Method for sterilizing a container
By applying a sterilizing agent along the return path of the container receiver and combining it with UV light irradiation, the problem of incomplete sterilization in the container neck area is solved, achieving a comprehensive, efficient, and low-cost sterilization effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- KOCHS GMBH
- Filing Date
- 2024-12-17
- Publication Date
- 2026-06-16
AI Technical Summary
In existing technologies, the neck ring area is easily obstructed during the sterilization process of containers, especially PET bottles, resulting in incomplete sterilization. Furthermore, existing methods increase equipment costs and complexity.
Sterilizing agents, especially hydrogen peroxide, are applied to the return path of the container receiver and transferred to the container, including the neck ring area, through direct contact, combined with supplemental sterilization by UV light irradiation.
It achieves comprehensive and efficient sterilization of containers, especially effective sterilization of shielded areas, reducing equipment costs and complexity.
Smart Images
Figure CN122228166A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for sterilizing containers, the method employing a circulating conveying device having multiple container receivers, wherein containers are received in a receiving area by an assigned container receiver, conveyed along a conveying path by means of the container receivers, and unloaded from the assigned container receivers in an unloading area. The invention also relates to a sterilization apparatus for carrying out this method. Background Technology
[0002] The container can be sterilized while moving along the transport path.
[0003] This invention relates particularly to the beverage industry, whereby containers are designed as bottles, especially disposable PET bottles, or preforms for forming such bottles. During sterilization of the bottles or preforms, the bottles or preforms are moved by means of a circulating conveyor, such as a circulating chain or preferably a star wheel on which a container receiver is arranged.
[0004] Container receivers are typically formed by grippers or retaining recesses, so that the container is received on at least one contact surface of the container receiver.
[0005] In known sterilization methods, the sterilizing agent used to treat preforms or bottles is applied to the surface or directed or oriented onto the surface. Bottles or preforms made of PET (polyethylene terephthalate) often have a so-called neck ring on the neck, at which these containers can be handled. If the container is thus held at or in the area of the neck ring (e.g., by a gripper), the corresponding area of the surface is blocked. Therefore, there is a risk that adequate sterilization cannot be performed there (i.e., bacteria, spores, viruses, or microorganisms in general remain there or cannot be killed).
[0006] In view of this, methods and apparatus for sterilization in two stages are known in practice, in which containers are thus transported by two conveying devices and supported or gripped differently at the handover. This makes the entire container surface accessible, but leads to increased costs.
[0007] A similar method is known from EP2742958B1, in which the container receiver is designed as a gripping system. This gripping system comprises two pairs of grippers located at different heights, which switch grips during container transport along the conveyor path, thereby making all areas of the surface accessible. However, this results in considerable equipment costs, and the shape of the container and the gripping force of the grippers must be coordinated to allow for switching grips at different heights without slippage. Furthermore, depending on the type of sterilizing agent, a certain degree of obstruction can occur when the grippers are directly stacked vertically. Summary of the Invention
[0008] The objective of this invention is to provide a method for sterilizing containers and a sterilization apparatus for doing so, which can achieve reliable sterilization at the lowest possible cost.
[0009] The technical solution of the present invention and the solution to this task are the method for sterilizing containers according to claim 1 and the sterilization equipment for implementing the method according to claim 9.
[0010] Therefore, according to the present invention, based on a similar method for sterilizing containers, a sterilizing agent is applied to an empty container receiver on the return path between the unloading area and the feeding area, the sterilizing agent being at least partially transferred to the container received in the receiving area.
[0011] According to the invention, in normal production operations (which may also be referred to as transport operations with respect to containers), a sterilizing agent is continuously applied to the container receiver, more precisely, at least to the location where the container is subsequently received by the container receiver and carried during transport. The sterilizing agent initially applied to the container receiver is thus transferred to the container through direct contact. This direct contact with the container occurs precisely at the location where the container is received by the container receiver and carried, areas that are at least partially covered in conventional sterilization. The sterilizing agent can therefore also act effectively on the areas covered by the container receiver.
[0012] Within the scope of this invention, sterilization of the container receiver itself is not typically involved, but rather the transfer of the sterilizing agent to the container. It goes without saying that the sterilizing agent is thus transferred to the container while still activated and effective.
