Patent Description:
In the field of pasta processing lines, in particular short pasta, such as penne, fusilli, etc., it is known to use a pre-drying and mechanical agitation device, generally referred to as "shaker", in which pasta, after having been extruded, is subjected to mechanical agitation and simultaneous heating, typically by blowing hot air thereon, in order to quickly remove a high quantity of humidity from the just extruded pasta (and therefore still very humid), avoiding, thanks to mechanical agitation, that the various pieces of pasta (precisely because they are very humid) stick to each other before reaching a sufficient degree of surface hardness.

Such shakers of known type comprise a containment structure provided with an inlet opening and an outlet opening for the pasta, inside which there are vibrating shelves that mechanically agitate the pasta, transporting it at the same time from the inlet opening to the outlet opening.

Inside the containment structure there are also heat exchangers, typically finned batteries fed by a thermodynamic circuit in which a heat transfer fluid flows, which warms up an air flow that is generated by fans, and which cyclically passes through such heat exchangers, warming up, and through the pasta that is passing on conveyor belts, removing a certain percentage of humidity thereof.

Such shakers of known type are also provided with an expulsion system that extracts the air from the inside of the containment structure, evacuating it to the environment, and creating at the same time, inside the containment structure, a depression that causes the entry of new ambient air through the inlet opening.

However, these shakers of known type have some drawbacks.

In particular, in such shakers of known type a high and uncontrolled quantity of air at ambient temperature and humidity enters through the inlet opening, with consequent high energy expenditure to warm up the drying air (since the entry of air at ambient temperature cools down the environment inside the containment structure, requiring a high heat supply through the heat exchangers to compensate for such cooling).

Furthermore, an uncontrolled introduction of air from the external environment entails, in order to prevent too high pressures from being established inside the shaker, having to expel, through the expulsion system, a high quantity of air from the inside of the shaker; given that the external air is typically much drier than that present inside the shaker (because of the humidity that evaporates from the pasta), this entails an excessive decrease in the internal humidity, with consequent risk of formation of cracks and chromatic unevenness in the pasta treated in the shaker.

<CIT> discloses a chamber dryer comprising a drying chamber, a feeding of a mass of damp material to be treated, an inlet for a mixture of hot gases, an outlet for a portion of heavy dried material and an outlet for conveyor air; the drying chamber is a fixed chamber comprising at least one conveyor bed of the damp material to be treated consisting of a series of adjacent rotating elements having an adjustable interaxis, in which two adjacent rotating elements define a gaugable passage opening.

<CIT> discloses a machine having a tunnel structure which defines a chamber with inclined, downwardly converging longitudinal side walls and in which a substantially horizontal conveyor for conveying a layered flow of shredded tobacco from the input end to the output end of the chamber extends adjacent the lower edges of the converging side walls.

<CIT> discloses a process for pre-drying macaroni using slightly warmed fresh air and dry wheat powder.

The main task of the present invention is to solve the problems listed above, and therefore to realize a pre-drying and mechanical agitation device for the production of pasta (a so-called shaker), which has a reduced energy consumption with respect to the aforementioned known technique.

As part of this task, another aim of the invention is to realize a pre-drying and mechanical agitation device for the production of pasta that allows to maintain a relatively high degree of humidity within the pasta treatment region.

Yet another aim is to realize a pre-drying and mechanical agitation device for the production of pasta that allows to obtain a relatively structurally and chromatically uniform pasta.

The task and purposes according to the present invention are achieved by a pre-drying and mechanical agitation device for the production of pasta comprising:.

wherein the bypass conduit is defined between an internal surface of the containment structure and a wall of a containment case, internal to the containment structure, which at least partially contains the agitation and transport means and the heating means.

Other advantageous features of the invention are reported in the dependent claims.

The features and advantages of the present invention will be more apparent from the following description, which is to be understood as exemplifying and not limiting, with reference to the appended schematic drawings, wherein:.

