EP3552282B1 - Overvoltage protection arrangement consisting of a horn spark gap accommodated in an insulating housing - Google Patents

Description

The invention is based on an overvoltage protection arrangement, consisting of a horn spark gap located in an insulating housing with a deion chamber for arc quenching, the deion chamber having a large number of spaced arcing plates and a trigger electrode located in the ignition area of the horn spark gap, furthermore with a varistor, which connects to the horn spark gap is electrically connected in series, according to the preamble of claim 1.

Horn spark gap lightning arresters with deion chambers for arc extinguishing are for example from the DE 10 2011 051 738 A1 previously known.

A corresponding horn spark gap is located in a housing and has means for controlling the internal gas flow in order to set a different behavior of the arc arising from a pulse current load on the one hand and the arc caused by the line follow current on the other.

In the case of such a horn spark gap, a trigger electrode can be arranged in the ignition area. This trigger electrode can comprise a conductive element which is surrounded by a sliding path. Adjacent sliding sections can also consist of an insulating or semiconducting material. The known trigger electrode is either used on one of the two electrodes in the ignition area or is preferably arranged between the two electrodes of the horn spark gap in the lower area of the ignition area. The DE 195 45 505 C1 shows a surge arrester with at least one voltage-dependent resistor, for example a varistor, and thermal shutdown devices.

These disconnection devices consist on the one hand of a fuse strip and on the other hand of a thermal release with a eutectic melt alloy.

When the fuse strip or the thermal fuse is opened, a damage indicator is activated with the aid of a spring force. A case of damage is thus visible.

In order to use simple means in a space-saving design to provide an indication of the fault that has occurred both in the event of an impermissible leakage current of the varistor caused by aging and in the event of an excessively high surge current producing a short circuit in the varistor, a housing is provided in which a surge-proof fuse strip is located. The damage indicator is a separate component which is detachably fastened to the housing and can be moved relative to the fuse housing after a spring has been released.

The thermal release is arranged outside the housing and is in a thermally conductive connection with the varistor in such a way that inadmissible heating of the varistor causes the thermal release to be disconnected and the damage is indicated.

From the DE 10 2014 215 282 B3 a combined surge protection device with an integrated spark gap is previously known. The spark gap has a series-connected fuse, the series circuit being connectable to a supply network with a first potential and a second potential different therefrom. The spark gap has two main electrodes. There is also a housing.

The fusible conductor connects a first connection to the second main electrode of the spark gap, the fuse also having a further contact, the further contact being arranged insulated from the first contact and insulated from the second main electrode of the spark gap. The overvoltage protection device has a plasma channel from leads the combustion chamber of the spark gap into the vicinity of the fusible conductor in such a way that plasma can have a targeted degrading effect on the fusible wire. As a result, the fuse wire can be destroyed.

In the case of the surge arrester with at least one varistor element and a disconnecting device according to DE 10 2011 011 254 A1 the disconnection device serves to disconnect the varistor discharge element from the network, the disconnection device being integrated into the electrical connection path of the discharge conductor arrangement.

The disconnection device comprises a device which switches a fuse into the electrical connection path in the event of a thermal overload of the varistor discharge element. The surge arrester arrangement is thus able to reduce the short-circuit current of the connected power supply or the connected network in the overload short-circuit state inside the varistor discharge element. Consequential damage to connected devices and / or internal connections can be reduced.

Based on the described prior art, it is the object of the invention to provide a further developed overvoltage protection arrangement, consisting of a horn spark gap located in an insulating housing with a deion chamber for arc quenching, which creates the possibility of all conceivable faults, i.e. if the thermal load is too high used varistors but also in the event of marginal arcs occurring within the deionization chamber to cause a shutdown, with each error state that has occurred, regardless of its cause or type, can be symbolized with a single display device and optionally reported remotely.

The object of the invention is achieved with the combination of features according to the teaching of patent claim 1, the subclaims including at least useful embodiments and developments.

Accordingly, an overvoltage protection arrangement consisting of a horn spark gap with a deion chamber for arc quenching located in an insulating housing is assumed. The deion chamber has a plurality of spaced-apart quenching plates, as shown for example in the DE 10 2011 051 738 A1 is shown.

A trigger electrode is located in the ignition area of the horn spark gap in order to make the response behavior of the spark gap adjustable. Furthermore, the overvoltage protection arrangement comprises a varistor, which is electrically connected in series with the horn spark gap.

According to the invention, a housing for accommodating the surge protection arrangement is designed, which accommodates a first and a second disconnection device.

