Abstract:
A conveyor of leaves and other products on a belt for laying the same products as a single layer, includes at least a perforated collection belt, at least a suction hood having a surface provided with holes for passage of air flow, an air suction device coupled to the hood, and dragging elements for the collection belt. The collection belt slides by the dragging elements along the perforated surface of the suction hood. The suction device generates an air flow both through the holes of the surface of the suction hood, and through the holes of the collection belt, allowing the coupling on the collection belt of a single layer of the leaves and other products due to their passage close to the collection belt.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a conveyor of leaves and other products on a belt for laying the same products as a single layer. 
   More specifically, the invention concerns a device allowing to lay on a belt leaves and other products for feeding purposes, so as to make it easier and faster possible transportation, lifting, cleaning, washing, drying, ecc. 
   At present, it exists the needing in industrial processes to convey leaf products such as salads, lettuce, radicchio, spinaches and other food products, toward the transformation lines according an ordered mode, in order to simplify the working and/or packaging. 
   In fact, said products are generally provided loosely or within bags or tanks to the transformation industries by stores or directly from the fields. 
   First working step usually provides removal of external foreign bodies and washing of the products suitable for use. 
   During this step, it arises the needing of uniformly distributing the product, also to more efficiently carry out the cleaning and visual choice operations. 
   In view of the above, it is well evident the needing of having at disposal a device as suggested by the present invention, allowing to collect leaf product from a conveyor belt on which it is loosely provided to transfer the same on another belt or transportation device, thus realising a single product layer. 
   SUMMARY OF THE INVENTION 
   In this context it is included the solution suggested according to the present invention. 
   It is therefore specific object of the present invention a conveyor of leaves and other products on a belt for laying the same products as a single layer, characterised in that it comprises at least a perforated collection belt, at least a suction hood having a surface provided with holes for passage of air flow, an air suction device coupled with said hood, and dragging means for said at least a collection belt, said collection belt sliding by said dragging means along said perforated surface of said suction hood, said suction device generating an air flow both through said holes of said surface of said at least a suction cap, and through said holes of said at least a collection belt, allowing the coupling on said at least a collection belt of a single layer of said leaves and other products due to their passage close to said at least a collection belt. 
   Still according to the invention, said conveyor can provide a slidable belt to carry said leaves and other products close to said at least a collection belt. 
   Preferably, according to the invention, said slidable belt can be provided under said at least a collection belt. 
   Furthermore, according to the invention, said slidable belt is provided on a support structure. 
   Preferably, according to the invention, the perforated surface of said suction hood can be a curved surface. 
   Always according to the invention, said suction hood can comprise a belt for collecting impurities, said belt having holes with sizes lower than the sizes of the holes of said at least a collection belt. 
   Still according to the invention, said impurity collection belt can slide inside and parallel with respect to said at least a collection belt, allowing filtering impurities present in said laves and other products. 
   Always according to the invention, said impurity collection belt can place said impurities within a container. 
   Furthermore, according to the invention, said conveyor can provide means for washing said leaves and other products. 
   Preferably, according to the invention, said means for washing said leaves and other products can be provided above and/or under said at least a collection belt. 
   Still according to the invention, said conveyor can comprise a space for collecting water used for washing said leaves and other products. 
   Always according to the invention, said conveyor can comprise means for drying said leaves and other products. 
   Preferably, according to the invention, said mans for drying said leaves and other products can be provided on said at least a collection belt. 
   Furthermore, according to the invention, said drying means can comprise an air suction device. 
   Still according to the invention, said conveyor can comprise a first and a second collection belt section. 
   Always according to the invention, said first and a second collection belt section can be superimposed in such a way that said first collection belt section couples with a first side of said leaves and other products, and said second collection belt section couples with the other side of said leaves and other products. 
   Still according to the invention, air flow for coupling with said first and a second collection belt section can dry said leaves and other products on both sides. 
   Preferably, according to the invention, said two conveyor belts can be provided vertically. 
   Furthermore, according to the invention, said conveyor can comprise a space for collection of said leaves and other products taken from said collection belt. 
