Offset Rotary Gear Actuator for Thin Aircraft Wing Sections
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional rotary geared actuators (RGAs) are too large to be fitted into the thin wing sections of aircraft, particularly at the leading edge, due to the central positioning of the drive transmission shaft which increases the overall diameter and prevents their use in thin wing applications.
Innovation Solution
A rotary geared actuator design with a laterally offset drive transmission shaft and an offset gearbox arrangement, allowing the gears to be positioned around a sun gear connecting shaft, reducing the overall diameter while maintaining torque transmission efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the drive transmission shaft is positioned centrally in conventional RGAs, then the structure is simple and easy to manufacture, but the overall diameter becomes too large to fit into thin wing sections
Solution Approach 1:
The patent applies dimensionality change by offsetting the drive transmission shaft from the central axis to a lateral position. This shifts the gear arrangement from a conventional central configuration to an offset configuration, reducing the actuator's overall diameter in the radial direction while accommodating the necessary gear components in the axial direction. The offset gearbox arrangement allows the RGA to fit into thin wing sections by changing the spatial distribution of components along different dimensions.
2Volume of moving object
If the drive transmission shaft is offset laterally, then the actuator diameter is reduced for thin wing sections, but the gear positioning and transmission mechanism become more complex
Solution Approach 1:
The patent employs nesting by positioning the sun gear, planet gears, and ring gear in a compact epicyclic arrangement around the offset drive transmission shaft. The planet gears are nested between the sun gear and the ring gear, allowing multiple gear components to occupy a smaller radial space. This nested configuration reduces the overall actuator diameter while maintaining effective torque transmission, though it does increase manufacturing complexity compared to simpler gear arrangements.
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
Enables the use of RGAs in thinner wing sections, reducing aircraft weight and improving aerodynamics by minimizing the actuator's diameter and allowing for more compact designs in various mechanical applications.
Implementation Method 1
means for translating said rotation of said drive transmission shaft to said gears so as to cause rotation of said gears about said first central longitudinal axis X'
Implementation Method 2
The offset gearbox arrangement may comprise an epicyclic, combined ring gear and housing that is connected to the laterally offset drive transmission shaft as well as connected to the sun gear connecting shaft
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A rotary geared actuator RGA (100) is described herein comprising: an actuator body comprising: a gear or gears (140, 150, 160a, 160b) and means configured to rotate said gear or gears about a first central longitudinal axis X'; and a drive transmission shaft (210) extending along a second central longitudinal axis X", and means for rotating said drive transmission shaft (210) about said central longitudinal axis X", and means for translating said rotation of said drive transmission shaft (210) to said gears (140, 150, 160a, 160b) so as to cause rotation of said gears (140; 150; 160a, 160b) about said first central longitudinal axis X', and wherein said second central longitudinal axis X" of said drive transmission shaft (210) is laterally offset from said first central longitudinal axis X'. A method for manufacturing such a RGA is also described.