EP0804800B1 - Protection switching devices with a device for forcible separation of main supply lines in protection switching devices - Google Patents

Abstract

All switching devices which have the purpose of protecting people or objects from the harmful effects of electric current include at least triggering elements which trigger the appropriate switching mechanisms whenever predetermined threshold values are exceeded. This opens the main current contacts in the switching device, thus usually stopping current flow. However, such switching devices occasionally fail in an emergency situation because, for example, the trigger elements stick, the switching mechanisms jam, the contacts become welded together, or because of other faults. For such eventualities, a device is proposed for forcibly interrupting the appropriate mains or main current lines with a work storage unit. The latter produces a force along a pathway and is kept in an inactive state by a locking mechanism. The locking mechanism can easily be released by a trigger controlled by the switching device and the work storage unit can thus be freed to switch to its active state. A separator device driven by the work storage unit then forcibly separates the current lines. The device is especially suitable for incorporation in or combination with protective switches such as fault current protective switches, automatic cut-outs, bus protection switches, motor protection switches, power protection switches and the like.

Description

All switching devices that protect people and / or things from dangerous effects of the to protect electrical current, such as residual current circuit breakers, Miniature circuit breakers, main circuit breakers, motor circuit breakers, Circuit breakers and the like contain triggers that are fault currents or overloads or Detect short circuits and then switchgear if limit values are exceeded trigger. Thereupon the main current contacts of the switching devices open, so that normally no harmful electricity can flow.

But it happens that such switching devices fail in an emergency because, for example, their Stick the trigger, clamp the switchgear, the contacts are welded or others There are defects. The persons and / or things to be protected in this case are especially at failure of a residual current circuit breaker, significantly endangered.

From DE-A 42 11 079 there is already an electrical fuse element, in particular High-current fuse element known, in which a circuit to be secured switched power conductor is destroyed when the amperage reaches a threshold exceeds. Here, the strength of the current flowing through the conductor is one Current detection device determined that after exceeding the threshold Conductor by means of an ignition pulse generating device and a pyrotechnic operated separator destroyed. The aim of this arrangement is that of conventional Fusible fuses are usually made using a thicker conductor replace to reduce power loss. Due to this, when the threshold values of these current conductors matched to the associated nominal current strength do not destroy yourself by melting, but it must be mechanically destroyed by a Device are separated.

From document US-A-2757259 a forced device is known Disconnect mains or main power lines, using a working memory that is a force provides along a path and that by means of a ratchet in an inactive Condition is maintained, with a shutter release with little effort triggerable and thus the RAM can be released so that it from the inactive in passes its active state, one driven by the working memory Disconnect device in the triggered state, the forced separation of the network or Main power lines.

The invention is based on the object in the event of failure of the Switching devices mentioned above, in particular for residual current circuit breakers, a Device for the forced and very quick disconnection of the associated network or Show main power lines, in order to endanger people and / or things to exclude.

This object is achieved by a device with the features of Claim 1 solved. Further developments and advantageous refinements of the invention are specified in the subclaims.

a) einen Arbeitsspeicher, aus dem eine Kraft über einen Weg zur Verfügung gestellt werden kann. Solche Arbeitsspeicher können beispielsweise sein:

• vorgespannte Federn, wie zylindrische Schraubenfedern, Spiral- oder Drehfedern.
• Druckspeicher, in denen ein Arbeitsmedium komprimiert gehalten wird, welches bei Expansion mittels eines Kolbens eine Kraft über einen Weg zur Verfügung stellt.
• Gasgeneratoren, wie sie bereits in Airbag- und Gurtstraffersystemen eingesetzt werden. Diese erzeugen ein Gasvolumen, das dann mittels eines Kolbens eine Kraft über einen Weg zur Verfügung stellt.

b) ein Gesperre, welches den Arbeitsspeicher mit geringem Kraftaufwand in seinem inaktiven Zustand hält. Solche Gesperre können sein:

• Hebel, Kniehebel, Klinken- oder Riegelgesperre, sowie andere Mittel, die jeweils formschlüssig wirksam sind.
• reibschlüssig wirkende Gesperre.

c) einen Auslöser, der das Gesperre löst und damit den Arbeitsspeicher freigibt. Auslöser können sein:

