EP0840337B1 - Switch mechanism - Google Patents

Abstract

The inverter mechanism (10) includes three fix contacts (11A,B), connected to two terminals (12A,B), and a conducting brush (13) attached to the input contact (11A). A rocking button actuates the brush which comes in contact with the two output contacts. The terminals have an identical structure which includes a body (16), with a hole (17) engaged by an electrical conductor, and a screw (18) engaging a threaded hole (19) perpendicular to the conductor hole. The mechanism is housed inside a box (20) with a lid (22). The box body presents two lateral tongues (30) which can be used to fix the box inside a recess.

Description

The present invention relates generally switch mechanisms of the kind comprising, on the one hand, at least two fixed contacts, namely, for example, a contact input and at least one output contact, which each respectively, are in electrical connection with two terminals of connection, and, on the other hand, a conductive broom, which is in electrical connection with the input contact, and which, under the control of a control member, is movable between two positions, i.e. a position for which it relates to the output contact, and a position for which it is at otherwise dismissed from it.

For example, it could be a simple switch, in which case only one output contact is provided, the brush conductor then bearing at best only on a simple stud rest when removed from this output contact.

As a variant, it can also be an inverter, back and forth, in which case two output contacts are provided, the conductive broom alternately bearing on one either of these depending on its position.

An output switch mechanism of this kind is found for example described in the French patent which, filed on October 29, 1986 under No. 86 15041, was published under No 2 606 208.

According to one of the embodiments described in this French patent, the conductive broom has two branches lateral in continuity with a middle branch, and it closes in loop on the input contact, being articulated to this input contact at two opposite points thereof.

This provision has given and can still give satisfaction.

But it has drawbacks, which are the following.

First, the joints, and this is in practice of knife-type joints, by which the conductive brush is engaged with the input contact, must perform a dual function, pivoting mounting, and transmission of electric current.

The transmission of electric current by doing this made by simple contact, it is not uncommon to find at this level of untimely heating.

In practice, to improve contact conditions corresponding, it is usual to drown in a mass of grease the affected area, in particular to avoid any oxidation of the metallic elements involved in this area, at price of an additional operation when mounting all.

In addition, the number of separate metal elements to be implemented for the constitution of such a mechanism of switch is relatively important.

Finally, the articulations of the conductive broom are making on a fixed part, in this case the input contact, its support on the output contact is frank, without benefiting from any transverse movement by relative to the axis thereof, neither at closing nor at the opening.

This is all the more so as this conductive broom in practice relates to the output contact by one of its lateral branches, close to the input contact, and that, from this output contact to this input contact, this branch lateral is straight or substantially straight, not possibly bending at its end for its articulation at the input contact.

In Italian Patent No. 468,510, the middle branch of the conductive brush is integral with the input contact, being in practice screwed on it, which normally avoids to have to plan any fat intake in the area corresponding.

But, in this Italian patent, the lateral branches of the conductive broom extend parallel to its branch median, on either side of it, coming in cusp of a crosspiece from which the middle branch also comes back, these side branches are finding for example in engagement, pivoting, in positions diametrically opposite to each other, with a central tilting nut, which, itself swivel mounted under the control of the control unit, is capable of ensuring the passage of the conductive broom from one of its positions to the other.

Besides that the corresponding conductive broom constitutes a relatively complex and bulky room, to the detriment of the compactness of the whole, it cannot, as previously, that bear frankly on the output contact, without be able to be locally the object of any movement transverse to the axis thereof.

In U.S. Patent No. 3,527,913, the branches side of the driver's broom extend freely, without being engaged with a tilting nut.

It is the same in the German patent application No 2,061,974.

The present invention generally has for object a provision which, taking advantage of the implementation a tilting nut advantageously promotes obtaining systematic transverse movement of the conductive broom by contacts, for the benefit of self-cleaning of these contacts in service, and which further leads to other benefits.

More specifically, it relates to a switch mechanism of the kind comprising, on the one hand, at minus two fixed contacts, namely, for example, one contact input and at least one output contact, which each respectively, are in electrical connection with two terminals of connection, and, on the other hand, a conductive brush, which comprises a middle branch, by which it is integral with the contact entry, and two side branches, which in positions diametrically opposed to each other, are in swiveling socket with a central tilting nut, said central tilting nut being itself mounted swiveling under the control of a control member between two positions, i.e. a position for which the broom conductor relates to the output contact, and a position for which on the contrary is removed from it, this mechanism of a switch being generally characterized in that that, the lateral branches of the conductive broom being in continuity with its middle branch, by connecting each with the latter by a largely rounded bend, and said broom conductor being able to carry on the output contact by one of its lateral branches, said output contact is located near the central tilting nut, so that, by said lateral branch, the conductive broom is locally undergoing a self-cleaning transverse movement when it is pressed on said output contact.

