Abstract:
A molding apparatus and method for creating a molded object that incorporate a mold with a mold cavity, a mold core disposed within the mold cavity, and a reciprocating sleeve insertable between the mold core and the mold cavity. The apparatus and method include injecting molten plastic between the core and the sleeve forming a preform object, then retracting the sleeve and expanding the preform object by blow molding, using pressurized fluid provided through jets in the mold core, until the object expands to fill the mold cavity. The apparatus and method further include thermal conditioning of the sleeve when it is retracted to create a temperature profile in the sleeve that is then applied to the preform object, thereby providing finer control of the temperature profile of the preform object before the final blow molding step.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a blow molding apparatus and method for creating molded objects, more particularly to an injection and blow molding apparatus and method that allows use of a conventonal injection molding machine to produce blow molded objects. 
       BACKGROUND OF THE INVENTION 
       [0002]    Plastic bottles are typically characterized as having a wide hollow body and a narrow neck. To form such plastic bottles it is typical to use a blow molding process. 
         [0003]    An injection blow molding machine typically has three stations with a central turret that transfers the material which is being processed from one station to another. At the first station, molten plastic is injected into a heated preform mold around a core rod to form a preform object. The preform mold separates and the turret transfers the core rod and preform object to a second station. The second station is the blow mold station. The blow mold has a cavity with a neck diameter and a body diameter. The body diameter is usually greater than the neck diameter. With the core rod disposed in the blow mold, compressed air or other gas is injected through the core causing the preform object to expand to the diameter of the mold. The diameter of the object in the neck area remains relatively unchanged. The blow mold then is opened and the core is transferred to a third station where the blow molded bottle is stripped from the core. In the typical machine, a plurality of such bottles are made simultaneously, such that there are a plurality of cores and mold cavities used in the process. 
         [0004]    One benefit of the above process is that the molds can be designed to incorporate different temperature zones. The molds typically incorporate a heating element that keeps the temperature of the body region of the molds elevated. They also may incorporate a cooling element that keeps the temperature of the neck region low. Keeping the temperature of the body region of the preform object warm helps facilitate the expansion of this region in the blow mold. Keeping the temperature of the neck region of the preform object cool helps control the neck molding it to a precise size. 
         [0005]    Temperature control is also an important feature for bottles used in certain industries. For instance, in the cosmetics industry it is important for sample bottles to have a particular finish. Precise control of temperature in different temperature regions allows control of the finish of the molded bottles. 
         [0006]    The deficiency of the typical injection blow molding machine is that a very long set-up time is required, limiting production and increasing costs. The three stations and two molds that must interact with an independent rotating turret, so significant time is required in set-up of a production run to assure that these different components are properly aligned before production can begin. 
         [0007]    In contrast to injection blow molding, a standard injection molding apparatus has a mold is closed about a core or series of cores, and molten plastic is injected into the spacing between the cores and the mold. The mold separates and the molded object is stripped from the core. A standard injection molding machine has one station and is relatively fast to set up for molding operations. The deficiency in conventional injection molding is that there is a limitation on the shape of hollow articles such as bottles molded in an injection molding machine. Essentially, injection molding of bottles is limited to cylindrical bottle of constant diameter. This is because in order for a bottle to be removed from the cores after molding, for the core diameter at the body section cannot be larger than the diameter of the bottle neck. Furthermore, if a mold shape is made with a larger diameter area for the body and a smaller diameter area for the neck, the extruded plastic injected into the mold will fill the space resulting molded product with extremely thick walls. Thus the bottle shapes that can be formed using injection molding are very limited. 
         [0008]    What is needed is an apparatus that can combine the set-up simplicity of a standard injection molding machine with the versatility y of an injection blow molding machine. It would be beneficial if such an apparatus could limit the number of mold parts necessary to form a bottle with cavities of different diameters. It would also be beneficial if such an apparatus could form these bottles at a single station. 
       SUMMARY OF THE INVENTION 
       [0009]    These and other objects are achieved by providing an injection molding apparatus that incorporates a mold with a mold cavity, a core disposed within the mold cavity, and a reciprocating sleeve insertable between the core and the mold. 
         [0010]    Another aspect of the molding apparatus is to dispose the sleeve within an expanded region of the mold cavity, inject extruded plastic between the sleeve and the core to form a preform object, then to retract the sleeve and expand the object by blow molding within the expanded region to form a blow molded object. 
