ES2667703T3 - Sealing unit for a vertical flow packaging machine for short pasta - Google Patents

Abstract

Sealing unit (1) that can be fixed to a frame (25) of a vertical flow packaging machine (100) for short pulp, said shutter unit (1) being configured to receive a short pulp dose of at least one Weighing unit (2) of short paste fed, containing it and then unloading it into a bag that is being formed by welding units (3, 60), said sealing unit (1) comprising a base plane (18) that can be fixed to said frame (25) of the packaging machine (100) and provided with a central hole (19) superimposed and aligned vertically with the bag being formed and a diaphragm (7) with movable sheets included in a plane above and parallel to the base plane (18), characterized in that said sheets comprise a first, a second and a third sheet (4a, 4b, 4c) that are arranged radially and pivot respectively on a first, a second and a third pin (5a , 5b, 5c) fixed pe Rpendicularly and reciprocally equidistant on said base plane (18) at the vertices of a triangle and moved by moving means (10) to simultaneously rotate the sheets (4a, 4b, 4c) between a closed position of the diaphragm (7), in the that the sheets (4a, 4b, 4c) are next to each other and the short pulp dose is retained by the shutter unit (1), and an aperture position of the diaphragm (7), in which the sheets (4a, 4b, 4c) are separated from each other creating a substantially circular opening (22) aligned vertically with said central hole (19) of the base plane (18), to allow the short paste dose to discharge into the bag In training.

Description

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

DESCRIPTION

Sealing unit for a vertical flow packaging machine for short pasta

The present invention relates to a sealing unit for a vertical flow packaging machine for short pasta.

Vertical flow pasta packaging machines are known, in which the pasta is introduced into a bag that is being formed. The bag consists of a film of flexible plastic material, whose edges are progressively folded, arranged side by side and subsequently welded together by means of a longitudinal welding unit to form a tubular package. The operation of closing said package is completed with a transverse welding unit that performs the transverse welding of the tubular package before and after the operation of introducing the paste into the bag being formed. In this way, a sequence of bags filled with a previously calculated amount of pulp is obtained.

To define the quantity of pasta, said packaging machines are provided with a weighing unit adapted to measure the weight of the pasta and configured so that, when the chosen weight is reached, the desired quantity of pasta is discharged through a hopper, which puts the weighing unit in communication with a training tube on which the film is wound during the bag forming stage.

The packaging machine has a sealing unit interposed vertically between the weighing unit and the longitudinal and transverse welding unit to temporarily contain the previously weighed paste before unloading it into the forming tube below.

"Scissor-type" type shutters are known, comprising two sheets configured to contain a short paste dose of the weighing unit when the sheets are arranged side by side (closed shutter) and to discharge it into the forming tube when the leaves are reciprocally separated (shutter open).

However, "scissor" shutter units have the disadvantage of determining an extension of the flow of pulp that falls into the bag that is being formed, so that the upper level of the pulp inside the bag will never be uniform but which will show a given central prominence.

In addition to influencing the conformity of the bag, the lack of uniformity of the upper level of paste causes problems related to the upper transverse welding of the bag itself, because the paste residues can interpose between the lateral edges of the tubular package that will be welded between yes. As a consequence, there is no guarantee of an optimal closure of the bag and, therefore, of the preservation of product quality.

In addition, the extension of the paste flow that falls into the bag causes a considerable delay in the packaging process.

EP 2 484 595 A1 discloses a sealing unit for a vertical flow machine for food products, comprising a diaphragm with movable blades that alternately close to create a support for the dose of product from a weighing unit and they open to let the dose of food product fall into a bag through a central hole in the diaphragm.

In view of the prior art mentioned above, the objective of the present invention is to provide a sealing unit that allows to improve the performance of the short pasta packaging machine in terms of packaging quality and processing speed.

According to the invention, such an objective is achieved by means of a sealing unit as defined in claim 1.

The features of the present invention will become apparent from the following detailed description of a preferred embodiment thereof, shown by way of example in the accompanying drawings, in which:

Figure 1 shows a perspective view of a sealing unit according to the present invention in the closed position;

Figure 2 shows a front view of a packaging machine comprising the sealing unit of Figure 1;

Figure 3 shows on an enlarged scale the area of the packaging machine in which the sealing unit of Figure 1 is arranged;

Figure 4 shows a perspective view of the sealing unit fixed to the frame of the packaging machine;

Figure 5 shows a top plan view of the sealing unit in the closed position with the cover parts removed;

Figure 6 shows a sectional view of the aforementioned shutter unit taken along

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

from line VI-VI of Figure 5;

Figure 7 shows a sectional view of the sealing unit taken along the line VII-VII of Figure 6;

Figure 8 shows a perspective view of the shutter unit in the open position; Figure 9 shows a top plan view of the shutter unit in the open position; Figure 10 shows a sectional view of the sealing unit taken along the line X-X of Figure 9;

Figure 11 shows a sectional view of the sealing unit taken along the line XI-XI of Figure 10;

Figure 12 shows a sectional view of the leaf activating device of the sealing unit according to the present invention, taken along line XII-XII of Figure 5;

Figure 13 shows a sectional view of the same activation device taken along line XIII-XIII of Figure 9.

