EP2126947A2

EP2126947A2 - Compressed-gas cutout having a radial flow opening

Info

Publication number: EP2126947A2
Application number: EP07857869A
Authority: EP
Inventors: Jürg Nufer; Martin Kriegel; Olaf Hunger; Marialuisa Perela
Original assignee: ABB Technology AG
Current assignee: ABB Schweiz AG
Priority date: 2006-12-27
Filing date: 2007-12-19
Publication date: 2009-12-02
Anticipated expiration: 2027-12-19
Also published as: US8546716B2; WO2008080858A3; WO2008080858A2; EP2126947B1; CN101573774A; US20090261071A1; EP1939910A1; CN101573774B

Abstract

The compressed-gas cutout (10) according to the invention comprises a first contact (14) and a second contact (18), which are displaceable relative to each other along a longitudinal axis (A). A blow volume (54, 52, 68) is provided around the first contact (14). Said blow volume (54, 52, 68) is connected via a gas channel (44) to an electric arc zone (40) in order to blow at an electric arc produced when disconnecting the first contact (14) from the second contact (18). The blow volume (54, 52, 68) is delimited radially on the outside by a disconnecting element (30), which disconnects the blow volume (54, 52, 68) from a low-pressure chamber (72). In the radial direction, a flow opening (64, 66, 68) enabling gas exchange leads from the low-pressure chamber (72) into the blow volume (54, 52, 68).

Description

PRESSURE CONTROL SWITCH WITH A RADIAL THROUGH OPENING UNC

DESCRIPTION

Technical area

The invention relates to the field of medium-voltage switch technology and high-voltage switch technology, in particular the power switch in power distribution networks. It relates in particular to a compressed gas switch according to the preamble of claim 1 or of claim 5.

State of the art

Such gas blast switches are well known in particular in high voltage engineering.

For example, WO 98/43265 discloses such a compressed gas switch. This has a first, drivable arcing contact, a second, fixed arcing contact, a rated current path running concentrically therewith and a compression device in order to compress quenching gas in a blowing volume. The compressed quenching gas is used to extinguish an arc resulting from the separation of the first arcing contact from the second arcing contact by blowing it with quenching gas.

The first, drivable arcing contact is carried by a switching tube. At an exit of this switching tube an exhaust volume is provided, in which the quenching gas is passed after the blowing of the arc. The arranged within the nominal flow path exhaust volume communicates with a low pressure space outside the nominal flow path via exhaust ports in combination. Next, the exhaust volume is separated by a partition wall of a suction, which is also arranged between blowing volume and exhaust volume within the nominal flow path. This intake area is connected to the blowing volume via a scavenging valve as well as via a pressure relief valve. Through the partition, the movable switching tube is passed tightly.

This known gas pressure switch solves the problem that in the intake should prevail at least a nearly constant gas pressure, so that the gas pressure in the exhaust volume has no effect on the function of the purge valve as well as on the function of the pressure relief valve. However, it proves to be disadvantageous that the dividing wall is arranged within the tube-shaped nominal flow path. Since the partition wall is exposed to a high pressure difference between the intake area and the exhaust volume during the separation of the first arcing contact from the second arcing contact, this requires a stable attachment of the partition wall to an inner wall of the rated flow path and a sealed passage of the switching tube through this partition wall.

Next is also known from US 2003/01 73335 Al and corresponding to this document DE 603 05 522 T2, a high-voltage circuit breaker known. This known power switch has between a thermal chamber and an expansion space to an evacuation line, which is arranged axially symmetrical to the axis of movement of the movable contacts. The evacuation line extending in the axial direction is closed by means of a valve which opens at high overpressure in the thermal arc quenching chamber. From EP O 1 46 671 Al a further compressed gas switch is known. In order not to increase a pressure in a piston volume above a predetermined value when opening the gas pressure switch, this gas pressure switch has a radially arranged pressure relief valve. This ensures that, in the event of excessive overpressure in the piston volume, gas can escape through this pressure relief valve.

From EP 0 296 363 A2 a further compressed gas switch with self-generated extinguishing gas flow is known. This compressed gas switch has a compression space. In order to prevent an excessive pressure in the compression space, this gas pressure switch has a valve, through which gas can flow out of the compression space radially.

Presentation of the invention

Object of the present invention is to propose a compressed gas switch with a simplified design, which thereby also allows a more compact design. Next, the inventive gas pressure switch should have a high reliability.

The above object is achieved according to the invention by a compressed gas switch with the features of claim 1. Likewise, this object is achieved by a gas pressure switch with the features of claim 5.

The inventive gas pressure switch according to claim 1 according to the invention a gas exchange between the low-pressure chamber and the blowing volume enabling, non-closable flow-through. The non-closable flow-through opening extends through an area the separating element, which separates the blowing volume in the radial direction with respect to the longitudinal axis of the low pressure space. Consequently, extinguishing gas can flow out of the blowing volume into the low-pressure space, in particular in the event of excessive overpressure in the blowing volume. Consequently, the gas pressure in the blowing volume can not rise arbitrarily. Next, a particularly simple construction of the gas pressure switch can be realized.

According to a preferred embodiment according to claim 3, the blowing volume is subdivided into a compression space and into a heating space, wherein the non-closable flow opening opens into the compression space. It can thereby be achieved that the pressure in the compression space can not rise arbitrarily and unused extinguishing gas can flow away from the compression space into the low-pressure space. Also, quenching gas can flow from the low pressure space into the compression space.

According to a preferred embodiment according to claim 4, the gas pressure switch on a further, closable flow opening, which can be closed by means of a spool valve designed as a check valve.

The inventive gas pressure switch according to claim 5 has a gas exchange permitting flow opening between the low pressure space and a blowing volume through a region of a partition member through which separates the blowing volume from the low pressure chamber in the radial direction with respect to the longitudinal axis of the gas pressure switch. According to the invention, a flush valve is arranged in or at the flow-through opening. It can thereby be achieved that for filling the blowing volume with extinguishing gas, this extinguishing gas can flow from the low-pressure space into the blowing volume or into the compression space, but not in the opposite direction Direction. Further, since the gas pressure is at least approximately constant on the side of the low pressure space, the purge valve opens at a predetermined pressure regardless of the pressure history during the shift operation.

The blowing volume of the gas pressure switch is connected, for example via a channel with an arc zone of the gas pressure switch through which during a first phase of a shutdown heated quenching gas, such as SFε, (sulfur hexafluoride) passes from the arc zone in the blowing volume. At a subsequent, further phase extinguishing gas flows from the blowing volume through the channel to the arc zone to blow a burning there arc. The quenching gas then flows further into an exhaust volume.

By means of the flow-through opening and the scavenging valve it can be achieved that quenching gas can flow from the low-pressure chamber into the blowing volume. By the inventive leadership of the flow opening in the radial direction of the gas pressure switch can be made compact in the longitudinal direction. Furthermore, this connection of the low-pressure chamber with the blowing volume proves to be advantageous, since at least approximately a constant pressure prevails in the low-pressure space at any point in the switching process and the extinguishing gas is not ionized and cool in the low-pressure space.

According to a preferred embodiment according to claim 7, the Spϋlungsventil and a pressure relief valve in the same or at the same flow opening are arranged. This allows a particularly compact design of the gas pressure switch as well as a simple final assembly of the gas blast switch. In particular, the Spϋlungsventil and the pressure relief valve can be pre-assembled as a unit. According to a preferred embodiment according to claim 8, the compressed gas switch on a further flow opening, which can be closed by means of a pressure relief valve. It can thereby be achieved that at a predetermined overpressure in the compression chamber or in the blowing volume, quenching gas can flow out into the low-pressure space. Since there is at least approximately a constant gas pressure in the low pressure space, the pressure relief valve opens at a predetermined response pressure. It can thereby be achieved that no unauthorized high pressure is built up in the compression space or in the blowing volume. This can prevent that the operation of the gas pressure switch is impaired due to an excessive gas pressure in the compression chamber or blowing volume.

According to a preferred embodiment according to claim 10, the blowing volume is subdivided into a compression space and into a heating space, the flow opening opening into the compression space. As a result, it can be achieved that unused extinguishing gas can flow through the scavenging valve from the low-pressure space into the compression space and through the overpressure valve from the compression space into the low-pressure space.

According to a preferred embodiment according to claim 1 8, the compressed gas switch on a closable by a check valve Spulskanal between the compression chamber and the exhaust volume. Next, the gas pressure switch on the flow-through, in particular the non-closable flow-through, between the low-pressure chamber and the blowing volume or the compression chamber. Through the flow-through a type of pressure relief valve can be realized in the simplest way, wherein the flow-through, if no valve this closes, always open. By choosing the geometry of the flow opening, a gas flow can be controlled by them.

Further preferred embodiments and advantages will be apparent from the further dependent claims and the figures.

Brief description of the drawings

In the following, the subject invention will be explained in more detail with reference to preferred Ausfϋhrungsbeispielen, which are illustrated in the accompanying drawings. It shows purely schematically:

1 shows an inventive gas pressure switch, in particular a circuit breaker, which has two flow openings between a low-pressure chamber and a compression chamber, wherein the one flow-through through a Spϋlungsventil and the other flow-through is closed by a pressure relief valve;

Fig. 2 is a partial view of a gas pressure switch, which for

Closing a formed between the low-pressure chamber and the compression space flow opening has a pressure relief valve, which in an assembly with an intermediate valve designed as a check valve between the

Boiler room and the compression space is formed;

3 shows a partial view of the compressed gas switch according to the invention in accordance with a third exemplary embodiment in which the flow-through opening shown in FIG. 2 is closed between the compression chamber and the low-pressure chamber, the pressure relief valve is combined with a flushing valve according to the invention in a two-way valve;

4 is a partial view of the inventive gas pressure switch according to a fourth Ausfϋhrungsbeispiel.

5 is a partial view of the inventive gas pressure switch according to a fifth Ausfϋhrungsbeispiel.

6 shows an inventive gas pressure switch, in particular a circuit breaker, which has two flow-through openings between a low-pressure chamber and a compression chamber, wherein the one flow-through is closed by a Spϋlungsventil and the other

Flow-through can not be closed; and

7 shows a compressed gas switch according to the invention, which has a radially arranged, non-closable flow-through opening and an axially arranged scavenging valve.

The reference numerals used in the figures and their meaning are listed in the list of reference numerals. Basically, the same or equivalent parts are provided with the same or similar reference numerals in the figures. For the understanding of the invention non-essential parts are not shown in part. The embodiments described are exemplary of the subject invention and have no limiting effect. Ways to carry out the invention

Fig. 1 shows a compressed gas switch, in particular a circuit breaker, according to a first Ausfϋhrungsbeispiel of the invention. Such gas blast switches are used in particular in high-voltage switchgear.

The gas blast switch 10 has a tube 1 2 formed as a first contact 1 4, which is intended to act together with a designed as a pin 1 6 second contact 1 8. Preferably, the first contact 14 as well as the second contact 1 8 at least at their free end portions of a burn-resistant material, in particular made of tungsten and copper. The tube 1 2 and the pin 1 6 are arranged on a common longitudinal axis A and movable relative to each other. In the exemplary embodiment shown in FIG. 1, the first contact 1 4 is designed to be movable. The associated drive assembly is not shown.

The free end portion 20 of the first contact 1 4 is formed as a contact tulip with a plurality of contact fingers in a known manner. The free end portions of the contact fingers are preferably made of the erosion resistant material.

Around the first contact 14 around a hollow cylindrical shape having a separating element 30 is arranged, wherein the one end portion 32 of the partition member 30 tapers. The free end of the tapered end portion 32 is aligned in the direction of the longitudinal axis A substantially with the free end of the first contact 14. In the circumferential direction, a stationary conductor element 33 engages around the other end region of the separating element 30, which lies opposite the tapering end region 32 in the direction of the longitudinal axis A. A conductive connection between the conductor element 33 and the movable relative to the conductor element 33 separating element 30 is made by a contact spring 35. The contact can be made instead of a contact spring, for example, via a sliding contact, a spiral contact, a sliding tulip or a roller contact. This is inserted in a circumferential groove, which is formed radially inwardly in the free end region of the conductor element 33.

The separator 30 is part of a well-known nominal current contact arrangement not shown in the figures. The separator 30 forms a first rated current contact and is electrically connected to the first contact 1 4. The second contact 1 8 is electrically connected to a second rated current contact, not shown, and is intended to cooperate with the first rated current contact, the separating element 30, when the compressed gas switch is closed.

In the tapered end portion 32 of the partition member 30, a Dϋsenkörper 34 is arranged, wherein the Dϋsenkörper 34 protrudes from the separating element 30 in the direction of the longitudinal axis A. The nozzle body 34 is preferably made of an insulating material, such as polytetrafluoroethylene. The nozzle body 34 initially has a nozzle opening 36 from the end protruding from the separating element 30, which tapers in the direction of the longitudinal axis A toward the first contact 14 and merges into a nozzle channel 38. The nozzle channel 38 expands on the opposite side of the nozzle opening 36 to an inner diameter which is greater than an outer diameter of the contact tulip of the first contact 1 4, wherein the inner diameter is selected such that the contact fingers of the contact tulip have a sufficiently large game. The area within the nozzle body 34, which lies between the contact tulip and the free end, forms an arc zone 40. In the Dϋsenkanal 38 opens a gas channel 44 which connects the arc zone 40 with a heating chamber 46 in the interior of the separating element 30. This gas channel 44 is intended, on the one hand, to lead extinguishing gas, which is heated by an arc, from the arc zone 40 into the heating chamber 46. On the other hand, the gas channel 44 is intended to lead quenching gas from the heating chamber 46 for blowing the arc burning in the arc zone 40 into the arc zone 40. Typically, the heating chamber 46 has a constant volume.

The heating chamber 46 is limited in the radial direction by the separating element 30. In the direction of the nozzle opening 36, the heating chamber is also delimited by the separating element 30 as well as by the nozzle body 34. In the opposite direction to the nozzle opening 36 of the heating chamber 46 is bounded by an intermediate wall-like intermediate member 48. The first contact element 14 is guided tightly through the intermediate element 48. The intermediate element 48 is preferably held on the separating element 30 in a form-fitting manner. It may also be positively secured to the first contact 1 4.

By means of the intermediate element 48, an interior of the separating element 30 is subdivided into the heating space 46 and into a compression space 52. The interior of the separating element 30 - the heating chamber 46 and the compression space 52 - together form a blowing volume 54. The compression space 52 is bounded on the side opposite the intermediate element 48 by a piston 56, which is arranged stationary in the present case. The piston 56 is part of a cylinder-piston arrangement, wherein the cavity of this cylinder-piston assembly is formed by the compression space 52.

The piston 56 has a passage opening for the first contact 14. Between the piston 56 and the first contact 1 4 is a seal 80 in a recessed groove in the piston inserted to seal a gap between the first contact 14 and the piston 56. Furthermore, the seal 80 also forms a guide for the first contact 1 4. The piston 56 is sealed against the separating element 30 by means of a further seal 82, which is inserted into a further circumferential groove in the piston 56.

On the opposite side of the compression chamber 52 of the piston 56 is located within the conductor element 33, an exhaust volume 58. This is connected by a formed in the pipe 1 2 flow channel 59 with the arc zone 40 so that quenching gas, which from the heating chamber 46 through the gas passage 44 in the arc zone 40 flows, can flow through the flow channel 59 into the exhaust volume 58. During a high-current phase, quenching gas can also flow directly from the arc zone 40 into the exhaust volume 58.

Through the intermediate element 48 leads from the compression chamber 52 into the heating chamber 46, a channel 60 which is closable by a designed as a check valve intermediate valve 62 that at an overpressure in the compression chamber 52 relative to the heating chamber 46 quenching gas from the compression chamber 52 flows into the heating chamber 46. At an overpressure in the heating chamber 46 relative to the compression space 52, the intermediate valve 62 closes.

In the radial direction, a flushing passage 66 forming a flow-through opening 64 and an overpressure passage 68 likewise forming a flow-through opening 64 from the compression space 52 into a low-pressure space 72 radially adjoining the separating element 30. The low-pressure space 72 surrounds the rated-current contact arrangement. In the low-pressure space 72 prevails at least approximately during one Switching operation of the gas pressure switch 1 0 a constant gas pressure, which is preferably in the range of 3-7 bar.

The low-pressure space 72 is bounded by an envelope, not shown, of the gas pressure switch and connected to the exhaust volume 58 via a gas return duct.

According to the invention, the scavenging passage 66 can be closed by means of a scavenging valve 74 designed as a check valve in such a way that the purge valve 74 opens at a negative pressure in the compression space 52 relative to the low-pressure space 72 and otherwise closes.

The overpressure passage 68 can be closed by means of a pressure relief valve 76, which opens at a defined overpressure in the compression chamber 52 relative to the low pressure chamber 72 in order to build off any overpressure in the compression chamber 52.

Of course, a plurality of flushing passages 66 can also be provided which can each be closed by means of a flushing valve 74. Likewise, a plurality of overpressure passages 68 may be provided, each of which can be closed by means of a pressure relief valve 76.