With reference to the appended figures, a pre-drying and mechanical agitation device for the production of pasta has been indicated as a whole with the number <NUM>.

Such a device <NUM> may advantageously be part of a pasta production plant which may comprise other devices, not illustrated, operatively connected upstream (for example a pasta die) and downstream (for example a drier and a cooler) of the device <NUM>.

The device <NUM> advantageously comprises electronic control means, not illustrated, configured for controlling one or more functions of the device <NUM> itself; advantageously, such electronic control means may comprise, for example, a microprocessor, or a microcontroller, or a programmable logic controller (PLC), etc..

The device <NUM> comprises a containment structure <NUM>, such as for example a metal casing, the inside of which is in fluid communication with the external environment <NUM> through an inlet opening <NUM> and an outlet opening <NUM> for the pasta <NUM>.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, the device <NUM> comprises suction and expulsion means <NUM> of the air contained in the support structure <NUM> and/or of the air just exited from the outlet opening <NUM>.

In an advantageous embodiment, said suction and expulsion means <NUM> comprise one or more suction ports (for example a suction port <NUM> located at the outlet of the outlet opening <NUM>, and a suction port <NUM>, communicating with the interior of the containment structure <NUM>) for sucking the air contained in the support structure <NUM> and/or the air just exited from the outlet opening <NUM>.

Advantageously, the suction and expulsion means <NUM> also comprise a system of piping <NUM> for conveying the air sucked in from the one or more suction ports in a desired region or zone external to the containment structure <NUM>, for example the external environment <NUM>.

Advantageously, the suction and expulsion means <NUM> comprise suction means <NUM>, such as for example a pump, which generate the suction action that causes the suction of the air from the one or more suction ports, and the transport thereof through the system of piping <NUM>.

In an advantageous embodiment, the suction and expulsion means <NUM> further comprise sensor means, not illustrated, such as for example one or more sensors, not illustrated, suitable for detecting the pressure and/or the temperature and/or the humidity inside the containment structure <NUM>, and adjustment means, not illustrated, for example a modulation valve, not illustrated, operatively connected to said sensor means, preferably through the electronic control means of the device <NUM>, if present, for regulating the quantity of air expelled through the suction and expulsion means <NUM> as a function of the pressure and/or the temperature and/or the humidity internal to the support structure <NUM>.

According to the invention, the device <NUM> further comprises selective introduction means <NUM> of air from the outside to the inside of the containment structure <NUM>, through the inlet opening <NUM>, configured to define an at least partial barrier to the entry of further air, excluding the one introduced by the selective introduction means <NUM> themselves, through the inlet opening <NUM>.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, the selective introduction means <NUM> are positioned outside the containment structure <NUM>; in other advantageous embodiments, not illustrated, said selective introduction means <NUM> can be positioned inside the containment structure <NUM>, or partially inside and partially outside the containment structure <NUM>.

In an advantageous embodiment, said selective introduction means <NUM> comprise means for generating <NUM> an air blade <NUM>, advantageously warmed up, which is introduced into the inlet opening <NUM>, defining a partial barrier to the entry of further air, excluding the air blade <NUM> itself, through the inlet opening <NUM>.

The air blade <NUM>, in particular if warmed up, also contributes to thermally isolating the interior of the containment structure <NUM> from the external environment <NUM>.

Within the containment structure <NUM> there are agitation and transport means <NUM>, suitable for mechanically agitating pasta <NUM>, transporting it at the same time from the inlet opening <NUM> to the outlet opening <NUM>.

