MXPA99009650A - System for blow-molding, filling and capping containers - Google Patents

Abstract

A process and apparatus (10) for blow-molding (12), sterilizing (13), filling (14) and capping (15) plastic containers (C) under conditions of positive control in a close-coupled, compact machine (10) to enhance operational efficiency.

Description

SYSTEM FOR MOLDING BY BLOWING, FILLING AND FILLING CONTAINERS FIELD OF THE INVENTION The present invention relates to blow molded plastic containers, and more specifically, the present invention relates to a method and apparatus for blow molding, filling and covering plastic containers continuously.

BACKGROUND OF THE INVENTION It is known to manufacture plastic containers for use in the so-called hot filling process by injection molding of plastic preforms, such as PET, as well as blow molding the preforms in a mold cavity. After molding, the resulting packages are discharged from the mold and packaged for transport to another site to be filled with a beverage, for example juice at an elevated temperature. After filling, the containers are covered and allowed to cool to room temperature to distribute them to the final consumer. This same basic procedure is used to fill containers with other edible and inedible liquids, such as salad oil and shampoo; some of these other liquids are filled at room temperature.

It is very common for the preforms to be injection molded in one place and transported to another place where the containers are produced by blowing. In the blowing place, the preforms usually enter a single line to a feeding mechanism that transfers the preforms to a conveyor belt that separates them from one another and advances them in an open circuit path through the conveyor belt. a preheating oven. In the preheating furnace, the preforms are heated to a predetermined temperature by various means, such as radial heaters. After the preforms are heated to the desired temperature, usually close to the glass transition temperature (Tg) of the particular plastic form from which the preform is molded, the latter is transferred to a mold cavity. by blowing. Once in the mold cavity by blowing, the preform is blown by compressed air in the shape of the cavity of the mold, while preferably being subjected simultaneously to axial stretching to effect the biaxial orientation of the container; all this known in the art. After a brief period of stay in the mold, the resulting blown container is unloaded from the mold to be packaged and transported to another location to effect the filling. The filling location can be at a completely separate plant location or can be connected to the blow molding equipment by means of a belt-type conveyor belt, such as where blow molding occurs at a plant location and filling in another location on the same floor.

Belt-type belt conveyors are commonly used to move containers from one location to another in the plant, particularly when it comes to non-carbonated liquids. In systems for filling carbonated liquids, containers are almost always transported by the top of the neck. It is also known to use chain-type conveyor belts in the preheating furnace to secure the preforms at the neck ends when they are being heated. Sidel of Le Havre France, manufactures a rotating preform transfer device that holds the preheated preforms around the collars and transfers them to the mold by blowing. The device rotates very similar to a star wheel, about a vertical axis, but has claw-like clamping elements that hold the preform around the neck cap and make it advance in an arched path and a similar fastener related to the blow mold. The fastener in the rotary transfer device is designed to release the preform only after the mold holder has already grasped the preform. As a result, the preform is always under positive control as it transits through the preheating furnace and the blow molding apparatus. It has been discovered that in operation, said apparatus is of particular reliability. In an aseptic filling operation, after the package is blown from a preform, it is blown out of the mold to sterilize, fill and cap it. It is a conventional practice to load empty blown containers on a conveyor belt that takes them to another location in the plant to sterilize them, fill them and cover them. In said location, the containers, in the beginning, are separated from the conveyor belt by various means, for example a screw conveyor belt for transferring between guide channels towards a star wheel that moves the containers through various paths passing through stations. of sterilization, filling and capping. This equipment is known in the art. A major problem with the previous approach in the production of blow molded containers, filled and covered, lies in the inefficiencies related to the transfer of empty containers from one conveyor belt to another. During the transfer process, the packages tend to agglomerate in the region of the transfer of the screw conveyor belt towards a guide channel and a star wheel, in particular, when the empty containers are held by their bodies, which are deformed with ease, so it is necessary to interrupt the entire line to clear all the agglomeration. Considering the high production speed associated with filling operations and modern packaging manufacturing, interruptions, even if they are only half an hour, can be expensive for the plant operator. In addition, in an environment in which containers are also sterilized before being filled, other inefficiencies occur due to the need to enter a sterile environment to clear an overcrowding, and for the time necessary to re-sterilize.

