CA2121642C - Gas-discharge overvoltage arrester - Google Patents
Gas-discharge overvoltage arresterInfo
- Publication number
- CA2121642C CA2121642C CA002121642A CA2121642A CA2121642C CA 2121642 C CA2121642 C CA 2121642C CA 002121642 A CA002121642 A CA 002121642A CA 2121642 A CA2121642 A CA 2121642A CA 2121642 C CA2121642 C CA 2121642C
- Authority
- CA
- Canada
- Prior art keywords
- electrode
- cap
- cylindrical part
- overvoltage arrester
- gas discharge
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
- H01T1/00—Details of spark gaps
- H01T1/14—Means structurally associated with spark gap for protecting it against overload or for disconnecting it in case of failure
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
- H01C7/12—Overvoltage protection resistors
Abstract
A gas-filled three-electrode overvoltage arrester may be developed in such a manner that it has dependable "fall-safe" and "vent-safe" behavior. For this purpose, a two-arm spring clip (10) is fastened to the center electrode (1). The ends of the two-arm spring clip (10) rest, with the interpositioning of a spacer (20, 21; 22, 23), against the ends of the end electrodes (2, 3). The end of each arm of the spring clip bears a cap (14, 15) which is provided with a flange-like edge (16, 17). One end of the connecting wire (6, 7) of each end electrode has the shape of a ring (61, 71) which is fastened at the end side to the end electrode. The ring of the connecting wire and the flange-like edge of the cap are opposite each other and are held apart by a disk-shaped fusible pellet (20, 22) and a cylindrical part (21, 23) having insulating properties. The cylindrical part consists either of a temperature-resistant insulating material or of a metal-oxide varistor.
Description
GA8-DIe~U~P~ Ov~K~OLTAG~ ARR~8TER
BACKGROUND OF THE INVENTION
; The present invention relates to the field of electric components and is intended to be used in the construction of gas-discharge overvoltage arresters which, in addition to a center electrode, have two end electrodes and are developed by means of an accessory device so that they have a so-called fail-safe behavior and possibly al~o a so-called vent-safe behavior.
One known overvoltage arrester of this type includes an annular center electrode, two hollow-cylindrical insulating bodies arranged laterally thereof, and two end electrodes arranged at the ends of the insulating members.
A two-arm spring clip is attached to the center electrode, the ends of the two arms resting against the circumference of the two electrodes with the interpositioning of an insulating spacer. A coating of a polyurethane resin is employed as a spacer. This resin coating can melt upon overheating of the arrester, as a result of which the end of the arm of the spring clip comes into contact witX the end electrode and thus short-circuits the overvoltage arrester. This property of the overvoltage arrester is ~1216~2 referred to as "fail-safe behavior". Furthermore, the ends of the arms of the spring clip are developed with a sharp edge so that a high electric field strength may be developed on these sharp edges. This is of importance when the overvoltage arrester has failed due to a lack of tightness in the housing. In that case, overvoltages which occur can be discharged subsidiarily via the air discharge gap formed between the sharp end of the arm of the spring clip and the end electrodes. This property of the overvoltage arrester is referred to as "vent-safe behavior~ (see U.S. Patent No. 4,912,592).
In order to produce fail-safe behavior in the case of a three-electrode overvoltage arrester, a construction is also known in which the ends of the arms of the spring clip rest axially rather than radially against the end electrodes, with the interposition of a fusible plastic member. Upon overheating of the arrester, the substantially cylindrical plastic member melts, as a result of which the spring clip comes against the end electrode and thus short-circuits the overvoltage arrester (see U.S. Patent No. 4,984,125, Fig. la). In this known embodiment of an overvoltage arrester, both the center electrode and the end electrode are provided with radially extended connecting wires.
For overvoltage arresters having only two electrodes, it is furthermore known to obtain fail-safe behavior by the use of a disk of solder material of low melting point, a contact device which is under axial spring force being 21216~2 clamped against the disk of solder material and being displaced axially upon the melting of the solder disk, thereby short-circuiting the overvoltage arrester. In order to assure the vent-safe behavior, a back-up in the form of an air discharge gap is provided on the one electrode in the case of this known overvoltage arrester (see U.S. Patent No. 4,366,412).
