CA2263881C - A hermetically sealed vacuum load interrupter switch with flashover protection features - Google Patents
A hermetically sealed vacuum load interrupter switch with flashover protection features Download PDFInfo
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- CA2263881C CA2263881C CA002263881A CA2263881A CA2263881C CA 2263881 C CA2263881 C CA 2263881C CA 002263881 A CA002263881 A CA 002263881A CA 2263881 A CA2263881 A CA 2263881A CA 2263881 C CA2263881 C CA 2263881C
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- Prior art keywords
- sleeve
- load
- interrupter switch
- vacuum interrupter
- load interrupter
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/662—Housings or protective screens
- H01H33/66207—Specific housing details, e.g. sealing, soldering or brazing
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/662—Housings or protective screens
- H01H33/66207—Specific housing details, e.g. sealing, soldering or brazing
- H01H2033/6623—Details relating to the encasing or the outside layers of the vacuum switch housings
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/666—Operating arrangements
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- High-Tension Arc-Extinguishing Switches Without Spraying Means (AREA)
- Electrophonic Musical Instruments (AREA)
- Keying Circuit Devices (AREA)
- Axle Suspensions And Sidecars For Cycles (AREA)
- Gas-Insulated Switchgears (AREA)
- Oscillators With Electromechanical Resonators (AREA)
- Power Steering Mechanism (AREA)
- Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
- Thermally Actuated Switches (AREA)
- Electric Clocks (AREA)
Abstract
The invention concerns a load interrupter switch (I) for voltages in the kV
range, with a vacuum interrupter chamber (2) which is surrounded in a gap-free manner by a sleeve (4) formed from elastomer material having high dielectric strength. The sleeve (4) is in turn clamped by the two halves (11 and 12) of the housing of the load interrupter switch (1). In this way, external flashover of the high voltage between the end plates (24 and 25) of the vacuum interrupter chamber (2) is effectively prevented during switching operations without the need for liquid or gaseous media. In this way, in contrast to conventional load interrupter switches, complicated monitoring is unnecessary and the load interrupter switch is not harmful to the environment.
range, with a vacuum interrupter chamber (2) which is surrounded in a gap-free manner by a sleeve (4) formed from elastomer material having high dielectric strength. The sleeve (4) is in turn clamped by the two halves (11 and 12) of the housing of the load interrupter switch (1). In this way, external flashover of the high voltage between the end plates (24 and 25) of the vacuum interrupter chamber (2) is effectively prevented during switching operations without the need for liquid or gaseous media. In this way, in contrast to conventional load interrupter switches, complicated monitoring is unnecessary and the load interrupter switch is not harmful to the environment.
Description
Description A Hermetically Sealed Vacuum Load Interrupter Switch with Flashover Protection Features The invention relates to a load interrupter switch in accordance with the preamble of Claim 1.
Such load interrupter switches are known, for example, as switch-disconnectors in railway operations.
In this case, in the closed position the vacuum interrupter chamber is connected electrically in parallel, together with the switching mechanism accommodated in an insulating housing, to the traction circuit designed for the full nominal equipment current. During disconnection, the main contacts firstly open when de-energized and in the process commutate the current onto the series circuit, connected in parallel, of the vacuum interrupter chamber and auxiliary switching point, which has an actuating fork. As soon as the main contacts have moved apart far enough from one another, the vacuum interrupter chamber is quickly actuated via a tilting mechanism, a d the breaking arc occurring in the interior of the interrupter chamber is reliably extinguished at the first current zero without appearing externally.
However, it has proved in practice that the vacuum interrupters or interrupter chambers used have la relatively large dimensions and are attended by high production costs. Consequently, for some time use has been made of vacuum interrupter chambers of a lower voltage series than that for which the switche is designed. It is therby possible to reduce both the dimensions and he production costs, the active part in the vacuum interrupter chamber generally permitting such use.
However, the reduction in overall size is also attended by reduction in the spacing of the metallic end plates of the housing of the vacuum interrupter chamber.
The external insulation, which is stressed during and after the disconnection, is, however, therefore insufficient in the case of free air in the surroundings.
In order to solve this problem, the vacuum interrupter chambers are arranged in a medium of higher dielectric strength. It is possible in this case to apply, inter alia, insulating oil, for example mineral oil or silicone oil, various esters or an insulating gas such as, for example, sulphurhexafluoride (SF6). These media displace the air in the surroundings of the vacuum interrupter chambers and, since they have a high dielectric strength, an external flashover is prevented.
However, these media have the disadvantage of not being unobjectionable with regard to their environmental compatibility. Since such load interrupter switches have been in use over many years, leaks due to ageing of components an don the basis of external influences cannot be completely ruled out. It is therefore possible in some circumstances for medium to escape into the surroundings.
2a A further disadvantage of such media is that they require continuous monitoring. In the case of the use of insulating oil it is necessary, for example, to check the oil level, and since such load interrupter switches are installed on high masts in most cases of use, a corresponding outlay is required here. The situation is similar in the case of insulating gas, in the case of which the pressure must be checked.
Furthermore, it is also known to improve the external insulation of the vacuum interrupter chambers by encapsulation using epoxy resin, for example.
Such load interrupter switches are known, for example, as switch-disconnectors in railway operations.
In this case, in the closed position the vacuum interrupter chamber is connected electrically in parallel, together with the switching mechanism accommodated in an insulating housing, to the traction circuit designed for the full nominal equipment current. During disconnection, the main contacts firstly open when de-energized and in the process commutate the current onto the series circuit, connected in parallel, of the vacuum interrupter chamber and auxiliary switching point, which has an actuating fork. As soon as the main contacts have moved apart far enough from one another, the vacuum interrupter chamber is quickly actuated via a tilting mechanism, a d the breaking arc occurring in the interior of the interrupter chamber is reliably extinguished at the first current zero without appearing externally.
However, it has proved in practice that the vacuum interrupters or interrupter chambers used have la relatively large dimensions and are attended by high production costs. Consequently, for some time use has been made of vacuum interrupter chambers of a lower voltage series than that for which the switche is designed. It is therby possible to reduce both the dimensions and he production costs, the active part in the vacuum interrupter chamber generally permitting such use.
However, the reduction in overall size is also attended by reduction in the spacing of the metallic end plates of the housing of the vacuum interrupter chamber.
