Patent Description:
In particular, the invention concerns an earthing switch or a disconnector of a gas insulated equipment.

<FIG> illustrates the general structure of a switch <NUM> for a gas insulated equipment <NUM>. <CIT> discloses a compressed gas-blast circuit breaker of the prior art.

According to known embodiments, each switch comprises a male arcing contact rod and a piston which are rigidly connected to each other to move in a single motion relative to a second electrical contact.

The piston expels pressurized arc extinguishing gas for blowing out an electric arc formed between the second electrical contact and the male electrical contact when the electrical male contact disengages the second electrical contact.

However, such a known switch is often heavy and cumbersome so that the switch can efficiently blow out the electrical arc. The switch may use an arc extinguishing gas with greenhouse effect such as SF<NUM>.

The invention concerns an electrical connector for a medium or a high voltage gas insulated electrical equipment. The electrical connector comprises a first electrical contact, a mobile body and a fixed body.

The first electrical contact is configured to move axially along a longitudinal direction of the first electrical contact to electrically engage a second electrical contact. The mobile body partially delimits a compression chamber to be filled with an arc extinguishing fluid. The fixed body comprising a wall of the compression chamber, preferably a bottom wall of the compression chamber.

The compression chamber comprises at least an opening through which the arc extinguishing fluid is configured to flow towards an electric arc formed between the first electrical contact and the second electrical contact when the first electrical contact electrically disengages the second electrical contact to blow out the electrical arc.

The mobile body and the fixed body surround the first electrical contact.

According to the invention, the electrical connector comprises an actuation mechanism configured to move the first electrical contact and the mobile body axially with different speeds relative to the fixed body.

Thanks to the electrical connector according to the invention, an arc between the male contact and the female contact can be efficiently blown out with a smaller and lighter male connector. Accordingly, the gas insulated equipment can also be smaller and lighter.

As the electrical arc between the male connector and the female connector is more efficiently blown out by the electrical connector, a less efficient arc extinguishing gas but with less global warming potential can be used, such as a mixture of fluoronitrile, carbon dioxide and dioxygen which is also known as g3 mixture.

The arc extinguishing gas tends to be expelled at a higher speed and/or with a greater pressure when the male contact is sufficiently away from the female contact so that the electrical arc can be efficiently blown out.

Preferably, the electrical connector comprises a nozzle inside the opening of the compression chamber. The nozzle comprises at least a hole for expelling arc extinguishing fluid out of the electrical connector.

The nozzle comprises preferably an annular hole forming a channel around the first electrical contact. The channel most preferably extends from the first electrical contact to a lateral wall of the nozzle surrounding the first electrical contact.

Preferably, the nozzle comprises through holes through an external lateral wall of the nozzle. The through holes are preferably equally angularly spaced around the first electrical contact.

In an embodiment, the channel has a diminishing width towards the outside of the electrical connector.

Alternatively, the channel has a constant width towards the outside of the electrical connector.

In an embodiment, the channel is tapered towards the outside of the electrical connector.

Alternatively, the channel is curved towards the outside of the electrical connector.

In an embodiment, the nozzle has a first channel extending from the first electrical contact to a lateral internal wall of the nozzle surrounding the first electrical contact. The nozzle has a second channel surrounding the first channel and extending from the internal wall to an external lateral wall of the nozzle.

Preferably, the actuation mechanism is configured to move the mobile body relative to the fixed body at a lower speed than the speed of the first electrical contact relative to the fixed body.

The actuation mechanism comprises a disconnecting lever, at least a linking arm connecting the disconnecting lever to the mobile body by at least a first link. The first electrical contact is connected to the disconnecting lever by at least a second link.

The first link and the second link are most preferably pivot link.

The actuation mechanism comprises a rudder through which the first electrical contact is configured to extend and to move axially. An end of the linking arm is fixed to the rudder. The actuation mechanism comprises at least a traction rod extending from the rudder to the mobile body to move the mobile body axially relative to the first electrical contact.

The actuation mechanism comprises a slave connecting rod connecting the first electrical contact to the disconnecting lever by at least a link. Most preferably, the slave connecting rod is connecting the first electrical contact to the disconnecting lever by a pivot link at each longitudinal end of the slave connecting rod.

Preferably, the fixed body comprises a sleeve surrounding the first electrical contact to guide the first electrical contact axially relative to the fixed body.

