Warp sheet splitting device for a drying chamber in a yarn sizing process

In a sizing process for a warp sheet of yarns, a drying chamber has an upper first region, substantially void of a drying medium, and a second region containing the drying medium. A transversable warp splitting device is provided in the chamber which is traversable from the first region, where a plurality of splitting bars can be inserted through the warp sheet so as to split it into sheets of lesser density, to a second region, where the warp sheet is acted upon by the drying medium. A cooling medium is provided between the first and second regions so as to prevent migration of the drying medium from the second region to the first region. The splitting device comprises a carriage driven for movement along a track which extends in a downwardly inclined direction from the first region to the second region.

BACKGROUND OF THE INVENTION 
The present invention relates to the sizing and drying of a warp sheet of 
yarns. More particularly, the invention relates to a warp sheet splitting 
device for splitting the warp sheet of yarns into separate sheets of 
lesser density within a drying chamber. 
In the drying chamber of a solvent sizing apparatus as shown, for example, 
in British Pat. No. 1 502 604, the warp sheet of yarn is split into sheets 
of lesser warp density by inserting tapes which are held apart in a 
splitting area so that splitting bars can be inserted to divide the warp 
sheet into the separate sheets of lesser density. It is difficult to 
ensure that there will be no heated solvent vapour in the splitting area 
with the result that there is danger to the operative when inserting the 
splitting bars to split the warp sheet. 
It is an object of this invention to provide apparatus for and a method of 
drying a warp sheet of yarns in a sizing process which will enable an 
operative to split the warp sheet of yarns into sheets of lesser density 
conveniently and without danger. 
SUMMARY OF THE INVENTION 
These objects are achieved by the provision of apparatus for drying a warp 
sheet of yarns in a sizing apparatus including a drying chamber through 
which the warp sheet of yarns passes so as to be acted upon by a drying 
medium, and a warp sheet splitting device comprising a carriage provided 
with a plurality of splitting bars, the carriage being traversable within 
the drying chamber from a first position, in which the splitting bars are 
inserted through the warp sheet so as to split the warp sheet into sheets 
of lesser density, to a second position, in which the drying medium 
effects a drying action on the split warp sheets. 
Preferably the drying chamber has a first region substantially void of a 
drying medium, and a second region containing the drying medium, the warp 
splitting device comprising a carriage provided with a plurality of 
splitting bars, the carriage being traversable between the first region, 
in which the splitting bars are inserted through the warp sheet so as to 
split the warp sheet into sheets of lesser density whilst in isolation 
from the drying medium, and the second region, in which the drying medium 
effects a drying action on the split warp sheets. 
These objects are also achieved in a sizing process by a method of drying a 
warp sheet of yarns in a drying chamber having a first region, 
substantially void of a drying medium, and a second region, containing a 
drying medium for drying the warp sheet, comprising the steps of inserting 
a plurality of splitting bars through the warp sheet to split it into 
sheets of lesser density in the first region of the chamber, traversing 
the splitting bars into the second region, and forwarding the sheets of 
lesser density through the second region whereby the drying medium effects 
a drying acting thereon.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
With reference to the drawings, the apparatus comprises a size box 1 for 
applying a quantity of solvent based size to a warp sheet. A substantially 
closed drying chamber 2 has upper and lower regions separated by a conduit 
3 containing cooling water, the lower region having means (not shown) for 
projecting and collecting a solvent drying medium. The cooling effect of 
the cooling water in the conduit 3 prevents migration of the solvent 
drying medium from the lower drying region to the upper region which is 
therefore substantially free of drying medium. A warp splitting unit 
within the drying chamber 2 comprises a carriage 4, which extends across 
the width of the machine. The carriage 4 supports a motor 5 for driving a 
shaft 6 which in turn drives through suitable gearing a plurality of warp 
splitting bars 7 thereby to assist in forwarding the warp sheets through 
the drying chamber. The splitting bars 7 extend substantially across the 
width of the machine. The carriage 4 is traversably mounted on a track 
formed by bars 8 inclined downwardly from the upper region to the lower 
region and which are mounted within the chamber at each side thereof. 
Guide rolls 9 run on opposite sides of the inclined bars 8 and support the 
carriage 4 for motion therealong under the control of a conveyor. The 
conveyor comprises two pulleys 10 and a chain 11 at each side of the 
machine for moving the carriage. A motor (not shown) drives a shaft 12 on 
which are mounted two pulleys 10 and thereby turns the chains 11 which are 
bolted to the carriage 4 thus traversing the carriage 4 along the inclined 
bars 8. The motor which drives the conveyor has a braking arrangement 
fitted thereto, so that by stopping the motor and applying the brake, the 
carriage 4 can be stopped in any desired position. The numeral 17 
indicates a divided warp sheet position when the carriage 4 is in the 
upper region of the chamber 2 and numeral 18 indicates the same warp sheet 
when the carriage is in the lower region of the chamber 2. 
In operation when threading up the sizing machine the warp sheet is divided 
into separate sheets of lesser density by inserting tapes therethrough. 
The divided warp sheet is then forwarded into the size box 1 and into the 
dryer 2. The carriage 4 of the warp splitting unit is then traversed up 
the inclined bars 8 (by means of the motor driving the conveyor chain 11) 
to a position as indicated by dotted line 13 at position `B` in the upper 
region of the chamber 2. Side doors 14 provided in each side wall X, Y of 
the machine are opened to allow access to the carriage at the position 
`B`. 
In this position, an end stopping bar 15 is raised to allow splitting bars 
to be manually passed through the opening in the wall `X` between the warp 
sheets and through one of a plurality of apertures in a bearing 16. The 
bar is then pulled back toward the wall `X` to locate the near end in the 
respective aperture in a bearing 17. Each splitting bar carries a gear 71 
at one end thereof whereby, when all the bars are located in the bearings 
16, 17, the gears 71 mesh to form a continuous drive chain whereby the 
bars can be driven via a gear box 61 by the shaft 6. When all the 
splitting bars are so located, the end stopping bar 15 is lowered to the 
position shown in dotted outling `Z` to prevent axial movement of the bars 
7 out of the bearings 16, 17 and the disengagement of the gears 71. 
At this time the doors are closed and the carriage 4 lowered by operation 
of the motor (not shown) to a predetermined level within the lower region 
of the chamber 2. The split warp sheets are then forwarded so as to be 
subjected to a drying operation in the lower region of the chamber by the 
application thereto of a heated solvent vapour. 
Thus the invention overcomes a disadvantage associated with the solvent 
sizing process by enabling the warp sheet to be split into sheets of 
lesser density in a safe and convenient manner.