The external insulation, which is stressed during and after the disconnection, is, however, therefore insufficient in the case of free air in the surroundings.
In order to solve this problem, the vacuum interrupter chambers are arranged in a medium of higher dielectric strength. It is possible in this case to apply, inter alia, insulating oil, for example mineral oil or silicone oil, various esters or an insulating gas such as, for example, sulphurhexafluoride (SF6). These media displace the air in the surroundings of the vacuum interrupter chambers and, since they have a high dielectric strength, an external flashover is prevented.
However, these media have the disadvantage of not being unobjectionable with regard to their environmental compatibility. Since such load interrupter switches have been in use over many years, leaks due to ageing of components an don the basis of external influences cannot be completely ruled out. It is therefore possible in some circumstances for medium to escape into the surroundings.
2a A further disadvantage of such media is that they require continuous monitoring. In the case of the use of insulating oil it is necessary, for example, to check the oil level, and since such load interrupter switches are installed on high masts in most cases of use, a corresponding outlay is required here. The situation is similar in the case of insulating gas, in the case of which the pressure must be checked.
Furthermore, it is also known to improve the external insulation of the vacuum interrupter chambers by encapsulation using epoxy resin, for example.
However, ageing processes can lead in this case to an air gap and thus to an external flashover of the vacuum interrupter chamber in the region between the epoxy resin casing and the outer housing. Such ageing processes give rise, for example, to stress cracks due to after-shrinkage of the cast resin jacket, embrittlement due to loss of effectiveness by flexibilizers which were used during encapsulation, or the formation of gaps by detachment of the resin jacket from the outer housing of the vacuum interrupter chamber as a consequence of differential material expansion during frequent alternating stress between hot and cold. This risk cannot therefore be entirely removed. A further disadvantage resides in the fact that such an encapsulated vacuum interrupter chamber can be accessed in the case of dismounting only by destroying the enclosure.
The embodiments known so far are therefore complicated and can be employed only conditionally for universal use, for example on overhead line towers, or are frequently rejected because of possible endangerment of the environment.
Document FR-2 698 481 A1 discloses a load interrupter switch having a vacuum interrupter chamber, an electrically insulating body made from silicone being arranged between the housing of the vacuum interrupter chamber and an outer housing. Said silicone body is tubular and has elastically deformable ribs either on the outside or on the inside. It is made so that it simultaneously makes intimate contact with the outer surface of the interrupter chamber housing and the inner surface of the outer housing. The aim here is to achieve an absence of a gap in order to avoid an electric flashover. In addition, it is possible during mounting to introduce an insulating grease in the region between the interrupter chamber housing and the inside of the silicone body, while the ribs on the AMENDED SHEET
The embodiments known so far are therefore complicated and can be employed only conditionally for universal use, for example on overhead line towers, or are frequently rejected because of possible endangerment of the environment.
Document FR-2 698 481 A1 discloses a load interrupter switch having a vacuum interrupter chamber, an electrically insulating body made from silicone being arranged between the housing of the vacuum interrupter chamber and an outer housing. Said silicone body is tubular and has elastically deformable ribs either on the outside or on the inside. It is made so that it simultaneously makes intimate contact with the outer surface of the interrupter chamber housing and the inner surface of the outer housing. The aim here is to achieve an absence of a gap in order to avoid an electric flashover. In addition, it is possible during mounting to introduce an insulating grease in the region between the interrupter chamber housing and the inside of the silicone body, while the ribs on the AMENDED SHEET
outside are compressed at least slightly in order to produce a seal.
German Utility Model G 93 14 754 U1 has disclosed a vacuum interrupter having an encapsulation resistant to internal pressure. The encapsulation of this vacuum interrupter comprises an inner coating made from a hard foam plastic, and an outer burst-proof jacket. The inner coating, preferably consisting of a polyurethane foam, is uniformly porous, in order, in accordance with the teaching of this document, to permit the best possible thermal insulation, so that in the case of failure a temperature sufficient to ignite the surrounding gas cannot be reached. The burst-proof jacket is constructed as a wound body, and comprises threads or strips which are impregnated with a cured plastic. It is constructed bearing tightly against the foam coating and dimensioned such that it can absorb the bursting force which occurs in the event of a fault inside the vacuum interrupter.
In the case of this prior art, as well, sheathing of the interrupter includes a permanently foamed plastic material whose properties can be impaired by ageing. In particular, embrittlement or detachment of the foam coating from the outer housing of the interrupter can occur. In addition, this encapsulated vacuum interrupter can be dismounted only given destruction of the enclosure.
It is therefore an object of an aspect of the invention to create a load interrupter switch which is reliably capable of use over a long time without monitoring and can, in addition, be dismounted.
According to one aspect of the invention, there is provided a load interrupter switch for voltages above -4a-1 kV, having a vacuum interrupter chamber whose contacts are closed or opened by means of a switching mechanism, the vacuum interrupter chamber having a housing with metallic end plates which encloses the switching contacts situated in the vacuum, and a cylindrical housing middle part made from an electrically insulating material, which housing is surrounded by a coating which is made from a dielectric material and grips the edges of the two end plates behind, it being the case that provided on the outside of the dielectric coating is a jacket of complementary construction, which is made from insulating material and pressurizes the outer circumference of the dielectric coating, characterized in that the dielectric coating is formed by a prefabricated sleeve which consists of an elastomeric material of high dielectric strength which is pressed against the housing without a __ ,___ _ _______.___ ,_,.....__.,... ....~..r,~.... ,~ ~~..,o ~~,.vor.
Furthermore, impairment of the environment by escaping media is thereby avoided, as a result of which the load interrupter switch according to the invention can be used, for example, without objection in protected 5 water gathering grounds as well. A continuously useable load interrupter switch which can be universally employed is thereby provided.
A further advantage resides in that mounting the load interrupter switch according to the invention is substantially simplified. Thus, the construction with a prefabricated sleeve 5a permits preassembly of the arrangement, which means there is no need for outlay on final mounting or filling, for example high up on the mast. Since no liquid or gaseous medium is handled, there is a substantial simplification in the complexity of transporting and installing the load interrupter switch according to the invention.
The load interrupter switch according to the invention is at the same time simple to produce and can be dismounted if required. In addition, the space requirement and the costs for the vacuum interrupter chamber can be kept low.
