WO2017148638A1

WO2017148638A1 - Tripping mechanism and electromechanical safety switch

Info

Publication number: WO2017148638A1
Application number: PCT/EP2017/051985
Authority: WO
Inventors: Bernhard Franz; Thomas Rieger; Winfried Vierling
Original assignee: Siemens Aktiengesellschaft
Priority date: 2016-03-03
Filing date: 2017-01-31
Publication date: 2017-09-08
Also published as: DE102016203508B4; DE102016203508A1

Abstract

The claimed tripping mechanism (100) for an electromechanical safety switch (1), for example for a circuit breaker or power switch, has a solenoid coil (101) in addition to an armature-tappet assembly which comprises an armature (102) and a tappet (103) and which can be moved relative to the solenoid coil from a resting position into a tripped position by means of said solenoid coil (101). The tripping mechanism (100) also has a retaining system (110) coupled to the armature (102) and acting on the latter in order to retain the armature in its resting position under electric currents that remain below a predefined current threshold value. The retaining system (110) is designed such that the armature (102) is completely released when the predefined current threshold value is exceeded. The retaining device (110) is consequently decoupled from the armature (102) and from this point in time no longer exerts a force on the armature (102) which would push the latter back into its resting position. As a result of the decoupling of the retaining device (110) from the armature (102), the retaining device from this point in time no longer exerts a force on the armature (102) which would push the latter (102) - and thus the armature-tappet assembly - back into its/their resting position. The reaction time of the tripping mechanism (100) - and thus the switching capacity of the safety switch (1) - can thereby be significantly improved.

Description

description

The invention relates to a tripping device for an electro-mechanical protection device, such as a circuit breaker or circuit breaker, which a solenoid, an armature plunger assembly comprising an armature and a coupled to the armature plunger, by means of the magnetic coil relative to this of a holding position, which is coupled to the armature and acts thereon to hold the armature plunger assembly until it reaches a predefined current threshold value in its rest position. Furthermore, the invention relates to an electro-mechanical protection device with such a triggering device.

Various types of protective switching devices are known from the prior art: Circuit breakers are designed especially for high currents. A circuit breaker (so-called circuit breaker) is an overcurrent protection device used in electrical installations and is used in particular in the area of low-voltage networks. Circuit-breakers and circuit-breakers guarantee a safe shutdown in the event of a short circuit and protect consumers and electrical equipment from overload, for example, from damage to the cables due to overheating as a result of excessive electrical current. Circuit breaker and circuit protection switches are used in particular as switching and safety elements in electrical energy supply networks and serve to monitor and secure an electrical circuit. For this purpose, the protective switching device is electrically connected via two terminals with an electrical line of the circuit to be monitored in order, if necessary, in this line to interrupt flowing electrical power. The protective switching device in this case has a switching contact with a stationary fixed contact in the housing and a movable relative to movable contact. The moving contact is actuated via a switching mechanism of the protective switching device, so that the switching contact can be opened and closed by means of the switching mechanism. In this way, when a predefined state, for example a short circuit or an electrical overload, occurs, the switching contact is opened in order to disconnect the monitored circuit from the electrical line network. Such protective switching devices are known in the field of low-voltage technology as DIN rail mounted devices. From the patent DE 10 2004 040 288 B4 a circuit breaker is known, which has a first triggering device for detecting and switching off a short circuit and a second triggering device for detecting and switching off an overload condition. Furthermore, the circuit breaker has a switching contact with a fixed contact and a moving contact that is movable relative thereto, as well as a release lever which is coupled to both the first triggering device and the second triggering device such that upon triggering of the first triggering device and / or the second triggering device. th triggering device of the release lever is actuated and thus the switching contact is opened. When opening the switch contact arises between the fixed contact and the moving away moving contact first an arc, which is deleted in the further course to permanently interrupt the flow of current.

In order to interrupt the flow of current when a short circuit occurs, the first triggering device is designed as a magnetic triggering system with a magnetic coil and a relatively movable armature plunger assembly. The current path of the electric current, which flows from one of the terminals to the switching contact of the protective switching device, thereby leads via the magnetic coil, which exerts an electromagnetic force on the armature plunger assembly in the energized state. With a rapid increase in the electrical current, as occurs in the case of a short circuit, the magnetic coil of the magnetic trip system is energized with the high short-circuit current, whereby the armature is pulled into the coil. The armature plunger assembly is thereby moved from its rest position to its released position. As a result, the ram firmly connected to the armature is moved from its rest position to its released position. Here, the plunger meets the release lever, which is thereby also moved. By actuating the release lever, the switching mechanism of the protective switching device is released, whereby the moving contact coupled to the switching mechanism is moved away from the fixed contact in order to open the switching contact and thus the

Interrupt current flow via the switching contact. In this way, a first trip chain, consisting of plunger, trip lever and moving contact is realized. A triggering mechanism with such a triggering chain is known for example from DE 10 2004 040 288 B4.