         [0011]    It is a further aspect for the sleeve to be temperature controlled to condition the injected molten plastic. The temperature conditioning can be obtained by temperature controlled temperature conditioner which comprises heated or cooled fluid filled channels or electric heating located adjacent to the sleeve in a retracted position. 
         [0012]    Other objects of the invention and its particular features and advantages will become more apparent from consideration of the following drawings and accompanying description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a top plan schematic view of an injection molding apparatus in accordance with one embodiment of the invention. 
           [0014]      FIG. 2  is a detailed top view in cross-section of the molding apparatus of  FIG. 1 , showing mold elements brought together to form a mold cavity around a core and a sleeve inserted into a mold cavity. 
           [0015]      FIG. 3  is a detailed top view in cross-section of the molding apparatus of  FIG. 1  showing the sleeve retracted from the mold cavity and a temperature conditioner disposed about an outer surface of the sleeve. 
           [0016]      FIG. 4  is detailed top view in cross-section of the molding apparatus of  FIG. 1  with the sleeve retracted from the mold cavity and a temperature conditioner disposed about an inner surface of the sleeve. 
           [0017]      FIG. 5  is a schematic top view of the molding apparatus of  FIG. 1  with the mold elements separated and the core retracted. 
           [0018]      FIG. 6  is a detailed side view in cross-section through a right component with a plurality of mold cavities. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]      FIG. 1  depicts a top down cross-sectional view of injection molding apparatus  100  in a closed state. Injection molding apparatus  100  comprises a left component  200 , a right component  300 , a left mold element  250 , a right mold element  350 , an arm  400  and a base component  600 . 
         [0020]    Extending into the proximal end of apparatus  100  is arm  400 . Arm  400  is disposed in the region where the left  200  and right  300  components are brought together. The left  200  and right  300  components comprise regions that receive arm  400 , such that when the components are brought together, a portion of the arm  400  is in flush contact with the components  200 ,  300 . Arm  400  comprises a retaining component  410 , a sliding element  411  and a mold core  420 . Arm  400  and retaining component  410  are coupled to each other by pin  401 . Core  420  comprises a cylindrical receiving element  430  and a cylindrical actuating element  440 . Cylindrical receiving element  430  is coupled to sliding element  411  at the proximal end of core  420 . Sliding element  411  enables core  420  to move in the proximal and distal directions within arm  400 . Moving sliding element  411  in the distal direction inserts actuating element  440  and receiving element  430  through opening  412  of retaining component  410 . As a result, receiving element  430  is partially disposed within retaining component  410  and sliding element  411 . Moving sliding element  411  in the proximal direction retreats receiving element  430  and actuating element  440  through opening  412 . Preferably, mold core  420  is coated with a release coating such as PTFE. 
         [0021]    Receiving element  430  is characterized by a proximal portion  435  with a diameter that is greater than a distal portion  436  and corresponds to the diameter of the inner chamber formed by sliding element  411  and retaining component  410 . When sliding element  411  is moved in a distal direction, distal portion  436  extends through opening  412  and has a diameter that corresponds to the inner diameter of opening  412 . 
         [0022]    Receiving element  430  is also characterized by a series of cylindrical inner chambers  431 - 433  that are formed within the proximal portion  435  and the distal portion  436 . The proximal portion  435  forms proximal chamber  431  and middle chamber  432 . The distal portion  436  forms distal chamber  433 . The proximal chamber  431  has a diameter that is greater that the middle chamber  432 , which is greater than the diameter of the distal chamber  433 . These chambers  431 - 433  are used as fluid channels through which pressurized fluid, such as air, will flow. 