In the aforementioned three-electrode overvoltage arresters including a spring clip fastened to the center electrode, only a point contact between the spring clip and the end electrodes is formed in the event of thermal overloading of the arrester. In the event of very high short-circuit currents, there is therefore the danger that the ends of the arms of the spring clip will be thermally destroyed.
SU~IARY OF THE INVENTION
The present invention relates to a gas-~icch~rge overvoltage arrester developed such that the spring clip is fastened to the center electrode to establish a dependable contacting which can also carry high currents in the event of an overload. This development makes it possible at the same time to impart "vent-safe properties"
to the overvoltage arrester.
In accordance with the present invention, the connecting wire of each end electrode has, on the arrester end, the shape of a ring which is fastened on the end of the end electrode. Furthermore, the end of each arm of the sprlng clip bears a cap provlded wlth a flange-llke edge, the diameter of which corresponds to the diameter of the annular connection. The spacer between each end electrode and the cap consist of a disk-shaped fusible pellet and a temperature-reslstant cyllndrlcal part havlng lnsulating properties. Additionally, the outside diameter of the fusible pellet and that of the cylindrical part are smaller than the inside dlameter of the cap.
With a gas dlscharge overvoltage arrester developed in this manner, a relatively large contact surface ls avail-able in the event of a short clrcult. This surface ls formed, on the one hand, by the flange-like edge of the cap on the spring cllp and, on the other hand, by the rlng-shaped part of the connectlon of the end electrode. If the overvoltage arrester is merely to have a fail-safe behaviour, it is preferable to arrange the dlsk-shaped fusible pellet between the end electrode and the cyllndrical part and to use a temperature-resistant insulating material such as plexiglass or ceramlc, for instance, for the temperature-resistant cylin-drlcal part. The radial attachment of these two parts lseffected in this connection, on the one hand, by the wall of the cap and, on the other hand, by the inner wall of the annular electrode connection.
If the overvoltage arrester is also to exhlbit vent-safe behaviour, a metal-oxlde varlstor may be used as the cylindrical part, the response voltage of which is greater than the response voltage of the overvoltage arrester. The r~
' ~b.
ends of the metal-oxlde varlstor are preferably metalllzed and the rest of the surface is preferably sealed with a moisture-repelling substance. Dependlng on the shape of the cap, an insulating intermediate layer can, furthermore, be arranged on the outer surface of the metal-oxide varistor The use of such a cylindrical part provides assurance that the vent-safe behaviour is independent of the humidlty of the alr, without having to provide for this purpose a special encapsulation of the vent-safe assembly, which is expensive to manufacture.
Metal-oxide varistors are readily available commercial components, for example as described in U.S. Patent No.
3,905,006 and U.S. Patent No. 4,317,101.
In accordance with the present invention, there l.s provided a gas discharge overvoltage arrester comprislng: two hollow-cyllndrlcal lnsulatlng members; a rlng-shaped center electrode arranged between said two hollow-cyllndrical lnsulating members; two end electrodes respectlvely arranged at ends of the two hollow-cylindrlcal lnsulating members; a two-arm spring cllp fastened on the center electrode ln connectlon with which the ends of the arms rest agalnst the ends of the end electrodes with the interposition of a spacer between the end of each arm and each electrode; wherein the center electrode and the end electrodes are provided wlth radially extended connections, the connection of each end electrode at the arrester end has a shape of a rlng whlch ls fastened to the end of the end electrode, the end of each arm of the sprlng cllp bearlng a cap, the cap belng provlded with ~';.
a flange-llke edge the dlameter of whlch corresponds to the diameter of the ring shaped connection; and whereln the spacer between each end electrode and the cap comprises a dlsk-shaped fusible pellet and a cyllndrical part having insulating propertles, an outside dlameter of the fuslble pellet and an outside dlameter of the cylindrical part belng smaller than an lnslde diameter of the cap.
BRIEF DESCRIPTION OF THE DRAWINGS
Three embodiments of a gas-discharge overvoltage arrester according to the present lnvention are shown ln Figs.
1 to 3.
Fig. 1 illustrates a side vlew of a gas discharge overvoltage arrestor accordlng to an embodiment of the present invention.
Fig. 2 illustrates an end view of a gas discharge overvoltage arrestor according to an embodiment of the present invention.
Fig. 3 illustrates a side view of a portion of a gas dlscharge overvoltage arrestor according to an embodiment of the present invention.
