Abstract:
An apparatus for sterilizing cap-like container closures includes a transport system for moving closures through treatment zones. The first zone preheats the closures, the second exposes them to a sterilizing agent, and the third activates or dries them. The first and third zones each have a rotor that circulates about a rotor axis thereof, and closure holders formed on a periphery thereof for moving closures through the first zone from a closure pickup disposed therein to a first closure delivery position, and through the third zone from a second closure delivery position disposed therein to a closure discharge. The second treatment zone is between the first and second closure delivery positions such that closures delivered to the first position, after passing the second zone and after exposure to the sterilizing agent, are passed on to a closure holder ready at the second position of the rotor in the third zone.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is the national phase under 35 USC 371 of international application no. PCT/EP2011/001465, filed Mar. 24, 2011, which claims the benefit of the priority date of German application no. 10 2010 025 541.6, filed Jun. 29, 2010. The contents of the aforementioned applications are incorporated herein in their entirety. 
     FIELD OF DISCLOSURE 
     The invention relates to a device for sterilizing closures. 
     BACKGROUND 
     It is conventional and well-known, for example in plants in the drinks industry, to sterilize the closures used to close filled bottles or other containers, in particular cap-like closures such as screw closures, flat caps, crown corks etc., before use, i.e. before application to the container concerned, inter alia using sterilizing agents that consist of H 2 O 2  vapor (vaporized aqueous hydrogen peroxide solution with sufficiently high concentration of H 2 O 2 ) or a gaseous and/or vaporous carrier medium enriched with H 2 O 2  vapor. To achieve an effective sterilization with high disinfection rate, before exposure to the sterilizing agent the closures are preheated for example to a temperature in the range between 50° C. and 85° C., and then after treatment or exposure to the gaseous and/or vaporous sterilizing agent, dried using a preferably heated sterile gaseous and/or vaporous medium, for example using preferably heated sterile air, so that the sterilized closures can then be used for closing containers or supplied to a closing machine for this. 
     SUMMARY 
     The object of the invention is to produce a device that allows a high performance (number of sterilized closures per time unit) with a high quality of sterilization or disinfection rate. 
     Particular advantages of the device according to the invention are, among others, that despite its high performance, the device can be produced very compactly with little construction space or volume, and that constant or reproducibly high disinfection rates are achieved on sterilization. The device according to the invention is suitable for closures of widely varying types, in particular also for cap-like closures such as screw closures, flat caps, crown corks etc. 
     Preferably, in the device according to the invention, the treatment zones there can be subjected to a slight positive pressure of a sterile gaseous and/or vaporous medium so that the penetration of ambient air and the germs carried with this into the treatment zones is effectively avoided, in particular also in the region of closure inlets and outlets. 
     Refinements, advantages and possible applications of the invention arise from the description below of embodiment examples and from the figures. All the features described and/or shown in the figures alone or in any combination are in principle the subject of the invention irrespective of their summary in the claims or back reference. The content of the claims is also made a constituent part of the description. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The invention is described in more detail below with reference to the figures and one embodiment example in which: 
         FIG. 1  shows, in perspective depiction and in various views, a device according to the invention for sterilizing closures intended for closing bottles or similar containers; 
         FIGS. 2 and 3  show, in enlarged perspective view, sections of the depiction in  FIG. 1 ; 
         FIG. 4  is a simplified depiction of a vertical section of the device in  FIG. 1 ; 
         FIG. 5  is a simplified depiction of a horizontal section through an upper treatment zone serving as a pre-heating zone of the device in  FIG. 1 ; and 
         FIG. 6  is a simplified partial depiction and side view, of two of the closure holders formed on a rotor of the device. 
     
    
    
     DETAILED DESCRIPTION 
     The device designated generally in the figures as  1  serves to sterilize closures  2 , for example closures in the form of caps, screw caps, flat caps or crown corks etc., that are used to close containers not shown, e.g. in the form of bottles. The device  1  for this preferably forms an assembly that is connected before a closing machine for closing the containers and from which the sterilized closures  2  are supplied to the closing machine under sterile or germfree conditions. 