The gas-blast switch shown in Fig. 1 operates as follows. First, the rated current contact arrangement is opened. Subsequently, the contact arrangement formed by the first Kantakt 14 and the second contact 1 8 is separated, whereby an arc ignites in the arc zone 40 because of the current flow through the contact arrangement. As a result, quenching gas is heated. This flows initially through the gas channel 44 in the heating chamber 46. When opening the contact arrangement is also by the movement of the separating element 30 together with the first contact 1 4 in Direction of the longitudinal axis A away from the second contact 1 8 of the compression space 52 reduced, whereby the gas pressure in this increases. If the gas pressure in the compression chamber 52 is greater than in the heating chamber 46, opens the intermediate valve 62, whereby quenching gas flows through the channel 60 from the compression chamber 52 into the heating chamber 46 and further increases the gas pressure in this. As soon as the gas pressure in the arc zone 40 decreases, quenching gas flows from the heating chamber 46 through the gas channel 44 into the arc zone 40 and inflates the arc, which is thereby extinguished.

However, if due to a strong current flow, for example triggered by an earth fault, the gas pressure in the heating chamber 46 rapidly increases to a high value, the situation may arise that the intermediate valve 62 remains closed in the heating chamber 46 during the separation process of the contact arrangement, or at least over a longer Period of time during the separation process is closed. As a result, the extinguishing gas from the compression chamber 52 does not flow into the heating chamber 46. Upon reaching a predetermined gas pressure in the compression volume 52 now opens the pressure relief valve 76, which quenching gas can flow through the pressure passage 68 into the low-pressure chamber 72. Since an at least almost constant gas pressure prevails in the low-pressure space 72, in particular during the separation process, the maximum pressure in the compression space 52 is defined by the response pressure of the pressure relief valve 76. It can thereby be achieved that a force necessary for opening the contact arrangement, in particular for retracting the separating element 30 together with the first contact 1 4 into the conductor element 33, does not exceed a maximum force. Thereby, the drive arrangement can be designed such that the contact arrangement can be reliably separated even at high current flow. The extinguishing gas used for blowing the arc in the arc zone 40 flows on the one hand through the flow channel 59 into the exhaust volume 58 and on the other hand through the nozzle opening 36. In the exhaust volume 58, the hot quenching gas is cooled. A gas exchange between exhaust volume 58 and low-pressure space 72 can take place via a gas return, not shown.

When closing the contact arrangement, the volume of the compression chamber 52 increases, whereby in this compared to the low-pressure chamber 72 as well as the heating chamber 46, a negative pressure is created. As a result, the scavenging valve 74 according to the invention opens, which releases the scavenging passage 66 for the flow of quenching gas from the low-pressure space 72 into the compression space 52. As soon as the gas pressure in the compression volume 52 rises above the gas pressure in the low-pressure space 72, the purge valve 74 closes. The inflow of the quenching gas from the low-pressure chamber 72 into the blowing volume 54, in particular into the compression space 52, ensures that even shortly after opening the gas-blast switch cold extinguishing gas flows into the blowing volume 54 or in the compression space 52. As a result, it can be ensured that this works reliably in the case of briefly successive separation processes of the gas blast switch.

In an exemplary embodiment according to the invention shown in FIG. 6 and described in detail in connection with FIG. 6, reference is made to FIG

Relief valve 76 is omitted at the overpressure passage 68. By the light

Diameter of the pressure passage 68 can still the quenching gas flow through the pressure relief passage 68, in particular at an overpressure in

Compression space 52 relative to the low pressure chamber 72, are controlled. Consequently, when separating the first contact 1 4 from the second contact 1 8, at the same time the volume of the compression chamber 52 is reduced, quenching gas from the compression chamber 52 into the low-pressure space 72 to flow. Consequently, the gas pressure in the compression space 52 can not increase arbitrarily.

2, another example of a gas blast switch is shown. In essence, this Ausfϋhrungsbeispiel corresponds to the gas pressure switch 10 shown in Fig. 1. It will be discussed here only on the differences.

In this embodiment, the separating element 30 has only the throughflow opening 64, which forms the overpressure passage 68 and can be closed by means of the overpressure valve 76. The separating element 30 preferably has a plurality of overpressure passages 68 closable by means of one or more pressure relief valves 76. Preferably, 4-8 overpressure passages 68 are formed on the partition member 30. The overpressure passages 68 may also be formed as slots.

The intermediate element 48 shown in FIG. 2 is integrally formed with the tube 1 2 of the first contact 14. Of course, the intermediate piece and the tube 1 2 may be formed consisting of several individual elements.

In order to form the pressure relief valve 76, the intermediate element 48 has an open in the direction of the piston 56 annular channel 86, in which the

Overpressure passage 68 opens in the radial direction. The annular channel forms, together with the overpressure passage 68, a connecting channel 87

Ring channel 86 is in the radial direction on the one hand by an am

Intermediate member 48 formed wall 88 and on the other hand limited by the separating element 30. In the annular channel 86 is one in the direction of the longitudinal axis A slidably mounted annular disc 90 arranged as a valve disc. This is pressed by springs 92 in the direction of the opening of the annular channel 86, wherein a stop restricts the freedom of movement of the annular disc in the direction of the opening.

The pressure relief valve 76 operates as follows. In the event of an overpressure in the compression space 52, the connection channel 87 adjoining the overpressure passage 68 is closed by the annular disk 90 located between the separating element 30 and the wall 88. As soon as the gas pressure in the compression chamber 52 rises above the response pressure of the pressure relief valve 76 defined by the springs 92, the annular disk 90 moves in the axial direction A into the annular channel, into the position indicated by broken lines in FIG. In this position, the annular disk 90, the pressure relief valve 76 is opened and quenching gas can flow freely through the connecting channel 87 and the pressure relief passage 68 adjacent thereto.