Indeed, the lateral branch follows the nut at this level tipping center, and the path thereof circular, it itself follows a path having a component transverse to the axis of the output contact.

There is nothing like that, and there can be nothing like it, neither in either of the two documents succinctly analyzed above.

In addition, in the event of a possible sticking of the broom conductor on the output contact, detachment is advantageously systematically insured; because of the location of the output contact near the nut tilting center, play and elasticity are limited at this level, and they do not allow to activate the control without effectively detaching the brush driver.

In addition, the fact that elasticity plays little role in this level, the conductive brush advantageously applies from abrupt way on the output contact, with a limitation advantageous of its possible rebounds.

la figure 1 est une vue en perspective d'un mécanisme d'interrupteur suivant l'invention ;

la figure 2 est, avec des arrachements locaux, une vue en perspective éclatée de ce mécanisme d'interrupteur ;

la figure 3 est, sous une autre orientation, une vue en perspective du balai conducteur que comporte ce mécanisme d'interrupteur et du contact d'entrée dont est solidaire ce balai conducteur ;

la figure 4 est, suivant la ligne IV-IV de la figure 2, une vue en coupe axiale de la noix centrale de basculement avec laquelle sont en prise à pivotement les branches latérales de ce balai conducteur ;

la figure 5 est, à échelle supérieure, suivant la ligne V-V de la figure 1, une vue en plan-coupe du mécanisme d'interrupteur suivant l'invention, pour l'une des positions de son balai conducteur ;

la figure 6 est une vue en plan-coupe analogue à celle de la figure 5, pour l'autre des positions de ce balai conducteur.

The characteristics and advantages of the invention will become apparent from the description which follows, by way of example, with reference to the appended schematic drawings in which:

Figure 1 is a perspective view of a switch mechanism according to the invention;

Figure 2 is, with local cutaway, an exploded perspective view of this switch mechanism;

Figure 3 is, in another orientation, a perspective view of the conductive brush that includes this switch mechanism and the input contact which is integral with this conductive brush;

Figure 4 is, along the line IV-IV of Figure 2, an axial sectional view of the central tilting nut with which are pivotally engaged the lateral branches of this conductive brush;

Figure 5 is, on a larger scale, along the line VV of Figure 1, a sectional view of the switch mechanism according to the invention, for one of the positions of its conductive brush;

Figure 6 is a sectional plan view similar to that of Figure 5, for the other of the positions of this conductive brush.

As illustrated in these figures, and in a known manner per se, the switch mechanism 10 according to the invention comprises, on the one hand, at least two fixed contacts 11A, 11B, namely, for example, an input contact 11A and at least one output contact 11B, which, respectively, are in electrical connection with two connection terminals 12A, 12B, and, on the other hand, a conductive brush 13, which is in connection electric with input contact 11A, and which, under the control of an actuator available to the user, is intended to come alternately to wear on the output contact 11B and away from it.

For simplicity, the actuator at the arrangement of the user has not been shown in the figures.

It has however been shown in broken lines 15, or 15 ', in Figure 1.

In practice, this is a rocker mounted key around an axis A ₁ , or A ′ ₁ , along one or the other of two orientations orthogonal to one another.

In the embodiment shown, the mechanism switch 10 according to the invention comprises, remotely one on the other, two output contacts 11B, against which the conductive broom 13 carries alternately.

The switch mechanism 10 according to the invention therefore comprises, in this embodiment, three terminals connection, namely a 12A connection terminal and two connection terminals 12B.

These connection terminals 12A, 12B all have the same constitution.

In practice, these are screw connection terminals, that is to say connection terminals implementing, from a share, a block 16, which has a hole 17 for engagement of an electrical conductor, and, on the other hand, a screw 18, which is engaged by screwing in a threaded hole 19 orthogonal to drilling 17 above.

The assembly is housed in a housing 20, which, in the embodiment shown, is in the general form of cassette and comprises a body 21 and a cover 22.

For housing the connection terminals 12A, 12B, the body 21 has cells 24A, 24B, which communicate each with the outside by a recess 25A, 25B at the level of the drilling 17 of block 16 of connection terminal 12A, 12B corresponding.

