CENTRIFUGAL HYDROEXTRACTOR FOR REMOVABLE BOBBIN-HOLDER SHAFTS

The present invention relates to a centrifugal hy- droextractor for removable bobbin-holder shafts which can be used in dyeing systems of yarns on bobbins .

For dyeing systems of yarns on bobbins, the ever- rapid changing of fashion not only requires greater operative flexibility but also inevitably causes a reduction in the weights of the single batches to be treated and consequently a reduction in the productivity of the equipment available and daily production.

For this reason and due to the continuous increase in the costs of dyes and auxiliary products, labour and above all, energy sources, the field has the ever- increasing necessity of plants which contribute to reducing the production costs.

These demands are fully satisfied by the dyeing equipment illustrated in patents EP 1,390,574 Bl and EP 1,390,575 Bl, filed by the same Applicant, which, in spite of their constructive differences, are similar not only in that they operate with a reduced dye bath ratio, but mainly in the fact that they do not use the common so-called "candelabrum" bobbin-holders, substituted by removable and extractable bobbin-holder shafts. These re- movable and extractable bobbin-holder shafts are posi-

tioned on a single circumference and consequently, in order to complete the operating cycle, they can be inserted directly in a centrifugal hydroextractor and in the subsequent dryer, without onerous intermediate maneuvers. A limiting factor for this type of dyeing equipment, however, which, together with the centrifugal hydroextractor and dryer, which can be of a different model, form a complete dyeing system, is that this dyeing system has to be based on constructive modularity, i.e. on the use of machines with the arrangement of the bobbin-holder shafts on a circumference which is always identical.

This consequently assumes the initial selection of the basic capacity of the single apparatus, whose circumference, on which the bobbin-holder shafts are posi- tioned, inevitably determines the dimensions of the hydroextractor, which is common to various types of dyeing equipment. For varying their production capacity, the dyeing apparatuses must consequently be coupled or combined with each other, always maintaining, however, the initial modularity.

Once the basic capacity has been selected, of 100 Kg of yarn, for example, it is possible to operate with a single apparatus of 100 Kg, with two 100 Kg apparatuses coupled or combined with each other and therefore with 200 Kg of yarn, with three 100 Kg apparatuses coupled or

combined with each other and therefore with 300 Kg of yarn, or also with more than three apparatuses and so forth, depending on the constructive combination of the apparatuses themselves, still however maintaining the modularity of the basic capacity of 100 Kg to be treated singly in the centrifugal hydroextractor .

The problem arises, on the other hand, when the user of the dyeing system needs to have two or more basic capacities of the single dyeing apparatuses, which requires the installation of two or more hydroextractors having a different diameter, with all the relative construction and economical problems involved.

An objective of the present invention is consequently to provide a centrifugal hydroextractor for re- movable bobbin-holder shafts which makes it possible to operate, alternatively and in relation to the requirements, with a different number of bobbin-holder shafts coming from dyeing apparatuses having different basic capacities. A further objective of the present invention is to provide a centrifugal hydroextractor for removable bobbin-holder shafts which allows a good flexibility of use, thus contributing to a reduction in the operating costs . Yet another objective of the present invention is to provide a centrifugal hydroextractor for removable bob-

bin-holder shafts which is particularly simple and functional, with reduced costs.

These objectives according to the present invention are achieved by providing a centrifugal hydroextractor for removable bobbin-holder shafts as specified in claim 1.

Further characteristics of the invention are indicated in the subsequent claims.

The characteristics and advantages of a centrifugal hydroextractor for removable bobbin-holder shafts according to the present invention will appear more evident from the following illustrative and non-limiting description, referring to the enclosed schematic drawings, in- which: figure 1 is a partially sectional raised side view of a centrifugal hydroextractor for removable bobbin- holder shafts according to the present invention; figure 2 is a plan view of the centrifugal hydroextractor of figure 1; figure 3 schematically shows, in a raised side view, a dyeing system of bobbins of yarn comprising two dyeing apparatuses having different basic capacities; and figure 4 is a partially sectional plan view of the dyeing system shown in figure 3. It should be noted that in the figures of the en-

closed drawings, only those parts of a centrifugal hydro- extractor for removable bobbin-holder shafts which are essential for a complete understanding of the invention are illustrated and described hereunder, whereas all the accessories and driving and control equipment, which can be obtained traditionally and are well-known to experts in the field, have been omitted.

With particular reference to figures 1 and 2 of the enclosed drawings, these show a centrifugal hydroextrac- tor for removable bobbin-holder shafts, indicated as a whole with the reference number 10. Said hydroextractor 10 comprises a structure or container 12, preferably cylindrical, suspended and oscillating on a supporting structure consisting, in the present embodiment example, of three columns 14. The container 12 contains in its interior a basket 16 rotatingly positioned around a central vertical axis A by means of driving devices 36 which are described in more detail hereunder.

A plurality of perforated tubes 18, 18' is housed on the basket 16, in each tube a single bobbin-holder shaft 20 can be inserted to effect dehydration by centrifuga- tion as a result of the rotation of the basket 16 inside the container 12.

