Clamp for fastening to a cable of an overhead line, and bird-protection fitting

Abstract

The clamp (2) is used for fastening to a cable (8) of an overhead line, in particular for a bird-protection fitting (1), wherein the clamp (2) extends along a centre axis (16) in a longitudinal direction (4) and has a clamping part (12) for fastening to the cable (8) and has a fastening part (14) for fastening at least one fitting part, wherein the fastening part (14) is mounted pivotably about the centre axis (16) on the clamping part (12) via a bearing, in particular a sliding bearing.

Description

[0001] Description

[0002] Clamp for attaching to a cable of an overhead line and bird protection fitting

[0003] The invention relates to a clamp for fastening to a cable of an overhead line and to a bird protection fitting.

[0004] An overhead line cable is generally understood to be a cable that is stretched outdoors at a height of several meters, usually several tens of meters or more. An overhead line is specifically understood to be a high-voltage line in which a large number of cables are guyed between two pylons to transmit power. The pylons are typically spaced several hundred meters apart. The high-voltage lines are usually designed for voltage transmission in the range of several hundred kV. The cables can be either phase conductors (conductor cables) or other guyed cables, such as ground wires or data cables, etc.

[0005] Such ropes, which are guyed outdoors at a certain height, often have signal elements attached for bird protection purposes, i.e. to draw birds' attention to the obstacle.

[0006] DE 10 2014 202 003 A1 discloses such a signaling arrangement, which is referred to below as a bird protection device. In this arrangement, several signaling elements designed as luminous elements are arranged on two spaced-apart clamps on a connecting mounting rod. These signaling elements are strip-shaped and are suspended and pivotably attached to the mounting rod. Based on this, the invention is based on the object of enabling a permanently reliable attachment of a device, in particular a bird protection device, to a cable of an overhead line.

[0007] The object is achieved according to the invention by a clamp for fastening to a cable of an overhead line, in particular for a bird protection fitting, wherein the clamp extends along a central axis in a (cable) longitudinal direction and comprises a clamping part for fastening to the cable and a fastening part for fastening at least one fitting part. The fitting part is, in particular, at least one signaling element for bird protection. The fastening part is mounted on the clamping part via a bearing in such a way that the fastening part is pivotally mounted about the clamping part and about the central axis.

[0008] The clamping part attached to the rope forms an inner part, which is surrounded on the circumference by the fastening part, which thus forms an outer part.

[0009] The term “surrounded on the circumference” is understood in particular to mean that the fastening part surrounds the clamping part in a shell-like manner.

[0010] The fastening part encompasses the clamping part over at least a certain angular range, which is typically over 180° and more preferably over 270°.

[0011] Both parts therefore enclose a clamping space for the rope, at least in part, or enclose the rope when clamped. The central axis runs through this clamping space. The central axis preferably runs inside the rope when the rope is installed.

[0012] During operation with the clamp mounted, i.e., when the clamp is clamped to the rope, the fastening part (and thus the bird protection device attached to it) can pivot around the inner clamping part clamped to the rope and around the central axis. The two parts are arranged concentrically with respect to the central axis and are designed, for example, like two nested sleeves. When viewed longitudinally, they typically each have circular arc-shaped sections, the center of which forms the central axis.

[0013] The clamping part and in particular also the fastening part are preferably open in the radial direction, i.e. perpendicular to the longitudinal direction, so that the rope can be inserted laterally into the clamping part and thus in particular also into the clamping space for assembly.

[0014] This design is based on the observation that with the conventional rigid fastening of such bird protection devices, the overhead line cable is subjected to stress in the area of ​​the respective clamp, which can lead to damage to the cable over the course of a typically several years of service. Due to the typically suspended arrangement of the bird protection devices, external loads, such as wind loads, result in (torsional) stress, which leads to increased stress on the cable in the area of ​​the clamp.

[0015] The pivoting mounting of the fastening part on the clamping part, which is rigidly and securely connected to the rope, enables a rotational movement of the fastening part relative to the clamping part around the central axis and thus around the (rope) longitudinal direction, and thus around the rope when the clamp is installed. This reduces the (torsional) load and prevents the risk of damage to the rope.

[0016] According to a preferred embodiment, the bearing is a plain bearing. This type of bearing is particularly robust and also comparatively easy to install. Furthermore, a plain bearing has a simple design, which keeps costs low. Conveniently, at least one plain bearing element is arranged between the clamping part and the fastening part. This at least one plain bearing element enables the pivoting movement with low or even defined friction.

