Abstract:
An apparatus for blowing and filling a plastic container from a preform and using liquid as the blowing medium. The apparatus includes a mold encloses a preform so as to leave access to the mouth of the preform protruding from the upper surface of the mold. An injection head is provided for injecting a liquid into the preform and a liquid collecting member is provided for collecting any residual liquid present between the injection head and the neck of the blown and liquid filled container before opening the mold and/or moving the injection head away from the mold.

Description:
INCORPORATION BY REFERENCE 
     This application is based upon, and claims the benefit of priority from, corresponding European Patent Application No. 12151392.3 filed Jan. 17, 2012, the entire contents of which is incorporated herein by reference. 
     FIELD 
     The invention relates to an apparatus for blowing and filling containers from preforms. 
     BACKGROUND 
     Plastic containers such as bottles of water are manufactured and filled according to different methods including blow molding or stretch-blow molding. 
     According to one of these known methods a plastic preform is first manufactured through a molding process and then heated before being positioned inside a blowing mold. 
     The preform usually takes the form of a cylindrical tube closed at its bottom end and open at its opposite end. 
     Once the preform has been positioned within the mold only the open end of the preform is visible from above the mold. 
     A liquid injection head comprising an injection valve is brought into a sealing engagement with the upper surface of the mold around the open end of the preform. 
     The above-mentioned method makes use of a stretch rod which is downwardly engaged into the open end of the preform so as to abut against the closed bottom end thereof. The stretch rod is further actuated to be urged against the closed end, thereby resulting in stretching the preform. 
     After the stretching phase has been initiated a liquid is injected into the preform through its open end thanks to the injection head, as disclosed for instance in Applicant&#39;s patent EP 1 529 620 B1. Upon command, the injection valve is caused to be opened, thereby enabling flow of liquid therethrough and injection of liquid into the preform. This liquid injection causes expansion of the preform until coming into contact with the inner walls of the mold, thereby achieving the final shape of the bottle. 
     Once the bottle has been blown and filled with liquid, the injection valve is caused to be closed. 
     The Applicant has noticed that a certain amount of liquid (residual liquid) is still present in the space located between the closed injection valve and the bottle. 
     When the injection head is lifted up and/or the mold is opened to remove the blown and filled bottle residual liquid that has accumulated within the above-mentioned space splashes all around and, therefore, is wasted. 
     Also, liquid spreads all over the inner walls of the mold. 
     Liquid drops which are present on the mold inner walls have to be removed before accommodating a new preform inside the mold. Otherwise, the presence of liquid drops may impair defects in the outside surface of the next blown and filled container. 
     It is to be noted that the above situation also arises with other blow-molding methods and for other kinds of containers. 
     There is therefore a need for an apparatus remedying at least one of the above-mentioned drawbacks. 
     SUMMARY 
     In this respect, the invention is an apparatus for blowing and filling a plastic container from a preform and using a liquid as the blowing medium. The apparatus includes a liquid collecting member for collecting residual liquid that is present between the injection head and the neck of the blown and liquid filled container. 
     The residual liquid is the liquid overflow that remains around the neck of the container after it has been filled with liquid. 
     The invention makes provision for liquid collecting means which are suitable for collecting the residual liquid before opening the mold and/or raising the injection head. These means may be integrated into the apparatus. 
     According to a possible feature, the liquid collecting means are provided at least partially in the injection head and/or the mold. 
     Thus, the liquid collecting means may be integrated in whole or in part in the injection head or in the mold. 
     Alternatively, the liquid collecting means may be integrated in both the injection head and the mold so as to increase the efficiency of the liquid collecting operation. 
     According to a possible feature, the liquid collecting means comprise at least one collecting channel that is operable to be in communication with said residual liquid. 
     Such means are efficient by virtue of their simple conception. 
     According to possible feature, the liquid collecting means comprise a plurality of collecting channels that are operable to be in communication with said residual liquid. 
     According to the needs and/or the arrangement of the apparatus, a plurality of collecting channels may be envisaged rather than a single collecting channel. 
     It is to be noted that integrating the liquid collecting means in the injection head and/or the mold provides the advantage of having a compact apparatus with a reduced bulkiness. 
     For instance, the at least one collecting channel is a sucking channel. 
     Thus, the liquid is sucked in through the at least one sucking channel, e.g. thanks to a pump device located upstream said channel. 