The first disconnection device is in a thermally conductive connection with the varistor. When a limit temperature is reached or exceeded, a spring force-assisted slide is released, which interrupts the series connection between the varistor and the horn spark gap. This thermal separation device can for example comprise a soldering point which changes its physical state when the melting temperature is reached, so that the mentioned slide is able to execute the desired movement with the aid of the spring force support.

Furthermore, there is a second separating device which has a fusible conductor which is located in the area of the deionization chamber and can be exposed to an arc that occurs there. In one embodiment, the fusible conductor is in contact with extinguishing plates of the deionization chamber and melts when loaded, in particular when there is a line follow current load.

The fusible conductor is able to hold a spring force-assisted separating element in a first position, but also to release this separating element in the event of melting due to the effect of an arc, such that the separating element assumes a second position. When the second position has been reached, an electrical connection to the trigger electrode is interrupted. It is no longer possible to re-ignite the spark gap due to the overload that has occurred.

Furthermore, a three-pronged, rotatably mounted star or a circular disc with lugs is formed in the housing in such a way that a first star spike or lug with a star spike end is carried along by the slide when it is moved to interrupt the series connection.

In the same way, a second star point or nose with its star point end can be taken along when the separating element moves from the first to the second position, with the star or the disk being subject to a rotation about its axis of rotation as a result of the respective entrainment movement. The result is that a third star point or nose with its star point end releases a spring-force-supported, pivotable lever which actuates a remote signaling contact and / or an optical fault status indicator.

The respective action of either the slide or the separating element on the rotatably mounted star with the result of the then occurring rotation of the star and triggering of the pivotable lever corresponds to a quasi-mechanical "OR" link with regard to the separating devices.

According to the invention, by using the rotatably mounted star or the circular disk in a very confined space, the respective state of the respective separating device can be scanned, along with a mechanical movement, so that the aforementioned lever is released from its position fixed by the third star point.

In an embodiment of the invention, the trigger electrode is connected to one of the main electrodes of the horn spark gap via a voltage-limiting element. This aforementioned connection can be electrically interrupted by means of the isolating slide.

The housing has the horn spark gap and the varistor in a first housing level, with at least the separating element, the star and the lever as well as an actuation extension of the slide being formed in a second housing level.

As a result of the separating movement, the slide arrives in such a position that two metallic contacts are separated, the slide penetrating into the separating space and thereby preventing possible arcs.

When the second position is reached, the separating element lifts a spring contact clip from a contact surface of the voltage-switching element, so that the desired interruption of the electrical connection can thereby be achieved.

Both the slide and the separating element consist of an electrically insulating material.

The status display lever is pivotably mounted in the housing and has an angled portion at a first end of the lever which exposes or covers a display surface, with an actuating nose for the remote signaling contact being formed on a second end of the lever.

The display area can here preferably be a housing area or a window in the housing.

The axis of rotation of the star or the disk and the pivot axis of the lever are preferably parallel to one another and are spaced apart such that the third prong of the star can be moved from a stop position relative to the lever into a release position when the star is rotated.

At least the axis of rotation, the pivot axis, the star and the lever are components of a housing insert part which is located in the second housing plane. This housing insert forms a partition in relation to a housing level below, in which the horn spark gap and the varistor are located.

The overvoltage protection arrangement can be designed as a plug-in part with plug-in contacts for reception in a base part. The plug contacts are preferably located on an underside of the plug part. However, side surfaces of the plug-in part can have latching elements for fixing the plug-in part in the base part also have means for locking or unlocking these latching elements and for easier pulling of the plug-in part from the base part.

In a preferred embodiment of the invention, the fusible conductor of the second separation device is in contact with selected two spaced-apart quenching plates.

The voltage-limiting element is preferably designed as a gas discharge tube.

The invention will be explained in more detail below with the aid of an exemplary embodiment and with the aid of figures.