In order to prevent the armature plunger assembly from being pulled into the magnet coil even with permissible operating currents, a so-called armature spring is used. This has the task of holding the armature-and thus the entire armature-tappet assembly-against the magnetic force of the magnetic release, ie the energized magnetic coil, up to a predefined force threshold in its rest position. This force threshold, which marks the response range of the magnetic release, corresponds to a predefined, maximum permissible current threshold, at which point the magnetic release triggers. However, the use of an armature spring has the disadvantage that this spring opposes the movement of the armature from its rest position to its released position with progressive deflection of the armature in accordance with the Hook's spring law in accordance with an ever greater spring force. In other words, when triggering the armature spring will move the armature - and thus the armature plunger assembly - into its released position, the resistance of the armature spring against this movement increasing according to the hook's law, as the path increases. To achieve a high switching capacity, however, it is necessary to open the switching contact as quickly as possible in order not to increase the short-circuit current even further. By using an armature spring, which counteracts with increasing force when triggering the movement of the armature, the goal of the shortest possible response time of the magnetic trip system - and thus the highest possible switching capacity of the protective device - adversely affected. It is therefore an object of the present invention to provide an improved tripping device and an improved electro-mechanical protective switching device, which are characterized by a shorter reaction time, and thus by a higher switching capacity.

This object is achieved by the tripping device according to the invention and the electromechanical protective switching device according to the invention according to the independent claims. Advantageous embodiments are the subject of the dependent claims.

The tripping device according to the invention for an electromechanical protective switching device, for example for a circuit breaker or a circuit breaker, has a solenoid coil and an armature plunger assembly, comprising an armature and a plunger, which by means of the magnetic coil relative to this from a rest position into one Triggered position is movable on. Furthermore, the triggering device has a holding device which is coupled to the armature and acts on the armature in order to apply it to the armature

Keep currents below a predefined current threshold in its rest position. The holding device is included such that the armature is completely released when the predefined current threshold value is exceeded.

The holding device holds the armature - and thus the armature plunger assembly - in its / its rest position, as long as the current flowing through the solenoid electrical current does not exceed the predefined current threshold. When the current threshold value is exceeded, the armature is completely released by the holding device, i. The holding device is decoupled from the anchor and exerts no more force on the anchor from this point on, which would force the anchor back to its rest position. The holding device thus serves as a replacement for the armature spring, wherein only the function of holding the armature in the rest position, but not the function of returning the armature is realized in its rest position after the release by the holding device. In this way, the movement of the armature from its rest position to its released position counteracts no spring force caused by an armature spring. As a result, the reaction time of the tripping device - and thus the switching capacity of the protective switching device - significantly improved.

In an advantageous development of the triggering device, the armature has at its distal end at least one coupling point, which cooperates with a coupling element of the holding device to form a mechanical coupling. With the help of the coupling point of the anchor is fixed, but releasably coupled to the holding device, ie in the coupled state - below the predefined current threshold - is a predefined force, which the movement of the armature plunger assembly from its rest position to its tripped position counteracts, transferable from the holding device to the anchor, whereas in the uncoupled state - above the predefined current threshold value - none of the movement movement of the armature from the rest position to the released position counteracting force is exerted by the holding device on the armature. The term "distal end" is to be understood as the rear end of the armature in the direction of movement from the rest position into the released position.

In a further advantageous development of the triggering device, the coupling point as a latching groove and the coupling element as a resilient latching element, which engages in the rest position in the latching groove formed.

A latching connection represents a simple and cost-effective possibility for realizing a positive but releasable mechanical coupling between the holding device and the armature. The armature is conventionally rotationally symmetrical. The latching groove formed at the anchor can be adapted to the resilient latching element formed on the holding device both in sections and peripherally, for example as a circumferential groove. In the rest position, the resilient latching element engages in the latching groove in order to keep the armature-and thus the armature-plunger assembly-in its rest position at electric currents below the predefined current threshold value against the magnetic force of the energized solenoid coil , On the spring stiffness of the resilient locking element and a defined by the interaction of locking element and locking groove geometric line of action, the tripping characteristic of the triggering device to a certain maximum holding force - and thus to the predefined current threshold - adjustable.

In a further advantageous development of the triggering device, the latching element is designed as a leaf spring, whose one free end engages in the rest position in the latching groove. A leaf spring provides a simple and inexpensive way for the structural design of the locking element. The free end of the leaf spring engages in the rest position in the locking groove formed on the anchor to keep the anchor in its rest position. Instead of a single leaf spring, it is also possible to use a plurality of leaf springs to more accurately adjust the maximum holding force of the holding device can. In a further advantageous embodiment of the triggering device, the latching element is designed as an annular spring, which engages in the rest position in the latching groove.

