Vacuum Pump Continuous Ignition Source Flammable Mixture Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Vacuum pumps used in semiconductor tools face challenges in safely handling potentially flammable mixtures, as they require stringent leak integrity to prevent the creation of flammable atmospheres and risk hazardous ignition sources within the pump.
Innovation Solution
A multi-stage vacuum pump with a continuous ignition source located between adjacent stages is introduced to deliberately ignite fuel within the pumped fluid, regulating its concentration and confining reactions to prevent hazardous pressure rises and minimize flammable atmospheres.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a multi-stage positive displacement pump is used to pump flammable mixtures, then pumping capability is improved, but the risk of creating hazardous flame fronts and flammable atmospheres increases
Solution Approach 1:
The patent introduces a controlled ignition source that deliberately ignites fuel within the pump to convert the harmful potential for uncontrolled flame fronts into a beneficial controlled combustion process. This controlled ignition maintains fuel concentration below the lower explosion limit in the exhaust, transforming the hazard into a safety mechanism by preventing the accumulation of flammable mixtures.
Solution Approach 2:
By maintaining fuel concentration below the lower explosion limit through controlled ignition, the patent effectively creates an inert atmosphere in the pump exhaust. The continuous combustion process ensures that fuel does not accumulate to flammable levels, rendering the exhaust non-flammable and eliminating the hazard of flame fronts propagating through the exhaust lines.
2Reliability
If stringent leak integrity measures are implemented to prevent flammable atmospheres, then safety is improved, but device complexity increases
Solution Approach 1:
Instead of relying solely on complex leak prevention measures, the patent introduces a controlled ignition source that converts the potential hazard of leaked fuel into a beneficial controlled combustion process. This approach maintains safety by ensuring fuel concentration remains below flammable levels, thereby reducing the need for stringent and complex leak integrity measures.
3Reliability
If purge fluids are used to reduce fuel concentration below the lower explosion limit, then safety is improved, but operational costs increase
Solution Approach 1:
The patent employs a self-service mechanism where the controlled ignition source continuously combusts fuel within the pump, automatically maintaining fuel concentration below the lower explosion limit without requiring external purge fluids. The system serves itself by using the fuel present in the pumped mixture as the combustion fuel, eliminating the need for additional purge fluid consumption.
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 solution ensures that fuel concentration is maintained below the lower explosion limit, reducing the risk of flammable atmospheres and minimizing the need for purge fluids, thereby enhancing safety and reducing costs.
Implementation Method 1
a continuous ignition source for igniting fuel within a pumped fluid
Data Source
AI summary
A multi-stage vacuum pump comprises, between adjacent stages of the pump, a continuous ignition source for igniting a fuel within a pumped fluid. This can ensure that the concentration of the fuel in fluid exhaust from the pump is below its lower explosive limit.