Patent Publication Number: US-11655133-B2

Title: Cap sterilizer, content filling system, cap sterilization method, and content filling method

Description:
This application is a divisional application of U.S. patent application Ser. No. 16/306,527, filed Nov. 30, 2018, which is a National Stage of International Application No. PCT/JP2017/020279, filed May 31, 2017, which claims priority to Japanese Patent Applications No. 2017-018936, filed Feb. 3, 2017, No. 2016-148789, filed Jul. 28, 2016, No. 2016-148802, filed Jul. 28, 2016, No. 2016-109230, file May 31, 2016, No. 2016-148817, Jul. 28, 2016, No. 2016-120994, filed Jun. 17, 2016, No. 2016-121000, filed Jun. 17, 2016, and No. 2016-148813, filed Jul. 28, 2016. The disclosures of the prior applications are hereby incorporated by reference herein in their entireties. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a cap sterilizer, a content filling system, a cap sterilization method and a content filling method. 
     BACKGROUND ART 
     A sterile filling system (aseptic filling system) has been known in which a sterilized content is filled inside a sterilized container (PET bottle) in a sterile environment and then the container is capped with a cap. Specifically, in the sterile filling system, a molded container is fed to the sterile filling system, and a hydrogen peroxide aqueous solution as a sterilant is sprayed on the container in the sterile filling system. After that, the container is dried and sterilized, and then, a content is aseptically filled inside the container. As another method, there is a method of adding dropwise a small amount of sterilant on an inner surface of a container at the time of molding the container, sealing a mouth to sterilize the inner surface of the container with vapor of the vaporized sterilant (hydrogen peroxide), feeding the sterilized container to a sterile filling system, sterilizing an outer surface of the container in the sterile filling system, and then opening the mouth to aseptically fill the content. 
     In such a sterile filling system, when a content is filled in a container, and seaming is performed with a cap to produce a product, it is necessary to sterilize the cap as well as the container. As such a cap sterilizer for sterilizing a cap, those described in Patent Literatures 1 to 3 are known, for example. 
     However, in the conventional cap sterilizers, there is a problem that it is difficult to increase the conveying speed of a cap. If the conveying speed of the cap is increased in the conventional cap sterilizers, the sterilization effect on an outer surface of the cap may be deteriorated. In addition, if the conveying speed of the cap is to be increased, there are problems that the cap sterilizer becomes large, the cost of capital investment increases, and the cost of medicine, thermal energy or washing water required for sterilization increases. Furthermore, in recent years, various caps such as a light-weight cap and a cap for carbonated drinks have been used in a sterile filling system, and in addition to sterilization in a short time, controlling a cap seaming angle and a torque within a specified range is required, for example. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: JP 6-293319 A 
     Patent Literature 2: JP 2011-11811 A 
     Patent Literature 3: JP 2012-500759 A 
     The present invention has been made in view of these circumstances, and an object of the present invention is to provide a cap sterilizer capable of reliably sterilizing a cap even when the conveying speed of the cap increases, a content filling system, a cap sterilization method, and a content filling method. Another object of the present invention is to provide a cap sterilizer capable of increasing the conveying speed of a cap, a content filling system, a cap sterilization method, and a content filling method. 
     SUMMARY OF INVENTION 
     The present invention is a cap sterilizer, and the cap sterilizer includes an infeed chamber, a sterilant atomizing chamber which sprays a sterilant against a cap fed from the infeed chamber, and an air rinse chamber which air-rinses the cap sprayed with the sterilant in the sterilant atomizing chamber. In this cap sterilizer, the infeed chamber, the sterilant atomizing chamber, and the air rinse chamber are arranged in this order along a conveying direction of the cap, at least the infeed chamber and the air rinse chamber are exhausted, and an exhaust pressure in the infeed chamber and an exhaust pressure in the air rinse chamber are higher than an exhaust pressure in the sterilant atomizing chamber, or the sterilant atomizing chamber is not exhausted. 
     In the cap sterilizer of the present invention, the exhaust pressure in the air rinse chamber is higher than the exhaust pressure in the infeed chamber. 
     The present invention is a cap sterilizer further including a washing chamber which washes the cap air-rinsed in the air rinse chamber, and in the cap sterilizer, the exhaust pressure in the washing chamber is higher than the exhaust pressure in the infeed chamber. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilization method, and the cap sterilization method includes a step of feeding a cap from an infeed chamber to a sterilant atomizing chamber, a step of spraying a sterilant against the cap in the sterilant atomizing chamber, and a step of air-rinsing the cap, sprayed with the sterilant in the sterilant atomizing chamber, in an air rinse chamber. In this cap sterilization method, the infeed chamber, the sterilant atomizing chamber, and the air rinse chamber are arranged in this order along a conveying direction of the cap, at least the infeed chamber and the air rinse chamber are exhausted, and an exhaust pressure in the infeed chamber and an exhaust pressure in the air rinse chamber are higher than an exhaust pressure in the sterilant atomizing chamber, or the sterilant atomizing chamber is not exhausted. 
     The present invention is a cap sterilizer, and the cap sterilizer includes a first infeed chamber into which a cap is introduced, a second infeed chamber into which hot air is sent, and a sterilant atomizing chamber which sprays a sterilant against the cap fed from the second infeed chamber. In this cap sterilizer, the first infeed chamber, the second infeed chamber, and the sterilant atomizing chamber are arranged in this order along a conveying direction of the cap, and the first infeed chamber and the second infeed chamber are separated from each other by a partition wall. 
     The present invention is a cap sterilizer further including an air rinse chamber which air-rinses the cap sprayed with the sterilant in the sterilant atomizing chamber. 
     In the cap sterilizer of the present invention, an internal pressure of the first infeed chamber is maintained at −100 Pa or more and 10 Pa or less. 
     In the cap sterilizer of the present invention, an internal pressure of the second infeed chamber is maintained at 50 Pa or more and 200 Pa or less. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilizer, and the cap sterilizer includes an infeed chamber and a sterilant atomizing chamber which sprays a sterilant against a cap fed from the infeed chamber. In this cap sterilizer, the sterilant atomizing chamber includes a spray nozzle which sprays the sterilant and a cover which covers surroundings of the spray nozzle. 
     In the cap sterilizer of the present invention, the sterilant atomizing chamber includes a rotation conveyance mechanism which conveys the cap while rotating, and the cover has a fan or arc-shape as viewed from the front side. 
     In the cap sterilizer of the present invention, the spray nozzle includes a spray nozzle for outer surface which supplies the sterilant to an outer surface side of the cap and a spray nozzle for inner surface which supplies the sterilant to an inner surface side of the cap, and the spray nozzle for outer surface is located downstream of the spray nozzle for inner surface in the conveying direction of the cap. 
     In the cap sterilizer of the present invention, a washing nozzle which ejects a washing liquid toward an interior of the cover is provided inside the cover. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilizer, and the cap sterilizer includes a spray nozzle which sprays a sterilant against a cap and an air rinse nozzle which air-rinses the cap sprayed with the sterilant by the spray nozzle. In this cap sterilizer, sterile hot air is blown against both inner and outer surfaces of the cap by the air rinse nozzle. 
     In the cap sterilizer of the present invention, as the sterile hot air is blown by the air rinse nozzle, temperature of the cap rises to 40° C. or more. 
     The present invention is a cap sterilizer further including a washing nozzle which washes the cap air-rinsed by the air rinse nozzle. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilization method, and the cap sterilization method includes a step of spraying a sterilant against a cap and a step of air-rinsing the cap sprayed with the sterilant. In this cap sterilization method, sterile hot air is blown against both inner and outer surfaces of the cap in the air-rinsing step. 
     The present invention is a cap sterilizer, and the cap sterilizer includes a spray nozzle which sprays a sterilant against a cap, an air-rinse nozzle which air-rinses the cap sprayed with the sterilant by the spray nozzle, and a washing nozzle which washes the cap air-rinsed by the air rinse nozzle. In this cap sterilizer, the spray nozzle, the air rinse nozzle, and the washing nozzle are arranged in this order along a conveying direction of the cap, and a washing liquid is blown against the cap by the washing nozzle to wash the cap. 
     The present invention is a cap sterilizer further including an air blow nozzle which blows air against the cap to remove the washing liquid adhering to the cap. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilization method, and the cap sterilization method includes a step of spraying a sterilant against a cap, a step of air-rinsing the cap sprayed with the sterilant, and a step of washing the air-rinsed cap. In this cap sterilization method, in the washing step, a washing liquid is blown against the cap to wash the cap. 
     The present invention is a cap sterilization method further including a step of blowing air against the cap to remove the washing liquid adhering to the cap. 
     In the cap sterilization method of the present invention, when air is blown against the cap, a part of the washing liquid adhering to the cap is left. 
     The present invention is a cap sterilizer, and the cap sterilizer includes a sterilant atomizing chamber which sprays a sterilant against a cap and an air rinse chamber which air-rinses the cap sprayed with the sterilant in the sterilant atomizing chamber. In this cap sterilizer, sterile hot air is blown against both inner and outer surfaces of the cap in the air rinse chamber. 
     In the cap sterilizer of the present invention, as the sterile hot air is blown in the air rinse chamber, temperature of the cap rises to 40° C. or more. 
     The present invention is a cap sterilizer further including a washing chamber which washes the cap air-rinsed in the air rinse chamber. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilization method, and the cap sterilization method includes a step of feeding a cap to a sterilant atomizing chamber, a step of spraying a sterilant against the cap in the sterilant atomizing chamber, and a step of air-rinsing the cap, sprayed with the sterilant in the sterilant atomizing chamber, in an air rinse chamber. In this cap sterilization method, sterile hot air is blown against both inner and outer surfaces of the cap in the air rinse chamber. 
     The present invention is a cap sterilizer, and the cap sterilizer includes a sterilant atomizing chamber which sprays a sterilant against a cap, an air rinse chamber which air-rinses the cap sprayed with the sterilant in the sterilant atomizing chamber, and a washing chamber which washes the cap air-rinsed in the air rinse chamber. In this cap sterilizer, the sterilant atomizing chamber, the air rinse chamber, and the washing chamber are arranged in this order along a conveying direction of the cap, and in the washing chamber, a washing liquid is blown against the cap to wash the cap. 
     In the cap sterilizer of the present invention, air is blown against the cap in the washing chamber to remove the washing liquid adhering to the cap. 
     In the cap sterilizer of the present invention, a conveying speed of the cap is 100 cpm or more and 1500 cpm or less. 
     The present invention is a content filling system including the cap sterilizer. 
     The present invention is a cap sterilization method, and the cap sterilization method includes a step of spraying a sterilant against a cap in a sterilant atomizing chamber, a step of air-rinsing the cap, sprayed with the sterilant in the sterilant atomizing chamber, in an air rinse chamber, and a step of washing the cap, air-rinsed in the air rinse chamber, in a washing chamber. In this cap sterilization method, the sterilant atomizing chamber, the air rinse chamber, and the washing chamber are arranged in this order along a conveying direction of the cap, and in the washing chamber, a washing liquid is blown against the cap to wash the cap. 
     In the cap sterilization method of the present invention, air is blown against the cap in the washing chamber to remove the washing liquid adhering to the cap. 
     In the cap sterilization method of the present invention, when air is blown against the cap, a part of the washing liquid adhering to the cap is left. 
     The present invention is a cap sterilizer, and the cap sterilizer includes a sterilant atomizing wheel, which conveys a cap while rotating and sprays a sterilant against the cap being conveyed, and an air rinse wheel which conveys the cap, sprayed with the sterilant in the sterilant atomizing wheel, while rotating and air-rinses the cap being conveyed. 
     In the cap sterilizer of the present invention, the sterilant atomizing wheel has a rotating mechanism which conveys the cap while rotating and a spray nozzle which blows a sterilant against the cap rotated and conveyed by the rotating mechanism. 
     In the cap sterilizer of the present invention, the sterilant atomizing wheel further has a supply spray which supplies a sterilant and a heater which heats the sterilant from the supply spray, and the sterilant heated by the heater is supplied to the spray nozzle. 
     The present invention is a content filling system, and the content filling system includes a bottle sterilizer which sterilizes a bottle, a filling device which fills a content into the bottle, the cap sterilizer, and a cap attachment device which attaches the cap, delivered from the cap sterilizer, to a mouth of the bottle filled with the content by the filling device. 
     In the content filling system of the present invention, both the cap sterilizer and the cap attachment device are disposed in a sterile chamber. 
     In the content filling system of the present invention, the bottle sterilizer, the filling device, the cap sterilizer, and the cap attachment device are connected to each other by a wheel and disposed in a sterile chamber. 
     The present invention is a cap sterilization method, and the cap sterilization method includes a sterilant spray step of conveying a cap while rotating the cap by a sterilant atomizing wheel and spraying a sterilant against the cap being conveyed and an air-rinsing step of conveying the cap, sprayed with the sterilant, while rotating the cap by the air rinse wheel and air-rinsing the cap being conveyed. 
     The present invention is a content filling method, and the content filling method includes a bottle sterilization step of sterilizing a bottle by a bottle sterilizer, a filling step of filling the bottle with a content by a filling device, a sterilant spray step of conveying a cap while rotating the cap by a sterilant atomizing wheel of a cap sterilizer and spraying a sterilant against the cap being conveyed, an air-rinsing step of conveying the cap, sprayed with the sterilant, while rotating the cap by an air rinse wheel of the cap sterilizer and air-rinsing the cap being conveyed, and a cap attachment step of attaching the sterilized cap to a mouth of the bottle by a cap attachment device. 
     In the content filling method of the present invention, the bottle sterilizer, the filling device, the cap sterilizer, and the cap attachment device are connected to each other by a wheel and disposed in a sterile chamber. 
     According to the present invention, even when the conveying speed of the cap increases, the cap can be reliably sterilized. 
     According to the present invention, it is possible to increase the conveying speed of the cap. Since the cap sterilizer is disposed in the sterile chamber, there is no need to provide a dedicated sterile chamber for cap sterilization. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic plan view illustrating a content filling system according to a first embodiment of the present invention. 
         FIG.  2    is a schematic front view illustrating a cap sterilizer according to the first embodiment of the present invention. 
         FIG.  3    is a schematic cross-sectional view (cross-sectional view taken along the line III-III in  FIG.  2   ) illustrating a sterilant atomizing chamber of the cap sterilizer according to the first embodiment of the present invention. 
         FIG.  4    is a schematic cross-sectional view illustrating a modification of the sterilant atomizing chamber. 
         FIG.  5    is a schematic front view illustrating a modification of the sterilant atomizing chamber. 
         FIG.  6    is a partial schematic cross-sectional view illustrating an air rinse chamber. 
         FIG.  7    is a schematic front view illustrating a cap sterilizer according to a second embodiment of the present invention. 
         FIG.  8    is a schematic front view illustrating a cap sterilizer according to a third embodiment of the present invention. 
         FIG.  9    is a schematic front view illustrating a cap sterilizer according to a modification of the third embodiment of the present invention. 
         FIG.  10    is a schematic front view illustrating a cap sterilizer according to a fourth embodiment of the present invention. 
         FIG.  11    is a schematic front view illustrating a cap sterilizer according to a modification of the fourth embodiment of the present invention. 
         FIG.  12    is a schematic plan view illustrating a content filling system according to a fifth embodiment of the present invention. 
         FIG.  13    is a schematic cross-sectional view (cross-sectional view taken along the line XIII-XIII in  FIG.  12   ) illustrating a sterilant atomizing wheel of a cap sterilizer according to the fifth embodiment of the present invention. 
         FIG.  14    is a schematic cross-sectional view (cross-sectional view taken along the line XIV-XIV in  FIG.  12   ) illustrating an air rinse wheel of the cap sterilizer according to the fifth embodiment of the present invention. 
         FIG.  15    is a schematic plan view illustrating a content filling system according to a modification (Modification 1) of the fifth embodiment of the present invention. 
         FIG.  16    is a schematic plan view illustrating a content filling system according to a modification (Modification 2) of the fifth embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
     A first embodiment of the present invention will be described below with reference to  FIGS.  1  to  6   .  FIGS.  1  to  6    illustrate one embodiment of the present invention. In the following drawings, the same reference numerals are assigned to the same components, and some detailed descriptions may be omitted. 
     (Content Filling System) 
     First, a content filling system (sterile filling system, aseptic filling system) according to the present embodiment will be described with reference to  FIG.  1   . 
     A content filling system  10  illustrated in  FIG.  1    is a system for filling a bottle (container)  30  with a content such as a beverage. The bottle  30  can be made by performing biaxial stretching blow molding on a preform made by performing injection molding on a synthetic resin material. A material of the bottle  30  to be used is preferably a thermoplastic resin, in particular, polyethylene (PE), polypropylene (PP), polyethylene-terephthalate (PET), or polyethylene naphthalate (PEN). In addition, the container may be glass, a can, paper, a pouch, or a composite container of these. The present embodiment will describe an example of a case where a bottle is used for the container. 
     As illustrated in  FIG.  1   , the content filling system  10  includes a bottle feeding portion  21 , a sterilizer  11 , an air rinse device  14 , a sterile water rinse device  15 , a filling device (filler)  20 , a cap attachment device (a capper, a seamer, and a capping machine)  16 , and a product bottle conveyor  22 . These bottle feeding portion  21 , sterilizer  11 , air rinse device  14 , sterile water rinse device  15 , filling device  20 , cap attachment device  16 , and product bottle conveyor  22  are disposed in this order along a conveying direction of the bottle  30  from an upstream side to a downstream side. Between the sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , and the cap attachment device  16 , a plurality of convey wheels  12  for conveying the bottle  30  between these devices is provided. 
     The bottle feeding portion  21  successively receives the empty bottle  30  from an outside to the content filling system  10 , and conveys the received bottle  30  to the sterilizer  11 . 
     A bottle molding portion (not illustrated) which molds the bottle  30  by performing biaxial stretching blow molding on a preform may be provided on the upstream side of the bottle feeding portion  21 . As described above, the process starting upon feeding of the preform, and then molding of the bottle  30 , and ending upon filling of the bottle  30  with the content and capping may be performed continuously. In this case, instead of the bottle  30  having a large volume, a preform having a small volume can be carried from the outside to the content filling system  10 , so that equipment constituting the content filling system  10  can be reduced in size. 
     The sterilizer  11  sterilizes the interior of the bottle  30  by injecting a sterilant into the bottle  30 . As the sterilant, a hydrogen peroxide aqueous solution is used, for example. In the sterilizer  11 , after a hydrogen peroxide aqueous solution having a concentration of 1% by weight or more, preferably 35% by weight is temporarily vaporized, condensed mist or gas is generated, and the mist or gas is sprayed on inner and outer surfaces of the bottle  30 . Since the inside of the bottle  30  is thus sterilized by the mist or gas of the hydrogen peroxide aqueous solution, the inner surface of the bottle  30  is sterilized uniformly. 
     The air rinse device  14  supplies sterile heated air or room temperature air into the bottle  30  to remove foreign matter, hydrogen peroxide, and the like from the inside of the bottle  30  while activating the hydrogen peroxide. 
     The sterile water rinse device  15  washes the bottle  30 , sterilized by hydrogen peroxide as a sterilant, with sterilized water at 15° C. to 85° C. As a result, hydrogen peroxide adhering to the bottle  30  is washed off, and foreign matter is removed. 
     The filling device  20  fills the previously sterilized content from a mouth of the bottle  30  into the bottle  30 . This filling device  20  fills the content in the empty bottle  30 . In the filling device  20 , while a plurality of the bottles  30  is rotated (revolved), the content is filled inside the bottles  30 . This content may be filled inside the bottle  30  at room temperature. The content is sterilized by heating or the like in advance, cooled to room temperature of 3° C. or more and 40° C. or less, and then filled inside the bottle  30 . Examples of contents to be filled by the filling device  20  include beverages such as tea-type beverages and milk-type beverages. 
     The cap attachment device  16  caps the bottle  30  by attaching the cap  33  to the mouth of the bottle  30  filled with the content by the filling device  20 . In the cap attachment device  16 , the mouth of the bottle  30  is capped with the cap  33  and then sealed so as to prevent external air or virus from invading into the bottle  30 . In the cap attachment device  16 , while the plurality of bottles  30  filled with the content rotates (revolves), the caps  33  are attached to the mouths of the bottles  30 . Thus, by attaching the cap  33  to the mouth of the bottle  30 , it is possible to obtain the product bottle  35 . 
     The cap  33  is sterilized by the cap sterilizer  50  in advance. The cap sterilizer  50  is disposed outside a sterile chamber  13  (to be described later) and near the cap attachment device  16 , for example. In the cap sterilizer  50 , a large number of the caps  33  carried in from the outside are preliminarily collected and then conveyed in a row toward the cap attachment device  16 . Mist or gas of hydrogen peroxide is blown against inner and outer surfaces of the cap  33  on the way of conveyance of the cap  33  toward the cap attachment device  16  and then the cap  33  is dried with hot air and sterilized. The configuration of the cap sterilizer  50  thus configured will be described later. 
     The product bottle conveyor  22  continuously conveys the product bottle  35  with the cap  33  attached by the cap attachment device  16  to the outside of the content filling system  10 . 
     In addition, the content filling system  10  includes the sterile chamber  13 . The sterile chamber  13  houses the sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , and the cap attachment device  16 , which have been described above. This content filling system  10  may be, for example, a sterile filling system. In this case, the interior of the sterile chamber  13  is kept in a sterile state. 
     Alternatively, the content filling system  10  may be a high temperature filling system that fills a content at a high temperature of 85° C. or more and less than 100° C. The content filling system  10  may also be a medium temperature filling system that fills a content at a medium temperature of 55° C. or more and less than 85° C. 
     (Cap Sterilizer) 
     Next, the configuration of the cap sterilizer  50  described above will be described with reference to  FIG.  2   .  FIG.  2    is a schematic front view illustrating the cap sterilizer  50  according to the present embodiment. In  FIG.  2   , a paper surface upward direction indicates upward in a vertical direction, and a paper surface downward direction indicates downward in the vertical direction. 
     As illustrated in  FIG.  2   , the cap sterilizer  50  includes a first infeed (introduction) chamber  51 , a second infeed (introduction) chamber  52 , a sterilant atomizing (disinfectant spray) chamber  53 , an air rinse chamber  54 , and a washing chamber  55 . The first infeed chamber  51 , the second infeed chamber  52 , the sterilant atomizing chamber  53 , the air rinse chamber  54 , and the washing chamber  55  are arranged in this order along the conveying direction of the cap  33 . The chambers  51 ,  52 ,  53 ,  54 , and  55  are arranged inside a housing  60 . 
     The first infeed chamber  51  and the second infeed chamber  52  are separated by a partition wall  61  provided therebetween. Likewise, the second infeed chamber  52  and the sterilant atomizing chamber  53  are separated by a partition wall  62 , the second infeed chamber  52  and the air rinse chamber  54  are separated by a partition wall  63 , and the sterilant atomizing chamber  53  and the air rinse chamber  54  are separated by a partition wall  64 . In addition, the air rinse chamber  54  and the washing chamber  55  are separated by a partition wall  65 . 
