FR2823370A1 - Electromagnetic trigger with movable armature and fixed yoke has armature guide part and latching arrangement ensuring rigid attachment of guide part to the yoke - Google Patents

Abstract

The device has an electromagnetic circuit with a fixed yoke (6) and a movable armature (7) with 2 stable equilibrium positions, i.e. a working position in contact with the yoke for closing the electromagnetic circuit and a rest position separate from the yoke for opening the circuit. A latching arrangement latches an armature guide part to the yoke. The shape of the guide part and latching arrangement ensures rigid attachment of guide part to yoke.

Description

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 The invention relates to an electromagnetic trip device comprising an electromagnetic circuit comprising a fixed armature as well as a movable armature capable of occupying two positions of stable equilibrium, namely a working position in which it is pressed against the fixed armature and closes the electromagnetic circuit, and a rest position in which it is separated from the fixed armature and opens the electromagnetic circuit, the movable armature being guided by a part fixed to the fixed armature.

 An electromagnetic trip device of this type is known from document FR-A-2 620 264, from which it appears that the guide part of the movable frame is riveted to the fixed frame.

 This results in a number of drawbacks. It is indeed necessary to pierce the fixed armature, which is delicate because it disturbs the path of the magnetic flux in the circuit. Furthermore, the riveting operation can deform the fixed armature, or generate mechanical stresses in the circuit and cause a phenomenon of magnetostriction which is opposed to the free circulation of the magnetic flux in the circuit, while it is difficult to obtain a precise positioning of the guide piece relative to the fixed frame.

 All in all, the assembly of the trigger proves to be complex and delicate to implement.

 The invention aims in particular to solve the aforementioned drawbacks by proposing an electromagnetic trip device of simple and economical design and assembly, which is at the same time reliable, precise and durable.

 To this end, the invention provides an electromagnetic trip device of the type mentioned in the introduction, characterized in that it includes means for snapping said guide piece onto said fixed frame, the conformation of said guide piece and said means. latching relative to the fixed frame being able, by itself, to allow rigid attachment of said guide piece to said fixed frame.

 In this way, mounting the trigger is limited to a succession of simple operations which can be carried out quickly, in particular automatically. The relative positioning of the constituent parts of the

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 trigger is precise and durable, which contributes to its reliability and increases its lifespan.

 According to a preferred embodiment, said latching means are integrated into said guide piece to form therewith a one-piece assembly.

 The number of constituent parts of the trigger is thus limited.

 The movable frame is for example in the form of a pallet pivotally mounted relative to said guide piece.

 According to other non-limiting preferential characteristics: - said guide piece is in the form of a plate fixed to a branch of the fixed frame, said plate comprising a body, attached to said branch, of which two arms projecting frame the frame and carry elastically flexible teeth each having a bearing surface looking towards the body of the plate, said branch being trapped, in the latched position, between the body of said plate and the bearing surface of said teeth; the fixed frame comprises a base connected to said branch, the frame has ears projecting from said branch, the arms of the plate being caught between said base and said ears; - The arms have bumps which, in the latched position, bear against the ears of the fixed frame; - Said arms are flexible in an elastic manner, and each have a boss at the level of which a cutout is formed forming said tooth.

 In addition, the body of said plate has an elastically flexible tongue which, in the absence of stress, is inclined relative to the body towards said teeth, said branch being clamped, in the latched position, between said teeth and said tongue.

 In this way, the attachment of the wafer and the fixed frame is rigid, while being simple and quick.

 According to yet other characteristics: - said plate includes tabs which project from the body and project beyond the frame, against which beveled parts of the movable frame come to bear, around which the latter is articulated;

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- l'armature mobile comporte une partie dépassant desdites parties biseautées, qui se trouve, en étant libre de mouvement, entre les pattes, et dans laquelle est pratiqué un trou traversant dans lequel est ancré par une extrémité un ressort de rappel sollicitant l'armature mobile vers sa position de repos, le ressort de rappel étant ancré par une autre extrémité sur une patte de la plaquette ; l'armature fixe est en forme de U, et comporte une première et une deuxième branches reliées par une base, ladite plaquette étant fixée à ladite deuxième branche ; le déclencheur comporte un boîtier dans lequel est disposé le circuit électromagnétique, ledit boîtier comportant un socle coiffé d'un couvercle, socle sur lequel repose l'armature fixe ; - l'armature fixe est assujettie audit boîtier, sa base étant serrée entre le socle et le couvercle.

