Patent · US Expired

Apparatus for producing a body of porous thermoplastic material

US4067672A · kind A · utility

2Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 20, 1975
Grant dateJan 10, 1978
Priority date
Expiry dateNov 20, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S264/12
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The invention relates to an apparatus for continuous production of a strand of porous thermoplastic material from preferably pre-expanded granules of said material containing an expanding agent. The apparatus comprises an elongated rectangular channel, two opposite sides of which are formed by the horizontal parts facing one another of two superimposed endless belts moving in a closed path between turning rollers. The granules are introduced through the open intake end of said channel and are expanded to final size and sintered together to a porous coherent strand by means of steam fed between the horizontal belt parts facing one another. The steam and the granules are fed into the channel through individual ducts which are separated from one another and connected to the intake end portion of the channel. Usually, a plurality of granule feeding ducts and a plurality of steam supplying ducts are attached to the intake end portion formed as a box of particular shape. Some specific grouping of the ducts connected to said box has proved to render excellent results in uniform distribution of the granules and even heating to sintering temperature.

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