Stepped Planetary Gear Oil Supply Cups for Multi-Stage Lubrication

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current gear oil supply devices for turbomachines, particularly those with planetary or differential gear reducers, face challenges in modulating oil flow distribution based on turbomachine speed and differentiating lubricant types, leading to inefficiencies and maintenance issues due to the use of complex and unreliable systems with significant pressure drops.

Innovation Solution

A stepped oil supply device with two annular cups, each connected to independent oil injection means, allowing for angular and centripetal oil distribution, enabling separate lubrication stages with different lubricant properties adapted to specific gear needs, and facilitating easier mounting and assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a single cup oil supply device is used, then the structure is simple, but it cannot differentiate lubricant types for different gear stages

Engineering Contradiction:
ImproveDifferentiation of lubricant typesVSAvoidStructure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The oil supply device is divided into multiple cups (first cup and second cup) that are axially offset and segmented along the axis of rotation. Each cup is dedicated to a specific gear stage (solar pinion/satellites vs. satellite bearings), allowing different lubricant types to be supplied to different stages. This segmentation enables lubricant differentiation while maintaining a relatively simple overall structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each cup is equipped with nozzles of different diameters tailored to the specific lubrication needs of each gear stage. The first cup supplies oil to the solar pinion and satellites, while the second cup supplies oil to the satellite bearings. This local quality approach allows each region to receive appropriately customized lubrication.

Inventive Principle:
Principle #3Local quality

2Reliability

If rotary joint systems are used to transfer oil, then oil can be supplied to rotating planetary gears, but the system becomes bulky and prone to wear

Engineering Contradiction:
ImproveSystem reliabilityVSAvoidSystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The oil supply device is directly mounted on the planet carrier and rotates together with the planetary gears. The cups are integral to the rotating assembly, eliminating the need for separate rotary joints or seals. This self-service approach allows the system to supply oil to rotating gears without requiring complex intermediary mechanisms, thereby improving reliability and reducing complexity.

Inventive Principle:
Principle #25Self-service

3Adaptability or versatility

If nozzles of the same diameter are used for each axial section, then the structure is simple, but it cannot adjust oil flow distribution based on lubrication requirements

Engineering Contradiction:
ImproveOil flow adjustment capabilityVSAvoidManufacturing simplicity
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The nozzles in each cup have different diameters according to the specific lubrication requirements of each gear stage. The first cup has nozzles sized for the solar pinion and satellite gear lubrication, while the second cup has nozzles sized for satellite bearing lubrication. This local quality approach allows optimized oil flow distribution while maintaining manufacturing feasibility through standardized nozzle components.

Inventive Principle:
Principle #3Local quality

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 solution provides a reliable, efficient, and adaptable lubrication system that overcomes pressure drop issues and allows for differentiated lubricant use, enhancing the maintenance and operational efficiency of turbomachine reducers.

Implementation Method 1

The cup, which rotates with the oil supply device (referred to as a 'wheel' or 'distributor') around the injection means, confines the oil recovered by centrifugation before directing it to the gear lubrication means

Methodology Applied
Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentEP3822516B1Stage impeller for supplying oil to an epicyclic or planetary reduction gear
Publication Date: 2023.02.15 SAFRAN TRANSMISSION SYST
  • EP3822516B1 patent drawingFigure 1~2
  • EP3822516B1 patent drawingFigure 3
  • EP3822516B1 patent drawingFigure 4

AI summary

The invention relates to an oil supply device (54) for supplying oil to an epicyclic gear reducer (32), the oil coming from at least one oil injection means (58a, 58b) fixed relative to the reducer (32), said oil supply device (54) comprising at least one cup (56a, 56b) integral with a planet carrier (44) of the reducer and substantially annular, open radially with respect to an axis (X) of the reducer (32), and whose walls (62a, 64a, 66a, 62b, 64b, 66c) delimit a cavity (59a, 59b) supplied by said at least one oil injection means and which supplies at least one of the oil distribution circuits (54a, 54b) of the reducer, the oil supply device (54) being staged and comprising at least two independent stages equipped with coaxial cups (56a, 56b) of different diameters, each supplying an associated oil circuit (54a, 54b) and configured to receive the oil axially, in a centripetal manner,or tangentially, or along an inclined direction combining two of said directions.