Load-adjustable X-type quasi-zero stiffness pipeline support

Abstract

The invention provides a load-adjustable X-shaped quasi-zero stiffness pipeline support, which relates to the technical field of pipeline supports, and comprises an upper plate shell, a lower plate shell, a vertical spring, a hinge shaft, a connecting rod, a support, a horizontal spring, a vertical spring adjusting mechanism, a spring pre-tightening module and a gear. The positive / negative stiffness elements are separately arranged, so that mutual interference of traditional parallel springs is avoided; and meanwhile, the problem of clamping stagnation of a lower dead center below static displacement of a traditional shear type mechanism is solved through forced movement constraint. By arranging the threaded rod-sliding block mechanism, continuous bearing load adjustment is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pipeline support, in particular, especially to an X-shaped quasi-zero stiffness pipeline support with adjustable load. BACKGROUND

[0002] Currently, the ship power system operates in a complex and variable working condition environment, and its pipeline system is often excited by multiple vibration sources. How to effectively suppress and alleviate the negative effects of such vibration loads on thermal power systems has become one of the key technical problems to be broken through in the field of ship power technology. At the same time, the design of the ship power pipeline support structure needs to meet the requirements of vibration reduction and load bearing.

[0003] In terms of vibration reduction, the traditional vibration reduction structure is still widely used in ships at present, but the traditional support and hanger vibration reduction structure, such as spring support and hanger, three-bar constant force support and hanger, etc., has good effect on medium and high frequency vibration reduction, but poor effect on low frequency vibration reduction in the range of 0.1 Hz~20 Hz. It is difficult to deal with the problem of low frequency vibration isolation.

[0004] In order to reduce the natural frequency, the static stiffness can be reduced, but it is found that the displacement is too large and the load bearing capacity is reduced. The quasi-zero stiffness (QZS) nonlinear vibration isolator breaks the contradiction between large static load capacity and low dynamic stiffness in traditional linear vibration isolation, thereby realizing ultra-low effective vibration isolation frequency band.

[0005] High static low dynamic stiffness (HSLDS) and quasi-zero stiffness (QZS) vibration isolation technology connects linear vibration isolator and negative stiffness mechanism in parallel, uses negative stiffness to offset positive stiffness, so that the system has high static stiffness and low dynamic stiffness characteristics at static balance position. The principle is shown in Figure 1 When the dynamic stiffness tends to zero, the quasi-zero stiffness (QZS) vibration isolator is formed, which can significantly reduce the displacement transmissibility in the whole frequency band, while maintaining the advantage of small static displacement. It shows breakthrough vibration isolation performance in low frequency vibration sensitive scenes such as ship pipeline and power system equipment. SUMMARY

[0006] According to the technical problems mentioned in the above background technology, an X-shaped quasi-zero stiffness pipeline support with adjustable load is provided.

[0007] The technical means adopted by the present application are as follows: An X-shaped quasi-zero stiffness pipeline support with adjustable load comprises: an upper plate shell, a lower plate shell, a vertical spring, a hinge shaft, a connecting rod, a support, a horizontal spring, a vertical spring adjusting mechanism and a spring pre-tightening module; The vertical spring adjusting mechanism comprises a threaded rod and a spring mounting support. The spring pre-tightening module comprises an adjusting nut and a level patch. The upper plate shell top is provided with a preset threaded hole connected with a pipeline load bearing groove structure; the lower plate shell is also provided with a preset threaded hole as the upper plate shell; the connecting rods are arranged on the lower plate shell, and two connecting rods are symmetrically arranged and connected through the hinge shaft; the connecting rods are fixed on the support; The vertical spring is compressed to 80% of the rated load through the adjusting nut, and the horizontal state of the support is calibrated through the spirit level patch; the installation spacing of the vertical spring is synchronously adjusted using the rotating threaded rod until all the connecting rods are in the same horizontal plane, i.e. in the static balance position; In the static balance state, when the pipeline load reaches the rated mass, the positive stiffness restoring force generated by the vertical spring and the negative stiffness restoring force converted by the horizontal spring through the shear type connecting rod mechanism are mutually offset, i.e. the stiffness tends to be zero; the meshing of the gear realizes the movement coordination of the connecting rod below the static balance position; In the dynamic response and adjustment, when the pipeline is subjected to vertical impact, the vertical spring is compressed and the horizontal spring is stretched, and the negative stiffness compensation is realized through the change of the connecting rod angle to inhibit the vibration transmission; if the load mass changes, the effective length of the vertical spring is changed through the rotating adjusting knob, so that the stiffness is adjusted to realize the self-adaptive adjustment under different working conditions.