The use of a ring spring provides a further simple and inexpensive possibility for the structural design of the latching element. The latching groove is advantageously designed as a circumferential groove. The annular spring engages - similar to a locking ring or Nutenring - over a larger peripheral portion away in the circumferential locking groove to keep the armature at electric currents below the predefined current threshold in its rest position.

In a further advantageous development of the triggering device, the latching element is designed as a U-shaped bent spring element whose two free ends engage in the rest position in the latching groove.

The U-shaped bent spring element has two spring legs and a connecting web connecting the two spring legs. In the rest position of the armature or the armature plunger assembly, the two free ends of the two spring legs engage in the locking groove to hold the armature in its rest position. The detent groove may be circumferentially or in sections, with two sections for the two free ends of the two spring legs, be formed. In a further advantageous embodiment of the triggering device, the latching element is designed as a spring-loaded latching ball, which is pressed in the rest position into the latching groove.

Another possibility for constructive design of the locking element is the use of one or more spring-loaded detent balls, which is pressed in the rest position of the armature or the armature plunger assembly in the locking groove or pressed to the armature at currents below to keep the predefined current threshold in its rest position. The locking groove is designed as a groove, for example, with a hemispherical recess formed. By using one or more spring-loaded locking balls, the maximum holding force of the holding device is metered adjustable.

In a further advantageous development of the triggering device, the armature has a chamfer in the region of its distal end.

A bevel is to be understood as a bevelled area. The armature, which is conventionally rotationally symmetrical, thus has a tapered cross-section in the region of its distal end. On the one hand, when the holding device is released as a result of an electric current flowing above the current threshold value, the resilient coupling element initially jumps out of the latching groove and then moves in the direction of its released position on the outer surface of the armature during movement of the armature

Direction of the distal end slides. As soon as the spring-loaded coupling element has reached the region of the chamfer, the armature is additionally accelerated in the direction of its triggering position due to the spring force exerted by the coupling element on the armature. On the other hand, the chamfer serves as

Inlet slope, in order to return the anchor to its Reduction reloading the holding device with the anchor easier.

In a further advantageous development, the triggering device has a mechanical adjustment element in order to adapt the triggering device to the predefined current threshold value.

With the aid of the adjustment element, the triggering device can be adapted to the predefined current threshold value. Furthermore, the triggering device with the aid of the adjustment element can also be adapted to different current threshold values. In this way, one and the same trip device for protective switching devices with different tripping characteristics can be used.

In a further advantageous embodiment of the triggering device, the adjustment element is designed as an adjusting screw, such that upon actuation of the adjusting screw, the position of the coupling element is variable.

An adjusting screw provides a simple and cost effective way to constructively realize the

By adjusting the adjusting screw, the position of the coupling element relative to the coupling point of the armature is precisely adjusted, so that the coupling force acting in the coupled state as accurately as possible to the assigned, predefined current threshold value can be adjusted.

In a further advantageous embodiment, the triggering device has a mechanical energy storage, which urges the armature plunger assembly when exceeding the predefined current threshold in the direction of its tripped position.

With the help of the additional power storage, the reaction time of the release device - and thus the switching capacity of the protective switching device - further improved. The energy storage is, for example, as a spring, which is supported against a fixed part of the protective switching device - for example, the housing or another, stationary in the housing assembly - realized, and causes the anchor - and thus the armature plunger assembly - is also accelerated in the direction of its tripped position when the predefined current threshold is exceeded. In a further advantageous refinement, the triggering device has a rear-part device, which is designed to reset the armature plunger assembly back into its rest position after a fall below the predefined current threshold value due to the interruption of the current path.

With the help of the rear-part device, it is ensured that the tripping device - and thus the protective switching device - is returned to a ready-to-trip state after tripping. Advantageously, the rear part device is mechanically realized; However, non-mechanical implementation options are not excluded per se. In a further advantageous development of the triggering device, the rear subassembly has a mechanical force accumulator which urges the armature ram assembly from its released position into its rest position. This may be, for example, a return spring, which pushes back the armature plunger assembly after its release from its tripped position to its rest position. However, this return spring is not equivalent to an armature spring, even if it should be arranged in the same position: An armature spring is used, the armature at electrical currents below the predefined current threshold against the magnetic Force the solenoid to keep in its rest position. An armature spring is therefore much stronger to dimension and therefore has a much higher spring hardness. Normally, an armature spring holds the armature plunger assembly in its rest position with a force of approximately 0.3 to 7 Newton. In contrast, the return spring is dimensioned with a much lower spring rate, as to reset the armature only frictional forces and possibly - depending on the installation position - to overcome gravity, but not exerted by the energized magnetic coil on the armature strong magnetic forces. Therefore, the return spring exerts only a force of about 0.2 Newton on the armature plunger assembly in its rest position. In a further advantageous development of the triggering device, the restoring device has a reset lever, which can be mechanically coupled to a switching mechanism of the protective switching device, so that the armature can be returned to its rest position by means of the reset lever coupled to the switching mechanism.