- The movable frame comprises a part projecting from said bevelled parts, which is, being free of movement, between the tabs, and in which a through hole is made in which an end is anchored by a return spring urging the frame movable to its rest position, the return spring being anchored by another end on a tab of the plate; the fixed frame is U-shaped, and comprises first and second branches connected by a base, said plate being fixed to said second branch; the trip device comprises a housing in which the electromagnetic circuit is disposed, said housing comprising a base capped with a cover, base on which the fixed frame rests; - The fixed frame is subject to said housing, its base being clamped between the base and the cover.

 Other characteristics and advantages of the invention will appear in the light of the following description of an embodiment given by way of nonlimiting example, description made with reference to the appended drawings in which: - Figure 1 is a perspective view of an electromagnetic trip device according to the invention; - Figure 2 is a sectional view of longitudinal elevation along the section plane II-II of Figure 1; - Figure 3 is a cross-sectional elevation view partially along the line Illa-Illa, and partially along the line Illb-Illb of Figure 2; - Figure 4 is a plan elevation view of the electromagnetic trip device of the previous figures, without its cover, shown in a first stable equilibrium position of the movable frame; - Figure 5 is a view similar to Figure 4, in a second stable equilibrium position of the movable frame; - Figure 6 is a view similar to Figures 4 and 5, in a third stable equilibrium position of the movable frame;

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- Figure 7 is a top plan view of the electromagnetic trip device of Figure 6; - Figure 8 is a sectional view of longitudinal elevation along the line VIII-VIII of Figure 7; - Figure 9 is a perspective view of the electromagnetic trip device of the previous figures, devoid of its base and its cover as well as the coil winding, in the position of Figure 4; - Figure 10 is a perspective view of the electromagnetic trigger of Figure 9, from another angle of view; - Figure 11 is a top plan view of the movable frame of a trip device according to the invention; - Figure 12 is a longitudinal elevation plan view of the movable frame of Figure 11; - Figure 13 is a perspective view of a guide piece of the movable frame of an electromagnetic trip device according to the invention; - Figure 14 is a longitudinal elevation plan view of the guide piece of Figure 13; - Figure 15 is a top plan view of the guide part of Figure
13; - Figure 16 is a longitudinal elevation plan view of the fixed frame of an electromagnetic trip device according to the invention; - Figure 17 is a transverse elevation plan view of the fixed frame of Figure 16; - Figure 18 is a perspective view of the base of the electromagnetic trip device of Figures 1 to 8; - Figure 19 is a top plan view of the base of Figure 18; - Figure 20 is a sectional view of longitudinal elevation of the base of Figures 18 and 19, along the line XX-XX of Figure 19; - Figure 21 is a sectional view of longitudinal elevation of the cover of the electromagnetic trip device of Figure 2, shown alone; - Figure 22 is a longitudinal elevation plan view of the carcass of the coil of an electromagnetic trip device according to the invention;

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- la figure 23 est une vue en plan de dessous de la carcasse de la figure 22 ; - la figure 24 est une vue en coupe d'élévation longitudinale de la bobine du déclencheur électromagnétique des figures 1 à 8, selon la ligne XXIV-XXIV de la figure 7 ; - la figure 25 est une vue en plan d'un picot entrant dans la réalisation de la bobine de la figure 24.

- Figure 23 is a bottom plan view of the carcass of Figure 22; - Figure 24 is a sectional view of longitudinal elevation of the coil of the electromagnetic trip device of Figures 1 to 8, along the line XXIV-XXIV of Figure 7; FIG. 25 is a plan view of a pin used in the production of the coil of FIG. 24.

 In Figures 1 to 3 is shown an electromagnetic trip device 1 with high sensitivity for a switch or a circuit breaker, which comprises, in a housing 2 assumed to be fixed, composed of a base 3 capped with a cover 4, an electromagnetic circuit 5 comprising a fixed U-shaped armature 6, secured to the housing 2 as well as a movable armature 7 called a pallet, capable of pivoting to open or close the electromagnetic circuit 5.

