Arrangement and method for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker

Abstract

In an arrangement and a method for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker, an actuating rod forms an element of a kinematic chain of the high-voltage circuit breaker. A lever element can rotate about an axis and can be mechanically connected to a drive via a connection element. A coupling element is configured to mechanically movably couple the actuating rod and the lever element. The actuating rod and the coupling element each have a longitudinal axis. The longitudinal axes are situated substantially on a common axis at a point in time when a separating action of the vacuum interrupter occurs.

Claims

1. An arrangement for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker, the arrangement comprising: a switching rod forming an element of a kinematic chain of the high-voltage circuit breaker, said switching rod having a longitudinal axis; a lever element rotatably mounted about an axis and configured to be mechanically connected to a drive by way of a connecting element; a coupling element configured to mechanically movably connect said switching rod with said lever element, said coupling element having a longitudinal axis; said switching rod having a circular-cylindrical shape, with a cuboidal end movably fastened to said coupling element; said longitudinal axis of said switching rod and said longitudinal axis of said coupling element being oriented substantially on a common axis at a moment in time at which a separating action of the vacuum interrupter takes place.

2. The arrangement according to claim 1, wherein an angle between the longitudinal axis of said switching rod and the longitudinal axis of said coupling element is precisely zero degrees at the moment in time when the separating action takes place.

3. The arrangement according to claim 1, further comprising a housing and a guide for guiding a movement of said switching rod in said housing.

4. The arrangement according to claim 3, wherein said housing is a hollow-cylindrical housing with a circular base area, and said guide is configured to guide said switching rod along a linear movement path.

5. The arrangement according to claim 1, wherein said coupling element has a cuboidal bar shape.

6. The arrangement according to claim 1, wherein said coupling element has a first end rotatably fastened to said switching rod by way of a fastening element and an opposite end rotatably fastened to said lever element by way of a fastening element.

7. The arrangement according to claim 6, wherein said fastening element connecting said first end and said opposite end of said coupling element is a bolt or a screw.

8. The arrangement according to claim 1, wherein said lever element is rotatably mounted about a central axis in a bearing block, and/or said lever element is movably fastened to said bearing block by way of a fastening element.

9. The arrangement according to claim 8, wherein said fastening element is a bolt or a screw.

10. The arrangement according to claim 1, wherein said lever element has two lever arms, and said connecting element for connecting to the drive is fastened to one end of one of said two lever arms.

11. The arrangement according to claim 1, wherein the axis about which said lever element is rotatably mounted is arranged in a center of said lever element, and/or said coupling element is movably fastened to said lever element in the center of said lever element.

12. The arrangement according to claim 1, wherein the common axis of said switching rod and of said coupling element is parallel to a direction of a drive movement of said connecting element at the time at which the separating action of the vacuum interrupter takes place.

13. The arrangement according to claim 1, wherein the common axis of said switching rod and of said coupling element is perpendicular to a direction of a drive movement of said connecting element at the time at which the separating action of the vacuum interrupter takes place.

14. A method for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker, the method comprising: providing a switching rod with a circular-cylindrical shape, and a cuboidal end movably fastened to a coupling element; moving a connecting element by a drive and thereby moving a lever element which is rotatable about an axis and which thereby transmits mechanical kinetic energy to the switching rod by way of the coupling element; transmitting with the switching rod, which forms a member of a kinematic chain of the high-voltage circuit breaker, kinetic energy to an electrical contact of the vacuum interrupter during switching; and aligning a longitudinal axis of the switching rod and a longitudinal axis of the coupling element to substantially form a common axis at a time at which a separating action of the vacuum interrupter takes place.

15. The method according to claim 14, which comprises providing the arrangement according to claim 1, and carrying out the method with the arrangement.

16. The method according to claim 14, wherein the longitudinal axes of the switching rod and of the coupling element enclose an angle of less than five degrees at the time at which the separating action of the vacuum interrupter takes place.

17. The method according to claim 14, wherein a force perpendicular to the longitudinal axis of the switching rod on the switching rod is equal to zero at the time at which the separating action of the vacuum interrupter takes place.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIGURE schematically shows a sectional view through an arrangement 1 according to the invention for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker at the time at which a separating action of the vacuum interrupter takes place.