[0017] In a preferred embodiment, the clamp, particularly the fastening part—viewed from the side—is hook-shaped, allowing the clamp to be hooked onto the rope. When installed, the clamp is simply hooked onto the rope and is preferably secured to it only via an easily attached spiral-shaped fastening rod. Such a clamp is particularly easy to install, especially compared to clamps where several shell-shaped parts must be screwed together on the rope.

[0018] In a preferred embodiment, the clamping part is designed as a hollow body having a cavity and a recess through which the clamping part is suspended from the cable. The clamping part has a partially cylindrical outer region with an outer bearing surface. The fastening part correspondingly has a partially cylindrical inner region with an inner bearing surface that concentrically surrounds the outer bearing surface of the clamping part.

[0019] In the plain bearing design, the bearing surfaces primarily form sliding surfaces. In other designs, rolling elements or other bearing bodies are arranged between the bearing surfaces. Where reference is made to partially cylindrical bearings in this case, this means that the respective bearing surface extends only over a limited angular range and not over its entire circumference. Viewed in cross-section, these partially cylindrical bearing surfaces each have a roughly C-shaped configuration.

[0020] The recess allows for easy attachment or removal of the clamp from the rope. The hollow space also allows for the insertion of one or more spiral-shaped fastening rods, referred to below as fastening spirals, to secure the clamping element.

[0021] To ensure the most cost-effective and simple design possible, the clamping part and / or the fastening part are each formed as an extruded profile. The extruded profile therefore extends longitudinally. An extruded profile means that the cross-sectional contour of the respective part is constant over its entire longitudinal extension. In particular, after cutting to length from a continuous extruded profile, no further post-processing steps are required.

[0022] To form the plain bearing, and specifically the plain bearing element, at least one bearing bush is arranged between the clamping part and the fastening part in a preferred embodiment. Therefore, a bearing gap is generally formed between the two parts, into which the bearing bush extends in the longitudinal direction. The bearing bush is typically made of a different material than the clamping part and fastening part in order to achieve good sliding properties. The bearing bush can be made of plastic, for example, whereas the clamping part and fastening part are made of metal, such as aluminum.

[0023] In a preferred embodiment, the bearing bushing is C-shaped in cross-section. It is therefore not completely closed around its circumference. This design enables the hook-shaped clamp and thus its suspended arrangement on the rope.

[0024] The bearing bush typically extends circumferentially over a suitable, limited angular range of less than 360°, for example, over an angular range between 240° and 320°, and in particular over an angular range between 270° and 300°. Corresponding to the clamping part's approximately C-shaped cross-section, the bearing bush also has partially cylindrical sliding surfaces (inner and outer) with a C-shaped cross-section, with which it rests against the corresponding sliding surfaces of the clamping part and the fastening part.

[0025] The bearing bush preferably has a mounting flange by means of which it is attached to one of the parts selected from the clamping part and the fastening part. Specifically, the bearing bush is attached to the outer fastening part. The attachment is preferably achieved by means of a screw fastening. For this purpose, corresponding through holes or screw holes are formed on the respective part, particularly on the fastening part.

[0026] In a preferred embodiment, the bearing bush is generally formed by a longitudinally extending, partially cylindrical bushing part and the fastening flange adjoining it on one side, which thus protrudes radially beyond the partially cylindrical bushing part. The fastening flange preferably protrudes both radially inward and radially outward beyond the bushing part. This creates a type of cap, which in turn is approximately C-shaped and defines a frontal cover. Among other things, this at least largely prevents the penetration of dirt into the plain bearing area.

[0027] Preferably, two bearing bushes are provided, each having a mounting flange at the end and a bushing part. These two bearing bushes are inserted from opposite sides into the bearing gap between the clamping part and the fastening part. This measure essentially covers the bearing gap from the two opposite sides. At the same time, it provides axial locking, so that the parts (fastening part, clamping part), which are particularly designed as profiles, are securely held.

[0028] The object is further achieved according to the invention by a bird protection device intended for attachment to a cable of an overhead line and comprising at least one clamp as described above. At least one signaling element is attached to this clamp, specifically to the fastening part. The preferred embodiments previously mentioned with regard to the clamp are therefore also applicable to this bird protection device with the at least one clamp.

[0029] Specifically, this bird protection fitting features the previously described hook-shaped clamp with the clamping part and the fastening part, wherein the clamping part is designed as a hollow body with the cavity and the indentation. In the assembled state, the clamp is suspended from the cable by means of the indentation. Furthermore, in the assembled state, at least one spiral fastening rod is guided through the cavity, via which the clamping part is held stationary on the cable. Furthermore, the bearing bush, which is C-shaped in cross-section, is arranged between the clamping part and the fastening part, forming a sliding bearing and allowing the fastening part to pivot about the center axis relative to the clamping part.

