EP1369890A1 - Indicator striker device for high voltage fuse - Google Patents

Abstract

Striking alarm system comprises: a housing (13); a spring (16) with a moving end arranged in the housing; actuator (17) leading from the housing and interacting with the moving end; a high ohmic resistance wire (12) connected in parallel to a melting wire of a fuse; and a holder receiving a pre-tension of the spring. The holder contains a section of the resistance wire formed as a coil (18). Striking alarm system comprises: a housing (13); a spring (16) with a moving end arranged in the housing; actuator (17) leading from the housing and interacting with the moving end; a high ohmic resistance wire (12) connected in parallel to a melting wire of a fuse; and a holder receiving a pre-tension of the spring. The holder contains a section of the resistance wire formed as a coil (18). The section of the wire is guided around the moving end of the spring forming a pre-tension and is in partial contact with the material of the activator. Independent claims are also included for the following: (1) high voltage fuse with a striking alarm system; and (2) switch-fuse system with a high voltage fuse.

Description

TECHNICAL AREA

The invention starts with a field detector system for a High-voltage fuse according to the preamble of claim 1. A such a field detector system has various functions. For one thing this system for that in any way, be it visual, acoustic and / or electrical, it is reported that the high voltage fuse due to the from the Fuse currents and / or the prevailing ambient temperature has triggered. On the other hand, the system can also be used to in a circuit with a switch-fuse combination in the circuit interrupt the current by triggering the switch. Under High voltages are to be understood as nominal voltages greater than 1 kV, but in particular nominal voltages up to approx. 100 kV. The invention also relates to a high-voltage fuse with this impact detector system and a switch-fuse system with this fuse.

STATE OF THE ART

With the preamble, the invention takes on a prior art Detector systems reference, as described in the HTB - 11/97 "HH fuse links with temperature limiter "from SIBA fuse construction GmbH, Borker Strasse 22, D-44534 Lünen. One in this Release alarm system described is used in fuses for Medium voltage switchgear, i.e. at nominal voltages of typically 10, 20 or 30 kV, used and has a cylindrical symmetrical Housing on, in which a preloaded coil spring and one inside the Coil spring guided and pre-tensioning pin thermoplastic material are arranged. An upward-facing end of the biased spring is supported on a lower end of a bolt-shaped Detector, the upper end of which is led out of the housing. A parallel to a fuse wire of the fuse is switched high-resistance wire guided around the housing in a heat-conducting manner. The thermoplastic stick works as a melting activator, which is above a predetermined limit temperature melts and thereby a relaxation of the spring and thus a triggering of the Impact detector. This enables the melt activator to be activated that the temperature in the fuse due to internal influences, such as long-lasting overcurrents, or external influences, such as the supply of heat through the switchgear or by radiation above the limit temperature. On the other hand, the melt activator can also be activated in that the Limiting a current flowing in the fuse from that of the low-resistance Fuse wire of the fuse in the high-resistance wire commutating current the melt activator quickly to the limit temperature heating up.

The activator which activates the previously known field detector system consists of thermoplastic material. However, a thermoplastic has in generally has a very wide temperature range in which initially by softening and later by crystallite melting the strength properties of the material are gradually reduced. Therefore, a wide spreading behavior cannot be excluded with certainty when triggering this field detector system.

PRESENTATION OF THE INVENTION

The invention, as defined in the claims, solves the problem To indicate the stroke detector system of the type mentioned at the beginning, which simple means to safely trigger a high-voltage fuse in one allows relatively narrow temperature range.

In the impact detector system according to the invention, the biasing force of the spring picked up by a section of the high-resistance Resistance wire, which at least once to form the bias a movable end of the spring is guided, and which at least partially in is thermally conductive contact with the material of the activator. Through this Measures become a spread when the field alarm system is triggered significantly reduced because the activator no longer has the holding force for the preloaded spring has to be applied, but only by the holding force Remove the wire winding. Since the subject of the invention these two functions are decoupled, the activator no longer has to be one have sufficient strength to fix the preloaded spring. The activator can therefore be made of one material regardless of its strength exist, which in a narrow temperature range the lifting of the Holding force of the prestressed spring effecting phase transition. It triggering is subject to only slight scattering with simple means of the field detector system reached.