 In FIGS. 1 to 3 is also shown a reference constituted by three orthogonal directions, namely: - a longitudinal direction L oriented from a location called rear towards an opposite location called front; - a transverse direction T; and - a direction E of elevation, oriented from a location called low or lower to an opposite location called high or higher.

For reasons of convenience, the trigger 1 is described with respect to this reference, according to the orientation adopted in FIG. 2, which corresponds to the most common use of the trigger 1.

In all that follows, the terms front, rear, bottom, top, bottom, top are used with reference to the directions which have just been defined.

 The fixed frame 6 and the pallet 7 are both made of a ferromagnetic material, such as an Iron-Nickel alloy.

 The fixed frame 6 comprises a first branch 8 called the front and a second branch 9 called the rear, connected by a base 10 resting on the base 3 of the housing 2.

 The electromagnetic circuit 5 comprises a coil 11 comprising a carcass 12 on which a coil 13 is wound, the carcass 12 being threaded on the front branch 8 of the fixed frame 6 and secured to the base 3.

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 Between the branches 8, 9 is interposed a permanent magnet 14 for the magnetic polarization of the fixed frame 6. The magnet 14, of parallelepiped shape, is fixed by one of its ends to the base 10 of the fixed frame 6, preferably by welding. More specifically, the magnet 14 is fixed on an upper face 15 of the base 10, which also has an opposite lower face 16.

 The pallet 7 is capable of occupying at least two stable equilibrium positions, namely a working or engaged position, in which it is pressed against the branches 8, 9 of the fixed frame 6 and closes the electromagnetic circuit 5 , and a rest or triggered position, in which it is moved away from the fixed armature 6 and opens the electromagnetic circuit 5.

 The pallet 7 is biased towards its position triggered by a return spring 17 operating in traction.

 When the coil 11 is not excited, the pallet 7 is held in the engaged position against its return spring 17 by the force of attraction of the permanent magnet 14.

 The excitation of the coil 11 releases the pallet 7 from the action of the magnet 14, the latter then pivoting towards its triggered position, under the action of the return spring 17.

 The pallet 7 has two opposite parallel flat faces, namely an upper face 18 and a lower face 19.

 The respective free ends 20, 21 of the front 8 and rear 9 branches form polarization surfaces situated substantially in the same plane of polarization P, with which the lower face 19 of the pallet 7 cooperates in the engaged position.

 The pallet 7 has the shape of a trident and has a body 22 of rectangular shape with two side wings 23, 24 bent backwards, and whose rear edges 25 are bevelled to form knives 26 for the articulation of palette 7.

 Each knife 26 has an inclined face 27 turned upwards, terminated downwards by an edge 28 situated substantially in the plane of the lower face 19 of the pallet 7. The edges 28 together form an axis A of pivoting of the pallet 7 .

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 On the rear branch 9, which has an opposite front face 29 and a rear face 30, is fixed by snap-fastening a plate 31 ensuring the guiding of the pallet 7, the latter being pivotally mounted relative to the plate 31.

 This plate 31 is a single piece made for example from a metallic material for the purpose of rigidity. It comprises a body 32 pressed against the rear face 30 of the rear branch 9, which it substantially covers. This body 32 is extended upwards, in the form of a fork, by two similar upper legs 33,34 which protrude from the fixed frame 6 projecting from the plane of polarization P, arranged opposite the wings 23,24 of the pallet 7, and against which the knives 26 are applied.

 More precisely, each tab 33, 34 has a front face 35 of support against which is applied, under the action of the return spring 17, the edge 28 of the knife, 26 in the engaged position (FIG. 4).

 In the triggered position, the pallet 7 is in linear contact, through its body 22, with the rear branch 9, the lower face 19 of the pallet 7 being supported on a rear edge 36 of the free end 21 of the rear branch 9 (figure 5).

 Furthermore, the pallet 7 has, at the level of its wings 23, 24, a transverse extension greater than that of the rear branch 9, the knives 26 being permanently spaced laterally from the latter.

