High flexibility sealing device, in particular for household appliances
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydraulic sealing devices in washing machines fail to maintain a reliable static seal between the annular protection plate and the housing due to varying assembly tolerances and differential thermal expansion, leading to washing fluid seepage and reduced bearing life.
Innovation Solution
A sealing device with an elastomeric annular element featuring a V-shaped sealing lip and an annular spur, which allows for elastic deformation and maintains contact even with minimal axial distance, ensuring a consistent seal despite variations in assembly tolerances and thermal expansion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If static sealing lips are added to prevent washing fluid seepage, then sealing reliability improves, but the device becomes more sensitive to variations in axial distance due to assembly tolerances and thermal expansion
Solution Approach 1:
The sealing lip is designed with elastic material and a specific geometric configuration (convex side facing the annular plate) that allows it to dynamically adapt its position and contact pressure in response to variations in axial distance, assembly tolerances, and thermal expansion, maintaining reliable sealing without requiring precise pre-setting of the seal gap
Solution Approach 2:
The elastic material properties and the geometric parameters of the sealing lip (particularly the convex configuration) enable the seal to change its physical state and contact characteristics in response to temperature changes and mechanical variations, maintaining sealing effectiveness across different operating conditions
2Reliability
If the axial distance between the housing front face and the annular plate is reduced to improve sealing, then sealing effectiveness improves, but assembly tolerances and thermal expansion cannot be accommodated
Solution Approach 1:
The elastic sealing lip dynamically adjusts its contact pressure and position based on the actual axial distance, accommodating tolerance variations and thermal expansion without requiring a precisely controlled minimal gap, thereby maintaining sealing effectiveness while allowing for practical assembly tolerances
3Stability of the object's composition
If rigid sealing lips are used to ensure consistent contact, then sealing stability improves, but the seal fails to accommodate differential thermal expansion and assembly tolerances
Solution Approach 1:
The elastic material allows the sealing lip to change its physical parameters (shape, contact pressure, position) in response to temperature changes and mechanical variations, maintaining stable sealing contact across different operating conditions without requiring rigid precision
Solution Approach 2:
The sealing lip transitions from a static rigid component to a dynamic elastic component that continuously adapts its configuration to maintain optimal contact with the annular plate despite thermal expansion, assembly tolerances, and operational variations
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 sealing device provides an optimal and reliable hydraulic seal, preventing washing fluid infiltration and extending the life of the rolling bearing by adapting to varying conditions through the V-shaped lip and annular spur configuration.
Implementation Method 1
an elastomeric annular element featuring a V-shaped sealing lip and an annular spur, which allows for elastic deformation and maintains contact even with minimal axial distance
Implementation Method 2
A sealing device is mounted between a front face of the housing and the annular plate, statically inserted inside the housing, in front of the seat for the rolling bearing, and cooperates by means of one or more sliding contact lips with a cylindrical side wall of the bell member, exerting a dynamic hydraulic sealing action thereon
Data Source
AI summary
A sealing device is provided for exerting a static hydraulic sealing action between two mechanical elements arranged facing each other and between which there is a variable axial distance. The sealing device includes an annular elastomeric element having a first sealing lip extending cantilevered radially outward from a support element and formed by adjacent annular portions. The first sealing lip has first and second branches arranged at an angle relative to each other so as to form in radial cross section a V-shape oriented radially and converging in a direction away from an axis of symmetry of the elastomeric annular element. The first branch is provided with a cantilevered annular spur forming a fulcrum designed to open or close the V-shape depending on the variable axial distance.