FIELD OF THE INVENTION

The present invention concerns a metal reel used in the textile industry.

By reel we mean the component onto which any type of yarn is wound, in this case the reel is a metal reel that mainly serves to wind a bobbin of thread, normally synthetic thread or silk.

BACKGROUND OF THE INVENTION

Metal reels are known, used to wind for example synthetic yarns such as threads for women's stockings or other yarns, which comprise a cylindrical body with two axial compartmentation flanges.

Both the cylindrical body and the flanges are normally axially provided with a hole.

It is known that the considerations and aspects concerning the winding of the bobbins dealt with in the text are also valid for unwinding, and that the reels can also be used for winding natural yarns, such as silk and mixed yarns for example.

Known reels have cylindrical bodies onto which the yarn is wound, with a diameter comprised between 34mm and 38mm with axial compartmentation flanges with a diameter comprised between 53mm and 150mm.

Such reels have a plurality of problems connected both with their manufacture and with their use, which makes them not very economical or efficient.

Known metal reels have a heavy structure which entails a high energy use both to manufacture them and also to start their spooling rotation.

In particular, in the case of spinning machines configured to wind a plurality of reels simultaneously, the overall number of reels entails a significant use of energy.

It is known that, since the material used is aluminum or other expensive light material, the weight of each reel greatly affects the overall manufacturing cost, both in terms of material and in terms of energy needed to obtain the finished reel.

To this must be added the fact that, since the radial size of the cylindrical bodies is important for the purposes of calculating the moment of inertia for each reel, and therefore the overall power needed to make the reels rotate, current reels involve considerable inertia.

It is also known that, especially during the start-up of the winding motors, the greater the power needed for each reel, the greater are the mechanical vibrations associated with them. This affects the need for very expensive machines, suitable to support these stresses.

Until today, there have been many attempts to perfect metal reels to obtain a useful result, at the same time maintaining a volume of windable yarn. Until now, the state of the art has mainly dealt with the materials and construction methods of reels.

If they are made lighter while the sizes remain the same, known metal reels have the disadvantage that they deform due to the pinch effect of the yarn being wound.

After the structure of the cylindrical body has deformed, the yarn no longer winds on a defined cylindrical surface, but on a deformed surface which causes non-uniform cones.

There is therefore a need to perfect the state of the art and make available a metal reel that overcomes at least one of the disadvantages of the state of the art.

The purpose of the present invention is to obtain a metal reel that is light, economical, less wasteful in terms of energy and base material, and that also preserves over time its geometric characteristics during the winding and/or unwinding operations.

The inventive idea allows to improve and perfect the state of the art, improving the properties of inertia and at the same time increasing both the capacity of spatial winding and also the speed of the winding and unwinding operations.

Another purpose of the present invention is to obtain a metal reel that allows to reduce transport and storage costs.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claim, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, the present invention provides a reel, advantageously but not necessarily of an aluminum base, that comprises a cylindrical body and two axial compartmentation end flanges. Inside the cylindrical body and the flanges a through hole is advantageously made.

Hereafter reference will be made, and also in the claims, to better identify the inventive idea, to a reel made of aluminum alloy.

According to the invention the diameter of the cylindrical body that is currently comprised between 34mm and 38mm is reduced by a value comprised between 25% and 35%, advantageously comprised between 28% and 32%, even more advantageously comprised between 29% and 30%.

According to the invention the cylindrical body has an axial hole that determines a circumferential wall with a thickness that varies from 2.0mm to 4.0mm, normally by a value comprises between 3.3mm and 3.6mm.

According to the invention the flanges can have known sizes, that is, a value comprised between 53mm and 150mm, advantageously between 75mm and 95mm.

A reel according to the present invention allows to obtain the following characteristics compared with the state of the art:

- a lesser weight of the reel that varies from about 6% to 20%, thus saving material and energy to obtain it;

- a lower moment of inertia of the reel that varies from 12% to 37%, with reduced energy required to make it rotate and to stop it;

- a moment of inertia of the reel, together with the yarn wound on it, given the same volume of yarn wound, which is up to 25% less, with the connected advantage in handling it.

Moreover, according to the invention, the reel allows to increase the yarn contained between the flanges, compared with the state of the art, which can amount to 35% in terms of volume of yarn.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example, with reference to the attached drawings wherein: - fig. 1 shows a front view of a reel for a spinning machine according to the state of the art;

- fig. 2 shows a front view of a reel for a spinning machine according to the present invention;

- fig. 3 shows a table 1 showing the variations in the moments of inertia and weight as a function of some parameters of size of a reel according to the state of the art and a reel according to the present invention.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

With reference to the attached drawings, which show non-restrictive examples of the invention, we will now describe some embodiments of a reel 10 for a spinning machine.

According to one embodiment, the reel 10 for a spinning machine comprises a cylindrical body 11 and two compartmentation flanges 12, each coupled solidly with an end of the cylindrical body 11 and are conformed, for example, like a disc with a thickness (tl) comprised between 4mm and 7mm, advantageously with a thickness of around 5.5mm.

According to one embodiment, the cylindrical body 1 1 and the two flanges 12 have an axial through hole 13, which defines a compartment 14 that also has a lightening function.

According to one embodiment, the reel 10 is made of metal, such as for example aluminum or other metals and/or metal alloys or other materials suitable to resist the pinch effect of the yarn on the external surface 14 of the cylindrical body 11.

