EP0373018B1 - Hand-operating mechanism for quick break for electric circuit breaker - Google Patents

Description

• une biellette articulée par l'une de ses extrémités sur le bras de contact mobile,
• un organe de commande déplaçable sous l'action d'un organe de manoeuvre manuelle entre une position d'ouverture des contacts et une position de fermeture et inversement, et actionnant la biellette par suite d'une manoeuvre manuelle dans le sens de l'ouverture ou de la fermeture des contacts,
• un ressort accumulateur d'énergie coopérant avec l'autre extrémité de la biellette et sollicitant celle-ci de façon qu'à la suite d'une manoeuvre dans le sens de l'ouverture des contacts, un déplacement de l'organe de commande provoque d'abord, par le passage d'un premier point mort, un basculement de la biellette en assurant un maintien du bras de contact mobile en position de fermeture.

The present invention relates to a manual snap-action control mechanism for the opening and closing of two respectively fixed and movable contacts of an electric switch, the movable contact being carried by a contact arm rocking around a fixed axis, of the type comprising:

• a link articulated by one of its ends on the movable contact arm,
• a control member displaceable under the action of a manual operating member between a contact open position and a closed position and vice versa, and actuating the rod as a result of manual operation in the opening direction or closing contacts,
• an energy accumulator spring cooperating with the other end of the link and urging it so that, following an operation in the opening direction of the contacts, a displacement of the control member causes first, by passing a first dead center, tilting the link ensuring that the movable contact arm is held in the closed position.

Such a snap mechanism used for manual control of an electric switch is known from patent FR-A-1 453 416.

For the opening operation of the contacts of an electric switch, this mechanism involves a neutral point passage using an energy storage spring, a passage which causes the rod to tilt while holding firmly the movable contact arm on the fixed contact, followed by an abrupt tilting of the movable contact arm to its open position. This mechanism is therefore particularly well suited for manual control of the opening of an electric switch because it allows, during the movement of the control member, to maintain the contact pressure almost constant until the abrupt opening. contacts.

As for the operation of closing the switch contacts using the snap mechanism described in the aforementioned patent, it is carried out in the opposite direction, in a manner identical to the opening operation. This mechanism is however unsuitable for manual control of the closing of an electric switch for which a relatively large cutting distance is provided, because in this case, a sudden tilting of the movable contact arm in its closed position may cause the known phenomenon of contact rebound, with all the unfavorable consequences that result from it.

To avoid this phenomenon of contact rebound, it is known that other manual control mechanisms cause a displacement of the movable contact arm first on a first part of the predefined travel course called slow approach - dependent on the operator - between its open position and a position in which it is at a short distance from the fixed contact, then on a second part of the stroke, therefore weak, called abrupt closure of the contacts at during which the actuating force and the speed of the movable contact arm do not depend on the operator. However, during a manual opening control, these mechanisms do not maintain an almost constant contact pressure until the abrupt opening of the contacts.

The present invention therefore aims to design the same manual control mechanism with snap for electric switch, of the type described above, which allows both to maintain the contact pressure almost constant until the abrupt opening of the contacts and make a slow approach before the abrupt closing of the contacts, in a simple way and using the same energy storage spring.

According to the invention, a manual control mechanism with sudden break of the type described above is characterized in that said displacement of the control member then causes and always in the same direction of operation, by passing a second dead center , a sudden opening of the movable contact arm and in that the link carries a drive finger engaged in a clearance light formed in the control member, said clearance light coming to cooperate by pressing with the finger during a displacement of the control member so as to exert on the finger, either a traction following a manual operation in the direction of the opening of the contacts in order to drive the link towards the passage of said first dead center, or a thrust following to manual operation in the direction of closing the contacts, so that a drive of the link by the finger in the direction of closing the contacts first causes a tilt Lement progressive movement of the movable contact arm to approach the fixed contact, then by the passage of said first dead center abrupt closure of the movable contact arm.

• le bras de contact mobile présente la forme d'un U dont les deux extrémités libres sont traversées par un même axe définissant l'axe de basculement du bras et dont l'aile centrale présente en son milieu une avancée dirigée vers l'extérieur du U et portant le contact mobile,
• la biellette présente également la forme d'un U disposé en inclinaison transversalement entre les deux ailes latérales du bras de contact mobile en U et attelé en extrémité à chacune desdites ailes latérales au moyen d'un axe d'articulation respectif parallèle audit axe de basculement du bras de contact, en étant maintenu en équilibre stable au moyen du ressort accumulateur d'énergie accroché en soutien sur la branche centrale de la biellette en U,
• le doigt d'entraînement est monté d'équerre sur la face externe de l'une des deux branches latérales de la biellette et vient en engagement dans la lumière de l'organe de commande en passant par-dessus l'aile latérale correspondante du bras de contact mobile.

