Glass fiber forming apparatus

Claim 2

Glass fiber producing apparatus comprising: a hollow rotor (2) mounted for rotation about an axis (1) and having a plurality of radially directed orifices (4) in a side wall (5) thereof from which a flange (6) extends towards said axis (1), said rotor (2) being arranged, when supplied with molten glass (9), to rotate and eject filaments of glass from said orifices (4); and a blast burner (7) arranged to produce a flame jet (14) adjacent said orifices (4) externally of the rotor (2) to cause the glass ejected therefrom to form secondary filaments, characterized in that the flame jet (14) contacts said side wall (5) for heating thereof in use of the apparatus, only over a region axially spaced from said flange (6), and in that a further burner (15) is provided at a position radially inward of said flange (6) and is arranged to produce a further flame (16) directed generally away from said axis (1) and over and parallel to at least one surface of said flange whereby the region (17) where said flange (6) meets said side wall (5) is heated, in use of the apparatus, sufficiently to maintain ejection of glass from orifices (4) of the rotor (2) in said region.

Claim 3

Apparatus according to claim 1 character- ized in that said flame jet (14) is formed in use of the apparatus with an inner conical region (12) and an outer expanding region (13).

Claim 4

Apparatus according to claim 2 character- ized in that said blast burner (7) is so positioned and directed that when in use only said expanding region (13) contacts said side wall (5).

Claim 5

Apparatus according to any one of claims 1 to 3 characterized in that said side wall (5) is cylindrical.

Claim 6

Apparatus according to any one of claims 1 to 4 characterized in that said further burner (15) is arranged to produce said further flame (16) entirely outside said rotor (2).

Claim 7

Apparatus according to any one of claims 1 to 4 characterized in that said further burner (15) is arranged to produce said further flame (16) both inside and outside said rotor (2).

Claim 8

Apparatus according to any one of claims 1. to 6 characterized in that said further burner (15) is arranged to produce said further flame (16) of such size as to contact said region (17) where said flange (6) meets said side wall (5).

Claim 9

Glass fiber forming apparatus comprising: a hollow-cylindrical rotatable rotor (2) having a base (3), a surrounding wall (5) with a plurality of molten glass ejecting orifices (4), and an upper annular flange (6) extending inwardly from the upper edge of said surrounding wall (5); and an attenuating blast burner (7) having jet flame orifices (11) adapted to produce jet flame (14) to attenuate primary filaments formed at tips of transition cones of molten glass ejected from said rotor (2) into secondary filaments, characterized in that said jet flame orifices (11) in said attenuating blast burner (7) are so positioned that only an outer region (13) of each jet flame (14), the speed of which region (13) is sufficiently low not to disrupt said transition cones of molten glass, is in contact with a lower portion of the outer surface of said surrounding wall (5), a heating burner (15) is disposed within said upper annular flange, and is arranged to project a flame (16) in a direction which is aligned with said upper annular flange (6) and is in parallel with the surface thereof, said flame (16) from said heating burner (15) heating said rotor (2) in such manner that said flame (16) passes along the upper surface, or the upper and lower surfaces, of said upper annular flange (6) and heat is transmitted at least to a corner (17) where said upper annular flange (6) meets said surrounding wall (5).

Claim 10

Glass fiber forming apparatus comprising: a hollow-cylindrical rotatable rotor (2) having a base (3), a surrounding wall (5) with a plurality of molten glass ejecting orifices (4), and an upper annular flange (6) extending inwardly from the upper edge of said surrounding wall (5); and an attenuating blast burner (7) having jet flame orifices (11) adapted to produce jet flame (14) to attenuate primary filaments formed at tips of transition cones of molten glass ejected from said rotor (2) into secondary filaments, characterized in that said jet flame orifices (11) in said attenuating blast burner (7) are so positioned that only an outer region (13) of each jet flame (14), the speed of which region (13) is sufficiently low not to disrupt said transition cones of molten glass, is in contact with a lower portion of the outer surface of said surrounding wall (5), a heating burner (15) is disposed within said upper annular flange, and is arranged to project a flame (16) in a direction which is aligned with said upper annular flange (6) and is in parallel with the surface thereof, said flame (16) from said heating burner (15) heating said rotor (2) in such manner that said flame (16) passes along the upper surface, or the upper and lower surfaces, of said upper annular flange (6) and heat is transmitted at least to a corner (17) where said upper annular flange (6) meets said surrounding wall (5).