Wedge-type tension clamp and guying device having a wedge-type tension clamp of this kind

Abstract

The wedge-type tension clamp (4) for a cable (6) has two clamping wedges (12) extending in a longitudinal direction (L), wherein, in the assembled state, the clamping wedges (12) are accommodated in a clamping housing (10). The clamping wedges (12) have a channel (24) for clampingly receiving the cable (6), which channel extends in the longitudinal direction (L) and in which channel there is a groove (20) extending in the longitudinal direction (L). By means of the groove (20), the transverse compressive forces during tensioning are advantageously set such that the wedge-type tension clamp (4) is also suitable for cables (6) having a pressure-sensitive core.

Description

[0001] Description

[0002] Wedge clamp and guying device with such a wedge clamp

[0003] The invention relates to a wedge guy clamp and a guying device with such a wedge guy clamp.

[0004] Wedge clamps are used in guying devices for guying cables, particularly conductors on overhead power lines. The wedge clamp has two longitudinally extending clamping wedges housed in a clamping housing. When the cable is subjected to tensile stress, the wedge shape creates a self-clamping effect, reliably clamping the cable. The basic design of such wedge clamps can be found, for example, in EP 1 255 339 B1, DE 40 19 999 A1, and AT 224183 B.

[0005] Such wedge clamps achieve reliable clamping with high clamping force. The clamping wedges exert high transverse forces on the rope from two directions, typically resulting in deformation or ovalization of the rope being clamped.

[0006] However, such wedge clamps are not suitable for ropes with pressure-sensitive cores, where a central, high-tensile strand, for example made of carbon fibers and / or glass fibers, serves as the pressure-sensitive core. When using a conventional wedge clamp, there is a risk that the pressure-sensitive core will deform or be damaged under heterogeneous radial compressive stress (transverse force primarily from two directions from the two clamping wedges), and for example, axially tear or break. CN 201041930 Y also describes a clamp with a different clamping concept. It features a slotted clamp sleeve into which a fastening hook is screwed at the end, enabling axial displacement.In this design, the clamping force is exerted by elastic deformation of the individual sections of the slotted sleeve—unlike wedge clamps with two dimensionally stable clamping wedges. However, the manufacture and assembly of such a slotted sleeve is complex.

[0007] Based on this, the invention is based on the object of enabling reliable guying of a rope with a pressure-sensitive core at low cost and low installation effort.

[0008] The object is achieved according to the invention by a wedge guy clamp for a rope and by a guying device with such a rope. The wedge guy clamp has two clamping wedges extending in a longitudinal direction, each of which is a separate structural unit. The clamping wedges taper in a wedge shape in the longitudinal direction. When assembled, the two clamping wedges are accommodated in a clamping housing. The clamping housing has a receptacle for the clamping wedges, which is usually also wedge-shaped in the longitudinal direction. The clamping wedges also have a longitudinally extending groove in which the rope to be clamped lies when assembled. A longitudinally extending groove is now formed in this groove. In the guying device, the rope lies in this wedge guy clamp and is reliably clamped.

[0009] Of particular importance for the reliable and gentle clamping of a rope with a pressure-sensitive core is the additional groove incorporated into the channel. Studies have shown that the groove in the bottom of the channel has a beneficial effect on the radial clamping forces, particularly on the core, so that the (transverse) compressive stress on the pressure-sensitive core is significantly more homogenized radially than with a conventional wedge clamp without such a groove. This effect is sufficiently large to ensure that the pressure-sensitive core is not damaged while simultaneously providing reliable and secure clamping of the rope. By specifically designing the groove, the pressure zones on the rope and also on the core can be precisely adjusted.

[0010] To avoid potential pressure zones, the entire clamping area, and especially the grooves, are constructed homogeneously. This means that each groove has a consistently smooth surface over the entire length, at least of the clamping area. In particular, the grooves are free of radially protruding ribs, especially those running transversely to the longitudinal direction.

[0011] The two clamping wedges are generally two separate components, each with a groove and a slotted slot. These components exhibit sufficiently high inherent rigidity that, unlike a slotted sleeve, they remain dimensionally stable and do not deform elastically even when clamping the rope. Due to their wedge-shaped design, the two clamping wedges are only offset radially from each other to exert the clamping force.

