MARINI, Roberto (Via Provinciale Pratese 32, Agliana, I-51031, IT)
CAVAGNIS, Andrea (Riviera Tiso Camposampiero 7, Padova, I-35122, IT)
MORELLATO, Luciano (Via Martiri della Liberazione 35, Carmignano di Brenta, I-35010, IT)
MARINI, Roberto (Via Provinciale Pratese 32, Agliana, I-51031, IT)
CAVAGNIS, Andrea (Riviera Tiso Camposampiero 7, Padova, I-35122, IT)
| CLAIMS 1. An improved apparatus for packaging food products, said apparatus adapted to package groups of objects within a continuous tubular wrapper, said continuous tubular wrapper formed about said groups of objects by longitudinally welding a plastic film, said continuous tubular wrapper advancing on a conveyor along a conveying path while carrying inside said groups of objects that are arranged in sequence and spaced from each other at a predetermined distance, said apparatus comprising a welding element and cutting means, for welding and transversally cutting said tubular wrapper at said distance in order to create a succession of closed packs, each closed pack containing a respective group of objects, in particular long pasta such as spaghetti, said welding and cutting means comprising: - a slide that can reciprocate in a translation direction that is parallel to said conveying path; - a welding head that is connected to said slide and has two opposite jaws, which are adapted to carry out a cyclical opening/closing movement on said tubular wrapper when said slide moves in accordance with said tubular wrapper; - a jaw support that is adapted to cause each jaw to carry out said opening/closing movement on a closed trajectory, said jaw support comprising: - a first jaw support end that is adapted to move along said closed trajectory so that said jaws reach said tubular wrapper in a portion of said closed trajectory and follow said tubular wrapper for a predetermined portion of said conveying path to make a welding line and a transversal cut on said tubular wrapper, and - a second jaw support end that is pivotally connected to said reciprocating slide; - a welding element that is connected to each jaw support for making a welding line in a region of said gap; - a first and a second laminas that are associated to each jaw support, said laminas adapted to carry out a cyclical movement when said jaws carry out said closing movement between a wedge-like position and a spread apart position such that said welding element can move between said laminas when they are in said spread apart position, and such that said laminas clear said distance of any objects that are present along said distance; said device characterised in that - a first cam is provided on which a first arm slides and that is integral to said slide, said first cam adapted to guide a movement between said wedge-like position and said spread apart position of said first lamina, and - a second cam is provided on which a second arm slides and that is integral to said slide, said second cam adapted to guide a movement between said wedge-like position and said spread apart position of said second lamina. 2. An improved apparatus, according to claim 1 , wherein said cams are formed each by an input portion that causes said laminas to start moving towards said distanced position, a central portion, which increases the distance between said laminas and maintains such distance during the welding and cutting steps, and an output portion that causes a return movement towards said wedge-like position, the two cams being shifted from each other in the translation direction of said slide, in particular said central portion of said cams has a portion that is substantially parallel to said translation direction. 3. An improved apparatus, according to claims 1 and 2, wherein said first shaped arm is pivotally connected to said jaw support so that said first shaped arm rotates while keeping itself on a plane, said first shaped arm comprising: - an active end that is adapted to support said first lamina; - a sliding portion that is substantially at said active end and that is adapted to follow said first cam, according to the path of said cams; - a pivot end at which said first shaped arm is pivotally connected to a first end of a connecting rod, said connecting rod in turn connected to a second end to said second shaped arm. 4. An improved apparatus, according to claims 1 and 2, wherein said second shaped arm is pivotally connected to said jaw support so that said second shaped arm rotates while keeping itself on a plane, said second shaped arm comprising: - an active end that is adapted to support said second lamina; - a sliding portion that is substantially central and that is adapted to follow said second sliding cam, according to the path of said cams; - a pivot end at which said second shaped arm is pivotally connected to a second end of a connecting rod, said connecting rod in turn connected to a first end to said first shaped arm. 5. An improved apparatus, according to claim 3 and 4, wherein said connecting rod is adjustable in length for setting the relative distance between the end of said first and second shaped arm. 6. An improved apparatus, according to claim 1 , wherein said first and second shaped arms rotate with respect to said jaw support in a way biased by a respective elastic element, which keeps said laminas in said wedge-like position, and is in contrast with the movement towards said spread apart position that is caused by said sliding portions that move on the respective cams. 7. An improved apparatus, according to claim 1 , wherein said first and second shaped arms provide respectively at said sliding portion a bearing that is adapted to reduce friction as well as improving the precision and the efficiency of the movement on the corresponding first and second cams, in particular said bearings are adjustable according to a plurality of positions in a way that is suitable for calibrating the mutual distance between a first and a second laminas that are associated to said first jaw support and a first and a second laminas that are associated to said second jaw support, opposite to each other. 