Capillary Meniscus Microfluidic Valve Without Moving Parts

The patent removes all moving parts from the valve structure entirely. Instead of using mechanical components that move to control flow, the invention uses a stationary constriction in the conduit where capillary forces naturally form a meniscus to block flow. The valve operation is achieved by breaking this meniscus through pressure application, eliminating the need for any moving components and thereby improving reliability while simplifying fabrication.

The patent replaces the mechanical system of moving parts with a capillary-based mechanism. The constriction in the conduit creates capillary forces that form a stable meniscus to control liquid flow without any mechanical movement. This substitution of mechanical components with capillary phenomena resolves the contradiction by eliminating the reliability issues and fabrication difficulties associated with moving parts.

The patent extracts and eliminates all moving parts from the valve design. The constriction is formed as a simple geometric feature in the conduit, which can be fabricated using standard microfabrication techniques without the need for complex assembly of moving components. This dramatically simplifies the manufacturing process while maintaining effective flow control.

By replacing the mechanical system with a capillary-based stationary structure, the patent enables easier fabrication. The constriction and meniscus formation rely on surface tension and capillary forces rather than precision-machined moving parts, making the device more amenable to standard microfabrication processes and reducing manufacturing complexity.

The patent uses hydraulic pressure to break the capillary meniscus and open the valve. A pressure source applies force to the liquid, and when the pressure exceeds the capillary pressure holding the meniscus in place, the meniscus breaks and flow is permitted. This hydraulic mechanism provides a simple and effective way to operate the valve without adding mechanical complexity.

The valve operation is achieved by changing the pressure parameter of the liquid. In the closed state, capillary pressure holds the meniscus in place. To open the valve, the applied pressure is increased until it overcomes the capillary pressure, causing the meniscus to break. This parameter-based control simplifies the operation mechanism while maintaining effective flow control.