Figs. 1 and 2 show two metal reels: a first known reel 1 10 and a second reel 10 according to the present invention.

The drawings also show the geometric sizes on which the Applicant has acted in order to optimize and perfect the state-of-the-art structure.

In particular, the drawings show:

- the external diameter (dl) of the known cylindrical body 1 1 1 and the external diameter (d2) of the cylindrical body 1 1 ;

- the diameter of the axial hole (Fl) of the known reel 110 and the diameter of the axial hole (F2) of the reel 10;

- the diameter of the flanges (Dl) of the known flanges 112 and the diameter of the flanges (D2) of the flanges 12;

- the longitudinal length (SI) of the known cylindrical body 11 1 and the longitudinal length (S2) of the cylindrical body 1 1.

The geometric sizes of the reel 10 have been studied and optimized to obtain a reel 10 able to be used, during the winding of a yarn, with lesser use of energy and at the same time maintaining the resistance of the cylindrical body 11 to the pinch effect induced by the yarn on the external surface of the cylindrical body 1 1.

With reference to the parameters of size of the reel 10, these have been studied and tested with different yarns and spooling speeds, so as to be able to optimize both the relational factors between the measurements and also the intervals inside which the measurements must remain, in order to obtain a plurality of purposes and advantages.

In particular, priority was given not only to the stability of the reel 10, but also to its ability to stably contain the yarn wound, and to the reduced moment of inertia, which factor was considered pre-eminent for the range of advantages it entails.

Indeed, this reduction in inertia allows to use less energy to obtain the necessary raw material, to perform the necessary operations to obtain the reel 10 and finally to wind and also unwind the yarn onto/from the reel 10. It also allows to increase at least the starting speed ramp.

According to an advantageous form of the present invention, the cylindrical body 1 1 has an external diameter (d2) reduced with respect to the external diameter (dl) of the known cylindrical body 1 1 1 by a value comprised between 25% and 35%, advantageously comprised between 28% and 32%, even more advantageously comprised between 29% and 30%.

According to one embodiment, the cylindrical body 11 has an axial hole 13 that determines a circumferential wall 15 with a thickness that varies between 2.0mm and 4.0mm, preferably a value comprised between 3.3mm and 3.6mm. In one embodiment of the present invention, the circumferential wall 15 has a thickness equal to about 3.5mm.

These sizes allow to obtain, compared with the state of the art:

- a lower weight of the reel 10 that varies from 6% to 20%;

- a reduced moment of inertia of the reel 10 that varies from 12% to 37%;

- a moment of inertia of the reel 10 plus the wound yarn, given the same volume of wound yarn, which is less by up to 25%.

According to one embodiment of the present invention, the external diameter (d2) of the cylindrical body 1 1 is comprised between 24mm and 28mm, advantageously equal to 26mm. The diameter of the axial hole (F2) is comprised between 18mm and 21mm, advantageously equal to 19mm.

According to one embodiment of the invention, the ratio between the external diameters of the cylindrical bodies of the state of the art (dl) and of the present invention (d2) is comprised between 1.20 and 1.60, and is advantageously equal to 1.40.

According to a variant of the invention, the longitudinal length (S2) of the cylindrical body 1 1 is comprised between 1 10mm and 180mm, normally comprised between 130mm and 170mm.

According to a variant, the diameter of the flanges (D2) is comprised between 53mm and 150mm.

These ratios in size allow to obtain a capacity for containing the yarn between the flanges 12 that is greater than the known reel 1 10 by as much as 35% in terms of volume of yarn.

By way of non-restrictive example, Table 1 shows some examples:

- the variations in the moments of inertia of the reel 10 compared to the known reel 1 10 (AI _R ), the overall moments of inertia of the reel 10 with a quantity of yarn compared with the known reel 10 with the same quantity of yarn (AI _X );

- the variations in weight of the reel 10 compared with the known reel 110 (AP _R ).

The variations shown in Table 1 refer to a reel 10 with its flanges 12 having a thickness equal to 5.5mm and made of a metal with a density equal to 2.75g/cm ^J , a yarn with a density equal to 0.78 g/cm ^J for a total volume occupied of about 740cm ³ .

Furthermore, the values shown in Table 1 refer to a reel 10 with an external diameter (d2) of the cylindrical body 11 equal to 26mm and a diameter of the hole 13 (F2) equal to 19mm, compared with a reel 110 with an external diameter (dl) of the known cylindrical body 11 equal to 36.5mm.

Illustrating the data in Table 1, fixing the external diameter (d2) of the cylindrical body 1 1 with respect to a known cylindrical body 1 11 with external diameter (dl), it is obvious that the advantages of the present invention are confirmed for a range of reels 10 according to the present invention with other variable parameters.

With reference to Table 1, it is confirmed that the parameters of size of a reel 10 according to the present invention are such that the advantage is obtained of a reel 10 that is lighter and has lower moments of inertia compared with a known reel 1 10, which entails a reduction in the energy needed to make the reel 10 rotate, and also the advantages described above.

Furthermore, the parameters of size are demonstrated so as to guarantee that the cylindrical body 11 does not deform under the pinch effect of the yarn.

It is clear that modifications and/or additions of parts may be made to the reel for yarns as described heretofore, without departing from the field and scope of the present invention.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of reel for yarns, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.