Container, method and apparatus for making the same

Abstract

A container ( 1 ) having a body and a rim ( 3 ) defining an opening for the container, the container being made of a material such as PET or PEN, is manufactured in a two-stage process. The first stage comprises injection moulding a preform ( 15 ) which has a rim ( 3 ) formed at its mouth and a continuous body-forming portion ( 32 ) extending across the preform from the inner periphery ( 19 ) of the rim, the rim having an outwardly-directed extent and including a downwardly-extending portion ( 21 ) spaced outwardly from the inner periphery and an outwardly-extending portion ( 5,6,29 ) located outwardly of the downwardly extending portion. In the second stage the preform is placed in a moulding cavity ( 56 ) of a blow moulding apparatus ( 7 ) at an elevated temperature with the preform being located by means of the rim ( 3 ). The body-forming portion expands in the cavity to form the container side wall ( 20 ) and bottom wall ( 2 ). The upper region ( 18 ) of the side wall contacts the downwardly-extending portion ( 21 ) of the rim such as to form a box section ( 25 ). The side wall ( 20 ) has at its upper side region a step ( 23 ) above which the diameter of the cavity is substantially equal to or approaches the diameter of the downwardly-extending portion ( 21 ) of the rim. Below the step ( 23 ) the diameter is less than the diameter of the inner periphery of the rim and tapers therefrom inward downwardly to the bottom wall ( 2 ) at an acute angle, whereby the containers can internest.

1 . A container having a body and a rim defining an opening for the container, the container being made of a material which is susceptible to deformation when heated, the container comprising: 
 a rim formed at the mouth of the container, the rim having an outwardly-directed extent and including a downwardly-extending portion spaced outwardly from the inner periphery and an outwardly-extending portion located outwardly of the downwardly-extending portion;    a container side wall and bottom wall, the upper region of the side wall contacting the downwardly-extending portion of the rim;    characterized in that:    the upper region of the side wall contacts the downwardly-extending portion of the rim such as to form a box section; and    the side wall of the container has at its upper side region a narrowing side wall section above which the diameter of the side wall is substantially equal to or approaches the diameter of the downwardly-extending portion of the rim and below which the diameter is less than the diameter of the inner periphery of the rim and tapers therefrom inward downwardly to the bottom wall at an acute angle, whereby like containers can internest.    
   
   
       2 . A container according to  claim 1 , in which the container material comprises polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or a PET and PEN blend.  
   
   
       3 . A container according to  claim 1 , in which the rim has an outwardly-extending portion radially beyond the downwardly-extending portion.  
   
   
       4 . A container according to  claim 3 , in which the outwardly-extending portion has a peripheral flange to assist in manual grasping of the container when nested with another like container.  
   
   
       5 . A container according to  claim 1 , in which the rim has a radially inner inverted U section, then a V shaped groove, and finally an inverted V section.  
   
   
       6 . A container according to  claim 5 , in which the downwardly-extending portion extends downwardly from the V shaped groove.  
   
   
       7 . A container according to  claim 1 , in which said acute angle is between 7 and 11 degrees.  
   
   
       8 . A container according to  claim 1 , further including radially-extending reinforcing ribs spaced around the periphery of the rim of the container.  
   
   
       9 . A container according to  claim 1 , in which the narrowing side region comprises a step above which the side wall is of substantially constant diameter.  
   
   
       10 . A container according to  claim 1 , in which above the narrowing side region the container is formed with outwardly extending external ribs, the diameter of the container widening relatively rapidly in the region of the external ribs to approach the diameter of the downward extension.  
   
   
       11 . A container according to  claim 1 , further comprising a lid for the container, the lid conforming with the upper surface of the rim.  
   
   
       12 . A container according to  claim 11 , in which the lid sealingly engages the rim of the container and comprises two sealing elements one on the top and the other at the side of the portion of the lid engaging the rim.  
   
   
       13 . A container according to  claim 11 , including a flap at the side of the lid to assist removal thereof.  
   
   
       14 . A method of manufacturing a container having a body and a rim defining an opening for the container, the container being made of a material which is susceptible to deformation when heated, the method comprising the steps of: 
 injection moulding in an injection-moulding apparatus a preform which has a rim formed at its mouth and a continuous body-forming portion extending across the preform from the inner periphery of the rim, the rim having an outwardly-directed extent and including a downwardly-extending portion spaced outwardly from the inner periphery and an outwardly-extending portion located outwardly of the downwardly-extending portion;    placing the preform in a moulding cavity of a pressure moulding apparatus at an elevated temperature with the preform being located by means of the rim; and    moving the body-forming portion in the pressure moulding apparatus downwardly and outwardly whereby the body-forming portion expands in the cavity to form the container side and bottom walls, the upper region of the side wall contacting the downwardly-extending portion of the rim, and the rest of the body-forming portion contacting the sides of the cavity to form a shape defined by the interior shape of the cavity;    characterized in that:    the upper region of the side wall contacts the downwardly-extending portion of the rim such as to form a box section; and    the interior of the moulding cavity of the pressure moulding apparatus is shaped to define the side and bottom walls of the container with the cavity having at its upper side region a narrowing side wall section above which the diameter of the cavity is substantially equal to or approaches the diameter of the downwardly-extending portion of the rim and below which the diameter is less than the diameter of the inner periphery of the rim and tapers therefrom inward downwardly to the bottom wall at an acute angle, whereby the resultant containers can internest.    
   
   
       15 . A method according to  claim 14 , in which the container material comprises polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or a PET and PEN blend.  
   
   
       16 . A method according to  claim 14 , in which the injection moulding step forms the rim with an outwardly-extending portion radially beyond the downwardly-extending portion.  
   