In an advantageous embodiment, the agitation and transport means <NUM> comprise one or more vibrating shelves (in the advantageous example illustrated in the appended figures are three shelves, indicated respectively with the numbers 7a, 7b and 7c), positioned inside the containment structure <NUM>, suitable for housing the pasta <NUM> which enters the containment structure <NUM> through the inlet opening <NUM>; such one or more vibrating shelves 7a, 7b, 7b advantageously have a perforated structure (or in other words they have through holes obtained on their surface, so that they can be crossed by an air flow) and have a substantially rectangular conformation in plan.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, inside the containment structure <NUM> there are a plurality of vibrating shelves (three shelves 7a, 7b and 7c in the advantageous example of the appended figures), arranged the one above the other, advantageously at a predetermined mutual distance (not necessarily the same for all pairs of superimposed shelves), and they are advantageously arranged, in plan, staggered from one another, such that the pasta <NUM> which, because of the vibration, comes out from one end of an upper shelf (for example the shelf 7c in the appended figures), falls onto the shelf arranged immediately below it (for example the shelf 7b in the advantageous example of the appended figures); in this way the pasta that enters from the inlet opening <NUM>, after having travelled, being agitated, along a first vibrating shelf (for example shelf 7c), passes gradually from a shelf to the lower shelf (for example from 7c to 7b), until reaching a last vibrating shelf (7a in the advantageous example of the appended figures) which communicates with the outlet opening <NUM>, finally exiting from the latter by the action of vibration.

According to the invention, the device <NUM> comprises heating means <NUM>, suitable for heating an air flow that passes through them.

Advantageously said heating means <NUM> comprise one or more heat exchangers, for example, in the advantageous case illustrated in the appended figures, three heat exchangers, indicated respectively with the numbers 9a, 9b, 9c, comprising for example one or more finned batteries fed by a heat transfer fluid, suitable for heating an air flow that passes through them.

Advantageously, the supply of the heat transfer fluid to the one or more finned batteries can be controlled by a special thermodynamic circuit, not illustrated, controlled for example by the electronic control means of the device <NUM>.

The device <NUM> comprises ventilation means <NUM>, for example fans <NUM>, preferably with axial flow, suitable for generating one or more air flows, illustrated schematically in <FIG> and <FIG> with arrows <NUM>, which pass through the heating means <NUM> and the agitation and transport means <NUM>, so as to hit pasta <NUM> when it is transported by them, and then return cyclically in the ventilation means <NUM>.

In particular, according to the invention, the ventilation means <NUM> comprise a delivery region 10a, from which the one or more air flows <NUM> exit, and a suction region 10b, through which at least part of the one or more air flows <NUM> cyclically return in the ventilation means <NUM>; it is emphasized that a part of the one or more air flows <NUM> that is generated by the ventilation means <NUM> may not cyclically return in said ventilation means <NUM>, in that, for example, it may be emitted outside the containment structure <NUM>, for example by the suction and expulsion means <NUM>.

Advantageously, as in the advantageous embodiment illustrated in the appended figures, the ventilation means <NUM> are positioned below the agitation and transport means <NUM>.

In the advantageous embodiment illustrated in the appended figures, one or more air flows <NUM>, after being generated by the ventilation means <NUM>, first pass through a first heat exchanger 9a, warming up, then a first vibrating shelf 7a, transferring heat to said first vibrating shelf 7a and to the pasta <NUM> contained therein, then a second vibrating shelf 7b, transferring heat to said second vibrating shelf 7b and to the pasta <NUM> contained therein, then a second heat exchanger 9b, warming up, a third vibrating shelf 7c, transferring heat to said third vibrating shelf 7c and to the pasta <NUM> contained therein, and finally a third heat exchanger 9c, warming up.

Subsequently, all or part of the one or more air flows <NUM> are sucked from the suction region 10b of the ventilation means <NUM>, re-entering the same and then being re-emitted from the delivery region 10a of the ventilation means <NUM> towards the first heat exchanger 9a.

Thus, inside the containment structure <NUM>, a circulation of the one or more flows <NUM> is established which affects the heating means <NUM>, the agitation and transport means <NUM> (and the pasta <NUM> contained therein) and the ventilation means <NUM>.

