Note: Descriptions are shown in the official language in which they were submitted.
This invention relates to the handling of an array of fibers,
splitting the array of fibers into bundles and collecting the
bundles.
In known fiber collecting operations fibers in an array are
passed into contact with a surface, which can be an applicator
surface, and are then collected, usually by being wound into a
package on a winder. A comb-like splitter is often inserted into
the array of fibers just below the applicator surface to divide
the fibers into bundles and to produce a split-strand package.
The splitter physically separates the array of fibers into
bundles of fibers.
Heretofore the insertion of the splitter into the array has
been a time-consuming task, requiring a manual separation of the -
array into bundles. In known apparatus the fibers of the array
generally do not assu~e a uniform alignment and are continually
"dancing" i.e. moving laterally relative to each other. This lack
- of uniformity of alignment of the fibers makes separation of the
array into bundles even more difficult and it is especially
difficult to obtain bundles with approximately equal numbers of
fibers.
The present invention seeks to provide a method and appara-
tus enabling this difficulty to be avoided or at least reduced.
According to one aspect of this invention there is provided
a method of collecting an arra~ of fibers comprising passing said
array of said fibers in contact with a contact surface, and con-
tact producing a first frictional drag force on said fibers; split-
ting said array into a plurality o bundles of fibers; modifying
the drag force between said array of fibers and said contact
surface to produce a second frictional drag force; and collecting
said bundles of fibers. Preferably said first frictional drag
force is greater than said second frictional drag force.
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Accordin~ to another aspect of this invention there is
provided apparatus for collecting an array of fibers comprising
a contact surface arranged to be contacted by said array of
fibers to produce a frictional drag force on said fibers; splitter
means for dividing said array into a plurality of bundles of
fibers; means for modifying said frictional drag force; and means
for collecting said bundles of fibers. Preferably said contact
surface is an applicator surface.
An increase in the frictional drag force applied to the
fibers as they contact the applicator surface increases the
tension of the fibers in the array and reduces the "dancing"
effect referred to above, makes insertion of the splitter easier,
and allows the array to be divided into bundles o nearly equal
size. The fibers, under the influence of the increased drag
force have a tendency to assume the alignment of the source of
the array of fibers. For example, fibers pulled from a fiber-
forming bushing will, under increased drag force, be more disposed
to assume an alignment at the contact surface which corresponds to
the alignment of fibers at the bushing.
In its most preferred embodiment the contact surface is a
rotating surface and the frictional drag force is modified by
changing the speed of rotation of the surface. In alternative
embodiments the frictional drag force is modified by changing the ;
amount of a lubricant applied to the contact surface, or by
changing the area of contact between the array of fibers and the
contact surface.
The method and apparatus of this invention are particularly
suitable for the handling of an array of glass fibers, especially
glass fibers drawn from a fiber~forming bushing.
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The invention will be further understood from -the follow-
ing description by way of example oE embodiments thereof with
reference to the accompanying drawings, in which:
Figure 1 is a front elevation view and
Figure 2 is a side elevation view of a fiber-forming
bushing and fiber array handling apparatus, the two figures
illustrating different embodiments Qf this invention, and
Figure 3 is a plan view o a splitter shown in Figures
1 and 2.
Referring to the drawings, there is shown a bushing 10
comprising a chamber for holding glass mass 12. The chamber has
orifices 14 through which glass is emitted and attenuated into
fibers 16 in the form of an array.
The array of fibers is passed in contact with a contact
surface 18, thereby creating a frictional drag force on the
fibers. Below the contact surface the fibers are contacted by
a gathering member 20 which is suitable for gathering the
fibers into a strand. The strand is collected on a rotating
collet 22 of a conventional winder 24.
In order to divide thP array of fibers into bundles of
fibers, a splitter 26 is inserted into the array. The splitter
can be inserted manually. The comb-like splitter, shown in
Figure 3, has projections to maintain separation between fiher ~ -
bundles. It is usually desirable to divide the array evenly to
obtain bundles containing substantially equal numbers of fibers.
Subsequent to the splitting, the bundles of fibers can be com-
bined to form a single strand, as shown in Fi~ures 1 and 2, or
they can be collected while the separation between bundles is `
maintained.
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One method which can be used to modify the drag force
exerted by the contact surface from a first drag force to a
second drag force is to make the contact surface 18 rotatable
and to rotate the contact surface at different speeds. For
example, in a typical fiber forming and collecting operation,
a rotating size applicator surface is utilized to contact the
fibers and apply a size. By changing the speed of rotation
of the applicator surface, the drag force on the fibers is
modified. The rotation of the applicator surface can be
10 accomplished by means of a variable speed motor 30 as shown in ~ '
Figure 1.
In another embodiment of this invention the frictional
drag force applied to the fibers by the contact surface is mod- ;
ified by changing the amount of a lubricant applied to the ~`~
contact surface. An increase in the amount of lubricant decreases ~,~
the drag force on the fibers. For example, as shown in Figure 2,
lubricant 32 flows from a reservoir 34 through a conduit 36 and
onto the contact surface 18. A valve 38 controls the amount of
lubricant deposited. In a typical fiber forming and collecting
20 operation, a size is applied to the fibers at the contact sur- ~
face, and the size acts as a lubricant. - ;
It is to be understood that the contact surface can be a
rotatable size applicator of the type in which the rotating sur-
face contacts a size reservoir to become coated with a size and
in which increasing the speed of rotation results in an increase
in the amount of size coating the applicator surface. Thus, the
drag force from such an applicator can be reduced by increasing
the rotational speed of the applicator; this results in an
increase in the amount of size coating the applicator surface.
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In another embodiment of this invention, the frictional
force applied to the fibers by the contact surface is modified
by changing the amount of con-tact between the fibers and the
contact surface. If the contact surface is curved, as shown
in Figure 2, this can be accomplished by increasing the angle
of wrap of the fibers around the curved surface. For example,
movement of the gathering member 20 along the path indicated
by the arrows in Figure 2 has the ef*ect of modifying the wrap
angle at the contact surface. As the gathering member in
Figure 2 is moved to the right, the wrap angle increases,
thereby increasing the drag force and producing a more uniform
; alignment of fibers in the array. It is also possible for the
contact surface to be moved to change the amount of contact
between the fibers and the contact surface.
It will be evident that various other modifications can
be made without departing from the scope of the invention as
defined in the claims.
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