US3820300A - Method of and machine for producing sterile packages - Google Patents

Abstract

A machine or apparatus and method for producing a plurality of sterile liquid or semi-liquid filled packages from a supply of synthetic plastic film web. The apparatus includes a supporting roll for a supply of web, a sterilization bath for sterilizing the web, and successively arranged heating, forming, filling, closing and cutting stations for carrying out the respective operations of heating the web, forming containers in the web, filling the containers, closing the containers, and cutting the containers from the web. A sterile tunnel encloses that portion of the machine between the forming and closing stations. Spray nozzles are arranged throughout the inside of said tunnel for spraying an excess pressure of sterile air during operation of the machine. A liquid disinfectant supply is arranged in communication with a feed pipe for the sterile air such that the disinfectant is sucked by ventura effect into the feed pipe and intermixed with the sterile air prior to being atomized and sprayed by the nozzles. Prior to starting of the package forming operations, the liquid disinfectant supply is used for disinfecting the inside of the tunnel. Once the disinfectant is used up, the sterile air supply continues to supply an excess pressure of pure sterile air to the tunnel during normal operation of the machine.

Description

Elnited States Patent [191 Reineclte et a1.

[11] 3,820,300 June 28, 1974 METHOD OF AND MACHINE FOR PRODUCING STERILE PACKAGES [75] Inventors: Giinter Reinecke, Wuppertal;

Dietrich Linke, Lintorf, both of Germany [73] Assignee: Rheinmetall GmbI-l, Dusseldorf,

Germany 22 Filed: Apr. 28, 1972 211 Appl.No.:248,730

[52] US. Cl 53/29, 53/30, 53/110, 53/167, 53/180, 21/58, 21/80 [51] Int. Cl B651) 43/00 [58] Field of Search 53/29, 30, 184, 180, 110, 53/167; 21/58, 78, 80, 122-125 Primary Examiner-Andrew R. Juhasz Attorney, Agent, or Firm-Craig & Antonelli ABSTRACT A machine or apparatus and method for producing a plurality of sterile liquid or semi-liquid filled packages from a supply of synthetic plastic film web. The apparatus includes a supporting roll for a supply of web, a sterilization bath for sterilizing the web, and successively arranged heating, forming, filling, closing and cutting stations for carrying out the respective operations of heating the web, forming containers in the web, filling the containers, closing the containers, and cutting the containers from the web. A sterile tunnel encloses that portion of the machine between the forming and closing stations. Spray nozzles are arranged throughout the inside of said tunnel for spraying an excess pressure of sterile air during operation of the machine. A liquid disinfectant supply is arranged in communication with a feed pipe for the sterile air such'that the disinfectant is sucked by ventura effect into the feed pipe and intermixed with the sterile air prior to being atomized and sprayed by the nozzles. Prior to starting of the package forming operations, the liquid disinfectant supply is used for disinfecting the inside of the tunnel. Once the disinfectant is used up, the sterile air supply continues to supply an excess pressure of pure sterile air to the tunnel during normal operation of the machine.

25 Claims, 2 Drawing Figures PATENT'EDJUH28 1914 3,820.300

Fig.2 1, 2.3 I; A

20 if, 19 19 i f J I 9 IT 19 15 DUB UUU

METHUD F AND MACH-ENE FOR PRODUCING STERILE PACKAGES BACKGROUND AND SUMMARY OF THE INVENTION The invention relates to a machine or apparatus and method for producing sterile packages, filled with liquid or semi-liquid foodstuffs and semi-luxuries. A web of synthetic film is drawn off a supply roller and guided through a sterilization bath and is then supplied in succession to heating, forming, filling, closing and cutting stations, 21 common sterile tunnel extending over several of these stations, in which tunnel an excess pressure of sterile gas is maintained during the operation of the machine.

It has been contemplated to employ machines of the aforementioned general type for producing sterile packages. Such a machine utilizes a protective tunnel which extends from the fonning to the closing station and encloses the web of film, and in which a slight excess pressure of sterilized air is maintained. A compressor furnishes a higher pressure of sterilized air in the area of the formed containers. This higher pressure is directed to causing all the bacteria to be concentrated into a comparatively small volume.