Fig. 1

eine Prinzipdarstellung einer Überspannungsschutzanordnung mit dargestellter erster und zweiter Abtrennvorrichtung nebst Drehstern und Hebelfunktionsanzeige in einem Zustand der vollständigen Funktion der eingesetzten Überspannungsableiter, insbesondere einer Hörnerfunkenstrecke und einem Varistor;

Fig. 2

eine Darstellung ähnlich derjenigen nach Fig. 1, jedoch im Zustand der ausgelösten ersten Abtrennvorrichtung mit Schieber und hierdurch resultierender Drehbewegung des Sterns nebst Freigabe des Hebels für die Federanzeige;

Fig. 3

eine Darstellung ähnlich derjenigen nach Fig. 2, jedoch hier mit ausgelöster zweiter Abtrennvorrichtung, wobei das Abtrennelement den Drehstern mitnimmt, so dass dieser wiederum den Hebel zur Zustandsanzeige freigeben kann; und

Fig. 4

eine perspektivische Darstellung einer Überspannungsschutzanordnung ausgebildet als Steckteil mit teilweise weggebrochenem Gehäuse und erkennbarem Gehäuseeinsatzteil (oberes Teil) nebst Drehstern, Hebel und dem Abtrennelement der zweiten Abtrennvorrichtung mit dem Detail eines Federkontaktbügels, der im ordnungsgemäßen Zustand mit einer Kontaktfläche eines Gasableiters in Verbindung steht.

Here show:

Fig. 1

a schematic diagram of an overvoltage protection arrangement with the illustrated first and second disconnecting device together with a rotating star and lever function display in a state of complete function of the surge arresters used, in particular a horn spark gap and a varistor;

Fig. 2

a representation similar to that after Fig. 1 , but in the state of the triggered first separating device with slide and the resulting rotary movement of the star along with the release of the lever for the spring indicator;

Fig. 3

a representation similar to that after Fig. 2 , but here with the second separating device triggered, the separating element taking the rotary star with it, so that it in turn can release the lever for status display; and

Fig. 4

a perspective view of an overvoltage protection arrangement designed as a plug-in part with a partially broken-away housing and a recognizable housing insert part (upper part) together with a rotary star, lever and the separating element of the second separating device with the detail of a spring contact clip which, when in proper condition, is connected to a contact surface of a gas discharge tube.

The overvoltage protection arrangement shown in the figures is based on a housing 1.

In this housing there is a horn spark gap (not shown) with a deion chamber for arc quenching.

In a manner known per se, the deion chamber has a multiplicity of spaced-apart quenching plates.

A trigger electrode (not shown) is located in the ignition area of the horn spark gap.

Furthermore, a varistor (not shown) is located in the housing 1, which is electrically connected in series with the horn spark gap.

Inside the housing 1 there is a first and a second separation device.

The first separating device 2 is in a thermally conductive connection with the varistor, not shown. When a limit temperature is reached or exceeded, the slide 3 is released, which is supported by a spring 4 on a guide (see FIG Figure 2 ) is stored. In the proper operating state, the electrical connection between contacts 5 and 6 is closed.

If the varistor (not shown) is overloaded (see Figure 2 ) the slide moves in the direction of the arrow. As a result, the slide 3 arrives with its front end in the space between the contacts 5 and 6 with the desired interruption of the relevant circuit.

The slide takes with one of its front edges a first prong 7 of a rotatably mounted star.

As a result, the star rotates in the direction of the arrow, so that the lever 8 is released (see Figure 2 ). The movement of the lever 8 is supported by a further spring 9.

So there is the third star point 10 the lever 8 free.

This enables a remote signaling contact 11 to be triggered or a status display relating to the change in position of the lever 8 with regard to a display window 12 in the housing 1.

Furthermore, there is a second separating device 13 which has a fusible conductor (not shown). This fusible conductor is located in the area of the deionization chamber (not shown) and can be exposed to an arc that occurs there.

The fusible conductor of the second separation device 13 holds a spring-force-assisted separation element 14 in a first position. The spring force assistance is provided by a third spring 15.

After the fusible conductor has melted through the action of an arc or through a line follow current load, the separating element 14 is released. The result is that the separating element 14 as in FIG Figure 3 shown occupying its second position.

When the second position is reached, a related end of the separating element 14 acts on a second prong 16 of the rotatably mounted star.

This is in the Figure 3 shown.

The consequence here is that the rotatably mounted star executes a rotary movement, the third prong 10 of the star executing a position shift and releasing the lever 8 in the same way as this is done using FIG Figure 2 was explained.

The axes of rotation 17 and 18 on the one hand of the star and on the other hand of the lever 8 are at a distance from one another and are parallel to one another.

In the perspective view after Figure 4 it becomes clear that the overvoltage protection arrangement can be designed as a plug-in part with plug connections 20 and 21.

Based on this representation after Figure 4 With the housing partially broken away, a gas discharge tube 22 can be seen which has a contact surface on one of its end faces.

A corresponding spring contact 24 rests with a bracket-side end on the contact surface of the gas discharge tube.

