Switching arrangement

Abstract

A switching arrangement has a first contact set and a second contact set which can be moved with respect to the first contact set, and an insulating nozzle arrangement. The insulating nozzle arrangement is supported on the first contact set which includes a first arcing contact piece. The first arcing contact piece can be moved with respect to the insulating nozzle arrangement.

Claims

1. A switching arrangement, comprising: a first contact set; a second contact set movably mounted relative to said first contact set; an insulating nozzle arrangement supported on said first contact set, said insulating nozzle arrangement having a main nozzle and an auxiliary nozzle commonly delimiting a nozzle channel, with said main nozzle and said auxiliary nozzle each delimiting a portion of said nozzle channel; and said first contact set having an arcing contact piece movably mounted relative to said insulating nozzle arrangement enabling a relative movement between said first arcing contact piece and said insulating nozzle arrangement.

2. The switching arrangement according to claim 1, wherein said insulating nozzle arrangement delimits a nozzle channel formed with a mouth opening arranged opposite a mouth opening of a channel of said arcing contact piece.

3. The switching device arrangement according to 2, wherein said nozzle channel serves to convey a fluid medium, and fluid medium exiting from said mouth opening of said nozzle channel flows into said channel.

4. The switching device arrangement according to 2, wherein said arcing contact piece has a contact socket and said channel is surrounded, at least in portions, by said contact socket of said arcing contact piece.

5. The switching device arrangement according to 1, wherein said first contact set has a first nominal current contact piece carrying said insulating nozzle arrangement at least in part.

6. The switching device arrangement according to 5, wherein said first arcing contact piece is surrounded at least in portions by said first nominal current contact piece.

7. The switching device arrangement according to 5, wherein said first arcing contact piece and said first nominal current contact piece are movably mounted relative to one another.

8. The switching device arrangement according to 5, wherein said second contact set has a second nominal current contact piece and a second arcing contact piece, and wherein each of said first and second arcing contact pieces are movable in relation to each of said first and second nominal current contact pieces in order to generate a relative movement therebetween.

9. The switching device arrangement according to 1, wherein: said first contact set has a first arcing piece and a first nominal current contact piece; said second contact set has a second arcing contact piece and a second nominal current contact piece; and each of said first and second arcing contact pieces and each of said first and second nominal current contact pieces perform switching movements driven by a common drive arrangement.

10. An actuation method for switching a switching arrangement having a first contact set with a first arcing contact piece, a second contact set that is movable relative to the first contact set, and an insulating nozzle arrangement supported on the first contact set, the method which comprises: on occasion of a switch-on procedure, moving the first contact set and the second contact set towards one another, and thereby reducing a spacing distance of the first arcing contact piece from the insulating nozzle arrangement by moving the first arcing contact piece relative to the insulating nozzle arrangement.

11. The actuation method according to 10, which comprises, for a switch-on procedure, following an initiation of a switching movement of the first contact set, moving the first arcing contact piece out from a field shadow of a first nominal current contact piece.

12. The actuation method according to 10, which comprises, for a switch-off procedure, enlarging a distance between the first arcing contact piece and the insulating nozzle arrangement before a switching arc is extinguished.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) An exemplary embodiment of the invention will be shown hereinafter schematically in a drawing and described in greater detail further below. In the drawing

(2) FIG. 1 shows an electrical switching arrangement in the switched-off state,

(3) FIG. 2 shows an electrical switching arrangement in the switched-on state,

(4) FIGS. 3 to 6 show a transition of the electrical switching arrangement from a switched-on state into a switched-off state,

(5) FIG. 7 shows a reduction gear for producing a relative movement between a first arcing contact piece and an insulating nozzle arrangement, and

(6) FIG. 8 shows an alternative reduction gear.

