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EP-4741294-A2 - A METHOD AND A MACHINE FOR THE PRODUCTION OF POUCHES CONTAINING A RESPECTIVE QUANTITY OF A LOOSE MATERIAL, IN PARTICULAR SNUS

EP4741294A2EP 4741294 A2EP4741294 A2EP 4741294A2EP-4741294-A2

Abstract

A machine (6) for the production of pouches (1) containing a respective quantity (2) of a loose material, in particular snus, is provided, comprising a forming station (13) configured to enclose each quantity (2) within a wrapping material band (11) comprising, in turn, a wrapping device (14) at which the wrapping material band (11) is wound to form a tubular wrap (8) having a longitudinal extension wherein a first edge of the wrapping material band (11) partially overlaps a second edge of the wrapping material band (11) defining an overlapping area; a longitudinal sealing unit (15) configured to longitudinally seal the tubular wrap (8) at the overlapping area; and a transverse sealing unit (16) configured to make transverse seals (5) of the tubular wrap (8) so as to form a continuous succession of pouches (1) connected to each other at said transverse seals (5). The transverse sealing unit (16) is configured to perform impulse sealing of the wrap (8).

Inventors

  • GHIOTTI, ROBERTO

Assignees

  • Sasib S.p.A.

Dates

Publication Date
20260513
Application Date
20251027

Claims (14)

