US3513627A - Aseptic packaging - Google Patents

Description

May 2.6, 1970 Filed Sept. l, 1967 lllIl',Ill/l/lllllllllllllllllllll/111111111vill/1111111110 'lll/111 E. F. DoucETTE ETAL ASEPTIC PACKAGING rllll/lll/IIIIIIIIIIIllll,llI/lllll/lIl/ll/ll//Avll/1111111111 3 Sheets-Sheet 1 May 26, 1970 E. F.nou`cE'r1-E ETAI- 3,513,627

ASEPTIC PACKAGING 3 Sheets-Sheet 2 Filed Sept. 1. 1967 FIG. 2

May 26, 1970 E. F. noucET'rE ETAI- 3,513,627

AsEPTrc PACKAGING Filed Sept. 1. 196'? Y 3 Sheets-Sheet 3 United States Patent O U.S. Cl. 53--180 10 Claims ABSTRACT OF THE DISCLOSURE In a form-fill-seal package machine, a web of packaging material being fed to the mandrel of the machine is sterilized as it travels to the mandrel and maintained sterile until it is formed into tubing around the mandrel and until formation of lilled sealed packages from the tubing by being passed through a sterilizing chamber, wherein the web is sterilized by treatment with a sterilizing medium the chamber being supplied with a sterile gas under suiiicient pressure to prevent room air, which may be unsterile, from entering the chamber. The mandrel is enclosed by a shroud, and the space in the shroud around the mandrel is supplied with sterile gas from the chamber so as to maintain a sterile environment for the forming of the tubing, and the lling and sealing.

BACKGROUND OF THE INVENTION The invention pertains t aseptic packaging of various products via the form-till-seal packaging technique. Among the problems encountered in aseptic packaging by this technique are the sterilization of the product, and the sterilization of the packaging material used to form the packages and the forming, illing and sealing of the packages in a sterile environment. This invention is concerned with the latter problem, particularly with reference to production of aseptic packages by means of a form-fill-seal packaging machine of the type such as shown in U.S. Pat. No. 3,221,469, issued Dec. 7, 1965, entitled Method and Apparatus for Forming Tetrahedron Shaped Packages.

SUMMARY OF THE INVENTION Among the several objects of this invention may be noted the provision in a form-ll-seal machine, such as that shown in the above-noted U.S. patent, having a mandrel around which a web of packaging material is formed into tubing and having means foi forming a longitudinal seam for the tubing, feeding the tubing downward off the lower end of the mandrel and forming transverse seals across the tubing below the lower end of the mandrel to form packages, with means for lling the packages, of means for eilectively sterilizing the packaging material as it is fed toward the mandrel and maintaining it sterile until it reaches the mand-rel, and the further provision of means for establishing a sterile environment for the packaging material along the mandrel to insure that it remains sterile until the sealing of the packages has been completed. The sterilizing means comprises a chamber having an opening for entry of the web of packaging material from a roll of the material and an opening for exit of the web from the chamber to the mandrel, and means for maintaining a sterile atmosphere in the chamber while exposing the web in the chamber to a sterilizing medium, entry of outside atmosphere through said openings into the chamber being prevented thereby to prevent contamination of the chamber. To establish a sterile environment for the web material along the mandrel, a shroud is provided enclosing the mandrel, and a sterile atmosphere is maintained around the mandrel in the shroud by the same means as maintains the sterile atmosphere in the chamber. Other objects 3,513,627 Patented May 26, 1970 ICC and features will be in part apparent and in part pointed out hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation, partly broken away and in section, illustrating a machine of the type shown in U.S. Pat. No. 3,221,469 having auxiliary aseptic packaging equipment of this invention;

FIG. 2 is a partial front elevation of FIG. 1;

FIG. 3 is a horizontal section on line 3 3 of FIG. 2; and

FIG. 4 is a View similar to FIG. 1 illustrating a modification.

`Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, there is indicated at A in FIG. 1 a form-ll-seal packaging machine which, as illustrated, is of the type shown in the above-noted U.S. Pat. No. 3,221,469. In this machine, a web W of exible packaging material, lwhich is heat-scalable on one face as indicated at S, is drawn from a web roll R and formed into tubing T around a vertical hollow mandrel 1, with its heat-scalable side S on the inside, and with its side margins brought together in inside-ace-to-inside-face relation and projecting outward. The exible packaging material may comprise, for example, laminated layers of paper and metal foil with a coating of thermoplastic material, such as polyethylene, at S.