If the activator has a high energy material with one above the Limit temperature releasable amount of energy that is sufficient to the wire winding melting, then a limit temperature can be reached, which at most fluctuates by approx. ± 10 ° C. A correspondingly small spread then shows the field detector system provided with such an activator according to the Invention on. Particularly suitable high-energy materials contain one Fuel, such as in particular a guanidine or a guanidine derivative, one Reaching the limit temperature with the fuel, releasing the energy reacting oxidizer, such as in particular a nitrate, chlorate, perchlorate and / or Permanganate, and optionally a binder, such as paraffin in particular or a polymer. These high-energy materials are described in DE 100 22 41 A1.

A particularly simple run detector system is achieved if the Activator mechanically fixes the wire winding. After the activator is triggered the point fixation is canceled and the turns of the winding opened while releasing the spring. In one for one The activator is particularly advantageous for mass production executed and fixes the wire winding on the spring. Contains the activator an alloy melting at the limit temperature, especially based Silver, copper and / or aluminum, doped with indium and / or germanium, see above has the field detector system according to the invention because of only a few ° C fluctuating melting temperature a particularly small spread at Trigger on. In addition, by changing the doping ratio in simpler Way a change in the melting temperature of the alloy and thus the Trigger characteristics of the field detector system can be achieved. suitable Alloys are described in the aforementioned DE 100 22 241 A1.

A particularly compact design of the field detector system according to the Invention is achieved when the spring is designed as a coil spring and with a fixed end arranged opposite the movable end is supported on the housing, and if the bias from that to the movable and the fixed end of the spring guided wire winding is included.

DESCRIPTION OF THE DRAWINGS

Fig. 1

eine Aufsicht auf eine geschnitten dargestellte Hochspannungssicherung mit einem schematisch dargestellten Schlagmeldersystem nach der Erfindung,

Fig. 2

eine Aufsicht auf eine teilweise geschnitten dargestellte erste Ausführungsform des Schlagmeldersystems gemäss Fig.1, und

Fig. 3

eine Aufsicht auf eine teilweise geschnitten dargestellte zweite Ausführungsform des Schlagmeldersystems gemäss Fig.1.

The invention is explained below using exemplary embodiments. It shows:

Fig. 1

1 shows a plan view of a high-voltage fuse shown in section with a schematically illustrated impact detector system according to the invention,

Fig. 2

a top view of a partially sectioned first embodiment of the field detector system according to Fig.1, and

Fig. 3

a top view of a partially sectioned second embodiment of the impact detector system according to Fig.1.

WAYS OF CARRYING OUT THE INVENTION

In the figures, the same parts are identified by the same reference numerals. The High-voltage fuse 1 shown in FIG. 1 has a hollow cylindrical shape and generally designed as a ceramic housing 2, in which in coaxial Arrangement of a support body 3, which also generally consists of ceramic is kept fixed. On the support body 3 are helical wound, low-resistance fuse element 4 arranged, the ends of which with one attach to the lower end of the housing 2, cap-shaped Power connector 5 are connected and the other with one at the top of the housing 2 attach cap-shaped power connector 6. The Power connector 6 has an opening 7 through which one in the direction of Housing axis 8 movable part (not shown in Fig.1) of a Power connection 6 attached impact detector system 9 is feasible. This part works with a switch 10 connected in series with the high-voltage fuse 2 a switch-fuse system 11 together. Inside the Fuse housing 2 is also a led into the impact detector system 9, high-resistance wire 12 provided. This wire is with both Power connections 5 and 6 connected and thus parallel to the fuse element 4 connected.

The structure and mode of operation of the field detector system are from Figures 2 and 3 removable. It can be seen from these figures that the A coaxial alarm system for securing a generally has metallic housing 13, whose lower end as a taper 14 and whose upper end is designed as a widening 15. Inside the case 13, a preloaded coil spring 16 is arranged. The coil spring 16 sits with its lower end on the taper 14 and carries on its upper movable end an actuator designed as a cap 17. The power of biased spring 16 is through a winding 18 of the high impedance Resistance wire 12 added, the turns of which from the movable end the spring to the opposite fixed end are.

In the embodiment of Fig. 2, the two by the bias fixed ends of the winding 18 with a crimping element 19, and is a high energy material, such as a, inside the housing 13 Mixture of 30 weight percent diguanidinium 5,5'-azotetrazolate, 3.5% Percent by weight guanidine nitrate and 66.5 percent by weight potassium permanganate, having activator 20 provided. This material decomposes in one Temperature of approx. 177 ° C and releases an amount of energy of 862 J / g. The activator 20 is at least partially in thermally conductive contact with the Wire winding 18 and embeds at least one for manufacturing reasons Part of the spring 16 a.

