EP0143927B1 - Device for returning the contact carrier of an electromagnetic switching device, especially of a protective circuit breaker - Google Patents

Device for returning the contact carrier of an electromagnetic switching device, especially of a protective circuit breaker Download PDF

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Publication number
EP0143927B1
EP0143927B1 EP84111280A EP84111280A EP0143927B1 EP 0143927 B1 EP0143927 B1 EP 0143927B1 EP 84111280 A EP84111280 A EP 84111280A EP 84111280 A EP84111280 A EP 84111280A EP 0143927 B1 EP0143927 B1 EP 0143927B1
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EP
European Patent Office
Prior art keywords
clapper
contact carrier
lever
type armature
restoring spring
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP84111280A
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German (de)
French (fr)
Other versions
EP0143927A2 (en
EP0143927A3 (en
Inventor
Georgi Cwetanski
Roland Kupferschmitt
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ASEA BROWN BOVERI AKTIENGESELLSCHAFT
Original Assignee
ASEA BROWN BOVERI AG
Asea Brown Boveri AG Germany
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Priority to AT84111280T priority Critical patent/ATE66091T1/en
Publication of EP0143927A2 publication Critical patent/EP0143927A2/en
Publication of EP0143927A3 publication Critical patent/EP0143927A3/en
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Publication of EP0143927B1 publication Critical patent/EP0143927B1/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00—Details of electromagnetic relays
    • H01H50/64—Driving arrangements between movable part of magnetic circuit and contact
    • H01H50/643—Driving arrangements between movable part of magnetic circuit and contact intermediate part performing a rotating or pivoting movement
    • H01H50/644—Driving arrangements between movable part of magnetic circuit and contact intermediate part performing a rotating or pivoting movement having more than one rotating or pivoting part
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00—Details of electromagnetic relays
    • H01H50/16—Magnetic circuit arrangements
    • H01H50/18—Movable parts of magnetic circuits, e.g. armature
    • H01H50/24—Parts rotatable or rockable outside coil

