US 3912535 A
Apparatus and method for cleaning and sterilizing a filler pipe used in a packing machine of the type forming a packing tube around the filler pipe, in which, after the filler pipe has been cleaned by a suitable cleaning agent, the inside and outside of the filler pipe is sterilized by passing a sterilizing agent (either gas or vapor) through the filler pipe and along a path such that at least the lower part of the outside of the filler pipe and the associated elements are sterilized.
Description (OCR text may contain errors)
United States Patent Rausr [451 Oct. 14, 1975  APPARATUS AND METHOD FOR THE 2,918,770 12/1959 Stocker 53/180 M CLEANING AND STERILIZING OF FILLER @3523 3:323 3: t 1 5322 11.8 PIPES IN PACKING MACHINES 3,043,318 7/1962 Hi 134/170 X  Inventor; Jan Axel Ingemar Rausr, Lomma, 3,086,336 4/1963 Rausing et a] 5 3/l80 M Sweden 3,164,936 1/1965 Loliger 21 61 x 3,716,083 2/1973 Tuma et a] 134/166 C X Ass1gnee= Tetra Pak International Lund, 3,850,207 11 1974 boliger et a1. 141 90 Sweden  Filed: Aug. 27, 1973 Primary ExaminerS. Leon Bashore Assistant ExaminerRichard V. Fisher [21 Appl' 391555 Attorney, Agent, or Firm-Pierce, Scheffler & Parker  Foreign Application Priority Data Sept. 22, 1972 Sweden 12224/72  ABS CT Apparatus and method for cleaning and sterilizing a  US. Cl 134/22 C; 53/ 180 M; 134/30; filler pipe used in a packing machine of the type form- 134/95; 141/90; 141/91 ing a packing tube around the filler pipe, in which,  Int. Cl. B08B 9/02; B65B 31/00 after the filler pipe has been cleaned by a suitable  Field of Search 134/22 C, 26, 30, 37, 170, cleaning agent, the inside and outside of the filler pipe 134/166 C, 95, 99, 59, 29; 21/56, 61, 77, is sterilized by passing a sterilizing agent (either gas or 121; 53/167, 180 M; 222/148; 141/1, 90, 91 vapor) through the filler pipe and along a path such that at least the lower part of the outside of the tiller  References Cited pipe and the associated elements are sterilized.
UNITED STATES PATENTS 12/1906 Harris 134 170 3 Claims, 2 Drawing Figures U.S. Patent Oct. 14, 1975 Sheet 1 of2 3,912,535
US. Patent 0Ct.14,1975 Sheet2of2 3,912,535
APPARATUS AND METHOD FOR THE CLEANING AND STERILIZING OF FILLER PIPES IN PACKING MACHINES The present invention relates to the technique of packaging and is concerned with a method for the cleaning and sterilizing of filler pipes in packing machines of the type which form a packing tube around a filler pipe and where the packing tube, partly filled with filling material, is divided up into filled and closed packages by means of clamping and sealing jaws arranged underneath the mouth of the filler pipe.
In the technique of packaging, and especially in the packaging of goods susceptible to bacteria, such as for example milk, ever increasing demands are being made of sterile packaging processes. These demands have been further accentuated in the aseptic packing of sterile filling materials, and it has been proposed therefore to use a number of methods to achieve good aseptic conditions in connection with the packaging of such goods.
It is the object of one of the prior methods, for example, to sterilize the inside of the filler pipe without any need for a dismantling and separating of the same for manual washing, and methods exist for filler pipes with circulation facilities. In these filler pipes the circulation washing and sterilizing takes place right down to a base plate arranged during the washing process at the mouth of the filler pipe. A method has also been proposed which supplements a sterile washing of the inside of the filler pipe and which aims at cleaning and sterilizing the outside of the filler pipe without the latter having to be dismantled arid taken apart. In this process the packing tube is used as a washing container and the medium required for cleaning and sterilizing is introduced into the packing tube through a plate inserted in the packing tube and sealed against the tube wall so that it constitutes the base of a cleaning container so formed.