An alternative possibility for the realization of the restoring device is a so-called reset lever. This is mechanically coupled to the switching mechanism of the protective device and acts in the coupled state at a distal end of the armature opposite the second end of the armature plunger assembly such that this is pushed back from its released position to its rest position. When using such a restoring device, the armature plunger assembly - and thus the magnetic coil - are designed to be much more compact, which is particularly advantageous for circuit protection devices with a width of only one division unit. In a further advantageous development of the triggering device, the holding device is formed from a bimetallic strip or a shape memory material. Under a bimetallic strip or a shape memory material materials are to be understood, which change their shape in a defined manner with a change in temperature. Thermo-mechanical or shape-memory materials are used in electromechanical circuit-breakers in order to trigger the protective switching device when an overload current occurs: The overload current flowing over a long period heats the bimetallic strip or the shape-memory material and deforms in a predefined manner. This change in shape is transferred to the switching mechanism, whereby a triggering of the switching mechanism - and thus the protective switching device - is realized. By using such a material for the holding device, the functionality of the thermal overload release can be integrated into the short-circuit tripping device according to the invention - a separate overload tripping device is thus dispensable. Furthermore, this makes possible an extremely compact design of the protective switching device.

The electromechanical protective switching device according to the invention, for example a circuit breaker or a circuit breaker, has a tripping device of the type described above.

With regard to the advantages of the electromechanical protective switching device according to the invention, reference is made to the above statements on the advantages of the tripping device according to the invention.

Embodiments of the tripping device or of the electromechanical protective switching device will be explained in more detail below with reference to the attached figures. In the figures are: characters

1 and 2 are schematic representations of a first embodiment of the tripping device according to the invention or of the inventive electro-mechanical protection switching device in a first switching state;

characters

3 and 4 are schematic representations of the first embodiment of the tripping device or of the electro-mechanical protective switching device in a second switching state;

characters

5 and 6 are schematic representations of the first embodiment of the tripping device or of the electro-mechanical protective switching device in a third switching state; characters

7 and 8 are schematic representations of a second embodiment of the triggering device in different switching states; characters

Figures 9 and 10 are schematic representations of a third embodiment of the tripping device in different switching states; characters

11 to 15 are schematic representations of different embodiments of the holding device.

In the various figures of the drawing, like parts are always provided with the same reference numerals. The description applies to all drawing figures in which the corresponding part can also be recognized. In FIGS. 1 to 6, a first exemplary embodiment of the tripping device 100 according to the invention or the electromechanical protective switching device 1 according to the invention is shown schematically in three different switching states. The

Figures 1, 3 and 5 show the open circuit protection device 1 to the three respective switching states in a side view; in the corresponding Figures 2, 4 and 6, the corresponding, corresponding to the individual switching states tripping device 100 is shown in detail in corresponding side views.

The protective switching device 1 has a housing 2, in which the individual components of the protective switching device 1 are received and supported. About a mounting side 12 is the

Housing 2 on a holding element - for example, a support or DIN rail - attachable. On one of the attachment side 12 opposite front side 11 of the housing 2, the protective switching device 1 has a rotatably mounted actuating element 3 for manual actuation of the protective switching device 1. The actuating element 3 is mechanically coupled via a coupling bracket 7 with a switching mechanism of the protective switching device 1. With the switching mechanism, a moving contact carrier 8 is also mechanically coupled. At the Bewegkontaktträger 8 a moving contact 5 is arranged, which together with a fixedly arranged in the housing 2 fixed contact 4 a

Switching contact 6 forms. With the help of Bewegkontaktträgers 8, the moving contact 5 can be moved relative to the fixed contact 4, whereby the switching contact 6 can be opened or closed.

Furthermore, an input terminal 9 and an output terminal 10 are arranged in the housing 2, via which the protective switching device 1 is connectable to an electrical line to interrupt the current flow in this line in the event of a short circuit or overload. For tripping in case of overload, a thermal tripping device, which is presently designed as a bimetallic element 20, received and held in the housing 2 of the protective switching device 1. The bimetallic element 20 deforms at a predefined temperature increase and is mechanically coupled to the switching mechanism such that it is triggered when a predefined deformation is exceeded.