Preferably, the electrical connector comprises a housing surrounding at least part of the actuation mechanism. The fixed body is integral with or fixed to the housing.

Preferably, the first electrical contact comprises a male arcing contact rod. The mobile body is cylindrical around the longitudinal axis of the male arcing contact rod. The fixed body is annular around the longitudinal axis of the male arcing contact rod.

Most preferably, the nozzle has a generally cylindrical shape around the longitudinal axis of the male arcing contact rod. Most preferably, the nozzle extends radially between the male arcing contact and the mobile body.

The invention also relates to a medium or a high voltage gas insulated electrical equipment comprising a first electrical connector as described above, a second electrical connector and a gas insulated enclosure.

The female electrical connector comprises a second electrical contact, preferably a tulip type electrical contact. The first electrical contact of the electrical connector is configured to electrically engage the second electrical contact.

The gas insulated enclosure surrounds the female electrical connector. The gas insulated enclosure at least partially delimits a cavity forming a gap between the second electrical contact and the first electrical contact when the gas insulated equipment is in an opened position. In the opened position of the gas insulated equipment, the male electrical connector is electrically disconnected from the female electrical connector.

Preferably, the gas insulated electrical equipment wherein the electrical connector is a disconnecting switch or earthing switch for a gas insulated equipment. Most preferably, the gas insulated electrical equipment comprises an electrical connector and an electrical female connector for each phase of an AC electric line.

This invention will be better understood after reading the following description of example embodiments, wherein:.

Identical, similar or equivalent parts of the different figures are marked with the same numbers for facilitating comparisons between the different figures.

<FIG> shows a portion of an AC gas insulated equipment. The gas insulated equipment <NUM> comprises enclosures <NUM> for each phase of the gas insulated equipment <NUM> and a switch <NUM> at least partially inside each enclosure <NUM>. Each enclosure <NUM> is gas insulated. Each enclosure <NUM> is to be filled with an arc extinguishing gas such as mixture of fluoronitrile, fluoroketones, carbon dioxide and /or dioxygen.

The gas insulated equipment <NUM> is supported on the ground by a supporting frame <NUM> having legs.

A drive mechanism <NUM> commonly actuates each switch <NUM> at the same time for switching off current of the three phases. The drive mechanism <NUM> comprises a driver <NUM> and a drive rod <NUM> which is driven by the driver <NUM>.

With reference to <FIG>, the gas insulated equipment <NUM> comprises a first male electrical connector <NUM> and a second high voltage female electrical connector <NUM> for each phase of the equipment <NUM>. The first male electrical connector <NUM> is a switch.

Each female connector <NUM> is entirely located inside a cavity 5b of an enclosure <NUM> of the equipment <NUM>. There is a gap between the female electrical connector <NUM> and a wall 5a of the enclosure towards the male electrical connector <NUM>. The female connector <NUM> is fixed to the enclosure <NUM> of the equipment <NUM>.

The female connector <NUM> comprises a second female electrical contact <NUM> and a support structure 4a for holding the female electrical contact <NUM> inside the enclosure <NUM>.

The female electrical contact <NUM> is a tulip type electrical contact comprising a plurality of electrical contact fingers <NUM> and a base <NUM> holding the electrical contact fingers <NUM>.

The female electrical contact <NUM> is configured to electrically engage a male electrical contact <NUM> when the earthing switch <NUM> is in a closed position. In particular, the electrical contact fingers <NUM> are configured to grasp a conductive head 20b of the male electrical contact <NUM> when the earthing switch <NUM> is in a closed position.

The earthing switch <NUM> comprises a male electrical contact <NUM>, a mobile body <NUM>, a fixed body <NUM>, a housing <NUM>, a nozzle <NUM>, and an actuation mechanism <NUM>. The male electrical connector <NUM> is for example an earthing switch of a phase of the AC equipment <NUM>.

The housing <NUM> surrounds most of the actuating mechanism <NUM>. It protrudes at least partially from the enclosure <NUM> to which it is fixed by a flange.

The male electrical contact <NUM>, the mobile body <NUM>, the fixed body <NUM>, the nozzle <NUM> and the actuation mechanism <NUM> are configured to be located at least partially inside the enclosure <NUM> and inside the housing <NUM>. The fixed body <NUM> may be fixed or integral with the housing <NUM>.

