外文翻译

Weaving Machinery

The shuttle looms have a wide degree and fall into three main classes:

Hand looms

Still used in relatively large quantities for product of all types of fabrics in the less developed countries ,but also used in some developed countries for the production of certain classic brocade ,tapestries and tweeds.

Non-automatic power looms

These machines are being used in ever decreasing numbers, especially in the developed countries ,but they seem likely to retain a certain usefulness in the production of special ist fabrics, such as industrial fabrics woven from heavy wefts.

Conventional automatic looms

Machines that have gained worldwide popularity because their advantage of versatility and relatively cheapness.

The inherent problems of pirn-winding of shuttle looms and the dynamic problems created by the picking and checking mechanisms in these looms have encouraged loom makers to investigate and develop various alternative means of weft insertion:

(1)Single or multiple gripper or projectile looms .

(2)Rapier looms.

(3)Water jet looms and air jet looms.

Of the many various types projectile looms developed ,the multiple projectile Sulzer weaving machines was the first ,and to date it is the only looms of its type to become widely established .Initially ,it was suitable for only a limited ranged of relatively plain fabrics ,produced from spun yarns .Over the years ,it has been developed to weave dobby ,Jacquard and terry fabrics with up to 8 different colors weft.

Rapier looms are made in a variety of types .The rapier looms may be required to extend across the full width of warp ,in which case they will be of a rigid construction ,or alternatively 2 rapiers may enter the shed from opposite sides the loom and transfer the weft from one rapier head to the other at a point near the center of the loom ,In the later case ,the rapiers may be either rigid or flexible .The future of this method of weft insertion would appear to lie mainly in the field of multi-color work ,since their rates of insertion are generally only comparable with those of conventional automatic looms .It should also be remembered that only 50% of the rapier movement is utilized in weft insertion ,and , for single rapier looms ,this wasted movement is also a time loss.

The technique of inserting weft in a fluid jet achieves weft-insertion rates comparable with those achieved by the Sulzer weaving machines , but there are width limitations .Water jet looms have been shown to be the most economical for producing certain types of plain continuous filament fabric especially when they are produced from hydrophobic synthetic fiber fabrics. Loom designers have constantly sought to replace the shuttle as a means of filling insertion .The prime reason is the rate of production . Physical laws dictate that ,to move through the shed ,the shuttle must be accelerated and decelerated .This naturally takes time and energy . If less time could be spent accelerating the shuttle ,and the transit time of the shuttle through the shed could be reduced ,higher loom speeds could be obtained .Secondly ,with the removal of the filling supply package from the filling carrier ,the filling carrier could be made smaller so the yarn movement in