Method for thinning food dough, mechanical apparatus for implementing the method, and the food dough produced according the method.

The invention relates to a process for thinning food dough, or for stretching elongated food dough elements.

More precisely, the present invention also relates to a mechanical apparatus for implementing the method for stretching a block of dough into a thinned form, to which the following description explicitly refers, without for this reason excluding a broader application of the invention.

In the following description and in the claims, the term "food dough" relates to a puff pastry in pieces of a defined length, or food dough in continuous sheet form, sheet pastry, and the term "elongate dough elements" indicates any elongate form, such as the breadstick or whatsoever similar dough element .

In the food industry production processes are known and have long been used which for increasing end-product quality for the consumer, both regarding dietary considerations and for commercial reasons, from the point of view of novelty and appearance .

As operators in the sector well know, great importance is attributed to the handling of dough and in particular the thinness of food dough obtained by using machines, or mechanical apparatuses to implement automated and extremely reliable production processes.

It has been demonstrated that the thinner food dough is, the better are its features during preparation of the product for cooking, therefore the mechanical stretching actions on the food dough play a fundamental role in the quality of the final product.

Not all products made out of food dough brought on the market are of top quality as regards as softness and friability. Nowadays the requirements of the different consumer communities, or the various industrial trends in the production of foodstuffs made of food dough, require a vast

assortment of quality products providing good organoleptic quality, and last but certainly no less important, reasonable costs .

For this reason, producers and marketers of food dough products are trying to provide a large-scale supply of soft, friable food dough products that while offering high dietetic and organoleptic quality are also cheap.

To achieve an abundant supply of high quality, low cost food dough products, transformations are necessary to produce the thinnest food dough possible.

In fact, increasing the thinness of food dough, the product becomes impermeable to the steam formed from the water during cooking, so that a steam pressure is exerted on the internal layers of the product, which under such a pressure expands, attaining adequate volume and becoming agreeably soft.

For some time now, operators in the sector have been trying to improve the quality of food dough, in particular from the standpoint of the lightness and volume of the product after cooking. An object of the invention is to provide a process for thinning food dough by means of an apparatus combined with the output of food dough producing machines, in order to automatically make the food dough as thin as required for giving to the product the lightness and softness appreciated by consumers .

A further object is to ensure that the apparatus operates in a substantially continuous way and with a mechanical action, thus making the apparatus highly productive and particularly suitable for functioning within production plants. It is also within the scope of the object to provide a highly reliable and functionally efficient apparatus that is relatively simple and economically advantageous to use. A further object of the invention is to make the apparatus adaptable, through simple mechanical adjustments, to handle any variation whatsoever to the thinness of the food dough, so that during operation absolutely no operators assigned to

the apparatus are required.

The apparatus functions entirely mechanically implementing an advantageously continuous stretching cycle and does not requires stops or positioning the food dough between the inlet and the outlet of the apparatus.

A further object, no less important than those mentioned above, is that the apparatus should function with extremely low energy consumption. The object of the invention is therefore to provide a method and a mechanical apparatus overcoming all the drawbacks and disadvantages connected with the systems of the prior art. These aims and more besides are all attained by the present invention, which comprises a method for thinning food dough, or for stretching elongated food dough elements, the method comprising, in sequence, the following operating phases: gripping and progressively continuously grasping at least the two transversal edges of the food dough continuously advancing out from the laminating or preparation unit, said transversal gripping lines being equally distanced one from another in order to stretch substantially equally wide portions of the food dough progressively advancing along the stretching direction; progressively and constantly diverging the transversal gripping lines during the advance motion of the food dough so as to continuously extend, stretch and widen the transversal dimensions of the food dough, said diverging of the transversal gripping lines of the advancing food dough being reciprocally adjustable with constant angular widths that are preset according to the type of thinned food dough to be obtained; continuously vibrating the transversal gripping portions of the food dough, with oscillations adjustable in amplitude and frequency in order to substantially uniformly distribute the stretching action due to the progressive diverging, said continuous vibrating being activated both by flexible elastic elements interposed between the support structures, and by an

external vibration unit that transmits vibrating impulses to the support structures which impulses are adjustable according to the type of food dough to be thinned.

In a preferred embodiment the method enables the food dough to be gripped along continuous gripping lines with continuous contact between the food dough and the gripping lines, or along tracts of finite length, or along successive or alternating points.

In a further embodiment of the invention, the method allows to continuously adjust the vibrations by varying the preload on the elastic elements, which thus vibrate with variable elastic rigidities and elastic moduli.

A mechanical apparatus for thinning food dough, or for stretching elongated food dough elements comprises: - a base structure including a driving shaft on which drive pulleys are keyed, the drive pulleys cooperating, via flexible elements, with pulleys keyed onto a driven shaft; an over-structure coupled both with shafts and with pulleys and with pressing rollers so as to exert a pressing action on flexible elements exerting a stable gripping action on the food dough to be thinned; a vibrating system having elastic elements and in case at least an external vibrating unit.

In an embodiment, the mechanical apparatus comprises belt flexible elements preferably trapezoidally shaped, or similar belts with a circular section, arranged to grip and draw while gripping the food dough in the advance direction.

In a further embodiment the mechanical apparatus of the invention comprises flexible elements having, on the external gripping part thereof, protrusions shaped as tracts of finite length, or as points for gripping the food dough at tracts or successive or alternating points thereof.