     Alternatively, the liquid may be collected within the at least one collecting channel by gravity, which therefore does not necessitate using any sucking means. In this embodiment the at least one collecting channel is integrated in part in the mold and in the injection head. 
     According to another possible feature, the collecting channels are spatially arranged around the space that is located between the injection head and the neck of the blown and liquid-filled container. 
     Such an arrangement proves to be easy and quite efficient for getting access to the zone where the residual liquid to be collected is present. 
     According to another possible feature, the at least one collecting channel is inclined relative to a longitudinal axis passing by the centre of the neck of the blown and liquid-filled container. 
     The inclination of the at least one collecting channel is particularly useful when collecting the residual liquid through gravity. 
     According to a possible feature, the at least one collecting channel has two opposite ends of which one is in communication with the space that is located between the injection head and the neck of the blown and the liquid-filled container. 
     The possible inclination of the at least one collecting channel makes it easier to locate the communicating end of said channel in the lower part of the space that surrounds the neck of the container. 
     This advantage is obtained with liquid collecting channels provided in the injection head and/or the mold of the apparatus. 
     According to a possible feature, the liquid collecting means comprise at least one valve device that is able to prevent the residual liquid from being evacuated through said at least one collecting channel when in a closed position. 
     In an open position of said at least one valve device the residual liquid may be circulated through said at least one collecting channel either by sucking or gravity. 
     The at least one value valve device may be connected to the at least one collecting channel. 
     Said at least one valve device is located at the end of the channel which is opposite the end that is in communication with the space where the residual liquid is present. 
     According to a further possible feature, the at least one valve device is by default in a closed position that prevents liquid from being collected through said at least one collecting channel. 
     The role of the at least one closed valve device is to avoid any flow of liquid through the channel, for instance, when the liquid injection phase is operated and liquid collecting is not operated. 
     According to a possible feature, the number of collecting channels and/or their possible inclination relative to a longitudinal axis passing by the centre of the neck of the blown and liquid filled container and are adapted to the volume of the residual liquid to be collected. 
     In other words, the volume of the residual liquid to be collected depends on the space between the injection head and the neck of the container. 
     According to a possible feature, the injection head comprises a longitudinal body accommodating in a housing thereof an injection valve, the longitudinal body extending longitudinally beyond said housing through a body extension that surrounds an inner cavity facing the injection valve, the inner cavity accommodating the protruding neck of the container and the body extension comprising the at least one collecting channel. 
     The arrangement of the liquid collecting means within the body extension proves to be simple and efficient. 
     According to a possible feature, the end of the at least one collecting channel that is in communication with the space between the injection head and the neck of the container is in a lower position than the opposite end of said at least one collecting channel. Alternatively, the end communicating with the space is substantially at the same level as the opposite end. 
     Thus, the end of the at least one collecting channel in communication with the space where the residual liquid is present may be located at the basis or in the lower part of the space so as to increase the efficiency of the liquid collecting operation. 
     This feature is suitable for an embodiment where the liquid collecting means are provided in the injection head. 
     According to a possible feature, the at least one collecting channel is provided in part in the mold and in the injection head. 
     According to a possible feature, the at least one collecting channel has two parts one of which is provided in the mold and the other part in the injection head, said at least one collecting channel having an end that opens into the space located between the injection head and the neck of the blown and liquid-filled container. 
     Thus the part of the at least one collecting channel that is integrated within the injection head has the opening end. 
     According to a possible feature, the opening end of the at least one collecting channel is in an upper position than the opposite end of said at least one channel when the latter is partly provided in the mold and in the injection head. 
     This inclination makes it possible to favor the collection of liquid through the at least one collecting channel. 
     This arrangement is of particular interest when liquid collecting is to be carried out through gravity only. 
     According to a possible feature, the neck of the container has a neck ring at the basis thereof and the injection head is in a sealing engagement with the neck ring. 
     According to a possible feature, the opening end of the at least one collecting channel opens into a region of the injection head that is located close to the basis of the neck. 
     Such an arrangement makes it possible to locate the end of the at least one collecting channel as close as possible to the lower part of the space where the residual liquid is present. This arrangement enhances efficiency of the liquid collecting operation. 
     According to a possible feature, the mold comprises two halves, said at least one collecting channel being partially provided in at least one of the two mold halves. 
     For an increased efficiency, a plurality of collecting channels may be distributed into the two mold halves so as to more completely surround the above space with the residual liquid. 