The piston 56 has a scavenging passage 66 'which, according to the scavenging passage 66 described in connection with FIG. 1, can be closed by means of a scavenging valve 74' designed as a check valve. The purge passage 66 leads from the exhaust volume 58 into the compression space 52.

By arranged on the first contact 1 4 intermediate element 48 of the channel 60 is performed in the direction of the longitudinal axis A. Preferably, the intermediate element 48 has a plurality of circumferentially regularly arranged channels 60. The channel 60 or the channels 60 is / are closable by means of a valve plate of the intermediate valve 62. The valve plate is preferably in turn formed as a circular ring disk. The conductor element 33 is designed to be elongated in the direction of the longitudinal axis A in comparison with the exemplary embodiment shown in FIG. Between the partition member 30 and the extended portion of the partition member 30, a gap 94 is formed. The overpressure passage 68 opens into this intermediate space 94. From the intermediate space 94, a channel 96 leads into the low-pressure space 72.

A third exemplary embodiment according to the invention is shown in FIG. For the elements shown in Fig. 3, which have already been described in connection with Fig. 2, reference is made to the description of Fig. 2. Identical or equivalent parts are provided with the same reference numerals.

The overpressure passage 68 also forms the purge passage 66 in this embodiment, that is, the purge passage 66 and the overpressure passage 68 are formed as a common flow passage 64. On the described in connection with FIG. 2 Spülungsdurchlass through the piston 56 is omitted in this embodiment.

The flow-through opening 64 can be closed by a two-way valve 98. This two-way valve 98 opens at a negative pressure in the compression chamber 52 relative to the low-pressure chamber 72 and thus acts as a purge valve. At overpressure in the compression chamber 52 relative to the low pressure chamber 72, the two-way valve 98 acts as a pressure relief valve, the two-way valve 98 opens only at a defined set pressure. As a result, a gas flow from the compression chamber 52 into the low-pressure space 72 is made possible. The two-way valve 98 may be formed as follows. The intermediate element 48 is the same as that described in connection with FIG. 2 intermediate element with the open annular channel 86 is formed. In these opens the flow opening 64, which together with the annular channel 86 form the connecting channel 87. Of course, several flow openings can open into the annular channel 86. In the annular channel 86 in the direction of the longitudinal axis A slidably mounted annular disc 90 is arranged. This is pressed by springs in the direction of the opening of the annular channel 86, wherein a stop restricts the freedom of movement of the annular disc 90 in the direction of the opening of the annular channel 86. The annular disc 90 forms together with the spring and the stop for the annular disc 90, the pressure relief valve of the two-way valve 98. The annular disc 90 has a plurality of spaced from the edge of the annular disc 90 holes 100, through which each one in the direction of the longitudinal axis A. extending guide element 102 is guided. The guide element 1 02 is fixedly connected to the intermediate element 48. At the free end of the guide member 102, a stop for a valve plate 1 04 is formed. This valve plate 1 04 is freely movable on the guide element 1 02 between the stop and the annular disc 90 and forms the flush valve of the two-way valve 98th

The two-way valve 98 operates as follows. In the case of an overpressure in the compression space 52, the connecting channel 87 is closed by the annular disk 90 located between the separating element 30 and the wall 88. The holes 1 00 of the annular disc are closed by the valve plate 1 04. As soon as the gas pressure in the compression chamber 52 rises above the setpoint pressure of the two-way valve 98 acting as a pressure relief valve 98, the annular disk 90 moves together with the valve disks 104 in the axial direction A into the annular channel into that shown in FIG broken lines indicated position. In this position the Ring disk 90 and the valve disks 104 can discharge extinguishing gas from the compression chamber 52 through the connecting channel 87 into the low-pressure chamber 72.

If a negative pressure prevails in the compression space 52 compared to the low-pressure space 72 (this case is shown in FIG. 3), the two-way valve 98 opens by the valve disks 1 04 moving away from the annular disk due to the pressure difference. As a result, the holes 100 of the annular disc are released, whereby quenching gas from the low-pressure chamber 72 can flow into the compression chamber 52.

As shown in Fig. 4, the intermediate member 48 is particularly preferably formed as a prefabricated assembly which is inserted into the partition member 30 and the first contact 14 engages. On the intermediate element 48, the scavenging valve 74 shown in FIG. 1, the overpressure valve 68 formed as a check valve and the intermediate valve 62 are preferably formed. This allows a particularly compact design of the gas blast switch can be achieved. Next, the assembly of the gas pressure switch is significantly simplified thanks to the intermediate element 48. In Fig. 4, the Spϋlungsventil and the pressure relief valve as described in connection with FIG. 3 as a two-way valve 98 are formed.

5, the axially displaceable annular disk of the intermediate valve 62 and the likewise axially displaceable valve disk 104 of the part of the two-way valve forming the scavenging valve 74 are shown in a fifth exemplary embodiment which is substantially identical to the exemplary embodiment shown in FIG. Valve 98 instead of by sliding in the direction of the longitudinal axis A slices formed by about axes 106, 1 08 pivotable flaps, wherein the axis 106 of the intermediate valve 62 and the axis 108 which the Spϋlungsventil 74th forming part of the two-way valve 98 is assigned. Preferably, a plurality of flaps are respectively used for the intermediate valve 62 and for the scavenging valve 74 in the circumferential direction.

Fig. 6 shows a compressed gas switch, in particular a circuit breaker, according to a sixth Ausfϋhrungsbeispiel the invention. Such gas blast switches are used in particular in high-voltage switchgear.

Around the first contact 14 around a hollow cylindrical shape having a separating element 30 is arranged, wherein the one end portion 32 of the partition member 30 tapers. The free end of the tapered end portion 32 is aligned in the direction of the longitudinal axis A substantially with the free end of the first contact 14. In the circumferential direction, a stationary conductor element 33 engages around the other end region of the separating element 30, which is opposite to the tapered end portion 32 in the direction of the longitudinal axis A. A conductive connection between the conductor element 33 and the separating element 30 movable relative to the conductor element 33 is produced by a contact spring 35. The contact can be made instead of a contact spring, for example, via a sliding contact, a spiral contact, a sliding tulip or a roller contact. This contact spring 35 is inserted in a circumferential groove, which is formed radially inwardly in the free end region of the conductor element 33.