DETAILED DESCRIPTION
In accordance wlth the side vlew lllustrated in Flg.
1 and the end view illustrated in Fig. 2, the overvoltage arrester consists of an annular center electrode 1, two end electrodes 2 and 3, and lnsulatlng hollow cylinders 4 and 5 arranged therebetween. The center electrode 1 is provided with a radially extended connecting wlre 8 and the end electrodes 2 -2l2l642 6a and 3 are simllarly provided wlth radlally extended connectlng wires 6 and 7. However, at the end located on the electrode slde, they are formed lnto an open rlng 61 and 71, respect-ively. This ring is attached firmly to the end of the corresponding end electrode by solderlng or weldlng Instead of a wire which is shaped into a ring at one end, a corres-ponding stamplng can also be used. Alternatlvely ring and connecting wire may be different parts welded to~ether.
A two-arm sprlng clip 10 is fastened on the over-voltage arrester. For thls purpose, a centrally arranged clamp 11 ls seated ln form-locked manner on the center electrode 1.
The ends of the two arms 12 and 13 lle in an axial directlon of the overvoltage arrester at the end agalnst the end electrodes 2 and 3 wlth a speclal development being provided.
That is, on the ends of the arms 12 and 13, hollow cylindrical or slightly conlcally opened caps 14 and 15 are arranged, respectively, which are provided wlth flange-like edges 16 and 17, respectively. The center diameter of this flange-like edge corresponds to the center diameter of the ring 61 or 71 into which the one end of the connecting wires 6 and 7 respectively is bent.
Between the flange-like edge 16 or 17 and the wire rings 61 or 71 there is a distance of about 0.2 to 0.3 mm, 5 this distance being determined by a fusible pellet 20 or 22 with the shape of an annular disk and a cylindrical part 21 or 23. Cylindrical part 21 is a cylindrical body of temperature-resistant insulating material, for instance f of a glass having a base of plastic or of ceramic. The 10 part 21 can in itself also be of a hollow-cylindrical or block shape. The thermal resistance or resistance to heat and insulating property of part 21 are important in order that in the event of an overload of the arrester, only the fusible pellet 20 will melt in a well-defined manner and 15 the flange-like edge 16 will be pressed thereby against the connecting ring 61.
Normally, the overvoltage arrester is provided at both end electrodes 2 and 3 with a fusible pellet 20 and an insulating spacer 21. However, if the arrester is not 20 also to have a "vent-safe behavior", the overvoltage arrester at both end electrodes is equipped in the manner shown for the end electrode 3. In this case, a cylindrical metal-oxide varistor is provided as a spacer 23, its response voltage being greater than the response 25 voltage of the overvoltage arrester. As a response voltage of such a varistor, there applies in all cases that voltage at which the varistor conducts a current of 1 mA. The dimensioning of the varistor, i.e., in particular, the diameter, the height and the selection of the material can be effected by the expert so that the response voltage of the varistor is, for instance, 5 to 10% or else between 10 and 40% above the response voltage of the overvoltage arrester. For dependable operation of the metal-oxide varistor, it is necessary in this connection that its ends be provided with a metallization 26 and that the rest of the surface be sealed with a ! moisture-repelling substance, for instance by impregnating with a hardenable silicone oil or by immersion in a silicone resin. In the event of the use of a hollow cylindrical cap it is advisable to apply an insulating intermediate layer on the outer surface in order to prevent contact between the outer surface and the cap 15 or the connecting ring 71. Such an insulating intermediate layer can consist of a layer of glass, a layer of plastic in the form of a shrinkdown tubing, or else a rubber ring. In Fig. 1 a rubber ring 24, which, of course, encloses only a part of the outer surface of the metal-oxide varistor 23, is shown as an insulating intermediate layer. When a cap which is slightly conically open is used, the insulating intermediate layer can be dispensed with, since the varistor then rests against the wall of the cap only with its one end edge in the region of the smallest inside diameter of the cap.
The side view of Fig. 2 shows, in particular, the ring-shaped development of the connecting wire 6 to form 212~2 an open ring 61, as well as the development of the clamp 11 .
In Fig. 1, the fusible pellet 22 is arranged between the metal-oxide varistor 23 and the cylindrical cap 15.
