FR2838556A1 - Low voltage multipolar electrical switch/circuit breaker having single bar and closure contact spring with opening spring having pressure above closure spring. - Google Patents

Abstract

The switch has several power poles (L1,L2,L3) with a fixed (10) and moving part. There is a pusher section, contact spring (23) and contact bridge. Each pole has an opening spring (22) opposing the contact spring. The opening spring pressure is above that of the closing spring.

Description

in the primary part of the heat exchanger (7a, 7b).

  The present invention relates to a multi-pole low voltage electrical switch device of the contactor, circuit breaker or circuit breaker contactor type, the movable contacts of the different poles of which are controlled by a single control electromagnet. Such a switching device comprises in known manner several power poles each comprising, in the case of single-break poles, a fixed contact cooperating with a corresponding movable contact in order to open or close a circuit for supplying an electrical load . Equivalently, in the case of double-break poles, each power pole has two fixed contacts cooperating with two corresponding movable contacts. The movable contact (s) of a pole are generally placed on a movable bridge which is mechanically actuated, between the closed position and the open position, by an actuator, such as a pusher or a slide, and by a pressure spring. The pusher cooperates with the mobile part of a control electromagnet, composed for example of a mobile pallet, a plunger core or a mobile armature, the movement of which is a function of a control current flowing in a coil excitation of the control electromagnet. Usually, for reasons of simplification, synchronization of movements and efficiency of the switching device, a single control electromagnet is sufficient to simultaneously drive the pushers of the different poles to

  carry out the closing and opening movements.

  However, during a contact opening movement, the mechanical drive of the pole pushers could be disturbed if the fixed and mobile contacts of one of the poles were to weld together, which could happen at the end of the life of the pole. 'switch device, when there are no more contact pads on the fixed or mobile contacts. In this hypothesis, if the mobile bridge of a pole could no longer move due to a weld at its contacts, then the mechanical connection existing between the pusher between the mobile bridge of the pole and the mobile part of the electromagnet could hinder the free movement of this mobile part, which, in the worst case, could therefore compromise the movement of other poles whose contacts are not welded. In such an extreme case, the control electromagnet of a switching device having a welded pole contact would then no longer be able to open the load supply circuit.

  electric, causing a potentially dangerous situation.

  The object of the invention is to remedy this drawback by proposing a simple and inexpensive solution making it possible to ensure, even in the event of soldering of the contacts at one of the poles of a switching device, sufficient opening of the contacts. other power poles of the switch device, so that

  nevertheless interrupt the supply of the electrical load satisfactorily.

  For this, the invention describes an electrical switch device comprising several power poles and an electromagnet for controlling the poles provided with a fixed part and with a mobile part, each pole comprising a pusher cooperating with the mobile part of the electromagnet. , a contact closing spring and a contact bridge which is movable, under the effect of the push button and the pole closing spring, between an open position and a closed position. Each pole also includes a pole opening spring acting in opposition to the pole closing spring

  and whose pressure force is greater than the force of the pole closing spring.

  According to a first variant, the opening spring of a pole presses on one side on the pusher of the pole and on the other opposite side on a first face of the movable bridge of the pole, promoting an opening movement of the movable bridge . The closing spring of a pole bears on one side on a fixed base of the switch device and on the opposite opposite side on a second face of the movable bridge of the pole opposite to the first face,

  favoring a closing movement of the movable bridge.

  According to a second variant, the opening spring of a pole bears on one side on the movable part of the electromagnet of the switching device and on the other opposite side on a face of the pusher located opposite the part mobile of the electromagnet, between the mobile bridge and the mobile part of the electromagnet, favoring an opening movement of the mobile bridge. The closing spring of a pole presses on one side on a second end of the pole pusher and on the other opposite side on a second face of the movable bridge of the pole, promoting a closing movement of the movable bridge.

  Other characteristics and advantages will appear in the description.

  detailed below with reference to an embodiment given by way of example and represented by the accompanying drawings in which: - Figure 1 shows a block diagram showing the poles of a switch device according to the invention, in position closed, Figure 2 shows the example of Figure 1 in the open position, when one of the poles is welded, - Figure 3 shows another embodiment showing the poles of a switch device according to the invention, closed position, - Figure 4 shows the example of Figure 3 in the open position, when one

of the poles is soldered.

  With reference to the exemplary embodiments of FIGS. 1 to 4, a low-voltage electrical switch of the contactor, circuit breaker or contactor / circuit breaker type comprises three power poles L1, L2, L3 of the same kind each comprising two fixed contacts 32a, 32b cooperating with two corresponding movable contacts 31a, 31b, for the purpose of closing or opening a three-phase supply circuit of an electric charge not shown. The examples presented are double-break poles, but the invention applies equally to single-break poles. On each pole, the movable contacts 31a, 31b are placed on the first face 35 of a movable conductive bridge 30. The movable bridge 30 moves along a longitudinal axis X between a closed position, in which the fixed contacts 32a, 32b and mobile 31a, 31b are in contact, and an open position, in which the fixed contacts 32a, 32b and mobile 31a, 31b are separated. In FIGS. 1 and 3, the supply circuit is in the closed position, which makes it possible to circulate an electric current in each pole between an upstream fixed conductor 33a, carrying the

  fixed contact 32a, and a downstream fixed conductor 33b, carrying the fixed contact 32b.

  For reasons of simplification and clarity of the drawings, the power poles are arranged in the same longitudinal plane in the different figures, rather than in an arrangement along several parallel planes which would be more in accordance with their actual location in a switching device. . The first variant shown in Figures 1 and 2 shows a mechanism for closing and opening poles called "breaker poles", while the second variant shown in Figures 3 and 4 shows a mechanism for closing and opening poles called "contactor poles". As is known, either of these

  mechanisms can be used in an electrical switch.

  In the first variant of Figures 1 and 2, the movable bridge 30 of a pole is mechanically actuated along the axis X on the one hand under the action of a contact closure spring 23 and on the other hand under the action of a movable actuator 20, by means of a contact opening spring 22. The movable actuator 20 is either a pusher 20, a slide or any other driving mechanical part. The closing spring 23, which is for example in the form of a cylinder or truncated cone, has a first end which rests on a fixed base 12 of the switching device and a second opposite end which rests on a second face 36 of the movable bridge 30 opposite to the first face 35, thus favoring a closing movement of the movable bridge 30. The pusher 20 comprises a transverse recess 25 in which the movable bridge 30 is inserted, the movable contacts 31a, 31b being placed on either side pusher 20. This recess 25 is designed to be sufficiently large to allow the pusher 20 to slide relative to the movable bridge 30 inside the recess 25 of a predetermined stroke D along the axis

  longitudinal X, between a lower edge 28 and an upper edge 29 of the recess 25.

  According to the invention, each pole also includes a contact opening spring 22. This opening spring 22, preferably of cylindrical shape, bears on one side on the first face 35 of the movable bridge 30 and rests on the opposite side on one face of the pusher 20, located opposite the movable bridge 30, between the pallet 10 and the movable bridge 30. Thus positioned, the opening spring 22 promotes an opening movement of the movable bridge 30. One end of the spring opening 22 is advantageously housed and held in a central cavity 24 of the pusher 20. The opening spring 22 therefore acts in opposition to the closing spring 23 and it is designed to have a pressure force greater than the closing spring 23. For example , we can imagine a force of 3.5 N (Newtons) for the opening spring 22

  against a force of 2.5 N for the closing spring 23.

  The switching device comprises a control electromagnet, a movable part 10 of which is shown diagrammatically in the figures in the form of a movable pallet 10. It would also have been possible to use either an electromagnet, the movable part of which would be composed of a movable armature, d 'a movable core, etc. Usually, the movement of this movable pallet 10 is generated, in the opening to closing direction (i.e. in the direction of the arrow F), by circulation

  a control current in an excitation coil of the electromagnet.

  Conversely, the movement of the movable pallet 10 is generated, in the closing to opening direction (that is to say in the direction of the arrow O), by a return spring not shown which acts on the movable pallet 10 in if the control current in the coil disappears. The switch device comprises a single movable part 10 of the electromagnet which cooperates with the different pushers 20 of poles, thus allowing

  to control all the poles simultaneously.

  The operation of a breaker pole mechanism will now be described. In the closed position of Figure 1, the pallet 10 of the electromagnet is not in contact with the pusher 20 of the poles, leaving them a free movement along the axis X. The opening spring 22 cannot therefore act on the movable bridge 30 since its first end pressing on the pusher 20 is not kept fixed. Consequently, this releases the action of the contact closure spring 23 which can then

  exert contact pressure between the fixed contacts 32a, 32b and movable 31a, 31b.

  In the closed position, maintenance of the pusher 20 is nevertheless ensured by virtue of the lower edge 28 of the recess 25 of the pusher 20 against which the second rests.

face 36 of the movable bridge 30.

  During the transition to the open position of FIG. 2, the pallet 10 moves in normal operation along the arrow O. by a sufficient distance to come into contact and press the pusher 20 of the different poles. The opening spring 22, which is held by the pusher 20, then exerts pressure on the first face 35 of the movable bridge 30. The opening spring 22 works in opposition to the closing spring 23 and, as it is designed to have a pressure force greater than that of the closing spring 23, this causes movement of the movable bridge 30

  causing the separation of the movable contacts 31a, 31b and fixed 32a, 32b.

  In a switching device having no opening spring 22 as described in the invention, if one of the poles L1, L2, L3 has a fixed contact which is welded with a corresponding movable contact, this will jam the movement of the bridge mobile 30 of this defective pole in the closed position and therefore block the pusher 20 of the pole, this situation possibly going as far as hampering the opening movement of the pallet 10. It is then possible that we can no longer guarantee an opening i sufficient for none of the poles of the switch device, requiring the use of a

  upstream protection device, for example.

  Thanks to the invention, if a pole L1 remains in the closed position by welding one of its contacts, blocking the corresponding movable bridge 30 in the closed position as indicated in FIG. 2, the operation of the opening movement is as follows: when the movable pallet 10 will come into contact with the pusher 20 of the pole L1, despite the immobilized movable bridge, the presence of the opening spring 22 will nevertheless make it possible to avoid the blocking of this pusher 20. In fact, the spring of opening 22 will compress under the effect of the pallet 10, of course subject to the sufficient pressing force of the return spring of the electromagnet. This compression will allow the displacement of the pusher 20 on a displacement D, until the upper edge 29 of the recess 25 of the pusher 20 comes into contact with the first face 35 of the movable bridge 30. Consequently, the movement of the pallet 10 is not hindered and remains possible over this entire distance D which must be determined to allow sufficient opening of the other non-welded poles L2, L3. Thus, by opening two out of three power poles, the supply of

  the electric charge and a potentially dangerous situation is avoided.

  Figures 3 and 4 show a second equivalent variant of the invention

  in which a switching device has a contactor pole mechanism.

  As in the first variant, the switch device comprises a control electromagnet, a movable part 10 'of which is shown diagrammatically in the figures in the form, for example, of a movable pallet 10'. The movable pallet 10 'comprises for each pole at least one finger 12', preferably two, each terminated by a retaining lug 13 '. Usually, the movement of the movable pallet 10 is generated, in the opening to closing direction (i.e. arrow F), by the circulation of a control current in an excitation coil of the electromagnet. . Conversely, the movement of the movable pallet 10 'is generated, in the closing to opening direction (that is to say arrow O), by a return spring not shown which acts on the movable pallet 10' in the event of disappearance control current in the coil. The switching device comprises a single movable part 10 'of the electromagnet which cooperates with the different pushers 20' of poles, thus making it possible to control simultaneously

all the poles.

  In this second variant, the movable bridge 30 of a pole is actuated mechanically along the axis X on the one hand under the action of a movable pusher 20 ', or of a slide or equivalent, and on the other hand under the action of a contact closure spring 23. The pusher 20 'comprises a transverse recess 25' in which the movable bridge 30 is inserted between a lower edge 28 'and an upper edge 29' of the recess 25 ' , the movable contacts 31a, 31b being placed on either side of the pusher '. The closing spring 23, which is for example in the form of a cylinder or truncated cone, has a first end which rests on the lower edge 28 'of the pusher 20' and a second opposite end which bears on the second face 36 of the movable bridge 30 opposite the first face 35, thus favoring a movement for closing the movable bridge 30. Furthermore, the pusher 20 ′ has at one end one, preferably two, flanges 21 ′ which cooperate with retaining lugs 13 ′ corresponding to the 10 'pallet, so that the 10' pallet can

  macanically entrain the pusher 20 'during the closing movement.

  According to the invention, each pole comprises a contact opening spring 22. This opening spring 22, preferably of cylindrical shape, rests on one side on the pallet 10 'and presses on the opposite side on a face 26' of the pusher 20 ', located opposite the pallet 10' between the movable bridge 30 and the pallet 10 '. Thus positioned, the opening spring 22 favors an opening movement of the movable bridge 30. Preferably, one end of the opening spring 22 is housed and held in a central cavity of the pusher 20 '. As for the first variant, the opening spring 22 acts in opposition to the closing spring 23 and it

  is designed to have a pressing force greater than the closing spring 23.

  The operation of a contactor pole mechanism is as follows. In the closed position as shown diagrammatically in FIG. 3, the pallet 10 ′ of the electromagnet drives in the direction of arrow F the pusher 20 ′ of the poles by means of the retaining lugs 13 ′ of the fingers 12 ′ which act on the flanges 21 ′ . The movable bridge 30 is then no longer in contact with the upper edge 29 'of the pusher 20'. The lower edge 28 ′ of the pusher 20 ′ also move, this then allows the contact closure spring 23 to exert contact pressure between the fixed contacts 32a, 32b and movable contacts 31a, 31b. Thus, it can be noted that, in the case of a mechanism with contactor poles, to pass into the closed position, the electromagnet of the switching device must be able to overcome the force of the return spring of the electromagnet plus l force of the closing spring 23 of the poles, while in a breaker pole mechanism, to pass into the closing position, the electromagnet of the switching device must only be able to overcome the force of the return spring of the electromagnet . During the transition to the open position of FIG. 4, the pallet 10 'moves in the direction of arrow O. The opening spring 22, which acts between the pallet 10' and the pusher ', supports the upper edge 29' of the pusher 20 ′ with the first face 35 of the movable bridge 30. Then, as the opening spring 22 is designed to have a pressure force greater than that of the closing spring 23, the movement of the pallet ’causes a movement of the bridge mobile 30 causing contact separation

mobiles 31a, 31b and fxes 32a, 32b.

  Thanks to the invention, if a pole L1 remains in the closed position by welding one of its contacts, blocking the corresponding movable bridge 30 in the closed position as indicated in FIG. 4, the operation of the opening movement is as follows: when the upper edge 29 ′ of the pusher 20 ′ of the pole L1 will come to bear against the first face 35 of the movable bridge 30, the latter will remain immobilized. The opening spring 22 will then compress under the effect of the pallet 10 ', subject to the sufficient pressing force of the return spring of the electromagnet. This compression of the opening spring 22 will allow the movement of the pallet 10 'over a distance D, until the end of the pusher 20' comes into contact with the pallet 10 '. Consequently, the movement of the pallet 10 ′ will no longer be hampered over this entire distance D which must be determined to allow sufficient opening of the other non-welded poles L2, L3. Thus, by opening two out of three power poles, the supply of the electrical load is nevertheless interrupted and a situation is avoided

potentially dangerous.

  Incidentally, when a pole L1 is welded, it should be noted that the compression of the opening spring 22 during an opening movement will advantageously generate a pressure force exerted on the first face 35 of the movable bridge 30 of this pole L1 which can, in such a situation, favor the

  take-off and separation of the welded contacts from the L1 pole.

  i It is understood that one can, without departing from the scope of the invention, imagine other variants and improvements of detail and even consider the use of

equivalent means.

Claims (9)

  1. Electrical switch device comprising several power poles (L1, L2, L3) and an electromagnet for controlling the poles provided with a fixed part and a mobile part (10, 10 '), each pole comprising: - a push-button (20,20 ') cooperating with the mobile part (10,10') of the electromagnet, - a contact closing spring (23) and - a contact bridge (30) which is mobile, under the effect of pusher (20,20 ') and the closing spring (23) of the pole, between an open position and a closed position, characterized in that each pole comprises an opening spring (22) acting in opposition to the closing spring (23) of the pole and whose strength   pressure is greater than the force of the pole closing spring (23).   2. Switching device according to claim 1, characterized in that the opening spring (22) of a pole bears on one side on the pusher (20) of the pole and on the other opposite side on a first face (35) of the movable bridge (30) of the pole,   favoring an opening movement of the movable bridge (30).   3. Switching device according to claim 2, characterized in that the closing spring (23) of a pole bears on one side on a fixed base (12) of the switching device and on the other side opposite on a second face (36) of the movable bridge (30) of the pole opposite to the first face (35), favoring a movement of closing of the movable bridge (30).   4. Switching device according to claim 3, characterized in that the pusher (20) of a pole comprises a transverse recess (25) making it possible to slide the pusher (20) of the pole by a predetermined stroke (D) report to the mobile bridge (30) of the pole.   5. Switching device according to claim 2, characterized in that one end of the opening spring (22) of a pole is positioned and held in   a central cavity (24) of the pusher (20) of the pole.   6. Switching device according to claim 1, characterized in that the opening spring (22) of a pole bears on one side on the movable part (10 ') of the electromagnet of the switching device and the other opposite side on one face (26 ') of the pusher (20'), located opposite the mobile part (10 ') of the electromagnet, between the mobile bridge (30) and the mobile part (10') of the electromagnet, favoring a   opening movement of the movable bridge (30).   7. Switching device according to claim 6, characterized in that the closing spring (23) of a pole bears on one side on a second end of the pole plunger and on the other opposite side on the movable bridge ( 30) of the pole,   promoting a closing movement of the movable bridge (30).   8. Switching device according to claim 7, characterized in that the pusher (20 ') of a pole has at least one flange (21') capable, during a movement of closing of the pole, to come into abutment against at least a corresponding retaining lug (13 '), positioned on the movable part (10') of 1 5 the electromagnet.   9. Switching device according to claim 6, characterized in that one end of the opening spring (22) of a pole is positioned and held in   a central cavity of the pusher (20 ') of the pole.