The separator 30 is part of a well-known rated current contact arrangement, not shown in the figures. The separator 30 forms a first rated current contact and is electrically connected to the first contact 1 4. The second contact 1 8 is electrically connected to a second rated current contact, not shown, and is intended to cooperate with the first rated current contact, the separating element 30, when the compressed gas switch is closed.

In the tapered end portion 32 of the separating element 30, a nozzle body 34 is arranged, wherein the nozzle body 34 protrudes from the separating element 30 in the direction of the longitudinal axis A. The nozzle body 34 is preferably made of an insulating material, such as polytetrafluoroethylene. From the end projecting from the separating element 30, the nozzle body 34 initially has a nozzle opening 36, which tapers in the direction of the longitudinal axis A towards the first contact 14 and merges into a nozzle channel 38. The nozzle channel 38 expands on the opposite side of the nozzle opening 36 to an inner diameter which is greater than an outer diameter of the contact tulip of the first contact 1 4, wherein the inner diameter is selected such that the contact fingers of the contact tulip have a sufficiently large game. The area within the Denksenkörpers 34, which lies between the contact tulip and the free end, forms an arc zone 40th

In the Dϋsenkanal 38 opens a gas channel 44 which connects the arc zone 40 with a heating chamber 46 in the interior of the separating element 30. This

Gas channel 44 is intended for one, quenching gas, which by a

Arc is heated to lead from the arc zone 40 in the heating chamber 46. On the other hand, the gas channel 44 is intended to lead quenching gas from the heating chamber 46 for blowing the arc burning in the arc zone 40 into the arc zone 40. Typically, the

Boiler room 46 a constant volume.

The heating chamber 46 is limited in the radial direction by the separating element 30. In the direction of the nozzle opening 36, the heating chamber 46 is likewise delimited by the separating element 30 as well as by the nozzle body 34. In the opposite direction to the nozzle opening 36 of the heating chamber 46 is bounded by an intermediate wall-like intermediate member 48. The first contact element 14 is guided tightly through the intermediate element 48. The intermediate element 48 is preferably held on the separating element 30 in a form-fitting manner. It may also be positively secured to the first contact 1 4.

By means of the intermediate element 48, an interior of the separating element 30 is subdivided into the heating space 46 and into a compression space 52. The interior of the separating element 30 - the heating chamber 46 and the compression space 52 - together form a blowing volume 54. The compression space 52 is bounded on the side opposite the intermediate element 48 by a piston 56, which is arranged stationary in the present case. The piston 56 is part of a cylinder-piston arrangement, wherein the cavity of this cylinder-piston assembly is formed by the compression space 52. The piston 56 has a passage opening for the first contact 14. Between the piston 56 and the first contact 1 4, a seal 80 is inserted into a circumferential groove in the piston to seal a gap between the first contact 14 and the piston 56. Furthermore, the seal 80 also forms a guide for the first contact 1 4. The piston 56 is sealed against the separating element 30 by means of a further seal 82, which is inserted into a further circumferential groove in the piston 56.

In the radial direction, a flow-through opening 64 'leads from the

Compression space 52 in a radially outwardly adjacent to the separator 30 low-pressure space 72. The low-pressure space 72 surrounds the rated current contact arrangement. In the low pressure chamber 72 prevails at least approximately during a switching operation of the gas pressure switch 1 0 a constant gas pressure, which is preferably in the range of 3-7 bar.

As shown in FIG. 6, according to the invention, the flow-through opening 64 'can not be closed by a valve. In other words, the flow-through opening is a non-closable flow-through opening 64 ', through which quenching gas can flow as well as can flow. The non-closable flow-through opening 64 'leads in the radial direction with respect to the longitudinal axis A through the separating element 30. Consequently, a flow direction through the non-closable flow opening 64 'extends in the radial direction. Due to the small diameter of the flow-through opening 64 ', the quenching gas flow can be controlled by the non-closable flow-through opening 64', in particular with an overpressure in the compression space 52 relative to the low-pressure space 72. Consequently, especially when the first contact 1 4 is separated from the second contact 1 8, at the same time the volume of the compression chamber 52 is reduced, quenching gas from the compression chamber 52 in the low pressure chamber 72 through the non-closable flow-through 64 'flow.

As shown in FIG. 6, a flow-through opening 64 forming a flushing passage 66 can be arranged parallel to the flow-through opening 64 ', which can not be closed. This in turn connects the low-pressure chamber 72 with the blowing volume 54, in particular with the compression chamber 52. The flushing passage 66 can be closed by means of a flushing valve 74 designed as a check valve so that the flushing valve 74 opens and otherwise closes when the vacuum chamber 72 is under reduced pressure in the compression chamber 52. The low-pressure space 72 is bounded by an envelope, not shown, of the gas pressure switch and connected to the exhaust volume 58 via a gas return duct.

Of course, a plurality of flushing passages 66 can also be provided which can each be closed by means of a flushing valve 74. Likewise, a plurality of non-closable flow openings 64 'may be provided.

