EP0079819B1 - Mechanically operated switch with automatic opening - Google Patents

Abstract

A mechanically controlled power switch with automatic opening is provided for limiting short circuits. A switch (13), a breaking chamber (30) which is associated therewith, a coil (50), a striker (51) cooperating therewith, and a lock (53) for holding the power switch in open position S after the appearance of a short circuit are placed in a removable cartridge (23) provided with connection terminals (37, 55). This switch cartridge is advantageously used in mechanically controlled protection apparatus or in electromagnetic contactor apparatus having their own protection.

Description

• - un boîtier;
• - une chambre de coupure pourvue d'ailettes de fractionnement des arcs;
• - un interrupteur de puissance placé dans cette chambre et ayant au moins un contact fixe et un contact mobile qui est actionné par un poussoir et qui est soumis à l'action d'un ressort de compression fixe tendant à l'appliquer sur le contact fixe;
• - une bobine qui est placée en série dans un circuit où se trouve l'interrupteur et qui est apte à attirer un percuteur magnétisable lorsque le circuit est parcouru par un courant de court-circuit;
• - un dispositif de commande ayant une pièce mobile qui coopère par poussée avec le poussoir pour déplacer le contact mobile, et
• - des bornes d'entrée et de sortie pour raccorder l'interrupteur, ce percuteur coopérant avec ce poussoir de façon à déplacer celui-ci lors de son attraction et indépendamment de la pièce mobile, et à l'amener dans une position où un dispositif de verrouillage maintient l'interrupteur dans une position d'ouverture de sécurité.

The invention relates to a switch with mechanical control and automatic opening for a limiting protective device, device comprising:

• - a housing;
• - a breaking chamber provided with arc splitting fins;
• - a power switch placed in this chamber and having at least one fixed contact and one movable contact which is actuated by a pusher and which is subjected to the action of a fixed compression spring tending to apply it to the fixed contact ;
• - a coil which is placed in series in a circuit where the switch is located and which is capable of attracting a magnetizable striker when the circuit is traversed by a short-circuit current;
• a control device having a movable part which cooperates by pushing with the pusher to move the movable contact, and
• - input and output terminals for connecting the switch, this striker cooperating with this pusher so as to move the latter during its attraction and independently of the moving part, and to bring it into a position where a device Lock keeps the switch in a safety open position.

Such switches are in particular used in protective devices where the power contacts are used at the same time for the frequent establishment and breaking of the supply circuits which are usually controlled by contactors.

In a known device, the constitution of which corresponds to that which is defined above, no measure is taken to allow the replacement of fixed or mobile contacts; such measures, which nevertheless meet one of the constant concerns of users, encounter in this particular case difficulties due, in particular, to the relative complexity of the device; it is therefore desirable to make this operation as simple as possible, by giving the user means which allow him to carry out such operations quickly and which do not offer the possibility of incorrect mounting.

It is desirable, moreover, to make it possible to change the contacts without it being. necessary to separate the terminals of the network and load protection device, and to provide users with a range of contacts whose dimensions, as well as those of the coil, correspond to different current ratings and to different limitation levels.

According to the invention, this result is achieved by the fact that the switch, the breaking chamber, the coil and the striker, as well as the locking device, are placed in a removable insulating cartridge which is placed in a housing of the the device and which presents externally, on the one hand, two connection terminals which cooperate with terminals of the protection device going towards the network or towards a user device and between which the coil and the switch are placed in series, and, on the other hand, in a region opposite to the breaking chamber, one end of the pusher capable of cooperating with the moving part of the control device, and one end of the locking device capable of communicating a movement when the switch is maintained in the safety opening position, guiding and holding means being placed on this cartridge to ensure this cooperation and the communication of this movement.

The invention, as well as other complementary measures, will become clear with the aid of the detailed description below.

• les fig. 1 a et 1 b représentent schématiquement deux appareils de protection à commande mécanique, respectivement électromagnétique, dans lesquels est mis en oeuvre l'objet de l'invention ;
• la fig. 2 montre, dans une vue en élévation coupée par un plan médian PP', une cartouche conforme à celle de l'invention, un interrupteur à double coupure étant à l'état fermé;
• la fig. 3 illustre une vue de côté gauche de la cartouche coupée par un plan brisé QQ', l'interrupteur étant fermé;
• la fig. 4 représente une vue en élévation de la cartouche avec coupe locale, l'interrupteur étant en position d'ouverture de sécurité;
• la fig. 5 montre une vue de côté de la cartouche avec coupe locale par le plan QQ' lorsque l'interrupteur est en position d'ouverture de sécurité;
• la fig. 6 illustre une vue extérieure en élévation de la cartouche selon l'invention;
• la fig. 7 représente l'appareil selon la fig. 2 dans l'état d'ouverture commandée de l'interrupteur, et
• la fig. 8 illustre une cartouche selon l'invention utilisant un interrupteur à simple coupure.

In the accompanying drawings:

• fig. 1 a and 1 b schematically represent two protective devices with mechanical control, respectively electromagnetic, in which the object of the invention is implemented;
• fig. 2 shows, in an elevation view cut by a median plane PP ', a cartridge in accordance with that of the invention, a double-break switch being in the closed state;
• fig. 3 illustrates a left side view of the cartridge cut by a broken plane QQ ', the switch being closed;
• fig. 4 shows an elevational view of the cartridge with local section, the switch being in the safety opening position;
• fig. 5 shows a side view of the cartridge with local section through the plane QQ 'when the switch is in the safety opening position;
• fig. 6 illustrates an external elevation view of the cartridge according to the invention;
• fig. 7 shows the apparatus according to FIG. 2 in the state of controlled opening of the switch, and
• fig. 8 illustrates a cartridge according to the invention using a single cut-off switch.

The limiter switch which will be described below can be used in a protective device shown diagrammatically at 1 in FIG. 1 a; this device mainly comprises, in a housing 2, an automatic switch 3 whose safety opening in the event of the occurrence of a fault current, in particular of short circuit, is operated using a coil 4 placed in series with this switch between an input terminal 5 connected to the network R and an output terminal 6 connected to a load C, and a manual control device 7 whose operation produces the rapid opening or closing of the switch thanks to a movable control piece 8 acting on a push-button 9 of the switch, while a fault signaling member 10 associated with the switch acts on the manual control device 7 to give it, when a fault appears , a special state which interrupts the action of the control device and confirms automatic opening. This limiting switch can also be used in a contactor device having additional functions for limiting the current (and possibly circuit breaker) shown diagrammatically at 11 in FIG. 1 b; like the previous one, the latter device comprises, in a housing 12, a switch 13 and a coil 14, placed in series between the terminals 15, 16, similar to those of the switch 3, but whose repeated closing and opening control is carried out by an electromagnet 17 of which a movable control part 18 cooperates with the pusher 19 of the switch 13, while the fault signaling member 20 acts directly or indirectly on a control contact 21 placed in series with the coil 22 of the electromagnet so as to confirm, if necessary, the automatic safety opening by de-excitation of this electromagnet.

Additional terminals 25, 26 are used here to apply a control signal to the electromagnet.

In one or other of the possible applications, the switch 3, 13, which is contained in a removable insulating cartridge 23 which can be separated from the housing 1, 11, can be single or double cut, and it is clear that the number of cartridges used in a device corresponds to the number of network phases.

The insulating cartridge 23, as well as its contents, appears better in FIG. 2 where it is observed that this cartridge takes the general form of an L having a first branch 27 and a second branch 28 substantially perpendicular.

The first branch 27 contains a first volume 29 in which are arranged the switch 3, respectively 13, and a breaking chamber 30 which is associated therewith and which comprises, in known manner, fins 31, 32 for the splitting of the arcs.

This switch comprises, in the example shown, two fixed contacts 33, 34 which are carried by folded conductors 35, respectively 36, one of which leads to a first connection terminal 37 external to the cartridge; a movable bridge contact 38 is carried by a movable contact carrier 39 which can move along an axis ZZ ′ thanks to guide surfaces 40 of the cartridge. The movable contact and the contact carrier are subjected to the action of a fixed compression spring 41 which tends to close the switch by pressing on an internal end 42 of the contact carrier and on a wall 43 of the cartridge.

The folded shape of the conductors 35, 36 allows the development of repulsion forces on the movable contact bridge 38 which runs parallel to them.

A second end 44 of the contact carrier 39, opposite the first, is placed outside the first volume and has a first bearing surface 45, directed towards the spring 41, and an elongated opening 46 having a second bearing surface 47 , also directed towards the spring.

The second branch 28 contains a second volume 48 in which are arranged, on the one hand, a magnetizable yoke 49, a coil 50 which is associated with it and a magnetizable striker 51 of the plunger core type and, on the other hand, a lever for transmission 52 and a locking lever 53.

The ends of the coil 50 are connected, on the one hand, to the folded conductor 36, for example using a flexible conductor 54, and, on the other hand, to a second external connection terminal 55. The striker , which takes a rest position, visible in fig. 2 (for example using a spring not shown), can move along an axis VV 'which is also that of the coil 50 and which is substantially parallel to the axis ZZ'.

The transmission lever 52, which moves in a median plane PP 'of the cartridge thanks to a pivot or pin 56 whose axis is perpendicular to this plane, has a free end 57 which penetrates into the elongated opening 46 of the door contact 39 so as to be able to cooperate with the second bearing surface 47, and a central portion 58 placed opposite one end 59 of the striker; a return spring 60 is associated with this transmission lever to hold it elastically against a fixed stop 61 in a rest position R which is that shown in FIG. 2.

The locking lever 53 oscillates around a pivot 62 whose axis YY 'is parallel to the median plane PP' or passes through it; this axis YY 'is substantially perpendicular to the axis VV' of the coil. A return spring 63, placed for example around the pivot 62, communicates to this locking lever 53 a torque K counterclockwise, visible in particular in FIG. 3, which makes it apply a first end 64 against a lateral face 65 of the transmission lever and which gives a second end 66 of the locking lever 53, outside the second volume, a particular position I.

Note that the transmission lever 52 is placed between the first volume 29 and the coil 50, and that the outer end 44 of the contact carrier acting as a pusher moves in the vicinity of the second branch 28 of the cartridge in a region 75 opposite the breaking chamber 30, while the outer end 66 of the locking lever 53 moves at the end of this second branch 28 in a region 76 also opposite the breaking chamber.

The cartridge 23 is preferably produced by the association of two insulating half-housings 67 and 68 (see fig. 3) which are applied one on the other along a joint plane coincident with the median plane PP 'and are kept in contact either by elastic hooks coming from molding with the half-housings, or by external metal clamps, or even by rivets.

When the switch must be open and set to position 0 (see fig. 7), the contact carrier 39 receives on its first bearing surface 45 a thrust of direction F which is given to it by a part 8, 18 of the device mechanical control 7 or electromagnetic control 17; thanks to a clearance j existing between the end 57 of the transmission lever 52 and the elongated opening 46, this movement has no effect on this transmission lever; the switch closes under the effect of the spring 41 when the action on the contact carrier 39 ceases. When the switch is in the closed position and a very intense current flows in the coil, the striker 51 is attracted by the coil and the cylinder head and pushes back the transmission lever 52, against the action of its spring return 60, so that its end 57 exerts on the second bearing surface 47 a safety opening action of the contacts of the switch.

As soon as the transmission lever reaches or exceeds a working position T, visible in fig. 4 and 5, for which this current has been sufficiently limited, the internal end 64 of the locking lever passes over an edge 69 of the transmission lever 52 to maintain it in this position T where the switch is now at open security state S.

During this operation, the locking lever 53 takes an active position A, visible in FIG. 5, under the effect of its return spring 63.

The displacement of the outer end 66 of this locking lever is used either to confirm the opening of the switch 3, 13 by a mechanical action provided by the device 7, 8 of FIG. 1a, either to open, directly or not, the switch 20 of the control electromagnet 17, 18, all by means of a transmission part such as 90 (fig. 8).

In both cases, a specific signal can be issued to inform maintenance personnel that the automatic opening is due to the appearance of a short-circuit current.

As seen in particular in FIG. 4, measures can be taken so that the cooperation between the moving parts placed in the second volume 48 takes place under good conditions. Thus the stop 61 of the transmission lever 52 and the pivot 62 of the locking lever 53 are both carried by the cylinder head 49, a cylindrical bush 70 of which serves to guide the striker 51.

The cartridge 33 is also guided in the housing of the device which receives it by means of grooves 71, 72 parallel to the axis ZZ ', which are placed on the opposite external faces 73, 74 parallel to the contact carrier plane ( fig. 6 and 3).

In particular, on examining FIGS. 3 and 5, that the cartridge 23 occupies a small width d, which makes it possible to place several side by side in parallel cells 1 ′, 11 ′, of an apparatus 1 or 11 designed to use them, without however give it important dimensions.

The contact carrier 39, shown in the previous figures and acting as a pusher, can also be replaced by another pusher 77 to act on a movable contact with single break 78, visible in FIG. 8, which is returned by a spring 81 and cooperates with a single fixed contact 79 of switch 3.

In this same figure, it can be seen that the cartridge 23 is held in a cell 1 ', respectively 11', of the apparatus thanks to the cooperation, on the one hand, of surfaces such as 84, 85 with walls 86.87 the housing 1,11 and, on the other hand, surfaces such as 88 with a cover 89 closing the cell. In this situation, the external terminals 37 and 55 of the cartridge cooperate with the internal terminals 82, 83 of the housing 1 going towards the connection terminals 5, 6, respectively 15, 16, of the device which receives it, while the end 66 of the locking lever transmits its possible displacement to a transmission part 90 whose purpose is to trigger the mechanical device 7 or the control switch 21 of the electromagnetic device 17.

Resetting of the locking 53 and transmission 52 members is obtained by communicating at the end 66, by means of manual or automatic control not described, a movement of direction G (FIG. 5).

Claims (6)

1. A mechanically controlled switch (13, 3) with automatic opening for a protective limiting apparatus (1, 11 ), this apparatus comprising:

- a case (2) ;

- a breaking chamber (30) having fins (31, 32) for fractioning the arcs;

- a power switch placed in this chamber and having at least one fixed contact (33, 34) and one mobile contact (38) which is actuated by a push-button (39) and which is subject to the action of a fixed compression spring (41) tending to apply it against the fixed contact (33, 34);

- a coil (50) which is placed in series in a circuit containing the switch (13, 3) and which is adapted to attract a magnetizable striker (51) when the circuit has a short-circuit current passing therethrough;

- a control device having a mobile part (8,18) which co-operates by pushing with the push-button (39) to move the mobile contact (38), and

- input and output terminals for connecting the switch (13, 3),

this striker (51) co-operating with this push-button (39) so as to move this latter when the striker is attracted and independently of the mobile part (8, 18), and to bring the push-button into a position where a locking device (53) holds the switch (13, 3) in an open safety position, characterized in that the switch (13, 3), the breaking chamber (30), the coil (50) and the striker (51), as well as the locking device (53), are placed in a removable insulating cartridge (23) which is placed in a housing (1', 11') of the apparatus (1,11) and which has externally, on the one hand, two connecting terminals (37, 55) which co-operate with terminals (82, 83) of the protection device not directly connected to the network or to a user apparatus, and between which are placed in series the coil and the switch, and which has, on the other hand, in a region (75) opposite the breaking chamber, one end (44) of the push-button (39), respectively (77), adapted to co-operate with the mobile part (18, 8) of the control device (7, 17) and one end (66) of the locking device (53) adapted to communicate a movement for triggering the control device when this switch is held in the open safety position (S); guide means (71, 72) and holding means (84, 85, 88) being placed on this cartridge for giving to this latter a position ensuring this co-operation and the communication of this movement.

2. The switch according to Claim 1, characterized in that the insulating cartridge (23) is formed by a flat case (23) having two distinct adjacent volumes so as to assume the general shape of an L, in each of the legs (28,27) of which are located a first volume (29) and respectively a second volume (48), the first volume receiving the switch (3, 13) and the breaking chamber (30), whereas the second volume receives the coil (50), the striker (51 ) and the locking device (53).

3. The switch according to Claim 2, characterized in that the outer end (44) of a contact holder (39) or push-button (77) moves parallel to the leg (28) of the cartridge (23) containing the second volume (48) in a region (75) proximate the two legs (27, 28).

4. The switch according to one of Claims 1,2 or 3, characterized in that the locking device comprises a transmission lever (52) with resilient return (60), which rocks in a median plane (PP') of the cartridge about a first pivot (56) and one end of which (57) co-operates with an outer end (44) of the contact holder or push-button (39, 77), and a resilient locking lever (53,63) which rocks about a second pivot (62) whose axis (YY') is parallel to said plane (PP'), this transmission lever being disposed between the first volume (29) and the coil (50) so as to receive the action of the striker (51 ) between the first pivot (56) and the end (57).

5. The switch according to Claim 4, characterized in that the locking lever (53) is placed in the vicinity of the outer end (44) of the contact holder or push-button (39, 77) and has a second end (66) which is opposite the first end (64) and which is placed outwardly in a region (76) of the second leg (28) opposite the breaking chamber (30) so as to communicate a movement to the mechanical (7) or electro-magnetic (17) control device.

6. The switch according to Claim 5, characterized in thatthe first end (64) of the locking lever (62) is resiliently applied against a lateral surface (65) of the transmission lever (52) when this latter is in rest position (R), and passes above an edge (69) of the transmission lever when this latter takes up a working position (T).

Images