     According to a possible feature, the apparatus comprises means for recycling the residual liquid that has been collected. 
     Thus, it is possible to recycle the collected liquid and, therefore, reduce or avoid waste of liquid in the process of blowing and liquid filling containers. 
     According to a possible feature, the apparatus comprises compressed air injection means for injecting compressed air into the space between the injection head and the neck of the blown and liquid filled container. 
     Such means are suitable, when activated, for cooperating with the liquid collecting means and help to collect the residual liquid that is present within the space around the container neck. 
     Thus, the efficiency of the liquid collecting operation is enhanced. 
     Additional features and advantages are described herein, and will be apparent from the following Detailed Description and the figures. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying figures in which: 
         FIG. 1  is a schematic and partial view of an apparatus for blowing and filling a container according to a first embodiment; 
         FIG. 2  is schematic view of a liquid circuit system in connection with the injection head of  FIG. 1  apparatus; 
         FIG. 3  is a schematic and partial view of an apparatus for blowing and filling a container according to a second embodiment. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a schematic and partial view illustrating the main components of an apparatus  10  for blowing and filling a container according to a first embodiment. 
     The apparatus  10  comprises a mold  12  enclosing a container  14  such as a bottle. Mold  12  comprises two mold halves  12   a  and  12   b  that are operable to move apart in order to extract container  14 . The mold may comprise more than two parts and for instance a base on which rests the container. 
     A bottle which has been manufactured through blow molding or stretch-blow molding comprises a dispensing opening  16  having a neck  18  with an outside thread and a flange or neck ring  20  that is provided at the basis of the neck. 
     As represented in  FIG. 1 , a longitudinal axis A which here coincides with the vertical axis, passes by the centre of dispensing opening  16 . 
     It is to be noted that axis A is a symmetry axis to container  14 . 
     The container has been shaped so that the dispensing opening  16  protrudes from the upper surface  12   c  of mold  12  above the latter. 
     In particular, neck ring  20  rests against a peripheral inner shoulder  22  provided at the upper part of the mold around the container  14 . 
     Apparatus  10  also comprises an injection head  24  which comes into sealing engagement (liquid-tight engagement) with the upper surface  12   c  of mold  12  before the beginning of the blowing and filling method and, in the course of operation thereof. Injection head  24  is also in a sealing engagement with container  14 , more particularly with neck ring  20 . 
     Injection head  24  comprises a longitudinal body  25  and an injection valve  26  provided in an inner housing  28  of said longitudinal body. 
     Injection head  24  is substantially cylindrical in shape as partially illustrated in  FIG. 1  and inner housing  28  is also cylindrical in shape and both are coaxial. 
     Injection head  24  and mold  12  are substantially aligned along longitudinal axis A. 
     As represented in  FIG. 1 , body  25  further extends longitudinally along longitudinal axis A through a longitudinal body  30  that extends beyond housing  28  and injection valve  26 . 
     Body extension  30  is substantially annular in shape and, for example, takes the form of a cylindrically-shaped extending wall with a frusto-conical shape on part of its outside surface. 
     Body extension  30  surrounds an inner cavity  32  which faces housing  28  and injection valve  26 . Inner cavity  32  accommodates the protruding neck  18  of container  14  which is engaged thereinto. 
     Body extension  30  has a free end  30   a  which comprises a sealing or liquid-tight end surface, perpendicular to axis A and which is in sealing engagement with upper surface  12   c  and neck ring  20 . 
       FIG. 1  apparatus  10  also includes liquid collecting means for collecting the residual liquid that is present inside cavity  32 , after blowing and liquid filling of container  14  as will be explained subsequently. 
     In the present embodiment liquid collecting means are provided in injection head  24 . 
     Liquid collecting means comprise a plurality of liquid collecting channels two of which,  34  and  36 , are represented in  FIG. 1 . 
     These channels are spatially arranged, e.g. regularly, around inner cavity or space  32  and, more particularly, are integrated into body extension  30 . 
     As represented in  FIG. 1 , each channel has two opposite ends  34   a  and  34   b ,  36   a  and  36   b . A first end  34   a ,  36   a  opens into inner cavity  32  so as to be in communication therewith while the opposite second end  34   b ,  36   b  opens onto the outside surface of body  25 . 
     Each channel is inclined relative to longitudinal axis A so that the first end  34   a ,  36   a  is in a lower position than the opposite second end  34   b ,  36   b.    