According to the invention, the device <NUM> further comprises a bypass conduit <NUM> that puts the delivery region 10a of the ventilation means <NUM> in fluid communication with the inlet opening <NUM>, bypassing the agitation and transport means <NUM> and the heating means <NUM>.

A part of the one or more air flows <NUM> generated by the ventilation means <NUM>, for example the flow part indicated with arrows 11a in <FIG>, instead of heading towards the heating means <NUM> and the agitation and transport means <NUM>, enters the bypass conduit <NUM>, crosses it, and exits inside the containment structure <NUM>, near the inlet opening <NUM>.

In this way, the depression that is created near said inlet opening <NUM> due to the circulation of the one or more air flows <NUM> that, after passing through the heating means <NUM> and the agitation and transport means <NUM>, are sucked in by the suction region 10b of the ventilation means <NUM>, and due to the suction operated by the suction and expulsion means <NUM>, is compensated for by the pressure exerted by the part 11a of the one or more air flows <NUM> that exit the bypass conduit <NUM>, thus preventing such depression from sucking in an uncontrolled manner air from the external environment <NUM> inside the containment structure <NUM>, through the inlet opening <NUM>.

The bypass conduit <NUM> is defined between the internal surface 2a of the containment structure <NUM> and a wall 70a of a containment case <NUM>, internal to the containment structure <NUM>, which at least partially contains the agitation and transport means <NUM> and the heating means <NUM>; advantageously, the bypass conduit <NUM> communicates with the delivery region 10a of the ventilation means <NUM> through one or more through openings <NUM> made in the wall 70a of the containment case <NUM>.

In an advantageous embodiment, such as the one illustrated in the appended figures, the device <NUM> further comprises conveying means <NUM> suitable for conveying the dust <NUM> transported by the one or more air flows <NUM> into one or more accumulation and decantation regions <NUM> present inside the containment structure <NUM>.

Advantageously, the one or more accumulation and decantation regions <NUM> communicate with the outside of the containment structure <NUM> through one or more discharge openings <NUM>.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, the conveying means <NUM> comprise one or more bulkheads 12a positioned laterally to the agitation and transport means <NUM> to guide the one or more air flows <NUM>, after they have passed through the agitation and transport means <NUM>, and before they return to the ventilation means <NUM>, towards the one or more accumulation and decantation regions <NUM>, such that said one or more air flows <NUM> deposit, by gravity, at least part of the dust <NUM> present therein.

Advantageously, the one or more bulkheads 12a have, in a section operated according to a plane transverse to the device <NUM>, such as for example plane III-III of <FIG>, a substantially C-shaped conformation, advantageously with the concavity facing the agitation and transport means <NUM>; in such an advantageous embodiment, between a bulkhead 12a and the adjacent containment structure <NUM> a channel 12b is defined for the passage of one or more air flows <NUM>, which leads the same into one of the one or more accumulation and decantation regions <NUM>.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, wherein the agitation and transport means <NUM> comprise one or more vibrating shelves (for example the three vibrating shelves 7a, 7b and 7c arranged one above the other, as in the advantageous embodiment illustrated in the appended figures) with a substantially rectangular plan, the bulkheads 12a are at least two, and are positioned respectively at the two long sides of the two or more shelves (for example 7a, 7b 7c).

In the advantageous embodiment wherein the ventilation means <NUM> are positioned below the agitation and transport means <NUM>, such as for example the one illustrated in the appended figures, the one or more accumulation and decantation regions <NUM> are advantageously positioned below and laterally with respect to the ventilation means <NUM>; in this way the one or more air flows <NUM>, in order to return to the ventilation means <NUM>, must first descend into one of the one or more accumulation and decantation regions <NUM>, and then rise therefrom, which favours in said region the decantation and the accumulation of the dust <NUM> contained in the one or more air flows <NUM>.

