Asymmetric Stokes Brill damper with multiple resonant frequencies

Abstract

The invention discloses an asymmetric Stokes Brill damper with multiple resonant frequencies, which comprises a clamping assembly and two groups of weight assemblies, each group of weight assembly comprises a weight with a U-shaped structure and a bearing cable, and the far end of the bearing cable is fixedly connected to the middle section of the opening side of the weight; the top of the clamping assembly is buckled and hung on the overhead transmission line, the bottom of the clamping assembly is fixedly connected with the near ends of the bearing cables of the two sets of counterweight assemblies. The damper has a multi-resonant-frequency asymmetric structure that utilizes tuned mass to counteract wind power vibrations of an overhead transmission line to absorb and dissipate energy that may cause damage or destruction, in order to "push" structural motion of the overhead transmission line during the vibrations, thereby reducing the vibrations.

Description

Technical Field

[0001] The invention relates to the technical field of cable vibration prevention, and in particular to an asymmetric Stockbridge damper with multiple resonance frequencies. Background Art

[0002] Stockbridge damper is a tuned mass damper used to dampen wind-induced vibrations on long overhanging slender structures. This dumbbell-shaped device consists of two masses located at either end of a short length of cable or flexible rod, which is clamped to the main cable in the middle. This damper is used to dissipate the vibration energy of the main cable to acceptable levels. Its unique shape has earned it the nickname of "dog bone damper". These dampers are used to counteract wind-induced vibrations, so-called Karman vibrations. There are several different types of dampers available, depending on the type of overhead transmission line conductor. This damper got its name from scientist H. Stockbridge, who promoted the development of dampers in the 1920s. Its mode of operation remains unchanged to this day and is one of the most common methods of reducing vibrations in overhead transmission lines.

[0003] However, at present, the Stockbridge damper is still difficult to use in wind-proof and vibration-reducing processing of power transmission lines due to its uneven structural layout. Summary of the invention

[0004] The purpose of the present invention is to solve the deficiencies of the prior art and to propose an asymmetric Stockbridge damper with multiple resonant frequencies. The damper has an asymmetric structure with multiple resonant frequencies, utilizes tuning mass to offset wind vibrations of overhead transmission lines, and has a simple structure and is easy to implement.

[0005] The present invention discloses an asymmetric Stockbridge damper with multiple resonance frequencies, comprising a clamping assembly and two sets of counterweight assemblies, each set of counterweight assemblies comprising a weight block of a U-shaped structure and a load-bearing cable, the distal end of the load-bearing cable being fixedly connected to the middle section of the opening side of the weight block; the top of the clamping assembly is buckled and hung on the overhead transmission line, wherein the top of the clamping assembly is buckled and hung on the overhead transmission line, and the bottom of the clamping assembly is fixedly connected to the proximal ends of the load-bearing cables of the two sets of counterweight assemblies.

[0006] Preferably, the counterweight assembly comprises a first assembly and a second assembly, wherein:

[0007] The first component includes a first main counterweight, a first beam and a second beam are respectively fixedly provided at both ends of a side wall of the first main counterweight, wherein the distal end of the first beam is fixedly connected to the first secondary counterweight, and the distal end of the second beam is fixedly connected to the second secondary counterweight;

[0008] The second component includes a second main counterweight, and a third beam and a fourth beam are respectively fixedly provided at both ends of a side wall of the second main counterweight, wherein the far end of the third beam is fixedly connected to a third secondary counterweight, and the far end of the fourth beam is fixedly connected to a fourth secondary counterweight.

[0009] According to claim 2, an asymmetric Stockbridge damper with multiple resonance frequencies is characterized in that the volume and weight relationship of the first-stage counterweight, the second-stage counterweight, the third-stage counterweight and the fourth-stage counterweight are as follows: the first-stage counterweight> the third-stage counterweight> the second-stage counterweight> the fourth-stage counterweight.

[0010] Preferably, receiving holes for fixing and inserting load-bearing cables are provided in the middle parts of the opposite side walls of the first main counterweight and the second main counterweight.

[0011] An asymmetric Stockbridge damper with multiple resonance frequencies according to claim 4, characterized in that the load-bearing cable comprises a first load-bearing cable and a second load-bearing cable;

[0012] The proximal end of the first load-bearing cable is covered and fixed by the bottom end of the clamping assembly, and the distal end of the first load-bearing cable is fixedly connected to the receiving hole of the first main counterweight block;

[0013] The proximal end of the second load-bearing cable is covered and fixed by the bottom end of the clamping assembly, and the distal end of the second load-bearing cable is fixedly connected to the inside of the receiving hole of the second main counterweight block.

