Arrangement and method for guiding a switch rod of a high-voltage circuit breaker

Abstract

An arrangement for a high-voltage circuit breaker includes at least one movable electric contact piece of an interrupting unit. The at least one movable contact piece is disposed on a switch rod and the switch rod is movably mounted between an outer region and an inner region of the housing of the interrupting unit. The switch rod is guided in a solely linear manner in the arrangement. A method for driving the at least one movable electric contact piece includes using the switch rod to move the contact piece. The switch rod is moved in a solely linear manner along the longitudinal axis of the switch rod.

Claims

1. An anti-twist assembly for a high-voltage circuit breaker, the anti-twist assembly comprising: an interrupter unit including at least one movable electric contact piece, said interrupter unit having a housing supported by a supporting foot; a switch rod being movably mounted with an exclusively linear guidance of said switch rod, said at least one movable contact piece being disposed on said switch rod; and an anti-twist mechanism including a switch rod foot connected to said switch rod and providing said linear guidance of said switch rod, said anti-twist mechanism including a body connected to said switch rod foot and being movable in a groove formed in said supporting foot.

2. The anti-twist assembly according to claim 1, wherein said movable body has a cylindrical shape.

3. The anti-twist assembly according to claim 2, wherein said movable body is a screw.

4. The anti-twist assembly according to claim 1, wherein said interrupter unit is a vacuum interrupter unit in a vacuum tube.

5. The anti-twist assembly according to claim 4, wherein said vacuum interrupter unit includes at least one nominal current contact having two nominal current contact pieces and at least one arcing contact having two arcing contact pieces.

6. The anti-twist assembly according to claim 1, which further comprises at least one slide bearing disposed in a region of said linear guidance of said switch rod.

7. The anti-twist assembly according to claim 1, which further comprises a sealing element disposed between said switch rod and said housing, an inner region of said housing being gas-tightly sealed relative to an outer region of said housing by said switch rod and said sealing element.

8. The anti-twist assembly according to claim 7, wherein said sealing element is a bellows.

9. The anti-twist assembly according to claim 8, wherein said switch rod said bellows is disposed in a region of said switch rod foot.

10. The anti-twist assembly according to claim 9, which further comprises a concentrically disposed radial seal at least one of connecting or fastening and gas-tightly mechanically fixing said bellows to said switch rod foot.

11. The anti-twist assembly according to claim 6, wherein said switch rod foot is disposed at least one of concentrically in said supporting foot of said housing or concentrically relative to said slide bearing, and said switch rod is exclusively linearly movable along a longitudinal axis of said switch rod.

12. The anti-twist assembly according to claim 1, which further comprises a sliding sleeve spatially surrounding said switch rod, said sliding sleeve having a part rigidly mechanically connected to said switch rod in a region of said switch rod foot, for permitting a linear movement in a direction of a longitudinal axis of said switch rod in a cylindrical cutout formed in said supporting foot.

13. The anti-twist assembly according to claim 12, which further comprises a bellows disposed between said switch rod foot and said cylindrical cutout of said supporting foot for gas-tightly sealing an inner region of said housing relative to an outer region of said housing.

14. The anti-twist assembly according to claim 13, wherein said bellows is at least one of: gas-tightly fastened to said cylindrical cutout of said supporting foot on a side facing towards said interrupter unit, or gas-tightly fastened to said switch rod foot on a side facing away from said interrupter unit.

15. The anti-twist assembly according to claim 14, wherein said groove is formed on said side facing away from said interrupter unit.

16. The anti-twist assembly according to claim 1, which further comprises a coupling element disposed on one end of said switch rod in a region of said switch rod foot for coupling to at least one of a kinematic chain of the high-voltage circuit breaker or a gear or a drive.

17. A method for driving at least one movable electrical contact piece of a high-voltage circuit breaker, the method comprising the following steps: providing an interrupter unit having at least one movable contact piece and having a housing supported by a supporting foot; providing a switch rod having a longitudinal axis and being movably mounted with an exclusively linear guidance of the switch rod, the at least one movable contact piece being disposed on the switch rod; providing an anti-twist mechanism including a switch rod foot connected to the switch rod and providing the linear guidance of the switch rod, the anti-twist mechanism including a body connected to the switch rod foot and being movable in a groove formed in the supporting foot; and using the switch rod to move the at least one movable contact piece exclusively linearly along the longitudinal axis of the switch rod.

18. The method according to claim 17, which further comprises using a sealing element or a bellows to gas-tightly seal an evacuated inner region of the housing between the switch rod and the housing.