[0012] Overall, this allows for the usual easy installation of the rope with a simple structure similar to conventional wedge clamps.

[0013] At the same time, the groove also allows for clamping of ropes with pressure-sensitive cores.

[0014] If reference is made here to a groove, this means a material recess extending in the longitudinal direction within a base body and in the wall of the clamping wedge, without this wall being penetrated. This means that each groove has a groove base which is formed by the base body of a respective clamping wedge. Each groove extends over the entire length of the clamping wedge, at least over the length of a clamping area. Each groove therefore runs freely at the opposite ends of the clamping area and in particular at opposite end faces of the clamping wedge. The clamping area is defined by the area in which, in the assembled state, the rope is clamped between the two clamping wedges and which therefore exert a clamping force on the rope.

[0015] The two clamping wedges have an identical design, at least in cross-section across the clamping area. Preferably, at least the contour directed toward the cable structure to be clamped, i.e., the contour that grips the cable, is identical.

[0016] Each clamping wedge is a one-piece, particularly monolithic component, at least in the area of ​​the conductor to be clamped. Each groove has a wall formed by the clamping wedge, which, viewed in cross-section, preferably runs along a circular arc with a predetermined clamping radius.

[0017] The groove therefore extends over the entire length of at least the clamping area, and furthermore, a profile cross-section formed by the groove and the groove—at least a cross-sectional contour facing the rope—is constant over the entire length of the clamping wedge or at least the clamping area. This means that the cross-sectional contour of the groove and the cross-sectional contour of the groove, i.e., their course on the side facing the rope (curvature, width of the groove, depth of the groove), are consistent over the entire length. This ensures a homogeneous, uniform compressive load across the entire clamping area, and undesirable local pressure zones or pressure peaks are avoided.

[0018] In a preferred embodiment, the clamping radius corresponds to the outer radius of the rope structure of the rope to be clamped. A clamping diameter (twice the clamping radius) typically ranges from 10 mm to 60 mm. Depending on the design, the outer radius of the rope structure is defined, for example, by the rope itself or, for example, by the rope plus a protective spiral surrounding it. This also promotes a homogeneous pressure distribution and avoids local pressure zones or pressure peaks.

[0019] The groove has a radial depth that is one gap smaller than the clamping radius. Therefore, when the two clamping wedges are in contact with the rope structure, the two clamping wedges are spaced apart by twice the gap.

[0020] The groove itself is defined by the groove base and two opposing groove walls. Each groove has a groove depth and a groove width. The groove depth is always less than the wall thickness of the clamping wedges, and in particular less than half, and preferably less than, the wall thickness of the clamping wedge, based on its thickest section.

[0021] The groove depth is defined as the radial / vertical distance between the circular arc running along the wall of the channel and the groove base. The groove width is defined as the distance between the two groove walls perpendicular to a radial / vertical direction, at half the height of the groove depth.

[0022] According to a preferred embodiment, the groove width is in the range between 0.5 times and five times the gap between the mounted clamping wedges and in particular in the range between one and three times the gap, especially twice the gap.

[0023] Furthermore, the groove depth is preferably in the range between 0.5 and 1.5 times the groove width, and in particular in the range up to a maximum of one times the groove width. The groove depth is preferably approximately two-thirds of the groove width.

[0024] In a preferred embodiment, the groove depth is smaller than the groove width. Studies have shown that such dimensions are particularly suitable for the desired distribution of transverse compressive forces, reliably protecting the pressure-sensitive core.

[0025] Preferably, the groove transitions into the wall of the channel in a rounded manner. The groove walls therefore have a transition radius that merges into the clamping radius. This avoids a sharp-edged transition.

[0026] The cross-sectional contour of the groove is preferably approximately rectangular; alternatively, it can also be circular or polygonal, e.g., triangular. A sufficient groove width and, preferably, a rounded transition into the wall are important.