 The knives 26 never being in contact with the rear branch 9, they do not produce, during possible wear, any particle capable of being deposited on the polarization surface 20, 21.

 As a result, the air gap between the pallet 7 and the fixed frame 6 is kept substantially constant. The efficiency, speed and lifespan of trigger 1 are increased.

 The pallet 7 has rearwardly a tail 37 which extends beyond the wings 23,24 projecting from them, which is, being free to move, between the legs 33,34 of the plate 31 , and in which one of the upper ends 38 of the return spring 17 is anchored.

 This upper end 38 of the return spring 17 forms a loop inserted into a through hole 39 made in the tail 37, beyond the edges 28 towards the rear, so as to form a cantilever allowing the

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 pivoting of the pallet 7, under the action of the spring 17, around the axis A formed by its edges 28.

 The plate 31 ends downwards with a lower tab 40 folded back, in which the other lower end 41 of the return spring 17 is anchored.

 The upper legs 33, 34 are each extended upwards by a bent extension 42 forming a hook defining a housing 43 capable of receiving the pallet 7.

 The hook 42 comprises, towards the rear, an inclined bottom 44 connected to the tab 33, 34 by a part 45 folded back at right angles to the tab 33, 34, and, upwards, a return 46 folded at right angles to the bottom 44.

 The bottom 44 has a bearing surface 47 facing forward and upward, while the return 46 has a bearing surface 48 facing the fixed frame 6, that is to say towards the forward and down.

 The pallet 7 is capable of occupying a third stable equilibrium position, called lifted, in which it is inclined and is spaced from the fixed frame 6 beyond the rest position, and in which it cooperates with the hook 42 being received in the housing 43 (Figures 6,7, 8).

 The tail 37 of the pallet 7 has, towards the rear, an end portion 49 of reduced transverse extension delimited towards the front by two lateral recesses 50, 51 forming stops.

 In the raised position of the pallet 7, these stops 51.52 are applied against the bearing surface 47 of the bottom 44 of the hook 42 with the end part 49 inserted between the bottoms 44 of the hooks 42 facing each other, while the face upper 18 of the pallet 7 is applied against the bearing surface 48 of the return 46 of the hook 42.

 In this raised position, the pallet 7 is spaced from each of the branches 8, 9 of the fixed frame 6, as it appears in FIGS. 6 and 8.

 The pallet 7 can be moved to its raised position from its triggered position under the action, for example, of an automated gripping device (not shown), which grips the pallet 7 in the triggered position then, pulling

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 on the spring, place the pallet 7 in the raised position in cooperation with the housing 43.

 Conversely, the pallet 7 can be restored in the triggered position - or directly in the engaged position - from the raised position, by the same automated gripping device, which, coming to grip the pallet 7, moves it away from the housing 43 by pulling on the spring 17 to then deposit it on the fixed frame 6.

 There is a cantilever between the stops 50.51 and the rear edge of the hole 39, against which the return spring 17 bears, so that the action of the latter is sufficient to keep the pallet 7 in balance stable in its raised position.

 Moreover, in order to increase the stability of this balance, the spring 17 is inclined slightly backwards, from the top to the bottom.

 In this position, it is possible to access the electromagnetic circuit to carry out its cleaning in order to rid it, particularly at the level of the polar surfaces 20, 21 of the branches 8, 9 and of the lower face 19 of the pallet 7, of any impurity likely to halt the subsequent proper functioning of the trigger 1, in particular by modifying the air gap between the pallet 7 and the fixed frame 6.

 This cleaning, which takes place in particular when the trigger 1 is mounted, can be carried out by ultrasound, by spraying, in particular by cryogenic spraying such as a jet of carbon dioxide, or by any other equivalent process known to those skilled in the art.

 It should be noted that, in this raised position, the knives 26 are free, spaced from the hooks 42, and protected from any impact liable to damage them (FIG. 6).

 The parts 45 of the hooks 42 folded backwards each have a recess 52 towards the inside, which the pallet 7 bypasses during its passage from the triggered position to the raised position, before coming to press against the bottom 44 of the hook 42 .