For interrupting the electric current in the event of a short circuit, a tripping device 100 is arranged in the housing 2. It has a magnetic coil 101, which is electrically conductively connected to the input terminal 9 via a stranded wire 13. Furthermore, the triggering device 100 has an armature-plunger assembly, consisting of an armature 102 and a fixedly connected to the armature plunger 103, on. The armature plunger assembly is slidably mounted relative to the solenoid 101 and movable by energizing the solenoid 101 from a rest position to a released position. During the movement of the armature plunger assembly in the released position of the plunger 103 hits with its distal, the armature 102 remote from the end of a trigger lever 19 of the switching mechanism, whereby the switching mechanism is triggered and the switching mechanism coupled with the switching contact 6 is opened.

Below the triggering device 100, an extinguishing chamber 14 is arranged in the housing 2, which is formed from a multiplicity of extinguishing plates 15 oriented parallel to one another and spaced apart from one another. The quenching chamber 14 serves to extinguish an arc which arises during the opening of the energized switching contact 6 by moving away the moving contact 5 from the fixed contact 4. If the switching contact 6, which is likewise arranged in the antechamber region 18, is opened, then the arc first burns between the fixed contact 4 and the moving contact 5 which moves away with increasing distance of the moving contact 5 From the fixed contact 4, the voltage of the arc continues to increase until the arc from the moving contact 5 to a likewise arranged in Vorkammerbereich 18 guide rail 17 commutes, ie skips. On the side of the fixed contact 4, the arc travels along a contact horn 16 arranged below the fixed contact 4 in the direction of the extinguishing chamber 14. When striking the extinguishing chamber 14, the arc is transformed into a plurality of partial arcs connected in series, ie electrically in series, between the individual extinguishing plates 15 burn, split. As a result, the arc voltage continues to increase until the arc finally stops and goes out.

The first switching state shown in FIGS. 1 and 2 is characterized in that the actuating element 3 is in an OFF position and the switching contact 6 is opened accordingly. The armature plunger assembly is in its rest position. In this switching state, the current path which leads to the output terminal 10 from the input terminal 9 via the tripping device 100 to the switching contact 6 and further via the moving contact carrier 8 and the thus electrically conductively connected bimetal element 20 when the switching contact 6 is closed (see FIG ,

3 and 4 show the protective switching device 1 and the tripping device 100 in a second switching state, which may also be referred to as "tripping ready state." The actuating element 3 is in an ON position, the switching contact 6 - and thus the current path between the input terminal 9 and the output terminal 10 - are closed accordingly The armature plunger assembly is ready to trigger and is accordingly in its rest position.

In FIGS. 5 and 6, the protective switching device 1 and / or the tripping device 100 are shown in a third switching state, immediately after a triggering of the tripping device 100 has occurred. This third switching state can also be referred to as "tripped state." The armature ram Assembly was spent from its rest position to its triggered position, whereby the switching contact 6 has already been hit a little way by the plunger 103. The triggering of the switching mechanism is already initiated by the movement of the armature plunger assembly from its rest position to its triggering position, but the switching mechanism itself has not yet responded thereto due to its inertia, which is why the actuating element 3 is still in its ON position. Position is. Only when the switching mechanism completely triggers, the switching contact 6 as shown in Figure 1 - fully opened and spent the actuator 3 via the coupling bracket 7 in its OFF position.

The triggering device 100 further includes a holding device 110, which is fixedly arranged in the housing and with the

Anchor 102 is mechanically coupled. The holding device 110 is presently designed as a U-shaped bent spring element and has two spring legs 111 and the two spring legs 111 interconnecting connecting web 112. At their free end, the two spring legs 111 each have a coupling element 114, which are each coupled to an armature 102 formed, the respective coupling element 114 associated coupling point 104. The coupling points 104 are formed as a kind of locking groove, in which the two engage at the free ends of the spring legs 111 formed as locking nubs coupling elements 114. In this way, a positive coupling between the holding device 110 and the armature 102 is realized, which is structurally designed such that the armature 102 - and thus the armature plunger assembly - at electrical currents below a predefined current threshold in his / her Rest position is held positively.

When the predefined current threshold value is exceeded, for example when an electrical short circuit occurs, the electromagnetic force which is dependent on the magnetic coil 101 energized by the short-circuit current ker-plunger assembly is exerted and acts in the direction of triggering position, greater than the force exerted by the retainer 110 on the armature 102 and acting in the opposite direction holding force. As a result, the positive connection between the armature plunger assembly and the retainer 110 is released by the U-shaped retainer 110 is bent by the resultant force. In this case, the coupling elements 114 designed as latching nubs are pulled out of the coupling points 104 assigned to them, designed as latching grooves, whereby the form-locking effect hitherto acting in the direction of movement of the armature-plunger assembly is resolved. Due to the spring force of the U-shaped holding device 110, the coupling elements 114 designed as latching nubs initially form a frictional contact with the armature circumferential surface. Since the armature 102 is chamfered in the region of its distal end, ie is tapered, the armature plunger assembly is additionally in the direction of its release position by the pressure exerted by the holding device 110 due to their spring force on this portion of the armature 102 accelerated. In his further movement in the

Triggered position, the armature 102 is then fully released, i. the retainer 110 exerts no force on the armature 102 which would urge the armature plunger assembly towards its rest position. This state is shown in FIGS. 5 and 6.