     The device  1  comprises, among other things, a device housing  3  that, in top view, has a polygonal shape enclosing a vertical machine axis MA. In the embodiment shown, the housing is hexagonal. The interior of the housing  3 , with the exception of inlets and outlets for the closures  2 , is tightly sealed against the environment. 
     In the embodiment shown, the housing  3  comprises three successive housing segments in the axial direction of the machine axis MA, namely: an upper housing segment  3 . 1 , which substantially comprises the upper hexagonal housing wall  5  fitted with an inspection cover  4 , a peripheral wall  6 , which is fitted with large format inspection windows  7  each tightly closed by glazing, and an intermediate floor  8 , an adjacent housing segment  3 . 2  with a closed peripheral wall  9 , and an adjacent housing segment  3 . 3 , which substantially comprises the lower hexagonal housing wall  10  and peripheral wall  6  with the large format inspection windows  7  tightly closed by glazing. 
     This gives a modular structure, which is simple to manufacture, of at least the housing  3 . 
     The intermediate floor  8  divides the interior of the housing  3  into an upper treatment zone  11 , formed in housing segment  3 . 1  and a lower treatment zone  12 , separate from treatment zone  11  and formed in housing segments  3 . 2  and  3 . 3 . In both treatment zones  11  and  12 , a rotor  13  is provided that can be driven to circulate about the common vertical machine axis MA. In the embodiment shown, the two rotors  13 , which are each part of a transport system for the closures  2 , are designed to be identical, each as a circular cylindrical hollow drum with a drum casing with a cage-like structure that is formed by a multiplicity of closure holders  14 , each receiving a multiplicity of closures  2 . The closure holders  14 , which are oriented with their longitudinal extension to be parallel or substantially parallel to machine axis MA are, at their upper end, open for introduction of closures  2  and are, at their lower end, open for discharge of closures  2 . The closures, as a whole, form the cage-like structure or casing of the respective rotor  13  and are here arranged distributed on the periphery of rotor  13  at constant angle or pitch intervals about the machine axis MA. Ring-like brackets  15  concentrically surrounding the machine axis MA and offset to each other in the direction of this axis connect the closure holders  14  together and to the grid-like structure of the respective rotor  13 . In the region of their lower ends, the closure holders  14  of each rotor  13  are attached to a circular disc-shaped carrier element  16  arranged coaxial with machine axis MA such that the closure holders  14  each protrude beyond the peripheral surface of the carrier element  16 . 
     The closure holders  14  are also formed into a grid. Each consists of several rod or bar-like closure guide rails spaced from each other and oriented parallel to machine axis MA. The guide rails for between them a receiving chamber to receive a multiplicity of closures  2  such that the closures  2  in each closure holder  14  form a single row extending in an axial direction parallel to machine axis MA and exposed as far as possible in the closure holders  14 , i.e. each is covered only on a small part of its surface by the closure guide rails  14 . Furthermore the closure holders  14  in the embodiment shown are designed such that the closures  2  in the closure holders  14  have a pre-specified orientation in relation to the machine axis MA, such that they are oriented with their closure or cap axis radial to the machine axis MA and, for example, with their open cap side radially outwards. 
     With the carrier element  16  or with a shaft  17  connected with the carrier element  16  and arranged coaxial with machine axis MA, the upper rotor  13  in the treatment zone  11  is mounted in a bearing  18  of the intermediate floor  8  and the lower rotor  13  in the treatment zone  12  is mounted on a bearing  19  provided on the lower housing wall  10 , both of which are rotatable about machine axis MA. An independent drive with gears and an independent drive motor (electric motor) is allocated to each rotor  13 , namely drive  20  to the upper rotor  13  and drive  21  to the lower rotor  13 . 
