DE7030706U - LOW-LIQUID CIRCUIT BREAKER. - Google Patents

Description

56/70

Hw / Gu

Public limited company Brown, Boveri & Cie., Baden (Switzerland)

Low-liquid circuit breaker,

The invention relates to a low-liquid circuit breaker with additional injection of extinguishing liquid _n the Extinguishing chamber, using a connected to a switching pin and movably arranged in a pump cylinder Piston, a storage space assigned to the pump cylinder, in which extinguishing liquid is conveyed during switch-on and through the extinguishing chamber during switch-off flows back there.

It is already known to assign a rigidly tfamit connected piston to the movable contact of a circuit breaker, the during the switch-off movement, a beam is released j generated, which is guided along the movable contact and directed against the fixed contact.

It is already part of the state of the art, the pump cylinder to allocate a storage space into which extinguishing liquid is conveyed from an intermediate part during the switch-on movement,

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which flows back into the intermediate part during the opening movement by the extinguishing chamber and then through a space between the quenching chamber and an insulator and that both between the quenching chamber and the storage space, are as well arranged between the storage space and the .. ischenteil valves aie backflow of To prevent extinguishing liquid.

However, the disadvantage is that in the arc gap no or only a slight overburden can be formed and even with the support of the self-generated transverse blowing by extinguishing liquid from a separately arranged source, which is injected under pressure into the extinguishing chamber, Until now, the amount of liquid injected into the extinguishing chamber could only be the same during the entire switch-off movement be kept large.

It is the object of the invention to create an arrangement which does not have the disadvantages and shortcomings of the known having.

The above-mentioned object is achieved in that the pump piston, which is rigidly connected to the switching pin, enters the extinguishing chamber The amount of extinguishing liquid delivered is changed independently of the switch-off movement.

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The arrangement according to the invention ensures that the required © Lijaohflüeaigkeit during the switch-off movement of the switching pin changes both in terms of quantity and, depending on Position of the pump piston, which is rigidly connected to the switching pin, also the pressure of the release fluid injected into the extinguishing chamber quality varies.

According to a preferred embodiment of the invention are between the pump cylinder and an intermediate chamber bypass openings arranged. It is advisable to choose different sized cross-sections for these bypass openings. Through this Arrangement is achieved that the amount of extinguishing liquid displaced by the pump piston and injected into the extinguishing chamber on The beginning of the switch-off movement is less than at the end of the same.

According to a further embodiment of the invention, the with The pump piston rigidly connected to the switching pin is designed as a double piston.

With this arrangement, at the beginning of the switch-off movement the main piston accommodating the smaller piston displaces a larger amount of extinguishing liquid at the beginning of the switch-off movement and, after the main piston has been held back by a stop located in the pump cylinder, during the further movement of the small piston, a smaller amount of extinguishing liquid is injected into the extinguishing chamber.

Exemplary embodiments of the subject matter of the invention are shown in the drawing shown schematically.

It shows:

Pig, 1: a cross section through the pump arrangement of a low-liquid power switch ',

Fig. La shows a cross section through the pump cylinder and the space;

Fig. 2: a longitudinal section through a low-liquid power switch ter;

FIG. 2p shows a longitudinal section rotated by 90 in relation to FIG. 2 through a low-liquid circuit breaker; FIG.

Fig. 3: a longitudinal section through a pump arrangement irr'.ζ double piston for a low-liquid circuit breaker.

The same parts are given the same reference numbers in the individual figures been provided.

According to FIG. 1, 1 denotes an insulator housing of a low-liquid circuit breaker, in which an extinguishing device is arranged. A pump piston 2 is rigidly connected to a switch pin 3 and moves up and down in a pump cylinder 4 as a result of the switching on and off movements of the switch pin 3. Bypass openings 5, which are of different sizes, are arranged on one side of the piston cylinder *

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Have cross-sections. The 3ypass-0ef for only 5 steep a connection to an intermediate, r.er. -aurn 6, while through an opening 7 on the opposite! erring side of the Purr.penzyi ^ nders stones connection to a pressure chamber 8 is created, the '. ederum is connected to the oil reservoir on its underside via a check valve 9 and a connecting line 10 and on its upper side has an opening 11 with a valve 12 , which forms a connection to an extinguishing chamber 1J> * The space 6 is via openings I ² J- , 15 with e: ^ .ern low pressure chamber 16, which also leads to the extinguishing agent reservoir, connected.

In FIG. 2, 1 again denotes the insulator housing of a low-liquid circuit breaker; the switch pin J> with the pump piston 2 rigidly connected to it is in the "Off" switch position.

The switch-off movement is shown in FIG. 2a. The side edge of the pump piston 2 just covers one of the bypass openings 5 and thus controls the amount of extinguishing liquid injected into the extinguishing chamber 15 via the pressure chamber 8 as a function of the stroke.

In Fig. 3, 3 designates a switching pin, which with a double piston, consisting of a main piston 1? and a secondary piston l8 is connected. The one from HauptWolben 17

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and Nebenkoiι. ϊ5 usani.-e "» set double piston moves in a pump cylinder 4 --t ·. / ^ calculating the in and out tben of the switching pin 3 up and down.

The main piston IJ has a recess 20 which receives the secondary piston 18 when the switching position is in its uppermost position. The pump cylinder 4, together with the stop 19 > , likewise has a connection opening 7 which leads to the pressure chamber 8.

All design features not necessary for a direct understanding of the invention, for example the actuation device of the low-liquid circuit breaker, are in the Figures 1 to j $ have been omitted.

The mode of operation of the arrangement according to the invention is based the following:

If the switching pin 5 and the pump piston 2 rigidly connected to it move downwards during a switch-off movement, the extinguishing fluid located in the pump cylinder 4, in the intermediate space 6 and in the pressure space 8 flows through the pump piston 2 pressed together and part of the same escapes through the bypass openings 5 via the intermediate space 6 and the openings l4 and 15 in the low pressure chamber 16, while the other part

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the extinguishing liquid through the connection opening 7 into the
"i'druckraum 8 arrives, and through the valve 12
. -Long closed opening 11 is pressed into the Lcschkarr.rr.er 13. Since in the pressure chamber δ by Λ "c 'ärtsbewegung of the pump piston 2 results in a corresponding üeberdruck, the check valve 9 v.ird closed. When Einschaitbewegur.g flows from the Oeivorratsraum via the connection line 10 extinguishing liquid in the pressure chamber 8, the pump cylinder 4 and the space 6th

As the extinguishing liquid passes through the bypass openings 5 into the space 6 or the Nieäerdruckrau.-n 16, the amount of extinguishing liquid injected into the extinguishing chamber 13 at the beginning of the switch-off movement is less than towards the end of the switch-off movement, because then the greater part of the Bypass openings 5 is closed by the downward moving pump piston 2 and the amount of extinguishing agent located in the pump cylinder K can only pass through the connection opening 7 into the pressure chamber 8 and from there through the open valve 12 of the extinguishing chamber 1J> . ,

If a double piston is used, this is included the switch position "On" in its uppermost position. In the The switching pin 3 together with the pump piston, consisting of the main piston 17 and the secondary piston, is switched off

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moves down, and displaces: thus first the part of the extinguishing liquid that is in the pump cylinder above de3 stop 19 through the connection opening 7 into the pressure chamber 8 and from there into the extinguishing chamber 15- As soon as the main piston 17 ^. When the stop 19 has been reached, it is held back by the latter and the secondary piston 18 continues to move downward with the switching pin 3, whereby the remaining amount of extinguishing fluid also passes through the opening 7 into the pressure chamber 8. As a result, the amount of extinguishing agent initially injected into the extinguishing chamber is greater and, at the end of the disengaging movement, corresponding to the smaller cross section of the secondary piston 18, is lower.

The direction of flow of the extinguishing liquid is indicated by arrows indicated in the drawings.

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Describing useful lists

1 - Isolatorisehäuse 'd - rumpenkolbeii

3 - switch pin

4 - pump cylinder

5 - Bypass O 'openings

6 - space

7 - connection opening θ - pressure space 9 - check valve

10 - connecting line

11 - opening

12 - valve

15 - extinguishing chamber

14 - openings

15 - openings

16 - low pressure room

17 - main piston

18 - secondary piston

19 - stop

20 - recess

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Claims (3)

Claims . No-liquid circuit-breaker "with additional F." r Spritzunp: from extinguishing liquid into the extinguishing chamber, ur.ter Verwondunp; "Ines with the switching pin connected and movably arranged in a pump cylinder Pur.penkolbens, a 3speicherraur.es assigned to the pump cylinder, into which extinguishing liquid is conveyed during switch-on and flows back through the extinguishing chamber during switch-off, characterized in that the by the pump piston (2), which is rigidly connected to the switching pin (3), into the extinguishing chamber (13), the amount of extinguishing liquid delivered is changed as a function of the stroke via the disengaging movement. 2. Low-liquid circuit breaker according to claim, characterized in that ^{bypass openings (5) are arranged between the pump cylinder (2} O and an intermediate space (6). 3. Low-liquid circuit breaker according to claims 1 and 2, characterized in that the bypass Oeffr.unren (5) have different sized cross-sections. Ί. Low-liquid circuit breaker according to the claims Ibis3, characterized in that the in the extinguishing chamber (13) Volume of liquid conveyed at the beginning of the switch-off ev. event: 703878617.2.72 - ίο - ^ f / " ⁷ : less aj.s at the end of which is. 5- low-liquid circuit breaker according to claim 1 _; characterized in that the pump piston (2) is designed as a double-pole piston, consisting of a main piston (17) and a secondary piston (1Ξ). 6 = low-liquid performance ^ e-age according to the claims 1 and 5, characterized in that the amount of liquid conveyed into the extinguishing chamber (13) is greater at the beginning of the switch-off movement than at its end. CkQWN, BüVERi d Ci *. 703171617.2.72