Current switching devices

Abstract

The current switching device (2) comprises a switching element (4) and an actuator (6), each of which comprises a fixed electrical contact (8) and a movable part with a movable electrical contact (12), the movable part being movable along a displacement axis (X) between an open position and a closed position, the actuator (6) comprising a movable part (32), the movable part (32) being movable along the axis (X) so as to move the movable part between its open position and its closed position. Each movable part comprises: a body defining a housing and a holder containing a support bearing the movable contact (12), the holder being mounted in the housing and being movable along the axis (X) relative to the movable part. A movable end stop movable along the axis (X) by means of an adjusting screw limits the movement of the holder relative to the body.

Description

Technical Field

[0001] The invention relates to a current switching device. Background Art

[0002] In the field of current switching devices such as contactors, WO 2014 / 096582 A1 describes a multi-pole switching device comprising a plurality of switching elements with separable contacts, each switching element being associated with a multi-phase current and being connected to an actuator that simultaneously moves the separable contacts between an open position and a closed position. In the closed position, the movable contacts of the switching elements are in contact with the corresponding fixed contacts, which allows the passage of current. In the case of a three-phase current, the switching device comprises three switching elements. In this case, each switching element is associated with a phase of the current.

[0003] WO-2014 / 096582-A1 describes in particular means for adjusting the position of each switching element in the vicinity of the closed position so that the mechanical synchronization of the fixed pad and the movable pad of each switching element is as optimal as possible between all the switching elements of the unit. In practice, in the closed position, there may be misalignments between the movable contacts relative to their theoretical ideal position, which is generally due to dimensional tolerances caused by the variability inherent in the unit manufacturing method.

[0004] This misalignment results in an uneven squeezing of the contacts of one switching element to the contacts of the other switching element in the closed position. For example, the movable contact of a first switching element may be in an advanced position than the movable contact of a second switching element of the same unit. Such a misalignment may produce uneven wear of the electrical contacts within the unit. However, in some cases, it is difficult to adjust the position precisely, especially because the position adjustment is only possible when the movable contact is in the open position. Summary of the invention

[0005] The invention particularly addresses these problems by proposing a novel current switching device comprising switching elements, each of which comprises, on the one hand, a fixed part connected to a fixed electrical contact and, on the other hand, a movable part carrying a movable electrical contact, the movable part being movable in translation along a movement axis between an open position and a closed position of the electrical contact, the current switching device also comprising an actuator comprising a movable part movable in translation along the movement axis in order to move the movable part between an open position and a closed position, for which purpose each movable part comprises a connecting member fixed to the movable part.

[0006] Furthermore, each movable part of the switching device comprises a body comprising a first housing, and each switching element comprises, on the one hand, a holder mounted in the first housing, connected to a support carrying the movable contact, the holder being movable in translation relative to the movable part along an axis of movement, and each switching element comprises, on the other hand, a movable end stop limiting the movement of the holder relative to the movable part, the movable end stop being movable in translation along the axis of movement by means of an adjusting screw.

[0007] By means of the invention, the adjustment of the alignment between the switching elements is simpler and more accurate. The adjustable movable end stop makes it possible to control the movement of the retainer independently of the body of the movable part, which makes it possible to fine-tune the position of the movable contact in the closed position to compensate for possible misalignment with other movable contacts when the other movable contacts are in the closed position.

[0008] This adjustment thus makes it possible to extend or reduce the translational travel of each movable contact in a controlled manner.This adjustment can be performed for each switching element independently of the other switching elements, even if these switching elements are all connected to the same movable part of the actuator.

[0009] On the other hand, in WO-2014 / 096582-A1, the stroke is adjusted by extending or shortening the connecting member that fixes the movable part to the movable contact. Therefore, as long as the movable part of the actuator is connected to the movable part, it is impossible to adjust the stroke.

[0010] Furthermore, when the movable part is disconnected to provide access to the connecting member, it is no longer possible to accurately know the true closed position, since this is imposed on the contacts by the connecting member.

[0011] According to an advantageous but non-mandatory aspect of the invention, such a switchgear may comprise one or more of the following features, in any technically acceptable combination:

[0012] The head of the adjusting screw is arranged in the movable portion along the movement axis opposite to the connecting member.

