Upside-Down Container Cleaning With Split-Temperature Caustic Sprays

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cleaning methods for plastic and PET bottles are limited by the temperature sensitivity of the materials, which restricts the effectiveness of caustic cleaning and can lead to undesirable deformations such as shrinkage.

Innovation Solution

A method and device for cleaning upside-down containers that utilize a first lye at a higher temperature for the interior and a second lye at a lower temperature for the exterior, allowing for optimal cleaning without excessive heat input, using a device with separate nozzles and temperature control systems to manage the lyes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the temperature of the caustic is increased to improve cleaning performance, then the cleaning effectiveness is improved, but the plastic bottles undergo excessive shrinkage and deformation

Engineering Contradiction:
Improvecleaning effectivenessVSAvoidbottle shape stability
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The cleaning process is divided into two separate stages: a hot caustic spray stage (60-80°C) for interior cleaning and a cold caustic spray stage (20-40°C) for exterior cleaning. This segmentation allows each stage to operate at optimal temperatures without causing deformation, as the cold exterior spray prevents heat buildup that would cause shrinkage while the hot interior spray maintains cleaning effectiveness.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different temperature conditions are applied to different parts of the bottle: the interior receives hot caustic for effective cleaning, while the exterior receives cold caustic to prevent deformation. This local differentiation of temperature quality optimizes both cleaning performance and shape stability for respective surfaces.

Inventive Principle:
Principle #3Local quality

2Manufacturing precision

If the caustic temperature is limited to around 60°C to prevent bottle shrinkage, then the bottle integrity is maintained, but the cleaning performance is insufficient

Engineering Contradiction:
Improvebottle shape stabilityVSAvoidcleaning performance
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The cleaning process is divided into two separate stages: a hot caustic spray stage (60-80°C) for interior cleaning and a cold caustic spray stage (20-40°C) for exterior cleaning. This segmentation allows each stage to operate at optimal temperatures without causing deformation, as the cold exterior spray prevents heat buildup that would cause shrinkage while the hot interior spray maintains cleaning effectiveness.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different temperature conditions are applied to different parts of the bottle: the interior receives hot caustic for effective cleaning, while the exterior receives cold caustic to prevent deformation. This local differentiation of temperature quality optimizes both cleaning performance and shape stability for respective surfaces.

Inventive Principle:
Principle #3Local quality

3Strength

If cold water is sprayed only on the inside of glass bottles to prevent breaking, then the glass integrity is maintained, but the cleaning of the exterior is insufficient

Engineering Contradiction:
Improveglass integrityVSAvoidexterior cleaning effectiveness
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent inverts the conventional approach by spraying the interior with hot caustic and the exterior with cold caustic, rather than cooling only the interior. This inversion allows the exterior to be effectively cleaned with cold caustic while the hot interior spray maintains cleaning performance without causing thermal shock to the glass.

Inventive Principle:
Principle #13The other way round (Inversion)

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 method and device effectively remove interior and exterior contaminants while minimizing material deformation, achieving thorough cleaning without compromising the integrity of the containers.

Implementation Method 1

spraying the interior of an upside-down container with a first lye at a first temperature

Methodology Applied
Scientific EffectThermal energy: Heating

Implementation Method 2

spraying the interior of an upside-down container with a first lye

Methodology Applied
Scientific EffectChemical cleaning: Chemical Bonding

Implementation Method 3

exposing the exterior of the upside-down container to a second lye at a second temperature, the second temperature being at least 5°C lower than the first temperature

Methodology Applied
Scientific EffectThermal energy: Cooling

Implementation Method 4

exposing the exterior of the upside-down container to a second lye

Methodology Applied
Scientific EffectChemical cleaning: Chemical Bonding

Implementation Method 5

the second temperature being at least 5°C lower than the first temperature... minimizing material deformation

Methodology Applied
Scientific EffectThermal stress: Thermal Expansion

Data Source

PatentEP4194113B1Method and apparatus for cleaning head-mounted containers
Publication Date: 2025.09.24 KRONES AG
  • EP4194113B1 patent drawingFigure 1~2
  • EP4194113B1 patent drawingFigure 3

AI summary

The invention relates to a method for cleaning upside-down containers (2), for example, plastic containers, such as PET containers, comprising the steps of: spraying the interior (6) of an upside-down container with a first alkaline solution at a first temperature; and simultaneously applying a second alkaline solution at a second temperature to the exterior (7) of the upside-down container. The invention further relates to a device (1, 18) for cleaning upside-down containers, comprising a supply device with receiving positions for the upside-down containers; a spraying device (3) configured for spraying the interior of the upside-down containers with a first alkaline solution at a first temperature; and an application device (8) configured for simultaneously applying a second alkaline solution at a second temperature to the exterior of the upside-down containers.The second temperature is lower, for example at least 5 °C or 10 °C lower, than the first temperature.