[0014] Preferably, the lower part of the clamping assembly is a base serving as the main body of the clamping assembly, the lower part of the base is integrally provided with a load-bearing sling shell that covers and fixes the load-bearing cables at both ends, and the upper part of the base is integrally provided with a middle body; symmetrically arranged support arms are integrally formed on the side wall of the middle body, transversely penetrating bolt holes are provided on the middle body, and an inclined bent neck is integrally formed on the top of the middle body; symmetrically arranged guide rails are integrally formed on the side wall of the neck, and a downwardly bent chuck is integrally provided on the top of the neck; a curved surface is provided on the bottom surface of the chuck, and a rubber sleeve is compositely bonded to the curved surface.

[0015] Preferably, a toggle crank is rotatably sleeved on the spring pin, the top end of the toggle crank is integrally formed with an arc-shaped cam surface, and a through hole with a hole diameter larger than the bolt hole is opened on the toggle crank; a bolt is penetrated and connected in the through hole, the middle section of the bolt penetrates the bolt hole on the middle body, and the threaded end of the bolt is engaged and sleeved with a nut for adjusting the distance between the middle body and the toggle crank.

[0016] Preferably, a slider is inserted into the guide rail in a sliding guide in the extension direction of the neck, the bottom surface of the slider is made into an inclined surface that slides with the cam surface of the elbow crank, and a movable clamping part that cooperates with the clamp to clamp the overhead transmission line is integrally formed on one side of the upper part of the slider; the top surface of the movable clamping part is made into a curved surface, and a rubber lining is compositely bonded to the curved surface.

[0017] The advantages and technical effects of the present invention are:

[0018] The present invention discloses an asymmetric Stockbridge damper with multiple resonant frequencies. The damper has an asymmetric structure with multiple resonant frequencies and utilizes tuned mass to offset wind vibrations of overhead transmission lines to absorb and dissipate energy that may cause damage or destruction. The damper is intended to "push" the structural movement of the overhead transmission lines during vibrations, thereby reducing vibrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention (top view);

[0020] Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention (looking up);

[0021] Figure 3 for Figure 2 A cross-sectional view at 8-8;

[0022] Figure 4 Schematic diagram of the three-dimensional structure of the first component in the present invention (Example 1)

[0023] Figure 5 Schematic diagram of the three-dimensional structure of the first component in the present invention (Example 2)

[0024] Figure 6 Schematic diagram of the three-dimensional structure of the first component in the present invention (Example 3)

[0025] Figure 7 Schematic diagram of the three-dimensional structure of the first component in the present invention (Example 4)

[0026] Figure 8 Schematic diagram of the three-dimensional structure of the first component in the present invention (Example 5)

[0027] Fig. 9 It is a schematic diagram of the exploded structure of the clamping assembly in the present invention;

[0028] Fig.10 It is a side view of the clamping assembly in the present invention (the toggle crank is not tightened);

[0029] Fig.11 It is a side view of the clamping assembly in the present invention (in the toggle crank tightening posture);

[0030] In the figure: 100 - first component; 110 - first load-bearing cable; 120 - first main counterweight; 130 - first beam; 140 - second beam; 150 - first secondary counterweight; 160 - second secondary counterweight; 170 - receiving hole;

[0031] 20-overhead transmission line; 200-second assembly; 210-second traction cable; 220-second main counterweight; 230-third beam; 240-fourth beam; 250-third auxiliary weight; 260-fourth auxiliary weight;

[0032] 300-clamping assembly; 310-clamp body; 320-slider; 330-toggle crank assembly; 340-base; 345-middle body; 350-neck; 355-chuck; 360-load-bearing sling housing; 365-support arm; 370-mounting hole; 375-guide rail; 377-curved surface; 380-rubber sleeve; 385-base;

[0033] 410 - movable clamping part; 415 - curved surface; 420 - rubber lining; 450 - elbow crank; 455 - spring pin; 460 - bolt; 465 - slot; 470 - hole; 475 - nut;

[0034] 510 - cam surface; 515 - inclined surface. DETAILED DESCRIPTION

[0035] The embodiments of the invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the invention, and cannot be understood as limiting the invention.

[0036] The present invention discloses an asymmetric Stockbridge damper with multiple resonance frequencies, comprising a clamping assembly and two sets of counterweight assemblies, each set of counterweight assemblies comprising a weight block of a U-shaped structure and a load-bearing cable, the distal end of the load-bearing cable being fixedly connected to the middle section of the opening side of the weight block; the top of the clamping assembly is buckled and hung on the overhead transmission line, wherein the top of the clamping assembly is buckled and hung on the overhead transmission line, and the bottom of the clamping assembly is fixedly connected to the proximal ends of the load-bearing cables of the two sets of counterweight assemblies.

[0037] Preferably, the counterweight assembly comprises a first assembly and a second assembly, wherein:

[0038] The first component includes a first main counterweight, a first beam and a second beam are respectively fixedly provided at both ends of a side wall of the first main counterweight, wherein the distal end of the first beam is fixedly connected to the first secondary counterweight, and the distal end of the second beam is fixedly connected to the second secondary counterweight;

[0039] The second component includes a second main counterweight, and a third beam and a fourth beam are respectively fixedly provided at both ends of a side wall of the second main counterweight, wherein the far end of the third beam is fixedly connected to a third secondary counterweight, and the far end of the fourth beam is fixedly connected to a fourth secondary counterweight.

