The present invention relates to a machine for moulding dough for oven-baked products, of the type comprising:
a hopper open underneath designed to contain the dough to be moulded;
a rotary moulding roll, having on its outer lateral surface a plurality of forming moulds;
a rotary feed roll, configured for pushing the dough coming from said hopper into said moulds of said moulding roll to form semi-finished products, each in a respective mould; and
a conveyor belt for feeding said semi-finished products to stations downstream of said machine, in which said belt runs over said moulding roll for a stretch, coming into contact with said lateral surface of said feed roll in a first angular position around said feed roll, and detaching from said lateral surface in a second angular position downstream of said first angular position, with reference to the direction of rotation of said roll, so as to remove said semi-finished products from said forming moulds.
A machine of the type referred to above is, for example, described in the documents Nos. EP1142478 and U.S. Pat. No. 4,155,691.
The object of the present invention is to provide a machine of the type referred to above that will be an improvement over the machines of the prior art, in particular in order to achieve one or more of the following advantages:
a higher quality of production, in particular for products having complex shapes or multiple thicknesses;
a higher efficiency of production, in particular reducing the number of broken and incomplete moulded products;
ease of assembly and disassembly of components of the machine;
improved possibility of setting and regulation of the machine; and
higher versatility of use as regards the types of dough and the shapes of the products to be obtained.
The machine forming the subject of the present invention is defined by the characteristics specified claim 1. The present invention moreover regards a moulding process according to claim 11.
The claims form an integral part of the technical teaching provided herein in relation to the invention.
Further characteristics and advantages of the invention will emerge clearly from the ensuing description with reference to the annexed drawings, which are provided purely by way of non-limiting example and in which:
In the ensuing description, specific details are illustrated aimed at enabling an in-depth understanding of the embodiments. The embodiments may be provided without one or more of the specific details, or with other methods, components, or materials, etc. In other cases, known structures, materials, or operations are not illustrated or described in detail so that various aspects of the embodiment will not be obscured.
The references used herein are only provided for convenience and hence do not define the sphere of protection or the scope of the embodiments.
The moulding machine described herein is of the rotary-moulding type. An example of application of the machine described herein regards moulding dough for biscuits.
In general, according to the type in question, the machine described herein comprises:
a hopper open underneath designed to contain the dough to be moulded;
a rotary moulding roll, having on its outer lateral surface a plurality of forming moulds;
a rotary feed roll, configured for pushing the dough coming from the hopper into the moulds of the moulding roll, to form semi-finished products, each in a respective mould;
a conveyor belt for feeding the semi-finished products to subsequent processing stations, wherein the belt runs over the moulding roll for a stretch, coming into contact with the lateral surface of the feed roll in a first angular position around the feed roll, and detaching from the lateral surface in a second angular position downstream of the first position, with reference to the direction of rotation of the feed roll, so as to remove the semi-finished products from the forming moulds.
The moulding roll 200 and the feed roll 202 are arranged opposed to one another underneath the hopper 204, receiving the dough fed through the bottom of the hopper in the space comprised between them. Their axes of rotation are arranged in one and the same substantially horizontal plane. The two rolls 200 and 202 turn in opposite directions so as to pull the dough downwards; in the example illustrated, the moulding roll 200 turns in a counterclockwise direction, and the feed roll 202 in a clockwise direction.
The feed roll 202 acts on the dough through its knurled lateral surface, favouring flow thereof downwards and pressing the dough into the mould cavities 200′ of the moulding roll in the area where the two rolls are at the shortest distance apart.
A blade 205 set underneath the two rolls, in a vertical position, separates the dough contained in the mould cavities 200′ from the dough that remains adherent to the feed roll 202.
The conveyor belt 206, which extends according to a closed loop around a plurality of rotary rolls via which it is moved, moves into contact with the moulding roll 200 in the angular position of 270° and runs over it for a limited stretch until the angular position of 315° is approximately reached, where it starts to separate from the roll 200. Incidentally, it should be noted that the angular positions indicated here and in what follows refer to the goniometric circumference in a cartesian plane set orthogonal to the axis of rotation of the moulding roll and with the origin of the axes of the co-ordinates positioned so as to coincide with the axis of rotation, where the angles are measured in a counterclockwise direction starting from the point of intersection between the circumference and the positive semi-axis of abscissae (see
Along the above stretch, the belt 206 presses against the semi-finished products contained in the cavities 200′ to get them to adhere, and when the belt 206 separates itself from the moulding roll 200, the semi-finished products remain attached thereto and are extracted from the respective mould cavity as a result of detachment of the belt from the moulding roll.