The said method for the cleaning and sterilizing of the outside of the filler pipe has not found any noteworthy practical application, however, since it was found that some uncertainty existed with regard to the fulfilment of the sterility requirement. Since the method in accordance with the invention is intended first and foremost to be used with single-wall filler pipes, the prior methods for the cleaning and sterilizing of the inside of the filler pipe are not used in the present process. Hence only the manual washing alternative remains, possibly combined with some form of circulation washing. The method proposed by the invention should be regarded, however, as constituting a combination of cleaning and then sterilizing the inside and the outside of the filler pipe, or of dismantling and separating the filler pipe for manual washing or cleaning and then sterilizing the filler pipe in its production posi tion by making use of the packing tube as a container.
It was one of the objects of the present invention to bring about a simpler start of the packing machine comprising the filling system and cleaning and sterilizing same. Consideration was also given to time-saving measures. Thus it is possible by the present process to pre-sterilize the inside and the outside of the filler pipe and elements possibly arranged on the lower part of the filler pipe before the start of production with a packing tube formed around the filler pipe. It is a further advantage that the aseptic conditions are not lost in case of an interruption of production or on completion of the filling operation, because the aseptic conditions can be maintained during the interruption and a sterilization of the filler pipe and other exposed elements can be carried out after the interruption. By the use of the present process it becomes possible to develop a higher degree of automation for the lengthy starting of production.
This object can thus be achieved by application of that method in accordance with the present invention. which is characterized in that, after the filler pipe has been cleaned by means suitable for the purpose, and the cleaning agent has been circulated in at least an upper part of the filler pipe and through a circulation line connected thereto, the circulation line is detached from the filler pipe which is then made ready for production, whereupon the packing tube is advanced to a position underneath the filler pipe and is divided up between clamping jaws, the inside and the outside of the tiller pipe being sterilized by a sterilizing agent in gas or vapour form supplied to and guided through the filler pipe as far as its mouth where the gaseous or vaporous agent is hindered from flowing towards that part of the packing tube situated in the region around and underneath the mouth of the filler pipe but rather is directed to flow along the outside of the filler pipe, when at least the lower part of the tiller pipe and elements arranged thereon, such as level-controlling elements and the like, are sterilized.
The invention also relates to a device which is intended to be used in the realization of the method, a filler pipe being provided with a level-controlling element arranged at its lower part, and being surrounded by a packing tube which, belowthe mouth of the filler pipe, is divided up by means of clamping and sealing jaws provided for this purpose. The device is characterized so that the upper part of the filler pipe, during the cleaning and sterilizing operations, communicates either with a supply line for a cleaning agent or with a supply line for a sterilizing agent in gas or vapour form, the upper part of the filler pipe being adapted to be connected to a circulation and return line for the cleaning agent supplied via the supply line, and that an element for directing the gaseous or vaporous agent supplied to the filler pipe is arranged underneath the mouth of the lower part of the filler pipe.
Another characteristic of the device in accordance with the invention is that the directing element arranged underneath the lower part of the filler pipe for the gaseous or vaporous agent is formed of a substantially hemispherical body, so that the filler pipe ends in the concave hollow of the body.
Further advantages and objects of the invention will become clear from the following description of the invention, reference being made at the same time to the enclosed schematic drawings, in which H0. 1 shows mainly supply, discharge and circulation lines to a filler pipe arranged for a cleaning operation, and
4, 5 and is divided up underneath the filler pipe by means of clamping or sealing jaws 3. The lower part 5 of the filler pipe is adapted so that it can be detached from the upper part 4 of the filler pipe, as by a bayonet coupling 6 or some other connecting element. Around the mouth 7 of part 5 of the filler pipe is arranged a hemispherical body 8 so that the filler pipe ends in the concave hollow of the body. A distance above the mouth 7 of the filler pipe a level-controlling element 9 is provided. The level-controlling element 9 is responsive to the level of the filling material present inside the tube, and controls the supply flow of the filling material. The upper end 4 of the filler pipe communicates selectively with a supply line 10 for a cleaning and sterilizing agent, called hereinafter a detergent. The filling material may also be supplied to the filler pipe through line 10 during production. The upper part 4 of the filler pipe also communicates with a supply line 11 for a gaseous or vaporous sterilizing agent. On occasion, the lower part 5 of the filler pipe may be dismantled and a circulation line 12 connected to the bottom of the upper part 4 of the filler pipe as shown in FIG. 1. For this purpose the circulation line 12 has aflexible part 13 which can be connected-to the lower end of upper part 4 of the filler pipe (see FIG. 1). An outlet line 14 is provided for the discharge for the detergent and for passing filling material to the filler pipe of another filling machine which may be coupled to the same system. It is also possible of course, if desired, to pass the gaseous or vaporous sterilizing agent through the outlet pipe 14 to the next packing machine for sterilizing the same. For controlling the various flows from the inlet line 10 through the circulation line 12 and out through the outlet line 14 during the cleaning sequence and the filling sequence, a multi-way valve 15 is provided.
