IMPROVEMENT IN LET OFF MECHANISM FOR LOOMS
Year: 1884

page_text: COMPLETE SPECIFICATION.
I HERBERT JOHN HADDAN, of 67 Strand, in the City of Westminster, Civil
Engineer, do hereby declare the nature of my invention for IMPROVEMENT
IN LET OFF MECHANISM FOR LOOMS, a communication to me from abroad by
Clarence Frederick Jewett, of 76 State Street, Boston, Massachusetts, United
States of America, Manufacturer, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
In the accompanying drawings: Fig 1 is an elevation partly in section and Fig 2
an end view also partly in section showing a warp bean and the improved lot off
mechanism. Fig 3 is a longitudinal section of one of the extensible bearing
rollers, upon which the warp beam is supported.
The nature of the invention is defined in the claims hereinafter presented.
In Fig 2 the "let off" mechanism is shown as adapted to a vertically movable
loom lay but it is equally applicable to a horizontally moving or vibratory lay of a
common loom, the lay shown at A, being provided with a suitable pawl a, to be
reciprocated by it, in a manner to cause such pawl to engage with the teeth of the
ratchet wheel B of the let off mechanism and intermittently revolve the said wheel
to the necessary extent. Resting on the serrated periphery of the ratchet wheel is
one or more retaining pawls b, pivoted to the standard c, extending upward from
the loom frame C.
The warp beam loaded with yarn, as shown at D, is provided at its opposite ends
with journals d, d, each of which is shown as extending between the two prongs e, e,
of one of two adjustable guide forks E, E. These guide forks rest on two slotted
brackets F, F, and are adjustable thereon nearer to or further from each other
rectilinearly in order to adapt them to warp beams of different lengths as may be
required. From each fork E a screw f extends down through the slot g, in the
bracket, such screw having a nut h screwed upon it, and against the underside of
the bracket,
The yarn load of the warp beam rests circumferentially upon two supporting
and extensible rollers G, G, arranged horizontally and parallel with each other, and
at a suitable distance apart. Each of these rollers consists of a long cylinder i, two

page_text: shorter cylinders k, k and two thimbles 1, l, arranged as shown in Figs 1 and 3,
and adapted to two shafts or spindles m, m arranged with their axes in one straight
line. The median or longest cylinder 2, has the two spindles or shafts extending
into it axially and concentrically as represented it being connected to such shafts
or spindles by a spline or feather connection, to enable each of them to slide
lengthwise in it, the said cylinder. Each of the auxiliary or lesser cylinders k, k
is applied in the same manner to one of the spindles, there being on one of the
spindles and between the median and one of the lesser cylinders, a spur gear m¹,
which is also applied to the spindle by a "feather connection."
Each thimble has a diameter equal to that of the cylinder i, and encompasses
and fits to one of the cylinders k, and consists of a tube n and a wheel or head o,
the latter being inserted in such tube at one end thereof and fastened to it. A set
screw 2, screwed through the hub of the wheel o and against the spindle serves to
confine such wheel. to the spindle. From the above it will be seen that each
thimble can be moved lengthwise upon its sustaining roller, so as to increase the
length of the roller G, as a warp beam to rest on it may require, the spindle of
the thimble being movable at the same time in the cylinder i and one of the
cylinders k.
.
The two spindles rest in bearings in two stationary standards 7, r, extending up
between the median and secondary cylinders of each roller G, whose gear m¹
engages with the terminal gear n¹ of a train n¹, o¹ and p¹, in connection with and
driven by the ratchet wheel B.
From the above it will be seen that the extensible bearing rolls G, G, will be
revolved intermittently at a uniform speed as the lay may be in movement, and
consequently as the load of the warp beam rests directly on the said two rollers,
such load will be revolved so as to cause its warp yarns to be delivered or "let off
at a uniform rate, as may be required.
"
The loom is to be supposed to be calculated for weaving cloth of any width between
certain adopted extremes, as from a yard and a half to two yards for example.
By having each roller G extensible as set forth, it can be adapted to any warp
beam that can be used in the loom, whatever may be the length of the load of
yarn of such beam,
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 :-
1. The combination of extensible rollers substantially as described, with
mechanism for intermittently revolving them as set forth, and a warp beam as
explained.
2. The combination of two guide forks E, adjustable as described, with a warp
beam and with two extensible rollers G, substantially as represented, arranged and
provided with mechanism for intermittently revolving them as and for the purpose
specified.
3. The extensible roller G, composed of the three cylinders, the two spindles
and the two thimbles, constructed arranged and adapted substantially as set forth.
" n
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