     In the upper region of treatment zone  11 , above the movement track of the closure holders  14 , there is provided a closure pickup  22  to which the closures  2  to be sterilized are supplied via a delivery section  23  in which the closures  2  already have the orientation corresponding to their orientation in the closure holders  14 . In the region of the underside of housing  3 , below the movement track of the closure holders  14 , there is a closure discharge that is substantially formed by the inlet or open end of a delivery section  24  that extends with this end through the lower housing wall  10  into the lower treatment zone  12  and with its open end is arranged below the movement track of the closure holders  14  of the lower rotor  13 . Above the delivery track  24 , the sterilized closures  2  are supplied germ-free to the closing machine, which is not shown. 
     In addition to the closure discharge formed by the delivery section  24 , two additional closure discharges are provided, which are each formed by a closure guide  25  and  26 , for empty running of the device  1  and/or rotors  13  i.e. for removal of closures  2  from the device  1  and/or from the rotors  13  or their closure holders  14 , for example in the event of fault in a plant containing the device  1 , on a format change i.e. on changeover from one closure type to another closure type etc. The closure guides  25  and  26  guided out of the housing  3  each terminate in the treatment zones  11  and  12  respectively below the movement track of the closure holders  14 . By corresponding control means not shown, the inlets there of the closure guides  25  and  26  can be controlled such that closures  2  do not reach the closure guides  24  and  26  in normal operation of the device  1  but only on empty running of the device  1  and/or rotors  13 . 
     In the embodiment shown, the delivery sections  23  and  24  and the closure guides  25  and  26  are each formed by several guide rails receiving and guiding the closures between them. Furthermore, in the embodiment shown, at least the delivery sections  23  and  24 , at least in the vicinity of the device  1 , each have a vertical course so that the closures  2  in these delivery sections, as in the closure holders  14 , are moved or conveyed purely by gravity. In order to avoid recontamination of the sterilized closures  2  on delivery section  24 , this is held in a sheath or housing, which is not shown, that is preferably exposed to a positive pressure of a sterile gaseous and/or vaporous medium, for example with pressurized sterile air. 
     In the inside of housing  3 , between the underside of the upper rotor  13  and the top of the lower rotor  13 , there is formed a treatment section or zone  27  comprising a grid-like closure guide  28  that extends parallel to machine axis MA and is designed to receive a multiplicity of closures  2  in a single row, and in which the closures  2  are oriented in the same manner in relation to machine axis MA as in the closure holders  14 . The closure guide  28  passing through the intermediate floor  8  is arranged with its upper open end at a closure delivery position  29  below the movement track of the closure holders  14  of the upper rotor  13  and with its lower open end at a closure delivery position  30  above the movement track of the closure holders  14  of the lower rotor  13 . The closure guide  28 , at least over the majority of its length, is held in a chamber  31  that is located below the intermediate floor  8  in the treatment zone  12  and in which the closures  2  are treated with or exposed to the hot sterilizing agent that is formed by H 2 O 2  vapor or contains H 2 O 2  vapor in a gaseous and/or vaporous carrier medium and is introduced into chamber  31  via an inlet  32 . 
     The upper treatment zone  11  serves to preheat the closures  2  to a desired or preselected preheat temperature, for example in the range between 50° C. and 85° C. For this, within the rotor  13  there is provided a heater  33  with a circulating or blown air fan  34  that has a multiplicity of blade-like guide vanes or impellers  35  and that is driven such that within the treatment zone  11  there is a flow of hot gaseous and/or vaporous medium, for example a hot air flow, with a flow direction from the circulating air fan  34  through the rotor  34  or through the closure holders  14  radially towards the outside (mainly in the lower region of treatment zone  11 ) and then again at least partly through the rotor  13  or through the closure holders  14  back in the direction of the rotor center (mainly in the upper region of the treatment zone  11 ). 