The tubing T is intermittently fed downward ol the lower end of the mandrel in package length increments by grasping the outwardly projecting side margins and pulling downward. The grasp on the side margins is taken by a pair of vertically positioned heat-sealing ba-rs indicated at 3, which apply heat as well as pressure to the side margins as the tubing is fed downward to cause the side margins to become heat-sealed together thereby to form a longitudinal seam L for the tubing. Bars 3 are adapted to move laterally inward and outward as well as vertically upward and downward. They are brought together to clamp the side margins, then move downward, then open, and return upward to clamp the side margins and initiate downward feed of the tubing through another package length increment. As they move upward, the tubing dwells for an interval until they reach the top of their stroke and clamp the side margins.

During each dwell interval between successive downstrokes of the tubing, a transverse package-end-forming seal is made across the tubing Ibelow the lower end of the mandrel. Successive end seals may be in vertical planes at right angles to one another so that the packages are of tetrahedron shape. The end seals are made by sealing heads indicated at 5 operating in a horizontal plane below the lower end of the mandrel.

The machine comprises a supporting structure 7 including a table 9 (corresponding to table 13 of U.S. Pat. 3,221,469) having an opening for downward passage of the tubing off the lower end of he mandrel, and which carries the end sealing heads 5 (which correspond to heads 5A, 5B, 5C and 5D shown in said patent). Above the table is a superstructure including a housing 15 for various parts of the machine. Extending rearward from this housing is a bracket 17 for holding the roll R. In front of this housing is a vertical post 19 (corresponding to post 4.3 of said patent) on which is vertically slidable a carriage 21 (corresponding to carriage 45 of said patent) which carries the longitudinal seam sealing bars 3. The mandrel 1 is mounted as indicated at 23 toward its upper end, and extends down from its mounting in front of the post. The

3 length of the mandrel is such that its lower end is somewhat above the table 9.

In accordance with this invention, a sterilizing chamber C for the web W is mounted on top of housing 15. This chamber C is of rectangular box form, having a bottom 25, top 27, front and rear walls 29 and 31, and side walls 33, one of which side walls is shown broken away so that parts in the chamber may be seen. One of the side walls is provided with a door 35 for access to the chamber. The chamber C projects forward from housing over the mandrel, and, as shown, also projects rearward from the housing 15.

Adjacent the upper end of the rear wall 31 of the chamber C is an opening 37 for entry of the web W passing from the roll R. The web, unwinding from the roll, is trained around a guide 39, a tension roller 41 and a guide 4.3, thence passes through a photocell unit 45 mounted on the outside of wall 31 (this photocell unit being provided for web registration purposes and being unessential so far as the present invention is concerned), and thence around a guide roller 47 mounted on wall 31 adjacent its upper end, and through opening 37 into the chamber.

Mounted on the inside of Wall 31 adjacent its upper end is a receptacle 49 holding a sponge 51 which is soaked with a germicidal liquid, such as hypochlorite solutions for example. A guide roller 53 extends horizontally between the side walls 33 of the chamber forward of the sponge receptacle. The web entering chamber C after traveling over roller 47 passes horizontally over sponge 51 and thence to roller 53, its plastic-coated face S wiping over the top of the sponge so that it is wetted by the germicidal liquid. The front wall S5 of the receptacle 49 has a slot 57 for passage of the web.

From the roller, the web travels downward at an angle and passes between upper and lower rollers 59 and 61 disposed in a bath 63 of a germicidal liquid in a receptacle 65 mounted on the bottom of the chamber C. From the rollers 59 and 61, the web travels upward at an angle to a roller 67 extending horizontally between the side walls 33 adjacent the top of the chamber C, thence downward at an angle and passes between upper and lower rollers 69 and 71 disposed in a second bath 73 of germicidal liquid in a receptacle 75 mounted on the bottom of chamber C. From the rollers 69 and 71, the web travels upward at an angle to a series of guide rollers 77, 79 and 81, and then vertically downward from the last of these rollers through an exit opening 83 in the bottom of the chamber C tothe mandrel 1.

