Collapsible Protrusion Washer for Pivot Gap Compensation

Solution Overview

Problem

Existing fastener assemblies face issues with lateral play due to variations in material thickness and misalignments at pivot locations, which existing washers with protrusions fail to adequately address.

Innovation Solution

A washer design with circumferentially spaced, collapsible protrusions on its faces that deform to accommodate thickness variations, reducing lateral play by allowing for maximum gap compensation at pivot locations, constructed from materials like plastic, metal, or composites.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional rigid washers are used in pivot assemblies, then structural integrity is maintained, but lateral play occurs due to material thickness variations and misalignments

Engineering Contradiction:

Improvelateral play reductionVSAvoidwasher structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The washer is segmented into a rigid body portion and multiple collapsible protrusions. The rigid body maintains structural integrity and load-bearing capacity, while the collapsible protrusions independently deform to accommodate thickness variations and eliminate lateral play at pivot locations.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The protrusions are designed with deformable characteristics that allow their shape and volume parameters to change under compressive loading. This parameter change enables the protrusions to collapse and fill gaps caused by material thickness variations, reducing lateral play without compromising the overall washer structure.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If material thickness variations are accommodated, then lateral play is reduced, but manufacturing precision requirements increase

Engineering Contradiction:

Improvealignment stabilityVSAvoidprotrusion deformability control

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

Different regions of the washer have different properties: the body maintains rigid structural qualities for load-bearing, while the protrusions have localized deformable qualities for gap compensation. This local quality differentiation allows the washer to accommodate thickness variations without requiring high precision across the entire component.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The collapsible protrusions act as beforehand cushioning elements that anticipate and compensate for material thickness variations and misalignments before they cause lateral play. The protrusions are pre-designed to deform under normal operating loads, providing built-in compensation for expected dimensional inconsistencies.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Reliability

If collapsible protrusions are added to the washer, then gap compensation is improved, but structural integrity may be compromised

Engineering Contradiction:

Improvegap filling capabilityVSAvoidwasher body strength

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The washer is segmented into a rigid body portion and multiple collapsible protrusions. The rigid body maintains structural integrity and load-bearing capacity, while the collapsible protrusions independently deform to accommodate thickness variations and eliminate lateral play at pivot locations.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the washer have different properties: the body maintains rigid structural qualities for load-bearing, while the protrusions have localized deformable qualities for gap compensation. This local quality differentiation allows the washer to accommodate thickness variations without requiring high precision across the entire component.

Inventive Principle:

Principle #3Local quality

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 washer effectively reduces or eliminates lateral play by collapsing protrusions to fill gaps, ensuring proper alignment and stability in hinged or pivot assemblies despite material and dimensional inconsistencies.

Implementation Method 1

the protrusions exhibit deformable characteristics such that, upon exhibiting a laterally compressive force associated with the stacking assembly, result in collapse of the protrusions

Methodology Applied

Scientific EffectDeformation: Deformation

Data Source

PatentUS9222504B2Washer with collapsible protrusions for accommodating pivot gap material thickness

Publication Date: 2015.12.29 BAE IND INC

AI summary

A deformable washer incorporated into a pivot assembly including a support sector and a rotatable sector pivotally mounted to the support sector by aligning apertures in the sectors which receive a widthwise inserting pin. The washer includes a disk shaped body defining an open interior and such that the body is supported by the pin in a desired sandwiching arrangement between the sectors. Protrusions extend from either or both of first and second annular extending faces of the body exhibiting deformable characteristics such that, a laterally applied compressive force associated with the stacking assembly results in collapse of the protrusions without otherwise affecting the structural integrity of the underlying body and allows for variations in material thickness resulting in a lateral gap at the pivot while reducing instances of lateral play.