For access to screw 18 of these connection terminals 12A, 12B, the cover 22 has, itself, in line with the cells 24A, 24B of the body 21, of the wells 26A, 26B.

The attachment of the cover 22 to the body 21 takes place for example using screws, not shown.

To do this, the cover 22 has, at a distance one from the other, in the embodiment shown, two holes 27, each arranged respectively in line with two well 28 provided in correspondence in the body 21, projecting on the bottom 29 thereof.

In the embodiment shown, the body 21 of the housing 20 has, in addition, externally, projecting, two tongues 30, which extend generally back to back, in alignment with each other, to facilitate, for example, its maintenance and wedging in any housing.

In a manner known per se, the conductive brush 13 comprises, a middle branch 32, by which it is integral of the input contact 11A, and two lateral branches 33, which generally extend towards each other, and which, in positions diametrically opposed to each other, are in pivoted socket, according to arrangements described more in detail later, with a central tilting nut 34, this central tilting nut 34 being itself pivotally mounted, in the housing 20, under the control of a control member 35, between two positions, namely, a position for which the conductive brush 13 bears on one output contacts 11B, as shown in the figure 5, and a position for which it is on the contrary excluded from this output contact 11B and relates to the other output contact 11B, as shown in FIG. 6.

In practice, in the embodiment shown, the input contact 11A is directly formed by the terminal of corresponding 12A connection, and more precisely by the block 16 thereof.

The conductive brush 13 is therefore directly integral of this block 16.

For example, and as shown, it is set on this block 16, thanks to a widening 36 of its branch median 32, Figure 3.

As a corollary, the output contacts 11B are formed by protruding bosses on block 16 of the terminals corresponding 12B connection.

In the embodiment shown, these contacts outlet 11B each have a contact grain 37 on the surface.

According to the invention, the lateral branches 33 of the conductive broom 13 are in continuity with its middle branch 32, each connecting to it by an elbow 38 largely rounded, the conductive broom 13 is suitable for carrying on either of the output contacts 11B through either of its lateral branches 33, and either of the two 11B output contacts are located near the nut tilting center 34, so that by each of these side branches 33, and as it will appear subsequently, the conductive brush 13 is locally the object a transverse self-cleaning movement when pressed on an output contact 11B.

By transverse movement is meant here a movement substantially perpendicular to the axis A ₂ of the output contact 11B concerned, this axis A ₂ being generally defined by the direction in which it projects from the block 16 of the corresponding connection terminal 12B .

In practice, the conductive brush 13 comes from a single holding a suitably cut metal strip and consistent.

In practice, too, it is elastically deformable.

Overall, the conductive brush 13 closes in loop on the central tilting nut 34.

By its middle branch 32, it is leaned against a wall 40 of the body 21 of the housing 20.

To allow the deflection of the central nut of tilting 34, this middle branch 32, which, moreover, is generally rectilinear, comprises, in its middle part, a curved portion 41, which generally extends along an arc in a circle, with its concavity oriented towards the side of the branches lateral 33, and by which it is engaged in a notch 42, complementary, of the wall 40 of the body 21 of the housing 20.

Therefore, the input contact 11A is in position eccentric with respect to the central tilting nut 34.

In other words, this input contact 11A is closer of one of the lateral branches 33 of the conductive brush 13 than of the other of these.

Preferably, and as shown, the elbow 38 by which each of the side branches 33 of the broom conductor 13 connects to its middle branch 32 extends at an angle to the center C, which, at rest, as shown in Figure 3, is greater than 180 °, one of the wings of this elbow 38 being in continuity with the middle branch 32 while that the other of these wings forms with the lateral branch 33 concerned a dihedral D, which is widely open, and whose concavity is turned on the opposite side to the middle branch 32.

In other words, each of the lateral branches 33 has a fold 43 at the connection with the elbow 38 to which it follows.

Together, the output contacts 11B, and therefore the blocks 16 of the connection terminals 12B which carry them, extend slightly obliquely to the branch center 32 of conductive brush 13, converging one towards the other towards this middle branch 32.

In other words, and as is better visible in FIGS. 5 and 6, their axes A ₂ converge towards one another in the direction of this middle branch 32.

Preferably, and as shown, each of the lateral branches 33 of the conductive brush 13 is engaged with the central tilting nut 34 by a bead 44 of rounded cross section, central tilting nut 34 having a complementary groove 45 of section rounded transverse.

In practice, in the embodiment shown, the bead 44 of the lateral branches 33 of the conductive brush 13 is formed by a fold over on itself of the end of these.

