EP0246131B1 - Electrical bistable commutating device - Google Patents

Abstract

The bistable mechanism comprises a sliding part (32) guided by a posterior pin (33) so as to be able to slide and rotate about the said pin (33). The part carries an anterior pin (43) which can be laterally offset when it contacts the end of the arm (17) of the moving contact (16) in order to cause rotation, and an intermediate pin (38) which cooperates with pads (45, 46) which bring the part into reverse rotation when it continues to advance in order to cause the triggering of the arm (17) of the moving contact. <IMAGE>

Description

The present invention relates to a bistable electrical switching device.

Electrical devices having a bistable switching mechanism have well-known advantages. These devices generally have two fixed contacts and a movable contact capable of being applied alternately against the fixed contacts by means of a bistable actuation mechanism driven by an electromagnetic motor member generally comprising a coil and a plunger core for actuating the mechanism. . The bistable nature of the mechanism allows the desired contact position to be maintained by the action of the elastic means of the bistable mechanism, even in the absence of electrical excitation of the coil, this excitation being only necessary to ensure the passage from one of the two contact positions to the other.

The disadvantage of known bistable mechanisms is that they are relatively complicated and expensive, in because of the high degree of reliability sought for a very large number of operations. This also results in a large footprint which opposes the current trend of miniaturization, while in addition we are increasingly seeking to insert electronic components or circuits inside the housings of this kind of device.

Another drawback of the known mechanisms comes from the significant efforts which are required of the drive means to ensure the passage from one position to the other in order to overcome the elastic means which ensure the high contact pressure required. It is therefore necessary to give the electromagnetic coil large dimensions in order to apply the necessary force.

Already known from US-A-4 386 338, a bistable electrical switching device comprising, in an appropriate housing, at least a first fixed contact and at least a second fixed contact, movable contact means intended to be applied alternately against one or other of the fixed contacts, an elastic means for maintaining a mobile contact applied against the fixed contact to which it has been directed, a mechanism for bringing the mobile contact means from a contact position to the other and comprising a movable contact actuating part returned by an elastic return means, which part is driven by a driving means actuating the mechanism, said actuating part being capable of assuming both a movement of translation and rotation but having a tendency, in the absence of a lateral stress with respect to this translation movement, to move only in translation, appears it in which the movable contact actuation means are pivotally mounted about an axis and have an arm inclined in one direction or the other relative to the path of displacement in translation of said actuation part, while said actuating part is provided with a relief which, when it comes into contact with said arm of the moving contact actuating means, deflects said actuating part under the ramp effect caused by the presence of said arm initially remaining in its tilted position. This device is intended to open or close two contacts simultaneously and comprises, for this purpose, a tilting means pushing, in one position, the movable contacts away from the fixed contacts and allowing, in another position, the movable contacts to reapply against the fixed contacts. Such a device requires an intermediate pivoting part carrying two cams to rotate the part. It requires the presence of a friction means to approximately maintain the contact opening position and cannot guarantee a stable position in the event of wear of the friction means. It therefore requires significant efforts to open or close the contacts. In addition, it does not make it possible to cause extremely sudden movements of the mobile contacts.

The present invention proposes to remedy these drawbacks and to provide a bistable electrical switching device in which the bistable mechanism comprises a very small number of parts and ensures a high contact pressure while requiring little effort during the passage from one contact position to the other, which makes it possible to undersize the electromagnetic motor means.

Another objective of the invention is to produce such a device which has high operating reliability.

Yet another objective of the invention is to produce such a device in which the relative movements of the contacts are carried out with great precision.

The invention relates to a bistable electrical switching device comprising, in a suitable housing, at least a first fixed contact and at least a second fixed contact, mobile contact means intended to be applied alternately against one or the other of the fixed contacts, an elastic means for maintaining a movable contact applied against the fixed contact to which it has been directed, a mechanism for bringing the movable contact means from one contact position to the other and comprising a piece of movable contact actuation recalled by an elastic return means, which part is driven by a drive means actuating the mechanism, said actuating part being capable of assuming both a translational and rotational movement but having a tendency , in the absence of a lateral stress with respect to this translational movement, to be moved only in translation, said mobil contact means es being pivotally mounted about an axis and having an arm inclined in one direction or the other relative to the path of movement in translation of said actuating part, while said actuating part is provided with '' a relief which, when it comes into contact with said arm of the movable contact means, deflects said actuation part under the ramp effect caused by the presence of said arm initially remaining in its inclined position, and comprising first fixed ramps relative to the housing and symmetrical on either side of the translation path of said actuating part, to cooperate with a relief of the latter characterized in that said arm carries the movable contacts and is inclined along that of the fixed contacts against which the movable contact means are applied and in that the first ramps cooperate with the relief so as to cause, during the advance of said part actuation its rotation in opposite direction to that caused by said arm of the movable contact means and finally, cause the tilting of said arm when the relief of the actuating part associated with said arm has exceeded the pivot axis of said arm.