A common technique for the rapid filling of containers with liquids is related to the use of a movable filling nozzle that penetrates the neck of a container and that retracts as the filling continues.

With this technique the foaming is reduced and this facilitates exact filling at a predetermined filling level. Although this technique can be satisfactory in the hot filling of containers, it is not desirable in the aseptic filling, where it is imperative that the filling nozzle does not penetrate the neck of the container in order to preserve the sterilization of the container and the content, as well as to avoid possible reciprocal contamination. When covering full containers, usually, the covers come from a conduit and are taken to apply to the containers when they pass through a cap station. It is known that said equipment tends to agglomerate, so it may be necessary to interrupt the entire line to fix the course of the agglomeration. Sometimes, a full but uncovered container leaves the capping machine and spills the contents, which requires cleaning, not to mention the loss of the product. There have been some attempts to control the application of the covers in the nevases with a certain degree of precision, in an effort to avoid this problem; however, the effectiveness of such equipment is not known. In the prior art, blow molding systems operate in yields over 95%, while filling / capping systems operate between 70-80%. The economic operation required the decoupling of these operations. A system is needed to increase the efficiency of filling / capping. This is true in particular with aseptic operations. In addition to the reliability limitations related to the attempt to integrate unequal elements of machinery, which often produce different companies, in an efficient operation, there is the problem of space limitations in the plant. An apparatus that can blow mold and cover containers in a minimum of space in the plant is very desirable from the point of view of the need for capital and efficiency.

OBJECTS OF THE INVENTION With all of the foregoing in mind, an object of the present invention is to provide a novel method and apparatus for blow molding, filling and capping plastic containers with efficiency. Another object of the invention is to provide an improved method and apparatus for handling the package preforms from the moment they enter the preheating oven until after they have been filled and capped. Another object of the present invention is to provide a unique method and apparatus for blowing, sterilizing, filling and covering containers in a single machine, which can withstand agglomeration, and which can be changed to the various sizes quickly and with minimal loss in the efficiency from the beginning, and that occupies a minimum of space in the plant. As another object, the present invention provides an improved method and apparatus for conserving sterility during filling, and reducing the introduction of oxygen from the product being filled.

BRIEF DESCRIPTION OF THE INVENTION More specifically, in the process of the present invention, a plurality of preforms are advanced in sequence under positive control while they are being preheated in a preheating oven. The heated preforms are transferred under positive control of the oven preheating to a blow mold, where the containers are formed. The blown containers are discharged from the mold by blowing under positive control and subsequently, they are advanced under positive control through filling and capping stations. Upon filling, the containers are tilted in relation to a filling nozzle that remains fixed relative to the container and is maintained on a sterile plane that passes through the upper edge of the container top. Preferably, the blown containers are advanced under positive control through a sterilization station just before filling and covering.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects, features and advantages of the present invention will become apparent from the following description, when combined with the accompanying drawings, in which: Figure 1 is a schematic diagram illustrating the particular equipment useful in practice of the process of the present invention; Figure 2 is a very elongated, somewhat schematic view, taken on line 2-2 of Figure 1; Figure 2A is a plan view taken downwards in Figure 2; Figure 3 is an elevated view, in partial section, taken along the line 3-3 of Figure 1 to illustrate the apparatus in the inclination of the container during filling.

