DE1116921B - Method and device for testing fiber slats for a content of excessively long fibers - Google Patents

Description

IEITERNAT.I (L. GOln in the spinning of fiber slats, especially on clamping stretchers, in the interest of a smooth draft, the most uniform possible Stack desired. Particularly uncomfortable in this case are excessively long fibers that z. B. can occur with incorrect production of artificial fibers. In the direct production of fiber slats from endless thread bundles by means of offset Cutting or by tearing (so-called converter process or sliver tearing process) Particular attention must be paid to this possibility of error.

The usual methods of pile testing of fiber slabs where the rovings in a manner similar to the stretching process, e.g. B. in a clamping unit with adjustable draft distance, pulls apart and the occurring, in particular, it measures brief fluctuations in force on the delay line for testing fiber slats for a content of excessively long fibers is not sufficient.

Long fibers can be torn while processing the sample will. Above all, however, the procedures are very cumbersome and time-consuming and must be recorded nevertheless, only a very small sample amount at a time, so that the result is not certain says about the nature of the whole lot. This is especially true of the ones mentioned above shortened spinning processes, where no mixing of the parts takes place, but a possible stacking fault usually at a locally narrowly limited point of the Fuse occurs.

It has now been found that without any effort by hand Checked fiber quantities in Luntenforin for a content of overlong fibers and that The test result can be recorded in a registering manner if, according to the invention, the delay path is set shorter than it corresponds to the length of the extra-long fibers sought.

When using the method described, the sliver shape remains obtained so that the tested material can be used for spinning purposes.

It is even possible to "non-destructively" destroy entire batches before further use. to check, yes you can go into the production or further processing switch on the roving, for example by installing the device behind the sliver tearing machine or before the first spinning mill passage. Pulses can be given by the device and signaling or detaching devices are triggered. You can then after parking the faulty point - either for investigative purposes or to prevent harmful ones Effects in further processing - from the tape Method and device for testing fiber slats for a content of excessively long fibers Applicant: Farbenfabriken Bayer Aktiengesellschaft, Leverkusen-B ayerwerk Dr. Max-Otto Schürmann and Dr. Hans Haimerl, Dormagen, have been named as inventors 2 exceptions. By the way, can the device can run virtually unattended.

In order to avoid a slippage of the fibers on the rollers, there must be sufficient Clamping pressure applied; In addition, it is recommended to use the rollers with an elastic To cover the material with an adhesive surface (soft rubber).

A roller arrangement in the form of a so-called roller arrangement has proven particularly useful Jockey rollers, with a third roller on top of two lower driven rollers is wrapped in the tape, is loosely placed.

Two methods can be used for voltage measurement: a) Measurement the force required for the warping process, b) bending of the fiber bundle in the stretching field through a tactile organ.

The latter can either model with constant force with variable (Spring) acting tensile force. The deflection angle and / or the necessary one is measured Force.

The method described above under b) has proven particularly effective as a measuring method. A device used for this is shown schematically in Fig. 1.

The fuse 1 wraps around the driven rollers 2 and 3 from below, the loosely placed roller 4 from above. The voltage measurement takes place on the delay section 5. The sliver then revolves around rollers 6, 7 and 8 corresponding to the first group of rollers and is delivered at 9. The tactile lever 10 with the leich-109 7381177 3 th roller 11 is pressed by the spring 12 against the fiber bundle. The degree of Angling is indicated by the pointer 13. The damping 14 ensures the switch-off short-term vibrations.

Of course, the purely mechanical force measurement described here can be used also replaced by a mechanical-electrical (for example inductive) measurement will.

Fig. 2 shows a curve obtained with the device.

The increases in tensile stress in the stretching field, indicated by arrows indicate the faulty areas in the fuse.

Claims (6)

PATENT CLAIMS: 1. Method for testing fiber slats for a Content of excessively long fibers, in which the slivers in a clamping drafting system adjustable delay distance and the occurring, especially short-term Force fluctuations on the delay line are measured, characterized in that that the delay distance is set to be shorter than the length of the sought-after overlap Fibers. 2. The method according to claim 1, characterized in that the measurement the force fluctuations are made by measuring the tension in the warping area. 3. The method according to claims 1 and 2, characterized in that that the voltage measurement by preferably slight deflection of the fuse from the straight direction and measurement of force and / or deflection is made. 4 4. Device for performing the method according to the claims 1 to 3 with at least two driven in the same direction, from upper and Lower roller existing roller pairs, of which at least one pair is moved can be that the length of the stretching field in between can be changed, the rollers having a soft, elastic and adhesive surface Fabric, preferably rubber, are covered, characterized by a lever and spring pressure on the feeler that can be pressed on the fiber bundle in the stretching field, the position of the lever by a translation on a display or writing device is transferred. 5. Apparatus according to claim 4, characterized in that instead of of the roller pairs there are groups of three rollers each, two of which are horizontal stand one behind the other, while the third loosely laid out as a so-called jockey roller is. 6. Apparatus according to claim 4, characterized in that the pure mechanical force measurement by a mechanical-electrical, for example inductive Measurement is replaced. Considered publications: magazine »Textil-Praxis«, 1960, July, pp. 693 to 697; "Handbook of Materials Testing", E. Siebe, Vol. 5; "The Testing of textiles ", H. Sommer, 1960, pp. 464 to 469.