In this machine arrangement described immediately above, sterilization is confined to the packaging material, whilst the mechanical devices for conveying and handling the web of film remain untreated. However, new bacteria may be continuously brought into the sterilization tunnel by conveying chains, which pass through the sterilization and then come into contact with the outside air, whereby the packaging material in the turnnel can be infected.

Another contemplated sterilization device, which can be used in the manufacture of tubular packages, is characterized in that the flat film of synthetic material is passed through a sterilization bath before it is shaped into a tube. Since the machine for manufacturing tubular packages is located in a sterile room, disinfection of the machine parts coming into contact with the packaging material is unnecessary.

The present invention contemplates providing an improved machine for the manufacture of packages made of a synthetic film and filled with liquid or semi-liquid foodstuffs and semi-luxuries. This improved machine utilizes a sterile tunnel in such a way that both the web of film as well as the machine parts coming into contact with the filling and/or the web of film are made sterile by the simplest means and maintained sterile until the package is sealed.

According to one aspect of the present invention there is contemplated the provision of an arrangement for disinfecting and sterilizing structure enclosed by a sterile tunnel on a machine of the type which produces a plurality of sterile liquid or semi-liquid filled packages from a synthetic film web. This arrangement includes nozzle means positioned for spraying into the tunnel, sterile gas supply means for supplying sterile gas to the nozzle means such that an excess pressure of sterile gas may be maintained in the tunnel during operation of the machine, and liquid disinfectant supply means for supplying liquid disinfectant to said nozzle means for disinfecting the inside of the tunnel prior to initiation of operation of themachine.

According to a further aspect of the invention there is contemplated the provision of a machine for producing sterile liquid or semi-liquid filled packages comprising successive means for supporting a supply of plastic film web, a sterilization bath for the web heating, forming, filling, closing and cutting stations, a sterile tunnel enclosing at least some of said stations with an excess pressure of sterile gas being maintained in said tunnel during operation of the machine, and a plurality of nozzles spaced apart along said tunnel, said nozzles being connected to means for supplying a flow of said sterile gas and also to means for supplying a liquid disinfectant.

In a preferred embodiment contemplated by the present invention, sterile air is supplied under pressure from a filter through a central pipe to manifold provided with connections to the nozzles. A feed-pipe operating according to the injector principle opens into the central pipe, which feed-pipe is connected to a container containing the liquid disinfectant.

According to another aspect of the present invention, there is contemplated a method of producing sterile liquid or semi-liquid filled packages in a machine comprising the successive steps of:

Supplying an atomized disinfectant to portions of the machine by way of nozzles arranged in a sterile tunnel enclosing said portions,

forming a plurality of containers from a synthetic film web at a forming station of the machine.

filling the containers with liquid or semi-liquid substances at a filling station of the machine, said filling station being at least partially enclosed by said sterile tunnel, and

providing an excess pressure of sterile gas to the nozzles during at least the filling operation.

According to a still further aspect of the invention, there is contemplated a method of producing sterile liquid or semi-liquid filled packages comprising the steps of passing a plastic film web from a supply thereof successively through a sterilization bath and heating, forming, filling, closing and cutting stations and providing an excess pressure of sterile gas to at least some of said stations during operation of the machine, said sterile gas being supplied through spaced nozzles through which an atomized disinfectant is also supplied before machine operation.

The advantages of the present invention include the feature that all the machine parts which are surrounded by the sterile tunnel are thoroughly disinfected before the machine comes into operation. A further advantageous feature is that all machine parts in the tunnel, in addition to the web of film leaving the bath, are kept sterile by the excess pressure of sterile air in the sterile tunnel.

The exceedingly simple arrangement of the sterilization means makes it possible for the spraying of the disinfectant mist and the formation of the excess pressure of sterile air in the sterile tunnel to take place consecutively and without interruption. The duration of the disinfectant mist treatment depends on the contents of the disinfectant container which is connected by a branch to the main pipe. Depending on the length of any interruption of operation, which may be caused by repairs and modifications, it will be necessary to again disinfect the inside of the tunnel before the machine resumes operation. This takes place simply in that the empty disinfectant container is filled up-again or the stop valve of the full container is opened.

