AUTOMATIC APPARATUS FOR DEPOSITING SAUCE ONTO PIZZA BASES OR

FOODSTUFFS

Technical Field The present invention relates generally to an automatic apparatus for depositing sauce onto pizza bases or foodstuffs, and more specifically to an automatic apparatus provided with a shower-like dispenser head which is able to deposit sauce, such as tomato sauce, onto stationary or moving pizza bases or foodstuffs that are carried on a conveyor device.

Background of the invention

Automatic devices for depositing sauce onto pizza bases or foodstuffs are known from the state of the art. When one wants to deposit sauce onto moving pizza bases or foodstuffs that are carried on a conveyor device it is convenient that the apparatus can avoid the sauce being spilled outside the pizza base or foodstuff and on the conveyor device, as this means a waste of sauce and results in dirtiness of the conveyor device.

The patent GB-A-2298776 discloses an apparatus for depositing sauce onto moving pizza bases while they are transported on a conveyor device. The apparatus includes a curtain-like dispenser head consisting of a sauce supply conduit transversally situated above the conveyor device, and a plurality of sauce dispensing nozzles arranged side by side to one another, forming a row alongside the supply conduit and in communication with it. Each nozzle is associated to a valve device comprising a plunger that is individually operated by pneumatic means in order to open or close the sauce passage from the supply conduit towards an inlet of the nozzle. The valve devices of the several nozzles are controlled by electronic control means that are synchronised with the advance movement of the pizza bases above the conveyor device so that they are individually opened and closed for depositing ejected sauce portions in parallel lines onto the pizza bases. The plunger of each valve device can be withdrawn after the ejection of a portion of a sauce dose in order to create a suction effect in the nozzle to stop the ejection of sauce from the nozzle in a quick and precise way. This apparatus has several drawbacks. On one hand, the device has a complex construction due to the large number of valves individually operated and controlled. On the other hand, it is difficult to assure an even distribution of the sauce along the outlet and through the several nozzles due to the relatively high viscosity of the sauce. The patent US RE 36178 EE1 describes an apparatus for depositing a precise quantity of sauce onto a pizza base. The apparatus comprises a shower-like dispenser

head that includes a body defining a sauce chamber. The mentioned body has a generally circular lower plate that can be set facing a pizza base and through which a plurality of sauce dispensing nozzles in communication with said chamber are arranged. The apparatus includes a dosing device configured and arranged to receive sauce from a sauce tank and to inject successive sauce doses to the chamber, so that each one of the injected doses is ejected as multiple portions through said nozzles and deposited onto one of the successive pizza bases being carried on a conveyor device. A diffuser plate provided with multiple bores is suspended inside the chamber to force the sauce from the dosing device to pass around and through the diffuser plate towards the nozzles in order to facilitate the most even possible distribution and diffusion of the sauce throughout the chamber. One drawback of this apparatus is that it does not comprise means to stop the sauce ejection though the nozzles in a quick and precise way at the end of each dosing process, which may result in imprecision in the dosage, difficulties in the synchronisation between the dispenser head and the conveyor device, and the risk of dropping sauce outside the pizza bases and on the conveyor device.

The document WO 00/00034 discloses an apparatus for depositing and spreading sauce on a pizza base, which includes a dispenser head comprising a body defining a sauce chamber. The mentioned body has a generally circular lower plate that can be set facing a pizza base, and through said lower plate a plurality of sauce dispensing nozzles in communication with said chamber are arranged. The apparatus includes a dosing device configured and arranged to receive sauce from a sauce tank and to inject successive sauce doses to the chamber to be deposited in the form of multiple portions ejected through said nozzles to successive pizza bases. The dispenser head further includes a porous plate situated below the lower plate forming an air chamber between them, and the sauce dispensing nozzles are arranged through the air chamber and corresponding openings in the porous plate. The air chamber has an inlet though which compressed air is introduced, and the compressed air is emitted through the pores of the porous plate to spread the ejected portions of sauce onto the pizza base. This process of depositing and spreading sauce requires a set amount of time, which is why depositing and spreading operations are carried out onto stationary pizza bases. Accordingly, this document does not meet the speed and accuracy requirements for depositing sauce onto moving pizza bases.