     The partition walls  61 ,  62 ,  63 ,  64 , and  65  prevent gas, water, and the like from flowing between the chambers  51 ,  52 ,  53 ,  54 , and  55  and play a role of stabilizing the pressures in the chambers  51 ,  52 ,  53 ,  54 , and  55 . However, gaps are formed in the respective partition walls  61 ,  62 ,  63 ,  64 , and  65  so that the cap  33  or the like can pass therethrough. The size of each gap is decreased to the minimum, for example, a comparable size to the cap  33 , so that the pressures in the chambers  51 ,  52 ,  53 ,  54 , and  55  do not change. 
     A hopper  56 , a sorter  57 , and a cap inspection machine  58  are provided on the previous process side of the first infeed chamber  51  and outside the housing  60 . A large number of the caps  33  are randomly charged into the hopper  56  from the outside. The sorter  57  arranges the caps  33 , randomly charged into the hopper  56 , in one row or multiple rows and conveys the caps  33  from a lower side to an upper side in the vertical direction. The cap inspection machine  58  inspects the shape and the like of each of the caps  33  and discharges the caps  33  failed in inspection. The caps  33  which have passed the inspection are conveyed in a row toward the first infeed chamber  51 . 
     The cap  33  is a well-known one and has a substantially circular planar shape with an opening on the inner surface side. As the cap  33 , one formed of a thermoplastic resin such as high density polyethylene (HDPE), polypropylene (PP), and biodegradable plastic can be used. As the cap  33 , in addition to a normal bottle cap, a composite cap or a sport cap may be used. 
     In the first infeed chamber  51  and the second infeed chamber  52 , a conveyance guide  70  for conveying a plurality of the caps  33  in a row is provided. The conveyance guide  70  may include, for example, a plurality of rails. In this case, a space is formed in a region surrounded by the plurality of rails so that the cap  33  does not come off, and the cap  33  is accommodated in this space and conveyed. The cap  33  is transferred from the first infeed chamber  51  side toward the second infeed chamber  52  by its own weight. By providing the conveyance guide  70  thus configured, it is possible to convey the cap  33  at high speed from the first infeed chamber  51  to the second infeed chamber  52 . 
     The second infeed chamber  52 , the sterilant atomizing chamber  53 , the air rinse chamber  54 , and the washing chamber  55  include respectively rotation conveyance mechanisms  71  to  76  for rotating and conveying the caps  33 . Among them, the first rotation conveyance mechanism  71  is provided in the second infeed chamber  52 , and the second rotation conveyance mechanism  72  is provided in the sterilant atomizing chamber  53 . The air rinse chamber  54  and the washing chamber  55  include a total of four rotation conveyance mechanisms  73  to  76  (a third rotation conveyance mechanism  73 , a fourth rotation conveyance mechanism  74 , a fifth rotation conveyance mechanism  75 , a sixth rotation conveyance mechanism  76 ). Among them, the three rotation conveyance mechanisms  73  to  75  are arranged inside the air rinse chamber  54 , and the sixth rotation conveyance mechanism  76  is disposed to straddle the air rinse chamber  54  and the washing chamber  55 . The rotation conveyance mechanisms  71  to  76  each rotate (on their axes) along axes parallel to the horizontal direction, thereby rotating (revolving) and conveying a plurality of the caps  33 . The rotation conveyance mechanisms  71  to  76  each have a star wheel located at the center and provided with a notch for accommodating the cap  33  and a plurality of rails arranged around the star wheel and preventing the cap  33  from coming off. The cap  33  is conveyed as the star wheel is driven, guided by the rail, accommodated, and rotated (revolved). By using the rotation conveyance mechanisms  71  to  76  thus configured, it is possible to convey the cap  33  at high speed within the cap sterilizer  50 . 
     A drainage pipe  67  is formed on a bottom surface  66  of the housing  60  and inside the second infeed chamber  52 . The bottom surface  66  is inclined downward from the washing chamber  55  toward the second infeed chamber  52 . Due to this, droplets generated inside the housing  60  due to condensation or the like can be discharged to the outside of the housing  60  through the drainage pipe  67 . The drainage pipe  67  is curved partway in an S shape, and a drainage remains in the S-shaped portion, whereby an internal pressure of the second infeed chamber  52  is maintained (water sealing mechanism). 
     Next, the configuration of each of the chambers  51 ,  52 ,  53 ,  54 , and  55  will be further described. 
     The cap  33  from the cap inspection machine  58  is introduced into the first infeed chamber  51 , and the first infeed chamber  51  is disposed above the second infeed chamber  52 . The interior of the first infeed chamber  51  is maintained at a negative pressure or a slight positive pressure (for example, −100 Pa or more and 10 Pa or less), so that a steam containing a sterilant is prevented from leaking to the outside of the housing  60 . The first infeed chamber  51  is provided mainly to prevent the steam containing the sterilant from leaking to the outside, so that the volume of the first infeed chamber  51  may be smaller than the volume of the second infeed chamber  52 . Unlike the second infeed chamber  52 , the first infeed chamber  51  is not provided with a rotation conveyance mechanism for rotating and conveying the cap  33 . 
     The cap  33  is fed from the first infeed chamber  51  to the second infeed chamber (infeed chamber)  52  by the conveyance guide  70 . Sterile hot air from a first hot air supplier  79  is sent into the second infeed chamber  52 . The temperature of sterile hot air is, for example, 40° C. or more and 120° C. or less. Thus, the interior of the second infeed chamber  52  is maintained at a temperature of, for example, 30° C. or more and 80° C. or less. This suppresses condensation of the sterilant inside the second infeed chamber  52  and can prevent variation in the extent of sterilization among the plurality of caps  33  due to the fact that a liquid sterilant remains in the cap  33 . The interior of the second infeed chamber  52  is maintained at a positive pressure (for example, 0 Pa or more and 200 Pa or less), so that the sterilant is prevented from excessively flowing into the second infeed chamber  52 . Inside the second infeed chamber  52 , the conveyance guide  70  is provided with a first stopper  77  which is freely opened and closed. When the first stopper  77  is opened, the cap  33  is sent to the first rotation conveyance mechanism  71 , and when the first stopper  77  is closed, the cap  33  stays at this position. The first hot air supplier  79  may be disposed on a conveyance path of the first rotation conveyance mechanism  71 , and the temperature of the cap  33  may be preliminarily increased by hot air from the first hot air supplier  79 . 
     The sterilant atomizing chamber  53  sprays a sterilant against the cap  33  fed from the second infeed chamber  52  by the first rotation conveyance mechanism  71 . The sterilant atomizing chamber  53  is disposed above the second infeed chamber  52 . Depending on the positional relationship of the first rotation conveyance mechanism  71  and the like, the second infeed chamber  52  may be located above the sterilant atomizing chamber  53 . Here, the sterilant is, for example, hydrogen peroxide solution. The cap  33  sent from the first rotation conveyance mechanism  71  is delivered to the second rotation conveyance mechanism  72 , and while the cap  33  is conveyed by the second rotation conveyance mechanism  72 , the sterilant is sprayed by spray nozzles  81 A and  81 B. At the top of the sterilant atomizing chamber  53 , two sterilant spray devices  82 A and  82 B are arranged. Among the sterilant spray devices, the sterilant spray device  82 A is connected to the spray nozzle  81 A for outer surface which supplies the sterilant to the outer surface (top surface portion) side of the cap  33 . On the other hand, the other sterilant spray device  82 B is connected to the spray nozzle  81 B for inner surface which supplies the sterilant to the inner surface (opening) side of the cap  33 . 
     It is preferable that the spray nozzle  81 A for outer surface is located downstream of the spray nozzle  81 B for inner surface in the conveying direction of the cap  33  (the spray nozzle  81 A may be located upstream of the spray nozzle  81 B in the conveying direction of the cap  33 ). That is, it is preferable to first supply the sterilant to the inner surface of the cap  33  by the spray nozzle  81 B on the conveyance path of the second rotation conveyance mechanism  72 , and then supply the sterilant to the outer surface of the cap  33  by the spray nozzle  81 A. Thus, it is possible to sterilize the inner surface of the cap  33 , which needs to be more reliably sterilized, prior to the outer surface of the cap  33 . In order to adhere the sterilant to every corner of a complicated shape of the inner surface of the cap  33  conveyed at high speed, the spray nozzles  81 A and  81 B have an inner diameter of φ 2 mm or more and φ 15 mm or less (preferably φ 3 mm or more and φ 10 mm or less) and preferably have an outer diameter of 2 mm or more (preferably 4 mm or more) thicker than the inner diameter so as to prevent reduction in temperature of hydrogen peroxide gas and occurrence of liquid sagging. If the nozzle inner diameter is less than φ 2 mm, a stabilizer of hydrogen peroxide accumulates during long-term use, which may clog the nozzle. A distance between the cap  33  and the tips of the spray nozzles  81 A and  81 B is preferably 5 mm or more and 100 mm or less. 
     A cover  83  having a fan or arc-shape as viewed from the front side, for example, is disposed at an upper portion of the second rotation conveyance mechanism  72  and around the spray nozzles  81 A and  81 B. The cover  83  covers the surroundings of the spray nozzles  81 A and  81 B, prevents the sterilant from the spray nozzles  81 A and  81 B from scattering to the surroundings, and enables effective spraying of the sterilant to the cap  33 . The interior of the sterilant atomizing chamber  53  is maintained at a positive pressure (for example, 0 Pa or more and 50 Pa or less), whereby the sterilant is prevented from excessively flowing out of the sterilant atomizing chamber  53 . An adhesion amount of hydrogen peroxide necessary for sterilizing the cap  33  is 0.6 μL/cm 2  or more and 4.7 μL/cm 2  or less (preferably 1.2 μL/cm 2  or more and 2.4 μL/cm 2  or less) in terms of 35% by weight. Within this range, the cap  33  can be sterilized at high speed, and a medicine can be reliably removed by air rinsing to be described later. 
       FIG.  3    illustrates a vertical cross section of the interior of the sterilant atomizing chamber  53 . As illustrated in  FIG.  3   , the cover  83  is disposed inside the sterilant atomizing chamber  53 . The cover  83  has a front plate  83   a , a top plate  83   b , a rear plate  83   c , and a bottom plate  83   d  which are connected to each other. Among them, the front plate  83   a  has a fan or arc-shape when viewed from the front side and is larger than the rear plate  83   c . The front plate  83   a  may have a transparent confirmation window so that the interior of the cover  83  can be visually observed. The spray nozzle  81 B for inner surface extends from the front plate  83   a  toward the interior of the cover  83 , and the spray nozzle  81 A for outer surface extends from the rear plate  83   c  toward the interior of the cover  83 . In  FIG.  3   , the spray nozzle  81 B is located on the front side (the upstream side in the conveying direction of the cap  33 ) with respect to the spray nozzle  81 A. As described above, in the space surrounded by the cover  83 , the sterilant is sprayed against the cap  33  from the spray nozzles  81 A and  81 B. At this time, since the concentration of the sterilant inside the cover  83  can be increased, the cap  33  can be effectively sterilized. Since the tips of the spray nozzles  81 A and  81 B are covered with the cover  83 , the amount of the sterilant leaking to the outside of the cover  83  is reduced, whereby the amount of the sterilant leaking to the outside of the sterilant atomizing chamber  53  can also be reduced. 
     A washing nozzle  93  which ejects a washing liquid toward the interior of the cover  83  is provided inside the cover  83 . In this case, the washing nozzle  93  is disposed so as to face upward between the front plate  83   a  and the second rotation conveyance mechanism  72 . Examples of the washing liquid ejected from the washing nozzle  93  include a single preparation or a mixed preparation containing components such as water, an alkaline solution, alcohol, chlorine, peracetic acid, and hydrogen peroxide and sterile water used to wash away a medicine after washing/sterilization. As described above, by ejecting the washing liquid from the washing nozzle  93 , it is possible to wash equipment in the cover  83  before sterilizing the cap  33 . For example, an inner wall surface of the cover  83 , the spray nozzles  81 A and  81 B, the second rotation conveyance mechanism  72 , and the like can be washed. Consequently, it is possible to effectively perform, for example, Cleaning out of Place (COP) treatment or Sterilizing out of Place (SOP) treatment on the sterilant atomizing chamber  53 . 
       FIG.  4    illustrates a modification of the sterilant atomizing chamber  53 . As illustrated in  FIG.  4   , the spray nozzles  81 A and  81 B are arranged at substantially the same position when viewed from the front side (left side in  FIG.  4   ). In this case, the spray nozzles  81 A and  81 B spray the sterilant against the inner and outer surfaces of the cap  33  at substantially the same timing. A sterilant spray device  82 C is provided above the sterilant atomizing chamber  53 , and a sterilant is supplied to both of the spray nozzles  81 A and  81 B from the sterilant spray device  82 C. In this case, since the positions of the spray nozzles  81 A and  81 B can be made substantially the same in the conveying direction of the cap  33 , the sterilant atomizing chamber  53  can be compactly configured. 
       FIG.  5    illustrates another modification of the sterilant atomizing chamber  53 . In  FIG.  5   , the three spray nozzles  81 B,  81 A, and  81 B spray the sterilant against the cap  33 . That is, the spray nozzle  81 B for inner surface, the spray nozzle  81 A for outer surface, and the spray nozzle  81 B for inner surface are arranged in this order from the upstream side in the conveying direction of the cap  33  to the downstream side. Thus, it is possible to spray a relatively large amount of the sterilant against the inner surface of the cap  33  which needs to be more reliably sterilized. In this case, it is possible to increase the conveying speed of the cap  33 , for example, to about 800 cpm or more and 1500 cpm or less. 
     As the sterilant, besides hydrogen peroxide, alcohols such as peracetic acid, nitric acid, chlorine sterilant, sodium hydroxide, potassium hydroxide, ethyl alcohol, and isopropyl alcohol, chlorine dioxide, ozone water, acid water, and surfactant may be used alone, or two or more of these may be used in combination at any ratio. 
     Referring again to  FIG.  2   , the air rinse chamber  54  air-rinses the cap  33  sprayed with the sterilant in the sterilant atomizing chamber  53 . The cap  33  is sequentially conveyed by the rotation conveyance mechanisms  73  to  76  in the air rinse chamber  54 , and meanwhile, sterile hot air is blown against both the inner and outer surfaces of the cap  33 . Sterile hot air from a second hot air supplier  80  is sent into the air rinse chamber  54 . In this case, sterile hot air is blown against the cap  33  passing through the fourth rotation conveyance mechanism  74 . Sterile hot air may be blown against the cap  33  passing through the fifth rotation conveyance mechanism  75  and/or the sixth rotation conveyance mechanism  76 . The temperature of sterile hot air is, for example, 80° C. or more and 140° C. or less, preferably 90° C. or more and 120° C. or less. The air volume of sterile hot air is, for example, 5 m 3 /min or more and 20 m 3 /min or less. The sterile hot air blowing time is 1 second or more and 20 seconds or less, preferably 3 seconds or more and 14 seconds or less. By blowing sterile hot air against the cap  33 , the temperature of the cap  33  is raised to 40° C. or more, preferably 50° C. or more. As a result, the sterilant adhering to the cap  33  is removed. The interior of the air rinse chamber  54  is maintained at a positive pressure (for example, 30 Pa or more and 200 Pa or less, preferably 50 Pa or more and 150 Pa or less). Sterile hot air may contain a trace amount of a component of a sterilant such as hydrogen peroxide. 
       FIG.  6    illustrates a vertical cross section of the interior of the air rinse chamber  54 . As illustrated in  FIG.  6   , air rinse nozzles  94 A and  94 B are arranged inside the air rinse chamber  54 . The air rinse nozzles  94 A and  94 B are connected to the second hot air supplier  80  and each blow out sterile hot air supplied from the second hot air supplier  80 . Among the air rinse nozzles, the air rinse nozzle  94 A blows sterile hot air against the outer surface of the cap  33 , and the air rinse nozzle  94 B blows sterile hot air against the inner surface of the cap  33 . The air rinse nozzles  94 A and  94 B are arranged at substantially the same position when viewed from the front side (left side in  FIG.  6   ). In this case, the air rinse nozzles  94 A and  94 B spray sterile hot air against the inner and outer surfaces of the cap  33  at substantially the same timing. As described above, in the space surrounded by the air rinse chamber  54 , sterile hot air is blown against both the inner and outer surfaces of the cap  33  from the air rinse nozzles  94 A and  94 B. Thus, it is possible to reliably remove the sterilant adhering to the inner surface and the outer surface of the cap  33  in the sterilant atomizing chamber  53 . 
     Referring to  FIG.  2   , the washing chamber  55  washes the cap  33  which has been air-rinsed in the air rinse chamber  54 . The cap  33  is conveyed by the sixth rotation conveyance mechanism  76  in the washing chamber  55 . Meanwhile, first, a washing liquid such as sterile water is blown against the inner and outer surfaces of the cap  33  by the washing nozzle  84 . As a result, even when foreign matter is adhering to the cap  33 , it is possible to reliably remove the foreign matter and to cool the cap  33  heated with sterile hot air. Then, sterile air is blown against the inner and outer surfaces of the cap  33  by the air blow nozzle  85 , and the washing liquid such as sterile water adhering to the cap  33  is removed. Even after the sterile air is blown, sterile water slightly remains in the cap  33 . This makes it possible to improve lubrication between the cap  33  and a chute  59  to be described later while the cap  33  is conveyed by the chute  59  and to prevent the temperature of the cap  33  from rising due to frictional heat with the chute  59 . By suppressing the rise in the temperature of the cap  33  as described above, it is possible to stably perform seaming operation of the cap  33  in the cap attachment device  16 . The interior of the washing chamber  55  is maintained at a positive pressure (for example, Pa or more and 200 Pa or less). This prevents an atmosphere containing a sterilant from flowing out toward the cap attachment device  16 . In the present embodiment, the washing chamber  55  is not necessarily provided. When a lubricant adheres to the cap  33 , such as when a carbonic acid cap is used as the cap  33 , the washing nozzle  84  may be temporarily stopped so that the lubricant does not peel off. 
     The chute  59  for conveying the cap  33  toward the cap attachment device  16  is connected to the washing chamber  55 . The chute  59  may include, for example, a plurality of rails. In this case, a space is formed in a region surrounded by the plurality of rails so that the cap  33  does not come off, and the cap  33  is accommodated in this space and conveyed. In the washing chamber  55 , the chute  59  is provided with an openable and closable second stopper  78 . When the second stopper  78  is opened, the cap  33  is sent to the cap attachment device  16  by the chute  59 . On the other hand, when the second stopper  78  is closed, the cap  33  stays at this position. Alternatively, the second stopper  78  may be provided on the chute  59  and near the cap attachment device  16 . 
     In the present embodiment, exhaust pipes  86 A to  86 E are connected respectively to the first infeed chamber  51 , the second infeed chamber  52 , the sterilant atomizing chamber  53 , the air rinse chamber  54 , and the washing chamber  55 . The first infeed chamber  51 , the second infeed chamber  52 , the sterilant atomizing chamber  53 , the air rinse chamber  54 , and the washing chamber  55  are exhausted via the respective exhaust pipes  86 A to  86 E. A blower  68  which draws gas in the exhaust pipes  86 A to  86 E is connected to the exhaust pipes  86 A to  86 E, and a scrubber  69  which processes components of a sterilant of the gas is connected to the blower  68 . 
     In this case, the exhaust pressure E 4  in the air rinse chamber  54  is higher than the exhaust pressure E 1  in the first infeed chamber  51 . As a result, even if a large air volume of sterile hot air is supplied to the air rinse chamber  54 , air is sucked from the air rinse chamber  54 , and it is possible to prevent the pressure in the air rinse chamber  54  from excessively increasing. 
     The exhaust pressure E 5  in the washing chamber  55  is higher than the exhaust pressure E 1  in the first infeed chamber  51 . This makes it possible to strongly suck a gas containing a sterilant from the washing chamber  55  and to prevent the atmosphere containing the sterilant from flowing out toward the cap attachment device  16 . 
     The exhaust pressure E 1  in the first infeed chamber  51  is higher than the exhaust pressure E 2  in the second infeed chamber  52 . This makes it possible to strongly suck a gas containing a sterilant from the first infeed chamber  51  and to prevent the atmosphere containing the sterilant from flowing out of the housing  60 . 
     The exhaust pressure E 2  in the second infeed chamber  52  is higher than the exhaust pressure E 3  in the sterilant atomizing chamber  53 . That is, the exhaust pressure E 3  in the sterilant atomizing chamber  53  is lower than any of the exhaust pressures E 1 , E 2 , E 4 , and E 5  of the other chambers  51 ,  52 ,  54 , and  55 . The sterilant atomizing chamber  53  is not necessarily exhausted (the exhaust pressure may be 0). As a result, the gas containing the sterilant stays in the second infeed chamber  52 , and it is possible to prevent the gas containing the sterilant from condensing in the second infeed chamber  52 . On the other hand, the exhaust pressure E 3  in the sterilant atomizing chamber  53  is sufficiently weakened, or the interior of the sterilant atomizing chamber  53  is not exhausted, whereby the concentration of the sterilant is increased in the atmosphere of the sterilant atomizing chamber  53 , and the cap  33  can be reliably sterilized in the sterilant atomizing chamber  53 . By increasing the concentration of the sterilant in the sterilant atomizing chamber  53 , even when the cap  33  is conveyed at high speed, the cap  33  can be sterilized reliably. 
     In summary, a relationship E 5 , E 4 &gt;E 1 &gt;E 2 &gt;E 3  holds. The relationship between E 5  and E 4  does not matter. If the positive pressure of the cap sterilizer  50  is higher than the positive pressure of a capper portion of a filling chamber of the filling device  20 , the cap  33  can be conveyed well. Specifically, it is better to increase the positive pressure of the cap sterilizer  50  higher by 30 Pa or more and 200 Pa or less than the positive pressure of the filling chamber. When a differential pressure of 200 Pa or more is provided, sterilant gas (hydrogen peroxide) from the cap sterilizer  50  flows into the filling chamber, and there is a risk that the sterilant will dissolve in a product liquid at a filling valve opening. 
     Throughout the cap sterilizer  50 , the conveying speed of the cap  33  is 100 cpm or more and 1500 cpm or less, preferably 500 cpm or more and 1000 cpm or less. According to the cap sterilizer  50  according to the present embodiment, even when the cap  33  is conveyed at high speed as described above, the cap  33  can be sterilized reliably. The number of the caps  33  passing through a predetermined position per minute is represented by cap per minute (cpm). When the filling speed of the bottle  30  is slow, such as when the bottle  30  is a large size bottle (having an inner capacity of 1 L or more), the conveying speed of the cap  33  may be made slower than the above speed in accordance with this filling speed. In this case, supply conditions (temperature, flow rate, etc.) of hot air in the second infeed chamber  52  and the air rinse chamber  54  may be adjusted so that the temperature of the cap  33  does not rise. 
     In the present embodiment, the case in which the two chambers, the first infeed chamber  51  and the second infeed chamber  52 , are provided as infeed chambers has been described as an example, but the present invention is not limited to this example. A single infeed chamber may be provided by combining the first infeed chamber  51  and the second infeed chamber  52 . Further, in the present embodiment, the case in which rotary shafts of the rotation conveyance mechanisms  71  to  76  are oriented in the horizontal direction so that the cap  33  is conveyed in a substantially vertical plane has been described as an example. However, the present invention is not limited to this example, and the rotary shafts of the rotation conveyance mechanisms  71  to  76  may be oriented in the vertical direction so that the cap  33  is conveyed in a substantially horizontal plane. 
     (Content Filling Method) 
     Next, a content filling method using the above-described content filling system  10  ( FIG.  1   ) will be described. In the following description, a filling method at a normal time, that is, a content filling method in which a content such as a beverage is filled inside the bottle  30  to produce the product bottle  35  will be described. 
     First, the plurality of empty bottles  30  is sequentially fed from the outside of the content filling system  10  to the bottle feeding portion  21 . The bottle  30  is sent from the bottle feeding portion  21  to the sterilizer  11  by the convey wheel  12  (container feeding step). 
     Then, in the sterilizer  11 , the bottle  30  is sterilized using a hydrogen peroxide aqueous solution as a sterilant (bottle sterilization step). At this time, the hydrogen peroxide aqueous solution is a gas or mist condensed after a hydrogen peroxide aqueous solution having a concentration of 1% by weight or more, preferably 35% by weight is temporarily vaporized, and the mist or gas is supplied toward the bottle  30 . 
     Subsequently, the bottle  30  is sent to the air rinse device  14  by the convey wheel  12 , and sterile heated air or room temperature air is supplied in the air rinse device  14 , whereby foreign matter, hydrogen peroxide, and the like are removed from the bottle  30  while hydrogen peroxide is activated. Subsequently, the bottle  30  is conveyed to the sterile water rinse device  15  by the convey wheel  12 . In the sterile water rinse device  15 , washing with sterile water at 15° C. to 85° C. is performed (rinsing step). Specifically, sterile water at 15° C. to 85° C. is supplied into the bottle  30  at a flow rate of 5 L/min or more and 15 L/min or less. At this time, preferably, the bottle  30  takes an inverted attitude, and the sterile water is supplied into the bottle  30  through the downwardly opened mouth, and flows out of the bottle  30  from the mouth. With this sterile water, hydrogen peroxide adhering to the bottle  30  is washed off, and foreign matter is removed. The step of supplying sterile water into the bottle  30  is not necessarily provided. 
     Subsequently, the bottle  30  is conveyed to the filling device  20  by the convey wheel  12 . In the filling device  20 , while the bottle  30  is rotated (revolved), the content is filled inside the bottle  30  from the mouth (filling step). In the filling device  20 , the contents are prepared in advance, and the content heated and sterilized and then cooled to the room temperature is filled inside the sterilized bottle  30  at the room temperature. 
     Subsequently, the bottle  30  filled with the content is conveyed to the cap attachment device  16  by the convey wheel  12 . 
     On the other hand, the cap  33  is sterilized by the cap sterilizer  50  illustrated in  FIG.  2    in advance (cap sterilization step). Meanwhile, first, a large number of the caps  33  are randomly charged into the hopper  56  from the outside of the cap sterilizer  50 . Then, the caps  33  randomly charged into the hopper  56  are aligned by the sorter  57  and then conveyed to the cap inspection machine  58 . Then, in the cap inspection machine  58 , the shape and the like of each of the caps  33  are inspected, and the caps  33  which have passed the inspection are conveyed in a row toward the first infeed chamber  51 . 
     The cap  33  introduced into the first infeed chamber  51  is sent to the second infeed chamber  52  by the conveyance guide  70 . As described above, the interior of the second infeed chamber  52  is maintained at, for example, 30° C. or more and 80° C. or less by sterile hot air. Then, the cap  33  is conveyed in the second infeed chamber  52  by the first rotation conveyance mechanism  71  and sent to the sterilant atomizing chamber  53 . Subsequently, in the sterilant atomizing chamber  53 , while the cap  33  is conveyed by the second rotation conveyance mechanism  72 , a sterilant such as a hydrogen peroxide solution is sprayed from the spray nozzles  81 A and  81 B, and the inner and outer surfaces of the cap  33  are sterilized. 
     Subsequently, the cap  33  sprayed with the sterilant is sent to the air rinse chamber  54 . 
     In the air rinse chamber  54 , the cap  33  is sequentially conveyed by the rotation conveyance mechanisms  73  to  76  in the air rinse chamber  54 , and meanwhile, sterile hot air is blown against the inner and outer surfaces of the cap  33 . As a result, the sterilant adhering to the cap  33  is air-rinsed. 
     Then, the cap  33  is sent from the air rinse chamber  54  to the washing chamber  55 . In the washing chamber  55 , while the cap  33  is conveyed by the sixth rotation conveyance mechanism  76 , a washing liquid such as sterile water is blown against the cap  33  by the washing nozzle  84 , and foreign matter and the like adhering thereto are removed and cooled. Subsequently, sterile air is blown against the cap  33  by the air blow nozzle  85 , and sterile water is removed. At this time, sterile water adhering to the cap  33  is not completely removed, but a part of sterile water is left. This makes it possible to prevent the temperature of the cap  33  from rising due to frictional heat with the chute  59  and to stably perform seaming operation of the cap  33  in the cap attachment device  16 . Since a trace amount of sterile water remains, the sterile water is removed by, for example, the frictional heat described above by the time the cap  33  reaches the cap attachment device  16 . 
     Thereafter, the cap  33  is carried from the washing chamber  55  and sent to the cap attachment device  16  by the chute  59 . 
     Referring again to  FIG.  1   , the cap  33  sterilized by the cap sterilizer  50  as described above is attached to the mouth of the bottle  30  which has been conveyed from the filling device  20  in the cap attachment device  16 . Consequently, the product bottle  35  having the bottle  30  and the cap  33  is obtained (cap attaching step). 
     Thereafter, the product bottle  35  is conveyed from the cap attachment device  16  to the product bottle conveyor  22  and is carried toward the outside of the content filling system  10 . 
     The respective steps from the sterilization step to the cap attachment step are performed in a sterile atmosphere surrounded by the sterile chamber  13 , that is, in a sterile environment. After the sterilization treatment, aseptic air of positive pressure is supplied into the sterile chamber  13  so that the aseptic air is always blown toward the exterior of the sterile chamber  13 . 
     The production (conveying) speed of the bottle  30  in the content filling system  10  is preferably 100 bpm or more and 1500 bpm or less. Here, the conveying speed of the bottle  30  per minute is represented by bottle per minute (bpm). 
     As described above, according to the present embodiment, the cap sterilizer  50  is divided into the plurality of chambers  51 ,  52 ,  53 ,  54 , and  55 , and the pressure in each of the chambers  51 ,  52 ,  53 ,  54 , and  55  is controlled. Thus, while the cap  33  is conveyed at high speed in the cap sterilizer  50 , the cap  33  can be reliably sterilized. 
     Specifically, the exhaust pressure E 4  in the air rinse chamber  54  is higher than the exhaust pressure E 1  in the first infeed chamber  51 . As a result, even if a large air volume of sterile hot air is supplied to the air rinse chamber  54  in order to reliably air-rinse the cap  33  conveyed at high speed, sterile hot air can be removed from the air rinse chamber  54  without being left. 
     The exhaust pressure E 1  in the first infeed chamber  51  is higher than the exhaust pressure E 2  in the second infeed chamber  52 . As a result, even if the concentration of the sterilant in the sterilant atomizing chamber  53  is increased in order to reliably sterilize the cap  33  conveyed at high speed, it is possible to prevent the atmosphere containing the sterilant from flowing out of the housing  60 . 
     Both the exhaust pressure E 2  in the second infeed chamber  52  and the exhaust pressure E 4  in the air rinse chamber  54  are higher than the exhaust pressure E 3  in the sterilant atomizing chamber  53 , or the sterilant atomizing chamber  53  is not exhausted. As a result, the concentration of the sterilant can be increased in the sterilant atomizing chamber  53 , and the cap  33  conveyed at high speed can be sterilized reliably. 
     Further, according to the present embodiment, the exhaust pressure E 5  in the washing chamber  55  is higher than the exhaust pressure E 1  in the first infeed chamber  51 . This makes it possible to prevent the atmosphere containing the sterilant from flowing out toward the cap attachment device  16  from the washing chamber  55 . 
     Furthermore, according to the present embodiment, by exhausting the chambers  51 ,  52 ,  53 ,  54 , and  55 , it is possible to prevent the internal pressure of each of the chambers  51 ,  52 ,  53 ,  54 , and  55  from becoming too high. As a result, the cap  33  can be reliably introduced into each of the chambers  51 ,  52 ,  53 ,  54 , and  55 . On the other hand, if the chambers  51 ,  52 ,  53 ,  54 , and  55  are not sufficiently exhausted, the internal pressure of each of the chambers  51 ,  52 ,  53 ,  54 , and  55  becomes too high, so that the cap  33  may be unable to enter  51 ,  52 ,  53 ,  54 , and  55 . 
     Further, according to the present embodiment, the first infeed chamber  51  into which the cap  33  is introduced, the second infeed chamber  52  into which sterile hot air is sent, and the sterilant atomizing chamber  53  which sprays the sterilant against the cap  33  are arranged in this order along the conveying direction of the cap  33 . The first infeed chamber  51  and the second infeed chamber  52  are separated from each other by the partition wall  61 . As a result, even when the concentration of the sterilant in the sterilant atomizing chamber  53  is increased, steam containing the sterilant from the sterilant atomizing chamber  53  is prevented from leaking to the outside of the cap sterilizer  50 . Accordingly, since the concentration of the sterilant in the sterilant atomizing chamber  53  can be increased, even when the conveying speed of the cap  33  is increased, the cap  33  can be sterilized reliably. 
     Further, according to the present embodiment, the air rinse chamber  54  which air-rinses the cap  33  sprayed with the sterilant in the sterilant atomizing chamber  53  is provided. This makes it possible to reliably remove the sterilant adhering to the cap  33  in the sterilant atomizing chamber  53 . 
     Further, according to the present embodiment, since the internal pressure of the first infeed chamber  51  is maintained at −100 Pa or more and 10 Pa or less (negative pressure to slight positive pressure), it is possible to prevent steam containing the sterilant agent from leaking from the first infeed chamber  51  to the outside of the cap sterilizer  50 . On the other hand, since the internal pressure of the second infeed chamber  52  is maintained at 50 Pa or more and 200 Pa or less (positive pressure), the amount of the sterilant flowing into the second infeed chamber  52  from the sterilant atomizing chamber  53  can be suppressed, and it is possible to more reliably reduce the amount of the sterilant leaking from the second infeed chamber  52  to the outside of the cap sterilizer  50  via the first infeed chamber  51 . 
     Further, according to the present embodiment, the cover  83  covering the surroundings of the spray nozzles  81 A and  81 B is provided in the sterilant atomizing chamber  53 . As a result, the concentration of the sterilant inside the cover  83  can be increased, and the cap  33  can be effectively sterilized. As a result, even when the conveying speed of the cap  33  increases, the cap  33  can be reliably sterilized. Further, even when the concentration of the sterilant in the cover  83  is increased, it is possible to prevent steam containing the sterilant from leaking from the sterilant atomizing chamber  53  to the outside of the cap sterilizer  50 . 
     According to the present embodiment, the cover  83  has a fan or arc-shape when viewed from the front side. That is, the shape of the cover  83  corresponds to the shape of the second rotation conveyance mechanism  72 . This makes it possible to reduce the volume of a wasted space in the cover  83  and to efficiently increase the concentration of the sterilant inside the cover  83 . 
     Further, according to the present embodiment, the spray nozzle  81 A for outer surface is located downstream of the spray nozzle  81 B for inner surface in the conveying direction of the cap  33 . Thus, it is possible to lengthen the time during which the sterilant adheres to the inner surface of the cap  33  which needs to be more reliably sterilized and to sterilize the inner surface of the cap  33  more effectively. The spray nozzle  81 A may be located upstream of the spray nozzle  81 B in the conveying direction of the cap  33 . 
     Furthermore, according to the present embodiment, since the washing nozzle  93  which ejects a washing liquid toward the interior of the cover  83  is provided inside the cover  83 , before the cap  33  is sterilized, equipment inside the cover  83  can be washed. 
     Further, according to the present embodiment, in the air rinse chamber  54 , sterile hot air is blown against both the inner and outer surfaces of the cap  33  by the air rinse nozzles  94 A and  94 B. Thus, in the sterilant atomizing chamber  53 , the sterilant adhering to the inner and outer surfaces of the cap  33  can be reliably removed by the spray nozzles  81 A and  81 B. Accordingly, the high concentration of the sterilant can be blown against the cap  33  by the spray nozzles  81 A and  81 B, and as a result, the conveying speed of the cap  33  can be increased. 
     Particularly, as sterile hot air is blown by the air rinse nozzles  94 A and  94 B, the temperature of the cap  33  rises to 40° C. or more, so that the sterilant on the cap  33  can be reliably removed. 
     Furthermore, by providing the washing nozzle  84  which washes the cap  33  air-rinsed by the air rinse nozzles  94 A and  94 B, even when foreign matter adheres to the cap  33 , it is possible to reliably remove the foreign matter and to cool the cap  33  heated with sterile hot air. 
     Further, according to the present embodiment, in the washing chamber  55 , a washing liquid such as sterile water is blown against the cap  33  from the washing nozzle  84 , whereby the cap  33  is cleaned. This makes it possible to reliably remove foreign matter adhering to the cap  33 . In addition, since the cap  33  heated with sterile hot air can be cooled, even when the cap  33  is conveyed at high speed, it is possible to prevent the temperature of the cap  33  from rising due to frictional heat with the chute  59 . As a result, it is possible to increase the conveying speed of the cap  33 . 
     Further, according to the present embodiment, in the washing chamber  55 , sterile air is blown against the cap  33  by the air blow nozzle  85 , whereby a washing liquid adhering to the cap  33  is removed. As a result, most of the washing liquid such as sterile water adhering to the cap  33  is removed, so that it is possible to prevent the trouble that the cap  33  to which sterile water or the like adheres is sent to the cap attachment device  16 . 
     Further, according to the present embodiment, even after sterile air is blown from the air blow nozzle  85 , the washing liquid such as sterile water slightly remains in the cap  33 . This makes it possible to improve lubrication between the cap  33  and the chute  59  while the cap  33  is conveyed from the washing chamber  55  to the cap attachment device  16  by the chute  59  and to prevent the temperature of the cap  33  from rising due to frictional heat with the chute  59 . By suppressing the rise in the temperature of the cap  33  as described above, it is possible to stably perform seaming operation of the cap  33  in the cap attachment device  16 . In the cap attachment device  16 , sterile air may be blown against the inner surface of the cap  33  to remove washing water remaining in the cap  33 . As a result, contamination of the washing water into the bottle  30  can be minimized. 
     As described above, even when the conveying speed of the cap  33  in the cap sterilizer  50  is increased to 100 cpm or more and 1500 cpm, it is possible to reliably sterilize the cap  33  while preventing the sterilant from leaking from the housing  60 . 
     Second Embodiment 
     Next, a second embodiment of the present invention will be described below with reference to  FIG.  7   .  FIG.  7    is a schematic front view illustrating a cap sterilizer according to the second embodiment of the present invention. In the second embodiment illustrated in  FIG.  7   , the configuration of the rotation conveyance mechanism in the air rinse chamber  54  is different, and other configurations are substantially the same as those of the first embodiment described above. In  FIG.  7   , the same portions as those in the first embodiment will be assigned the same reference numerals and will not be described in detail. 
     In a cap sterilizer  50 A illustrated in  FIG.  7   , a large-sized rotation conveyance mechanism  87  larger than the rotation conveyance mechanisms  71 ,  72 , and  76  is provided in the air rinse chamber  54 . The large-sized rotation conveyance mechanism  87  rotates (on its axis) along the axis parallel to the horizontal direction, thereby directly conveying the cap  33  from the second rotation conveyance mechanism  72  to the sixth rotation conveyance mechanism  76 . Like the rotation conveyance mechanisms  71 ,  72 , and  76 , the large-sized rotation conveyance mechanism  87  may have a star wheel provided with a notch for accommodating the cap  33  and a plurality of rails arranged around the star wheel. Alternatively, the large-sized rotation conveyance mechanism  87  may be constituted by a rotary joint. 
     According to the present embodiment, the cap sterilizer  50 A can be compactly configured. Further, according to the present embodiment, in the air rinse chamber  54 , sterile hot air can be supplied while following the large-sized rotation conveyance mechanism  87  such as a rotary joint, so that even with the large-sized cap  33 , the temperature can be reliably raised. 
     Third Embodiment 
     Next, the third embodiment of the present invention will be described below with reference to  FIGS.  8  and  9   .  FIG.  8    is a schematic front view illustrating a cap sterilizer according to the third embodiment of the present invention, and  FIG.  9    is a schematic front view illustrating a modification of the cap sterilizer according to the present embodiment. The third embodiment illustrated in  FIGS.  8  and  9    is different from the first embodiment in that the cap  33  is mainly conveyed by a chute  88 . In  FIGS.  8  and  9   , the same portions as those in the first embodiment will be assigned the same reference numerals and will not be described in detail. 
     As illustrated in  FIG.  8   , a cap sterilizer  50 B includes a first infeed chamber  51 , a second infeed chamber  52 , a sterilant atomizing chamber  53 , an air rinse chamber  54 , and a washing chamber  55  provided from the upper side to the lower side. The chambers  51 ,  52 ,  53 ,  54 , and  55  are arranged inside a cylindrical body  89 . 
     In the chambers  51 ,  52 ,  53 ,  54 , and  55 , the chute  88  for conveying a plurality of the caps  33  in a row is provided. The chute  88  may include, for example, a plurality of rails. In this case, a space is formed in a region surrounded by the plurality of rails so that the cap  33  does not come off, and the cap  33  is accommodated in this space and conveyed. Although the chute  88  extends substantially linearly in  FIG.  8   , the present invention is not limited thereto, and the chute  88  may extend in a spiral shape. 
     The first infeed chamber  51  and the second infeed chamber  52  are separated by a partition wall  61 , and the second infeed chamber  52  and the sterilant atomizing chamber  53  are separated by a partition wall  62 . In addition, the sterilant atomizing chamber  53  and the air rinse chamber  54  are separated by a partition wall  64 , and the air rinse chamber  54  and the washing chamber  55  are separated by a partition wall  65 . A partition wall  91  is provided downstream of the washing chamber  55  (on the cap attachment device  16  side). 
     The cap  33  from the cap inspection machine  58  is introduced into the first infeed chamber  51 . The cap  33  from the first infeed chamber  51  is fed to the second infeed chamber  52 . Sterile hot air from a first hot air supplier  79  is sent into the second infeed chamber  52 . 
     The sterilant atomizing chamber  53  sprays a sterilant against the cap  33  fed from the second infeed chamber  52 . In the second infeed chamber  52 , the sterilant is sprayed against the cap  33  while the cap  33  is conveyed by the chute  88 . The air rinse chamber  54  air-rinses the cap  33  sprayed with the sterilant in the sterilant atomizing chamber  53 . The cap  33  is conveyed by the chute  88  in the air rinse chamber  54 , and meanwhile, sterile hot air is blown against the inner and outer surfaces of the cap  33 . As illustrated in  FIG.  9   , an elongated cover  83  covering surroundings of spray nozzles  81 A and  81 B may be provided in the sterilant atomizing chamber  53 . 
     The washing chamber  55  washes the cap  33  which has been air-rinsed in the air rinse chamber  54 . In the washing chamber  55 , the cap  33  is first blown with sterile water by a washing nozzle  84  and then blown with sterile air by an air blow nozzle  85  to remove the sterile water. The washing chamber  55  may not be provided. 
     The cap  33  carried from the washing chamber  55  is sent to the cap attachment device  16  by the chute  88 . 
     According to the present embodiment, the cap  33  can be sterilized by modifying an existing facility (such as the chute  88 ), so that it is possible to efficiently use the existing facility. 
     Fourth Embodiment 
     Next, the fourth embodiment of the present invention will be described below with reference to  FIGS.  10  and  11   .  FIG.  10    is a schematic front view illustrating a cap sterilizer according to the fourth embodiment of the present invention, and  FIG.  11    is a schematic front view illustrating a modification of the cap sterilizer according to the present embodiment. The fourth embodiment illustrated in  FIGS.  10  and  11    is different from the first embodiment in that the cap  33  is sterilized using a sorter  57 . In  FIGS.  10  and  11   , the same portions as those in the first embodiment will be assigned the same reference numerals and will not be described in detail. 
     As illustrated in  FIG.  10   , a cap sterilizer  50 C is provided in the sorter  57 . The cap sterilizer  50 C includes a first infeed chamber  51 , a second infeed chamber  52 , a sterilant atomizing chamber  53 , and an air rinse chamber  54  provided from the lower side to the upper side. 
     In the chambers  51 ,  52 ,  53 , and  54 , a conveyor  92  for conveying a plurality of the caps  33  from the lower side to the upper side is provided. The conveyor  92  is, for example, of an endless type, and conveys the cap  33  from a hopper  56  to a chute  59  via the sorter  57  while circulating vertically. The chute  59  is provided with the washing chamber  55 , and a drainage pipe  67  is connected to the washing chamber  55 . The washing chamber  55  is not necessarily provided. 
     The cap  33  from the hopper  56  is introduced into the first infeed chamber  51 . The cap  33  from the first infeed chamber  51  is fed to the second infeed chamber  52 . Sterile hot air from a first hot air supplier  79  is sent into the second infeed chamber  52 . 
     The sterilant atomizing chamber  53  sprays a sterilant against the cap  33  fed from the second infeed chamber  52 . In the second infeed chamber  52 , the sterilant is sprayed against the cap  33  which is being raised by the conveyor  92 . The air rinse chamber  54  air-rinses the cap  33  sprayed with the sterilant in the sterilant atomizing chamber  53 . The cap  33  is conveyed by the conveyor  92  in the air rinse chamber  54 , and meanwhile, sterile hot air is blown against the inner and outer surfaces of the cap  33 . As illustrated in  FIG.  11   , a rectangular cover  83  covering surroundings of spray nozzles  81 A and  81 B may be provided in the sterilant atomizing chamber  53 . 
     The cap  33  carried from the air rinse chamber  54  is sent to the cap attachment device  16  by the chute  59  via the washing chamber  55 . 
     The washing chamber  55  washes the cap  33  which has been air-rinsed in the air rinse chamber  54 . In the washing chamber  55 , the cap  33  is first blown with sterile water by a washing nozzle  84  and then blown with sterile air by an air blow nozzle  85  to remove the sterile water. 
     According to the present embodiment, the cap sterilizer  50 C can be compactly configured. In the present embodiment, the chamber is not necessarily provided. 
     Fifth Embodiment 
     Next, a fifth embodiment of the present invention will be described below with reference to  FIGS.  12  to  14   .  FIGS.  12  to  14    illustrate the fifth embodiment of the present invention. In FIGS.  12  to  14 , the same portions as those in the first to fourth embodiments will be assigned the same reference numerals and will not be described in detail. 
     (Content Filling System) 
     First, a content filling system (sterile filling system, aseptic filling system) according to the present embodiment will be described with reference to  FIG.  12   . 
     A content filling system  10 A illustrated in  FIG.  12    is a system for filling a bottle (container)  30  with a content such as a beverage. The configuration of the bottle  30  is substantially the same as that of the first to fourth embodiments. 
     As illustrated in  FIG.  12   , the content filling system  10 A includes a bottle feeding portion  21 , a sterilizer (bottle sterilizer)  11 , an air rinse device  14 , a sterile water rinse device  15 , a filling device (filler)  20 , a cap attachment device (a capper, a seamer, and a capping machine)  16 , and a product bottle conveyor  22 . These bottle feeding portion  21 , sterilizer  11 , air rinse device  14 , sterile water rinse device  15 , filling device  20 , cap attachment device  16 , and product bottle conveyor  22  are disposed in this order along a conveying direction of the bottle  30  from an upstream side to a downstream side. Between the sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , and the cap attachment device  16 , a plurality of convey wheels  12  for conveying the bottle  30  between these devices is provided. 
     The configurations of the bottle feeding portion  21 , the sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , the cap attachment device  16 , and the product bottle conveyor  22  are substantially similar to the configurations in the first to fourth embodiments. 
     The cap  33  is sterilized by the cap sterilizer  50 D in advance. The cap sterilizer  50 D is disposed inside a sterile chamber  13  (to be described later) and near the cap attachment device  16 , for example. In the cap sterilizer  50 D, the caps  33  carried in from the outside of the sterile chamber  13  are sequentially conveyed toward the cap attachment device  16 . Mist or gas of hydrogen peroxide is blown against inner and outer surfaces of the cap  33  on the way of conveyance of the cap  33  toward the cap attachment device  16  and then the cap  33  is dried with hot air and sterilized. The configuration of the cap sterilizer  50 D thus configured will be described later. 
     The sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , the cap attachment device  16 , and the cap sterilizer  50 D each have a wheel. The sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , the cap attachment device  16 , and the cap sterilizer  50 D are connected to each other by the wheels (a conveyance wheel  12 , each wheel of the sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , and the cap attachment device  16 , and a sterilant atomizing wheel  41  and an air rinse wheel  42  of the cap sterilizer  50 D). 
     In addition, the content filling system  10 A includes the sterile chamber  13 . The sterile chamber  13  houses the sterilizer  11 , the air rinse device  14 , the sterile water rinse device  15 , the filling device  20 , the cap attachment device  16 , and the cap sterilizer  50 D which have been described above. This content filling system  10 A may be, for example, a sterile filling system. In this case, the interior of the sterile chamber  13  is kept in a sterile state. 
     In addition, the sterile chamber  13  is partitioned into a bottle sterile chamber  13   a  and a filling/seaming chamber  13   b . A chamber wall  13   c  is provided between the bottle sterile chamber  13   a  and the filling/seaming chamber  13   b , and the bottle sterile chamber  13   a  and the filling/seaming chamber  13   b  are adjacent to each other with the chamber wall  13   c  interposed therebetween. In the bottle sterile chamber  13   a , the sterilizer  11 , the air rinse device  14 , and the sterile water rinse device  15  are arranged. In the filling/seaming chamber  13   b , the filling device  20 , the cap attachment device  16 , and the cap sterilizer  50 D are arranged. In this embodiment, although the chamber wall  13   c  is provided between the bottle sterile chamber  13   a , the filling/seaming chamber  13   b  and a cap sterilization chamber  47  (described later), a chamber wall may be provided for each wheel. 
     Alternatively, the content filling system  10 A may be a high temperature filling system that fills a content at a high temperature of 85° C. or more and less than 100° C. The content filling system  10  may also be a medium temperature filling system that fills a content at a medium temperature of 55° C. or more and less than 85° C. 
     (Cap Sterilizer) 
     Next, with reference to  FIGS.  12  to  14   , the configuration of the cap sterilizer  50 D described above and a mechanism used to convey the cap  33  to the cap sterilizer  50 D will be described. 
     As illustrated in  FIG.  12   , the cap sterilizer  50 D includes the sterilant atomizing wheel  41  and the air rinse wheel  42 . The sterilant atomizing wheel  41  and the air rinse wheel  42  are arranged in this order along the conveying direction of the cap  33 . In  FIG.  12   , the sterilant atomizing wheel  41  and the air rinse wheel  42  are each constituted by one wheel, but the present invention is not limited thereto, and the sterilant atomizing wheel  41  and/or the air rinse wheel  42  may include a plurality of wheels. 
     A hopper  56 , a sorter  57 , and a cap inspection machine  58  are provided on the previous process side of the sterilant atomizing wheel  41  and outside the sterile chamber  13 . A large number of the caps  33  are randomly charged into the hopper  56  from the outside. The sorter  57  arranges the caps  33 , randomly charged into the hopper  56 , in one row or multiple rows and conveys the caps  33  from a lower side to an upper side in the vertical direction. The cap inspection machine  58  inspects the shape and the like of each of the caps  33  and discharges the caps  33  failed in inspection. The caps  33  which have passed the inspection are conveyed in a row toward the cap sterilizer  50 D disposed inside the sterile chamber  13 . 
     The cap  33  is a well-known one and has a substantially circular planar shape with an opening on the inner surface side. As the cap  33 , one formed of a thermoplastic resin such as high density polyethylene (HDPE), polypropylene (PP), and biodegradable plastic can be used. As the cap  33 , in addition to a normal bottle cap, a composite cap or a sport cap may be used. 
     Between the cap inspection machine  58  and the cap sterilizer  50 D, a conveyance guide  70  for conveying a plurality of the caps  33  in a row is provided. The conveyance guide  70  may include, for example, a plurality of rails. In this case, a space is formed in a region surrounded by the plurality of rails so that the cap  33  does not come off, and the cap  33  is accommodated in this space and conveyed. The cap  33  is transferred from the cap inspection machine  58  side toward the cap sterilizer  50 D by its own weight. By providing the conveyance guide  70  thus configured, it is possible to convey the cap  33  at high speed from the cap inspection machine  58  to the cap sterilizer  50 D. The conveyance guide  70  is provided with an openable and closable stopper  49 . When the stopper  49  is opened, the cap  33  is sent to the cap attachment device  16  via the conveyance guide  70 . On the other hand, when the stopper  49  is closed, the cap  33  stays at this position. The cap  33  may be conveyed at high speed by using compressor air or a conveyer (or a combination thereof) as the conveyance guide  70 . 
     The sterilant atomizing wheel  41  conveys the cap  33  while rotating (revolving) and at the same time sprays the sterilant against the cap  33  being conveyed. The sterilant atomizing wheel  41  is disposed adjacent to the air rinse wheel  42 . A wheel (not illustrated) which causes the sterilant to stay while adhering the sterilant between the sterilant atomizing wheel  41  and the air rinse wheel  42  may be provided without changing the order of the sterilant atomizing wheel  41  and the air rinse wheel  42 . 
     As illustrated in  FIG.  13   , the sterilant atomizing wheel  41  has a first rotating mechanism  43  which conveys the cap  33  while rotating and spray nozzles  81 A and  81 B which blow a sterilant against the cap  33  rotated and conveyed by the first rotating mechanism  43 . The first rotating mechanism  43  rotates (on its axis) along an axis parallel to the vertical direction, thereby rotating (revolving) and conveying the plurality of the caps  33 . The first rotating mechanism  43  has a star wheel  43   a  located at the center and provided with a notch for accommodating the cap  33  and a plurality of rails  43   b  arranged around the star wheel  43   a  and preventing the cap  33  from coming off. The cap  33  is conveyed as the star wheel  43   a  is driven, guided by the rail  43   b , and rotated (revolved). By using the first rotating mechanism  43  thus configured, it is possible to convey the cap  33  at high speed within the sterilant atomizing wheel  41 . 
     The sterilant supplied by the sterilant atomizing wheel  41  is, for example, hydrogen peroxide solution. The cap  33  sent from the conveyance guide  70  (see  FIG.  12   ) is delivered to the star wheel  43   a , and while the cap  33  is conveyed by the star wheel  43   a , the sterilant is sprayed by the spray nozzles  81 A and  81 B. A supply spray  95  which supplies a sterilant and a heater  96  which heats the sterilant from the supply spray  95  are provided above the first rotating mechanism  43 . A first supply pipe  97 A and a second supply pipe  97 B which branch and supply the sterilant are connected to the heater  96 . Among the supply pipes, the first supply pipe  97 A is connected to the spray nozzle  81 A for outer surface which supplies the sterilant to the outer surface (top surface portion) side of the cap  33 . On the other hand, the second supply pipe  97 B is connected to the spray nozzle  81 B for inner surface which supplies the sterilant to the inner surface (opening) side of the cap  33 . For example, a tunnel  48  having a substantially arc shape in plan view is disposed above the rail  43   b  and around the spray nozzles  81 A and  81 B. The tunnel  48  covers the surroundings of the spray nozzles  81 A and  81 B, prevents the sterilant from the spray nozzles  81 A and  81 B from scattering to the surroundings, and enables effective spraying of the sterilant to the cap  33 . 
     An adhesion amount of hydrogen peroxide necessary for sterilizing the cap  33  is 0.6 μL/cm 2  or more and 4.7 μL/cm 2  or less (preferably 1.2 μL/cm 2  or more and 2.4 μL/cm 2  or less) in terms of 35% by weight. Within this range, the cap  33  can be sterilized at high speed, and a medicine can be reliably removed by air rinsing to be described later. 
     As the sterilant, besides hydrogen peroxide, alcohols such as peracetic acid, nitric acid, chlorine sterilant, sodium hydroxide, potassium hydroxide, ethyl alcohol, and isopropyl alcohol, chlorine dioxide, ozone water, acid water, and surfactant may be used alone, or two or more of these may be used in combination at any ratio. 
     Referring to  FIG.  12   , the air rinse wheel  42  conveys the cap  33  sprayed with the sterilant in the sterilant atomizing wheel  41  while rotating (revolving) and at the same time air-rinses the cap  33  being conveyed. The air rinse wheel  42  is disposed adjacent to the cap attachment device  16 . 
     As illustrated in  FIG.  14   , the air rinse wheel  42  has a second rotating mechanism  44  which conveys the cap  33  while rotating and air rinse nozzles  94 A and  94 B which blow sterile hot air against the cap  33  rotated and conveyed by the second rotating mechanism  44 . The second rotating mechanism  44  rotates (on its axis) along the axis parallel to the vertical direction, thereby rotating (revolving) and conveying the plurality of the caps  33 . The second rotating mechanism  44  has a star wheel  44   a  located at the center and provided with a notch for accommodating the cap  33  and a plurality of rails  44   b  arranged around the star wheel  44   a  and preventing the cap  33  from coming off. The cap  33  is conveyed as the star wheel  44   a  is driven, guided by the rail  44   b , and rotated (revolved). By using the second rotating mechanism  44  thus configured, it is possible to convey the cap  33  at high speed within the air rinse wheel  42 . 
     The cap  33  is sequentially conveyed by the second rotating mechanism  44  in the air rinse wheel  42 , and meanwhile, sterile hot air is blown against the inner and outer surfaces of the cap  33 . Sterile hot air from a hot air supplier  80  located outside the sterile chamber  13  is sent to the air rinse wheel  42 . A first air supply path  98 A and a second air supply path  98 B through which sterile hot air is supplied are connected to the hot air supplier  80 . Among the air supply paths, the first air supply path  98 A is connected to the air rinse nozzle  94 A for outer surface which supplies sterile hot air to the outer surface (top surface portion) side of the cap  33 . On the other hand, the second air supply path  98 B is connected to the air rinse nozzle  94 B for inner surface which supplies sterile hot air to the inner surface (opening) side of the cap  33 . The air rinse nozzles  94 A and  94 B blow out sterile hot air supplied from the hot air supplier  80  via the air supply paths  98 A and  98 B. In addition, for example, a cover  99  having a substantially arc shape in plan view is disposed above the rail  44   b  and around the air rinse nozzles  94 A and  94 B. The cover  99  covers the surroundings of the air rinse nozzles  94 A and  94 B and prevents the sterilant blown off by sterile hot air from the air rinse nozzles  94 A and  94 B from scattering to the surroundings. The air rinse nozzles  94 A and  94 B may be fixed pipes or may blow hot air while following the cap  33  by using a rotary joint. An additional hot air nozzle may be preliminarily provided at a downstream position on the sterilant atomizing wheel  41 . In addition, in order to shorten the sterilization time of the cap  33 , a preheating wheel (not illustrated) may be provided on the upstream side of the sterilant atomizing wheel  41 . 
     The temperature of sterile hot air is, for example, 80° C. or more and 140° C. or less, preferably 90° C. or more and 120° C. or less. The air volume of sterile hot air is, for example, 5 m 3 /min or more and 20 m 3 /min or less. The sterile hot air blowing time is 0.5 seconds or more and 20 seconds or less, preferably 1 second or more and 14 seconds or less. By blowing sterile hot air against the cap  33 , the temperature of the cap  33  is raised to 40° C. or more, preferably 50° C. or more. As a result, the sterilant adhering to the cap  33  is removed. Sterile hot air may contain a trace amount of a component of a sterilant such as hydrogen peroxide. As described above, in the air rinse wheel  42 , sterile hot air is blown against the cap  33  from the air rinse nozzles  94 A and  94 B. This makes it possible to reliably remove the sterilant adhering to the cap  33  in the sterilant atomizing wheel  41 . 
     Thus, the cap  33  from which the sterilant has been removed by sterile hot air at the air rinse wheel  42  is delivered to the cap attachment device  16 . Thereafter, in the cap attachment device  16 , the cap  33  delivered from the cap sterilizer  50 D is attached to the mouth of the bottle  30 . 
     Throughout the cap sterilizer  50 D, the conveying speed of the cap  33  is 100 cpm or more and 1500 cpm or less, preferably 500 cpm or more and 1000 cpm or less. According to the cap sterilizer  50 D according to the present embodiment, even when the cap  33  is conveyed at high speed as described above, the cap  33  can be sterilized reliably. The number of the caps  33  passing through a predetermined position per minute is represented by cap per minute (cpm). When the filling speed of the bottle  30  is slow, such as when the bottle  30  is a large size bottle (having an inner capacity of 1 L or more), the conveying speed of the cap  33  may be made slower than the above speed in accordance with this filling speed. In this case, supply conditions (temperature, flow rate, etc.) of hot air in the air rinse wheel  42  may be adjusted so that the temperature of the cap  33  does not rise. 
     In the sterilant atomizing wheel  41  and the air rinse wheel  42 , since the unsterilized cap  33  (the cap  33  in the step of being sterilized) is introduced into the sterile chamber  13 , it is preferable to cover these wheels  41  and  42  (at least the sterilant atomizing wheel  41 ) with another chamber so that bacteria do not contaminate a filling/seaming area. For example, as illustrated in  FIG.  12   , the sterilant atomizing wheel  41  may be covered with the cap sterilization chamber  47 . An air supply line  47   a  and an exhaust line  47   b  are connected to the cap sterilization chamber  47 . The air supply line  47   a  and the exhaust line  47   b  communicate with the outside of the sterile chamber  13 , and clean air is supplied and exhausted between the outside and the cap sterilization chamber  47 . The internal pressure (positive pressure) of the cap sterilization chamber  47  is controlled to be lower than the internal pressure of the filling/seaming chamber  13   b . As a result, it is possible to prevent bacteria adhering to the unsterilized cap  33  (the cap  33  in the step of being sterilized) from entering the filling/seaming chamber  13   b . It is preferable that the pressure of the bottle sterile chamber  13   a  is similarly lower than the pressure of the filling/seaming chamber  13   b.    
     (Content Filling Method) 
     Next, a content filling method using the above-described content filling system  10 A ( FIG.  12   ) will be described. In the following description, a filling method at a normal time, that is, a content filling method in which a content such as a beverage is filled inside the bottle  30  to produce the product bottle  35  will be described. 
     In a manner substantially similar to the cases of the first to fourth embodiments, first, the bottle  30  sequentially passes through the bottle feeding portion  21 , the sterilizer  11 , the air rinse device  14 , and the filling device  20 , and a content is filled therein. 
     Subsequently, the bottle  30  filled with the content by the filling device  20  is conveyed to the cap attachment device  16  by the convey wheel  12 . 
     On the other hand, the cap  33  is sterilized by the cap sterilizer  50 D illustrated in  FIG.  12    in advance (cap sterilization step). Meanwhile, first, a large number of the caps  33  are randomly charged into the hopper  56  located outside the cap sterilizer  50 D. Then, the caps  33  randomly charged into the hopper  56  are aligned by the sorter  57  and then conveyed to the cap inspection machine  58 . Then, in the cap inspection machine  58 , the shape and the like of each of the caps  33  are inspected, and the caps  33  which have passed the inspection are conveyed in a row toward the cap sterilizer  50 D by the conveyance guide  70 . 
     The cap  33  introduced into the cap sterilizer  50 D is delivered to the sterilant atomizing wheel  41 . Subsequently, in the sterilant atomizing wheel  41 , while the cap  33  is rotated and conveyed by the first rotating mechanism  43 , a sterilant such as a hydrogen peroxide solution is sprayed from the spray nozzles  81 A and  81 B, and the inner and outer surfaces of the cap  33  are sterilized (sterilant spray step). 
     Subsequently, the cap  33  sprayed with the sterilant is delivered to the air rinse wheel  42 . In the air rinse wheel  42 , the cap  33  is rotated and conveyed by the second rotating mechanism  44 , and meanwhile, sterile hot air is blown against the inner and outer surfaces of the cap  33  (air-rinsing step). As a result, the sterilant adhering to the cap  33  is air-rinsed. Thereafter, the cap  33  is delivered from the air rinse wheel  42  to the cap attachment device  16 . 
     The cap  33  sterilized by the cap sterilizer  50 D as described above is attached to the mouth of the bottle  30  which has been conveyed from the filling device  20  in the cap attachment device  16 . Consequently, the product bottle  35  having the bottle  30  and the cap  33  is obtained (cap attaching step). 
     Thereafter, the product bottle  35  is conveyed from the cap attachment device  16  to the product bottle conveyor  22  and is carried toward the outside of the content filling system  10 A. 
     The respective steps from the sterilization step to the cap attachment step are performed in a sterile atmosphere surrounded by the sterile chamber  13 , that is, in a sterile environment. After the sterilization treatment, aseptic air of positive pressure is supplied into the sterile chamber  13  so that the aseptic air is always blown toward the exterior of the sterile chamber  13 . 
     The production (conveying) speed of the bottle  30  in the content filling system  10 A is preferably 100 bpm or more and 1500 bpm or less. Here, the conveying speed of the bottle  30  per minute is represented by bottle per minute (bpm). 
     As described above, according to the present embodiment, the cap sterilizer  50 D includes the sterilant atomizing wheel  41 , which conveys the cap  33  while rotating and, at the same time, sprays a sterilant against the cap  33  being conveyed, and the air rinse wheel  42  which conveys the cap  33  while rotating and, at the same time, air-rinses the cap  33  being conveyed. As a result, since conveyance of the cap  33  and sterilization and air-rinsing of the cap  33  can be continuously performed, the conveying speed of the cap  33  can be increased, and, at the same time, the cap  33  can be efficiently sterilized. 
     Further, according to the present embodiment, at the air rinse wheel  42 , sterile hot air is blown against both the inner and outer surfaces of the cap  33  by the air rinse nozzles  94 A and  94 B. 
     Thus, at the sterilant atomizing wheel  41 , the sterilant adhering to the inner and outer surfaces of the cap  33  can be reliably removed by the spray nozzles  81 A and  81 B. Accordingly, the high concentration of the sterilant can be blown against the cap  33  in the sterilant atomizing wheel  41 , and as a result, the conveying speed of the cap  33  can be increased. 
     Further, according to the present embodiment, since both the cap sterilizer  50 D and the cap attachment device  16  are disposed in the sterile chamber  13 , the entire content filling system  10 A can be compactly configured. 
     In the present embodiment, the cap sterilizer  50 D is installed on the same plane as the plane on which the filling device  20  and the cap attachment device  16  are arranged, but the present invention is not limited thereto, and the cap sterilizer  50 D may be installed above the cap attachment device  16 . 
     Modification 
     Next, a modification of the content filling system according to the fifth embodiment will be described with reference to  FIGS.  15  and  16   . In  FIGS.  15  and  16   , the same portions as those in the embodiment illustrated in  FIGS.  12  to  14    will be assigned the same reference numerals and will not be described in detail. 
       FIG.  15    is a plan view (view corresponding to  FIG.  12   ) illustrating the content filling system  10 A according to a modification (Modification 1) of the present embodiment. In  FIG.  15   , unlike the embodiment illustrated in  FIGS.  12  to  14   , the cap sterilization chamber  47  is located outside the sterile chamber  13 , and the cap sterilization chamber  47  and the sterile chamber  13  are arranged adjacent to each other. The cap  33  carried from the cap sterilization chamber  47  is conveyed to the cap attachment device  16  by a cap conveyance wheel  46 . 
       FIG.  16    is a plan view (view corresponding to  FIG.  12   ) illustrating the content filling system  10 A according to a modification (Modification 2) of the present embodiment. In  FIG.  16   , unlike Modification 1 illustrated in  FIG.  15   , a plurality of the air rinse wheels  42  is provided, and a cover  99   a  is provided to straddle the plurality of air rinse wheels  42 . The cover  99   a  meanders in plan view along the traveling direction of the cap  33 . As the cap  33  moves inside the cover  99   a , sterile hot air is blown against the cap  33 . 
     One wheel may be provided instead of the plurality of the air rinse wheels  42 , and this wheel may be provided with an upper rotary joint (not illustrated) to blow hot air against the cap  33  with an air rinse nozzle following the cap  33 . 
     It is preferable to sterilize the above-described cap sterilizers (cap conveyors/sterilizers)  50 A,  50 B,  50 C, and  50 D with hydrogen peroxide or a peracetic acid detergent before actually carrying out production using the cap  33 .