     The apparatus further comprises valve devices  38 ,  40  that are located facing the opposite ends  34   b ,  36   b  respectively and connected thereto. 
     These valve devices which are for example in a corresponding number with the collecting channels are by default in a closed state which prevents any flow of liquid therethrough. 
     Arranging the valve devices outside the injection head does not question the conception thereof and proves to be easy and cheap to implement. 
     As represented in  FIGS. 1 and 2 , apparatus  10  comprises pipes or ducts  42 ,  44  that respectively connect each channel  34 ,  36  to a pump device  46 . Pump device  46  is, in turn, connected through a connecting duct or pipe  48  to a tank or reservoir of liquid  50  that will be used for supplying liquid during the next liquid injection phase. It is to be noted that pipes or ducts  42  and  44  are part of liquid collecting means. 
     Alternatively, the members  38  and  40  which are connected to the collecting channels may be connectors and the valve devices (not represented in the drawing) may be located upstream said connectors on the respective pipes or ducts  42 ,  44 . 
     It is to be noted that the number of collecting channels may vary and, for example, be greater than two or even equal to one. 
     Also, the angle of inclination of the channels may vary as well as their shape. 
     Typically, the number of channels and their inclination depend on the volume of liquid to be collected. This amount of liquid may be assessed based on the volume of the space surrounding the container neck  18  within cavity  32 . 
     The inclination of the channel(s) relative to a plane that is perpendicular to axis A may be relatively small or even null provided that: 
     the opening end ( 34   a ,  36   a ) is located in the lower part of cavity  32  (close to neck ring  20 ), 
     the space around the opposite end ( 34   b ,  36   b ) is sufficient for arranging a valve device or a connector in contact with said opposite end. 
     For example, a channel may have a substantially cylindrical hollow shape. 
     In the present embodiment two to six channels for example four channels, are arranged within body extension  30  around cavity  32 . Each channel has an inner diameter lying between 2 and 8 mm and, for example, being equal to 4 mm. 
     The angle of inclination of each channel relative to an horizontal plane lies between 5 and 60°. 
     In order to reduce the bulkiness of the channel arrangement within the injection head the angle of inclination may preferably be between 5 and 30°. 
     This second range of inclination angles also makes the liquid collecting easier. 
     Alternatively, other shapes of channels may be envisaged. 
     For example, a single channel may be provided around the whole circumference of body extension  30  (viewed in a transverse cross-section that is perpendicular to  FIG. 1  plane) with the same longitudinal cross-section as that of  FIG. 1  or with another cross-sectional shape. Thus, the single channel may have an overall frusto-conical shape. Alternatively, angularly extended and separated portions of channels may be spatially arranged around the circumference of body extension  30 . 
     In this embodiment container  14  is a plastic container which has been manufactured according to a known method such as disclosed in Applicant&#39;s patent EP 1 529 620 B1. 
     According to this method, a plastic preform is first manufactured through a molding process and then heated before being positioned within mold  12 . 
     The preform usually assumes the shape of a cylindrical tube closed at its bottom end and open at its opposite end. 
     Once the preform has been positioned within the mold only the open end of preform is visible from above the mold. The open end is engaged within cavity  32 . 
     The open end is shaped during the process, thereby leading to dispensing opening  16 . 
     The blowing and filling process makes use of a stretch rod (this rod is not represented in the drawing but traverses the injection valve  26 ) which is downwardly engaged into the open end of the preform so as to come into contact with the closed bottom end thereof. The stretch rod is then further actuated to push the closed end downwardly and stretch the preform accordingly in a controlled manner. 
     After the stretching phase has been initiated the liquid mentioned above (e.g. water) is injected into the preform through its open end around the stretch rod, while the latter is still being actuated. For liquid injection purpose injection valve  26  is placed in an upper position away from the inner surface  28   a  so as to enable flow of liquid between valve  26  and surface  28   a . Valve devices  38  and  40  are closed. 
     This liquid injection causes expansion of the preform together with the movement of the stretch rod until coming into contact with the inner walls of the mold. 
     The final shape of the container is thus achieved. 
     Once container  14  has been blown and filled with liquid, injection valve  26  is commanded to be lowered against inner surface  28   a  (position of  FIG. 1 ) in a sealing engagement therewith, so as to prevent any further flow of liquid into container  14  and ensure liquid-tight sealing. 
