Method and device for producing a multipack and multipack

Abstract

A method for producing a multipack of containers includes heating a preform, cooling at least part of the preform, the at least part of the preform defining a cooled region, and producing a first container from the preform. The container has a reinforced wall portion formed from the cooled region. The method continues with applying adhesive to the reinforced wall portion, thereby forming an adhesive point and fixing a second container to the adhesive point.

Claims

1. A method for producing a multipack with first and second containers, wherein at least one container comprises a reinforced wall portion, said method comprising providing a preform for said first container, heating said preform and cooling at least a portion of said preform, said portion being a cooled portion, producing said first container from said preform, wherein said first container comprises a reinforced wall portion formed from said cooled portion of said preform, applying an adhesive to produce an adhesive point in said reinforced wall portion of said first container, and forming a multipack by fixing said second container to said adhesive point on said first container.

2. The method of claim 1, wherein cooling comprises exposing said cooled portion to a flow of cooling gas.

3. The method of claim 1, further comprising rotating said preform is rotated while cooling said cooled portion such that said cooled portion is ring shaped.

4. The method of claim 1, further comprising regulating cooling gas flow to control a thickness of said reinforced wall portion.

5. The method of claim 1, further comprising regulating cooling gas pressure so as to cause said reinforced wall portion to have a material thickness that is greater than thirty percent of a thickness of a container wall at a portion other than said reinforced wall portion.

6. The method of claim 1, wherein providing said preform comprises providing a preform having a constant thickness in said region.

7. The method of claim 1, wherein providing said preform comprises providing a preform that has been formed as one piece.

8. The method of claim 1, wherein producing said first container from said preform comprises stretch blow molding said preform.

9. The method of claim 1, wherein said second container comprises a reinforced wall portion that, when said multipack is formed, is adhesively bonded to said first container.

10. The method of claim 1, further comprising rotating said preform while said preform is being conveyed along said nozzle arrangement.

11. The method of claim 10, further comprising rotating said preform while said preform is being conveyed along a slot nozzle.

12. The method of claim 1, wherein cooling comprises causing said cooled region to be reduced by at least two degrees centigrade relative to a remainder of said preform.

13. The method of claim 12, wherein cooling comprises causing said cooled region to be reduced by at least five degrees centigrade relative to a remainder of said preform.

14. An apparatus for producing a multipack with at least two containers, said apparatus comprising a heater for heating preforms, a stretch blow molding device for producing containers from said heated preforms, a device for applying an adhesive for producing an adhesive point on said containers, and a combiner for combining said containers by said adhesive point to form a multipack, wherein said apparatus further comprises a gas nozzle arrangement configured to form a cooling zone on a portion of said heated preform.

15. The apparatus of claim 14, wherein said preform has a circumference, wherein said nozzle arrangement comprises a slot arranged at right angles to a movement direction of said preforms, wherein said slot has a length in said movement direction equal to said circumference.

16. The apparatus of claim 14, wherein said nozzle arrangement comprises a linear arrangement of a plurality of gas nozzles, wherein said gas nozzles are arranged at right angles to a direction of movement of said preforms through said apparatus, wherein said gas nozzles are formed as boreholes with a diameter of between half a millimeter and four millimeters.

17. A manufacture comprising a multipack comprising first and second containers, each having a container wall, wherein said first and second containers adhere together as a result of an adhesive at an adhesive point, wherein said first container was formed from a preform that, after having been heated, was cooled at a region of a wall thereof, said region defining a cooled region, wherein said cooled region comprises a reinforced wall portion to which adhesive was applied to form said adhesive point to which said second container was fixed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a container with a reinforced wall section being produced from a preform.

(2) FIG. 2 shows the container from FIG. 1 becoming part of a multipack; and

(3) FIG. 3 shows the container from FIG. 1 become part of a multipack with a container that also has a reinforced wall section.

DETAILED DESCRIPTION

(4) FIG. 1 shows a preform 3 being heated by an oven 21 as it makes its way to a blow molder 2. During the heating process H, the preform rotates in a rotation direction D. FIG. 1 also shows a first bottle 1a that the blow molder 22 makes from the preform 3. The preform 3, and hence the resulting bottle 1a, is made of polyethylene terephthalate.

(5) A nozzle arrangement within the oven 21 includes one or more nozzles to provide a cooling gas flow. In a typical embodiment, a four-edged tube having a row of boreholes forms the nozzle arrangement. Each borehole has about a one-millimeter diameter. A suitable cooling gas is compressed air with high relative humidity.

(6) The cooling gas flow causes a cooling process K that forms a cooling zone 8 that a portion of the preform 3 passes through during the heating process H. This cooling zone 8 is clearly defined in relation to the preform's direction of movement.

(7) The flow of cooling gas within the cooling zone 8 is regulated such that the portion of the preform 3 that passes through the cooling zone 8 becomes a distinct cooled region 4. This cooled region 4 ultimately becomes part of a container wall of a bottle 1a. In a preferred practice, the temperature of the cooled region 4 is about five degrees centigrade below that of the remainder of the preform 3.

(8) Upon completion of the heating process H and the cooling process K, the blow molder 22 receives the preform 3 and forms a first bottle 1a from it. This first bottle 1a has a container wall 16. The material from the cooled region 4 forms a portion of the container wall 16. This portion is what becomes a reinforced wall portion 2 of the container wall 16.

(9) The reinforced wall portion 2 is between 0.255 millimeters and 0.3 millimeters thick. The rest of the container wall 16 is about 0.15 millimeters thick. A transition region between the reinforced wall portion 2 and the rest of the container wall 16 takes the form of a sigmoidal curve, the precise shape of which depends on the temperature gradient between the cooled region 4 and the remainder of the preform 3.

(10) FIG. 2 shows the first bottle 1a together with a second bottle 1b being passed through a treatment unit 23 that fills, closes, and labels the bottles. In some embodiments, the treatment unit 23 fills the containers with a liquid that contains carbonic acid. The bottles 1a, 1b then joined to form a multipack 10.

(11) Some of the bottles 1a go to an adhesive applicator 24. The adhesive applicator 24 places a fluid adhesive on the bottle 1a to form an adhesive point 5 thereon. More specifically, the adhesive applicator 24 places the adhesive on the reinforced portion 2 of the bottle's container wall 16. The bottles 1a, 1b then undergo an alignment process A during which they are oriented in the correct positions to be joined into a multipack 10.

(12) After having been correctly oriented, the bottles 1a, 1b enter a combiner 25. The combiner 25 presses the containers 1a, 1b together to form an adhesive bond between them at the adhesive point 5. The combiner 25 maintains this pressure until the adhesive cools or hardens. In some cases, the combiner 25 adhesively bonds a carrying handle.

(13) FIG. 3 shows an alternative in which two cooling zones 8 define two cooled regions 4 that are separate from each other. These ultimately become two reinforced wall portions 2 on a container wall 16. The embodiment shown in FIG. 3 is otherwise similar to that shown in FIG. 2.

(14) FIG. 3 also shows an inspection device 26 following the treatment unit 23 and upstream of the adhesive applicator 24. The inspection device 26 screens out any containers 1a, 1b that may have defects or that are incorrectly filled. The containers 1a, 1b that pass the screening test then enter a combiner 25 to be formed into multipacks 10 that are then provide to a palleting device 27 for automatic palleting.

(15) Having described the invention, and a preferred embodiment thereof, what is claimed as new and secured by letters patent is: