대표
청구항
▼
The invention claimed is: 1. An aircraft, comprising an aircraft landing gear, the aircraft landing gear comprising: an arm, an actuator arranged to rotate the arm, a stop for limiting rotary movement of the arm during takeoff and landing of the aircraft, a leg on which the arm is rotatably mounted, and a bogie at a lower end of the leg, the bogie being moveable in a direction along a length of the leg and pivotable between a trimmed deployed position and a stowable position, wherein movement of the bogie between the trimmed deployed position and the st...
The invention claimed is: 1. An aircraft, comprising an aircraft landing gear, the aircraft landing gear comprising: an arm, an actuator arranged to rotate the arm, a stop for limiting rotary movement of the arm during takeoff and landing of the aircraft, a leg on which the arm is rotatably mounted, and a bogie at a lower end of the leg, the bogie being moveable in a direction along a length of the leg and pivotable between a trimmed deployed position and a stowable position, wherein movement of the bogie between the trimmed deployed position and the stowable position is associated with rotary movement of the arm, by the actuator, between (i) a first position in which the bogie is positioned in the trimmed deployed position and (ii) a second position in which the bogie is positioned in the stowable position and in which the arm is completely separate from the stop, the landing gear being arranged such that the actuator is able to cause movement of the bogie from the trimmed deployed position to the stowable position, without requiring the actuator to sustain large forces generated on take off and landing of the aircraft; wherein the arm is connected to the bogie via a link; and the link has an extendible length that is fully extended when the bogie is in the trimmed deployed position and the arm is in the first position. 2. An aircraft according to claim 1, wherein movement of the arm between the first position and the second position effects movement of the bogie between the trimmed deployed position and the stowable position. 3. An aircraft according to claim 1, wherein the aircraft landing gear is so arranged that when the arm is in the first position, the arm is in contact with the stop. 4. An aircraft according to claim 1, wherein the aircraft landing gear is so arranged that during at least one of (i) take-off and (ii) landing of the aircraft, the arm is in the first position and is subjected to a moment in a direction opposite to that required to move the arm from the first to the second position. 5. An aircraft according to claim 1, wherein the landing gear is configured in a semi-levered arrangement. 6. An aircraft according to claim 1, wherein the landing gear is arranged such that the actuator is subjected to less than 10% of the maximum load sustained by the landing gear on take-off and/or landing of the aircraft. 7. A method of aligning the bogie on the aircraft of claim 1, the method comprising: causing the actuator to rotate the arm from the first position to the second position. 8. An aircraft according to claim 1, the landing gear further comprising (i) a first pivot at which the link is pivotably connected to the arm, and (ii) a second pivot at which the link is pivotably connected to the bogie, wherein, when the bogie is in the trimmed deployed position and the arm is in the first position, the first and second pivots and the location at which the arm is rotatably mounted on the leg are substantially in line. 9. An aircraft according to claim 8, wherein, when the bogie is in the trimmed deployed position and the arm is in the first position, the location at which the arm is rotatably mounted on the leg is positioned, as seen in a longitudinal direction of said link, between the first and second pivots. 10. An aircraft according to claim 1, further comprising: a position sensor arranged to output a signal in dependence on the position of the arm relative to the leg. 11. An aircraft according to claim 10, further comprising: a control unit arranged to control the actuator to rotate the arm in response to the output signal from the position sensor. 12. An aircraft, comprising an aircraft landing gear, the aircraft landing gear comprising: an arm, an actuator arranged to rotate the arm, a stop for limiting rotary movement of the arm during takeoff and landing of the aircraft, a leg on which the arm is rotatably mounted, and a bogie at a lower end of the leg, the bogie being moveable in a direction along a length of the leg and pivotable between a trimmed deployed position and a stowable position, wherein movement of the bogie between the trimmed deployed position and the stowable position is associated with rotary movement of the arm, by the actuator, between (i) a first position in which the bogie is positioned in the trimmed deployed position and (ii) a second position in which the bogie is positioned in the stowable position and in which the arm is completely separate from the stop, the landing gear being arranged such that the actuator is able to cause movement of the bogie from the trimmed deployed position to the stowable position, without requiring the actuator to sustain large forces generated on take off and landing of the aircraft; wherein the arm is connected to the bogie via a link; and the landing gear is arranged such that, during takeoff and landing of the aircraft and in the deployed