[0030] In particular, the bird protection device comprises two clamps spaced apart in the longitudinal direction, between which a mounting rod is held, from which several elongated signal elements are suspended and pivotable about a rod axis. The signal elements are specifically designed as slats or strips. Furthermore, they preferably exhibit a high contrast with one another, for example, a high light-dark contrast. Specifically, light signal elements are arranged alternating with dark signal elements.

[0031] An embodiment of the invention is explained in more detail below with reference to the figures. These show:

[0032] FIG 1 A a view of a bird protection device with several signal elements,

[0033] FIG 1 B is a side view of the bird protection fitting according to FIG 1 A,

[0034] FIG 2A a side view of a terminal,

[0035] FIG 2B is a sectional view through the clamp according to FIG 2A,

[0036] FIG 3A is a perspective view of a bearing bush, FIG 3B is a plan view of the bearing bush according to FIG 3A,

[0037] FIG 4 - 9 Side views of the clamp with different plain bearing variants, as well as

[0038] FIG 10 a partial view of the bird protection fitting with a locking element designed as a nut.

[0039] In the figures, parts with the same function are shown with the same reference symbols.

[0040] A bird protection device 1 shown in FIGS. 1A, 1B has, in the exemplary embodiment, two clamps 2 that are spaced apart from one another in a (cable) longitudinal direction 4. The clamps 2 are attached to a cable 8 via a fastening spiral 10. The clamps 2 hold a fastening rod 5, on which several strip- or lamellar-shaped signal elements 6 are arranged in a row in the longitudinal direction 4. The fastening rod 5 is designed in particular as a solid rod or alternatively as a cable or as a hollow rod. The signal elements 6 are usually made of plastic.

[0041] In addition to the double suspension with two clamps 2 shown, variants with only a single suspension via only one clamp 2, in particular attached centrally to the fastening rod 5, or also further multiple suspensions with more than two clamps 2 are provided.

[0042] The structure of the clamps 2 can be seen in particular from FIGS. 2A and 2B. Each clamp 2 is generally approximately hook-shaped so that it can be easily hooked onto a cable 8 of an overhead line. It is fastened to the cable 8 using a fastening spiral 10. This is usually formed from several directly adjacent spiral rods that form a group that is spirally guided around the cable 8. Typically, only one group or one spiral rod is provided, so that - viewed in cross-section - only a (small) part of the circumference is covered by the fastening spiral 10. Each clamp 2 has an inner clamping part 12 and an outer fastening part 14, which is arranged around the clamping part 12 so as to be pivotable about a central axis 16 (cf. FIG. 2B) and thus encompasses a circumferential section of the latter.A bearing gap is formed between the two parts 12, 14, into which a bushing part 18 of a bearing bush 20 extends. The structure of the bearing bush 20 is shown in particular in FIGS. 3A, 3B, from which it can be seen that a fastening flange 22 is connected to the end of the bushing part 18.

[0043] The clamping part 12 and the fastening part 14 are each designed as an extruded profile.

[0044] The clamping part 12 is designed as a hollow body, which—viewed in cross-section—has a C-shaped and thus partially cylindrical outer wall, forming a sliding surface. Furthermore, the clamping part 12 has an inwardly tapered wall region, forming a recess 24, with which the clamping part 12 can be suspended from the cable 8.

[0045] The two wall areas enclose a cavity 26 between them, which is in particular approximately crescent-shaped or partially annular. The fastening spiral 10 is guided through this cavity.

[0046] The fastening part 14 is, viewed in cross-section, hook-shaped overall and has an upper, again approximately C-shaped section, to which a vertical section adjoins downwards. In the exemplary embodiment, this section has a bearing eye at its end, which is provided for attaching the aforementioned fastening rod, on which the individual signal elements 6 are arranged suspended and pivotably.

[0047] The C-shaped portion has an inwardly oriented and partially cylindrical inner sliding surface, which is configured to correspond to the outer sliding surface of the clamping part 12. The sliding surfaces are arranged concentrically to one another. Furthermore, it can be seen that circular passages are formed on the outer circumference of the C-shaped portion, through which bolt-shaped fastening elements, in particular screws 28, are guided in the assembled final position.

[0048] At least one bearing bush 20, as specifically illustrated in Figures 3A and 3B, is arranged between the clamping part 12 and the fastening part 14. In the exemplary embodiment, two such bearing bushes 20, which are preferably designed as identical parts, are inserted from opposite sides into the bearing gap between the two parts 12 and 14.

