Diaphragm Flow Control Valve With Gap-Free Welded Fluid Path
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional flow rate control valves in semiconductor production struggle to maintain high cleanliness of fluids due to contamination from particles, especially with the stringent cleanliness standards required for advanced semiconductor processes.
Innovation Solution
A flow rate control valve design that integrates a diaphragm and a valve block with a piezoelectric actuator, where the peripheral portion of the diaphragm and the upper edge surface of the valve block are welded together to form a seamless, gap-free surface, preventing particle generation and accumulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the valve section and seat section are made of fluororesin and machined into prescribed shapes for high chemical resistance and cleanliness, then the valve can operate in semiconductor production environments, but the valve section and seat section wear away over time causing particle generation
Solution Approach 1:
The invention extracts the sealing function from the traditional valve section and seat section contact mechanism. Instead of relying on direct contact between machined fluororesin surfaces, the patent uses a valve element that seals against a valve seat through a different mechanism that eliminates the wear problem while maintaining chemical resistance and cleanliness requirements for semiconductor production
Solution Approach 2:
The invention inverts the traditional sealing approach by having the valve element seal against the valve seat in reverse fashion, where the valve element has a sealing surface that contacts the valve seat in a manner that prevents wear-related particle generation while maintaining effective sealing for high cleanliness applications
2Ease of operation
If the valve section is seated on the seat section to completely stop fluid flow, then flow control is achieved, but the abutting contact causes wear and particle occurrence over long-term usage
Solution Approach 1:
The invention extracts the wear mechanism from the sealing process by using a valve element design that achieves complete flow shutdown without the traditional abutting contact between valve section and seat section, thereby eliminating particle generation while maintaining flow control capability
Solution Approach 2:
The invention discards the traditional machined fluororesin valve section and seat section that wear away, and recovers the sealing function through a valve element and valve seat configuration that provides wear-free operation for complete flow control
3Ease of manufacture
If conventional flow rate control valves are used with machined fluororesin components, then the valve structure is simple to manufacture, but particles are generated from worn portions during long-term usage
Solution Approach 1:
The invention extracts the particle generation problem from the manufactured valve by using a valve element and valve seat configuration that eliminates wear-related contamination, while maintaining ease of manufacture through appropriate material selection and construction methods
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 configuration effectively reduces the occurrence of contamination and maintains high cleanliness of the controlled fluid by eliminating potential sources of particle generation and accumulation, while also enabling high-speed control of minute flow rates.
Implementation Method 1
by a minute pressure received on the diaphragm from an actuator
Implementation Method 2
a peripheral portion of the diaphragm and an upper edge surface of the valve block are integrated with each other by being welded together
Data Source
AI summary
A flow rate control valve for reducing contamination of a controlled fluid with particles, to maintain cleanliness of the fluid, and performing high-speed control of a minute flow rate. The valve includes a valve block, diaphragm, and actuator, wherein by a minute pressure received on the diaphragm from the actuator, the fluid that has flowed in one flew-path in an upstream portion of the valve block is discharged via a space between an inside surface of the valve block and an inside surface of the diaphragm from another path in a downstream portion of the valve block. A peripheral portion of the diaphragm and an upper edge surface of the valve block are integrated with each other by welding such that an inner peripheral surface of the diaphragm and an inner peripheral surface of the valve block are flush without a level difference or a-gap therebetween in a welded portion.