The method for the cleaning and sterilizing of the filler pipe operates in the following manner.
The sterile filling material, such as milk, is supplied during production through the inlet line 10 and is passed through the filler pipe 4, 5 and via its mouth 7 to the inside of the packing tube 1 (see FIG. 2) where the amount of filling material attains a certain level determined by control element 9. During production, see FIG. 2, the inlet line 11 for the gaseous or vaporous sterilizing agent is shut off and the circulation line 12 for the detergent is of course removed. If several packing machines are in production at the same time, the outlet line 14 is open so that the filling material can also pass to the next machine. In the case where the packing machines are coupled in a so called direct installation, the outlet line 14 shall also be open for the last machine in series so that any residue of sterile filling material may be returned to the sterilizer. On the other, if a socalled tank installation is operated, the outlet line 14 of the last machine in the series will have to be closed so as to prevent the filling material from coming into contact with parts of the installation that cannot be sterilized.
When the production has been completed, the packing tube 1 is cut off immediately underneath the lowest of the forming rings 2 as seen in FIG. 1. The lower part 5 of the filler pipe which includes the jet-directing element 8 and the levelcontrolling element 9, is detached for manual washing. The flexible lower part 13 of the circulation line 12 is connected to the lower end of the upper part 4 of the filler pipe by means of coupling device 6, as shown in FIG. 1..A cleaning or washing agent 7 is introduced then through the inlet line 10 to the upper part 4 ofthe filler pipe, the detergent being allowed to circulate through the connected circulation line 12. The detergent is discharged from the system. or taken to some other packing machine. which is ready for a cleaning operation, through the outlet line 14. During the cleaning operation the inlet line 11 for the gaseous or vaporous sterilizing agent is shut off. The detergent may comprise a 2% caustic soda (NaOH) solution. an acid or some other suitable detergent. After the detergent has been allowed to circulate in the system, a possible rinsing of the system may take place by means of hot water or the like. which is made to circulate in the same manner as the detergent.
The cleaning operation is carried out, as mentioned above, after production has been completed or after prolonged'stoppages. Before the packing machine is put into operation again, for example on the morning of the following day, a further washing operation may be carried out. At this time, or directly before the startup of the packing machine, at least one sterilization is carried out after the system has been cleaned of residues of filling material, residues of dirt and the like. For this purpose the circulation line 12 is dismantled from the lower end of upper part 4 of the filler pipe and its lower part 5, which has been washed manually, is attached thereto. Subsequently the packing tube 1 is drawn down to the sealing jaws 3 and a longitudinal joint is obtained, whereupon the packing tube is divided by clamping it between sealing jaws 3.
In the sterilization of the filler pipe 4, 5 a sterilizing agent, such as superheated steam or hot water, is circulated through the filler pipe 4, 5.. Consequently, one position of the multi-way valve 15 shuts off the communication between inlet line 10 and filler pipe 4, 5 and another position shuts off the circulation line 12, which latter line does not have to be sterile and accordingly does not have to be subjected to any sterilization. Through the inlet line 11, however, a gaseous orvaporous sterilizing agent is introduced into the filler pipe 4, 5 which discharges into the jet-directing element 8. The sterilizing agent in gas or vapour form then sterilizes the inside of the filler pipe and also the outside of the same. In the jet-directing element the sterilizing agent is in fact urged .to flow along the outside of the filler pipe, whereby at least the lower part of the latter and elements arranged thereon such as level-controlling elements and the like are sterilized. Moreover in this manner the jet-directing element 8 does not permit the gaseous or vaporous agent to flow directly towards the packing tube at least at that part of the tube which is situated in the areanearest to the mouth 7 of the filler pipe 4, 5. The gaseousor vaporous agent supplied through the inlet line 11 is guided in this case only through and around the filler pipe 4, 5 since the communication through the multi-wayvalve 15 is shut off, and is vented through the upper open portion of the packing tube prior to being shaped by rings 2. In such a form of realization each packing machine has to be provided with a special inlet line 11 for the supply of the sterilizing agent for the respective filler pipes 4, 5.