Summary of the invention One objective of the present invention is to provide an automatic apparatus for depositing sauce onto pizza bases or foodstuffs, which has a shower-like dispenser

head that is able to evenly eject successive doses of sauce, each one in the form of multiple ejected portions, in a quick, precise and reliable way, so that the dispenser head is able to deposit sauce in a uniform pattern onto either stationary or moving pizza bases or foodstuffs, which are generally carried on a conveyor device. The present invention contributes to achieve the previous and other objectives by providing an automatic apparatus for depositing sauce onto pizza bases or foodstuffs, of the type including at least a dispenser head comprising a body that defines a sauce chamber, said body having a lower plate that can be set facing a pizza base or foodstuff and a plurality of sauce dispensing nozzles arranged through said lower plate and in communication with said chamber, and a dosing device configured and arranged to receive sauce from a sauce tank and inject sauce into the chamber in successive doses to be ejected through said nozzles and deposited onto successive pizza bases or foodstuffs. The apparatus further includes a dividing plate for the purpose of dividing said chamber into an upper chamber region and a lower chamber region that are communicated by a plurality of through holes formed in said dividing plate, wherein said dosing device is arranged to dose sauce to said upper chamber region, and actuation means configured and arranged to impart a reciprocating movement to said dividing plate with respect to the body, or vice versa, between a first relative position, where the upper chamber region has an increased volume and said lower chamber region has a decreased volume, and a second relative position, where the upper chamber region has a decreased volume and the lower chamber region has an increased volume. Each one of said plurality of sauce dispensing nozzles includes a tubular element with an inner conduit, a lower portion inserted in a corresponding through hole formed in the lower plate of the chamber body, an outlet of said inner conduit at the end of said lower portion, and at least an inlet to the inner conduit arranged to be alternately closed and opened in communication with the lower chamber region as a result of said to-and-fro relative movement between the dividing plate and the body.

It is very important for the good operation of the head that no air pockets mixed within the sauce are present inside the chamber. To this end, the apparatus includes a purging device arranged in connexion to the upper chamber region to purge any air contained in the chamber when the chamber is first filled, or at any time considered to be necessary.

In one specific embodiment, each tubular element has a closed upper end attached to the dividing plate so that the tubular element moves therewith, while said lower portion is slidingly inserted into said through hole in the lower plate. In this case, the inlet of the tubular element is a lateral opening located in such a position as to be

- A - alternately closed by a wall of the through hole, when the body and the dividing plate are in said first relative position, and opened in communication with the lower chamber region when the body and the dividing plate are in said second relative position. According to an alternative embodiment, the lower portion of the tubular element is inserted and attached to the through hole in the lower plate, and, as a result, the tubular element moves therewith, while the tubular element has an upper portion slidingly inserted into a through hole in the dividing plate. The inlet of the inner conduit of the tubular element is a lateral opening located near a blind end of said upper portion of the tubular element in such a position that it is alternately closed by a wall of said through hole in the dividing plate when the body and the dividing plate are in said first relative position, and opened in communication with the lower chamber region when the body and the dividing plate are in said second relative position.

In any case, the inlets for accessing the inner conduit of the tubular elements are alternately opened to allow the passage of a sauce dose in the form of multiple portions that are ejected through the corresponding delivery openings, and closed to cease the ejection of the sauce dose. The apparatus includes electronic control means connected to the dosing device and to the actuation means for imparting the relative movements to carry out the injection of each dose of sauce to the upper chamber region while the inlet of the tubular element is, at least, partially opened. Preferably, said electronic control means are designed to carry out the injection of each sauce dose to the upper chamber region during the relative movement between the body and the dividing plate from the first relative position to the second relative position. The relative movements between the dividing plate and the body of the chamber result in an alternated sauce pumping effect in opposite directions between the upper and lower chamber regions though the through holes formed in said dividing plate, which makes the ejection quicker and its starting and stopping more accurate. Furthermore, the position of the inlet for acceding the inner conduit of each tubular element in relation to an upper port of the through hole of the lower plate or in relationship with a lower port of the through hole on the upper plate (depending on the embodiment) is such that, during the transition from the first relative position to the second relative position, and during the injection of the next sauce dose, a suction effect in the inner conduit of the tubular element though the inlet takes place. This suction effect makes the ejection stop even more sudden and accurate and avoids any sauce remaining inside the inner conduit of the tubular element dripping outside the pizza base or foodstuff and onto the conveyor device. The speed and accuracy in the ejection of each sauce dose allows for the apparatus of the present invention to deposit sauce onto moving pizza bases or