   
       17 . A method according to  claim 16 , in which the outwardly-extending portion has a peripheral flange to assist in manual grasping of the container when nested with another like container.  
   
   
       18 . A method according to  claim 14 , in which the injection moulding step forms the rim with a radially inner inverted U section, then a V shaped groove, and finally an inverted V section.  
   
   
       19 . A method according to  claim 18 , in which the downwardly-extending portion extends downwardly from the V shaped groove.  
   
   
       20 . A method according to  claim 14 , in which said acute angle is between 7 and 11 degrees.  
   
   
       21 . A method according to  claim 14 , further including radially-extending reinforcing ribs spaced around the periphery of the rim of the container.  
   
   
       22 . A method according to  claim 14 , in which the cavity of the pressure moulding apparatus is shaped such that the narrowing side region comprises a step above which the cavity is of substantially constant diameter.  
   
   
       23 . A method according to  claim 14 , in which the cavity of the pressure moulding apparatus is shaped such that above the narrowing side region the container is formed with outwardly extending external ribs, the diameter of the container widening relatively rapidly in the region of the external ribs to approach the diameter of the downward extension.  
   
   
       24 . A method according to  claim 14 , in which the pressure moulding apparatus is blow moulding apparatus.  
   
   
       25 . A method according to  claim 14 , in which the step of moving the body-forming portion is assisted by mechanical stretching of the body-forming portion in the pressure moulding apparatus.  
   
   
       26 . A method according to  claim 14 , further comprising the step of providing a lid for the container, the lid conforming with the upper surface of the rim.  
   
   
       27 . A method according to  claim 26 , in which the lid sealingly engages the rim of the container and comprises two sealing elements one on the top and the other at the side of the portion of the lid engaging the rim.  
   
   
       28 . A method according to  claim 26 , including a flap at the side of the lid to assist removal thereof.  
   
   
       29 . Apparatus for manufacturing a container having a body and a rim defining an opening for the container, the container being made of a material which is susceptible to deformation when heated, the apparatus comprising: 
 an injection-moulding apparatus adapted to injection-mould a preform which has a rim formed at its mouth and a continuous body-forming portion extending across the preform from the inner periphery of the rim, the rim having an outwardly-directed extent and including a downwardly-extending portion spaced outwardly from the inner periphery and an outwardly-extending portion located outwardly of the downwardly-extending portion;    a pressure moulding apparatus having a moulding cavity;    means for placing the preform in the moulding cavity of the pressure moulding apparatus at an elevated temperature with the preform being located by means of the rim; and    means in the pressure moulding apparatus for moving the body-forming portion downwardly and outwardly whereby the body-forming portion expands in the cavity to form the container side and bottom walls, the upper region of the side wall contacting the downwardly-extending portion of the rim, and the rest of the body-forming portion contacting the sides of the cavity to form a shape defined by the interior shape of the cavity;    characterized in that:    the cavity is so shaped that the upper region of the side wall contacts the downwardly-extending portion of the rim such as to form a box section; and    the interior of the cavity in the pressure moulding apparatus is shaped to define the side and bottom walls of the container with the cavity having at its upper side region a narrowing side wall section above which the diameter of the cavity is substantially equal to or approaches the diameter of the downwardly-extending portion of the rim and below which the diameter is less than the diameter of the inner periphery of the rim and tapers therefrom inward downwardly to the bottom wall at an acute angle, whereby containers formed by the apparatus can internest.    
   
   
       30 . Apparatus according to  claim 29 , in which the injection moulding apparatus forms the rim with an outwardly-extending portion radially beyond the downwardly-extending portion.  
   
   
       31 . Apparatus according to  claim 30 , in which the outwardly-extending portion comprises a peripheral flange to assist in manual grasping of the container when nested with another like container.  
   
   
       32 . Apparatus according to  claim 29 , in which the injection moulding apparatus forms the rim with a radially inner inverted U section, then a V shaped groove, and finally an inverted V section.  
   
   
       33 . Apparatus according to  claim 32 , in which the downwardly-extending portion extends downwardly from the V shaped groove.  
   
   
       34 . Apparatus according to  claim 29 , in which said acute angle is between 7 and 11 degrees.  
   
   
       35 . Apparatus according to  claim 29 , in which the injection moulding apparatus is further shaped to form radially-extending reinforcing ribs spaced around the periphery of the rim of the container.  
   
   
       36 . Apparatus according to  claim 29 , in which the cavity of the pressure moulding apparatus is shaped such that the narrowing side region comprises a step above which the cavity is of substantially constant diameter.  
   
   
       37 . Apparatus according to  claim 29 , in which the cavity of the pressure moulding apparatus is shaped such that above the narrowing side region the container is formed with outwardly extending external ribs, the diameter of the container widening relatively rapidly in the region of the external ribs to approach the diameter of the downward extension.  
   
   
       38 . Apparatus according to  claim 29 , in which the pressure moulding apparatus is blow moulding apparatus.  
   
   
       39 . Apparatus according to  claim 29 , in which the pressure moulding apparatus includes means for mechanical stretching of the body-forming portion.  
   
   
       40 . Apparatus according to  claim 29 , further comprising means for forming a lid for the container, the lid conforming with the upper surface of the rim.  
   
   
       41 . Apparatus according to  claim 40 , in which the lid sealingly engages the rim of the container and comprises two sealing elements one on the top and the other at the side of the portion of the lid engaging the rim.  
   
   
       42 . Apparatus according to  claim 40 , including a flap at the side of the lid to assist removal thereof.  
   
   
       43 . A container manufactured using the method of  claim 14.