Patent · US Expired

Apparatus for producing plastic objects with solid sections and hollow sections

US6264455A · kind A · utility

0Cited by
10References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 7, 2000
Grant dateJul 24, 2001
Priority date
Expiry dateJul 7, 2020

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C45/1711
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A method and an apparatus are disclosed for producing plastic objects with solid regions and hollow regions. The method has the following steps: a) blocking off a part of the cavity (2) of a molding tool (1), so that little or no plastic melt can reach the blocked-off region (8); b) injecting plastic melt into the unblocked region (9) of the cavity (2) of the molding tool (1); c) releasing the blockage, so that plastic melt can reach the previously blocked-off region (8) of the cavity (2); d) injecting a pressurized gas into the melt by means of at least one fluid injection nozzle (7), so that the melt injected into the molding tool is distributed into the desired regions of the cavity (2) while forming a hollow space and is pressed against the cavity walls of the molding tool (1); e) allowing the molded part (6) to cool; f) relieving the cavity (2) of the pressure of the pressurized fluid; and g) demolding the molded part. The advantage achieved thereby is that solid regions and hollow regions are formed in the molded part in a predetermined manner.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.