foodstuffs. To this end, the lower plate of the body is arranged over the trajectory of a row of pizza bases or foodstuffs that are continuously carried forward by a conveyor device, and the electronic control means are also in connexion with said conveyor device. The electronic control means are configured to dispense successive sauce doses in the form of multiple portions ejected from said dispenser head in advance with respect to the advance of the pizza bases or foodstuffs in order to make each sauce dose to be released and deposited in a predetermined position onto one of the pizza bases or foodstuffs. The apparatus of the present invention is obviously also suitable for use with a conveyor device which carries the pizza bases or foodstuffs forwards with intermittent stopping, in which case the ejection occurs when a pizza base or foodstuff stops under the dispenser head. Alternatively, the head can be installed on a movable part of a structure base operated to move back and forth in the direction of the movement of the conveyor device, and the ejection, at least partially, occurs during a time period in which the head movement follows the translation of a pizza base or foodstuff continuously carried forward by the conveyor device.

Brief Description of the Drawings

The previous and other features and advantages of the invention will be better understood from the following detailed description of some exemplary embodiments with reference to the enclosed drawings, where:

Fig. 1 is a cross-sectional schematic view of an automatic apparatus for depositing sauce onto pizza bases or foodstuffs according to an embodiment of the present invention;

Fig. 1 A is a lower view of a dispenser head as part of the apparatus of Fig. 1 ; Fig. 2 is a cross-sectional schematic view of the head showing a chamber body and a dividing plate in a first relative position;

Fig. 3 is a cross-sectional schematic view of the head showing the chamber body and the dividing plate in a second relative position;

Figs. 4 and 5 are enlarged detailed views showing the actuation of a tubular element according to one embodiment when the chamber body and the dividing plate are in said first and second relative positions, respectively; and

Figs. 6 and 7 are enlarged details showing the actuation of a tubular element according to another alternative embodiment when the chamber body and the dividing plate are in said first and second relative positions, respectively.

Detailed description of exemplary embodiments

With reference first to Fig. 1 , the automatic apparatus for depositing sauce onto pizza bases or foodstuffs includes, according to one embodiment, a dispenser head 1 , comprising a body 3 defining a chamber 2a, 2b for sauce S. said body 3 has a lower plate 3a positioned over the trajectory of a row of pizza bases or foodstuffs P that are carried forward on a conveyor device 13. Inside the aforementioned chamber 2a, 2b there is a dividing plate 7 dividing the chamber 2a, 2b into an upper chamber region 2a and a lower chamber region 2b, which are mutually communicated by a plurality of through holes 8 formed in said dividing plate 7. The dividing plate 7 is connected to a support 14 situated outside the chamber 2a, 2b by means of columns 14a inserted in a sliding manner through corresponding openings 15 formed in the upper wall of the body 3. Actuation means, such as, for example, a linear actuator 16, are arranged with their movable parts connected respectively to the body 3 and to said support 14 to impart a reciprocating relative movement between the dividing plate 7 and the body 3. This reciprocating movement is carried out between a first relative position (shown in Figs. 1 and 2), where the upper chamber region 2a has an increased volume and the lower chamber region 2b has a decreased volume, and a second relative position (shown in Fig. 3), where the upper chamber region 2a has a decreased volume and the lower chamber region 2b has an increased volume. A plurality of sauce dispensing nozzles 4 which are put in communication with the lower chamber region 2b at intervals as a result of the reciprocating relative movement are arranged through said lower plate 3a, as will be explained in more detail below.

The apparatus further includes a dosing device 5, such as, for example, a volumetric dosing device 26 operated by a linear actuator 19, which is configured and arranged in order to receive sauce S from a sauce tank 6 through a feeding pipe 20, and inject sauce S in successive doses to the upper chamber region 2a through an inlet conduit 21 . The apparatus includes electronic control means, which are in connection with the dosing device 5 and with the actuation means to carry out the injection of each sauce dose S to the upper chamber region 2a while the nozzles 4 are, at least partially, opened in communication with the lower chamber region 2b. Thus, each sauce dose S that is injected into the upper chamber region 2a by the dosing device 5 goes to the lower chamber region 2b through the through holes 8 in the dividing plate 7 and is ejected in the form of multiple portions S1 through the nozzles 4 and deposited onto one of the successive pizza bases or foodstuffs P, which are on the conveyor device 13. To eliminate any air pockets mixed with the sauce inside the chamber 2a, 2b, the apparatus includes a purging device 12, such as for example a valve 24 operated by an actuator

