Withdrawal-Stroke Piston Pump for Foam and Mist Dispensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing liquid dispensers fail to efficiently dispense liquids as foam or mist, requiring excessive liquid usage and often leading to runoff on surfaces.

Innovation Solution

A pump assembly with a first pump drawing liquid from a reservoir and a second pump that receives the discharge from the first pump, incorporating a piston movable in both inner and outer chambers, allowing for coordinated liquid and air discharge to produce foam or mist through a foam generator or nozzle.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If liquid is dispensed in liquid form, then dispensing is simple, but excessive liquid is required and runoff occurs

Engineering Contradiction:
Improvedispensing simplicityVSAvoidliquid runoff
Core Design Contradiction:
Ease of operationVSLoss of substance

Solution Approach 1:

The invention changes the physical state parameter of the dispensed liquid by mixing it with air to create foam or mist. This transforms the liquid from a pure liquid state to a foamed or atomized state, which reduces runoff and improves application efficiency while maintaining ease of dispensing through the pump mechanism

Inventive Principle:
Principle #35Parameter changes

2Loss of substance

If liquid is dispensed as foam, then liquid usage is reduced and runoff is minimized, but device complexity increases

Engineering Contradiction:
Improveliquid usage efficiencyVSAvoidpump assembly structure
Core Design Contradiction:
Loss of substanceVSDevice complexity

Solution Approach 1:

The invention merges the functions of liquid pumping and air mixing into a single integrated pump assembly. The piston mechanism simultaneously handles liquid displacement from the reservoir and air intake, combining multiple functions (liquid pumping, air mixing, foam generation) into one device, thereby reducing overall system complexity while achieving foam dispensing

Inventive Principle:
Principle #5Merging (Combining)

3Device complexity

If a single piston is used for both inner and outer chambers, then device complexity is reduced, but coordination of liquid and air discharge becomes difficult

Engineering Contradiction:
Improvepiston configurationVSAvoiddischarge coordination
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The invention segments the pumping chambers into an inner chamber and an outer chamber, each with its own piston movement phase. The inner piston and outer piston are configured to move out of phase with each other, creating distinct discharge timing for liquid and air. This segmentation allows independent control of each chamber while using a unified piston assembly, ensuring reliable coordination of foam and mist discharge

Inventive Principle:
Principle #1Segmentation

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 solution reduces liquid usage by creating foam or mist, minimizing runoff and enhancing dispensing efficiency while allowing for precise control over liquid and air mixing.

Implementation Method 1

whereby moving the second member in a withdrawal stroke from the retracted position to the extended position pressurizes the air chamber thereby forcing liquid and air through the foam generating member

Methodology Applied
Scientific EffectPressure gradient: Pressure Gradient

Implementation Method 2

a foam generating member for generating turbulence in air and fluid passing therethrough to produce foam

Methodology Applied
Scientific EffectTurbulence: Turbulence

Data Source

PatentEP2548487B1Withdrawal discharging piston pump
Publication Date: 2024.06.05 GOTOHTI COM INC
  • EP2548487B1 patent drawingFigure 1
  • EP2548487B1 patent drawingFigure 2
  • EP2548487B1 patent drawingFigure 3

AI summary

A pump assembly (10) with a first pump (40, 42) which draws liquid from a reservoir (60) and dispenses it to a second pump (42, 44). The second pump receives the discharge from the first pump and air such that the second pump discharges both liquid and air. The first pump preferably has a piston (14) movable in a first inner chamber and the second pump utilizes the same piston movable in a second outer chamber. Preferably, the second pump discharges in the withdrawal stroke, that is while moving from a retracted position to a withdrawn position.