DETAILED DESCRIPTION OF THE INVENTION With reference to the drawings, Figure 1 schematically illustrates in a plan view, the preferred apparatus 10 for practicing the method of the present invention. As illustrated therein, the apparatus 10 includes a series of work stations arranged in a floor plane of a compact, horizontally elongated plant. The apparatus 10 includes a preheating oven 11, a blow molder 12, a sterilizer 13, a filler 14 and a cap 15 that are tightly coupled in a fully enclosed and integrated unit. As will be shown, the injection molded preforms are admitted in the apparatus 10 in an upflow location 10a (lower left in Figure 1), and the caps are admitted in the apparatus 10 in a downflow location 10b (upper left) in figure 1) adjacent to an exit port 10c (upper part) where the filled and capped containers leave to be packaged and transported to the final consumer. The preheating furnace 11 contains a chain type conveyor 11 to which the preforms are mounted by means of a star wheel 16 and a guide channel 16a and are transported separately in an open circuit path, first in one direction, and then in the opposite direction towards the blow molding 12. In the preheating furnace 11 the preforms are heated by various known techniques, such as radial heaters, to raise the temperatures to a temperature suitable for blow molding (e.g., the transition temperature of glass, Tg). The preheating furnace 11 is connected to a blow molder 12 by an open hole 20 through which the heated preforms pass. The preforms are released from the conveyor belt of the preheating furnace 1 1a and transferred to the blow molder by a positive clamping transfer wheel 21 disposed between the conveyor belt of the preheating furnace and the blow molder 12. The heated preform is transfers to a blow molded wheel rotating on a vertical axis to blow the preform into the desired shape of the container as the wheel rotates counterclockwise in the blow molder 12. The blow molded containers are discharged of the blow moulder 12 by a positive flow ascending transferring wheel 22 in comparison with the positive flow ascending transfer wheel 21. As described hitherto, the preheating oven 11 and the blow molding 12 They have a design and construction available in the market. A preferred preheating furnace 11 and a blow molding 12 is manufactured by Sidel of Le Havre, France. The blown containers discharged from the blow moulder 12 had hitherto been transferred by conventional conveyor belts to other locations in a plant to be sterilized, filled and capped or packaged and transported to other locations in the plant. In accordance with the present invention, the blow molding 12 is directly connected to a horizontally elongated enclosure C containing the sterilizer 13, the filler 14 and the capper 15. The blown containers are transferred under positive control conditions, not only through the preheating furnace 11 and the blow molding 12, but also through the sterilization, filling and capping stations in flow. descending in a common enclosure C which is tightly coupled to a blow molding 12. Up to here, the sterilization, filling and capping enclosure C is connected to the blow molding 12 by a port 23 through which the blown containers are first transferred to the sterilizer 13. The sterilizer 13 has a conventional rotating design employing a sterilization rinse, such as a rinse with ozone water to sterilize the interior of the blown containers as they proceed in an arcuate path about a vertical axis. After the container is sterilized and rinsed, it is transferred from the sterilizer, via a star wheel system / positive guide channel 24, 24a, to the filler 14 in the cabinet C. The filler 14 has a conventional rotary design. In it, the sterilized containers advance in an arcuate path on a vertical axis where they are subsequently filled to a predetermined level before being discharged and transferred by another star wheel / positive guide channel system 25, 25a to the capper 15 in the C cabinet. The filled containers advance in an arcuate path on a vertical axis in the capper 15 and after being capped, they are discharged by another star wheel / positive guide channel system 26, 26a. As illustrated in Figure 1, after the blown containers exit the blow moulder, they advance in a continuous serpentine path through the sterilization, filling and capping stations under continuous positive control conditions. In the present invention, continuous positive control is effected by holding the preform around the neck cap by a first set of fasteners 30, 31 cooperating with cams and driven pulleys (not shown) to release each preform, only after that a second set of fasteners 32, 33 has held the preform around the neck end NF. See figures 2 and 2a. The fasteners 30-33 have a claw-like construction and are arranged in a separate position relative to the periphery of each positive clamping wheel 16, 21, 22, 24, 25 and 26, the blow molding 12, sterilizer 13, filler 14 and capper 15. The opening and closing of the grippers 30,33 and the interaction of the gear of the star wheel are synchronized with the rotation of the positive transfer wheels to ensure the continuous positive assurance of the neck cap on the blowing, sterilizing, filling and capping operations. In addition to the positive control of the closures of the necks of the containers as they progress through the apparatus 10, the present invention contemplates the positive control of the caps in the capping machine 15 in a manner that ensures that a lid will not be discharged if there is no a container that receives it. So far, there is a means D for detecting the absence of a neck cap of the container at a particular location after coming under a positive control in the apparatus 10. For example, said location may be in the preheating oven 11, or at some other downstream location, as illustrated, after positive control of the preform. After the absence of a cap from the neck of the container at a particular location has been detected, it is important to determine by electronic means E when the location reaches the capper 15, and to ensure that the cap is not in place at the time a cap would be applied. cover the neck of the neck that is not. Preferably, this is carried out by placing the caps under positive control, before the region between the admission to the cabinet C and the placement in the capper 15. In this way, the whole machine can be emptied simultaneously. For example, if the preforms stop at the portal 10a, correspondingly, the lids stop at the point M, in such a way that the last preform coincides with the last lid on the capper 15. A device for driving caps CS it is used between the location M and the lid sterilizer S in the lid feeding line. The positive control can be carried out by a conveyor belt, wherein each lid is held in a separate cavity with an M mechanism to unload a cavity cover that would be on the filling location corresponding to the location of the neck cap missing in response to an ascending flow of the missing neck auction. This ensures that a lid will not be discharged in the absence of a blown container to receive the lid in the capper 15. The advantage of this is not only to reduce the loss of caps, but also to ensure the absence of lost caps that can jam the mechanisms and result in an interruption of the entire system.