         [0023]    The actuating element  440  is a male component, a portion of which is disposed within the receiving element  430 . Actuating element  440  is characterized by a series of regions  441 - 443  that extend from the proximal end to the distal end of element  440  and a stop  444  that is coupled to the proximal region  441 . The proximal region  441  has a diameter that is less than the diameter of the middle region  442 , which is less than the diameter of the distal region  443 . The outer diameter of distal region  443  corresponds to the outer diameter of distal portion  436  of receiving element  430 . The outer diameter of middle region  442  is less than the diameter of the distal chamber  433  so that a small separation exists between middle region  442  and distal portion  436  of receiving element  430 . As a result, the actuating element  443  comprises a distal transition region  445  between distal region  443  and middle region  442  that abuts a distal face  434  of receiving element  430 . It should be noted that transition region  445  and face  434  are sloped surfaces relative to the surface of distal region  443  and come into flush contact with each other. Actuating element  440  also comprises a proximal transition region  446  between proximal region  441  and middle region  422 . Proximal transition region  446  comprises a sloped surface similar to distal transition region  445 . Stop  444  is coupled to proximal region  441  and is disposed within proximal chamber  431 . Stop  444  has a diameter that corresponds to the diameter of proximal chamber  431  and is greater than middle chamber  432 . As a result, the movement of actuating element  443  in the proximal or distal direction is limited by distal transition region  445  and stop  444 . Motion in the distal direction is limited by stop  444  engaging proximal portion  435  forming middle chamber  432 . Motion in the proximal direction is limited by distal transition region  445  coming into contact with distal face  434 . 
         [0024]    Through the combination of these elements, pressurized fluid, such as air, can be used to act upon a preform object  101  formed about core  420 . Pressurized fluid is introduced to chambers  431 - 433  through arm  400 . The pressurized fluid engages proximal transition region  446  and induces the actuating element  440  to move in a distal direction. The movement of actuating element  440  causes a channel to open up between middle region  442 , distal transition region  445  and distal portion  436 . This permits the pressurized fluid to flow through the channel and act upon a preform object  101  formed about core  420 . The formation of a preform object about core  420  will be discussed in more detail below. 
         [0025]    Left  250  and right  350  mold elements are coupled to left  200  and right  300  components via pins  201 ,  301 ,  302 . Each mold element  250 ,  350  forms half of a cavity  500  used to form a preform object. Each mold element  250 ,  350  comprises a core region  251 ,  351 , a neck region  252 ,  352 , an expanded region  253 ,  353 , and a bubbler region  254 ,  354 . When the mold elements  250 ,  350  are brought together they form a complete mold with a core cavity  510 , a neck cavity  520 , an expanded cavity  530 , and a base cavity  540 . Further, when the mold elements  250 ,  350  are brought together and core  420  is extending through opening  412  in a distal direction, the core regions  251 ,  351 , neck regions  252 ,  352 , and expanded regions  253 ,  353  encompass the distal portion  436  of receiving element  430  and the distal region  443  of actuating element  440 . 
         [0026]    Core cavity  510  has a diameter that corresponds to the outer diameter of distal portion  436 . When the mold elements  250 ,  350  are brought together, core regions  251 ,  351  come into flush contact with core distal portion  436 . This prevents any plastic materials injected into cavities  520  and  530  from flowing about the distal portion  436  disposed within regions  251 ,  351 . 
         [0027]    Distally spaced from core regions  251 ,  351  are neck regions  252 ,  352 . Each neck region  252 ,  352  has a threaded profile that enables the neck of a preform object  103  to be threaded. Neck cavity  520  has a diameter that is greater than core cavity  510  but less than expanded cavity  530 . Further, this diameter is greater than the outer diameter of distal portion  436 . As a result, a space is formed between the neck regions  252 ,  352  and distal portion  436 . 
         [0028]    Distally spaced from neck regions  252 ,  352  are expanded regions  253 ,  353 . Expanded cavity  530  has a diameter that is greater than neck cavity  520 . The space formed between expanded regions  252 ,  352 , distal portion  436 , and distal region  443  is greater than the space formed between neck regions  252 ,  352  and distal portion  436 . As shown in  FIG. 3  and discussed in more detail below, the processing of a preform object  101  will enable an expanded object  105  to be formed. This processing also forms a space between the expanded object  105 , the distal portion  436 , and the distal region  443 . 
         [0029]    Distally spaced from each expanded region  253 ,  353  is a base region  254 ,  354  that is used to form a base cavity  540 . The diameter of the base cavity  540  corresponds to the outer diameter of sleeve  630 . When mold elements  250 ,  350  are brought together, the base regions  254 ,  354  come into contact with sleeve  630  and inhibit the ability of extruded plastic to flow within these regions  254 ,  354 . 