[0013] - The movable end stop is a flange incorporated in the shank of the adjusting screw, said flange being rotationally fixed with the shank.

[0014] The holder comprises a rear face at right angles to the movement axis, the movable end stop being arranged inside the first housing behind the rear face to prevent the holder from retracting when the movable part reaches the open position.

[0015] - Each switching element comprises a washer arranged between the head of the adjusting screw and the rear wall of the body of the movable part.

[0016] The holder defines a second housing in which the support is mounted, the support being movable translationally relative to the holder in the second housing along the movement axis, and the holder comprising an elastic return member arranged in the second housing which returns the support towards the fixed contact.

[0017] At least one side surface of the retaining frame comprises a first relief intended to cooperate, by complementarity of shape, with a second relief present on the inner face of the first housing, in order to retain and guide the retaining frame in translation relative to the body of the movable part.

[0018] - The holder is made of plastic material.

[0019] - the unit is a multi-pole switching device suitable for interrupting a multi-phase current, the switching device comprising a plurality of switching elements, each switching element being associated with a phase of the current. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The invention will be better understood and other advantages of the invention will become more apparent from the following description of several embodiments of the switchgear, which are given by way of example only and with reference to the accompanying drawings, in which:

[0021] - Figure 1 is a schematic cross-sectional view of a switchgear according to an embodiment of the present invention;

[0022] - Figure 2 yes Figure 1 A schematic exploded view of the movable part of the switchgear;

[0023] - Figure 3 yes Figure 2 A partial cross-sectional view of the movable part of the switchgear;

[0024] - Figure 4 yes Figure 2 and 3 A front view of the movable part of the embodiment of the present invention, wherein the adjusting screw is loosened and the cage is translated backward;

[0025] - Figure 5 yes Figures 2 to 4 Front view of the movable part, where the adjusting screw is tightened and the cage translates forward. DETAILED DESCRIPTION

[0026] Figure 1 The current switching device 2 shown in FIG. 1 includes a Figure 1A plurality of switch elements 4 are juxtaposed in a direction at right angles to the plane of the current switch 2, of which only one switch element is visible in the figure, referenced 4. The current switching device 2 also includes an actuator 6 common to the different switch elements 4. The switch element 4 is sometimes referred to as a "switch block" or "switch bulb".

[0027] The current switching device 2 makes it possible to interrupt or alternatively allow the flow of electric current, for example in response to a control voltage.Such a switching device is for example intended to be installed in an electrical device, in particular in an electrical cabinet.

[0028] The current switching device 2 is for example a multi-pole unit with separable contacts, which is suitable for interrupting a multi-phase current. In this case, each switching element 4 is associated with a phase of the current. In the embodiment illustrated in the drawings, the unit is suitable for interrupting a three-phase current and comprises three switching elements 4.

[0029] The three switching elements 4 are identical here, but only one of them will be described in detail below.

[0030] Each switching element 4 comprises a fixed contact 8 connected to a connection plate 10 upstream and downstream of the unit 2 and a movable contact 12 reversibly movable relative to the fixed contact 8 between an open position and a closed position, here along an axis of movement X.

[0031] The fixed contacts 8 each include a fixed contact pad 14 , and the movable contact 12 includes a movable contact pad 16 .

[0032] When the fixed contact 8 fixed to the connection plate 10 is separated from the movable contact 12, the circulation of current in the switch element 4 is interrupted. When these contacts are separated, the fixed contact pad 14 carried by the fixed contact 8 is not in contact with the movable contact pad 16 carried by the movable contact 12. This first configuration corresponds to an open position of the movable contact 12, in which the current does not flow.

[0033] Conversely, the closed position of the movable contact 12 corresponds to a situation in which the movable contact pad 16 abuts against the fixed contact pad 14 , thus allowing the circulation of electric current in this second configuration.

[0034] The switch elements 4 are each equipped with a movable part 20 . A connecting member 30 ensures the coupling of the movable part 20 of each switch element 4 to the actuator 6 . The simultaneous movement of the movable contacts 12 between the open position and the closed position is caused by the movable part 32 of the actuator 6 .