DETAILED DESCRIPTION OF THE INVENTION

(2) The FIGURE schematically shows a sectional view through an arrangement 1 according to the invention for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker. The FIGURE shows the arrangement 1 at the time at which a separating action of the vacuum interrupter takes place. A switching rod 7 is movably mounted in a housing 10, in a manner linearly guided by means of a guide 9 by way of one end of the switching rod 7. The switching rod 7 is designed to transmit kinetic energy from a drive of the high-voltage circuit breaker to a movable contact piece of the vacuum interrupter during switching.

(3) During switch off, that is to say when the current path is isolated by means of the vacuum interrupter or by means of the contact of the vacuum interrupter, in particular with a movable and a fixed contact piece, the contact pieces of the vacuum interrupter are pressed against one another at the beginning. The contact pieces can be welded to one another during switch on, in particular by the action of an arc. A large amount of force is required at the beginning of the switch off process, that is to say a separating action, in order to reliably separate the contact pieces from one another. The kinetic energy or the force for a separating action and the further movement of the movable contact piece are provided by the drive and transmitted to the movable contact piece by means of elements of a kinematic chain. The movement profile, in particular the profile of the force on the movable contact piece with respect to time, is determined, among other things, by the drive and the elements of the kinematic chain. At the beginning of the switch off process, during the separating action, the force to be applied is at a maximum.

(4) For low-loss transmission of the kinetic energy from the drive to the movable contact piece with a predetermined movement profile, the kinetic energy is transmitted from the drive, by means of a connecting element 6, to a lever element 3 which is mounted in a rotatable manner about an axis 4. The lever element 3 is mechanically connected to the switching rod 7 in a movable manner by means of a coupling element 5. The kinetic energy of the drive, for example of a stored-energy spring mechanism, is transmitted from the drive, by means of the connecting element 6, as a linear movement to the lever element 3, by a rotational movement of the lever element 3 about the axis 4 to the coupling element 5 which is fastened to the lever element 3 and which is rotatably mounted at each of its ends and, by way of one end, is fastened in a movable manner to the lever element 3, and the kinetic energy is transmitted from the coupling element 5 to the switching rod 7 which, at one end, is movably connected to one end of the coupling element 5. The movement of the switching rod 7 is linear owing to the guide 9 in the housing 10, and is transmitted to the movable contact piece of the vacuum interrupter in a linear manner, that is to say with a direction along a straight line, for switching purposes.

(5) The housing 10 is of, for example, tubular design, in particular of hollow-cylindrical design with a circular base area and top area. The switching rod 7 is of, for example, rod-like design, in particular cylindrical design, with a flattened, in particular cuboidal, end. A guide 9, which is designed, for example, in the form of a sliding ring composed of, for example, Teflon in an annular integrally formed portion with a groove on the switching rod 7, is arranged in the housing 10 in an annular manner around the circumference of the cylindrical part of the switching rod. The guide 9 slides, in the event of a linear movement of the switching rod along the longitudinal axis of the switching rod, along the inner wall of the housing 10. The housing 10 has a longitudinal axis which is coaxial to the longitudinal axis of the switching rod 7.

(6) The coupling element 5 is of cuboidal, elongate design, in particular with four beveled or rounded edges. The coupling element 5 is fastened, at one end, in a rotatable manner to the flattened, in particular cuboidal, end of the switching rod 7 by way of a fastening element, in particular a bolt or a screw, with one side of the cuboidal end of the switching rod 7 plane-parallel to one side of the cuboidal coupling element 5. The coupling element 5 is rotatably fastened, at the opposite end, to the lever element 3 by way of a fastening element, in particular a bolt or a screw, with a flat side of the lever element 3 plane-parallel to one side of the cuboidal coupling element 5. The longitudinal axis of the coupling element 5 is on a common axis 8 with the longitudinal axis of the switching rod 7, analogously to a coaxial arrangement of the longitudinal axes, at the time at which the separating action takes place, as is illustrated in the FIGURE.

(7) As a result, the force or the movement is transmitted from the drive by the coupling element 5 in a linear manner along the axis 8 to the switching rod 7 at the time at which the separating action takes place, when the force is at a maximum. No transverse components to the axis 8 of the force are transmitted. A movement at the time at which the separating action takes place is performed exclusively in the direction along the axis 8, as a result of which the guide 9 is not loaded in the direction of the housing 10, an oscillating or vibrating movement of the switching rod 7 is avoided, and losses in kinetic energy due to movement components perpendicular to the axis 8 are suppressed. Therefore, a reliable switching movement, in particular without tilting of the switching rod 7, is possible in the housing 10 at the time at which the separating action takes place, with minimal expenditure of force or energy, as a result of which the drive and components of the kinematic chain can be designed to be correspondingly small, this saving costs and energy.