[0027] In addition, a rounded transition is preferably also formed between the groove base and the groove walls. The transitions from the groove base to the groove walls on the one hand, and from the groove walls to the wall of the channel on the other hand, for example, have the same radius. The groove walls - viewed in cross-section - preferably run continuously curved along arcuate lines, thus, for example, in an S-shape from the groove base to the wall. The groove base preferably runs in a straight line.

[0028] Preferably, the groove width widens from the groove base toward the channel. Therefore, the lateral groove walls are preferably inclined. The two groove walls therefore do not run parallel to each other and enclose a groove angle between them. This angle is preferably in a range between 30° and 50°, and in particular approximately 40°. This measure achieves a smooth and even transition into the channel wall and thus a suitable transverse compressive load.

[0029] The rope held by the guying device is, in particular, a rope with a pressure-sensitive core, in particular a carbon core or a glass fiber core. This means that the core preferably consists of a plurality of individual non-metallic fibers, in particular carbon fibers and / or glass fibers. These are typically embedded in a matrix. This core forms a central, high-tensile strand. Typically, several layers of rope strands are arranged around this core. These rope strands are typically made of aluminum.

[0030] In a preferred embodiment, a protective spiral is also attached around the rope. This preferably extends only in the area of ​​the wedge guy clamp, i.e. has a length that is, for example, between twice or even three times the length of the wedge guy clamp. However, the protective spiral extends at least over both ends of the clamping wedges, preferably over the length of the clamping area (length of the clamping wedges). A curved rope guide, also referred to as a run-out, is typically attached to one of the two clamping wedges. The protective spiral preferably extends at least over this rope guide. The protective spiral consists of at least one, and if necessary, several, rods wound spirally around the rope. These rods are preferably made of aluminum. The rope, together with the protective spiral, forms the rope structure to be clamped.For versions without a protective spiral, the rope diameter and thus the clamping diameter of the clamping wedges is typically in the range of 10 mm to 50 mm, and for versions with a protective spiral, the corresponding diameter is typically in the range of 15 mm to 60 mm.

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

[0032] FIG 1 is a side view in the form of a longitudinal section of a guying device with a wedge guying clamp and a rope with a pressure-sensitive core held therein,

[0033] FIG 2 a plan view of a clamping wedge,

[0034] FIG 3 is a front view of the clamping wedge shown in FIG 2 and FIG 4 is an enlarged view of the area marked with a circle in FIG 3.

[0035] A guying device 2 shown in FIG. 1 comprises a wedge guying clamp 4 with a cable 6 clamped therein. The cable 6 has a pressure-sensitive core 8, which is formed, for example, as a carbon core. Several metallic cable strands are arranged around this core, stranded in one or more layers.

[0036] The wedge guy clamp 4 extends in a longitudinal direction L and has a clamping housing 10 in which two clamping wedges 12 are accommodated. The wedge guy clamp 4 is usually made of metal, for example aluminum. The basic structure of such wedge guy clamps 4 is known. For example, the clamping housing 10 has two side parts and a housing base, so that it is U-shaped in cross-section and the cable 6 can be inserted laterally. After the cable 6 has been inserted, the clamping housing 10 is closed by a housing cover. The housing cover and housing base are designed in particular like profile rails that can be inserted longitudinally into a corresponding profile structure of the side parts. The clamping housing 10 defines a free interior space that tapers in a wedge shape in the longitudinal direction. This is achieved in particular by a wedge-shaped design of the profile rails.

[0037] As can be seen particularly from FIG. 1, the two clamping wedges 12 are wedge-shaped when viewed from the side. The vertically opposite outer sides of each clamping wedge 12 rise in a wedge shape at a wedge angle a and rest against a corresponding, inclined wall of the terminal housing 10. This wall is formed by the profile rails.

[0038] The two clamping wedges 12 define a clamping area 13, within which they exert a radial clamping force on the cable 6. The clamping area extends over the entire length of the clamping wedges 12. On one of the two clamping wedges 12, in the exemplary embodiment on the clamping wedge 12 shown in the lower half of the image, a curved cable guide 14 is usually attached, which together with the clamping wedge 12 can form a (monolithic) component. In the present case, the clamping wedge 12 is understood to mean (only) the wedge-shaped area in which the opposite outer sides run at the wedge angle α to each other. The two clamping wedges 12 are connected to one another at the rear edge of the clamping area 13. For this purpose, each clamping wedge 12 has widened portions 16 with through holes, so that a type of clamp is formed. At the end of the curved rope guide 14, another screw clamp 18 is attached to fix the rope 6 to the curved rope guide 14.