It is also advantageous when, on the outside of the sleeve, a pressure housing of complementary construction is provided, which is made from insulating material and pretensions the outer circumference of the sleeve in the elastic region. The result of this, on the one hand, is that the sleeve presses firmly against the vacuum interrupter chamber, and further that no air gap which could permit an external flashover is produced on the outer circumference of the sleeve. The possible path length for an external flashover is virtually no longer possible. Safe working conditions and the reliability of the load interrupter switch are thereby further increased. Furthermore, the vacuum interrupter chamber is thereby centred and fixed in the pressure housing.
Advantageous developments of the invention follow from the feature s of the subclaims.
German Utility Model G 93 14 754 U1 has disclosed a vacuum interrupter having an encapsulation resistant to internal pressure. The encapsulation of this vacuum interrupter comprises an inner coating made from a hard foam plastic, and an outer burst-proof jacket. The inner coating, preferably consisting of a polyurethane foam, is uniformly porous, in order, in accordance with the teaching of this document, to permit the best possible thermal insulation, so that in the case of failure a temperature sufficient to ignite the surrounding gas cannot be reached. The burst-proof jacket is constructed as a wound body, and comprises threads or strips which are impregnated with a cured plastic. It is constructed bearing tightly against the foam coating and dimensioned such that it can absorb the bursting force which occurs in the event of a fault inside the vacuum interrupter.
In the case of this prior art, as well, sheathing of the interrupter includes a permanently foamed plastic material whose properties can be impaired by ageing. In particular, embrittlement or detachment of the foam coating from the outer housing of the interrupter can occur. In addition, this encapsulated vacuum interrupter can be dismounted only given destruction of the enclosure.
It is therefore an object of an aspect of the invention to create a load interrupter switch which is reliably capable of use over a long time without monitoring and can, in addition, be dismounted.
According to one aspect of the invention, there is provided a load interrupter switch for voltages above -4a-1 kV, having a vacuum interrupter chamber whose contacts are closed or opened by means of a switching mechanism, the vacuum interrupter chamber having a housing with metallic end plates which encloses the switching contacts situated in the vacuum, and a cylindrical housing middle part made from an electrically insulating material, which housing is surrounded by a coating which is made from a dielectric material and grips the edges of the two end plates behind, it being the case that provided on the outside of the dielectric coating is a jacket of complementary construction, which is made from insulating material and pressurizes the outer circumference of the dielectric coating, characterized in that the dielectric coating is formed by a prefabricated sleeve which consists of an elastomeric material of high dielectric strength which is pressed against the housing without a __ ,___ _ _______.___ ,_,.....__.,... ....~..r,~.... ,~ ~~..,o ~~,.vor.
Furthermore, impairment of the environment by escaping media is thereby avoided, as a result of which the load interrupter switch according to the invention can be used, for example, without objection in protected 5 water gathering grounds as well. A continuously useable load interrupter switch which can be universally employed is thereby provided.
A further advantage resides in that mounting the load interrupter switch according to the invention is substantially simplified. Thus, the construction with a prefabricated sleeve 5a permits preassembly of the arrangement, which means there is no need for outlay on final mounting or filling, for example high up on the mast. Since no liquid or gaseous medium is handled, there is a substantial simplification in the complexity of transporting and installing the load interrupter switch according to the invention.
The load interrupter switch according to the invention is at the same time simple to produce and can be dismounted if required. In addition, the space requirement and the costs for the vacuum interrupter chamber can be kept low.
It is also advantageous when, on the outside of the sleeve, a pressure housing of complementary construction is provided, which is made from insulating material and pretensions the outer circumference of the sleeve in the elastic region. The result of this, on the one hand, is that the sleeve presses firmly against the vacuum interrupter chamber, and further that no air gap which could permit an external flashover is produced on the outer circumference of the sleeve. The possible path length for an external flashover is virtually no longer possible. Safe working conditions and the reliability of the load interrupter switch are thereby further increased. Furthermore, the vacuum interrupter chamber is thereby centred and fixed in the pressure housing.
Advantageous developments of the invention follow from the feature s of the subclaims.
Owing to the fact that the dimensions of the sleeve are selected such that the sleeve applies pretensioning to the vacuum interrupter chamber, the creation of an air gap between the sleeve and the housing of the vacuum interrupter chamber is reliably prevented. Consequently, the relatively large dimensional tolerances of the vacuum interrupter chamber can also be compensated. The reliability of the load interrupter switch is thereby further increased.
Furthermore, sealing of the pressure housing with respect to external influences is achieved when the sleeve has at least one sealing bead which runs in the axial direction of the pressure housing and comes to lie in the mounting joint of the pressure housing.
The consequence of this is reliably to avoid the possibility of dirt and in particular water, for example, penetrating into the pressure housing. Failure of the load interrupter switch can thus be effectively avoided. Furthermore, the unipartite construction of the sleeve with the sealing bead facilitates the mounting of the arrangement.
If, in addition, the sealing bead has a thickened part which can be pinched in the mounting joint of the pressure housing, the reliability of this seal on the pressure housing is further increased.
The risk of an external flashover is still further reduced by virtue of the fact that circumferential shields are provided which project on the outer circumference of the sleeve in a fashion essentially parallel to the end plates.
AMENDED SHEET
F
6a It is further advantageous when the sleeve has at least one cut-out for holding sleeve material displaced during the pressure loading. The result of this is that the sleeve bears cleanly against the circumferential surface of the vacuum interrupter chamber without the sleeve being damaged by the pressure forces applied. The reliability of the load interrupter switch i c thoroh~r fmrt-hAr i nrraacar~
_ ) _ The at least one cut-out is advantageously constructed as a circumferential annular groove in the inner periphery of the sleeve. A uniform pressure distribution over the entire circumference of the vacuum interrupter chamber is thereby achieved.
If the sleeve is provided with at least one pocket on at least one end face in the region of at least one end plate, it is possible for the length of the vacuum interrupter chamber to be set in the mounted state without damage to the material of the sleeve, since said material can escape into the at least one pocket. The reliability of the sleeve, and thus the operational reliability of the load interrupter switch is thereby increased.
If the at least one pocket is, moreover, constructed annularly, the result is a uniform distribution of the pressure load on the end face of the sleeve.
The sleeve according to the invention is preferably made from EPDM (ethylene-propylene terpolymer) or silicone rubber, which have good elastic properties and are also incompressible. Such materials permit reliable sealing of the interface between the vacuum interrupter chamber and the sleeve and/or between the sleeve and the pressure housing of the load interrupter switch. An external flashover can thereby be reliably avoided.
