Circuit breaker

Abstract

A circuit breaker for connecting at least two line sections in an interruptible manner has at least one pair of vacuum tubes, each with a stationary switching contact and a movable switching contact. The switching contacts of the vacuum tubes are electrically connected in series. The movable switching contacts of the vacuum tubes are coupled to a common actuator and can be simultaneously switched by a movement of the actuator.

Claims

1. A circuit breaker for an interruptible connection of at least two sections of line, the circuit breaker comprising: a pair of vacuum tubes each having a fixed switching contact and a movable switching contact, said switching contacts of said pair of vacuum tubes being electrically connected in series, and said vacuum tubes being arranged in a common housing; a common actuator coupled to said movable switching contacts of said vacuum tubes and being configured to be simultaneously switched by a movement of said actuator; and a common actuating element coupling said movable switching contacts to said actuator; said pair of vacuum tubes being one of three pairs of vacuum tubes; said switching contacts of said vacuum tubes of each said pair are electrically connected in series with two sections of line; said pairs of vacuum tubes are disposed at a spacing distance from one another in each case in a longitudinal direction of said actuating element; said actuating element being coupled to said movable switching contacts of said vacuum tubes of said three pairs.

2. The circuit breaker according to claim 1, wherein said common actuating element is a rotating shaft or a linearly movable actuating element.

3. The circuit breaker according to claim 1, wherein said common actuating element is a crankshaft.

4. The circuit breaker according to claim 1, further comprising connecting rods respectively coupling each of said movable switching contacts of said vacuum tubes to said common actuating element.

5. The circuit breaker according to claim 4, wherein at least one of said actuating element or said connecting rods consist of an electrically insulating material.

6. The circuit breaker according to claim 5, wherein said electrically insulating material is at least one material selected from the group consisting of glass-fiber-reinforced plastic and Kevlar®-reinforced plastic.

7. The circuit breaker according to claim 1, wherein said vacuum tubes of said pair of vacuum tubes are arranged at an angle to one another such that said movable switching contacts are directed toward and coupled to said actuating element, and wherein said actuating element is arranged between said vacuum tubes.

8. The circuit breaker according to claim 1, wherein said actuator is an electric motor.

9. The circuit breaker according to claim 1, wherein said common housing is a dead-tank circuit breaker housing or a live-tank circuit breaker housing.

10. The circuit breaker according to claim 1, wherein said housing is formed with feedthroughs and each of said vacuum tubes is arranged in a respective said feedthrough, and each of the sections of line is fed through a respective said feedthrough into the housing.

11. The circuit breaker according to claim 10, wherein said feedthroughs are arranged at an angle relative to one another in a housing top of said housing, and said actuating element is arranged between and below said feedthroughs.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 shows a representation of a first exemplary embodiment of a circuit breaker according to the invention,

(2) FIG. 2 shows a representation of a vacuum tube,

(3) FIG. 3 shows a first exemplary embodiment of a movement mechanism of a circuit breaker according to the invention,

(4) FIG. 4 shows a second exemplary embodiment of a movement mechanism of a circuit breaker according to the invention, and

(5) FIG. 5 shows a second exemplary embodiment of a circuit breaker according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(6) In FIG. 1, a schematic representation of a first exemplary embodiment of a circuit breaker 1 according to the invention is shown. The circuit breaker 1 according to the invention comprises a housing 2, two feedthroughs 4 being arranged at an angle to one another in a housing top 3 of the housing 2. Respectively arranged in each of the feedthroughs 4 is a vacuum tube 5 of a pair of vacuum tubes 5. The vacuum tubes 5 respectively comprise a fixed switching contact 6 and a movable switching contact 7, the fixed switching contact 6 being connected to a section of line 9 by way of an electrical connection 8. The construction of a vacuum tube 5 is explained more specifically below with reference to FIG. 2.

(7) The pair of vacuum tubes 5 serves for the interruptible connection of the two sections of line 9. For this purpose, the two movable switching contacts 7 are respectively connected by way of a sliding contact to a conductor 10, so that the movable switching contacts 7 of the vacuum tubes 5 are electrically connected to one another, at least in the closed state or in the conducting state of the vacuum tubes 5. When the switching contacts 6, 7 are closed, that is to say when the circuit breaker 1 is closed, the sections of line 9 are electrically connected to one another.