19. The method according to claim 17, which further comprises using the body to linearly guide the switch rod between an outer region and an inner region of the housing while preventing a twisting or rotation of the switch rod about the longitudinal axis of the switch rod.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 a schematic sectional illustration of an arrangement 1 for a high-voltage circuit breaker having a rotary transmission leadthrough through a housing 3 for driving a switch rod 2 according to the prior art; and

(2) FIG. 2 a schematic sectional illustration of an arrangement 1 according to the invention for a high-voltage circuit breaker having a switch rod 2 which is movably mounted between the outer region 5 and the inner region 4 of the housing 3, with an exclusively linear control; and

(3) FIG. 3 a schematic detail of a plan view from the underside of the arrangement 1 illustrated in FIG. 2.

DESCRIPTION OF THE INVENTION

(4) FIG. 1 shows a schematic sectional illustration of an arrangement 1 for a high-voltage circuit breaker according to the prior art for driving a movable electrical contact piece via a switch rod 2, having a rotary transmission lead through through the housing 3 of the high-voltage circuit breaker or an interrupter unit 15. The rotary transmission lead through comprises a rotary shaft 7 for transmitting a rotational movement from the outer region 5 into the inner region 4 of the housing 3 of the high-voltage circuit breaker and a rotary shaft having a packing seal 8 for the gas-tight sealing of the inner region 4 with respect to the outer region 5.

(5) A drive, for example a spring accumulator drive or an electric motor, provides movement energy for switching the high-voltage circuit breaker. The drive is not illustrated in the figures for the sake of simplicity. The movement energy is transmitted to one or more movable contact pieces via a kinematic chain in order to open or close the contacts of the interrupter unit. The high-voltage circuit breaker is thereby switched. The contact(s) with contact pieces are not illustrated in FIG. 1 for the sake of simplicity. For example, it is possible to include a nominal current contact with a movable contact piece and a fixed contact piece as an interrupter unit, or two movable contact pieces as a nominal current contact of the high-voltage circuit breaker. Alternatively, instead of only a nominal current contact, it is possible for the interrupter unit to comprise a nominal current contact and an arcing contact. Each contact can comprise a movable and a fixed contact piece, for example, or each can comprise two movable contact pieces.

(6) The movable contact piece(s) are mechanically connected to a switch rod 2 directly, in particular for a linear force effect, or indirectly, for example via a coupling gear, in particular for a force deflection. The switch rod 2 and the contact pieces of the contacts of the interrupter unit 15 are arranged in a housing 3. In the inner region 4, the housing is filled with a switching gas, e.g. SF.sub.6, in particular at a higher pressure than in the outer region 5. When using a vacuum interrupter unit in a vacuum tube, the region of the vacuum interrupter unit is evacuated.

(7) The switch rod 2, as part of the kinematic chain, is mechanically connected to a movable inner lever 9, which is mechanically connected to a movable outer lever 6 via the rotary shaft 7. The outer lever 6 is connected to the drive via a rod and/or a gear, for example. Analogously to the drive, the rod and the gear are not illustrated in the figures for the sake of simplicity. The movement energy during switching is transmitted from the drive to the movable contact piece(s) via the kinematic chain, in particular via the outer lever 6, the rotary shaft 7, the inner lever 9 and the switch rod 2. When closing the circuit, a movement by the switch rod is transmitted in direction 10; when opening the circuit, it is transmitted in the opposite direction. Thus, when closing the circuit, the contact pieces of a contact are moved towards one another and the electrical contact is closed. When opening the circuit, the contact pieces of a contact are moved away from one another and the electrical contact is opened.

(8) The movement transmitted by the rotary shaft 7 via the inner lever 9 to the switch rod 2, which converts a rotational movement into a longitudinal movement, generates a pendulum movement 11 of the switch rod 2, with a component in the perpendicular direction to the longitudinal axis of the switch rod 2. The longer the switch rod 2 in relation to the length of the inner lever 9, the smaller the component of the pendulum movement 11 with respect to the switching movement in direction 10 parallel to the center axis of the interrupter unit 15 of the housing 3.

(9) The housing 3 comprises a supporting foot 12, via which the housing 3 is fastened, for example, to a frame for positioning the high-voltage circuit breaker. A plurality of housings 3 of interrupter units and the drive and/or elements of the kinematic chain can be fastened to the frame. The interrupter unit 15 is arranged for example in a substantially cylindrical isolator housing, which is fastened in the lower region to the supporting foot 12 and held by this latter. A housing lower part 13, for example made from a cast iron material, closes the housing 3 in the lower region in a gas-tight manner. The rotary transmission leadthrough with the rotary shaft 7 and the rotary bearing with the packing seal 8 is arranged in the housing lower part 13 and connected to the switch rod 2 via the inner lever 9 in the region of the switch rod foot or at the lower end of the switch rod 2.