If necessary, the elastic return means of the actuating part may be the same as the elastic means keeping the contact arm in its inclined position to apply the movable contact against the fixed contact, but it is preferably possible in order to '' avoid adjustment very delicate such a unique elastic means, use separate elastic means, one for the movable contact, the other to cause the return to the initial position of the elongated piece for actuating the movable contact.

Said actuating part of the movable contact can advantageously be guided in its movement by means of an elongated slide cooperating with a guide pin, the elastic return means of the actuating part being axially aligned with said slide and the force of the means drive such as, for example, an electromagnetic motor member also exerted in alignment so as to cause a displacement in translation of the actuating part as long as the latter is not deflected in rotation by the presence of the arm of mobile contact. The stud can be carried by the actuating part and, in this case, the slide is provided either in a metal piece attached to the housing, or directly in a wall of the housing.

Similarly, the two fixed ramps inclined on either side of the translation path of the actuating part could be made directly in the housing. However, it is preferable to make them in an added part, for example in the form of a window with converging inclined edges made in said part, the latter then being able simultaneously to serve as a pivoting range for the mobile contact and also, if desired, to anchoring point of the elastic means of the actuating part and of the movable contact, this fixed part being able, in addition, to be connected to the movable contact terminal to ensure the electrical connection between the movable contact and said terminal.

It is thus possible to produce a bistable device which, at the level of the mechanism, comprises only three parts, namely the actuating part, the above-mentioned fixed part, as well as the elastic member for returning the actuating part, the others moving parts, namely the movable contact with its spring and the drive means, for example the electromagnetic member, being necessary anyway.

The arm of the movable contact, intended to serve as a ramp for deflecting the corresponding relief of the actuating part, preferably extends beyond the pivot point of the movable contact to initiate the deflection movement in rotation of the actuating part. actuation before it reaches the pivot point of the movable contact.

The angle of inclination of the movable contact arm relative to the direction of movement in translation of the actuating part is preferably of the order of 10 ° to 30 ° or even 45 ° and, similarly, the angle of inclination in the opposite direction of the ramps bringing the actuating member towards its central position is of the order of 10 ° to 30 °, these values making it possible to obtain both the precision and the components of effort required .

Advantageously, the above-mentioned ramps can continue, in the direction of return to the position of the actuating part, by ramps in opposite directions forcing the actuating member to return to its initial central position even in the case where, for some reason, it would tend to stay a bit rotated in the rest position.

• la figure 1 représente une vue en coupe longitudinale d'un télérupteur selon l'invention,
• la figure 2 représente une vue de bout de ce télérupteur,
• les figures 3 à 6 représentent des vues de dessus, en coupe, du télérupteur au niveau du mécanisme et des contacts dans les différentes positions correspondant au fonctionnement.

Other advantages and characteristics of the invention will appear on reading the following description, given by way of nonlimiting example and referring to the appended drawing in which:

• FIG. 1 represents a view in longitudinal section of a remote control switch according to the invention,
• FIG. 2 represents an end view of this remote control switch,
• FIGS. 3 to 6 represent top views, in section, of the remote control switch at the level of the mechanism and of the contacts in the different positions corresponding to the operation.

Referring firstly to Figures 1 and 2, there is shown a remote control switch comprising an insulating plastic housing 1 provided, at its lower part, with the usual quick fastening means 2 on a rail and having two fixed contact terminals 3 , 4 and, opposite, a terminal 5 for movable contact. We also see, at an intermediate level, terminals 6, 7 for the control circuit. In the upper part of the housing is housed an electronic circuit 8 allowing electronic management of the switching, for example of the type limiting the duration of excitation of the electromagnetic coil and allowing the undersizing of this coil.

This electromagnetic coil 9, of usual construction but undersized compared to the dimensions which it should have if it were constantly traversed by the excitation current, is mounted on a usual coil support 10 and isolated from the lower part. of the housing by a usual insulating cover 11. The coil 9, whose axis extends parallel to the bottom of the housing 1, is capable of attracting, to the left in the direction of the arrow, a plunger core 12 ending in a drive end 13.

