Apparatus for drafting systems loading control of ring frames.

Hanganu, Lucian Constantin ; Grigoras, Stefan ; Stirbu, Cristel 等

1. INTRODUCTION

The ring spinning will continue to be the most widely used form of spinning machine in the near future, because it exhibits significant advantages in comparison with the new spinning processes. Following are the advantages of ring spinning frame:

* it is universally applicable, i.e. any material can be spun to any required count;

* it delivers a material with optimum features, especially with regard to structure and strength;

* it is simple and easy to master;

* the know-how is well established and accessible for everyone.

A general schema of a ring frame is presented in figure 1 (Hanganu, 2004; Visileanu, E. et al., 2008) and one of its main functions is to draft the roving until the required fineness is achieved. In fact the drafting arrangement DF--figure 1, is the most important part of the machine. It influences mainly evenness and strength. The following points are therefore very important: drafting type, design of drafting system, drafting settings, selection of drafting elements, choice of appropriate draft, service and maintenance. In figures 2 is presented the same general structure of a drafting system corresponding for its main three working moments: open weighting arm (I), non- armed weighting arm (II) and armed weighting arm (III).

[FIGURE 1 OMITTED]

Between the top rollers 1 of the weighting arm WA and the bottom rollers 2 of the ring frame is passing the fibers structure to be transformed from rover in yarn (Hanganu, 2007).

[FIGURE 2 OMITTED]

2. CONSTRUCTIVE SOLUTION

The loading control apparatus of technological forces specific for drafting systems of ring frames is constructed from two distinct devices: a mechanical subassembly and an electronic structure--figure 3:

--the mechanical device (M) is designed so that it can be adapted for all types of drafting systems from ring frames and it represents the basic support for strain gauges transducer.

--the electronic structure (E) is dedicated both for signal processing produced by the mechanical device transducer and for displaying the values for technological loads too.

[FIGURE 3 OMITTED]

The mechanical device is able to reproduce the pressure cylinders (top rollers) of weighting arms as is shown in figure 4 with the possibility of adjusting the characteristic dimensions R, r, L, l.

On the measuring bar 1 are applied directly opposite two strain gauges 2 with their plans direction perpendicular to the pressing force F--figure 5; these strain gauges are protected with the help of a bushing 3. To obtain different values of the distance L between the two rollers as is required from various constructive types of drafting systems, there were designed two identical adjustment subassemblies--figure 6, which are able to move through corresponding guides 4 executed on the measuring bar 1--figure 4.

[FIGURE 4 OMITTED]

[FIGURE 5 OMITTED]

The radius R adjustment of each top roller, as the main component of the weighting arm, is made with the help of the graduated drum 5 which has the possibility to be misplaced in relation with the frame 6 helped by the screw 7 and the nut 8. This adjustment is obtained under the micrometer principle. To lock the device in the adjustment position it is necessary to action on the wheel 9 acting the rod 10. Adjustments to the radius r and the dimension l are made by replacing the dismountable bushes 3 specific for each controlled type of drafting systems. The L dimension is obtained by misplacing on the measurement bar of the two adjustment subassemblies dedicated for the radius R. The entire mechanical device is settled on the bottom roller of drafting system helped by the bed plates 14 which have the possibility of self-centered due to the cutters 12.

The detailed elements as components of an adjustment subassembly are presented in figure 6. There are used the next notations: 1--lock rosette; 2--nut; 3--special washer; 4--nut; 5--screw; 6--frame; 7--graduated drum; 8--ring; 9--locking rod; 10--slide; 11--bara support bar; 12--adjustment screw; 13--special rivet; 14--bed plates.

[FIGURE 6 OMITTED]

The electronic device receives the signal from strain gauges through a flexible shielded cable and is schematically represented in figure 7.

[FIGURE 7 OMITTED]

In figure 8 it is presented a practical application of this apparatus concerning the loading control of drafting system from a flax and hemp spinning ring frame machinery.

[FIGURE 8 OMITTED]

3. CONCLUSIONS

The entire apparatus is designed to be portable and power supplied with 6 V DC. It can measure loadings as technological forces specific for weighting arms with values up to 1000 N with a sensitivity of [+ or -] 0.5 N and it is provided with signalization circuit for failures such as supply voltage decreases and discontinuation of transducers conductors.

The method based on this apparatus constructive solution presented in this work permit to undertake the loadings measurement with high precision in very short time.

It also offers performance settings required when such situations are strictly necessary to be solved.

4. REFERENCES

Hanganu, L. C. (2007). Spinning Machine Design (in Romanian), Junimea Publishing House, ISBN 978-973-37-1222-0, Iasi, Romania

Hanganu, L. C., Vilcu, M. & Harghel, L. (2004). Spinning Ring Frames, Tehnopress Publishing House, ISBN 973-8377-89-7, Iasi, Romania

Visileanu, E. et al. (2008). INCDTP--Active Partner of the RDI National Network. Part IV, Industria Textila, Vol. 59, No. 1, February 2008, p. 3-13, ISSN 1222-5347

*** (2008) Final Report for Romanian Excellence Resarch Project No. 205, with AMCSIT-POLITEHNICA Bucharest

*** (2007). Technical Book for Weighting Arms and Top Rollers, Accotex-TEXParts GmbH, Germany

*** (2009). Suessen Ring Spinning--Technical Book, Spindelfabrik Suessen GmbH, Germany