 Furthermore, in order to secure the plate 31 to the rear branch 9, the plate 31 has, in its lower part, latching means integrated in the form of two arms 54, 55 projecting from the body 32 in its part lower, come of matter with him and folded in square towards

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 the front, and which surround the rear branch 9 near the base 10 of the fixed frame 6.

 In order to ensure the immobilization of the plate 31 in elevation, the arms 54, 55 are arranged between, on the one hand, upwards, two ears 56, 57 projecting transversely from the rear branch 9 approximately at mid-height of this, and on the other hand, downwards, the base 10 of the fixed frame 6.

 Each arm 54, 55 also has, on its upper edge in the vicinity of the body 32, a boss 53 projecting upwards and which, under the effect of the tension of the spring 17 on the plate 31, is pressed against a lower face of the corresponding ear 56, 57 so as to make up for the games of elevation likely to appear between the plate 31 and the fixed frame 9.

 The arms 54, 55 are flexible in an elastic manner, and each have a boss 58 projecting inwards.

 In each arm 54.55 is produced, at the level of the boss 58, a U or V cut delimiting a tooth 59 which projects from the arm 54.55 towards the body 32 of the plate 31, and has a bearing surface 60 facing back looking at the body 32.

 Given the rigidity of the plate 31, it can be snapped onto the rear branch 9 automatically by a specific machine (not shown), which, for example, beforehand spreads the arms 54, 55 so as not to damage the branch 9.

 In order to ensure a firm hold of the wafer 31 on the rear branch 9, the wafer body 32 has, facing and in line with the teeth 59, a tongue 61 formed by a V-shaped cutout in the wafer body 32 and which , in the absence of stress, is tilted forward.

 The tongue 61 has a certain elasticity so that, in the latched position, the rear branch 9 is clamped between the teeth 59 and this tongue 61.

 The conformation of the plate 31, in particular of the arms 54, 55, with respect to the fixed frame, is thus capable, by itself, of allowing rigid fixing by snap-fastening, of the plate 31 on the fixed frame 6.

 The mounting of the trigger 1 is now described.

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The base 3 and the cover 4 are two monobloc parts each made by molding a synthetic material such as PVC, polypropylene, polyoxymethylene, or equivalent.

The base 3 comprises a bottom wall 62 on which the electromagnetic circuit 5 rests, bordered by two side walls 63, 64 facing each other, whose teeth 65 project outwards for the snap-fastening of the cover 4.

The side walls 63, 64 extend forwardly beyond the bottom wall 62, and the base 3 has, at the front, a through hole 66 of rectangular section, extended from a wall 63 to the other 64.

This hole 66 is bordered forwards by a cross-member 67 forming the front end of the base 3, and towards the rear by a partition 68 which separates it from the bottom wall 62.

The base 3 also has two identical pairs of studs 69, 70 arranged facing one another at each of the junctions between the base 3 and the side walls 63, 64. Each pair comprises a first 69 and a second 70 studs projecting upwards and inwards, at the junction between the side wall 63, 64 and the bottom wall 62.

The first stud 69, located near the partition 68, has transverse and elevation dimensions respectively greater and less than those of the second stud 70.

Each stud 69, 70 is rounded inwards, the studs 69, 70 delimiting together, in line with the bottom wall 62, a reception zone 71 of the base 10 of the fixed frame 6.

The bottom wall 62 has, at the level of the reception zone 71, an elastically deformable zone 72, this zone 72 being more particularly able to sink elastically downwards under the effect of a pressure which would be applied to it. top to bottom.

The base 3 has, near the center of this deformable zone 72, a pin 73 which projects from the bottom wall 62 upwards and has a free end 74 forming a bearing surface located relative to the deformable zone 72.

In order to allow the elastic deformation of the bottom wall 62, this zone 72 is here inscribed in a circle inside which the bottom wall 62

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 has a conical section with a taper facing downwards, the bottom wall 62 tapering from the edge of the said circle towards its center, that is to say in line with the pin 73.

 The cover 4 is in turn a hollow part, of generally parallelepiped shape, having an upper wall 75 bordered by a front wall 76, a rear wall 77, and two side walls 78, 79 which together define, downward, an opening 80 by which the cover 4 is intended to be associated with the base 3.