8. An improved apparatus, according to claim 1 , wherein said closed trajectory comprises a segment of circumference and a rectilinear segment, said rectilinear segment being substantially parallel to said conveying path. 9. An improved apparatus, according to claim 1 , wherein said closed trajectory is obtained through a coupling slide means which comprises: - a fixed guide that has the shape of said closed trajectory; - an engagement element that slides along said fixed guide, the engagement element being integral to the first end of said jaw support. 10.An improved apparatus, according to claim 1 , wherein a damping device is provided that is arranged integral to said jaw support and that is adapted to dampen, in said closing movement, a backward movement of said second shaped arm in order to reduce noise. |
IMPROVED APPARATUS FOR PACKAGING FOOD, IN PARTICULAR LONG
PASTA AND METHOD THEREFOR DESCRIPTION Field of the invention
The present invention relates to the industrial field of the automatic machines for packaging food products, in particular long pasta such as spaghetti, ribbon noodles, bucatini, etc. More precisely, the invention relates to a method and to an improved apparatus for packaging food products without defects of production.
Description of the technical problem
As well known, the step of packaging a set of food products into a wrapper, for example spaghetti, is done with automatic machines that are capable of putting into the wrapper a predetermined amount by weight of pasta. Then, each wrapper is closed, for example by thermowelding, creating a series of distinct packs that are delivered to a machine outlet zone in quick succession. In particular, machines exist that are continuously fed by pasta and comprise a conveyor belt which carries out repeatedly, at a predetermined rate, a welding step of a longitudinal end of the packs and sometimes the separation of consecutive packs. A technical problem arises that such machines are not capable of assuring that all the elements of a set of pasta is located in a correct position during the welding step and, consequently some pasta pieces stop at an intermediate location between two consecutive packs, causing a so-called "pinching", i.e. a faulty closure of the wrapper and therefore a product that cannot be preserved correctly and cannot be commercialized properly.
In the known machines, if the pasta pieces that stop accidentally in the above described intermediate location are only a few units, such elements can be broken by the action of spreading plates that approach the product from opposite sides in a welding zone. More precisely, the plates are at the beginning close to each other to form a wedge, such that they can successively spread apart from each other in order to cause the pasta pieces to fall far from the welding zone, thus freeing the intermediate location and allowing a correct welding.
In other machines, dedicated devices have been provided that sweep the welding zone from any possible pasta pieces that are not perfectly aligned with the pasta pieces set, thus reducing the risk of deforming the spreading plates as well as the welding head or the cutting member.
In particular, such devices comprise two plates, which are arranged at opposite sides with respect to a wrapping film, which by determined mechanisms carry out a distancing movement such that the spaghetti, which are present in the welding zone, are aligned in a correct position. Then, the thermowelding step is carried out that is, this way, not affected by the above described drawbacks.
There is however a technical problem concerning the mechanism that carries out and adjusts the alignment means. More in detail, this device uses resilient components that provide a correct alignment between the two corresponding distancing plates that are arranged at opposite sides with respect to the wrapping film. In particular, such components are calibrated and adjusted in order to cause the distancing plates to carry out the distancing movement and at the same time to follow the speed of the film in order not to delay the movement of the film in the production line while clearing the welding zone.
Such coordination of movements is rather difficult since the factors that affect the movement of the plates when approaching are many and, then, a resilient element or spring element that has appropriate features for this task is very complex. In fact, such resilient elements with time loose the original resilient features so that a change and/or adjustment of the apparatus is necessary that requires a stop of the production line.
Another drawback is that a variety of types of pasta need, in the production line, different adjustment of the above described distancing device in order to optimize the packaging time and speeding up the production line.