25, arranged in connexion with the upper chamber region 2a through an outlet conduit 22 to purge the air contained in the chamber 2a, 2b at the time the chamber 2a, 2b is initially filled or as considered necessary. The purging device 12 is in connection with the sauce tank 6 trough a return duct 23. During the normal operation of the apparatus, the valve 24 of the purging device 12 is closed.

In Fig. 1A a possible distribution of the nozzles 4 across the lower plate 3a and of the through holes 8 across the dividing plate 7 is shown. The shape of the head 1 is generally circular in accordance with the size of the pizza base to be coated with sauce, although for other foodstuffs the shape of the head may vary. The density of the nozzles 4 and of the through holes 8 will be selected as a general rule in function of the viscosity of the sauce and of the size of the dose. When the ejected sauce portions S1 impacts against the upper surface of the pizza base or foodstuff P they spread out to some extent forming spread out sauce portions S2. Depending on the density of nozzles 4 on the lower plate 3a and the viscosity of the sauce S, the spread out sauce portions S2 can remain isolated on the surface of the pizza base or foodstuff P or can merge together to form a substantially even sauce coating. The lower plate 3a can be attached to the rest of the body 3 by means of, for example, screws 27 and sealing joints can be provided where considered necessary. Although in the figures the lower plate as well as the rest of the body 3 are shown as being each one-piece part, it is also contemplated for each to be made up of several parts.

The operation of the dispenser head 1 is described now with reference to Figs. 2 and 3, with the actuation and constitution of the nozzles 4 being shown in greater detail in Figs. 4 and 5. In the embodiment shown in Figs. 1 to 5, each one of the sauce dispensing nozzles 4 includes a tubular element 9 that has a lower portion 9a inserted in a sliding manner in a corresponding through hole 10 in the lower plate 3a, and an upper portion 9b with an end attached to the dividing plate 7, for example by a threaded coupling in a corresponding blind hole 28 formed in the dividing plate 7 (Figs. 4 and 5). The tubular element 9 also has an inner conduit 9c, an outlet 1 1 a of said inner conduit 9c at the end of said lower portion 9a, and an inlet 1 1 b to the inner conduit 9c in the form of a lateral opening. The access to the inner conduit 9c at the end of the upper portion 9b of the tubular element 9 is closed off by the blind hole 28 in the dividing plate 7. The aforementioned inlet 1 1 b is in such a position that it is alternately closed by a wall of the through hole 10 in the lower plate 3a when the body 3 and the dividing plate 7 are in said first relative position (Figs. 2 and 4) and opened in communication with the lower chamber region 2b when the body 3 and the dividing plate 7 are in said second relative position (Figs. 3 and 5).

A complete cycle of a sauce dose S dispensation involves, for example, starting at the first relative position (Fig. 2), switching to the second relative position (Fig. 3) and returning to the first relative position (Fig. 2). In a time period during the cycle, while the inlets 1 1 b to the inner conduits 9c of the tubular elements 9 forming the nozzles 4 are opened, the dosing device 5 injects a sauce dose S that is ejected in the form of portions S1 through the outlets 1 1 b of the nozzles 4. The injection of the sauce dose S can be carried out while the body 3 and the dividing plate 7 are stopped in the second relative position (Fig. 3), or during the transition between the first and second relative positions, where the inlets 1 1 b are gradually opening, or during the transition between the first and second relative positions, where the inlets 1 1 b are gradually closing, or a combination of the first possibility with any of the second ones. Preferably, the electronic control means are configured to carry out the injection of each sauce dose S to the upper chamber region 2a during the relative movement between the body 3 and the dividing plate 7 from the first relative position to the second relative position. On the other hand, the positioning of the inlet 1 1 b of each nozzle 4 in relation to the upper port of said through hole 10 in the lower plate 3a is such that, during the transition from the first relative position to the second relative position, and at the start of the injection of the subsequent sauce dose S, a suction effect in the inner conduit 9c of the tubular element 9 is produced through the inlet 1 1 b, which stops the ejection of the previous sauce dose S in an sudden manner and prevents the sauce remaining in the inner conduit 9c of the tubular element 9 from dropping.