The various articles of the equipment described, include the preheating conveyor belt, the blow moulder, the sterilizer, the filler and the capper, can be controlled by a common energy source through an appropriate mechanism, or can be controlled by separate interconnected motors by means of electrical EC controls designed to synchronize the movement of the various elements of the equipment. This is indicated schematically in Figure 1 by reference numbers 40-50. Cabinet C containing sterilizer, filler and capper excludes unfiltered air outside, except for the regions through which blown containers, lids and filled containers, respectively, enter and exit. The sterilized air flow passes through an upper filter medium that is above the equipment in cabinet C. Appropriate air locks can be provided in these locations, such as air curtains in 10b and 10c, to separate the relatively sterilized environment which is contained in cabinet C of the ambient air. Also, there is an air curtain in port 23 between the blow molding 12 and the cabinet C. Preferably, the entire cabinet C contains on-site spray cleaning equipment, known in the art, for washing equipment locked at the proper intervals. Starting from the above, it would be evident that the present invention provides an efficient method and apparatus for blowing, sterilizing capping and filling containers, wherein the preforms of the containers and the containers blown therefrom, are constantly conserved in positive control throughout the procedure from preheating to capping.

This is achieved by eliminating non-positive transfer points. In the present invention, the positive control is conserved through means that hold each end of the container throughout the process and make it advance in a continuous serpentine path from preheating to capping. By eliminating the screw clamping of the container body by conveyor belts, linear conveyor belts and transfer mechanisms for them, the propensity to agglomeration is eliminated, and the efficiency of the entire process is significantly improved. In addition, efficiency is improved when the caps are also kept under positive control in and through the capper as described. The positive control aspects of the present invention provide the above advantages even when sterilization is not required, but are particularly desirable when sterilization of the package is required, since there is no need to break the asepcia to clear an agglomeration. Often, in the systems of blowing, filling and capping one size is changed from bottle to bottle. In the prior art, this required the change of screw conveyors, star wheels and adjustment guide channels. If the adjustment was not perfect, there were agglomerations at the beginning. Since the positive transfer occurs at the neck end without change NF, a change in size only requires changing the blow molds and restarting the machine 10. In addition, this increases the overall efficiency which is of particular importance in aseptic operations. As used herein, the term "container" is intended to encompass bottles, flasks and similar receptacles for containing fluid materials. In the aseptic filling of a container with a sterilized liquid, it is imperative that the discharge port of the filling nozzle does not break a sterilized filling plane passing through the upper end of the container cap, perpendicular to the central longitudinal axis of the container. The reason for this need is that the penetration through the discharge port of the filling nozzle can compromise the sterility of the filled container due to the possibility that microorganisms can be transferred into the nozzle into the interior of the container finish. Until now, in conventional practice, the filling nozzles enter the top and retract when the container is filled to decrease the foaming of the liquid and accelerate the filling. This practice is anti-ethical for an efficient filling of sterilized containers for sterilized liquids. The foam in the filling can transfer possible contamination from the bottle to the machine to a subsequent bottle; Also, this foam adds oxygen to the filling product. Some products like juice develop oxidation flavors at the moment when oxygen is in the juice. These flavors shorten the shelf life. Therefore, by substantially eliminating the foam, the shelf life of the product is extended with obvious economic benefits.

