Planet Carrier Lubricant Path Layout for Higher Wind Gearbox Loads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional gearbox lubrication systems for wind turbines face high stress concentrations at the upwind plug region of the second-stage planetary carrier, limiting load capacity and hindering upgrades for increased load needs.
Innovation Solution
The lubricant path is redefined through a manufactured component, such as a casting or pipe assembly, positioned between the second and first planetary carriers, avoiding the pin shafts and eliminating the need for holes in the load path, thereby reducing stress concentrations and improving machinability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional lubrication path design is used through the second-stage planetary carrier, then lubricant can reach the gear meshes, but high stress concentrations occur at the upwind plug region limiting load capacity
Solution Approach 1:
A lubricant transfer device is introduced as an intermediary component between the stationary gearbox housing and the rotating planetary carrier. This device includes a lubricant transfer path that extends along the rotating direction, allowing lubricant to be transported from the housing to the carrier without passing through high-stress regions, thus maintaining both lubrication effectiveness and structural strength
Solution Approach 2:
The lubrication path is reconfigured from a conventional radial or axial path through the carrier body to a tangential path that follows the rotating direction along the outer periphery. This dimensional change in path orientation allows lubricant delivery while avoiding stress concentration zones at the upwind plug region
2Reliability
If holes are drilled in the planetary carrier for lubricant delivery, then lubricant reaches the gears, but stress concentrations increase and machinability is reduced
Solution Approach 1:
The lubricant transfer device serves as a mediator that eliminates the need to drill holes directly through the planetary carrier. The device includes a lubricant transfer path that can be implemented as a separate component or surface feature, providing lubricant delivery without compromising the carrier's structural integrity or machinability
Solution Approach 2:
The lubrication system is segmented into distinct components: a stationary lubricant supply in the gearbox housing and a rotating lubricant transfer device on the planetary carrier. This segmentation allows the carrier to maintain its structural strength while the transfer device handles lubricant delivery, avoiding the need for complex hole drilling and plug installation in the carrier
3Reliability
If traditional lubrication paths are used, then lubricant can be supplied to gears, but bottle-necking occurs limiting further load upgrades
Solution Approach 1:
The lubrication system is designed to be dynamic and adaptable to varying load conditions. The lubricant transfer path extends along the rotating direction, allowing the system to efficiently deliver lubricant across different operating speeds and load levels, removing the bottle-neck that limited previous upgrades
Solution Approach 2:
The lubricant transfer device is designed with universal applicability across different gearbox configurations and load requirements. The tangential path design along the outer periphery provides a flexible platform that can accommodate various planet carrier sizes and gear arrangements, enabling future load upgrades without redesigning the fundamental lubrication approach
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design enhances the static strength and fatigue life of the planetary carrier, allowing for increased load capacity and simplified machinability while reducing lubricant bottle-necking, thus supporting further upgrades and operational efficiency.
Implementation Method 1
Lubrication systems are often used within the gearbox to circulate oil therethrough, thereby decreasing the friction between the components of the gearbox
Implementation Method 2
Lubrication systems are often used within the gearbox to circulate oil therethrough, thereby decreasing the friction between the components of the gearbox as well as providing cooling for such components
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A gearbox assembly includes a gearbox housing (137) and a planetary gear system (138) configured within the gearbox housing. The planetary gear system includes a plurality of planet gears (144), at least one sun gear (146), at least one ring gear (141), at least one planetary carrier (142) operatively coupled with the plurality of planet gears, and a plurality of pin shafts (143, 145). Each of the plurality of planet gears are arranged so as to rotate around one of the plurality of pin shafts. Further, the plurality of planet gears are engaged with the ring gear and configured to rotate about the sun gear. The gearbox assembly also includes a first lubricant path (150) defined from a first location to a second location through the at least one planetary carrier. Moreover, the first lubricant path is located outside of the plurality of pin shafts.