[0040] According to claim 2, an asymmetric Stockbridge damper with multiple resonance frequencies is characterized in that the volume and weight relationship of the first-stage counterweight, the second-stage counterweight, the third-stage counterweight and the fourth-stage counterweight are as follows: the first-stage counterweight> the third-stage counterweight> the second-stage counterweight> the fourth-stage counterweight.

[0041] Preferably, receiving holes for fixing and inserting load-bearing cables are provided in the middle parts of the opposite side walls of the first main counterweight and the second main counterweight.

[0042] An asymmetric Stockbridge damper with multiple resonance frequencies according to claim 4, characterized in that the load-bearing cable comprises a first load-bearing cable and a second load-bearing cable;

[0043] The proximal end of the first load-bearing cable is covered and fixed by the bottom end of the clamping assembly, and the distal end of the first load-bearing cable is fixedly connected to the receiving hole of the first main counterweight block;

[0044] The proximal end of the second load-bearing cable is covered and fixed by the bottom end of the clamping assembly, and the distal end of the second load-bearing cable is fixedly connected to the inside of the receiving hole of the second main counterweight block.

[0045] Preferably, the lower part of the clamping assembly is a base serving as the main body of the clamping assembly, the lower part of the base is integrally provided with a load-bearing sling shell that covers and fixes the load-bearing cables at both ends, and the upper part of the base is integrally provided with a middle body; symmetrically arranged support arms are integrally formed on the side wall of the middle body, transversely penetrating bolt holes are provided on the middle body, and an inclined bent neck is integrally formed on the top of the middle body; symmetrically arranged guide rails are integrally formed on the side wall of the neck, and a downwardly bent chuck is integrally provided on the top of the neck; a curved surface is provided on the bottom surface of the chuck, and a rubber sleeve is compositely bonded to the curved surface.

[0046] Preferably, a toggle crank is rotatably sleeved on the spring pin, the top end of the toggle crank is integrally formed with an arc-shaped cam surface, and a through hole with a hole diameter larger than the bolt hole is opened on the toggle crank; a bolt is penetrated and connected in the through hole, the middle section of the bolt penetrates the bolt hole on the middle body, and the threaded end of the bolt is engaged and sleeved with a nut for adjusting the distance between the middle body and the toggle crank.

[0047] Preferably, a slider is inserted into the guide rail in a sliding guide in the extension direction of the neck, the bottom surface of the slider is made into an inclined surface that slides with the cam surface of the elbow crank, and a movable clamping part that cooperates with the clamp to clamp the overhead transmission line is integrally formed on one side of the upper part of the slider; the top surface of the movable clamping part is made into a curved surface, and a rubber lining is compositely bonded to the curved surface.

[0048] In order to more clearly illustrate the specific embodiments of the present invention, several embodiments are provided below:

[0049] 1. A clamp for securing the shock absorber to the line at a connection point on the curve, the clamp comprising first and second opposing sides;

[0050] The clamp includes: a clamp body including a sling housing to which each of the first and second load-bearing cables is fixed; a clamp head which can partially surround the flexible curve and is a first clamping surface; a slider movable to engage and disengage with the wire to capture the wire on the clamp head, the slider being a second clamping surface facing the first clamping surface, the slider including a low friction surface engaged with the clamp body to facilitate sliding movement of the slider relative to the clamp body; and a toggle crank pivotally mounted to the clamp body and including a cam surface in contact with the slider; and an actuator for moving the slider to engage and disengage with the wire. The slider mounted on the clamp body can be linearly moved relative to the clamp body and the clamp head to engage and disengage with the wire. The actuator includes a pivot member pivotally coupled to the clamp body, and a fastener engaging the clamp body and the pivot member to pivot the pivot member in a tightening direction and a loosening direction, and movement of the pivot member in the tightening direction causes the slider to move to engage with the wire, and movement of the pivot member in the loosening direction causes the slider to move to engage with the wire, and movement of the pivot member in the loosening direction causes the slider to move to disengage from the wire, the actuator is used to pivot the toggle crank toward the clamp body so that interaction of the cam surface with the slider causes the slider to slide toward the clamp head and generate a theoretically sufficient clamping force between the first and second clamping surfaces. The actuator also includes a bolt extending through the crank and threaded into the clamp body, and rotation of the bolt relative to the clamp body causes the bolt to move the crank toward the clamp body. The crank includes a slot through which the bolt extends, the slot accommodating the pivotal movement of the crank relative to the bolt. The clamp body includes an arm to which the crank is pinned to enable pivotal movement of the crank relative to the clamp body. The clamp also includes a pair of guide rails that limit movement of the slide block away from the clamp body and guide linear sliding movement of the clamp relative to the clamp body.