Definitions

  • the invention relates to a device according to the preamble of claim 1.
  • Known, commercially available contactors have an electromagnet system, the magnet armature of which is usually designed as a linearly movable component composed of a layered sheet metal work, which is moved or pressed under the force of compression springs, preferably two in number, from the attracted position into the dropped position.
  • a contact carrier to which the movement of the magnet armature is transmitted, is connected to the magnet armature.
  • a device of the type mentioned in which the hinged anchor is mounted in a knife-edge bearing, which has a cutting edge on the hinged anchor and an approximately U-shaped component fastened by the yoke and a yoke is formed.
  • the U-shaped component comprises part of the hinged anchor and between the free leg of the component and an extension attached to the hinged anchor there is a return spring which continuously urges the hinged anchor in the opening direction and at the same time presses it into its cutting edge bearing.
  • the object of the invention is to provide a device of the type mentioned, in which the hinged armature is pressed into the open position by the return spring, the magnetic force required in the device being reduced.
  • the hinged anchor has a cutting edge which engages in the corner formed by the yoke and the wall, which lie tightly against a wall of the housing and thus forms the pivot bearing of the hinged anchor. It is thanks to the return spring that the cutting edge is pressed into this corner.
  • an extension projecting from its pivot bearing is attached to it, which engages in a groove on the housing and thus guides the hinged anchor laterally.
  • a guide element on which the extension is molded is preferably fastened on the surface facing away from the magnetic core.
  • This connecting rod preferably encloses a holding crossbar attached to the contact carrier.
  • This holding crossmember can, for example, be fastened to the contact carrier in a snap-on manner.
  • a convex, approximately circular arc-shaped rolling surface is formed on the lever, the convex side of which is pressed against a pressure surface on the contact carrier and, when the hinged armature and thus also the lever, rolls on the pressure surface on the contact carrier.
  • the pressure surface is preferably formed on the crossmember.
  • the return spring does not execute a linear movement in its own axis, but rather a swiveling movement.
  • the direction of force changes with respect to the hinged armature on one side and to the contact carrier on the other side, so that the restoring force acting on the contact carrier can follow a sine function, whereby savings can additionally be made in the magnet system.
  • the restoring force from one position of the contact carrier to the other position does not correspond to the normal spring characteristic, but rather to the modified spring characteristic, the required force which must be brought about by the magnet system can be reduced. This also makes it possible to use a smaller and therefore less expensive magnet system.
  • the return spring is preferably performed according to the characterizing part of claim 9, whereby buckling of the return spring is prevented (see also DE-OS 33 35 712).
  • the electromagnetic switching device has a lower housing part 10 and an upper housing part 11 connected to it.
  • the lower housing part 10 essentially accommodates the magnet armature system 12, which consists of an L-shaped magnetic yoke 13, a magnetic core 14 and a hinged anchor 15 is formed.
  • the magnetic core 14 is surrounded by a coil 16, which is only indicated schematically in FIG. 1.
  • the hinged armature 15 overlaps both the free yoke surface 18 of the yoke leg 17, which is aligned parallel to the magnetic core 14.
  • the yoke surface 18 forms a corner 20 with the inner wall 19 of the lower housing part 10, into which a cutting edge 21 of the hinged armature 15 is pressed.
  • the corner 20 is the fulcrum of the hinged anchor 15.
  • a guide element 22 is fastened, which has an extension 23 which projects beyond the cutting edge 21 into a groove 24 in the lower housing part 10 and thus ensures a lateral fixation of the hinged anchor 15.
  • the guide element 22 has an eyelet 25 which is penetrated by a connecting rod 26, so that the connecting rod 26 is articulated on the eyelet 25.
  • the guide element 22 also has a cutting edge 27 approximately in its center.
  • the mechanism for resetting the hinged armature has a knee-shaped lever 28 (see FIG. 2), which has a spherical thickening 30 at the free end of its arm 29, with which it rests in a corner 31 on the upper housing part 11, so that a bearing is formed there is, so that a rotation of the lever 28 (also called toggle lever 28) in the bearing 30/31 is possible, but not a shift up or right.
  • the other arm 32 of the toggle lever 28 is shown in more detail in FIG. 2.
  • the arm 32 On the one hand, it has on its inside two horns 34 and 33 which are spaced apart from one another and between them a convex surface 35 which runs in the form of a circular arc and with which the arm 32 against a crossbar 36 on a contact carrier 37 (see FIG. 1) of the contactor is present.
  • the arm 32 On the outside, that is to say the side facing the folding anchor, the arm 32 on the other hand has a wedge-shaped nose 39. This nose 39 is located essentially exactly opposite the nose 27 on the guide element 22.
  • a return spring 40 is engaged between the nose 39 and the nose 27 and is held by a spring guide element 41.
  • the spring guide element is bent in a U-shape and has at the free leg ends support plates 42 and 43 which have nubs 44 on the opposite sides, which serve to guide the helical compression spring 40.
  • the support plates 42 On their outer surfaces, the support plates 42 have V-shaped depressions 45 and 46 which interact with the lugs 27 and 39. It has been found that such a U-shaped spring guide element prevents the spring 40 from buckling when actuated. This is attributable to the fact that on the one hand the free movement of the two support plates 42 and 43 is made possible, but because of the bracket 41, simultaneous pivoting of the two support plates is prevented.
  • the connecting lever 26 has an opening 50 through which the cross member 36 extends so that the folding armature is connected to the contact carrier via the connecting lever or the connecting rod 26.
  • the system formed from the hinged anchor 15, the spring 40 and the toggle lever 28 has a dead center position which is defined by the connecting line TT of the pivot point of the hinged anchor and the pivot point of the toggle lever 28.
  • the lever arrangement is designed so that it generally does not exceed its dead center position TT.
  • FIG. 3 shows the arrangement according to FIG. 1 in the tightened state.
  • the hinged anchor 15 is located in the vicinity of the magnetic yoke or the core 14 and at a slight distance a from it, so that the hinged anchor does not stick.
  • the spring 40 is compressed, due to the arrangement of the nose 39 in relation to the thickening 30 and thus the support of the toggle lever 28; by pivoting the lever elements, the distance between the two lugs 27 and 39 has decreased.
  • the lever arrangement is still above the connecting line T-T, which represents the dead center position.
  • the spring 40 has not only been compressed during the movement of the lever system, but it has also pivoted at an angle in its direction of force with respect to the pivot point T and the direction of movement of the contact carrier 37.
  • the force components of the support force of the folding anchor and that component which runs in the direction of movement of the contact carrier have changed in accordance with a sine function when pivoting the spring 40. This can be explained with reference to FIG. 4.
  • a graphical representation of the required or necessary contact force or restoring force K over the actuation path S can be seen.
  • Curve A is the force demand curve of a normal contactor, in which the restoring spring is only compressed linearly.
  • the curve has an area A1 in which only the return springs are compressed, and starting from the "contacts open" position, which corresponds to the dropped state of the magnet system. After a certain distance, the contacts close, so that at S s the curve A jumps from the area A1 to the area A2, the slope A2 representing a curve which corresponds to the coupled spring elasticity of the return spring and the contact force springs.
  • the curve M A indicates the magnetic force to be achieved with the magnet system; in any case, it must always be greater than the contact forces in order to always be able to overcome the forces which result from the return spring or the return springs and the contact force springs. Accordingly, curve M A is always above curve A.
  • curve A changes to curve B; the sine function when swiveling the spring results in a curve that slopes slightly in the direction of "closing the contacts".
  • Any desired curve or curve curve B can of course be achieved by means of a suitable geometric design. On the one hand, you can achieve an even stronger drop; you can achieve an almost constant curve B or you can approximate the curve of the force curve A. It has proven to be optimal to design curve B so that it drops slightly in the direction of the closing movement.
  • the curve B is then clearly below the area A 1, specifically by the amount E in the point S s . Accordingly, the area A2 shifts downward by the amount E, although the curve B2 is not parallel to the area A2 and also not parallel to the curve B in the area to the left of the point of contact closure.
  • the actual magnetic force demand curve generated in this way is the curve M B , which is clearly below the curve M A , from which it can be seen that the magnet system can be designed to be weaker than that of commercially available arrangements.
  • the contact point of the lever 28 on the cross member 36 is, as mentioned above, designed as an arcuate surface 35. As a result, there is more rolling of the surface 35 on the cross member 36 when the lever 28 is pivoted than a displacement, so that the frictional force between the cross member 36 and the rolling surface 35 is also reduced, as a result of which the force requirement of the magnet system can be reduced even further.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Electromagnets (AREA)
  • Switch Cases, Indication, And Locking (AREA)
  • Breakers (AREA)
  • Control Of Vehicles With Linear Motors And Vehicles That Are Magnetically Levitated (AREA)
  • Relay Circuits (AREA)
  • Mechanisms For Operating Contacts (AREA)