The two fixed contacts 14, 15, electrically integral with their respective terminals 3, 4, are arranged on either side of the median plane of symmetry of the device, as can be seen in FIG. 3, being inclined with respect to this plan. The movable contact 16, which has two opposite faces intended to cooperate, one with the fixed contact 14, the other with the fixed contact 15, is carried by an arm 17 in the form of a stirrup, as seen on the Figure 1, this arm 17 being pivotally mounted about a vertical axis, that is to say perpendicular to the lower bottom of the housing 1, to allow the movement of the movable contact 16 between its two extreme positions of contact with the fixed contacts 14 and 15 respectively.

The mechanism comprises a fixed metal piece 18, elongated and extending parallel to the bottom. This part 18 extends, at the rear, to form an extension 19, penetrating into terminal 5 to ensure the electrical connection with it after tightening. This part 18 has a tab 20 folded down and provided with a notch 21. It has, towards its front part oriented towards the terminals 3, 4, a tab 22 folded upwards, also provided with a notch 23 arranged in the median plane of the housing and at the same level as a hole 24 made in the arm 17 of the movable contact. Finally the front end 25 of the piece 18 is folded at a right angle upwards, forming a front plate provided with a central notch 26 aligned with the notch 23 and the hole 24, the central part of the upper edge 25 of the notch 26 being bent backwards at 27, as seen in FIG. 3, to form a step in which a bevelled end part 28 of the upper branch of the stirrup 17 is applied. At the lower part , the end 25 has a similar shape cooperating with a corresponding end 29 of the lower branch of the stirrup 17, the latter being thus permanently mounted so as to pivot around the vertical axis disposed in the median plane of the housing and s extending between the beveled ends 29 and 28.

It is therefore understandable that the movable contact 16 carried by the bracket 17 can pivot between the two contact positions with the fixed contacts 14, 15 around the vertical axis thus materialized. A retaining spring 30, fixed on the one hand in the notch 23 and on the other hand in the hole 24, tends to maintain the movable contact 16 in its position applied against one of the fixed contacts with the force component resulting from the tensile force of the spring and the angle between the axis of the spring and the direction of the arm 17. It can also be seen that the arm 17 has, on its lower branch, a beveled extension 31 which is therefore arranged backwards beyond the vertical axis pivoting arm or stirrup 17.

A metal or plastic actuator part 32 is slidably mounted under the fixed metal part 18. This part has, at its rear end, a guide and pivot pin 33 and an upper tab 34 provided with a transverse notch through which the rod of the end 13 of the moving element or core 12 passes, the rod having a diameter less than the width of the notch to allow a certain clearance, and the edge of the end 13 oriented towards the lug 34 having a rounded shape of a ball joint, the connection between the crew or core 12 and the lug 34 therefore allowing a certain play both in the direction of horizontal translation in the median plane of the housing and in pivoting in a horizontal plane in particular.

The stud 33, of circular cylindrical shape, can move in a slide formed by an oblong hole 35 formed in the bottom of the housing 1 which thus ensures the guidance of the stud 33, and therefore of the actuating part 32, in translation in the median plane of the housing but allows rotation in the horizontal plane around the vertical axis formed by the stud 33.

The part 32 also has a rectangular window 36 to allow passage of the tab 20 without this tab 20 being able to hinder the translational and rotational movements of the part 32.

Further forward, the part 32 has, before a window 37, a central cylindrical stud 38, this time oriented upwards.

At the front end of the window 37 and under it the part 32 has an eyelet 39 serving as an anchor point for the return spring 40 of said actuating part, the other end of which is fixed in the notch 21 of the lug 20 carried by the fixed metal part 18.

The front end 41 of the actuating part 32 is bevelled towards the front with a point rounded sliding on a relief 42 of the bottom of the housing. This end 41 also has a stud 43, of cylindrical shape, which is oriented upwards and it can be seen that the three studs 33, 38 and 43 are aligned in the median plane of the housing which contains the horizontal direction of sliding of the actuator 32.

In order to cooperate with the actuating part 32, the fixed conductive part 18, which carries the movable contact, has a first central opening 44 above the window 37, this opening, the dimension of which is greater than that of the window. 37, having two elongated lateral edges 45 and 46 converging towards the front and forming ramps inclined at 15 ° relative to the median plane, these ramps 45 and 46 continuing rearward by two more inclined ramps 47, 48 converging this backwards.

Furthermore, the front end of the part 18 also has a central window 49 allowing the passage of the stud 43.

