EP2018647B1 - Circuit breaker - Google Patents

Description

The invention relates to a circuit breaker having a rated current contact arrangement, which has a nominal current contact and a rated current countercontact arranged movably relative to each other, as well as with an arcing contact arrangement, which arranged relative to each other movably having an arcing contact and an arc countercontact.

From the US 4, 538, 039 a circuit breaker is known, which has a designed as a pencil rated current contact of a rated current switch and a parallel to the rated current switch vacuum switch as arcing contact arrangement. The from the US 4, 538, 039 known circuit breaker has a kinematics, which is connected to the rated current switch and the vacuum switch such that when you turn off the rated current switch is first disconnected and then the time following the vacuum switch is disconnected. When switching on this circuit breaker first the nominal current switch is closed and then closed the vacuum switch.

The object underlying the invention is to provide a comparison with the cited prior art, as in US 5, 952, 635 described to provide advantageous power switch.

This object is achieved by a circuit breaker according to claim 1. The dependent claims contain advantageous embodiments of the invention.

A circuit breaker according to the invention comprises a rated current contact arrangement having a rated current contact and a rated current countercontact relative to one another, and an arcing contact arrangement having an arcing contact and an arc counter contact arranged movably relative to one another. In addition, it comprises a kinematics which can be driven via an actuator. The kinematics comprises a first lever which is at least indirectly connected to the actuating member and which is rotatably mounted about a switching rotational point and is connected at least indirectly to the rated current contact for moving it. In addition, it comprises a second lever at least indirectly connected to the actuator, which is rotatably mounted both about a first displaceable pivot point and about a second displaceable pivot point. This lever is at least indirectly connected in the region of the first pivot point with the arc contact for moving the same by a displacement of the first pivot point. In the region of the second pivot point, the second lever acts on displacement on a spring element. The spring element is configured such that it opposes a displacement of the second pivot point a predetermined force which is greater than the force to be applied for displacing the first pivot point to contact between the arc contact and the arc counter contact. In the circuit breaker according to the invention, the arcing contact arrangement can be designed in particular as a vacuum contact with a switching pole as an arcing contact and a counter pole as an arc countercontact.

In the circuit breaker according to the invention, the kinematics allow, in response to a turn-off movement of the actuator, first a separation of the rated current contact from the rated current counter contact before a separation the arc contact is made by the arc counter contact. At the same time, it allows an electrical connection of the arcing contact to the arc counter contact to be established first, in response to a switch-on movement of the actuator, before establishing an electrical connection of the rated current contact to the rated current counter contact. With the help of the second lever with the first and second fulcrum and with the help of the spring element, namely, a movement can be realized in which at a switch-on movement of the actuator first learn both the arcing contact and the rated current contact a lifting movement. After the arcing contact has traveled a stroke that results in a contact, resistance to further movement of the arcing contact increases in the same direction. If the spring element is biased so that the spring force, which counteracts a displacement of the second pivot point is less than the resistance to further movement of the arcing contact, there is now instead of a further displacement of the first pivot point to a displacement of the second pivot point against the spring force , As a result of this, when the starting movement of the actuating member continues, there is no further lifting movement of the arcing contact, but a further lifting movement of the rated current contact. Thus, when the necessary to close the arc contact stroke is designed to be smaller than the necessary to close the rated current contact stroke, the arc contact closes at a power-up before the rated current contact. In a turn-off movement of the actuator, the movement is reversed, so that the rated current contact separates before the arcing contact. For this purpose, the first lever may be part of a first lever string and the second lever may be part of a second lever string. The lever strands each include the switching pivot as one Fulcrum and are connected to the actuator on the one hand and the rated current contact or the arc contact on the other. They are coordinated so that the stroke of the first lever string is greater than the stroke of the first pivot point in its displacement.

The arcing contact arrangement can be designed as a vacuum switch with a switching pole as an arcing contact and a counter pole as an arc countercontact. The switching pole and the opposite pole can be designed in particular as impact contacts, i. they have baffles which abut each other for producing an electrical contact and thus oppose a further lifting movement of the arcing contact, ie the Schaltpos, a very high resistance, which are limited only by the mechanical stability of the vacuum switch. In addition, the switching pressure of the baffles can be increased by the further tensioning of the spring element during displacement of the second pivot point, which increases the reliability of the contact. The switching pole and opposite pole of the vacuum switch can advantageously contain sintered materials with copper and / or chromium.