[0013] This requirement is possible for common sterilizing agents because there is usually only a relatively short path between applying the sterilizing agent to the container receiver and the subsequent receipt of the container by the container receiver.
[0014] This principle applies to various designs of the conveying device, which can be implemented as a chain or via a star wheel. In the star wheel design, a rotation angle of less than 90°, preferably less than 45°, can be set between the applied sterilizing agent and the receiving container.
[0015] In terms of efficient process control and space utilization, in the star-shaped wheel design, the conveying path between the receiving area and the unloading area preferably extends at an angle of 180° to 330°, particularly preferably 240° to 300°. The remaining portion of the circle thus constitutes a return path, on which the container receiver is unloaded and can be supplied with sterilizing agent.
[0016] Container receivers typically transfer sterilizing agent only to a small portion of the container surface, i.e., the location of direct contact. The transfer of sterilizing agent to the container along this path is generally configured within the scope of this invention to supplement the sterilization of the remaining surface.
[0017] Therefore, according to a preferred design of the invention, a primary sterilizing agent is applied to the container along the transport path on the inside and / or outside of the container. The term "primary sterilizing agent" is intended only to illustrate the sterilization of the typically significantly larger exposed surfaces on the inside and / or outside of the container. In this regard, it is clear that the same substance can be used as both sterilizing agent and primary sterilizing agent.
[0018] Hydrogen peroxide (H2O2) is particularly suitable as a sterilizing agent or primary sterilizing agent. However, other substances, such as alcohol, alkali, peracetic acid, or similar liquids with sterilizing properties, can also be considered in principle.
[0019] Regarding the sterilizing agent applied to the container receiver, it needs to be able to be transferred onto the container as a fluid, and especially a liquid.
[0020] For the sterilization of the inner side of the container and / or the remaining surfaces on the outer side of the container, in addition to using a primary sterilizing agent, sterilization can also be performed, for example, by UV light irradiation.
[0021] It is important to note that the incident UV light acts directly on the surface, and PET, as a preferred material for containers (especially in the form of bottles or preforms), is opaque in the corresponding wavelength range. Similar to when the primary sterilizing agent is applied to the inside and / or outside of the container, this can create a blocking effect on the container receiver, preventing sterilization by UV light in the blocked area. Therefore, the sterilizing agent previously applied to the container receiver according to the invention functions there.
[0022] As mentioned earlier, the container is preferably a bottle or preform with a neck ring, made of plastic, especially PET. Such a container can therefore be held in place at the neck ring in a particularly simple manner.
[0023] For containers in preform form, sterilization can be performed, in particular, before they are formed into bottles by compressed air or by filling with filler (fromfill process). Bottles can be sterilized, for example, before the filling process. In cases where hygiene requirements are particularly high, multiple sterilizations can also be performed at different stages of the process. For example, it is conceivable to first sterilize the preform in multiple steps and then subsequently sterilize the bottles thus formed.
[0024] For example, a container receiver in the form of a simple gripper can grip the container directly above or below the neck ring. Positioning the gripper below the neck ring can be particularly advantageous within the scope of this invention. The neck ring can thus be placed from above onto a gripper that typically has two gripping claws, thereby enabling reliable transfer of the sterilizing agent.
[0025] Because the container area covered by the container receiver is supplied with sterilizing agent via direct transfer within the scope of this invention, these contact areas can, if necessary, be constructed to be slightly larger, as adequate sterilization can also be ensured there. In contrast, according to prior art designs, those skilled in the art strive to minimize the covered and unsterilizable areas as much as possible.
[0026] Sterilizing agents (especially in the form of H2O2) can be supplied as gas or mist on the return path and thus condense or deposit on the container receivers they pass through. The sterilizing agent can, for example, be evaporated and discharged with air and / or water vapor from a discharge device in the form of a nozzle or similar device, so as to adhere to the container receiver as previously described. Through the condensation or deposition of the mist, the sterilizing agent is thus applied to the container receiver as a liquid.
[0027] For example, it can be specified that the vapor mixture consisting of water vapor, hydrogen peroxide vapor and air is preferably discharged continuously, wherein a vapor temperature, particularly between 110°C and 150°C, and especially about 120°C, is suitable.