[0051] 2. A catenary and a counterweight, a first catenary extending parallel to a tangent of the curve at a connection point, the first catenary extending from a first side of the fixture to a first distal end; a second catenary extending parallel to a tangent of the curve at a connection point, the second catenary extending from a second side of the fixture to a second distal end; a first main counterweight interconnected with the first distal end of the first catenary; a second main counterweight interconnected with the second distal end of the second catenary; a first beam extending from the first main counterweight; a second beam extending from the first main counterweight; a third beam extending from the second main counterweight; a fourth beam extending from the second main counterweight; a first secondary counterweight connected to an end of the first beam; a second secondary counterweight connected to an end of the second beam; a third secondary counterweight connected to an end of the third beam; and a fourth secondary counterweight connected to an end of the fourth beam. The length of the first catenary of the damper is different from the length of the second catenary; the mass of the first main weight is different from the mass of the second main weight. The first and second main weights of the damper oscillate in a rotational direction about the longitudinal axes of the respective first and second catenary cables. The damper has a first beam extending from the first main weight to the first side of the clamp, a second beam extending from the first main weight to the first side of the clamp; a third beam extending from the second main weight to the second side of the clamp; a fourth beam extending from the second main weight to the second side of the clamp; the first and second beams extending parallel to the first load-bearing cable and located on opposite sides of the first load-bearing cable; the third and fourth beams extending parallel to the second load-bearing cable and located on opposite sides of the second load-bearing cable. Each of the first, second, third and fourth beams of the damper includes a large surface having a relatively large surface area and a small surface having a relatively small surface area, the large surface facing the line to which the damper is clamped; and the area moment of inertia of each beam about an axis perpendicular to the large surface is greater than the area moment of inertia about an axis perpendicular to the small surface. Each of the first, second, third and fourth secondary weights of the damper has a unique mass value; each of the first, second, third and fourth secondary weights has unique point mass oscillation characteristics, and each of the first, second, third and fourth secondary weights is spherical or any other concentrated geometric shape that maintains reasonable point mass characteristics.

[0052] Due to the above inventive design, the asymmetric Stockbridge damper with multiple resonance frequencies has six to ten different resonance frequencies.

[0053] Figure 1 and 2 An overhead transmission line 20 ( Figure 10-11A vibration damper 10 is provided (shown in FIG. 1 ). The vibration damper 10 may be applied to wires, cables or other tensioned wires (e.g., guy wires or wires in fences or building systems) that are subject to fatigue due to relatively low frequency vibrations. The vibration damper 10 is specifically designed to damp vibrations within the frequency range of wind vibrations. Wind vibrations can cause fatigue and eventual damage and failure of overhead transmission lines 20. This is the most common type of vibration in transmission lines and is caused by vortex shedding caused by laminar winds. These low amplitude vibrations are characterized by frequencies between 3-150 Hz. The vibrations occur in the vertical plane, creating alternating bending stresses and ultimately leading to failure of the conductor cable. The asymmetric Stockbridge damper 10 with multiple resonant frequencies is an improvement on the conventional Stockbridge damper and can be characterized as an asymmetric Stockbridge damper that extends the number of resonant frequencies above any known design of this type of damper.

[0054] The shock absorber 10 includes a first assembly 100 , a second assembly 200 , and a clamping assembly 300 connecting the first assembly 100 and the second assembly 200 . Figure 2 The vibration absorber 10 is shown in its intended operating position, wherein the clamp assembly 300 is clamped to the overhead power line 20 and the remainder of the vibration absorber 10 is suspended below the overhead power line 20. Spatial references such as "above", "below", "above", "below", etc. will be made relative to the normal operating position of the vibration absorber 10. When describing the components of the vibration absorber 10, the term "above" is used. Figure 1 and 2 The coordinate references (x, y, and z) shown in . Vertical motion occurs along the y-axis, while horizontal motion is usually along the x and z-axes. Rotation or torque about the corresponding axes is represented by x', y', and z'. As mentioned above, wind vibration operates in the vertical plane. This vibration in the vertical plane can be damped by up and down motion along the y-axis.

[0055] The basic construction of the first and second assemblies 100, 200 is substantially the same, except for the size and weight of the components, which results in a unique resonant frequency. Except for these size differences, which will be discussed below, the first and second assemblies 100, 200 are mirror images of each other. The first assembly 100 includes a first load-bearing cable 110, a first main counterweight 120, a first beam 130, a second beam 140, a first secondary counterweight 150, and a second secondary counterweight 160.

[0056] The overhead transmission line 20 assumes a curved state when it sags between the support structures, and the clamp assembly is connected to the overhead transmission line 20 at the connection point. In a static or intermediate position, the first load-bearing cable 110, the first beam 130 and the second beam 140 each extend parallel to the tangent of the curve at the connection point. For example, if the connection point is at the lowest point of the curve, the first load-bearing cable 110, the first beam 130 and the second beam 140 will be horizontal because the tangent at the bottom of the curve is generally horizontal. The following description assumes that the connection point is the bottom of the curve and the first load-bearing cable 110, the first beam 130 and the second beam 140 are horizontal, but in reality, the connection point may be located elsewhere on the curve of the overhead transmission line 20.

