| 摘要 |
<p>#CMT# #/CMT# The device has a hydraulic unit with a ring (13) that is provided with calibrated radial orifices (14) and mounted and centered on a cylindrical shoulder (15) projected into a working hydraulic compartment (1) to define an annular fluid-flow space (16) between the ring and the shoulder. The space is in fluid communication with the compartment and one of compression and traction hydraulic peak-limiting valves via the orifices. Recessed end (3a) of a piston (3) surrounds the ring and progressively closes the orifices, during end-of-stroke axial movement of the piston. #CMT# : #/CMT# An independent claim is also included for an aircraft including a main rotor hub for driving blades. #CMT#USE : #/CMT# Device i.e. lead-lag damper, for damping relative movement of two elements of a mechanical system of an aircraft e.g. rotary-wing aircraft (all claimed) i.e. rotorcraft such as helicopter. #CMT#ADVANTAGE : #/CMT# The recessed end of the piston surrounds the ring and progressively closes the orifices during end-of-stroke axial movement of the piston, thus generating progressive damping force to prevent mechanical shock and to attenuate lead-lag movement of the blades to induce unbalance starting up a main rotor of an aircraft, and hence assuring damping of the mechanical system while avoiding generation of end-of-stroke force peak in the device and avoiding damage to the device. The device is totally mechanical, robust and reliable, and complies with aviation standards. The device is simple and compact, so that the device is incorporated onto the main rotor of the aircraft. The configuration of the device allows reducing manufacturing cost of the device, and facilitating easy maintenance of the device. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows an enlarged longitudinal sectional view of a damping device. 1 : Working hydraulic compartment 3 : Piston 3a : Recessed end 13 : Ring 14 : Calibrated radial orifices 15 : Cylindrical shoulder 16 : Annular fluid-flow space.</p> |
