Rotor head for helicopter - includes bidirectional joint centre of which takes weight instead of needle-roller bearings

摘要

The helicopter rotor head includes four blades propelled by jets of pressurised cold air passing through an integral distributor. The head contains a cross (CR) the arms (CRa-CRd) of which run in needle-roller bearings. One pair of opposing arms (CRa,CRb) is connected into the distributor and the other into an upper shell. The centre of the cross has upper (CRe) and lower (CRf) spherical parts which contact concave supports (CMa,CMb) one attached to the upper shell (E2) and the other to the distributor (E1). The supports (CMa,CMb) take the weight of the upper shell instead of the needle-roller bearings, ensuring greater longevity.