High electrodynamic resistance and high breaking capacity switching device

The electrical contact switching device with a current loop configuration addresses the challenge of balancing electrodynamic short-circuit withstand and arc management by generating forces that maintain contact closure and facilitate arc dissipation, enhancing both performance aspects.

FR3163200A1Pending Publication Date: 2025-12-12SOCOMEC SPA
View PDF 10 Cites 0 Cited by

Patent Information

Application Number
FR2024005946
Authority / Receiving Office
FR · FR
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-06-06
Publication Date
2025-12-12

AI Technical Summary

Technical Problem

Existing pressure-activated electrical contact switching devices face challenges in achieving a balance between high electrodynamic short-circuit withstand and favorable arc management, as they either compromise on one or the other due to conflicting electromagnetic forces during load and overcurrent conditions.

Method used

A pressure-activated electrical contact switching device with a current loop configuration that generates compensating electrodynamic forces to maintain contacts in the closed position and facilitates opening under load or overcurrent conditions, while also directing electrical arcs towards external interruption chambers for efficient dissipation.

Benefits of technology

The device achieves strong electrodynamic short-circuit withstand and effective arc management by generating forces that facilitate contact opening and direct arcs away from the device, ensuring high cutting power and efficient arc interruption.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 00000000_0000_ABST
    Figure 00000000_0000_ABST
Patent Text Reader

Abstract

High Electrodynamic Resistance and High Breaking Capacity Switching Device: A switching device comprising two fixed contacts (2) separated from each other in a first direction (x) and a movable contact (3) in a second direction (z) perpendicular to the first (x) between a first position in contact with the two fixed contacts (2) and a second position out of contact with the two fixed contacts (2), at least one of the fixed contacts (2) has a return loop (22) attached to a base (20) at one end. The return loop (22) comprises at least one arm (221) disposed at a distance from the base (20) and from said at least one second electrical contact (3) in a third direction (y) orthogonal to the other two directions (x and z). Figure for the abbreviation: Fig. 1
Need to check novelty before this filing date? Find Prior Art

Description

Title of the invention: High electrodynamic strength and high breaking capacity switching device. Technical field

[0001] The invention relates generally to electrical pressure contact switching devices, and more particularly to an electrical pressure contact switching device comprising a current loop. Previous technique

[0002] It is well known to those skilled in the art that, for a pressure-contact electrical switching device, the principle of high electrodynamic short-circuit withstand and the principle of good arc management during switching are very often contradictory from a physics standpoint. Therefore, compromises must be made in the switching or short-circuit characteristics.

[0003] A pressure-activated electrical contact switching device with a current loop is known from document EP 3 979 279. This patent exploits the magnetostatic properties of the forces generated by the passage of a current in a conductor to generate compensating forces that maintain the moving contact in the closed position.

[0004] However, the object described in this document does not allow for a breaking device that provides an arc starting point favorable to the management of the electric arc. Furthermore, the designs proposed in this document do not allow for the generation of driving forces along the opening axis of the moving contacts when they open under overcurrent conditions.

[0005] A pressure-activated electrical contact interruption device with a current loop is also known from US patent 4,467,301. However, the arrangement of the current lines in the device described therein does not allow for the generation of driving forces along the opening axis of the moving contacts when they open under overcurrent conditions. On the contrary, the conductor located above the moving contacts tends to resist their opening. This design also does not provide an arc starting point conducive to arc control. Description of the invention

[0006] The invention aims to provide a pressure-activated electrical contact switching device comprising a current loop enabling a combination of strong electrodynamic short-circuit withstand and favorable arc management during load and overcurrent switching.

[0007] More explicitly, the proposed solution implements a pressure-activated electrical contact switching principle having a current loop that allows for the generation of significant electrodynamic forces to compensate for the repulsive forces present at the electrical contacts in the closed position, while also allowing for the generation of electrodynamic forces that tend to open the moving contact when opening under load or overcurrent.

[0008] Furthermore, the cutting device according to the invention aims to guarantee a cutting arc management physics which allows to address a high cutting power, in particular by electrodynamic forces at the level of the arc feet which tend to drive the arc from the electrical contacts in a favorable direction, in particular towards a cutting chamber.

