The present invention relates to a device for the shaping, filling and sealing of containers of flexible and soft laminar material, which comprises a container preshaping station, followed by a shaping and filling chamber; a container sealing station and a container unloading station.

The invention also relates to a procedure for the shaping, filling and sealing of containers of flexible and soft material.

There is a wide variety of containers on the market that contain products that must be packed in sterile conditions, such as, for example, liquid foodstuffs such as fruit juices, milk, etc. For this purpose, the devices for filling containers have been adapted so that they can also operate in sterile conditions. What is generally done is to keep all the stations of the packing devices in sterile conditions, starting by sterilizing the container.

In devices wherein the containers are shaped and filled in line, generally the container shaping station, it is already subjected to sterile conditions. Said operation entails the problem that, in the event of failure in the container shaping station, the sterile conditions are broken, with the consequent losses in time and material involved. For this, there are procedures wherein the sterile area of the device begins in the stage following the container shaping. Examples of this type of device are disclosed in Patents EP 481361 B1, DE 19945500 A1, US 4,992,247 and US 6,120,730.

There are many different variations for creating sterile conditions, such as, for example, high temperatures or the use of sterilizing fluids or solutions such as hydrogen peroxide solutions.

Patent US 4,992,247, discloses a sterilization system comprising a closed circuit which connects a sterile-air sprinkler to spray a mixture of air, hydrogen peroxide and water vapour maintained at 200°F, said sterilization system being adaptable to a device for the shaping, filling with products and sealing of containers. The mixture of hot air and 35% hydrogen peroxide comes into contact with the containers after they are shaped and before being filled with the product. The system provides for the mixture to be recirculated towards the aforementioned sprinkler.

Patent US 6,120,730 discloses an alternative sterilization method for cardboard containers or plastic bottles, especially for containing products which, due to their high acidity level, may be stored without refrigeration. The containers are processed in a shaping, filling and sealing station, and are sterilized once they have been preshaped via successive and alternating stages of hot air injection and gas-phase hydrogen peroxide. The working temperatures needed in the sterilizing tunnel range from between 40°C and 150°C, it being understood that the temperature of hot air injected is between 200°C and 300°C. The high temperatures used, which entail high production costs, are needed to prevent the gas-phase hydrogen peroxide from condensing inside the containers. For this same reason, the concentration of gas-phase hydrogen peroxide is kept below 53%.

In all the cases mentioned, the container to be sterilized is of a plastic bottle or aluminized cardboard type. EP1245493 discloses an apparatus for forming, filling and sealing of flexible containers according to the preamble of claim 1. No effective solutions are known for sterilizing containers made of a flexible laminar material, which is folded and generally soldered by thermofusion to shape the container. The present invention forms a proposal to solve the problems raised above and brings numerous advantages to the state of the art.

The device for the shaping, filling and sealing of containers of flexible and soft laminar material, with a container preshaping station, followed by a filling chamber; a container sealing station and an unloading station for filled containers, is characterized by the features according to claim 1.

In an aspect of the invention the temperature in the sterilizing antechamber is equal to or lower than 70°C, and therefore the temperature of the preshaping station, filling tunnel, sealing station and unloading station of the containers is kept at ambient temperature.

According to another characteristic of the invention, the temperature of the sterilizing antechamber is preferably between 40°C and 70°C.

According to another characteristic of the invention, the temperature in the sterilizing antechamber is preferably between 40°C and 70°C.

The device is also characterized in that the pressure in the sterilizing antechamber is greater than the pressure in the preshaping station and lower than or equal to the pressure in the sterile filling tunnel.

According to another characteristic of the invention, the pressure in the sterilizing antechamber is lower than the pressure in the preshaping station and the filling tunnel in sterile conditions.

According to another aspect of the invention, the preshaping station and, at least, the sterile filling tunnel, have means for supplying air which provide a vertical air flow, perpendicular to the direction in which the containers move.

Another characteristic of the invention is that the concentration of gas-phase hydrogen peroxide is equal to or lower than 30,000 parts per million (ppm).

The device according to the invention is also characterized in that the concentration of gas-phase hydrogen peroxide is equal to or lower than 1,500 parts per million (ppm).

The procedure for the shaping, filling and sealing of containers of soft and flexible material being the object of the invention, is characterized by a process according to claim 11.

The procedure being the object of the invention is also characterized in that the container sterilization stage b) is performed at a temperature equal to or lower than 70°C, preferably between a range of 40°C and 70°C, and more preferably between 45°C and 55°C.

The procedure being the object of the invention is also characterized in that in the preshaping stage a), the filling stage c), the sealing stage d) and the unloading stage e), the containers are kept at ambient temperature.

According to another characteristic of the procedure of the invention, the sterile air of the sterilizing antechamber, enriched with hydrogen peroxide, is evacuated into the atmosphere prior to transformation of the peroxide into water and oxygen via catalysis.