[0057] The first suspension cable 110, the first beam 130 and the second beam 140 each have a longitudinal axis substantially along the z-axis. The first traction cable 110 includes a proximal end 110p connected to the first side of the clamp assembly 300 and a distal end 110d connected to the first primary weight 120. The first beam 130 and the second beam 140 each include a proximal end 130p, 140p connected to the first primary weight 120 and a distal end 130d, 140d connected to the respective first and second secondary weights 150, 160. For reference, the origin of the local x, y and z coordinates is M1 (the proximal end 110p of the first traction cable 110, which is fixed to the clamp assembly 300), B1 (the proximal end 130p of the first beam 130) and B2 (the proximal end 140p of the second beam 140). The up and down motion of the first primary weight 120, the first secondary counterweight 150 and the second secondary weight 160 is not a purely vertical motion. In each case, the weights 120, 150, 160 describe an arc as the first load-bearing cable 110, the first beam 130 and the second beam 140 bend or flex (x' motion, referred to as "flexion") about the local x-axis at the origins M1, B1 and B2. Because the vertical component of this arcuate motion dominates within the designed range of motion, and only the vertical component is relevant to damping wind vibrations, for the purpose of the action of the asymmetric Stockbridge damper with multiple resonant frequencies, this motion is simply referred to as "vertical". The first load-bearing cable 110 can bend freely about all axes (x, y, z) centered on the origin M1, and can also twist (z' motion) about its longitudinal axis (z-axis). Only the bending x' about the local x-axis at the origin M1 (causing vertical motion of the first main weight) is relevant to wind vibrations. The first main weight 120 has the general shape of a rectangular block (i.e., generally rectangular sides and generally square ends). The first main weight 120 includes a major dimension extending horizontally, generally extending along the local x-axis. Therefore, the first main weight 120 can be characterized as being perpendicular to the first load-bearing cable 110. The first main weight 120 includes a receiving hole 170 on one side for receiving the distal end 110d of the first load-bearing cable 110. The distal end 110d of the first load-bearing cable 110 is fixed to the first main weight 120 in the receiving hole 170 by any suitable means (e.g., mechanical fasteners, press fit, adhesive). In connection with wind vibration damping, the first main weight 120 is free to move vertically at the distal end 110d of the first load-bearing cable 110. The first beam 130 and the second beam 140 extend from the first main weight 120 to the clamping assembly 300 parallel to the first cable 110 and extend on opposite sides of the first cable 110. Figure 1 and 2The first beam 130 and the second beam 140 shown have relatively wide and flat rectangular upper and lower sides and relatively thin rectangular side edges, in which respect the first beam 130 and the second beam 140 may be referred to as "thin beams". In other embodiments of the asymmetric Stockbridge damper with multiple resonant frequencies, the beams 130, 140 may have other shapes, but the maximum surface area should face the overhead transmission line 20. The area moment of inertia of each beam 130, 140 about the vertical axis (i.e., the axis perpendicular to the upper and lower sides) is greater than the area moment of inertia about the horizontal x and z axes. Therefore, each beam 130, 140 rigidly resists buckling (y' motion) about the vertical (y) axis at the origin B1, B2, and is more compliant or allows buckling (x' and z' motion) about the horizontal (x, z) axis. The first and second beams 130, 140 may be integrally formed with the first primary weight 120 and the corresponding first and second secondary counterweights 150, 160, or may be formed separately and connected to each other during assembly. The first secondary weight 150 and the second secondary weight 160 have unique mass values ​​(i.e., their masses are different from each other). The illustrated first secondary weight 150 and the second secondary weight 160 are spherical and behave like point masses. When an object is generally symmetrical about its center of mass, it behaves like a point mass, so that the main inertial force is translational, and the inertial rotational force around any axis passing through its center of mass is relatively insignificant. Such an object can be referred to as a concentrated shape. In other embodiments, as long as the secondary weights 150, 160 behave like point masses, they can have a concentrated shape or a non-spherical shape. Since the first and second secondary weights 150, 160 behave like point masses, they only apply inertial forces to the distal ends of the beams 130, 140 in the x, y, and z directions, and do not apply significant torque z' to the beams 130, 140 around the longitudinal axis of the beam. Since the moment of inertia of each beam 130, 140 about the y-axis is relatively high, and the secondary weights 150, 160 do not exert an inertial torque z' about the z-axis due to their point mass behavior, the inertial load of the secondary weights 150, 160 on the beams 130, 140 only causes the beams 130, 140 to bend x' about the x-axis centered at the origins B1 and B2. In other words, the only mode of motion of the secondary weights 150, 160 and beams 130, 140 is vertical motion in a direction perpendicular to the large surface area of ​​the beams.

