Molded Rotatable Base With Blowing Agent Voids
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotatable bases for substrates, especially those used in cleaning, coating, or etching processes, face challenges with dimensional stability and uniform fluid distribution due to exposure to high temperatures during molding and machining, leading to loss of tolerances and inefficient fluid flow.
Innovation Solution
A rotatable base with a high ratio of open surface area and void volume, formed from molded thermoplastic with a blowing agent, featuring openings that facilitate uniform fluid distribution and mechanical interlocking with a porous pad, ensuring consistent fluid flow and dimensional stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the base is exposed to high temperatures during injection molding or post molding machining, then the base can be formed and finished, but dimensional tolerances and dimensional stability are lost
Solution Approach 1:
The patent changes the material parameter by using a thermoplastic polymer containing a blowing agent, which allows the base to be formed at lower temperatures through chemical expansion rather than thermal expansion. This avoids the high temperature exposure that causes dimensional instability while still achieving the desired void structure and finish.
Solution Approach 2:
The patent uses a composite material system consisting of thermoplastic polymer and blowing agent. The blowing agent provides internal pressure to create voids and expand the base structure during molding, eliminating the need for high temperature post-molding machining while maintaining dimensional stability through the composite's controlled expansion properties.
2Productivity
If the base has a high ratio of open surface area per area of base supporting the pad, then fluid distribution is improved, but dimensional stability during molding and machining deteriorates
Solution Approach 1:
The patent changes the manufacturing parameter from high-temperature mechanical machining to low-temperature chemical expansion using a blowing agent. This allows the base to achieve high open surface area ratios for improved fluid distribution while maintaining dimensional stability because the expansion occurs uniformly during molding without the localized stress and heat exposure that would distort the dimensional tolerances.
3Ease of manufacture
If conventional molding and machining processes are used, then the base can be manufactured, but the cost and complexity increase while dimensional stability decreases
Solution Approach 1:
The patent changes the fundamental parameter of how the base structure is created - instead of molding a solid base and then machining voids (which requires high precision and generates heat), the blowing agent chemically expands the base during molding to create voids. This single-step process reduces manufacturing complexity and cost while maintaining dimensional stability because the voids are formed uniformly during the molding process itself, eliminating subsequent high-temperature machining operations.
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 solution provides improved uniformity and efficiency in fluid distribution across substrates, maintaining dimensional stability and reducing pressure drop, while being cost-effective and lightweight, with enhanced mechanical properties for cleaning and coating processes.
Implementation Method 1
The base can be formed from a molded thermoplastic material with closed cell structure. In some embodiments, a blowing agent provides rigidity to high void volume base
Implementation Method 2
A rotatable base or brush core with a foam brush overlying the rotatable base or brush core can be used to distribute fluid across a substrate
Implementation Method 3
the porous pad, the pad being interlocked with one or more voids in the base
Data Source
AI summary
A rotatable base for a porous pad has openings that provide for improved flow distribution of a liquid in the base across a substrate. The rotatable base can be molded from a two piece mold and the openings can have draft angles to facilitate the molding process.