The operation is as follows:

In the initial rest position shown in FIGS. 1 and 3, the core 12 is in the emerged position outside the coil and the actuating part 32 is in the rear centered position parallel to the median plane, in which it is held by the return spring 40, on the one hand, because the stud 33 prevents any lateral displacement of the posterior end and, on the other hand, because the intermediate stud 38 has come to center at the bottom of the opening 44 between the two ramps 47, 48. In this position, the front stud 43 of the actuating part is spaced from the projecting beveled end 31 of the lower branch of the stirrup 17 carrying the movable contact 16 which is applied against the fixed contact 14, the arm or stirrup 17 therefore being inclined relative to the median plane of the housing, as seen in FIG. 3.

If the coil 9 is now excited, the plunger core 12 rapidly penetrates the coil in the direction of the arrow and, by doing so, its end 13 drives, by means of the tab 34, the part 32 for actuation towards the front. The movement of the actuating part remains essentially a translational movement due to the posterior guide of the stud 33 in the oblong slide 35 and the action of the spring 40 which tends to keep the part 32 in the centered position.

The actuating part 32 therefore quickly arrives at the position shown in FIG. 4 in which the front stud 43 comes into contact with the beveled end 31, laterally pivoted, of the arm 17 of the movable contact 16 which remains firmly held in its position by the action of the spring 30. The arm 17, with its bevelled end 31, therefore forms an inclined ramp which, by cooperating with the front stud 43, rotates the actuating part 32 around the rear stud 33 clockwise , seen in Figure 4. The return component, exerted by the spring 40, has the sole effect of increasing the pressure of the movable contact on the fixed contact 14. However, this clockwise rotation movement soon brings the intermediate stud 38 in contact with the ramp 45 presented by the edge of the opening 44. This phase occurs when the anterior stud 43, continuing its course forward and to the right, has exceeded the level of the vertical axis l pivoting arm 17.

The continuation of the movement forward of the actuating part 32 is then accompanied, despite the resistance exerted by the spring 30 of the arm 17, by a counterclockwise rotation of the actuating part 32, this rotation being imposed by the ramp 45 which converges forward. When the part 32 reaches the position shown in FIG. 5, the arm 17 is therefore forced to tilt, against the 4 resistance opposed by its spring 30, the continuation of this tilting movement being imposed by the advance of the stud prior 43 which continues, under the influence of the ramp 45 cooperating with the stud 38, to approach the median plane in a counterclockwise movement of the actuating part 32 around its rear stud 33. Furthermore, very quickly, the spring 30, due to the change in position, will now exert its force in the direction tending to apply the movable contact 16 against the fixed contact 15.

When we reach the end of the anterior stroke of the core 12, and therefore of the actuating part 32, as shown in FIG. 6, the arm 17 has tilted and the new stable position of the movable contact has been obtained.

The electro-magnetic excitation is now removed, the relatively weak return spring 40 of the part 32 will pull it back towards its starting position, causing, due to the contact between the stud 43 and the arm 17 , a new rotation, this time clockwise, of the part 32. When the latter reaches, during its retraction, at the level of the projecting beveled end 31 of the arm 17, it is however incapable of causing a new tilting of the arm 17, the transverse component that the return spring 40 exerts on the stud 43 being much less than the transverse component of the contact spring 30 which firmly applies the movable contact 16 against the fixed contact 15.

Once the recoil movement has been sufficient for the stud 43 to exceed the beveled end 31, the return spring 40 tends, while continuing the recoil, to rotate the actuating part 32 counterclockwise to align it with the direction of translation parallel to the median plane of the housing, this arrangement being anyway obtained at the end of the recoil when the actuating part 32 returns to its initial position shown in FIG. 3 in which the central stud 38 is held at the bottom of the convergence zone of the posterior ramps 47, 48.

It is understood that an extremely simple mechanism has thus been made up consisting of two parts, one of which, namely the fixed movable contact carrier part 18, can be obtained by a conventional stamping-folding operation and the other of which , namely the actuating part 32, can easily be molded. Reliability is very important and tilting is achieved for sure with a minimum of effort.

Of course, the invention could be the subject of different variants.

Thus, the parts could be modified so that the same nipple plays the simultaneous role of the nipples 38 and 43. Similarly, the relative arrangement of the parts and their shapes can be modified according to environmental constraints.

Although the invention has been described with reference to a particular embodiment, it is understood that it is in no way limited thereto and that it can be made various modifications of shape and material.

The drive means of the device can also be different. Thus, for example, instead of driving the actuating part by an electromagnetic coil or other electric motor member, it could be driven manually, for example using a manual drive means, such as a pusher or lever.

The bistable function, in the case of a non-manual drive, can be, for example, controlled by an electronic circuit 8 suitable for operation as a timer, remote control switch, relay, time relay or the like.