The gas pressure switch shown in Fig. 6 operates when opening the gas pressure switch as follows. First, the rated current contact arrangement is opened. Subsequently, the contact arrangement formed by the first Kantakt 1 4 and the second contact 1 8 is separated, which ignites an arc in the arc zone 40 because of the current flow through the contact arrangement. As a result, quenching gas is heated. This initially flows through the gas channel 44 in the heating chamber 46. When opening the contact arrangement is also reduced by the movement of the separating element 30 together with the first contact 14 in the direction of the longitudinal axis A away from the second contact 1 8, the compression space 52, whereby the gas pressure in this is rising. If the gas pressure in the compression chamber 52 is greater than in the heating chamber 46, opens the intermediate valve 62, whereby quenching gas flows through the channel 60 from the compression chamber 52 into the heating chamber 46 and further increases the gas pressure in this. As soon as the gas pressure in the arc zone 40 decreases, quenching gas flows from the heating chamber 46 through the gas channel 44 into the arc zone 40 and inflates the arc, which is thereby extinguished.

However, if due to a strong current flow, for example, triggered by a ground fault, the gas pressure in the heating chamber 46 rapidly increases to a high value, the situation may occur that in the heating chamber 46 during the separation of the contact arrangement, the intermediate valve 62 remains closed, or at least closed over a longer period of time during the separation process. As a result, the extinguishing gas from the compression chamber 52 does not flow into the heating chamber 46. However, the quenching gas can flow through the non-closable flow-through opening 64 'into the low-pressure space 72. In this case, there is a greater pressure in the compression chamber 52 than in the low-pressure chamber 72 and in the heating chamber 46 there is a greater pressure than in the compression chamber 52. Since in the low-pressure chamber 72, in particular during the separation process, an at least almost constant gas pressure prevails, the maximum pressure in the compression chamber 52nd be defined by the clear diameter of the non-closable flow-through opening 64 '. It can thereby be achieved that a force necessary for opening the contact arrangement, in particular for retracting the separating element 30 together with the first contact 14 into the conductor element 33, does not exceed a maximum force. Thereby, the drive arrangement can be designed such that the contact arrangement can be reliably separated even at high current flow.

The extinguishing gas used to blow the arc in the arc zone 40 flows from the heating chamber 46 through the gas channel 44 to the arc zone 40 and then on the one hand through the flow channel 59 in the exhaust volume 58 and on the other hand through the nozzle opening 36 from. In the exhaust volume 58, the hot quenching gas is cooled. A gas exchange between the exhaust volume 58 and the low pressure space 72 can take place via a not shown gas recirculation.

When closing the contact arrangement, the volume of the increased

Compression space 52, which creates a negative pressure in this compared to the low-pressure chamber 72 as well as to the heating chamber 46. On the one hand, extinguishing gas flows through the non-closable flow-through opening 64 'into the compression space 52. In addition, the scavenging valve 74 opens, which releases the scavenging passage 66 for the flow of quenching gas from the low-pressure space 72 into the compression space 52. As soon as the gas pressure in the compression volume 52 rises above the gas pressure in the low-pressure space 72, the purging valve 74 closes.

In Fig. 7, a further Ausfϋhrungsbeispiel the inventive gas pressure switch is shown. Essentially, this exemplary embodiment corresponds to the compressed-gas switch 10 shown in FIG. 6. Only the differences are discussed here.

In this embodiment, the separating element 30 has only the non-closable flow-through opening 64 '. Preferably, 4-8 non-closing flow openings 64 'are formed on the separating element 30. The non-closable flow-through openings 64 'can also be formed as slots.

The intermediate element 48 shown in Fig. 7 is integrally formed with the tube 1 2 of the first contact 14. Of course, the intermediate piece and the tube 1 2 may be formed consisting of several individual elements.

The piston 56 has a scavenging passage 66 'which, according to the scavenging passage 66 described in connection with FIG. 6, can be closed by means of a scavenging valve 74' designed as a check valve. The purge passage 66 'leads from the exhaust volume 58 into the compression space 52. By arranged on the first contact 1 4 intermediate element 48 of the channel 60 is performed in the direction of the longitudinal axis A. Preferably, the intermediate element 48 has a plurality of circumferentially regularly arranged channels 60. The channel 60 or the channels 60 is / are closable by means of a valve plate of the intermediate valve 62. The valve plate is preferably in turn formed as a circular ring disk.

The conductor element 33 is designed to be elongated in the direction of the longitudinal axis A in comparison with the exemplary embodiment shown in FIG. Between the partition member 30 and the extended portion of the partition member 30, a gap 94 is formed. The non-closable flow-through opening 64 'opens into this intermediate space 94. From the intermediate space 94, a channel 96 leads into the low-pressure space 72.

LIST OF REFERENCE NUMBERS

1 0 Gas pressure switch

1 2 pipe

1 4 first contact

1 6 pen

1 8 second contact

20 free end

30 separating element

32 end area

33 conductor element

34 body

35 contact spring

36 nozzle opening

38 Dϋsenkanal

40 arc zone

44 gas channel

46 boiler room

48 intermediate element

52 compression space

54 blowing volume

56 pistons

58 exhaust volumes

59 flow channel

60 channel

62 intermediate valve

64 flow opening

64 'non-closable flow-through opening 66, 66' Spels passage 68 overpressure passage

72 low pressure room

74, 74 'Spϋlungsventil

76 Pressure relief valve 80, 82 Seal

86 ring channel

87 connection channel

88 wall

90 annular disc 92 springs

94 gap

96 channel

98 two-way valve

1 00 holes 1 02 guide element

1 04 valve disc

1 06, 1 08 axes

A longitudinal axis

Claims

PATENT APPLICATIONS

1 . Gas blast switch with a first contact (1 4) and a second contact (1 8), which is intended to be with the first

Contact (1 4) to produce an electrically conductive, re-separable connection, wherein the first contact (1 4) and the second contact (1 8) relative to each other along a longitudinal axis (A) are movable, with a blowing volume (54; 52, 46 ), which is fluidly connected to an arc zone (40) and is intended to allow a pressure build-up to blow an arc with quenching gas, an exhaust volume (58), which is intended to receive and cool hot lane, through a separating element (58). 30) from the blowing volume (54) separated low pressure chamber (72) in which at least approximately during a switching operation, a constant gas pressure prevails, characterized by a gas exchange permitting, non-closing flow opening (64 ') between the low pressure chamber (72) and the blowing volume (54; 52, 46) through a portion of the separating element (30), the void volume (54; 52, 46) in the radial direction with respect to the longitudinal axis (A) v in the low-pressure chamber (72).