In practice, for their support on the contacts of outlet 11B, and, more precisely, on contact grain 37 carried by these, the lateral branches 33 of the broom conductor 13 are themselves each fitted, projecting, of a contact grain 47.

As shown diagrammatically by its trace in FIGS. 5 and 6, the axis A ₃ of the central tilting nut 34, which is, of course, parallel to the transverse direction of the strip constituting the conducting brush 13, is perpendicular to the bottom 29 of the body 21 of the housing 20.

In practice, in the embodiment shown, this pivot axis A ₃ is materialized, on the one hand, by a shaft end 48, which extends projecting, cantilevered, on the inner surface of the cover 22 of the housing 20, as can be seen in FIG. 2, and which is intended to be engaged in rotation in a blind bore 49 provided for this purpose in the central tilting nut 34, and, on the other hand, by a pin 50, which projects on the opposite face of this central tilting nut 34, in alignment with the previous blind bore 49, and which is intended to be engaged in rotation in a blind housing 51 provided for this purpose recessed on the bottom 29 of the body 21 of the housing 20, as is also visible in Figure 2.

Of course, the grooves 45 of the central tilting nut 34 extend parallel to its pivot axis A ₃ .

These grooves 45 extend generally back to back, in each affecting respectively the end of two parts relatively tapered from this central tilting nut 34.

In the embodiment shown, the control member 35 of the central tilting nut 34 is a lifting beam, which is pivotally mounted about an axis A ₄ parallel to the pivot axis A ₃ of this central tilting nut 34, at a distance from the latter, and which, through a recess 53, is engaged, with play, on a lug 54 carried for this purpose by the latter.

Overall, the control member 35 is in the general form of a plate, which is inserted, flat, between the body 21 of the housing 20 and the cover 22 thereof, in favor of a clearance 55 provided hollow for this purpose on the inner surface of this cover 22, and, for the intervention of the actuating member 15 or 15 'available to the user, it projects outside the together at its end opposite its pivot axis A ₄ .

In practice, the pivot axis A ₄ of this control member 35 is materialized by two pins 56, only one of which is visible in FIG. 2, and which, projecting back to back on the two opposite faces of this member 35, are each respectively in rotation with two holes 57 provided in correspondence one on the body 21 of the housing 20, between the cells 24B, the other on its cover 22, between the wells 26B.

By its recess 53, the control member 35 is also engaged on the shaft end 48, and, so that it does not interfere with it, this recess 53 forms, laterally, two lobes 58.

For its own control, the spreader forming the organ 35 control door, projecting, outside the housing 20, and parallel to each other, two pins 60 between which can intervene the actuator 15 or 15 'at the available to the user.

In practice, these lugs 60 extend parallel to the pivot axis A ₄ of the control member 35, and, likewise, the lug 54 of the central tilting nut 34 extends parallel to the axis pivoting A ₃ thereof.

At rest, the conductive brush 13 carries by one of its lateral branches 33 on one of the output contacts 11B, for example the one on the left, as shown in the figure 5, and therefore puts the input contact 11A in electrical connection with this output contact 11B.

For the corresponding overall configuration of the conductive broom 13, elbow 38 corresponding to the branch lateral 33 concerned of it is the subject of a slight elastic torsional stress.

As a corollary, the elbow 38 associated with the other of the lateral branches 33 of the conductive brush 13 is the subject of a significantly more elastic torsional stress, this which leads it to close in on itself at an angle to the center C 'clearly greater than the angle at center C at rest.

When, under the request of the actuating member 15 or 15 'available to the user, the control member 35 is forced to switch from one of its positions to the other, by rotation around its pivot axis A ₄ , as shown diagrammatically by the arrow F1 in FIG. 5, the central tilting nut 34 is itself forced to tilt, from one of its positions to the other, by rotation around its axis of pivoting A ₃ , as shown diagrammatically by arrow F2 in FIG. 5.

During the rotation of the central nut of tilting 34, that of the lateral branches 33 of the broom driver 13 who was pressing against one of the contacts of exit 11B is forced to move away from it, while the other, which had hitherto been separated from the other output contacts 11B, on the contrary is constrained by get closer to the latter, until it comes to support in turn against it, as shown in Figure 6.

But, in doing so, both of the branches lateral 33 of the conductive brush 13 are first of all the object of a accentuation of their bracing against the central nut of tilt 34, and this temporarily results in an unwinding relative elasticity of the elbows 38 to which they follow.

This is the case until a sudden crossing of a neutral setting corresponding to when they are substantially aligned with each other.

