IMPROVEMENTS IN LOOMS FOR WEAVING
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Alexander Dick Stewart at the Office
of the Commissioners of Patents on the 4th October 1878.
ALEXANDER DICK STEWART, of Hamilton, in the County of Lanark, North
Britain. "IMPROVEMENTS IN LOOMS FOR WEAVING."
This Invention relates to the improvement of the "pacing" of power loom work,
and to the machinery by which the improved "pacing" is effected, so as to convert
it from a discontinuous, disconnected, indefinite, and unreliable drag into a con-
tinuous, connected, positive, and reliable portion of the direct-acting machinery of
the loom, being in gear with and under direct control of the uptaking motion of the
loom, and having direct power over the warp in the loom, either to retard or acce-
lerate its progressive motion according to the will of the operator, thus insuring the
evenness of the wefting throughout. It also by the reciprocal motion communicated
to the rollers herein-after described cases the warp, yarn, heddles or healds, shedding
machinery, or engines, and generally makes a better working web, besides giving
at the proper moment the requisite power of " pacing."
The Invention consists as follows:-Any number of cylindrical rollers of an
uniform length of any suitable substance, and of the same or different sizes, having
gudgeons projecting from their ends and having their surfaces covered or coated
with flannel, cloth, india-rubber, or any other suitable material or compound, and
having pinions fixed on one or both ends, are geared into each other in such a way
and in proper proportion of teeth that when one of the rollers is turned or driven
the whole of the circumferential surfaces of the other rollers will travel at exactly the
same rate of speed. Under, over, between, and partially round these rollers the
warp yarn is conducted, and the rollers are pressed together by a screw or its
equivalent sufficiently to prevent by the friction and pressure the slipping of the
warp as a whole or any considerable portion of it in the process of weaving, thus
rendering the warp's motion completely subservient to any forward, backward, or
stationary force that may be applied to one of the rollers. These rollers are fixed
and kept in position by brackets supported by frames which are bolted to the low
back bar of the loom by studs, paps, and brackets in such a way as to allow of the
whole apparatus (that is, the frames, rollers, and the warp yarn fixed by the rollers)

page_text: being moved backward and forwards to any desired extent. To the centre of the
breadth of these frames and on a level with the crank on top shaft of the loom paps
are cast, and to these paps by means of studs connecting rods having jaws which
pass round each side of the paps, are connected in such a way as to leave them at
freedom to move up and down. The opposite ends of these connecting rods are
made by means of movable covers to encircle two eccentrics bolted to the top shaft
of the loom, and which every time the loom makes one revolution give a backward
and forward motion to the connecting rods, frames, rollers, and the warp yarn fixed
between the rollers, which backward and forward motion is so timed by the
arrangement of the eccentrics on the crank shaft as to tighten the warp full back
when the lay is driving up the shot of weft into the fell of the cloth, and to slack
the warp out towards the heddles in front of the loom when the wypers on the low
shaft are shedding the web, thus alternately tightening and slackening the warp
yarn at the proper moments to effect great power of "pacing" and great ease in
shedding. The eccentrics are each preferably formed in two halves and fixed firmly
to the top shaft by set screws or their equivalent. On the end of one of the rollers
which hold the yarn a pinion is placed and arranged on the gudgeon in such a way
that the pinion can easily be moved backwards and forwards upon the gudgeon,
but cannot be turned round without turning the roller; this is effected by putting
a feather key on the shaft, and key seating the pinion to suit the feather. This
last-named pinion is that which regulates the speed of all the rollers and can be
changed to suit any speed. The pinion is geared into an intermediate pinion fixed
below it, and in the same line of centres by a stud fixed in a slot in a projection of
the frame, and this intermediate pinion is in turn geared into another pinion fixed
in a small shaft, one end of which passes through a bracket on the back of the
frame, and the other end put into a socket in a bracket bolted to the side framing
of the loom near the middle and back thereof. The end of another shaft which
runs from another socket in the same bracket, but at right angles to a small shaft,
is connected with the above-named small shaft by a mitre wheel which gears into
a mitre bevel wheel on the small shaft, and this second shaft extends to the front
of the loom close to and on a level with the gudgeon of the uptaking card beam on
the end of the beam next the uptaking motion, in which position it is held by a
bracket bolted to the side of the loom. The front end of this shaft and the gudgeon
of the emery beam are geared and connected by mitre or bevel pinions fixed on
both.
The
The way in which the mechanism herein-before described acts is as follows :-
The web is put into the loom in the usual manner and knotted up. The rollers
which allow the warp to be passed below, above, between, and partially round them
are for this purposo removed, this being easily and expeditiously effected from the
manner in which the machinery is constructed, and after being properly adjusted
the rollers are pressed together sufficiently to hold the yarn from slipping. The
warp having been drawn tight by pulling over the up-taking motion the change
pinion on the end of the driving roller is put in gear and the loom put on.
mitro on the gudgeon of the uptaking card beam drives tho first shaft, and this first
sbaft in turn drives the small shaft, which again puts in motion the intermediate
pinion, and this propels the change pinion on the end of the driving roller, which
roller being geared into the other rollers, as herein-before described, drives tho
whole, and these rollers propel or check the warp according as they are propelled or
checked by the up-taking beam. The whole motion is actuated backwards and
forwards by the eccentrics so as to allow the web to shed freely, and to apply the
proper amount of " pace."