With the movement of the separating element 14 in the direction of the spring clip 24, one end of the separating element slides into the space between the spring clip and the contact surface of the gas discharge tube 22, so that the current flow of the trigger circuit is interrupted. At the same time, as with the Figure 3 explains, the separating element 14 with the prong 16 of the rotatably mounted star to release the lever 8 of the display and error reporting device.

From the representation after Figure 4 It can also be seen that the housing has a first, lower level 26 which accommodates the horn spark gap and the varistor. A second, overlying housing level 27 accommodates at least the separating element 14, the star with its star points, the lever 8 and an actuating extension of the slide 3.

It can be seen from the illustrations that the lever 8 is mounted pivotably by means of the axis 18.

The lever 8 has a bend at a first lever end 81 which releases or covers a display area, an actuating nose for the remote signaling contact 11 being formed on a second lever end 82.

Claims (11)

1. An overvoltage protection arrangement consisting of a horn spark gap accommodated in an insulating housing (1) having a deion chamber for arc quenching, wherein the deion chamber includes a plurality of spaced quenching metal sheets, and a trigger electrode is located in the ignition area of the horn spark gap, furthermore having a varistor electrically connected in series to the horn spark gap,
   characterized in that
   inside the housing (1), a first and a second disconnection apparatus are formed, wherein the first disconnection apparatus (2) is in heat-conducting connection with the varistor, and when a limit temperature is reached or exceeded, releases a spring-loaded slide (3) which interrupts the series connection between varistor and horn spark gap,
   furthermore, the second disconnection apparatus (13) has a fusible conductor located inside the deion chamber, wherein the fusible conductor holds a spring-loaded disconnector element (14) in a first position and releases this disconnector element upon fusing caused by load in such a manner that the disconnector element (14) adopts a second position, wherein an electrical connection to the trigger electrode is interrupted when the second position is reached,
   furthermore, a three-pointed, rotatably mounted star or a disc is formed in the housing (1) such that a first star point (7) is carried along by the slide (3) as it moves to interrupt the series connection, and in the same way, a second star point (16) is carried along as the disconnector element (14) moves from the first to the second position, wherein each entraining movement of the star results in a rotation of the star around its axis of rotation with the consequence that a third star point (10) releases a spring-loaded pivotable lever (8) which operates a remote signaling contact (11) and/or a visual fault status display (12).
2. The overvoltage protection arrangement according to claim 1,
   characterized in that
   the trigger electrode is in connection with one of the main electrodes of the horn spark gap via a voltage limiting element, and said connection being interruptible by means of the disconnector element (14).
3. The overvoltage protection arrangement according to claim 1 or 2,
   characterized in that
   in a first housing plane (26), the housing has the horn spark gap and the varistor, wherein in a second housing plane (27), at least the disconnector element (14), the star (100) und the lever (8) as well as an operating protrusion of the slide (3) are formed.
4. The overvoltage protection arrangement according to claim 2,
   characterized in that
   when reaching the second position, the disconnector element (14) lifts off a spring contact bracket (24) from a contact plate of the voltage switching element (22) and thus interrupts the electrical connection.
5. The overvoltage protection arrangement according to any one of the preceding claims,
   characterized in that
   the slide (3) and the disconnector element (14) consist of an electrically insulating material.
6. The overvoltage protection arrangement according to any one of the preceding claims,
   characterized in that
   the lever (8) is mounted to be pivotable in the housing (1) and, at a first lever end (81), has an angulation which releases or covers a display surface, wherein an operating lug for the remote signaling contact (11) is formed at a second lever end (82).
7. The overvoltage protection arrangement according to claim 6,
   characterized in that
   the axis of rotation (17) of the star (100) and the pivot axis (18) of the lever (8) are parallel to one another.
8. The overvoltage protection arrangement according to claim 7,
   characterized in that
   at least the axis of rotation (17), the pivot axis (18), the star (100) and the lever (8) are components of a housing insert part located in the second housing plane (27).
9. The overvoltage protection arrangement according to any one of the preceding claims,
   characterized in that
   it is formed as a plug-in part with plug contacts (20; 21) for accommodation in a base part.
10. The overvoltage protection arrangement according to any one of the preceding claims,
    characterized in that
    the fusible conductor is contacted to two spaced quenching metal sheets of the deion chamber.
11. The overvoltage protection arrangement according to any one of claims 2 to 10,
    characterized in that
    the voltage switching element is formed as a gas arrester (22).

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