Weft Thread Removal Device Pneumatic Mechanical Integration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing weft thread removal methods in weaving machines are inefficient, with pneumatic elements often unable to apply sufficient force and mechanical elements risking thread breakage due to high force and low speed.

Innovation Solution

A device combining a pneumatic unit for generating an air current downstream of a mechanical unit with clamping elements, allowing for both effective dust removal and rapid weft thread extraction by leveraging the suction effect and mechanical tensile force.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If pneumatic elements are used to remove weft threads, then the removal speed is improved, but the force applied is too small to remove weft threads that are caught or jammed in the shed

Engineering Contradiction:
Improveremoval speedVSAvoidtensile force on weft thread
Core Design Contradiction:
ProductivityVSForce

Solution Approach 1:

The patent combines a pneumatic element for rapid weft thread removal with a mechanical element for applying high tensile force. The pneumatic element includes a nozzle that blows air to propel the weft thread, while the mechanical element includes a finger that can clamp onto the weft thread to apply sufficient force to overcome jams and catches in the shed. This merging of pneumatic and mechanical systems resolves the contradiction by providing both speed and force.

Inventive Principle:
Principle #5Merging (Combining)

2Force

If mechanical elements are used to remove weft threads, then sufficient force can be applied to overcome jams and catches, but the removal speed is relatively low and the force may tear the weft threads

Engineering Contradiction:
Improvetensile force on weft threadVSAvoidremoval speed
Core Design Contradiction:
ForceVSProductivity

Solution Approach 1:

The patent combines a pneumatic element for rapid weft thread removal with a mechanical element for applying high tensile force. The pneumatic element includes a nozzle that blows air to propel the weft thread, while the mechanical element includes a finger that can clamp onto the weft thread to apply sufficient force to overcome jams and catches in the shed. This merging of pneumatic and mechanical systems resolves the contradiction by providing both speed and force.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The mechanical finger is designed with adjustable clamping force parameters to apply sufficient force to overcome jams without exceeding the threshold that would tear the weft thread. The system can dynamically adjust the force parameter based on the specific situation (normal removal vs. overcoming a jam).

Inventive Principle:
Principle #35Parameter changes

3Reliability

If mechanical elements apply high force to remove weft threads, then effective removal is achieved, but the weft threads risk being torn due to excessive force

Engineering Contradiction:
Improveeffective removalVSAvoidweft thread integrity
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The mechanical finger is designed with adjustable clamping force parameters to apply sufficient force to overcome jams without exceeding the threshold that would tear the weft thread. The system can dynamically adjust the force parameter based on the specific situation (normal removal vs. overcoming a jam).

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The mechanical element uses a spring-loaded finger that provides dynamic, adaptive force. The spring allows the finger to exert variable force - gentle force during normal operation and higher force when needed to overcome resistance, automatically adjusting to prevent thread damage while ensuring effective removal.

Inventive Principle:
Principle #15Dynamics

4Reliability

If a device combines both pneumatic and mechanical units for weft thread removal, then both speed and force are improved, but the device complexity increases

Engineering Contradiction:
Improveweft thread removal effectivenessVSAvoiddevice structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent integrates the pneumatic nozzle and mechanical finger into a single compact assembly where both elements work in coordination. The pneumatic element provides rapid propulsion while the mechanical element provides force multiplication, creating a synergistic system that achieves high reliability without excessive complexity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The combined device serves multiple functions: the pneumatic element handles normal rapid removal, while the mechanical element handles difficult cases requiring high force. This multi-functionality within a single integrated device resolves the complexity issue by providing versatile capability without requiring separate systems for different removal scenarios.

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

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

Enables reliable and rapid removal of weft threads, minimizing the risk of breakage while ensuring efficient dust clearance and high-force extraction.

Implementation Method 1

a first unit (9) for generating an air current through the device (1) according to the invention

Methodology Applied
Scientific EffectAir current flow: Convection

Implementation Method 2

a first unit (9) for generating a pneumatic tensile force on a weft thread

Methodology Applied
Scientific EffectPneumatic tensile force: Pressure Gradient

Implementation Method 3

a second unit (19) for generating a mechanical tensile force on a weft thread

Methodology Applied
Scientific EffectMechanical tensile force: Mechanical Force

Data Source

PatentEP3066243B1Device for removing weft thread
Publication Date: 2017.09.27 PICANOL NV
  • EP3066243B1 patent drawingFigure 1
  • EP3066243B1 patent drawingFigure 2~3
  • EP3066243B1 patent drawingFigure 4~6

AI summary

The invention relates to a device for removing weft thread, wherein the device (1) comprises a first unit (9) for generating a pneumatic tensile force on a weft thread (10, 11) and a second unit (19) for generating a mechanical tensile force on a weft thread (10, 11), wherein in the movement direction (A) of the weft thread the first unit (9) is arranged downstream of the second unit (19), so that weft thread (10, 11) which is guided through the device (1) by the air current generated by the first unit (9) can be clamped by the second unit (19), and wherein the device (1) comprises a housing (20) having a first bore (21), which in use extends in the movement direction (A) of the weft thread, and a second bore (22), which is disposed transversely to the first bore (21), wherein the second unit (19) is mounted in the area of the second bore (22).The invention also relates to a weaving machine having such a device.