By virtue of the fact that the load interrupter switch is constructed as a switch-disconnector in the case of which a visible isolating distance is arranged in series with the vacuum interrupter chamber, it is also possible to carry out visual monitoring from a relatively large distance in order to determine whether the load interrupter switch is closed.
If in the closed state of the load interrupter switch a circuit for high continuous current-carrying capacity is connected in parallel with the vacuum interrupter chamber or in parallel with the series circuit of the vacuum interrupter chamber/visible isolating distance, the vacuum interrupter is relieved when the load interrupter switch (switch-disconnector) is in the closed state. This has the advantage that the existing high voltages are applied to the vacuum interrupter chamber only during the switching operations. In this case, a continuous current can be conducted which is higher than the rated current of the interrupter chamber or the series circuit of the vacuum interrupter chamber and visible isolating distance. The service life of the load interrupter switch is thereby substantially increased.
The invention is explained below in more detail in an exemplary embodiment with the aid of the figures of the drawing, in which:
Fig. 1 shows a sectional representation of a load interrupter switch according to the invention, it being the case that a section in the parting plane of the pressure housing is represented on the left-hand side of the main axis, and a section in another plane through a half housing of the pressure housing is represented to the right of the main axis; and Fig. 2 shows a simplified sectional representation in accordance with the line A-A in Fig. 1.
In accordance with the representation in the figures, a load interrupter switch 1 has a pressure housing with two half housings 11 and 12 which are constructed from insulating material and in an essentially mirror-symmetrical fashion. Arranged in the half housings 11 and 12 are, inter alia, a vacuum interrupter chamber 2 and a switching mechanism 3. The mode of arrangement and the functioning of the vacuum interrupter chamber 2 and the switching mechanism correspond to the known embodiments, for which reason a detailed explanation is dispensed with in this connection. What is essential is that in the interior the vacuum interrupter chamber 2 has switching contacts which are closed or opened by the switching mechanism 3. For this purpose, the switching mechanism 3 is _g_ constructed with an eccentric actuating element 31 which acts on a moveable contact 21 of the vacuum interrupter chamber 2.
In addition to the moveable contact 21, the vacuum interrupter chamber 2 has a stationary contact 22 which is arranged opposite the moveable contact 21.
The vacuum interrupter chamber 2 further has a housing 23 which is provided with metallic end plates 24 and 25 which seal a cylindrical housing middle part 26. The housing middle part 26 is produced from electrically insulating material. Prevailing inside the vacuum interrupter chamber 2 is a high vacuum which ensures reliable are interruption in the case of disconnection, and reliable voltage stability in the disconnected state.
In order to ensure that no external flashover of the voltage occurs between the end plates 24 and 25 of the vacuum interrupter chamber 2, a sleeve 4 made from EPDM (ethylene-propylene terpolymer) is arranged around the vacuum interrupter chamber 2. This sleeve 4 is constructed in this case in such a way that it embraces the edges of the two end plates 24 and 25 of the vacuum interrupter chamber 2. Furthermore, the dimensions of the sleeve 4 are selected such that tolerance deviations in the vacuum interrupter chamber 2 can be compensated, and the sleeve 4 nevertheless bears under pretensioning against the circumferential surface of the vacuum interrupter chamber 2.
Consequently, there is no continuous air gap between the end plates 24 and 25.
The sleeve 4 is, in turn, embraced and pretensioned by the half housings 11 and 12 of the load interrupter switch 1. Because of the pretensioning, no air gap which would permit an external flashover of the voltage between the end plates 24 and 25 of the vacuum interrupter chamber 2 exists between the sleeve 4 and the mounted half housings 11 and 12.
In accordance with the representation in Fig. 1, the sleeve 4 has annularly constructed shields - 1~ -41 which are held in corresponding cut-outs in the half housings 11 and 12. The shields 41 serve in a known way to lengthen the path (leakage path) along the surface.
The sleeve 4 also has four cut-outs 42, which are arranged on the inner circumferential surface and have an annular configuration. When the half housings 11 and 12 are closed, pressure is exerted on the sleeve 4 and, since the latter is produced from an elastomeric material which is elastic but essentially incompressible, the cut-outs 42 permit the material of the sleeve 4 to escape into the free spaces thereby formed. This prevents damage to the sleeve 4 and results in good sealing of the interface between the sleeve 4 and the vacuum interrupter chamber 2.
Furthermore, an annular pocke t 43 is constructed at the end of the sleeve 4 which grips over the end plate 25 in the region of the stationary contact 22. Since vacuum interrupter chambers 2 have relatively large length tolerances, it is necessary in some circumstances to set the length and/or position of the vacuum interrupter chamber 2 in the load interrupter switch 1. In order to permit the deformation of the sleeve 4 necessary for the purpose in this end face region, the annular pocket 43 serves as a chamber for equalizing the volume of the displaced material.
In accordance with the representation in Fig. 2, the sleeve 4 further has a sealing bead 44 with a thickened part 45. These are arranged in each case on the two mounting joints of the half housings 11 and 12 of the load interrupter switch 1 for the purpose of sealing with respect to external influences. The thickened part 45 is held in this case in correspondingly constructed depressions or grooves on the joint surfaces of the half housings 11 and 12, and pinched when the half housings 11 and 12 are closed.
The sealing bead 44 with the thickened part 45 in this case has a length which corresponds essentially to the total length of the sleeve 4. However, it can also be constructed in the entire mounting j oint region of the half housings 11 and 12 in one piece with the sleeve 4 as a cord for sealing the pressure housing.
When the load interrupter switch 1 is opened in operation, the contacts 21 and 22, which are under pretensioning by springs, are released by the switching mechanism 3, with the result that they open the switching contacts in the vacuum interrupter chamber 2.
Because of the high voltage applied, which can be 45 kV, for example, depending on the application, the arrangement tends to seek a path for a possible discharge of voltage through an arc. This is not possible inside the vacuum interrupter chamber 3 because of the vacuum.
Since the sleeve 4 bears under pretensioning against the housing 23 of the vacuum interrupter chamber 2 and is connected, likewise under pretensioning, to the pressure housing of the load interrupter switch 1, there is no air gap present which would permit a voltage flashover. A flashover through the material of the sleeve 4 is likewise not possible because of the high dielectric strength of the material used for the sleeve 4. Such an external flashover is therefore prevented.
