Method for producing a moulded body that encloses a cavity by welding two partial bodies, and die for welding two partial bodies

Patent metadata

Field	Value
Publication number	US-12384118-B2
Application number	US-202017430749-A
Country	US
Kind code	B2
Filing date	Feb 4, 2020
Priority date	Feb 14, 2019
Publication date	Aug 12, 2025
Grant date	Aug 12, 2025

Abstract

Described herein is a process for producing a molded body which encloses a cavity, by welding two partial bodies. Also described herein is a die with which the process of producing the molded body can be carried out. Also described herein is a molded body which can be obtained by the process.

First claim

The invention claimed is:

1. A process for producing a molded body which encloses a cavity, by welding of two partial bodies ( 1 a , 1 b ), comprising the steps a), b), c), d) and e):
a) providing a first partial body ( 1 a ), wherein the first partial body ( 1 a ) comprises a continuous first welding web ( 2 a ) with a course,
b) providing a die ( 5 ) which comprises a continuous first channel ( 7 a ) with a course, wherein the course of the first channel ( 7 a ) corresponds to the course of the first welding web ( 2 a ), wherein the first channel ( 7 a ) comprises first means ( 11 a ) for introducing hot gas, and wherein the die ( 5 ) comprises a first means ( 30 a ) for an active regulation of pressure,
c) positioning the first welding web ( 2 a ) of the first partial body ( 1 a ) in a region of the first channel ( 7 a ) of the die ( 5 ), whereupon a first internal space ( 20 a ) is formed between the first partial body ( 1 a ) of the two partial bodies and the die ( 5 ),
d) introducing hot gas through the first channel ( 7 a ), with resultant melting of the first welding web ( 2 a ) of the first partial body ( 1 a ), and active regulation of a pressure in the first internal space ( 20 a ) by the first means ( 30 a ) and
e) bringing the molten first welding web ( 2 a ) of the first partial body ( 1 a ) into contact with a second welding web ( 2 b ) with a course of a second partial body ( 1 b ), wherein the course of the second welding web ( 2 b ) corresponds to the course of the first welding web ( 2 a ),
wherein gas is discharged from the first internal space ( 20 a ) and/or a second internal space ( 20 b ) by the first means ( 30 a ) and/or a second means ( 30 b ) for an active regulation of pressure.

2. The process according to claim 1 , wherein the first means ( 30 a ) is positioned in a region that is enclosed by the course of the first channel ( 7 a ).

3. The process according to claim 1 , wherein step a) additionally comprises providing the second partial body ( 1 b ), wherein the second partial body ( 1 b ) comprises the second welding web ( 2 b ).

4. The process according to claim 1 , wherein the die ( 5 ) provided in step b) comprises a first side ( 6 a ) and a second side ( 6 b ), wherein the first channel ( 7 a ) is arranged on the first side ( 6 a ) and wherein a continuous second channel ( 7 b ) is arranged on the second side ( 6 b ), wherein the second channel ( 7 b ) comprises a means ( 11 b ) for introducing hot gas and wherein the second means ( 30 b ) for an active regulation of pressure is arranged on the second side ( 6 b ).

5. The process according to claim 1 , wherein step c) additionally comprises positioning the second welding web ( 2 b ) of the second partial body ( 1 b ) in a region of the second channel ( 7 b ) of the die ( 5 ), whereupon a second internal space ( 20 b ) is formed between the second partial body ( 1 b ) and the die ( 5 ), and step d) additionally comprises introducing hot gas through the second channel ( 7 b ), with resulting melting of the second welding web ( 2 b ) of the second partial body ( 1 b ), and an active regulation of a pressure in the second internal space ( 20 b ) by the second means ( 30 b ).

6. The process according to claim 1 , wherein gas is introduced into the first internal space ( 20 a ) and/or the second internal space ( 20 b ) by the first means ( 30 a ) and/or the second means ( 30 b ).

7. The process according to claim 1 , wherein, in step c), the first welding web ( 2 a ) is positioned in a region of the first channel ( 7 a ), wherein a first distance (Xa) between a die-( 5 ) facing end face of the first welding web ( 2 a ) and a first channel-entry plane ( 14 a ) is in a range of >0 to 3 mm outside of the first channel ( 7 a ) or in a range of 0 to 10 mm inside of the first channel ( 7 a ).

8. The process according to claim 1 , wherein, in step c), the second welding web ( 2 b ) is positioned in a region of a second channel ( 7 b ), wherein a second distance (Xb) between a die-( 5 ) facing end face of the second welding web ( 2 b ) and a second channel-entry plane ( 14 b ) is in a range of >0 to 3 mm outside of the second channel ( 7 b ) or in a range of 0 to 10 mm inside of the second channel ( 7 b ).

9. The process according to claim 1 , wherein the first means ( 30 a ) comprised in the die ( 5 ) is positioned in the first partial body ( 1 a ) and/or the second means ( 30 b ) comprised in the die ( 5 ) is positioned in the second partial body ( 1 b ).

Assignees

• Basf Se

Inventors

• Mochev Stefan
• Endemann Ulrich

Classifications

• B29L2022/00

  Hollow articles (tubular articles B29L2023/00; pneumatic tyres B29L2030/00) · CPC title

• B29C66/80

  General aspects of machine operations or constructions and parts thereof · CPC title

• B29C66/7392

  characterised by the material of at least one of the parts being a thermoplastic · CPC title

• B29C66/54 Primary

  Joining several hollow-preforms, e.g. half-shells, to form hollow articles, e.g. for making balls, containers; Joining several hollow-preforms, e.g. half-cylinders, to form tubular articles · CPC title

• B29C66/43

  Joining a relatively small portion of the surface of said articles (B29C66/45 takes precedence) · CPC title