     The lower treatment zone  12  serves substantially to dry the closures  2  with a sterile, preferably heated, gaseous and/or vaporous medium, for example with preferably heated sterile air. The gaseous and/or vaporous medium is supplied via an inlet  36  and extracted via an outlet  37 . The design is such that there can be no direct flow between the inlet  36  and outlet  37 , and that, via openings in the intermediate floor  8 , a flow of sterile medium is established from the treatment zone  12  into the treatment zone  11 , and, at the passages at least of the delivery section  23  and the closure guides  25  and  26 , a flow of sterile medium is established towards the outside in order to prevent the penetration of ambient air into the interior of the housing  3 . 
     The closure pickup  22  and the delivery position  29  are arranged at an angular distance that corresponds to a multiple of the pitch interval of the closure holders  14  on the upper rotor  13  such that whenever a closure holder  14  of the upper rotor  13  with its upper open end has reached the closure delivery point  22 , another closure holder  14  of this rotor with its lower open end is at the delivery position  29 . In the same way the lower delivery position  30  and the closure discharge formed by delivery section  24  are spaced at an angular interval that corresponds to a multiple of the pitch spacing of the closure holders  14  on the lower rotor  13  such that whenever a closure holder  14  of the lower rotor  13  with its upper open end has reached the delivery position  30 , another closure holder  14  of this rotor with its open end is at the closure discharge. 
     In relation to the direction of rotation of the rotor  13  concerned, the closure pickup  22  and the closure delivery position  29  and the closure delivery position  30  and the closure discharge formed by the delivery section  24  are spaced from each other by as large an angular region as possible, for example by an angular region of at least 330°. 
     At least during normal operation, the two rotors  13  are driven by their drives  20  and  21  in the same direction and in synchrony such that, in particular when a closure holder  14  of the upper rotor  13  is at the delivery position  29 , an empty closure holder  14  of the lower rotor is ready at the delivery position  30 . 
     At the closure pickup  22 , in each stoppage phase of the cycled rotary movement of the upper rotor  13 , a closure holder  14  of this rotor is filled, for example, completely with closures  2  that are provided in delivery section  23  as a sufficiently large stock of closures. With the circulating upper rotor  13 , the closures  2  held in the respective closure holder  14  are then moved from the closure pickup  22 , through the treatment zone  11 , to the closure delivery position  29  and there heated by the hot flow generated by the heater  33  and the circulating air fan  34 . 
     As shown in  FIG. 6 , on the rotary movement of rotor  13  indicated with arrow A, the lowest closure  2  of each closure holder  14  that is arranged in a closure holder  14 , rolls with its peripheral surface in the manner of a friction wheel on a closure contact surface  8 . 1  formed by the intermediate floor  8  and not carried with rotor  13 , whereby according to arrow B a rotary or rolling movement is generated for the lowest closure  2  and is transmitted from closure to closure to all closures  2  arranged in the respective closure holder  14  and lying against each other with their peripheral surfaces so that all closures  2  in each closure holder  14  rotate in opposite directions according to arrow B and are thus exposed to the hot air flow over their entire surface. 
     Whenever a closure holder  14  of the upper rotor  13  has reached the closure delivery position  29 , all closures  2  of that holder fall through the treatment zone  27  or through the closure guide  28  there into a ready, empty closure holder  14  of the lower rotor  13 . In the treatment zone  27 , the closures  2  are exposed to the hot sterilizing agent, which is constantly supplied via a connection  32 . 
     The closures  2  held in the respective closure holder  14  of the lower rotor  13  are moved with this rotor  13  through the treatment zone  12  and there dried by the flow sterile gaseous and/or vaporous medium. According to  FIG. 6 , again on the rotary movement (arrow A) of the lower rotor  13 , the lowest closure in each closure holder  14  rolls with its peripheral surface in the manner of a friction wheel on a closure contact surface  10 . 1  formed by the housing wall  10  and not carried with the rotor  13 , generating a rotary or rolling movement (arrow B) which is transferred from closure to closure to all closures  2  arranged in the respective closure holder  14  and lying against each other with their peripheral surfaces so that these rotate in opposite directions (arrow B) and are thus dried optimally on all surface regions. At the closure discharge then all closures fall from the respective closure holder into the delivery section  24  for further delivery to the closing machine. 