[0039] Protruding mounting pins (not shown in the figures) are attached to the terminal housing 10, to which suspension lugs are attached, with which the wedge guy clamp 4 is suspended from a mast of the overhead line. The cable 6 is generally a conductor cable of an overhead power transmission line. Accordingly, the guying device 2, in its assembled state, is mounted on a (guy) mast of such an overhead line.

[0040] In order to be able to clamp a rope 6 with a pressure-sensitive core 8 using such a wedge guy clamp 4 without the risk of damaging the pressure-sensitive core 8, the clamping wedges 12 are each provided with a groove 20, as explained in more detail in connection with FIGS. 2 to 4. FIG. 2 shows a top view of the clamping wedge 12 without the rope guide 14. FIG. 3 shows a view in the longitudinal direction L of the rear end face of the clamping wedge 12, and FIG. 4 shows an enlarged view of the area marked with the circle A in FIG. 3.

[0041] The respective clamping wedge 12 extends in the longitudinal direction L, in the transverse direction Q and in the vertical direction V, whereby these three directions form a Cartesian coordinate system. The respective clamping wedge 12 has a particularly monolithic base body 22 with an upper side, a lower side and two side surfaces. The base body 22 has a groove 24 introduced into the upper side, which extends in the longitudinal direction L over the entire length of the clamping area 13 and in particular over the entire length of the clamping wedge 12. The latter has a wall 26 as the groove base, which runs along a circular arc with a clamping radius R. The base body 22 typically has a rectangular cross-sectional shape - except for the groove 24 with the groove 22 - and the side surfaces therefore run parallel to one another.

[0042] The clamping radius R corresponds, in particular, to a radius of the cable assembly to be clamped. This clamping radius R is either determined by the radius of the cable 6 itself. Alternatively, in a design variant in which a protective spiral (not shown here) is attached at least in the clamping area around the cable 6, the clamping radius R corresponds to the radius of the cable assembly to be clamped, consisting of the cable 6 and the protective spiral.

[0043] The groove 24 has a radial depth T, which is smaller than the clamping radius R by a gap dimension x. Therefore, when the cable 6 is inserted, the two clamping wedges 12 are spaced apart at their parting plane by twice the gap dimension x. The radial depth T is defined by the distance in the radial direction / vertical direction V between the top of the clamping wedge 12 and the lowest point of the groove 24, without taking into account the groove 20 (see also FIG. 3).

[0044] As can be seen in particular from FIG. 4, the groove 20 has a groove base 28 and two lateral groove walls 30. The groove 20 has a groove depth t and a groove width b. The groove depth t is the distance in the radial direction / vertical direction V between the imaginary arc line of the clamping radius R and the groove base 28. The groove width b is the distance between the two groove walls 30 in the transverse direction Q at half the height of the groove depth t.

[0045] The groove depth t is generally smaller than the groove width b. In particular, it is, for example, in the range between 0.25 and 0.75 times the groove width b. In the exemplary embodiment, it is, in particular, approximately 1 / 2 the groove width b. Furthermore, the groove width b is in the range between one and three times the gap dimension x. In the exemplary embodiment, the groove width b is, in particular, twice the gap dimension x. The groove width b therefore preferably corresponds to the distance between the two clamping wedges 12.

[0046] The groove depth t generally corresponds to only a fraction of the total wall thickness of the clamping wedge 12 in the vertical direction V, namely at the rear, widest end of the clamping wedge 12. The wall thickness of the clamping wedge 12 at this rear end is, for example, 25 mm to 35 mm.

[0047] As can also be clearly seen in FIG. 4, the groove 20, viewed in cross-section, has no sharp-edged transitions. In particular, the groove walls 30 merge into the wall 26 of the channel 24, forming a rounded section. The groove base 28 also merges into the groove walls 30 in a rounded manner.