DESCRIPTION OF THE INVENTION

(7) FIG. 1 shows a switching arrangement in section. The switching arrangement has an encapsulating housing 1. The encapsulating housing 1 is substantially tubular and is oriented coaxially with a longitudinal axis 2. The encapsulating housing 1 is fabricated for example from electrically conductive material and surrounds an interrupter unit arranged in the interior. The encapsulating housing 1 preferably conveys ground potential. The interrupter unit has a first contact set 3 and a second contact set 4. The interrupter unit is supported relative to the encapsulating housing 1 by means of electrically insulating support insulators. A support insulator 5 is illustrated in FIG. 1 by way of example. The encapsulating housing 1 has, on its outer circumference, a plurality of flange pieces 6, 7. The flange pieces 6, 7 are used for insertion of phase conductors into the interior of the encapsulating housing 1 so as to electrically contact the interrupter unit located there and to incorporate said unit into a current path to be interrupted. The phase conductors penetrate the flange supports 6, 7, arranged on the outer circumferential side, in an electrically insulated and fluid-tight manner. Disk-shaped insulators, which close the flange pieces 6, 7 in a fluid-tight manner, are arranged around the phase conductors in order to close the encapsulating housing 1 in a fluid-tight manner. Furthermore, end openings of the encapsulating housing 1 are closed by appropriate flange covers. The interior of the encapsulating housing 1 is filled with an electrically insulating fluid, for example sulfur hexafluoride gas or another electrically insulating gas. The electrically insulating fluid flushes over and flushes through the interrupter unit of the switching arrangement arranged in the interior of the encapsulating housing 1. The interrupter unit is oriented with its longitudinal axis in line with the longitudinal axis 2 of the encapsulating housing.

(8) The interrupter unit has a first supporting body 8 and a second supporting body 9. The first supporting body 8 is used to position the first contact set 3. The second supporting body 9 is used to position the second contact set 4. The two supporting bodies 8, 9 are in the present case formed differently from one another. However, identical supporting bodies 8, 9 can also be used. The two supporting bodies 8, 9 are each formed as hollow bodies, which are substantially rotationally symmetrical, wherein the two supporting bodies 8, 9 comprise an electrically conductive material (for example a metal) and are electrically conductively contacted with the phase conductors guided through the flange pieces 6, 7 into the interior of the encapsulating housing 1. The supporting bodies 8, 9 thus form part of a current path which is to be interrupted by the switching arrangement. The two supporting bodies 8,9 are oriented with their axes of rotation coaxial with the longitudinal axis 2 and are arranged at a distance from one another, wherein end faces, facing toward one another, of the two supporting bodies 8, 9 are connected to one another at a fixed angle via an electrically insulating spacer 10. The spacer 10 is illustrated in FIG. 1 symbolically. The electrically insulating spacer 10 can surround the longitudinal axis 2 in closed form, for example in the manner of a pipe. However, the electrically insulating spacer 10 may also have a plurality of bars distributed over a circumference about the longitudinal axis 2, which bars connect the two supporting bodies 8, 9 to one another at a fixed angle in the manner of a cage.

(9) The switching chamber 11 of the switching arrangement is arranged in the region of the electrically insulating spacer 10. An insulating nozzle arrangement 12 protrudes into the switching chamber 11. In the present case the insulating nozzle arrangement 12 has a main nozzle 12a and also an auxiliary nozzle 12b. The main nozzle 12a and also the auxiliary nozzle 12b jointly delimit a nozzle channel, which is oriented coaxially with the longitudinal axis 2. The main nozzle and auxiliary nozzle 12a, 12b are each rotationally symmetrical, wherein the auxiliary nozzle 12b protrudes into the main nozzle 12a. An annular channel is formed between the main nozzle 12a and the auxiliary nozzle 12b, which channel leads into the nozzle channel from the radial direction. The annular channel connects the nozzle channel to a heating volume 13. The insulating nozzle arrangement 12 is connected via its main nozzle 12a and its auxiliary nozzle 12b at a fixed angle to an axially displaceable first nominal current contact piece 14, which is positioned in the first supporting body 8. An axial movement of the first nominal current contact piece 14 in the direction of the longitudinal axis 2 is transmitted to the insulating nozzle arrangement 12, such that this is moved similarly to the first nominal current contact piece 14. The first nominal current contact piece 14 is contacted electrically conductively with the first supporting body 8 by means of sliding contact. Furthermore, the first contact set 3 has a first arcing contact piece 15. The first arcing contact piece 15 is tubular and is oriented coaxially with the longitudinal axis 2. At its end facing toward the nozzle channel of the insulating nozzle arrangement 12, the first arcing contact piece 15 has a contact socket for forming a contact region of the first arcing contact piece 15. The contact socket surrounds a mouth opening of a channel formed on the inner circumferential side on the tubular first arcing contact piece 15. The first arcing contact piece 15 is electrically conductively connected to the first supporting body 8 via a sliding contact arrangement. The first arcing contact piece 15 and also the first nominal current contact piece 14 thus always have the electric potential of the first supporting body 8. A drive rod 16 is coupled to the end of the first arcing contact piece 15 facing away from the nozzle channel of the insulating nozzle arrangement 12. The drive rod 16 is equipped for this purpose with a transverse pin, which is guided in a slot of a drive element 25 of the first nominal current contact piece 14 or the insulating nozzle arrangement 12. The drive rod 16 penetrates a wall of the encapsulating housing 1 in a fluid-tight manner. It is thus possible to transmit a movement produced outside the encapsulating housing 1 to the first contact set 3.

