; one end of the two short connecting rods 108 is connected to the center point of the lower surface of the load-bearing platform 101 through a fixed support, the other end of the two short connecting rods 108 is respectively hinged to one end of the two long connecting rods 109, the other end of the two long connecting rods 109 is respectively hinged to one end of the two middle connecting rods 111, and the other end of the two middle connecting rods 111 is hinged to the upper end of the connecting base 112; the connecting base 112 The bottom end is fixedly connected to the base 114; the middle and upper parts of the two long connecting rods 109 are hinged together, and the length of the shorter of the two sections cut by the short connecting rod 108 and the long connecting rod 109 at the connection point is equal, thereby forming a small diamond structure at the upper part of the secretary bird lower limb module; the length of the longer of the two sections cut by the middle connecting rod 111 and the long connecting rod 109 at the connection point is equal, thereby forming a large diamond structure at the lower part of the secretary bird lower limb module; a second tension spring 110 is provided between the two horizontal connection points of the large diamond structure, and a pressure spring 113 is provided on the connecting base 112.

[0041] The length ratio of the short connecting rod 108 , the long connecting rod 109 and the middle connecting rod 111 is selected as 1:3.5:2.5 based on the ratio of the femur, tibia and tarsometatarsus of the secretary bird's leg.

[0042] The structure of the connecting base 112 is as follows: a cylinder 601 is sleeved on a cylinder 603, the bottom of the cylinder 603 is fixedly connected to a downward support platform 604, the downward support platform 604 is fixedly connected to the base 114, the outer surface of the cylinder 601 is provided with an extended support circular surface 602, and the pressure spring 113 is provided between the extended support circular surface 602 and the downward support platform 604. Figure 7 shown.

[0043] The working principle of the secretary bird-like nonlinear vibration isolator of the present invention is described below:

[0044] When an object requiring vibration isolation is placed on the load-bearing platform 101, the platform 101 moves downward. Because the connecting rods within the two diamond-shaped structures are hinged and can rotate, under the pressure of the object, the connecting rods move vertically toward each other, compressing the diamond structure. This is the process by which the legs used for support when the secretary bird hunts bend outward. At the same time, because the two ends of the second tension spring 110 are respectively hooked onto the bolts at the two connecting points in the middle of the large diamond structure, the second tension spring 110 extends along its length as the diamond structure compresses. The pressure spring 113 at the bottom also shortens under the pressure of the object. This keeps the entire vibration isolator within a relatively low dynamic stiffness range to meet the requirements of isolating the vibration source of the base 114. When subjected to vibration excitation, in the first embodiment, the rigid plate 105 and the load-bearing platform 101 are connected by a hinge 104, and the vertical connecting seat 103 is connected by a tension spring 107. The rigid plate 105 provides inertial force as the load-bearing platform 101 swings up and down. In addition, the first viscoelastic damping layer 106 itself has a vibration-absorbing effect, which in turn further reduces the vibration of the load-bearing platform 101. In the second solution, the flexible plate 202 can swing up and down directly with the load-bearing platform 101, providing an inertial force. In addition, the second viscoelastic damping layer 203 itself has a vibration-absorbing effect, which in turn further reduces the vibration of the load-bearing platform 101. When the object to be isolated is removed, the two diamond structures reset under the tension of the second tension spring 110, and the pressure spring 113 also returns to its original position at the same time after it is no longer loaded, and finally the vibration isolator returns to its original position.

[0045] The advantages of the first solution are that the materials required for the secretary bird wing module are readily available, the rigid panels are connected to the support platform via hinges, allowing for better swinging, and the device is less susceptible to environmental interference, allowing it to operate under complex conditions. The advantages of the second solution are that the secretary bird wing module is more compact than the first solution, with the flexible panels abutting the support platform via horizontal connectors, allowing it to be considered a single unit.

[0046] The above describes the principles of the present invention and two specific embodiments. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other in any manner.

