Electromagnetic switch mechanism with manual reset device

The present invention relates to a switch mechanism electromagnetic manual reset whose activation is controlled by a control voltage associated with a supplementary circuit which, lowering below a predetermined threshold, causes the automatic disarming and DC switch are restored until the voltage conditions initials and the mechanism to be manually reset.

The currently available on the market various switch mechanisms which close an electrical circuit when the user acts on a push button, this action being enabled only if there is a voltage in the control circuit Annex. This type of mechanism is very useful for monitoring circuits power on electrical safety mechanisms in which the user does not act directly on the power circuit, but on an auxiliary circuit control.

To avoid this problem, relays are used which open the contacts main circuit if the voltage drop that crosses below a certain threshold; it is very often a load located on the driver power that directly control the relay. These relays are activated manually by means of a pushbutton which is actuated through directly responsible for the control of the movement of the contacts causes self-latching said relay. This type of two assembly main disadvantages: firstly, when switching intensities high, it consumes a lot of energy since it has, through a coil provide the thrust needed for the proper functioning contacts and, secondly, it is bulky and not very compact.

well known in particular from document FR 2,547,454 a mechanism electromagnetic switch with manual reset:<ul><li>a base on which is mounted at least one fixed contact,</li><li>at least one movable contact associated with a movable element and mounted on the base to be movable between an open position and a position of closing,</li><li>an elastic return means of the moving contact in its open position, </li><li>arming means for placing and maintaining the moving contact in its closed position, the arming means comprising a rod weapons provided with a mobile crew hooking lip associated with movable contact, elastic return means of the cocking rod in an armed position in which, when the lip of the cocking rod is engaged with the movable element associated with the movable contact, the contact mobile is pressed against the fixed contact in its closed position against the elastic restoring force exerted by the return means that it is associated, and detent means ensuring the attachment of the lip of the cocking rod with the movable element associated with the movable contact when the cocking rod is thrust in a shift position to against the return force exerted by the elastic return means that it is associated,</li><li>Automatic disarming means for causing the dropout mobile associated with the mobile contact assembly vis-à-vis the catching lip of the cocking rod and hence the return of the movable contact in its position opening under the effect of elastic return means associated therewith, these disarming means comprising an electromagnetic actuator with fault current comprising a movable actuating element movable between disarmament a position in which he is remembered by an average of associated elastic return, when the voltage across the actuator electromagnetic falls below a predetermined threshold for cause dropping of the moving vis-à-vis contact lip hooking of the cocking rod, and an armed position in which it is placed under the influence of the cocking rod, when pressed in shift position via latching means, and in which it is held against elastic return means associated when the voltage of the electromagnetic actuator exceeds a voltage threshold, predetermined.</li></ul>

In this mechanism, the engaging means comprise a inclined ramp associated with the base and disposed on the trajectory of the rod weapons to mechanically print this rod bending when manually pushed in engagement position. By bending the rod Arming engages, through his lip with the mobile equipment associated with movable contact and pushes the movable member of the electromagnetic actuator in cocked position. When the cocking rod is released to return arming position, it is held bent by the movable member the electromagnetic actuator is turned on so as to remain in engagement with the mobile equipment associated with the moving contact and to press as the moving contact against the fixed contact. This configuration is maintained as long as the actuator Electromagnetic is on. But as soon as the voltage across this actuator drops below the predetermined threshold, the movable member this actuator is returned elastically toward its disarming position to cause the dropout mobile associated with the mobile contact assembly vis-a-vis of the hooking lip of the cocking rod. The mobile contact then moves away spontaneously under the effect of elastic return means that it are associated, the fixed contact.

This type of mechanism provides satisfaction in theory. It allows indeed solve two main drawbacks relating to the energy consumption and congestion listed above. However, from a practical point of view, the embodiment of the means engagement with flexible arms rod cooperating with a ramp inclined not completely satisfied as to its reliability. It occurs Indeed, in use, wear of the friction surfaces of the rod and of the ramp inclined that may cause malfunctions. In addition, it is necessary to provide means for adjusting the inclined ramp to adjust the position flexed engagement of the cocking rod, both during manufacture the mechanism that during a subsequent maintenance operation aimed to consider any drift due to wear. This results in particular increased complexity and hence extra cost in the manufacture of mechanism.

In this context, the object of the invention is to design a mechanism electromagnetic switch with manual reset, which means engagement present structural mechanical and functional reliable than that provided for in the existing mechanisms.

In order to achieve this purpose, the invention provides a electromagnetic switch mechanism with manual reset type supra, wherein the locking means comprise a rocker or trigger that is mounted on the movable element associated with the movable contact for pivotable between a cocking position and a disarm position and possesses :<ul><li>a shoulder adapted to cooperate with the end of the cocking rod in such so that the latter, when manually pushed into position interlocking, forces the rocker to pivot into its armed position,</li><li>a lip arranged to make engagement with the lip of the cocking rod when the lever is in the armed position,</li><li>a lever arm coupled to the movable element of the electromagnetic actuator such that the cocking position and a decocking the movable element and the rocker correspond.</li></ul>

On the other hand, the flexibility of the cocking rod is also a source difficulty: the stem should be flexible enough not to offer a too much resistance to the depression that threatened to prematurely wear the inclined ramp or its own contact surface with the ramp but must be mechanically strong enough not to break prematurely including through wear fatigue resulting from these repeated bending.