According to a preferred embodiment of the invention:

• the movable contact arm has the shape of a U whose two free ends are crossed by the same axis defining the axis of tilting of the arm and whose central wing has in its middle an projection directed towards the outside of the U and carrying the mobile contact,
• the link also has the shape of a U arranged in transverse inclination between the two lateral wings of the U-shaped movable contact arm and coupled at the end to each of said lateral wings by means of a respective articulation axis parallel to said tilting axis the contact arm, while being kept in stable equilibrium by means of the energy accumulator spring hooked in support on the central branch of the U-link,
• the drive finger is mounted at right angles to the external face of one of the two lateral branches of the link and comes into engagement in the lumen of the control member passing over the corresponding lateral wing of the arm of mobile contact.

Advantageously, the energy storage spring is a tension spring, the end opposite to that cooperating with the rod is anchored on a fixed axis parallel to the tilting axis of the movable contact arm.

• Les figures 1 à 5 représent en élévation un mécanisme de commande à rupture brusque conforme à l'invention pour interrupteur électrique, respectivement dans les positions :
  • . de fermeture des contacts lorsque le bouton de manoeuvre occupe la position marche (figure 1),
  • . de premier (figure 2) et de second (figure 3) point mort lorsqu'on tourne le bouton de marche vers arrêt,
  • . d'ouverture des contacts lorsque le bouton occupe la position arrêt (figure 4),
  • . de premier point mort lorsqu'on tourne le bouton d'arrêt vers marche (figure 5) ;
• La figure 6 est une vue en perspective du mécanisme associé au bras de contact mobile ;
• La figure 7 est une vue de face de l'interrupteur électrique à commander, en version tripolaire.

Other characteristics and advantages of the invention will appear more clearly in the detailed description which follows and refers to the appended drawings given solely by way of example and in which:

• FIGS. 1 to 5 show in elevation a snap-action control mechanism according to the invention for an electrical switch, respectively in the positions:
  • . closing the contacts when the operating button is in the on position (Figure 1),
  • . first (figure 2) and second (figure 3) neutral when the on / off button is turned,
  • . opening of the contacts when the button occupies the off position (Figure 4),
  • . first neutral when the stop button is turned to on (Figure 5);
• Figure 6 is a perspective view of the mechanism associated with the movable contact arm;
• Figure 7 is a front view of the electrical switch to be controlled, in three-pole version.

In what follows, the snap-action control mechanism according to the invention will be described in relation to an electrical switch device with a single pole, it being understood that in the case of a multipole switch device, the housing thereof houses as many snap mechanisms as there are poles; for this multipolar version, we will specify how the manual control of the various poles of the device is carried out.

In an exemplary embodiment illustrated in Figures 1 to 5, the snap mechanism is designated by the general reference 10 and is used for manual control of a single-pole switch comprising an insulating housing 12 in which are housed a fixed contact 13 and a movable contact 14 carried by one end of a contact arm 15, which arm 15 is pivotally mounted at its end opposite to the movable contact 14 on a fixed axis 17 integral with the housing 12.

In this example, as shown in FIG. 6, the movable contact arm 15 has the general shape of a U, the central wing 15a of which carries in its middle a projection or projection forming a finger 15b coming in one piece with the U and carrying at the end the movable contact 14, and the two lateral wings 15c, 15d of which are crossed at the end by the same fixed axis 17 constituting the pivot axis of the contact arm 15.

The snap mechanism 10 comprises a link 19 which also has, in this example, FIG. 6, the general shape of a U which is arranged transversely between the two lateral wings 15c, 15d of the U-shaped contact arm, 15, and which is articulated by its two free ends on the two lateral wings 15c, 15d of the contact arm 15, on the side of the central wing 15a of the latter, respectively by means of two axes of articulation, only one of which is visible at 20 in FIG. 6, arranged parallel to the fixed axis 17 of the contact arm 15.

On the central branch 19a of the U-shaped link, 19, FIG. 6, is hung a tension spring 22 whose opposite end is anchored to a fixed axis 23 integral with the housing 12, parallel to the axis 17 and disposed nearby of the fixed contact 13, as shown in FIGS. 1 to 5.