[0008] Further, the pipeline is fixed on the pipeline load bearing groove structure connected with the upper plate shell, and the center line of the pipeline is ensured to coincide with the axis of the vertical spring.

[0009] Further, the upper plate shell and the lower plate shell are both made of 6061 aluminum alloy.

[0010] Further, the vertical spring is a single set of variable-pitch cylindrical spiral spring; the stiffness coefficient of the vertical spring is .

[0011] Further, the support includes four self-lubricating copper sleeve sliding bearings and gears.

[0012] Further, the change of the connecting rod angle is ≤45°.

[0013] Compared with the prior art, the present application has the following advantages: The present application separates the positive / negative stiffness elements and avoids the mutual interference of the traditional parallel springs; at the same time, the problem of lower stop point jamming under the static displacement of the traditional shear type mechanism is solved through forced motion constraint. The present application realizes continuous load adjustment through the threaded rod-sliding block mechanism.

[0014] Based on the comparative study of the system based on parameters 、 , ζ , it is shown that: The quasi-zero stiffness system is constructed by connecting the nonlinear pipe support and damper in parallel, and has high static stiffness (stable support rated load) and equivalent low dynamic stiffness. The restoring force model can be characterized as a nonlinear function is a linear stiffness coefficient, is a cubic nonlinear stiffness coefficient), compared with the traditional linear system which only relies on The harmonic balance method shows that the system in the low frequency stage The multi-stable response induced by the nonlinear stiffness term significantly changes the dynamic behavior, so that the quasi-zero stiffness system can also isolate vibration in the low frequency stage, and it is full frequency isolation, which greatly improves the performance of the original isolator. The characteristics of the invention are derived from the topological reconstruction of the potential energy surface of the system by nonlinear stiffness, which realizes the adaptive adjustment of dynamic stiffness while ensuring static bearing. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0016] Figure 1 It is a schematic diagram of the principle of the high static low dynamic stiffness isolator in the background art.

[0017] Figure 2 It is a three-dimensional schematic diagram of the device of the present application.

[0018] Figure 3 It is an enlarged view of the negative stiffness mechanism of the present application.

[0019] Figure 4 It is a schematic diagram of the meshing state profile of the gear of the present application.

[0020] Figure 5 It is a schematic diagram of the motion below the static equilibrium point of the present application.

[0021] Figure 6 It is a schematic diagram of the vertical spring adjusting mechanism of the present application.

[0022] Figure 7 It is a schematic diagram of the aluminum alloy connecting rod of the present application.

[0023] Figure 8 It is a schematic diagram of the vertical spring warning module of the present application.

[0024] Figure 9 It is a schematic diagram of the dynamics simulation of the present application.​

[0025] Figure 10 Simulation diagram of isolation frequency of X-QZS in the present application under different load masses Figure 1 .

[0026] Figure 11 Simulation diagram of isolation frequency of X-QZS in the present application under different load masses Figure 2 Wherein, 1, upper plate shell; 2, lower plate shell; 3, vertical spring; 4, hinge shaft; 5, connecting rod; 6, bracket; 7, horizontal spring; 8, vertical spring adjusting mechanism; 8a, threaded rod; 8b, spring mounting support; 9, spring pre-tightening module; 9a, adjusting nut; 9b, level patch; 10, gear. DETAILED DESCRIPTION

[0027] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0028] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should also be understood that when the terms "comprise" and / or "include" are used in the specification, there is a feature, step, operation, device, component and / or combination thereof.

[0030] The foregoing is considered as illustrative only of the principles of the application. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the application to the exact construction and practice described. Accordingly, all such variations are intended to be included within the scope of the present application as defined in the following claims, along with full equivalents thereof.

[0031] In the description of the present application, it is to be understood that the orientation terms such as "front", "back", "up", "down", "left", "right", "transverse", "vertical", "horizontal", "top", "bottom", etc. indicate the orientation or positional relationship shown in the drawings, which are merely for the convenience of describing and simplifying the present application, and do not indicate or imply that the devices or elements referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the present application. The orientation terms "inner", "outer" refer to the inner and outer relative to the contour of the components themselves.

[0032] For the convenience of description, spatial relative terms such as "over", "above", "upper surface", "upper", etc. can be used herein to describe the spatial positional relationship of one device or feature with respect to other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the devices described in the drawings. For example, if the devices in the drawings are inverted, the device described as "above" or "over" other devices or structures will be positioned "below" or "under" the other devices or structures. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0033] In addition, it should be noted that the use of the terms "first", "second", etc. to qualify parts of components is merely for the convenience of distinguishing the corresponding parts of components, and the above terms have no special meaning unless otherwise stated, and therefore cannot be understood as limiting the scope of protection of the present application.

[0034] As Figures 2-11The present invention provides an adjustable load X-type quasi-zero stiffness pipe support, comprising: an upper plate housing 1, a lower plate housing 2, a vertical spring 3, a hinge shaft 4, a connecting rod 5, a support 6, a horizontal spring 7, a vertical spring adjustment mechanism 8, a spring preload module 9, and a gear 10; the vertical spring adjustment mechanism includes a threaded rod 8a and a spring mounting bracket 8b; the spring preload module 9 includes an adjusting nut 9a and a level plate 9b.

[0035] The upper plate outer shell 1 has a pre-set threaded hole at the top that is connected to the pipe load-bearing groove structure; the lower plate outer shell 2 also has a pre-set threaded hole as the upper plate outer shell 1; the connecting rod 5 is set on the lower plate outer shell 2, and two connecting rods 5 are symmetrically arranged, and the two connecting rods 5 are connected by the hinge shaft 4; the connecting rod 5 is fixed on the bracket 6; First, install and initially set up the pipe by fixing it to the pipe-bearing groove structure connected to the upper shell 1, ensuring that the pipe centerline coincides with the axis of the vertical spring 3. Then, compress the vertical spring 3 to 80% of its rated load using the adjusting nut 9a of the spring preload module 9, and calibrate the bracket's level using the leveling plate 9b. Finally, use the vertical spring adjusting mechanism 8 to rotate the threaded rod 8a, simultaneously adjusting the installation spacing of the vertical springs until all connecting rods 5 are on the same horizontal plane (static equilibrium position). In static equilibrium, when the pipe load reaches the rated mass, the normal stiffness restoring force generated by the vertical spring 3... The negative stiffness restoring force of the horizontal spring 7 is converted through a scissor linkage mechanism. The components cancel each other out, bringing the overall system stiffness close to zero. Simultaneously, the meshing design of gear 10 optimizes the motion coordination of the connecting rod below the static equilibrium position, avoiding dead zone issues. In dynamic response and adjustment, when the pipe is subjected to a vertical impact, the vertical spring compresses and the horizontal spring stretches, which is controlled by changes in the connecting rod angle (…). This achieves negative stiffness compensation to suppress vibration transmission; if the load mass changes, the effective length of the vertical spring can be changed by rotating the adjustment knob 8a. (n is the knob scale number), thereby adjusting the system stiffness. It enables adaptive adjustment under different operating conditions.

[0036] Preferably, both the upper shell 1 and the lower shell 2 are made of 6061 aluminum alloy.

[0037] In this application, the vertical spring 3 is a single-set variable pitch cylindrical helical spring; the stiffness coefficient of the vertical spring 3 .