With this mechanical arrangement according to the invention, no parts (Other than the elastic return means) is subject to bending or even any deformation, so no risk of fatigue failure is to fear. In addition, the friction is limited to those acting between the rod arms and the shoulder of the rocker arm; these frictions are very limited in their scale and have no functional character since only account the arming mechanism of operation the proper pivot of the balance. Moreover, even in case of wear, contact surfaces of the shoulder of balance and cocking rod, the proper arming mechanism obtained by a depression more or less pronounced in the arming rod, in any case, stop up the pendulum in its set position. The possible wear of the rod and / or the shoulder of the rocker is thus automatically caught by the race of armaments rod that is not limited. In addition, the cocking rod is not caused to deform, it can be made of a sufficiently strong and rigid material to resist properly and sustainably to the stresses to which it is subject when the arming operation.

Moreover, the fact that, when switching the pendulum engages with the cocking rod by tilting enables a safer stall its lip with the corresponding lip of the cocking rod. Conversely, for symmetrical reasons, the automatic mechanism of disarmament tilting in opposite direction of the beam is obtained with high security of operation, insofar as in its disarming position, lip of the pendulum provides no outlet to that of the cocking rod.

Other features and advantages of the invention will become apparent to the reading the description which follows of an embodiment in particular the invention given by way of example.

Reference is made to the accompanying drawings, in which:<ul><li>Figure 1 is a perspective view of the mechanism according the invention;</li><li>Figure 2 is a longitudinal sectional view of the same mechanism;</li><li>Figure 3 is a plan view of the same mechanism.</li></ul>

Referring to the figures, an electromagnetic switch mechanism Manual reset of the invention comprises two pairs of contacts 4, 11 closing or opening an electric circuit on which the mechanism switch is mounted. In each of those contact pairs, there are a fixed contact 4 which is fixed to a base 2 associated with the frame of the entire switch mechanism, and a movable contact 11 carried by a support 20 in shaped bracket one wing of which is itself fixedly mounted on one of the ends of an elastic blade 3 made of sheet steel of which the other end is fixed based 2.

Each of the two movable contacts 11 is thus movable between a position closure in which it is in contact with the fixed contact 4 with which it is associated and an open position in which it is spaced from said fixed contact and to which it is returned elastically under the effect of the inherent elasticity of the arm 3 matching.

The other wing of the support bracket 20 is connected to the corresponding flange of the other support bracket 20 which is associated with the other movable contact 11, by a cross 15. The cross bar 15 which extends along the two corners of support for mobile contacts 11 form a pin materializing an axis pivot, as will be better explained later.

The unitary assembly formed by the two brackets 20 associated with the two mobile contacts 11 and the crossbar 15 that links the two brackets as well moving equipment 28 associated with the movable contacts 11.

arming means are provided for placing and maintaining movable contacts 11 in their closed position, against the force of elastic return exerted by the resiliently flexible arm 3.

These arming means comprise a cocking rod 8 which is slidably mounted on the base 2 along a substantially perpendicular to axis that defined by the cross member 15. The cocking rod 8 has one end upper region of the crossbar 15, which is provided with a hooking lip 17 able to hang the mobile equipment 20 associated with the moving contacts 11. A elastic return means 14 recalls the cocking rod 8 in a position cocking wherein when the lip 17 of the rod is engaged with the moving element 28 associated with the movable contacts 11, the movable contacts 11 are pressed against the fixed contacts 4 in their closed position to against the elastic return force exerted by the arm 3. More precisely, the elastic return means of the cocking rod 8 is in this case constituted by a helical spring 14 which surrounds the cocking rod 8 and is supported, on the one hand against the back of the base 2 opposite to the fixed contacts 4, and other hand against a manual push 5 attached to the lower end of the rod arms 8. The back of the base 2 is further provided with a sleeve 29 which mask spring 14 and in which the manual pushbutton 8 may sink without game, or with a reduced play.

Finally the arming means comprise latching means which ensure the attachment of the lip 17 of the cocking rod 8 with the crew 28 mobile associated with moving contacts 11 when the cocking rod is 8 thrust by means of the manual pusher 5 which is associated therewith, in a position interlocking against the return force exerted by the spring 14.

These latching means comprise a rocker or trigger 12 which is mounted on the journal formed by the crosspiece 15 of the mobile assembly 28 associated with the movable contacts 11 to pivot between a cocked and positron a disarmament position.

This balancer 12 includes a shoulder 22 which is adapted to cooperate with the end 23 of the cocking rod 8 such that the latter, when manually pressed in the on position, the strength pendulum 12 to pivot in its cocked position.