• eine vorgespannte Feder, die durch einen dünnen Draht gehalten wird. Dieser Draht kann eventuell eine Sollbruchstelle aufweisen und wird solange gehalten, bis er durch einen Strom geschmolzen wird.
• eine Einrichtung, die eine Bewegung eines Körpers aus elektrischen Kräften erzeugt. Dies kann ein Elektromagnet sein, aber auch die Coulombsche Kraft, der Kondensatoreffekt, der Johnsen-Rhabeck-Effekt oder auch der Versuch von Elihu Thomson können die Bewegung des Körpers erzeugen.
• ein Strom, der einen Treibstoff aktiviert.

d) eine Trenneinrichtung, die vom Arbeitsspeicher angetrieben die Trennung der Leitungen übernimmt. Die Trennung der Netz- oder Hauptstromleitungen kann geschehen durch:

• Öffnen von Kontakten
• Zerschneiden von Leitungen
• Zerstören von Leitungen.

The device essentially has the following elements:

a) a working memory from which a force can be made available in one way. Such working memories can be, for example:

• preloaded springs such as cylindrical coil springs, spiral or torsion springs.
• Pressure accumulators in which a working medium is kept compressed, which provides a force via a path when expanded by means of a piston.
• Gas generators, such as those already used in airbag and belt tensioner systems. These generate a gas volume, which then uses a piston to provide a force over a path.

b) a locking mechanism which keeps the working memory in its inactive state with little effort. Such locks can be:

• Levers, toggle levers, ratchet or bolt locks, as well as other means, which are each positively effective.
• frictionally acting locking mechanism.

c) a trigger that releases the locking mechanism and thus releases the working memory. Triggers can be:

• a preloaded spring that is held by a thin wire. This wire may have a predetermined breaking point and is held until it is melted by a current.
• a device that generates movement of a body from electrical forces. This can be an electromagnet, but also the Coulomb force, the capacitor effect, the Johnsen-Rhabeck effect or the attempt by Elihu Thomson can produce the movement of the body.
• a stream that activates a fuel.

d) a separation device that drives the separation of the lines driven by the working memory. The mains or main power lines can be separated by:

• Open contacts
• Cutting lines
• Destroy lines.

The particular advantage of the device according to the invention is that it is direct in circuit breakers of the type mentioned at the beginning or as an additional device with these in series can be arranged. In the circuit breakers with suitable conventional Current measuring systems in particular measured the fault, overload or short-circuit currents and these measured values are also used by the device. Exceed the measured values a predetermined limit value and the respective circuit breaker does not switch within a certain time, the network or Main power lines separated. So basically the existing regular fails Protection function of the switchgear for different reasons, so the Device easily reliable and within a certain harmless Time the live lines. This forced separation of the lines is normal a unique and irreversible process, so that after that at least the circuit breaker or the switching device must be replaced and the device reactivated.

Fig. 1 bis 7

zeigen die Vorrichtung lediglich schematisch, jeweils mit Arbeitsspeicher, Gesperre und Auslöser und das Zusammenwirken dieser Baugruppen, während in

Fig. 8 bis 15

von der Vorrichtung mögliche Formen der Trenneinrichtung ebenfalls nur schematisch dargestellt sind, wobei eine Kombination dieser Elemente mit den Baugruppen nach Fig. 1 bis 7 im Sinne der Erfindung beliebig realisiert werden kann.

The invention is explained in more detail below using various exemplary embodiments with reference to the drawing.

1 to 7

show the device only schematically, each with memory, lock and trigger and the interaction of these assemblies, while in

8 to 15

Forms of the separating device which are possible from the device are likewise only shown schematically, a combination of these elements with the assemblies according to FIGS. 1 to 7 being able to be implemented as desired in the sense of the invention.

In the device according to FIG. 1, a spring accumulator is provided as the working memory interacts with a lever lock and a fuse wire as a trigger. Are there in a pot-shaped housing 1 a compression spring 2 and above a piston 3 with a Tappet 3.1 arranged, which represent the essential parts of the spring accumulator. Means a lever 4 mounted in the housing 1, which acts on the upper side of the piston 3 compress the compression spring 2 so that it is under spring tension. This biased position of the compression spring 2 (as already shown in Fig. 1) is by means of a Lever 4 attacking and anchored to the housing 1 fuse wire 5 reliably held. Due to a relatively short lever arm for point 4.1 of the lever there is also a favorable gear ratio, based on the Fastening point of the fuse wire, which should be made accordingly thin In spite of sufficiently large forces and travel of the compression spring 2 and corresponding Conditions on the piston 3 or plunger 3.1 can be such a thin fuse wire melted by a current in the shortest possible time and thus the working movement of the Ram 3.1 be initiated very quickly.

