US 12,258,943 B2
Lubrication system for a pitch bearing of a wind turbine
Jitendra Kumar Sahu, Bangalore (IN); and Gerard Iain Madden, Leighton Buzzard (GB)
Assigned to General Electric Renovables Espana, S.L., Barcelona (ES)
Filed by General Electric Renovables Espana, S.L., Barcelona (ES)
Filed on Jan. 12, 2023, as Appl. No. 18/096,096.
Claims priority of application No. 202211002266 (IN), filed on Jan. 14, 2022.
Prior Publication US 2023/0228254 A1, Jul. 20, 2023
Int. Cl. F16C 33/66 (2006.01); F03D 80/70 (2016.01); F16C 33/72 (2006.01)
CPC F03D 80/70 (2016.05) [F16C 33/66 (2013.01); F16C 33/72 (2013.01); F05B 2260/98 (2013.01); F16C 2360/31 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A lubrication system for a slewing ring bearing of a wind turbine, the lubrication system comprising:
the slewing ring bearing comprising an outer race, an inner race arranged concentrically within the outer race, and a plurality of rolling elements positioned between the outer and inner races, the inner race rotatable with respect to the outer race;
a lubricant for lubricating contact surfaces between the outer race, the inner race, and the plurality of rolling elements;
at least one lubricant inlet formed into a first side of the inner race of the slewing ring bearing;
at least one inlet seal for sealing the at least one lubricant inlet so as to prevent the lubricant from leaking from the at least one lubricant inlet;
at least one lubricant outlet formed into an opposing, second side of the inner race of the slewing ring bearing; and
at least one lubricant collection container arranged adjacent to and in fluid communication with the at least one lubricant outlet, the at least one lubricant collection container being mounted to the inner race of the slewing ring bearing,
wherein, during operation of the wind turbine, at least one of a slope of the slewing ring bearing, gravity, and a centrifugal effect cause the lubricant to flow throughout the slewing ring bearing to lubricate the contact surfaces between the outer race, the inner race, and the plurality of rolling elements without exiting a closed volume defined by the at least one inlet seal and the at least one lubricant collection container,
wherein the at least one lubricant outlet defines an overall length having a first end and a second end, wherein the overall length is straight from the first end to the second end to prevent back flow from the at least one lubricant collection container back into the inner race.
 
15. A wind turbine, comprising:
a tower;
a nacelle mounted on the tower;
a rotor mounted to the nacelle and comprising a rotatable hub with at least one rotor blade mounted thereto;
a pitch bearing secured between the rotatable hub and the at least one rotor blade for facilitating rotation of the at least one rotor blade about a pitch axis, the pitch bearing comprising an outer race, an inner race arranged concentrically within the outer race, and a plurality of rolling elements positioned between the outer and inner races, the inner race rotatable with respect to the outer race; and
a lubrication system comprising:
a lubricant for lubricating contact surfaces between the outer race, the inner race, and the plurality of rolling elements;
at least one lubricant inlet formed into a first side of the inner race of the pitch bearing;
at least one inlet seal for sealing the at least one lubricant inlet so as to prevent the lubricant from leaking from the at least one lubricant inlet;
at least one lubricant outlet formed into an opposing, second side of the inner race of the pitch bearing; and
at least one lubricant collection container arranged adjacent to and in fluid communication with the at least one lubricant outlet, the at least one lubricant collection container being mounted to the inner race of the pitch bearing,
wherein, during operation of the wind turbine, at least one of a slope of the pitch bearing, gravity, and a centrifugal effect cause the lubricant to flow throughout the pitch bearing to lubricate the contact surfaces between the outer race, the inner race, and the plurality of rolling elements without exiting a closed volume defined by the at least one inlet seal and the at least one lubricant collection container,
wherein the at least one lubricant outlet defines an overall length having a first end and a second end, wherein the overall length is straight from the first end to the second end to prevent back flow from the at least one lubricant collection container back into the inner race.