Needle Hole Guide Control for Skip-Stitch Sewing Machines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In straight-stitch sewing machines, the sewing needle moving back and forth causes resistance on the thread between the needle hole and the to-be-sewn article, leading to sewing defects such as skipped stitches.
Innovation Solution
A sewing machine with a needle hole guide mechanism that includes a movable needle hole guide member, driven independently of the sewing needle's reciprocating motion, to support the to-be-sewn article and adjust its position vertically, and a control system to manage this movement, ensuring stable thread connection and reduced thread tension.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the sewing needle moves back and forth while holding the to-be-sewn article between the throat plate and presser foot member, then sewing operation can be performed, but resistance is exerted on the thread between the needle hole and the to-be-sewn article causing sewing defects
Solution Approach 1:
A thread guide member is introduced as an intermediary component between the needle hole and the to-be-sewn article. This thread guide member includes a thread guide hole that guides the thread from the needle hole to the article, reducing friction and resistance on the thread during needle reciprocation, thereby preventing sewing defects such as skipped stitches
Solution Approach 2:
The thread guide member is designed to be movable in the vertical direction, allowing it to dynamically adjust its position. The guide drive portion independently controls the vertical movement of the thread guide member, enabling it to adapt to different sewing conditions and maintain optimal thread guidance, thus reducing thread resistance and improving sewing reliability
2Reliability
If the needle hole guide member is made movable in the vertical direction independently of the sewing needle, then thread connection stability is improved, but device complexity increases
Solution Approach 1:
A guide drive portion is introduced as a control intermediary between the control system and the thread guide member. This guide drive portion specifically controls the vertical movement of the thread guide member independently from the needle reciprocation, allowing precise control of thread guidance while keeping the overall control architecture modular and manageable
Solution Approach 2:
The control system is segmented into distinct control portions: a lifting drive control portion for needle vertical movement, a belt drive control portion for presser foot movement, and a guide drive control portion for thread guide member movement. This segmentation allows independent control of each component, improving thread connection stability while maintaining clear separation of control functions to manage system complexity
Data Source
AI summary
A sewing machine that suppresses sewing defects is provided. The sewing machine includes: a sewing needle, held by a needle bar and moving back and forth while holding an upper thread; a shuttle, configured to hold a bobbin around which a lower thread is wound and which is housed in a bobbin case, and cooperating with the sewing needle to form a seam; a presser foot member, configured to press a to-be-sewn article at a sewing position directly below the sewing needle; a feeding mechanism, feeding the to-be-sewn article from the sewing position to a first direction; a needle drive portion, provided separately from a belt drive portion to synchronously move the sewing needle and the presser foot component in the first direction; and a control portion, which controls so that the needle drive portion and the belt drive portion operate independently.