[0009] In a first aspect of the invention, a switching device is proposed comprising two first fixed electrical contacts separated from each other in a first direction and at least one second movable electrical contact in at least a second direction perpendicular to the first direction between a first position in which it is in contact with the first two fixed electrical contacts and a second position in which it is out of contact with at least one of the first two fixed electrical contacts.At least one of the first fixed electrical contacts is a current-return contact comprising a base and a return loop, the return loop comprising a connection support and at least one arm electrically and mechanically connected between the base and the connection support, said at least one arm conducting the current along the first direction and in a direction opposite to the current flowing in the base and to the current flowing in said at least one second movable electrical contact when it is in the first position. And, said at least one second movable electrical contact extends parallel to the base in the first direction and above the base in the second direction, and is in direct electrical contact only with the connection support of the return loop when it is in the first position.

[0010] According to a general feature of the invention, said at least one arm of the return loop is disposed, along the third direction, at a distance from said at least one second movable electrical contact.

[0011] Said at least one second movable electrical contact is thus placed above the base of the first fixed electrical contact, the first fixed electrical contact being a current-return contact. This configuration allows for current lines in the base and in said at least one second movable electrical contact to be parallel and flowing in the same direction. Consequently, according to the rules of electromagnetism, said at least one second movable electrical contact is attracted to the base of each of the first contacts configured as a loop contact. back. The Laplace forces at work compensate for the repulsive forces generated on the contact surfaces during a short circuit.

[0012] At the same time, the arrangement of the two arms of the return loop on either side of said at least one second electrical contact, movable in the third direction, and at the same height as said at least one second electrical contact, movable, allows to have a negligible or even zero electromagnetic influence on the maintenance in position of said at least one second movable electrical contact when it is in the first position.

[0013] The current lines passing through said at least one arm are parallel to the current lines passing through said at least one second movable electrical contact, but in the opposite direction. This results in the generation of repulsive electromagnetic forces each time between an arm of the return loop and a second movable electrical contact.

[0014] But said at least one arm and the second electrical contact(s) being located in the same plane orthogonal to the second direction, these forces are oriented along the third direction, without any component along the second direction in which the forces of attraction between the base and said at least one second mobile electrical contact are exerted.

[0015] Conversely, when the breaking device is open and said at least one second movable electrical contact moves from the first (closed) position to the second (open) position, said at least one second movable electrical contact passes over, in the second direction, the line of said at least one arm of the return loop. The arms thus situated below the second movable electrical contacts then generate repulsive forces that are no longer solely in the third direction, but also include a component in the second direction that is in the same direction as the opening of said at least one second movable electrical contact. This force component does not impede the movement of said at least one second movable electrical contact, but, on the contrary, facilitates its opening.

[0016] Furthermore, the configuration of said at least one arm of the return loop with the configuration of the base and the configuration of said at least one second movable electrical contact ensures that electrical contact between a first fixed electrical contact of the return loop type and a second movable electrical contact occurs only at the return loop, and therefore, given the configuration of the current lines in the base, the arms, and said at least one second electrical contact, electrical contact is only made outwards from the first, fixed electrical contacts, in other words, only outwards from the breaking device. Consequently, any electrical arcs that might form when the device opens Interruption under load, that is, at the moment when at least one second moving electrical contact moves from the first position to the second position, will occur primarily on the outer portions of the interrupting device. This favorable arc initiation, due to the current loop effect, thus facilitates the dissipation and interruption of the electrical arc.

[0017] In a first embodiment of the cutting device according to the invention, in said first direction, the base can extend between a first end and a second end, and said at least one arm can extend between a third end connected to the second end of the base, and a fourth end connected to the connection support, said at least one arm being in electrical contact with the base only by its third end.

[0018] In a second embodiment of the switching device according to the invention, the connection support may include an axial protrusion extending in the first direction projecting outwards, opposite the base, and said at least one second movable electrical contact may extend in the first direction between a fifth end and a sixth end, the fifth end comprising a connection terminal in electrical contact with the axial protrusion of the connection support when said at least one second movable electrical contact is in the first position.

[0019] In a third embodiment of the breaking device according to the invention, the breaking device may further comprise, for each current return contact, a breaking chamber formed around the protrusion of the connection support and the connection terminal of said at least a second movable electrical contact cooperating with the connection support.

[0020] The arrangement of the current lines has been designed to achieve a favorable arc initiation when an arc occurs. In the electrical interruption device according to the invention, the interruption chambers are positioned in line with the contact surfaces. Due to the loop shape, when an arc occurs, it will be drawn by its own magnetic forces towards the end of the contact surface where the interruption chambers are arranged by magnetic blowing. The arc will thus tend to move towards the interruption chamber and not towards the internal area of ​​the product.

