Refill unit and foam dispenser
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid dispenser systems struggle to effectively dispense liquids as foam by mixing them with air, often resulting in inconsistent foam quality and inefficient air-to-liquid ratios.
Innovation Solution
The development of sequentially activated multi-diaphragm foam pumps and refill units that incorporate a molded multi-chamber diaphragm with a liquid pump chamber and multiple air pump chambers, which are sequentially compressed by a rotatable drive mechanism to mix foamable liquids with air, creating a consistent foam product with adjustable air-to-liquid ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If air is injected into liquid to create foam, then foam dispensing is achieved, but inconsistent foam quality results
Solution Approach 1:
The pump chamber is segmented into multiple sealed chambers (first chamber for liquid, second and third chambers for air) within a single diaphragm structure. This segmentation allows independent control of liquid and air pumping sequences, ensuring consistent foam quality by preventing mixing and maintaining separate pressure zones for each phase.
Solution Approach 2:
Multiple pump chambers (liquid pump chamber and multiple air pump chambers) are merged into a single integrated diaphragm structure with shared walls. This merging reduces overall device complexity while maintaining the functional separation needed for consistent foam generation, as the chambers work in sequence within one compact unit.
2Reliability
If multiple air pump chambers are used to improve foam quality, then consistent foam is achieved, but device complexity increases
Solution Approach 1:
The diaphragm structure serves multiple functions simultaneously: it acts as the boundary for the liquid pump chamber, forms the walls of multiple air pump chambers, and provides the sealing structure for all chambers. This multi-functionality allows the device to achieve complex foam quality control without proportionally increasing overall structural complexity.
Solution Approach 2:
The multiple air pump chambers are nested within the overall diaphragm structure, with chamber walls shared between adjacent chambers. This nesting arrangement allows multiple functional chambers to be packed into a compact space, reducing device complexity while maintaining the air-to-liquid ratio control needed for consistent foam quality.
3Manufacturing precision
If sequential compression of multiple chambers is implemented, then air-to-liquid ratio control is improved, but device complexity increases
Solution Approach 1:
The drive mechanism implements periodic sequential compression of the liquid pump chamber followed by the air pump chambers in a repeating cycle. This periodic action naturally controls the air-to-liquid ratio by ensuring that a predetermined volume of air is delivered for each predetermined volume of liquid, achieving precise ratio control through temporal sequencing rather than complex spatial mechanisms.
Solution Approach 2:
The system controls foam quality by changing the temporal parameters of chamber compression (sequence and timing) rather than changing physical dimensions. By adjusting the periodic compression cycle of the diaphragms, the air-to-liquid ratio is precisely controlled, achieving manufacturing precision through parameter adjustment rather than complex mechanical adjustments.
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 solution enables the efficient creation and dispensing of foam with controlled air-to-liquid ratios, enhancing foam quality and reducing energy consumption per dispensed volume, while allowing for adjustable output volumes and densities.
Implementation Method 1
sequential compression of the liquid pump chamber and air pump chambers causing a predetermined volume of liquid to be pumped into a mixing chamber, followed by a predetermined volume of air to be pumped into the mixing chamber
Implementation Method 2
mixing chamber, located downstream of the liquid pump chamber and air pump chambers for mixing the liquid and air
Data Source
Figure 1
Figure 2
Figure 2A
AI summary
An exemplary refill unit for a foam dispenser comprises a container for holding foamable liquid, a foam pump secured to the container wherein the foam pump includes a housing, a molded multi-chamber diaphragm wherein the molded multi-chamber diaphragm comprises a liquid pump chamber and three air pump chambers, an inlet valve and an outlet valve. A mixing chamber is included and located downstream of the outlet valve for mixing foamable liquid from the liquid pump chamber with air from each of the three air pump chambers. In addition, a foam cartridge and an outlet for dispensing foam are also included.