Rotary fiber forming spinner

A spinner for the production of molten glass fibers is disclosed. The spinner is adapted with a plurality of projections affixed to the spinner bottom and extending inwardly of the spinner. The projections are intended to inhibit inward flow towards the spinner support and aid wetting of the inner bottom surface of the spinner.

This invention pertains to a rotary fiber forming spinner. 
In one of its more specific aspects, this invention relates to an improved 
spinner for the production of glass fibers by the rotary process. 
The production of glass fibers by means of the rotary process is well 
known. In general, molten glass is fed into a spinner which revolves at 
high speeds. The spinner has a solid lower surface and a circumferential 
wall containing a multiplicity of apertures. The glass, which enters near 
the center of the spinner is thrown by centrifugal force through the 
apertures of the circumferential wall in the form of small diameter 
fibers. These fibers are collected on a collecting surface as a mat which 
receives subsequent treatment depending upon the nature of the product to 
be produced therefrom. 
The molten glass introduced into the spinner can act in various ways due to 
its composition and the temperature conditions under which it is 
introduced. 
A problem encountered upon introduction is that the glass stream does not 
quickly wet the inner bottom surface of the spinner. One result 
encountered is that the glass stream wraps around the rotating spinner 
support, effecting an interruption in the issue of glass through the 
circumferential wall. Another result encountered is that the glass fails 
to uniformly wet the inner bottom surface of the spinner with the result 
that excessive vibrations of the high speed spinner occur. These 
vibrations lead to the ultimate failure of the spinner. A third result 
encountered is the misalignment of the glass stream with the introductory 
conduit which occasions either the interruption of the issue of glass or 
the excessive vibration already mentioned. The apparatus of this invention 
is directed towards the solution of the underlying problem. 
STATEMENT OF THE INVENTION 
According to this invention there is provided a spinner comprising an 
apertured circumferential wall and a bottom wall, the bottom wall being 
adapted with a plurality of inwardly-extending projections. 
Any inward projection which aids wetting of the spinner inner bottom 
surface and acts to form a barrier to the inward flow of glass away from 
the outer circumferential wall and which creates a flow path extending 
outwardly from the glass introductory locus is within the scope of this 
invention. 
In one of its embodiments, the inwardly-extending projections define a 
series of convolutions extending outwardly from the center of the spinner 
to the outer wall. 
In another of its embodiments, the inwardly-extending projections define a 
plurality of circular rows of discontinuous projections, the projections 
of any one row alternately spaced in relation to the projections of the 
next adjacent row. 
In another of its embodiments, the inwardly-extending projections define a 
series of adjacent flow paths opening from the locus at which glass is 
introduced into the spinner, the segments increasing in width as they 
approach the circumferential wall of the spinner. 
In another of its embodiments, the inwardly-extending projections impart a 
uniform random irregularity to the inner bottom surface of the spinner.

Referring now to FIGS. 1 and 2, there is shown spinner 10 having upper wall 
11, apertured circumferential wall 12, and bottom wall 13. The spinner 
will be affixed to a member entering the spinner through port 14 and 
attached to support means 15. Glass introduction will be made by conduit 
means, not shown, through port 14, at approximately locus 16. 
Referring now to FIG. 3, there is shown positioned on bottom wall 13 a 
series of inwardly-extending projections 17 which define a series of 
convolute paths 18 extending outwardly from approximately the center of 
the spinner to the outer wall. These projections are positioned such that 
their convex edge is the leading edge upon rotation. Any number of paths 
can be employed. 
Referring now to FIG. 4, there is shown positioned on the bottom wall 13 a 
series of intermittently spaced protrusions 20 arranged circumferentially 
with respect to support means 15. These projections are arranged in 
circumferential rows 21 such that the projections in any one row are 
placed opposite an opening 22 between the projections of the next adjacent 
rows. Any number of rows of projections can be employed. 
Referring now to FIG. 5, there is shown positioned on the bottom wall 13 a 
series of projections 30 which form a plurality of paths 31 therebetween. 
These projections are in the form of truncated pyramids with outwardly 
curved bases adjacent the spinner wall and occupy a sufficient portion of 
the area of the bottom wall so as to significantly reduce the flow areas 
provided by the paths. In this manner, the flow velocity of the glass to 
the circumferential wall is substantially increased. 
In these first three instances, the extent to which the projections rise 
above the bottom wall can be any reasonable height. In all instances, it 
is desired to aid wetting of the spinner inner bottom surface and to 
create flow channels. Generally, a projection height of from about 0.05 
inch to about 0.50 inch is adequate. 
Referring now to FIG. 6, there is shown positioned on the bottom wall 13 a 
uniform distribution of irregularities 40 creating a random surface 
roughness. In this instance it is desired to directly accelerate wetting 
of the inner bottom surface of the spinner. Specifically, a roughness 
greater than that imparted by standard sand casting is necessary, and a 
roughness of from about 2000 microinches to 4000 microinches arithmetical 
average deviation from the mean surface as measured by a Profilometer or 
Brush Surface Analyzer is generally adequate. 
The number of projections which are employed will be dependent upon the 
distribution of the glass as it issues through the circumferential wall. 
In no instance will the number and positioning of the projections be such 
that glass issuance through the circumferential wall is unevenly 
distributed among the apertures. Similarly, in no instance will the number 
and positioning of the projections be such that the flow through the 
apertures is impeded to the extent that spinner capacity becomes less than 
that attainable in the absence of such projections. 
It will be evident from the foregoing that various modifications can be 
made to the method of this invention. Such, however, are considered within 
the scope of this invention.