The function of the assembly of the device described above is as follows: Are the specified limit values of fault current, overload or short-circuit current exceeded and the circuit breaker, not shown here, has within the required time is not triggered, the measuring devices of the circuit breaker trigger current passed to the fuse wire 5, which causes it to melt. Immediately lever 4 released and under the action of the tensioned compression spring 2, the piston 3 also moves its plunger 3.1 upwards or away from the housing 1. With this Ram movement is then over the separators to be described in more detail 8 to 15 mains or main power lines of the circuit breaker forcibly Cut.

The device according to FIG. 2 is designed in a similar manner. Here is in that pot-shaped housing 1, however, a tension spring 2 'as a spring accumulator on the piston 3 or hung on the housing. The mainspring is in the range of The knee levers 4 'which engage the spring eyelets and are arranged in the interior of the spring, as in FIG shows. So that the toggle lever 4 'its almost extended position and thus the spring tension can maintain, it is also locked by a fuse wire 5. This is with One end preferably attached to the toggle joint and the other end to the Shell surface of the housing held and led out. Another tension spring 6, whose direction of action and points of attack roughly correspond to the position of the fuse wire, supports the latter in his task. The tension spring 6 is considerably weaker designed as the tension spring 2 '. Nevertheless, the tension spring 6 relieves the fuse wire 5 considerably, so that it can be made much thinner than in Embodiment according to Fig. 1. Its operation is analogous here also applicable, that is after the destruction of the fuse wire 5 by one Tripping current drives the tension spring 2 'the plunger 3.1 and this ultimately one Separator.

The device according to FIG. 3 is also designed with a toggle lever. Here serves as Spring accumulator in turn a compression spring 2 against the toggle lever 4 'via the piston 3 the bottom of the housing 1 is clamped. The almost stretched location of the as a ratchet attacking above the piston and supported on the top of the housing The toggle lever 4 'is again secured by the fuse wire 5, which is also here together with a tension spring 6 prevents the knee lever from buckling. The This device also functions in the manner already described.

In Fig. 4 a device is shown which, in contrast to the previous arrangements has a latch. For the rest, there is also a pot-shaped housing 1 here Compression spring 2 arranged as a working memory, which is tensioned by the piston 3. In the pestle 3.1 there is a recess into which a bolt 7 engages, which is located on the top supports the housing 1 and thus locks the plunger in the position shown. Also stops a fuse wire 5, the bolt 7 in engagement with the plunger recess, while one on Tension spring 7.1 engaging the bolt against the holding force of the fuse wire tried to unlock.

This device operates in the manner already described, that is, according to The spring 7.1 pulls through the melting wire 5 due to a tripping current the bolt out of the recess of the plunger 3.1. The inactive position of the Working memory canceled and then under the action of the compression spring 2 the plunger 3.1 upwards and drives a separating device for forced separation of the power lines.

Furthermore, the device can be provided with a pressure accumulator as a working memory be as shown by way of example in FIGS. 5 and 6. Doing so will result in the accumulators Working medium - preferably air - kept compressed and at first by a locking mechanism prevented the expansion.

5 is in the housing 1, which is pressure-resistant is formed, a compressed working medium 8 enclosed by the piston 3. This is by means of a toggle 4 '- similar to the devices of FIGS. 2 and Fig. 3 - locked against the pressure of the working medium, with a fuse wire 5 as well prevents the knee lever from buckling. If the fuse wire is destroyed, there is Toggle the piston 3 free and the compressed working medium 8 can expand, so that the plunger 3.1 moves away from the housing and the one already mentioned Separation device actuated.

The construction of the device according to FIG. 6, in which one chamber of the Housing 1 for receiving the compressed working medium 8 through a valve 9 is closed. The valve is loaded by a compression spring 9.1 in the opening direction also held against this force by a fuse wire 5, so that the chamber remains tightly sealed with the compressed working medium. Above the In turn, a piston 3 with the plunger 3.1 is arranged in the valve chamber. After a Destruction of the fuse wire 5 by a trigger current opens the valve 9 under the Effect of the compression spring 9.1 and the working medium 8 can escape into the valve chamber. From there it flows under the bottom of the piston 3, which thus carries out the working stroke and again actuated a separating device with the plunger 3.1.

