IMPROVEMENTS IN HAWKING MACHINES FOR INDIGO DYEING
Year: 1886

page_text: I, JAMES COULTER of Bank-foot Foundry, Batley, Yorkshire, Machine Maker
do hereby declare the nature of my invention for "IMPROVEMENTS IN HAWKING
MACHINES FOR INDIGO DYEING" to be as follows:-
My invention has reference to a certain class of machine for indigo dyeing, and
has special reference to prior Letters Patent granted to Exley Woodcock and John
William Woodcock bearing date the 19th of March 1877 No. 1096.
In this machine nipping rollers are employed rotating in the dye liquor and
between which the fabric passes but as the said fabric adheres to the rollers certain
fixed scrapers are placed in contact with the nipping rollers so as to remove the
fabric, and prevent its being carried around the rollers.
In the practical working of these machines I have found that these fixed scrapers
are imperfect in their action, and that as the point of contact with the rollers is
below their axis, the scrapers have a tendency for and frequently do fall away from
the said rollers.
My improvements consist in placing these scrapers upon a pin or stud, so that
they can move thereon, and I arrange that the point of contact with the rollers is
above the centre; and I also arrange that the point of each scraper shall rest or
bear with its full weight upon the surface of the rollers whereby the tendency to
fall away therefrom is rendered impossible.
Practically it is better for the cloth to leave the nipping rollers before it reaches
the scrapers, as they are liable to damage the piece, therefore by placing the edge
of the scraper above the centre of the roller, the cloth after getting to the centre
has a tendency to rise to the surface of the liquid and away from the scrapers by
the buoyancy of the liquor, and so leave the roller, consequently there are fewer
chances of the cloth being damaged.
Secondly. In this class of machine one of the nipping rollers runs in stationary
bearings, but the other nipping roller runs in yielding bearings, so that when any
irregularity in the thickness of the fabric is passing between the said rollers the
bearings of the yielding nipping roller will give way, but as soon as the irregularity
has passed through; a strong spiral spring forces the two rollers together again.
2

page_text: Heretofore the yielding roller has been so placed that when the fabric got fast
or drawn tight it would draw the yielding nipping roller away from the other
roller and would hold the rollers apart until the fabric is put right or released,
consequently the fabric would be stationary whilst the rollers were revolving;
whereby the piece would be damaged.
To remedy this I reverse the position of the nipping rollers, and so arrange them
that the fabric will pull against the nipping roller running in the stationary bearings
by which means the tightly drawn fabric cannot separate the said rollers as is now
the case and the nip on the cloth will be always the same.

page_text: Onge yo
I, JAMES COULTER, of Bankfoot Foundry, Batley, Yorkshire, Machine Maker,
do hereby declare the nature of my invention for "IMPROVEMENTS IN HAWKING
MACHINES FOR INDIGO DYEING," and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement :-
My invention has reference to a certain class of machine for indigo dyeing and
has special reference to prior Letters Patent granted to Exley Woodcock and John
William Woodcock, bearing date the 19th of March 1877 No. 1096.
In this machine nipping rollers are employed rotating in the dye liquor, between
which the fabric passes, but as the said fabric is wet with dye liquor it adheres to
the rollers, to avoid which, certain fixed scrapers are placed in contact with the
nipping rollers so as to remove the fabric, and prevent its being carried around the
rollers.
In the practical working of these machines I have found that these fixed scrapers
are imperfect in their action, as the point of contact with the rollers is below their
axis, consequently the scrapers have a tendency for, and frequently do fall away
from contact with the said rollers.
My improvements consist in hinging these scrapers upon a pin or stud, so that
they can move thereon, and I arrange that the point of contact with the rollers
is above the centre; whereby the tendency to fall away therefrom is rendered
impossible.
In order that my invention may be better understood I herein give reference to
the accompanying sheets of drawings wherein Fig. 1 is elevation and Fig. 2 section
of that part of a hawking machine for dyeing fabrics to which my improvements
apply. A and B are the nipping rollers, the latter of which is driven positively by
spur gearing a, b, c and d, whilst the roller A is driven by gear wheels from the
opposite side of machine. These rollers are immersed in the dye liquor and the
fabric to be dyed passes through the liquor and between the rollers. O and D are
scrapers capable of oscillating when required upon the pins or hinge e, the lower
points of these scrapers are in contact with the surface of the rollers above the
centre of their axis, and they can be made to bear with more or less pressure upon
the rollers by means of screws operated by the thumb screws E. The piece to be
squeezed enters between the rollers at the point F, and so long as the piece does
not stick or adhere to the surface of the rollers, the scrapers C and D are of no
use, but as the said piece does frequently stick to the rollers, the scrapers C and D
will remove the piece therefrom and cause it to drop into the liquor again so as to
continue its passage through the machine.
Scrapers are not new but they have hitherto been rigid and placed below the
centre of each nipping roller, and this was an objection, because practically it is
better for the cloth to leave the nipping rollers before it reaches the scrapers as
they are liable to damage the piece, therefore by employing yielding scrapers and
placing the edge of the scrapers above the centre of the roller instead of below as
hitherto, the cloth after getting to the centre has a tendency to rise to the surface
of the liquid and away from the scrapers by the buoyancy of the liquor, and so

page_text: leave the roller without the aid of scrapers, consequently when this happens there
are fewer chances of the cloth reaching the scrapers and being damaged thereby.
Secondly. In this class of machine one of the nipping rollers runs in stationary
bearings, but the other nipping roller runs in yielding bearings, so that when any
irregularity in the thickness of the fabric is passing between the said rollers, the
bearings of the yielding nipping roller will give way, but as soon as the irregularity
has passed through the said rollers a strong spiral spring is employed to force the
two rollers together again.
Heretofore the yielding roller has been so placed in the machine that when the
fabric got fast or drawn tight it would draw the yielding nipping roller away from
the other roller and would hold the rollers apart until the fabric was put right or
released, consequently the rollers would cease to nip the fabric which would remain
stationary whilst the rollers were revolving, whereby the piece would be damaged.
To remedy. this I reverse the position of the nipping rollers and so arrange them
that the fabric will pull against the nipping roller running in the stationary
bearings, by which means the tightly drawn fabric cannot separate the said rollers
as is now the case, and the nip on the cloth will be always the same..
This part of my invention is shewn in Fig. 1, where A and B are the nipping
rollers, the former of which I now arrange to be the yielding roller, and this takes
place in consequence of the bearing which carries the axle of the roller 'A being in
contact with a strong spiral spring I, see Fig. 2. According to prévious arrange-
ments as shewn in Fig. 2, the nipping roller B was the yielding roller, and as the
fabric to be nipped passed over the roller B as shewn at f, in dotted line, it follows
that if the fabric got fast or drawn tight, that the roller would yield and leave the
roller A in such manner that the contact was broken, consequently the roller A
which was positively driven would continue to revolve and would damage the piece
which was not moving for the time being, but according to present arrangement
as shewn in Fig. 1, the roller B is placed in stationary bearings, so that if the piece
gets fast or drawn tight it cannot draw the roller Baway from the nipping roller A,
consequently the nip of the cloth is never destroyed, but always remains the same,
by this means a broken nip cannot now take place.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
Firstly: The employment of scrapers C and D, where the point of contact with
the nipping rollers is above the centre and not below as at present.
Secondly:-The employment of nipping roller B, arranged in stationary bearings
as set forth, by which means the pull of the fabric cannot draw it away from the
roller A.
D
19
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1000