EP2171728B1 - Surge protector having a thermal separating device - Google Patents

Abstract

A surge protector includes a thermal separating device and an error display, and at least two first protection elements, particularly disk-shaped varistors (7), and at least one second protection element, particularly a gas arrester (9), wherein the first and the at least one second protection elements are switched in a Y arrangement. The surge protector further includes a device housing for accommodating the protection elements, and structure, such as a spring (11), for the mechanical biasing of the thermal separating device, wherein the thermal separating device has a low-melting solder, and the first protection elements (7) are disposed in the device housing such that a connection arm of a protection element (7) is positioned opposite the connection arm of the further protection element (7) at a distance, and the thermal separating device is predominantly positioned in the distance space (13) formed in such a manner.

Description

The invention relates to an overvoltage protection device with thermal disconnecting device and fault indication and at least two first protective elements, in particular disk-shaped varistors, and at least one second protective element, in particular gas discharge, wherein the first and the at least one second protection element are connected in Y-arrangement, further comprising a device housing or Support member for receiving the protective elements and means for mechanically biasing the thermal separation device, wherein the thermal separation device comprises a low-melting solder and the first protective elements are arranged in the device housing such that in each case a connecting leg of a protective element facing the connecting leg of the other first protective element with a distance and the Thermal separation device is located predominantly in the distance space thus formed, according to the preamble of patent claim 1.

From the German utility model DE 295 19 313 U1 An overvoltage protection device with thermal cut-off device is previously known. The local surge arrester has a lower part which is electrically connected to inlets and outlets of the system to be protected or the device to be protected. Furthermore, a plug-in part is present, which has at least one varistor. The male part is detachable by a mechanical plug connection with the lower part and thereby electrically connected, wherein on the male part a thermal release is provided in the event of inadmissible heating of the varistor. In the male part is a support wall is located, wherein the varistor are mounted on a side surface of the support wall and the thermal separation device and corresponding switching means on the other side surface of the support wall. The thermal tripping is thus opposite the varistor.

The known plug-in part is formed trough-shaped, wherein the bottom of the tub forms the aforementioned support wall and the tub rim the area surrounds next to the supporting wall, in which the mounted on the supporting wall varistor is located. The varistor itself is equipped with two terminal lugs which serve the electrical connection, one of the terminal lugs being in communication with the thermal tripping element.

In the surge protector after EP 0 727 091 B1 two or more accommodated in a housing varistors are present as protective elements, the ground-line side electrodes are electrically conductively connected to each other by a bar with a contact piece. The network-side electrodes are connected to contact pieces via cut-off devices connected in series with protective elements.

According to EP 0 727 091 B1 the task should be solved to simplify the separation device constructively, without the protective properties are adversely affected.

WO2008 / 068115 relates to a pluggable surge arrester having a housing for receiving the arrester element, which is connected via conductive connectors on plug contacts, which penetrate the housing bottom, wherein between a terminal of the arrester element and the associated connector, a thermal, spring-biased solder separation point is formed.

For this purpose, all separating devices in the pivot region of the web of a pivotally mounted in the housing, substantially U-shaped, designed as a rocker bracket are arranged. At the bridge a slidably mounted in the housing actuating pin is adjacent and continue on the bracket, a display device is arranged. The fact that all separation devices, which are assigned in the overvoltage protection device built-in protective elements associated with a common rocker, the construction is easier. In addition, it is ensured that when opening, i. upon release of the severing device, i. also when triggering only a severing device, the local actuating pin is moved and the trip indicator device comes into a position that makes it clear that an exchange of the surge protection device is necessary.

In the device for protection against the occurrence of transient electrical overvoltages according to EP 0 716 493 B1 At least two varistors are present and there are also provided separating means which are sensitive to the state of the varistors, especially in thermal terms. Each of the varistors can and should be disconnected individually.

In the generic WO 2007/105066 A1 it is an overvoltage protection device, comprising two disc-shaped varistors and a gas arrester, wherein the varistors and the gas arrester are connected in Y-arrangement.

The varistors and the gas arrester are located on a circuit board. In this case, two pins of the varistors are orientated towards each other and there is a metallic electrical bridge which connects the above-mentioned connection legs with the aid of a low-melting solder.

The bridge is held by a spring under bias, the spring is supported with a spring end on a bolt which is fixed on the circuit board.