The switching sequence in the circuit breaker according to the invention is advantageous over other switching sequences. When switched off, the breaking current commutates from the rated current contact to the arcing contact. Thus, the arc produced when high currents are turned off burns between the arcing contacts and when using a vacuum contact as arcing contact in the vacuum chamber of the vacuum tube. Due to the material of the arcing contacts, the special geometry of the arcing contacts and possibly the vacuum high currents can be switched on or off. A melting of the arcing contacts can be caused by materials with high Melting temperatures are counteracted. In vacuum, oxidation and thus burning off of the contacts is also avoided. When switching on, a flashover occurs, ie an arc which occurs shortly before the final closing of the contacts, between the arc contacts, where it is easy to control. In particular, when using a vacuum contact as arcing contact he is well controlled in the vacuum tube. In the further course of the closing movement then closes the rated current contact and the current commutated by the arcing contact to the rated current contact. Both the arc resulting when switching off as well as the flashover occur between the arc contacts, where they are easy to control, especially when using a vacuum contact.

As a spring element of the circuit breaker according to the invention is, for example, a compression spring which is arranged between the second lever in the region of the second pivot point and an abutment, for example. A spring plate. The circuit breaker may also have a spring guide and a relative to the spring guide displaceable and the abutment opposite spring bearing, which acts on the second lever at a displacement of the second pivot point such that a tensioning of the spring takes place. If the abutment along the spring guide is designed displaceable and fixable, can be changed by moving the abutment of the stroke for the displacement of the second pivot point and thus also the stroke for the switching movement of the arcing contact.

The circuit breaker according to the invention can be configured such that the actuating member is connected via a tab articulated to the second lever, so that one in the spring element stored spring energy can not or only partially react on the actuator.

In one embodiment of the circuit breaker according to the invention the rated current contact is at least partially formed as a hollow cylinder and the arcing contact is at least partially in particular radially centered, disposed within the rated current contact, so that a switching movement of the rated current contact can be made coaxial with a switching movement of the arcing contact. By this configuration, a rectified movement of both the rated current contact and the arcing contact of the circuit breaker can be done without these interfere with each other. As an alternative to a cylindrical rated current contact, other geometric shapes of a rated current contact and a nominal current counter contact designed correspondingly to the rated current contact are also conceivable.

• Figur 1 zeigt - schematisch - ein Ausführungsbeispiel für einen Leistungsschalter mit einem Vakuumschalter und einem zu dem Vakuumschalter elektrisch parallel geschalteten Nennstromschalter;
• Figur 2 zeigt - schematisch - den in Figur 1 dargestellten Leistungsschalter in eingeschaltetem Zustand;
• Figur 3 zeigt - schematisch - den in Figur 1 dargestellten Leistungsschalter in ausgeschaltetem Zustand;
• Figur 4 zeigt - schematisch - ein Ausführungsbeispiel für einen Kontaktdruckfederspeicher mit einer Kontaktdruckfeder.

Further features, properties and advantages of the present invention will become apparent from the following description of an embodiment with reference to the accompanying figures.

• FIG. 1 shows - schematically - an embodiment of a circuit breaker with a vacuum switch and to the vacuum switch electrically connected in parallel rated current switch;
• FIG. 2 shows - schematically - the in FIG. 1 shown circuit breaker in the on state;
• FIG. 3 shows - schematically - the in FIG. 1 shown circuit breaker in off state;
• FIG. 4 shows - schematically - an embodiment of a contact pressure spring accumulator with a contact pressure spring.

FIG. 1 schematically shows an embodiment of a circuit breaker 1. The circuit breaker 1 has a formed as Vakuumsehalter 2 arcing contact arrangement with a fixedly arranged in this embodiment opposite pole 4 and a movable along a longitudinal axis 40 switching pole 6. The circuit breaker 1 also has a rated current switch electrically connected in parallel with the vacuum switch 2. The rated current switch comprises a rated current contact 8 and a rated current counter contact 10.

The rated current contact 8 is formed as a hollow cylinder. In the cylindrically enclosed cavity of the rated current contact 8, the vacuum switch 2, which extends parallel to the longitudinal axis 40, is arranged radially centered-in a cross-sectional plane running perpendicular to the longitudinal axis 40.

