Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
  • H02G7/00—Overhead installations of electric lines or cables
  • H02G7/14—Arrangements or devices for damping mechanical oscillations of lines, e.g. for reducing production of sound
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
  • H02G7/00—Overhead installations of electric lines or cables
  • H02G7/05—Suspension arrangements or devices for electric cables or lines
  • H02G7/06—Suspensions for lines or cables along a separate supporting wire, e.g. S-hook
  • H02G7/08—Members clamped to the supporting wire or to the line or cable

Definitions

• the invention relates to a support clamp for medium-voltage overhead lines with a flexible flap which forms a channel receiving the overhead line and has an opening for the carrier at its end portion to be connected to a carrier.
• support terminals for medium-voltage overhead lines have a hook-shaped terminal body made of sheet steel.
• the hook-shaped part forms a groove in which a foam-like slot slits in the longitudinal direction
• Sleeve is fixed, which includes the section of the line lying in the groove in the assembled state of the support clamp.
• this support clamp is rigid. In addition, their holding force is low compared to tensile forces that act in the longitudinal direction of the line.
• a known support clamp of the type mentioned at the outset (FR 2550394 A1) has a higher holding force than tensile forces acting in the longitudinal direction of the line, which has a flexible but non-stretchable tab, one end of which is connected to a frame-shaped ring body through which the tab is located Forming a contractible loop is passed.
• the holding force therefore increases with the tensile load on the tab. In many cases, however, this is not desirable.
• this support clamp is just as unable to counteract vibrations of the line as the known support clamps with a metallic clamp body.
• the invention has for its object to provide an improved support terminal for medium voltage overhead lines.
• the support clamp according to the invention is inexpensive since no other parts are required apart from the tab. Installation is also very easy. All that is required is that the tab already suspended in the carrier in the region of its one end section is guided around the line and with its other
• the support clamp according to the invention therefore counteracts the formation of vibrations in the line.
• it can greatly reduce forces that can act on the line by stretching so far that the line is not damaged and in particular the connection of the support clamp to the carrier is not released, as is the case with the known support clamps with overload protection Case is.
• the line can therefore automatically return to the normal position as soon as the external influences that led to the high load have ceased.
• the tab is made
• the support clamp according to the invention can also be used for uninsulated overhead lines or only insulated for a fraction of the operating voltage.
• the middle section of the tab has a greater width than the two end sections. This ensures that the overhead line is supported on the tab over a sufficiently long section, but the end sections of the tab only need to be selected as wide as is expedient to achieve the desired load-bearing capacity and elongation.
• the central section of the tab has one of its two edge areas towards the center
• the support clamp does not stress the kink, since the supporting effect of the two edge areas decreases towards the edge.
• the widening of the middle section compared to the two end sections is also advantageous in that the two edge regions of the middle section can then be designed as sleeves which at least largely encompass the overhead line and which likewise contribute to vibration damping.
• the middle section and the passage opening can be divided by at least one dividing the tab into parallel strands
• Recess are increased, which preferably extends in the longitudinal direction of the tab.
• the tab cross section is then reduced only in this area.
• At least one element forming a screen can be molded onto the tab in the area between the central section and the passage opening.
• Such elements which, as with conventional insulators, significantly increase the creepage distance, can be advantageous, for example, if the conductor is uninsulated.
• FIG. 3 shows a section along the line III - III of FIG. 1, 4 is a side view of the second embodiment in the assembled state,
• Fig. 5 is an end view of the second embodiment in the assembled state.
• the central section 3 of the tab forms a sleeve which, in the assembled state, comprises the overhead line 2.
• the two identically designed end sections of the tab which abut one another in the assembled state of the support clamp 1 and at least substantially keep the sleeve formed by the central section 3, each form a band-shaped carrier for the central section 3. They are therefore in the region of their free end a passage opening 5 provided for the passage of a bolt-shaped carrier 6, usually made of steel.