(10) The mouth opening of the channel of the first arcing contact piece 15 is arranged at a distance from an end mouth opening of the nozzle channel of the insulating nozzle arrangement 12. The mouth opening of the nozzle channel lies in a recess of the insulating nozzle arrangement 12, into which the first arcing contact piece 15 protrudes. The first arcing contact piece 15 protrudes into the recess of the insulating nozzle arrangement irrespectively of the switching position of the switching device. A movement of the first nominal current contact piece 14 is also coupled in at the first arcing contact piece 14 via a reduction gear 17 (see FIG. 7). For this purpose the reduction gear 17 has a lever arrangement, which in the event of a switch-on procedure moves the first nominal current contact piece 14/the insulating nozzle arrangement 12 and moves the first arcing contact piece 15 at an increased speed. In the event of a switch-off procedure a movement of the first nominal current contact piece 14/the insulating nozzle arrangement 12 is performed as well as a movement of the first arcing contact piece 15 at an increased speed.

(11) A movement of the first nominal current contact piece 14 is also transmitted to the insulating nozzle arrangement 12 on account of the coupling of the insulating nozzle arrangement 12 to the first nominal current contact piece 14 at a fixed angle. Here, the insulating nozzle arrangement 12 is contacted in the inner circumferential side against the first nominal current contact piece 14 and surrounds at least the contact region with the contact socket of the first arcing contact piece 15 on the outer circumferential side. Furthermore, a gap of variable dimension located between the mouth openings of the nozzle channel and of the channel of the first arcing contact piece 15 is surrounded by the insulating nozzle arrangement 12.

(12) A connecting rod 18 of a slider crank gearing is struck in the region of the end mouth opening of the nozzle channel of the insulating nozzle arrangement 12, which faces away from the first arcing contact piece 15. The connecting rod 18 ends at a crank arm 20 mounted in a stationary manner on the second supporting body 9. The crank arm 20 is a pivoted lever and converts an axial movement of the insulating nozzle arrangement 12 into a rotary movement. A slotted guide path 21 is arranged in the crank arm 20, in which path a sweeping element is guided, which is connected to a linearly displaceable second nominal current contact piece 22. The second nominal current contact piece 22 is mounted axially displaceably on the second supporting body 9 and is electrically conductively connected to the second supporting body 9. The second nominal current contact piece 22 is formed as a hollow cylinder, wherein, coaxially with the second nominal current contact piece 22, a second arcing contact piece 23 is surrounded by the second nominal current contact piece 22. The second arcing contact piece 23 is mounted displaceably on the second nominal current contact piece 22. A supplemental movement can be coupled in at the second arcing contact piece 23 via a further gearing 24 during the course of a movement of the second nominal current contact piece 23, such that the movement profile of the moving second nominal current contact piece 22 forms the basis for a movement of the second arcing contact piece 23, wherein the movement profiles of the first nominal current contact piece 22 and of the second arcing contact piece 23 supplement one another, such that the second arcing contact piece 23 can be moved with respect to the second supporting body 9 at a greater speed than the second nominal current contact piece 22.

