Abstract: A wind turbine gear box arrangement having one or more bearings located in a single region along the longitudinal axis and arranged to provide support between an input shaft and a non-rotating support component. The one or more bearings are arranged to at least partially restrict non-rotational movement between the input shaft and the non-rotating support component. A portion along the longitudinal axis between said input shaft and the non-rotating support component is bearingless outside the single region.

Abstract: A gearbox for a wind turbine has a bearing arrangement positioned on the downwind side of a first stage planet carrier at a single locus. The planet carrier has a portion extending radially inwards and axially downwind from the planet gears. Thus, the weight of the gearbox is supported between the two theoretical support points of the pair of back to back tapered roller bearings at the downwind side of the first stage planet carrier. A member of unitary construction comprising gearbox flange, input shaft and first stage planet carrier, which can be cast as one piece, reduces the weight of this part compared to previous designs having separate components.

Abstract: 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.

Abstract: A gear arrangement including a first gear arranged to rotate about a first longitudinal axis and including a first plurality of gear teeth, and a first portion including a first surface and a second gear arranged to rotate about a second longitudinal axis and including a second plurality of gear teeth, and a second portion including a second surface. The first surface and the second surface are arranged to abut one another and restrict relative non-rotational movement of the first gear and the second gear.

Abstract: A gearbox for a wind turbine has a bearing arrangement positioned on the downwind side of a first stage planet carrier at a single locus. The planet carrier has a portion extending radially inwards and axially downwind from the planet gears. Thus, the weight of the gearbox is supported between the two theoretical support points of the pair of back to back tapered roller bearings at the down wind side of the first stage planet carrier. A member of unitary construction comprising gearbox flange, input shaft and first stage planet carrier, which can be cast as one piece, reduces the weight of this part compared to previous designs having separate components.