In an example of use, the load interrupter switch is used as a switch-disconnector and arranged in series with a visible isolating distance. In this arrangement, a traction circuit designed for continuous load current is connected in parallel with the vacuum interrupter chamber and an auxiliary switching point connected in series with the latter, as a result of which the vacuum interrupter is relieved with the switch-disconnector switched through. To disconnect the switch-disconnector, the first step is to open the main contact in the known way, resulting in the voltage being conducted completely across the vacuum interrupter chamber 2. Subsequently, the contacts 21 and 22 of the vacuum interrupter chamber 2 are separated and the connection is completely interrupted without an arc flashover being able to form in the load interrupter switch 1.
The invention permits further approaches to configuration in addition to the exemplary embodiment set forth here.
The dimensions and configuration of the sleeve 4 can vary, depending on the design and type of construction of the vacuum interrupter chamber 2. It is essential in each case in this regard that the sleeve 4 bears against the vacuum interrupter chamber 2 in such a way that no air gap is possible therebetween.
The sleeve 4 need not be constructed with shields 41, but can also have an outer circumferential surface which is of a different configuration or smooth if it allows the safety of the load interrupter switch 1, for example on the basis of low prevailing voltages.
In the example shown, the cut-outs 42 in the sleeve 4 have semicircular cross sections and are constructed at four points around the vacuum interrupter chamber 2. Both the configuration and number of the annular cut-outs 42 can deviate from this. Furthermore, it is also possible to provide the cut-outs 42 with an annular configuration, instead of the embodiment shown, at points on the inner circumferential surface of the sleeve 4.
The pocket 43 in the sleeve 4 can also be provided on both end faces. Moreover, the configuration and the number of pockets 43 can vary in a way similar to that in the case of the cut-outs 42.
The sleeve 4 can be used in an arbitrary way in conjunction with vacuum interrupter chambers 2, something which also includes switching elements other than switch-disconnectors. Thus, use i~ circuit-breakers and the like is also conceivable.
The pressure housing can also comprise more than two part housings, the number of the sealing beads 44 being matched to the number of the mounting joints.
Furthermore, it is also possible to provide in parallel with the vacuum interrupter chamber 2 a continuous current or primary current contact system which permits the load interrupter switch 1 to be designed for various nominal or continuous currents in conjunction with the use of a specific vacuum interrupter chamber 2.
The invention thus creates a load interrupter switch 1 for voltages in the kV range and having a vacuum interrupter chamber 2 which is embraced without a gap by a sleeve 4 constructed from elastomeric material of high dielectric strength. The sleeve 4 is, for its part, clamped by the half housings 11 and 12 of the load interrupter switch 1. In this way, an external flashover of the high voltage between the end plates 24 and 25 of the vacuum interrupter chamber 2 is effectively suppressed during the switching operation without the need for liquid or gaseous media for this purpose. As a result, by contrast with conventional load interrupter switches there is no need for a high outlay on monitoring, and the load interrupter switch is unobjectionable with regard to the environment.
Furthermore, sealing of the pressure housing with respect to external influences is achieved when the sleeve has at least one sealing bead which runs in the axial direction of the pressure housing and comes to lie in the mounting joint of the pressure housing.
The consequence of this is reliably to avoid the possibility of dirt and in particular water, for example, penetrating into the pressure housing. Failure of the load interrupter switch can thus be effectively avoided. Furthermore, the unipartite construction of the sleeve with the sealing bead facilitates the mounting of the arrangement.
If, in addition, the sealing bead has a thickened part which can be pinched in the mounting joint of the pressure housing, the reliability of this seal on the pressure housing is further increased.
The risk of an external flashover is still further reduced by virtue of the fact that circumferential shields are provided which project on the outer circumference of the sleeve in a fashion essentially parallel to the end plates.
AMENDED SHEET
F
6a It is further advantageous when the sleeve has at least one cut-out for holding sleeve material displaced during the pressure loading. The result of this is that the sleeve bears cleanly against the circumferential surface of the vacuum interrupter chamber without the sleeve being damaged by the pressure forces applied. The reliability of the load interrupter switch i c thoroh~r fmrt-hAr i nrraacar~
_ ) _ The at least one cut-out is advantageously constructed as a circumferential annular groove in the inner periphery of the sleeve. A uniform pressure distribution over the entire circumference of the vacuum interrupter chamber is thereby achieved.
If the sleeve is provided with at least one pocket on at least one end face in the region of at least one end plate, it is possible for the length of the vacuum interrupter chamber to be set in the mounted state without damage to the material of the sleeve, since said material can escape into the at least one pocket. The reliability of the sleeve, and thus the operational reliability of the load interrupter switch is thereby increased.
If the at least one pocket is, moreover, constructed annularly, the result is a uniform distribution of the pressure load on the end face of the sleeve.
The sleeve according to the invention is preferably made from EPDM (ethylene-propylene terpolymer) or silicone rubber, which have good elastic properties and are also incompressible. Such materials permit reliable sealing of the interface between the vacuum interrupter chamber and the sleeve and/or between the sleeve and the pressure housing of the load interrupter switch. An external flashover can thereby be reliably avoided.
By virtue of the fact that the load interrupter switch is constructed as a switch-disconnector in the case of which a visible isolating distance is arranged in series with the vacuum interrupter chamber, it is also possible to carry out visual monitoring from a relatively large distance in order to determine whether the load interrupter switch is closed.
If in the closed state of the load interrupter switch a circuit for high continuous current-carrying capacity is connected in parallel with the vacuum interrupter chamber or in parallel with the series circuit of the vacuum interrupter chamber/visible isolating distance, the vacuum interrupter is relieved when the load interrupter switch (switch-disconnector) is in the closed state. This has the advantage that the existing high voltages are applied to the vacuum interrupter chamber only during the switching operations. In this case, a continuous current can be conducted which is higher than the rated current of the interrupter chamber or the series circuit of the vacuum interrupter chamber and visible isolating distance. The service life of the load interrupter switch is thereby substantially increased.
The invention is explained below in more detail in an exemplary embodiment with the aid of the figures of the drawing, in which:
Fig. 1 shows a sectional representation of a load interrupter switch according to the invention, it being the case that a section in the parting plane of the pressure housing is represented on the left-hand side of the main axis, and a section in another plane through a half housing of the pressure housing is represented to the right of the main axis; and Fig. 2 shows a simplified sectional representation in accordance with the line A-A in Fig. 1.