The present invention overcomes the aforementioned sterilized filling problems and product ventilation and allows effective sterile filling speeds to be achieved. Thus far, as best seen in FIG. 3, the apparatus can tilt a Cx package during filling from a discharge port 100a of the filling nozzle 100 which is held on a sterilized filling plane P. Preferably, the inclination is effected by holding the cap of the neck of the container NF when the container Cx advances in the filling station 14 and, during the filling, continues advancing the inclined container held when the container Cx is loaded with liquid through the top of the neck NF . Preferably, the Cx package advances in a suitable trajectory in a rotary filling machine 14, which is equipped with inclined rails 115a and 115b that tilt the base of the package out radially. A belt conveyor 120 can be found in a portion of the movement path of the container Cx to secure and support the base of the container Cb after it has at least partially filled to release some loads in the neck of the subject container Cn. Also, preferably, the discharge port of the filling nozzle 100a is offset from the central longitudinal axis CL of the container Cx, preferably radially inward of the path of movement of the containers in the filler 14, so that the sterilized liquid flows to the sloped interior surface of the container during filling. In the filling process, the filling nozzle is held fixed relative to the neck of the container and is located on the sterilized plane P while advancing with the container Cx when moving. In this way, the liquid flows at an acute angle relative to the central longitudinal axis of the container CL, causing it to collide with the interior of the container dome and / or side wall, in Ci before hitting the bottom surface of the container Cb. As a result, a significant amount of the liquid fluid energy produced by the foam is dissipated, thereby allowing relatively high filling speeds to be achieved without the need for a penetrating type filling nozzle, and of course, without risking the loss of sterility of the container and the content with which it is filled. In view of the foregoing, it will be apparent that the present invention provides an improved method and apparatus for blowing, filling and clogging blow molded containers in an efficient manner, using compact equipment that occupies a minimum of space in the plant.

Claims (22)

NOVELTY OF THE INVENTION CLAIMS

1. - A method for blow molding, filling and efficiently covering plastic containers blown from preforms having a neck finish, characterized in that it comprises the steps of: advancing a plurality of preforms in sequence under positive control, heating them to same time in an oven 11; transferring the preforms under positive control from the preheating furnace 11 to a blow mold; blowing the preforms into containers in the blow mold; download the blown containers under positive control from the blow mold; and advancing the containers under positive control while filling the containers and filling the filled containers; so that the preforms of the containers and the resulting containers are kept under continuous positive control throughout the process of manufacturing, filling and capping the containers.

2. The method according to claim 1, further characterized in that the positive control is effected by the clamping of the collar of the preform NF continuously throughout the process.

3. The method according to claim 2, further characterized in that the clamping of the positive control includes the steps of securing the neck of the neck NF with a first fastener 30, 31 and before releasing the first fastener 30, 31 of the fastener of the NF collar, securing the NF collar with a second fastener 32, 33.

4. The method according to claim 2, further characterized in that the preforms and the containers blown therefrom are moved in a serpentine path. continues between the preheating step of the preform and the capping step.

5. The method according to claim 4, further characterized in that the continuous serpentine path is in a horizontally elongated chamber C that extends between the location of the blow molding passage and the capping location.

6. The method according to claim 5, further characterized in that it includes the step of sterilizing at least the interior of the containers as they progress in the serpentine path in the elongated chamber in a horizontal manner C.