[0035] The actuator 6 here includes an electromagnet and a movable part 32 which are not labeled in the figure. For example, the movable part 32 includes a magnetic material. When the electromagnet is powered after receiving a control voltage, it exerts a magnetic force that drives the movable part 32 to translate along the X axis to the closed position. Conversely, when the electromagnet is de-powered, the movable part 32 returns to the open position.

[0036] For example, the actuator 6 is mounted in the front part of the unit 2. For the purpose of explanation, the front part and the rear part of the unit 2 are defined below with reference to the movement of the movable contact 12 along the axis X. Figure 1 , arrow F1 indicates the moving direction of the movable member 32 and the movable contact 12 from the back to the front of the unit 2.

[0037] The movable part 32 makes it possible to move each movable part 20 of each switch element 4 simultaneously along the movement axis X. The movement of the movable part 32 along the movement axis X drives the movement of each movable part 20 along the same movement axis X through the connecting member 30 of each switch element 4, thus producing a transition from the open position to the closed position (or vice versa). Therefore, this movement of the movable part 20 of the switch element 4 has the effect of bringing the movable contact pad 16 carried by the movable contact 12 into contact with the fixed contact pad 14 carried by each fixed contact 8.

[0038] The movable part 20 is Figure 2 and 3 The movable part 20 comprises a body 22 fixed to a connecting member 30 and a holder 24 to which a movable support 26 carrying the movable contact 12 is connected. The movable support 26 is also referred to as a "movable bridge". In the following, the expression "movable bridge" is used.

[0039] In this embodiment, the body 22 includes a hollow portion forming a first housing 34 defined by side walls 36 and 38, a front wall 41, and a rear wall 40. The holder 24 is accommodated in the first housing 34.

[0040] The cage 24 is preferably rectangular and comprises a front face 48, a rear face 46 and two side faces 50 and 52. The rear face 46 is at right angles to the axis X of movement.

[0041] In this example, the faces 46, 48, 50 and 52 of the cage 24 delimit a second housing 44 intended to house the movable bridge 26 and the elastic return member 28. The elastic return member 28 is, for example, a compression helical spring.

[0042] The elastic return member 28 allows movement along the axis of movement X of the movable bridge 26 relative to the cage 24 .

[0043] The elastic return member 28 returns the movable bridge 26 toward the fixed contact 8 and makes it possible to buffer the impact received by the movable contact 12 when the movable contact pad 16 comes into contact with the fixed contact pad 14 when the switch element 4 is closed.

[0044] The movable bridge 26 is movable in translation relative to the holder 24 along a movement axis X. The holder 24 is movable in translation relative to the body 22 along the same movement axis X. However, the translation of the holder 24 relative to the body 22 is separated from the translation of the movable bridge 26 relative to the holder 24. In other words, these two translations are independent of each other.

[0045] According to a variant that is not shown, the movable bridge 26 could remain fixed to the holder 24 and the elastic return member 28 could then be omitted.

[0046] The switch element 4 further comprises a movable end stop 60, which is arranged here between the rear face 46 of the holder 24 and the rear wall 40 of the body 22. In other words, the movable end stop 60 is arranged inside the first housing 34, behind the rear face 46.

[0047] When the movable part 20 reaches the open position, the movable end stop 60 is movable in translation along the movement axis X and limits the retraction of the cage 24 .

[0048] In this embodiment, the movable end stop 60 is fixed to an adjustment screw 62 .

[0049] The adjusting screw 62 here comprises a head 64 and a shank 66. The hole 42 (preferably tapped) through the rear wall 40 of the body 22 and the aperture 54 through the rear face 46 of the holder 24 accommodate the shank 66 of the adjusting screw 62. Both the hole 42 and the aperture 54 are coaxial with the axis of movement X.

[0050] For example, the shank 66 thus forms a preferably screw connection with the hole 42. Here, this screw connection allows the movable end stop 60 to be moved along the displacement axis X.

[0051] The head 64 of the adjusting screw 62 is located outside the body 22 , opposite the connecting member 30 along the axis X. In other words, the head 64 extends beyond the rear wall 40 of the body 22 to be accessible from the outside so as to be actuated by a tool 80 such as a screwdriver.

