RU2180765C1 - Vibration damper - Google Patents

Abstract

FIELD: power engineering; overhead power transmission and communication lines using self-carrying fiber-optic cables. SUBSTANCE: vibration damper has weights in the form of bodies of revolution of flexible damping member and clamp. Weights are press-fitted on ends of flexible member by means of cylindrical bushing which is then expanded in cylindrical through bore of weights. Chosen weights are unequal in mass; they are secured asymmetrically relative to vertical axis of clamp and at certain angle to longitudinal axis of flexible damping member. EFFECT: enhanced gain-frequency response and vibration damping capacity within wide range of resonant frequencies. 2 cl, 5 dwg

Description

 The invention relates to the field of electric power, and more particularly to vibration dampers for wires of overhead power lines and fiber optic cables of communication lines.

 Known vibration damper for the wires of an overhead power line, containing an elastic element made in the form of a steel rope, at the ends of which weights are fixed, in the form of a curved tube, and a clamp, one end fixed in the middle of the elastic element, and the other end on the line wire [1].

 This absorber has several disadvantages. The amplitude-vibrational characteristics of such a damper are not optimal and, to ensure their optimality, the tubes are filled with material with certain properties (bulk materials, liquid, etc.). To ensure good quenching properties of the absorber, the bulk material should be placed in the cargo tubes closer to the places of sealing the elastic element, so that the moments of inertia of the goods fall on the bend points of the tubes. This all complicates the design and makes labor-intensive manufacturing of absorbers of this type.

 Known vibration damper, the loads of which are in the form of a "dog bone" (dog bone), and the elastic element (steel rope) is fixed with an offset (eccentricity) relative to the axis of symmetry of the goods [2].

 This absorber has quite good damping characteristics when used on wires of power lines. However, it does not have a wide enough frequency range and cannot absorb the entire spectrum of vibrations that occur in fiber-optic cables of communication lines, which are more sensitive (damaged) to vibrations than wires of overhead power lines. In addition, the difference in the technology of securing the clamp and weights on the steel rope (pressing and pouring with molten metal, respectively) requires the use of various expensive technological equipment, which leads to an increase in the cost of the product.

 The closest technical solution to the claimed one is a vibration damper for wires of overhead power lines and self-supporting fiber-optic cables of communication lines, containing an elastic damper element made in the form of a set of spiral wires of high strength steel, fixed with its ends in the loads by crimping worn on it a cylindrical sleeve with a conical protrusion, and a clamp, one end fixed in the middle of the elastic damper element, and the other on the wire or cable e, wherein the loads are deployed at an angle in a vertical plane relative to a plane passing through the clamp [3].

 However, this vibration damper has a significant drawback, namely, a narrow range of frequencies at which the optimal damping ability of the oscillations is achieved, practically this damper operates in one rather limited frequency range, which dramatically reduces its use on overhead power lines and for self-supporting fiber optical cables of communication lines.

The authors set themselves the goal of creating a vibration damper for overhead power lines and self-supporting fiber-optic cables of communication lines, free from the disadvantages of known damper, a damper that provides high energy absorption during vibration over a wide range of vibration frequencies (the so-called multi-frequency vibration damper). The latter is achieved due to a combination of essential distinguishing features, namely, a vibration damper for overhead power line wires and self-supporting fiber-optic cable for communication lines, containing an elastic damper element made in the form of a set of spiral wires made of high-strength steel, fixed at its ends by means of crimping put on on it a cylindrical sleeve with a conical protrusion, and a clamp, one end fixed in the middle of the elastic damper element, and the other on a wire or cable, and the loads are turned at an angle in a vertical plane relative to the plane passing vertically through the clamp, while the said set of elastic damper element consists of 19 spiral wires in a strained stress state, achieved by twisting the spiral segments and then crimping them around the entire perimeter of the circumference of the element, the loads are made in the form of a body of revolution, are mounted on the elastic damper element asymmetrically with respect to the vertical axis of the clamp n distances from it, chosen from the ratio of L _1: L ₂ = 1.1-1.2, and are arranged so that their axes of symmetry have a slope to the longitudinal axis of the elastic damping element at an angle ψ between 15 ^o -25 ^o, with the masses of goods are not equal to each other and are found from the relation m ₁ : m ₂ = 1.2 -1.3, the cylindrical sleeve from one end is made with a wall thinning to 1.5 mm and a shoulder along its end, in the thickened part of the goods a through cylindrical hole was made with recesses with a diameter of not more than 20 mm from its two sides and longitudinal grooves, protecting conductive sleeve from rotating in loads, where L ₁ and L ₂ - distance of first and second loads from the points of fastening them on an elastic damping element to a vertical clamping axis, m ₁ and m ₂ - weight of the first and second loads respectively, ψ - axis tilt angle cargo; the clip can be made in the form of a hook, the curved part of which is fixed to the wire or cable using at least one piece of spiral wire that is elastically wound on the wire or cable symmetrically from both sides of the curved part of the hook.

 The invention is illustrated by drawings, where figure 1 shows a General view of a vibration damper, made according to the present invention, a front view in a direction perpendicular to the wire or cable line; figure 2 is the same as in figure 1, a top view; figure 3 is the same as in figure 1, a side view along the wire or cable line; figure 4 is the same as in figure 1, the drawing shows in a detailed section the structure of the fastening of the elastic damper element in the load; figure 5 - vibration damper, in which the clamp is made in the form of a hook according to claim 2.