Thus, by means of the same pipe, the same distributor and the plurality of nozzles connected thereto, two processes serving different purposes are carried out, which in collaboration with the treatment bath for the web of film ensure an optimum sterilization of the individual packages.

The invention will now be described by way of example with reference to the drawings in which:

FIG. 1 schematically illustrates the general arrangement of one embodiment of packaging machine according to the present invention, and

FIG. 2 is an enlarged schematic view of that section of the machine with the sterile tunnel.

in the illustrated embodiment, a web 2 of synthetic film is guided froma supply roller 1 over guide rollers 3 and through a sterilization bath 4 in an enclosed space. The fluid adhering to the web 2 is completely removed in the closed space by a suction device 5, a drier 6 and a film-heater 8, which film-heater is screened from the outside by a side wall 7. The web 2, which is made plastic by the film-heater 8, then reaches the shaping station 9,- in which shaping station a plurality of interconnected containers are formed simultaneously. The containers then pass beneath a metering device 10 having a number of filling nozzles corresponding to the number of containers produced in one forming operation. in the schematic illustration of FIG. 2, three containers are formed in each operation. These filling nozzles project into a sterile tunnel 11 consisting of a protective hood and trough to fill the containers.

The closing and sealing of the containers by means of a web 13 of synthetic material or light metal film drawn off a roller 12 occurs at a closing station 14 and a sealing station 15. The web 13 is drawn through a sterilization bath l6, dried and then positioned on the edge of the container by closing tools and subsequently sealed thereto. On sealing, the inside of the closed package is protected against any admission of bacteria and the sterile tunnel 11 thus terminates at the sealing station 15. The packages are then cut out of the web 2 at the cutting station 17 and thus separated. The remaining film is then wound onto a roller 18.

The sterile tunnel 11 extends along the machine from the end of the shaping station 9 to the beginning of the sealing station l5. in this region, in which considerable tension occurs due to web deformations, the web 2 does not always lie flat on the guiding and treatment parts of the machine. Moreover, the filling nozzles of the metering device are located inside the tunnel 11. Consequently, contamination of the packages by the other machine structures would be possible in this region but for the novel sterile tunnel arrangement of the present invention.

On both sides of the sterile tunnel 11, at the level of the web 2, spaced nozzles 19 are provided. The nozzles 19 on one side are staggered with respect to the nozzles 19 on the other side to enhance the spraying pattern. The entire space enclosed by the sterile tunnel 11, Le. the space between the trough and the protective hood is completely covered by the nozzles 19. At each side of the tunnel, the respective nozzles 19 are connected by respective connecting pipes 20 to a distributor or manifold 21 to which sterile air is supplied from a sterile filter 23 via a central pipe 22. A compressor (not shown) supplies the air to the filter and/or central pipe under pressure. A feed pipe 24 operating according to the injector principle opens into the central pipe 22 and is connected to a container 25 containing a liquid disinfectant. The flow of sterile air through central pipe 22 draws or sucks the liquid disinfectant from feed pipe 24 into pipe 22 where the air and liquid are intermixed and then communicated to the nozzles by way of the manifold 21.

A cover 11a for the film web 2 is disposed in front of the sterile tunnel 11, extending from the guide rollers 3 across the heating unit 8 to the shaping station 9. In this region under cover 11a, re-infection of the film web sterilized by the disinfecting bath is prevented by an excess pressure of sterile air. A well 16a is provided for covering the film web 13 as it passes between sterilizing bath 16 into the sterile tunnel 11. This well 16a is, like the interior of tunnel 11,.disinfected by the spray nozzles 19 and, after termination of the disinfectant spraying step, is under an excess superatmosphe ric sterile air pressure. Cover 11a and well are not shown in-FIG. 2 so as to more clearly illustrate the sterile tunnel configuration with respect to the containers passing therethrough.