Abstract

An electromagnetic switching device has a magnet system with a hinged armature (15) which is connected to the contact carrier (37) via a connecting rod (26). A restoring spring arrangement is furthermore provided which presses the hinged armature (15) and thus the contact carrier back into an original position. In general, the contacts of the switching device are open when the magnet system is energised, and are closed in the unenergised state. The restoring spring arrangement is required to close them again. To simplify the design, the restoring spring arrangement is constructed as a restoring helical compression spring (40) which is supported on the one side on the hinged armature (15) and on the other side on a lever (28) which is mounted in a hinged manner on the housing (11), and which also abuts against the contact carrier (37). The drive train, which consists of the hinged armature (15), the restoring spring (40) and the lever (28), is always located outside the connecting line (T-T), which forms a dead-point line and connects the axis of rotation of the hinged armature (15) and the supporting axle of the lever (28) on the housing, so that a single helical compression spring ensures both the support of the hinged armature and the restoration of the contact carrier.

Description

Die Erfindung betrifft eine Einrichtung nach dem Oberbegriff des Anspruches 1.The invention relates to a device according to the preamble of claim 1.

Bekannte, handelsübliche Schütze besitzen ein Elektromagnetsystem, dessen Magnetanker meist als linear bewegbares, aus geschichtetem Blechwerk zusammengesetzes Bauteil ausgebildet ist, der unter der Kraft von Druckfedern, vorzugsweise zwei an der Zahl, aus der angezogenen Lage in die abgefallene Lage bewegt bzw. gedrückt wird. Mit dem Magnetanker verbunden ist ein Kontaktträger, auf den die Bewegung des Magnetankers übertragen wird.Known, commercially available contactors have an electromagnet system, the magnet armature of which is usually designed as a linearly movable component composed of a layered sheet metal work, which is moved or pressed under the force of compression springs, preferably two in number, from the attracted position into the dropped position. A contact carrier, to which the movement of the magnet armature is transmitted, is connected to the magnet armature.

Elektrische Schaltgeräte, deren Elektromagnetsystem ein Klappankersystem ist, sind bei Schützen nur in sehr geringem Umfang bekanntgeworden. Ein wesentliches Problem besteht nämlich darin, den doch relativ großen Klappanker an dem meist L-förmigen Magnetjoch drehbar aufzulagern, wobei es auch Probleme gibt, die Rückstellfeder für den Klappanker mit letzterem zu verbinden. Demgemäß sind wenigstens zwei Federn erforderlich, nämlich eine Feder, die den Klappanker in seine Drehachse, d. h. also in ein Schneidenlager hineindrückt, und eine andere Feder, die als Rückstellfeder eingesetzt ist. In jedem Falle benötigt man zwei und unter Umständen auch mehr Federn.Electrical switching devices, the electromagnet system of which is a hinged armature system, have only become known to a very limited extent in contactors. A major problem is namely that the relatively large hinged armature is rotatably supported on the mostly L-shaped magnetic yoke, and there are also problems in connecting the return spring for the hinged armature with the latter. Accordingly, at least two springs are required, namely a spring that the hinged anchor in its axis of rotation, i. H. So pushes into a cutting edge bearing, and another spring that is used as a return spring. In any case you need two and possibly more springs.

Aus der US-A 2 432 899 ist eine Einrichtung der eingangs genannten Art bekannt geworden, bei der der Klappanker in einem Schneidenlager gelagert ist, welches durch eine Schneide am Klappanker und eine durch das Joch und ein am Joch befestigtes, etwa U-förmiges Bauelement gebildet ist. Das U-förmige Bauelement umfaßt einen Teil des Klappankers und zwischen dem freien Schenkel des Bauelementes und einem am Klappanker befestigten Fortsatz befindet sich eine Rückstellfeder, die den Klappanker dauernd in Öffnungsrichtung beaufschlagt und ihn gleichzeitig auch in sein Schneidenlager drückt.From US-A 2 432 899 a device of the type mentioned is known, in which the hinged anchor is mounted in a knife-edge bearing, which has a cutting edge on the hinged anchor and an approximately U-shaped component fastened by the yoke and a yoke is formed. The U-shaped component comprises part of the hinged anchor and between the free leg of the component and an extension attached to the hinged anchor there is a return spring which continuously urges the hinged anchor in the opening direction and at the same time presses it into its cutting edge bearing.

Aufgabe der Erfindung ist es, eine Einrichtung der eingangs genannten Art zu schaffen, bei der der Klappanker durch die Rückstellfeder in die geöffnete Stellung gedrückt ist, wobei die bei der Einrichtung erforderliche Magnetkraft reduziert ist.The object of the invention is to provide a device of the type mentioned, in which the hinged armature is pressed into the open position by the return spring, the magnetic force required in the device being reduced.

Diese Aufgabe wird erfindungsgemäß gelöst durch die Merkmale des Anspruches 1.This object is achieved according to the invention by the features of claim 1.

In zweckmäßiger Ausgestaltung weist der Klappanker eine Schneide auf, die in die durch das an einer Wand des Gehäuses dicht anliegende Joch und die Wand gebildete und so das Drehlager des Klappankers bildende Ecke eingreift. Daß die Schneide in diese Ecke hineingedrückt wird, ist der Rückstellfeder zu verdanken.In an expedient embodiment, the hinged anchor has a cutting edge which engages in the corner formed by the yoke and the wall, which lie tightly against a wall of the housing and thus forms the pivot bearing of the hinged anchor. It is thanks to the return spring that the cutting edge is pressed into this corner.

