Gearbox Connection Mechanical Fuse for Gas Turbine Torque Overload
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engines with gearboxes face challenges in managing high torque transmission, which can lead to damage and fatigue in the load path from the gearbox to the stationary structure, necessitating an efficient torque limiting mechanism to prevent further damage.
Innovation Solution
A torque limiting device featuring a mechanical fuse with predetermined material weakening, designed to fail under shear stress, is integrated into the connection structure between the gearbox and the stationary structure, ensuring controlled rupture and preventing damage from excessive torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a robust connection structure is used to transmit high torque from the gearbox to the stationary structure, then the torque transmission capability is improved, but the risk of damage and fatigue to components in the load path increases
Solution Approach 1:
The patent introduces a mechanical fuse as an intermediary element in the connection structure between the gearbox and stationary structure. This mechanical fuse acts as a mediator that absorbs excessive torque through controlled rupture, protecting other components from damage. The fuse is positioned in the load path and designed to fail at a predetermined torque threshold, thereby mediating between the high torque transmission requirement and the protection of vulnerable components.
Solution Approach 2:
The patent converts the potentially harmful effect of excessive torque into a beneficial protective mechanism. By designing a mechanical fuse that intentionally fails under extreme torque conditions, the harmful overload is transformed into a controlled safety feature. The fuse's failure mode is engineered to protect other expensive and critical components, turning what would be a damaging event into a protective action that saves the overall system.
2Strength
If the connection structure is designed to withstand extreme torque, then component strength is improved, but the weight of the connection structure increases
Solution Approach 1:
The patent segments the connection structure into functional zones: a robust section for normal torque transmission and a weakened mechanical fuse section for overload protection. This segmentation allows the majority of the connection structure to be optimized for strength without requiring the entire structure to be oversized for extreme torque events. The mechanical fuse segment is deliberately designed with reduced cross-section to fail at a predetermined torque threshold.
Solution Approach 2:
The patent applies parameter changes by creating a localized variation in the cross-sectional area of the connection structure. The mechanical fuse has a reduced cross-section compared to the rest of the connection structure, creating a predetermined weak point. This parameter change allows the structure to maintain adequate strength for normal operation while providing a controlled failure mode for overload protection, avoiding the need to increase the overall weight of the entire connection structure.
3Measurement precision
If a mechanical fuse with predetermined weakening is introduced to limit torque, then torque control precision is improved, but the device complexity increases
Solution Approach 1:
The mechanical fuse is designed to be self-regulating and self-limiting based on its geometric design. The predetermined weakening creates a specific cross-sectional area that determines the torque threshold for failure. Once the torque exceeds this threshold, the fuse automatically ruptures without requiring external control systems, sensors, or active intervention. This self-service approach provides precise torque control while minimizing additional complexity.
Solution Approach 2:
The patent uses parameter changes in the geometric design of the mechanical fuse to achieve precise torque control. By carefully designing the cross-sectional area and shape of the weakened section, the torque threshold for failure can be precisely predetermined. This geometric parameter approach provides accurate torque limiting without requiring complex control systems, electronics, or active monitoring, thereby maintaining simplicity while achieving precision.
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 mechanical fuse effectively limits torque, preventing damage and reducing weight by allowing controlled failure under shear stress, thus ensuring the structural integrity and safety of the gas turbine engine components.
Implementation Method 1
The mechanical fuse is designed to release only under shear stress which implies that it is designed e.g. not to give way under bending moments or forces.
Data Source
AI summary
The invention relates to a torque limiting device in a torque bearing connecting structure between a gearbox and a stationary structure in a gas turbine engine, wherein the torque limiting device comprises a mechanical fuse in the connection structure comprising an at least partially circumferential weakening of the material. The invention also relates to a gas turbine engine.