The invention also comprises the thinned food dough, in particular pieces or sheets of thin food dough, stretched by thinning sliding in a thinning direction which is transversal to the advance direction of the food dough , the food dough

being micrometrically tensioned and stretched at every point of its surface without splitting or lacerations, and produced according to the method and using the mechanical apparatus described above. The invention will be better described in detail below with reference to the embodiment illustrated schematically in figures of the accompanying tables of drawings, which illustrate the characteristics of the invention, in which all the drawings attached, and the description thereof, correspond to a preferred embodiment in order to make its implementation more understandable.

However, the protection sought shall include all possible variations of the reciprocal positions of the elements and consequent simplifications which might derive therefrom, and all the constructive variants included in the general idea, as illustrated in the drawings attached and in which: Figure 1 is a schematic side view of the mechanical apparatus of the invention which shows the structure for stretching and thinning the food dough and also schematically shows the lamination or preparation unit, and the conveyor belts for advancing the food dough into, and out of, the thinning structure;

Figure 2 is a schematic side view showing the base structure assembled with the drive shaft, on which drive shaft the drive pulleys are keyed; the drive pulleys cooperate, via the flexible elements, with the return pulleys; figure 2 also illustrates the over-structure coupled with a plurality of shafts onto which shafts are keyed pulleys and pressure rollers exerting a pressing action on the flexible elements in order to obtain a constant and stable gripping action on the food dough;

Figure 3 is a schematic side view similar to Figure 2 showing the food dough at the inlet and outlet of the mechanical apparatus for gripping and thinning; Figure 4 is a schematic side view as that in Figure 2 showing a vibrating system having a plurality of elastic elements and

a plurality of external vibrating units.

In the figures, corresponding parts, or parts with the same functions, are for simplicity's sake indicated with identical references . Moreover, to clarify the whole, the devices and mechanisms which operate in reciprocal cooperation with the mechanical apparatus of the invention are not illustrated in the figures, and their functions are not described, since they are already known, and also because they are not necessary for an understanding the functioning of the invention.

Thus, for example, the driving motors for driving the conveyor belts and the preparation unit of the food dough and moreover, consequently, the particulars of the advancing circuits are not shown and described, since there are various different ways for carrying out them, all of known type. In the attached drawings:

1 is a portion of food dough conveyed by the belt 3 to the preparation or lamination unit 5; 2 is the conveyor belt for conveying the food dough 7 coming out from the preparation unit 5 in pieces, or as a continuous sheet; 4 is the output conveyor belt for conveying the food dough 9 thinned and stretched coming out from the apparatus according to the invention, in the advance direction 23; 8 is the support frame for supporting both the base structure 28 and the over- structure 29; 28 is a base structure assembled with the motor 10 and the relative drive shaft 20 onto which the drive pulleys 16 are keyed, which drive pulleys 16 cooperate via the flexible elements 18 with the pulleys 16 keyed on the driven shaft 22; 29 is a over-structure coupled to both the shafts 14 and 24, on which the pulleys 21 are keyed, and to the shafts 17 onto which the pressure rollers 11 are keyed which exert a pressing action on the flexible elements 19; 15 is a return geared motor provided between the motor 10 and the drive shaft 20; 12 is the support frame of the conveyor belt 4; 25 are helicoidal spring elastic elements which generate oscillatory and longitudinal elastic impulses; 26

are helicoidal spring elastic elements which generate transversal oscillatory elastic impulses; 27 are helicoidal spring elastic elements which generate vertical oscillatory elastic impulses; 13 is an electromechanical or electromagnetic vibrating unit, provided with electrical supply cables 30 of a known type, which vibrating unit 13 transmits adjustable exciting impulses to generate oscillations having frequency and amplitude values according to the type of food dough 9 to be thinned. The functioning of the mechanical apparatus of the invention, highlighted in the tables of the figures of the drawings attached, is easily understood, since the invention is extremely simple and is moreover easy to produce, apply and use . The production line for thinned food dough 9 comprises, between the lamination unit and the output conveyor belt 4, the mechanical apparatus according to the invention. The operator assigned to the production line, on the basis of the type of food dough and the thinness of the food dough to be obtained and the parameters of the production process, decides and sets the degree of divergence of the gripping lines 19 and 18 by varying the angular width using crank mechanisms of a known type which translate the pulleys 16 and 21 along the driven shafts 22 and 24. The pulleys 16 and 21 translate in perfectly and substantially synchronously, distancing from or bringing nearer to one another in equal measure.

The operator assigned to the line also sets the vertical distance between the base structure 28 and the over-structure 29 to adjust the gripping pressure exerted by the flexible elements 18 and 19 on the infeeding food dough 7 and on the outfeeding food dough 9.

Having carried out the adjustments, the operator blocks the various adjusting levers and cranks in the desired operating positions.

The motor unit 10 and 15 is activated and the conveyor belts

2, 4 and 6 are activated together with the lamination unit 5 and it is activated also the belt 3 which infeeds the portion of food dough 1 from a portioning unit, which is not illustrated since it is well known. In its one-directional advance the food dough 7 is gripped by the flexible elements 18 and 19 which draw and stretch the coming out food dough in to the preset thickness 9 and without lacerations, since the stretching is micrometrically distributed by the vibrating system shown in Figure 4. Modifications may be provided and, therefore, the elements and the devices described and illustrated may be replaced by other equivalent elements and devices, without going beyond the inventive idea as claimed below. The terminology adopted, for example "base" and "over- positioned", is used in the description and/or in the claims only to describe the relation of certain elements with regard to others when the mechanical apparatus is in its normal operating position, and must not be interpreted as limiting to this precise position.