Zur Führung des Klappankers ist an diesen ein sein Drehlager überragender Fortsatz angebracht, der in eine Nut am Gehäuse eingreift und so den Klappanker seitlich führt.To guide the hinged anchor, an extension projecting from its pivot bearing is attached to it, which engages in a groove on the housing and thus guides the hinged anchor laterally.

In weiterer Ausgestaltung der Erfindung ist in bevorzugter Weise auf der dem Magnetkern abgewandten Fläche ein Führungselement befestigt, an dem der Fortsatz angeformt ist.In a further embodiment of the invention, a guide element on which the extension is molded is preferably fastened on the surface facing away from the magnetic core.

Am Führungselement ist weiterhin eine Öse angeformt, an der die Verbindungsstange angelenkt ist. Diese Verbindungsstange umschließt in bevorzugter Weise eine am Kontaktträger angebrachte Haltetraverse. Diese Haltetraverse kann beispielsweise schnappbar an den Kontaktträger befestigt sein.An eyelet is also formed on the guide element, to which the connecting rod is articulated. This connecting rod preferably encloses a holding crossbar attached to the contact carrier. This holding crossmember can, for example, be fastened to the contact carrier in a snap-on manner.

Die Kraftübertragung von der Rückstellfeder auf den Kontaktträger erfolgt über eine Übertragungsfläche am Hebel. Demgemäß ist am Hebel eine konvexe, annähernd kreisbogenförmige Wälzfläche angeformt, deren konvexe Seite gegen eine Druckfläche am Kontaktträger angedrückt ist und bei Bewegung des Klappankers und damit auch des Hebels sich an der Druckfläche am Kontaktträger abwälzt.Power is transferred from the return spring to the contact carrier via a transmission surface on the lever. Accordingly, a convex, approximately circular arc-shaped rolling surface is formed on the lever, the convex side of which is pressed against a pressure surface on the contact carrier and, when the hinged armature and thus also the lever, rolls on the pressure surface on the contact carrier.

In bevorzugter Weise ist die Druckfläche dabei an der Traverse gebildet.The pressure surface is preferably formed on the crossmember.

Aufgrund der erfindungsgemäßen Ausgestaltung führt die Rückstellfeder keine lineare Bewegung in ihrer eigenen Achse aus, sondern eine Schwenkbewegung. Dadurch verändert sich die Kraftrichtung bezogen auf den Klappanker auf der einen Seite und auf den Kontaktträger auf der anderen Seite, so daß die auf den Kontaktträger wirkende Rückstellkraft einer Sinusfunktion folgen kann, wodurch zusätzlich noch Einsparungen am Magnetsystem getroffen werden können. Dadurch, daß die Rückstellkraft aus der einen Stellung des Kontaktträgers in die andere Stellung nicht der normalen Federkennlinie entspricht, sondern der modifizierten Federkennlinie, kann der erforderliche Kraftaufwand, der mit dem Magnetsystem bewirkt werden muß, reduziert werden. Dadurch besteht auch die Möglichkeit, ein kleineres und damit preisgünstigeres Magnetsystem zu verwenden.Because of the configuration according to the invention, the return spring does not execute a linear movement in its own axis, but rather a swiveling movement. As a result, the direction of force changes with respect to the hinged armature on one side and to the contact carrier on the other side, so that the restoring force acting on the contact carrier can follow a sine function, whereby savings can additionally be made in the magnet system. Because the restoring force from one position of the contact carrier to the other position does not correspond to the normal spring characteristic, but rather to the modified spring characteristic, the required force which must be brought about by the magnet system can be reduced. This also makes it possible to use a smaller and therefore less expensive magnet system.

Die Rückstellfeder ist vorzugsweise gemäß kennzeichnendem Teil des Anspruches 9 geführt, wodurch ein Ausknicken der Rückstellfeder verhindert ist (siehe auch DE-OS 33 35 712).The return spring is preferably performed according to the characterizing part of claim 9, whereby buckling of the return spring is prevented (see also DE-OS 33 35 712).

Anhand der Zeichnung, in der ein Ausführungsbeispiel der Erfindung dargestellt ist, soll die Erfindung näher erläutert und beschrieben werden.The invention will be explained and described in more detail with reference to the drawing, in which an embodiment of the invention is shown.

Es zeigen:

Figur 1
eine schematische Darstellung eines erfindungsgemäßen elektromagnetischen Schaltgerätes,
Figur 2
eine Einzelheit aus dem Gerät gemäß Figur 1,
Figur 3
eine andere Stellung des Schaltgerätes der Figur 1 und
Figur 4
eine Kraft-Wegkurve für das Schaltgerät gemäß Figur 1.
Show it:
Figure 1
1 shows a schematic illustration of an electromagnetic switching device according to the invention,
Figure 2
a detail from the device of Figure 1,
Figure 3
another position of the switching device of Figure 1 and
Figure 4
a force-displacement curve for the switching device according to Figure 1.

Das elektromagnetische Schaltgerät gemäß Figur 1 besitzt ein Gehäuseunterteil 10 und ein mit diesem verbundenes Gehäuseoberteil 11. Das Gehäuseunterteil 10 nimmt im wesentlichen das Magnetankersystem 12 auf, das aus einem in nicht weiter dargestellter Weise am Gehäuseunterteil befestigten L-förmigen Magnetjoch 13, einem Magnetkern 14 und einem Klappanker 15 gebildet ist. Der Magnetkern 14 wird von einer Spule 16 umgeben, die in der Figur 1 nur schematisch angedeutet ist.The electromagnetic switching device according to FIG. 1 has a lower housing part 10 and an upper housing part 11 connected to it. The lower housing part 10 essentially accommodates the magnet armature system 12, which consists of an L-shaped magnetic yoke 13, a magnetic core 14 and a hinged anchor 15 is formed. The magnetic core 14 is surrounded by a coil 16, which is only indicated schematically in FIG. 1.

