Incision unit to manufacture a single-dose break-open package

Abstract

A unit for the incision of a strip made of a plastic material to cut two distinct incisions into two opposite surfaces of the strip; the incision unit has: a conveying device, which feeds the strip along a conveying direction; two support plates, which are arranged on opposite sides of the strip, so that each support plate faces a corresponding surface of the strip; and at least two incision devices, each of which cuts an incision into a corresponding surface of the strip and has a cutting element, which is supported by a support plate, and a contrast element, which is supported by the other support plate.

1 . A unit for the incision of a strip made of a plastic material to cut two distinct incisions into two opposite surfaces of the strip in a packaging machine to manufacture a sealed single-dose break-open package; the incision unit comprises:
 a conveying device, which feeds the strip along a conveying direction;   two support plates, which are arranged on opposite sides of the strip, so that each support plate faces a corresponding surface of the strip; and   at least two incision devices, each of which cuts an incision into a corresponding surface of the strip and comprises a cutting element, which is supported by a support plate, and a contrast element, which is supported by the other support plate;   wherein the two support plates are mobile so as to translate together along a translation direction, which is orthogonal to the conveying direction;   wherein the two incision devices are arranged one next to the other and are aligned along the translation direction; and   wherein a first actuating device is provided, which cyclically moves the two support plates forward and backward along the translation direction between a first position, in which a first incision device is operated so as to cut a first incision, and a second position, in which a second incision device is operated so as to cut a second incision, which is opposite to the first incision.   
     
     
         2 . An incision unit according to  claim 1 , wherein each support plate supports the cutting element of an incision device and the contrast element of the other incision device. 
     
     
         3 . An incision unit according to  claim 1 , wherein each cutting element comprises a blade. 
     
     
         4 . An incision unit according to  claim 3 , wherein each blade is V-shaped and each contrast element is flat. 
     
     
         5 . An incision unit according to  claim 1 , wherein each incision device comprises an adjusting organ, which is coupled to the cutting element or to the contrast element and adjusts the distance between the cutting element or the contrast element and the strip. 
     
     
         6 . An incision unit according to  claim 5 , wherein the adjusting organs are all arranged on a same support plate. 
     
     
         7 . An incision unit according to  claim 1 , wherein at least one support plate is mobile so as to cyclically move forward and backward, due to a second actuating device, towards the other support late and along an incision direction, which is perpendicular to the strip and perpendicular to both the conveying direction and the translation direction. 
     
     
         8 . An incision unit according to  claim 1 , wherein the conveying device comprises at least one feeding dandy roller, which is arranged upstream of the support plates and is mobile so as to allow the strip to temporarily stop between the two support plates. 
     
     
         9 . A packaging machine to manufacture a sealed single-dose break-open package;
 the package consists of a first sheet made of a semirigid plastic material, which is arranged on top of and sealed to a second sheet made of a flexible plastic material, so as to define a sealed pocket containing a dose of a product, and has a pair of incisions to guide a controlled breaking of the first sheet;   the packaging machine comprises:   a first unwinding device to feed a first strip made of a semirigid plastic material;   a second unwinding device to feed a second strip made of a flexible plastic material;   an incision unit to cut two incisions into the first strip made of a semirigid plastic material;   a forming station, which is arranged downstream of the incision unit so as to arrange the first strip made of a semirigid plastic material on top of the second strip made of a flexible plastic material;   a first longitudinal sealing device to longitudinally and laterally seal the two strips to one another, so as to define at least one tube;   a dosing unit, which is arranged in the forming station so as to feed a dose of a product into the tube between the first strip made of a semirigid plastic material and the second strip made of a flexible plastic material;   a second transverse sealing device, which is arranged downstream of the dosing device so as to transversely seal the two strips to one another in order to define, along the tube, a series of pockets, each containing a dose of product; and   a cutting device, which is arranged downstream of the forming station so as to transversely cut the tube in order to separate, in sequence, the sealed single-dose packages ( 1 );   wherein the incision unit is manufactured according to  claim 1 .   
     
