Elastic Balancing Clip for Gas Turbine Rotor

Solution Overview

Problem

Existing methods for balancing rotor assemblies in gas turbine engines require additional securing devices like rivets, increasing complexity and weight, which is undesirable.

Innovation Solution

A balancing weight clip with a weight portion and elastically deformable flange engaging portions that securely attach to a rotor disc's flange using a detent and groove mechanism, eliminating the need for additional fasteners.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If additional securing devices like rivets are used to attach balancing weights to the rotor, then the balancing weight is securely fixed, but the total weight and assembly complexity increase

Engineering Contradiction:

Improvesecuring reliabilityVSAvoidtotal assembly weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent merges the securing function and the weight function into a single integrated balancing weight clip. The clip's engagement portions directly attach to the rotor flange without requiring separate fasteners, eliminating additional weight while maintaining secure fixation through the elastic deformation and detent mechanism.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The balancing weight clip is self-securing through its elastic deformation capability. The engagement portions elastically deform to snap into place on the rotor flange and lock via the detent mechanism, eliminating the need for external securing devices like rivets or bolts.

Inventive Principle:

Principle #25Self-service

2Reliability

If additional securing devices like rivets are used to attach balancing weights to the rotor, then the balancing weight is securely fixed, but the assembly complexity increases

Engineering Contradiction:

Improvesecuring reliabilityVSAvoidassembly complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the securing function and the weight function into a single integrated balancing weight clip. The clip's engagement portions directly attach to the rotor flange without requiring separate fasteners, eliminating additional weight while maintaining secure fixation through the elastic deformation and detent mechanism.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The balancing weight clip is self-securing through its elastic deformation capability. The engagement portions elastically deform to snap into place on the rotor flange and lock via the detent mechanism, eliminating the need for external securing devices like rivets or bolts.

Inventive Principle:

Principle #25Self-service

3Device complexity

If the flange engaging portions are rigid, then the structure is simple, but the installation and removal process becomes difficult

Engineering Contradiction:

Improvestructural simplicityVSAvoidinstallation ease

Core Design Contradiction:

Device complexityVSEase of operation

Solution Approach 1:

The patent introduces dynamic elasticity to the previously static rigid structure. The engagement portions are designed to elastically deform during installation and removal, allowing the clip to flex into place and release easily, while maintaining structural simplicity in the overall design.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the mechanical parameter of the engagement portions from rigid to elastically deformable. This allows the material to temporarily change shape during installation/removal operations, improving ease of operation while returning to its original simple structural form during normal operation.

Inventive Principle:

Principle #35Parameter changes

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

The solution provides effective weight balancing without increasing the rotor assembly's weight or complexity, ensuring stability and ease of installation/removal, thereby simplifying the balancing process.

Implementation Method 1

at least one of the first and second flange engaging portions being elastically deformable so that the first and second flange engaging portions are elastically moveable away from one another to receive the flange in the flange receiving opening

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Implementation Method 2

the first flange engaging portion being provided with a detent facing the second flange engaging portion and mating with the circumferential groove

Methodology Applied

Scientific EffectMechanical interlocking: Mechanical Fastener

Data Source

PatentUS8353670B2Axial balancing clip weight for rotor assembly and method for balancing a rotor assembly

Publication Date: 2013.01.15 PRATT & WHITNEY CANADA CORP

AI summary

A balancing weight clip for balancing a rotor assembly of a gas turbine engine which includes a weight portion, and a first flange engaging portion and a second flange engaging portion extending from the weight portion. The weight portion and the first and second flange engaging portions define a flange receiving opening for receiving a flange of a disc of the rotor assembly. The first flange engaging portion is provided with a detent facing the second flange engaging portion and engageable with a mating groove provided on a face of the flange. At least one of the first and second flange engaging portions is elastically deformable so that the first and second flange engaging portions are elastically moveable away from one another to removably receive the flange in the flange receiving opening and engage the detent with the mating groove.