(10) The switch rod 2 with the contact(s) is therefore arranged completely in the inner region 4 of the gas-tight housing 3 and a pendulum movement 11 of the switch rod 2 has no influence on the gas-tightness of the interrupter unit or the housing 3 of the interrupter unit. The sealing effect is determined by the packing seal of the rotary bearing 8. A construction for high pressure differences of the inner region 4 with respect to the outer region 5 can be expensive and complex, or impossible from a certain pressure difference. Owing to the rotary transmission leadthrough, a large number of parts or elements are required in the kinematic chain, for example levers 6, 9 and shafts 7 with rotary bearing 8 and packing seal. This makes the construction complicated, expensive and material-intensive as well as heavy. The switch rod has to have a long length to minimize the influence of the pendulum movement 11 on the switching and the contact pieces. With frequent switching, the pendulum movement 11 can result in damage to the contact pieces, and only contact pieces with a special design can be used, in particular with a small contact area in relation to the contact piece length, or rounded contact pieces.

(11) To prevent the above-described disadvantages of the arrangement according to the prior art, in particular according to FIG. 1, an arrangement according to the invention comprises an exclusively linear control of the switch rod and prevents a pendulum movement of the switch rod 2. In FIG. 2, an arrangement 1 according to the invention is illustrated schematically in a sectional illustration, with a switch rod 2 which is movably mounted between the outer region 5 and the inner region 4 of the housing 3 and is guided exclusively linearly or executes an exclusively linear movement without a pendulum movement.

(12) An interrupter unit 15, in particular a vacuum interrupter unit, which comprises two contact pieces, is arranged in a housing 3. In the exemplary embodiment illustrated in FIG. 2, one contact piece is arranged in a fixed manner and one contact piece 14 is arranged in a movable manner; alternatively, both contact pieces can also be arranged in a movable manner. In addition to the nominal current contact pieces illustrated, nominal and arcing contact pieces can be included, which is not illustrated in the figures for the sake of simplicity.

(13) The movable contact piece 14 is fastened to the switch rod 2, in particular at one end of the switch rod 2, in the housing 3. With a movement for closing the circuit, the switch rod 2 is moved in direction 10, exclusively parallel to the longitudinal axis of the switch rod 2. With a movement for opening the circuit, the movable contact piece 14 is moved with the switch rod 2 in the opposite direction to direction 10.

(14) A coupling element 25 is arranged on the opposing side of the switch rod 2, opposite the side with the movable contact piece 14, on the end of the switch rod 2 outside the housing 3. The switch rod 2 is connected to further elements of the kinematic chain and the drive via the coupling element 25, which is not illustrated in the figures for the sake of simplicity. Via the coupling element 25, a movement which is provided by the drive is transmitted to the switch rod 2 in the direction 10 or in the opposite direction.

(15) In addition to an electrical isolator, in particular a substantially tubular isolator with ribs on the outside, for example, the housing 3 comprises a supporting foot 12, which is arranged at the lower end of the isolator and via which the, for example, tubular isolator is positioned vertically. The isolator is made for example from ceramic, a silicone material or a composite material. The supporting foot 12 is made for example from a metal, in particular cast iron or steel. The isolator is for example bonded or cast into the supporting foot 12 in a gas-tight manner. A continuous cutout 24 in the shape of a hollow tube or sleeve is formed in the supporting foot 12, in particular center-symmetrically about the center axis 26 of the supporting foot 12. The switch rod 2 is guided through the cutout 24, from the outer region 5 into the inner region 4 of the housing 3. The switch rod 2 is encompassed by a sliding sleeve 22 and enclosed in a gas-tight manner. The sliding sleeve 22 is designed in such a way that it moves in the cutout 24 of the supporting foot 12, along the longitudinal axis 26 of the switch rod 2 or the congruent center axis 26 of the supporting foot 12, upon a movement of the switch rod 2.