The separation bridge is connected via a conductor section to the gas discharge tube, wherein in a practical embodiment the conductor section is designed as a flexible stranded wire.

In the case of a thermal overload of the varistors, the melting temperature of the low-melting solder is reached and the bridge moves away from the terminal legs of the varistors, in the separation direction. Also in this solution, as in the other prior art, the provision of an additional separating means is necessary. In addition, there is a risk of unwanted unilateral separation of the bridge.

From the foregoing, it is therefore an object of the invention to provide a further developed surge protection device with thermal separation device and the possibility of error display, the actual separation device should be implemented without additional technical means, without resulting in functional limitations.

The solution of the object of the invention is achieved by a surge protection device with thermal separation device according to the feature combination according to claim 1, wherein the dependent claims include at least expedient refinements and developments.

With the solution according to the invention, it is possible to create an overvoltage protection device in Y-circuit, which consists of a minimum number of components, which is equipped with commercially wired wired protective components and in which no additional disconnecting elements are necessary, where additionally a clear status indicator is present, the can be read in the mains-free state.

As commercially available protective elements Scheibenvaristoren and gas discharge can be used.

In the device housing of the overvoltage protection device are the protective elements and means for mechanically biasing the thermal separator, the thermal separator being a low melting solder or the like means, e.g. Wax, has. The first protective elements are arranged in the device housing in such a way that in each case one connecting leg of a protective element lies opposite the connecting leg of the further protective element with a spacing. The thermal separation device is located predominantly in the spacer space thus formed.

According to the invention, a connection leg of the second protection element, in particular a gas discharge tube, directly bridges the aforementioned connection legs of the first protection elements in the clearance space. In this case, the connection leg of the second protection element is preferably solder-plated with the corresponding connection legs of the first protection elements in the spacer space. On the bridge connecting leg a finger of a mechanically biased Abtrennbocks acts such that in case of overload, the bridge connecting leg is spatially removed from the connecting legs of the first protective elements and thereby results in the desired secure separation from the network.

In a preferred embodiment, the connecting legs of the first protective elements are substantially parallel to one another and are located on one level.

The terminal leg of the second protection element, in one embodiment, has an angling, i. is bent correspondingly, wherein the angled or bent end of the region of the bridge connecting leg, which is connected to the connection legs of the first protective elements forms.

The angled end is oriented substantially perpendicular to the parallel connecting legs of the first protective elements.

The further connecting legs of the first protective elements are connected in the usual way with contact pins or other connection elements of the preferably designed as a plug-in surge protection device in combination.

At least the free ends of the bridged connecting legs of the protective elements and / or the angled end of the bridge connecting leg have a flat, almost flat shape obtained by pressing or similar measure.

In one embodiment of the invention, the disc-shaped first protective elements are located parallel to each other by a wall in the device housing, wherein the separating block is pivotally mounted in the partition wall plane.

The bridge terminal leg is preferably in a position in front of the terminal legs of the first protection element, and the finger of the separation block has an inclined support surface for the bridge connection leg for preventing unilateral separation.

The finger of the Abtrennbocks engages behind the bridge connecting leg at least in a portion of the distance space to ensure safe entrainment in the event of separation.

Below the distance space in the device housing, a free space is provided, which receives in the separation case, the bridge connection leg and the hineinschwenkenden part of the Abtrennbocks.

At the end opposite the finger of the separating trestle, the separating trestle has a display area known per se for detecting states. This surface can be embodied as a colored surface which symbolizes an "OK" state and which, when pivoting, releases an underlying, differently colored surface, which points to the then present error state.

Thus, in summary, the separation point is formed from a wire bridge, which consists of the angled and surface-pressed connecting wire of the second protective element, in particular of the gas arrester, this being connected to a surface-pressed connecting leg of the varistors of the first protective element via the low-melting solder.

Since the separation point consists of the original connecting legs of the protective elements, which are merely shaped for this purpose, no further separating elements or separating means are required.

By the displacement of the wire bridge in front of the Varistoranschlussbeine and the mentioned slope of the Abtrennbocks in the support surface unilateral separation is effectively prevented.

The invention will be explained below with reference to an embodiment and with the aid of figures.

