Wind Turbine Planetary Gear Carrier Web for Tight Assembly Clearance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing planetary gears face challenges in achieving high power density while minimizing space requirements, particularly in wind turbines, due to the need for a low gear ratio and large carrier cheek diameters that can ensure proper assembly and operation without hitting internal toothing.
Innovation Solution
A multi-planetary gear design with a planet carrier web positioned between the carrier cheeks and the ring gear, allowing for a small radial distance between the carrier cheeks and the ring gear's internal toothing, while maintaining sufficient clearance to prevent abutment, and featuring a planet carrier web that extends radially outward to support the carrier cheeks and improve lubrication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the outer diameter of support webs is increased to enable assembly by moving radially past internal toothing, then assembly is enabled, but the radial clearance to ring gear internal toothing is reduced increasing risk of contact
Solution Approach 1:
A planet carrier web is introduced as an intermediary component between the support webs and the ring gear. This web extends radially outward beyond the support webs and positions itself in the space between the planet gears and ring gear, preventing direct contact between the support webs and ring gear internal toothing while enabling the support webs to maintain their larger outer diameter for assembly purposes
Solution Approach 2:
The planet carrier web utilizes the axial dimension to create radial clearance. By positioning the web in the axial space between the planet gears and ring gear, it effectively reduces the radial distance between support webs and ring gear internal toothing, preventing contact while maintaining assembly capability
2Power
If multiple planet gears are used to increase power density, then power density increases, but the radial space available for carrier webs is reduced
Solution Approach 1:
The planet carrier web extends in the axial dimension rather than requiring additional radial space. By utilizing the axial gap between planet gears and ring gear, the design accommodates multiple planet gears for high power density while the web maintains sufficient length to perform its positioning and lubrication functions
Solution Approach 2:
The planet carrier web is nested in the space between the planet gears and ring gear, utilizing the existing radial and axial clearance. This allows the web to extend radially outward beyond support webs without increasing the overall radial dimensions of the planetary gear set
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a planetary gearbox (26) comprising: a planet carrier (44) having a first support flange (40) and a second support flange (42); planet gears (30) rotatably mounted on the first support flange (40) and the second support flange (42) in each case via a bearing pin (38); a ring gear (36) that meshes with the planet gears (30), wherein an assembly clearance is formed between a flange outer diameter (D) of the first support flange (40) and the second support flange (42) on the one hand and an inner diameter of the ring gear (36) on the other hand; and at least one planet carrier arm (68) that positions the first support flange (40) and the second support flange (42) at a defined distance from one another, wherein a radially-outward facing outer side (74) of the planet carrier arm (68) is spaced more radially inwards from a radially inner tip radius of an inner toothing (34) of the ring gear (36) than the first support flange (40) and the second support flange (42) and is arranged radially outside an inner diameter of the planet gears (30). This makes it possible to obtain a planetary gearbox (26) having a high power density while requiring little installation space.