A sealing unit 1 for a vertical flow packaging machine for short pasta according to the present invention is shown as a whole.

A packaging machine that includes a sealing unit 1, shown and indicated in conjunction with reference number 100 in Figure 2, comprises a feeding unit 39 by means of which the paste is fed a weighing unit 2, which It weighs a dose of short paste and then introduces it into a package that is being formed consisting of a film of plastic material, whose side edges are gradually folded, arranged side by side and then welded together by a unit of longitudinal welding 60 to form a tubular package.

The operation of closing said package is completed by a transverse welding unit 3 that performs reciprocal transverse welding of the tubular package before and after the operation of introducing the paste dose into the bag being formed. In this way, a sequence of bags filled with the respective pasta doses is formed.

The shutter unit 1 is configured to receive a dose of short pulp from a weighing unit 2 for short pulp fed by the feeding unit 39, contain it and then discharge it into a forming tube 20, on which a film of plastic material 92 by means of appropriate shaped guides, the plastic material film is intended to form the tubular package 93 from which the bag receiving the paste originates from the welding units 60 and 3, as shown in Figure 3

As shown in Figure 3, the shutter unit 1 is vertically interposed between the weighing unit 2 and the welding units 3, 60. In particular, the shutter unit 1 is arranged under a hopper 23, which allows the heavy paste of the weighing unit 2 is discharged, and of the forming tube 20, which is adapted to form the tubular package 92 while carrying the paste inside the bag being formed (Figure 3)

The hopper 23 (Figures 3 and 4) is removably fixed by means of screw means 38 to the sealing unit 1 and consists of a flat base 35 from which a tube 36 with a truncated cone-shaped end centrally starts. In particular, the flat base 35 is inserted between appropriate lateral guides 40 in the sealing unit 1 and then fixed by means of said screw means 38. According to the shape of the paste, the hopper 23 can be removed and replaced with a different type of hopper that will be fixed to the shutter unit 1.

The sealing unit 1 has a base plane 18 supported by a frame 24 that can be fixed to the frame 25 of the packaging machine 100 (Figure 4), so that the sealing unit 1 is positioned vertically between the weighing unit 2 and the welding units 3, 60. In particular, the frame 24 comprises a U-shaped portion 26 supported by a pair of arms 27 which are provided with fixing means for the frame 25. The sealing unit 1 is fixed to the U-shaped portion 26 by means of a pair of folded sheets 94 connected between the U-shaped portion 26 and the sealing unit 1.

All the operations of the weighing unit 2, the sealing unit 1 and the longitudinal and transverse welding units 60, 3 of the packaging machine 100 are managed by a control unit (not shown in the figures) configured to coordinate the respective operational stages with each other.

As shown in Figures 1, 4 and 5, the sealing unit 1 comprises a diaphragm 7 formed by at least one first, a second and a third sheet 4a, 4b, 4c, which are appropriately shaped and arranged radially. The blades 4a, 4b, 4c are pivoted in a first, a second and a third pin 5a, 5b, 5c, respectively, fixed in a base plane 18 and reciprocally equidistant (at angles of approximately 120 °) along a circumference C. The base plane 18 is further provided with at least one concentric central hole 19 (Figure 9) of smaller diameter than said circumference C. Said central hole 19 includes a cylinder or coaxial cone 9, adapted to engage the forming tube 20 for take the paste to the respective bag that is being formed in the welding units 3, 60.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

The blades 4a, 4b, 4c are activated by means of movement 10 configured to rotate the blades 4a, 4b, 4c simultaneously between a closed position of the diaphragm 7, in which the blades 4a, 4b, 4c are mutually arranged side by side. of another (figures 1, 4 and 5), and an opening position of the diaphragm 7, in which the sheets 4a, 4b, 4c are separated from each other, thus creating an opening that coincides with the central hole 19 (figures 8 , 9, 10). )

During operation, the shutter unit 1 contains the heavy dose of paste in the closed position of the diaphragm 7; differently, in the opening position of the diaphragm 7, said dose is released by means of the cone 9 and the forming tube 20 in the bag being formed.

