Seal Assembly Biasing Member Retention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tandem circumferential shaft seals face challenges in maintaining axial spacing and preventing biasing member dislodgment during relative displacement, such as radial or angular movement, due to the limitations of traditional coil springs and housing designs.
Innovation Solution
The seal assembly features first and second annular seals with axially inwardly extending coupling and retaining pockets, respectively, where biasing members are disposed to exert axial force and remain coupled, with the retaining pocket's larger radial length allowing for radial displacement without dislodgment, ensuring the biasing members stay engaged and undamaged.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional coil springs are used to maintain axial spacing between seals, then axial spacing is maintained, but the biasing members may become dislodged during radial or angular displacement
Solution Approach 1:
The biasing member is nested within both the coupling pocket of the first seal and the retaining pocket of the second seal, creating a interlocked configuration where the biasing member cannot easily dislodge during radial or angular displacement while still allowing the seals to move relative to each other
Solution Approach 2:
The coupling and retaining pockets act as intermediary structures that mediate between the biasing member and the seals, providing controlled engagement points that prevent dislodgment while accommodating relative seal movement
2Reliability
If the biasing member is tightly constrained to prevent dislodgment, then reliability improves, but the seals cannot radially displace relative to each other
Solution Approach 1:
The retaining pocket is designed with dynamic characteristics that allow it to adapt its constraint level - providing tight retention in the axial direction while permitting radial displacement, thus accommodating both reliability and adaptability requirements
Solution Approach 2:
The coupling pocket and retaining pocket have different radial lengths, creating local quality differences where the retaining pocket provides greater radial clearance to accommodate seal displacement while the coupling pocket maintains adequate retention
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 design effectively maintains axial spacing and prevents biasing member dislodgment during seal displacement, ensuring reliable operation under various conditions like assembly, disassembly, and extreme engine conditions, while maintaining the integrity of the biasing members.
Implementation Method 1
at least one biasing member has a first end disposed within the at least one coupling pocket and an opposing, second end disposed within the at least one retaining pocket. The biasing member is configured to exert a generally axial biasing force on each one of the first and second seals.
Data Source
AI summary
A seal assembly includes first and second generally annular seals disposable about the shaft so as to be spaced apart axially along the shaft central axis. Each seal has an inner circumferential sealing surface and inner and outer axial sides, each inner axial side facing the other seal inner axial side. The first seal has at one or more coupling pockets extending inwardly from the first seal inner axial side and the second seal has one or more retaining pockets extending inwardly from the second seal inner axial side, each retaining pocket being aligned with one coupling pocket. One or more biasing members each have a first end disposed within one coupling pocket and an opposing, second end disposed within one retaining pocket, the biasing member being configured to exert an axial biasing force on each one of the first and second seals.