Fig. 1

eine Detailansicht der Abtrennvorrichtung mit den Anschlussbeinen der ersten Schutzelemente und dem im Abstandsraum befindlichen Brücken-Anschlussbein des zweiten Schutzelements;

Fig. 2

eine erste Seitenansicht des Überspannungsschutzgeräts mit vorgespanntem Abtrennbock;

Fig. 3

eine zweite Seitenansicht des Überspannungsschutzgeräts mit vorgespanntem Abtrennbock;

Fig. 4

den Zustand nach Ansprechen der Abtrennvorrichtung in einer Seitenansicht ähnlich derjenigen nach Fig. 2 und

Fig. 5

den Zustand nach erfolgtem Ansprechen der Abtrennvorrichtung in einer Ansicht ähnlich derjenigen nach Fig. 3.

Hereby show:

Fig. 1

a detailed view of the separating device with the connection legs of the first protective elements and located in the spacer space bridge connecting leg of the second protective element;

Fig. 2

a first side view of the overvoltage protection device with biased separation block;

Fig. 3

a second side view of the overvoltage protection device with biased disconnect block;

Fig. 4

the state after response of the separating device in a side view similar to that after Fig. 2 and

Fig. 5

the state after the response of the separating device in a view similar to that after Fig. 3 ,

The surge protection device shown in the figures consists of a base plastic molded part 1, which is surrounded by a cap, not shown figuratively.

In the bottom region 2 of the base plastic molded part 1 breakthroughs for plug contacts 3 are present. Furthermore, a recess 4 is provided to trigger a telecommunications contact depending on the position of the Abtrennbocks 5.

The base plastic molded part 1 has a partition wall 6.

Left and right side of the partition 6 is ever a disc-shaped varistor 7, each having two connecting legs.

A first connection leg of the respective varistor 7 is connected to one of the plug contacts 3.

A second connecting leg extends into a free space 8 within the base plastic molded part 1.

Furthermore, a gas discharge 9 is present. A lead wire 10 of the Gasableiters 9 leads to one of the plug contacts 3. The varistors 7 and the gas discharge 9 are wired in Y-circuit.

The separation block 5 is pivotally mounted on a pin-shaped extension, which is part of the base plastic molded part 1. Furthermore, the Abtrennbock is held by a spring 11 under mechanical bias.

For this purpose, one end of the spring 11 engages in a recess in the separation block 5, wherein the further end of the spring 11 is held on an upstanding projection in the base plastic molded part 1.

To simplify the illustration, the spring 11 in the Fig. 4 and 5 omitted.

The varistors 7 are located on both sides of the partition 6 in parallel position next to each other such that the varistor terminals 12, which do not lead to the plug contacts 3, are substantially parallel to each other and on a plane.

Between the varistor terminals 12 results in a distance space 13th

The spacer space 13 and thus the varistor terminals 12 are bridged directly by a further connecting wire 14 of the gas discharge 9.

This results in a bending of the connecting wire 14, a bridge connecting leg 15, which acts as a separating element readily separate means.

The severance block 5 goes into a finger 16 (see Fig. 5 ) above. With a support surface, the finger 16 presses on the bridge connection leg 15th

The bridge terminal leg 15 is connected to the varistor terminals 12 by a low melting solder.

The varistor terminals 12 are kept very short, so that the bridge connection leg 15 is located close to the varistor and is accordingly thermosensitive.

About the Abtrennbock 5 and the finger 16 acts in conjunction with the spring 11 on the bridge connecting leg 15 a permanent force.

If there is an inadmissible heating of the varistor or varistors 7, the solder acting as a connecting means heats up. As a result, the spring-biased release block 5 moves with fingers 16 as in FIG Fig. 4 and 5 shown, down and pushes the bridge connection leg 15 from the junction between the varistor terminals 12 away, in a safe Abtrennposition.

That in the Fig. 1 Angled end of the connecting wire 14 of the gas discharge conductor 9, which is particularly clearly recognizable, runs essentially perpendicular to the parallel connecting pins 12 of the varistors 7.

The free ends of the varistor terminals 12 and the bridge terminal leg 15 are formed flat, this desired surface shape e.g. can be obtained by a pressing pressure.

The bridge terminal leg 15 is located in front of the varistor terminals 12, which are the first protection elements.

