Rotary Valve Liquid Dispenser for High-Accuracy Micro-Dosing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid dispensers for colorants, such as those described in US 2009/0236367, EP3249222A1, and CN 110 454 350, are complex, expensive, and suffer from low dosing accuracy due to high flow resistance and large volume between the piston and dosing outlet, requiring multiple steps for accurate dispensing.
Innovation Solution
A dispenser design featuring a piston pump with a rotatable valve core having a main and secondary dispense channel, where the secondary channel has a smaller diameter for precise dosing, and a return channel for excess liquid, allowing for high-speed dispensing of larger amounts and accurate dispensing of smaller amounts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single dispense channel is used in the valve core, then the device structure is simple, but the dosing accuracy for smaller amounts is insufficient
Solution Approach 1:
The valve core is segmented into multiple independent dispense channels (first dispense channel for larger amounts, second dispense channel for smaller amounts) with different diameters. This segmentation allows each channel to be optimized for its specific dispensing function, achieving high dosing accuracy for small amounts while maintaining simplicity for large amount dispensing through separate dedicated pathways.
2Measurement precision
If the volume between the piston and dosing outlet is large, then the pump can handle larger volumes, but the dosing accuracy for smaller amounts decreases
Solution Approach 1:
Different regions of the pump system are assigned different local qualities: the first dispense channel has a larger diameter optimized for high-volume dispensing, while the second dispense channel has a smaller diameter optimized for precise low-volume dispensing. This local differentiation allows the same pump system to achieve both high-volume efficiency and high-precision dosing without compromising either function.
3Measurement precision
If a small sized piston nested in a larger piston pump is used, then dosing accuracy is improved, but the construction becomes complex and expensive
Solution Approach 1:
A single piston pump unit is designed to perform multiple functions: dispensing large volumes through the first dispense channel and dispensing small volumes with high precision through the second dispense channel. This multi-functionality eliminates the need for separate pump units for different dispensing requirements, reducing overall system complexity while maintaining both high-volume capability and precise dosing accuracy.
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
The design achieves a robust and straightforward construction with high accuracy, enabling dispensing of less than 0.0015 ml, reducing flow resistance and improving color matching in paint tinting.
Implementation Method 1
the piston pump (12) comprises a cylinder (25) and a main piston (26) reciprocatingly fitted inside the cylinder (25)... enable withdrawal of liquid from the canister by means of the piston pump (12)
Implementation Method 2
The valve (11) comprises a valve housing (13) and a valve core (14) within the valve housing (13), the valve core (14) being rotatable about an axis of rotation (R)
Implementation Method 3
A secondary reciprocating member (40) fits reciprocatingly inside the axial channel section (47) of the secondary dispense channel (46)
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
Dispenser (10) for dispensing a liquid, in particular a colorant for paint. The dispenser comprises a piston pump and a valve. The piston pump (12) comprises a cylinder (25) and a main piston (26) reciprocatingly fitted inside the cylinder. The valve (11) comprises a valve housing (13) with a dispense opening (16), and a valve core (14) within the valve housing. The valve core is rotatable and comprises a main channel (42) and a secondary dispense channel (46) with a smallest diameter which smaller than the smallest diameter of the main channel (42). The secondary dispense channel comprises an axial channel section (47) communicating with the piston pump. A secondary piston (40) fits reciprocatingly inside the axial channel section (47) in the valve core (14).