Method for producing a plastic article and blow molding tool

• US 10,183,436 B2
• Filed: 01/14/2015
• Issued: 01/22/2019
• Est. Priority Date: 06/24/2009
• Status: Active Grant

• Current Assignee: Kautex Maschinenbau GmbH (Plastech Holding GmbH)
• Original Assignee: Kautex Maschinenbau GmbH (Plastech Holding GmbH)
• Inventors: Heim, Volker, Lichtenauer, Andreas, Moitzheim, Jurgen, Walbroel, Stefan
• Primary Examiner(s): Huson, Monica A
• Assistant Examiner(s): Grace, Kelsey C
• Application Number:
  US14/596,571
• Publication Number:
  US 20150125566A1
• Time in Patent Office: 1,469 Days
• CPC Class Codes: B29C 2049/2008 inside the article
• CPC Class Codes: B29C 2049/2073 Means for feeding the inserts into the mould, preform or parison, e.g. grippers
• CPC Class Codes: B29C 2049/4807 by movable mould parts in the mould halves
• CPC Class Codes: B29C 2049/4851 Side walls
• CPC Class Codes: B29C 2049/6091 Avoiding needle marks, e.g. insertion in sprue
• CPC Class Codes: B29C 2049/622 for venting air between preform and cavity, e.g. using venting holes, gaps or patterned moulds
• CPC Class Codes: B29C 2793/0063 Cutting longitudinally
• CPC Class Codes: B29C 2793/0081 before shaping
• CPC Class Codes: B29C 48/0017 combined with blow-moulding or thermoforming
• CPC Class Codes: B29C 48/0022 combined with cutting
• CPC Class Codes: B29C 48/09 Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
• CPC Class Codes: B29C 48/10 flexible, e.g. blown foils
• CPC Class Codes: B29C 49/04 Extrusion blow-moulding
• CPC Class Codes: B29C 49/04118 Means for supporting the extruded parison
• CPC Class Codes: B29C 49/18 using several blowing steps B29C49/16 takes precedence
• CPC Class Codes: B29C 49/20 of articles having inserts or reinforcements ; Handling of inserts or reinforcements
• CPC Class Codes: B29C 49/30 having movable moulds or mould parts
• CPC Class Codes: B29C 49/4205 Handling means, e.g. transfer, loading or discharging means handling of inserts or reinforcements B29C49/20; handling of linings or labels B29C49/2408
• CPC Class Codes: B29C 49/42067 Extruded preforms, e.g. providing means for avoiding deformation of the soft preform
• CPC Class Codes: B29C 49/4242 Means for deforming the parison prior to the blowing operation B29C49/08 takes precedence
• CPC Class Codes: B29C 49/42422 : by the preform transporting means
• CPC Class Codes: B29C 49/4802 : with means for locally compressing part(s) of the parison in the main blowing cavity
• CPC Class Codes: B29C 49/4817 : with means for closing off parison ends
• CPC Class Codes: B29C 49/58 : Blowing means
• CPC Class Codes: B29D 22/003 : Containers for packaging, storing or transporting, e.g. bottles, jars, cans, barrels, tanks
• CPC Class Codes: B29L 2031/7172 : Fuel tanks, jerry cans

Abstract

The invention relates to a method for producing a plastic article and a blow molding tool for performing the method. The method comprises extruding an approximately tube-shaped preform, dividing the melt flow within the extrusion head or separating the extrudate exiting or already exited from the extrusion head, such that a preform having an approximately C-shaped cross section is obtained, forming the preform into a hollow part within a multipart blow molding tool using differential pressure, wherein an expansion and partial preforming of the preform first takes place with the blow molding tool partially closed, then in a further step at least one insert is inserted into the interior of the partially preformed article between the not completely closed blow molding tool and through the open side of the preform, and in a further step the blow molding tool is completely closed, wherein the article is completely formed, forming at least one at least partially circumferential pinch-off seam.

Claims

1. A blow molding tool for producing a plastic article, comprising:

at least two blow mold halves each having a cavity that complement one another to form an impression, wherein the at least two blow mold halves are openable and closeable in relation to one another,

wherein at least one blow mold half of the at least two blow mold halves includes a movable mold spacer configured to abut another blow mold half of the at least two blow mold halves, the movable mold spacer comprising a four-sided frame disposed around the cavity and being retractable into and extendable out of a separating plane of the blow mold halves,

wherein at least one of the sides of the frame defines at least a portion of at least one recess in the frame configured to provide an access opening to the cavity when the movable mold spacer abuts the other blow mold half, and

wherein, when the movable mold spacer is retracted, the access opening is fully closeable by the mold halves.

2. The blow molding tool as claimed in claim 1, wherein:

the mold spacer is adapted to a contour of the cavity of the mold half.

3. The blow molding tool as claimed in claim 1, wherein:

the mold spacer is temperature controllable.

4. The blow molding tool as claimed in claim 1, wherein:

the at least two blow mold halves are arranged to provide a closing movement in two stages,

wherein in a first stage of the closing movement the mold spacer is extended, and

wherein in a second stage of the closing movement the mold spacer is retracted.

5. The blow molding tool as claimed in claim 1, wherein:

the at least one side of the frame which defines at least a portion of at least one recess in the frame configured to provide an access opening to the cavity when the movable mold spacer abuts the other blow mold half further defines at least a portion of a plurality of recesses in the frame configured to provide a plurality of access openings to the cavity when the movable mold spacer abuts the other blow mold half.

6. The blow molding tool as claimed in claim 1, wherein:

each blow mold half of the at least two blow mold halves includes a movable mold spacer configured to abut the movable mold spacer of the other blow mold half, each of the movable mold spacers comprising a four-sided frame disposed around the cavity,

wherein at least one of the sides of the frame of each mold spacer defines at least a portion of at least one recess in the frame configured to provide an access opening to the cavity when the movable mold spacer abuts the other blow mold half.

7. The blow molding tool as claimed in claim 6, wherein:

each mold spacer is retractable into and extendable out of a separating plane of the blow mold halves.

8. The blow molding tool as claimed in claim 6, wherein:

each mold spacer is adapted to a contour of the cavity of each mold half, respectively.

9. The blow molding tool as claimed in claim 6, wherein:

each mold spacer is temperature controllable.