(8) The movable switching contacts 7 are connected to an actuator 13 by way of a movement mechanism 11 comprising an actuating element 12. By a movement of the actuator 13, the movable switching contacts 7 of the vacuum tubes 5 can be switched simultaneously. Closed switching contacts 6, 7, that is to say conductive vacuum tubes 5, can be simultaneously switched by a movement of the actuator 13 from the closed position into the open position by movement of the movable switching contacts 7. Conversely, it is also possible that, by a further movement of the actuator 13, in particular in an opposite direction of movement, the movable switching contacts 7 are brought from the open position, that is to say the blocking position, into the closed position. In this way, the connection between the sections of line 9 can be interrupted or an interrupted connection can be reconnected.

(9) The integration of the vacuum tubes 5 in the feedthroughs 4 of the housing 2 makes a space-saving arrangement of the vacuum tubes 5 inside the housing 2 possible. Furthermore, the arrangement of the vacuum tubes 5 at an angle to one another, that is to say an arrangement of the vacuum tubes in a V shape, makes it possible for simultaneous switching of the vacuum tubes 5 to be easily realized by way of the actuating element 12 and the actuator 13.

(10) The housing 2 may be for example a dead-tank circuit breaker housing, which is at a ground potential. As an alternative to this, the housing 2 may also be a live-tank circuit breaker housing, which is insulated with respect to the outside. In the example shown here, it is a dead-tank circuit breaker housing, the sections of line 9 being insulated from the housing 2 not only by the schematically drawn ceramic insulators 14 but also by way of the vacuum tubes 5. The interior 15 of the housing 2 may also be filled with an insulating gas, for example with dehumidified air or sulfur hexafluoride, for insulation.

(11) In FIG. 2, a schematic sectional view of a vacuum tube 5 is represented. The vacuum tube 5 comprises an airtight capsule 16, which consists of an insulating material and the interior 15 of which is evacuated. Both the fixed contact 6 and the movable contact 7 are fed into the interior 15 of the capsule 16. For sealing the vacuum in the interior 15 of the capsule 16 in the region of the movable switching contact 7, a bellows 17 of an airtight material is provided. By a movement of the movable switching contact 7, as indicated by the arrow 18, an electrical connection between the fixed switching contact 6 and the movable switching contact 7 can be established or interrupted. If the movable switching contact 7 has moved toward the fixed switching contact 6, so that the contact pieces 19 of the fixed and movable switching contacts 6, 7 come into contact, the switching contacts 6, 7 are closed and there is a conductive connection between the fixed switching contact 6 and the movable switching contact 7. Conversely, with contact pieces 19 that are in contact, an electrical connection between the switching contact 6 and the movable switching contact 7 can be interrupted, by the movable switching contact 7 being moved away from the fixed switching contact 6. The region of the contact pieces 19 is partially surrounded by a shield 20 of an electrically conductive material, which serves for shaping an electrical field that forms in the interior 15 of the capsule 16 and for limiting the spread of metallic material of the switching contacts 6, 7 that has vaporized during the switching operations.

(12) As shown in FIG. 1, for example the fixed switching contact 6 of a first vacuum tube 5 may be connected by way of the electrical connection 8 to a section of line 9 and the movable switching contact 7 may be connected by way of the conductor 10 to the movable switching contact 7 of a second vacuum tube 5, the fixed switching contact 6 of the second vacuum tube 5 likewise being connected to a section of line 9 to be connected. In this way, a series connection of the vacuum tubes 5 is realized, making it possible to realize a switchable connection of two sections of line 9 at voltage levels above the rated voltage of a single one of the vacuum tubes 5.

(13) In FIG. 3, a first exemplary embodiment of a movement mechanism 11 for switching the vacuum tubes 5 is represented. In this case, the actuating element 12 is configured as a crankshaft, which is coupled to the movable contacts 7 of the vacuum tubes 5 arranged in a V shape in each case by way of a connecting rod 21. The connecting rods 21 are fastened in each case by way of a rotary bearing 22 to the movable switching contacts 7 and to the crankshaft. The actuating element 12 can be turned in the direction of the arrow 23 by the actuator 13, which is for example configured as an electric motor. The rotary movement of the actuating element 12 has the effect of creating a distance between the movable switching contacts 7 and the fixed switching contacts 6, and consequently opening the switching contacts 6, 7. Conversely, when there is rotation opposite to the direction of the arrow 23, a movement of the fixed switching contacts 7 toward the fixed switching contacts 6 can take place, so that the switching contacts 6, 7 can be closed, and consequently the vacuum tubes 5 can be electrically conductively connected.

