Sewing Thread End Removal via Upper Thread Tensioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for sewing large-area material layers using double lockstitch machines are inefficient due to time-consuming material layer changes and manual handling of thread ends, which can damage the material.
Innovation Solution
The method involves tensioning the upper thread to pull the lower thread end onto a surface, allowing for automatic cutting of thread ends, reducing manual intervention and minimizing material damage by ensuring thread ends appear on only one surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If manual removal of thread ends is performed, then thread ends can be removed from both surfaces, but the process is time-consuming and can damage the material
Solution Approach 1:
The invention extracts the lower thread end from the interior of the sewing material to the exterior surface by tensioning the upper thread. This allows the lower thread end to be accessed and removed from only one surface (the needle-facing surface), eliminating the need for manual intervention on both surfaces and reducing material damage risk.
Solution Approach 2:
The upper thread serves a dual function: it not only performs the sewing function but also automatically pulls the lower thread end to the surface through tensioning during material transport. This self-service mechanism eliminates the need for separate manual thread end removal operations.
2Ease of operation
If thread ends are cut off manually from both surfaces, then complete thread removal is achieved, but the process requires significant time and labor
Solution Approach 1:
By extracting the lower thread end to the exterior surface through upper thread tensioning, the invention makes the thread end accessible for automated cutting from only one surface, significantly reducing the operational effort and time required compared to manual removal from both surfaces.
Solution Approach 2:
The invention replaces the manual mechanical process of removing thread ends from both surfaces with an automated system where the upper thread mechanically pulls the lower thread end to the surface, enabling automated cutting and reducing both labor and time.
3Productivity
If the upper thread is tensioned to pull the lower thread end to the surface, then thread end removal is simplified, but excessive tension may tear the thread or material
Solution Approach 1:
The invention applies dynamic tensioning where the upper thread is tensioned progressively during material transport rather than applying maximum tension immediately. This dynamic approach allows the lower thread end to be gradually pulled to the surface without exceeding the tensile strength of the threads or material, maintaining reliability while achieving productivity gains.
Solution Approach 2:
The invention changes the tension parameter from a static high-tension state to a dynamic, controlled tension state that increases gradually during material transport. This parameter change ensures that the lower thread end is pulled to the surface efficiently while preventing thread or material damage through excessive force.
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 significantly reduces the effort required for thread end removal, protects the sewing material from damage, and enables precise control over tension to avoid thread tearing, resulting in a more efficient and reliable sewing process.
Implementation Method 1
the upper thread is tensioned in such a way that the lower thread connected to the upper thread is pulled with its end facing the sewing material up to above a surface facing the needle
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The method involves penetrating a needle (70) with an upper thread (66) in a sewing item (72), and connecting the upper thread with a lower thread (68). The needle is withdrawn from the sewing item. The upper thread is tightened in such a manner that the lower thread connected with the upper thread is drawn with an end, which is turned towards the sewing item, above a surface (76) turned above the needle, so that an end (78) of the lower thread is removed at a region of the surface. The lower thread is sectioned before clamping the upper thread at an end of a sewing section.