(13) A relative movement of the first arcing contact piece 15 relative to the insulating nozzle arrangement 12 is ensured independently of the embodiment of the second contact set 4. By way of example, merely a drive of the first nominal current contact piece 14 and of the first arcing contact piece 15 may also be provided in order to generate a relative movement between the first and the second arcing contact piece 15, 23 and also between the first and the second nominal current contact piece 14, 22, wherein the second nominal current contact piece 22 and the second arcing contact piece 23 by way of example remain unchanged with respect to the second supporting body 9.

(14) FIGS. 2, 3, 4, 5 and 6 illustrate a switching process for reaching the switched-off position proceeding from the switched-on position of the switching arrangement illustrated in FIG. 2, passing via FIGS. 3, 4 and 5. In particular it can be seen that in the switched-on state (FIG. 2) the distance of the mouth opening of the channel of the first arcing contact piece 15 from the end mouth opening of the nozzle channel of the insulating nozzle arrangement 12, which faces toward the first arcing contact piece 15, has the smallest value. At the start of a switch-off movement (FIG. 3), the first nominal current contact piece 14 and the first arcing contact piece 15 are first moved. The second nominal current contact piece 23 still remains unchanged, since the slotted guide path 21 of the crank arm 20 does not couple in any movement at the first nominal current contact piece 14 on account of the course of said path lying concentrically with the pivot point in this region. As a result, the second arcing contact piece 23, which is supported on the second nominal current contact piece 23, also remains unchanged. Following a separation of the first nominal current contact piece 14 from the second nominal current contact piece 23 (FIG. 4), a movement in the opposite direction is then transmitted to the second arcing contact piece 23. Subsequently (FIG. 5), both the first nominal current contact piece 14 and the second nominal current contact piece 22 and also the first arcing contact piece 15 and also the second arcing contact piece 23 are distanced from one another. Here, the first arcing contact piece 15 is removed from the region of the switching chamber 11 more quickly than the first nominal current contact piece 14 is removed from the switching chamber 11. The first arcing contact piece 15 is moved into the shield region of the first nominal current contact piece 14, whereby a distance of the first arcing contact piece 15 from the mouth opening of the nozzle channel of the insulating nozzle arrangement 12 facing toward the first arcing contact piece 15 is increased. A switch-off arc ignited following the contact separation of the two arcing contact pieces 15, 23 (change from FIG. 4 to FIG. 5) burns between the two arcing contact pieces 15, 23 and is guided within the nozzle channel of the insulating nozzle arrangement 12. The switching arc expands what is known as switching gas within the nozzle channel, said gas being able to escape via the end mouth opening of the nozzle channel, which opening faces toward the first arcing contact piece 15. The switching gas escaping from the nozzle channel of the insulating nozzle arrangement 12 enters the mouth opening of the channel of the first arcing contact piece 15. The first arcing contact piece 15 discharges the switching gas from the switching chamber. In addition, the radial annular channel formed between the main nozzle 12a and the auxiliary nozzle 12b is used to discharge switching gas from the region of the burning switching arc from the nozzle channel of the insulating nozzle arrangement 12. This switching gas is introduced into the hating volume 13. The expanded switching gas is compressed within the heating volume 13 on account of the thermal energy input. Said gas is thus prevented from escaping on account of the burning arc and the nozzle channel of the insulating nozzle arrangement 12 plugged by the second arcing contact piece 23.

(15) Only following a pressure reduction (switching arc extinguishing) in the nozzle channel can the compressed switching gas flow back from the heating volume 13 and escape via the end mouth openings of the nozzle channel of the insulating nozzle arrangement 12. Here, the clearance between open contacts is flushed and dielectrically reinforced.