The method of operation is as follows:

Firstly, at the end of a production run the sterile tunnel 11, and the metering device 10 are mechanically cleaned. Before the machine is again set in operation, the tunnel 11 is sterilized by atomization of the liquid disinfectant passing through nozzles 19 with the sterile gas or air. It has been shown by tests that intensive atomization sufficient for substantially disinfecting and sterilizing all machine parts enclosed by the sterile tunnel ll, including the guide members for conveying the film, can be achieved with approximately one litre of disinfectant for a tunnel 11 having a length of 2,600 mm, a width of 240 mm and a height of 50 mm. This intial disinfecting process could be completed in about 10 minutes, and involves the sterile air from the sterile filter 23 being supplied, through the central pipe 22 with simultaneous mixing with the liquid in the feed pipe 24, to the distributor 21 and from there to the individual nozzles 19. The atomization is completed as soon as the liquid is used up or-as soon as the flow to the feed pipe 24 is interrupted by means of a stop valve (not shown). On the other hand, there is no interruption of the sterile air flow which is now supplied in pure form via the central pipe 22 and the distributor 21 to the individual nozzles 19 to produce an excess pressure in the sterile tunnel l1 and simultaneously act as an airbrush on the remaining liquid of of the mist. After intensive sterilization the liquid flows from the machine parts into the trough and from there into the outlet. The excess pressure of sterile air in the sterile tunnel ll prevents bacteria from entering through leaks in the sterile tunnel 11, particularly at the ends of the tunnel 11 where the web 2 enters and leaves.

The detailed structure and operation of certain individual components of the machine, such as the heating, forming, filling, closing and cutting stations, have not been included in thisdescription so as not to obscure the basic features of the present invention. It is to be understood that stations for carrying out these individual operations are known to those skilled in the art to which the invention pertains.

While we have shown and described one embodiment in accordance with the present invention, it is to be clearly understood that the same is susceptible to numerous changes and modifications as will be apparem to one skilled in the art. We, therefore, do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the present invention.

What we claim is:

1. Apparatus for producing sterile liquid or semiliquid filled packages comprising: supporting means for supporting a supply of synthetic film web, sterilization bath means for sterilizing the web being supplied from the supporting means, heating means for heating the web after it passes through the the sterilization bath means, forming means for forming containers in the web after it passes through the heating means, filling means for filling the container, closing means for closing the containers, cutting means for cutting said containers out of said web, a sterile tunnel enclosing at least some of said heating, forming, filling closing and cutting means, a plurality of spaced apart nozzles arranged for spraying into said tunnel, sterile gas supply means for supplying sterile gas to said nozzles such that an excess pressure of sterile gas in maintained in said tunnel during operation of the apparatus, and liquid disinfectant supply means for supplying liquid disinfectant to said nozzles for disinfecting the inside of the tunnel.

2. Apparatus according to claim I, wherein the sterile gas supply means includes: a sterile filter, a main pipe connecting said filter to a distributor, and a plurality of branch pipes each connecting a respective nozzle to said distributor; and wherein said liquid disinfectant supply means includes a container for holding the liquid disinfectant and a feed pipe opening into said main pipe, said feed being constructed with respect to said main pipe so as to operate according to the injector principle in communicating the fluid disinfectant to said main pipe in response to the flow of sterile gas through said main pipe.

3. An arrangement for disinfecting and sterilizing structures enclosed by a sterile tunnel on a machine of the type which produces a plurality of sterile liquid or semi-liquid filled packages from a synthetic film web; said arrangement comprising: nozzle means positioned for spraying into said tunnel, sterile gas supply means for supplying sterile gas to said nozzle means such that an excess pressure of sterile gas may be maintained in said tunnel during operation of the machine, and liquid disinfectant supply means for supplying liquid disinfectant to said nozzle means for disinfecting the inside of the tunnel prior to initiation of operation of the machine.

4. An arrangement according to claim 3, wherein the sterile gas supply means includes: a sterile filter. a main pipe connecting said filter to a distributor, and a plurality of branch pipes each connecting a respective nozzles to said distributor; and wherein said liquid disinfectant supply means includes a container for holding the liquid disinfectant and a feed pipe opening into said main pipe, said feed pipe being constructed with respect to said main pipe so as to operate according to the injector principle in communicating the fluid disinfectant to said main pipe in response to the flow of sterile gas through said main pipe.