In order to set the holding force to be exerted by the holding device 110 on the armature 102, the holding device 110 further has a locking screw 113 configured as an adjusting screw

Adjustment element on. The adjusting screw 113 is supported in the housing 2 of the protective switching device 1 and arranged such that it acts on the connecting portion 112 of the holding device 110. If the adjusting screw 113 tightened, so a pressure on the connecting portion 112 is exercised, which leads to a concave deformation, ie a deflection of the connecting portion 112. Due to this deflection, the two to the connection portion 112th molded spring leg 111 pressed apart. The compressive force exerted by the coupling elements 114 formed as latching nubs on the coupling points 104 designed as latching grooves is thereby reduced. The predefined current threshold value, from which triggering of the tripping device 100 takes place, is thereby correspondingly reduced. Conversely, by loosening the adjusting screw 113, the deformation of the concave connecting portion 112 can be reduced. The compressive force which is exerted by the coupling elements 114 designed as latching nubs on the coupling points 104 designed as latching grooves is thereby reinforced, as a result of which the triggering threshold value is correspondingly raised.

In the illustrations of FIGS. 1 to 6, the current path from the input terminal 9 via the first strand 13 to the first spring leg 111 of the holding device 110 and further via the connection region 112 and the second spring leg 111 by means of a second strand 115 to the magnet coil 101 However, it is also possible to connect the input terminal 9 directly to the magnetic coil 101 by means of a single strand or a rigid connection.

In order to return the armature plunger assembly from the released position shown in FIGS. 5 and 6 to the rest position shown in FIGS. 1 to 4, the protective switching device 1 also has a rear part device, which in FIGS. 1 to 6 serves as a reset lever 121 is formed. The reset lever 121 is rotatably mounted in the housing 2 of the protective switching device 1 and L-shaped in the representations of Figures 1 to 6. However, this shape is not mandatory for the basic operation of the reset lever 121, other forms are also possible. A first leg of the L-shaped reset lever 121 is in operative connection with the plunger 103, wherein no force is exerted on the plunger 103. The other, second leg is in operative connection with the rotary roller of the actuating element 3rd In the "switch-ready" second switching state illustrated in FIGS. 3 and 4, the end of the first leg bears against an end face of the plunger 103, thereby defining a first end position of the reset lever 121. A second end position of the reset lever 121 is shown in FIG The armature plunger assembly is in its tripped position immediately after triggering of the triggering device 100. As a result of the pressure of the plunger 103 on the first leg of the L-shaped reset lever 121, the reset lever 121 has been moved by approximately 15 ° As soon as the switching mechanism of the protective switching device 1 has responded to the triggering of the tripping device 100, the switching contact 6 is opened and the actuating element 3 is moved via the coupling bracket 7 into its second position.

Position spent (see Figure 1). In this case, the reset lever 121 is returned to its first end position by means of a return contour 21 formed on the rotary roller of the actuating element 3.

FIGS. 7 and 8 schematically show a second exemplary embodiment of the tripping device 100 according to the invention in two different switching states. 7 shows the triggering device 100 in the "ready to trigger" state, the armature plunger assembly is correspondingly in its rest position The retaining device 110 is connected to the armature 102 via the two coupling elements 114 formed as latching nubs at the free ends of the spring legs 111 It is coupled in a form-locking manner via its coupling points 104 designed as latching grooves and holds it in its inoperative position. <br/> Figure 8 shows the triggering device 100 in the "triggered" state, the armature plunger assembly is accordingly in its released position. Accordingly, the holding device 110 is no longer positively coupled to the armature 102. The armature plunger assembly is thus completely released, ie the holding device 110 is decoupled from the armature 102 and exerts no force at this time on the anchor-ram assembly, which would force these back into their rest position.

In contrast to the first embodiment shown in FIGS. 1 to 6, the rear part device, which serves to return the armature plunger assembly to its rest position, is not a reset lever in the second embodiment shown in FIGS Return spring 122 is formed. The return spring 122, which is designed as a helical spring, is arranged to save space around the plunger 103 around and against a magnetic yoke 22, which is arranged stationarily in the housing 2 of the protective switching device 1, supported. The return spring 122 is a weakly dimensioned helical spring whose spring force is sufficient only to return the armature plunger assembly from its released position in its rest position. During this restoring operation, no magnetic forces act on the armature plunger assembly, since at this time the switching contact is opened and the solenoid coil 101 is de-energized accordingly.

