Notched Fastener Stock Linear Feed Mechanism
Solution Overview
Problem
Conventional fastener dispensing systems using rotary feed wheels result in inconsistencies in cutting location and size due to the elasticity of fastener filaments, leading to improper retention and increased complexity and cost.
Innovation Solution
A fastener stock with longitudinal side members and equidistantly spaced cross-pieces, featuring rectangular or square engagement notches, is used with a linearly moving feed mechanism to ensure consistent cutting and insertion, replacing the rotary wheel with less flexible side members and notches that guide the cutting process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a rotary feed wheel is used to engage and pull the fastener stock, then the fastener stock can be fed to the needle assembly, but the elasticity of the filaments causes variation in cut location and reduced manufacturing precision
Solution Approach 1:
The fastener stock is segmented into discrete fasteners separated by notches, with each notch providing a defined engagement point for the feed mechanism. This segmentation eliminates the elasticity problem by creating rigid, discrete engagement points rather than continuous flexible filaments.
Solution Approach 2:
The notches are pre-formed in the fastener stock at precise intervals during manufacturing. This preliminary action establishes the exact cut locations and feed positions before the fastening operation, ensuring consistent spacing and eliminating variation caused by filament elasticity during feeding.
2Ease of operation
If a rotary feed wheel system is used, then fastener feeding is achieved, but the system complexity and operational cost increase
Solution Approach 1:
The feed mechanism extracts only the essential function of engaging and advancing the fastener stock without the complex rotary wheel assembly. The notched structure allows for a simplified linear feed mechanism that engages notches directly, eliminating the need for rotary motion and associated complexity.
Solution Approach 2:
Instead of using a complex rotary mechanism to create engagement points, the invention inverts the approach by pre-forming engagement notches in the fastener stock itself. This allows a simpler feed mechanism to engage the pre-prepared notches, reversing the traditional approach of creating engagement points through complex feeding motion.
Data Source
AI summary
An improved fastener stock comprised of a pair of longitudinal and continuous side members which are coupled to a plurality of equidistantly spaced cross-pieces. The pair of longitudinal and continuous side members are extended in a parallel spaced relationship, and the series of cross-pieces are arranged at spaced intervals between the side members so as to connect the side members. Along at least one of the side members, a series of engagement notches are present at spaced intervals between each of the cross-pieces members, and the engagement notches are rectangular or square in shape. A method of applying a fastener to an article is provided. The method includes initially feeding substantially continuous fastener stock from a supply, engaging at least one engagement notch, urging the fastener stock forward, feeding the fastener stock to a needle assembly, cutting a fastener from the fastener stock, and inserting the fastener into an article.