Patent ID: 12208918

DETAILED DESCRIPTION

In reference toFIGS.1to4, the landing gear according to the disclosure, generally referenced100, equips an aircraft1000and comprises a strut1connected at its first end2to the aircraft so as to be able to adopt a deployed position (represented inFIG.1) projecting from the cabin of the aircraft1000and a retracted position in which the strut is comprised in the volume of the cabin of the aircraft1000. The strut1has a second end3which comprises an axle4on which is mounted a pair of wheels5comprising a left wheel5.1and a right wheel5.2. An electric actuator10of which the frame10.1is integral with the strut1extends between the left wheel5.1and the right wheel5.2and is located to the rear of the strut1, relative to the flight direction of the aircraft1000. The axle4also carries a braking device11of the pair of wheels5. A wire harness12connects the actuator10and the braking device11to an electrical system13of the aircraft1000. The aircraft is provided with a ground circuit90to which the strut1made of an electrically conductive material is electrically connected. Thus, the frame10.1of the actuator10is electrically connected to the ground circuit90.

As can be seen inFIG.1, and according to a first embodiment of the disclosure, a first lightning arrester cowl20, lower, extends around a lower quadrant of the actuator10and covers a portion of the wire harness12which extends along the actuator10. The lightning arrester cowl20comprises a metal frame21, in this case, rectangular-shaped, the right longitudinal edge22and the left longitudinal edge23of which respectively comprise three bores22.1,22.2,22.3and three bores23.1,23.2and23.3. The three bores22.1,22.2,22.3and the three bores23.1,23.2and23.3respectively accommodate screws for fixing to the actuator10.

The metal frame21is embedded in an insulating matrix25comprising fibreglass and which constitutes the casing of the first cowl20. The casing of the first cowl20has a vertical section (according to the representations ofFIGS.1and4) substantially triangle-rectangle-shaped. The first cowl20thus comprises a rear face20.1substantially vertical and a lower surface20.2which extends horizontally.

As can be seen inFIG.4, a plurality of conductive pads26, in this case made of copper, are glued onto the matrix25. A first conductive bolt27located in the lower part of the first cowl20when the landing gear100is in its deployed state and in contact with the ground (FIGS.1and5) is connected to a first ground braid28. The first ground braid28is connected by screwing to the strut1. The first bolt27constitutes a first connection point of the first cowl20to the ground circuit90.

A second conductive bolt29located in the upper part of the first cowl20when the landing gear100is in its deployed state (FIGS.1and5) is connected to a second ground braid30. The second ground braid30is connected by screwing to the frame10.1of the actuator10. The second bolt29constitutes a second connection point of the first cowl20to the ground circuit90.

In operation, when the aircraft1000is located on the path of a lightning flash (in flight or on the ground), the lightning flash leaves from the ground and thus strikes a low point of the aircraft1000. The first cowl20being the lowest conductive point of the aircraft1000, the impact point of the lightning flash is located on the lower surface20.2of the first cowl20. The installation of the first braid28makes it possible to minimise the length of the pathway of the lightning flash on the first cowl20until it is directed towards the ground circuit90of the aircraft1000. During the movement of the aircraft1000frontwards, the impact point of the lightning flash travels along the lower surface20.2of the first cowl20, from front to back and then moves onto the rear face20.1of the first cowl20. The installation of the second braid30makes it possible to minimise the length of the pathway of the lightning flash on the first cowl20until it is directed towards the ground circuit90of the aircraft1000.

Thus, a device is obtained, ensuring protection of the wire harness12against lightning. The device of the disclosure also very effectively protects in an opposite way (lightning starting from the sky) from lightning.

The elements which are identical or similar to those described above will have a numerical reference identical to the latter in the following description of the two other embodiments of the disclosure.

According to a second embodiment represented inFIG.6, a second lightning arrester cowl40, upper, is articulated on the first lower cowl20using a pivot41integral with the second cowl40and slidingly mounted in a pair of grooves31integral with the first cowl20. An upper part42of the second cowl40is connected by a connecting rod43articulated on the actuator10.

A third ground braid32extends between the first cowl20and the second cowl40. A fourth ground braid44also extends between the upper cowl40and the actuator10.

It is thus understood that the first cowl20constitutes a lower lightning arrester cowl portion and the second cowl40constitutes an upper lightning arrester cowl.

According to a third embodiment of the disclosure represented inFIG.7, the insulating matrix25comprise carbon and/or epoxy resin, in addition to or in substitution for the fibreglass of the preceding embodiments. Such a material can be made by a stack of layers50of fabric which will be impregnated with resin.

As can be seen inFIG.7, the conductive pads26have been replaced by a metal mesh60which comprises, in this case, bronze. A paint layer70can optionally cover the metal mesh60. This option also applies to embodiments comprising metal terminals.

Naturally, the disclosure is not limited to the described embodiments but covers any variant coming within the scope of the disclosure as defined by the claims.

In particular:although in this case, the cowl comprises a metal frame, the disclosure also applies to other means for electrically connecting the electrical conductor to a ground conductor of the aircraft, like for example a metal mesh, a conductive bar or any other conductive element;although in this case, the cowl comprises conductive bolts, the disclosure also applies to other means for electrically connecting the electrical conductor of the cowl to a ground conductor of the aircraft, like for example a screw, a connection lug sealed in the cowl or welded onto the metal frame;although in this case, the ground braids are connected to the ground circuit of the aircraft by conductive bolts, the disclosure also applies to other types of mechanical connection of the ground braids to the lightning arrester cowl, like for example a gluing, a screwing, a riveting, a welding, a soldering or a resin application;although in this case, the electrical connections between the electrical conductor and the ground conductor comprise one single first ground braid, second ground braid or third ground braid, the disclosure also applies to electrical connections made in the form of several redundant elements, like for example a duplicate third ground braid.