(16) The reduction gear 17 is illustrated in detail in FIG. 7. The drive rod 16 is connected via a transverse pin to a drive element 25 of the first nominal current contact piece 14 or the insulating nozzle arrangement 12. For this purpose, the transverse pin engages with a slot in the drive element 25. It is thus possible, in the event of a linear movement of the drive rod 16, to couple in this linear movement directly at the first nominal current contact piece 14 or the insulating nozzle arrangement 12 via the flanks of the slot. The reduction gear 17 is also provided with a single-arm lever 26. The single-arm lever 26 is attached in a stationary manner to the first supporting body 8. The single-arm lever 26 is connected at the free end thereof to the transverse pin in the slot of the drive element 25. A coupling is thus provided via the single-arm lever 26 to the drive rod 16, which is linearly displaceable in order to transmit a movement. The single-arm lever 26 is pivoted in the event of a movement of the drive rod 16. In order to compensate for an overstroke of the single-arm lever 26, this slides through the slot of the drive element 25. Here, the resiliently deflectable drive rod 16 is moved out from its coaxial position in relation to the longitudinal axis 2 via the transverse pin in order to compensate for an overstroke of the single-arm lever 26. The single-arm lever 26 is also provided with a drive pin 27, wherein the distance of the drive pin 27 from the pivot point of the single-arm lever 26 is greater than the distance of the transverse pin from the pivot point of the single-arm lever 26. Accordingly, in the event of a pivoting of the single-arm lever 26, the drive pin 27 covers a greater path than the transverse pin, such that a movement at the drive pin 27 deviating from the movement of the transverse pin can be determined. A tab 28 strikes against the drive pin 27 and is connected to the linearly displaceable first arcing contact piece 15. In the present case the tab 28 is connected via a linearly displaceable thrust element, which is guided in the interior of the tubular drive element 25. The tab 28 is diverted in an elbowed manner through an opening in the outer circumferential side of the drive element 25 and is coupled to a slot on the drive pin 27. Here, the slot is directed in such a way that it is possible to compensate for an overstroke of the drive pin 27 located on the single-arm lever 26. Proceeding from the drive rod 16, a movement is thus transmitted onto the first nominal current contact piece 14 by the reduction gear 17, wherein a movement of increased speed is coupled in at the first arcing contact piece 15 with use of the single-arm lever 26 positioned in a stationary manner.

(17) FIG. 8 shows an alternative reduction gear. A double-arm lever 29 is mounted rotatably on the drive element 25 there. The drive rod 16 is connected to the drive element 25, such that movements of the drive rod 16 are transmitted directly onto the drive element 25 and consequently also onto the first nominal current contact piece 14 and also the insulating nozzle arrangement 12.

(18) The double-arm lever 29 is connected via one of its lever arms to a tab 28, which is guided in a linearly displaceable manner in the drive element 25 and transmits a movement onto the first arcing contact piece 15. In order to generate a movement of the first arcing contact piece 15 relative to the first nominal current contact piece 14, a slotted guide path 30 is positioned on the first supporting body 8. The other lever arm of the double-arm lever 29 sweeps through the slotted guide path 30, whilst the pivot point of the double-arm lever 29 is moved jointly with the drive element 25. On account of the shaping of the slotted guide path 30, an initiation or interruption of a transmission of a movement of the tab 28/of the first arcing contact piece 15 can be easily set. In the present case the end regions of the slotted guide path 30 are arranged parallel to the movement axis of the drive element 25. Thus, when passing the end regions, no additional movement is coupled in at the first arcing contact piece 15. The arcing contact piece 15 is moved jointly with the first nominal current contact piece 14 and the insulating nozzle arrangement 12 during the sweeping of the end regions. A central portion located between the end regions of the slotted guide path 30 has a gradient, such that an additional movement is coupled in here at the first arcing contact piece 15. Consequently, the distance of the mouth opening of the channel of the first arcing contact piece 15 from the facing mouth opening of the nozzle channel is reduced. The first arcing contact piece 15 also moves from the field shadow of the first nominal current contact piece 14. By varying the shaping of the slotted guide path 30, the movement profile of the first arcing contact piece 15 can be changed.