The male electrical contact <NUM>, the nozzle <NUM>, the mobile body <NUM> and the fixed body <NUM> are each annular along a longitudinal direction X-X of the male electrical contact <NUM>. The nozzle <NUM>, the mobile body <NUM> and the fixed body <NUM> each surround the male electrical contact <NUM>.

The male electrical contact <NUM> is a male arcing contact rod in the disclosed embodiments. The male arcing rod <NUM> comprises a shank 20a and a head 20b which is at an end of the shank 20a along a longitudinal direction X-X of the male arcing rod <NUM>.

The male electrical contact <NUM> is configured to electrically engage the female electrical contact <NUM>, when the grounding switch <NUM> is in a closed position. The male electrical connector <NUM> is configured to be electrically disconnected from the female electrical contact <NUM> when the grounding switch <NUM> is in an opened position.

The male electrical contact <NUM> is configured to move in translation axially along the longitudinal direction X-X of the male electrical contact <NUM> relative to the housing <NUM> and to the fixed body <NUM> to electrically engage the female electrical contact <NUM>.

The mobile body <NUM> has a lateral wall 22a which is cylindrical around the longitudinal axis X-X of the male arcing contact rod. The mobile body <NUM> also comprises an upper wall <NUM> at one axial end of the lateral wall 22a nearest to the female contact <NUM>. There is a central opening 22b in the upper wall <NUM> around the male electrical contact <NUM>.

The mobile body <NUM> partially delimits with the fixed body <NUM> a compression chamber <NUM> to be filled with an arc extinguishing gas.

The mobile body <NUM> is configured to move in translation axially along the longitudinal direction X-X of the male electrical contact <NUM> both relative to the male electrical contact <NUM> to the fixed body <NUM>.

The mobile body <NUM> acts as a piston expelling arc extinguishing gas out of the compression chamber <NUM> when the mobile body <NUM> moves axially opposite to the female electrical contact <NUM>.

The fixed body <NUM> comprises a bottom wall <NUM> of the compression chamber <NUM> and a sleeve <NUM> surrounding the male electrical contact <NUM>.

The bottom wall <NUM> closes the compression chamber <NUM> axially opposite to the upper wall <NUM> of the mobile body <NUM>. The bottom wall <NUM> is at an axial end of the fixed body <NUM> closer to the female electrical contact <NUM>.

The sleeve <NUM> is configured to guide the male electrical contact <NUM> axially relative to the fixed body <NUM>.

The compression chamber <NUM> comprises at least an opening through which the arc extinguishing gas is configured to flow towards an electric arc formed between the male electrical contact <NUM> and the female electrical contact <NUM> when the earthing switch <NUM> is opening.

In the first embodiment disclosed in <FIG>, the compression chamber <NUM> is able to be in fluid communication with the outside of the male electrical connector <NUM> through a first channel <NUM> around the male electrical contact <NUM> in a first intermediate opened position of the earthing switch <NUM> or by through holes <NUM> of the nozzle <NUM> when the earthing switch <NUM> is opened in a second intermediate opened position.

The nozzle <NUM> has a cylindrical shape around the longitudinal axis X-X of the male electrical contact <NUM>. The nozzle <NUM> extends radially between the male electrical contact <NUM> and the mobile body <NUM> through the central opening 22b of the mobile body <NUM>. The nozzle <NUM> has a central orifice <NUM> configured to surround the male electrical contact <NUM>.

The nozzle <NUM> delimits at least partially at least a channel <NUM> to conduct arc extinguishing gas towards the female electrical contact <NUM> when the earthing switch <NUM> is opening. The channel <NUM> extends from the male electrical contact <NUM> to a lateral wall <NUM>, <NUM> of the nozzle <NUM> surrounding the male electrical contact <NUM>.

In the first disclosed embodiment with reference to <FIG>, the nozzle <NUM> comprises a first channel 51a and a second channel <NUM> surrounding the first channel 51a. The first channel 51a extends from the male electrical contact <NUM> to an internal lateral wall <NUM> of the nozzle <NUM> surrounding the male electrical contact <NUM>.

The second channel <NUM> surrounds the first channel 51a and extends from the internal lateral wall <NUM> to an external lateral wall <NUM> of the nozzle <NUM>.