[0028] In order to ensure that the sterilizing agent can be deposited or condensed on the container receiver with particular reliability, it is also possible to actively cool the container receiver before applying the sterilizing agent. For example, a cooling device can be provided that directs a cold fluid (such as cold air, liquid nitrogen, or the like) to the container receiver, especially before the application of the sterilizing agent.
[0029] However, other types of wetting can also be used in principle. Besides direct spraying, coating or brushing with sponges, brushes, or similar materials can also be considered. For example, the corresponding discharge device can be arranged on the return path so that the container receiver passes by the discharge device in direct contact.
[0030] The amount of sterilizing agent applied to the container receiver and subsequently transferred to the container depends particularly on the contact area between the container and the container receiver, and on the type of sterilizing agent. Especially for hydrogen peroxide and other sterilizing agents, according to a preferred design of the invention, the sterilizing agent is applied to the contact surface of the container receiver at a unit area dosage of 0.2 μl / cm² to 3 μl / cm² on the return path. Preferred unit area dosages are 0.3 μl / cm² to 2 μl / cm², and particularly 0.4 μl / cm² to 1 μl / cm².
[0031] The given dosage per unit area per cycle, as previously mentioned, typically involves transferring the sterilizing agent to the container receiver and from there to the container during each cycle.
[0032] The present invention also provides a sterilization apparatus for implementing the aforementioned method. The sterilization apparatus includes a circulating conveying device with multiple container receivers. The conveying device has a receiving area and a discharging area, and is configured to receive containers in the receiving area using an associated container receiver, convey the containers along a conveying path using the container receivers, and discharge the containers in the discharging area. A return path for the container receivers is provided between the discharging area and the receiving area. A sterilization device for the containers is arranged on the conveying path, and a first discharge device is provided on the return path for applying a sterilizing agent to the container receivers.
[0033] The first discharge device is configured to sterilize the covered area before it is sterilized by the sterilization apparatus. The sterilization apparatus may include at least one second discharge device and / or a UV light source.
[0034] As previously mentioned, the container receiver can be configured as a gripper, which can therefore each have a planar contact surface for planarly supporting the neck ring.
[0035] Regardless of the specific design of the container receiver, it is advantageous for the container to be directly abutted and for the transfer of sterilizing agent to be achieved there, or for the rest of the area to be substantially exposed. In this context, it is particularly suitable that the abutting surface, preferably flat, terminates at an edge or step, thereby providing a large free space there and thus good access to the inside and / or outside of the container for individual sterilization. Attached Figure Description
[0036] The invention will now be described with reference to the accompanying drawings.
[0037] The only accompanying drawing shows the sterilization equipment used to sterilize the containers. Detailed Implementation
[0038] The only accompanying drawing schematically illustrates the sterilization equipment, with a pre-formed container 1 being exemplarily conveyed to it. The sterilization equipment has a star-shaped wheel 2 that carries a plurality of container receivers 3 in the form of grippers.
[0039] As shown in the figure, during continuous operation, container 1 is received at receiving area 4 by an assigned container receiver 3, conveyed along conveying path 5 by means of the container receiver 3, and unloaded from the assigned container receiver 3 at unloading area 6.
[0040] The conveying path 5 extends over approximately three-quarters of the circumference of the star wheel 2, thus leaving a return path 7 opposite to the conveying path 5 between the unloading area 6 and the receiving area 5, on which the container receiver 3 is unloaded.
[0041] A first discharge device 8 is arranged on the return path 7, by means of which a sterilizing agent is applied to the container receiver 3. The sterilizing agent may be, for example, H2O2 evaporated and transported in gaseous form together with air and / or water vapor, so that it condenses on the surface of the container receiver 3 and forms a liquid film there.
[0042] If the container 1 is subsequently received by the container receiver 3, which is supplied with sterilizing agent, as the star wheel 3 rotates, the sterilizing agent is regionally transferred to the container 1 through direct contact, i.e., transferred to the position where the container 1 is held by the container receiver 3.
[0043] In the illustrated embodiment, container 1 has a neck ring 9 at which it is carried. The sterilizing agent is thus transferred, in particular, to the neck ring 9.