The switching pole 6 is designed to be movable along the longitudinal axis 40. The switching pole 6 and the opposite pole 4 each have a button provided for electrical contact, wherein the buttons are each arranged perpendicular to the longitudinal axis 40 and to each other plane-parallel. The switching pole 6 and the opposite pole 4 are jointly surrounded by an evacuated space, which is enclosed by a vacuum housing 5.

The circuit breaker 1 has a kinematics which is at least indirectly connected to the switching pole 6 and at least indirectly connected to the rated current contact 8. The kinematics also has a shift lever 12 with an angled region, wherein in the region of a vertex of the angle thus formed, a central pivot shaft 13 is arranged, so that the shift lever 12 is pivotable about the central pivot shaft 13. A pivot axis formed by the pivot shaft is perpendicular to the longitudinal axis 40 of the circuit breaker. The central pivot shaft 13 also passes through a fastening tab 15, which can be fixed on a housing facing away from the central pivot shaft 13 movable on a housing. The shift lever 12 is connected via the pivot shaft 13 with a shaft 11, wherein the shaft 11 extends parallel to the longitudinal axis 40. The pivot shaft 13 passes through the shaft 11 in the region of a shaft end of the shaft 11, so that the shaft 11 is pivotable about an axis formed by the pivot shaft 13.

The shaft 11 passes through a wall in the region of a - not shown in this figure - opening the vacuum housing 5 and is connected within the vacuum housing 5 with the switching pole 6. The shift lever 12 is connected to the input end side in the region of one end via a hinge 16 with the tab 14. The tab 14 is pivotally connected to an actuating member 18 in the region of an end facing away from the hinge 16. The actuator 18 is formed as a substantially triangular plate, wherein in the region of a triangle apex a switch shaft 22 is arranged perpendicular to a triangle plate plane, so that the triangular plate can pivot about the switch shaft 22. The actuator 18 is movably connected to the tab 14 in the region of a triangle leg tip. The actuating member 18 is connected to a shift rod 20 in the region of one of the triangle leg tips opposite the lug 14. The Shift rod 20 may be driven, for example by a hydraulic, a spring-loaded or Kinoymatik or a comparable drive device.

The switch shaft 22 is rigidly connected to a lever 24, wherein the lever 24 extends perpendicular to the shaft axis of the switch shaft 22 and thus upon rotation of the switch shaft 22 by the actuator 18 can be pivoted about the pivot axis formed by the switch shaft 22.

The lever 24 is pivotally connected at one end facing away from the switch shaft 22 with a tab end of a tab 26, wherein the tab 26 in the region of an end facing away from the pivotally connected to the lever 24 via a pivot shaft 27 and via a connecting piece a formed on the rated current contact 8, radially inwardly extending rib 29 is coupled, and thus effectively coupled to the rated current contact 8:

A pivot axis formed by the pivot shaft 27 extends perpendicular to the longitudinal axis 40 of the circuit breaker first

When moving the shift rod 20 thus the rated current contact - driven by the actuator 18, the lever 24, and the tab 26 - parallel to the longitudinal axis 40 of the circuit breaker 1 are reciprocated.

The shift lever 12 is pivotally connected in the region of an end facing away from the hinge 16 with a - in this embodiment, ball-mounted - outer pivot shaft 36. The pivot shaft 36 is connected to a spring guide 30 and extends through a slot-shaped opening of the spring guide 30. The spring guide 30 is arranged parallel to the longitudinal axis 40 and within a circumferentially coiled about the spring guide 30 switching pressure spring 28.

The switching pressure spring 28 is secured in the region of its end facing the lever 12 by a longitudinal spring guide movable spring plate 34. At its end facing away from the first spring plate 34, it is secured by a second spring plate 35. The second spring plate 35 is slidably connected to the spring guide 30 and fixed, whereas the spring plate 34 is arranged parallel to the longitudinal axis 40 on the spring guide 30 slidably.

In the area of outer ends of the shaft 36, two wheels 37 are arranged, wherein an end face of the first spring plate 34, driven by a bias of the contact pressure spring 28, against one of the end face of the first spring plate 34 facing the circumferential point of the arranged on the shaft 36 wheels 37 presses. The spring force of the switching pressure spring 28 thus acts perpendicular to the pivot shaft 36th

The spring force of the switching compression spring 28 thus acts also on the shift lever 12 on the pivot shaft 13, and thus acts proportionally - according to a parallelogram of forces - along the longitudinal axis 40 on the shaft 11 and perpendicular to a Schaltpolfläche the switching pole 6. The switching pole 6 is in this way operatively connected to the switching pressure spring 28.