S As an alternative, the fusible pellet 22 can also be arranged between the varistor 23 and the end electrode 3, as illustrated in Fig. 3. Fig. 3 also illustrates a layer of glass 25 on the outer surface of the varistor 23, by means of which, on the one hand, the outer surface of the varistor 23 is insulated from the cylindrical part of the cap 15 and from the wire ring 17 and, on the other hand, the varistor is sealed in a moisture-tight manner.
BACKGROUND OF THE INVENTION
; The present invention relates to the field of electric components and is intended to be used in the construction of gas-discharge overvoltage arresters which, in addition to a center electrode, have two end electrodes and are developed by means of an accessory device so that they have a so-called fail-safe behavior and possibly al~o a so-called vent-safe behavior.
One known overvoltage arrester of this type includes an annular center electrode, two hollow-cylindrical insulating bodies arranged laterally thereof, and two end electrodes arranged at the ends of the insulating members.
A two-arm spring clip is attached to the center electrode, the ends of the two arms resting against the circumference of the two electrodes with the interpositioning of an insulating spacer. A coating of a polyurethane resin is employed as a spacer. This resin coating can melt upon overheating of the arrester, as a result of which the end of the arm of the spring clip comes into contact witX the end electrode and thus short-circuits the overvoltage arrester. This property of the overvoltage arrester is ~1216~2 referred to as "fail-safe behavior". Furthermore, the ends of the arms of the spring clip are developed with a sharp edge so that a high electric field strength may be developed on these sharp edges. This is of importance when the overvoltage arrester has failed due to a lack of tightness in the housing. In that case, overvoltages which occur can be discharged subsidiarily via the air discharge gap formed between the sharp end of the arm of the spring clip and the end electrodes. This property of the overvoltage arrester is referred to as "vent-safe behavior~ (see U.S. Patent No. 4,912,592).
In order to produce fail-safe behavior in the case of a three-electrode overvoltage arrester, a construction is also known in which the ends of the arms of the spring clip rest axially rather than radially against the end electrodes, with the interposition of a fusible plastic member. Upon overheating of the arrester, the substantially cylindrical plastic member melts, as a result of which the spring clip comes against the end electrode and thus short-circuits the overvoltage arrester (see U.S. Patent No. 4,984,125, Fig. la). In this known embodiment of an overvoltage arrester, both the center electrode and the end electrode are provided with radially extended connecting wires.
For overvoltage arresters having only two electrodes, it is furthermore known to obtain fail-safe behavior by the use of a disk of solder material of low melting point, a contact device which is under axial spring force being 21216~2 clamped against the disk of solder material and being displaced axially upon the melting of the solder disk, thereby short-circuiting the overvoltage arrester. In order to assure the vent-safe behavior, a back-up in the form of an air discharge gap is provided on the one electrode in the case of this known overvoltage arrester (see U.S. Patent No. 4,366,412).
In the aforementioned three-electrode overvoltage arresters including a spring clip fastened to the center electrode, only a point contact between the spring clip and the end electrodes is formed in the event of thermal overloading of the arrester. In the event of very high short-circuit currents, there is therefore the danger that the ends of the arms of the spring clip will be thermally destroyed.
SU~IARY OF THE INVENTION
The present invention relates to a gas-~icch~rge overvoltage arrester developed such that the spring clip is fastened to the center electrode to establish a dependable contacting which can also carry high currents in the event of an overload. This development makes it possible at the same time to impart "vent-safe properties"
to the overvoltage arrester.
In accordance with the present invention, the connecting wire of each end electrode has, on the arrester end, the shape of a ring which is fastened on the end of the end electrode. Furthermore, the end of each arm of the sprlng clip bears a cap provlded wlth a flange-llke edge, the diameter of which corresponds to the diameter of the annular connection. The spacer between each end electrode and the cap consist of a disk-shaped fusible pellet and a temperature-reslstant cyllndrlcal part havlng lnsulating properties. Additionally, the outside diameter of the fusible pellet and that of the cylindrical part are smaller than the inside dlameter of the cap.
