The weft accumulator is a machine used to wind threads. It has two main parts, a prewinder drum and a threading tube. The prewinder drum releases a thread reserve on the accumulator, and the threading tube leads the thread back to the end of the weft thread connected to the yarn package. This alternate thread is then attached to a second yarn package and is ready for joining at a predetermined location.
The weft accumulator is a crucial part of the weaving process, minimizing the tension variations during yarn insertion. It is a fundamental machine, but it can be enhanced with special accessories. Here are some of them. When properly used, a weft accumulator can help create the perfect fabric.
The first part of a weft accumulator is a tube with perforations at regular intervals. The perforations form an angle to the tube's radius 15 in a particular direction. The second part of the weft accumulator comprises an air injector that has spiral grooves. These grooves impart vortex motion to the airstream, forcing the weft thread 11 to coil.
A weft accumulator increases the efficiency of the weaving process and decreases downtime. The system has been proven in trials conducted at the University of Aachen's Composites Division. In one study, the weft accumulator improved the coverage ratio, and the tensile strength of fabric in the weft direction.
A weft accumulator limits the length of yarn coils according to the weaving width. It also limits the time that the needle takes to lift and lower the yarn coils. It is important to periodically clean the accumulator and maintain the efficiency of the jet loom. In addition, regular maintenance will ensure smooth operation and minimize failure rates.
A weft accumulator can also help increase the speed of the weaving process. A high-speed weft accumulator has the capacity to increase the speed of the weft yarn by up to 2,400 m/min. However, too high a speed will result in the weft yarn slipping onto the drum surface, causing it to overlap with subsequent weft coils.
The drums can be cylindrical or conical. A cylindrical drum pushes the yarn forward on its surface. The squeezing force is maximized when there is an angle of 135 degrees between the drum surface and the cone surface. This angle is mostly used in a dynamic drum weft accumulator. A conical drum decreases the diameter of the yarn coil as it moves forward, and decreases the tension in the weft.
There are two main types of weft accumulators. One type is a fixed drum that can store up to 2 meters of weft yarn.