5. A method of producing sterile liquid or semi-liquid filled packages in a machine comprising the successive steps of:

supplying an atomized disinfectant to portions of said machine by way of nozzles arranged in a sterile tunnel enclosing said portions,

forming a plurality of containers from a synthetic film web at a forming station of the machine,

filling said containers with liquid or semi-liquid substances at a filling station of the machine, said filling station being at least partially enclosed by said sterile tunnel, and

providing an excess pressure of sterile gas to said nozzles during at least said filling operation.

6. A method according to claim 5, wherein the step of supplying the atomized disinfectant includes:

placing liquid disinfectant in a reservoir located adjacent to and in communication with a feed pipe for the sterile gas, and

passing the sterile gas through said feed pipe at a velocity and pressure sufficient to suck the liquid disinfectant of the reservoir and to interrnix the disinfectant with the sterile gas on its way to the nozzles.

7. A method according to claim 6, wherein the step of supplying the atomized disinfectant is substantially completed before the forming and filling steps are commenced by starting the machine.

8. A method according to claim 7, wherein the forming and filling steps are continuously repeated after the machine is started, and wherein the step of providing an excess pressure of sterile gas continues during operation of the machine.

9. A method according to claim 6, wherein said sterile gas is air, and wherein said air is passed through a sterilizing filter before entering said feed pipe.

10. A method according to claim 5, further comprising the steps of:

passing said film web through a sterilization bath and a heating station prior to the step of forming, closing said containers at a closing station after the filling step, and

cutting said containers out of said web at a cutting station after the closing step.

1]. A method according to claim 10, wherein said sterile tunnel extends over those portions of the machine betweenthe forming and closing stations, and wherein said nozzles extend over the entire length of said tunnel.

12. Apparatus for producing sterile liquid or semiliquid filled packages comprising:

supply means for supplying container making material,

forming means for forming containers from the container making material,

filling means for filling the containers,

closing means for closing the containers,

a sterile tunnel enclosing at least some of said forming, filling, and closing means,

a plurality of spaced apart nozzles arranged for spraying into said tunnel,

sterile gas supply means for supplying sterile gas to said nozzles such that an excess pressure of sterile gas is maintained in said tunnel during operation of the apparatus,

and liquid disinfectant supply means for supplying liquid disinfectant to said nozzles for disinfecting the inside of the tunnel.

13. Apparatus according to claim 12, wherein the sterile gas supply means includes: a sterile filter, a main pipe connecting said filter to a distributor, and a plurality of branch pipes each connecting a respective nozzles to said distributor; and wherein said liquid disinfectant supply means includes a container for holding the liquid disinfectant and a feed pipe opening into said main pipe, said feed pipe being constructed with respect to said main pipe so as to operate according to the injector principle in communicating the fluid disinfectant to said main pipe in response to the flow of sterile gas through said main pipe.

14. Apparatus according to claim 12, wherein said sterile tunnel is a closed tunnel which extends continuously from said forming means to said closing means and which encloses said filling means and at least portions of each of said forming means and said closing means. and wherein said nozzles are spaced substantially uniformly from one another along the length of the tunnel.

15. Apparatus according to claim 13, wherein said sterile tunnel is a closed tunnel which extends continuously from said forming means to said closing means and which encloses said filling means and at least portions of each of said forming means and said closing means. and wherein said nozzles are spaced substantially uniformly from one another along the length of the tunnel.

16. Apparatus according to claim 14, wherein alternate ones of said nozzles along the length of the tunnel are arranged at opposite sides of the tunnel for spraying in respective opposite directions.

17. Apparatus according to claim 15. wherein alternate one of said nozzles along the length of the tunnel are arranged at opposite sides of the tunnel for spraying in respective opposite directions.

18. Apparatus according to claim 13, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant to said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterrupted follows termination of supply of liquid disinfectant thereto.

19. Apparatus according to claim 15, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant tosaid main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterruptedly follows temtination of supply of liquid disinfectant thereto.

20. Apparatus according to claim 2, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant to said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterruptedly follows termination of supply of liquid disinfectant thereto.

21. Apparatus according to claim 2, wherein said sterile tunnel is a closed tunnel which extends continuously from said forming means to said closing means and which encloses said filling means and at least portions of each of said forming means and said closing means. and wherein said nozzles are spaced substantially uniformly from one another along the length of the tunnel.