In accordance with the representation in the figures, a load interrupter switch 1 has a pressure housing with two half housings 11 and 12 which are constructed from insulating material and in an essentially mirror-symmetrical fashion. Arranged in the half housings 11 and 12 are, inter alia, a vacuum interrupter chamber 2 and a switching mechanism 3. The mode of arrangement and the functioning of the vacuum interrupter chamber 2 and the switching mechanism correspond to the known embodiments, for which reason a detailed explanation is dispensed with in this connection. What is essential is that in the interior the vacuum interrupter chamber 2 has switching contacts which are closed or opened by the switching mechanism 3. For this purpose, the switching mechanism 3 is _g_ constructed with an eccentric actuating element 31 which acts on a moveable contact 21 of the vacuum interrupter chamber 2.
In addition to the moveable contact 21, the vacuum interrupter chamber 2 has a stationary contact 22 which is arranged opposite the moveable contact 21.
The vacuum interrupter chamber 2 further has a housing 23 which is provided with metallic end plates 24 and 25 which seal a cylindrical housing middle part 26. The housing middle part 26 is produced from electrically insulating material. Prevailing inside the vacuum interrupter chamber 2 is a high vacuum which ensures reliable are interruption in the case of disconnection, and reliable voltage stability in the disconnected state.
In order to ensure that no external flashover of the voltage occurs between the end plates 24 and 25 of the vacuum interrupter chamber 2, a sleeve 4 made from EPDM (ethylene-propylene terpolymer) is arranged around the vacuum interrupter chamber 2. This sleeve 4 is constructed in this case in such a way that it embraces the edges of the two end plates 24 and 25 of the vacuum interrupter chamber 2. Furthermore, the dimensions of the sleeve 4 are selected such that tolerance deviations in the vacuum interrupter chamber 2 can be compensated, and the sleeve 4 nevertheless bears under pretensioning against the circumferential surface of the vacuum interrupter chamber 2.
Consequently, there is no continuous air gap between the end plates 24 and 25.
The sleeve 4 is, in turn, embraced and pretensioned by the half housings 11 and 12 of the load interrupter switch 1. Because of the pretensioning, no air gap which would permit an external flashover of the voltage between the end plates 24 and 25 of the vacuum interrupter chamber 2 exists between the sleeve 4 and the mounted half housings 11 and 12.
In accordance with the representation in Fig. 1, the sleeve 4 has annularly constructed shields - 1~ -41 which are held in corresponding cut-outs in the half housings 11 and 12. The shields 41 serve in a known way to lengthen the path (leakage path) along the surface.
The sleeve 4 also has four cut-outs 42, which are arranged on the inner circumferential surface and have an annular configuration. When the half housings 11 and 12 are closed, pressure is exerted on the sleeve 4 and, since the latter is produced from an elastomeric material which is elastic but essentially incompressible, the cut-outs 42 permit the material of the sleeve 4 to escape into the free spaces thereby formed. This prevents damage to the sleeve 4 and results in good sealing of the interface between the sleeve 4 and the vacuum interrupter chamber 2.
Furthermore, an annular pocke t 43 is constructed at the end of the sleeve 4 which grips over the end plate 25 in the region of the stationary contact 22. Since vacuum interrupter chambers 2 have relatively large length tolerances, it is necessary in some circumstances to set the length and/or position of the vacuum interrupter chamber 2 in the load interrupter switch 1. In order to permit the deformation of the sleeve 4 necessary for the purpose in this end face region, the annular pocket 43 serves as a chamber for equalizing the volume of the displaced material.
In accordance with the representation in Fig. 2, the sleeve 4 further has a sealing bead 44 with a thickened part 45. These are arranged in each case on the two mounting joints of the half housings 11 and 12 of the load interrupter switch 1 for the purpose of sealing with respect to external influences. The thickened part 45 is held in this case in correspondingly constructed depressions or grooves on the joint surfaces of the half housings 11 and 12, and pinched when the half housings 11 and 12 are closed.
The sealing bead 44 with the thickened part 45 in this case has a length which corresponds essentially to the total length of the sleeve 4. However, it can also be constructed in the entire mounting j oint region of the half housings 11 and 12 in one piece with the sleeve 4 as a cord for sealing the pressure housing.
When the load interrupter switch 1 is opened in operation, the contacts 21 and 22, which are under pretensioning by springs, are released by the switching mechanism 3, with the result that they open the switching contacts in the vacuum interrupter chamber 2.
Because of the high voltage applied, which can be 45 kV, for example, depending on the application, the arrangement tends to seek a path for a possible discharge of voltage through an arc. This is not possible inside the vacuum interrupter chamber 3 because of the vacuum.
Since the sleeve 4 bears under pretensioning against the housing 23 of the vacuum interrupter chamber 2 and is connected, likewise under pretensioning, to the pressure housing of the load interrupter switch 1, there is no air gap present which would permit a voltage flashover. A flashover through the material of the sleeve 4 is likewise not possible because of the high dielectric strength of the material used for the sleeve 4. Such an external flashover is therefore prevented.
In an example of use, the load interrupter switch is used as a switch-disconnector and arranged in series with a visible isolating distance. In this arrangement, a traction circuit designed for continuous load current is connected in parallel with the vacuum interrupter chamber and an auxiliary switching point connected in series with the latter, as a result of which the vacuum interrupter is relieved with the switch-disconnector switched through. To disconnect the switch-disconnector, the first step is to open the main contact in the known way, resulting in the voltage being conducted completely across the vacuum interrupter chamber 2. Subsequently, the contacts 21 and 22 of the vacuum interrupter chamber 2 are separated and the connection is completely interrupted without an arc flashover being able to form in the load interrupter switch 1.
The invention permits further approaches to configuration in addition to the exemplary embodiment set forth here.
The dimensions and configuration of the sleeve 4 can vary, depending on the design and type of construction of the vacuum interrupter chamber 2. It is essential in each case in this regard that the sleeve 4 bears against the vacuum interrupter chamber 2 in such a way that no air gap is possible therebetween.
The sleeve 4 need not be constructed with shields 41, but can also have an outer circumferential surface which is of a different configuration or smooth if it allows the safety of the load interrupter switch 1, for example on the basis of low prevailing voltages.