The nozzle <NUM> comprises through holes <NUM> through the external lateral wall <NUM> of the nozzle <NUM>. The through holes <NUM> are preferably equally angularly spaced around the male electrical contact <NUM>. They are in fluid communication with the second channel <NUM> when the male electrical contact <NUM> is sufficiently retracted into the housing <NUM> when the switch <NUM> is opening.

The actuation mechanism <NUM> comprises an entrance gear <NUM>, a disconnecting lever <NUM>, a slave connecting rod <NUM>, two linking arms <NUM>, a rudder <NUM> and traction rods <NUM>.

The actuation mechanism <NUM> is configured to move the male electrical contact <NUM> and the mobile body <NUM> axially with different speeds relative to the fixed body <NUM>. More precisely, the actuation mechanism <NUM> is configured to move the mobile body <NUM> relative to the fixed body <NUM> at a lower speed than the speed of the male electrical contact <NUM> relative to the fixed body <NUM>.

The entrance gear <NUM> is mechanically coupled to the drive mechanism <NUM>. The entrance gear <NUM> is configured to rotate the disconnecting lever <NUM> when it is driven in rotation by the drive command rod <NUM> of the drive mechanism <NUM>.

The disconnecting lever <NUM> is a lever arm having a first longitudinal end coupled to the entrance gear <NUM>. The disconnecting lever <NUM> has a second longitudinal end opposite to the first longitudinal end wherein the disconnecting lever <NUM> is coupled to the male electrical contact <NUM> through the slave connecting rod <NUM>.

With reference to <FIG> and <FIG>, the disconnecting lever <NUM> is configured to pivot from a first position closer to the female electrical contact <NUM> when the switch <NUM> is in a fully opened position to a second position farther from the female electrical contact <NUM> when the switch <NUM> is in a fully closed position.

The slave connecting rod <NUM> is connecting the male electrical contact <NUM> to the disconnecting lever <NUM> by a second link <NUM> and a third link <NUM>. The slave connecting rod <NUM> is configured to have a rotation movement following the rotation of the disconnecting lever <NUM> and to move with an axial movement by moving the male electrical contact <NUM> axially.

The second link <NUM> is a pivot link between the slave connecting rod <NUM> and the disconnecting lever <NUM>. The second link <NUM> is at a first longitudinal end of the slave connecting rod <NUM> and a second longitudinal end of the disconnector lever <NUM>.

The third link <NUM> is a pivot link between the male electrical contact <NUM> and the slave connecting rod <NUM>. The third link <NUM> is at a second longitudinal end of the slave connecting rod <NUM> and a first longitudinal end of the male electrical contact <NUM> opposite to the head 20b of the male electrical contact <NUM>.

The linking arms <NUM> both connect the disconnecting lever <NUM> to the mobile body <NUM> by a first link <NUM> and they are fixed to a rudder. The linking arm <NUM> connect the disconnecting lever <NUM> to the rudder <NUM> to move the rudder <NUM> axially when the disconnecting lever <NUM> is pivoting.

The first link <NUM> is a pivot link between the disconnecting lever <NUM> and each of the linking arms <NUM>. The first link <NUM> is at a first longitudinal end of the disconnecting lever <NUM> and at a first longitudinal end of each of the linking arms <NUM>.

The linking arm <NUM> are each fixed to the rudder <NUM> at a second longitudinal end of the linking arms opposite to the first longitudinal end of the linking arms <NUM>.

The rudder <NUM> comprises a central hole through which the male electrical contact <NUM> extends and through which the male electrical contact <NUM> is configured to move axially, e.g. by sliding. The linking arms <NUM> are fixed to the rudder <NUM> near the central hole. The rudder <NUM> is configured to guide axially together with the fixed body <NUM> the male electrical contact <NUM> and the mobile body <NUM>.

The actuation mechanism <NUM> comprises two traction rods <NUM> which are fixed to the rudder <NUM> at a longitudinal end of the rudder <NUM>. The traction rods <NUM> may also be integral with the rudder <NUM>.

A first longitudinal end of the traction rods <NUM> is fixed to the rudder. A second longitudinal end of the traction rods <NUM> opposite to the first longitudinal end is fixed to the upper wall <NUM> of the mobile body <NUM>. The traction rods <NUM> extend each parallel to the male arcing contact rod <NUM>.