Claims (12)

1. An electrical bistable commutating device comprising, in a suitable casing (1) at least one first fixed contact (14) and at least one second fixed contact (15), movable contact means (16) adapted to be applied alternately against one or the other of the fixed contacts, a resilient means (30) for maintaining a movable contact (16) applied against the fixed contact towards which it has been directed, a mechanism for bringing the movable contact means (16) from one contact position to the other and comprising an actuating member for the movable contact (32) which is returned by a flexible restoring means (40), the said member (32) being entrained by drive means (9) for actuating the mechanism, the said actuating means (32) being capable of assuming both a translatory movement and a rotatory movement but tending, in the absence of any lateral biasing in respect of this translatory movement, to move solely in a translatory sense, the said movable contact means being mounted to pivot about an axis (28-29) and having an arm (17) inclined in one direction or the other in relation to the path of translatory movement of the said actuating means (32), while the said actuating means (32) is provided with a relief member (43) which, when it comes in contact with the said arm (17) of the movable contact means (16) diverts the said actuating member (32) under the ramp effect caused by the presence of the said arm (17) which remains initially in its inclined position and comprising first ramps (45, 46) which are fixed in relation to the casing (1) and which are symmetrical in their disposition on either side of the translatory path of the said actuating means (32) in order to cooperate with a relief member on this latter (38), characterised in that the said arm (17) carries movable contacts (16) and is inclined towards that of the fixed contacts (14, 15) against which the movable contact means are applied and in that the first ramps (45, 46) cooperate with the relief member (38) in such a way that, during the forward movement of the said actuating means (32), they cause it to rotate in a direction opposite that caused by the said arm (17) of the movable contact means and so that they can finally produce a tilting of the said arm (17) when the relief member (43) on the actuating member associated with the said arm (17) has passed beyond the pivot axis (28, 29) of the said arm.

2. A device according to Claim 1, characterised in that it comprises a fixed member (18) having a window (44) of which two converging edges form ramps (45, 46).

3. A device according to Claim 2, characterised in that the said fixed member is conductive and carries the pivoting arm (17) of the movable contact (16).

4. A device according to any one of Claims 1 to 3, characterised in that the angle of inclination of the first ramps (45, 46) in relation to the direction of translatory movement of the actuating member (32) is of the order of 10° to 45°.

5. A device according to any one of Claims 1 to 4, characterised in that the arm (17) of the movable contact (16) has an extension (31) extending beyond its pivoting axis, the said extension producing the commencement of the rotary movement of the actuating member (32) when the relief member (43) on the said member comes in contact with said extension.

6. A device according to any one of Claims 1 to 5, characterised in that the angle of inclination of the arm (17) of the movable contact in relation to the direction of translatory movement of the actuating member (32) is of the order of 10° to 45°.

7. A device according to any one of Claims 2 to 6, characterised in that the arm (17) of the movable contact (16) is stirrup-shaped, having two arms which end in pivot bearings (28, 29), the said arm having a hole (24) for hooked engagement of the arm restoring spring (30), the other end of the said spring being fixed to a lug (22) provided on the said fixed member (18).

8. A device according to any one of Claims 1 to 7, characterised in that the actuating member (32) has at its end opposite that which carries the relief member (43) cooperating with the arm (17) of the movable contact a rear nipple (33) which is adapted for displacement in a slide (35) fixed in relation to the casing and serving for the translatory and rotatingly pivoting guidance of the actuating member (32).

9. A device according to any one of Claims 1 to 8, characterised in that the actuating member is entrained by an immersion core (12) provided with an end (13) cooperating with a lug (34) on the actuating member (32) with a translatory and rotary clearance.

10. A device according to Claims 2 and 8, characterised in that the actuating member (32) comprises on one of its faces the rear nipple (33) for guidance in a slide and on the other face an intermediate nipple (38) penetrating the window (44) in the fixed member (18), the two edges of which form first ramps (45, 46) and a front nipple (43) forming the relief member cooperating with the arm (17) of the contact, the said member (32) having a passage (36) through which can pass a lug (20) on the fixed member (18) for hooking engagement of one end of a spring (40) for returning the actuating member (32), the other end of said spring being fixed in an eye (39) in the said member.

11. A device according to Claim 10, characterised in that the window (44) the edges of which provide the two first ramps (45, 46) likewise comprises two rear edges in the form of second ramps (47, 48) for recentring the intermediate nipple (38) of the actuating member upon its return to the starting position.

12. A device according to any one of Claims 1 to 11, characterised in that the entraining means (9) is an electromagnetic coil.

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