Rotary Valve Seal Assembly With Pressure-Responsive Biasing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary valves experience leakage due to poor sealing performance of static seals under high temperatures, pressures, and friction.
Innovation Solution
A seal assembly comprising a first and second seal ring with angled surfaces and an elastic ring positioned between them, which biases the seal rings radially inwardly and apart to enhance sealing around the shaft and within the rotary valve.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a static seal (e.g. O-ring) is positioned between the shaft and housing, then the sealing structure is simple, but the sealing performance deteriorates under high temperatures, pressures and friction
Solution Approach 1:
The seal assembly is divided into multiple components: a first seal ring, a second seal ring, and an elastic ring. Each component performs a specific sealing function - the first seal ring seals against the shaft, the second seal ring seals against the housing, and the elastic ring provides biasing force. This segmentation allows each component to be optimized for its specific function, improving overall sealing performance while maintaining reasonable structural complexity.
Solution Approach 2:
The elastic ring introduces dynamic characteristics to the sealing system. Unlike a static O-ring, the elastic ring can deform and adjust its biasing force in response to changing operating conditions such as temperature variations, pressure changes, and shaft rotation. This dynamic adaptation maintains effective sealing contact under varying conditions, resolving the contradiction between structural simplicity and sealing reliability.
2Reliability
If the elastic ring is arranged to act on the angled surfaces to bias the seal rings radially inwardly and apart, then the sealing force increases, but the device complexity increases
Solution Approach 1:
The elastic ring acts as an intermediary element between the first seal ring and the second seal ring. It transmits and transforms forces - converting radial compression into both radially inward biasing force (for shaft sealing) and axial separation force (for housing sealing). This intermediary mechanism achieves enhanced sealing force through a relatively simple elastic component rather than complex mechanical actuation systems.
Solution Approach 2:
The elastic ring utilizes changes in its elastic properties under different pressure conditions. As fluid pressure increases, the elastic ring deforms and generates increased biasing force on the seal rings. This parameter change (elastic deformation) automatically adjusts the sealing force to match operating conditions, providing high reliability without requiring complex control mechanisms.
3Reliability
If pressure applied on the elastic ring increases the biasing force, then the sealing performance improves under high pressure, but the device complexity increases
Solution Approach 1:
The elastic ring provides self-service functionality by automatically adjusting its biasing force in response to pressure changes. When fluid pressure increases, the elastic ring deforms and generates proportionally increased sealing force without requiring external control systems, actuators, or complex pressure-responsive mechanisms. This self-adjusting capability improves sealing performance under high pressure while maintaining relatively simple device structure.
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 seal assembly provides improved sealing performance by increasing the sealing force in response to increased fluid pressure, reducing leakage and maintaining effective sealing even under high-pressure conditions.
Implementation Method 1
an elastic ring disposed between the first seal ring and the second seal ring and in contact with the angled surfaces; wherein the elastic ring is arranged to act on the angled surfaces to bias the first seal ring and second seal ring radially inwardly and apart from one another
Implementation Method 2
a first seal ring having a first ring angled surface; a second seal ring having a second ring angled surface; wherein the elastic ring is arranged to act on the angled surfaces to bias the first seal ring and second seal ring radially inwardly and apart from one another
Implementation Method 3
pressure applied on a radially outward surface of the elastic ring increases the force biasing the first seal ring and second seal ring radially inwardly and apart from one another
Data Source
AI summary
A seal assembly for a shaft is arranged to extend around an outer circumferential surface of the shaft and includes: a first seal ring having a first ring angled surface; a second seal ring having a second ring angled surface; and an elastic ring disposed between the first seal ring and the second seal ring and in contact with the angled surfaces. The elastic ring is arranged to act on the angled surfaces to bias the first seal ring and second seal ring radially inwardly and apart from one another. The seal assembly can be part of a rotary valve.