The traction rods <NUM> are each configured to move in translation along the longitudinal direction X-X of the male electrical contact <NUM> to move the mobile body <NUM> axially relative to the male electrical contact <NUM>. The traction rods <NUM> are configured to pull the mobile body <NUM> axially relative to the fixed body <NUM> and to the housing <NUM> when the switch <NUM> is opening.

A method <NUM> of electrically disconnecting the male electrical connector <NUM> from the female electrical connector <NUM> is illustrated with reference to <FIG>.

With reference to <FIG>, the switch <NUM> is in fully closed position. The male electrical connector <NUM> is electrically connected to the female electrical connector <NUM>. The conductive head 20b of the male electrical connector <NUM> is grasped by the electrical fingers <NUM> of the female electrical contact <NUM>. An arc extinguishing gas is in the compression chamber <NUM> at a pressure which is similar to the pressure in the cavity 5b.

With reference to <FIG>, the switch <NUM> is in an intermediate closed position. The head 20b of the male electrical connector <NUM> is mechanically disengaging the electrical contact fingers <NUM> at a step <NUM>. The mobile body <NUM> is starting to move axially towards the housing <NUM> so as the male electrical connector <NUM> at a step <NUM>. The arc extinguishing gas inside the compression chamber <NUM> is compressed. Arc extinguishing gas starts being expelled from the male connector <NUM> into the cavity 5b through the first channel 51a in the direction of Arrow A towards the female electrical contact <NUM> at a step <NUM>.

With reference to <FIG> and to <FIG>, the switch <NUM> is in a first intermediate opened position. The head 20b of the male electrical connector <NUM> is moving axially inside the nozzle <NUM>. The head 20b is flush with the through holes <NUM> of the nozzle <NUM> at a step <NUM>. Arc extinguishing gas is still expelled from the male connector <NUM> through the first channel 51a in the direction of Arrow A towards the female electrical contact <NUM> at a step <NUM>. Arc extinguishing gas starts being expelled from the male connector <NUM> through the secondary channel <NUM> and then through the through holes <NUM> of the nozzle <NUM> into the cavity 5b in the direction of Arrow B towards the female electrical contact <NUM> at a step <NUM>.

With reference to <FIG>, the switch <NUM> is in a second intermediate opened position. The head 20b of the male electrical connector <NUM> is still moving axially inside the nozzle <NUM> but the head 20b no longer closes the through holes <NUM> of the nozzle <NUM>. Arc extinguishing gas at this stage is still expelled from the male connector <NUM> through the secondary channel <NUM> and then through the through holes <NUM> of the nozzle <NUM> into the cavity 5b in the direction of Arrow B towards the female electrical contact <NUM>.

With reference to <FIG>, the switch <NUM> is in a fully opened position. The male electrical contact <NUM> is electrically disconnected from the female electrical contact <NUM>. There is a gap between the male electrical connector <NUM> and the female electrical connector <NUM> through the cavity 5b. The head 20b of the male electrical conductor <NUM> is inside the nozzle <NUM> and abuts an end of the nozzle. Almost all Arc extinguishing gas has been expelled from the compression chamber <NUM> and electric arcs have been blown out in a step <NUM>.

<FIG> discloses a switch <NUM> including a male electrical connector <NUM> according to a second embodiment of the invention. The male electrical connector <NUM> of the second embodiment is identical with the one of the first embodiment except for the nozzle <NUM>.

The nozzle <NUM> of the male connector <NUM> of the second embodiment has only a first channel 51b. This first channel 51b extends from the male contact arcing rod <NUM> to an external lateral wall <NUM> of the nozzle <NUM>. An arc extinguishing gas flow can be expelled from the male connector <NUM> through the first channel 51b along the direction of arrow D.

The inner surface of the external lateral wall <NUM> is curved and the first channel 51a has a diminishing width d3 towards the central orifice <NUM> of the nozzle <NUM>. Hence, gas flow speed is increased towards the central orifice <NUM> of the nozzle and an electric arc may be blown more efficiently.

<FIG> discloses a switch <NUM> including a male electrical connector <NUM> according to a third embodiment of the invention. The male electrical connector <NUM> of the third embodiment is identical with the one of the second embodiment except for the nozzle <NUM>.

The nozzle <NUM> of the male connector <NUM> of the third embodiment has a first channel 51c having a constant width d4 along the whole axial length of the nozzle <NUM>. An arc extinguishing gas flow can be expelled from the male connector <NUM> through the first channel 51c along the direction of arrow C. The nozzle <NUM> according to the third embodiment is easier to manufacture than the one of the male connector <NUM> of the first embodiment.