It will.be understood that the process and the device in accordance with the invention can be modified and supplemented in a number of ways. Thus devices for the automatic opening and closing of the various valve bodies in the multi-way valve may be realized, as well as various modifications of the system of lines shown and described. Furthermore, experiments have shown that, a short stoppage may be carried out by simple throttling of the supply of filling material from the inlet line without any extraneous flavour or other detrimental alteration occurring in the filling material. It was possible thus to continue production without having to carry out any kind of washing and/or sterilizing of the filler pipe. The invention, therefore, is not limited by the embodiments shown and described, but only by the following patent claims.
1. A method for cleaning and sterilizing a filler pipe of a packaging machine in which the filler pipe includes a lower portion separable from an upper portion thereof and includes fluid withdrawing means detachably connectable to the lower end of the upper portion of the filler pipe when the lower portion thereof is removed therefrom, said machine including means for forming a longitudinal tube of a packaging material to surround the lower end of the filler pipe and means for transversely sealing said tube after filling with a filling material, said method comprising, in sequence, attaching the fluid withdrawing means to the lower end of the upper portion of the filler pipe before operating the machine and before the longitudinal tube reaches the lower end of the upper portion of the filler pipe, circulating a cleaning agent through said upper portion and the fluid withdrawing means, removing the withdrawing means, attaching the lower portion of the filler pipe to the lower end of the upper portion of the filler pipe, starting operation of the machine to advance the packaging material to form the longitudinal tube and the transverse seal across the longitudinal tube below the lower open end of the lower portion of the filler pipe, introducing a gaseous sterilizing agent into the upper portion of the filler pipe and directing the gaseous sterilizing agent as it flows out of the lower end of the lower portion of the filler pipe backwardly along the outside of the portions of the tiller pipe to sterilize the outside walls of the filler pipe, venting the gaseous sterilizing agent through the upper opening formed by the packaging material immediately preceding formation of the longitudinal tube, and stopping introduction of the gaseous sterilizing agent so that filler material may be introduced into the cleaned and sterilized filler pipe.
2. A device for cleaning and sterilizing a filler pipe of a packaging machine in which a continuous web of packaging material is formed into a longitudinal tube surrounding the lower open end of the filler pipe through which filler material can be supplied, said tube being subsequently sealed transversely of the tube below the lower end of the filler pipe and then separated into separate packages, said device comprising a filler pipe having a lower portion separable from an upper portion, means for controlling the separate introduction of a cleaning agent, a gaseous sterilizing agent and a filler material into said filler pipe, means detachably connectable to the lower end of the upper portion of said filler pipe when the lower portion of thefiller pipe is removed therefrom for circulating the cleaning agent through the upper portion of said filler pipe before the longitudinal tube of packaging material extends substantially beyond the lower open end of the upper portion of said filler pipe and flow reversal means mounted on the lower end of the separable lower portion of said filler pipe so that when the lower portion is connected to the upper portion of said filler pipe and is surrounded by the longidudinal tube of packaging material above the transverse seal thereof the flow of gaseous sterilizing agent therethrough will be reversed when leaving the lower open end of the lower portion of said filler pipe to flow upwardly along the outer wall of said filler pipe away from the transverse seal to sterilize said outer wall of the filler pipe, said gaseous sterilizing agent venting through the upper opening formed by the packaging material immediately preceeding formation of the longitudinal tube.
3. A device as claimed in claim 2 wherein said flow reversing means is a hemispherical body, the concave portion thereof facing upwardly, the lower end of the separable lower portion of said filler pipe extending into the concave portion of said hemispherical body and being spaced therefrom.