[0058] The second assembly 200 includes a second traction cable 210, a second main weight 220, a third beam 230, a fourth beam 240, a third secondary weight 250 and a fourth secondary weight 260. The second traction cable 210 is connected to the second side of the clamping assembly at its proximal end 210p. The local coordinate origins M2, B3 and B4 are similar to the corresponding local coordinate origins M1, B1 and B2 discussed above. As described above, the second assembly 200 is identical in construction to the first assembly 100, but the dimensions of its components are different from those of the first assembly 100. More specifically, each load-bearing cable 110, 210 and beam 130, 140, 230, 240 has a unique length, and each main counterweight 120, 220 and secondary counterweight 150, 160, 250, 260 has a unique mass.

[0059] In an exemplary embodiment of the asymmetric Stockbridge damper with multiple resonant frequencies, the first and second traction cables 110, 210 are made of AISI316 stainless steel, tempered at 723 degrees Celsius. In the exemplary embodiment, the first traction cable 110 is 156 mm long and the second traction cable 210 is 206 mm long. In this example, all weights and beams are made of AISI4130 carbon steel, annealed at 865 degrees Celsius. In this example, the first main weight 120 is 76 mm wide, 52.25 mm long, 28.50 mm deep, and has a mass of 0.7425 kg. In this example, the second main weight 220 is 76 mm wide, 60 mm long, 30 mm deep, and has a mass of 0.5257 kg. In this example, the length of the first beam 130 is 71.90 mm, the length of the second beam 140 is 71.06 mm, the length of the third beam 230 is 72.99 mm, and the length of the fourth beam 240 is 74.94 mm. Also in this example, the radius of the first secondary weight 150 is 21.85 mm, the mass is 0.4500 kg, the radius of the second secondary weight 160 is 14.25 mm, the mass is 0.1600 kg, the radius of the third secondary weight 250 is 24 mm, the mass is 0.3500 kg, and the radius of the fourth secondary weight 260 is 15 mm, the mass is 0.1100 kg.

[0060] In this alternative embodiment of the asymmetric Stockbridge damper with multiple resonant frequencies, the first and second load cables 110, 210 may be provided by a single cable extending through the base of the clamp assembly 300. In such an embodiment, the first and second load cables 110, 210 would be segments of a single continuous cable, and the proximal ends of the load cables 110, 210 would be portions of the respective cable segments received in the base of the clamp assembly 300. The term "load cables" is intended to broadly encompass both configurations (separate first and second load cables and a single continuous cable in which the first and second load cables are segments of a single cable).

[0061] Each of the first and second components 100, 200 can be modeled as a three-beam three-mass system. The modeling theory will now be discussed. Referring to the first component 100, the first beam mass system includes the first load-bearing cable 110 and the first main weight 120, which has a coordinate system centered on M1 (the clamp assembly 300 and the proximal end 110p of the first load-bearing cable 110), as described above. The second beam mass system is the first beam 130 and the first secondary counterweight 150, which has a coordinate system centered on B1. The third beam mass system is the second beam 140 and the second secondary weight 160, which has a coordinate system centered on B2. In this model, the second and third beam mass systems are located on both sides of the first beam mass system. The first main weight 120 is considered to have rotation, while the first and second secondary weights 150, 160 are considered to be point masses.

[0062] The asymmetric Stockbridge damper 10 with multiple resonant frequencies provides ten mode shapes corresponding to ten natural or resonant frequencies. The mode shapes include up-and-down oscillations of the various components (i.e., periodic x' bending about the local x-axis and generally along the local y-axis). For convenience, such up-and-down oscillations may be referred to as vertical oscillations. Figures 4 to 8 Five mode shapes of the first assembly 100 are shown, and it will be appreciated that the second assembly 200 includes the same five mode shapes as the first assembly 100, bringing the total mode shapes of the damper 10 to ten.

[0063] Figure 4 A first assembly of an asymmetric Stockbridge damper having multiple resonant frequencies is shown in a first mode shape, wherein the first primary weight 120 is vibrating vertically at the end of the first load-bearing cable 110, while the first and second beams 130, 140 and the first and second secondary weights 150, 160 are maintained in their neutral positions. The neutral position of the components is essentially the stationary, unexcited state of the components. In the illustrated embodiment, the first mode shape occurs at 4.7767 Hz.

[0064] Figure 5 The second mode shape of the first assembly of an asymmetric Stockbridge damper with multiple resonant frequencies is shown, where the first secondary weight 150 vibrates vertically at the end of the first beam 130, while the first primary weight 120, the second beam 140 and the second secondary weight 160 remain neutral. In the embodiment shown, the second mode occurs at 12.758 Hz.

[0065] Figure 6The third mode shape of the first assembly of an asymmetric Stockbridge damper with multiple resonant frequencies is shown, where the second secondary weight 160 vibrates vertically at the end of the second beam 140 while the first primary weight 120, the first beam 130 and the first secondary weight 150 remain neutral. In the embodiment shown, the second mode occurs at 19.493 Hz.