[0021] In a fourth embodiment of the switching device according to the invention, the switching device may include several second electrical contacts arranged in parallel with each other between the two arms of the return loop, each second movable electrical contact being spatially separated from the adjacent second electrical contact(s) along the third direction.

[0022] In a fifth embodiment of the cutting device according to the invention, the return loop may comprise two arms, the two arms being arranged, in the third direction, on either side of said at least one second movable electrical contact, and on either side of said base.

[0023] In a sixth embodiment of the cutting device according to the invention, said at least one arm of the return loop can be disposed, in the second direction, between the base and said at least one second contact when the latter is in the second position.

[0024] Preferably, said at least one arm of the return loop is disposed, along the second direction, at the same height as said at least one second contact when the latter is in the first position, or at the same height as the base.

[0025] In a seventh embodiment of the switching device according to the invention, the switching device may further comprise a carriage made of electrically insulating material, the carriage comprising at least one channel passing through the carriage in the first direction and through which is inserted a second, movable electrical contact, the carriage being movable in said second direction and driven by an actuator, and said at least one second electrical contact being driven in motion in said second direction by the carriage.

[0026] The channels of the electrically insulating carriage thus allow each of the second moving electrical contacts (or of the second contact when there is only one) to be guided along the second direction between the first position and the second position, that is to say between the closed position of the cutting device and the open position of the cutting device.

[0027] In an eighth embodiment of the cutting device according to the invention, the carriage may further include at least one pressure spring inside said at least one channel.

[0028] The spring makes it possible to increase the pressure of the second moving electrical contact against the first fixed electrical contact(s), and more particularly against the connection support(s).

[0029] In a ninth embodiment of the switching device according to the invention, the first two fixed electrical contacts can be placed, in the second direction, on either side of said at least one second movable electrical contact, and said at least one second electrical contact describes a rotational movement in a plane comprising said first direction and said second direction between the first position and the second position.

[0030] In a tenth embodiment of the switching device according to the invention, the first two fixed electrical contacts may be current-return contacts, and said at least one second movable electrical contact may comprise a terminal of connection in contact with one of the first two fixed electrical contacts, and a connection terminal in contact with the other first fixed electrical contact.

[0031] In this configuration, said at least one second, movable electrical contact pivots around an axis extending along the third direction to move from the first position to the second position.

[0032] In one variant, only one of the first fixed electrical contacts is a current return contact, the other first fixed electrical contact comprising an electrically conductive fixed support electrically and mechanically connected to said at least one second movable electrical contact, via a mechanically flexible link allowing said at least one second movable electrical contact to move from the first position to the second position. Brief description of the drawings

[0033] The invention will be better understood from the reading below, by way of example but not limitation, with reference to the attached drawings.

[0034] [Fig-1] [Fig.1] presents a schematic cross-sectional view of a switching device in closed position according to a first embodiment of the invention.

[0035] [Fig.2] Fig.2 presents a schematic perspective view of the switching device 1 of [Fig.1] in the closed position without the external housing and the switching chambers.

[0036] [Fig.3] The [Fig.3] presents a perspective view of the two fixed contacts of the switching device 1 of the [Fig.1].

[0037] [Fig.4] The [Fig.4] shows a side view of the two fixed contacts of the switching device 1 of the [Fig.1].

[0038] [Fig.5] The [Fig.5] presents a schematic perspective view of the switching device 1 in the open position without the external housing and the switching chambers.

[0039] [Fig.6] The [Fig.6] presents a schematic cross-sectional view of the switching device 1 of the [Fig.5].

[0040] [Fig.7] The [Fig.7] presents a schematic perspective view of the current flow in the first, fixed electrical contacts and the second, movable electrical contacts of the [Fig.1].

[0041] [Fig.8] Fig.8 presents a schematic cross-sectional view of the cutting device 1 of the first embodiment in the closed position.

[0042] [Fig.9] Fig.9 presents a schematic cross-sectional view of the cutting device 1 of the first embodiment in the open position.

[0043] [Fig. 10] The [Fig. 10] schematically represents a perspective view of a cutting device 10 in the closed position according to a second embodiment of the invention.

[0044] [Fig. 11] The [Fig. 11] schematically represents a perspective view of a cutting device 10 in open position according to a second embodiment of the invention.