In the embodiment shown in Figures 1 to 5, a manual operating button 25 located outside the housing 12 is pivotally mounted about an axis 26 perpendicular to the axis 17 and cooperates with a control rocker 28 pivotally mounted on a bearing 29 with an axis 30 parallel to the axis 17. A suitable mechanical connection with meshing and / or cam makes it possible to transform the rotary movement of the button 25 into a correlative rotary movement of the rocker 28.

In this example, Figure 6, the rocker 28 is formed by a shaft of axis 30 extending below the two lateral wings 15c, 15d of the contact arm 15 and surmounted by an annular sector 32 extending backwards of the lateral wing 15d of said arm and having an imprint with two notches 32a, 32b intended to cooperate with a connecting piece 34 carrying tenons 34a, 34b (FIGS. 1 to 5); the part 34 is capable of rotating around the axis 26 in response to the pivoting of the button 25 and it has, for this purpose, a square 34c cooperating with a recess provided in the button 25.

As shown in Figure 6, the rocker 28 has a clearance light 36 in which is engaged a drive finger 38, for example cylindrical, which is mounted square on the outer face of the side branch of the connecting rod 19 adjacent at wing 15d, above the latter.

In the closed position of the contacts, illustrated in FIG. 1, the articulated link 19 is kept slightly inclined in a high position of stable equilibrium with respect to the contact arm 15 by means of the tension spring 22; in this Figure 1, there is shown in D the line of action of the spring 22, and in D 'the line passing through the points 19a, 20, these two lines D, D' forming an acute angle oriented downwards.

The drive finger 38 is, moreover, disposed on the link 19 so as to be in abutment against the movable contact arm 15 in the closed position, shown in FIG. 1; in this position, all the energy of the spring 22 is therefore transmitted via the finger 38 to the contact arm 15, which makes it possible to apply the desired contact pressure and to keep it even in the event of wear of the contacts .

In the closed position of the contacts, FIG. 1, the button 25, capable of rotation about the axis 26, occupies the on position (denoted "1" in FIG. 7) and cooperates via the connecting piece. 34 with studs 34a, 34b with the indentation 32a, 32b of the rocker 28.

To pass from the closed position to the open position of the contacts, the operator turns the button 25 around the axis 26 to bring it from the on position to the off position (denoted "0" in FIG. 7). ). The rotation of the button 25 is then 90 ° but can, of course, take place at a different angle.

The rotation of the button 25 from "1" to "0" determines the rotation around the axis 26 of the connecting piece 34 whose tenon 34a engages in the notch 32a of the imprint of the rocker 28. It results in a counterclockwise pivoting of the rocker 28 around the axis 30.

During this pivoting of the rocker 28, in a first stage, the light 36 of the latter is shaped so as to come to cooperate by pressing with the drive finger 38 of the rod 19 in order to exert traction on the finger 38 tending to drive the rod 19 counterclockwise; the line of action of the spring 22 then moves to cross a first dead center corresponding to the alignment of the points 19a, 20, 23, as illustrated in FIG. 2.

In this neutral position, FIG. 2, the movable contact arm 15 remains applied to the fixed contact 13, so that the contact pressure is maintained; strictly speaking, it has somewhat decreased but remains perfectly suitable.

After passing this first dead center, in a second stage, the articulated link 19 suddenly switches between the two lateral wings 15c, 15d (FIG. 6) of the contact arm 15 and the line of action of the spring 22 then crosses a second point death corresponding to the alignment of points 17, 19a, 23 as illustrated in FIG. 3; at the time of crossing this second dead center, the spring 22 acts on the movable contact arm 15 which then suddenly switches counterclockwise to the open position, shown in FIG. 4.

At the end of counterclockwise pivoting of the rocker 28, the rocking of the link 19 is limited by the stop of its finger 38 against one end of the light 36 of the rocker 28, while the opening of the movable contact arm 15 is limited by a stop fixed 39 associated with the housing 12; in FIG. 4, the sectioning distance is indicated by d separating the contacts 13, 14. As seen in Figure 4, the rod 19 now occupies a low position vis-à-vis the contact arm 15 in the open position.

From the open position illustrated in FIG. 4, the operation of closing the contacts by manual operation is carried out by a clockwise rotation of the button 25 from "0" to "1" causing, via the connecting piece 34 , a clockwise pivoting of the rocker 28.