[0066] Figure 7 The fourth mode shape of the first assembly of the asymmetric Stockbridge damper with multiple resonant frequencies is shown, where the first and second secondary weights 150, 160 vibrate vertically at the ends of the respective first and second beams 130, 140, while the first primary weight 120 remains neutral. The secondary weights 150, 160 in this mode are 180 degrees out of phase with each other, thereby producing a scissor kick motion, where one of the secondary weights 150, 160 moves upward while the other secondary weight 150, 160 moves downward, and vice versa. In the embodiment shown, the fourth mode occurs at 53.544 Hz.

[0067] Figure 8 The fifth mode shape of the first assembly of the asymmetric Stockbridge damper with multiple resonant frequencies is shown, where the first and second secondary weights 150, 160 vibrate vertically at the ends of the respective first and second beams 130, 140, while the first main weight 120 remains neutral. The secondary weights 150, 160 in this mode are in phase with each other, thereby producing a butterfly kicking motion, where the two secondary weights 150, 160 move upward together, and then the two secondary weights 150, 160 move downward together. In the embodiment shown, the fifth mode occurs at 144.86 Hz.

[0068] As described above, the second assembly 200 exhibits five modes that are essentially mirror images of the above-described first assembly 100. The additional five modes occur at frequencies of 3.2113 Hz, 9.9569 Hz, 15.793 Hz, 49.180 Hz, and 118.42 Hz.

[0069] Figures 9 to 11The clamp assembly 300 is shown in detail. The components of the illustrated embodiment of the clamp assembly 300 are a clamp body 310, a slider 320, and a crank assembly 330. The clamp body 310 is a unitary component having a base 340, a mid-body 345, a neck 350, and a head 355. The base 340 of the clamp body 310 includes a hole or load sling housing 360 that receives the proximal ends 110p, 210p of the first and second load sling cables 110, 210. As previously described, the load sling cables 110, 210 may include a segment of continuous cable extending through the load sling housing 360. The mid-body 345 is located above the base 340 and includes a pair of support arms 365, each having a mounting hole 370. The support arms 365 support the crank assembly 330, as previously described below. The neck 350 is located above the middle body 345 and includes a pair of rails 375 for capturing the slider 320 for linear sliding along the neck 350. The head 355 is hook-shaped and includes a curved surface 377 to receive and clamp the overhead power line 20. The curved surface 377 is in the shape shown or in other shapes suitable for the application and can be more generally referred to as a first clamping surface. A rubber boot 380 can be lined on the curved surface 377 of the clamp head 355 to improve the grip of the overhead power line 20.

[0070] Special References Fig. 9 , the slider 320 includes a relatively low friction base 385 and a rigid force transfer insert 395. The insert 395 has a draft angle and fits into a slot in the low friction base 385, which has a complementary draft angle to capture the insert 395. The guide 375 defines an undercut surface that captures the slider 320 and limits the movement of the slider 320 to linear movement toward and away from the clamp 355. The slider 320 includes a movable clamping portion 410 that defines a curved surface 415 for encircling the lower portion of the overhead transmission line 20. The curved surface 415 has the shape shown or other shapes suitable for the application and can be more generally referred to as a second clamping surface. The curved surface 415 can have a rubber lining 420 to improve grip.

[0071] The toggle crank assembly 330 includes a toggle crank 450 that is pivotally connected to the support arm 365 via a spring pin 455 that extends through the mounting hole 370. The spring pin 455 biases the toggle crank 450 toward the disengaged position ( Fig.10), in which position the toggle crank 450 allows the slider 320 to move away from the collet 355. The toggle crank assembly 330 includes a bolt 460 that extends through a slot 465 in the toggle crank 450 and a hole 470 in the collet 310. The bolt 460 and other suitable alternatives may be more generally referred to as an actuation mechanism. A nut 475 or other threaded socket is threaded onto the bolt 460 on the back of the clamp body 310. As an alternative to the nut 475, the hole 470 may be threaded. Rotation of the bolt 460 relative to the nut 475 in a first direction causes the bolt 460 to advance into the crank 450, which causes the crank 450 to pivot toward the clamp body 310 and toward the engaged position ( Fig.11 Rotation of the bolt 460 in a second direction opposite to the first direction causes the bolt 460 to retract from the crank 450, which allows the crank 450 to pivot (e.g., toward the disengaged position ( Fig.10 ).