For example, the sheets 4a, 4b, 4c can be substantially petal-shaped or in all cases have any suitable shape to make the diaphragm 7; in addition, a larger number of sheets can be used.

The sheets 4a, 4b, 4c are all included in a plane that is parallel to the base plane 18 and are arranged at a given height from the latter. A second plane 21 is arranged parallel to the support plane 18 and at a lower height than the plane of the sheets 4a, 4b, 4c (Figures 1, 8, 9, 13). The second plane 21 rubs the sheets 4a, 4b, 4c so that the dust or the residues of the paste cannot be deposited between the second plane 21 and the sheets 4a, 4b, 4c thus obstructing their movement. Finally, the second plane 21 comprises an additional central hole 22 that overlaps the central hole 19 of the base plane 18 and has the same dimensions.

The mobile means 10 are activated by a device 96 comprising a brushless motor 11 driven by the control unit of the packaging machine 100. The brushless motor 11 (figures 12, 13) activates a crank 6 connected to a rod of connection 12, in turn articulated by means of a metal pin 34 to a T-handle 13 (figures 1, 5, 7-9, 11-13), which is integral with the first blade 4a and is pivoted in said first pin 5th. The T-handle 13 is then connected by means of a first and a second coupling bar 14 to the respective cranks 15 pivoted in said second and third pins 5b, 5c and integral with said second and third blades 4b, 4c of the diaphragm 7 ( Figures 5, 7, 10, 12).

In particular, the first blade 4a is fixed to the T-handle 13 by means of screws 28 that pass through a cylindrical spacer element 29 interposed between the T-handle and the blade 4a; similarly, the second and third blades 4a, 4b, 4c are fixed to the respective cranks 15 by means of screws 28 that pass through a similar cylindrical spacer element 29 interposed between each crank 15 and the blade 4b, 4c ( figures 5, 7, 9, 11).

The first and second coupling bar 14 have a first end articulated with the respective crank 15 by means of an additional pin 16 which passes through an additional cylindrical separator element interposed between each coupling bar 14 and the crank 15; a second end of the first and second coupling bar 14 is instead fixed to said T-handle 13 by means of threaded pins 17 inserted in the grooves 97 and locked therein by means of nuts 98.

The brushless motor 11 is mounted on a support structure 30 fixed on said base plane 18 of the sealing unit 1. The support structure 30 has an upper wall 31 supported by a pair of legs 42 fixed to the base plane 18 and a height greater than the plane of the sheets 4a, 4b, 4c. A housing is obtained to fix said brushless motor 11 on the upper shaft 31 so that said connecting rod 12 can be freely moved below said upper wall 31.

Furthermore, said upper wall 31 comprises a guide groove 32 in which a zero sensor 33 is housed in a translatable manner (Figure 1), connected to the control unit of the packaging machine 100 and configured to detect the moment in which the diaphragm 7 is the open position (or in the closed position) to determine a complete operating cycle of diaphragm 7 and coordinate the shutter unit 1 with the weighing unit 2 and with the welding units 3, 60.

In particular, the zero sensor 33 is an inductive sensor configured to detect the passage of the connecting pin 34 between the T-handle 13 and the connecting rod 12 moved by the crank 6 and rotated by the brushless motor 11 (Figures 14, fifteen). By detecting the metal pin 34, the control unit can identify whether the diaphragm 7 is in the open position (or in the closed position), to recognize the initial or final stage of a complete operating cycle of the diaphragm 7.

The zero sensor 33 is adjusted when moved along the guide groove 32, which allows the operator to select the most appropriate reference time; preferably, there is a first, a second and a third adjustment position to detect the closed position, the opening position, and also the intermediate opening position of the diaphragm 7, respectively (Figure 1).

In a packaging cycle of the vertical flow packaging machine 100 for short pulp, the longitudinal welding unit 60 begins to form a bag from the plastic material film, the side edges of which are gradually folded, arranged side by side. of the other and then weld each other by means of a

5

10

fifteen

twenty

25

Longitudinal welding unit to form a tubular package. The lower closure of said package is achieved by the transverse welding unit 3 that welds the two edges transversely, thus forming what will become the base of the bag.

At the same time, the weighing unit 2 first measures the weight of the fed pulp and subsequently discharges the desired amount of pulp through the hopper 23 into the sealing unit 1.

