EP1376639B1 - Electromagnetic trip device with a linear plunger movement - Google Patents

Abstract

The electromagnetic switch has a hub surrounded by a half spiral driving coil. A fixed contact is placed near the magnetic gap. A plate unlocks the grip mechanism. The plate is moved and guided in translation along a magnetic yolk side, following a locking and unlocking path for an excess level input.

Description

The present invention relates to an electromagnetic release for electrical apparatus for example of the modular circuit breaker type, that is to say, in particular with a fixed contact cooperating with a contact which is mobile between two positions respectively against and remotely said fixed contact.

Said triggers are electromagnetic organs of disjunction which generally comprise a coil with a movable core associated with a striker to ensure, in case of overcurrent, the disjunction by opening the movable contact. In most configurations conventional, induction coils with mobile core with striker and return spring are mounted longitudinally in a cylinder head able to drive the magnetic flux.

There are also cross-section configurations in which the core and the coil develop transversely to the product. These configurations have the advantage of producing effects magnetic means favorable to the displacement of the movable contact on the one hand, and the arc generated at the spacing of the contacts on the other hand. So, in addition the purely mechanical effect of these triggers, which transform the magnetic energy to mechanically actuate a striker striking the moving contact in order to move it away from the fixed contact, these configurations generate magnetic field lines generating Laplace forces favorable to the propulsion of the contact moving towards the open position, especially when the intensity of the current exceeds a predetermined threshold and that the magnetic circuit is saturated.

The function of disjunction is thus doubly assured, by the mechanical effect and by the magnetic effect, when the current exceeds said predetermined threshold.

Electromagnetic triggers with known cross-sectional configuration have a pallet pivotally mounted between a rest position in which it is separated from the magnetic yoke and a position in which it is attracted magnetically until it comes into contact with said cylinder head.

Said pivoting pallet generally actuates a striker constituted of a part lying between it and a support arm of the movable contact. This one, also pivotally mounted, moves in an air gap of the cylinder head magnet opposite the pivoting pallet. Such a configuration is for example shown in EP 0 693 765 or EP 0 794 547.

These pivoting pallet configurations, however, are difficult to because of the compactness required by the low volume available, particularly in modular housings circuit breaker type devices.

So that the pivoting pallet can drive the firing pin with an energy appropriate kinetics, it is in principle necessary for the latter to have a sufficient which implies the existence of a non-negligible gap between the pallet and the cylinder head magnetic, requiring in turn a sufficient cylinder head volume to overcome the reluctance thus created. In addition to the volume of the cylinder head itself, the choice a pivoting pallet is not without impact on the size of the system, because to be able to train a striker in good conditions, it must have a relatively long length compared to the available volume in the case.

In other words, these configurations do not make it easy to play on stroke length without volume increase, which is hardly compatible with the requirements of compactness especially required in the housings of modular devices.

The present invention proposes to remedy this drawback by offering a configuration allowing in particular the increase of the stroke length without simultaneous increase in volume.

Another object of the invention consists in carrying out a configuration much easier to manufacture and mount than the rotary vane release.

According to yet another object, the invention can be implemented without major change in the two possible architectures resulting from the positioning of the fixed contact on one or other of the two conduction plates arc delimiting the arc extinction chamber of a circuit breaker.

• un noyau entouré d'au moins une demie spire de bobine excitatrice ainsi que d'une culasse conduisant le flux magnétique et munie d'un premier entrefer ménagé entre les extrémités de deux flans d'allure parallèle de la culasse, dans lequel se déplace un bras pivotant supportant le contact mobile ;
• un contact fixe disposé au voisinage dudit premier entrefer, et électriquement relié à la bobine ;
• au moins une palette qui réalise le déverrouillage du mécanisme à serrure et se déplaçe entre une première position de repos dans laquelle elle forme au moins un second entrefer avec la culasse et une position d'actionnement dans laquelle elle est attirée au contact de celle-ci ;
• un mécanisme de rappel de la palette dans sa première position ;

The electromagnetic release of the invention comprises, to fulfill the aforementioned objectives, as well as others which will appear on reading the description which follows, the following elements:

• a core surrounded by at least a half turn of exciter coil and a yoke driving the magnetic flux and provided with a first gap formed between the ends of two parallel-shaped flanks of the yoke, in which moves a pivoting arm supporting the movable contact;
• a fixed contact arranged in the vicinity of said first gap, and electrically connected to the coil;
• at least one pallet which unlocks the lock mechanism and moves between a first rest position in which it forms at least a second air gap with the cylinder head and an actuating position in which it is drawn in contact therewith ;
• a return mechanism of the pallet in its first position;

The essential characteristic of the trigger of the invention lies in that the pallet is movable and guided in translation in one side of the cylinder head following a stroke for unlocking the lock mechanism in case of overcurrent.

This translative configuration allows to modify the length of the race of the palette without substantially changing the trigger volume. She permits also lead to a much more compact configuration, the palette being almost totally integrated with the volume of the breech, unlike what exists in a rotating configuration.

Preferably, the air gaps relating to the pallet on the one hand, and to the supporting arm the movable contact on the other hand, are located on two contiguous sides of the breech. he This is another notable difference from rotating configurations in which the pallet is active on one side of the breech opposite to that which makes facing the arm supporting the moving contact.

More specifically, the yoke of the trigger of the invention is composed of two armatures equipping the ends of the nucleus and developing in the direction from each other on the sides provided with a gap.

According to one possibility, if there is only one pallet, this breech can be composed of two U's sharing the same jambs and whose bases in two perpendicular planes include the air gaps respectively of the arm supporting the moving contact and pallet.

So that the magnetic attraction at the origin of the displacement of the pallet can occur, it is obviously necessary that the pallet has at least one non parallel to the direction of movement.

Preferably, the latter has a shape, for example trapezoidal, adjusting in actuating position in the space between the two armatures.

This trapezoidal shape is particularly well adapted in that it allows the realization, in the rest position of the pallet, two air gaps obliques that generate attraction forces with a component parallel to the axis of movement of the pallet. The resultant parallel components audit axis generates its axial displacement towards the arm supporting the contact mobile.

According to one possibility, a firing pin is more firmly attached to the pallet, and has a stud protruding from its portion at the front considered relative to in the sense of displacement, intended to strike the lock mechanism for the unlock. This striker is not made of the same material as the pallet, since it does not have any magnetic function, but it is fixed there to fulfill its mechanical function.

In a variant, the pallet may comprise a means of attachment to the lock allowing the unlocking of the latter by traction when moving.

Preferably, the armatures of the cylinder head are symmetrical to one another by relative to a median plane transverse to the nucleus. This symmetry, which is not a functional need, nevertheless simplifies the manufacture and assembly of the magnetic release according to the invention.

In the same way, the reinforcements are notably positioned and fixed one by relationship to the other by a piece forming in addition a bottom to the space between said reinforcements in each side optionally comprising a pallet, each piece and its pallet being further provided with centering means and translational guidance of said pallet in said space.

This piece does not fulfill a magnetic function, but it facilitates the manufacture of the cylinder head, and therefore the trigger of the invention. It also has auxiliary mechanical functions allowing the striker to fulfill its function mechanical relative to the arm supporting the movable contact.

More specifically, said centering and guiding means consist of a slideway formed in said positioning and fixing part of frames, in which slides a profile reported to the pallet.

Preferably, there may be centering of the pallet with respect to the reinforcements although this is not an absolute technical necessity. This greatly facilitates the mechanical operation of the whole in order to confer on the pallet, and by therefore to the firing pin, sufficient kinetic energy to fulfill its function mechanical.

More preferably, the return mechanism of the pallet is set to said profile reported to the pallet.

According to one possibility, the pallets are two in number. Such a This configuration makes it possible, if necessary, to improve the mechanical performance of the trigger at the moment of disjunction.

In this case, the two pallets can be arranged in sides parallel of the trigger, or even be joined to each other.

Among the particular configurations that can be implemented, one may include a provision according to which the pallet cooperates directly with the arm supporting the movable contact for unlocking the lock.

• la figure 1 est une vue en perspective d'un déclencheur magnétique selon l'invention ;
• la figure 2 est une vue en perspective selon un angle différent du même déclencheur;
• la figure 3 est une vue en élévation du côté du déclencheur opposé à celui qui contient la palette mobile ;
• la figure 4 est une vue en élévation du côté coopérant avec le bras supportant le contact mobile ;
• la figure 5 est une coupe du déclencheur magnétique de l'invention selon les flèches V-V de la figure 3 ;
• la figure 6 est une coupe selon les flèches VI-VI de la figure 4 ; et
• la figure 7 est une coupe selon les flèches VII-VII de la figure 3.

The invention will now be described in more detail, in particular with reference to the appended figures for which:

• Figure 1 is a perspective view of a magnetic release according to the invention;
• Figure 2 is a perspective view at a different angle of the same trigger;
• Figure 3 is an elevational view of the trigger side opposite to that containing the movable pallet;
• Figure 4 is an elevational view of the side cooperating with the arm supporting the movable contact;
• Figure 5 is a section of the magnetic release of the invention according to the arrows VV of Figure 3;
• Figure 6 is a section along arrows VI-VI of Figure 4; and
• Figure 7 is a section along arrows VII-VII of Figure 3.

With reference to FIG. 1, the magnetic release according to the invention comprises a magnetic yoke formed of two armatures (1, 2) constituting a first air gap (3) within which moves an arm (4) supporting the moving contact, and a second gap (5) cooperating with a movable pallet (6).

These elements also appear in Figure 2, which shows, however, more precisely the shape of the pallet (6), and therefore the gap (5). They are trapezoidal in shape, the volume of the pallet (6) adapting exactly to the recess forming the air gap (5), in the actuating position. The forms of the gap (5) and the pallet (6) allow a displacement of the latter according to the arrow F, displacement that is counteracted below a certain value current threshold by the existence of a spring (R) shown diagrammatically in FIG. spring is for example fixed to the long side of the trapezium, whose small side is equipped with a striker (7) whose trajectory meets the arm (4) support of the contact movable when the pallet (6) moves from its rest position to its position actuating.

The conditions of disjunction lead to a sudden increase of current, creating a sufficient magnetic flux to create a force of attraction of the pallet (6) canceling the spring restoring force (R). The palette is moving, causing the striker (7) to move towards said arm (4) to achieve the separation of the contacts.

The mechanical and magnetic conditions are such that the kinetic energy of the striker is sufficient to pull the movable contact from the fixed contact in case of overcurrent generating disjunction.

The trigger of the invention is in fact a magnetic actuator sufficiently - powerful to proceed with the separation of the fixed and mobile contacts in the conditions that occur in case of overcurrent requiring disjunction.

These respectively fixed (8) and movable (9) contacts appear in FIG. as well as the coil (10) and the magnetic core (11). The engine thus created consumes little, and has a good performance because it has no gap parasite. It is therefore possible to reduce the number of turns.

In the case shown, the coil consists of a half turn of copper, which corresponds to a significant reduction in the amount of copper used and is economically quite favorable.

Figure 4 reveals the part (12) forming the bottom of the space between the reinforcement (1, 2), which assists the relative positioning of said armatures (1, 2), and which further comprises means for centering and guiding in translation of the pallet (6).

As mentioned previously, this piece (12) does not exert any magnetic function, and is therefore only necessary on a purely mechanical.

The sections constituting FIGS. 5 to 7 make it possible to clarify the arrangement relative of the different constituents of the trigger according to the invention. Thus, Figure 5 particularly shows the mechanical relationship between the pallet (6) on the one hand and the firing pin (7) on the other hand. The sliding relationship between the pallet (6) and the connecting piece (12) is also represented in this figure.

Figures 6 and 7 illustrate the structure of the magnetic yoke represented by the frames (1, 2). It develops in such a way that it forms a U in two perpendicular planes which are precisely represented respectively in Figures 6 and 7.

In the plane of FIG. 6, the base of the U is interrupted by the gap (3) in which moves the support arm (4) of the movable contact (9).

In the plane shown in FIG. 7, the base of the U is interrupted by the gap (5) in which the pallet (6) moves. This one is mechanically connected to the piece (12) via sliding means (13) which move in a slide in said part (12).

The description above is of course only one possible example of implementation of the invention. This also includes variant shapes and configurations that are within the reach of those skilled in the art, as defined in the claims.

Claims (15)

1. Electromagnetic tripping device for electrical equipment, in particular of the modular circuit breaker type, provided with a fixed contact (8) interacting with a contact (9) which can be moved between two positions, respectively against and away from the fixed contact (8), the said moving contact (9) being connected to a lock mechanism for controlling the position of the moving contact (9) with respect to the fixed contact (8), the tripping device interacting with this lock mechanism and being able to release it with a view to opening the contacts (8, 9) if there is a surge in the current flowing through the electrical equipment, the said circuit breaker including:

   a core (11) enclosed by at least one half-turn of an excitation coil (10), as well as a yoke (2) which conducts the magnetic flux and is provided with a first air gap (3) formed between two flats shaped parallel to the yoke (2), in which a pivoting arm (4) that supports the moving contact (9) is moved;

   a fixed contact (8) arranged in the vicinity of the said first air gap (3) and electrically connected to the coil (10);

   at least one plunger plate (6) which is used to release the lock mechanism and is moved between an inactive first position, in which it forms at least one second air gap (5) with the yoke (2), and an actuation position in which it is attracted into contact with the latter; and

   a restoring mechanism (R) for returning the plunger plate into its first position;

   characterised in that the plunger plate (6) can be moved and is guided in translation on one side of the yoke (2) over a range of travel making it possible to release the lock mechanism if there is a current surge.
2. Electromagnetic tripping device according to the preceding claim, characterised in that the yoke is formed by two armatures, which are fitted to the ends of the core and are developed in the direction of each other on the sides provided with an air gap.
3. Electromagnetic tripping device according to the preceding claim, characterised in that the plunger plate has at least one side which is not parallel to the direction of the movement.
4. Electromagnetic tripping device according to one of Claims 2 and 3, characterised in that the plunger plate has a shape which, in the actuation position, fits into a space formed between the two armatures.
5. Electromagnetic tripping device according to one of the preceding claims, characterised in that a striker is secured to the plunger plate and has a stud, extending beyond its portion located at the front with respect to the direction of the movement, which is intended to strike the lock mechanism in order to release it.
6. Electromagnetic tripping device according to one of Claims 1 to 5, characterised in that the plunger plate includes a means of engaging with the lock, making it possible to release the latter by traction when it is moved.
7. Electromagnetic tripping device according to one of Claims 2 to 6, characterised in that the said armatures are mutually symmetrical with respect to a median plane transverse to the core.
8. Electromagnetic tripping device according to any one of Claims 2 to 7, characterised in that the armatures are, in particular, positioned and fixed with respect to each other by a piece forming a base for the space formed between the said armatures in each side which has a plunger plate, each piece and its plunger plate being provided with means for centring the said plunger plate and guiding it in translation in the said space.
9. Electromagnetic tripping device according to the preceding claim, characterised in that the said centring and guiding means consist of a slideway, formed in the said piece for positioning and fixing the armatures, in which slides a profiled section attached to the plunger plate directly or via a connecting piece.
10. Electromagnetic tripping device according to the preceding claim, characterised in that the restoring mechanism of the plunger plate is fixed to the said profiled section attached to the plunger plate.
11. Electromagnetic tripping device according to any one of the preceding claims, characterised in that the shape of the plunger plate is trapezoidal.
12. Electromagnetic tripping device according to any one of the preceding claims, characterised in that there are two plunger plates.
13. Electromagnetic tripping device according to the preceding claim, characterised in that the plunger plates are arranged in parallel sides of the triggering mechanism.
14. Electromagnetic tripping device according to the preceding claim, characterised in that the plunger plates are secured to each other.
15. Electromagnetic tripping device according to one of Claims 1 to 11, characterised in that the plunger plate interacts directly with the arm which supports the moving contact, with a view to releasing the lock.

Images