In the example shown, the cut-outs 42 in the sleeve 4 have semicircular cross sections and are constructed at four points around the vacuum interrupter chamber 2. Both the configuration and number of the annular cut-outs 42 can deviate from this. Furthermore, it is also possible to provide the cut-outs 42 with an annular configuration, instead of the embodiment shown, at points on the inner circumferential surface of the sleeve 4.
The pocket 43 in the sleeve 4 can also be provided on both end faces. Moreover, the configuration and the number of pockets 43 can vary in a way similar to that in the case of the cut-outs 42.
The sleeve 4 can be used in an arbitrary way in conjunction with vacuum interrupter chambers 2, something which also includes switching elements other than switch-disconnectors. Thus, use i~ circuit-breakers and the like is also conceivable.
The pressure housing can also comprise more than two part housings, the number of the sealing beads 44 being matched to the number of the mounting joints.
Furthermore, it is also possible to provide in parallel with the vacuum interrupter chamber 2 a continuous current or primary current contact system which permits the load interrupter switch 1 to be designed for various nominal or continuous currents in conjunction with the use of a specific vacuum interrupter chamber 2.
The invention thus creates a load interrupter switch 1 for voltages in the kV range and having a vacuum interrupter chamber 2 which is embraced without a gap by a sleeve 4 constructed from elastomeric material of high dielectric strength. The sleeve 4 is, for its part, clamped by the half housings 11 and 12 of the load interrupter switch 1. In this way, an external flashover of the high voltage between the end plates 24 and 25 of the vacuum interrupter chamber 2 is effectively suppressed during the switching operation without the need for liquid or gaseous media for this purpose. As a result, by contrast with conventional load interrupter switches there is no need for a high outlay on monitoring, and the load interrupter switch is unobjectionable with regard to the environment.
Claims (12)
1. Load interrupter switch (1) for voltages above 1 kV, having a vacuum interrupter chamber (2) whose contacts (21, 22) are closed or opened by means of a switching mechanism (3), the vacuum interrupter chamber (2) having a housing (23) with metallic end plates (24, 25) which encloses the switching contacts situated in the vacuum, and a cylindrical housing middle part (26) made from an electrically insulating material, which housing is surrounded by a coating which is made from a dielectric material and grips the edges of the two end plates (24, 25) behind, it being the case that provided on the outside of the dielectric coating is a jacket of complementary construction, which is made from insulating material and pressurizes the outer circumference of the dielectric coating, characterized in that the dielectric coating is formed by a prefabricated sleeve (4) which consists of an elastomeric material of high dielectric strength which is pressed against the housing (23) without a gap by a pressure housing (11, 12) serving as the jacket.
2. Load interrupter switch according to Claim 1, characterized in that the dimensions of the sleeve (4) are selected such that the sleeve (4) bears in a pretensioned fashion against the circumference of the vacuum interrupter chamber (2).
3. Load interrupter switch according to Claim 2, characterized in that the sleeve (4) has at least one sealing bead (44) which runs in the axial direction of the pressure housing (11, 12) and comes to lie in the mounting joint of the pressure housing (11, 12).
4. Load interrupter switch according to Claim 3, characterized in that the sealing bead (44) has a thickened part (45) which can be pinched in the mounting joint of the pressure housing (11, 12).
5. Load interrupter switch according to one of Claims 1 to 4, characterized in that circumferential shields (41) are provided which project on the outer circumference of the sleeve (4) in a fashion essentially parallel to the end plates (24, 25) of the vacuum interrupter chamber (2).
6. Load interrupter switch according to one of Claims 1 to 5, characterized in that the sleeve (4) has at least one cut-out (42) for holding material displaced during the pressure loading by the pressure housing-(11, 12).
7. Load interrupter switch according to Claim 6, characterized in that the at least one cut-out (42) is constructed as a circumferential annular groove.
8. Load interrupter switch according to one of Claims 1 to 7, characterized in that at least one pocket (43) is constructed on the sleeve (4) in the region of the end plate (25) and/or the end plate (24).
9. Load interrupter switch according to Claim 8, characterized in that the at least one pocket (43) is constructed as an annular groove.
10. Load interrupter switch according to one of Claims 1 to 9, characterized in that the sleeve (4) is constructed from silicone rubber or from EPDM
(Ethylene-Propylene-Terpolymer).
(Ethylene-Propylene-Terpolymer).
11. Load interrupter switch according to one of Claims 1 to 10, characterized in that it is constructed as a switch-disconnector in the case of which a visible isolating distance is arranged in series with the vacuum interrupter chamber.