<FIG> discloses a switch <NUM> including a male electrical connector <NUM> according to a fourth embodiment of the invention. The male electrical connector <NUM> of the fourth embodiment is identical with the one of the second embodiment except for the nozzle <NUM>.

The nozzle <NUM> of the male connector <NUM> of the fourth embodiment has a tapered first channel 51d. The first channel 51d has a first tapered portion with a diminishing width d5 towards the exit of the male connector <NUM>. A second portion of the first channel 51d nearer the exit of the nozzle <NUM> has a constant width. An arc extinguishing gas flow can be expelled from the male connector <NUM> through the first channel 51d in the direction of arrow E. Gas flow speed is also increased in the tapered section of the first channel 51d.

Thanks to the switch <NUM> according to the invention, an arc between the male arcing rod <NUM> and the female contact <NUM> can be efficiently blown out with a smaller and lighter switch <NUM>. Accordingly, the switch <NUM> including can also be smaller and lighter. It is possible to use an arc extinguishing gas with smaller greenhouse effect in the switch <NUM>, such as alternative gas mixtures to SF<NUM>.

The mobile body <NUM> moves axially at a lower speed than the male electrical contact <NUM>. Hence, the arc extinguishing gas tends to be expelled at a higher speed and at a higher pressure when the male electrical contact <NUM> is sufficiently far away from the female electrical contact <NUM> and when an electric arc can be efficiently blown out.

The first electrical connector <NUM> can be a female electrical connector and the second electrical connector <NUM> is then a male electrical connector.

The electrical connector <NUM> can be used in a disconnector and/or a grounding device.

The male electrical connector <NUM> can be without nozzle <NUM>. In that case, the arc extinguishing gas can be expelled through the mobile body <NUM>.

The actuation mechanism <NUM> may comprise a cam and a cam follower outside of the entrance gear <NUM>.

The actuation mechanism <NUM> can comprise more than two traction rods <NUM>. The traction rods <NUM> can be replaced by a single tube surrounding the male electrical contact <NUM>.

Claim 1:
Electrical switch (<NUM>) for a medium or a high voltage gas insulated electrical equipment (<NUM>) comprising:
a first electrical contact (<NUM>) configured to move axially along a longitudinal direction (X-X) of the first electrical contact (<NUM>) to electrically engage a second electrical contact (<NUM>),
a mobile body (<NUM>) partially delimiting a compression chamber (<NUM>) to be filled with an arc extinguishing fluid,
a fixed body (<NUM>) comprising a wall (<NUM>) of the compression chamber (<NUM>),
wherein the compression chamber (<NUM>) comprises at least an opening through which the arc extinguishing fluid is configured to flow towards an electric arc formed between the first electrical contact (<NUM>) and the second electrical contact (<NUM>) when the first electrical contact (<NUM>) electrically disengages the second electrical contact (<NUM>) to blow out the electrical arc,
wherein the mobile body (<NUM>) and the fixed body (<NUM>) surround the first electrical contact (<NUM>),
characterized in that the electrical switch (<NUM>) comprises an actuation mechanism (<NUM>) configured to move the first electrical contact (<NUM>) and the mobile body (<NUM>) axially with different speeds relative to the fixed body (<NUM>),
wherein the actuation mechanism (<NUM>) comprises a disconnecting lever (<NUM>), at least a linking arm (<NUM>) connecting the disconnecting lever (<NUM>) to the mobile body (<NUM>) by at least a first link (<NUM>), and wherein the first electrical contact (<NUM>) is connected to the disconnecting lever (<NUM>) by at least a second link (<NUM>),
wherein the actuation mechanism (<NUM>) comprises a rudder (<NUM>) through which the first electrical contact (<NUM>) is configured to extend and to move axially,
wherein an end of the linking arm (<NUM>) is fixed to the rudder (<NUM>), and wherein the actuation mechanism (<NUM>) comprises at least a traction rod (<NUM>) extending from the rudder (<NUM>) to the mobile body (<NUM>) to move the mobile body (<NUM>) axially relative to the fixed body (<NUM>),
wherein the actuation mechanism (<NUM>) comprises a slave connecting rod (<NUM>) connecting the first electrical contact (<NUM>) to the disconnecting lever (<NUM>) by at least a link.