Bag Layer Separation for Reliable Form-Fill-Seal Opening

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing filling devices for bags with unsealed upper ends face reliability issues in opening the bags due to strong adhesion between layers, leading to reduced output and performance in form-fill-seal machines.

Innovation Solution

A filling device with a layer movement device that uses suction devices and holding devices to move bag layers relative to each other, assisted by fluid flow and ionized fluid, to reduce adhesion and ensure reliable opening.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional opening elements are used to separate bag layers, then the bag opening process can be initiated, but the layers may adhere strongly causing opening failure and reduced reliability

Engineering Contradiction:
Improvebag opening reliabilityVSAvoidmachine output
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent replaces traditional mechanical opening elements with a pneumatic system. A suction device creates a pressure difference (vacuum) to engage and separate the bag layers, substituting mechanical force with pneumatic pressure differential. This resolves the adhesion problem by using negative pressure to pull layers apart rather than relying on mechanical piercing or tearing.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention employs a suction device that generates a vacuum to engage the bag layers and facilitate their separation. The pneumatic system creates a pressure difference between the inside and outside of the bag, allowing the layers to be pulled apart reliably without mechanical contact, thereby improving both opening reliability and maintaining productivity.

Inventive Principle:
Principle #29Pneumatics and hydraulics

2Reliability

If complete bag opening is performed in a dedicated station, then the bag can be fully opened for filling, but the overall FFS machine performance is reduced

Engineering Contradiction:
Improvebag opening completenessVSAvoidFFS machine performance
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent combines the bag opening function with the transport function by integrating the suction device into the transport mechanism. The same pneumatic system that transports the bag also performs the opening operation, eliminating the need for a separate opening station and maintaining high machine performance while ensuring complete bag opening.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The suction device serves multiple functions: it transports the bag, opens the bag layers, and prepares the bag for filling. This multi-functional approach eliminates dedicated opening stations, reduces machine complexity, and maintains high productivity while ensuring reliable and complete bag opening.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Ease of operation

If suction cups are used to open the bag wide, then the bag can be easily opened, but the suction cups may detach from the bag walls causing transport failure

Engineering Contradiction:
Improvebag opening easeVSAvoidtransport reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The suction device applies partial opening action rather than completely wide opening. It creates just enough separation between the layers to facilitate filling while maintaining sufficient suction contact with the bag walls. This partial action prevents over-opening that would cause suction cup detachment, thereby maintaining transport reliability while still achieving effective bag opening.

Inventive Principle:
Principle #16Partial or excessive action

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 device achieves reliable opening of bags with reduced mechanical effort, enhancing the efficiency and reliability of the form-fill-seal process by minimizing layer adhesion and ensuring effective filling.

Implementation Method 1

the layer movement device comprises at least one suction device with which at least one layer of the bag can be engaged on the outside

Methodology Applied
Scientific EffectSuction: Suction

Implementation Method 2

assisted by fluid flow and ionized fluid

Methodology Applied
Scientific EffectFluid flow: Fluid Spray

Implementation Method 3

assisted by fluid flow and ionized fluid

Methodology Applied
Scientific EffectIonization: Ionisation

Data Source

PatentEP3755631B1Filling device and method for filling bags with a respective unsealed upper end
Publication Date: 2025.11.26 WINDMOELLER & HOELSCHER GMBH
  • EP3755631B1 patent drawingFigure 1
  • EP3755631B1 patent drawingFigure 2
  • EP3755631B1 patent drawingFigure 3~4

AI summary

The invention relates to a filling device for filling bags with a respective unsealed upper end and at least two layers lying on top of one another. A filling station for filling the bags is characterised in that the filling device comprises at least one layer movement device (30) for moving the at least one layer of the bag relative to the at least one second layer, with which the layers of the bag can be acted upon, wherein the layer movement device is arranged in front of the filling station.