Multi-Lip Sealing Device With Variable Interference For Grease Application

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Solution Overview

Problem

Existing sealing devices for rolling bearings, especially in flooded environments, face challenges in effectively preventing water intrusion and efficiently applying lubricant grease to multiple lips.

Innovation Solution

A sealing device with a first sealing member featuring a cylindrical part mounted to the outer member and an annular part extending inward, and a second sealing member with a sleeve and flange, including at least three axial lips made of elastic material, where the radially outer axial lip has greater interference than the inner axial lip, allowing for enhanced water prevention and easy grease application by supplying grease from the inner peripheral surface.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple axial lips are arranged in parallel to enhance water sealing ability, then the sealing performance against water intrusion is improved, but the complexity of grease application increases

Engineering Contradiction:
Improvewater sealing abilityVSAvoidgrease application complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The sealing device is divided into multiple axial lips (first axial lip, second axial lip, third axial lip) with different interference values. Each lip is segmented to perform specific sealing functions at different radial positions, allowing water to be blocked at multiple stages while enabling systematic grease application from the innermost to outermost lips.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different axial lips are assigned different interference values tailored to their specific positions and functions. The first axial lip has a first interference value, the second axial lip has a second interference value, and the third axial lip has a third interference value. This local differentiation optimizes both sealing performance and grease application efficiency at each specific location.

Inventive Principle:
Principle #3Local quality

2Ease of manufacture

If axial lips are made with uniform interference, then manufacturing is simplified, but grease application to inner peripheral surfaces becomes difficult

Engineering Contradiction:
Improvelip manufacturing simplicityVSAvoidgrease application ease
Core Design Contradiction:
Ease of manufactureVSEase of operation

Solution Approach 1:

Each axial lip is given a specific interference value suited to its position and function. The first axial lip has a first interference value, the second axial lip has a second interference value, and the third axial lip has a third interference value. This local differentiation optimizes both sealing performance and grease application efficiency at each specific location.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

Instead of applying grease from the outer side inward, the invention applies grease from the inner peripheral surface outward. The grease application device introduces grease through the inner peripheral surface of each axial lip, allowing grease to naturally distribute to the contact surfaces. This inverted approach simplifies the application process while ensuring proper lubrication.

Inventive Principle:
Principle #13The other way round (Inversion)

3Reliability

If more axial lips are arranged in a narrower area to improve sealing, then the sealing density is improved, but the space for grease application becomes more constrained

Engineering Contradiction:
Improvesealing densityVSAvoidavailable area for grease application
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

Instead of applying grease from the outer side inward, the invention applies grease from the inner peripheral surface outward. The grease application device introduces grease through the inner peripheral surface of each axial lip, allowing grease to naturally distribute to the contact surfaces. This inverted approach simplifies the application process while ensuring proper lubrication.

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The grease application system uses the rotational motion of the inner member to automatically distribute grease. As the inner member rotates, grease applied to the inner peripheral surfaces is automatically distributed to the contact areas between lips and the inner member, eliminating the need for complex manual application mechanisms.

Inventive Principle:
Principle #25Self-service

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 effectively prevents water intrusion and facilitates easy grease application, achieving a high work rate by allowing more axial lips in a narrower area and ensuring efficient lubrication of the sealing mechanism.

Implementation Method 1

at least three axial lips made from an elastic material that extends from the annular part toward the flange of the second sealing member

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

An axial lip disposed on a radially outer side has an interference that is greater than that of an axial lip disposed on a radially inner side

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3882497B1Sealing device and grease adherence method
Publication Date: 2024.08.21 NOK CORP
  • EP3882497B1 patent drawingFigure 1
  • EP3882497B1 patent drawingFigure 2~3
  • EP3882497B1 patent drawingFigure 4~5

AI summary

A sealing device is disposed between an inner member and an outer member that rotate relative to each other to seal a gap between the inner member and the outer member of the sealing device, and includes a first sealing member including a cylindrical part to be mounted to the outer member, and an annular part that extends radially inward from the cylindrical part toward the inner member; and a second sealing member including a sleeve to be mounted to the inner member, and a flange that extends radially outward from the sleeve, the flange facing the annular part of the first sealing member. The first sealing member includes at least three axial lips made from an elastic material that extends from the annular part toward the flange of the second sealing member. An axial lip disposed radially outer side has an interference that is greater than that of an axial lip disposed radially inner side.