position, the net force to which the link is subjected, has a component along the length of the link that is considerably greater than the component of force normal to the length of the link, and the net force to which the arm is subjected has a component along the length of the arm that is considerably greater than the component of force normal to the length of the arm. 13. An aircraft landing gear, comprising: an arm; an actuator arranged to rotate the arm; a stop for limiting rotary movement of the arm during takeoff and landing of the aircraft; a leg on which the arm is rotatably mounted; and a bogie at a lower end of the leg, the bogie being moveable in a direction along a length of the leg and pivotable between a trimmed deployed position and a stowable position; wherein movement of the bogie between the trimmed deployed position and the stowable position is associated with rotary movement of the arm, by the actuator, between (i) a first position in which the bogie is positioned in the trimmed deployed position and (ii) a second position in which the bogie is positioned in the stowable position and in which the arm is completely separate from the stop; the landing gear being arranged such that the actuator is able to cause movement of the bogie from the trimmed deployed position to the stowable position, without requiring the actuator to sustain large forces generated on take off and landing of the aircraft; wherein the arm is connected to the bogie via a link; and the link has an extendible length that is fully extended when the bogie is in the trimmed deployed position and the arm is in the first position. 14. In an aircraft, the improvement comprising an aircraft landing gear, the aircraft landing gear comprising: an arm, an actuator arranged to rotate the arm, a stop for limiting rotary movement of the arm during takeoff and landing of the aircraft, a leg on which the arm is rotatably mounted, and a bogie at a lower end of the leg, the bogie being moveable in a direction along a length of the leg and pivotable between a trimmed deployed position and a stowable position, wherein movement of the bogie between the trimmed deployed position and the stowable position is associated with rotary movement of the arm, by the actuator, between (i) a first position in which the bogie is positioned in the trimmed deployed position and (ii) a second position in which the bogie is positioned in the stowable position and in which the arm is completely separate from the stop, the landing gear being arranged such that the actuator is able to cause movement of the bogie from the trimmed deployed position to the stowable position, without requiring the actuator to sustain large forces generated on take off and landing of the aircraft; wherein the arm is connected to the bogie via a link; and when the bogie is in the trimmed deployed position and the arm is in the first position, a tensile force, which occurs along the longitudinal direction of the link during take-off and landing of the aircraft, generates a compressive force in the arm while pulling the arm toward and against the stop in a direction opposite to that required to move the arm from the first to the second position. 15. An aircraft, comprising an aircraft landing gear, the aircraft landing gear comprising: a leg, a stop on the leg, an arm rotatably mounted on the leg, said arm being rotatable between a first position, where the arm rests on the stop, and a second position where the arm is completely separate from the stop, a bogie at a lower end of the leg, the bogie being moveable along a longitudinal direction of the leg and pivotable between a trimmed deployed position and a stowable position, and a link comprising, along a longitudinal direction thereof, first and second pivots at which the link is pivotably connected to the arm and the bogie, respectively, to effect movement of the bogie between the trimmed deployed position and the stowable position by rotary movement of the arm between the first position, in which the bogie is positioned in the trimmed deployed position, and the second position, in which the bogie is positioned in the stowable position, wherein, when the bogie is in the trimmed deployed position and the arm is in the first position, the location at which the arm is rotatably mounted on the leg is positioned, as seen in the longitudinal direction of said link, between the first and second pivots. 16. An aircraft according to claim 15, further comprising: an actuator arranged to rotate the arm, and a control unit arranged to controllably cause the actuator to rotate the arm from the first position to the second position, thereby moving the bogie from the trimmed deployed position into the stowable position after take-off of the aircraft. 17. An aircraft according to claim 15, wherein, when the bogie is in the trimmed deployed position and the arm is in the first position, a tensile force, which occurs along the longitudinal direction of the link during take-off and landing of the aircraft, generates a compressive force in the arm while pulling the arm toward and against the stop in a direction opposite to that required to move the arm from the first to the second position. 18. An aircraft according to claim 17, wherein the link has, between said first and second pivots, an extendible length that is fully extended when the bogie is in the trimmed deployed position and the arm is in the first position.