     The separate drives  20  and  21  allow various operating modes of the device  1 . Thus for example it is possible at the start of operation to fill the closure holders  14  of the upper rotor completely with closures  2  and then drive the lower rotor  13  via its drive  21  initially in cycles when a closure row is introduced from the upper rotor  13  into the closure holder  14  of the lower rotor  13 . Conversely before the end of operation it is also possible to switch off the upper rotor  13  and run the lower rotor empty with delivery of all closures to the delivery section  24 . Furthermore the separate drives  20   21  create the possibility, for example on fault and/or on a format change, of running the rotors  13  empty individually, i.e. delivering the closures for example also via the closure guides  25  and  26 . 
     The invention has been described above with reference to one embodiment example. Evidently numerous modifications and derivations are possible without leaving the inventive concept fundamental to the invention. 
     It has been assumed above that the movement of the closures  2  within the delivery sections  23  and  24 , closure guides  24  and  26 , the closure guide and closure holders  14 , takes place by gravity. In principle it is also possible to provide, at these elements, transport nozzles for the emergence of a sterile gaseous and/or vaporous transport medium, for example for the emergence of sterile transport air. 
     Furthermore, at the treatment zones  11  and  12  and at the treatment section  27 , preferably means not shown are provided for cleaning, and/or measurement sensors not shown are provided for measurement and/or monitoring of the state of the treatment zones. 
     Furthermore, the treatment zone  27  can also comprise at least two preferably parallel closure guides  28 , which are then arranged so that in each stoppage phase of the cycled rotary motion of the rotors  13 , each closure guide  28 , with its inlet or with its upper end, lies opposite the outlet or the lower open end of a closure holder  14  of the upper rotor  13 , and with its outlet or its lower end opposite the inlet or open upper end of an empty closure holder  14  of the lower rotor  13 . The closure pickup  22  and the closure discharge formed by the delivery section  24  are then designed for simultaneous filling and evacuation of several closure holders  14 . 
     Furthermore the respective closure contact surfaces  8 . 1  and/or closure contact surface  10 . 1  can also be formed such that they are moved relative to rotor  13  or circulate about the machine axis MA so as to achieve the above-mentioned rolling movement of the lowest closures  2  respectively and hence the opposite movement of the closures  2  in the closure holders  14 . 
     LIST OF REFERENCE NUMERALS 
     
         
           1  Device 
           2  Closure 
           3  Housing 
           3 . 1 - 3 . 3  Housing segment 
           4  Inspection cover 
           5  Upper housing wall 
           6  Housing wall 
           7  Inspection window 
           8  Intermediate floor 
           8 . 1  Closure contact surface 
           9  Housing wall 
           10  Lower housing wall 
           10 . 1  Closure contact surface 
           11 , 12  Treatment zone 
           13  Rotor 
           14  Closure holder 
           15  Bracket 
           16  Carrier element 
           17  Shaft 
           18 ,  19  Bearing 
           20 ,  21  Drive 
           22  Closure pickup 
           23 ,  24  Delivery section 
           25 ,  26  Closure guide 
           27  Treatment section 
           28  Closure guide 
           29 ,  30  Delivery position 
           31  Chamber of treatment section  27   
           32  Inlet for sterilizing agent 
           33  Heater 
           34  Circulating air fan 
           35  Air guide plate 
           36  Sterile air inlet 
           37  Sterile air outlet 
         A Rotary movement of rotor  13   
         B Rolling or rotary movement of closures  2   
         MA Vertical machine axis