[0044] A sterilization device with a second discharge device 10 is also provided along the conveying path 5, by means of which the main sterilizing agent is applied to the inside and outside of the container. The distinction between the terms "sterilizing agent" and "main sterilizing agent" is particularly relevant to sterilizing different areas of the container 1, where the same substance, such as H2O2, can be used.
[0045] However, in principle, the sterilization device installed on the transport path 5 can also work using other substances or UV light.
[0046] Regarding the first discharge device 8, designing it as a nozzle is particularly suitable. However, liquid sterilizing agents can also be applied through sponges, brushes, or similar means in direct contact.
[0047] Within the scope of this invention, particularly efficient sterilization of the entire container 1 can be achieved because reliable sterilization can be achieved even in areas covered by the container receiver 3 through the transfer of sterilizing agent.
[0048] List of reference numerals
[0049] 1 container
[0050] 2 star wheels
[0051] 3-Container Receiver
[0052] 4 receiving area
[0053] 5 Conveying Path
[0054] 6 Unloading Area
[0055] 7 Return Path
[0056] 8 First discharge device
[0057] 9 neck rings
[0058] 10 Second Discharge Device
Claims
1. A method for sterilizing containers (1), said method using a circulating conveying device having a plurality of container receivers (3), wherein, The container (1) is received at the receiving area (4) by an associated container receiver (3), conveyed along the conveying path (5) by means of the container receiver (3), and unloaded from the associated container receiver (3) at the unloading area (6), characterized in that a sterilizing agent is applied to the unloaded container receiver (3) on the return path (7) between the unloading area (6) and the feeding area (4), wherein the sterilizing agent is at least partially transferred to the container (1) received in the receiving area (4).
2. The method according to claim 1, characterized in that, The container (1) is treated with a primary sterilizing agent along the transport path (5) on the inside and / or outside of the container.
3. The method according to claim 2, characterized in that, The same substance is used as both a sterilizing agent and a primary sterilizing agent.
4. The method according to any one of the preceding claims, characterized in that, Hydrogen peroxide is used as a sterilizing agent.
5. The method according to any one of the preceding claims, characterized in that, The container (1) is held in the area of the neck ring (9) during its transport in the form of a bottle or preform made of plastic.
6. The method according to any one of the preceding claims, characterized in that, The sterilizing agent is provided as a gas or mist on the return path (7) and condenses or deposits on the container receiver (3).
7. The method according to any one of the preceding claims, characterized in that, The sterilizing agent, as a vapor mixture of water vapor, hydrogen peroxide vapor and air, is preferably continuously discharged at a vapor temperature between 110°C and 150°C, especially about 120°C.
8. The method according to any one of the preceding claims, characterized in that, The sterilizing agent is applied as a liquid to the container receiver (3).
9. The method according to claim 8, characterized in that, The sterilizing agent is applied to the contact surface of the container receiver (3) at a unit area dosage of 0.2 µl / cm² to 3 µl / cm² on the return path (7).
10. The method according to any one of the preceding claims, characterized in that, The container receiver (3) is cooled before the sterilizing agent is applied.
11. A sterilization apparatus for carrying out the method according to any one of the preceding claims, the sterilization apparatus comprising a circulating conveying device having a plurality of container receivers (3), the conveying device having a receiving area (4) and a discharging area (6), and the conveying device being configured to receive a container (1) at the receiving area (4) by means of an associated container receiver (3), to convey the container along a conveying path (5) by means of the container receiver (3), and to discharge the container at the discharging area (6), wherein, A return path (7) for the container receiver (3) is provided between the unloading area (6) and the receiving area (4), a sterilization device for the container (1) is provided on the conveying path (5), and a first discharge device (8) is provided on the return path (7) for applying sterilizing agent to the container receiver (3).
12. The sterilization equipment according to claim 11, wherein, The container receiver (3) is constructed as a gripper.
13. The sterilization equipment according to claim 12, wherein, The grippers each have a planar contact surface for planarly supporting the neck ring (9).
14. The sterilization equipment according to any one of claims 11 to 13, wherein, The conveying device includes a star wheel (2), which carries a container receiver (3).