The attached drawings illustrate, as a non-restrictive example, a device for the shaping, filling and sealing of containers of flexible and soft laminar material, according to the invention. They also demonstrate the stages of the procedure according to the invention. In said drawings:

Fig. 1

corresponds to a diagram of the device for the shaping, filling and sealing of containers of flexible and soft laminar material according to the invention, wherein the components that characterize it can be seen.

In Fig. 1 is a diagrammatic representation of a device 1, of the type usually used for the shaping, filling and sealing of containers of flexible and soft material (101, 102, 103, 104), and wherein the characteristic parts of the invention are represented. In order to simplify the representation, the device 1 has been shown truncated, not accounting for the usual, known elements used to perform the shaping, filling and sealing of the containers. It can be seen how the device 1 has a container preshaping station 2, followed by a filling chamber 3; a container sealing station 4 and a container unloading station 5. The filling chamber 3 is divided into two clearly-defined areas, the first consisting in a first sterilizing antechamber 6 and the second in a filling tunnel 7 in sterile conditions.

In the preshaping station 2, the flexible and soft laminar material 15 coming from a reel 16, is folded and cut accordingly to form a preshaped container 101, which defines a cavity suitable for receiving the product. Specifically in this area of the device 1, the laminar material 15 of the base 12 and walls 11 of the containers 101 is soldered by using pressure and heat, consequently forming the watertight cavity which will be filled with the produce in question in the filling tunnel 7 in sterile conditions. In the preshaping station, means for supplying air 91 are foreseen, which provide a flow (F) of air, vertical and perpendicular with respect to the direction (G) in which the containers 101 move.

In the case represented, the sterilizing chamber 6 contains nozzles 8 for injecting, inside the preshaped containers 101 from the preshaping station 2, hot sterile air and gas-phase hydrogen peroxide. Sterile containers 102 are produced in this operation. In Fig. 1, three nozzles 8 are shown. The first and third nozzles 81, 83, inject air inside the preshaped containers 101 from the preshaping station 2, to form the sterile containers 102. Said air, shown by a dotted arrow (H), is drawn from the atmosphere and filtered by conventional filters 18, such as HEPA filters, and is then heated by normal heating means 17, such as, for example, an electrical resistance. The nozzle 82 injects gas-phase hydrogen peroxide inside the preshaped containers 101, with a concentration that varies according to the relative humidity and temperature of the sterilizing antechamber 6.

PHV-type ("Vaporized Hydrogen Peroxide) equipment 24, by STERIS, is used to inject hydrogen peroxide gas which, via specific sensors, not shown here, sends humidity and temperature data to a control terminal which, in accordance with said data, carries out the order to inject hydrogen peroxide in non-saturated gas conditions. For this, ambient air is drawn beforehand, which is dehumidified in a drier 19.

The temperature inside the sterilizing antechamber 6 is between 40°C and 70°C, and preferably between 45°C and 55°C. Said temperature is what comes from the sterile air injected by the nozzles 81 and 83.

The combined effect of the temperature from the soldering equipment used in the preshaping station 2 and the hot air injected from the sterilizing antechamber 6, mean that the antechamber 6 can work up to a range of temperatures of up to 70°C, while also ensuring that the containers 102 are sterilized and made watertight. This is a very important aspect because, in a container type such as the one described, the folded areas of material are critical areas for contamination. Due to the sequence of hot air injection, followed by gas-phase hydrogen peroxide injection, and finally another hot air injection, condensation of the gas-phase hydrogen peroxide is prevented and is eliminated from the inside of the containers 102.

As a consequence of this combined effect of soldering temperature and sequence of injections, the preshaping station 2, the filling tunnel 7, the sealing station 4 and the unloading station 5 of the containers, can be kept at ambient temperature without compromising the organoleptic qualities of the product.

The sterilizing antechamber 6 has an evacuating device 20 which comprises a hydrogen peroxide catalyst which transforms the residual hydrogen peroxide in the antechamber 6 into water and oxygen, which can be released into the atmosphere.

As can be seen in Fig. 1, the filling tunnel in sterile conditions 7, the sealing station 4 and the unloading station 5 have, like the preshaping station 2, means for supplying air 92. These means 92 provide a flow (F) of sterile air, vertical and perpendicular with respect to the direction (G) in which the containers 103 move in the filling tunnel 7, creating in this way a curtain of air which hinders the entry of any particles inside the antechamber of the filling tunnel 7. Added to these means for supplying sterile air 92, is that the resulting pressure in the sterilizing antechamber 6, in the filling tunnel 7 and in the sealing 4 and unloading stations 5 of the containers, is greater than the pressure in the preshaping station 2. More specifically, the pressure in the antechamber 6 is greater than the pressure in the preshaping station 2, but less than the pressure in the adjoining filling tunnel 7. In this way, any particle from the preshaping station 2 is prevented from entering the antechamber 6 and, at the same time, sterile air from the supply means 92 provided in the filling tunnel 7, enters the sterilizing antechamber 6, ensuring a sterile atmosphere. Obviously, the pressure in the different stations can be regulated in accordance with the pressure of the atmosphere.

