DE2354459A1 - Surge suppressor with overpressure release and blow off flap - has radial nozzles diametrically opposite with one piece captive flap - Google Patents

Abstract

The overpressure release flap on the surge suppressor acts as an indicator. The two blow off nozzles are radial and are diametrically opposite each other. In normal conditions each opening is covered over by the flap which is made from a single stamping and is fixed to the underside of the end fitting. When there is a blow off the flaps pivot outward hinging at the bottom on thin flexible strips. They are clearly visible so as to act as an indicator of the pressure release. The flap can be made either from a weak non-elastic material which will remain in its deformed state or an elastic spring material forming part of the main spring.

Description

TRANSFORMERS ΠΝΙΟΝ AKTIENGESELLSCHAFT 7 Stuttgart-Bad Cannstatt, Deckerstraße 5

FST 7V4-7 Ln 'Stuttgart, October 19, 1973

PT-S / Lehmann / dk

Surge arrester with overpressure relief device and display

The invention relates to a surge arrester with an excess pressure relief device and a flap covering the exhaust opening.

Surge arresters consist of a series connection of spark arresters and voltage-dependent resistors, which are used as columnar component housed in an insulating housing, generally in a cylindrical porcelain support are. This support is on both sides by metallic end. fittings hermetically sealed. In case of a possible overload of the surge arrester, the G-housing must not burst as a result of excessive internal pressure

509820/0038

FST Λ

Pressure relief devices are provided in the end arm doors, those made of thin membranes, for example, made by peder pressure can consist of pressed-on end caps and the like.

In order to further reduce the risk of the housing bursting, is. it is already known and customary to relocate the arc burning inside to the outside by the fact that when responding the overpressure relief devices through the hot and ionized gases escaping to the outside from the end fittings suitable bends or deflectors along the outer jacket surface of the insulating housing are aligned from above and below each other, so that the arc, if necessary under Attachment of additional electrodes, "outside ignites.

There is already a known over-spam rank arrester that one Overpressure in the housing releases at least one opening and is provided with a deflection plate, which emerges from the opening Gases directed against the other fitting or earth, in which the exhaust opening of the deflector through a cover element is completed, which is firmly connected to the deflection plate only at one end and has a bending point in the vicinity of the fastening point, with the pressure relief device responding the outflowing gas bends the cover element away from the exhaust opening of the deflection plate and changes it in its Position as an electrode for an arc burning outside the insulating housing and at the same time as a display device serves to respond to the pressure relief device (DT-PS 1 290 241).

In this version there are special deflectors or bends provided on the end fittings, it being inevitable that the deflection device located at the lower end of the insulator has an opening which is open upwards and protrudes laterally beyond the outer jacket of the insulator.

- 3 π d 8 2 0/0 0 3 8

- * - ■ 235U59

FST 75A7 Ln - 3.

The object of the present invention is the horizontal running outlet openings in the end fitting of surge arresters to be covered with flaps so that they are in normal operation are closed, but the flaps are bent when the overpressure relief device responds and the blown out Gas flow along the outer surface of the insulator to ignite the external arc and, if necessary, a clearly visible display of the blowout that has taken place form.

According to the invention, this object is achieved in that the blow-out openings are directed radially at the end fittings, the flap closes the exhaust opening in the idle state and is held so that it is when blowing to the other end of the Arrester insulator opens out, acts as a deflection and at the same time serves as an overload indicator by changing its position.

Exemplary embodiments are shown on the basis of the accompanying drawings the invention and the mode of operation explained.

FIG. 1 shows the lower end fitting of a surge arrester, in which blow-out openings directed radially on both sides are provided, which are covered by the invention designed and fastened flaps 1 in normal operation. These flaps are held on one side and fastened to the end fitting 2 by means of rivets 3, for example.

The overpressure relief device consists of a closing plate 5 pressed by a spring 4 against the end of the insulating material housing 7 with the interposition of a seal 6 The two flaps are shown in broken lines in the bent state, with arrows on the right showing the gases being blown out as they are by the bent out The flap is deflected upwards along the outer surface of the insulator towards the upper armature. When closed, the flap is set back well below the mounting flange of the fitting and closes the blow-out space. ■■

5 "- 820/0 0.48 - 4 -

FST 73 / 4-7 Ln

Figure 2 shows a top view of such a flap with a mounting foot, it is clearly the arcuate surface of the cylinder the fitting adapted shape recognizable. To stiffen the arched Part of a stiffening bead 10 can be provided. There are two holes in the base to attach the flap to the end fitting appropriate.

Figure 3 shows another design of two flaps, the diametrically are attached to each other on the end fitting and through a diametrically continuous center piece 8 with each other are connected. Such a construction allows easier assembly of the two flaps in the end arm tube. Depending on the bending stiffness of the valve material used, it can be appropriate be special bending points in the shape of narrowed Provide webs 9 to ensure reliable bending.

The material of the flaps can advantageously be a relative soft and inelastic metal can be selected so that the deformation of the flap is retained when responding and no closing. spring back takes place. This makes it possible to clearly see an overload on the surge arrester, such as it is desired for operational reasons.

According to a further concept of the invention, there is an advantageous design of the cover flaps when the two-sided. Flaps and the connecting middle piece made of elastic spring material are made and the middle piece 8 is so high that it is the support and pressure spring for the end ceiling] 5 at the bottom of the isolator ^ the overpressure relief device forms.

FIG. 4 shows the pressure relief device designed in this way with cover flaps in the normal closed state, FIG. 5 when responding, the escaping gases again being indicated by arrows are. In this ostentatious representation,

5 *) 8 20/0 0.3 8

FST 73A7

simplification, the holding floor fitting is omitted.

Figure £> finally shows that of the two flaps 1, the connecting middle piece and the thin webs 9 provided
Bending points of the existing component in a flat development.

Due to the inventive design of the exhaust opening with cover flaps is a particularly reliable overpressure relief device downstream steering device, with overload indicator given.

0/0038

Claims (6)

TRANSFORMATOREN UNION AKTIENGESELLSCHAFT 7 Stuttgart-Bad Cannstatrt, Deckerstraße 5 FST 73Λ7 Ln Stuttgart, October 19, 1973 PT-S / Lehmann / dk Claims M.) Surge arrester with overpressure relief device and one covering the outer blow-out opening in the end fitting one-sided: fixed flap, characterized in that the blow-out openings on the end fittings are directed radially, the flap closes the exhaust opening in the rest state and is held so that it is opens when blown out to the other end of the arrester insulator, acts as a deflection and at the same time by changing its position serves as an overload indicator. 2. Surge arrester according to claim 1, characterized in that two flaps (1) each other on the end fittings are arranged diametrically opposite and both flaps (1) through a transversely continuous middle piece (8) are related to each other (Fig. 3, 4-, 5) 509820/0038 FST 75/51 3. Surge arrester according to claim 1 or 2, characterized in that that the flap is made of soft and inelastic material and remains in the deformed state. 4. Surge arrester according to claim 1 or 2, characterized in that that the flap is made of elastic spring material when it is a unit with the main compression spring forms. 5 · Surge arrester according to claim 4, characterized in, that the middle piece (8) is arched up and a plate (5) closing the pressure relief opening on the seal (6) (Fig. 4-, 5). 6. Surge arrester according to one of claims 2-5, characterized characterized in that the connection between the middle piece (8) and flap (1) consists of a bending point in the form of a there is a narrow web (9) (Fig. 3,6). 509820/0038 Blank page