(14) In FIG. 4, a second exemplary embodiment of the movement mechanism 11 of a circuit breaker 1 according to the invention is represented. In this exemplary embodiment, the actuating element 12 is configured as a linearly movable actuating element, with which, as described above, the movable switching contacts 7 of the vacuum tubes 5 are coupled in each case by way of a connecting rod 21 and two rotary bearings 22. The linearly movable actuating element 12 is mounted in a guide 24 and is coupled to the actuator 13, for example an electric linear motor, which is not represented in FIG. 4. The linearly movable actuating element 12 can be moved by the actuator 13 in the guide in the direction of the arrow 25, in order to open the switching contacts 6, 7 by movement of the movable switching contacts 7. Closing of the switching contacts 6, 7 can take place correspondingly by movement of the linearly movable actuating element 12 counter to the direction of the arrow 25, so that the movable switching contacts 7 are again moved into contact with the fixed switching contacts 6.

(15) In FIG. 5, a second exemplary embodiment of a circuit breaker 1 according to the invention is represented. The circuit breaker 1 comprises three pairs 26 of two vacuum tubes 5 each, which are arranged offset along a longitudinal direction of the actuating element 12. Each of the pairs 26 of the vacuum tubes 5 serves for the switchable connection of two sections of line 9. As a result of the use of three pairs 26 of vacuum tubes 5, it is made possible by the circuit breaker 1 to switch electrical connections in a three-phase power system, each pair 26 of the vacuum tubes 5 respectively switching a phase. The movable switching contacts 7 are coupled to the actuating element 12 by way of the connecting rods 21 and the rotary bearings 22. The movement mechanism may in this case be configured in a way corresponding to the exemplary embodiments shown in FIG. 3 or 4. By a movement of the actuator 13, a simultaneous movement of all the movable switching contacts 7 of the pairs 26 of vacuum tubes 5 can take place, so that all three phases can be switched simultaneously by the circuit breaker 1. It goes without saying that the movable switching contacts 7 of a pair 26 of vacuum tubes 5 are conductively connected, for example in each case by way of a conductor 10 as shown above in relation to FIG. 1, so that the two sections of line 9, which are electrically connected to the vacuum tubes 5 of a pair 26, are electrically conductively connected or electrically isolated, depending on the switching state of the vacuum tubes 5.

(16) It goes without saying that, also in the case of the configuration of a circuit breaker with three pairs 26 of vacuum tubes 5, the vacuum tubes 5 may be respectively arranged in a V shape, as shown above. In addition or as an alternative to this, it is possible that the vacuum tubes 5 are in each case arranged in a feedthrough 4 in the housing top 3 of a housing 2 of the circuit breaker 1, so that overall an altogether compact construction is also achieved for the circuit breaker 1 for switching three-phase current. In this exemplary embodiment, the actuator 13 is located outside the housing 2, the actuating element 12 being fed through an outer wall of the housing 2 and connected to the actuator 13. It goes without saying that it is also possible that the actuator 13 is arranged inside the housing 2.

(17) In order to insulate the actuator 13 from the high voltage, it may be provided in all of the exemplary embodiments that the actuating element 12, or the crankshaft or the linearly movable actuating element, and also the connecting rods 21 consist of an insulating material, such as a glass-fiber-reinforced plastic or a Kevlar-reinforced plastic. In this way, a current flow through the movement mechanism 11 or the actuating element 12 to the actuator 13 is also prevented when the circuit breaker 1 is closed.

(18) Although the invention has been illustrated more specifically and described in detail by the preferred exemplary embodiment, the invention is not restricted by the examples disclosed and other variations may be derived therefrom by a person skilled in the art without departing from the scope of protection of the invention.

LIST OF REFERENCE SYMBOLS

(19) 1 Circuit breaker

(20) 2 Housing

(21) 3 Housing top

(22) 4 Feedthrough

(23) 5 Vacuum tube

(24) 6 Fixed switching contact

(25) 7 Movable switching contact

(26) 8 Electrical connection

(27) 9 Section of line

(28) 10 Conductor

(29) 11 Movement mechanism

(30) 12 Actuating element

(31) 13 Actuator

(32) 14 Ceramic insulator

(33) 15 Interior

(34) 16 Capsule

(35) 17 Bellows

(36) 18 Arrow

(37) 19 Contact area

(38) 20 Shield

(39) 21 Connecting rod

(40) 22 Rotary bearing

(41) 23 Arrow

(42) 24 Guide

(43) 25 Arrow

(44) 26 Pair