   Preferably, according to the invention, said air suction device can be a pump or a fan. 
   Still according to the invention, said leaves and other products collected by said collection belt can be brought again close said at last a collection belt. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be now described, for illustrative but not limitative purposes, according to its preferred embodiments, with particular reference to the figures of the enclosed drawings, wherein: 
       FIG. 1  shows a lateral view of a first embodiment of a device for conveying leaves and other products on a belt with a single layer distribution according to the invention; 
       FIG. 2  is a top view of the conveying device of  FIG. 1 ; 
       FIG. 3  shows a lateral view of a second embodiment of a conveying device according to the invention; 
       FIG. 4  is a top view of the conveying device of  FIG. 3 ; 
       FIG. 5  shows a lateral view of a third embodiment of a conveying device according to the invention; 
       FIG. 6  shows a lateral view of a fourth embodiment of a conveying device according to the invention; 
       FIG. 7  is a further lateral view of the conveying device of  FIG. 6 ; 
       FIG. 8  shows a lateral view of a fifth embodiment of a conveying device according to the invention; 
       FIG. 9  is a further lateral view of the conveying device of  FIG. 8 ; and 
       FIG. 10  is a perspective view of the suction hood. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Making reference to  FIGS. 1 and 2 , it can be observed a conveyor  1 , mainly comprised of a conveyor belt  2  and of the collection belt  3 . Conveyor belt  2  is provided under the collection belt  3 . On one end of the conveyor belt  2 , product, i.e. leaves or other product, is charged in disorder. Said product  4  is thus dragged on the other end of the conveyor belt  2  rotating according to the direction indicated by arrow A, by the drive shafts  5  and  5 ′. 
   Collection belt  3 , that is substantially comprised of a large hole network, slides above a suction hood  6  (shown in detail in  FIG. 8 ), providing holes on the surface. Collection belt  3  slides on said suction hood  6  by a shaft  7  fixed on a support  8  according to the rotation direction B. 
   Once the product  4  arrives close the end of the conveyor belt  2 , is sucked by the suction hood  6  and adhered to the collection belt  3 . Vacuum is created between the suction hood  6  and the conveyor belt  3 , thanks to an air suction pump  9 . thus, in correspondence of the suction hood  6  a zone is realised keeping the product  4  adhering to the collection belt  3  while it slides, thanks to the negative pressure on the surface of said collection belt  3 . 
   Consequently, product lays in such a way to realise a single layer on the collection belt  3 . Further, it is also possible to obtain a product drying effect, thanks to the air flow to which it is subjected. 
   Finally, it can be noted that the conveyor  1 , in the embodiment described, is placed on a support  10 , while the conveyor belt  2  and the collection belt  3  are driven by motors  19  and  20 . 
     FIGS. 3 and 4  show an embodiment of the conveyor  1 , providing also the feature of separating, insulating and ejecting impurities that can be present in the product  4 . 
   As it is clear from the enclosed figures, it can be noted that the result is obtained by a modification of the suction hood  6 , providing a collection belt  11  under the collection belt  3 , said belt  11  having a filtering grain finer than that of said collection belt  3 , due to the negative pressure induced by the air flow by the suction pump  9  on the suction hood  6 , possible residual matter present in product  4  are collected and maintained adhering on the collection belt  11 . 
   Collection belts  3  and  11  rotate parallel to each other according to direction of arrow B and impurities are brought in a suitable container  12  sucked and ejected by a fan  13 . 
   Product  4 , that is placed as a single layer and depurated from the possible impurities is, in this embodiment, collected in a further collection belt  14  and driven by drive shafts  15  and  15 ′ and a motor  16 . Instead, product  4  that is not sucked and placed on the collection belt  3 , continues flowing until the end of the conveyor belt, accumulated within a container  18 , and thus inserted again at the beginning of the circuit of the conveyor belt  2 , to be placed as a single layer. 
     FIG. 5  shows a conveyor  1 , equivalent to the conveyor of  FIG. 1 , provided with the further functions of washing and drying the product  4 . 
