Application of Double-Sheet Detection Sensors on Fully Automatic Warp Threading Machines - Atonm

Abstract

Warp threading before weaving is an essential step for every textile factory. With technological progress, more factories use automatic threading machines instead of manual threading. This article briefly describes the basic structure of automatic threading machines, the application and development of Staubli and domestic threading machines, and proposes a solution to the problem of double-sheet overlap on stop-picks.

As is well known, after sizing, warp yarns must pass through the heddles and reed and then be placed on stop-picks before feeding into the machine. For new yarn types, the warp must be threaded through heddles and reed according to the process requirements before weaving; this preparation influences the efficiency and weaving quality of automatic shuttleless looms such as air-jet and rapier looms. Manual threading requires workers with weaving expertise, is time-consuming and inefficient, and fewer young workers choose this job. Therefore, more textile factories adopt machines rather than manual labor.

Basic structure of an automatic threading machine

Threading preparation is the pre-weaving setup defined by machine process requirements. Since the 1950s, the industry progressively developed classic machines. The basic structure of modern threading machines is illustrated above.

(Threading machine structure)

In 1991 Zellweger introduced the Delta series. The Delta 200 threading machine is divided into a creel carrier and a head. The creel connects to the creel carrier and places the yarns onto the rack. The head includes four function modules: yarn module, combed wire module, spring module and stop-pick module.

Automatic threading machines integrate computer control, optical imaging, pneumatics, stepper and servo motor control, and fiber-optic communication. Their disadvantages include many wear parts—especially with synthetic fibers—short service life, high maintenance requirements and higher cost, so component durability must be improved.

 In practice, fully automatic threading machines can occasionally feed double stop-picks due to mechanical issues.

The ultra-compact M8 probe of the Atonm Metal Double-Sheet Detector can reliably detect overlaps of very narrow metal sheets and is an ideal solution for detecting overlapping stop-picks in textile machines.