However, adjusting the resilient devices as described above requires a time consuming and difficult steps so that it is preferable to set the process with less precision to reduce the costs of production. Summary of the invention
It is therefore a feature of the invention to provide an improved apparatus for packaging food products, in particular long pasta that is easily adjustable with precision responsive to the kind of pasta and of the speed of the line production automatic in order to reduce the time and the costs of production.
It is a further feature of the present invention to provide an improved apparatus for packaging food products that improve the quality of the products and reduces the number of faulty packages.
It is also a feature of the present invention to provide an improved apparatus for packaging food products, in particular long pasta that is structurally easy and reliable with time.
These and other objects are achieved by an improved apparatus for packaging food products, said apparatus adapted to package groups of objects within a continuous tubular wrapper, said continuous tubular wrapper formed about said groups of objects by longitudinally welding a plastic film, said continuous tubular wrapper advancing on a conveyor along a conveying path while carrying inside said groups of objects that are arranged in sequence and spaced from each other at a predetermined distance, said apparatus comprising a welding element and cutting means, for welding and transversally cutting said tubular wrapper at said distance in order to create a succession of closed packs, each closed pack containing a respective group of objects, in particular long pasta such as spaghetti, said welding and cutting means which comprises:
- a slide that can reciprocate in a translation direction that is parallel to said conveying path;
- a welding head that is connected to said slide and has two opposite jaws, which are adapted to carry out a cyclical opening/closing movement on said tubular wrapper when said slide moves in accordance with said tubular wrapper; - a jaw support that is adapted to cause each jaw to carry out said opening/closing movement on a closed trajectory, said jaw support comprising: - a first jaw support end that is adapted to move along said closed trajectory so that said jaws reach said tubular wrapper in a portion of said closed trajectory and follow said tubular wrapper for a predetermined portion of said conveying path to make a welding line and a transversal cut on said tubular wrapper, and - a second jaw support end that is pivotally connected to said reciprocating slide;
- a welding element that is connected to each jaw support for making a welding line in a region of said gap;
- a first and a second laminas that are associated to each jaw support, said laminas adapted to carry out a cyclical movement when said jaws carry out said closing movement between a wedge-like position and a spread apart position such that said welding element can move between said laminas when they are in said spread apart position, and such that said laminas clear said distance of any objects that are present along said distance; said device characterised in that
- a first cam is provided on which a first arm slides and that is integral to said slide, said first cam adapted to guide a movement between said wedge-like position and said spread apart position of said first lamina, and
- a second cam is provided on which a second arm slides and that is integral to said slide, said second cam adapted to guide a movement between said wedge-like position and said spread apart position of said second lamina. In particular, said cams are formed each by an input portion that causes said laminas to start moving towards said distanced position, a central portion, which increases the distance between said laminas and maintains such distance during the welding and cutting steps, and an output portion that causes a return movement towards said wedge-like position, the two cams being shifted from each other in the translation direction of said slide.
Advantageously, said central portion of said cams has a portion that is substantially parallel to said translation direction. Advantageously, said first shaped arm is pivotally connected to said jaw support so that said first shaped arm rotates while keeping itself on a plane, said first shaped arm comprising:
- an active end that is adapted to support said first lamina; - a sliding portion that is substantially at said active end and that is adapted to follow said first cam, according to the path of said cams;
- a pivot end at which said first shaped arm is pivotally connected to a first end of a connecting rod, said connecting rod in turn connected to a second end to said second shaped arm. In particular, said second shaped arm is pivotally connected to said jaw support so that said second shaped arm rotates while keeping itself on a plane, said second shaped arm comprising:
- an active end that is adapted to support said second lamina;
- a sliding portion that is substantially central and that is adapted to follow said second sliding cam, according to the path of said cams;
- a pivot end at which said second shaped arm is pivotally connected to a second end of a connecting rod, said connecting rod in turn connected to a first end to said first shaped arm.
In particular, said connecting rod is adjustable in length for setting the relative distance between the end of said first and second shaped arm.
Advantageously, said first and second shaped arms rotate with respect to said jaw support in a way biased by a respective elastic element, which keeps said laminas in said wedge-like position, and is in contrast with the movement towards said spread apart position that is caused by said sliding portions that move on the respective cams.