Der Klappanker 15 übergreift sowohl die freie Jochfläche 18 des Jochschenkels 17, der parallel zu dem Magnetkern 14 ausgerichtet ist. Die Jochfläche 18 bildet mit der Innenwandung 19 des Gehäuseunterteils 10 eine Ecke 20, in die eine Schneidekante 21 des Klappankers 15 hineingedrückt wird. Die Ecke 20 ist der Drehpunkt des Klappankers 15.The hinged armature 15 overlaps both the free yoke surface 18 of the yoke leg 17, which is aligned parallel to the magnetic core 14. The yoke surface 18 forms a corner 20 with the inner wall 19 of the lower housing part 10, into which a cutting edge 21 of the hinged armature 15 is pressed. The corner 20 is the fulcrum of the hinged anchor 15.

Auf der oberen Fläche des Klappankers 15 ist ein Führungselement 22 befestigt, das einen Fortsatz 23 besitzt, der über die Schneidekante 21 hinausragt in eine Nut 24 im Gehäuseunterteils 10 und so für eine seitliche Fixierung des Klappankers 15 sorgt. Das Führungselement 22 besitzt eine Öse 25, die von einer Verbindungsstange 26 durchgriffen ist, so daß die Verbindungsstange 26 an der Öse 25 gelenkig angehängt ist.On the upper surface of the hinged anchor 15, a guide element 22 is fastened, which has an extension 23 which projects beyond the cutting edge 21 into a groove 24 in the lower housing part 10 and thus ensures a lateral fixation of the hinged anchor 15. The guide element 22 has an eyelet 25 which is penetrated by a connecting rod 26, so that the connecting rod 26 is articulated on the eyelet 25.

Das Führungselement 22 besitzt ferner annähernd in seiner Mitte eine Schneide 27.The guide element 22 also has a cutting edge 27 approximately in its center.

Der Mechanismus für die Rückstellung des Klappankers besitzt einen knieförmigen Hebel 28 (siehe Fig. 2), der am freien Ende seines Armes 29 eine kugelförmige Verdickung 30 aufweist, mit der er in einer Ecke 31 am Gehäuseoberteil 11 anliegt, so daß dort ein Lager gebildet ist, und zwar so, daß eine Verdrehung des Hebels 28 (auch Kniehebel 28 genannt) im Lager 30/31 möglich ist, nicht aber eine Verschiebung nach oben oder rechts. Der andere Arm 32 des Kniehebels 28 ist in der Fig. 2 näher dargestellt. Er besitzt einerseits auf seiner Innenseite zwei in Abstand zueinander liegende Hörner 34 und 33 und dazwischen eine kreisbogenartig verlaufende, konvexe Fläche 35, mit der der Arm 32 gegen eine Traverse 36 an einem Kontaktträger 37 (siehe Fig. 1) des Schützes anliegt. Auf der Außenseite, also der dem Klappanker zugewandten Seite besitzt der Arm 32 andererseits eine keilförmige Nase 39. Diese Nase 39 befindet sich im wesentlichen genau der Nase 27 am Führungselement 22 gegenüber. Zwischen der Nase 39 und der Nase 27 ist eine Rückstellfeder 40 eingeschaltet, die von einem Federführungselement 41 gehalten ist. Das Federführungselement ist U-förmig gebogen und weist an den freien Schenkelenden Auflageplättchen 42 und 43 auf, die an den sich gegenüberliegenden Seiten Noppen 44 besitzen, die zur Führung der Schraubendruckfeder 40 dienen. Auf ihren Außenflächen besitzen die Auflageplättchen 42 V-förmige Vertiefungen 45 und 46, die mit den Nasen 27 und 39 zusammenwirken. Es hat sich herausgestellt, daß ein derartiges U-förmiges Federführungselement ein Ausknicken der Feder 40 bei der Betätigung verhindert. Dies dabei zurückzuführen, daß auf der einen Seite die freie Beweglichkeit der beiden Auflageplättchen 42 und 43 ermöglicht ist, daß aber aufgrund des Bügels 41 ein gleichzeitiges Verschwenken der beiden Auflageplättchen verhindert ist.The mechanism for resetting the hinged armature has a knee-shaped lever 28 (see FIG. 2), which has a spherical thickening 30 at the free end of its arm 29, with which it rests in a corner 31 on the upper housing part 11, so that a bearing is formed there is, so that a rotation of the lever 28 (also called toggle lever 28) in the bearing 30/31 is possible, but not a shift up or right. The other arm 32 of the toggle lever 28 is shown in more detail in FIG. 2. On the one hand, it has on its inside two horns 34 and 33 which are spaced apart from one another and between them a convex surface 35 which runs in the form of a circular arc and with which the arm 32 against a crossbar 36 on a contact carrier 37 (see FIG. 1) of the contactor is present. On the outside, that is to say the side facing the folding anchor, the arm 32 on the other hand has a wedge-shaped nose 39. This nose 39 is located essentially exactly opposite the nose 27 on the guide element 22. A return spring 40 is engaged between the nose 39 and the nose 27 and is held by a spring guide element 41. The spring guide element is bent in a U-shape and has at the free leg ends support plates 42 and 43 which have nubs 44 on the opposite sides, which serve to guide the helical compression spring 40. On their outer surfaces, the support plates 42 have V-shaped depressions 45 and 46 which interact with the lugs 27 and 39. It has been found that such a U-shaped spring guide element prevents the spring 40 from buckling when actuated. This is attributable to the fact that on the one hand the free movement of the two support plates 42 and 43 is made possible, but because of the bracket 41, simultaneous pivoting of the two support plates is prevented.

