Method and Installation for the Production of Containers

Abstract

The invention relates to a method of producing a container from a thermoplastic blank ( 2 ), comprising: a step in which the blank ( 2 ) is heated using at least one beam ( 22 ) of coherent electromagnetic radiation, and a step in which the container is formed from the blank ( 2 ) thus heated. The invention also relates to an installation ( 1 ) which is used to produce containers ( 2 ) and which comprises a unit ( 16 ) for heating the blanks ( 2 ) in order to form containers from the blanks ( 2 ) thus heated. The inventive installation ( 1 ) defines a path ( 23 ) along which the blanks ( 2 ) travel inside the heating unit ( 16 ). In addition, the heating unit ( 16 ) comprises at least one coherent electromagnetic radiation source ( 26 ) which is directed towards a zone ( 25 ) that is located on the aforementioned path ( 23 ).

1 - 34 . (canceled) 
   
   
       35 . A method for producing a container from a thermoplastic parison, which involves:
 a step of heating the parison performed by means of at least one beam of coherent electromagnetic radiation, then   a step of forming the container from the parison thus heated, the method being characterized in that the heating of the parison is performed by means of a plurality of superposed beams of electromagnetic radiation.   
   
   
       36 . The method as claimed in  claim 35 , in which the heating of the parison is performed by means of a plurality of adjacent beams of electromagnetic radiation. 
   
   
       37 . The method as claimed in  claim 35 , in which each beam is planar. 
   
   
       38 . The method as claimed in  claim 35 , in which each beam is directed in a predetermined overall direction and in which, during the heating step, the parison is at least locally made to follow a path substantially perpendicular to the direction of the beam. 
   
   
       39 . The method as claimed in  claim 35 , in which each beam is directed in a predetermined overall direction and in which, in the heating step, the parison is at least locally made to follow a path substantially parallel to the overall direction of the beam. 
   
   
       40 . The method as claimed in  claim 35 , in which, in the heating step, the parison is rotated about a predetermined axis. 
   
   
       41 . The method as claimed in  claim 40 , in which said axis of rotation coincides with an axis of revolution of the parison. 
   
   
       42 . The method as claimed in  claim 35 , in which, with the parison having a neck and a body, the beam of electromagnetic radiation is directed toward the body of the parison. 
   
   
       43 . The method as claimed in  claim 42 , in which, during the heating step, the neck of the parison is directed upward. 
   
   
       44 . The method as claimed in  claim 42 , in which the neck of the parison is ventilated. 
   
   
       45 . The method as claimed in  claim 35 , in which, in the heating step, the beam is reflected at least once off a reflective surface. 
   
   
       46 . The method as claimed in  claim 35 , in which said beam is a laser beam. 
   
   
       47 . The method as claimed in  claim 35 , in which the radiation from the beam is infrared radiation. 
   
   
       48 . The method as claimed in  claim 47 , in which the wavelength of the radiation is less than or equal to about 1600 nm. 
   
   
       49 . The method as claimed in  claim 48 , in which the wavelength of the radiation is between about 700 nm and 1600 nm. 
   
   
       50 . An installation for producing containers from thermoplastic parisons, which comprises a heating unit for heating the parisons with a view to forming the containers from the parisons thus heated, the installation defining a path but the parisons are intended to follow within the heating unit, characterized in that the heating unit comprises at least one source of coherent electromagnetic radiation directed toward a region situated on the path of the parisons. 
   
   
       51 . The installation as claimed in  claim 50 , in which, with the path of the parisons being substantially linear, said plurality of sources of radiation is directed transversely with respect to said path. 
   
   
       52 . The installation as claimed in  claim 51 , in which the heating unit comprises a row of adjacent radiation sources arranged parallel to the path. 
   
   
       53 . The installation as claimed in  claim 52 , in which the heating unit comprises several superposed rows of radiation sources arranged parallel to the path. 
   
   
       54 . The installation as claimed in  claim 53 , in which the heating unit comprises a chamber comprising a first wall and a second wall facing one another and substantially parallel to the path of the parisons, these walls being positioned one on each side of this path and together delimiting an internal volume, the first wall being equipped with a plurality of superposed parallel slits facing each of which there is positioned, on the opposite side to the internal volume, a row of radiation sources. 
   
   
       55 . The installation as claimed in  claim 54 , in which the second wall at least, on the same side as the internal volume, has a reflective internal surface. 
   
   
       56 . The installation as claimed in  claim 54 , in which the heating unit comprises a ventilation system able to generate an air flow passing through a region situated vertically in line with said chamber. 
   
   
       57 . The installation as claimed in  claim 50 , in which, with the path of the parisons being substantially linear, said source of radiation is directed parallel to said path. 
   
   
       58 . The installation as claimed in  claim 56 , which comprises an opaque screen positioned facing the source of radiation. 
   
   
       59 . The installation as claimed in  claim 56 , which comprises at least two successive heating units. 
   
   
       60 . The installation as claimed in  claim 50 , in which, with the path of the parisons being substantially circular, the heating unit comprises a plurality of successive chambers positioned along the path, each chamber having two cylindrical walls facing each other and positioned one on each side of the path and together defining an internal cavity, each wall having several adjacent reflective facets facing toward the cavity, the source of electromagnetic radiation being directed toward one of these facets and the facets are not exactly parallel with their pair but together define an angle of a few degrees. 
   
   
       61 . The installation as claimed in  claim 60 , which comprises an opaque screen adjacent to one of the facets. 
   
   
       62 . The installation as claimed in  claim 50 , in which, with the parisons having an axis of revolution, the heating unit comprises means for rotating the parisons about their axis. 
   
   
       63 . The installation as claimed in  claim 50 , in which the source of coherent electromagnetic radiation is a laser source. 
   
   
       64 . The installation as claimed in  claim 63 , in which the source of coherent electromagnetic radiation is a laser diode. 
   
   
       65 . The installation as claimed in  claim 64 , in which the laser diode is designed to emit a planar laser beam. 
   
   
       66 . The installation as claimed in  claim 64 , in which the heating unit comprises at least one block or one array of juxtaposed laser diodes.