Variable Set Blade Bushing Bevel Groove Rotation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing bushings for variable set blades in high-pressure compressors experience premature wear and potential perforation due to the clearance between the bushing and the circumferential groove, which allows rotation force to be transmitted and prevents complete blocking during blade orientation.
Innovation Solution
A bushing design with beveled sides that contact the circumferential groove edges to block rotation while allowing blade pivoting, preventing edge damage and extending the ring's lifespan by using a cylindrical part and a base with beveled sides that engage the groove edges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a clearance is present between the bushing and the circumferential groove to enable assembly, then the bushing can be easily assembled in the groove, but the clearance allows rotation force to be transmitted causing premature wear and perforation of the groove edges
Solution Approach 1:
The bushing base is pre-formed with beveled sides during manufacturing, creating built-in rotation-blocking features that engage with the groove edges before operation begins. This preliminary geometric configuration ensures that when the bushing is assembled in the groove, the beveled sides automatically prevent rotation force transmission, eliminating wear issues without requiring additional assembly steps or modifications.
Solution Approach 2:
The bushing base features localized beveled surfaces on specific sides, creating differentiated functional zones. The beveled sides provide rotation-blocking contact surfaces that engage with the groove edges, while other portions of the base maintain clearance for assembly. This local geometric modification concentrates the rotation-prevention function at specific contact points, preventing wear at the groove edges while preserving overall assembly ease.
2Reliability
If the bushing is completely blocked in rotation to prevent wear, then the groove edges are protected from damage, but the blade cannot pivot within the bushing
Solution Approach 1:
The bushing base is segmented into multiple sides with different geometric features. At least two opposite sides are equipped with beveled surfaces for rotation blocking, while other sides maintain clearance or different profiles. This segmentation allows the bushing to simultaneously achieve rotation prevention (through beveled side engagement) and blade pivoting capability (through clearance on non-beveled sides), resolving the contradiction between wear protection and adaptability.
Solution Approach 2:
The bushing base employs asymmetric geometry where only specific sides (at least two opposite ones) have beveled surfaces, while other sides differ in profile. This asymmetric design creates directional functionality: the beveled sides engage with groove edges to block rotation, while the asymmetric clearance zones allow blade pivoting motion. The asymmetry enables simultaneous achievement of wear protection and pivoting capability by directing different functions to different spatial zones.
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 beveled bushing design effectively blocks rotation without damaging the groove edges, allowing blade pivoting and increasing the ring's lifetime by preventing wear and perforation.
Implementation Method 1
When the blade is rotated, the bushing is driven in rotation by friction. Thanks to the specific shape of the bushing for a variable set blade according to an embodiment of the invention, when the bushing is rotated by friction, said bevel comes rapidly into contact with one of the edges of said circumferential groove of said ring so as to block in rotation said bushing.
Data Source
AI summary
A bushing for a variable set blade includes a cylindrical part configured to receive the blade, the root of the blade being able to rotate in the cylindrical part, and a base including: a first side able to be put in contact with a first edge of a circumferential groove of the ring, and/or a second side able to be put in contact with a second edge of the circumferential groove of the ring. At least one of the first side or second side of the base includes at least one bevel through which the first side or the second side is able to be put in contact with one of the first edge or second edge of the circumferential groove so as to block the bushing in rotation. The invention finds a particularly interesting application in the field of aircraft.