Der Verbindungshebel 26 besitzt einen Durchbruch 50, durch den die Traverse 36 hindurchgreift, so daß über den Verbindungshebel bzw. die Verbindungsstange 26 der Klappanker mit dem Kontaktträger verbunden ist.The connecting lever 26 has an opening 50 through which the cross member 36 extends so that the folding armature is connected to the contact carrier via the connecting lever or the connecting rod 26.

Das aus dem Klappanker 15, der Feder 40 und dem Kniehebel 28 gebildete System besitzt eine Totpunktlage, die durch die Verbindungslinie T-T des Drehpunktes des Klappankers und des Drehpunktes des Kniehebels 28 definiert wird. Die Hebelanordnung ist so ausgelegt, daß sie ihre Totpunktlage T-T grundsätzlich nicht überschreitet. Dadurch wird immer eine Kraftkomponente in Richtung des Drehlagers des Klappankers und in Richtung der Bewegung des Kontaktträgers in Schließrichtung erzeugt, so daß mittels der einen Feder 40 der Klappanker 15 sowohl an Ort und Stelle gehalten als auch zurückgestellt werden kann.The system formed from the hinged anchor 15, the spring 40 and the toggle lever 28 has a dead center position which is defined by the connecting line TT of the pivot point of the hinged anchor and the pivot point of the toggle lever 28. The lever arrangement is designed so that it generally does not exceed its dead center position TT. As a result, there is always a force component in the direction of the pivot bearing of the folding anchor and in the direction of the movement of the contact carrier generated in the closing direction, so that by means of the one spring 40 the hinged anchor 15 can both be held in place and reset.

Die Fig. 3 zeigt die Anordnung gemäß Fig. 1 in angezogenem Zustand. Der Klappanker 15 befindet sich in der Nähe des Magnetjoches bzw. des Kernes 14 und zwar in einem geringfügigen Abstand a hierzu, damit der Klappanker nicht klebt. Zusätzlich ist die Feder 40 zusammengedrückt, aufgrund der Anordnung der Nase 39 bezogen auf die Verdickung 30 und damit Auflagerung des Kniehebels 28; durch die Verschwenkung der Hebelelemente hat sich der Abstand zwischen den beiden Nasen 27 und 39 verringert. Die Hebelanordnung befindet sich dabei immer noch oberhalb der Verbindungslinie T-T, die die Totpunktlage darstellt.FIG. 3 shows the arrangement according to FIG. 1 in the tightened state. The hinged anchor 15 is located in the vicinity of the magnetic yoke or the core 14 and at a slight distance a from it, so that the hinged anchor does not stick. In addition, the spring 40 is compressed, due to the arrangement of the nose 39 in relation to the thickening 30 and thus the support of the toggle lever 28; by pivoting the lever elements, the distance between the two lugs 27 and 39 has decreased. The lever arrangement is still above the connecting line T-T, which represents the dead center position.

Die Feder 40 ist bei der Bewegung des Hebelsystems nicht nur zusammengedrückt worden, sondern sie hat sich auch in ihrer Kraftrichtung bezogen auf den Drehpunkt T und die Bewegungsrichtung des Kontaktträgers 37 winkelig verschwenkt. Die Kraftkomponenten der Auflagerkraft des Klappankers und derjenigen Komponente, die in Bewegungsrichtung des Kontaktträgers verläuft, haben sich entsprechend einer Sinusfunktion beim Verschwenken der Feder 40 geändert. Dies ist anhand der Fig. 4 zu erläutern. Man erkennt eine graphische Darstellung der erforderlichen bzw. notwendigen Kontaktkraft bzw. Rückstellkraft K über dem Betätigungsweg S. Die Kurve A ist die Kraftbedarfskurve eines normalen Schützes, bei dem die Rückstellfeder lediglich linear zusammengedrückt wird. Die Kurve besitzt einen Bereich A₁, in dem lediglich die Rückstellfedern zusammengedrückt werden, und zwar ausgehend von der Stellung "Kontakte offen", die dem abgefallenen Zustand des Magnetsystems entspricht. Nach einem gewissen Weg schließen die Kontakte, so daß bei Ss die Kurve A von dem Bereich A₁ sprunghaft übergeht in den Bereich A₂, wobei die Steigung A₂ eine Kurve darstellt, die der gekoppelten Federelastizität der Rückstellfeder und der Kontaktkraftfedern entspricht. Die Kurve MA deutet die mit dem Magnetsystem zu erzielende Magnetkraft an; sie muß in jedem Falle immer größer sein als die Kontaktkräfte, um die Kräfte, die von der Rückstellfeder bzw. den Rückstellfedern und den Kontaktkraftfedern herrühren, immer überwinden zu können. Demgemäß liegt die Kurve MA immer oberhalb der Kurve A.The spring 40 has not only been compressed during the movement of the lever system, but it has also pivoted at an angle in its direction of force with respect to the pivot point T and the direction of movement of the contact carrier 37. The force components of the support force of the folding anchor and that component which runs in the direction of movement of the contact carrier have changed in accordance with a sine function when pivoting the spring 40. This can be explained with reference to FIG. 4. A graphical representation of the required or necessary contact force or restoring force K over the actuation path S can be seen. Curve A is the force demand curve of a normal contactor, in which the restoring spring is only compressed linearly. The curve has an area A₁ in which only the return springs are compressed, and starting from the "contacts open" position, which corresponds to the dropped state of the magnet system. After a certain distance, the contacts close, so that at S s the curve A jumps from the area A₁ to the area A₂, the slope A₂ representing a curve which corresponds to the coupled spring elasticity of the return spring and the contact force springs. The curve M A indicates the magnetic force to be achieved with the magnet system; in any case, it must always be greater than the contact forces in order to always be able to overcome the forces which result from the return spring or the return springs and the contact force springs. Accordingly, curve M A is always above curve A.