(8) The lever element 3 is rotatably fixed in a mechanically stable manner to a bearing block 2 by means of a fastening means, in particular a bolt or a screw. The bearing block 2 and the housing 10 are fastened, for example screwed or welded, to a supporting frame of the high-voltage circuit breaker for example. The vacuum interrupter and the housing 10 are comprised, for example, by an insulator which can likewise be fastened to the supporting frame, for example in an upright manner as a pillar on the supporting frame, this not being illustrated in the FIGURE for reasons of simplicity.

(9) The lever element 3 is designed, for example, as a parallelepiped with rounded edges. Grooves can be made in the body of the lever element 3, wherein one end of the coupling element 5 can be arranged in a manner pushed into a groove. As an alternative, the coupling element 5 can be arranged on and rotatably fastened to the outside of one side of the lever element 3. Bores can be made in the lever element 3 adjacent to the two opposite edges of the lever element 3, as is shown in the FIGURE, wherein the coupling element 5 is fastened by means of the fastening means and a bore. Opposite to this, the lever element 2 is fastened to and rotatably mounted on the bearing block 2 by means of the second bore and a fastening means.

(10) A bore can be made in the lever element 3 adjacent to a further edge of the lever element 3, as is shown in the FIGURE, wherein the connecting element 6 to the drive is fastened by means of a fastening means and the bore. The three bores in the lever element 3 form a triangle in a plan view of the lever element 3, as is shown in the FIGURE. In a drive which is arranged vertically in relation to the bearing block 2 or adjacent along the axis 8, that is to say below the bearing block 2 in the FIGURE, the connecting element 6 is arranged at or rotatably fastened to the bore, in particular, of the right-hand corner of the lever element 3 in accordance with the FIGURE. The force or movement direction 11 of the connecting element 6 during a switching movement is parallel to the axis 8 on which the longitudinal axes of the switching rod 7 and of the coupling element 5 lie at the time at which the separating action takes place.

(11) In a drive which is arranged horizontally in relation to the bearing block 2 or adjacent perpendicular to the axis 8, that is to say in particular on the left next to the bearing block 2 in the FIGURE, the connecting element 12 is arranged at or rotatably fastened to the bore of, in particular, the left-hand corner of the lever element 3 in accordance with the FIGURE. The force or movement direction of the connecting element 12 during a switching movement is perpendicular to the axis 8 on which the longitudinal axes of the switching rod 7 and of the coupling element 5 lie at the time at which the separating action takes place.

(12) The above-described exemplary embodiments can be combined with one another and/or can be combined with the prior art. Therefore, for example, all elements or parts of the arrangement 1 in the FIGURE can be composed of metal, in particular steel, cast iron and/or copper. The guide can have a sliding ring composed of, for example, Teflon, plastic and/or rubber. The housing 10 can be comprised by an insulator in which the vacuum interrupter is arranged, in each case sealed off in a gas-tight manner in the region of the switching rod 7 by means of a set of bellows. The insulator can, for example, be composed of silicone, ceramic and/or a composite material. In this case, the housing 10 can be arranged in the insulator, for example as a metal pipe. As an alternative, the housing 10 can be part of the insulator. The end of the switching rod 7 can be designed as a cuboid or in a circular-cylindrical manner, wherein a groove can be made in the end, the coupling element being pushed into said groove in a movable manner and being fastened in a rotatable manner to the switching rod 7. The lever element 3 can be designed, for example, as a parallelepiped or as a prism with a triangular base area, in particular with rounded edges.

LIST OF REFERENCE SIGNS

(13) 1 Arrangement for driving a movable contact of a vacuum interrupter in a high-voltage circuit breaker 2 Bearing block 3 Lever element 4 Axis on the lever element 5 Coupling element for the switching rod 6 Connecting element for the drive parallel to the coaxial axis 7 Switching rod 8 Coaxial axis of the coupling element and of the switching rod at the time at which a separating action of the vacuum interrupter takes place 9 Guide of the switching rod 10 Housing 11 Drive movement of the connecting element in a connecting element parallel to the coaxial axis 12 Connecting element for the drive perpendicular to the coaxial axis