   Particularly, once the product  4  has been placed as a single layer on the collection belt  3 , it is made passing through a washing device  31 , subjecting the same to a series of water jets from above and from bass. Washing water is then collected within a suitable space  22 . 
   Finally, product  4  is strook by a further air flow, directed downward, induced by the pump  21 . Collection belt  3  slides between the suction hood  6  and the shafts  7 ,  7 ′,  7 ″ and  7 ′″, in such a way to create a space within which said space  22  can be provided. 
     FIGS. 6 and 7  show an alternative embodiment of the conveyor  1 , allowing the drying of the product  4  on both sides. 
   Particularly, once the product  4  has been placed as a single layer on the collection belt  3 , it is made passing through a washing device  31 , subjecting the same to a series of water jets from above and from below. Washing water is then collected within a suitable space  22 . 
   Observing the figures in detail, it can be noted that product  4  is taken from a hopper  23  directly from the vertical collection belt  3 , sliding on the suction hood  6 . Air flow, generated by the pump  9 , directed on the product  4 , allows its drying on the first side. Product  4  is then laid down on another collection belt  24 , in this case too a vertical belt, on which it is kept thanks to a further suction hood  25  and to the air flow generated by the latter. 
   Product  4  is now placed as a single layer on the collection belt  24 , but rests on side opposite to the side on which it was rested while flowing on the collection belt  3 . In this way, flow generated by the suction hood  25  allows drying of the other side of product  4 . 
   Finally, product  4 , dried on both sides and placed as a single layer, can be placed on a new conveyor belt or visually inspected and/or introduced within a container  26 , as in  FIG. 6 . 
     FIGS. 8 and 9  show an alternative embodiment of the conveyor  1 , allowing the ejection of foreign matter from product  4  by a double filtering. Particularly, product  4 , placed as single layer on the collection belt  3  by pressure generated by the air flow from pump  9 , is then distributed on the collection belt  3 ′, making the heavier foreign matter falling. Air flows on the collection belts  3 ,  3 ′ are obtained by the suction hoods  6 ,  6 ′. From the collection belt  3 ′, product  4  passes to a further conveyor belt  32 , that, vibrating, allow a homogeneous distribution of the product  4  on the surface of the same belt. Thus product is again collected by a collection belt  33 , allowing a further filtering of the product, avoiding lifting residual impurities such as insects or little woods. Lifting occurs by the pressure from the pump  34  through the suction hood  35 . 
   Collection belt  33 , providing sloped sides, transports the product up to a collection belt  36  on which it falls by gravity, not being provided any air flow in the area where belts are superimposed. 
   Finally,  FIG. 10  shows the suction hood  6 . particularly, it can be seen surface  27  on which conveyor belt  3  or  24  slides, and on which air suction holes  28  are realised, said air being sucked within the tube  29 . air flow is generated by the pump  9  or by a fan inserted within the cavity. 
   On the basis of the previous specification, it can be observed that the basic feature is that of creating a depression on a conveyor belt so as to make the leaf product adhering and placing the same as a single layer. 
   Present invention has the advantage of making it possible to have the product ready for complex operations thanks to its more precise positioning, and at the same time to be able to simply add the functions of filtering impurities and drying the product. 
   Furthermore, by the present invention, product can be also lifted according to a vertical direction, maintaining a continuous and according to a single layer disposition feeding of the product. In fact, positioning of the product according to a single layer allows to ease their inspection and their eventual analyses by optical selection devices. 
   Another advantage of the invention is that of filtering both foreign matter with large sizes and weight, and sand particles and/or insects by suction. 
   Possibility of implementing the device according to vertical orientation allows a remarkable saving of space or a better adaptability to already existing lines. 
   Finally, product can be cooled and/or subjected to treatment during its transportation and/or lifting. 
   The present invention has been described for illustrative but not limitative purposes, according to its preferred embodiments, but it is to be understood that modifications and/or changes can be introduced by those skilled in the art without departing from the relevant scope as defined in the enclosed claims.