The germicide-wetted face of the reach of the web S passing from roller 53 to rollers 59 and 61 is exposed to germicidal ultraviolet rays from one or more ultraviolet lamps 85 suitably mounted in chamber C arranged at an angle corresponding to the angle of this reach of the web. The germicide-wetted face S of the reaches of the web passing from rollers 59 and 61 t0 roller 67 and from the latter to rollers 69 and 71 is exposed to germicidal ultraviolet rays from ultraviolet lamps 87 extending transversely of the chamber C adjacent its bottom. Heater plates 89 (e.g., electrical resistance heater plates) are provided for heating the reach of the web from the second germicidal bath 73 to the roller 77 for rapid drying of the web. A final exposure to germicidal ultraviolet rays may be given the reach of web extending down from roller 81 to exit opening 83 by one or more ultraviolet lamps 91.

The chamber C is maintained lled with sterile air under pressure slightly in excess of ambient air pressure (room air pressure) via a sterile air inlet 93 at the top of the chamber. This sterile air may lbe supplied via a blower 95 delivering air from the room through a heater 97 in which the air is heated to a temperature of 800 F., for example, suflicient for sterilization, thence through a cooler 99 in which it is cooled generally to room ternperature, and thence through a millipore filter 101 to the inlet 93.

A shroud 103 (see FIGS. 1-3) extends down from the forward portion of chamber C to the table 9 in front of the mandrel, enclosing the latter. The shroud, which may be formed of a suitable transparent plastic material, i-s of channel-shape in horizontal cross section, and is mounted in position around the mandrel enclosing the mandrel from chamber C down to table 9, with the rear edges of the sides of the shroud engaging the front plates 105 and 107 (corresponding to plates 37 and 39 shown in U.S. Pat. No. 3,221,469) of the machine. With this arrangement, the space in the shroud around the mandrel is supplied with sterilized air fromcharnber C via web exit opening 83. This is under pressure somewhat higher than ambient air pressure (room air pressure); hence a sterile atmosphere is maintained around the mandrel in the shroud.

At 109 in FIG. 2 is diagrammatically indicated the filling means for filling the packages as they are formed. This may comprise a filler pump of the type shown in U.S. Pat. No. 3,221,469 for delivering measured charges of a liquid or semiliquid product via a product delivery line 111 extending through the mandrel 1. Or it may comprise suitable means for delivering measured charges of a owable solid material (e.g., powder).

Operation is as follows:

As the web W travels through the sterilizing chamber C to the mandrel 1, it is sterilized by the application thereto of germicidal liquid by sponge 51 and in the baths 63 and 73, and by exposure to ultraviolet rays from lamps 85, 87 and 91, and is dried by heat from heater plates 89. Blower is maintained in operation to deliver air through heater 97, in which the air is heated to a temperature sufiicient to sterilize it, thence through cooler 99 wherein it is cooled generally to room temperature, thence through millpore filter 101 for filtering out foreign matter, and via inlet 93 into chamber C. Thus, sterile air under pressure above room air pressure is delivered to chamber C to maintain a sterile atmosphere therein. The sterile air in chamber C being under pressure somewhat in excess of room air pressure, entry of room air into chamber C via openings 37 and 83 is prevented; thus a sterile atmosphere is maintained in chamber C to prevent contamination thereof and to insure noncontamination of the sterilized web. Sterile air from chamber C exits through opening 83 and fills the space in the shroud 103 around the mandrel to establish a sterile environment for the web material along the mandrel, where the web is formed into the tubing, and the longitudinal seam L is formed, and down to the region where the package end seals are formed, thus insuring that the web remains sterile until the sealing of the packages has been completed.

FIG. 4 illustrates a modification of the above wherein the web W travelling through the sterilizing chamber C to the mandrel 1 is sterilized by exposure to a sterilizing gas medium instead of a liquid sterilizing medium. As shown therein, the receptacle 49, baths 63 and 73, lamps 85, 87 and 89 and heater plates 91 are omitted. A sterilizing gas, such as ethylene oxide or methyl bromide, is introduced under pressure into the chamber C from a cylinder 113 containing a pressurized supply of the gas via a connection 115. In the case of use of ethylene oxide, for example, the cylinder may contain a mixture of about 10% ethylene oxide and 90% carbon dioxide. The gas is introduced into chamber at a pressure somewhat in excess of room air pressure; thus it prevents entry of room air into chamber C via openings 37 and 83 (which should be made as small as possible) and, in escaping from opening 83, fills the space in the shroud 103 to establish a sterile environment in the shroud. A vent hood 117 is provided above the machine for venting gas exiting from opening 37 and the lower end of the shroud.