(16) A sealing element, in a particular a bellows 20, is arranged or mounted between the switch rod 2, or the sliding sleeve 22, and the cutout 24 in the supporting foot 12. The bellows 22, in conjunction with the switch rod 2, seals the cutout of the supporting foot 12 in a gas-tight manner and therefore delimits the inner region 4 of the housing 3 with respect to the outer region 5. The inner region 4 can be filled with a switching gas, e.g. SF.sub.6, or be at vacuum level, for example, i.e. evacuated. Fittings are also possible, with which the housing 2 is filled with an insulating gas, and/or an evacuated vacuum tube with the contact pieces of the interrupter unit 15 is arranged in the housing 2. As illustrated in FIG. 2, the bellows 20 can be fixedly connected to the switch rod 2 in a gas-tight manner at the switch rod foot 18 of the switch rod 2, i.e. at the lower end of the switch rod 2, in particular via a sealing flange 23. On the opposite side of a substantially cylindrical bellows 20, the bellows 20 can be fixedly connected to the cutout of the supporting foot 12 in a gas-tight manner, in particular at the end of the cutout towards the contact pieces.

(17) In the region of the switch rod foot 18, the switch rod 2 can be designed analogously to a piston and can move in the, in particular, substantially cylindrical cutout of the supporting foot 12, sealed by a radial seal 21 between the cutout 24 and the switch rod foot 18. Bodies 17 can be arranged in the switch rod foot 18, for example in the form of screws screwed into the switch rod foot 18 on opposite sides of a circumferential line of the switch rod foot 18, wherein the screw heads project radially out of the switch rod. These bodies 17 move with the switch rod 2 and can move in, in particular, linear grooves 16 or depressions in the cutout 24 of the supporting foot 12 or in the supporting foot 12 analogously to tram wheels in tram tracks. An anti-twist mechanism of the switch rod 2 is thus produced, i.e., as a result of the control, the switch rod is unable to rotate about its axis 26. At least one slide bearing 19 is arranged in the region of the linear control or guidance of the switch rod 2.

(18) A linear control of the switch rod 2 is produced as a result of the cylindrical sliding sleeve 22 and/or the cylindrical switch rod 2, which is movable in a cylindrical cutout in the supporting foot 12, in particular mounted towards the contact pieces on one side, and/or the linear control comprising the bodies 17 in the linear grooves 16, in particular arranged on the side remote from the contact pieces. The movement of the switch rod 2 takes place exclusively in direction 10 or in the opposite direction along the longitudinal axis 26 of the switch rod 2, without a pendulum movement. The anti-twist mechanism prevents twisting of the switch rod 2 during the movement. The seal in the form of a bellows 20 is thus only loaded in the longitudinal direction of the bellows 20, which ensures good gas-tight sealing of the inner region 4 with respect to the outer region 5 of the housing 3 which is stable in the long term.

(19) A detail of a plan view of the underside of the arrangement 1 illustrated in FIG. 2 is illustrated schematically in FIG. 3. The coupling element 25 at the lower end of the switch rod 2, for coupling elements of the kinematic chain towards the drive, is arranged on the base area of the cylindrical switch rod 2 or the cylindrical switch rod foot 18. The substantially cylindrical switch rod foot 18, designed analogously to a piston in an internal combustion engine, is arranged with mechanical fit in the cylindrical cutout in the supporting foot 12, and an anti-twist mechanism, comprising the bodies 17 movably arranged in the grooves 16, prevents a rotational movement of the switch rod 2 about its longitudinal axis 26. During the switching of the high-voltage circuit breaker, the switch rod 2 executes an exclusively linear movement perpendicularly to the plane of the drawing in FIG. 3; into the plane of the drawing for closing the circuit and out of the plane of the drawing for opening the circuit. Pendulum movements of the switch rod 2, with movement components in a direction parallel to the plane of the drawing, are suppressed or impossible as a result of the linear control or bearing of the switch rod 2 in the cutout 24 of the supporting foot 12.

(20) The exemplary embodiments described above can be combined with one another and/or can be combined with the prior art.

LIST OF REFERENCE SIGNS

(21) 1 Arrangement for a high-voltage circuit breaker 2 Switch rod 3 Housing 4 Inner region 5 Outer region 6 Outer lever 7 Rotary shaft 8 Rotary bearing with packing seal 9 Inner lever 10 Movement direction along the longitudinal direction of the switch rod 11 Pendulum movement of the switch rod 12 Supporting foot 13 Housing lower part with lead through for elements of the kinematic chain 14 Movable contact piece 15 Interrupter unit 16 Groove 17 Body 18 Switch rod foot 19 Slide bearing 20 Bellows 21 Radial seal 22 Sliding sleeve 23 Sealing flange of the bellows 24 Cylindrical cutout 25 Coupling element 26 Longitudinal axis of the switch rod