     The inner cavity  32  contains residual liquid that is located around neck  18  and represents an overflow that has not been injected into container  14  following the liquid injection phase. When the channels are inclined, the residual liquid remains within cavity  32  and does not fill the channels. 
     In order to avoid such a liquid overflow to be wasted when moving the injection head away from the mold and opening the latter the liquid collecting channels act as sucking channels. Valve devices  38  and  40  are commanded to be opened and pump device  46  is commanded to operate and causes, by depression, the liquid overflow (residual liquid) to rise up inside sucking channels and pipes  42  and  44 . 
     The overflow extracted in this way is then supplied to tank  50 . The recovered or collected liquid overflow is then stored within a view to being recycled in the course of the next liquid injection phase. 
     As schematically illustrated in dotted lines in  FIG. 1 , optional means for injecting compressed air within cavity  32  are provided. When being activated such injected compressed air pushes the residual liquid into the collecting channels (when liquid collecting is operated) and, therefore, contribute to collecting the residual liquid. This contributes to increasing the efficiency of the liquid collecting operation and reducing the cycle time of the process. 
     These injection means may cooperate with liquid collecting channels which operate under the action of a sucking device, e.g. a pump device. 
     Alternatively, these injection means may be used when the liquid collecting channels are less, or even not, inclined relative to an horizontal plane and no sucking device is used. The only power used for evacuating the residual liquid through the collecting channels is that supplied by the compressed air emerging into the cavity  32  and expelling the liquid into said channels. 
     It is to be noted that the injection means may take the form of channels such as channels  52  and  54  which bring compressed air down to cavity  32  from a source of compressed air that is not represented in the drawing for the sake of clarity. 
     These channels may be inclined relative to axis A and, e.g. have the same inclination or same arrangement with no inclination as that of channels  34  and  36  for easiness of manufacturing. 
     The outlet end of each channel may be located at any place along the height of cavity  32 . 
       FIG. 3  illustrates a second embodiment of an apparatus for blowing and liquid filling containers. 
     As represented in  FIG. 3 , an apparatus  60  for blowing and filling a container  14  comprises a mold  62  and an injection head  64 . 
     Injection head  64  is almost the same as injection head  24  except that it does not contain collecting channels  34  and  36  and their associated components (valve devices, pipes, etc.). 
     Mold  62  is almost identical to mold  12  in that it comprises two mold halves  62   a  and  62   b  enclosing container  14 . 
     Neck  18  of container  14  protrudes from the upper surface  62   c  of the mold and penetrates into inner cavity  32  of injection head  64 . 
     The free end  30   a  of injection head  64  is in sealing engagement with upper surface  62   c  and neck ring  20 . 
     As represented in  FIG. 3 , the apparatus comprises liquid collecting means which are provided both in mold  62  and injection head  64 . 
     More particularly, liquid collecting means comprise a plurality of inclined liquid collecting channels two of which,  66  and  68 , are represented in  FIG. 3 . 
     The plurality of channels are integrated into the two mold halves and the injection head. For example, they are arranged with a regular spatial spacing viewed in a transverse cross-section relative to axis A. 
     Each channel has two channel parts which are aligned with each other, one channel part being provided in one mold half and the other channel part in the injection head. 
     Thus, channel  66  (resp.  68 ) comprises a first part  66   a  (resp.  68   a ) integrated within mold half  62   a  (resp.  62   b ) and a second part  66   b  (resp.  68   b ) integrated within body extension  30 . 
     Liquid-tight means are provided around the joint surface between the two channel parts  66   a ,  66   b  (resp.  68   a ,  68   b ) in order to prevent any leak of liquid. For instance, a toroidal gasket seal  67 ,  69  is arranged in the injection head around the joint surface of channel  66 ,  68  respectively. 
     Each channel  66 ,  68  has two opposite ends  66   c  and  66   d ,  68   c  and  68   d.    
     One of the two opposite ends  66   c ,  68   c  (inlet) is in an upper position than the opposite end  66   d ,  68   d  (outlet) and emerges into the upper surface  62   c  of the mold. 
     As represented in  FIG. 3 , the emerging end  66   c ,  68   c  of each collecting channel is located in the region of the cavity  32  that surrounds the neck  18  and, more particularly, in the lower part thereof. 
     As shown in  FIG. 3 , the emerging ends are located at the basis of the neck  18  and above the neck ring  20 . 
     Neck ring  20  rests against a peripheral inner shoulder  70  provided at the upper part of the mold around container  14 . 
