Vacuum Insulated Glazing Edge Seal Reheating to Prevent Foaming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing vacuum insulated glass (VIG) units face issues with gaseous inclusions forming during the edge seal melting process, leading to foaming and poor sealing, which affects manufacturing speed, quality, and durability.
Innovation Solution
A method involving the use of glass frit powder material heated to a softening temperature, applied and then re-heated without foaming, to create a dense edge seal between glass sheets, ensuring complete evacuation and strong sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the edge seal material is heated to melt and adhere to the glass sheets, then the sealing strength is improved, but gaseous inclusions form causing foaming and poor sealing quality
Solution Approach 1:
The patent applies preliminary action by pre-heating the edge seal material to a specific temperature range (175-225°C) before the main melting process. This preliminary heating reduces the moisture and volatile content in the material, preventing excessive foaming during subsequent heating and ensuring better sealing quality without compromising adhesion strength
Solution Approach 2:
The patent changes the temperature parameter in stages: first heating to 175-225°C for pre-drying, then to higher temperatures for melting and bonding. This controlled parameter change allows the material to undergo phase transitions gradually, eliminating gases before final setting, thus achieving both strong adhesion and low foaming
2Manufacturing precision
If the edge seal material is heated slowly to defoam gases, then the sealing quality is improved, but the manufacturing time increases
Solution Approach 1:
The patent performs the defoaming action in advance by pre-heating the edge seal material to 175-225°C before the main bonding process. This preliminary action removes most gases early, allowing the subsequent heating to be faster without causing excessive foaming, thus resolving the contradiction between quality and speed
Solution Approach 2:
By removing gases in the preliminary heating stage, the patent enables the main bonding process to proceed more quickly without the need for slow, gradual heating to prevent foaming. This skipping of the slow defoaming step during critical bonding achieves both high quality and fast production
3Object-generated harmful factors
If the edge seal material is pre-heated in a non-vacuum space, then the foaming during vacuum sealing is reduced, but the manufacturing process complexity increases
Solution Approach 1:
The patent combines the pre-heating and vacuum sealing operations into a single vacuum chamber system. The same chamber used for evacuation also performs the controlled pre-heating, eliminating the need for separate pre-heating equipment and reducing overall process complexity while effectively reducing foaming
Solution Approach 2:
The patent merges the pre-heating function with the vacuum sealing chamber, so that both operations occur in the same environment. This consolidation reduces equipment complexity and process steps while achieving the benefit of reduced foaming through controlled preliminary heating
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
This approach results in a high-quality VIG unit with reduced foaming, stronger sealing, and improved manufacturing efficiency by minimizing gaseous inclusions, allowing for faster and more reliable production.
Implementation Method 1
heating a glass frit powder material to a softening temperature (Tfrit−powder) to soften the glass frit powder material
Implementation Method 2
re-heating the applied glass frit powder material by use of at least one heat source
Implementation Method 3
evacuating the gap between the paired glass sheets in a vacuum chamber
Data Source
AI summary
A method of manufacturing a vacuum insulated glass unit, the method including providing a glass sheet assembly having a first and second glass sheets including inner major surfaces facing each other, support structures positioned therebetween, an edge seal including first and second seal layers in contact with each other, the edge seal being arranged at a peripheral edge so as to enclose a gap between the first and second glass sheets, where the edge seal includes edge seal material that has been outgassed in a heating step, and a getter arranged in the gap, where the method further includes re-heating the edge seal by means of an infrared laser so as to soften the edge seal, and evacuating and sealing the gap, where at least one of the first and second glass sheets includes a low-emission coating, and wherein the edge seal includes tellurium oxide, vanadium oxide, and bismuth oxide.