Knitted Wire Yarn with Inclined Arcuate Loops
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods of manufacturing yarns for gland packings result in filler materials slipping off due to large stitch gaps, leading to increased manufacturing costs when stitches are minimized to prevent slipping.
Innovation Solution
A method involving knitting wire material with concentrically placed needles that revolve around a rotation axis, forming inclined arcuate loops to create uniform, smaller stitches that securely enclose filler materials within a tubular shape, reducing slipping while maintaining low manufacturing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the stitches are made as small as possible to prevent filler material slipping, then the reliability of filler material retention is improved, but the manufacturing cost increases due to excessive wire material usage
Solution Approach 1:
The patent changes the geometric parameters of the stitches by forming arcuate loops with specific curvature radii (R1 and R2) that are different from each other. This parameter change allows the stitches to provide better retention of filler materials through their curved geometry, reducing slipping while maintaining reasonable wire material usage and manufacturing cost.
Solution Approach 2:
The patent applies asymmetry by creating stitches with unequal curvature radii on opposite sides (R1 ≠ R2). This asymmetric stitch configuration provides differential engagement with the filler materials, improving retention effectiveness without requiring uniformly small stitches throughout, thereby balancing reliability with manufacturing cost.
2Device complexity
If the number of knitting needles is reduced to simplify the structure, then the device complexity is reduced, but the manufacturing precision of stitch uniformity deteriorates
Solution Approach 1:
The patent applies local quality by assigning different curvature radii (R1 and R2) to different locations within the same stitch structure. This allows each part of the stitch to have optimized local geometry for filler material retention, achieving high manufacturing precision in stitch functionality without requiring a large number of knitting needles to create uniformity through quantity.
Data Source
AI summary
In order to manufacture a yarn in which filler materials are loaded into a tubular member, the method of manufacturing a yarn has a step of knitting a wire material to form the tubular member. In the step of knitting the wire material, knitting of the wire material is advanced by a plurality of knitting needles, which are placed substantially concentrically about a rotation axis, while revolvingly moving the knitting needles about the rotation axis. When a stitch is to be formed by the wire material, the wire material is prepared so that an arcuate loop portion, which defines a part of the external shape of the stitch, is expanded in a direction which, in a state where the tubular member is developed, is inclined with respect to a straight line that extends in the axial direction of the tubular member.