With a gas dlscharge overvoltage arrester developed in this manner, a relatively large contact surface ls avail-able in the event of a short clrcult. This surface ls formed, on the one hand, by the flange-like edge of the cap on the spring cllp and, on the other hand, by the rlng-shaped part of the connectlon of the end electrode. If the overvoltage arrester is merely to have a fail-safe behaviour, it is preferable to arrange the dlsk-shaped fusible pellet between the end electrode and the cyllndrical part and to use a temperature-resistant insulating material such as plexiglass or ceramlc, for instance, for the temperature-resistant cylin-drlcal part. The radial attachment of these two parts lseffected in this connection, on the one hand, by the wall of the cap and, on the other hand, by the inner wall of the annular electrode connection.
If the overvoltage arrester is also to exhlbit vent-safe behaviour, a metal-oxlde varlstor may be used as the cylindrical part, the response voltage of which is greater than the response voltage of the overvoltage arrester. The r~
' ~b.
ends of the metal-oxlde varlstor are preferably metalllzed and the rest of the surface is preferably sealed with a moisture-repelling substance. Dependlng on the shape of the cap, an insulating intermediate layer can, furthermore, be arranged on the outer surface of the metal-oxide varistor The use of such a cylindrical part provides assurance that the vent-safe behaviour is independent of the humidlty of the alr, without having to provide for this purpose a special encapsulation of the vent-safe assembly, which is expensive to manufacture.
Metal-oxide varistors are readily available commercial components, for example as described in U.S. Patent No.
3,905,006 and U.S. Patent No. 4,317,101.
In accordance with the present invention, there l.s provided a gas discharge overvoltage arrester comprislng: two hollow-cyllndrlcal lnsulatlng members; a rlng-shaped center electrode arranged between said two hollow-cyllndrical lnsulating members; two end electrodes respectlvely arranged at ends of the two hollow-cylindrlcal lnsulating members; a two-arm spring cllp fastened on the center electrode ln connectlon with which the ends of the arms rest agalnst the ends of the end electrodes with the interposition of a spacer between the end of each arm and each electrode; wherein the center electrode and the end electrodes are provided wlth radially extended connections, the connection of each end electrode at the arrester end has a shape of a rlng whlch ls fastened to the end of the end electrode, the end of each arm of the sprlng cllp bearlng a cap, the cap belng provlded with ~';.
a flange-llke edge the dlameter of whlch corresponds to the diameter of the ring shaped connection; and whereln the spacer between each end electrode and the cap comprises a dlsk-shaped fusible pellet and a cyllndrical part having insulating propertles, an outside dlameter of the fuslble pellet and an outside dlameter of the cylindrical part belng smaller than an lnslde diameter of the cap.
BRIEF DESCRIPTION OF THE DRAWINGS
Three embodiments of a gas-discharge overvoltage arrester according to the present lnvention are shown ln Figs.
1 to 3.
Fig. 1 illustrates a side vlew of a gas discharge overvoltage arrestor accordlng to an embodiment of the present invention.
Fig. 2 illustrates an end view of a gas discharge overvoltage arrestor according to an embodiment of the present invention.
Fig. 3 illustrates a side view of a portion of a gas dlscharge overvoltage arrestor according to an embodiment of the present invention.
DETAILED DESCRIPTION
In accordance wlth the side vlew lllustrated in Flg.
1 and the end view illustrated in Fig. 2, the overvoltage arrester consists of an annular center electrode 1, two end electrodes 2 and 3, and lnsulatlng hollow cylinders 4 and 5 arranged therebetween. The center electrode 1 is provided with a radially extended connecting wlre 8 and the end electrodes 2 -2l2l642 6a and 3 are simllarly provided wlth radlally extended connectlng wires 6 and 7. However, at the end located on the electrode slde, they are formed lnto an open rlng 61 and 71, respect-ively. This ring is attached firmly to the end of the corresponding end electrode by solderlng or weldlng Instead of a wire which is shaped into a ring at one end, a corres-ponding stamplng can also be used. Alternatlvely ring and connecting wire may be different parts welded to~ether.
A two-arm sprlng clip 10 is fastened on the over-voltage arrester. For thls purpose, a centrally arranged clamp 11 ls seated ln form-locked manner on the center electrode 1.
The ends of the two arms 12 and 13 lle in an axial directlon of the overvoltage arrester at the end agalnst the end electrodes 2 and 3 wlth a speclal development being provided.
That is, on the ends of the arms 12 and 13, hollow cylindrical or slightly conlcally opened caps 14 and 15 are arranged, respectively, which are provided wlth flange-like edges 16 and 17, respectively. The center diameter of this flange-like edge corresponds to the center diameter of the ring 61 or 71 into which the one end of the connecting wires 6 and 7 respectively is bent.