[0045] [Fig. 12] The [Fig. 12] schematically represents a perspective view of a cutting device 100 in closed position according to a third embodiment of the invention.

[0046] [Fig. 13] The [Fig. 13] schematically represents a perspective view of a cutting device 100 in open position according to a third embodiment of the invention. Description of the implementation methods

[0047] The present invention will be described in relation to particular embodiments and with reference to certain drawings, but the invention is not limited thereto, but only by the claims. The drawings described are schematic only and are not limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. When the term "including" is used in this description and the claims, it does not exclude other elements or steps. When an indefinite or definite article is used to denote a singular noun, e.g., "a" or "an," "the," this may include a plural of that noun unless otherwise specified.

[0048] The term "comprising," used in the claims, should not be interpreted as being limited to the means listed below; it does not exclude other elements or steps. Thus, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting solely of components A and B. This means that, with respect to the present invention, the only relevant components of the device are A and B.

[0049] Furthermore, the terms first, second, third, and similar in the description and claims are used to distinguish similar elements and not necessarily to describe a sequential or chronological order. It should be understood that the terms thus used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operating in sequences other than those described or illustrated herein.

[0050] Figure 1 is schematically illustrated a cross-sectional view of a cutting device in the closed position according to a first embodiment of the invention, and Figure 2 is schematically illustrated a perspective view of the cutting device of Figure 1 without the external housing and the cutting chambers for greater readability.

[0051] As illustrated in Figures 1 and 2, the switching device 1 comprises two fixed first electrical contacts 2, three second electrical contacts 3, and a carriage 4 made of electrically insulating material. The first two electrical contacts 2 are fixed and separated from each other in a first direction x. The three second electrical contacts 3 are housed within the carriage 4, and the carriage and the three second electrical contacts 3 are movable together in a second direction z perpendicular to the inside of the carriage 4. The translational movement of the assembly formed by the carriage 4 and the three second electrical contacts 3 is initiated by acting directly on the carriage 4.

[0052] The three second electrical contacts 3 are movable between a first position in which they are in contact with the first two fixed electrical contacts 2 and a second position in which they are distant and out of contact with the first two fixed electrical contacts 2. When the movable second electrical contacts 3 are in the first position, the switching device 1 is in a closed position, and when the movable second electrical contacts 3 are in the second position, the switching device 1 is in an open position.

[0053] Figure 3 shows a perspective view of the first two contacts fixed electrical contacts 2 of the switching device 1 of the first embodiment. And in [Fig.4] is shown a side view of the first two electrical contacts 2 of [Fig.3].

[0054] As illustrated in Figures 1 to 4, the first two fixed electrical contacts 2 are so-called current-return contacts. Each first fixed electrical contact 2 comprises a base 20 and a return loop 22. The base 20 and the return loop 22 are electrically and mechanically connected together.

[0055] For each first fixed electrical contact 2, the base 20 has a length extending along the first direction x between a first end 202 and a second end 204, and a width extending in a third direction y orthogonal to the first direction x and the second direction z. The second end 204 of the base 20 is integral with the return loop 22 and the first end 202 of the base 20 is integral with a connecting foot 24.

[0056] The connecting foot 24 comprises a connecting portion 240 and a joining portion 242 integral with the connecting portion 240 on one side and with the base 20 on the other side. The connecting portion 240 extends in a plane parallel to that of the base 20, that is, a plane parallel to the first x direction and the third y direction, and at a height distinct from that of the base 20 along the second x direction. The joining portion 242 extends between the base 20 and the connecting portion 240 of the connecting foot 24, with at least a portion extending along the second z direction.

[0057] As illustrated in Figures 1 and 2, the second ends 204 of the bases 20 of the first two fixed electrical contacts 2 of the switching device 1 according to the first embodiment are opposite each other in the first direction x without being in contact.

[0058] For each first fixed electrical contact 2, the return loop 22 extends along the first direction x between a first end 222 and a second end 224. The return loop 22 further comprises two arms 221, each extending parallel to the first direction x between a first end 2212 coinciding with the first end 222 of the return loop 22 and a second end 2214 coinciding with the second end 224 of the return loop 22. The first end 2212 of each arm 221 is fixed to the second end 204 of the base 20. Each arm 221 is arranged, along the third direction y, on either side of the base 20.