From this position, the belt 206 proceeds along its path, feeding the semi-finished products to subsequent stations of the production line, for example to a baking station.
As will be said in what follows, the configuration described above presents a series of drawbacks that the moulding machine described herein is designed to overcome.
With reference now to
It comprises two feed rolls 4A, 4B that are positioned underneath the hopper 6, in respective positions opposed to one another with respect to the flow of dough fed through the bottom of the hopper. These rolls are, instead, positioned above the moulding roll 2.
The two feed rolls 4A, 4B are prearranged for turning in opposite directions and have the function of determining a flow of dough directed against the lateral surface of the moulding roll 2. In particular, as may be noted in
As conventionally envisaged in the prior art, the two feed rolls 4 have surfaces with formations in relief, for example knurled surfaces, to favour adhesion of the dough.
The dough that is pushed by the two rolls 4A and 4B against the moulding roll 2 comes to press against the lateral surface of the latter, thus filling the mould cavities 2′.
It should be noted that the above modality of feeding dough is completely different from the one envisaged in the known solution of
The above modality of feed enables a greater control over the dough fed to the moulding roll.
In particular, it is possible to control the pressure with which the dough is pushed into the mould cavities by regulating the speed of rotation of the two feed rolls.
By intervening in this way, it is possible to guarantee a constant quality of production as a function of the type and conditions of the dough. For instance, for particularly hard doughs, without fats and/or sugars and/or water, it is possible to envisage a speed of rotation of the two rolls greater than for applications with softer doughs, rich in fats and/or sugars, this in order to determine a higher pressure that will guarantee total filling of the mould cavities provided on the moulding roll 2.
In this way, it is possible to guarantee optimal filling of the mould cavities for any type of dough.
The machine described herein may comprise a control unit configured for regulating the speed of rotation of the feed rolls 4A and 4B on the basis of the criteria referred to above.
Among other things, the pressures on the dough that can be reached in the machine described herein enable degrees of compacting of the dough to be obtained within the mould cavity that are considerably higher than those obtained in the prior art.
It is consequently possible to obtain semi-finished products even of complex shapes, for which a marked compacting of the dough is necessary to ensure total filling of the mould cavities and guarantee that the products maintain the shape obtained even after they have been removed from the mould cavities.
Complex shapes that may be obtained comprise, for example, products having a three-dimensional structure, such as products shaped like a container, i.e., ones having a bottom and a closed perimetral transverse edge.
On the other hand, it should again be noted that the pressure of the dough in the space comprised between the feed rolls 4A and 4B is determined also by the distance between the two rolls, which can be regulated during setting-up of the machine.
To return to
The direction of rotation of the moulding roll 2 determines the outlet side of the dough from the aforesaid area.
The feed roll that is located on the same side—the roll 4B in the example illustrated in
On the aforesaid outlet side of the dough, set up against the point of minimum distance between the moulding roll 2 and the feed roll 4B, is a blade 5 that is designed to separate the dough contained in the cavities 2′ of the moulding roll 2 from the dough that remains, instead, adherent to the lateral surface of the roll 4B.
This positioning of the blade on the outer side of the set of the rolls 4A, 4B, and 2 facilitates installation thereof, as likewise possible disassembly and re-assembly for purposes of replacement or maintenance, it not being necessary for this purpose to displace or remove the rolls themselves, as instead is the case in machines according to the prior art.
Moreover, thanks to the above positioning, sufficient space is obtained to orient the blade with respect to the moulding roll even according to configurations that depart from the condition of tangency conventionally envisaged in the prior art.
The blade may in particular be oriented in directions incident with respect to the moulding roll, this in order to favour an action thereof of scraping of the dough from the outer surface of the moulding roll.