During its pivoting, the rocker 28 exerts on the drive finger 38 cooperating by pressing with the light 36 of the rocker, a thrust causing a clockwise movement of the articulated link 19. As a result of its movement under the action of the rocker 28, the rod 19 causes a progressive pivoting in the same direction of the movable contact arm 15 in such a way that the latter is brought closer to the fixed contact 13 when the line of action of the energy accumulator spring 22 crosses the first dead center corresponding to the alignment of points 19a, 20, 23, as illustrated in Figure 5. When crossing this dead center, Figure 5, the energy released by the spring 22 causes, via the link articulated 19, a sudden tilting of the movable contact arm 15 in the closed position (Figure 1), and this, over a short distance. In FIG. 5, the term "slow approach" for the movable contact arm 15 is indicated by d, the movable contact 14 being shown in phantom in its initial opening position, and by d˝ the closing stroke. sudden contact arm 15.

Thus, the contact closure operation consists of a slow approach to the mobile contact which is dependent on the operator, followed by a sudden closure which is independent of the operator and which takes place on a short distance, thus preventing the occurrence of the contact bounce phenomenon.

In a multipolar version of the switch, the manual control of the contact arms 15 of the various poles is carried out from the button 25 on as many rockers 28 as there are poles, the rockers being coupled together.

Claims (5)

1. A quick-break manual control mechanism for the opening and closing of two respectively fixed (13) and mobile (14) contacts of an electric switch, the mobile contact (14) being borne by a contact arm (15) swinging about a fixed axis (17), of the type comprising:

   - a connecting rod (19) articulated by one of its ends on the mobile contact arm (15),

   - a control device (28) that can be displaced under the action of a manual manoeuvering device (25) between an open position of said contacts and a closed position and vice versa, and activating said connecting rod (19) subsequent to a manual manoeuver in the direction of the closing or opening of said contacts,

   - an energy storing spring (22) cooperating with the other end of said connecting rod (19) and stressing the latter in such a way that, subsequent to a manual manoeuver in the direction of opening of said contacts, a displacement of said control device (28) firstly causes, by the passing of a first dead point, a swinging of said connecting rod (19) ensuring that said mobile contact arm (15) is maintained in the closed position,

   characterized in that said displacement of said control device (28) then causes, and always in the same manoeuvering direction, by the passing of a second dead point, a quick opening of said mobile contact arm (15), and in that said connecting rod (19) bears a drive finger (38) engaged in a clearance slot (36) arranged in said control device (28), said clearance slot cooperating by resting with said finger (38) during displacement of the control device so as to exert on said finger, either a traction subsequent to a manual manoeuver in the direction of opening of said contacts so as to drive said connecting rod (19) towards the passing of said dead point, or a thrust subsequent to a manual manoeuver in the direction of closure of said contacts, so that a driving of said connecting rod (19) by said finger (38) in the direction of closing of said contacts (13, 14) causes firstly a a gradual swinging of said mobile contact arm (15) aimed at approaching it to said fixed contact (13), then by the passing of said first dead point a quick closing of said mobile contact arm (15).
2. The control mechanism as claimed in claim 1,
   characterized in that said energy storing spring (22) is a draw spring of which the end opposite the one cooperating with said connecting rod (19) is anchored to a fixed axis (23) parallel to the swinging axis (17) of said mobile contact arm.
3. The control mechanism as claimed in either claim 1 or 2,
   characterized in that said mobile contact arm (15) is in the shape of a U of which the two free ends are passed through by a same axis (17) defining the swinging axis of said arm and of which the central wing (15a) has in its middle a protruding part (15b) pointed towards the exterior of the U and bearing said mobile contact (14), and in that said connecting rod (19) is also in the shape of a U arranged sloping transversely between the two lateral wings (15c, 15d) of said U-shaped mobile contact arm and coupled at the end to each of said lateral wings (15c, 15d) by means of a respective axis of articulation (20) parallel to said swinging axis (17) of said contact arm (15) while being maintained in stable equilibrium by means of the spring (22) hooked in support to the central branch (19a) of said U-shaped connecting rod (19), said drive finger (38) being mounted square on the outer side of one of the two lateral branches of said connecting rod (19) and engaging in the slot (36) of said control device (28) by passing over the corresponding lateral wing of said mobile contact arm.
4. The control mechanism as claimed in claim 3, characterized in that said drive finger (38) is disposed on one of said lateral branches of said U-shaped connecting rod (19) in a place such that, at the end of the closing operation, it abuts against the corresponding lateral wing of said mobile contact arm (15).
5. The control mechanism as claimed in any one of the previous claims,
   characterized in that said control device (28) is a tipper mounted pivotably on a bearing (29) of axis (30) parallel to the swinging axis (17) of said mobile contact arm (15).

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