Apparatus for forming polymer, comprising polymer backflow prevention portion

Patent metadata

Field	Value
Publication number	US-2016185020-A1
Application number	US-201314650392-A
Country	US
Kind code	A1
Filing date	Dec 12, 2013
Priority date	Dec 12, 2012
Publication date	Jun 30, 2016
Grant date	—

Abstract

The present invention provides an apparatus for forming a polymer, comprising: a chamber having a predetermined pressure and storing a molten polymer resin; a foaming agent injection portion connected to the chamber and supplying a foaming agent, which is supplied from the outside, into the chamber by forming a pressure equal to or higher than the pressure inside the chamber; and a polymer backflow prevention portion provided at the foaming agent injection portion, and through which the supplied foaming agent passes so as to increase a contact surface area with the polymer resin, thereby preventing the backflow of the polymer resin.

First claim

1 . A polymer forming apparatus comprising:
a chamber having a predetermined pressure and storing a molten polymer resin; a foaming agent injector connected to the chamber and supplying a foaming agent received from outside into the chamber by a pressure higher than or equal to a pressure inside the chamber; and a polymer backflow prevention unit provided to the foaming agent injector and allowing the supplied foaming agent to pass therethrough while preventing the polymer resin from flowing back by increasing a contact surface area with the polymer resin.

2 . The polymer forming apparatus according to claim 1 , wherein the foaming agent injector comprises:
a foaming agent injection pipe which comprises an inlet channel forming an inlet for a foaming agent, an outlet channel forming an outlet for the foaming agent, and a middle channel connecting the inlet channel to the outlet channel and having a smaller inner diameter than the inlet channel and the outlet channel; and an elastic shut-off unit elastically disposed inside the outlet channel to be placed at an outlet side of the middle channel, and opening or closing the middle channel according to supplying pressure of the foaming agent, wherein the polymer backflow prevention unit is disposed at an end of the outlet channel, and wherein the elastic shut-off unit is supported by the polymer backflow prevention unit.

3 . The polymer forming apparatus according to claim 2 , wherein
the outlet channel is connected to a lower end of the middle channel, and has an inclined channel having an inner diameter gradually increasing downward from the lower end of the middle channel; and the elastic shut-off unit comprises a shut-off ball disposed in the inclined channel and opening or closing the inclined channel, and an elastic member elastically and mutually supporting the shut-off ball and the polymer backflow prevention unit.

4 . The polymer forming apparatus according to claim 3 , wherein the polymer backflow prevention unit comprises:
a backflow-prevention plate body disposed at the end of the outlet channel and supporting an end of the elastic member; and a plurality of backflow prevention holes formed in the backflow-prevention plate body.

5 . The polymer forming apparatus according to claim 4 , wherein the backflow prevention holes have a polygonal shape.

6 . The polymer forming apparatus according to claim 4 , wherein the backflow prevention holes are tapered in a direction of supplying the foaming agent.

7 . The polymer forming apparatus according to claim 4 , wherein the backflow prevention holes comprise a plurality of protrusions formed on an inner circumference thereof.

8 . The polymer forming apparatus according to claim 4 , wherein the backflow-prevention plate body is detachably coupled to the end of the outlet channel.

9 . The polymer forming apparatus according to claim 4 , wherein the backflow prevention plate is inclined from an edge toward a center in the direction of supplying the foaming agent.

Assignees

• Lg Hausys Ltd

Inventors

• Jeon Byung Joo
• Lee Eung Kee
• Choi Chul June
• Kim Myeong Hee
• Kim Ji Mun
• Ji Seung Wook

Classifications

• B29C44/3446 Primary

  Feeding the blowing agent · CPC title

• B29C2945/76006

  Pressure · CPC title

• B29C45/1816

  Feeding auxiliary material, e.g. colouring material · CPC title

• B29C2945/76775

  Fluids · CPC title

• B29C44/35

  Component parts; Details or accessories · CPC title