Preferably, said first and second shaped arms provide respectively at said sliding portion a bearing that is suitable for reducing friction as well as improving the precision and the efficiency of the movement on the corresponding first and second cams, in particular said bearings are adjustable according to a plurality of positions in a way that is suitable for calibrating the mutual distance between a first and a second laminas that are associated to said first jaw support and a first and a second laminas that are associated to said second jaw support, opposite to each other. This way, it is possible to adjust, responsively to the kind of pasta that has to be packaged on the production line, the mutual distance between the couple of opposite laminas thus improving the efficiency and optimizing the production rate. In particular, the closed trajectory comprises a segment of circumference and a rectilinear segment, the rectilinear segment being substantially parallel and in a same direction as the conveying path.
Advantageously, the closed trajectory is obtained through a coupling slide means which comprises: - a fixed guide that has the shape of the closed trajectory;
- an engagement element that slides along the fixed guide, the engagement element being integral to the first end of the jaw support. In particular, a damping device is provided that is arranged integral to said jaw support and that is adapted to dampen, in said closing movement, a backward movement of said second shaped arm in order to reduce noise.
Brief description of the drawings.
The invention will be made clearer with the following description of some exemplary embodiments, exemplifying but not limitative, with reference to the attached drawings in which: - figure 1 shows the improved thermowelding and cutting apparatus for packaging continuously food products within a continuous tubular wrapper, according to the invention;
- figures from 2 to 8 depict a succession of steps that show in turn the movement of the couple of laminas that clear the food product from the welding zone and among which the welding element is put.
Description of preferred exemplary embodiments.
In the following description in Fig. 1 an improved apparatus is shown for packaging groups of objects consisting of food products such as long pasta, which is put within a continuous tubular wrapper 6 that is made starting from a longitudinally welded film of plastic material. In particular, tubular wrapper 6 slides on a conveyor belt 30 along a conveying path, according to arrow 8, while carrying inside the food products that are arranged in sequence and spaced from each other at a predetermined distance 80. Functionally, the device comprises a welding element and cutting means, for welding and transversally cutting tubular wrapper 6 at a distance 80 in order to form a succession of closed tubular packs 7 containing each a respective unit for objects, in particular spaghetti.
With reference always to Fig. 1 such a device, which is depicted with one part with a continuous line and the opposite part with a dotted line, comprises a slide 100 that can reciprocate in a translation direction 90 and a welding head with two opposite jaws, respectively indicated as 1 and 2, that are adapted to carry out a cyclical opening/closing movement on tubular wrapper 6 when slide 100 moves in accordance with the tubular wrapper. In particular, each jaw 1 and 2 comprises a jaw support 3/3' with a welding element 5/5' that is adapted to move on a closed trajectory (not shown) in order to reach in a portion of the trajectory tubular wrapper 6, to follow it for a predetermined travel along the conveying path and to carry out the welding and cutting steps. More precisely, jaw support 3/3' has a second end 4/4' that is pivotally connected to slide 100, such that jaws 1 and 2, for each cycle of slide 100, carry out a translation integrally to slide 100 and a rotation about a respective pivot point 4/4'. In particular, the closed trajectory comprises a segment of circumference and a rectilinear segment that is substantially parallel to the conveying path and is obtained through a coupling slide means comprising a fixed guide 40 having the shape of the closed trajectory and an engagement element that slides (not shown) along the fixed guide 40 integral to the first end of jaw support 3, described then in detail.
In addition, the packaging device comprises a welding part 51/51 ' that is connected to each jaw support 3/3' and that is adapted to melt a portion of wrapper 6 at a distance 80 in order to weld and to cut it. This welding and cutting step is assisted by the motion of a first 11 and a second 12 laminas that are associated to jaw support 3 an that are adapted to move, when jaw 1 carries out the closing movement, between a wedge-like position B (as visible in Fig. 5) and a spread apart position A (visible in Fig. 1 and 8) to allow the movement of welding element 51 and in the meantime releasing distance 80 from the pasta present in it.
According to the invention, then the movement between wedge-like position B and spread apart position an of first lamina 11 is guided, for a part of the closed trajectory, by a first fixed cam 60 on which a first shaped arm 20 slides that is integral to first lamina 11.
