Patent ID: 7407134
Filing Date: 2008-08-05
Classification: B64C

Abstract:
1. A steerable auxiliary nose undercarriage for a rotary wing aircraft, the undercarriage being retractable substantially rearwards and comprising at least: a wheel set having a wheel axle about which at least one wheel rotates; a generally longitudinally-extending oscillating system having a first end adjacent to the wheel axle, and a hinged front end that is longitudinally opposite from said first end, the oscillating system being pivotally mounted via at least one transverse hinge for anchoring to a force-transmission structure for being rigidly secured to the aircraft, and the wheel axle being arranged on the oscillating system via a steering pivot; and a shock-absorbing actuator having a connection end hinged to the oscillating system between the hinged front end and the first end, the shock-absorbing actuator having a coupling end axially opposite from the connection end, the coupling end being hinged to the structure, the oscillating system being vertically swingable about the hinged front end over a distance that is greater than a shock-absorbing stroke; wherein: said steering pivot comprises a steering axis substantially intersecting the wheel axle, said steering pivot enabling the wheel to be steered on either side of a position corresponding to the aircraft running in a straight line by means of a steering actuator connected to a portion of the steering pivot that is constrained to pivot with the wheel axle, said steering pivot and said steering actuator both being substantially integrated around the steering axis, so that said steering axis extends through both said steering pivot and said steering actuator; and the shock-absorbing actuator possesses means for retracting the oscillating system beyond an abutment position marking the end of the shock-absorbing stroke, so that the oscillating system and the shock-absorbing actuator perform both a function of absorbing shocks and a function of retracting the undercarriage.