EP1288986A1 - Control device for electrical apparatus without yoke - Google Patents

Abstract

The control mechanism (100) has a fixed contact (113) contacting a conductor brush (134). The brush has two side sections (132,133) with an engaging arm (140) which moves from one contact (114) to the other (111). The two side sections are parallel to each other and fixed into separate parts of the arm, and are maintained parallel in movement.

Description

The present invention relates generally to devices for control of electrical equipment such as for example switches of the push or toggle type, switches and circuit breakers.

It relates more particularly to a control device comprising at least one fixed contact in electrical connection with a terminal outlet connection, and a conductive broom which has a middle branch by which it is in electrical connection with an input connection terminal and two lateral branches, at least one of which carries a movable contact and which are engaged with a trainer movable pivotally between two positions, namely a first position in which said lateral branch of the conductive brush applies said movable contact to the fixed contact and a second position in which said lateral branch of the conductive broom moves said movable contact away from said fixed contact.

Document FR 2 606 208 already discloses a control device comprising at least one fixed contact in electrical connection with a terminal outlet connection and a conductive brush which has a middle branch forming a movable yoke on which the end of a finger swivels coach, and two lateral branches, at least one of which carries a movable contact which closes in a loop on a fixed input contact forming a fixed yoke on which they are articulated in two opposite support points of it.

However, such an arrangement has certain drawbacks.

First of all, the joints, and in practice these are joints of knife type, by which the conductive broom is in contact with the contact input, must provide a double function of swivel mounting and transmission of electric current.

Thus, when the current flows through the input contact and the brush conductor, there is a heating at the support points of the conductive brush and input contact, this heating depends on the intensity current flowing being large and random from a control device to another.

Such heating causes some degradation of the electrical performance of the control device, causing wear and oxidation of the support points in contact with the input contact and the brush conductor which can cause pollution and degradation of the grains of electrical contacts which constitute the mobile and fixed contacts.

To avoid such a heating phenomenon, provision is made, at the level joints of the conductive broom, grease to facilitate the pivoting of the conductive broom on the input contact and to absorb micro-arcs electrical contacts formed on opening and / or closing of electrical contacts.

However, the heating produced at the contact support points input and the conductive brush, when the current flows, causes a some liquefaction, even vaporization and degradation of this fat which then disperses in the housing of the control device and can no longer play its role of facilitating the pivoting of the conductive broom on the input contact and absorber of electric micro-arcs.

In addition, in such a control device, the number of elements distinct metal to be used for its constitution is relatively important.

In order to overcome the aforementioned drawbacks, it has been proposed in the document FR 2 735 609 a control device in which the mounting to swiveling of the conductive brush on the input contact has been removed and replaced by the fact that the two lateral branches of the conductive broom, in diametrically opposite positions with respect to each other, are engaged with a central tilting nut pivotally mounted under the control of an organ between two positions, namely a position for which the brush conductor relates to the output contact and a position for which it is at otherwise dismissed from it.

The main disadvantage of such a control device is that it puts always work a relatively large number of pieces for moving lateral branches of the conductive broom.

In order to resolve all of the aforementioned drawbacks, the present invention provides a new device control device electric as defined in the introduction, characterized in that said branches lateral are parallel to each other in each of the two positions of the coach and are moved simultaneously by the latter between these two positions while being kept parallel.

• chaque branche latérale est raccordée à la branche médiane par une articulation du type genouillère ;
• chaque branche latérale est raccordée à la branche médiane par un coude qui s'étend suivant un angle au centre C, qui, au repos, est supérieur à 180°, l'une des ailes de chaque coude étant en continuité avec ladite branche médiane tandis que l'autre forme, avec ladite branche latérale concernée, un pli dont la concavité est tournée à l'opposé de celle dudit coude ;
• chaque coude et chaque pli associés forment, à la jonction de chaque branche latérale avec la branche médiane, un ressort globalement en forme de S ;
• chaque branche latérale comporte, à proximité de son extrémité libre, un épaulement engagé dans une encoche de l'entraíneur, chaque contact mobile constitué par un grain de contact étant porté par ladite extrémité libre de chaque branche latérale concernée de sorte que ledit entraíneur agit sur chaque branche latérale au plus près du grain de contact qu'elle porte ;
• chaque branche latérale porte un contact mobile ;
• chaque contact fixe s'étend en oblique par rapport à la branche médiane du balai conducteur ;
• le dispositif de commande comporte, à distance l'un de l'autre, deux contacts fixes en liaison électrique avec deux bornes de connexion de sortie, contre lesquels les branches latérales du balai conducteur appliquent alternativement un contact mobile, lesdits contacts fixes et l'axe X de pivotement de l'entraíneur étant situés aux trois sommets d'un triangle isocèle ;
• le balai conducteur est un feuillard d'une seule pièce en bronze ressort précontraint ; et
• l'entraíneur comporte d'une seule pièce des moyens de commande à la disposition de l'usager, tels qu'une touche-poussoir ou une touche à bascule.

Other non-limiting and advantageous characteristics of the control device according to the invention are the following:

• each lateral branch is connected to the middle branch by a knee-type joint;
• each lateral branch is connected to the middle branch by an elbow which extends at an angle to the center C, which, at rest, is greater than 180 °, one of the wings of each elbow being in continuity with said middle branch while that the other forms, with said lateral branch concerned, a fold whose concavity is turned opposite to that of said elbow;
• each bend and each associated fold form, at the junction of each lateral branch with the middle branch, a generally S-shaped spring;
• each lateral branch comprises, near its free end, a shoulder engaged in a notch of the coach, each movable contact constituted by a contact grain being carried by said free end of each lateral branch concerned so that said coach acts on each lateral branch closest to the contact grain it carries;
• each lateral branch carries a movable contact;
• each fixed contact extends obliquely to the middle branch of the conductive brush;
• the control device comprises, at a distance from each other, two fixed contacts in electrical connection with two output connection terminals, against which the lateral branches of the conductive brush alternately apply a movable contact, said fixed contacts and the axis X of pivoting of the trainer being located at the three vertices of an isosceles triangle;
• the conductive broom is a single-piece strip of pre-stressed spring bronze; and
• the coach comprises in one piece control means available to the user, such as a push button or a rocker button.

The description which follows with reference to the appended drawings, given at title of nonlimiting examples, will make it clear what the invention consists of and how it can be achieved.

• la figure 1 est une vue schématique en perspective éclatée d'un mode de réalisation simplifié du dispositif de commande selon l'invention ;
• la figure 2 est une vue de face du dispositif de commande de la figure 1 à l'état assemblé ; et
• la figure 3 est une vue schématique de face de l'intérieur du boítier d'une variante de réalisation simplifiée du dispositif de commande selon l'invention.

In the accompanying drawings:

• Figure 1 is a schematic exploded perspective view of a simplified embodiment of the control device according to the invention;
• Figure 2 is a front view of the control device of Figure 1 in the assembled state; and
• Figure 3 is a schematic front view of the interior of the housing of a simplified alternative embodiment of the control device according to the invention.

In Figures 1 to 3, there is shown a control device 100 electrical equipment, here a back-and-forth, which includes an insulating box, formed by the assembly of two shells 101A, 101B, inside which is housed a control mechanism.

The shells 101A, 101B are here joined to each other using screws not shown, but we can also plan to join these two hulls by snap-fastening or welding or any other means.

To this end, the shell 101A carries, on its inner face facing the shell 101B, chimneys 102, 103 each provided with a thread 102A, 103A and the other shell 101B includes, in its front wall, openings 102B, 103B which are positioned in correspondence with the threads 102A, 103A when this is placed on the first shell 101A (see figure 2).

Thus, through openings 102B, 103B, one can introduce screws so as to screw them into the threads 102A, 103A.

The control mechanism comprises, at a distance from each other, two fixed contacts 111, 113 consisting of contact grains in electrical connection by means of rigid conductive strips 112, 114 with two terminals output connection not shown, for example connection terminals with screw of known type, for the electrical connection of electrical conductors from the power supply network.

In addition, it comprises a conductive brush 130 which comprises a branch middle 134 which is in electrical connection by means of a tongue rigid metal 134A which extends generally transversely to the said middle leg 134, with an input connection terminal not shown.

As shown in Figures 1 and 3, the conductive brush 130 has overall a U shape with two lateral branches 132, 133 which are connect to the middle branch 134 forming the bottom of the U.