Claims

1. A secretary bird-like nonlinear vibration isolator, characterized in that: The invention comprises a load-bearing platform (101), a limiting device (102), a wing module, a lower limb module and a base (114); the limiting devices (102) are four and are respectively installed on the four corners of the load-bearing platform (101) and the base (114); the wing modules are installed on both sides of the load-bearing platform (101); the lower limb modules are installed between the load-bearing platform (101) and the base (114), and are axially symmetrically distributed about the vertical center line of the load-bearing platform (101); The wing module includes a rigid plate (105) and a first tension spring (107), one end of the rigid plate (105) is connected to the load-bearing platform (101) via a hinge (104), and the first tension spring (107) is installed between the load-bearing platform (101) and the rigid plate (105); or the wing module includes a flexible plate (202), one end of the flexible plate (202) is fixed on the load-bearing platform (101); The lower limb module comprises a rhombus structure consisting of a short connecting rod (108), a long connecting rod (109), a middle connecting rod (111), a second tension spring (110), a connecting base (112), and a pressure spring (113); one end of the two short connecting rods (108) is connected to the center point of the lower surface of the load-bearing platform (101) through a fixed support, the other end of the two short connecting rods (108) is hinged to one end of the two long connecting rods (109), the other end of the two long connecting rods (109) is hinged to one end of the two middle connecting rods (111), and the other end of the two middle connecting rods (111) is hinged to the upper end of the connecting base (112); the connecting rod The bottom end of the connecting base (112) is fixedly connected to the base (114); the middle and upper parts of the two long connecting rods (109) are hinged together, and the length of the shorter of the two sections cut by the connecting point of the short connecting rod (108) and the long connecting rod (109) is equal, thereby forming a small diamond structure at the upper part of the lower limb module; the length of the longer of the two sections cut by the connecting point of the middle connecting rod (111) and the long connecting rod (109) is equal, thereby forming a large diamond structure at the lower part of the lower limb module; a second tension spring (110) is provided between the two horizontal connection points of the large diamond structure, and a pressure spring (113) is provided on the connecting base (112).

2. The secretary bird-like nonlinear vibration isolator according to claim 1, characterized in that: The wing module is symmetrically installed on the left and right sides of the load-bearing platform (101), and includes a vertical connecting seat (103), a hinge (104), a rigid plate (105), a first viscoelastic damping layer (106), and a first tension spring (107); the rigid plate (105) is narrower than the load-bearing platform (101) and is a uniform rectangular hollow slender plate; one end of the rigid plate (105) is connected to the load-bearing platform (101) through a hinge (104), the first viscoelastic damping layer (106) is bonded to the lower surface of the rigid plate (105), and the upper surface of the rigid plate (105) is The two vertical connecting seats (103) on the upper surface are distributed at the two corners of the hinged end of the rigid plate (105); the two vertical connecting seats (103) on the upper surface of the load-bearing platform (101) are distributed at the edge position of the load-bearing platform (101) on the same horizontal line as the vertical connecting seats (103) on the rigid plate (105); the vertical connecting seats (103) on the lower surface of the rigid plate (105) and the load-bearing platform (101) are distributed symmetrically with the upper surface; and a first tension spring (107) is installed on the vertical connecting seats (103) corresponding to the load-bearing platform (101) and the rigid plate (105).

3. The secretary bird-like nonlinear vibration isolator according to claim 1, characterized in that: The wing module is symmetrically installed on the left and right sides of the load-bearing platform (101), and comprises a horizontal connecting seat (201), a flexible plate (202) and a second viscoelastic damping layer (203). The flexible plate (202) is a uniform rectangular hollow slender plate, which is fixed on the load-bearing platform (101) through the horizontal connecting seat (201). The second viscoelastic damping layer (203) is bonded to the lower surface of the flexible plate (202).

4. The secretary bird-like nonlinear vibration isolator according to claim 1, characterized in that: The length ratio among the short connecting rod (108), the long connecting rod (109) and the middle connecting rod (111) is selected as 1:3.5:2.

5.

5. The secretary bird-like nonlinear vibration isolator according to claim 1, characterized in that: The structure of the connecting base (112) is as follows: a cylinder (601) is sleeved on a column (603); the bottom of the cylinder (603) is fixedly connected to a downward extension support platform (604); the downward extension support platform (604) is fixedly connected to the base (114); the outer surface of the cylinder (601) is provided with an extended support circular surface (602); and the pressure spring (113) is provided between the extended support circular surface (602) and the downward extension support platform (604).

Images