Face Coupling Root Transitions for Gas Turbine Torque

Solution Overview

Problem

Existing face couplings in gas turbine engines face challenges in managing peak stresses and ensuring reliable torque transmission due to edge effects and contact between teeth, leading to potential dislodgment and reduced service life.

Innovation Solution

The implementation of a face coupling design featuring root transitions in the form of root recesses and fillet radii on both driving and driven teeth, which prevent tip edges from contacting adjacent flanks, thereby reducing peak stresses and ensuring consistent engagement and torque transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If traditional face coupling teeth design is used, then torque transmission is achieved, but peak stresses occur at tooth tip edges and service life is reduced

Engineering Contradiction:

Improvetooth root strengthVSAvoidcoupling service life

Core Design Contradiction:

StrengthVSDuration of action of stationary object

Solution Approach 1:

The patent applies local quality by implementing different geometric features at different locations of the tooth structure. Root recesses are provided at the tooth roots while fillet radii are provided at the tooth tip edges. This localized modification optimizes stress distribution at each critical location, reducing peak stresses and extending coupling service life while maintaining torque transmission capability.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs curvature by introducing fillet radii at the tooth tip edges and root recesses at the tooth roots. These curved transitions eliminate sharp corners and stress concentration points, creating smooth stress flow paths that reduce peak stresses and prevent premature failure, thereby extending the coupling's operational life.

Inventive Principle:

Principle #14Spheroidality (Curvature)

2Power

If tight engagement between teeth is maintained for reliable torque transmission, then torque capacity is improved, but peak stresses increase due to edge effects

Engineering Contradiction:

Improvetorque transmission capacityVSAvoidpeak stress at tooth edges

Core Design Contradiction:

PowerVSStress or pressure

Solution Approach 1:

The patent applies local quality by implementing different geometric features at different locations of the tooth structure. Root recesses are provided at the tooth roots while fillet radii are provided at the tooth tip edges. This localized modification optimizes stress distribution at each critical location, reducing peak stresses and extending coupling service life while maintaining torque transmission capability.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs curvature by introducing fillet radii at the tooth tip edges and root recesses at the tooth roots. These curved transitions eliminate sharp corners and stress concentration points, creating smooth stress flow paths that reduce peak stresses and prevent premature failure, thereby extending the coupling's operational life.

Inventive Principle:

Principle #14Spheroidality (Curvature)

Data Source

PatentEP2519755B1Face coupling

Publication Date: 2018.07.04 ROLLS ROYCE CORP

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AI summary

One embodiment of the present invention is a gas turbine engine. Another embodiment is a face coupling. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for face couplings. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.