SURGE ARRESTER AND METHOD FOR INSTALLING A SURGE ARRESTER

20210005363 ยท 2021-01-07

    Inventors

    Cpc classification

    International classification

    Abstract

    A surge arrester includes a tubular housing and an end fitting which is connected to one end of the housing and on which a column having at least one electrical resistor is disposed. A support abuts the inner surface of the tubular housing in the region of the end fitting. The support has a recess in the longitudinal direction of the surge arrester, into which a pressure device is inserted. A method for installing a surge arrester is also provided.

    Claims

    1-15. (canceled)

    16. A surge arrester, comprising: a tubular housing having an end and an inner surface; an end fitting connected to said end of said housing; a column disposed on said end fitting, said column having at least one electrical resistor; a support abutting said inner surface of said tubular housing in a region of said end fitting, said support having a recess formed in a longitudinal direction of the surge arrester; and a pressure device inserted in said recess.

    17. The surge arrester, according to claim 16, wherein said pressure device is wedge-shaped.

    18. The surge arrester according to claim 16, wherein said pressure device is form-lockingly disposed in said recess.

    19. The surge arrester according to claim 16, wherein: said recess has two contact regions contacting said pressure device; said contact regions each have a guide groove; said pressure device has sides facing said contact regions and a respective guide projection on each of said sides; and said guide projections are disposed in said guide grooves.

    20. The surge arrester according to claim 19, wherein said guide grooves and said guide projections fix said pressure device on said support and produce a cylinder-barrel-shaped outer contour of said pressure device and said support being pressed against said inner surface of said tubular housing without damage.

    21. The surge arrester according to claim 16, wherein said support is a hollow cylinder.

    22. The surge arrester according to claim 16, wherein said pressure device is one of a plurality of pressure devices, said recess is one of a plurality of recesses, and said support has a plurality of hollow cylinder segments forming said plurality of recesses for receiving said plurality of pressure devices in an installed state.

    23. The surge arrester according to claim 16, wherein said support forms a ring-shaped step in which said column is form-lockingly received.

    24. A method for installing a surge arrester, the method comprising: placing a support on an inner surface of a tubular housing; and inserting a pressure device into a recess formed in the support in an insertion direction extending in a longitudinal direction of the tubular housing.

    25. The method according to claim 24, which further comprises using a wedge-shaped pressure device as the pressure device.

    26. The method according to claim 24, which further comprises placing the pressure device form-lockingly in the recess.

    27. The method according to claim 24, which further comprises: providing the support with two contact regions contacting the pressure device; providing each of the contact regions with a guide groove; providing the pressure device with respective guide projections on sides facing the contact regions of the support; and inserting the guide projections into the guide grooves.

    28. The method according to claim 24, which further comprises using the guide grooves and the guide projections to fix the pressure device on the support and produce a cylinder-barrel-shaped outer contour of the pressure device and the support being pressed against the inner surface of the tubular housing without damage.

    29. The method according to claim 24, which further comprises providing the support with a plurality of hollow cylinder segments forming a plurality of recesses for receiving a plurality of pressure devices in an installed state.

    30. The method according to claim 24, which further comprises using the support to form a ring-shaped step in which a column having at least one electrical resistor is form-lockingly received.

    Description

    [0017] To better explain the invention, preferred embodiments are shown in a schematic illustration in the figures, which show:

    [0018] FIG. 1 a first embodiment of an inventive surge arrester, and

    [0019] FIG. 2 a first detailed view of a second embodiment of an inventive surge arrester, and

    [0020] FIG. 3 a cross-section of the second embodiment according to FIG. 2, and

    [0021] FIG. 4 a second detailed view of the second embodiment according to FIG. 2, and

    [0022] FIG. 5 a third detailed view of the second embodiment according to FIG. 2.

    [0023] FIG. 1 shows a first embodiment of an inventive surge arrester 1. The surge arrester 1 has a tubular housing 2 which is adjoined by respective end fittings 3, 4 in the longitudinal direction of the arrester 1. The tubular housing 2 is equipped with an insulation layer 11 of silicone between the end fittings 3, 4. Alternatively, another material, such as ethylene propylene diene M-class rubber (EPDM), for example, can also be used for the insulation layer 11. The insulation layer 11 has shields for extending the creepage path between the end fittings 3, 4. Support means 5, 6 are provided to improve the bending strength of the tubular housing 2 at the end regions. The support means are formed as hollow cylinders with recesses 9, 10. The recesses 9, 10 are formed in a wedge shape. Wedge-shaped pressure means 7, 8 are inserted in the wedge-shaped recesses 9, 10. By displacing the wedge-shaped pressure means 7, 8 in the longitudinal direction of the tubular housing within the recesses 9, 10, the support means 5, 6 can be spread apart and thereby pressed against the inner surface of the tubular housing. This pressing action brings about a reinforcement of the housing in the region of the end fittings and therefore an increased bending strength in this region. In this example, the wedge-shaped recesses are created in such a way that they face the respective end fitting 3, 4 with their wider end.

    [0024] FIG. 2 shows a first detailed view 20 of a second embodiment of the inventive surge arrester. The support means in this embodiment is formed by four hollow cylinder segments 6, 17, 18, 19, which form wedge-shaped recesses 10, 11, 13, 15. Wedge-shaped pressure means 7, 12, 13, 16 are inserted into these wedge-shaped recesses 10, 11, 13, 15 with form locking and bring about a pressing action against the tubular housing 2. In this case, the wedge-shaped recesses in this embodiment face the end fittings 3, 4 with their narrower end.

    [0025] FIG. 3 shows a cross-section 30 of the embodiment 20 according to FIG. 2. The hollow cylinder segments 6, 17, 18, 19 each form two contact regions 50-57 with the pressure means 7, 12, 14, 16 in their recesses. These contact regions 50-57 each have a guide groove 58-65, which is formed to be parabolically rounded in this example. The parabolic form is simple to manufacture and offers good slip resistance. The pressure means 7, 12, 14, 16 each have, at their sides facing the contact regions 50-57, a guide projection which is arranged in the respective guide groove 58-65. The interaction between the guide grooves and guide projections means that the pressure means cannot slip out of the hollow cylinder segments in the transverse direction. The pressure means and the hollow cylinder segments form a substantially cylinder-barrel-shaped outer contour of the pressure means and support means, which can be pressed against the inner surface of the tubular housing without damage.

    [0026] FIGS. 4 and 5 shows a second and a third detailed view of the second embodiment. In this case, it can be seen that the hollow cylinder segments 17, 18, 19 and also the pressure means 14, 16 are created in such a way that they form two steps 32, 33 extending in the shape of a ring. It can furthermore be seen that the pressure means 14, 16 have projections 30, 31. These projections 30, 31 form a further step 34, which serves as a bearing surface for a column with variable resistors. In this case, the bearing surface 34 is consequently formed by the projections 30, 31.