Method for heating a preform and corresponding method for forming a container

Patent metadata

Field	Value
Publication number	US-2023278275-A1
Application number	US-202118007344-A
Country	US
Kind code	A1
Filing date	Jul 30, 2021
Priority date	Aug 3, 2020
Publication date	Sep 7, 2023
Grant date	—

Abstract

Method for heating a preform ( 1 ) comprising: introducing the preform ( 1 ) into a heating apparatus ( 5 ) comprising an array of infrared emitters ( 50 ) arranged in multiple columns (Cj) and multiple rows (Ri), orienting angularly the preform at an input angular position by rotating the preform around the longitudinal axis; setting power levels of the infrared emitters ( 50 ) so as to divide the array of infrared emitters ( 50 ) into subsets of columns (SCn), each subset of columns (SCn) generating heat at a different power level from an adjacent subset of columns (SCn); and heating the preform ( 1 ) with the array of infrared emitters ( 50 ) while translating the preform ( 1 ) in a direction parallel to the rows (Ri) of the array at a translation speed, and simultaneously rotating said preform ( 1 ) around its longitudinal axis (A 1 ) in front of said infrared emitters ( 50 ) at a rotation speed.

First claim

1 . A method for heating a preform comprising an open neck portion at a first end, a closed base portion at a second end, and a body portion extending along a longitudinal axis between the neck portion and the base portion, said preform being made in a thermoplastic material having no strain hardening properties or low strain hardening properties, said method comprising the following steps:
introducing the preform into a heating apparatus comprising an array of infrared emitters arranged in multiple columns and multiple rows, the preform and said array being disposed such that the longitudinal axis and the columns of the array of infrared emitters are parallel or directed obliquely with respect to each other; orienting angularly the preform at an input angular position by rotating the preform around the longitudinal axis; setting power levels of the infrared emitters so as to divide the array of infrared emitters into subsets of columns, each subset of columns generating heat at a different power level from an adjacent subset of columns; heating the preform with the array of infrared emitters while translating the preform in a direction parallel to the rows of the array at a translation speed, and simultaneously rotating said preform around its longitudinal axis in front of said infrared emitters at a rotation speed, the rotation speed, the translation speed, the input angular position and the power levels of the infrared emitters being set so that the power levels of the subsets of columns facing at least three zones of the body portion extending longitudinally are different from the power levels of the subsets of columns facing the rest of the body portion, said zones of the body portion extending relative to one another in a polygonal array, the power levels of the subsets of columns facing said zones of the body portion being set higher than the power levels of the subsets of columns facing the rest of the body portion if and only if said zones of the body portion have a greater thickness than the thickness of the rest of the body portion.

2 . A method for heating according to claim 1 , wherein the thermoplastic material of the preform presents a density less than or equal to 1 g/cm's.

3 . A method for heating according to claim 1 , wherein the thermoplastic material is polypropylene, polyethylene.

4 . A method for heating according to claim 1 , wherein the thermoplastic material is biodegradable.

5 . A method for heating according to claim 4 , wherein the thermoplastic material is polyhydroxyalkanoates.

6 . A method for heating according to claim 1 , wherein the number of columns for each subset of columns is determined according to the dimension of the emitters in the direction of the preform translation, the perimeter of the transverse cross-section of the body portion, the translation speed and the rotation speed.

7 . A method for heating according to claim 1 , wherein when setting the power levels of the heat generated by the infrared emitters, the array of infrared emitters is divided into sub-arrays, each sub-arrays comprising a number of subsets of columns equal to twice the number of said longitudinal zones of the body portion, the power levels of said subsets of columns being set by alternating between two different power levels from one subset of columns to an adjacent subset of columns.

8 . A method for heating according to claim 7 , wherein the power levels of the infrared emitters of all the sub-arrays are set similarly.

9 . A method for heating a preform according to claim 1 , wherein said body portion comprising at least three zones extending longitudinally and relative to one another in a polygonal array, said zones presenting a greater thickness than the rest of the body portion, wherein the rotation speed, the translation speed, the input angular position and the power levels of the infrared emitters are set so that the power levels of the subsets of columns facing said zones of the body portion are higher than the power levels of the subsets of columns facing the rest of the body portion.

10 . A method for heating a preform according to claim 1 , wherein said body portion having a uniform thickness along any transverse cross-section, wherein the rotation speed, the translation speed, the input angular position and the power levels of the infrared emitters are set so that the power levels of the subsets of columns facing said zones of the body portion extending longitudinally are different from the power levels of the subsets of columns facing the rest of the body portion, said zones of the body portion extending relative to one another in a polygonal array, the power levels of the subsets of columns facing said zones of the body portion being set lower than the power levels of the subsets of columns facing the rest of the body portion.

11 . A method for heating a preform according to claim 1 , wherein the body portion comprises between three and ten zones extending longitudinally and relative to one another in a polygonal array.

12 . A heating apparatus configured to implement a method for heating, said heating apparatus comprising:
an array of infrared emitters arranged in multiple columns and multiple rows; and a holder, orienting a preform at an input angular position, translating along a direction parallel to the rows at a settable translation speed and simultaneously rotating said preform around its longitudinal axis in front of said infrared emitters at a settable rotation speed.

13 . A method for manufacturing a container, using a preform comprising an open neck portion at a first end, a closed base portion at a second end, and a body portion extending along a longitudinal axis between the neck portion and the base portion, said preform being made in a thermoplastic material having no strain hardening properties or low hardening, said method for manufacturing comprising the following steps:
heating the preform comprising an open neck portion at a first end, a closed base portion at a second end, and a body portion extending along a longitudinal axis between the neck portion and the base portion, said preform being made in a thermoplastic material having no strain hardening properties or low strain hardening properties, said method comprising the following steps: introducing the preform into a heating apparatus comprising an array of infrared emitters arranged in multiple columns and multiple rows, the preform and said array being disposed such that the longitudinal axis and the columns of the array of infrared emitters are parallel or directed obliquely with respect to each other; orienting angularly the preform at an input angular position by rotating the preform around the longitudinal axis; setting power levels of the infrared emitters so as to divide the array of infrared emitters into subsets of columns, each subset of columns generating heat at a different power level from an adjacent subset of columns; heating the preform with the array of infrared emitters while translating the preform in a direction parallel to the rows of the array at a translation speed, and simultaneously rotating said preform around its longitudinal axis in front of said infrared emitters at a rotation speed, the rotation speed, the translation speed, the input angular position and the power levels of the infrared emitters being set so that the power levels of the subsets of columns facing at least three zones of the body portion extending longitudinally are different from the power levels of the subsets of columns facing the rest of the body portion, said zones of the body portion extending relative to one another in a polygonal array, the po

Assignees

• Nestle Sa

Inventors

• Kannengiesser Damien Jean-Philippe

Classifications

• B29C49/12

  Stretching rods · CPC title

• B29C49/0005

  characterised by the material · CPC title

• B29C49/6445 Primary

  through the preform length · CPC title

• B29C49/071

  Preforms or parisons characterised by their configuration, e.g. geometry, dimensions or physical properties · CPC title

• B29C2049/024

  not using inherent heat of the preform, i.e. 2 step blow moulding · CPC title