DE102009010227A1 - Tripping device e.g. energy tripping device, has switch that exhibits pressure transducer with electrical output, where electrical output emits electrical signal that is proportional to pressure for operating switching mechanism - Google Patents

Abstract

The device (10) has switching contacts (2, 3) which are separated from each other, if the current flowing via the switching contacts has exceeded a predetermined threshold value. A switch exhibits a pressure transducer with an electrical output, where an electrical output emits an electrical signal that is proportional to pressure (p) for operating a switching mechanism (9). The switch operates the switching off mechanism.

Description

The The invention relates to a trigger for an electrical Switching arrangement which is arranged in the course of a first current path and having at least two switch contacts that can be disconnected when the current flowing through the switch contacts has exceeded a certain threshold. The trigger has an actuator responsive to pressure, in the separation zone of the switching contacts by an electrodynamic recoil of the Switch contacts pulled arc is generated. Pressed the actuator a shut-off mechanism, the automatic interruption of the current path causes.

The The invention further relates to an electrical circuit arrangement with such a trigger.

Generic trigger and switching arrangements with such triggers are for example from the German translation DE 691 10 540 T2 the European patent specification EP 0 455 564 B1 and from the german translation DE 692 17 441 T2 the European patent specification EP 0 538 149 B1 known.

The cited documents DE 691 10 540 T2 and DE 692 17 441 T2 In particular, show a circuit breaker with insulating material, which includes two per pole in the closed position of the circuit breaker resiliently pressed against each other switching contacts. The switching contacts can be separated by the action of electrodynamic recoil forces when the current flowing through the switching contacts exceeds a certain threshold, so as to effect a limitation of said current. The circuit breaker comprises an overload and / or short-circuit detection member for Beauf suppression of an automatic shutdown of the circuit breaker causing in the event of a fault. Furthermore, the circuit breaker comprises an actuator which responds to an overpressure generated in the separation zone of said switch contacts by an arc drawn during electrodynamic recoil of the switch contacts to actuate the circuit breaker of the circuit breaker. The actuator is a gas-tight unit, which is connected exclusively to the separation zone of the switching contacts and a movable element such. B. comprises a piston or a membrane with a limited control stroke. The movable element is acted upon on the one hand with the said overpressure and on the other hand by a return device with adapted effective force. The displacement of the movable element causes the triggering mechanism of the circuit breaker to be triggered, whereby said adapted action force return device is dimensioned to prevent accidental tripping on a single overload or a response of a downstream current limiting circuit breaker.

The shutdown mechanism of the circuit breaker shown is thus triggered both by the overload and / or short-circuit detection member as well as by the independently acting pressure-dependent actuator. The tripping criterion used is the overpressure created when the arc is pulled, which is directly related to the arc energy. In other words, the higher the arc energy, the more the pressure increases. By evaluating the overpressure, an energy-selective shutdown of said circuit breaker is thus possible, wherein the energy selectivity represents a selectivity used in low-voltage networks in particular for shutdown in the short circuit case, as in the document "Energetic Selectivity in Low Voltage Networks", Schneider Electric, Technical Issue No. 167, May 1994 issue is described.

Other generic triggers and generic switching arrangements are from the publications US 3,631,369 A and EP 1 266 387 B1 known. These comprise, for actuating a shut-off mechanism, in each case an actuating member, in the form of a lever, which forms a storage surface in a gas outlet channel. In this case, the actuating member is deflected by a gas flow, which flows as a result of an overpressure generated by the arc in the gas outlet channel.

outgoing from this prior art it is an object of the invention specify an alternative universal deployable trigger.

The The object of the invention is achieved by a trigger with the Characteristics of claim 1 solved. Advantageous embodiments are given in the dependent claims 2 to 4.

According to the invention the actuator a pressure transducer with an electrical outlet on, wherein the electrical output for actuating the shut-off mechanism emits an electrical signal, each proportional to the pressure is.

Of the Advantage of such a trigger and one with a such trigger provided electrical switching device is that the trigger does not use a pure mechanical power transmission chain on the shutdown mechanism acts.

In contrast to the known electrical switching devices described above, in where both the actuator of the trigger as well as overload and / or short-circuit detection members via a common shutoff mechanism set a drive mechanism in motion, which can open only those switching contacts between which the arc was pulled, the trigger according to the invention can also act on a shutdown, the breaks the current path by opening further switching contacts.

In order to is not the trigger of the invention only to improve the switch-off behavior and operational safety suitable for electrical switches, one by itself possess acting means controllable shutdown mechanism, as well as for example, with circuit breakers and contactors the case is. Rather, the inventive Shutter also for switching off electrical switches be used, in which such an automatic Shutdown is not provided, as for example by Disconnectors is known.

