The JL 59/1 B Jacquardtronic Lace machine illustrates that versatility and speed do not necessarily have to be mutually exclusive.This all-round machine is based on the same concept as the JL 42/1,whose speed has been increased so that it now operates at speeds of up to 850 min-1–an increase of 40%compared to similar jacquard raschel machines having a conventional design.
The machine was equipped with the Positive Patternbeam Drive(PPD)to enable the speed potential of the innovative Jacquardtronic Lace machine to be fully exploited when operating from pattern beams.This high-performance drive system also enables yarns to be fed from pattern beams at high speeds of 850 min-1–with all the associated advantages that this offers.
The PPD system ensures that the yarns are delivered at the constant required tension level,based on the principles of inputting the feed data at the machine's computer and by making adjustments,which are initiated by the yarn tension controllers.
This overcomes the restrictions that high speeds have placed on delivering yarns from pattern beams so far.Until now,it has not been possible to guarantee controlled yarn feed at speeds of 600 min-1 and above.Because looping and distortion occurred,it was preferable to deliver the yarn from a creel.
The PPD system now enables high-quality lace to be produced extremely efficiently by exploiting the possibilities of being able to control the fabric-specific speed of the pattern beams.
The advantages of using pattern beams
Replacing yarn feed from creels with delivering yarns from pattern beams has led to a large number of advantages.These include lower space requirements,resulting in shorter yarn paths,simple,fast changeover procedures-which is an advantage when developing patterns and processing smaller batches-lower capital outlay and minimal storage.
Compared to using the conventional,passive drive system,PPD also offers advantages for the pattern beam.In addition to maintaining a constant yarn tension and supplying the exact amount of yarn required,another advantage is the increased efficiency,since balancing is no longer necessary.
The adjustments that used to have to be carried out in order to iron out any irregularities cost time and manpower,resulted in machine stoppages,and ran the risk of reducing the quality.
What is more,the PPD also enables the maximum running length of the pattern beams to be increased,which reduces machine downtimes.It is now possible to produce wound diameters of up to 13.5 cm–a size that increases the running time by about 50%with maximum warp lengths.
Same quality,better performance–the PPD makes it possible
The JL 59/1 B has proved its performance capabilities when working a lace design created by KARL MAYER.To test the performance of the machine,the pattern was produced using a creel first of all,and then processed from pattern beams.In order to do this,the Jacquardtronic Lace machine was equipped with six pattern beam mounting rails,which each carried eight pattern beams.
The JL 59/1 B operated with yarn feed from the creel as well as from the pattern beam at a speed of 850 min-1 in both cases to produce a lace of perfect quality.No differences could be detected either in the fabric construction or the appearance.If the use of PPD is compared to using weight-braked pattern beams,the advantages in terms of efficiency are plain to see.
At a threshold speed of 600 min-1,18.9 metres of lace were produced per hour,whereas the production rate of the Jacquardtronic Lace was 26.8 m/h during the performance tests–these figures are just as impressive as the appearance of the fabric.