[0059] The return loop 22 further includes a connection support 223 extending along the third direction y between the two arms 221 of the return loop 22 at the second end 224 of the return loop 22. The second end 2214 of each arm 221 is mechanically and electrically connected to the connection support 223. The connection support 223 includes an axial protrusion 225 projecting from the second end 224 of the return loop 22 along the first direction x, so that the contact area with the second movable electrical contacts 3 is outside the area covered by the arms 221 in the first direction x.

[0060] Each of the three second movable electrical contacts 3 extends along the first direction x between a first end 302 and a second end 304, forming a bar or rod of a length equal to the distance separating the connection support 223 from one of the first fixed electrical contacts 2 and the connection support 223 from the other first fixed electrical contact 2. Each of the two ends 302 and 304 has a downward-facing vertical projection 32, i.e., towards the axial protrusion 225 of the connection support 223 along the second direction z. Each projection 32 forms a connection terminal 32.

[0061] For each second movable electrical contact 3, having the connection terminals 32 extending outward from the bar in the second direction z allows the bar to be kept at a distance in the second direction z from the bases 20 of the first fixed electrical contacts 2, even when the second movable electrical contacts 3 are in the first position, i.e. when the breaking device 1 is in the closed position, with the connection terminals 32 in contact with the connection supports 223.

[0062] And as illustrated in Figures 1 and 2, the electrical connection between a connection terminal 32 and an axial protrusion 225 of the connection support 223 is outside, along the first direction x, of the area over which the arms 221 of the return loop 22 extend.

[0063] Figure 7 schematically shows a switching device 1 of Figure 1 in the closed position, but without the carriage 4 to simplify reading. As indicated by the dashed arrows, the configuration of the first fixed electrical contacts 2 with their base 20 and their return loop 22 and the second movable electrical contacts 3 allows, when the switching device 1 is in the closed position, a current flowing in the arms 221 of the return loops 22 to flow, along the first direction x, in a direction opposite to the direction of the current flowing in the base 20 and to the direction of the current flowing in each of the three second movable electrical contacts 3.

[0064] And since each electrical connection between a connection terminal 32 and a connection support 223 is outside, in the first direction x, the area over which the arms 221 of the return loop 22 extend, the currents flowing at the level of the arms 221 all flow purely in the first direction x.

[0065] The second mobile electrical contacts 3 are never in direct electrical contact with the base 20 of a first fixed electrical contact 2, regardless of the position in which the switching device 1 is located.

[0066] Figures 5 and 6 respectively illustrate a schematic perspective view and a schematic cross-sectional view of the cutting device 1 according to the first embodiment of the invention but in the open position. In other words, Figures 5 and 6 illustrate the same cutting device 1 as in Figures 1 and 2, but instead of being in its closed position, it is in the open position.

[0067] The difference between the closed position of the cutting device 1 illustrated in figures 1 and 2 and the open position of the cutting device 1 illustrated in figures 5 and 6 lies only in the position of the carriage 4 and the three second electrical contacts 3 movable along the second direction z.

[0068] In the closed position of the switching device 1 illustrated in Figures 1 and 2, each bar forming a second movable electrical contact 3 is at the same level, along the second direction z, as the arms 221 of the return loops 22. And the bases 20 of the return loops 22 are lower than the second movable electrical contacts 3 and therefore than the arms 221 of the return loops 22. The connection supports 223 are at the same level as the bases 20 along the second direction z.

[0069] In the open position of the switching device 1 illustrated in Figures 5 and 6, each bar forming a second movable electrical contact 3 is located above, in the second direction z, the arms 221 of the return loops 22. In the second direction z, the arms 221 of the return loops 22 are located between the second contacts electric 3 mobiles and the bases 20, the connection supports 23 remaining at the same height as the bases 20.

[0070] The carriage 4 illustrated in Figures 1, 2, 5, and 6 comprises a channel 40 for each movable second electrical contact 3. In the illustrated embodiment, the carriage 4 thus comprises three channels 40 extending along the first direction x and passing completely through the carriage 4. Each movable second electrical contact 3 thus passes through the carriage 4 along the first direction x. Each channel 40 is separated from an adjacent channel by an electrically insulating partition 42. Each movable second electrical contact 3 is thus electrically isolated from the other movable second electrical contacts 3.

[0071] Each channel extends over a height along the second direction z sufficient to insert a second movable electrical contact 3 and to obtain a wear stroke necessary for the operation of the product.