To return to
However, in the machine described herein, the conveyor belt 8 moves into contact with the lateral surface of the moulding roll 2 in a position advanced with respect to the angular position of 270° envisaged for the belt 206 according to the solution of the prior art (see
In particular, in various preferred embodiments, the belt 8 moves into contact with the moulding roll 2 in a position θ1 comprised between the angular positions of 180° and 270°—in the position of 180° in the example illustrated—and runs over it up to a position θ2 comprised between the positions of 270° and 360°—the position of 360° in the example illustrated.
In the positionθ02, the belt 8 separates from the moulding roll 2 and proceeds its path along a substantially horizontal stretch, through which it feeds the semi-finished products to the subsequent stations.
Thanks to the configuration indicated, the belt 8 comes to press the semi-finished products against the respective mould cavities 2′ along the stretch in which these are located facing downwards as a result of the rotation of said roll.
By so doing, the belt 8 acts as support for the semi-finished products opposing the force of gravity, and keeps the products fixed in position within the respective cavities 2′, preventing any movement thereof.
This guarantees that the products remain in the original correct position within the cavities 2′ until they are released onto the belt 8.
Instead, once again with reference to the known solution of
Consequently, it may happen that, once they have got past the blade 205, as a result of the force of gravity, the products modify their position inside the respective mould cavities, and hence they are then pressed against said cavities by the belt 206, when they are no longer in their original correct position, with the risk of undergoing deformation or getting damaged.
In view of the foregoing, this drawback is, instead, completely overcome in the machine described herein.
It should be noted that the configuration of the belt 8 illustrated in
In particular, the angular positions θ1, θ2 mentioned above may vary as a function of the needs of the various applications.
The angular position θ1 may, for example, be beyond 180° and between the 180° and 270°, in the case where it is possible to guarantee that between 180° and the position θ1 the semi-finished products are not subject to displacements, notwithstanding the absence, in that interval, of the belt 8. On the other hand, the position θ1 may also be before 180°, for example for constructional requirements.
Likewise, the angular position θ2 may be before 360° or even before 270°, according to the possible constructional requirements and requirements of operation of the machine.
In a preferred variant of the machine described herein, the angular position θ1 is around 180° and the angular position θ2 is at 270° or slightly before (
It should now be noted that the angular positions θ1, θ2 mentioned above refer to the case where the machine is pre-arranged with the moulding roll 2 designed to turn in a counterclockwise direction.
In the opposite case, it is evident for the person skilled in the sector that the positions θ1, θ2 will, instead, be the ones exactly specular with respect to the vertical axis of symmetry of the roll.
Consequently, the position θ1 will be beyond 270°, preferably between 360° and 270°, and the position θ2 will preferably be before 270°, even more preferably between 180° and 270°.
In this connection,
To return to
This configuration is advantageous in so far as it does not subject the semi-finished products to the stresses, prevalently bending stresses, to which the products that travel on the belt 206 of the machine of
Also this aspect contributes to guaranteeing an optimal quality of production.
With reference now to
For this purpose, the roll 12 has, along its circumference, radially projecting formations 12′ that follow one another according to a pitch that corresponds to the pitch with which the mould cavities 2′ follow one another on the lateral surface of the moulding roll 2.
During rotation of the roll, these projections move alternately into contact with the belt 6 and pull it each time against the moulding roll 2 in the points into which simultaneously respective mould cavities 2′ move.
The purpose of the above action is to ensure adhesion of the semi-finished products contained in the cavities 2′ to the belt 8.
In various preferred embodiments, as in the one illustrated, a second lobed roll 14 having a configuration corresponding to the roll 12 is associated to the belt 8, and is configured for exerting thereon an equivalent action of pressure at instants when it is released from the roll 12, the purpose being to keep the belt 8 constantly, throughout its perimeter, in one and the same condition of tension.
Of course, without prejudice to the principle of the invention, the details of construction and the embodiments may vary, even significantly, with respect to what has been illustrated herein purely by way of non-limiting example, without thereby departing from the scope of the invention, as is defined by the annexed claims.
Number | Date | Country | Kind |
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18166201.6 | Apr 2018 | EP | regional |