2. Gas-blast switch according to claim 1, characterized in that a flow direction through the non-closable flow-through opening (64 ') substantially in the radial direction runs.

3. Gas-blast switch according to claim 1 or 2, characterized in that in the blowing volume (54, 46, 52) an intermediate element (48) is arranged, which the blowing volume

(54, 46, 52) into a directly connected to the arc zone heating chamber (46) and a compression space (52), wherein the non-closable flow opening (64 ') in the compression space (52) opens.

4. Gas-blast switch according to one of claims 1 to 3, characterized in that it comprises a further, closable flow-through opening (66), and in or on the further flow-through opening (66) designed as a check valve flushing valve (74) is arranged, which is open if the gas pressure on the side of the low-pressure chamber (72) is higher.

5. gas blast switch with a first contact (1 4) and a second contact (1 8), which is intended to be with the first

Contact (1 4) to produce an electrically conductive, re-separable connection, wherein the first contact (1 4) and the second contact (1 8) relative to each other along a longitudinal axis (A) are movable, with a blowing volume (54; 52, 46 ), which is fluidly connected to an arc zone (40) and is intended to allow a pressure build-up to blow an arc with quenching gas, an exhaust volume (58), which is intended to receive and cool hot lane, through a separating element (58). 30) of blowing volume (54) separated low-pressure chamber (72) in which there is a constant gas pressure at least approximately during a switching operation, wherein the gas pressure switch a gas exchange permitting flow opening (64, 66, 68) between the low pressure chamber (72) and the blowing volume

(54, 52, 46) through a region of the separating element (30) therethrough, which separates the blowing volume (54, 52, 46) in the radial direction with respect to the longitudinal axis (A) from the low-pressure chamber (72), characterized in that or to the

Throughflow (64, 66) designed as a check valve flush valve (74) is arranged.

6. Gas-blast switch according to claim 5, characterized in that the flush valve (74) is open, if the gas pressure on the side of the low-pressure chamber (72) is higher.

7. Gas-blast switch according to claim 5 or 6, characterized in that the flush valve (74) and a pressure relief valve (76) in the same or at the same

Throughflow (64) are arranged, in particular, the flush valve (74) and the pressure relief valve (76) are formed together as a two-way valve (98).

8. Gas-blast switch according to one of claims 5 or 6, characterized in that the compressed gas switch has a further flow-through opening (64) and that in or on the further flow-through opening (64, 68) a pressure relief valve (76) is arranged, which at a defined negative pressure the side of the low pressure chamber (72) opens.

9. Gas blast switch according to one of claims 5 to 8, characterized in that the pressure relief valve (76) and / or the Spϋlungsventil (74) in the radial direction between the

Separating element (30) and the longitudinal axis (A) of

Compressed gas switch are arranged or is.

1 0. Gas-blast switch according to one of claims 5 to 9, characterized in that in the blowing volume (54, 46, 52) a

Intermediate element (48) is arranged, which is the blowing volume

(54, 46, 52) into a directly connected to the arc zone heating chamber (46) and a compression chamber (52), wherein the throughflow opening (64, 66) and / or the further flow-through opening (64, 68) in the compression space

(52) opens.

1 1. Gas-blast switch according to one of claims 1 to 1 0, characterized in that the separating element (30) is movable, wherein this when opening and closing the separable

Connection is moved.

1 2. Gas-blast switch according to one of claims 1 to 1 1, characterized in that the flow-through opening (64, 66, 68) opens directly into the low-pressure chamber (72).

1 3. Gas-blast switch according to one of claims 1 to 1 2, characterized in that the flow-through opening (66, 68) as

Connecting channel (87) is formed, said connecting channel (87) preferably together with the channel (60) is formed in a common assembly, and the connecting channel (87) preferably by means of a valve (66, 68) or a two-way valve (98) and the channel also preferably by means of a valve (62) are closable.

1 4. Gas-blast switch according to one of claims 1 to 1 3, characterized in that the flow-through opening (66) and and the channel (60) are formed in a common assembly.

1 5. Gas-blast switch according to one of claims 1 to 1 4, characterized in that the exhaust volume (58) in the longitudinal direction (A) to the blowing volume (54, 52, 46) on the arc zone (40) opposite side adjacent and a piston (56) a cylinder-piston assembly the

Blasvolumen tightly separated from the exhaust volume (58), wherein the separating element (30) is formed by the cylinder of the cylinder-piston assembly.

1 6. Gas-blast switch according to one of claims 1 to 1 5, characterized in that the exhaust volume (58) via a gas return to the low-pressure chamber (72) is connected.

1 7. Gas-blast switch according to one of claims 1 to 1 6, characterized in that the low-pressure space (72) with respect to a longitudinal axis (A) of the gas pressure switch radially outside the blast volume (54, 52, 46) is arranged.

1 8. Gas-blast switch according to one of claims 1 to 1 7, characterized in that between the compression chamber (52) and Exhaust volume (58) a Spülungsdurchlass (66 ') is formed, which is closed by means of a designed as a check valve flush valve (74'), wherein the flush valve (74 ') is closed at an overpressure in the compression chamber (52) relative to the exhaust volume (58) ,

9. Gas-blast switch according to one of claims 1 to 1 8, characterized in that between the compression space (52) and the heating chamber (46) is a gas flow from

Compression chamber (52) in the heating chamber (46) ermöglichender channel (60) is formed, which is preferably closed by means of a designed as a check valve intermediate valve (62), wherein the intermediate valve (62) at an overpressure in Heizrau m (46) relative to the compression volume

(52) concludes.