[0072] To move the switching device 1 from its closed position to the open position, the switching device 1 comprises an actuator 50 coupled to an actuation column 45 of the carriage 4, the actuator 50 being located under the bases 20 of the first fixed electrical contacts 2 and the actuation column 45 extending vertically, i.e. in the second direction z, of the carriage 4, between the carriage 4 and the actuator 50.

[0073] To move the cut-off device 1 from its closed position to the open position, the actuator 2212 pushes the actuating column 45 upwards, which drives the carriage 4 and the second movable electrical contacts 3 housed in the channels 40, thus breaking any contact between the connection terminals 32 and the axial protrusions 225 of the connection support 223.

[0074] The carriage 4 may include at least one pressure spring inside each channel 40 to apply contact pressure between the second movable electrical contact 3 and the first fixed electrical contact 2.

[0075] In addition, as illustrated in Figures 1 and 5, the cutting device 1 also includes cutting chambers 5 and an external housing 6.

[0076] Each breaking chamber 5 is disposed on the second end 224 of the return loops 22. Each breaking chamber 5 forms an enclosure around a connection support 223 and the end of the second movable electrical contacts 3 carrying the connection terminal 32. Each breaking chamber 5 is configured to absorb an electric arc and dissipate it when it forms between a connection terminal 32 and the axial protrusion 225 of a connection support 223 at the opening of the breaking device 1.

[0077] The switching device 1 is thus designed so that the connections between the second movable electrical contacts 3 and the first fixed electrical contacts 2 are on the outside of the switching device 1 along the first direction x. These are These connections are conducive to the generation of an electric arc when the cutting device 1 is opened. Their positioning on the outside offers a favorable arc starting point when the arc appears, since it is already on the outside of the cutting device 1 and will be attracted outwards into the cutting chamber 5, which can then quickly absorb it.

[0078] The external housing 6 forms an enclosure inside which all the elements of the switching device 1 are mounted, only the connection portions 240 of the connection feet 24 of the first fixed electrical contacts 2 extending outside the external housing 6.

[0079] Figures 1 and 6 are cross-sectional views along a plane comprising the first direction x and the second direction z.

[0080] Figures 8 and 9 show cross-sectional views of a first fixed electrical contact 2 and a second movable electrical contact 3, respectively in a closed position and in an open position. The sections are made in a plane orthogonal to the first direction x, in other words, in a plane comprising the second direction z and the third direction y.

[0081] The direction of the current flowing within the second movable electrical contacts 3, the arms 221, and the base 20 is represented by a point inside a circle when the current exits the figure, and by a cross inside a circle when it enters the figure. A current represented by a point inside a circle and a current represented by a cross inside a circle therefore flow in opposite directions.

[0082] As illustrated in Figures 8 and 9, the currents flowing in the base 20 and in the second movable electrical contacts 3 go in the same first direction, out of the figures, while the currents flowing in the arms 221 of the return loop 22 go in the same second direction, in the figure, opposite to the first direction.

[0083] These directions of current flow in the base 20 and the second mobile electrical contacts 3 generate attractive forces between the base 20 and the second mobile electrical contacts 3 represented by arrows A oriented according to the direction and sense of the force exerted.

[0084] This direction of current flow between the arms 221 and the second mobile electrical contacts 3 generates repulsive forces between the arms 221 and the second mobile electrical contacts 3 represented by arrows R oriented according to the direction and sense of the force exerted.

[0085] As illustrated in [Fig. 8], when the shut-off device 1 is closed, the repulsive forces F are exerted only along the third direction y and therefore do not affect the attraction along the second direction z between the base 20 and the second 3 mobile electrical contacts.

[0086] On the other hand, and as illustrated in [Fig.9], when the switching device 1 is open, the repulsive forces F include a component along the second direction z which tends to push the second mobile electrical contacts 3 away from the base 20 of the first fixed electrical contact 2, thus favoring the opening of the switching device 1.

[0087] In other words, according to the rules of electromagnetism physics, the second mobile electrical contacts 3 are attracted towards the base 20 of each of the first contacts 2 when the switching device 1 is in the closed position, the Laplace forces implemented compensating the repulsive forces generated on the contact surfaces; whereas the second mobile electrical contacts 3 are repelled from the base 20 of each of the first fixed electrical contacts 2 as soon as the switching device 1 leaves its closed position to pass into an open position.

[0088] Figures 10 and 11 schematically represent perspective views of a cutting device 10 according to a second embodiment of the invention, [Fig. 10] representing the cutting device 10 in the closed position and [Fig. 11] representing the cutting device 10 in the open position.