The conductive brush 130 is secured to the shell 101A of the insulating housing of the control device 100, via its central branch 134 which is inserted between a platform 105 carried in console by the hull 101A and two feet 107 secured to two pillars also carried as a console by the shell 101A and positioned opposite said platform 105.

At rest, i.e. before assembling the different parts constituting the control device, as shown in Figure 1, the lateral branches 132, 133 of the conductive brush 130 extend according to Divergent straight directions.

After the assembly of the various component parts of the control 100, these lateral branches 132, 133 of the control device are engaged with a coach 140 which keeps them permanently in parallel to each other.

According to the embodiments shown in the figures, each lateral branch 132, 133 carries, at its free end, a movable contact 131 consisting of a contact grain projecting from the face of each branch lateral 132, 133 which is opposite the other lateral branch.

Of course, according to an alternative embodiment not shown, according to which the control device is a simple switch, we could provide that it has a single fixed output contact, a simple insulating pad then substituting for the other fixed contact. In this case, only one side branch of the conductive broom carrying a movable contact is used.

As shown more particularly in Figures 1 and 3, each lateral branch 132, 133 comprises, near its free end which carries the contact grain constituting the movable contact 131, a shoulder 132A, 133A engaged in a notch 145, 144 of the coach 140, so that said coach 140 acts on each lateral branch 132, 133 closest to the grain of contact she wears.

The coach 140 is advantageously pivotally displaceable at inside the insulating housing of the control device between two positions, at know a position for which a lateral branch 132 of the conductive brush 130 applies said movable contact 131 to said corresponding fixed contact 113 and a second position in which said lateral branch 132 of the brush conductor 130 discards said movable contact 131 from said fixed contact 113 corresponding.

Of course, depending on the embodiment of the control device shown, the second position of the coach 140 corresponds to setting support by the other lateral branch 133 of the conductive brush 130 of the other contact mobile on the other corresponding fixed contact 111.

The coach 140 comprises a cylindrical body 142 pierced with an orifice through 142A intended to engage on a pin carried by the inner face shell 101A, this pin consisting of a stud 104 bearing on its surface cylindrical outer of the radial fins 104A.

When the cylindrical body 142 of the coach 140 is positioned on the trunnion, the ends of the radial fins 104A bear on the surface internal cylindrical of said body 142. The pad 104 extends along the axis X around which pivots the coach 140.

In addition, the external surface of the cylindrical body 142 of the coach 140 advantageously carries control means available to the user constituted here by a rocker button 141 also called a joystick or crankpin rocker that emerges outside the housing of the control device at through an opening defined between the two shells 101A, 101B.

Opposite said rocker button 141, said outer surface of the body 142 of the coach 140 wears a skirt 143 which extends over a sector angular and the free edge of which includes said spaced slots 144, 145 one from the other and intended to cooperate with the shoulders 133A, 132A of the conductive broom 130.

Advantageously, the coach 140 is formed in one piece by example by molding a rigid plastic material.

When the coach 140 pivots around the X axis, its notches 144, 145 generally move in a circle C1 centered on the X axis and entrain, according to this circular movement, said lateral branches 132, 133 which are in taken with them, said lateral branches 132, 133 then being displaced simultaneously by the coach 140 while being kept parallel during their displacement.

Thus, advantageously, said lateral branches 132, 133 of the brush conductor 130 are parallel to each other in each of the two positions of the coach 140 corresponding to a support of one of the lateral branches on a fixed contact and are moved simultaneously by this last in a circular motion centered on the X axis between these two positions while being kept parallel.

Said lateral branches 132, 133 of the conductive brush 130 are therefore locally subject to a self-cleaning transverse movement during their separation at the opening of one of the fixed contacts 111, 113.

By transverse movement is meant here a movement substantially perpendicular to the axis A1 or A2 of the fixed contact 111 or 113 concerned, each axis A1, A2 being generally defined by the direction in which the contact fixed consisting of a contact grain protrudes from the rigid conductive strip 112, 114 who wears it.

In addition, to avoid possible sticking of each side branch 132, 133 on a fixed output contact, detachment is advantageously systematically assured that coach 140 acts as close as possible to each movable contact 131 carried by each of the lateral branches 132, 133.