In itself is such a universally applicable trigger from the document EP 0 834 184 B1 However, in which, however, an actuator is provided, which responds to an electromagnetic radiation emanating from the drawn between the switching contacts arc. For this purpose, one of the electromagnetic radiation exposed energy converter is arranged in the vicinity of the switch contacts, which converts the received radiation into electricity. In particular, this energy converter has a coil provided with a ferrite core, which generates a high-frequency alternating current which is converted by a rectifier arrangement into a DC voltage suitable for the operation of a triggering magnet.

According to one preferred embodiment of the invention is at the exit of the pressure transducer an electrical or electronic limit level connected, so adjusted in terms of their limit is that they are at a pressure to actuate the shut-off mechanism should lead, an actuation signal at its output generated. With such a limit level are the turn-off an electrical circuit arrangement arranged in a current path and thus also their selectivity behavior in an arrangement controllable in series with other switching arrangements.

To In another embodiment, the actuation signal acts the limit level to an actuator, the input of the actuation signal operated the shutdown mechanism. This preferably electromechanical Actuator may be, for example, a micro-switch.

Around not having to work with two separate components it is advantageous if the limit level in the pressure transducer is integrated.

The Invention and advantageous embodiments of the invention will be described below with reference to the following figures. Show it

1 a schematic representation of an electrical circuit arrangement with a pressure-responsive trigger according to the invention and

2 and 3 Schematic representations of two embodiments of the trigger according to the invention.

The 1 shows an electrical circuit arrangement 1 in the form of a designed as a circuit breaker individual switching device.

Such, usual Way single or multi-pole circuit breaker trained For example, in the low voltage range - ie up to voltages of about 1000 volts - to break one or more poles Currents in a short circuit or in an overcurrent case used. You can per pole one or more pairs of switching contacts and are in particular for switching off currents of more than 100 A, in particular of several kA.

That's how it shows 1 two switching contacts 2 . 3 of the circuit breaker, the interruption of a first current path 4 serve a first switching pole. A mobile one 2 the switching contacts is of a rigid contact member 5 worn and in a closed position shown here in dashed lines resiliently against a stationary 3 the switching contacts pressed. For receiving the switching contacts 2 . 3 the first switching pole is a through a housing 6 limited first switch room 7 intended. A drive mechanism 8th serves to open and close the switching contacts 2 . 3 , In the course of this drive mechanism is a shut-off mechanism 9 arranged in the form of a switching mechanism.

In the first switch room 7 is due to an electrodynamic recoil of the switch contacts 2 . 3 drawn arc LB generates a pressure p, under the action of a pressure responsive trigger 10 as a pressure sensing element tripping the shutdown mechanism 9 - So a release of the latching of the switch lock - causes the drive mechanism 8th for opening the switch contacts 2 . 3 to get started.

The trigger 10 forms a designated among professionals as a trigger pressure form of an energy release, in which the fact is exploited that in the separation zone of the switch contacts generated pressure p is substantially proportional to the energy of the drawn arc LB.

In the electrical switching device are next to the trigger 10 also a thermal trigger 11 as an overload detection element, an electromagnetic release 12 as a short-circuit detector and a manual release 13 provided by means of which the switching mechanism in case of failure - ie overload or short circuit - can be solved to open the switch contacts.

As overload and / or short-circuit detection member may substitute or in addition also be provided an electronic trigger. Naturally can the electrical switching device also have other triggers, such as having an undervoltage release.

The electrical switching device has in a manner not shown in parallel to that in the 1 shown switching room 7 more switching rooms, in which switching contacts further switching poles are arranged.

Two preferred embodiments of the trigger according to the invention are described below with reference to FIG 2 and 3 explained in more detail.

In the 2 illustrated embodiment 210 the trigger has a pressure sensor as a pressure sensor 14 with an electrical outlet 15 on. Such a pressure transducer is at its electrical output 15 an electrical signal which is proportional to the pressure p. Such pressure transducers, which are also referred to as industrial pressure transducer, are usually with a threaded connector 16 provided and can therefore in the illustrated manner directly into a corresponding threaded hole 17 provided wall 18 of the switch room 7 be screwed limiting housing. This can be done in particular in a section of the control room in which arc quenching plates are arranged and which is therefore also referred to as arc quenching chamber.

To the electrical outlet 15 of the pressure transducer 14 is an electrical or electronic limit value level 19 connected, which is set in terms of their limit that they at a pressure p, which is to lead to the actuation of the shutdown, an actuation signal at its output 20 generated. With this actuation signal becomes an actuator 21 , For example, a micro-switch or the like acted upon, which actuates the shut-off mechanism upon receipt of the actuating signal.

