IMPROVEMENTS IN LOOMS FOR WEAVING
Year: 1877

page_text: LETTERS PATENT to John Hall, of Preston, in the County of Lancaster, Cotton
Manufacturer, for the Invention of "IMPROVEMENTS IN LOOMS FOR WEAVING."
PROVISIONAL SPECIFICATION left by the said John Hall at the Office of
the Commissioners of Patents on the 14th May 1877.
JOHN HALL, of Preston, in the County of Lancaster, Cotton Manufacturer.
PROVEMENTS IN LOOMS FOR WEAVING."
"IM-
This Invention has reference to that class of "letting-off" motion in looms for
weaving in which the yarn beam is provided with notched wheels, acted upon by
levers having their fulcra in the frame of the loom, such levers being by suitable
attachments caused to press upon the teeth of the notched wheels, which are so
arranged alternately with regard to each other at each end of the beam that by the
time one lever is raised to its highest point the other lever is only raised half way.
According to my Invention I make the notched wheels of considerable width and
the same diameter as the wooden barrel of the beam, thus the beam flanges can be
removed from the beam without necessitating the removal of the notched wheels.
The latter do not require to be taken off during the process of dressing the yarn,
and the risk of breakage of the notched wheels is very materially reduced. At each
side of the loom, and at right angles to the beam, I arrange two levers, provided on
their lower sides with studs or projections which press upon the teeth of the notched
wheels. These levers at the ends furthest from the beam are pivoted on a stud,
but are slotted so as to be capable of a to-and-fro motion lengthwise, to accom-
modate themselves to the oscillation of the beam during weaving. The four levers
(two above each notched wheel at each end of the beam) are so arranged relatively
to each other as that the teeth on the notched wheels will pass under the studs or
projections on the under sides of the levers alternately or in rotation. The outer
ends of the levers which press upon the notched wheels project somewhat over the
notched wheels, and are connected by cords or wires passing over pulleys, or
attached to the extremities of bell-crank levers to spiral springs attached to the
slay sword, one on each side.
By this arrangement the yarn will be tightest when the slay or reed strikes the

page_text: cloth, and slackest when the shed is open, by reason of the to-and-fro motion of the
slay, thus reducing the pressure on the healds, and to a considerable extent relieving
the tension on the yarn when such tension is least required; and the amount of
pressure to be exerted on the beam can readily be regulated, at the front of the
loom, a screw and wing nut being arranged at the front of the slay for this purpose.
By my Invention also the weight of the motion is reduced to a considerable
extent as compared with others of the same class, and a steadier let-off is obtained.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Hall in the Great Seal Patent Office on the 13th November
1877.
JOHN HALL, of Preston, in the County of Lancaster, Cotton Manufacturer.
PROVEMENTS IN LOOMS FOR WEAVING."
"
"IM-
This Invention has reference to that class of "letting-off" motion in looms for
weaving in which the yarn beam is provided with notched wheels, acted upon by
levers having their fulcra in the frame of the loom, such levers being by suitable
attachments caused to press upon the teeth of the notched wheels, which are so
arranged alternately with regard to each other at each end of the beam that by the
time one lever is raised to its highest point the other lever is only raised half way.
This class of letting-off motion is already well known, and I lay no claim to it.
apart from my improvements, as herein-after described and shewn in the accom-
panying Sheet of Drawings.
According to my Invention I make the notched wheels of considerable width and
the same diameter as the wooden barrel of the beam, thus the beam flanges can be
removed from the beam without necessitating the removal of the notched wheels.
The latter do not require to be taken off during the process of dressing the yarn,
and the risk of breakage of the notched wheels is very materially reduced.
In the Drawings Fig. 1 is a sectional end view, showing so much of a loom as is
necessary to illustrate the application of my Invention; and Figs. 2 and 3 are front
and end views shewing my improved apparatus to a larger scale, omitting the con-
nection with the slay.
At each side of the loom, and at right angles to the beam, I arrange two levers
a, a¹, provided on their lower sides with studs or projections b, which press upon the
teeth of the notched wheels c. These levers at the ends furthest from the beam are
pivoted on a stud d, but are slotted so as to be capable of a to-and-fro motion
lengthwise, to accommodate themselves to the oscillation of the beam during
weaving. The slotting of the levers a, a², also permits of the "letting back" of the
yarn beam by the attendant from the front of the loom, for by releasing the gear
which rotates the cloth roller the pressure of the levers upon the peripheries of the
notched wheels will cause the beam to partially rotate in a backward direction,
thus obviating the necessity of the attendant having to go round to the back of the
loom to turn the beam back by hand, as usually practised. The four levers (two
above each notched wheel at each end of the beam), of which only one set or pair
is shewn in the Drawings, a corresponding set or pair being fitted upon the other
end of the beam, are so arranged relatively to cach other as that the teeth on the
notched wheels will pass under the studs or projections on the under sides of the
levers alternately or in rotation. Each of the notched wheels is provided with two
series of notches or teeth, which it will be observed by reference to Fig. 2 are
arranged in alternate positions relatively to each other. The outer ends of the
levers a, a, which press upon the notched wheels project somewhat over the notched
wheels, and are connected by cords or wires f, passing over pulleys or attached to
the extremities of bell-crank levers g (see Fig. 1) to spiral springs h, attached to the
slay sword i, one on each side.

page_text: By this arrangement the yarn will be tightest when the slay or reed k strikes
the cloth, and slackest when the shed is open by reason of the to-and-fro motion of
the slay, thus reducing the pressure on the healds, and to a considerable extent
relieving the tension, on the yarn when such tension is least required, and the
amount of pressure to be exerted on the beam can readily be regulated at the front
of the loom, a screw and wing nut Z being arranged at the front of the slay for this
purpose. m is an arm to prevent the levers being pushed too far back in the event
of the studs or projections b sticking in the wheel notches. This arm ensures the
passing of the studs or projections from one tooth to the next.
It will be observed that both the levers a, a, and the arms m are capable of
being turned over out of the way whilst one beam is removed and another sub-
stituted. n is a notch or key to prevent the notched wheels turning round upon
the beam end.
By my Invention, in addition to the other advantages, the weight of the motion
reduced to a considerable extent as compared with others of the same class, and
a steadier let-off is obtained.
Having now described the nature of my said Invention, and the manner of
carrying it into practical effect, I would have it understood that what I consider to
be novel and original, and therefore claim as the Invention secured to me under the
Letters Patent herein-before in part recited is, the improved letting-off motion,
constructed, arranged, and operating as herein-before described and shewn in the
accompanying Sheet of Drawings.
In witness whereof, I, the said John Hall, have hereunto set my hand and
seal, this Eighth day of November, in the year of our Lord One thousand
eight hundred and seventy-seven.
JOHN HALL. (LS.)