Durch die erfindungsgemäße Ausgestaltung und Anordnung der Rückstellfeder 40 verändert sich die Kurve A in die Kurve B; durch die Sinus-Funktion beim Verschwenken der Feder erhält man eine leicht in Richtung "Schließen der Kontakte" abfallende Kurve. Durch geeignete geometrische Ausbildung kann natürlich jede gewünschte Kurve bzw. jeder gewünschte Kurvenverlauf B erzielt werden. Man kann zum einen ein noch stärkeres Abfallen erzielen; man kann eine annähernd konstante Kurve B erreichen oder man kann den Kurvenverlauf der Kraftkurve A annähern. Es hat sich als optimal herausgestellt, die Kurve B so zu gestalten, daß sie in Richtung der Schließbewegung leicht abfällt. Im Bereich Ss liegt dann die Kurve B deutlich unter dem Bereich A₁, und zwar um den Betrag E genau im Punkt Ss. Demgemäß verschiebt sich auch der Bereich A₂ um den Betrag E nach unten, wobei allerdings die Kurve B₂ nicht parallel zu dem Bereich A₂ und auch nicht parallel zu der Kurve B im Bereich links von der Stelle Kontaktschließen verläuft.Due to the design and arrangement of the return spring 40 according to the invention, curve A changes to curve B; the sine function when swiveling the spring results in a curve that slopes slightly in the direction of "closing the contacts". Any desired curve or curve curve B can of course be achieved by means of a suitable geometric design. On the one hand, you can achieve an even stronger drop; you can achieve an almost constant curve B or you can approximate the curve of the force curve A. It has proven to be optimal to design curve B so that it drops slightly in the direction of the closing movement. In the area S s , the curve B is then clearly below the area A 1, specifically by the amount E in the point S s . Accordingly, the area A₂ shifts downward by the amount E, although the curve B₂ is not parallel to the area A₂ and also not parallel to the curve B in the area to the left of the point of contact closure.

Die hierdurch erzeugte tatsächliche Magnetkraftbedarfskurve ist die die Kurve MB, die deutlich unterhalb der Kurve MA liegt, woraus ersichtlich ist, daß das Magnetsystem schwächer ausgebildet sein kann, als das handelsüblicher Anordnungen.The actual magnetic force demand curve generated in this way is the curve M B , which is clearly below the curve M A , from which it can be seen that the magnet system can be designed to be weaker than that of commercially available arrangements.

Die Auflagestelle des Hebels 28 an der Traverse 36 ist, wie oben erwähnt, als kreisbogenförmige Fläche 35 ausgebildet. Dadurch erfolgt mehr ein Abwälzen der Fläche 35 an der Traverse 36 beim Verschwenken des Hebels 28 als ein Verschieben, so daß die Reibungskraft zwischen der Traverse 36 und der Wälzfläche 35 ebenfalls verringert ist, wodurch der Kraftbedarf des Magnetsystems noch weiter verringert werden kann.The contact point of the lever 28 on the cross member 36 is, as mentioned above, designed as an arcuate surface 35. As a result, there is more rolling of the surface 35 on the cross member 36 when the lever 28 is pivoted than a displacement, so that the frictional force between the cross member 36 and the rolling surface 35 is also reduced, as a result of which the force requirement of the magnet system can be reduced even further.

Mit der erfindungsgemäßen Anordnung wird ein Hebelsystem vorgestellt, das keine Überschreitung einer Totpunktlage aufweist. Durch die erfindungsgemäße Ausgestaltung werden mehrere Federn eingespart, in dem lediglich eine einzige Feder für die Funktion Rückstellung und Erzeugung des Lagerdrucks erforderlich wird.With the arrangement according to the invention, a lever system is presented which does not exceed a dead center position. The configuration according to the invention saves a number of springs, in which only a single spring is required for the function to reset and generate the bearing pressure.

Claims (9)

  1. Device for resetting the contact carrier (37) of an electromagnetic switch gear, having a magnet system with clapper-type armature (15) which is connected to the contact carrier (37) via a connecting rod (26), and having a restoring spring which is supported on the one hand on the clapper-type armature (15) which presses the clapper-type armature which can rotate around a fixed pivot bearing and thus the contact carrier back into the initial position, such that a power component which presses the clapper-type armature (15) into its pivot bearing and a power component which acts in the closing direction of the contact carrier are continuously produced by the restoring spring (40), characterised in that the restoring spring (40) is supported on the other hand on a lever (28) which is mounted in an articulated manner on the housing (11) and rests against the contact carrier (37), and in that the clapper-type armature (15), which can be rotated about the pivot bearing (20, 21), the restoring spring (40) and the lever (28) form a train of gears and the connecting points of the restoring spring (40) on the clapper-type armature (15) and on the lever (28) lie permanently outside the connecting line (T-T) forming a dead-centre line, which connecting line connects the centre axis of the pivot bearing (20, 21) of the clapper-type armature (15) and the pivot point of the lever (28) on the housing.
  2. Device according to Claim 1, characterised in that the clapper-type armature (15) has a cutter (21) which engages in the corner formed by the yoke (13), resting tightly against a wall of the housing (10) and the wall and thus forming the pivot bearing of the clapper-type armature (15).
  3. Device according to Claim 2, characterised in that mounted on the clapper-type armature (15) is a prolongation (23) which projects beyond its pivot bearing and engages in a groove (24) on the housing and thus guides the clapper-type armature laterally.
  4. Device according to Claim 3, characterised in that fastened on the surface of the clapper-type armature (15) facing away from the magnet core (14) is a guide element (22) on which the prolongation (23) is formed.
  5. Device according to Claim 4, characterised in that formed onto the guide element (22) is a lug (25) to which the connecting rod (26) is coupled.
  6. Device according to one of the previous claims, characterised in that the connecting rod (26) encloses a retaining cross-member (36) mounted on the contact carrier (37).
  7. Device according to one of the previous claims, characterised in that formed onto the lever (28) is a convex, approximately circular arc-shaped rolling surface (35), the convex side of which is pressed against a pressure surface on the contact carrier and, when the clapper-type armature and thus also the lever (28) move, rolls against the pressure surface on the contact carrier (37).
  8. Device according to Claim 7, characterised in that the pressure surface is formed on the cross-member (36).
  9. Device according to one of the preceding claims, characterised in that the restoring spring (40) is guided on a spring guide element (41) which has two support plates, connected to one another, for the restoring spring, there being V-shaped grooves (45, 46) provided on the outer surface of the support plates, which grooves co-operate with noses (27, 39) formed onto the guide element (22) and onto the lever (28) in order to form two cutting bearings facing one another.
EP84111280A 1983-10-01 1984-09-21 Device for returning the contact carrier of an electromagnetic switching device, especially of a protective circuit breaker Expired - Lifetime EP0143927B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84111280T ATE66091T1 (en) 1983-10-01 1984-09-21 DEVICE FOR RESETTING THE CONTACT CARRIER OF AN ELECTROMAGNETIC SWITCHING DEVICE, ESPECIALLY A CONTACTOR.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3335732 1983-10-01
DE19833335732 DE3335732A1 (en) 1983-10-01 1983-10-01 DEVICE FOR RESETTING THE CONTACT CARRIER OF AN ELECTROMAGNETIC SWITCHGEAR, ESPECIALLY A CONTACTOR

Publications (3)

Publication Number Publication Date
EP0143927A2 EP0143927A2 (en) 1985-06-12
EP0143927A3 EP0143927A3 (en) 1987-08-19
EP0143927B1 true EP0143927B1 (en) 1991-08-07

Family

ID=6210709

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84111280A Expired - Lifetime EP0143927B1 (en) 1983-10-01 1984-09-21 Device for returning the contact carrier of an electromagnetic switching device, especially of a protective circuit breaker

Country Status (4)

Country Link
EP (1) EP0143927B1 (en)
JP (1) JPS60150533A (en)
AT (1) ATE66091T1 (en)
DE (2) DE3335732A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3335712A1 (en) * 1983-10-01 1985-04-11 Brown, Boveri & Cie Ag, 6800 Mannheim Holder for a compressively loadable helical spring
DE3644172A1 (en) * 1986-12-23 1988-07-07 Bbc Brown Boveri & Cie ELECTROMAGNETIC SWITCH DRIVE FOR AN ELECTRICAL SWITCHGEAR
GB2229038B (en) * 1989-03-07 1994-01-26 Matsushita Electric Works Ltd Electromagnetic contactor
CN111863533A (en) * 2020-08-06 2020-10-30 南京贝思特信息科技有限公司 Multifunctional contactor

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR553976A (en) * 1920-07-20 1923-06-02 Scintilla Ag Elastic armature of electromagnets for electric vibration regulators
US2432899A (en) * 1944-11-16 1947-12-16 Westinghouse Electric Corp Shockproof electromagnetic contactor
GB850641A (en) * 1955-10-20 1960-10-05 British Thomson Houston Co Ltd Improvements in and relating to electromagnetic contactors
DE1210080B (en) * 1959-03-25 1966-02-03 Licentia Gmbh Snap-action switch for economy switching of direct current magnets with switching parts arranged outside the magnet body
US3395259A (en) * 1965-06-16 1968-07-30 Smith Corp A O Electromagnetic contactor having improved knife-edge pivoted armature structure, insulating stop means and releasable arc shield
ES411949A1 (en) * 1973-02-15 1976-01-01 Llario Sole Some perfections in the manufacture of electromagnetic relays. (Machine-translation by Google Translate, not legally binding)
IT1059599B (en) * 1975-04-15 1982-06-21 Int Standard Electric Corp IMPROVED MINIATURE TYPE RELAY
DE2805424C2 (en) * 1978-02-09 1982-05-19 Schaltbau Gesellschaft mbH, 8000 München Electromagnetic contactor with hinged armature drive

Also Published As

Publication number Publication date
DE3484893D1 (en) 1991-09-12
EP0143927A2 (en) 1985-06-12
DE3335732C2 (en) 1988-09-22
DE3335732A1 (en) 1985-04-11
JPS60150533A (en) 1985-08-08
ATE66091T1 (en) 1991-08-15
EP0143927A3 (en) 1987-08-19

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