The device according to FIG. 7, in which the main memory is used, is significantly different in design is designed as a pyrotechnic gas generator and is automatic, that is without one actual locking mechanism, is in the inactive state. This device is in the housing 1 a fuel 8 'arranged with a primer 8.1 and through a gas permeable Wall 1.1 of the housing included towards the piston 3. If a trigger current on the Given the primer, the fuel 8 'is activated and a gas volume is generated. This flows under the bottom of the piston 3 and drives it together with the plunger 3.1 upwards in order to include one of the separation devices described below actuate.

8 to 15 separating devices of various types are shown. So be 8 contacts 10 and 11, which in the course of a network or Main power line 12 are connected in series, pressed together by spring force. In front the contacts a wedge-shaped insulating body 13 is arranged, which is part of the Plunger 3.1 can be one of the working memories already described. In the case of one over The isolating body 13 is triggered and main memory initiated forced separation immediately pressed between the contacts 10, 11 and opens them. The network or main power line 12 in the course of the corresponding circuit breaker, not shown forcibly interrupted.

9 shows two disconnecting devices by means of additional contacts 10 ', 11' and 10 ", 11" shown in the course of the mains or main power line 12 arranged by the plunger 3.1 of the working memory can be opened.

In Fig. 10 switching contacts 14, 15 are shown schematically by a circuit breaker are arranged in series with the line to be protected. Should these switch contacts in Triggered case, for example, be welded, so they are only here indicated plunger 3.1 of the working memory forced open. On In this way, the forced interruption of the mains or main power lines can be done directly in the switchgear.

Another form of separation device is shown in FIG. 11. Here are in line with one Line L1 arranged a contact sleeve 16 and a contact pin 17 which interlock and connect the two line ends together. The contact pin 17 also forms the Tappet tip 3.1. The piston of the working memory is shown in the The direction of the arrow moves so far that it removes the contact pin 17 from the contact sleeve 16 has pushed out and the insulating part 3.1 'of the plunger is in the sleeve, so line L1 interrupted.

Separators for several lines, which are similar in construction to FIG. 11, show schematically the Fig. 12 / 12a and Fig. 13. In the separation device of FIG. 12 and its Side view Fig. 12 a are on an enlarged insulating part 3.1 'of the Tappet two pairs of contacts 17 'arranged at right angles, each on corresponding counter contacts 16 'of the lines L1 and L2 work on the circumference. By Moving the plunger 3.1, as indicated by an arrow in Fig. 12a, come opposing contact pairs in the insulating part 3.1 'and the peripheral Mating contacts out of engagement, so that the lines L1 and L2 are interrupted.

13 are around an insulating part 3.1 "of the plunger in the axial Three contact pairs for the lines L1, L2, L3 offset one behind the other arranged. If the plunger 3.1 is moved in the direction of the arrow shown, so the contact pins 17 ″ arranged in the insulating part disengage from both sides mating contacts 16 ″ arranged therefrom. The path of the plunger and thus also to limit the piston so that in the interrupted state a sufficient Distance or offset between the contact pins 17 "in the insulating part and Mating contacts 16 "of the three lines remain. In this respect, the Distances of the three contact pairs only by a schematic arrangement.

14 and 15 are separators in which the lines are irreversibly interrupted. 14 is a line schematically 12, which has a predetermined breaking point 12.1. The predetermined breaking point is arranged that it comes to face the end of the plunger 3.1. As soon as the piston of the RAM is moved in the direction of the arrow, the plunger strikes 3.1 with its forehead formed as an insulating part, the line 12 at the predetermined breaking point and separates them forcibly.

In the arrangement according to FIG. 15, the line 12 is uniform throughout Cross section on, whereas the tip of the plunger 3.1 knife-like is trained. The plunger directed at right angles to the line also cuts through a line movement relevantly driven by the working memory with the line 12 the knife edge. The available forces and ways of working memory With such an arrangement, of course, the cross-section and the required shear forces of the line 12 must be coordinated.

The separating devices of the exemplary embodiments according to FIGS. 8, 14 and 15 each show only the mechanical separation from a line. With simultaneous separation from A corresponding number of isolating devices must be provided for several lines and distribute the drives of the working memory to these separation points. Next to them are Maintaining memory and separators in a sensible way.

