Rotating Switch Plate Weft Gripper for Loom Selvedge Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing weaving technologies in gripper looms face challenges in eliminating the false selvedge system while maintaining mechanical simplicity, precision, and consistent weft tail cutting length, particularly when dealing with multiple wefts, as previous solutions either result in weft yarn loosening or mechanical complexity.
Innovation Solution
A weft yarn operating device with clamping grippers arranged on the outer circumference of a rotating switch plate, allowing for independent control and constant tension of weft yarns, combined with a comb-like yarn guide to prevent interference and maintain consistent path lengths, enables precise cutting and gripping without the need for a false selvedge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If clamping grippers are arranged close to the fabric edge to eliminate false selvedge, then material waste is reduced, but it becomes difficult to retain multiple waiting weft yarns without interference
Solution Approach 1:
The clamping grippers are arranged on the outer circumference of a rotating switch plate, transitioning from a linear arrangement to a circular/rotational dimension. This allows multiple grippers to be positioned along an arc, enabling them to retain multiple weft yarns simultaneously without interference while maintaining proximity to the fabric edge for material efficiency.
Solution Approach 2:
The switch plate is designed to rotate, bringing different clamping grippers into the work station position dynamically. This rotational mechanism allows the system to adaptively select and position the appropriate gripper for each weft yarn insertion, eliminating the need for static complex arrangements while reducing material waste.
2Device complexity
If multiple clamping grippers are arranged in series with common spring control, then device complexity is reduced, but independent control of each gripper is lost
Solution Approach 1:
Each clamping gripper is equipped with its own independent spring control mechanism, segmenting the control system from a common unified control. This allows each gripper to independently clamp and release its specific weft yarn, providing precise individual control while maintaining relatively simple overall device structure through modular design.
3Device complexity
If weft yarn path length varies during gripper movement, then mechanical simplicity is maintained, but weft yarn tension becomes inconsistent causing loosening
Solution Approach 1:
A comb-like yarn guide is positioned to maintain constant distance from the rotation axis, creating an equipotential path for the weft yarn. As the switch plate rotates and brings different grippers to the work station, the yarn guide ensures the weft yarn path length remains constant, maintaining consistent tension and preventing loosening while keeping the mechanical structure simple.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Weft yarn operating device, in a gripper loom, of the type comprising: respective clamping grippers (P) for each one of the waiting weft yarns (T), said clamping grippers (P) being mounted on a same and single support (S) which is arranged at the edge of the fabric being woven; a first motor means (Ms) which moves said support (S) in order to bring the clamping gripper (P) of a weft yarn to be inserted into the shed near a work station (L); a second motor means (Mp) which opens said clamping gripper (P) in opposition to retaining means which maintain the clamping gripper (P) in a closed position; and weft yarn directing means (6, 7) which, during the beating step, convey the weft yarn into said open clamping gripper (P). Support (S) is pivoted about a rotation axis (C) and said gripping grippers (P) are mounted on said support (S) along a circumference arc whose centre lies on said rotation axis (C). Yarn guide means are provided which are integral with said support (S) for passing all said weft yarns clamped by said gripping grippers (P) in a convergence area arranged in close proximity to said rotation axis (C) of support (S).