The present invention relates to a machine for manufacturing puff-pastry of substantially circular form, which may be employed for preparing foodstuffs of various kinds, such as cakes of several types as well as pizzas.
Puff-pastries which are employed for such uses are generally of circular form and are obtained by lamination or flattening of a globoidal small mass of dough, which has been suitably prepared at a previous time, the lamination being obtained either through a manual operation or suitable known machines.
The mechanical manufacturing system is substantially carried out by laminating the pre-manufactured dough along two directions, which are at right angle each other.
The two lamination operations are generally obtained by two roll trains in which are disposed devices to ensure that the two lamination operations are effected along two directions which are orthogonal each other. The devices are able to submit the pre-manufactured dough, which is shaped with a nearly elliptical form at the outlet of the first roll train, to a suitable direction change or a rotation so that the second roll train acts on the dough in a direction which is orthogonal to the direction of the first lamination, so that finally a puff-pastry of substantially circular form may be obtained.
With reference to the system which has been utilized for obtaining the direction change, the pairs of lamination rolls may be disposed reciprocally parallel, or orthogonal or inclined in different manners as well as coplanar or disposed on different planes.
Several solutions have been proposed for obtaining the change in the lamination direction, however these solutions have given rise to various inconveniences and limitations.
For instance, in the machine described in Swiss Pat. No. 289,367 at the outlet of the first roll train the pre-manufactured dough is lodged on a horizontal shelf, from which it is successively manually pushed in to the second roll train, which in turn is arranged in an orthogonal relationship to the first one.
Clearly, the manual intervention requires a careful intervention of the operator and besides it restricts in a considerable manner the performances of the machine. U.S. Pat. No. 1,871,753 describes a machine like the former one, which however should be more efficient since it is provided with a transfer plate which pushes the pre-manufactured dough into the second roll train, wherein such plate is actuated with a reciprocating movement by means of a kinematic motion device which is interconnected to the driving unit of the roll trains.
Besides being mechanically complicated, this solution is also less reliable during operation.
In fact, particularly in the case in which the dough to be manufactured is somewhat soft, at the outlet of the first roll train the pre-manufactured dough may become deformed by the push action which has been produced by the transfer plate, and the pre-manufactured dough even may stick on the horizontal shelf, so that it is completely squashed by the motion of the plate, resulting in the dough being unusable.
U.S. Pat. Nos. 2,707,924; 3,792,948 and 3,883,283 describe solutions which employ elaborate systems, including conveyors which are disposed in different manners, to transfer the pre-manufactured dough from the first to the second roll train.
Clearly, these solutions are considerably complicated, encumbering and expensive.
On the contrary, solutions which are realized in a more simple manner are those described in U.S. Pat. No. 1,763,620 and French Pat. No. 7,617,715, in which at the outlet of the first roll train the pre-manufactured dough is passed over an inclined transfer plane, which is constituted by a fixed plate or a conveyor and during its movement it is subjected to a lateral action by a stopping element which causes the pre-manufactured dough to be rotated around itself. Still being simple, these solutions clearly do not ensure a steady and correct rotation of the pre-manufactured dough, so that the final result is always too approximate, unsteady and uncertain.
Still another simple but more rational solution is described in French Pat. No. 7,507,516, which is similar to the two just previously described. However, in this case rotation of the pre-manufactured dough obtained at the outlet of the first roll train is achieved by the application of a special oscillating device which is constituted either by a tray having two raised orthogonal edges only or by a square having two arms orthogonal each other, which tray or square are pivoted at their relevant angle on the transfer inclined plane and suitably counterweighted.
The pre-manufactured dough which slides over the inclined plane knocks against the transverse element of the tray or square, thus causing the latter to be rotated about its pivot. Consequently, also the premanufactured dough is rotated and inserted into the second roll train.
The tray or the equivalent square, as soon as the pre-manufactured dough has left it, returns in its starting position by the action of a counterweight or an equivalent return means.
An identical solution is also described in Italian patent application No. 83639 A/77.
Finally, Italian patent application No. 83410 A/81 describes a solution which is completely similar to the two last ones, but differs therefrom only in the fact that the two roll trains are not disposed parallel to each other, but rather at angled positions, and that it comprises a means for correcting the path of movement, which means is constituted by a rotating disc which projects from the sliding plane.
In this machine the roll trains are disposed inclined with respect to the horizontal plane, permitting in this manner a pre-manufactured dough obtained from kneadings and which is not soft to be deformed, due to its own weight, so that the final puff-pastry does not have the desired circular form.
The application of the means for correcting the movement path does not overcome such inconvenience nor does it provide any functional improvement, so that this means practically has ever been utilized.
The solution described in French patent No. 7,507,516 and therefore also the following equal solutions which have been described in Italian patent application Nos. 83639 A/77 and 83410 A/81 present remarkable functional inconveniences and limitations.
In fact, since the oscillating device has a fixed rotation point, any weight and/or dimensional change of the pre-manufactured dough causes it to be upset in an anticipated or delayed manner, with consequent imperfect positionings relative to the inlet of the second roll train. In addition, also the upsetting mode thereof may be changed due to several other accidental causes. A certain limited and sole regulation may be obtained by varying either the position of the counterweight acting on the tray, and therefore also the action thereof, or of the equivalent square. However, in practice this regulation is insufficient even in limited cases.