In parallel, the movement between wedge-like position B and spread apart position an of second lamina 12 is guided, for a part of the closed trajectory, by a second cam 70 on which a second shaped arm 10 slides that is integral to second lamina 12. As shown in Fig. 2, cams 60 and 70 are formed respectively by a respective input portion 61/71 , which begins the motion of laminas 11 and 12 towards the spread apart position, a central portion 62/72, which increases the distance between the laminas and maintains such distance during the welding and cutting steps, and an output portion 63/73 that causes a return movement towards the wedge-like position of the laminas. Structurally, the two cams 60 and 70 are shifted from each other along translating direction 90 of slide 100 and have central portions 62 and 72 that are substantially parallel to the translation plane of belt 30, the latter diagrammatically shown in the figure by a dotted line. Figure 3 shows more clearly first shaped arm 20 as pivotally connected to jaw support 3 according to a pivot point 21 about which rotates while keeping itself on a plane. In particular, first shaped arm 20 comprises: an active end 22, on which first lamina 11 is mounted, a sliding portion 23, which is arranged near the active end 22 that follows the first sliding cam 60 along the above described portions 61 , 62 and 63, and a pivot end 24, at which first shaped arm 20 is pivotally connected to a first end 25 of a connecting rod 26. The latter is in turn connected to a second end 27 of second shaped arm 10.
In analogy, second shaped arm 10, which is pivotally connected to jaw support 3, rotates about a pivot point 15 while keeping itself on a plane, and comprises: an active end 13 on which second lamina 12 is mounted, a central sliding portion 14, which is adapted to follow second sliding cam 70, and a pivot end 16 at which shaped arm 10 is pivotally connected to second end 27 of connecting rod 26. In particular, connecting rod 26 is adjustable in length for setting the relative distance between ends 24 and 16 of first shaped arm 20 and second shaped arm 10.
In the present exemplary embodiment, first shaped arm 20 and second shaped arm 10 provide, at sliding portions 23 and 14, a bearing 31 that moves on cams 60 and 70, thus reducing friction and improving the precision and the efficiency of the motion. In particular, bearing 31 is adjustable according to a plurality of positions in a way that is suitable for calibrating the mutual distance between first lamina 11 and second lamina 12, which are associated with first jaw support 3 and, a first lamina 11' and a second lamina 12', which are associated with jaw support 3' opposite to each other (as shown in Fig. 1 ). This way, it is possible to adjust, responsively to the kind of pasta that has to be packaged on the production line, the mutual distance between the couple of opposite laminas 11/11 ' and 12/12', thus improving the efficiency and optimizing the production rate. Always in a advantageous way, first shaped arm 20 and second shaped arm 10 are biased by a respective elastic element, which keeps laminas 11 and 12 in the wedge-like position B, and is in contrast with the movement towards spread apart position A that is caused by sliding portions 23 and 14 that move on the respective cams. Figures from 1 to 8 show in turn the relative movement of shaped arms
10 and 20 that guide laminas 11 and 12 between wedge-like position B and spread apart position A. In particular, Fig. 1 shows the step where the two laminas 11 and 12 are completely spread apart, position A, near the wrapper, and welding element 51 welds them running through them. Figs. 2, 3 and 4 show the following cyclic steps according to which the two laminas 11 and 12 withdraw to wedge configuration B distant from wrapper 6 for then carrying out, as shown in Figs. 5, 6, 7 and 8, a following approaching movement towards the sliding plane of the wrapper in order to clear the welding zone. In the figures the moment is shown where sliding portions 23 and 14, which are equipped with bearing 31 , slide on the central portions of the respective cams 60 and 70, thus progressively causing laminas 11 and 12 to spread apart, and welding element 51 to move in order to weld tubular wrapper 6 at distance 80. In addition, as shown in the figures and, in particular, in Fig. 4, a damping device is provided that is 95 arranged integral to jaw support 3 and that is adapted to dampen, when closing movement, a backward movement second shaped arm 10 in order to reduce noise.
The packaging device, according to the invention, allows then to optimize the process for packaging pasta responsive to the parameters of the production line in order to reduce the costs and the processing time. In addition, the production line responsive to the kind of pasta that has to be packaged can be adjusted the problems are solved of adjustment and maintenance that affect the known devices. The foregoing description of a specific embodiment will so fully reveal the invention according to the conceptual point of view, so that others, by applying current knowledge, will be able to modify and/or adapt for various applications such an embodiment without further research and without parting from the invention, and it is therefore to be understood that such adaptations and modifications will have to be considered as equivalent to the specific embodiment. The means and the materials to realise the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.