[0049] Each bearing bush 20 has the aforementioned bushing part 18, which, viewed from the side, is only approximately C-shaped and thus has an opening area along its circumference. The bushing part 18 is therefore partially cylindrical. The fastening flange 22 adjoins the end. This preferably extends over the bushing part 18 both radially inward and radially outward. This covers the C-shaped bearing area like a cap and thus protects it from the ingress of dirt.

[0050] On the fastening flange 22, through-openings 30 are formed—similar to and corresponding to the through-openings on the fastening part 14—through which the fastening elements, in particular screws 28, can be inserted. In the exemplary embodiment, three such through-openings 30 are arranged distributed around the circumference.

[0051] To assemble the respective clamp 2, the two parts 12, 14 are pushed into one another, and a bearing bush 20 is inserted from each side into the bearing gap between these two parts 12, 14. The fastening bolts (screws 28) are then passed through the through-openings 30 and the longitudinal passages 4, so that the bearing bushes 20 are fastened to the other two parts 12, 14. The invention has been described here with reference to the exemplary embodiment illustrated in the figures, but is not limited thereto. For example, it is possible to provide other plain bearing elements in the bearing gap between the two parts 12, 14 as an alternative to the bearing bush 20 shown.For example, it is possible to provide individual rod-shaped sliding elements distributed around the circumference and extending in the longitudinal direction, which are preferably held in a form-fitting manner in recesses either in the fastening part 14 or in the clamping part 12. The sliding elements can also be spring elements distributed around the circumference, which thus also keep the two parts 12, 16 spaced apart from each other by spring force.

[0052] FIGS. 4 to 9 show different variants of plain bearings. These generally feature a number (one or more) of spring elements 32, which perform a dual function: first, they exert a radial spring force and thus, in particular, exert a centering effect on the clamping part 12, and second, they form a number of plain bearing surfaces.

[0053] The spring elements 32 are optionally attached to the clamping part 12 or to the fastening part 14. In the variants of FIGS. 4 to 7, several individual receptacles 34 distributed around the circumference, particularly in the outer fastening part 14, are formed, in which the spring elements 32 are held. For example, they are resiliently spread in these receptacles 34. The receptacles 34 are preferably approximately circular in cross-section and open toward the clamping part 12. Specifically, they are designed as (profile) channels elongated in the axial direction.

[0054] The spring elements 32 are preferably also generally elongated in the longitudinal direction 4 and preferably extend over the entire length of the two parts 12, 14. In the embodiment of FIG. 4, a plurality of spring elements 32 designed in the manner of leaf springs are provided, which are each spread with their (bent) ends in a receptacle 34, in particular resiliently, and are held thereby.

[0055] In the variant according to FIGS. 5 to 7, exactly one spring element 32 is located in each of the receptacles 34. In FIGS. 5 and 7, this spring element is designed in the manner of a snap ring when viewed in cross-section. Specifically, the spring elements 32 are designed as slotted sleeves made of a suitable spring material (FIG. 5B). They can be oval (FIG. 5A) or circular (FIG. 7) in cross-section.

[0056] In the variant according to FIGS. 6A, 6B, the spring element 32 has resilient side arms on both sides of a central region with which it lies in the receptacle 34, which side arms are designed in particular as a corrugated profile.

[0057] Finally, in the variants shown in FIGS. 8 and 9, a spring element 32 with a partially circular cross-section is provided, which has radially projecting bulges. These are formed, for example, by a corrugated profile (FIG. 8) or by pressed-out nubs (FIG. 9) or even punched-out spring tabs.

[0058] FIG. 10 shows a section of the bird protection device 1, in which a securing element is attached to the end of the fastening rod 5, which serves to axially secure the individual signal elements 6. In the exemplary embodiment, this is designed as a conventional nut 36, which is connected to the fastening rod by pressing. The fastening rod 5 is preferably designed without a thread, whereas the nut 36 has an internal thread.

[0059] By pressing, material from the fastening rod 5 is pressed into the internal thread, thereby forming the press connection. The nut 36 is made of the same material as the fastening rod 5, in particular aluminum. Other securing elements are also possible; for example, the fastening rod 5 can be designed at the end like a (semi-circular) rivet, or a hollow rivet or even a blind rivet can be provided for securing.

