Drop Generation Device Using Capillary Channel Segregation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current dosing systems face challenges in non-contact dosage of highly viscous media and melted media at high temperatures, as well as the need for further reduction in dosage volume, particularly in three-dimensional printing applications where precise and reproducible drop generation is required.
Innovation Solution
A device and method utilizing a two-phase flow system with a reservoir and channel design where capillary forces hold the primary liquid in the main region and a secondary fluid in the sub-region, allowing for pneumatic or hydraulic pressure to generate a free-flying drop, enabling efficient drop generation and tear-off within the nozzle or channel, independent of the fluid's physical characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If contact dosage with a needle is used, then the liquid can be delivered directly to the target area, but the needle is at high risk of damage and cannot be used in non-topographically even areas
Solution Approach 1:
The patent introduces a drop as an intermediary carrier between the liquid reservoir and the target area. Instead of direct contact dosage with a needle, the liquid is first formed into a drop that can be transported and deposited without exposing a fragile needle to damage or complex terrain.
Solution Approach 2:
The invention extracts the liquid from the needle tip and forms it into a free-flying drop. This separates the delivery function from the containment function, allowing the liquid to be delivered without requiring a physical needle to maintain contact with the target area.
2Productivity
If open-jet tear-off method is used, then continuous liquid jet can be generated, but the jet disintegrates into drops of the same size and interval which is not desired when single drops are needed
Solution Approach 1:
The patent applies periodic pressure pulses to the liquid reservoir, creating a controlled rhythm of drop formation. This periodic actuation allows single drops to be generated on demand rather than continuous jet disintegration, enabling precise control over drop generation timing and frequency.
Solution Approach 2:
The invention uses dynamic pressure control to transition from static liquid hold-up to dynamic drop ejection. By varying the pressure applied to the liquid, the system can control whether liquid remains held in the channel or is ejected as a drop, enabling flexible drop-on-demand generation.
3Manufacturing precision
If inertia-driven single drop dosage is used, then single drops can be generated by pressure pulse, but the method does not work with highly viscous media
Solution Approach 1:
The patent employs pneumatic pressure application through a gas channel to actuate drop generation. This pneumatic approach provides sufficient force to overcome high viscosity resistance, enabling the system to handle highly viscous media that cannot be processed by conventional inertia-driven methods.
Solution Approach 2:
The invention pre-fills the channel with liquid before drop generation. This preliminary filling ensures that the liquid is already positioned and pressurized within the channel, creating optimal conditions for subsequent drop ejection even with highly viscous media that require advance preparation.
4Volume of moving object
If drop generation is performed from a certain distance, then smaller drops can be deposited on target area, but contact dosage requires the tool to be brought very close to the target area
Solution Approach 1:
The patent replaces direct mechanical contact dosage with a pneumatic-dynamic drop ejection system. Drops are generated and propelled through fluid dynamics rather than mechanical manipulation, allowing deposition from a distance while maintaining precise control over drop size and placement.
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 allows for precise and reproducible generation of small drops, including from highly viscous media, with reduced adhesion and oxidation risks, enabling efficient dosing in three-dimensional printing and other applications by defining drop volume through nozzle geometry and using a secondary fluid for pressure and protection.
Implementation Method 1
the flow cross-section includes a main region and at least one sub-region extending from the main region, designed such that the primary liquid as first phase of the two-phase channel can be held in the main region by capillary forces, and the secondary fluid as second phase of the two-phase channel can be held in the sub-region by capillary forces
Implementation Method 2
the pressure generation device is implemented to apply in the reservoir a pneumatic or hydraulic pressure to the primary liquid, whereby the same is moved along the channel and output at a second end of the channel as free-flying drop
Implementation Method 3
the pressure generation device is implemented to apply in the reservoir a pneumatic or hydraulic pressure to the primary liquid
Data Source
AI summary
A device for generating a drop of a primary liquid is described, including: a reservoir fillable with the primary liquid, a pressure generation device for generating a hydraulic pressure on the primary liquid, at least one inlet channel for introducing a secondary fluid, and a channel having a flow cross-section transverse to a main flow direction, wherein the flow cross-section includes a main region and at least one sub-region extending from the main region, designed such that the primary liquid can be held in the main region by capillary forces, and the secondary fluid can be held in the sub-region by capillary forces, wherein the reservoir is fluidically connected to a first end of the channel via an output opening, and the at least one inlet channel is also fluidically connected to the channel, and wherein the pressure generation device is implemented to apply a hydraulic pressure to the primary liquid, whereby the same is moved along the channel and output at a second end of the channel as free-flying drop.