[0089] The second embodiment of the invention differs from the first embodiment illustrated in Figures 1, 2, 5 and 6 in that it comprises only one second movable electrical contact 2 and in that there is only one first fixed electrical contact 2 which is a current return contact.

[0090] The other first fixed electrical contact 2 is a fixed support 200 comprising a connecting foot 24 and a flexible connector 26, but no base 20. The connecting foot 24 comprises a connecting portion 240 and a junction portion 242, the junction portion 242 being disposed between the connecting portion 240 of the connecting foot 24 and the second movable electrical contact 2. The junction portion 242 and the connecting portion 240 are made in one piece. The junction portion 242 of the connecting foot 24 of the fixed support 200 is mechanically and electrically connected to the second movable electrical contact 3 via the flexible connector 26. The flexible connector 26 may be an electrically conductive braid to allow sufficient play for the second movable electrical contact 3 to move from the first position to the second position.

[0091] In this second embodiment, the second movable electrical contact 3 comprises a first end 302 carrying a connection terminal 32 and capable of contacting the connection support 223 of the first fixed electrical contact 2, forming a current-return contact, and a non-free end 306 attached to the fixed support 200 via the flexible connector 26. Furthermore, the second electrical contact 3 mobile no longer performs a simple translation in the second direction z, but it tilts in a plane comprising the second direction z and the first direction x, around a tipping point located between the non-free end 306 of the second electrical contact 3, mobile, and the fixed support 200.

[0092] In a variant of this second embodiment, the switching device could comprise a plurality of second, movable electrical contacts 3.

[0093] Figures 12 and 13 schematically represent perspective views of a cutting device 100 according to a third embodiment of the invention, [Fig. 12] representing the cutting device 100 in the closed position and [Fig. 13] representing the cutting device 100 in the open position.

[0094] The third embodiment of the invention differs from the first embodiment illustrated in Figures 1, 2, 5 and 6 in that it comprises a single second movable electrical contact 3 and in that the first two fixed electrical contacts 2 are placed, along the second direction z, on either side of the second movable electrical contact 3.

[0095] The first two fixed electrical contacts 2 are both current return contacts according to the invention, but are reversed relative to each other along the second direction z while being separated along the first direction x.

[0096] In other words, if we consider one of the first fixed electrical contacts 2 and impose on it a first symmetry with respect to the plane comprising the first direction x and the third direction y, and located in the plane of the base 20, then a second symmetry with respect to a plane comprising the second direction x and the third direction y and located in the middle of the space separating the two first fixed electrical contacts 2, it finds itself in the position of the other first fixed electrical contact 2.

[0097] In this third embodiment, the second movable electrical contact 3 comprises, along the second direction z, a connection terminal 32 oriented in a first direction and a connection terminal 32 oriented in a second direction opposite to the first. The second movable electrical contact 3 moves from a first position to a second position to open the breaking device 100 by pivoting around the center of symmetry of the second movable electrical contact 3, the center of symmetry being an axis extending along the second direction.

[0098] In a variant of this third embodiment, the switching device could comprise a plurality of second, movable electrical contacts 3.

[0099] The invention thus provides a pressure-activated electrical contact switching device comprising a current loop enabling the generation of significant electrodynamic forces to compensate for the repulsive forces present at the electrical contacts in the closed position, while also enabling the generation of forces electrodynamics which tend to open the moving contact when opening under load or overcurrent.

[0100] In addition, the cutting device according to the invention guarantees a cutting arc management physics which allows a high cutting power to be addressed, in particular by electrodynamic forces at the level of the arc feet which tend to drive the arc away from the electrical contacts.

Claims

Demands

1. Switching device (1, 10, 100) comprising two first fixed electrical contacts (2) separated from each other in a first direction (x) and at least one second movable electrical contact (3) in at least a second direction (z) perpendicular to the first direction (x) between a first position in which it is in contact with the first two fixed electrical contacts (2) and a second position in which it is out of contact with at least one of the first two fixed electrical contacts (2), at least one of the first fixed electrical contacts (2) being a current-return contact comprising a base (20) and a return loop (22), the return loop (22) comprising a connection support (223) and at least one arm (221) electrically and mechanically connected between the base (20) and the connection support (223),said at least one arm (221) conducting the current along the first direction (x) and in a direction opposite to the current flowing in the base (20) and to the current flowing in said at least one second electrical contact (3) when it is in the first position, said at least one second electrical contact (3) extending parallel to the base (20) in the first direction (x) and above the base (20) in the second direction (z), and being in direct electrical contact only with the connection support (223) of the return loop (22) when it is in the first position, characterized in that said at least one arm (221) of the return loop (22) is disposed, in the third direction (y), at a distance from said at least one second electrical contact (3).