7.- The compliance procedure with claim 1, further characterized in that it includes the steps of synchronizing the feeding of an occlusion under positive control to a cap of the package at a predetermined capping location during the capping step, detecting the absence of a cap at a predetermined location during the sequence mentioned above, from preheating to filling, and containing the feeding of an occlusion for a predetermined capping location in response to the absence of the capping at the predetermined capping location.

8. - The method according to claim 1, further characterized in that when filling the containers during the advance step, the containers are inclined to cause the filling liquid to enter through the neck of the container without penetrating it and initiate contact with the container without substantial turbulence.

9. The apparatus 10 for blow molding, filling and efficiently covering blown plastic containers from preforms having a neck finish, comprising: the first means for advancing a plurality of preforms in sequence under positive control to the heating them in an oven 11; the means 21 for transferring the preforms under positive control of the preheating furnace 11, and even blow mold; the means for blowing the preforms into containers in the blow mold; the means 22 for unloading the blown containers under positive control from the blow mold; and the second means to advance the containers under positive control by filling the containers and filling the filled containers; so that the preforms of the containers and the resulting containers are kept under continuous positive control throughout the manufacturing process, filling and covering of containers.

10. The apparatus 10 according to claim 9, further characterized in that the positive control is performed by operable fastening means for securing the collar of the preform NF continuously throughout the process.

11. The apparatus 10 according to claim 10, further characterized in that the fastening means includes a first fastener 30, 31 and a second fastener 32, 33, and means for causing the first fastener 30, 31 to release the fastener of the neck NF only after securing the neck of the neck NF with the second fastener 32, 33.

12. The apparatus 10 according to claim 9, further characterized in that the first means for advancing, the means for transferring, the means for blowing, the means for discharging, the second means for advancing are arranged in close spaces in tangential relationship so that the preforms and the containers blown therefrom move in a continuous serpentine path between the preheating means of the preform 11 and the capping means 15.

13. The apparatus 10 according to claim 12, further characterized in that it includes a horizontally elongated chamber C that extends between the blow molding means 12 and the capping means 15, in which the serpentine path is enclosed.

14. The apparatus 10 according to claim 13, further characterized in that it includes means for sterilizing at least the interior of the containers as they advance in the serpentine path in the elongated chamber horizontally.

15. The apparatus 10 according to claim 9, further characterized in that it includes means for synchronizing the feeding of an occlusion under positive control to a container top at a predetermined capping location during capping, means D for detecting the absence of a finish at a predetermined location between the preheating means 11 and the filling means 14, and means for retaining the feed of an occlusion to the predetermined capping location in response to the absence of the capping at the predetermined capping location .

16. The apparatus 10 according to claim 9, further characterized in that it includes a filling nozzle 100 movable with respect to the containers during filling, while remaining fixed on the top of the neck NF, and the means for operably securing the neck cap NF for tilting the containers relative to the filling nozzle 100 to cause the filling fluid to enter the neck cap NF at an angle with respect to the longitudinal axis of the container.

17. In an automated container filling process, further characterized in that the containers having necks Cn with NF closures are delivered in a filling machine 14 having a filling nozzle 100 with a discharge port 100a for loading the containers with a liquid, as they advance one after the other, the improvement comprises the steps of: tipping each container as it advances, and being inclined, make the liquid flow in the container through the neck Cn.

18. The method according to claim 17, further characterized in that during filling, the discharge port 100a of the filling nozzle 100 is maintained on a passage that passes through the upper end of the cap of the container, and perpendicular to the central longitudinal axis of the container.

19. The method according to claim 17, further characterized in that during filling, the discharge port of the filling nozzle 100a is offset from the central longitudinal axis of the container.

20. The method according to claim 17, further characterized in that during filling, the container is held by the neck of the neck NF, by means of which inclines.

21. The method according to claim 17, further characterized in that the interior of the container and the liquid are sterilized before filling, and the filling step is carried out without compromising the sterility of the filled container.

22. The method according to claim 17, further characterized in that the filling nozzle 100 moves, but remains fixed relative to the container during the filling step.