In the context of the invention are modifications to the in 1 shown embodiment possible.

So shows 3 a second embodiment 310 the trigger of the invention. Here are those components that are in the 1 and 2 Components shown are identical or substantially functionally identical, denoted by the same reference numerals. In this second embodiment 310 the trigger is the limit level 319 in the pressure transducer 314 integrated, so you do not have to work with two components. Also this pressure transducer 314 has an - unspecified here - electrical output, which is followed by the limit stage.

In addition, according to the 3 in the second embodiment 310 the trigger of the pressure transducer 314 via a pressure line 22 with the switch room 7 or the arc-quenching chamber forming portion of the switch room connected. It is therefore not necessary to introduce the pressure transducer into the wall of the control room.

Further Optionally, a microswitch can be dispensed with if the possibility exists of a suitably executed Shutdown mechanism directly with the output signal of the limit value stage to act on.

Of the Trigger according to the invention offers technical seen the advantageous way to him by simple Change of the limit value adjustable with the limit value level to adapt to different circumstances. The required components are commercially available, so that the trigger overall a reasonably producible Alternative to the known triggers forms.

In addition, the use of the trigger according to the invention is not limited to switching devices that have a controllable by automatically acting means shut-off mechanism. So he is in the same way as already in the publication EP 0 834 184 B1 described trigger much more universal use.

Of the For example, trigger can also be hand-held be associated with actuated disconnector, wherein the pressure transducer in an electrodynamic recoil of the switching contacts of the Disconnector, in the separation zone of these switch contacts by detected the pressure generated by the arc. That from the output of the pressure transducer generated electrical signal is then used for example for actuation a shut-off mechanism connected in series with the circuit breaker Circuit breaker.

Furthermore, the shutter can also be a contactor be assigned, wherein the pressure transducer detected in an electrodynamic recoil of the switching contacts of the contactor, the pressure generated by the arc. The electrical signal generated by the output of the pressure transducer then serves, for example, for actuating a drive magnet of the contactor.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 69110540 T2 [0003, 0004]
• EP 0455564 B1 [0003]
• - DE 69217441 T2 [0003, 0004]
• - EP 0538149 B1 [0003]
• - US 3631369 A [0006]
• - EP 1266387 B1 [0006]
• - EP 0834184 B1 [0013, 0036]

Cited non-patent literature

• - "Energetic Selectivity in Low Voltage Networks", Schneider Electric, Technical Issue No. 167, May 1994 Edition [0005]

Claims (5)

Trigger ( 10 ; 210 ; 310 ) for an electrical switching arrangement ( 1 ), which in the course of a first flow path ( 4 ) is arranged and the at least two switching contacts ( 2 . 3 ), which are separated when the current flowing through the switching contacts has exceeded a certain threshold value, with an actuator which is responsive to a pressure (p) in the separation zone of the switching contacts ( 2 . 3 ) is generated by a drawn in electrodynamic recoil of the switch contacts arc (LB), and a the automatic interruption of the current path causing shutdown mechanism ( 9 ) actuated, characterized in that the actuating member is a pressure transducer ( 14 ; 314 ) with an electrical outlet ( 15 ), wherein the electrical output ( 15 ) for actuating the shut-off mechanism ( 9 ) emits an electrical signal which is in each case proportional to the pressure (p). Trigger according to claim 1, characterized in that to the output ( 15 ) of the pressure transducer ( 14 ; 314 ) an electrical or electronic limit value level ( 19 ; 319 ), which is set in terms of its limit value so that it, at a pressure (p), which is to lead to the actuation of the shut-off mechanism, an actuating signal at its output ( 20 ; 320 ) generated. Trigger according to one of claims 1 or 2, characterized in that an actuator ( 21 ) is provided, wherein the actuating signal of the limit stage ( 19 ; 319 ) on the actuator ( 21 ) acting on the input of the actuation signal the shutdown mechanism ( 9 ). Trigger according to one of claims 1 to 4, characterized in that the limit value level ( 319 ) in the pressure transducer ( 314 ) is integrated. Electrical switching arrangement ( 1 ) with at least one electrical switching device, the two switching contacts ( 2 . 3 ), which in the course of a first flow path ( 4 ) are arranged and which can be separated when the on the switch contacts ( 2 . 3 ) flowing current has exceeded a certain threshold, and with a trigger ( 10 ; 210 ; 310 ) to interrupt the first flow path ( 4 ), characterized in that the trigger ( 10 ; 210 ; 310 ) is designed according to one of claims 1 to 4.