Once the heavy paste dose has been received, the shutter unit 1 contains the dose until welding of the base of the bag is completed and drops the paste dose through the formation and discharge tube 20 into the own bag In particular, the sheets 4a, 4b, 4c of the diaphragm 7 are moved by means of movement 10 and rotate simultaneously from the closed position (figures 1, 5) to the open position (figures 9, 10) of the diaphragm 7. More particularly, the brushless motor 11 moves the crank 6 which, in turn, by means of the connecting rod 12, causes a rotation of the T-handle 13, and therefore of the first blade 4a of the diaphragm 7, around the first pin 5a. The rotation of the T-handle 13 cooperating with the coupling bars 14 simultaneously also rotates the respective pivoted cranks 15 on said second and third pins 5b, 5c and therefore the second and third blades 4b, 4c of the diaphragm 7 (Figure 10 ).

In this way, the opening 19 is created which causes the paste to fall through the forming and discharge tube 20 into the bag being formed. The shutter unit 1 then goes to the closed position of the diaphragm 7, waiting to receive a new dose of paste to be discharged into the next bag.

By virtue of the sealing unit 1 with diaphragm 7, the upper level of the paste inserted in the bag will be uniform because there will be no unwanted tail of the paste flow that falls from the sealing unit, resulting in an optimum compliance of The bag itself. In addition, the risk of pulp residues present between the edges of the package is considerably reduced, so that the upper transverse weld of the bag can guarantee an optimal closure of the bag and, therefore, the preservation of product quality.

Claims (7)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 1. Sealing unit (1) that can be fixed to a frame (25) of a vertical flow packaging machine (100) for short pulp, said shutter unit (1) being configured to receive a short pulp dose of at less a unit of weighing (2) of short paste fed, containing it and then unloading it into a bag that is being formed by welding units (3, 60), said sealing unit (1) comprising a base plane (18) that it can be fixed to said frame (25) of the packaging machine (100) and provided with a central hole (19) superimposed and aligned vertically with the bag being formed and a diaphragm (7) with moving sheets included in a plane by above and parallel to the base plane (18), characterized in that said sheets comprise a first, a second and a third sheet (4a, 4b, 4c) that are arranged radially and pivot respectively on a first, a second and a third pin (5a, 5b, 5c) fixed perpendicularly and reciprocally equidistant on said base plane (18) at the vertices of a triangle and moved by moving means (10) to simultaneously rotate the sheets (4a, 4b, 4c) between a closed position of the diaphragm (7), in the that the sheets (4a, 4b, 4c) are next to each other and the short pulp dose is retained by the shutter unit (1), and an aperture position of the diaphragm (7), in which the sheets (4a, 4b, 4c) are separated from each other creating a substantially circular opening (22) aligned vertically with said central hole (19) of the base plane (18), to allow the short paste dose to discharge into the bag In training. 2. Sealing unit (1) according to claim 1, characterized in that it comprises a second plan (21), arranged in parallel with respect to said base plane (18) at a lower height with respect to the plane of the sheets ( 4a, 4b, 4c), said second plane (21) being touching the sheets (4a, 4b, 4c) and further comprising a central hole (22) superimposed on said central hole (19) of the base plane (18) and of dimensions same with respect to this. 3. Sealing unit (1) according to claim 1, characterized in that said movement means (10) comprise a brushless motor (11) driven by a control unit of the packaging machine (100) and provided with a crank (6) connected to a connecting rod (12), in turn articulated by a metal pin (34) to a T-handle (13) that forms an integral part with the first blade (4a), said handle being pivoted in T (13) in said first pin (5a) and connected through a first and a second coupling bars (14) to the respective cranks (15) pivoted in said second and third pivots (5b, 5c) and also forming an integral part with said second and third sheets (4b, 4c) of the diaphragm (7). 4. Seal unit (1) according to claim 3, characterized in that said brushless motor (11) is mounted on a support structure (30) fixed to the top of said base plane (18) of the unit of sealing (1), said support structure (30) comprising an upper wall (31) on which the brushless motor (11) is fixed so that said connecting rod (12) is free to move under said wall superior (31). 5. Seal unit (1) according to claim 4, characterized in that it comprises a zero sensor (33) housed in a guide groove (32) of said upper wall (31) and connected to the control unit of the packaging machine (100), said zero sensor (33) being configured to detect the passage of the pin (34) to determine a complete operating cycle of the diaphragm (7) and to coordinate the sealing unit (1) with the unit heavy (2) and with welding units (3, 60). 6. Seal unit (1) according to any one of the preceding claims, characterized in that it is supported by a frame (24) that can be fixed to the frame (25) of the packaging machine (100) so that the unit of Sealing (1) is placed vertically between the weighing unit (2) of short fed paste and the welding unit (3), said frame (24) comprising a U-shaped portion (26) which is supported by a pair of arms (27) provided with fixing means to the frame (25). 7. A vertical flow packaging machine (100) for short pulp, characterized in that it comprises a sealing unit (1) according to claims 1-6.