To follow the pivoting movement of the coach 140 while remaining parallel to each other, each lateral branch 132, 133 is connected to the middle leg 134 which is fixedly held in the housing of the device control by a knee-joint type.

Preferably, and as shown in the figures, each branch lateral 132, 133 is connected to the middle branch 134 of the conductive brush 130 by a bend 135 which extends at an angle to the center C, which, at rest, as as shown in Figure 1, is greater than 180 °, one of the wings of each elbow 135 being in continuity with said middle branch 134 while the other form, with said lateral branch 132, 133 concerned, a fold 136 whose concavity is turned opposite to that of elbow 135.

As shown in Figure 1, the fold 136 formed between a wing of the bend 135 concerned and the corresponding lateral branch 132, 133 is a dihedral D which is widely open.

By cons, as shown in Figure 3, the fold 136 formed between a elbow wing 135 and the corresponding side arm 132, 133 is another elbow wide open.

Together, the fixed contacts 111, 113 and therefore at least part rigid conductive strips 112, 114 which carry them extend slightly oblique to the middle branch 134 of the conductive broom in converging towards each other in the opposite direction of this middle branch 134.

In other words, and as is better visible in Figure 3, their axes A1, A2 converge towards each other in a direction opposite to this branch median 134.

In addition, the pivot axis X of the coach 140 and the contacts fixed 111, 113 are arranged at the three vertices of an isosceles triangle.

As best shown in Figure 3, each elbow 135 and each fold 136 associated form, at the junction of each lateral branch 132, 133 with the middle leg 134, a spring 137 generally S-shaped.

The operation of the control device 100 described above is the next.

In one of the first and second positions of the coach 140, the lateral branches 132, 133 being parallel to each other, the brush conductor 130 carries, by one of these lateral branches 132, 133, on one of the fixed contacts 111, 113, for example the one on the right, as shown in the Figure 3, and so it puts the input connection terminal in electrical connection with the corresponding output connection terminal, via the contact between the contact fixed and the corresponding mobile contact.

In this position, the S-shaped spring 137 formed at the junction of the lateral branch 132 in contact with the fixed contact is slightly compressed, the elbow 135 corresponding at an angle to the center C "which is less than the angle at center C at rest.

As a corollary, the S-shaped spring 137 formed at the junction of the other lateral branch 133 whose movable contact is spaced from the fixed contact 111 is slightly stretched, the corresponding 135 elbow being closed in a angle at center C 'greater than angle at center C at rest.

The two lateral branches 132, 133 undergo in this state a elastic bending stress so that one of the springs 137 is compressed and the other is tense.

In this state, the compressed spring 137 accumulates energy which will released during the pivoting movement of the coach 140.

More particularly, when the user acts on the rocker key 141, the coach 140 pivots around the X axis and carries with it the branches lateral 132, 133 kept parallel to each other.

During the rotation of the coach 140, that of the lateral branches 132 of the conductive brush 130, which bears against one of the fixed contacts 113, is forced to move away from it, while the other, which was until then separated from the other of the fixed contacts 111, is on the contrary forced to move closer to the latter, until it comes in turn to press against it so as to apply the movable contact which it bears against the fixed contact 111.

During this movement, both of the lateral branches 132, 133 of the conductive brush 130 are first of all the object of an accentuation of their brace against coach 140 and this temporarily results in a accentuation of the winding of the elbows 135.

This is the case until suddenly a configuration of neutral point corresponding to the time when said lateral branches 132, 133 are halfway between the fixed contacts 111, 113 and rise overall transverse to the middle branch 134.

The lateral branch 133 initially separated from the fixed contact 111 comes then abruptly pressing on the latter after crossing the point death due to the release of energy from the initially compressed spring 137 which, after crossing neutral, tends to take the position taut equivalent to that which the other spring 137 had initially before the movement of the coach 140.

The spring 137 located at the junction of this lateral branch 132 and the middle branch 134 is compressed.

It is then with the fixed contact 111 that the input terminal, not shown, is in electrical connection by the conductive brush 130, while the other of the lateral branches 132 of the latter and the other fixed output contact 113 are duly separated from each other.

In such a case, the control device according to the invention operates in reverse, that is to say back and forth.