The lateral branch 33 initially separated by a output contact 11B then abruptly presses on the latter, as shown for the lateral branch 33 of right in Figure 6.

It is therefore with this output contact 11B that the input contact 11A is electrically connected by the brush conductor 13, while the other side branches 33 of this and the other output contact 11B are duly located separated from each other.

In such a case, the switch mechanism 10 according to the invention operates as an inverter, that is to say in back and forth.

But, as previously stated, it can also operate as a switch, if, for example, it is substituted, at one of the output contacts 11B, a simple rest pad.

Anyway, in the final phase of his approximation with an output contact 11B, each of lateral branches 33 of the conductive brush 13 is the subject of a circular movement, which is deduced from that of the bead 44 by which it engages the central nut of tilt 34, and which has, with respect to this contact of output 11B, and, more precisely, with respect to the contact grain 37 carried by it, a transverse component of which it results in a self-cleaning of this contact grain 37 as well than its own contact grain 47.

It is the same when such a lateral branch 33 departs from output contact 11B against which it was until then in support.

Claims (10)

1. A switch mechanism of the kind comprising on the one hand at least two fixed contacts, namely for example an input contact (11A) and at least one output contact (11B) which are each respectively electrically connected to two connecting terminals (12A, 12B) and on the other hand a conductor blade (13) which comprises a central limb (32) by way of which it is fixed with respect to the input contact (11A) and two lateral limbs (33) which in mutually diametrally opposite positions are pivotably engaged with a central rocking tumbler (34), said central rocking tumbler (34) itself being mounted pivotably under the control of an actuating member (35) between two positions, namely a position in which the conductor blade (13) bears against the output contact (11B) and a position in which in contrast it is moved away therefrom, characterised in that, the lateral limbs (33) of the conductor blade (13) being continuous with the central limb (32) thereof, each being connected to the central limb by a widely rounded bend portion (38), and said conductor blade (13) being capable of bearing against the output contact (11B) by way of one of its lateral limbs (33), said output contact (11B) is disposed in the proximity of the central rocking tumbler (34) in such a way that, by way of said lateral limb (33), the conductor blade (13) is locally the subject of a transverse self-cleaning movement when it bears against said output contact (11B).
2. A switch mechanism according to claim 1 characterised in that each of the lateral limbs (33) of the conductor blade (13) is in engagement with the central rocking tumbler (33) by an enlargement portion (44) of rounded cross-section, said central rocking tumbler (34) comprising in complementary manner a groove (45) of rounded cross-section.
3. A switch mechanism according to claim 2 characterised in that the enlargement portion (44) of the lateral limbs (33) of the conductor blade (13) is formed by the ends of the lateral limbs being folded back on to themselves.
4. A switch mechanism according to any one of claims 1 to 3 characterised in that the bend portion (38) by way of which each of the lateral limbs (33) of the conductor blade (13) is connected to the central limb (32) thereof extends at an angle at the centre (C) of greater than 180°, one of its legs being in a relationship of continuity with said central limb (32) while the other forms with the lateral limb (33) in question a dihedral angle (D) which is widely open and the concavity of which is directed on the side opposite to the central limb (32).
5. A switch mechanism according to any one of claims 1 to 4 characterised in that the input contact (11A) is in an eccentric position, said input contact (11A) being closer to one of the lateral limbs (33) of the conductor blade (13) than the other of said limbs.
6. A switch mechanism according to any one of claims 1 to 5 characterised in that the actuating member (35) for the central rocking tumbler (34) is a rocking lever which is mounted pivotably about an axis (A₄) parallel to the axis of pivotal movement (A₃) of said central rocking tumbler (34) and which is engaged with play by way of an opening (53) on a lug (54) carried in projecting relationship for that purpose by the central rocking tumbler.
7. A switch mechanism according to claim 6 characterised in that, for its own actuation, the rocking lever forming the actuating member (35) carries in projecting relationship in mutually parallel relationship two lugs (60) between which can be operatively disposed an operating member (15, 15') available for the user.
8. A switch mechanism according to any one of claims 1 to 7 characterised in that, for co-operating with the output contact (11B), the lateral limb (33) in question of the conductor blade (13) carries a contact point member (47) in projecting relationship.
9. A switch mechanism according to any one of claims 1 to 8 characterised in that the output contact (11B) extends inclinedly with respect to the central limb (32) of the conductor blade (13).
10. A switch mechanism according to any one of claims 1 to 9 characterised in that it comprises at a mutual spacing two output contacts (11B) against which the conductor blade (13) alternatively bears.

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