[0052] In this embodiment, the movable end stop 60 is a flange added to the shank 66 of the adjusting screw 62 so as to be rotationally fixed with the shank 66 when the shank 66 rotates about the axis X. The flange may take the form of a disk centered on the axis X of movement.

[0053] In order to limit the movement of the holder 24 relative to the body 22, the flange of the movable end stop 60 can be moved closer to the rear face 46 of the holder 24. When the tool 80 rotates the adjustment screw 62 to the tightening state, a translation occurs along the movement axis X from the back to the front of the movable end stop 60, which drives the translation of the holder 24 along the movement axis X relative to the body 22.

[0054] On the other hand, as long as the adjustment screw 62 is not turned by the tool 80 , the movable end stop 60 remains stationary, for example, because the threads of the shank 66 engage the tapping of the hole 42 .

[0055] When the adjustment screw 62 is in a relaxed state, the movable end stop 60 is in a position retracted to the rear of the unit 2. The holder 24 is not pressed by the movable end stop 60 and is held in the advanced position, and the holder 24 is then in a "floating" position.

[0056] When the fixed contact 8 meets the movable contact 12, the retainer 24 is brought from the front to the back to abut against the movable end stop 60, and the retainer 24 is then in the retracted position. The exact position of the retainer 24 can then be adjusted, for example, by means of a tool 80 using the adjusting screw 62, in order to compensate for any misalignment with the movable contact 12 of the other switch element 4.

[0057] exist Figure 4 and 5 Two possible positions of the movable end stop 60 are shown in FIG. Figure 4 The spacing e1 and Figure 5 The spacing e2 in this case corresponds to the distance between the inner face of the front wall 41 of the body 22 and the front face 48 of the holder 24 when the holder 24 abuts against the movable end stop 60 .

[0058] As an illustrative example, the distances e1 and e2 are here in the range of 0.1 mm and 1 mm, respectively.

[0059] exist Figure 4 In the configuration shown, the spacing e1 is greater than Figure 5 The spacing e2.

[0060] To switch from the spacing e1 to the spacing e2, the holder 24 is translated from the rear to the front of the current switching device 2. The translation of the holder 24 by the end stop 60 and the adjusting screw 62 makes it possible to bring the movable bridge 26 closer to the actuator 6, which is equivalent to accurately adjusting the position of the movable contact 12 fixed to the movable bridge 26 relative to the fixed contact 8.

[0061] The switching element 4 is preferably adjusted into the closed position.

[0062] The translation of the movable end stop 60 along the movement axis X makes it possible to control the movement of the cage 24 independently of the body 22 of the movable part 20. This therefore makes it possible to finely adjust the position of the movable contact 12 in the closed position to compensate for possible misalignments of the movable contact 12 with the other movable contacts 12 when they are in the closed position.

[0063] In other words, the translational travel of each movable contact 12 can be extended or reduced in a controlled manner. The adjustment of the translational travel can be performed for each switch element 4 independently of the other switch elements 4 .

[0064] Advantageously, the invention allows adjustment even when all the switch elements 4 are connected to the same movable part 32 of the actuator 6, in contrast to the adjustment described in WO-2014 / 096582-A1, in which the adjustment function is ensured by a screw used simultaneously with the connecting member. The adjustment cannot be made in the closed position but must be made in the open position. Here, on the contrary, the adjustment function and the connection function to the actuator are ensured independently of each other. The connection function between the actuator 6 and the movable contact 12 is separated from the travel adjustment function, which makes it possible to make adjustments in the closed position even when the actuator 6 is mounted on the front of the unit 2.

[0065] Preferably, each switch element 4 comprises a washer 68 which is screwed onto the stem 66 and is interposed between the head 64 and the outer face of the rear wall 40 of the body 22. This washer 68 makes it possible to occupy the space created between the head 64 and the outer face of the rear wall 40 when the spacing between the inner face of the rear wall 40 of the body 22 and the rear face 46 of the holder 24 varies. For example, the washer 68 is made of metal or an elastomeric material.

[0066] According to an optional but not mandatory embodiment, the holder 24 is made of plastic, preferably in the form of a strip. This plastic strip has a folded form to form a rectangular frame. In its folded form, the rear face 46 is at right angles to the axis of movement X. The rear face 46 is adjacent to two side faces 50 and 52. These side faces 50 and 52 are parallel to each other and adjacent to the front face 48 of the holder. The front face 48 and the rear face 46 are parallel to each other. When the folded strip forming the frame consisting of the rear face 46, the side faces 50, the front face 48 and the side faces 52 covers the rear face 46, the rear face 46 is lined.