Advantageously, in the case where the agitation and transport means <NUM> comprise one or more vibrating shelves (for example the three vibrating shelves 7a, 7b and 7c arranged one above the other, as in the advantageous embodiment illustrated in the appended figures), the one or more accumulation and decantation regions <NUM> can be advantageously positioned below and laterally with respect to the one or more vibrating shelves (for example to the three vibrating shelves 7a, 7b and 7c) and to the ventilation means <NUM>.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, the one or more accumulation and decantation regions <NUM> are at least partially defined by one or more profiles <NUM> preferably having a concave cross-section, preferably substantially "V" shaped, with the vertex facing away from the conveying means <NUM>; such "V"-shaped conformation favours the decantation and the accumulation of the dust <NUM> near the vertex of the "V" itself.

In an advantageous embodiment, the device <NUM> further comprises automatic extraction means <NUM> positioned at least partially in the one or more accumulation and decantation regions <NUM> for automatically removing the dust <NUM> therefrom and transporting it outside the containment structure <NUM>.

In an advantageous embodiment, such as for example the one illustrated in the appended figures, the automatic extraction means <NUM> comprise one or more augers <NUM> arranged in such a way as to transport the dust <NUM> present in the one or more accumulation and decantation regions <NUM> up to the respective one or more discharge openings <NUM>, communicating with the outside of the containment structure <NUM>, for example with a dust collection tank <NUM>, not illustrated, external to the device <NUM>.

In other advantageous embodiments, not illustrated, the automatic extraction means <NUM> advantageously comprise other mechanical systems, such as for example a conveyor belt, not illustrated, arranged at least partially inside an accumulation and decantation region <NUM>, on which the dust <NUM> is deposited to be transported outside the containment structure <NUM>.

The operation of the device <NUM> is described below.

The pasta <NUM>, generally immediately after exiting the respective die, not illustrated, is introduced into the containment structure <NUM> through the inlet opening <NUM>, and is deposited on the agitation and transport means <NUM> (for example, with reference to the appended figures, on the shelf 7c), which start vibrating, causing agitation and a simultaneous advancement of the pasta <NUM> through the containment structure <NUM> (in the example illustrated in the appended figures passing it first in the second shelf 7b and in the third shelf 7a), up to the outlet opening <NUM>.

By activating the selective introduction means <NUM> of air from the outside to the inside of the containment structure <NUM>, an at least partial barrier to the entry of further air is created, excluding the one introduced by the selective introduction means <NUM> themselves, through the inlet opening <NUM>.

In the advantageous case where said selective introduction means <NUM> comprise means for generating <NUM> an air blade <NUM>, in particular in the case where said air blade <NUM> is warmed up, the same also contributes to thermally isolating the interior of the containment structure <NUM> from the external environment <NUM>.

By activating the suction and expulsion means <NUM>, a part of the air present inside the containment structure <NUM> and/or the air exiting the outlet opening <NUM> are sucked and expelled into a desired region of the external environment <NUM>; in this way the pressure inside the containment structure <NUM> is prevented from reaching too high values, which could compromise the correct drying of the pasta <NUM>.

In the advantageous embodiment wherein the suction and expulsion means <NUM> comprise the sensor means and the adjustment means described above, by means of the same it is possible to regulate the quantity of air expelled through the suction and expulsion means <NUM> as a function of the pressure and/or of the temperature and/or of the humidity internal to the support structure <NUM>.

The activation of the ventilation means <NUM> creates, inside the containment structure <NUM>, the circulation of one or more air flows <NUM>, which pass through the heating means <NUM>, warming up, and the pasta <NUM>, warming it up and removing humidity therefrom.

The circulation of the one or more air flows <NUM> which, after passing through the heating means <NUM> and the agitation and transport means <NUM>, are sucked by the suction region 10b of the ventilation means <NUM>, together with the suction action of the suction and expulsion means <NUM>, creates, near the inlet opening <NUM>, a depression which would tend, despite the presence of the selective introduction means <NUM>, to suck air from the external environment <NUM>, through the inlet opening <NUM>; however, thanks to the bypass conduit <NUM>, air is sent from the delivery region 10a of the ventilation means <NUM> to the zone near the inlet opening <NUM>, thus compensating for this depression, and preventing the uncontrolled entry of ambient air into the containment structure <NUM> through the inlet opening <NUM>.

