Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Dual piston drag damper for rotary-wing aircraft rotor










Image Number 5 for United States Patent #6676074.

A drag damper for use on a rotary wing aircraft rotor comprises a body defining two variable volume chambers linked by a piston. The chambers are filled with fluid and are connected by a restriction port (35) and by a channel (32) of larger cross-section than the restriction port. A secondary piston slidable and pressure-tight piston is fitted in the channel and loaded by an elastic bias (34). The equivalent mass of this secondary piston (33) and of the fluid which it displaces, and the stiffness of the elastic bias (34) are such that the secondary piston is resonant in the channel (32) at the rotation frequency of the rotor, to filter the dynamic component at this frequency of stresses applied to the damper (20). Furthermore at the natural drag frequency of the corresponding blade, the elastic bias substantially blocks the secondary piston (33) in its channel (32), and the flow of fluid between the chambers (29, 30) of the damper (20) takes place mainly via the restriction port (35) calibrated to provide substantial damping at this frequency.








 
 
  Recently Added Patents
Electric rotating machine for vehicle
Wristwatch
Discharge circuit and method
Lipoprotein analysis by differential charged-particle mobility
Light barrier and method for detecting objects
Multi-touch recognition resistive touch screen for recognizing multi-touch coordinates through capacitor charging time
Masking method and apparatus
  Randomly Featured Patents
Tray for modular construction toys
Tubular induction motor with two directions of rotation for home-automation applications
Memory module
Method of manufacturing electronic device
Non-planar packaging of image sensor
Method of processing duck feet
Nonvolatile semiconductor memory
Process for producing a nanoscale zero-valent metal
Abrasion resistant catalyst
Multicomponent polyacetal-block copolymer-polymer blends