[0038] Preferably, in this application, the bracket 6 includes four sliding bearings with self-lubricating copper sleeves and gears.

[0039] As preferred, the connecting rods are 8 pieces of 6061 aluminum alloy; length L = 88 mm, cross-section thickness 7 mm.

[0040] The dynamic simulation shows that when ζ = 0.02, the sweep frequency analysis finds that the higher static and lower dynamic system is closer to the quasi-zero stiffness system, the better the vibration isolation effect is; in the fixed frequency experiment, compared with the linear system, the starting isolation frequency of the X-QZS system is reduced from 3.27 Hz to 0.13 Hz, which is reduced by 90.33%, and the vibration isolation effect is obvious.

[0041] When the load changes, the transmissibility peak of the linear system decreases when the load mass decreases, but the starting isolation frequency increases; the transmissibility peak of the general X-QZS increases when the load mass deviates from the rated mass; but when the load mass of the X-LAQZS system changes to 160 Kg and 140 Kg respectively, the starting isolation frequency is reduced by 89.76% and 90.51% respectively. It shows that the load adjustable quasi-zero stiffness system is better than the general quasi-zero stiffness system in the vibration isolation effect, and can be used for the low frequency vibration isolation of the pipeline of the ship power system.

[0042] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An adjustable load X-type quasi-zero stiffness pipe support, characterized by, The utility model relates to a pipeline damping device, which comprises an upper plate shell (1), a lower plate shell (2), a vertical spring (3), a hinge shaft (4), a connecting rod (5), a support (6), a horizontal spring (7), a vertical spring adjusting mechanism (8), a spring pre-tightening module (9) and a gear (10). The vertical spring adjusting mechanism comprises a threaded rod (8a) and a spring mounting support (8b), and the spring pre-tightening module (9) comprises an adjusting nut (9a) and a level patch (9b). The upper plate shell (1) is connected to a pipeline load-bearing groove structure through a preset threaded hole at the top, and the lower plate shell (2) is also provided with a threaded hole. The vertical spring (3) is compressed to 80% of the rated load through the adjusting nut (9a), and the horizontal state of the support is calibrated through the level patch (9b); the installation spacing of the vertical spring is adjusted synchronously through the rotating threaded rod (8a) until all the connecting rods (5) are in the same horizontal plane, i.e., in a static equilibrium position. In the static equilibrium state, when the pipeline load reaches the rated mass, the positive stiffness restoring force generated by the vertical spring (3) and the negative stiffness restoring force converted by the horizontal spring (7) through the scissors linkage mechanism are mutually offset, i.e., the stiffness tends to be zero; the meshing of the gear (10) realizes the movement coordination of the connecting rod below the static equilibrium position. In dynamic response and adjustment, when the pipeline is subjected to vertical impact, the vertical spring is compressed and the horizontal spring is stretched, and the negative stiffness compensation is realized through the change of the connecting rod angle to suppress vibration transmission; if the load mass changes, the effective length of the vertical spring is changed through the rotating adjusting knob (8a), so as to adjust the stiffness and realize self-adaptive adjustment under different working conditions. The pipeline is fixed to the pipeline load-bearing groove structure connected to the upper plate shell (1), and the center line of the pipeline coincides with the axis of the vertical spring (3).

2. An adjustable load X-type quasi-zero stiffness pipe support according to claim 1, wherein, The upper plate shell (1) and the lower plate shell (2) are both made of 6061 aluminum alloy.

3. An adjustable load X-type quasi-zero stiffness pipe support according to claim 1, wherein, The support (6) comprises four self-lubricating copper sleeve sliding bearings and gears.

4. An adjustable load X-prime zero stiffness pipe support according to claim 1, wherein, The vertical spring (3) is a single set of variable-pitch cylindrical helical spring; the stiffness coefficient of the vertical spring (3) is .

5. An adjustable load X-prime zero stiffness pipe support according to claim 1, wherein, ​ 6. An adjustable load X-tube pipe support according to claim 1, wherein, The link angle change .

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