         [0030]    Left component  200  further comprises extruded molten plastic injector  210 . Injector  210  extends through left component  200  and left mold element  250 . Injector  210  comprises spout  211  that has an opening in neck region  252 . Injector  210  utilizes pressure to enable extruded plastic to be introduced into the space that separates core  420  from distal portion  436  and flow the extruded around the portion of core  420  disposed within the neck cavity  520  and expanded cavity  530 . This forms a preform object  101  with a cavity  102  and a neck  103  with a neck cavity  104 . The diameter of cavity  102  and neck cavity  104  will correspond to the outer diameter of distal portion  436  and distal region  443 . 
         [0031]    Mold elements  250 ,  350  further comprise heating elements  223 - 225  and  323 - 325  that are disposed within the bodies of mold elements  250 ,  350 . Heating elements  223 - 225  are spaced between injector  210  and pin  201  from the proximal end to the distal end of expanded region  253 . Likewise, heating elements  323 - 325  are spaced between pins  302  and  301  from the proximal end to the distal end of expanded region  353 . These heating elements  223 - 225  and  323 - 325  are coupled to corresponding heating elements  220 - 222  and  320 - 322  contained within left  200  and right  300  components. Heating elements  223 - 225  and  323 - 325  are utilized to temperature condition the injected extruded molten plastic to facilitate the processing of a preform object. Depending on the processing needs these elements  223 - 225  and  323 - 325  can be used to form temperature profiles from the proximal to the distal ends of expanded regions  253 ,  353 . 
         [0032]    Coupled to right component  300  is base component  600 . Base component  600  provides a surface against which the base of a preform object is formed. Base component  600  comprises a bubbler tube  610 , sleeve  630 , and sleeve conditioner  650 . Bubbler tube  610  comprises a base wall  611  at the proximal end of bubbler tube  610 . When the left  250  and right  350  mold elements are brought together, base wall  611  is disposed within bubbler cavity  540  and immediately adjacent to expanded cavity  530 . Base wall  611  is also disposed opposite to and spaced from the distal region  443  of actuating element  440 . The space between base wall  611  and actuating element  440  is used to partially form the base of a preform object  101 . 
         [0033]    Extending from base wall  611  in the distal direction is inner conditioning wall  612 . Disposed within bubbler tube  610  is bubbler cooling element  614 . Bubbler cooling element  614  has a diameter less than the inner diameter of inner conditioning wall  612  forming bubbler channel  613 . Through Base component  600  a cooling fluid is injected into and flows about channel  613 . The cooling fluid cools base wall  611  and inner conditioning wall  612 . In turn, this heat is removed from sleeve  630  and the preform object that is molded in the space between distal region  443  and base wall  611 . 
         [0034]    Disposed about inner conditioning wall  612  is sleeve  630 . The inner diameter of sleeve  630  corresponds to the outer diameter of inner conditioning wall  612 . The inner diameter of sleeve  630  also corresponds to the diameter of neck cavity  520 . The distal end of sleeve  630  is coupled to sliding element  632 . Sliding element  632  enables sleeve  630  to be inserted into expanded cavity  530  or retracted from expanded cavity  530  during the formation of a preform object. Sleeve  630  is inserted into expanded cavity  530  before extruded molten plastic is injected into neck cavity  520  and expanded cavity  530  and is disposed over the entire length of the expanded cavity  530 . This creates a sleeve cavity  530  with a diameter that corresponds to the diameter of neck cavity  520  and is a subset of expanded cavity  530 . When extruded molten plastic is injected into cavities  520 ,  530  by injector  210 , it flows into the space that separates core distal portion  436  from the neck regions  252 ,  352  and sleeve  630 . The extruded molten plastic also flows into the space that separates core distal region  443  from sleeve  630  and base wall  611 . This forms a preform object  101  with a cavity  102  and a neck  103  with a neck cavity  104 . The diameter of cavity  102  and neck cavity  104  will correspond to the outer diameter of distal portion  436  and distal region  443 . When the sleeve  630  is retracted, the proximal face  631  of sleeve  630  becomes coplanar with the proximal face of base wall  611 . The sleeve proximal face  631  in combination with the proximal face of base wall  611  comprise the surfaces against which the base of an expanded object  105  is formed. 