Between the flange-like edge 16 or 17 and the wire rings 61 or 71 there is a distance of about 0.2 to 0.3 mm, 5 this distance being determined by a fusible pellet 20 or 22 with the shape of an annular disk and a cylindrical part 21 or 23. Cylindrical part 21 is a cylindrical body of temperature-resistant insulating material, for instance f of a glass having a base of plastic or of ceramic. The 10 part 21 can in itself also be of a hollow-cylindrical or block shape. The thermal resistance or resistance to heat and insulating property of part 21 are important in order that in the event of an overload of the arrester, only the fusible pellet 20 will melt in a well-defined manner and 15 the flange-like edge 16 will be pressed thereby against the connecting ring 61.
Normally, the overvoltage arrester is provided at both end electrodes 2 and 3 with a fusible pellet 20 and an insulating spacer 21. However, if the arrester is not 20 also to have a "vent-safe behavior", the overvoltage arrester at both end electrodes is equipped in the manner shown for the end electrode 3. In this case, a cylindrical metal-oxide varistor is provided as a spacer 23, its response voltage being greater than the response 25 voltage of the overvoltage arrester. As a response voltage of such a varistor, there applies in all cases that voltage at which the varistor conducts a current of 1 mA. The dimensioning of the varistor, i.e., in particular, the diameter, the height and the selection of the material can be effected by the expert so that the response voltage of the varistor is, for instance, 5 to 10% or else between 10 and 40% above the response voltage of the overvoltage arrester. For dependable operation of the metal-oxide varistor, it is necessary in this connection that its ends be provided with a metallization 26 and that the rest of the surface be sealed with a ! moisture-repelling substance, for instance by impregnating with a hardenable silicone oil or by immersion in a silicone resin. In the event of the use of a hollow cylindrical cap it is advisable to apply an insulating intermediate layer on the outer surface in order to prevent contact between the outer surface and the cap 15 or the connecting ring 71. Such an insulating intermediate layer can consist of a layer of glass, a layer of plastic in the form of a shrinkdown tubing, or else a rubber ring. In Fig. 1 a rubber ring 24, which, of course, encloses only a part of the outer surface of the metal-oxide varistor 23, is shown as an insulating intermediate layer. When a cap which is slightly conically open is used, the insulating intermediate layer can be dispensed with, since the varistor then rests against the wall of the cap only with its one end edge in the region of the smallest inside diameter of the cap.
The side view of Fig. 2 shows, in particular, the ring-shaped development of the connecting wire 6 to form 212~2 an open ring 61, as well as the development of the clamp 11 .
In Fig. 1, the fusible pellet 22 is arranged between the metal-oxide varistor 23 and the cylindrical cap 15.
S As an alternative, the fusible pellet 22 can also be arranged between the varistor 23 and the end electrode 3, as illustrated in Fig. 3. Fig. 3 also illustrates a layer of glass 25 on the outer surface of the varistor 23, by means of which, on the one hand, the outer surface of the varistor 23 is insulated from the cylindrical part of the cap 15 and from the wire ring 17 and, on the other hand, the varistor is sealed in a moisture-tight manner.
Claims (6)
1. A gas discharge overvoltage arrester comprising:
two hollow-cylindrical insulating members;
a ring-shaped center electrode arranged between said two hollow-cylindrical insulating members;
two end electrodes respectively arranged at ends of the two hollow-cylindrical insulating members;
a two-arm spring clip fastened on the center electrode in connection with which the ends of the arms rest against the ends of the end electrodes with the interposition of a spacer between the end of each arm and each electrode;
wherein the center electrode and the end electrodes are provided with radially extended connections, the connection of each end electrode at the arrester end has a shape of a ring which is fastened to the end of the end electrode, the end of each arm of the spring clip bearing a cap, the cap being provided with a flange-like edge the diameter of which corresponds to the diameter of the ring shaped connection; and wherein the spacer between each end electrode and the cap comprises a disk-shaped fusible pellet and a cylindrical part having insulating properties, an outside diameter of the fusible pellet and an outside diameter of the cylindrical part being smaller than an inside diameter of the cap.