2. Disconnecting device (1, 10, 100) according to claim 1, wherein, along said first direction (x), the base (20) extends between a first end (202) and a second end (204), and said at least one arm (221) extends between a third end (222) connected to the second end (204) of the base (20) and a fourth end (224) connected to the connection support (223), said at least one arm (221) being in electrical contact with the base (20) only by its third end (222).

3. Disconnecting device (1, 10, 100) according to claim 2, wherein the connection support (223) comprises a protrusion axial (225) extending along the first direction (x) projecting outwards, opposite the base (20), and said at least one second electrical contact (3) extending along the first direction (x) between a fifth end (302) and a sixth end (304), the fifth end (302) comprising a connection terminal (32) in electrical contact with the axial protrusion (225) of the connection support (223) when said at least one second electrical contact (3) is in the first position.

4. Breaking device (1, 10, 100) according to claim 3, further comprising, for each current return contact, a breaking chamber (5) formed around the axial protrusion (225) of the connection support (223) and the connection terminal (32) of said at least one second electrical contact (3) cooperating with the connection support (223).

5. Switching device (1, 10, 100) according to any one of claims 1 to 4, comprising several movable second electrical contacts (3) arranged parallel to each other above the base (20), each movable second electrical contact (3) being spatially separated from the adjacent second electrical contact(s) (3) along the third direction (y).

6. Disconnecting device (1, 10, 100) according to any one of claims 1 to 5, wherein the return loop comprises two arms (221), the two arms (221) being arranged, along the third direction (y), on either side of said at least one second electrical contact (3), and on either side of said base (20).

7. Disconnecting device (1, 10, 100) according to any one of claims 1 to 6, wherein said at least one arm (221) of the return loop (22) is disposed, along the second direction (z), between the base (20) and said at least one second contact (3) when the latter is in the second position.

8. Switching device (1, 10, 100) according to any one of claims 1 to 7, wherein said at least one arm (221) of the return loop (22) is disposed, along the second direction (z), at the same height as said at least one second contact (3) when the latter is in the first position.

9. A disconnecting device (1, 10, 100) according to any one of claims 1 to 7, wherein said at least one arm (221) of the return loop (22) is positioned, along the second direction (z), at the same height as the base (20).

10. Switching device (1) according to any one of claims 1 to 9, further comprising a carriage (4) made of electrically insulating material, the carriage (4) comprising at least one channel (40) passing through the carriage (4) in the first direction (x) and through which is inserted a second electrical contact (3), the carriage (4) being movable in said second direction (z) and driven by an actuator (50), and said at least one second electrical contact (3) being driven in motion in said second direction (z) by the carriage (4).

11. Cutting device (1) according to claim 10, wherein the carriage (4) further comprises at least one pressure spring inside said at least one channel (40).

12. Switching device (100) according to claim 9, wherein the first two electrical contacts (2) are placed, along the second direction (z), on either side of said at least one second electrical contact (3), and said at least one second electrical contact (3) describes a rotational movement in a plane comprising said first direction (x) and said second direction (z) between the first position and the second position.

13. Switching device (1, 100) according to any one of claims 1 to 11, wherein the first two electrical contacts (2) are current return contacts, and said at least one second electrical contact (3) comprises a connecting terminal (32) in contact with one of the first two electrical contacts (2) and a connecting terminal (32) in contact with the other first electrical contact (2).

14. Switching device (10) according to any one of claims 1 to 9, wherein only one of the first electrical contacts (2) is a current return contact, the other first electrical contact (2) comprising an electrically conductive fixed support electrically and mechanically connected to said at least one second electrical contact (3) via a mechanically flexible linkage enabling said at least one second electrical contact (3) to move from the first position to the second position.

Citation Information

Patent Citations

  • Electrical contactor

    EP3979279A1

  • Electric switch having enhanced fault current capability

    US4467301A

  • Contact system for switch

    CN107946098A

  • current-limiting circuit breaker

    DE10121052A1

  • Electrical circuit breaker

    DE102010036215A1