         [0035]    Disposed about sleeve  630  is sleeve conditioner  650 . The inner diameter of sleeve conditioner  650  corresponds to the outer diameter of sleeve  630 . Sleeve  630  slides between bubbler  610  and sleeve conditioner  650 . Sleeve conditioner  650  comprises temperature channels  651 - 656  that are spaced from the proximal end to the distal end of conditioner  650  about sleeve  630 . Each channel  651 - 656  provides a temperature zone that is used to temperature condition sleeve  630  when it is in a retracted state. Such temperature conditioning can be accomplished by flowing a thermally conductive fluid through channels  651 - 656 . Fluids that are either relatively hot or cool can flow through channels  651 - 656 . When a fluid with an elevated temperature is used, the heat is transferred through the thermally conductive material forming conditioner  650  and into sleeve  630 . This elevates the temperature of sleeve  630  in the localized region of each channel  651 - 656 . When a fluid with a lowered temperature is used, these channels  651 - 656  draw heat from sleeve  630  across the material forming conditioner  650  and into the fluid. This reduces the temperature of sleeve  630  in the localized region of each channel  651 - 656 . Depending on the processing needs for the preform object, it is possible for channel  651  to communicate with channel  654 , channel  652  to communicate with channel  655 , and channel  653  to communicate with channel  656 . During processing it is also possible for different areas of sleeve  630  to have different thermal characteristics from the proximal end to the distal end. Channels  651 ,  654  may have a thermally conductive fluid that provides a first temperature and channels  653 ,  656  may have a thermally conductive fluid that provides a second temperature that is elevated relative to the first temperature. As a result, the area of sleeve  630  disposed within the region of channels  651 ,  654  would be thermally conditioned to a temperature that corresponds to the first temperature and the area of sleeve  630  disposed within the region of channels  653 ,  656  would thermally conditioned to a temperature that corresponds to the second temperature. When the temperature conditioned sleeve  630  is inserted into expanded cavity  530 , the sleeve  630  transfers its temperature profile to the injected parison. The area of sleeve  630  associated with the first temperature may remove heat from the injected plastic in that localized area, while the area of sleeve  630  associated with the second temperature may transfer heat to the injected plastic in that localized area. The formation of a preform object with localized thermal characteristics assists in the formation of a preform object during subsequent processing. 
         [0036]      FIG. 4  shows another feature in which temperature conditioning of sleeve  630  is achieved utilizing inner conditioning wall  612 . This feature can be used in addition or alternative to channels  651 - 656 .  FIG. 4  shows inner wall  612  with fore elements  615  of a first thickness, mid elements  616  of a second thickness, and aft elements  617  of a third thickness. The thickness of mid elements  616  is less than the thickness of the fore  615  and aft  617  elements. With this feature it is possible for the outer diameter of all or a portion of elements  615 - 617  to be less than the inner diameter of sleeve  630 . This forms a space between sleeve  630  and elements  615 - 617 . Such a space affects the transfer of heat from bubbler  610  to sleeve  630  in the localized region of each element  615 - 617 . The greater the space between an element and a sleeve reduces the transfer heat from bubbler  610  to the sleeve  630  in the localized region of the element. As a result, the sleeve  630  is given a temperature profile that corresponds to the profile of elements  615 - 617 . Instead of or in addition to utilizing elements  615 - 617  with smaller diameters, it is also possible to substitute materials of different thermal conductivity properties. Elements  615  and  617  could comprise a first material, such as an alloy, with a high degree of thermal conductivity. Elements  616  could comprise a second material, such as a ceramic, with a lesser degree of thermal conductivity. This way the transfer of heat from bubbler  610  to sleeve  630  will depend on the thermal properties of the different elements. 
         [0037]      FIGS. 1 and 5  illustrate that the left  200  and right  300  components open and close using hydraulic pressure. Left component  200  comprises piston cavities  230 ,  231  that receive piston rods  330 ,  331 , which are coupled to right component  300 . When apparatus  100  is in a state as illustrated in  FIG. 1 , the left  200  and right  300  components are closed. Hydraulic pressure introduced into piston cavities  230 ,  235  acts upon the piston rods  330 ,  335  causing the left  200  and right  300  component to separate, as illustrated in  FIG. 5 . Left  200  and right  300  components also contain left  232 ,  233  and right  332 ,  333  separation channels respectively. Each separation channel has a large diameter cavity and a small diameter cavity. Spanning from each left separation channel to a respective right separation channel are separation rods  234 ,  334 . The ends of each separation rod  234 ,  334  contain a knob, the diameter of which is greater than the diameter of the associated separation rod and small diameter cavity. Upon separation of the left and right components, the knobs of each separation rod  234 ,  334 , limit the degree of separation of the components by engaging the associated small diameter cavity. 
