A
t the ITM 2004 International Exhibition of Textile Machinery,  held recently in
Turkey, Schlafhorst, a subsidiary of Germany-based Saurer GmbH & Co. KG, highlighted its
Autoconer 338 yarn winder. According to Schlafhorst, the Autoconer 338 is highly popular in the
Turkish market, with several thousand units already installed.

With the Autoconer 338 product family, the textile industry has a technology that is capable
of efficiently winding yarn for any application, according to the company. The winder’s modular
platform makes automatic yarn package winding economically efficient. Additional performance
features – which include advanced monitoring and operating systems, and intelligent closed-loop
control systems – ensure package quality and efficiency.

One System, Many Package Formats


The Autoconer 338 produces yarn packages in various formats to meet the diverse production
requirements downstream of winding. Conical and tapered packages with a 3-inch to 6-inch yarn-guide
traverse are wound tightly with large diameters for warping and weaving, loosely for package
dyeing, or waxed with increasing taper for knitting.

With the Autotense FX and Propack FX modules, the Autoconer 338 has two control systems to
optimize yarn tension and contact pressure, which affect the internal structure (yarn laying) and
density – criteria for measuring package quality. Schlafhorst says both the Autotense FX and
Propack FX systems are characterized by continuous, accurate measurement; and direct, precise
control – producing packages that are uniform in build, density, diameter and format. Symmetrical
and asymmetrical drum types with different numbers of groove turns are available, ensuring precise
yarn displacement that matches the material to be processed.

In cases where power supply is unreliable, the Quality Cut power-failure circuit prevents
the occurrence of run-out patterns by lifting and braking the package separately. When processing
elastic materials such as elastic core yarns and Siro-spun wool yarns, the characteristic
bulging-out of yarn on the package flanks can be minimized using Schlafhorst’s integrated Variopack
FX system.

Process-Oriented Packaging


Each production process makes particular demands on the yarn package. The Autoconer 338
permits the winding operator to tailor package formats to the requirements of downstream processes.

Packages can be produced with large diameters and optimal unwinding properties for warping
and weaving applications. For example, the Propack FX system can help avoid the diameter
limitations that result from critical pattern zones. Highly precise length measurement guarantees a
uniform package run-out in warping, thus reducing waste considerably.

For knitting packages, the constant yarn tension generated by the Autotense FX forms the
basis for an even level of waxing. Specific yarn tension settings ensure a constant low-wax
application, which is operational in the optimum range of the waxing curve. An optional
wax-monitoring system issues early warnings before the wax roll runs out and guarantees that no
unwaxed yarn will run onto the package.

The identical package diameter and yarn tension of the Autoconer 338 packages, along with
their precisely measured running lengths, are key to producing high-quality plied yarns. These
packages can be used directly for twisting or assembly winding.

When winding dye packages, the Propack FX, Autotense FX and central setting of the winding
parameters allow for low, uniform package densities to be reproduced repeatedly. In addition, the
Autoconer 338 can produce dye packages with particular densities by centrally adjusting the yarn
tension on the Informator, yielding packages that give consistent, reproducible dyeing results. In
certain cases, the optimum package build makes it possible to use dyed packages directly in warping
and weaving without rewinding.

Gentle Yarn Handling

And Safe, Reliable Winding


High process reliability and package quality are ensured by the coordination of process
sequence functions and the optimal arrangement in the yarn path of various parts, including winding
unit control, yarn-guide-drum direct drive, package soft start-up, standard electronic
anti-patterning, and package lift-off after a clearer cut or yarn break.

The results are gentle yarn handling and a safe, controlled production process.

Schlafhorst uses  state-of-the-art sensor technology to monitor the winding process,
which results in intelligent regulation, short piecing cycles and the elimination of unnecessary
additional cycles.

The unique upper yarn sensor and vacuum-controlled suction system create a package built
with gentle yarn handling. The low vacuum level can be set specifically for the yarn, and together
with short search and suction times in the area of the upper yarn, this guarantees gentle handling
of the package surface. Roughening of the surface caused by intense suction is avoided by the
lifting of the package each time there is a yarn break or clearer cut, as the drum and package are
braked separately.

Meanwhile, the upper yarn sensor plays an essential role in reducing waste. During the
splicing cycle, defects are pulled off the package, and the upper yarn sensor recognizes the
presence of the yarn end immediately. After a yarn break or bobbin change, the splicing cycle at
the winding unit continues as soon as the presence of the yarn is established, ensuring that only
the necessary length of yarn is unwound from the package.

August 2004