22. Apparatus according to claim 21, wherein alternate ones of said nozzles along the length of the tunnel are arranged at opposite sides of the tunnel for spraying in respective opposite directions.

23. Apparatus according to claim 22, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant of said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterruptedly follows termination of supply of liquid disinfectant thereto.

24. Apparatus according to claim 2, wherein said closing means includes means for supplying a second synthetic film web through a sterilization bath to a position where said second web is cut and portions thereof used to close the filled containers.

25. Apparatus according to claim 23, wherein said closing means includes means for supplying a second synthetic film web through a sterilization bath to a position where said second web is cut and portions thereof used to dose the filled containers.

0 l 0 Q i

Claims (25)

1. Apparatus for producing sterile liquid or semi-liquid filled packages comprising: supporting means for supporting a supply of synthetic film web, sterilization bath means for sterilizing the web being supplied from the supporting means, heating means for heating the web after it passes through the the sterilization bath means, forming means for forming containers in the web after it passes through the heating means, filling means for filling the container, closing means for closing the containers, cutting means for cutting said containers out of said web, a sterile tunnel enclosing at least some of said heating, forming, filling closing and cutting means, a plurality of spaced apart nozzles arranged for spraying into said tunnel, sterile gas supply means for supplying sterile gas to said nozzles such that an excess pressure of sterile gas in maintained in said tunnel during operation of the apparatus, and liquid disinfectant supply means for supplying liquid disinfectant to said nozzles for disinfecting the inside of the tunnel.

2. Apparatus according to claim 1, wherein the sterile gas supply means includes: a sterile filter, a main pipe connecting said filter to a distributor, and a plurality of branch pipes each connecting a respective nozzle to said distributor; and wherein said liquid disinfectant supply means includes a container for holding the liquid disinfectant and a feed pipe opening into said main pipe, said feed being constructed with respect to said main pipe so as to operate according to the injector principle in communicating the fluid disinfectant to said main pipe in response to the flow of sterile gas through said main pipe.

3. An arrangement for disinfecting and sterilizing structures enclosed by a sterile tunnel on a machine of the type which produces a plurality of sterile liquid or semi-liquid filled packages from a synthetic film web; said arrangement comprising: nozzle means positioned for spraying into said tunnel, sterile gas supply means for supplying sterile gas to said nozzle means such that an excess pressure of sterile gas may be maintained in said tunnel during operation of the machine, and liquid disinfectant supply means for supplying liquid disinfectant to said nozzle means for disinfecting the inside of the tunnel prior to initiation of operation of the machine.

4. An arrangement according to claim 3, wherein the sterile gas supply means includes: a sterile filter, a main pipe connecting said filter to a distributor, and a plurality of branch pipes each connecting a respective nozzles to said distributor; and wherein said liquid disinfectant supply means includes a container for holding the liquid disinfectant and a feed pipe opening into said main pipe, said feed pipe being constructed with respect to said main pipe so as to operate according to the injector principle in communicating the fluid disinfectant to said main pipe in response to the flow of sterile gas through said main pipe.

5. A method of producing sterile liquid or semi-liquid filled packages in a machine comprising the successive steps of: supplying an atomized disinfectant to portions of said machine by way of nozzles arranged in a sterile tunnel enclosing said portions, forming a plurality of containers from a synthetic film web at a forming station of the machine, filling said containers with liquid or semi-liquid substances at a filling station of the machine, said filling station being at least partially enclosed by said sterile tunnel, and providing an excess pressure of sterile gas to said nozzles during at least said filling operation.

6. A method according to claim 5, wherein the step of supplying the atomized disinfectant includes: placing liquid disinfectant in a reservoir located adjacent to and in communication with a feed pipe for the sterile gas, and passing the sterile gas through said feed pipe at a velocity and pressure sufficient to suck the liquid disinfectant of the reservoir and to intermix the disinfectant wiTh the sterile gas on its way to the nozzles.

7. A method according to claim 6, wherein the step of supplying the atomized disinfectant is substantially completed before the forming and filling steps are commenced by starting the machine.