two hollow-cylindrical insulating members;
a ring-shaped center electrode arranged between said two hollow-cylindrical insulating members;
two end electrodes respectively arranged at ends of the two hollow-cylindrical insulating members;
a two-arm spring clip fastened on the center electrode in connection with which the ends of the arms rest against the ends of the end electrodes with the interposition of a spacer between the end of each arm and each electrode;
wherein the center electrode and the end electrodes are provided with radially extended connections, the connection of each end electrode at the arrester end has a shape of a ring which is fastened to the end of the end electrode, the end of each arm of the spring clip bearing a cap, the cap being provided with a flange-like edge the diameter of which corresponds to the diameter of the ring shaped connection; and wherein the spacer between each end electrode and the cap comprises a disk-shaped fusible pellet and a cylindrical part having insulating properties, an outside diameter of the fusible pellet and an outside diameter of the cylindrical part being smaller than an inside diameter of the cap.
2. A gas discharge overvoltage arrester according to claim 1, wherein the cylindrical part comprises a temperature-resistant insulating material and the fusible pellet is arranged between the end electrode and the cylindrical part.
3. A gas discharge overvoltage arrester according to claim 1, wherein the cylindrical part is formed of a metal-oxide varistor, a response voltage of which is greater than a response voltage of the overvoltage arrester, the ends of the metal-oxide varistor being metallized and the rest of the surface being sealed with a moisture-repelling substance.
4. A gas discharge overvoltage arrester according to claim 3, wherein an insulating intermediate layer is applied to the outer surface of the varistor.
5. A gas discharge overvoltage arrestor according to claim 1, wherein the cylindrical part comprises a temperature resistant insulating material.
6. A gas discharge overvoltage arrestor according to claim 5, wherein the temperature resistant insulating material comprises at least one of a group including plexiglass and ceramic.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4313651.6 | 1993-04-21 | ||
| DE4313651 | 1993-04-21 | ||
| DEP4318366.2 | 1993-05-28 | ||
| DE4318366A DE4318366A1 (en) | 1993-04-21 | 1993-05-28 | Gas-discharge overvoltage suppressor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2121642A1 CA2121642A1 (en) | 1994-10-22 |
| CA2121642C true CA2121642C (en) | 1998-08-18 |
Family
ID=25925275
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002121642A Expired - Fee Related CA2121642C (en) | 1993-04-21 | 1994-04-19 | Gas-discharge overvoltage arrester |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US5388023A (en) |
| CA (1) | CA2121642C (en) |
| DE (1) | DE9321371U1 (en) |
Families Citing this family (28)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4236538A1 (en) * | 1992-10-22 | 1994-04-28 | Siemens Ag | Encapsulated spark gap for overvoltage discharge - has two electrodes with collar-shaped edges forming dish shape, and glass insulator welded to collar edge |
| JP3495386B2 (en) * | 1993-06-03 | 2004-02-09 | 新光電気工業株式会社 | Arrester |
| DE4330178B4 (en) * | 1993-08-31 | 2005-01-20 | Epcos Ag | Gas-filled surge arrester with copper electrodes |
| US5508675A (en) * | 1994-03-18 | 1996-04-16 | Tii Industries Inc. | Miniature gas tube assembly with back-up air gap |
| ES2133124B1 (en) * | 1994-05-04 | 2000-04-01 | Cymem S A | IMPROVEMENTS INTRODUCED IN THE PATENT OF INVENTION P-9400938/4, BY: EXTERNAL SHORT CIRCUIT DEVICE FOR PROTECTION MODULES OF TELEPHONE AND SIMILAR EQUIPMENT. |
| DE4444515B4 (en) * | 1994-10-13 | 2009-10-01 | Epcos Ag | Gas-filled three-electrode surge arrester for high switching capacities |
| US5557065A (en) * | 1994-11-21 | 1996-09-17 | Siecor Corporation | Overvoltage protectors sealed with gel |