 Near the opening 80, each side wall 78, 79 has two legs 81 paired in each of which is made a window 82 intended to cooperate with one of the teeth 65 of the base 3 in order to snap on the cover 4.

 In order to promote the bending of the legs 81 and the guiding of the cover 4 when it clicks into place, each side wall 78, 79 has a notch 83 between the legs 81, intended to cooperate with a complementary bead 84 projecting outwards on each side wall 63,64 of the base 3.

 Each side wall 78, 79 of the cover 4 also has an inner surface 85 along which runs a rib 86 projecting inwards, which extends from the upper wall 75 towards the opening 80. This rib 86 has a lower end 87 projecting from the notch 83 downwards, terminated by a surface 88 forming a stop.

 When mounting the trigger 1, the fixed frame 6 is placed on the base 3, its base 10 being placed in the receiving zone 71, which is complementary to it, by being inserted between the pins 69.70 which frame the deformable zone 72 and which, forming shims, limit the longitudinal and possibly transverse movement of the fixed frame 6, the limitation of the transverse movement can also be achieved by the side walls 63, 64.

 The underside 16 of the base rests on the pin 73 while being in contact with the bearing surface 74 thereof, which is of limited area compared to that of the deformable zone 72 in order to concentrate the stresses.

 The latching of the cover 4 on the base 3, with the stop 88 of the rib 86 looking at the deformable zone 72, causes, by the dimensions and the conformation of the base 3, of the cover 4 and of the base 10 of the fixed frame 6

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 the support of this stop 88 against the upper face 15 of the base 10 against the stress of the deformable zone 72.

 The base 10 is then clamped, maintained, immobilized in elevation between the pin 73 and the rib 86, the deformable zone 72 urging, under the effect of its own elasticity, the base 10 towards the cover 4.

 Under the effect of the pressure of the rib 86 against the upper face 15 of the base 10 of the fixed frame 6, the base 10 presses on the pin 73, which causes the deformable zone 72 to sink and, by the elasticity of the latter, the take-up of the games likely to appear between the base 10 of the fixed frame 6, the base 3, and the cover 4, and the precise positioning of the fixed frame 6 relative to the housing 2 .

 In addition, the cover 4 has, on its front 76 and rear 77 walls, two fixing tabs 89.90 perforated or hollowed out in the shape of an ear, making it possible to secure the trigger 1 on a differential protection device (not shown) bistable capable of being actuated by trigger 1.

 To this end, the trigger 1 comprises an actuating device 119 which comprises a pusher 114 inserted in a through hole 115 made in the upper wall 75 of the cover 4, in line with the body 22 of the pallet.

 The pusher 114 comprises an upper end part 116 projecting from the upper wall 75 towards the outside and capable of cooperating with the differential protection device, and a lower end part 117 projecting from this wall 75 towards the inside, and the tip shape or carries a hemispherical head 118 capable of cooperating with the pallet body 22.

 The operation of trigger 1 is briefly described.

 The pallet 7 is assumed to be in its engaged position, the pusher 114 being in a so-called depressed position where the head 118, which is in abutment against the pallet body 22, is at a distance from the wall 75 (FIGS. 2, 3).

 When a current flows through the winding 13, the induced magnetic field disturbs the magnetic field of the permanent magnet 14. This disturbance causes the release of the pallet 7, which pivots under the action of the spring 17 towards its triggered position by driving the push button 114 towards a so-called position

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 ascent (Figure 5) where the upper end portion 116 triggers the differential protection device.

 Under the action of an external mechanical stress applied to the upper extreme part 116, and directed from the top to the bottom, the pusher 114 returns to its depressed position by forcing the pallet 7 to occupy its engaged position.

 It is understood that the precision of the positioning of the pusher 114 relative to the housing 2 depends on the precision of action of the trigger 1, both in the triggered position and in the engaged position.

 In the engaged position, the elevation position of the pusher 114 depends on the elevation positioning of the frames 6,7, that is to say, taking into account the fact that the pallet 7 is caught between the pusher 114 and the frame fixed 6, the positioning of the fixed frame 6 relative to the housing 2. This positioning being precise, as we have seen above, the precision of the positioning of the pusher 114 relative to the housing 2 is therefore ensured.

 Now back to the coil 11 and its carcass 12.

 The carcass 12 comprises a lower flange 91 and an upper flange 92 framing the winding 13, connected by a hollow core 93 threaded on the front branch 8, and having a through hole 94 whose shape is complementary thereto.

 The carcass 12 further comprises a foot 95 of rectangular section which projects from the bottom flange 91, downwards. The carcass 12 is assembled to the base 3 by pressing its foot 95 into the hole 66. The relative dimensions of the foot 95 and the hole 66 are chosen so that, once pressed into the hole 94, the foot 95 is mounted tight in this last, so that the carcass 12, once assembled, is held firmly in a predetermined fixed position.

 The coil 13 can be directly connected to an electrical circuit (not shown) such as an electronic card, however, according to a preferred embodiment, the foot 95 has two through holes 96 in each of which is inserted a metal pin 97 having a protruding lower part 98 intended to be connected to the electrical circuit, as well as an upper part 99

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 protruding intended to be associated with the winding wire 13, for example by welding.

 Before its assembly to the carcass 12, the pin 97 has substantially the shape of a J, its lower part 98 being of transverse dimension greater than that of its upper part 99 (FIG. 25).

 Each pin 97 has, near its center, that is to say at the junction between its lower 98 and upper 99, a recess 100 forming a stop which, when the pin 97 is inserted in the corresponding hole 96 in the leg 95, is applied against a transverse bearing surface 101 formed in hole 96.

 In order to immobilize the pin 97 in the foot 95 to make it integral with the carcass 12, its upper part 99 is folded in Z towards the front.

The upper part 99 has, at a certain distance from the recess 100, a narrowing 102 which, when the upper part 99 is folded, forms the central branch of the Z and is housed in a complementary notch 103 made in the upper surface of the lower flange 91, and adjacent to hole 96.

 The pin 97 is thus immobilized in translation along the direction of elevation.

 The front branch 8 of the fixed frame 6 has an opposite front face 104 and rear face 105, connected by two lateral faces 106, 107. The through hole 94 of the core 93 of the carcass 12 also has a front face 108 and a rear face 109 opposite, connected by two lateral faces 110,111.

The dimensions and the conformation of the base 3, of the fixed frame 6 and of the carcass 12 are chosen so that, once these parts are assembled, there is everywhere a clearance between the front branch 8 and the carcass 12, namely : - a first clearance J1 between the front face 104 of the front branch 8 and the rear face 109 of the hole 94 of the facing core 93; - A second clearance J2 between the rear face 105 of the front branch 8 and the front face 108 of the hole 94 of the facing core 93; - a third J3 and a fourth J4 clearances between the respective lateral faces
106,107, 110,111 of the front branch 8 and the hole 94 of the core 93 opposite.

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 Each set J1, J2, J3, J4 is here predetermined by the shortest chain of dimensions directly connecting the junction surfaces of the fixed frame 6, the base 3 and the carcass 12, starting from a terminal surface formed by a face 104, 105, 106, 107 of the front branch 8 delimiting said clearance, to lead to the face 108, 109, 110, 111 of the hole 94 opposite, forming another end surface defining the same clearance J1, J2, J3, J4.

 Furthermore, the elevation dimension or height of the carcass 12, measured between the non-facing faces of the flanges, that is to say a lower face 112 of the lower flange 91 and an upper face 113 of the upper flange 92, is chosen to be less than the elevation dimension or height of the front branch 8, that is to say the distance separating the upper face 15 from the base 10 from the polarization surface 20.

 Thus, during the mounting of the trigger 1, the foot 95 is inserted into the hole 66 to a predetermined depth, such that, on the one hand, the front branch 8 protrudes from the upper flange 92, the free end 20 of the front branch 8 projecting from the upper face 113 of the upper flange 92, and, on the other hand, the lower face 112 of the lower flange 91 is spaced from the upper face 15 of the base 10 so that there is a clearance J5 between them ( figure 2).