         [0038]      FIGS. 1-5  illustrate the manner in which injection molding apparatus  100  operates. The left  200  and right  300  components are separated. The arm  400  is disposed in between components  200 ,  300 . The left  250  and right  350  mold elements are brought together by way of piston rods  330 ,  331  and piston cavities  230 ,  231  acting upon the left  200  and right  300  components. The left  200  and right  300  elements components close about arm  400 . The left  250  and right  350  mold elements are brought into flush contact with each other. At the same time, the bubbler regions  254 ,  354  come into flush contact with the outer surface of sleeve  630 . Sliding element  411  extends core  420  through opening  412 . Distal portion  436  and distal region  443  are now disposed within core cavity  510 , neck cavity  520  and expanded cavity  530 . Prior to sleeve  630  being inserted into expanded cavity  530 , channels  651 - 656  and/or elements  615 - 617  condition sleeve  630  with a temperature profile that corresponds to these channels and/or elements  615 - 617  Subsequently, sleeve  630  is inserted into expanded cavity  530 . As a result, a space is formed between the neck regions  252 ,  352 , the sleeve  630 , the base wall  611 , the end portion  436  and end region  443 . Injector  210  injects plastic into this space through neck region  252  such that it flows end portion  436  and end region  443 . This forms preform object  101  with cavity  102  and a neck  103  with a neck cavity  104 . The cavity  102  and neck cavity  104  have a first inner diameter that corresponds to the outer diameter of distal portion  436  and distal region  443 . During this period, the temperature profile of sleeve  630  is transferred to the preform object to assist in subsequent processing. After an appropriate period of time, sleeve  630  is retracted from expanded cavity  530 . Pressurized fluid, such as air, is then introduced into chambers  431 - 433  causing actuating element  440  to move in a distal direction forming a channel. The fluid that flows through this channel then acts upon preform object  101  formed about core  420  in expanded cavity  530 . The pressurized fluid forces the preform object  101  to expand in diameter such that the preform object expands to the expanded regions  253 ,  353  and the proximal face  631 . This forms expanded object  105  with expanded cavity  106 . The pressurized fluid does not act upon the plastic disposed in the neck cavity  520  and the plastic disposed between base wall  611  and the distal region  443  of core  420 . As a result, a blow molded object is formed, which has a threaded neck  103  with a neck cavity  104  that corresponds to the first diameter and an expanded cavity  106  that corresponds to a second diameter that is greater than the first diameter. With the plastic material expanded to expanded regions  253 ,  353 , heating elements  223 - 225  and  323 - 325  are able to further condition the expanded object  105  in these regions. After a period of time, the left  250  and right  350  mold elements are separated. Sliding element  411  moves core  420  in a distal direction and through opening  412 . This permits the expanded object  105  with neck  103  to be removed from about core  420  and collected for finishing. 
         [0039]      FIG. 6  depicts an alternative view of molding apparatus  100 . This view is a cross-sectional horizontal view through the right component  300 .  FIG. 6  shows that mold elements  250 ,  350  form a plurality of mold cavities  500 ,  500 ′. Mold cavity  500  is disposed above mold cavity  500 ′. These mold cavities  500 ,  500 ′ are to form preform objects  100 ,  100 ′ and expanded objects, not shown, in the same manner discussed above. 
         [0040]    One benefit of the above apparatus is that it simplifies the manner in which a bottle with an expanded cavity is formed. This apparatus eliminates the need for a rotating turret, three stations and the alignment of these elements. Overall, this apparatus simplifies the setup process. This apparatus also makes it possible to process molds having a large number of cavities, in the range of 16-24 cavities per mold, increasing the production rate relative to a turret type blow molding machine. Furthermore, the present invention does not have the horizontal or vertical stacking limitations associated with blow molding apparatuses. Finally, this apparatus provides simple motions improving the process time. 
         [0041]    Although the invention has been described with reference to a particular arrangement of parts, features, and materials these are not intended to exhaust all possible arrangements, features and materials, and indeed many modifications and variations will be ascertainable to those of skill in the art.