Although in the case represented, the sealing station 4 and the unloading station 5 have means for injecting sterile air (F), in the same way as the filling tunnel in sterile conditions 7, there is the non-exclusive possibility that the sealing 4 and unloading stations 5 have other methods for ensuring a sterile atmosphere, such as ultraviolet radiation lamps, or any other method suitable for sterilizing.

The filling nozzles 21 are represented diagrammatically in the filling tunnel in sterile conditions 7. Once filled with a product, the containers 103 are transported to the sealing station 4 which is obviously also sterilized. In the case shown, sealing of the containers is done via heat fusion and pressure on the material on the upper part 13 of the filled containers 103 and a sterile lid 14 is also fitted from a dispenser 22. There are obviously alternative ways of sealing the containers 103 consisting in, for example, sealing by heat fusion and pressure on the material without a lid 14. Other sealing methods are also considered wherein the lid 14 is added before reaching the sealing station 4.

Once sealed, the containers 104 are collected in the unloading station 5 and taken to a normal packing station 23 for subsequent distribution.

With a device 1 according to the invention, which comprises a first container sterilizing antechamber 6 and a filling tunnel in sterile conditions 7, containers of soft and flexible material 101, 102, 103, 104 can be manufactured at an average rate of 60 cycles per minute, more than one container being processed in each cycle. As is usually the case in manufacturing this type of container 101, 102, 103, 104, each cycle of preshaping, first injection of sterile air, injection of hydrogen peroxide gas, filling, etc., runs at a rate of, for example, two containers 101, 102, 103, 104 per cycle. Said parameters correspond to the usual ones in this type of device and manufacturing process, in such a way that the added characteristic of sterilizing the containers 101, 102, 103, 104 does not affect their production.

Obviously, this technical solution of providing a first sterilizing antechamber 6 and a second filling tunnel in sterile conditions 7 which allows sterilization at relatively low temperatures and with controlled concentrations of gas-phase hydrogen peroxide, applies to any device 1 for the shaping, filling and sealing of containers of soft and flexible laminar material without moving away from the object of the invention. It can thus be considered for use with devices 1 and procedures that operate at different rates or which are complemented by a variety of accessories for improving the shaping, filling or sealing of containers 101, 102, 103, 104.

Prior to its use for the shaping, filling and sealing of containers of soft and flexible laminar material, the device 1 according to the invention must be completely conditioned and sterilized in those areas or regions requiring a sterile atmosphere. For this, the device must be washed according to the standard procedures, using, for example, disinfectant solutions and steam, but also, because it has many nozzles 8 for injecting gas-phase hydrogen peroxide, this gas is also used for the prior sterilization of the device stations which must be kept in sterile conditions during operation, which includes, the sterilizing antechamber 6, the filling tunnel 7 and the sealing station 4.

A variation of the present invention, consists in a device 1 made up by a filling chamber 3, a container sealing station 4 and an unloading station 5, and is a device 1 without the preshaping station 5, but wherein the filling chamber 3 consists in a first sterilizing antechamber 6 and a second filling tunnel in sterile conditions 7. In this type of device 1, in fact, it is relatively easy to separate the different modules or stations.

In this variation of the device 1, without a preshaping station 2 and applicable for containers of soft and flexible material 101 which are already shaped, provision is made for the pressure in the sterilizing antechamber 6 to be negative or lower than ambient pressure, while the pressure in the filling tunnel in sterile conditions 7 has a positive value or one greater than atmospheric pressure. This relationship between pressures in the different chambers of stations ensures that the gas-phase hydrogen peroxide injected in the sterilizing antechamber is not lost by the previous part of the device 1, which would cause deterioration via its oxidation. In addition, in this way, the device 1 made up by a filling chamber 3, a container sealing station 4 and an unloading station 5, can be situated in an adjacent position in any area or room, ensuring that the hydrogen peroxide will be taken to the evacuating catalyser device 20 and will not be leaked in the room wherein the device 1 is located.

Although this pressure relationship may itself be applied to a device 1 which comprises a preshaping station 2, this causes the pressure in the sterilizing antechamber 6 to be lower than atmospheric pressure, the preshaping station 2 being joined to the sterilizing antechamber 6 acting as a means of protection against leakage of the gas-phase hydrogen peroxide into the room and, therefore, while it ensures that the pressure in the filling tunnel in sterile conditions 7 is higher than that in the sterilizing antechamber 6, this makes no difference if the pressure in the antechamber 6 is or is not lower than the atmospheric pressure in the preshaping station 2.