Fuse 1 heats up due to external (external energy) or internal (Backup current) effects at approx. 177 ° C, so the high-energy material decomposes and releases energy, which with suitable mass dimensioning is sufficient to melt the wire winding 18. The coil spring 16 can now relax and guides the actuator 17 with its movable upper end through the widening 15 and the opening 7 (FIG. 1) from the fuse housing 2 and thus reports the response of the impact detector system 9 in an optical manner. At the same time, the actuator 17 can be opened by striking a trigger element of the switch 10 its opening and thus switching off one in the switch-fuse system cause flowing current.

An activation of the field detector system when limiting one in the fuse 1 flowing fault current is achieved in that the fault current after it has interrupted the low-resistance wire 4 by melting, in the high-resistance resistor wire 12 commutated parallel path and the The wire is now very hot. Since the activator 20 is in thermally conductive contact with The wire winding 18, which is now very hot, activates the activator quickly Decomposition temperature of 177 ° C and the winding through it decomposing high energy material while releasing the moving end of the Coil spring 16 and by pulling the actuator 17 out of the fuse 1 destroyed.

In the embodiment of the impact detector system according to FIG. 3, the activator 20 mechanically fixes the wire winding 18. This is achieved by a small drop of an alloy melting at the desired limit temperature, for example Agln ₂ with a melting temperature of 166 ° C., which fixes the wire winding 18 on the spring 16 in the form of a point, or which fixes two sections of the winding 18 which can be displaced relative to one another , When the melting temperature of approx. 166 ° C. is reached, the wire winding 18 is released from the spring 16 or the displaceable winding sections are separated from one another and the windings of the winding 18 can now open while simultaneously releasing the spring.

LIST OF REFERENCE NUMBERS

1

High voltage fuse

2

casing

3

support body

4

low-resistance fuse wire

5, 6

power connectors

7

opening

8th

axis

9

Shock detector system

10

switch

11

Switch-fuse system

12

high resistance wire

13

casing

14

rejuvenation

15

widening

16

Spring, coil spring

17

actuator

18

wire winding

19

crimping

20

activator

Claims (10)

Impact detector system (9) for a high-voltage fuse (1) with a housing (13), a spring (16) arranged in the housing (13) with a movable end, an actuator (17) which can be guided out of the housing (13) and cooperates with the movable end, a high-resistance wire (12) connected in parallel to a fuse wire (4) of the fuse (1), and with a holder which absorbs the pretension of the spring (16) and which can be removed with the aid of an activator (20) above a limit temperature while simultaneously relieving the spring (16), characterized in that the holder contains a section of the high-resistance wire (12) which is designed as a winding (18) and which is guided around the movable end of the spring (16) at least once to form the pretension, and which is at least partially in thermally conductive contact with the Material of the activator (20) is. Impact detection system according to claim 1, characterized in that the activator (20) comprises a high-energy material with an amount of energy that can be released above the limit temperature, which is sufficient to melt the wire winding (18). Impact detection system according to Claim 2, characterized in that the high-energy material is a fuel, such as in particular a guanidine or a guanidine derivative, an oxidizer which reacts with the fuel when the limit temperature is reached, releasing the energy, such as in particular a nitrate, chlorate, perchlorate and / or permanganate, and optionally a binder, such as in particular a paraffin or a polymer. Impact detection system according to one of claims 2 to 4, characterized in that at least part of the spring (16) is embedded in the high-energy material. Impact detection system according to claim 1, characterized in that the activator (20) mechanically fixes the wire winding (18). Impact detection system according to claim 5, characterized in that the activator (20) is punctiform and the wire winding (18) is fixed on the spring (16). Impact detection system according to one of claims 1 to 6, characterized in that the activator (20) is formed from an alloy melting at the limit temperature, in particular based on silver, copper and / or aluminum, doped with indium and / or germanium. Impact detection system according to one of claims 1 to 7, characterized in that the spring is designed as a helical spring (16) and is supported on the housing (13) with a fixed end arranged opposite the movable end, and in that the pretensioning of the movable one and the fixed end guided wire winding (18) is received. High-voltage fuse (1) with a blow detection system (9) after a of claims 1 to 8. Switch fuse system (11) with a high-voltage fuse (1) according to claim 9.

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