[0048] The groove width b thus widens starting from the groove base 28. The groove walls 30 are oriented obliquely to each other and enclose a groove angle a between them. This is, for example, in the range between 25 and 60° and, in the exemplary embodiment, particularly at 40°.

[0049] The wedge angle a of the respective clamping wedge 12, i.e., the angle at which the opposite boundary sides (top and bottom) of the respective clamping wedge 12 extend relative to each other, is typically in the range of a few degrees, for example, in the range of 1°-6°, and in the exemplary embodiment, approximately 2° to 4°, in particular 3°. The clamping wedges 12 (without the cable guide 14) typically have a length in the longitudinal direction L of, for example, 25 cm to 40 cm, and in the exemplary embodiment, in the range of 30 cm. The width of the clamping wedges 12 in the transverse direction Q (without extensions 16) is, for example, in the range between 3 cm and 8 cm, and in particular in the range of 5 cm. List of reference symbols

[0050] 2 guying device

[0051] 4 wedge clamps

[0052] 6 rope

[0053] 8 pressure-sensitive core

[0054] 10 terminal housings

[0055] 12 clamping wedge

[0056] 13 Clamping area

[0057] 14 rope guides

[0058] 16 Widening

[0059] 18 screw terminal

[0060] 20 grooves

[0061] 22 basic bodies

[0062] 24 gutter

[0063] 26 wall

[0064] 28 groove base

[0065] 30 groove wall

[0066] L longitudinal direction

[0067] Q transverse direction

[0068] V Vertical direction

[0069] R clamping radius

[0070] X gap size

[0071] T radial depth of the groove t groove depth b groove width a groove angle

Claims

Claims 1. Wedge guy clamp (4) for a cable (6), with two clamping wedges (12) extending in a longitudinal direction (L), and with a clamping housing (10) in which the clamping wedges (12) are received in the assembled state, wherein the clamping wedges (12) have a groove (24) extending in the longitudinal direction (L) for clampingly receiving the cable (6), characterized in that a groove (20) extending in the longitudinal direction (L) is introduced into the groove (24).

2. Wedge guy clamp (4) according to the preceding claim, characterized in that the groove (20) extends continuously over the entire length of at least one clamping area (13) and a cross-sectional contour formed by the channel (24) and the groove (20) and facing the cable (6) to be clamped is constant over this entire length of at least the clamping area (13).

3. Wedge guy clamp (4) according to one of the preceding claims, characterized in that the groove (24) has a wall (26) which runs along a circular arc with a predetermined clamping radius (R), wherein the clamping radius corresponds to a radius of a rope structure of the rope (6) to be clamped.

4. Wedge guy clamp (4) according to one of the preceding claims, characterized in that the groove (24) has a depth (T) which is less than the clamping radius (R) by a gap dimension (x) and that the groove (20) has a groove depth (t) and a groove width (b).

5. Wedge guy clamp (4) according to the preceding claim, characterized in that the groove width (b) is in the range between 0.5 times and five times the gap dimension (x) and in particular in the range between one and three times the gap dimension (x).

6. Wedge guy clamp (4) according to one of the two preceding claims, characterized in that the groove depth (t) is in the range between 0.5 times and 1.5 times the groove width (b) and in particular in the range up to a maximum of one time the groove width (b).

7. Wedge clamp (4) according to one of claims 4 to 6, characterized in that the groove depth (t) is smaller than the groove width (b).

8. Wedge guy clamp (4) according to one of the preceding claims, characterized in that the groove (20) merges in a rounded manner into the wall (26) of the channel (24).

9. Wedge guy clamp (4) according to one of the two preceding claims, characterized in that the groove (20) has a groove base (28) and two lateral, inclined groove walls (30), so that the groove (20) widens starting from the groove base (28).

10. Guying device (2) for guying a rope (6) with a wedge guy clamp (4) according to one of the preceding claims and a rope (6) clamped therein.

11. Guying device (2) according to the preceding claim, wherein the rope (6) has a pressure-sensitive core (8), in particular a carbon core.

12. Guying device (2) according to one of the two preceding claims, in which a protective spiral is attached around the rope (6) in the region of the wedge guy clamp (4).

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