But, as previously stated, it can also work in simple switch, if, for example, it is substituted for any of the fixed output contacts an insulating rest pad.

Advantageously, in the final phase of its rapprochement with a fixed contact, each of the lateral branches 132, 133 of the conductive brush 130 is the object of a circular movement, which is deduced from that of the shoulder 132A, 133A by which it engages the coach 140, and which presents, vis-à-vis the fixed contact 111, 113, and more precisely vis-à-vis the grain of contact which constitutes it, a transverse component from which a self-cleaning of this contact grain as well as its own grain of contact.

It is the same when such a lateral branch 132, 133 deviates from the fixed contact 111, 113 on which it was previously supported.

Finally, advantageously, the conductive brush 130 is preferably a single piece of bronze strap comes out of prestressed spring and is positioned under stress in the housing engaged with the coach 140 so as to provide good support between the fixed contacts and the mobile contacts each time tilting movement of the coach 140.

Of course, as a variant, any other material can be used conductive spring effect for the conductive broom.

In other words, due to the manufacture under stress of the broom conductor 130 and the energy accumulated in each spring 137 at each bringing a lateral branch into contact with a fixed contact, the contact pressure between each fixed contact and each mobile contact is well ensured.

If the lateral branches of the conductive broom were released during operation, these would move beyond the position of the fixed contact corresponding, due to the release of the energy reserve accumulated in the spring 137 formed at the junction of each lateral branch 132, 133 and the middle branch 134 of the conductive brush 130.

The present invention is in no way limited to the embodiments described and represented, but the person skilled in the art will know how to make any variant conforms to his spirit.

Claims (10)

Control device (100) for electrical equipment comprising at least one fixed contact (113) in electrical connection with an output connection terminal, and a conductive brush (130) which comprises a central branch (134) by which it is in electrical connection with an input connection terminal and two lateral branches (132, 133) at least one of which carries a movable contact (131) and which are engaged with a driver (140) pivotally movable between two positions, namely a first position in which said lateral branch (132) of the conductive brush (130) applies said movable contact (131) to said fixed contact (113) and a second position in which said lateral branch (132) of the conductive brush (130) separates said movable contact (131) from said fixed contact (113), characterized in that said lateral branches (132, 133) are parallel to each other in each of the two positions of the driver ( 140) and are moved simultaneously by the latter between these two positions while being kept parallel. Control device (100) according to claim 1, characterized in that each lateral branch (132, 133) is connected to the middle branch (134) by a knee-joint type joint. Control device (100) according to claim 2, characterized in that each lateral branch (132, 133) is connected to the central branch (134) by an elbow (135) which extends at an angle to the center C, which , at rest, is greater than 180 °, one of the wings of each elbow (135) being in continuity with said middle branch (134) while the other forms, with said lateral branch (132, 133) concerned, a fold (136) whose concavity is turned opposite to that of said elbow (135). Control device according to claim 3, characterized in that each associated elbow (135) and each fold (136) form, at the junction of each lateral branch (132, 133) with the central branch (134), a spring (137 ) generally S-shaped. Control device according to one of the preceding claims, characterized in that each lateral branch (132, 133) comprises, near its free end, a shoulder (132A, 133A) engaged in a notch (145, 144) of the coach (140), each movable contact (131) constituted by a contact grain being carried by said free end of each side branch (132) concerned so that said coach (140) acts on each side branch (132, 133) as close as possible to the contact grain it carries. Control device according to one of the preceding claims, characterized in that each lateral branch (132, 133) carries a movable contact (131). Control device according to one of the preceding claims, characterized in that each fixed contact (111, 113) extends obliquely with respect to the middle branch (134) of the conductive brush (130). Control device according to one of the preceding claims, characterized in that it comprises, at a distance from each other, two fixed contacts (111, 113) in electrical connection with two output connection terminals, against which the lateral branches (132, 133) of the conductive brush (130) alternately apply a movable contact (131), said fixed contacts (111, 113) and the pivot axis X of the driver (140) being located at the three vertices of an isosceles triangle. Control device according to one of the preceding claims, characterized in that the conductive brush (130) is a strip of one piece made of prestressed spring bronze. Control device according to one of the preceding claims, characterized in that the coach (140) comprises in one piece control means available to the user, such as a push button or a button rocker (141).

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