Dual-Valve Microfluidic Dispensing for Shorter Fluid Pulses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing apparatuses for metered dispensing of microfluidic amounts in the picoliter and microliter range lack flexibility in controlling the opening and closing times of the discharge line, limiting the variability and precision of fluid dispensing, especially in applications like tattooing and microfluidics.
Innovation Solution
An apparatus with a combination of a first valve (closer) and a second valve (opener) in the discharge line, controlled by a device that can adjust the minimum opening and closing times to enable shorter fluid pulses and improved variability in dispensing, allowing for precise metering of microfluidic amounts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If a single valve (opener or closer) is used to control the discharge line, then the valve structure is simple, but the minimum opening time or closing time cannot be shortened below the valve's inherent minimum time
Solution Approach 1:
The discharge line control is segmented into two independent valve units: a first valve unit (closer) that closes the discharge line and a second valve unit (opener) that opens it. Each valve unit operates independently with its own actuator, allowing the system to overcome the minimum opening/closing time limitations of a single valve by strategically sequencing the activation of both valves.
2Adaptability or versatility
If the valve opening and closing times are fixed by the valve characteristics, then the valve operation is reliable, but the flexibility and variability in fluid dispensing are limited
Solution Approach 1:
The system dynamically adjusts the opening and closing times of the discharge line by independently controlling the activation timing of the first and second valve units. The control unit can vary the duration for which each valve remains open or closed, enabling adaptive fluid dispensing that responds to different operational requirements while maintaining reliable valve operation through structured control sequences.
3Manufacturing precision
If a single valve is used to control fluid flow, then the device structure is simple, but the precision and variability in metered dispensing of microfluidic amounts are limited
Solution Approach 1:
The fluid control function is segmented across two valve units with independent actuators, allowing precise control over the timing and duration of fluid discharge. This segmentation enables the system to achieve higher precision in metered dispensing of microfluidic amounts by independently optimizing the opening and closing phases of fluid flow through coordinated control of both valve units.
Data Source
AI summary
Metered dispensing of a microfluidic amount of fluid from a reservoir comprises a pressure device which applies a discharge pressure for fluid ejection via a discharge line through a valve arrangement. The valve device has a first valve with a minimum closing time and a second valve with a minimum opening time. A control device provides control signals for operation for metered dispensing of the amount of fluid as follows: a shortened minimum opening time for freeing the discharge line for the fluid flow, which time is shorter than the minimum opening time of the second valve; and a shortened minimum closing time for closing the discharge line for the fluid flow, which time is shorter than the minimum closing time of the first valve. Furthermore, a hand-held device for locally piercing human or animal skin is disclosed.