[0072] The distal end of the crank 450 includes a cam surface 510 that engages with a ramp 515 at the lower end of the slider 320. Fig.10 ) pivots to the engaged position ( Fig.11 ), the cam surface 510 pivots and slides along the inclined surface 515. This causes the slider 320 to move from the disengaged position ( Fig.10 ) to the engaged position ( Fig.11 ). The slot 465 can accommodate the pivoting of the crank 450 relative to the bolt 460 so that the bolt 460 remains substantially horizontal throughout the range of motion of the crank 450. The crank 450 includes a curved surface surrounding the slot 465, and the bolt head engages the curved surface, thereby allowing the bolt head to abut against the crank 450 over a large range of angles when the crank 450 is moved to the engaged position. A lock washer or spring washer can be used between the bolt head and the curved surface to reduce the possibility of the bolt 460 loosening. When the crank 450 approaches the end of its engaged position, the engagement of the cam surface 510 with the inclined surface 515 produces a theoretically infinite force, which causes the curved surface 415 of the slider 320 and the curved surface 377 of the clamp 355 to produce a very high clamping force on the overhead power line 20.

[0073] Thus, the asymmetric Stockbridge damper provides a clamping assembly for attaching the damper to a pipeline and a wind vibration damper having at least six resonant frequencies.

[0074] Finally, all the parts of the invention not fully described adopt mature products and mature technical means in the existing technology.

[0075] In the description of this specification, reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in the embodiment or example of the invention.

[0076] Although embodiments of the invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. An asymmetric Stockbridge damper with multiple resonant frequencies, characterized in that: It includes a clamping assembly and two sets of counterweight assemblies, each set of counterweight assemblies includes a U-shaped weight block and a load-bearing cable, the distal end of the load-bearing cable is fixedly connected to the middle section of the opening side of the weight block; the top of the clamping assembly is buckled and hung on the overhead transmission line, wherein the top of the clamping assembly is buckled and hung on the overhead transmission line, and the bottom of the clamping assembly is fixedly connected to the proximal ends of the load-bearing cables of the two sets of counterweight assemblies.

2. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 1, characterized in that: The counterweight assembly comprises a first assembly and a second assembly, wherein: The first component includes a first main counterweight, a first beam and a second beam are respectively fixedly provided at both ends of a side wall of the first main counterweight, wherein the distal end of the first beam is fixedly connected to a first secondary counterweight, and the distal end of the second beam is fixedly connected to a second secondary counterweight; The second component includes a second main counterweight, and a third beam and a fourth beam are respectively fixedly provided at both ends of a side wall of the second main counterweight, wherein the distal end of the third beam is fixedly connected to a third secondary counterweight, and the distal end of the fourth beam is fixedly connected to a fourth secondary counterweight.

3. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 2, characterized in that: The volume and weight relationship of the first-level counterweight, the second-level counterweight, the third-level counterweight and the fourth-level counterweight is as follows: the first-level counterweight> the third-level counterweight> the second-level counterweight> the fourth-level counterweight.

4. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 1, characterized in that: The middle parts of the opposite side walls of the first main counterweight and the second main counterweight are provided with receiving holes for fixing and inserting load-bearing cables.

5. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 4, characterized in that: The load-bearing cables include a first load-bearing cable and a second load-bearing cable; The proximal end of the first load-bearing cable is covered and fixed by the bottom end of the clamping assembly, and the distal end of the first load-bearing cable is fixedly connected to the receiving hole of the first main counterweight block; The proximal end of the second load-bearing cable is covered and fixed by the bottom end of the clamping assembly, and the distal end of the second load-bearing cable is fixedly connected to the inside of the receiving hole of the second main counterweight block.

6. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 1, characterized in that: The lower part of the clamping assembly is a base serving as the main body of the clamping assembly, and a load-bearing sling shell covering and fixing the load-bearing cables at both ends is integrally fixed to the lower part of the base, and a middle body is integrally fixed to the upper part of the base; symmetrically arranged support arms are integrally formed on the side wall of the middle body, transversely penetrating bolt holes are provided on the middle body, and an inclined bent neck is integrally formed on the top of the middle body; symmetrically arranged guide rails are integrally formed on the side wall of the neck, and a downwardly bent chuck is integrally fixed to the top of the neck; a curved surface is provided on the bottom surface of the chuck, and a rubber sleeve is compositely bonded to the curved surface.

7. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 6, characterized in that: A toggle crank is rotatably sleeved on the spring pin, the top end of the toggle crank is integrally formed with an arc-shaped cam surface, and a through hole with a hole diameter larger than the bolt hole is opened on the toggle crank; a bolt is penetrated and connected in the through hole, the middle section of the bolt penetrates the bolt hole on the middle body, and the threaded end of the bolt is engaged and sleeved with a nut for adjusting the distance between the middle body and the toggle crank.

8. The asymmetric Stockbridge damper with multiple resonance frequencies according to claim 7, characterized in that: A slider is inserted into the guide rail in a sliding and guiding manner in the extending direction of the neck. The bottom surface of the slider is made into an inclined surface that slides with the cam surface of the elbow crank. A movable clamping part that cooperates with the clamp to clamp the overhead transmission line is integrally formed on one side of the upper part of the slider; the top surface of the movable clamping part is made into a curved surface, and a rubber lining is compositely bonded to the curved surface.

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