Patent · US Expired

Zirconia induction furnace

US4450333A · kind A · utility

24Cited by
10References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 28, 1982
Grant dateMay 22, 1984
Priority date
Expiry dateMay 28, 2002

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03B2205/70
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A high frequency induction furnace (10) for reflowing a portion of a lightguide preform (44) in order to draw a fiber (52) therefrom. The furnace (10) has a centrally located tubular susceptor (34) therein having a thin coating of the preform material (e.g., silica) on at least a portion of the inside surface thereof. A cylinder (62) is positioned in concentric, spaced relation about the susceptor (34) and is surrounded by an insulating grain (36). A high frequency coil (38) is energized to couple its electromagnetic field to the susceptor (34) to heat and reflow a portion of the preform (44) in order to draw the fiber (52) therefrom. The thin coating prevents contaminating particulates from migrating from small cracks in the inside surface of the susceptor (34) onto the preform (44) while the cylinder (62) prevents small particulate emanating from the insulating grain (36) from being drawn through larger cracks in the susceptor and onto the preform and/or the fiber 52.

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