Furthermore, it has been observed that, both because of the mechanical agitation and the erosion action exerted by the air, a high quantity of dust <NUM>, which is circulated from the one or more air flows <NUM> inside the containment structure <NUM>, can be separated from the pasta <NUM>.

In an advantageous embodiment, the conveying means <NUM>, if advantageously present in the device <NUM>, by creating preferential paths for the circulation of the one or more air flows <NUM>, contribute to conveying the dust <NUM> transported by said one or more air flows <NUM> in the one or more accumulation and decantation regions <NUM>, if advantageously present in the device <NUM>, where said dust <NUM> settles by effect of gravity, and accumulates, avoiding returning into circulation with the air.

In an advantageous embodiment, as the dust <NUM> is deposited in the one or more accumulation and decantation regions <NUM>, if advantageously present, the automatic extraction means <NUM>, if advantageously present, automatically remove said dust <NUM> from the one or more accumulation and decantation regions <NUM>, transporting it outside the containment structure <NUM>, and thus reducing the risk of said dust <NUM> circulating again inside the containment structure <NUM>, with the risks that this would entail.

It has thus been found that the pre-drying and mechanical agitation device for the production of pasta according to the invention solves the task and the purposes stated above; in fact, thanks to the selective introduction means of air described above, in combination with the use of the bypass conduit to compensate for the depression that is generated both due to the circulation of the air generated by the ventilation means, and to the expulsion of the air through the suction and expulsion means, the quantity of air at ambient temperature and humidity that enters uncontrollably through the inlet opening is reduced, which results in a lower energy consumption and in a more effective maintenance of the humidity inside the containment structure (which allows to obtain a pasta with good characteristics of structural and chromatic uniformity).

Claim 1:
Pre-drying and mechanical agitation device (<NUM>) for the production of pasta comprising:
- a containment structure (<NUM>), provided with an inlet opening (<NUM>) and an outlet opening (<NUM>) for pasta (<NUM>);
- agitation and transport means (<NUM>), suitable for mechanically agitating pasta (<NUM>), transporting it at the same time from said inlet opening (<NUM>) to said outlet opening (<NUM>);
- heating means (<NUM>), suitable for heating an air flow (<NUM>) that passes through them;
- ventilation means (<NUM>), suitable for generating one or more air flows (<NUM>) which pass through said heating means (<NUM>) and said agitation and transport means (<NUM>), and then, at least in part, return cyclically in said ventilation means (<NUM>), wherein said ventilation means (<NUM>) comprise a delivery region (10a), from which said one or more air flows (<NUM>) exit, and a suction region (10b), through which at least part of said one or more air flows (<NUM>) cyclically re-enters said ventilation means (<NUM>); characterized in that
- suction and expulsion means (<NUM>) of the air contained in said support structure (<NUM>) and/or of the air exited from said outlet opening (<NUM>) ;
- selective introduction means (<NUM>) of air from the outside to the inside of said containment structure (<NUM>), through said inlet opening (<NUM>), configured to define an at least partial barrier to the entry of further air, excluding the one introduced by said selective introduction means (<NUM>) themselves, through said inlet opening (<NUM>);
- a bypass conduit (<NUM>) which puts said delivery region (10a) of said ventilation means (<NUM>) in fluid communication with said inlet opening (<NUM>), bypassing said agitation and transport means (<NUM>) and said heating means (<NUM>), wherein
said bypass conduit (<NUM>) is defined between an internal surface (2a) of said containment structure (<NUM>) and a wall (70a) of a containment case (<NUM>), internal to said containment structure (<NUM>), which at least partially contains said agitation and transport means (<NUM>) and said heating means (<NUM>).