[0060] List of reference symbols

[0061] 1 bird protection fitting

[0062] 2 terminal

[0063] 4 Longitudinal direction

[0064] 5 fixing rod

[0065] 6 Signal element

[0066] 8 rope

[0067] 10 fastening spiral

[0068] 12 clamping part

[0069] 14 Fastening part

[0070] 16 Center axis

[0071] 18 Socket part

[0072] 20 bearing bush

[0073] 22 Mounting flange

[0074] 24 indentation

[0075] 26 cavity

[0076] 28 screws

[0077] 30 passage opening

[0078] 32 spring element

[0079] 34 recording

[0080] 36 mother

Claims

Claims 1. Clamp (2) for fastening to a cable (8) of an overhead line, in particular for a bird protection fitting (1), which extends along a central axis (16) in a longitudinal direction (4) and has a clamping part (12) for fastening to the cable (8) and a fastening part (14) for fastening at least one fitting part, wherein the clamping part (12) is an inner part which is circumferentially surrounded by the fastening part (14) and wherein the fastening part (14) is pivotably mounted about the central axis (16) via a bearing on and around the clamping part (12).

2. Clamp (2) according to the preceding claim, wherein the bearing is a plain bearing.

3. Clamp (2) according to the preceding claim, wherein at least one sliding bearing element is arranged between the clamping part (12) and the fastening part (14).

4. Clamp (2) according to one of the preceding claims, wherein the clamp (2), in particular the fastening part (14) - viewed in a side view - is designed in a hook shape so that it can be hooked onto the rope (8).

5. Clamp (2) according to one of the preceding claims, wherein the clamping part (12) is designed as a hollow body with a cavity (26) and a recess (24) for attaching to the rope (8), wherein at least one fastening spiral (10) for attaching to the rope (8) can be passed through the cavity (26).

6. Clamp (2) according to one of the preceding claims, wherein the clamping part (12) and / or the fastening part (14) is designed as an extruded profile.

7. Clamp (2) according to claim 3, wherein a bearing bushing (20) is arranged as a sliding bearing element between the clamping part (12) and the fastening part (14).

8. Clamp (2) according to the preceding claim, wherein the bearing bushing (20) is C-shaped in cross-section.

9. Clamp (2) according to one of the two preceding claims, wherein the bearing bushing (20) has a mounting flange (22) by means of which it is attached to one of the parts selected from the clamping part (12) and the mounting part (14), in particular screwed on.

10. Clamp (2) according to one of claims 7 to 9, wherein the bearing bushing (20) has a bushing part (18) extending in the longitudinal direction (4) and a mounting flange (22) adjoining it, wherein the bushing part (18) is arranged between the clamping part (12) and the mounting part (14) and the mounting flange (22) projects perpendicularly to the longitudinal direction (4) on both sides beyond the bushing part (18) and thereby partially covers an end face in the manner of a cap.

11. Clamp (2) according to one of claims 7 to 10, wherein two bearing bushes (20) are provided, each having an end-side mounting flange (22) and being inserted from opposite sides between the clamping part (12) and the mounting part (14).

12. Clamp (2) according to one of claims 3 to 11, in which at least one sliding bearing element provides a radially resilient bearing, by means of which in particular a centering of the clamping part (12) relative to the fastening part (14) is provided.

13. Clamp (2) according to the preceding claim, wherein one or more spring elements (32) are arranged between the clamping part (12) and the fastening part (14), which are optionally held on the clamping part (12) or the fastening part (14), wherein optionally - several individual spring elements (32) distributed around the circumference are provided, which are located in particular in recesses (34). - a ring segment - viewed in cross-section - with radial, for example The bird protection fitting (1) is provided with knob-shaped or wave-shaped protrusions as a spring element. It is a bird protection fitting (1) for attachment to a cable (8) of an overhead line, with at least one clamp (2) according to one of the preceding claims, to which at least one signaling element (6) is attached. It is a bird protection fitting (1) according to the preceding claim, wherein - the clamp (2) - viewed from the side - is hook-shaped and has a clamping part (12) and a fastening part (14), - the clamping part (12) is designed as a hollow body with a cavity (26) and a recess (24), and the clamp (2) is suspended with the recess on the rope (8), - a fastening spiral (10) is guided through the cavity (26) so that the clamping part (12) is attached to the rope (8), - a C-shaped bearing bushing (20) in cross-section is arranged between the clamping part (12) and the fastening part (14), such that a sliding bearing is formed and the fastening part (14) is pivotable about a central axis (16) with respect to the clamping part (12). Bird protection fitting (1) according to one of the two preceding claims, in which at least one clamp (2) or two clamps (2) spaced apart from each other in the longitudinal direction (4) are provided, on which a fastening rod (5) is held, on which several elongated, in particular lamellar, strip-like signal elements (6) are suspended and pivotable about a rod axis.Bird protection fitting (1 ) according to one of claims 14 to 16, wherein the clamp (2) holds a fastening rod (5) to which the at least one signal element (6) is attached, wherein a locking element for axially securing the signal element (6) is formed at the end of the fastening rod (5), which is designed as a nut (36) which is pressed onto the fastening rod (5).

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