The relocking of the holding device 110 at the distal end of the armature 102 when returning the armature plunger assembly to the rest position is facilitated or supported by the bevel 105 formed at the distal end of the armature 102. By the chamfered bevel 105, the spring legs 111 are pressed apart when returning the armature plunger assembly, so that the two formed at the free ends of the spring legs 111 as latching nubs Koppelele- elements 114 with the form of locking grooves formed coupling points 104 of the armature 102 form fit can be coupled. Due to its weak spring force, the return spring 122 is by no means suitable for holding the armature plunger assembly in its rest position against the electromagnetic forces acting at a magnetic coil 101 energized below the predefined current threshold value. This radio tion of holding the armature plunger assembly in its rest position is taken from the holding device 110.

FIGS. 9 and 10 schematically show a third exemplary embodiment of the tripping device 100 according to the invention in two different switching states. 9 shows the triggering device 100 again in the "ready to trigger" state, the armature plunger assembly is correspondingly in its rest position The retaining device 110 is positively connected to the armature 102 via the two coupling elements 114 formed as latching nubs at the free ends of the spring legs 111 Figure 10 shows the triggering device 100 again in the "triggered" state, the armature plunger assembly is accordingly in its tripped position. The holding device 110 is accordingly no longer positively coupled to the armature 102. The armature plunger assembly is fully released, i. the holding device 110 is decoupled from the armature 102 and at this time exerts no more force on the armature plunger assembly, which would force these back into their rest position.

The rear part device for returning the armature plunger assembly to its rest position is in turn formed as Rückstellhe- at 121, as it is already known from the first embodiment shown in Figures 1 to 6. In contrast to this first exemplary embodiment, the triggering device 100 of the third exemplary embodiment illustrated in FIGS. 9 and 10 has an additional mechanical force accumulator in the form of a compression spring 106 which is supported against the housing 2 and applies an additional force to the armature plunger. Assembly exercises.

If the electric current flowing through the magnet coil 101 now exceeds the predefined current threshold value-for example because of a short circuit-then the armature plunger assembly becomes extinct owing to the high magnetic forces moved in its rest position in the direction of its tripping position. Due to the high magnetic forces as well as the force exerted by the compression spring 106 on the armature 102, the spring-loaded positive connection between the armature 102 and the holding device 110 is achieved. In the further course accelerates the

Compression spring 106, the armature plunger assembly additionally in the direction of its tripped position. Since the movement of the armature plunger assembly is supported by the compression spring 106 during this entire release movement, the movement is faster, the pulse to the switching contact 6 is increased. This can be opened faster. The switching mechanism is triggered earlier, so that the short-circuit current can not rise so much. As a result, the protective switching device 1 is thermally less stressed, as a result of which smaller I ² t values and a higher switching capacity are achieved.

The compression spring 106 may, as shown in Figures 9 and 10, be formed as a helical spring. The use of other spring designs, such as disc springs, however, is also possible.

FIGS. 11 to 15 schematically show further embodiments of the holding device 110. The holding device 110 shown in FIGS. 11 and 12 likewise has a U-shaped main body with two spring legs 111 and a connecting region 112 connecting the two spring legs 111. In contrast to the exemplary embodiments illustrated in FIGS. 1 to 10, however, the holding device 110 is rotated by 90 ° in this embodiment so that the connecting region 112 is not arranged behind, but next to, the armature 102 in a longitudinal extension direction of the armature plunger assembly is. It should be noted that the distal end of the armature 102, on which the coupling point (s) 104 are arranged, protrudes from the magnetic coil 101 in the rest position, in order to enable a coupling with the holding device 110. If necessary, how shown in Figure 11, the body of the armature 102 for this purpose to extend accordingly. However, the basic mode of operation of such a holding device 110 rotated by 90 ° corresponds to the mode of operation of the holding device 110 realized in the above-described exemplary embodiments.

Another possibility for constructive design of the holding device 110 is the use of an annular spring 116, see Figure 13. In this case, the arranged at the distal end of the armature 102 coupling point 104 is advantageously designed as a circumferential annular groove in which the annular spring completely, or as shown in Figure 13 - intermittently positively engages to hold the armature plunger assembly in its rest position. The setting of the maximum holding force of the annular spring 116 designed as holding device 100 can be done both on the spring stiffness of the annular spring 116 and on the section length of those areas of the annular spring 116, which form the form-fitting with the trained as an annular groove coupling point 104.