8. A method according to claim 7, wherein the forming and filling steps are continuously repeated after the machine is started, and wherein the step of providing an excess pressure of sterile gas continues during operation of the machine.

9. A method according to claim 6, wherein said sterile gas is air, and wherein said air is passed through a sterilizing filter before entering said feed pipe.

10. A method according to claim 5, further comprising the steps of: passing said film web through a sterilization bath and a heating station prior to the step of forming, closing said containers at a closing station after the filling step, and cutting said containers out of said web at a cutting station after the closing step.

11. A method according to claim 10, wherein said sterile tunnel extends over those portions of the machine between the forming and closing stations, and wherein said nozzles extend over the entire length of said tunnel.

12. Apparatus for producing sterile liquid or semi-liquid filled packages comprising: supply means for supplying container making material, forming means for forming containers from the container making material, filling means for filling the containers, closing means for closing the containers, a sterile tunnel enclosing at least some of said forming, filling, and closing means, a plurality of spaced apart nozzles arranged for spraying into said tunnel, sterile gas supply means for supplying sterile gas to said nozzles such that an excess pressure of sterile gas is maintained in said tunnel during operation of the apparatus, and liquid disinfectant supply means for supplying liquid disinfectant to said nozzles for disinfecting the inside of the tunnel.

13. Apparatus according to claim 12, wherein the sterile gas supply means includes: a sterile filter, a main pipe connecting said filter to a distributor, and a plurality of branch pipes each connecting a respective nozzles to said distributor; and wherein said liquid disinfectant supply means includes a container for holding the liquid disinfectant and a feed pipe opening into said main pipe, said feed pipe being constructed with respect to said main pipe so as to operate according to the injector principle in communicating the fluid disinfectant to said main pipe in response to the flow of sterile gas through said main pipe.

14. Apparatus according to claim 12, wherein said sterile tunnel is a closed tunnel which extends continuously from said forming means to said closing means and which encloses said filling means and at least portions of each of said forming means and said closing means, and wherein said nozzles are spaced substantially uniformly from one another along the length of the tunnel.

15. Apparatus according to claim 13, wherein said sterile tunnel is a closed tunnel which extends continuously from said forming means to said closing means and which encloses said filling means and at least portions of each of said forming means and said closing means, and wherein said nozzles are spaced substantially uniformly from one another along the length of the tunnel.

16. Apparatus according to claim 14, wherein alternate ones of said nozzles along the length of the tunnel are arranged at opposite sides of the tunnel for spraying in respective opposite directions.

17. Apparatus according to claim 15, wherein alternate one of said nozzles along the length of the tunnel are arranged at opposite sides of the tunnel for spraying in respective opposite directions.

18. Apparatus according to claim 13, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disiNfectant to said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterrupted follows termination of supply of liquid disinfectant thereto.

19. Apparatus according to claim 15, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant to said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterruptedly follows termination of supply of liquid disinfectant thereto.

20. Apparatus according to claim 2, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant to said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterruptedly follows termination of supply of liquid disinfectant thereto.

21. Apparatus according to claim 2, wherein said sterile tunnel is a closed tunnel which extends continuously from said forming means to said closing means and which encloses said filling means and at least portions of each of said forming means and said closing means, and wherein said nozzles are spaced substantially uniformly from one another along the length of the tunnel.

22. Apparatus according to claim 21, wherein alternate ones of said nozzles along the length of the tunnel are arranged at opposite sides of the tunnel for spraying in respective opposite directions.

23. Apparatus according to claim 22, wherein said sterile gas supply means includes means for continuously supplying pressurized sterile gas to said main pipe irrespective of the communication of liquid disinfectant of said main pipe by said feed pipe such that supply of sterile gas to said nozzles immediately and uninterruptedly follows termination of supply of liquid disinfectant thereto.

24. Apparatus according to claim 2, wherein said closing means includes means for supplying a second synthetic film web through a sterilization bath to a position where said second web is cut and portions thereof used to close the filled containers.

25. Apparatus according to claim 23, wherein said closing means includes means for supplying a second synthetic film web through a sterilization bath to a position where said second web is cut and portions thereof used to dose the filled containers.

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