Planet carrier arrangements
A planet carrier 100 has a member 110 which is resistant to buckling caused by torsional stress and which increases a torsional stiffness of the planet carrier 100 , so that a torsion load is transmitted evenly from the input member 120 into the planet pins 104 without twisting the planet carrier 100.
1. A planet carrier adapted to transmit a torsion load from an input member into a plurality of planet pins, said planet carrier comprising:
a first and second carrier plate;
a plurality of carrier legs disposed between said first and second carrier plates;
and a member connected to said carrier legs and one of said carrier plates;
wherein said member is resistant to buckling caused by torsional stress and increases a torsional stiffness of said planet carrier, whereby a torsion load is transmitted evenly from said input member into said planet pins without twisting said planet carrier, wherein said member extends axially away from said carrier, wherein said member is frustoconical in shape, and wherein said member is located around a periphery of said planet carrier.
2. The planet carrier according to claim 1 , wherein said member comprises a flange, rib or rim.
3. The planet carrier according to claim 2 , wherein said member extends from said carrier legs to form a single kinematic structure comprising said legs and said member.
4. The planet carrier according to claim 3 , wherein said carrier plates are connected to said assembly comprising said member and said legs.
5. The planet carrier according to claim 4 , additionally comprising a plurality of planet pins, wherein said planet pins are connected to said assembly comprising said member and said legs via said carrier plates, wherein torsion load is transmitted to said planet pins without twisting said carrier plate.
6. The planet carrier according to claim 4 , wherein said member extends from said carrier plate to form a single kinematic structure comprising said member and said carrier plate.
7. The planet carrier according to claim 6 , wherein said assembly comprising said member and said carrier plate is connected to said carrier legs and twisting of said legs relative to said carrier plate is resisted.
8. The planet carrier according to claim 7 , wherein said carrier legs comprise columns located between two carrier plates.
9. The planet carrier according to claim 1 , wherein said member is connected to said input member.
10. The planet carrier according to claim 1 , additionally comprising a further member connected to said carrier legs and one of said carrier plates, wherein said member is located at one end of said planet carrier and said further member is located at an other end of said planet carrier.
11. A gearbox comprising said planet carrier of claim 1 .
12. A wind turbine comprising said gearbox according to claim 11 .