Epicyclic Reduction Gear Layout for Compact Turbomachine Accessories
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional turbomachine architectures with a planetary gear reducer are not compatible with all configurations, particularly when the turbine shaft is guided relative to the fan shaft upstream of the reduction gear, limiting the placement of accessory equipment and increasing the size of the nacelle.
Innovation Solution
A mobile sun gear and a rotatable crown carrier drive a fan shaft, with a stationary satellite carrier and a rotor attached to the planet carrier, allowing for flexible equipment placement and reducing the size of the accessory gearbox (AGB) box.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the equipment is attached to the AGB box, then the electrical or hydraulic power available is increased, but the size of the nacelle must be increased to accommodate the larger AGB box
Solution Approach 1:
The patent merges the equipment (such as alternator-starter or pump) directly into the reduction gear structure by attaching it to the planet carrier bearing, rather than keeping it separate in the AGB box. This integration allows the equipment to share the structural space of the reduction gear, thereby increasing power availability without proportionally increasing nacelle volume.
Solution Approach 2:
The equipment is nested within the existing reduction gear assembly by mounting it on the planet carrier bearing, which is already part of the reducer structure. This nesting approach allows the equipment to occupy space within the existing mechanical assembly rather than requiring additional external space in the nacelle.
2Stability of the object's composition
If the turbine shaft is guided relative to the fan shaft upstream of the reduction gear, then the structural stability is improved, but the compatibility with conventional reducer architectures is reduced
Solution Approach 1:
The patent creates a universal mounting solution for the equipment on the planet carrier bearing that can accommodate different turbomachine architectures, including those with guided turbine shafts. The mounting mechanism is designed to be architecture-agnostic, allowing the same reduction gear design to be adapted to various structural configurations without requiring architecture-specific modifications.
3Volume of stationary object
If the equipment is placed upstream of the solar, then the AGB box size is reduced, but the placement is not compatible with all turbomachine architectures
Solution Approach 1:
The patent moves the equipment mounting location from the traditional upstream position (one-dimensional placement along the shaft axis) to the planet carrier bearing location, which is in a different spatial dimension within the reduction gear assembly. This dimensional relocation allows the equipment to be positioned in available space without interfering with the guided turbine shaft configuration, thereby achieving compact AGB box design while maintaining architecture compatibility.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed is an epicyclic reduction gear (15) for a turbomachine comprising: - a sun gear (16) that is able to rotate about a first axis (A); - a ring gear (17) surrounding the sun gear (16) and able to rotate about the first axis (A), the ring gear (17) being secured to a ring gear carrier (18) capable of rotating a fan shaft; - at least one planet gear (19) that is able to rotate about a second axis (B), the planet gear (19); - a stationary planet carrier (20), the planet gear (19) being guided in rotation about the second axis (B) relative to a bearing (35) of the planet carrier (20); - a piece of equipment (22) comprising a rotor (23); characterised in that the piece of equipment (22) is attached to the bearing (35) of the planet carrier (20) and the rotor (23) of the piece of equipment (22) is rotated by the ring gear carrier (18).