According to the parallelogram of forces described above, a part of the spring force generated by the switching compression spring 28 also tries to react on the actuating member 18 via the shift lever 12 and the lug 14. This reaction is, however, prevented by the fact that the shift lever 12th and the tab 14 and the hinge 16 formed swivel articulated in the region of the pivot joint 16 and thus can not - or only partially act back on the actuator 18.

FIG. 2 shows a switch on in FIG. 1 shown circuit breaker 1.

The switching rod 20 can be moved to turn on the circuit breaker 1 in the direction 21. The actuator 18 pivots about the switch shaft 22 and moves over the lever 24, the tab 26 and the pivot shaft 27 the rated current contact 8 parallel to the longitudinal axis 40. At the same time when switching on the described movement of the rated current contact 8 of the switching pole 6 of the vacuum switch 2 on the Switch shaft 22, the tab 14, the lever 12 and the shaft 11 driven. The shaft 11 and the switching pole 6 connected to the shaft 11 are thus moved parallel to the longitudinal axis 40. The shift lever 12 is rotated by the actuating member 18 about the ball-bearing outer pivot shaft 36 at power. When the shift rod 20 has covered about half of a total intended stroke, the switching pole 6 of the vacuum switch 2 touches the stationary arranged mating contact 4 of the vacuum switch 2. The vacuum switch 2 is now electrically closed.

In the course of a switching movement caused by the shift rod 20, the shift lever 12 is rotated about the central pivot shaft 13. By acting on the shift rod 20 force is now over the pivot shaft 36 and the spring plate 34, the compression coil spring 28 is compressed and thus spring energy stored in the switching pressure spring 28.

The opposite pole 4 of the vacuum switch 2 and the switching pole 6 of the vacuum switch 2 are now pressed together by the spring force of the contact pressure spring 28 as well as by the force acting on the shift rod 20 force parallel to the longitudinal axis 40.

In the illustrated embodiment of the circuit breaker 1, the stroke of the switching pole 6 of the vacuum switch 2 is formed changeable. For this purpose, the second spring plate 35 is connected to a parallel to the longitudinal axis 40 extending shift rod, which is formed in the present embodiment as eye bolt 32 and extends through an opening of a fixedly arranged angle 31. The eye bolt can be fixed in its position along the longitudinal axis 40 by means of a fixing means, for example two fixing nuts (not shown in this figure). To fix the eye screw 32, and thus the position of the immovably connected to it in the axial direction second spring plate 35, by means of the two nuts, one of which is located on each side of the angle relative to the spring guide 30.

When the eyebolt 32 is moved away from the spring plate 34 parallel to the longitudinal axis 40, then the switching lever 12 is moved via the spring guide 30 and thus the stroke of the switching pole 6 is increased.

FIG. 3 shows a switch off in FIG. 1 and 2 shown circuit breaker 1.

Switching off the circuit breaker 1 is effected by a switch-off movement of the shift rod 20 in the Ausschichttrichtung 19. As a result, the rated current contact 8 undergoes a switch-off movement, while at the same time a relaxation of the compression spring 28 by turning the lever 12 about the central pivot shaft 13 takes place. Only when the compression spring is relaxed enough, the lever 12 begins to rotate about the outer pivot shaft 36 so that a switch-off movement of the switching pole 6 is brought about. In the switch-off movement, therefore, a separation of the switching pole 6 of the opposite pole 4 of the vacuum switch 2 - driven by the actuator 18, via the tab 14, the shift lever 12 and the shaft 11 - effected in time after a separation of the rated current contact 8 of the Nennstromgegenkontakt 10.

An opening of the vacuum switch 2 is thus temporally after opening the rated current switch, formed by the rated current contact 8 and the Nennstromgegenkontakt 10, causes. The rated current mating contact 10 is shown here only in sections. In an exemplary embodiment (not shown here), the rated current mating contact 10 is designed as an annular sliding contact encompassing the rated current contact 8.

FIG. 4 shows an exemplary embodiment of a contact pressure spring accumulator 33, formed by the contact pressure spring 28, the spring plate 34, the spring plate 35, the eye bolt 32, and the spring guide 30th

The spring guide 30 has in the region of an end remote from the spring plate 35 an end designed as a breakthrough slot 38. Through this slot 38 is in FIG. 1 the pivot shaft 36 performed.