     As for  FIG. 1  collecting channels  34  and  36 , collecting channels  66  and  68  are inclined relative to longitudinal axis A. 
     As for the  FIG. 1  embodiment, the number of collecting channels, their angle of inclination as well as their shape may vary depending on the amount of residual liquid present within inner cavity  32 . The same remarks as those provided above relative to the first embodiment also apply here and will not be repeated. 
     In  FIG. 3  embodiment two to six channels, for example four channels, may be distributed all around cavity  32  both in the mold halves and body extension  30 . 
     Each channel has an inner diameter which lies between 4 and 8 mm and, for example, is equal to 6 mm. This range of values is greater than that of  FIG. 1  embodiment so as to be more adapted when gravity liquid collecting is used. However, if compressed air is injected into cavity  32  the inner diameter of the channels may be the same as for  FIG. 1  channels. 
     Furthermore, the angle of inclination of each two-part channel is smaller than that of the  FIG. 1  channels in order to avoid any interference between the part of the channel located in the mold half and the shape of the container (profile of the inner walls of each mold half). 
     Thus, the angle of inclination of each two-part channel relative to an horizontal plane lies between 5 and 45° and, for instance, is equal to 30°. 
     The apparatus further comprises valve devices  72 ,  74  which are respectively located facing outlets  66 b,  68 b of collecting channels  66  and  68  and are connected thereto. These valve devices are closed by default. 
     Ducts or pipes  76 ,  78  are respectively connected to valve devices  72  and  74  at one end and to pump device  46  of  FIG. 2  at the opposite end. 
     The same remarks as those made in relation to valve devices  38  and  40  in  FIG. 1  apply here and will not be repeated. 
     The liquid collecting and recycling means represented in  FIG. 2  (liquid circuit system) may also be used in conjunction with  FIG. 3  embodiment. 
     Once container  14  has been blown and liquid-filled, injection valve  26  is commanded to be lowered against inner surface  28   a  (position of  FIG. 3 ), in a sealing engagement therewith so as to prevent any further flow of liquid into container  14  and ensure liquid-tight sealing. 
     The residual liquid or liquid overflow that is located within cavity  32  around neck  18  following the liquid injection phase is collected through liquid collecting channels  66  and  68 . 
     These collecting channels behave as sucking channels when valve devices  72  and  74  are commanded to be opened and pump device  46  of  FIG. 3  is commanded to operate by causing depression in the upstream circuit. 
     This will then cause the liquid overflow to be sucked into channels  66  and  68  and pipes  76  and  78  until reaching pump device  46 . 
     The collected residual liquid is then supplied by pump device  46  to tank  50  for being stored before any recycling. 
     Since a pump device is used in this embodiment the angle of inclination of the channels may be much smaller than 30° relative to the horizontal plane, e.g. in the order of several degrees. 
     According to an alternative embodiment, no pump device is necessary for collecting the liquid. As the collecting channels  66  and  68  are inclined relative to axis A with the outlet ends located in a lower position than the inlet ends  66   c ,  68   c , the liquid may be collected by gravity inside the channels when valve devices  72  and  74  are caused to be opened and venting to the atmosphere is performed. 
     The collected liquid may then be further conveyed by gravity to a tank or reservoir as tank  50  of  FIG. 2  for subsequently recycling the liquid during another injection phase. 
     It is to be noted that valve devices are present in the liquid circuit in order to prevent any gravitational flowing of liquid into the collecting channels during the liquid injection phase. 
     As for  FIG. 1  embodiment compressed air injection means may be used in connection with  FIG. 3  embodiment. 
     According to a first variant embodiment, compressed air may be used with  FIG. 3  embodiment in which a pump device is involved to extract the residual liquid so as to enhance the efficiency of the liquid collecting operation. 
     According to a second variant embodiment, compressed air may be used with  FIG. 3  embodiment in which the residual liquid is collected through the collecting channels thanks to gravity. This dramatically reduces the time necessary for collecting the liquid and therefore the cycle time of the whole process. 
     All that has been described above in connection with  FIG. 1  embodiment still applies here and will not be repeated. 
     Thanks to liquid collecting means waste of liquid is dramatically reduced in the course of performance of the blowing and filling method. 
     Furthermore, the presence of liquid drops within the mold and, in particular, on the inner surface of the walls of the two mold halves is dramatically reduced or even avoided. 
     It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.