The finger 16 of the separation block 5 still has an inclined support surface 17. By the inclined support surface 17, it is possible in conjunction with the formation of the finger 16, which engages behind the distance space at least in one section, to effectively prevent unilateral separation.

In the separation case, the free space 8 receives the bridge connection leg 15 and the pivoting part of the separation block 5 (see Fig. 4 and 5 ).

The finger 16 opposite end of the Abtrennbocks 5 includes a display area 18th

In proper operating condition (see Fig. 2 and 3 ) obscures the display surface 18 an underlying signal surface 19, which is executed for example in red. In case of error (see Fig. 4 and 5 ), the display surface 18 of the disconnection block 5 moves away from the congruent position with respect to the signal surface 19, so that the signal surface 19 is exposed. A corresponding viewing window in the housing cap, not shown, then makes the signal surface 19 recognizable and the error state clear.

LIST OF REFERENCE NUMBERS

1

Base plastic molding

2

floor area

3

plug contact

4

recess

5

disconnecting

6

partition wall

7

varistor

8th

free space

9

gas arrester

10; 14

Lead wire

11

feather

12

varistor

13

distance space

15

Bridge connecting leg

16

finger

17

Angular contact surface

18

display area

19

signal area

Claims (10)

1. Overvoltage protection device comprising a thermal disconnection device and a fault indicator as well as at least two first protection elements, specifically disc-shaped varistors (7), and at least one second protection element, specifically a gas arrester (9), wherein the first and the at least one second protection elements are interconnected in a Y-arrangement, further comprising a device housing or supporting part for receiving the protection elements and means (11) for mechanically preloading the thermal disconnection device, wherein the thermal disconnection device comprises a low-melting solder or the like means and the first protection elements (7) are arranged such that one connection pin of one protection element (7) is positioned opposite the connection pin of the other protection element (7) at a distance, and the thermal disconnection device is located mainly in the so formed distance space (13),
   characterized in that
   a connection pin (14) of the second protection element (9) directly bypasses the aforementioned connection pins (12) of the first protection elements (7) in the distance space (13) in a solder-contacted manner, wherein a finger (16) of a mechanically preloaded disconnecting component (5) acts on the bypass connection pin (15) in such a way that, in the event of an overload, the bypass connection pin (15) is physically placed away from the connection pins (12) of the first protection elements (7).
2. Overvoltage protection device according to claim 1,
   characterized in that
   the connection pins (12) of the first protection elements (7) extend substantially parallel relative to each other and are disposed on one plane.
3. Overvoltage protection device according to claim 2,
   characterized in that
   the connection pin (14) of the second protection element (9) includes an offset, wherein the offset end forms the region of the bypass connection pin (15).
4. Overvoltage protection device according to claim 3,
   characterized in that
   the offset end is oriented substantially perpendicular to the parallel connection pins (12) of the first protection elements (7).
5. Overvoltage protection device according to one of the preceding claims,
   characterized in that
   at least the free ends of the bypassed connection pins (12) and/or the bypass connection pin (15) of the protection elements have a flat, plane shape obtained by pressing or the like measure.
6. Overvoltage protection device according to one of the preceding claims,
   characterized in that
   the disc-shaped first protection elements (7) are located in the device housing parallel relative to each other and separated by a wall (6), wherein the disconnecting component (5) is mounted in the partition wall plane in a pivotably movable manner.
7. Overvoltage protection device according to one of the preceding claims,
   the bypass connection pin (15) is positioned upstream of the connection pins (12) of the first protection element (7), and the finger (16) of the disconnecting component (5) includes an oblique bearing surface (17) for the bypass connection pin (15) for preventing a one-sided disconnection.
8. Overvoltage protection device according to one of the preceding claims,
   characterized in that
   the finger (16) of the disconnecting component (5) engages behind the bypass connection pin (15) at least in a partial section of the distance space (13).
9. Overvoltage protection device according to one of the preceding claims,
   characterized in that
   below the distance space (13) a free space (8) is provided in the device housing, which receives the bypass connection pin (15) and the part of the disconnecting component (5) pivoting into the same in the event of a disconnection.
10. Overvoltage protection device according to one of the preceding claims,
    characterized in that
    on the end opposite the finger (16) of the disconnecting component (5) the disconnecting component (5) is provided with a display surface (18) for indicating the status.

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