Valve Stem Compression Control for Polyurethane Spray Can Filling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The deformation of valve components during the assembly and filling of polyurethane foam spray cans can lead to valve misalignment, reduced reaction speed, and increased risk of leakage or damage, affecting the efficiency and safety of the filling process.

Innovation Solution

Limiting the compression distance of the valve stem during propellant gas injection to no more than 85% of the compression distance corresponding to a reference point on the force-compression distance curve, as determined by testing, to maintain valve reaction speed and prevent deformation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the valve stem is compressed further to increase propellant gas injection speed, then the filling productivity is improved, but the valve components deform and reaction speed decreases

Engineering Contradiction:
Improvefilling speedVSAvoidvalve reaction speed
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent applies parameter changes by optimizing the compression distance parameter to 85% of the reference point. This parameter adjustment increases propellant gas injection speed while preventing valve component deformation, thereby maintaining valve reaction speed and resolving the contradiction between filling productivity and valve reliability.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the valve stem is compressed further to open the valve more, then the propellant gas injection efficiency is improved, but the valve components are damaged or misaligned

Engineering Contradiction:
Improveinjection efficiencyVSAvoidvalve alignment
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent changes the compression distance parameter to 85% of the reference point, which optimizes valve opening degree for efficient propellant gas injection while preventing excessive compression that would cause valve component damage or misalignment, thus maintaining manufacturing precision.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If the valve stem is compressed beyond the reference point to maximize gas flow, then the filling rate is improved, but the risk of propellant gas leakage increases

Engineering Contradiction:
Improvefilling rateVSAvoidleakage prevention
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent optimizes the compression distance parameter to 85% of the reference point, which maximizes propellant gas flow rate during filling while preventing valve component deformation that would cause sealing failures and leakage, thereby maintaining both filling rate and leakage prevention reliability.

Inventive Principle:
Principle #35Parameter changes

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 reduces the risk of valve damage and misalignment, ensures the valve maintains its reaction speed, and prevents propellant gas or liquid escape during the filling process, enhancing production efficiency and safety.

Implementation Method 1

the valve is opened by compressing the valve stem relative to the valve collar

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

pressurizing the closed container by injecting at least one propellant gas through the valve stem

Methodology Applied
Scientific EffectPressure increase: Pressure Increase

Data Source

PatentEP3898425B1Improved filling of propellant gas into polyurethane spray cans
Publication Date: 2023.06.21 SOUDAL
  • EP3898425B1 patent drawingFigure 1a~1b
  • EP3898425B1 patent drawingFigure 2~3
  • EP3898425B1 patent drawing

AI summary

A method is described for the production of a pressure container or spray can containing a composition for forming polyurethane foam, with the following steps: closing the container, after introducing the liquid components, by securing into the opening of the container head a valve (10) having a hollow valve stem (4) centrally arranged in a round valve cup (1) that extends into the valve collar (2), and pressurizing the closed container by injecting at least one propellant gas through the valve stem (4), whereby the valve is opened by compressing the valve stem (4) relative to the valve collar (2), towards the valve cup (1), characterized in that, during the injection, the valve stem (4) is compressed, from its resting position with the valve (10) closed, over a distance of at most 85% of the compression distance corresponding to the reference point (C) on the force-compression distance curve registered on a test bench for a valve (10) of the same embodiment.