 In this way, the carcass 12 is rigidly mounted relative to the housing, while being mounted floating relative to the fixed frame 6, that is to say spaced therefrom at any point. The fixed frame 6 is thus preserved from the stresses and deformations to which the carcass 12 is subjected, in particular during the mounting of the pins 97 on the aforementioned electrical circuit.

 The invention is in no way limited to the embodiment which has just been described by way of example.

Claims (13)

 CLAIMS 1. Electromagnetic trip device comprising an electromagnetic circuit (5) comprising a fixed armature (6) as well as a movable armature (7) capable of occupying two positions of stable equilibrium, namely a working position in which it is located pressed against the fixed armature (6) and closes the electromagnetic circuit (5), and a rest position in which it is moved away from the fixed armature (6) and opens the electromagnetic circuit (5), the movable armature ( 7) being guided by a part (31) fixed to the fixed frame (6), characterized in that it comprises latching means (54, 55) of said guide part (31) on said fixed frame ( 6), the conformation of said guide piece (31) and said latching means (54, 55) relative to the fixed frame (6) being capable, by itself, of allowing the rigid fixing of said piece of guide (31) to said fixed frame (6).  2. An electromagnetic trip device according to claim 1, characterized in that said latching means (54, 55) are integrated into said guide piece (31) to form therewith a monobloc assembly.  3. Electromagnetic trip device according to claim 1 or 2, characterized in that said movable armature (7) is in the form of a pallet pivotally mounted relative to said guide piece (31).  4. Electromagnetic trip device according to one of claims 1 to 3, characterized in that said guide piece (31) is in the form of a plate fixed to a branch (9) of the fixed frame (6), said plate (31) comprising a body (32), attached to said branch (9), from which project two arms (54,55) which frame the frame (6) and carry elastically flexible teeth (59) each having a surface support (60) looking towards the body (32) of the plate (31), said branch (9) being trapped, in the snapped-in position, between the body (32) of said plate (31) and the surface of support (60) of said teeth (59).  5. An electromagnetic trip device according to claim 4, characterized in that, the fixed armature (6) comprising a base (10) connected to said branch (9), the fixed armature (6) has ears (56,57) protruding from said branch (9), the arms (54,55) of the plate (31) are caught between said base (10) and said ears (56,57). <Desc / Clms Page number 18>  6. An electromagnetic trip device according to claim 5, characterized in that the arms (54, 55) have bumps (53) which, in the latched position, bear against said ears (56, 57).  7. electromagnetic trip device according to one of claims 4 to 6, characterized in that said arms (54,55) are flexible in an elastic manner, and each have a boss (58) at the level of which a cutout forming said tooth is made ( 59).  8. Electromagnetic trip device according to one of claims 4 to 7, characterized in that the body (32) of said plate (31) has an elastically flexible tongue (61) which, in the absence of stress, is inclined relative to to the body (32) towards said teeth (60), said branch (9) being clamped, in the latched position, between said teeth (59) and said tongue (61).  9. Electromagnetic trip device according to one of claims 4 to 8, characterized in that said plate (31) has tabs (33,34) which project from the body (32) and project beyond the frame (6), against which are applied bevelled parts (26) of the movable frame (7), around which the latter is articulated.  10. Electromagnetic trip device according to claim 9, characterized in that the movable armature (7) comprises a part (37) projecting from said bevelled parts (26), which is, being free of movement, between the tabs (33, 34), and in which is made a through hole (39) in which is anchored by one end (38) a return spring (17) urging the movable armature (7) towards its rest position, the return spring ( 17) being anchored by another end (41) on a tab (40) of the plate (31).  11. Electromagnetic trip device according to one of claims 4 to 10, characterized in that the fixed armature (6) is U-shaped, and has first and second branches (8,9) connected by a base (10 ), said plate (31) being fixed to said second branch (9).  12. An electromagnetic trip device according to claim 11, characterized in that it comprises a housing (2) in which the electromagnetic circuit (5) is arranged, said housing (2) comprising a base (3) capped with a cover (4 ), base (3) on which the fixed frame (6) rests. <Desc / Clms Page number 19>  13. An electromagnetic trip device according to claim 12, characterized in that the fixed armature (6) is subject to said housing (2), its base (10) being clamped between the base (3) and the cover (4).