     
         10 . A method for the incision of a strip made of a plastic material to cut two distinct incisions into two opposite surfaces of the strip in a packaging machine to manufacture a sealed single-dose break-open package; the incision method comprises the steps of:
 conveying the strip along a conveying direction and between two support plates, so that each support plate faces a corresponding surface of the strip;   cutting the strip by means of at least two incision devices, each cutting an incision into a corresponding surface of the strip;   translating the two support plates together along a translation direction, which is orthogonal to the conveying direction; and   cyclically moving the two support plates forward and backward along the translation direction between a first position, in which a first incision device is operated so as to cut a first incision, and a second position, in which a second incision device is operated so as to cut a second incision, which is opposite to the first incision.   
     
     
         11 . A method for the incision of a strip made of a semirigid material according to  claim 10 , wherein the two incision devices are arranged one next to the other and are aligned along the translation direction. 
     
     
         12 . A method for the incision of a strip made of a semirigid material according to  claim 10 , wherein the strip made of a semirigid material is temporarily stopped during the strip incision step. 
     
     
         13 . A dosing unit of a packaging machine for sealed single-dose packages; the dosing unit comprises:
 a tank holding a fluid product;   at least one feeding duct, which originates from the tank and ends with a delivery mouth; and   a pump, which is peristaltic pump and is arranged along the feeding duct so as to feed the fluid product from the tank to the delivery mouth;   wherein the tank is pressurized at a pressure that is higher than the atmospheric pressure.   
     
     
         14 . A dosing unit according to  claim 13 , wherein the tank has at least one nozzle, which is arranged in an upper portion of the tank and is suited to blow a jet of compressed air into the tank. 
     
     
         15 . A dosing unit according to  claim 13 , wherein the peristaltic pump has an impeller, which supports at least four thrust elements. 
     
     
         16 . A dosing unit according to  claim 13 , wherein the peristaltic pump has an impeller, which supports at least eight thrust elements. 
     
     
         17 . A dosing unit according to  claim 13  and comprising a shut-off valve, which is arranged along the feeding duct upstream of the pump. 
     
     
         18 . A dosing unit according  claim 13 , wherein the fluid product is a sanitizer gel. 
     
     
         19 . A unit to print a deformable plastic material strip of a packaging machine for sealed single-dose packages; the printing unit comprises:
 a conveying device, which feeds the strip along a conveying direction;   a printing device, which is arranged in a fixed position along the conveying device and faces a first surface of the strip so as to print a pattern on the strip; and   a contrast plate, which is independent and separate from the conveying device, is arranged in a fixed position along the conveying device, and is parallel to and faces the printing device so that the strip is arranged between the contrast plate and the printing device;   wherein the printing device comprises a printing head, which in use contacts the strip with a given pressure so as to print a pattern on the strip; and   wherein the contrast plate comprises at least one nozzle, which opens up onto a second surface of the strip and is suited to release a blow of compressed air so as to create a pressurized air cushion in correspondence to the second surface of the strip that is opposite to the printing device, said air cushion constitutes a deformable contrast against which the printing head pushes the strip.   
     
     
         20 . A printing unit according to  claim 19 , wherein the contrast plate comprises a plurality of nozzles that are spaced apart from one another. 
     
     
         21 . A printing unit according to  claim 19 , wherein the printing device is a heat transfer printing device. 
     
     
         22 . A printing unit according  claim 19 , wherein the printing head is mobile along a printing direction, which is orthogonal to the conveying direction and orthogonal to the strip. 
     
     
         23 . A printing unit according to  claim 19 , wherein the compressed air is fed to the nozzle with a pressure ranging from 2 to 6 bar. 
     
     
         24 . A printing unit according to  claim 19 , wherein the compressed air is fed to the nozzle with a pressure ranging from 3 to 5 bar. 
     
     
         25 . A method to print a deformable plastic material strip of a packaging machine for sealed single-dose packages; the printing method comprises the steps of:
 conveying the strip along a conveying direction by means of a conveying device;   printing a first surface of the strip by means of a printing device, which is arranged in a fixed position along the conveying device and is coupled to a contrast plate, which is independent and separate from the conveying device, is arranged in a fixed position along the conveying device, and is parallel to and faces the printing device so that the strip is arranged between the contrast plate and the printing device; wherein the printing device comprises a printing head, which in use contacts the strip with a given pressure so as to print a pattern on the strip; and   
       releasing a blow of compressed air through a nozzle, which is obtained through the contrast plate and opens up onto a second surface of the strip so as to create a pressurized air cushion in correspondence to the second surface of the strip that is opposite to the printing device, said air cushion constitutes a deformable contrast against which the printing head pushes the strip.