Automatic Disconnect Coupling Tuned for Generator Unbalance

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Solution Overview

Problem

Conventional generator disconnect mechanisms in aircraft electrical systems require manual operation and lack an automatic solution for mechanically disconnecting generators from their rotation sources, especially when rotational unbalance occurs, which can lead to vibration, noise, and potential damage.

Innovation Solution

An automatic disconnect coupling system that includes a plunger and retainer mechanism, dynamically coupled with a solenoid and damping arrangement, which automatically disconnects the generator from the prime mover when rotational unbalance exceeds a predetermined level, using a spring-mass system tuned to the rotational speed to unlock the coupling and cease power generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Extent of automation

If manual disconnect operation is used, then device complexity is reduced, but automation level and operational safety deteriorate

Engineering Contradiction:

Improveautomatic disconnect operationVSAvoiddisconnect mechanism complexity

Core Design Contradiction:

Extent of automationVSDevice complexity

Solution Approach 1:

The disconnect mechanism automatically detects rotational unbalance through vibration sensing and self-actuates the disconnect plunger without external intervention. The system serves itself by using its own operational parameters (vibration levels) to trigger the disconnect action, eliminating the need for manual monitoring and operation.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces manual mechanical operation with an automated system that uses vibration sensors and solenoid actuators. The mechanical disconnect action is triggered by an electromechanical system that detects abnormal vibration patterns and automatically actuates the disconnect mechanism.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If generator remains connected during rotational unbalance, then productivity is maintained, but harmful factors and reliability deteriorate

Engineering Contradiction:

Improvegenerator system reliabilityVSAvoidvibration and collateral damage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The system continuously monitors vibration levels during generator operation and uses this feedback to determine when disconnect action is required. The vibration sensors provide real-time information about rotational unbalance, and when thresholds are exceeded, the system automatically triggers disconnect to prevent damage.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system uses the harmful vibration caused by rotational unbalance as the triggering mechanism for disconnect. The very vibration that indicates a problem and could cause damage is converted into the signal that initiates protective action, turning a harmful indicator into a beneficial trigger.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Ease of operation

If automatic vibration-based disconnect is implemented, then operational safety is improved, but device complexity and manufacturing difficulty increase

Engineering Contradiction:

Improveautomatic disconnect operationVSAvoidmanufacturing complexity

Core Design Contradiction:

Ease of operationVSEase of manufacture

Solution Approach 1:

The disconnect mechanism is divided into separate functional modules: vibration sensors, signal processing circuitry, solenoid actuators, and the disconnect plunger mechanism. This segmentation allows each component to be manufactured and tested independently, then assembled into the complete automatic disconnect system.

Inventive Principle:

Principle #1Segmentation

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 automatic disconnect coupling system effectively reduces collateral damage to generator and gearbox static structures by automatically disconnecting the rotor when unbalance occurs, preventing excessive loads and potential in-flight engine shutdowns, while simplifying maintenance and enhancing operational safety.

Implementation Method 1

A solenoid is dynamically coupled to the input member

Methodology Applied

Scientific EffectSolenoid: Solenoid

Implementation Method 2

A damping arrangement is interposed between the solenoid and the retainer

Methodology Applied

Scientific EffectDamping: Damping

Implementation Method 3

A retainer is provided which retains the plunger in the disengaged position. A spring-mass system is provided with a fundamental frequency which is tuned to a predetermined value corresponding to a normal operating speed of the rotor portion

Methodology Applied

Scientific EffectResonance: Resonance

Data Source

PatentEP3425230B1Automatically actuated disconnect couplings

Publication Date: 2024.02.28 HAMILTON SUNDSTRAND CORP

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AI summary

An automatic disconnect coupling (100) includes a retainer (130) and a biasing member. The biasing member is coupled to the retainer (130) and is arranged to communicate excitation from a generator input member (110) to the retainer (130). The retainer (130) and the biasing member have a fundamental frequency tuned to the rotational speed of the generator input member (110) to automatically disconnect the input member (110) from a drive member (18) when rotating unbalance of the input member exceeds a predetermined level.