Segmented Rear Presser Foot for Automotive Seam Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current sewing technologies face challenges in controlling seam allowances, particularly in decorative stitches used in the automotive industry, where irregularities can prevent airbags from opening correctly and affect the aesthetic and comfort of garments, due to issues like color variations, material movement, and complex curves.
Innovation Solution
A device with a rear presser foot capable of independent vertical oscillation on both sides of the seam, equipped with sensors to detect material thickness and adjust accordingly, ensuring accurate stitch formation and preventing seam allowances from falling inward, thus maintaining the integrity of the airbag deployment zone.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If chromatic sensors are used to detect seam allowance opening, then the ability to distinguish right side and wrong side is improved, but the control of seam allowance position during sewing is insufficient
Solution Approach 1:
The presser foot is segmented into two independent pressurizing portions that can move vertically independently relative to the needle plate, allowing separate control of seam allowances on both sides of the stitching line
Solution Approach 2:
The pressurizing portions are designed to move vertically dynamically during sewing to adapt to varying fabric thickness and maintain proper seam allowance positioning, rather than using fixed pressure
2Ease of manufacture
If fixed presser foot pressure is used, then the sewing process is simple, but the seam allowance position cannot be controlled accurately on complex curves and varying thickness materials
Solution Approach 1:
The pressurizing portions move vertically in response to fabric thickness variations and curve complexity, providing adaptive pressure control that maintains accurate seam allowance positioning throughout the sewing process
Solution Approach 2:
The vertical position of the pressurizing portions is continuously adjusted during sewing to change the pressing parameters according to the specific requirements of different fabric sections, curves, and thickness variations
3Device complexity
If conventional single presser foot is used, then the device complexity is low, but differential control on both sides of the seam is not possible
Solution Approach 1:
The presser foot is divided into two independently controllable pressurizing portions, each capable of vertical movement relative to the needle plate, enabling separate control of seam allowances on opposite sides of the stitching line
Solution Approach 2:
The dual pressurizing portion presser foot serves multiple functions: it controls seam allowance positioning, adapts to varying fabric thickness, handles complex curves, and prevents material displacement, all within a single integrated component
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 solution ensures consistent seam quality, reduces defective products, and enhances safety by ensuring the airbag can deploy correctly, while also improving the aesthetic and comfort aspects of the garment by maintaining the intended seam structure.
Implementation Method 1
a sensor configured to detect the oscillation of the height of one of the forks of the rear presser foot
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The present disclosure describes a device and a method for controlling the quality of a textile seam for a sewing machine comprising: a rear presser foot with compensation comprising two forks for pressing the workpiece being sewn, a fork for each side of the seam after its passage through the needle seam area, wherein said forks are vertically and independently oscillating; a sensor configured to detect the height of a first fork; a signal processor configured to detect whether the height detected by the sensor when the first fork is pressing the workpiece is above a predetermined value of excessive thickness.