Another possibility for constructive design of the holding device 110 is shown schematically in FIGS. 14 and 15. Instead of a U-shaped holding element, the holding device 110 is formed by a spring-loaded detent ball 117. The detent ball 117 is pressed in the rest position of the armature plunger assembly by means of a detent spring 118 which is supported via the housing 2 in the form of locking groove formed coupling point 104 of the armature 102 to this - and thus the armature plunger Assembly - to be kept in the rest position at electrical currents below the predefined current threshold. On the one hand, detent springs 118 of different spring hardness can be used to set the maximum holding force. On the other hand, the use of several such spring-loaded detent balls 117 is possible. In addition, the maximum holding power can also be due a change in the cross-sectional geometry of the locking groove formed as a coupling point 104 are changed to facilitate sliding out of the detent ball 117 from its associated coupling point 104 or complicate.

The embodiments of the holding device 110 illustrated in FIGS. 11 to 15 can be combined with individual elements of the exemplary embodiments illustrated in FIGS. 1 to 10, for example the use of a restoring spring 122 or an additional compression spring 106, and thus not in FIGS 15 combinations shown limited.

LIST OF REFERENCE NUMBERS

1 protective device

2 housings

3 actuator

4 fixed contact

5 moving contact

6 switching contact

7 coupling bracket

8 moving contact carrier

9 input terminal

10 output terminal

11 front

12 mounting side

13 strand

14 Arc quenching chamber

15 plate

16 contact horn

17 Guardrail

18 antechamber area

19 release lever

20 bimetallic element

21 reset contour

22 yoke

100 triggering device

101 solenoid

102 anchors

103 pestles

104 coupling point

105 chamfer

106 compression spring

110 holding device

111 spring legs

112 connecting bridge

113 Adjusting screw Coupling element stranded wire

Ring spring detent ball spring reset lever return spring

Claims

claims

Tripping device (100) for an electromechanical protective switching device (1), in particular a circuit breaker or circuit breaker, with

a magnetic coil (101),

- an armature plunger assembly comprising an armature (102) and a plunger (103) which is movable by means of the magnetic coil (101) relative thereto from a rest position to a released position,

- A holding device (110) which is coupled to the armature (102) and acts thereon to keep it at electrical currents below a predefined current threshold in its rest position,

characterized ,

the holding device (110) is designed such that the armature (102) is completely released when the predefined current threshold value is exceeded.

Tripping device (100) according to claim 1,

characterized ,

in that the armature (102) has at its at least one coupling point (104) at its distal end, which cooperates with a coupling element (114) of the holding device (110) to form a mechanical coupling.

Tripping device (100) according to claim 2,

characterized ,

in that the coupling point (104) is designed as a latching groove and the coupling element (114) as a resilient latching element which engages in the latching groove in the rest position

4. triggering device (100) according to claim 3,

characterized , that the latching element is designed as a leaf spring, whose one free end engages in the rest position in the latching groove.

Tripping device (100) according to claim 3,

characterized ,

that the latching element is designed as an annular spring (116) which engages in the rest position in the latching groove.

Tripping device (100) according to claim 3,

characterized ,

the latching element is designed as a U-shaped bent spring element (111, 112), the two free ends of which engage in the rest position in the latching groove.

Tripping device (100) according to claim 3,

characterized ,

that the latching element is designed as a spring-loaded latching ball (117) which is pressed in the rest position into the latching groove.

Tripping device (100) according to claim 1,

characterized ,

in that the armature (102) has a chamfer (105) in the region of its distal end.

Tripping device (100) according to one of the preceding claims, characterized

that the triggering device (100) is a mechanical

Adjusting element has to adjust the triggering device (100) to the predefined current threshold.

Tripping device (100) according to claim 9 in conjunction with one of claims 2 to 8,

characterized ,

in that the adjusting element is designed as an adjusting screw (113), such that upon actuation of the adjusting screw (113) the position of the coupling element (114) is variable.

11. Tripping device (100) according to one of the preceding claims, characterized in that

the triggering device (100) has a mechanical force accumulator (106) which urges the armature plunger assembly in the direction of its released position when the predefined current threshold value is exceeded.

Tripping device (100) according to one of the preceding claims, characterized

in that the triggering device (100) has a resetting device (121, 122) which is designed to return the armature plunger assembly to its rest position after falling below the predefined current threshold value. 13. triggering device (100) according to claim 12,

characterized ,

in that the rear-part device has a mechanical energy store (122) which urges the armature-tappet assembly from its released position into its rest position.

Tripping device (100) according to one of Claims 12 or 13, characterized

in that the rear part device has a reset lever (121) which can be mechanically coupled to a switching mechanism of the protective switching device (1) so that the armature plunger assembly can be returned to its rest position by means of the reset lever (121) coupled to the switching mechanism.

15. Tripping device (100) according to one of the preceding claims, characterized in that in that the holding device (110) is formed from a bimetallic strip or a shape-memory material.

Electromechanical circuit breaker (1), for example, circuit breaker or circuit breaker, which has a tripping device (100) according to one of claims 1 to 15.