From the above it will appear that as to each of the systems of FIGS. l and 4, the web is sterilized in passing through the chamber C by exposure to a sterilizing medium, with a sterile atmosphere being maintained in the chamber, entry of outside air into the chamber being prevented due to pressurization of the chamber, and that the formation of the packages occurs in a sterile environment established within shroud 103 via communication of the sterile atmosphere from the chamber through opening 83 to the space within the shroud.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In a form-ill-seal packaging machine having a mandrel around which a web of packaging material is formed into tubing and having means for forming a longitudinal seam for the tubing, feeding the tubing downward off the lower end of the mandrel, and forming transverse seals across the tubing below the lower end of the mandrel to form packages, and means for filling the packages, the provision of a sterilizing chamber having an opening for entry of the web from a roll of the packaging material and an opening for exit of the web from the chamber to the mandrel, and means for maintaining a sterile atmosphere in said chamber while exposing the web in the chamber to a sterilizing medium, said means for maintaining the sterile atmosphere in said chamber comprising means for maintaining sterile gas in said chamber at a pressure sufficient to prevent entry of outside air to said chamber through said openings, said means for maintaining sterile gas in said chamber comprising means for blowing room air into said chamber, and means for sterilizing said air.

2. In a form-ill-seal packaging machine as set forth in claim 1, means for filtering the air prior to its entry into the chamber.

3. In a form-fill-seal packaging machine as set forth in claim 1, said means for sterilizing said air comprising means for heating the air to a temperature suliicient to sterilize it, and means for cooling the heated sterile air.

4. In a form-lill-seal packaging machine as set forth in claim 1, the chamber Abeing mounted above the mandrel, and the exit opening being in the bottom of the chamber in line with the mandrel.

S. In a form-fill-seal packaging machine as set forth in claim 4, a shroud enclosing the mandrel below said chamber, the space in the shroud around the mandrel being pressurized with sterile air from the chamber via said exit opening.

6. In a form-fill-seal packaging machine as set forth in claim 1, said chamber having means therein for applying a germicidal liquid to the web, and means therein for heating the web to dry it.

7. In a form-fill-seal packaging machine as set forth in claim 1, said chamber having means therein for exposing the web to germicidal ultraviolet rays.

8. In a form-ll-seal packaging machine as set forth in claim 1, said chamber having means therein for applying a germicidal liquid to the web, means therein for heating the web to dry it, and means therein for exposing the web to germicidal ultraviolet rays.

9. In a form-fill-seal packaging machine having a mandrel around which a web of packaging material is formed into tubing and having means for forming a longitudinal seam for the tubing, feeding the tubing downward off the lower end of the mandrel, and forming transverse seals across the tubing below the lower end of the mandrel to form packages, and means for filling the packages, the provision of a sterilizing chamber above the mandrel having an opening for entry of the web from a roll of the packaging material and an opening in the bottom thereof in line with the mandrel for exit of the web from the chamber to the mandrel, a shroud around the mandrel, and means for sterilizing the web in said chamber and maintaining a sterile room-temperature atmosphere in said chamber and in the space in the shroud around the mandrel comprising means for introducing into said chamber and maintaining therein a sterilizing gas adapted to sterilize the web at room temperature with the gas at a pressure above atmospheric air pressure and at room temperature, the space in the shroud around the mandrel 4being pressurized with said gas from the mandrel via said exit opening.

10. In a form-ll-seal packaging machine as set forth in claim 9, a venting hood above the machine for venting spent gas from the machine.

References Cited UNITED STATES PATENTS 2,918,770 12/1959 Stocker 53-180 3,383,831 5/1968 Goldsmith et a1. 53-180 X THERON F. CONDON, Primary Examiner E. F. DESMOND, Assistant Examiner U.S. Cl. X.R. 21--93

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