• the strap forming the support clip 1 is made of silicone rubber.
• the tab is therefore not only flexible. In particular, their two end sections 4 are therefore also stretchable in the longitudinal direction of the tab. Since this extensibility is desired in order to be able to reduce mechanical loads on the overhead line 2, such as occur, for example, when a tree or branches of a tree fall on the overhead line 2, the
• the longitudinal extensibility of the two central sections 3 is increased significantly in that they are provided in the region between the central section 3 and the passage opening 5 with an elongated hole 7 which divides the end section 4 into two parallel strands. Thanks to the great flexibility of the two end sections 4, it is not necessary to provide the support for the support clamp with an overload release device, which to avoid tearing off the overhead line 2 at a certain load on the support terminal releases it. Rather, the ered sections 4 are dimensioned such that they tear off when the upper limit of the load capacity of the overhead line 2 is reached.
• the support clamp 1 in conjunction with the longitudinal extensibility of the end sections 4, also effectively counteracts the formation of vibrations in the overhead line 2. Furthermore, the static friction between silicone rubber and steel is relatively large. Friction between the end sections 4 in the region of their passage opening 5 and the carrier 6 is therefore at least very largely prevented.
• the central section 3 is significantly widened compared to the two end sections 4.
• the width of the middle section 3, which corresponds to the length of the sleeve formed by the middle section 3, is a multiple of the width of the end sections 4. This practically completely eliminates the stress on the overhead line 2 in the section carried by the middle section 3. To avoid such buckling stress further contributes to the fact that the central section 3 has a thickness increasing from its two edges towards the center. As a result, the wall thickness of the sleeve formed by the central section 3 decreases from the maximum value which it has on the half length coinciding with the longitudinal center line of the end sections 4 towards the free ends.
• the deformability of the sleeve therefore increases towards its two ends, which ensures that the overhead line 2 is not subjected to any buckling stress when it emerges from the sleeve. Since the two end sections of the sleeve formed by the middle section 3 when the overhead line 2 vibrates
• the support clamp 1 Since the overhead line 2 is pressed against the central section 3 of the support clamp 1 and the static friction of silicone rubber is relatively high, the support clamp 1 has a relatively large one
• the mounting of the support clamp 1 is extremely simple. Either only the carrier 6 is first passed through the passage opening 5 of the one end section 4 and then the tab forming the support clamp 1 is placed around the overhead line 2 such that it comes to rest in the sleeve formed by the central section 3. Then only the second end section 4 needs to be hooked into the carrier 6 with the aid of its passage opening 5. However, one can of course also first form the support clamp 1
• the exemplary embodiment shown in FIGS. 4 and 5 differs from the exemplary embodiment according to FIGS. 1 to 3 only in that the two end sections 104 of the tab forming the integrally formed support clamp 101 are not divided into individual strands and that, as shown in FIG .4 and 5 show, on the two end portions 104 shield elements 108 are formed, which complement one another in the assembled state of the support clamp 101, in the exemplary embodiment two shields.
• These shields have the isolators usual shape and protrude on all sides over the two end sections 104 which abut one another in the assembled state of the support clamp 101.
• the support terminal 101 therefore has a leakage current path which is substantially longer than that of the support terminal 1 and is therefore also particularly suitable for medium-voltage overhead lines 102 which have no insulation.
• the shield elements 108 are provided with a trapezoidal groove or
• the longitudinal stretchability of the end sections 104 is not impaired by the screen elements 108.
• the longitudinal extensibility could also be increased here by dividing it into parallel strands as in the embodiment according to FIGS. 1 to 3.

Landscapes

• Suspension Of Electric Lines Or Cables (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6437702

Family Applications (1)

Country Status (2)

Citations (2)

Family Cites Families (1)

• 1991
  • 1991-08-03 DE DE19914125854 patent/DE4125854C1/de not_active Expired - Fee Related
• 1992
  • 1992-07-22 WO PCT/EP1992/001661 patent/WO1993003525A1/de active Application Filing

Patent Citations (2)

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