Method and apparatus for producing bags from a woven-fabric tube

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sack manufacturing processes face issues with ribbon detachment at the opening ends of sacks, particularly in uncoated fabrics, leading to material loss and increased manufacturing costs due to manual handling and material waste.

Innovation Solution

Applying heat to the cutting line area of the fabric tube before closing the open end, using techniques like ultrasonic welding or hot contact welding, to bond the intersecting fabric ribbons and prevent detachment, while ensuring the fabric layers do not permanently connect.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the fabric tube is cut to length to produce tubular sack bodies, then the sacks can be formed and closed, but ribbon detachment occurs at the opening ends causing material loss and handling difficulties

Engineering Contradiction:
Improvesack production efficiencyVSAvoidribbon stability at cutting edges
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent applies heat treatment to the cutting line area of the fabric tube before closing the sack openings. This preliminary action prevents ribbon detachment by bonding the fabric ribbons at the cutting edges, eliminating the need for subsequent manual folding and connecting operations while maintaining ribbon stability throughout the production process

Inventive Principle:
Principle #10Preliminary action

2Reliability

If manual folding and connecting operations are performed to prevent ribbon detachment, then ribbon stability is improved, but manufacturing complexity and material loss increase

Engineering Contradiction:
Improveribbon stability at opening endsVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the manual mechanical process of folding and connecting ribbons with a thermal process. Heat is applied to the cutting line area to bond the fabric ribbons, substituting complex mechanical operations with a simpler thermal treatment that achieves the same ribbon stabilization goal while reducing process complexity

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

3Reliability

If manual folding and sewing operations are performed to create neat edges, then ribbon detachment is prevented, but material loss and manufacturing costs increase

Engineering Contradiction:
Improveedge integrity of sack openingsVSAvoidfabric material loss
Core Design Contradiction:
ReliabilityVSLoss of substance

Solution Approach 1:

The patent extracts the essential function of preventing ribbon detachment from the complex manual process of folding and sewing. By applying heat directly to the cutting line area, the solution isolates the critical bonding action to only where needed at the cutting edges, eliminating unnecessary material consumption associated with manual handling and creating neat edges

Inventive Principle:
Principle #2Taking out (Extraction)

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 method effectively prevents ribbon detachment, reducing material loss and manufacturing costs by automating the process and maintaining the integrity of the sack material, without requiring additional processing steps like manual turning or sewing.

Implementation Method 1

a cutting line area of the fabric on at least one open end of the tubular bag body is treated by heat application

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 2

using techniques like ultrasonic welding or hot contact welding

Methodology Applied
Scientific EffectUltrasonic welding: Ultrasonic Vibration

Implementation Method 3

using techniques like ultrasonic welding or hot contact welding

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP3126120B1Method and apparatus for producing bags from a woven-fabric tube
Publication Date: 2019.05.15 LOHIA CORP LTD
  • EP3126120B1 patent drawingFigure 1
  • EP3126120B1 patent drawingFigure 2~3

AI summary

In a method for producing bags from a woven-fabric tube (1), the flat woven-fabric tube (1) is fed from a tube-unwinding apparatus, or a tube-forming apparatus, to a cutting device, in which the woven-fabric tube (1) is cut to length along a cutting line (8) to give tubular bag bodies (7) which are open at both ends, wherein the operation of cutting the woven-fabric tube (1) to length takes place in a longitudinal-transportation section, in which the woven-fabric tube (1) and the tubular bag bodies (7) are transported in the longitudinal direction of the woven-fabric tube (1), wherein a cutting-line region (6) of the woven fabric at at least one open end of the tubular bag body (7) is heat-treated prior to this open end being closed.