  1. A machine (6) for the production of pouches (1) containing a respective quantity (2) of a loose material, in particular snus, fed along a packaging path (Q); the machine (6) comprises a forming station (13) configured to enclose each quantity (2) within a wrapping material band (11) with: - a wrapping device (14), in the area of which the wrapping material band (11) is rolled up so as to form a tubular wrap (8) having a longitudinal extension, wherein a first edge of the wrapping material band (11) partially overlaps a second edge of the wrapping material band (11), thus defining an overlapping area; - a longitudinal sealing unit (15) configured to longitudinally seal the tubular wrap (8) in the overlapping area; and - a transverse sealing unit (16) arranged downstream of the longitudinal sealing unit (15) along the packaging path (Q) and configured to make the transverse seals (5) of the tubular wrap (8) so as to form a continuous succession of pouches (1) connected to each other at said transverse seals (5); the machine is characterised in that the transverse sealing unit (16) is configured to perform impulse sealing of the tubular wrap (8).
  2. The machine (6) according to claim 1, wherein the transverse sealing unit (16) comprises a first device (25), which comprises a first sealing bar (29*) having a respective first heating element (31*) intended for heating the tubular wrap (8) and preferably obtained by means of an electrical resistance with a reduced thickness connected to a control unit, by which it is controlled by means of current impulses.
  3. The machine (6) according to claim 2, wherein the transverse sealing unit (16) comprises a second device (26), which comprises a second sealing bar (29**) having a respective second heating element (31*) intended for heating the tubular wrap (8) and preferably obtained by means of an electrical resistance with a reduced thickness connected to a control unit, by which it is controlled by means of current impulses.
  4. The machine (6) according to claim 2, wherein the transverse sealing unit (16) comprises a second device (26) comprising a countering element, which cooperates with the first device (25) to make the transverse seals (5) of the tubular wrap (8).
  5. The machine (6) according to claim 2 and/or 3, wherein the first and/or the second sealing bar (29) comprise a support body (30) for the respective heating element (31).
  6. The machine (6) according to claim 5, wherein the first and/or the second sealing bar (29) comprise a number of intermediate layers (32) interposed between the support body (30) and the heating element (31), preferably made of a plastic material.
  7. The machine (6) according to any one of the preceding claims, wherein the transverse sealing unit (16) is provided with a conditioning device.
  8. The machine (6) according to claims 5 and 7, wherein the first and/or the second sealing bar (29) comprise a duct, which is obtained within the support body (30) and inside which a conditioning fluid flows.
  9. The machine (6) according to any one of the preceding claims, wherein the transverse sealing unit (16) is configured to follow a trajectory divided into a first straight segment, wherein the transverse seals (5) are made, and a second circular arc-shaped segment.
  10. The machine (6) according to any one of the previous claims and comprising a cutting device (17) arranged downstream of the transverse sealing unit (16) along the packaging path (Q) and separated from the transverse sealing unit (16); the cutting device (17) is configured to transversely cut the continuous succession of pouches (1) connected to each other at said transverse seals (5) so as to separate the individual pouches (1).
  11. The machine (6) according to claim 10 and comprising an advancing device (18) interposed between the transverse sealing unit (16) and the cutting device (17); wherein the advancing device (18) is configured to feed the continuous succession of pouches (1) coming from the transverse sealing unit (16) towards the cutting device (17) and preferably comprises a pair of belts (19) looped around respective pulleys and overlapping one another to define a channel for the passage of the continuous succession of pouches (1).
  12. The machine (6) according to claim 10 or 11 and comprising a first optical sensor configured to detect the quality of the seals in the continuous succession of pouches (1); wherein said first optical sensor is interposed between the transverse sealing unit (16) and the advancing device (18).
  13. The machine (6) according to any one of claims 10 to 12 and comprising a second optical sensor configured to detect the cutting quality of the individual pouches (1) and/or the transverse dimension of the transverse seals (5); wherein said second optical sensor is arranged downstream of the cutting unit (17) along the packaging path (Q).
  14. A method for the production of pouches (1) containing a quantity (2) of a loose material, in particular snus, comprising in succession: - a step in which to wrap a wrapping material band (11) around a wrapping device (14) so as to form a tubular wrap (8) having a longitudinal extension, wherein a first edge of the wrapping material band (11) partially overlaps a second edge of the wrapping material band (11), thus defining an overlapping area; - a longitudinal sealing step, during which the tubular wrap (8) is longitudinally sealed in the overlapping area; and - a transverse impulse sealing step of the tubular wrap (8) so as to form a continuous succession of pouches (1) connected to one another.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This patent application claims priority from Italian patent application no. 102024000025425 filed on 12 November 2024, the entire disclosure of which is incorporated herein by reference. TECHNICAL FIELD This invention relates to a machine for the production of pouches (or sachets) containing a quantity of a loose product (that is, a non-compact product), in particular snus, and to a method for producing pouches containing a quantity of a loose product, in particular snus. This invention can be advantageously applied to the production of snus pouches (that is, permeable pouches for oral use that each contain a predetermined quantity of a loose, that is, non-compact product, that is more or less wet and, for example, nicotine-based), to which the discussion that follows will explicitly refer without any loss of generality thereby. PRIOR ART As is well known, a snus pouch is essentially rectangular in shape, is made from a wrapping sheet that is folded back on itself to form a closed shape around a quantity of powdered material, and is stabilised by means of a longitudinal seal and a pair of opposite, transverse seals. Typically, a wrapping machine for producing snus pouches comprises a conveyor device for conveying a wrapping material band along a packaging path, a wrapping station arranged along the packaging path, wherein the wrapping material band is wound to form a tubular wrap having a longitudinal extension around a wrapping duct, and a feeding device for the loose material that terminates at the inlet of the wrapping duct and is configured to successively feed the loose product quantities into the tubular wrap (around which the wrapping material is folded to form the tubular wrap) by means of compressed air. The wrapping machine also comprises a longitudinal sealing unit to longitudinally seal the tubular wrap at an overlapping area of the wrapping material band; a transverse sealing unit to transversely seal the tubular wrap so as to form an alternating succession of sealing areas and areas containing a quantity of loose product; and a cutting unit to transversely cut the tubular wrap at the transverse sealing areas so as to separate the individual snus pouches. Known transverse sealing units mostly perform heat sealing and comprise two opposing sealing rollers that cooperate together to press against each other (that is, pinch together) the tubular wrap, are rotatably mounted around two corresponding horizontal rotation axes, and are rotated by the same actuator device. In known transverse sealing units when the wrapping material band and/or powdered material come into contact with the sealing rollers at high temperatures they crystallise, leaving residues and impurities. For this reason, transverse sealing units of the ultrasonic type that do not heat the materials have been proposed. However, the ultrasonic sealer, which involves the use of a sonotrode and a striker, is a technology that is easily subject to wear and tear and requires very frequent maintenance. Therefore, there is a need for solutions that limit the heating of materials, in order to obtain high quality products from an aesthetic and organoleptic point of view, that are reliable and that reduce maintenance work on the machine. Patents US5231817, FR2819482 and US4512138 describe machines for producing pouches of a known type. DESCRIPTION OF THE INVENTION The purpose of this invention is, therefore, to provide a machine for the production of pouches containing a quantity of a loose material, in particular snus, that is free from the drawbacks of the state of the art and is also easy and inexpensive to manufacture. In accordance with this invention, a machine for the production of pouches containing a respective quantity of loose material, in particular snus, is provided, comprising a forming station configured to enclose each quantity within a wrapping material band comprising, in turn, a wrapping device at which the wrapping material band is wound to form a tubular wrap having a longitudinal extension wherein a first edge of the wrapping material band partially overlaps a second edge of the wrapping material band defining an overlapping area; a longitudinal sealing unit configured to longitudinally seal the tubular wrap at the overlapping area; and a transverse sealing unit configured to make transverse seals of the tubular wrap so as to form a continuous succession of pouches connected to each other at said transverse seals; wherein the transverse sealing unit is configured to carry out impulse sealing of the tubular wrap and comprises a first sealing device and a second sealing device that cooperate to make the transverse seals. According to a preferred embodiment, the first sealing device is defined by a first sealing bar having a respective first heating element intended for heating the tubular wrap and preferably obtained by means of an electrical resistance with reduced thickness connecte