The vibration damper for wires 1 of overhead power lines, as well as self-supporting fiber optic cables 1 of communication lines is a structure consisting of weights 2, an elastic damper element 3 and a clamp 4. Weights 2 made of cast iron, for example, made by casting, are made in the form of a body rotation, which has a thickened part (base) 5, a narrow part (neck) 6 and a head 7. In the thickened part 5 of each load 2, a through cylindrical hole 8 is drilled, on both sides of which a recess 9 with a diameter of not more than 20 mm and longitudinal grooves 10. Loads 2 are selected by mass not equal to each other, in particular their masses are in the following ratio m ₁ : m ₂ = 1.2-1.3, where m ₁ and m ₂ are the masses of the first and second cargo, respectively.

 The elastic damper element 3 (steel cable) is a set of spiral wires of high strength steel, which is fixed in one and the second load 2. The optimal number of spiral wires included in the set of element 3 is 19 pieces. The spiral wires are in a strained strain state, which is ensured by twisting the spiral segments with their further compression around the entire circumference of the element 3. The steel cable 3 is fastened in loads 2 in the thickened part (base) of the latter 5 using a cylindrical sleeve 11 having a conical protrusion 12 and bead 13 at its end 14.

 The clamp 4 consists of a housing 15 and the clamping device 16 itself, which are fastened to each other on the wire or cable 1 by means of a bolt 17 and a nut 18. To securely fix and create the necessary tightening force of the clamp 4 on the wire or cable 1, the bolt 17 is made with a reduced ( shallow) thread and plate washers 19. In addition, as an option, the clip can be made in the form of a hook 20. In this case, the hook 20 is worn on its wire or cable 1 with its curved part 21 and secured to it by a piece of 22 spiral wire rigidly wound around due to the elasticity of the spiral on both sides of the fixing point of the curved part 21 of the hook 20.

The location of the goods 2 on the elastic damper element 3 meets certain conditions that are optimally selected by calculation and experimental methods in order to ensure its maximum damping ability in a wide range of resonant vibration frequencies:
firstly, the loads 2 are fixed on the elastic damper element 3 at different distances (asymmetrically) from the vertical axis 23 of the clamp 4. These distances are selected from this ratio L ₁ : L ₂ = 1.1-1.2, and on the shoulder of a shorter length the load of less weight is fixed;
secondly, the loads 2 are in a deployed position in a vertical plane relative to another vertical plane passing through the clamp 4, at an angle φ = 30-60 ^° ;
thirdly, the loads 2 are arranged so that their axis of symmetry are inclined with respect to the longitudinal axis 24 of the elastic damper element 3 at an angle ψ = 15-25 ^° .
The vibration damper is assembled as follows.

 A cylindrical sleeve 11 is put on the elastic damper element 3 from both its ends and pressed into a hexagon in the middle of the generatrix of the cylinder 11 (crimping is done in one place in the middle of the sleeve 11 instead of the two previously provided). Then, weights 2 are mounted on the elastic damper element 3 with the bushings 11 through cylindrical through holes 9 and the bushings 11 are flared into their recesses 9 and into the grooves 10. Then, the elastic damper element 3 together with the weights 2 mounted on it are fixed using a clamp 4 or a hook 20 on a wire or cable of 1 line. The locations of vibration dampers on wires or cables of 1 lines are determined by mathematical modeling and based on the specific conditions of their work and the passage of lines in specific climatic zones.

 The inventive vibration damper has significant advantages compared to devices of a similar purpose in terms of higher amplitude-frequency characteristics, a much wider frequency range for damping vibrations of various types (from vibration to sub-vibrations), higher energy absorption during vibration, and also in terms of simplifying the design and quencher manufacturing techniques.

Sources of information
1. US patent 3400209, CL. 174-42, 09/03/1968.

 2. US patent 4159393, CL 174-42 (H 02 G 7/14), 06/26/1979.

 3. RF patent 2107373, cl. H 02 G 7/14, 12.24.1996.

Claims (2)

1. A vibration damper for overhead power lines wires and self-supporting fiber-optic cables of communication lines, comprising an elastic damper element made in the form of a set of spiral wires of high-strength steel, fixed with its ends in loads, by crimping a cylindrical sleeve worn on it with a conical protrusion, and a clamp, fixed at one end in the middle part of the elastic damper element, and the other on the wire or cable, and the loads are deployed at an angle in the vertical plane relative to but the plane passing vertically through the clamp, characterized in that the said set of elastic damper element consists of 19 spiral wires in a strained strain state, achieved by twisting the spiral segments and then crimping them around the entire circumference of the element’s circumference, the loads are made in the form rotation of the body, mounted on an elastic damping element asymmetrically about the vertical axis of the clip at a distance from it, chosen from the ratio L _1: L ₂ = 1.1-1.2, and the same are located way that their symmetry axis have a slope to the longitudinal axis of the elastic damping element at an angle ψ in the range 15-25 ^o, wherein the cargo weight not equal to each other and from the ratio of m _1: m ₂ = 1.2-1.3, a cylindrical sleeve from one end is made with a wall thinning to 1.5 mm and a shoulder along its end; in the thickened part of the cargo, a through cylindrical hole is made with recesses with a diameter of not more than 20 mm on both sides and longitudinal grooves that protect the bushings from rolling in loads where L ₁ and L ₂ - distance of first and second of the goods from their fixing points on the elastic damping element to the vertical axis of the clamp, m ₁ and m ₂ - weight of the first and second loads respectively, ψ - angle cargo axis.  2. The damper according to claim 1, characterized in that the clamp is made in the form of a hook, the curved part of which is fixed to the wire or cable using at least one piece of spiral wire elastically wound on the wire or cable symmetrically from both sides of the curved parts of the hook.

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