Rapier loom

A stationary package of yarn is used to supply the weft yarns in the rapier machine. One end of a rapier, a rod or steel tape, carries the weft yarn. The other end of the rapier is connected to the control system. The rapier moves across the width of the fabric, carrying the weft yarn across through the shed to the opposite side. The rapier is then retracted, leaving the new pick in place.

In some versions of the loom, two rapiers are used, each half the width of the fabric in size. One rapier carries the yarn to the centre of the shed, where the opposing rapier picks up the yarn and carries it the remainder of the way across the shed.[1] The double rapier is used more frequently than the single rapier due to its increased pick insertion speed and ability to weave wider widths of fabric.

The housing for the rapiers must take up as much space as the width of the machine. To overcome this problem, looms with flexible rapiers have been devised. The flexible rapier can be coiled as it is withdrawn, therefore requiring less storage space. If, however, the rapier is too stiff then it will not coil; If it is too flexible, it will buckle. Rigid and flexible rapier machines operate at speeds ranging from about 200 to 260 ppm, using up to 1300 meters of weft yarn every minute. They have a noise level similar to that of modern projectile looms. They can produce a wide variety of fabrics ranging from muslin to drapery and upholstery materials.

Newer rapier machines are built with two distinct weaving areas for two separate fabrics. On such machines, one rapier picks up the yarn from the center, between the two fabrics, and carries it across one weaving area; as it finishes laying that pick, the opposite end of the rapier picks up another yarn from the center, and the rapier moves in the other direction to lay a pick for the second weaving area, on the other half of the machine. The above figure shows the action on a single width of fabric for a single rigid rapier system, a double rigid rapier system, and a double flexible rapier system .

Rapier machines weave more rapidly than most shuttle machines but more slowly than most other projectile machines. An important advantage of rapier machines is their flexibility, which permits the laying of picks of different colors. They also weave yarns of any type of fiber and can weave fabrics up to 110 inches in width without modification.

See also

References

1. http://www.britannica.com/EBchecked/topic/491523/rapier-loom

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