Shown is also a wheel 37 with an opening for passing through a shaft, through the breakthrough of the pivot shaft 36 extends. The wheel 37 is provided for supporting against the spring plate 34.

LIST OF REFERENCE NUMBERS

1

breakers

2

vacuum switch

4

antithesis

5

vacuum housing

6

switching pole

8th

Current Rating Contact

10

Rated current mating contact

11

shaft

12

gear lever

13

pivot shaft

14

flap

15

mounting tab

16

joint

18

actuator

19

the disconnection

20

shift rod

21

switching-on

22

switch shaft

24

lever

26

flap

27

pivot shaft

28

Switching pressure spring

29

groove

30

leadership

31

angle

32

eyebolt

33

Contact pressure spring

34

spring plate

35

spring plate

36

camp

37

wheel

38

Long hole

Claims (8)

1. Circuit breaker (1) with

   - a rated current contact arrangement (8, 10), which has, arranged movably relative to one another, a rated current contact (8) and a rated current mating contact (10),

   - an arcing contact arrangement (2), which has, arranged movably relative to one another, an arcing contact (6) and an arcing mating contact (4), and

   - kinematics, which are capable of being driven via an actuating element (18) and are operatively connected to the rated current contact (8) and the arcing contact (6),

   characterized in that the kinematics comprise:

   - a first lever (24), which is connected at least indirectly to the actuating element (18), is mounted rotatably about a switching fulcrum (22) and is connected at least indirectly to the rated current contact (8) for the movement thereof,

   - a second lever (12), which is connected at least indirectly to the actuating element (18) and is mounted rotatably both about a first displaceable fulcrum (13) and about a second displaceable fulcrum (36), the lever (12) being connected at least indirectly in the region of the first fulcrum (13) to the arcing contact (6) for the movement thereof by means of a displacement of the first fulcrum (13), and

   - a spring element (28), on which the second lever (12) acts in the region of the second fulcrum (36) during displacement and which is configured in such a way that it counteracts a displacement of the second fulcrum (36) with a predetermined force, which is greater than the force which needs to be applied in order to displace the first fulcrum (13) until contact is produced between the arcing contact (6) and the arcing mating contact (4).
2. Circuit breaker according to Claim 1, characterized in that the arcing contact arrangement is in the form of a vacuum interrupter (2) with a switching pole (6) as the arcing contact and a mating pole (4) as the arcing mating contact.
3. Circuit breaker according to Claim 2, characterized in that the switching pole (6) and/or the rated current contact (8) are in the form of an electrical impact contact.
4. Circuit breaker (1) according to Claim 3, characterized in that the first lever (24) is part of a first lever train, and the second lever (12) is part of a second lever train, the lever trains each comprising the switching fulcrum (22) as a fulcrum and being connected firstly to the actuating element and secondly to the rated current contact (8) or the arcing contact (6), and in that the lever trains are matched to one another in such a way that the excursion of the first lever train is greater than the excursion of the first fulcrum (13) during its displacement.
5. Circuit breaker (1) according to one of Claims 1 to 4, characterized in that the spring element is a compression spring (28), which is arranged between the second lever (12) in the region of the second fulcrum (36) and an abutment (35).
6. Circuit breaker according to Claim 5, characterized by a spring guide (30) and a spring bearing (34), which is capable of being displaced with respect to the spring guide (30) and is arranged opposite the abutment (35) and on which the second lever (12) acts in the event of a displacement of the second fulcrum (36) in such a way that tensioning of the spring (28) takes place, the abutment (35) being configured so as to be capable of being displaced and fixed along the spring guide (30).
7. Circuit breaker (1) according to one of Claims 1 to 6, characterized in that the actuating element (18) is connected in articulated fashion to the second lever (12) via a lug (14).
8. Circuit breaker (1) according to one of Claims 1 to 7, characterized in that the rated current contact (8) is shaped at least partially in the form of a hollow cylinder, and the arcing contact arrangement (2) is arranged at least partially in particular radially centrically within the rated current contact (8) in such a way that a switching movement of the rated current contact (8) takes place coaxially with respect to a switching movement of the arcing contact (6) of the arcing contact arrangement (2).

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