Advantageously, according to the present invention, the perforated tubes 18, 18' are arranged annularly in

distinct groups, on the basket 16, along two or more concentric circumferences 22, 22'. In particular, according to the embodiment example illustrated, a first group of perforated tubes 18 is positioned along a first more ex- ternal circumference 22 with respect to the perimetric wall of the container 12, whereas a second group of perforated tubes 18' is positioned along a second more internal circumference 22' with respect to the first circumference 22 and concentric with respect to this. Both of the circumferences 22 and 22' are therefore concentric with respect to the above rotation axis A and the number of perforated tubes 18' situated along the more internal circumference 22' is obviously lower than the number of perforated tubes 18 positioned along the more external circumference 22.

The perforated tubes 18, 18' are all cylindrically- shaped and are arranged vertically, along axes parallel to the rotation axis A of the tube-holder basket 16. The upper portion or inlet mouth 24 and 24' of said perfo- rated tubes 18 and 18' conveniently have a truncated- conical shape, with the larger base facing upwards, to facilitate the introduction of the bobbin-holder shafts 20 in their interior. The lower portion of the perforated tubes 18 and 18', on the other hand, has a flat bottom, with a central hole suitable for allowing the passage of

the base cone 26 of each bobbin-holder shaft 20 and suitably dimensioned so as to allow the movement, in a radial direction, of the bobbin-holder shafts 20 themselves, caused by the centrifugal force during the rota- tion of the basket 16.

The container 12 therefore comprises an upper closing lid 28 inside which a safety device is housed, consisting of at least two concentric rings 30 and 30', substantially horizontal and integral with a central pin 32 coaxial to the central axis A. Each ring 30, 30' is positioned in correspondence with one of the circumferences 22, 22' on which the respective groups of perforated tubes 18 and 18' lie. The pin 32 is housed in a corresponding seat 34, equipped with ball bearings, positioned below the lid 28, so as to allow the concentric rings 30 and 30' to rotate if the bobbin-holder shafts 20 rest thereon, tending to exit from the respective perforated tubes 18 and 18' due to possible vibrations.

The activating means 36 of the basket 16 consist, in the embodiment example illustrated, of a driving motor which, if of the electric type, is activated by an inverter so as to rotate the tube-holder basket 16 at the same number of different speeds corresponding to the number of concentric circumferences along which the distinct groups of perforated tubes 18 and 18' are positioned. In

particular, in the case of only two concentric circumferences 22 and 22', the basket 16 can alternatively rotate at two different velocities, depending on whether the bobbin-holder shafts 20 are positioned in the tubes 18 situated along the outer circumference 22 or in the tubes 18' positioned along the more internal circumference 22', thus always subjecting the yarn being treated to the same centrifugal force. In this way, all the yarn bobbins treated inside the centrifugal hydroextractor 10, regard- less of whether they are positioned on the more external 22 or more internal 22' circumference, will have the same residual humidity, an essential condition for their regular and uniform drying.

It should in any case be pointed out that the rota- tion of the tube-holder basket 16, as also the variation in its rotation velocity, can also be obtained with other known driving means, such as for example direct current, hydraulic drive and others, and that these driving means can be positioned differently from what is illustrated in the figure, such as, for example, along the central rotation axis A.

With reference to figures 3 and 4, these show an overall dyeing system of yarn bobbins, firstly consisting of two circular-shaped trolleys 38 and 40, each carrying a series of bobbin-holder shafts 20 positioned on a sin-

gle circumference but in a number varying from trolley 38 to trolley 40 (see figure 4) . The bobbin-holder shafts 20 are ready for being introduced, by means of a tackle 42, into the respective dyeing apparatuses 44 and 46 having different capacities and, at the end of the dyeing phase, said bobbin-holder shafts 20 are transferred from these to a single centrifugal hydroextractor 10 for removable bobbin-holder shafts according to the invention.

The single centrifugal hydroextractor 10, as previ- ously illustrated, is capable of treating both bobbin- holder shafts 20 coming from the dyeing apparatus 44 and those coming from the dyeing apparatus 46, thanks to the two separate groups of perforated tubes 18 and 18' .

Finally, the dyeing system illustrated comprises two different types of dryer 48 and 50, wherein the dryer 50 is specifically designed for the dyeing system, whereas the dryer 48 is a traditional dryer with the sole modification of the relative trolley 52.

Other known types of dryers, such as pressure dry- ers, radiofrequency dryers, etc. can also be used for this latter drying operation of the yarn bobbins.

The use of the hydroextractor 10 according to the invention is also possible when the dyeing apparatuses 44 and 46 are used with partial capacity, provided the in- troduction of filling devices (not illustrated) or the

exclusion, when possible, of some boilers are effected symmetrically, to allow a balanced rotation of the basket 16.

It can thus be seen that the centrifugal hydroex- tractor for removable bobbin-holder shafts according to the present invention achieves the purposes specified above, as it can operate with numerous modes of use which allow different quantities of bobbin-holder shafts to be treated. In this way, in the overall dyeing system, it is possible to use dyeing apparatuses having different capacities in relation to production demands, without having to adapt the quantity of yarn to be dehydrated each time to the diameter and consequently to the non- modulatable capacity of traditional centrifugal hydroex- tractors. This allows a reduction in both the overall operating costs of the dyeing system and also in the processing times of the yarns to be dyed.

The centrifugal hydroextractor for removable bobbin- holder shafts of the present invention thus conceived can in any case undergo numerous modifications and variants, all included in the same inventive concept; furthermore, all the details can be substituted by technically equivalent elements. In practice, the materials used, as also the forms and dimensions, can vary according to technical demands.

The protection scope of the invention is therefore defined by the enclosed claims.