In Figs. 6 and 7 an alternative embodiment for the nozzles 4 is shown, according to which each nozzle 4 includes a tubular element 9 provided with an inner conduit 9c. Here the tubular element 9 has a lower portion 9a attached, for example by means of a threaded coupling, to a through hole 10 in the lower plate 3a and an upper portion 9b inserted in a sliding manner into a through hole 18 formed in the dividing plate 7. The tubular element 9 further has an outlet 1 1 a in the end of the lower portion 9a that opens to the exterior through the through hole 10 in the lower plate 3a and an inlet 1 1 b in the form of a lateral opening. One end of the upper portion 9b is blind in order to prevent access to the inner conduit 9c though the through hole 18 in the dividing plate 7. The inlet 1 1 b is in such a position that is alternately closed by a wall of said through hole 18 in the dividing plate 7, when the body 3 and the dividing plate 7 are in said first relative position (Fig. 6), and opened in communication with the lower chamber region 2b when the body 3 and the dividing plate 7 are in said second relative position (Fig. 7). With this alternative embodiment, the operation of the head 1 is similar to that previously described in relation to the embodiment shown in Figs. 1 to 5, and the aforementioned

suction effect is also produced as a function of the position of the inlet 1 1 b in relation to the lower port of the through hole 18 in the dividing plate 7.

Referring back to Fig. 1 , the apparatus of the present invention allows for an operative situation where the head 1 is supported on a base structure 17 with the lower plate 3a of the body 3 positioned above the trajectory of a row of pizza bases or foodstuffs P which are continuously moving forward along a conveyor device 13, and the electronic control means are also in connection with said conveyor device 13 to dispense successive sauce doses S in the form of multiple ejected portions S1 from the dispenser head 1 in a predetermined time in advance calculated so that each portion of sauce falls and is deposited onto one of the pizza bases or foodstuffs P in a predetermined position. Nevertheless, the apparatus of the present invention can also be used in other operative situations where the lower plate 3a of the body 3 of the head 1 is positioned above the trajectory of a row of pizza bases or foodstuffs P which are carried forwards with intermittent stop by the conveyor device 13. In this case, the electronic control means, which are further connected to the conveyor device 13, control the apparatus to dispense successive sauce dose S in the form of multiple ejected portions S1 from the dispenser head 1 in synchronism with the stops of the conveyor belt 13, so that each amount of sauce falls and is deposited onto one of the pizza bases or foodstuffs P in a predetermined position. It is also possible to equip the apparatus with means to make the head 1 move forward following the movement of the pizza bases or foodstuffs P during the ejection of the sauce dose and for make it to return to its original position before the next dispensing operation begins, or combinations of the previous possibilities.

It will be understood that, whatever the type of movement of the conveyor device is, it can be adapted to carry several parallel rows of pizza bases or foodstuffs P, in which case several heads 1 , similar to the one described above, will be supported in the base structure 17, each one having its lower plate 3a positioned above the trajectory of one of these parallel rows of pizza bases or foodstuffs P.

In the embodiment shown in Fig. 1 , the previously mentioned support 14 is attached to the base structure 17 (only symbolically depicted) so that the body 3 with the lower plate 3a moves with respect to the base structure 17 while the dividing plate 7 and the tubular elements 9 are stationary during the reciprocating relative movement between the dividing plate 7 and the body 3. In this way, the distance between the end of the lower portions 9a of the tubular elements 9, where the respective outlets 1 1c of the nozzles 4 are, remains at a constant height in relation to the surface of the conveyor device on which the pizza bases or foodstuffs P rest, which facilitates the adjustment of

the head so that it can deposit the sauce according to an even predetermined pattern. Otherwise, in an alternative embodiment (not shown), the body 3 and the lower plate 3a are attached to a base structure 17 so that the support 14 along with the dividing plate 7 and the tubular elements 9 move with respect to said base structure 17 while the body 3 and the lower plate 3a remain stationary during the reciprocating relative movement between the dividing plate 7 and the body 3.

Someone skilled in the art will be able to carry out modifications and variations from the exemplary embodiments shown and described without departing from the scope of the present invention as is defined in the appended claims.