Accessory Gearbox Cover Linking Member for Vibration Damping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft accessory gearboxes are prone to dynamic vibrations and resonances due to the attachment of heavier engine accessories, which can interfere with engine operating speeds and create structural concerns, limited by weight and envelope constraints.
Innovation Solution
A planar linking member dynamically couples accessory devices mounted to the gearbox cover, mechanically interconnecting them independently of the cover to improve dynamic characteristics and reduce vibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If heavier accessories are mounted on the AGB cover, then the accessory gearbox can drive more engine accessories, but dynamic vibrations and resonances increase
Solution Approach 1:
The patent combines multiple accessory devices into a single integrated accessory gearbox assembly, where accessories are mounted on a common cover and interconnected through a linking member. This merging approach allows multiple accessories to be driven from a single gearbox while the linking member collectively manages vibrations from all accessories, reducing overall system complexity compared to separate gearboxes for each accessory.
Solution Approach 2:
The linking member acts as an intermediary element between multiple accessory devices mounted on the AGB cover. It mechanically connects accessories to each other and to the cover, serving as a mediator that transfers and distributes vibrational forces. This intermediary structure allows vibrations from individual accessories to be balanced and dampened collectively, reducing the harmful resonant effects that would occur if accessories operated independently.
2Weight of moving object
If the AGB cover is made thinner and lighter, then weight constraints are satisfied, but the cover becomes more prone to vibrations and resonances
Solution Approach 1:
The patent employs a composite structural approach where the AGB cover is made from a material that balances weight and vibrational resistance. The cover integrates multiple functional elements including accessory mounting surfaces, vibration damping features, and interconnection points for the linking member. This composite design allows the cover to remain thin and lightweight while incorporating vibration management capabilities that prevent excessive resonances despite the reduced mass.
Solution Approach 2:
The linking member introduces dynamic flexibility into the accessory mounting system. Rather than rigidly fixing accessories to the cover, the linking member allows controlled movement and vibration absorption. This dynamic connection enables the lightweight cover to accommodate vibrational forces from accessories without transmitting excessive resonances, effectively decoupling the weight reduction benefit from the vibration problem.
3Adaptability or versatility
If accessories are mounted on the AGB cover, then engine accessories can be driven, but structural concerns arise due to vibrations
Solution Approach 1:
The patent segments the accessory mounting system into distinct functional components: the AGB cover provides the mounting surface, the linking member provides the mechanical connection between accessories, and each accessory device is independently mounted. This segmentation allows vibrations from individual accessories to be isolated and managed separately while maintaining overall structural integrity. The linking member acts as a separate structural element that reinforces the cover rather than relying solely on the cover's strength.
Solution Approach 2:
The linking member incorporates vibration damping and shock absorption capabilities before vibrations can propagate through the AGB cover structure. By providing this cushioning effect at the source of vibrations (where accessories connect to the cover), the system prevents vibrational forces from accumulating and causing structural damage. This beforehand cushioning protects the structural integrity of the cover and its mounting points.
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 effectively reduces the load on the gearbox cover by tuning the vibration frequency and providing a damping effect, allowing for a lighter assembly and minimizing structural concerns.
Implementation Method 1
providing a damping effect
Data Source
AI summary
An accessory gearbox of an aircraft engine includes a cover mounted thereto. The cover defines a centrally extending axis and has an outer surface with accessory mounts disposed thereon. First and second accessory devices are mounted to the gearbox at first and second mounts spaced apart on the cover. A planar linking member dynamically couples the first accessory device to the second accessory device. The linking member extends transversally relative to the axis and has a first side opposite a second side with a first opening extending therethrough. The first opening is aligned and matingly receiving at least a portion of the first accessory device therethrough. The linking member has a second opening extending therethrough. The second opening is aligned and matingly receiving at least a portion of the second accessory device therethrough. The linking member mechanically interconnects the first and second accessory devices independently from the cover.