| DE19647748A1 (en) * | 1995-11-29 | 1997-06-05 | Siemens Ag | Gas-filled overvoltage diverter/arrester for lightning protection of communications networks |
| DE19647682C2 (en) * | 1995-11-30 | 1998-07-09 | Siemens Ag | Reserve spark gap for a gas-filled surge arrester and gas-filled three-electrode surge arrester with attached reserve spark gaps |
| US5880919A (en) * | 1997-06-24 | 1999-03-09 | Siecor Corporation | Gas tube surge protector with interacting varistors |
| US5999393A (en) * | 1997-06-24 | 1999-12-07 | Siecor Corporation | Surge protector and lead assembly with improved contact area between the protector and lead |
| DE19823446B4 (en) | 1998-05-18 | 2009-08-27 | Epcos Ag | Assembly for protecting telecommunications equipment against overvoltages |
| DE19928322A1 (en) | 1999-06-16 | 2000-12-21 | Siemens Ag | Gas-filled surge arrester with electrode connections in the form of band-like clamps |
| US6327129B1 (en) | 2000-01-14 | 2001-12-04 | Bourns, Inc. | Multi-stage surge protector with switch-grade fail-short mechanism |
| US6421218B1 (en) * | 2000-03-24 | 2002-07-16 | Corning Cable Systems Llc | Overvoltage protector |
| US7016171B2 (en) * | 2001-02-01 | 2006-03-21 | Hydro-Aire, Inc. | Current fault detector and circuit interrupter and packaging thereof |
| DE10134752B4 (en) * | 2001-07-17 | 2005-01-27 | Epcos Ag | Surge arresters |
| US6687109B2 (en) | 2001-11-08 | 2004-02-03 | Corning Cable Systems Llc | Central office surge protector with interacting varistors |
| DE10162916A1 (en) * | 2001-12-20 | 2003-07-10 | Epcos Ag | Spring clip, surge arrester with the spring clip and arrangement of a surge arrester |
| US6606232B1 (en) | 2002-03-28 | 2003-08-12 | Corning Cable Systems Llc | Failsafe surge protector having reduced part count |
| US7370658B2 (en) * | 2003-09-15 | 2008-05-13 | Placontrol, Inc. | Dental flosser with bendable head |
| DE102004025912A1 (en) * | 2004-05-27 | 2005-12-22 | Epcos Ag | Surge arresters |
| DE102005016848A1 (en) * | 2005-04-12 | 2006-10-19 | Epcos Ag | Surge arresters |
| US7974063B2 (en) * | 2007-11-16 | 2011-07-05 | Corning Cable Systems, Llc | Hybrid surge protector for a network interface device |
| DE102008022833A1 (en) | 2008-01-31 | 2009-08-06 | Epcos Ag | Electrical protection component with short-circuit device |
| DE102011052689B4 (en) * | 2011-08-12 | 2016-09-01 | Phoenix Contact Gmbh & Co. Kg | Gas-filled surge arrester with indirect monitoring of a short-circuit spring |
| CN105374653A (en) * | 2015-12-04 | 2016-03-02 | 深圳市槟城电子有限公司 | Gas discharge tube |
| US10741313B1 (en) * | 2019-02-06 | 2020-08-11 | Eaton Intelligent Power Limited | Bus bar assembly with integrated surge arrestor |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3905006A (en) * | 1972-12-29 | 1975-09-09 | Michio Matsuoka | Voltage dependent resistor |
| DE2951467C2 (en) * | 1979-12-20 | 1982-06-24 | Siemens AG, 1000 Berlin und 8000 München | Surge arrester with air spark gap connected in parallel |
| US4317101A (en) * | 1980-10-27 | 1982-02-23 | General Electric Company | Stable high voltage DC varistor |
| GB2205992B (en) * | 1987-05-01 | 1991-07-17 | Dubilier Plc | Gas-filled surge arrestor |
| JPH0227694U (en) * | 1988-08-10 | 1990-02-22 | ||
| US5027100A (en) * | 1990-02-12 | 1991-06-25 | Porta Systems Corp. | Gas tube fail safe device for telephone protector modules |
| JP3290209B2 (en) * | 1992-08-22 | 2002-06-10 | 新光電気工業株式会社 | Arrester |
| US5282109A (en) * | 1993-05-27 | 1994-01-25 | Tii Industries | Back-up air gaps |
-
1993
- 1993-05-28 DE DE9321371U patent/DE9321371U1/en not_active Expired - Lifetime
- 1993-09-28 US US08/128,422 patent/US5388023A/en not_active Expired - Lifetime
-
1994
- 1994-04-19 CA CA002121642A patent/CA2121642C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| DE9321371U1 (en) | 1997-09-04 |
| CA2121642A1 (en) | 1994-10-22 |
| US5388023A (en) | 1995-02-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |