Abstract:
Provided is a sterilization device for a container which exhibits high sterilization performance while being low in cost. A heating medium is positioned in a sterilant passage so as to block the downstream end thereof in the direction in which the liquid sterilant is discharged. A ventilation passage is formed in the lateral surface of a tube body of a sterilant supply tube, on the upstream side in the direction in which the liquid sterilant is discharged in relation to the heating medium. A sterilant supply unit sterilizes the inner-peripheral surface of a container as a result of the sterilant vaporizing upon reaching the heating medium, leaking to the exterior via the ventilation passage formed in the lateral surface of the tube body, and adhering to the inner-peripheral surface of the container.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a device which supplies a sterilant into a container for beverages, and typically a PET bottle for sterilization. 
       BACKGROUND ART 
       [0002]    In a case of aseptic filling of tea, fruit juice beverages, coffee beverages, and the like, the inside and the outside of a container to be filled with such a beverage needs to be sterilized before the container is filled with the beverage. Therefore, in a method of sterilizing a molded container such as a paper container or a plastic container such as a PET bottle, an aqueous solution of peracetic acid (with a rational formula of CH 3 C(═O)OOH) or an aqueous solution of hydrogen peroxide (H 2 O 2 ) is mainly used. In addition, in a case where a container as a sterilization object has a deep bottom shape or an uneven shape, a method of sterilizing the container by spraying a sterilant toward the sterilization object and drying the container is known. In addition, a method of sterilizing a container by heating a sterilant to its boiling point or higher so as to be vaporized, spraying the vaporized sterilant into the air to be condensed which adheres to the container as fine mist, and drying the container is also known. 
         [0003]    However, in the sterilization methods according to the related art, a high concentration of hydrogen peroxide is used, and thus the sterilizing ability is sufficient. However, the hydrogen peroxide adsorbs onto and penetrates into the surface layer of the container, and it takes time for the removal of the hydrogen peroxide. Therefore, the sterilization process cannot be shortened. Here, Patent Document 1 proposes, as a method of reliably performing sterilization at a high speed, a method of introducing a mist of hydrogen peroxide condensed and generated after temporarily vaporizing droplets of hydrogen peroxide into a pre-heated PET bottle and blowing hot air into the PET bottle. 
       CITATION LIST 
     Patent Literature 
       [0004]    [Patent Document 1] Japanese Patent No. 4493592 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0005]    In the sterilization method in Patent Document 1, the droplets of hydrogen peroxide are generated by mixing an aqueous solution of hydrogen peroxide with compressed air in a two-fluid spray. Therefore, although the sterilization method of Patent Document 1 has high sterilization performance, the two-fluid spray and the compressed air are needed in order to generate the mist of hydrogen peroxide. Therefore, sterilant cost is increased and the concentration of hydrogen peroxide is reduced due to the dilution with the air. 
         [0006]    The invention has been made on the basis of the problems, and an object thereof is to provide a sterilization device for a container, which has high sterilization performance with low cost. 
       Solution to Problem 
       [0007]    A sterilization device of the invention includes a sterilant supply tube which has a sterilant passage inside the sterilant supply tube, through which a discharged sterilant in liquid form passes in a state in which the sterilant supply tube is inserted into a container as a sterilization object, a heating medium which heats and vaporizes the sterilant that passes through the sterilant passage, and a ventilation passage which allows the sterilant heated and vaporized by the heating medium to leak out of the sterilant supply tube. 
         [0008]    The sterilization device of the invention heats and vaporizes the sterilant inside the container and allows the vapor to adhere to the inner surface of the container as it is, and thus can realize high sterilization performance with low cost. 
         [0009]    The sterilization device of the invention includes at least a first embodiment and a second embodiment. 
         [0010]    In the sterilization device according to the first embodiment, the heating medium is disposed to block a downstream side in a direction in which the sterilant in the liquid form is discharged in the sterilant passage, the ventilation passage is formed in a side surface of the sterilant supply tube and is formed closer to an upstream side in the direction in which the sterilant in the liquid form is discharged than the heating medium. In the sterilization device according to the first embodiment, the sterilant that reaches the heating medium and vaporizes leaks out through the ventilation passage, to the outside that is, to the inside of the container, formed in the side surface of the sterilant supply tube. The sterilant which leaks out to the inside of the container, adheres to the inside of the container to perform sterilization. 
         [0011]    In the first embodiment, it is preferable that a plurality of ventilation passages are provided in the side surface of the sterilant supply tube in order to allow the vaporized sterilant to be reliably adhered to the inner surface of the container. 
         [0012]    In the sterilization device according to the first embodiment, in a case where a heat source which heats the heating medium is provided, it is preferable that a heat source is disposed on an opposite side of the sterilant supply tube with respect to the heating medium in an axial direction of the sterilant supply tube and has dimensions in a radial direction of the heat source that are equal to or smaller than those in a radial direction of the sterilant supply tube. When the sterilant supply tube is inserted into or removed from the container, obstacle can be prevented. 
         [0013]    In the sterilization device according to the second embodiment, the heating medium is disposed to have a predetermined length along the sterilant passage, the ventilation passage is formed at a downstream end in a direction in which the sterilant in the liquid form is discharged in the sterilant supply tube, In the sterilization device according to the second embodiment, the sterilant that is vaporized in a process of moving along the heating medium leaks out through the ventilation passage formed at the downstream end of the sterilant supply tube. 
         [0014]    In the sterilization device according to the second embodiment, the heating medium may be configured to surround the sterilant passage. 
         [0015]    In this case, since the sterilant that passes through the sterilant passage is heated from all around the periphery thereof, thus the sterilant can be efficiently vaporized. 
       Advantageous Effects of Invention 
       [0016]    The sterilization device of the invention heats and vaporizes the sterilant inside the container and allows the vapor to adhere to the inner surface of the container as it is, and thus can realize high sterilization performance with low cost. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0017]      FIG. 1  is a view illustrating a schematic configuration of an aseptic beverage filling machine in a first embodiment of the invention. 
           [0018]      FIG. 2  is a view illustrating a sterilization device for a container applied to the aseptic beverage filling machine of  FIG. 1 . 
           [0019]      FIG. 3  is a view illustrating a state before a sterilant supply tube of the sterilization device illustrated in  FIG. 2  is inserted into a container. 
           [0020]      FIGS. 4(   a ) to  4 ( c ) are partially enlarged longitudinal sectional views of the sterilant supply tube illustrated in  FIGS. 1 and 2 . 
           [0021]      FIG. 5  is a view illustrating a modification example of the sterilant supply tube in the first embodiment. 
           [0022]      FIG. 6  is a view illustrating a modification example regarding the arrangement of ventilation passages in the first embodiment. 
           [0023]      FIG. 7  is a view illustrating a sterilization device for a container in a second embodiment of the invention. 
           [0024]      FIGS. 8(   a ) to  8 ( c ) are enlarged longitudinal sectional views of a sterilant supply tube in the second embodiment of the invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
       [0025]    Hereinafter, a sterilization device for a container of the invention will be described on the basis of an embodiment applied to an aseptic beverage filling machine. 
         [0026]    As illustrated in  FIG. 1 , an aseptic beverage filling machine  1  includes, as constituent elements, an importing conveyor  10  which imports a container  100  to the aseptic beverage filling machine  1 , a sterilization device  11  which sterilizes the container  100 , a rinsing device  13  which rinses the container  100 , a filling device  14  which fills the container  100 , which is subjected to sterilization and rinsing, with a liquid (beverage), a capper  15  which attaches a cap  20  to the container  100  filled with the beverage, and an exporting conveyor  16  which exports the container  100  to the outside of the aseptic beverage filling machine  1 . Transporting star wheels  17  are provided between the constituent elements so that the container  100  can be transported between the constituent elements. 
         [0027]    The transport path of the container  100  in the sterilization device  11 , the rinsing device  13 , the filling device  14 , and the capper  15  is provided on a base support  21 . On the base support  21 , a chamber C which covers the sides and the upper side of a space on the base support  21  is provided to maintain the transport path of the container  100  in the sterilization device  11 , the rinsing device  13 , the filling device  14 , and the capper  15  in a sterile environment. 
         [0028]    In addition, in the chamber C, a shower-like or sprinkler-like spray nozzle (not illustrated) is provided to spray a sterilant, a rinsing liquid, and the like into the chamber C. 
         [0029]    In addition, a drain port (not illustrated) is formed in the base support  21  to recover the sprayed sterilant or the rinsing liquid, and the revered sterilant and the like are discharged to an external recovery unit through the drain port. 
         [0030]    A sterilant supply unit  11   a  is provided in association with the sterilization device  11 . The sterilant supply unit  11   a  supplies the sterilant to the chamber C and the sterilization device  11 . The sterilant supplied to the chamber C is used to sterilize the inside of the chamber C, and the sterilant supplied to the sterilization device  11  is used to sterilize the inside and the outside of the container  100 . This embodiment is characterized in that the inside of the container  100  is sterilized as described below. In addition, as the sterilant, for example, chemicals such as peracetic acid and hydrogen peroxide may be applied. 
         [0031]    Hereinafter, the details of the sterilization device in the aseptic beverage filling machine  1  will be described with reference to  FIGS. 2  to  FIGS. 4(   c ). 
         [0032]    The sterilization device  11  includes a sterilant supply unit  30  and a container holding unit  50 . The sterilization device  11  sterilizes the inner surface of the container  100  during a process of transporting the container  100  while holding the container  100  with the container holding unit  50  of the transporting star wheels  17 . However, the sterilization device  11  may also sterilize the container  100  in a state where the container  100  is stopped. 
         [0033]    Hereinafter, the configuration of the sterilization device  11  will be described in order of the sterilant supply unit  30  and the container holding unit  50 . 
         [0034]    The sterilant supply unit  30  includes a sterilant supply tube  31 , an elevating bar  36  which elevates the sterilant supply tube  31  while holding the sterilant supply tube  31 , and a guide rail  39  which supports the elevating bar  36  so as to be elevated. 
         [0035]    The guide rail  39  is provided on the base support  21  along the path on which the container  100  is transported. 
         [0036]    The elevating bar  36  can be elevated between an operation position illustrated in  FIG. 2  and a standby position illustrated in  FIG. 3 , and is located at the standby position until a sterilization process is performed. When the container  100  is transported to a predetermined sterilization position, the sterilant supply tube  31  is lowered by a driving source (not illustrated) so that the sterilant supply tube  31  is inserted into the container  100  from the opening formed at the upper end of the container  100 . 
         [0037]    When the sterilant supply tube  31  is inserted into the container  100 , the sterilant supply unit  30  supplies the sterilant in liquid form to the sterilant supply tube and vaporizes the sterilant in the sterilant supply tube  31 . The sterilant supply unit  30  allows the vaporized sterilant to leak toward the outside of the sterilant supply tube  31  and adhere to the inner surface of the container  100  for sterilization. This is the primary function of the sterilant supply unit  30 , and in order to exhibit this function, the sterilant supply tube  31  includes the following configuration. 
         [0038]    As illustrated in  FIGS. 4(   a ) to  4 ( c ), the sterilant supply tube  31  includes a hollow cylindrical tube body  32 , a needle  33  which is disposed inside the tube body  32  to discharge the sterilant toward a heating medium, a heating medium  34  which seals the tip of the tube body  32 , a heat source  35  which heats the heating medium  34 , and a nozzle ( FIGS. 2 and 3)  which supplies the sterilant to the needle  33 . In addition, a side on which the sterilant supply tube  31  is inserted into the container  100  is defined as the tip, and a side on which the nozzle  37  is provided is defined as a rear end. 
         [0039]    The tube body  32  is made of a metal material, and is preferably made of stainless steel due to the excellent corrosion resistance thereof. However, a material other than the metal material, for example, a ceramic material may also be used. 
         [0040]    As illustrated in  FIGS. 4(   a ) to  4 ( c ), the tube body includes ventilation passages  32   a  which penetrate through the tip side in the thickness direction and allow the vaporized sterilant to pass therethrough and leak toward the outside of the tube body  32 . In this embodiment, a plurality of ventilation passages  32   a  having the same diameter are provided at equal intervals in the axial direction and are provided at equal intervals also in the peripheral direction. In addition, the ventilation passages  32   a  are formed closer to the upstream side in a direction in which the sterilant is discharged than the heating medium  34 . 
         [0041]    The needle  33  is a hollow cylindrical member and is, similar to the tube body  32 , made of a metal material having excellent corrosion resistance. 
         [0042]    The needle  33  includes a discharge port  33   a  which is open at the tip, and the rear end there of is connected to the nozzle  37 . When the sterilant in the liquid form is supplied from the nozzle  37 , the sterilant in droplet form is discharged from the discharge port  33   a  toward the heating medium  34 . As illustrated in  FIGS. 2 and 3 , a tube  38  is connected to the nozzle  37 , and the tube  38  is connected to the sterilant supply unit  11   a  and supplies the sterilant to the nozzle  37  via, for example, a syringe pump (not illustrated). 
         [0043]    The discharge port  33   a  of the needle  33  is disposed at a predetermined interval from the heating medium  34 , and the sterilant in droplet form discharged from the discharge port  33   a  falls in the tube body  32  and reaches the surface of the heating medium  34 . This interval is arbitrary, and in consideration of the container  100  being sterilized while moving on the path along the transporting star wheels  17 , has to be a distance such that the sterilant reaches the heating medium  34  due to centrifugal force. 
         [0044]    The discharge port  33   a  of the needle  33  is positioned closer to the lower side than the rearmost ventilation passage  32   a  among the ventilation passages  32   a  provided in the axial direction. 
         [0045]    The heating medium  34  heats and vaporizes the falling sterilant. 
         [0046]    The heating medium  34  is a disk-shaped member having the same diameter as the outer diameter of the tube body  32  so as to seal the tip of the tube body  32  corresponding to the downstream end in the direction in which the sterilant is discharged, and similar to the tube body  32 , is made of a metal material having excellent corrosion resistance. The heating medium  34  is joined to the tip of the tube body  32  by appropriate means such as welding, an adhesive, or the like. 
         [0047]    The heat source  35  heats the heating medium  34 . 
         [0048]    The heat source  35  includes a heater  35   a  formed of electric heating wires wound in a spiral ring form, a core  35   b  on which the heater  35   a  is wound around the outer periphery of the core  35   b,  a holder  35   c  which supports the heater  35   a  in the axial direction, and a tube-shaped insulation sheath  35   d  which covers the heater  35   a.    
         [0049]    The heater  35   a  generates heat by being supplied with power from a power source (not illustrated), and directly heats the heating medium  34  and indirectly heats the heating medium  34  via the core  35   b.  For the electric heating wires used in the heater  35   a,  a well-known alloy primarily containing nickel and chromium, or an alloy primarily containing iron, chromium, and aluminum may be used. 
         [0050]    The core  35   b  may be formed integrally with the heating medium  34 , or may also be produced as a separate member so as to be joined to the tip side of the heating medium  34 . However, in order to transfer heat generated by the heater  35   a  to the heating medium  34 , a joining method that does not impede heat transfer from the core  35   b  to the heating medium  34  is preferably employed. 
         [0051]    The holder  35   c  is joined to the tip of the core  35   b  and holds the heater  35   a  at a predetermined position. In order to exhibit this function, the holder  35   c  has a greater diameter than that of the heater  35   a.    
         [0052]    The insulation sheath  35   d  covers the periphery of the heater  35   a  and thus functions as an insulation layer for preventing the heat generated by the heater  35   a  from directly affecting the inner surface of the container  100 . In order to further exhibit the function as the insulation layer, the insulation sheath  35   d  is preferably disposed at a distance from the heater  35   a  so that the inner peripheral surface thereof does not come into contact with the heater  35   a.    
         [0053]    The insulation sheath  35   d  may be made of the same metal material as that of the tube body  32  or a ceramic material. However, when the function as the insulation layer is emphasized, it is advantageous that a ceramic material having a lower thermal conductivity than that of the metal material is used. 
         [0054]    The heat source  35  described above is disposed on the opposite side of the tube body  32  with respect to the heating medium  34  in the axial direction of the tube body  32 . In addition, the dimensions in the radial direction of the heat source  35  are equal to or smaller than those of the tube body  32 . Therefore, the heat source  35  can be prevented from becoming an obstacle to insertion and removal of the sterilant supply tube  31  into and from the container  100 . 
         [0055]    Next, the container holding unit  50  is configured as a device called, for example, a gripper that holds the container  100 . As the gripper, a well-known device which grips and holds a neck  101  of the container  100  may be used. The grippers are provided at equal intervals on the outer periphery of the transporting star wheels  17  to transport the containers to predetermined positions while gripping the containers  100  transported during the previous processes. 
         [0056]    Hereinafter, a procedure of sterilizing the inside of the container  100  using the sterilization device  11  will be described. 
         [0057]    When the container  100  is transported to the sterilization position, the elevating bar  36  located at the standby position illustrated in  FIG. 3  is lowered to the operation position illustrated in  FIG. 2  such that the sterilant supply tube  31  is inserted into the container  100  and the sterilization process is started. At this time, power is supplied from the power source to the heater  35   a  to heat the heating medium  34  to a temperature higher than the boiling point of the sterilant. For example, in a case where peracetic acid is used as the sterilant, since the boiling point of the peracetic acid is near 107° C., the heating medium  34  is heated to a temperature higher than 107° C., for example, 120° C. to 200° C. 
         [0058]    Next, by operating the syringe pump of the sterilant supply unit  11   a,  the sterilant is discharged from the discharge port  33   a  of the needle  33  toward the heating medium  34  such that the sterilant D in droplet form is dropped in a downward direction A as illustrated in FIG.  4 ( b ). The amount of discharged sterilant is arbitrary. However, according to examination performed by the inventors, it was confirmed that a 500 ml (milliliters) PET bottle can be sufficiently sterilized by using only about 0.2 ml of an aqueous solution of peracetic acid having a concentration of 10%. 
         [0059]    The sterilant that reaches the heating medium  34  immediately becomes vapor as illustrated in  FIG. 4(   c ) because the heating medium  34  is heated to a temperature higher than the boiling point of the sterilant. The sterilant that becomes the vapor S moves upward toward the rear end of the sterilant supply tube  31  from the heating medium  34 . However, since the ventilation passages  32   a  are formed in the sterilant supply tube  31 , the sterilant that becomes vapor sequentially passes through a sterilant passage  32   b  which is the inside of the tube body  32  and the ventilation passages  32   a  and leaks out of the sterilant supply tube  31 . The sterilant that passes through the ventilation passages  32   a  then adheres to the inner surface of the container  100  and sterilizes the inner surface thereof. 
         [0060]    Sterilization performed in the above-described manner is performed on each of the containers  100 . 
         [0061]    Next, the actions and effects of the sterilant supply unit  30  of the sterilization device  11  will be described. 
         [0062]    Since the sterilant supply unit  30  performs sterilization by vaporizing the sterilant in the container  100 , necessary members starting from the sterilant supply tube  31  may have small sizes and may also be reduced in number. Therefore, the cost of the sterilization device  11  can be reduced. Moreover, each of the sterilant supply units  30  can perform sterilization by vaporizing the sterilant having a high concentration in the container  100  and thus can obtain high sterilizing ability. 
         [0063]    In addition, since the periphery of the heater  35   a  is covered with the insulation sheath  35   d,  an effect caused by heating which is necessary to vaporize the sterilant by using the sterilant supply unit  30  can be limited to the temperature limit of the container  100 , for example, a temperature of lower than 70° C. to 80° C. in case of the PET bottle. 
         [0064]    In addition, in the sterilant supply unit  30 , since the ventilation passages  32   a  are provided at a plurality of points in the axial direction and the peripheral direction of the tube body  32 , the sterilant vaporized by the heating medium  34  easily passes through the tube body  32  and can adhere to the inner surface of the container  100 . Therefore, the sterilization device  11  can obtain high sterilizing ability. 
         [0065]    In addition, in the sterilant supply unit  30 , the discharge port  33   a  of the needle  33  is positioned closer to the tip side than the rearmost ventilation passage  32   a . Therefore, the needle  33  acts as resistance against the second and first ventilation passages  32   a  from the rearmost side, and thus it can be said that the sterilant that moves upward between the ventilation passages  32   a  and the needle  33  easily passes through the ventilation passages  32   a.    
         [0066]    Furthermore, in the sterilant supply unit  30 , in a case where a plurality of droplets of the sterilant are continuously dropped into a single container  100 , the vaporization rate of the subsequent sterilant can be increased. That is, while the previously dropped sterilant is vaporized and moves upward, when the subsequent sterilant is dropped, the subsequent sterilant is heated in the process of passing through the vaporized sterilant and then reaches the heating medium  34 . Therefore, the vaporization rate of the sterilant is increased, and thus an increase in the efficiency of the sterilization process can be achieved. 
         [0067]    In the invention, the configurations employed by the first embodiment can be selected or can be appropriately changed to other configurations. 
         [0068]    For example, the inner diameter of the tube body  32  is uniform in the axial direction. However, the invention is not limited thereto. For example, as illustrated in  FIG. 5 , the inner diameter thereof may be reduced toward the rear end. In this case, a pressure loss in the vaporized sterilant is increased toward the rear end of the tube body  32 , and thus the sterilant can easily pass through the ventilation passages  32   a.  In addition, in the example of  FIG. 5 , the diameters of the ventilation passages  32   a  aligned in the axial direction are reduced toward the rear end, and thus the sterilant can easily pass through the ventilation passages  32   a  on the tip side. 
         [0069]    In addition, in the first embodiment, the ventilation passages  32   a  are aligned in the axial direction and are aligned in the peripheral direction. However, the invention is not limited thereto. For example, when the tube body  32  is deployed, as illustrated in  FIG. 6 , the ventilation passages  32   a  may also be arranged in a zigzag lattice pattern. It is assumed that the sterilant easily leaks out of the tube body  32 . 
       Second Embodiment 
       [0070]    Next, a second embodiment of the invention will be described with reference to  FIGS. 7 to 8(   c ). The second embodiment is similar to the first embodiment in that the sterilant is vaporized in the container  100  and is different therefrom in means for vaporizing the sterilant. Hereinafter, the second embodiment will be described focusing on the differences therebetween. 
         [0071]    In the second embodiment, when sterilization is performed, a sterilant supply tube  41  of a sterilant supply unit  40  is inserted into the inverted container  100  from below. When sterilization is ended, the sterilant supply tube  41  is lowered and removed from the container  100 . 
         [0072]    As illustrated in  FIGS. 7 to 8(   c ), the sterilant supply tube  41  includes a hollow cylindrical tube body  42 , a needle  43  which is disposed inside the tube body  42  to discharge the sterilant toward a heating medium  44 , and a nozzle  37  which supplies the sterilant to the needle  43 . In addition, even in the second embodiment, a side on which the sterilant supply tube  41  is inserted into the container  100  is defined as the tip, and the opposite side thereof is defined as a rear end. 
         [0073]    The tube body  42  is made of the same material as that of the tube body  32  of the first embodiment and is formed of a member which does not include the ventilation passages  32   a  and has a simple tube shape in which both ends in the axial direction are open. 
         [0074]    In addition, the needle  43  has the same configuration as that of the needle  33  of the first embodiment except for the disposition. That is, a discharge port  43   a  of the needle  43  is disposed to be surrounded by the heating medium  44 , and the sterilant D in droplet form discharged from the discharge port  43   a  passes through the inside of the heating medium  44  while moving upward inside the tube body  42 . 
         [0075]    The heating medium  44  heats and vaporizes the sterilant that moves upward. 
         [0076]    The heating medium  44  is formed of electric heating wires wound in a spiral ring form and mounted on the inside of the tube body  42  and surrounds a sterilant passage  42   b  inside the tube body  42  from the entire region thereof in the peripheral direction. The heating medium  44  is fixed to the inner peripheral surface of the tube body  42  and is thus held in the tube body  42 . A ceramic tube which acts as an insulation material may also be interposed between the heating medium  44  and the tube body  42 . 
         [0077]    When power is supplied from a power source (not illustrated) to the heating medium  44 , the heating medium  44  generates heat. The electric heating wires used in the heating medium  44  are the same as those of the first embodiment. 
         [0078]    Hereinafter, a procedure of sterilizing the inside of the container  100  using the sterilant supply unit  40  will be described. 
         [0079]    When the container  100  is transported to the sterilization position, as illustrated in  FIGS. 7 to 8(   c ), the sterilant supply tube  41  is inserted into the container  100  and the sterilization process is started. At this time, power is supplied from the power source to the heating medium  44  and thus the heating medium  44  is heated to a temperature higher than the boiling point of the sterilant. The heating temperature is the same as in the first embodiment. 
         [0080]    Next, by operating a syringe pump, as illustrated in  FIG. 8(   b ), the sterilant D in droplet form is discharged from the discharge port  43   a  of the needle  43  in an upward direction A toward the heating medium  44 . The amount of discharged sterilant may be the same as that of the first embodiment, and the sterilant is discharged at a speed such that the sterilant can reach the sterilant passage  44   a  of the heating medium  44 . 
         [0081]    Since the heating medium  44  is heated to a temperature higher than the boiling point of the sterilant, as illustrated in  FIG. 8(   c ), the sterilant that passes through a region surrounded by the heating medium  44  becomes vapor S in the process of moving upward though the sterilant passage  42   b.  The sterilant that becomes the vapor S leaks out from an opening (ventilation passage) at the rear end of the sterilant supply tube  41  positioned on the downstream side in a direction in which the sterilant is discharged, flows into the container  100 , adheres to the inner surface of the container  100 , and sterilizes the inner surface. 
         [0082]    Sterilization performed through the above-described procedure is performed on each of the containers  100 . 
         [0083]    The actions and effects of the sterilant supply unit  40  will be described. 
         [0084]    Similar to the sterilant supply unit  30 , the sterilant supply unit  40  can also obtain high sterilizing ability at low cost. 
         [0085]    In addition, in the sterilant supply unit  40 , since the periphery of the heating medium  44  is covered with the tube body  42 , an effect of heating needed to vaporize the sterilant can be suppressed to a temperature of lower than the temperature limit of the container  100 . 
         [0086]    In the sterilant supply unit  40 , the ability of the heating medium  44  to heat the sterilant can be adjusted by changing the length thereof in the axial direction or dividing the electric heating wires in the axial direction. Therefore, even when the amount of supplied sterilant is changed, by adjusting the heating ability as necessary, the sterilant can be vaporized without omissions. 
         [0087]    In addition, since the sterilant is discharged in the upward direction, even when the sterilant is discharged from the discharge port  43   a  of the needle  43  while not being vaporized, the sterilant falls thereafter. Therefore, a risk that the sterilant may adhere to the inner surface of the container  100  as droplets and remain in the beverage therein can be reduced. 
         [0088]    While the invention has been described above on the basis of the first and second embodiments, the configurations employed by the embodiments can be selected or can be appropriately changed to other configurations without departing from the spirit of the invention. 
         [0089]    For example, the configuration of the aseptic beverage filling machine  1  is merely an example, and the sterilization device of the invention can be applied to another type of aseptic beverage filling machine. 
         [0090]    In addition, the first embodiment can also be applied to the sterilization of an inverted container, or the second embodiment can also be applied to the sterilization of an upright container. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           1  aseptic beverage filling machine 
           10  importing conveyor 
           11  sterilization device 
           11   a  sterilant supply unit 
           13  rinsing device 
           14  filling device 
           15  capper 
           16  exporting conveyor 
           17  transporting star wheel 
           20  cap 
           21  base support 
           30 ,  40  sterilant supply unit 
           31 ,  41  sterilant supply tube 
           32 ,  42  tube body 
           32   a  ventilation passage 
           32   b,    42   b  sterilant passage 
           33 ,  43  needle 
           33   a,    43   a  discharge port 
           34 ,  44  heating medium 
           35  heat source 
           35   a  heater 
           35   b  core 
           35   c  holder 
           35   d  insulation sheath 
           36  elevating bar 
           37  nozzle 
           38  tube 
           39  guide rail 
           50  container holding unit 
           100  container 
         C chamber