12. Load interrupter switch according to one of Claims 1 to 11, characterized in that in the closed state of the load interrupter switch a circuit for high continuous current-carrying capacity is connected in parallel with he vacuum interrupter chamber or in parallel with the series circuit of the vacuum interrupter chamber/visible isolating distance.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19634451A DE19634451C1 (en) | 1996-08-26 | 1996-08-26 | Load switch |
| DE19634451.4 | 1996-08-26 | ||
| PCT/EP1997/004617 WO1998009310A1 (en) | 1996-08-26 | 1997-08-25 | Load interrupter switch |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2263881A1 CA2263881A1 (en) | 1998-03-05 |
| CA2263881C true CA2263881C (en) | 2006-11-28 |
Family
ID=7803719
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002263881A Expired - Lifetime CA2263881C (en) | 1996-08-26 | 1997-08-25 | A hermetically sealed vacuum load interrupter switch with flashover protection features |
Country Status (18)
| Country | Link |
|---|---|
| EP (1) | EP0920705B2 (en) |
| AT (1) | ATE191990T1 (en) |
| AU (1) | AU4618397A (en) |
| CA (1) | CA2263881C (en) |
| CZ (1) | CZ288889B6 (en) |
| DE (2) | DE19634451C1 (en) |
| DK (1) | DK0920705T4 (en) |
| ES (1) | ES2144880T5 (en) |
| GR (1) | GR3033287T3 (en) |
| HK (1) | HK1017768A1 (en) |
| HU (1) | HU222705B1 (en) |
| PL (1) | PL187251B1 (en) |
| PT (1) | PT920705E (en) |
| RS (1) | RS49698B (en) |
| RU (1) | RU2188474C2 (en) |
| SK (1) | SK282723B6 (en) |
| TR (1) | TR199900436T2 (en) |
| WO (1) | WO1998009310A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6130394A (en) * | 1996-08-26 | 2000-10-10 | Elektrotechnische Weke Fritz Driescher & Sohne GmbH | Hermetically sealed vacuum load interrupter switch with flashover features |
| DE19712182A1 (en) * | 1997-03-22 | 1998-09-24 | Abb Patent Gmbh | Vacuum chamber |
| DE19906972B4 (en) * | 1999-02-19 | 2008-04-30 | Abb Ag | Switch pole with vacuum switching chamber |
| DE19918077C1 (en) * | 1999-04-21 | 2000-11-09 | Driescher Eltech Werk | HV load switch e.g. for electric railway, has vacuum switch chamber adjacent main switching contacts containing contacts which are closed for extinguishing arc between main switching contacts |
| FR2794280B1 (en) * | 1999-05-28 | 2001-07-20 | Alstom | MEDIUM-VOLTAGE CIRCUIT BREAKER WITH VACUUM CUTTING PROVIDED WITH A POLE PROTECTION CASE |
| DE102004006476B4 (en) * | 2004-02-04 | 2006-02-09 | Siemens Ag | Switch disconnectors |
| FR3073663A1 (en) * | 2017-11-16 | 2019-05-17 | Schneider Electric Industries Sas | CUT POLE FOR ELECTRICAL CUTTING APPARATUS |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1191664A (en) * | 1966-06-07 | 1970-05-13 | Reyrolle & Company Ltd | Improvements relating to Vacuum Switches |
| US3594525A (en) * | 1969-04-21 | 1971-07-20 | Gen Electric | Common parallel operating means for series-connected, laterally offset vacuum switches |
| US3671696A (en) * | 1970-11-16 | 1972-06-20 | Allis Chalmers Mfg Co | Vacuum interrupter shunted with mechanical switch |
| DE2322372C3 (en) † | 1973-04-30 | 1980-06-04 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Multipole vacuum switching device with switching vessels encapsulated in insulating material |
| US4088859A (en) * | 1977-02-23 | 1978-05-09 | Westinghouse Electric Corp. | Normal open low voltage vacuum shorting switch |
| US4393286A (en) * | 1978-08-24 | 1983-07-12 | Tokyo Shibaura Denki Kabushiki Kaisha | Vacuum circuit breakers |
| JPS5812230A (en) * | 1981-07-16 | 1983-01-24 | 富士電機株式会社 | Vacuum laod switch with disconnecting switch |
| FR2698481B1 (en) * | 1992-11-26 | 1995-02-17 | Soule Sa | Electrical line cut-off system comprising a switch under controlled atmosphere. |
| DE9314754U1 (en) * | 1993-09-27 | 1994-03-03 | Siemens AG, 80333 München | Vacuum interrupter with an encapsulation resistant to internal pressure |
-
1996
- 1996-08-26 DE DE19634451A patent/DE19634451C1/en not_active Expired - Lifetime
-
1997
- 1997-08-25 SK SK238-99A patent/SK282723B6/en not_active IP Right Cessation
- 1997-08-25 TR TR1999/00436T patent/TR199900436T2/en unknown
- 1997-08-25 HU HU9903117A patent/HU222705B1/en active IP Right Grant
- 1997-08-25 PL PL97331997A patent/PL187251B1/en unknown
- 1997-08-25 RS YUP-102/99A patent/RS49698B/en unknown
- 1997-08-25 CZ CZ1999585A patent/CZ288889B6/en not_active IP Right Cessation
- 1997-08-25 CA CA002263881A patent/CA2263881C/en not_active Expired - Lifetime
- 1997-08-25 PT PT97944787T patent/PT920705E/en unknown
- 1997-08-25 AT AT97944787T patent/ATE191990T1/en active
- 1997-08-25 AU AU46183/97A patent/AU4618397A/en not_active Abandoned
- 1997-08-25 DE DE59701481T patent/DE59701481D1/en not_active Expired - Lifetime
- 1997-08-25 WO PCT/EP1997/004617 patent/WO1998009310A1/en active IP Right Grant
- 1997-08-25 DK DK97944787T patent/DK0920705T4/en active
- 1997-08-25 ES ES97944787T patent/ES2144880T5/en not_active Expired - Lifetime
- 1997-08-25 EP EP97944787A patent/EP0920705B2/en not_active Expired - Lifetime
- 1997-08-25 RU RU99105735/09A patent/RU2188474C2/en active
-
1999
- 1999-06-30 HK HK99102763A patent/HK1017768A1/en not_active IP Right Cessation
-
2000
- 2000-04-20 GR GR20000400964T patent/GR3033287T3/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CZ58599A3 (en) | 1999-07-14 |
| SK23899A3 (en) | 2000-03-13 |
| HK1017768A1 (en) | 1999-11-26 |
| RS49698B (en) | 2007-12-31 |
| ES2144880T3 (en) | 2000-06-16 |
| EP0920705B1 (en) | 2000-04-19 |
| SK282723B6 (en) | 2002-11-06 |
| DE19634451C1 (en) | 1998-01-29 |
| TR199900436T2 (en) | 1999-05-21 |
| ATE191990T1 (en) | 2000-05-15 |
| HU222705B1 (en) | 2003-09-29 |
| YU10299A (en) | 1999-11-22 |
| DE59701481D1 (en) | 2000-05-25 |
| ES2144880T5 (en) | 2004-02-16 |
| DK0920705T4 (en) | 2003-06-30 |
| PT920705E (en) | 2000-10-31 |
| PL187251B1 (en) | 2004-06-30 |
| HUP9903117A2 (en) | 2000-02-28 |
| RU2188474C2 (en) | 2002-08-27 |
| WO1998009310A1 (en) | 1998-03-05 |
| PL331997A1 (en) | 1999-08-16 |
| GR3033287T3 (en) | 2000-09-29 |
| EP0920705B2 (en) | 2003-05-14 |
| DK0920705T3 (en) | 2000-09-25 |
| AU4618397A (en) | 1998-03-19 |
| HUP9903117A3 (en) | 2002-03-28 |
| EP0920705A1 (en) | 1999-06-09 |
| CZ288889B6 (en) | 2001-09-12 |
| CA2263881A1 (en) | 1998-03-05 |
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| Date | Code | Title | Description |
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| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20170825 |