Claims (15)

1. Protective circuit breaker device with an apparatus for forcible separation of the mains or primary current lines (12, L1, L2) with

   a) an energy store (2, 2', 8, 8'), which makes available a force along a way and which is held in an inactive condition by means of a catch mechanism (4, 4', 7),

   b) whereby the catch mechanism (4, 4', 7) is capable of being triggered by means of a trigger (5, 6, 7.1, 9.1) with little effort and thus the energy store (2, 2', 8, 8') is releasable, so that it changes from the inactive to its active condition, and

   c) whereby a separating apparatus (3.1, 13) driven by the energy store (2, 2', 8, 8') brings about in its triggered condition the forcible separation of the mains or primary current lines (12, L1, L2), whereby

   d) the apparatus for forcible separation is provided within the circuit breaker device or in an additional housing arranged in series with the circuit breaker device,

   e) the trigger is controlled by a trigger current of the circuit breaker, and

   f) the trigger current is only fed to the apparatus for forcible separation on failure of the circuit breaker device.
2. Protective circuit breaker device according to Claim 1,
   characterised in that
   energy stores in the form of springs (2, 2') or pressure stores (8) or gas generators (8') are used as drive for the forcible separation of the lines (12, L1, L2).
3. Protective circuit breaker device according to Claim 1,
   characterised in that
   catch mechanisms in the form of levers (4) or toggle levers (4'), or latch-type or bolt-type catches (7) hold the energy store (2, 2', 8, 8') in the inactive condition until triggered.
4. Protective circuit breaker device according to Claim 1,
   characterised in that
   the trigger has a pretensioned spring (6, 7.1, 9.1), which is held by a thin wire (5) possibly provided with a predetermined breaking point, until the wire is melted by a current initiating the forcible separation.
5. Protective circuit breaker device according to Claim 1,
   characterised in that
   the trigger is designed in principle as an electromagnet or other body moved by reason of electrical effects.
6. Protective circuit breaker device according to Claim 1,
   characterised in that
   in the separating apparatus, the forcible separation is brought about by means of opening of contacts (10/11, 14/15, 16/17) or cutting or destruction of lines (12).
7. Protective circuit breaker device according to one of the claims 1 to 6,
   characterised in that
   with one energy store (2, 2', 8, 8'), separating devices are driven for the simultaneous forcible separation of one or more lines (L1, L2, L3), for instance the phase lines and the neutral line.
8. Protective circuit breaker device according to one of the claims 1 to 7,
   characterised in that
   the separating apparatus for the mains or primary current lines (12, L1, L2) is arranged within the circuit breaker.
9. Protective circuit breaker device according to one of the claims 1 to 7,
   characterised in that
   the separating apparatus for the mains or primary current lines (12, L1, L2) is situated in an additional housing arranged in series with the circuit breaker.
10. Protective circuit breaker device according to one of the claims 6 to 9,
    characterised in that
    the separating apparatus is provided with a wedge-shaped insulating body (13) that can be pushed between two contacts (10, 11) of the mains or primary current lines (12), respectively (Fig. 8).
11. Protective circuit breaker device according to one of the claims 6 to 9,
    characterised in that
    the separating apparatus (3.1) has a knife, preferably an insulated knife, with which the mains or primary current lines (12) can be cut through (Fig. 15).
12. Protective circuit breaker device according to one of the claims 6 to 9,
    characterised in that
    a predetermined breaking point (12.1) in the mains or primary current lines (12) can be broken by an insulated striker (3.1) arranged in the separating apparatus. (Fig. 14).
13. Protective circuit breaker device according to one of the claims 6 to 9,
    characterised in that
    the separating apparatus (3.1) has arranged in the mains or primary current lines (L1, L2, L3) a contact pin (17) capable of being withdrawn from a contact sleeve (16) (Fig. 11, 12, 13).
14. Protective circuit breaker device according to one of the claims 6 to 9,
    characterised in that
    for forcible separation of the mains or primary current lines, the existing switch contacts (14, 15) of the protective circuit breaker can be struck open by means of the separating apparatus (3,1) (Fig. 10).
15. Protective circuit breaker device according to one of the claims 6 to 9,
    characterised in that
    the separating apparatus (3.1) is designed as contact of a second contact site (10', 11' or 10", 11") in the mains or primary current lines (12) (Fig. 9).

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