The rocker 12 also comprises a lip 16 which is arranged to make engagement with the lip 17 of the cocking rod 8 when the balance is cocked position. Thus, by its lip 16, the balance 12 involved in hooking the moving element 28 associated with the movable contacts 11 to the rod 8 weapons.

Finally, the rocker arm 12 is provided with two spaced parallel arms and forming a fork having a function of the lever arm, as will be better explained later.

The switch mechanism also comprises means Automatic disarmament capable of causing the dropout crew mobile 28 associated with the movable contacts 11 vis-a-vis of the gripping lip 17 of the cocking rod 8 and consequently the return of the movable contacts 11 in their open position by the elastic effect of the arm 3. These means disarmament comprise an electromagnetic actuator fault current 21. This actuator, known in itself, is not described in detail. Suffice it to state that the actuator includes a housing or receptacle 1 which includes a solenoid 35 of axis A comprising a winding 6 surrounded by a 7 ferromagnetic armature which is connected to a fixed ferromagnetic core 13 extending partially within the coil 6 along the axis A. A core ferromagnetic mobile 9 extends partly in the air gap 36 of the solenoid 35 along the axis A, in the extension of the fixed core 13, and can slide Within this solenoid according to the axis A between on the one hand a position disarmament in which it is returned in the opposite direction of the fixed core 13 by an associated elastic return means 10, when the voltage across the solenoid 35 falls below a predetermined threshold, and secondly a close cocked position of the fixed core 13, in which it is maintained against elastic return means 10 associated to it under the effect the magnetic field generated by the solenoid 35 when it is placed under a higher voltage said predetermined threshold.

In this case, the mobile ferromagnetic core 9 is in the form of a rod of which a portion is inserted in the gap 36 of the solenoid 35, and of which the remaining part protrudes from the housing 1 and has two shoulders 25, 26 defining therebetween a groove 27 in which the two are engaged pendulum arm 24 forming the lever arm 12. The elastic return means said actuating rod 9 is constituted by a helical spring 10 surrounding this bar and resting one hand against the housing 1 of the actuator electromagnetic 21 and the other against the corresponding shoulder 25 of bar 9.

In addition, the axis of the actuating rod 9 is substantially perpendicular to the cocking rod 8, as well as journal 15 embodying the axis Arm pivot 12. This arrangement allows to obtain a footprint as small as possible.

The fork 24 of the balance 12 is thus coupled to the movable bar 9 so that the positions of armament and disarmament of this bar Mobile 9 and 12 of the balance correspond.

Thus, arming, the arming rod 8 is pressed manually against the return force of the spring 14 which comes into contact, by its end 23 against the shoulder 22 of the balance 12, to force, prolonging its course to its engaged position, the rocker 12 to pivot toward its cocked position. Pivoting to its cocked position, the pendulum 12 Train, with its fork 24, the actuating bar 9 position weapons, against the elastic restoring force of the spring 10.

Meanwhile, the lip 16 of the rocker 12 engages the lip 17 of the cocking rod 8 in a tilting movement.

The cocking rod 8 can then be released. Two scenarios are then envisaged.

When the voltage across the solenoid 35 of the actuator electromagnetic 21 is above the predetermined voltage threshold, the arm actuating 9 is held in its cocked position by the field magnetic generated by the solenoid, against the elastic return force exerted by the spring 10. The rod 8 and held in engagement with the rocker 12 and hence the moving element 28 associated with the movable contacts 11, entails, under the effect of the elastic return force exerted by the spring 14 associated therewith, the moving element 28 and the movable contacts 11 in the closed position. We Note in this regard that, for this, the return force exerted by the spring 14 must be greater than that exerted by the resilient arms 3.

In contrast, in the event that the voltage across the solenoid 35 of the electromagnetic actuator 21 drops below the voltage threshold predetermined, releasing the cocking rod 8 is accompanied back actuating bar 9 in its disarming position under the effect of the elastic force of the spring biasing 10. In thus returning to its position of disarmament, the actuating rod 9 pushes the fork 24 of the balance 12 and forces it to return to its position in which disarmament hooking the lip 16 of the rocker arm 12 and the lip 17 of the rod armament 8 is broken. The arming rod 8 therefore can not lead the moving element 28 and the movable contacts 11 in the closed position and these latter remain therefore in the open position in which they are held by the elastic return force exerted by the arms 3.

A third scenario should be considered in the event that the switching mechanism, after being armed manually, is in army configuration, the movable contact 11 being in the closed position and lip 16 of the rocker 12 engages the lip 17 of the cocking rod 8, and where the voltage across the solenoid 35 of the electromagnetic actuator 21 falls below the predetermined threshold. In this case, the bar actuating 9 is returned by the spring 10 in its disarming position and results in the corresponding position the rocker 12. In this position disarmament, the lip 16 of the balance 12 is released from engagement with the lip 17 of the cocking rod 8 and releases thereby the moving equipment 28 and movable contacts 11 which returning spontaneously under the effect of the force of elastic return force exerted by the arms 3, in their open position.