Patent · US Expired

Method of forming screen packs

US4138303A · kind A · utility

42Cited by
16References
7Claims
0Family size

Inventor

Key dates

Filing dateApr 21, 1977
Grant dateFeb 6, 1979
Priority date
Expiry dateApr 21, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T442/126
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The disclosure concerns a technique for forming screen packs which may be used in filtering foreign matter from an extruded plastic material. Such technique involves initially forming a sandwich array which includes a number of sheets of screening, each sheet of screening having a desired orientation with respect to each other sheet of screening. The sandwich array also includes at least one sheet of thermoplastic material. The sandwich array is heated, in order to cause the thermoplastic material to flow into the openings in the sheets of screening, such that the sandwich array will constitute a unitary structure upon the cooling of the thermoplastic material. Thereafter, at least one screen pack, and preferably several screen packs are formed from such unitary structure, e.g., through the performance of a suitable punching operation on the unitary structure.

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