Improvements in Apparatus for Oxidising Indigo-dyed Fabrics.
Year: 1895

page_text: Date of Application, 30th July, 1895-Accepted, 31st Aug., 1895
COMPLETE SPECIFICATION.
Improvements in Apparatus for Oxidising Indigo-dyed Fabrics.
I, DUNCAN STEWART, of London Road Iron Works, in the County of Glasgow,
North Britain Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement, that is to say:—
My said invention has for its object the oxidising of indigo-dyed fabrics in a
superior and uniform manner by means of improved apparatus of which an example
is delineated upon an accompanying sheet of drawings hereinafter referred to.
The drawing is a side elevation showing parts of dyeing vats, A, B, which are
two of a series of two or more through which the fabric, C, to be dyed is to be
passed.
On leaving each vat such as A, the fabric, C, passes as usual through between a
pair of driven squeezing rollers, D, which express superabundant dyeing liquid;
and the fabric proceeds through the oxidising apparatus which occupies the space
between one vat, A, and the next, B. For oxidising the dye on the fabric, C, the
fabric is as usual exposed to the action of the atmosphere, but such action is
rendered very regular and uniform by the use of my improved apparatus which is
continuous in its operation, whilst exposing every part of the fabric for the same
length of time.
The apparatus comprises a framing consisting of two pairs of standards or
pillars, E, which are connected by horizontal frame bars, F, (the pillars and bar
shown in the drawing preventing from being seen similar pillars and a bar, which
are on the further side). The framing is provided with bearings for four transverse
horizontal spindles or small shafts, G, which have fixed on them near their ends
and just within their bearings, pulleys, H, round which are distended two endless
chains, J. Rods, K, are fixed transversely between the chains, J, and their ends
may coincide with or form the joints of the chain links, the combination forming
an endless series of rods.
The pairs of pillars, E, support at their upper ends, transverse horizontal guide
rollers, L, M, and the fabric, C, from the vat, A, passes up to one guide roller, L,
and thence downwards to the rods, K, near which the fabric passes through a
guide, N. The rods, K, are at the upper part of their course being slowly moved
in the direction of the arrow, by means of a wormwheel, P, on one of the spindles, G,
driven by a worm, Q, on a longitudinal power shaft, R, which also, by bevil
gearing, drives the squeezing rollers, D. The rates of motion of the rods, K, and
of the fabric, C, are so proportioned that whilst one rod is travelling a distance
equal to that between it and the next, enough of the fabric descends between the
two rods to form a loop, and as the rods progress a series of such loops are formed
depending as shown from the rods. On each rod, K, about reaching the forward
end of the upper horizontal part of the course of the rods, the fabric, C, passes up
to and over the guide roller, M, at the top of the second pair of pillars, E, being
drawn down thence into the next vat, B.
With the apparatus described a large quantity of fabric is exposed to the
oxidising action of the atmosphere and every part of it traverses precisely the same
course and is exposed for the same length of time.
If desired two endless series of rods (K) may be arranged one over the other
upon the same framing, for simultaneously oxidising two pieces of fabric (C) drawn
from one vat, or drawn from separate vats.

page_text: For maintaining the proper distension of the endless series of rods, K, they may
at the lower corners, pass round rollers held in adjustable bearings, S, and the
endless chains, J, may be guided horizontally along the upper part of their course
by guide flanges formed on the inner sides of the frame bars, F.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is.
1. The combination of parts constituting my improved apparatus for oxidising
indigo-dyed fabrics, substantially as herein before described.
2. In apparatus for oxidising indigo-dyed fabrics, combining an endless series of
rods, moved forwards along an upper part of their course and returning partly
along a lower part of their course, with means for guiding the fabric and moving it
at a suitable rate relatively to the movement of the rods, in a manner to form
depending loops between the rods substantially as and for the purposes herein before
described.
Dated this Twenty-ninth day of July 1895.
EDMUND HUNT,
Applicant's Agent.