[0067] Alternatively, the holder 24 may have another form, for example square or cylindrical. The form of the first housing 34 must in each case be suitable for accommodating the holder 24 .

[0068] According to a preferred but non-mandatory embodiment of the invention, at least one of the sides 50 or 52 of the holder 24 comprises a first relief 70 which cooperates, by complementarity of shape, with a second relief 72 present on one of the side walls 36 or 38 of the body 22. Thus, the connection formed by the first relief 70 and the second relief 72 holds the holder 24 in the first housing 34 and guides the holder in translation along the movement axis X.

[0069] In particular, the first relief 70 cooperates with a third relief 74 present on the movable bridge 26 to retain the bridge 26 inside the second housing 44 delimited by the retainer 24 , in particular during assembly operations of the switching element 4 .

[0070] Any feature of one of the above described embodiments or variations may be implemented in the other described embodiments and variations.

Claims

1. A current switching device (2), comprising: - at least one switching element (4), each switching element comprising: a fixed part, which carries the fixed contacts (8), and a movable part (20) carrying the movable contact (12), said movable part being movable in translation along a movement axis (X) between an open position and a closed position of the electrical contact; - an actuator (6) comprising a movable part (32) movable in translation along a movement axis (X) in order to move the movable part (20) between its open position and its closed position, each movable part (32) comprising for this purpose a connecting member (30) fixed to the movable part; The current switching device (2) is characterized in that each movable part (20) comprises a body (22), the body (22) comprises a first housing (34), and each switching element (4) further comprises: - a holder (24) mounted in the first housing (34), said holder (24) being movable in translation along a movement axis (X) relative to the body (22) of said movable part (20), said holder (24) being connected to a support (26) carrying the movable contact (12), and - a movable end stop (60) which limits the movement of the retaining frame (24) relative to the body (22) of the movable part (20), the movable end stop (60) being movable in translation along the movement axis (X) relative to the body (22) of the movable part (20) by means of an adjustment screw (62).

2. The current switching device according to claim 1, characterized in that The head portion (64) of the adjusting screw (62) is arranged in the movable portion (20) along the movement axis (X) opposite to the connecting member (30).

3. The current switching device according to claim 1 or 2, characterized in that: The movable end stop (60) is a flange incorporated in the shank (66) of the adjusting screw (62), the flange being rotationally fixed to the shank (66).

4. The current switching device according to claim 1 or 2, characterized in that: The retaining frame (24) includes a rear face (46) at right angles to the movement axis (X), and the movable end stop (60) is arranged inside the first housing (34) behind the rear face (46) to prevent the retaining frame (24) from retracting when the movable part (20) reaches the open position.

5. The current switching device according to claim 2, characterized in that Each switch element (4) comprises a washer (68) arranged between the head (64) of the adjusting screw (62) and the rear wall (40) of the body (22) of the movable part (20).

6. The current switching device according to claim 1 or 2, characterized in that: The retaining frame (24) defines a second housing (44), the support member (26) is mounted in the second housing (44), the support member (26) can be moved translationally relative to the retaining frame (24) along the movement axis (X) in the second housing (44), and the retaining frame (24) includes an elastic return member (28) arranged in the second housing (44), which returns the support member (26) towards the fixed contact (8).

7. The current switching device according to claim 1 or 2, characterized in that: At least one side surface of the retaining frame (24) includes a first concave-convex portion (70), which is used to cooperate with a second concave-convex portion (72) existing on the inner surface of the first shell (34) through complementarity of shape to retain and guide the retaining frame (24) to translate relative to the main body (22) of the movable part (20).

8. The current switching device according to claim 1 or 2, characterized in that: The retaining frame (24) is made of plastic material.

9. The current switching device according to claim 1 or 2, characterized in that: The current switching device (2) is a multi-pole switching device suitable for interrupting multi-phase currents, the switching device comprising a plurality of switching elements (4), each switching element (4) being associated with a phase of the current.

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