Improvements in Loom Let-off Mechanisms.
Year: 1893

page_text: Date of Application, 15th Nov., 1893
Complete Specification Left, 14th Sept., 1894-Accepted, 20th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in Loom Let-off Mechanisms.
We, W. HAGGAS SONS AND COMPANY LIMITED of Oakworth near Keighley
in the County of York, Manufacturers, and JOSEPH MOORE of the same place,
Overlooker, do hereby declare the nature of this invention to be as follows, that is
to say:
It relates to that class of loom let-off mechanisms wherein the unwinding
of the warp from the warp beam is performed under or against the retarding
action of friction ropes encircling the hoops or ruffles on the ends of said
beam and this invention consists of arranging said ropes in combination with
suitable lever and other mechanism so that an even drag upon, or tension of, the
warp will be automatically maintained from the commencement of the warp to
its finish.
In accordance with this invention the usual kind of friction rope is employed,
the same being wound around the warp beam in the well known manner with the
exception that one end of each rope is attached to the framework while the other
end is fixed or attached to the moveable parts upon which the back rail or bearer,
over which the warp presses, is mounted.
This moveable back bearer or rail is operated, by suitable intervening levers,
connecting rods, weights and other parts which cause it to move in the opposite
direction to or against the drag or pull of the warp which passes over it, so that
when the drag of said warp is less than the force exerted by the weights referred
to then the back-rail is moved in one direction while when the pull on the back
rail by the warp exceeds that by the weights then the said back rail moves in
the other direction.
As the manner in which the friction ropes are coupled or attached to the back-
rail or to the parts operating same is such that when said back rail is moved by
the warp, said ropes are caused to release their hold of the beam which will then
more freely rotate, while when said rail is moved by the weights then the ropes
are made to tighten their grip on said beam; it will be seen that irrespective of
the varying diameter of the warp beam by the unwinding of the warp therefrom,
there is only the regular or constant force of the weights to overcome during or
throughout the whole of said unwinding operation.
By this employment of the well known kind of friction rope that most desirable
and natural yield at each beat up of the weft is secured while by its arrangement
in combination with the parts above described, the usually attendant disadvantages
of its unvarying grip on the warp beam throughout its entire motions notwith-
standing the ever varying conditions of this latter are entirely avoided, so that at
the commencement of the weaving of a warp if the necessary weight to be placed
on the levers for operating the back rail has been determined no further adjust-
ment of such weight is necessary, and to facilitate such adjustment the lever on
which the weight or weights is or are mounted, is graduated and marked with
certain figures or letters so that reference thereto may be made and a perfect
record kept of the exact positions that a given weight must maintain as being
necessary for the weaving of a given quality, inake or strength of piece or fabric.
Dated this 14th day of November 1893.

page_text: We, W. HAGGAS SONS AND COMPANY LIMITED of Oakworth near Keighley
in the County of York, Manufacturers, and JOSEPH MOORE of the same place,
Overlooker, 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 :-
It relates to that class of loom let-off mechanisms wherein the unwinding
of the warp from the warp beam is performed under or against the retarding
action of friction ropes encircling the hoops or ruffles on the ends of said
beam, and this invention consists of arranging said ropes in combination with
suitable lever and other mechanism so that an even drag upon, or tension of the
warp will be automatically maintained from the commencement of the warp to
its finish.
In the accompanying sheets of drawings illustrative of our invention;—
Fig. 1 is sectional end view of the back portion of a loom showing the warp
beam and our improved mechanism applied thereto.
Fig. 2 is sectional front elevation of a loom and shows the arrangement of our
several improved parts within same.
Figs. 3 and 4 are drawings in detail hereinafter referred to.
Figs. 5 and 6 are similar views to Figs. 1 and 2 but are illustrative of a modifica-
tion hereinafter explained.
A indicates the end frame of the loom.
In accordance with this invention the usual kind of friction rope a a¹ is employed,
the same being wound around the warp beam in the well known manner with the
exception that this winding is in the opposite direction to that heretofore followed,
and one end a² of each rope a and a is attached to the framework c while the
other end a is fixed or attached to the lever d or d' upon which levers the
back rail e, over which the warp f passes is mounted.
This moveable back-rail e is acted upon by the weight g through the lever h,
rod k, connecting bar m rods nn' springs o o' (which slightly yield on the beat up
of the weft and so more nearly meet the natural requirements of the warp at such
time) and levers dd' so as to be moved by them in the opposite direction to or
against the drag or pull of the warpf which passes over said rail e consequently
when the drag of said warpf is less than the force exerted by he weight g then
the back-rail e is moved in the direction indicated by the arrow p while when the
pull on the said back-rail e by the warp exceeds the force of the weight g then
the raile is moved in the opposite direction to that indicated by the said
arrow P.
As the manner in which the ropes a a¹ are coupled or attached to the back rail e
or the levers d d' which carry this rail, is such that when said back rail is moved
by the warp said ropes a a' are caused to release their hold of the beam b which
will then more freely rotate, while when said rail e is moved by the weight g they
(said ropes a a) are made to tighten their grip on said beam b; it will be seen that
irrespective of the varying diameter of the warp-beam 6 by the unwinding there-
from of the warpf, there is only the regular or constant force of the weight g to
overcome during or throughout the whole of said unwinding operation.
Instead of the lever h being arranged as shown by Figs. 1 and 2, by which
arrangement it is made to extend beyond the beam b, the shaft r mounted to
oscillate in the bearings ss, and the levert might be employed as intervening
parts between said lever h and the rod k, by which means the weight g is brought
well under and within the space covered by the beam b.

page_text: Again when this improved mechanism has to be applied to very broad or wide
looms, instead of the connecting bar m, rod k and levert being employed, the
rods nn' are lengthened to be coupled to the levers uu¹ which are connected
together by the rod extending lengthwise the loom, so that by the shaft w and
the usual lever hand weight g the force of this latter may be made to act upon the
back rail e as desired.
By the employment of these well known kind of friction ropes a a' that most
desirable and natural yield at each beat up of the weft is secured, while by these
ropes a a¹ being arranged in combination with the parts above described the usually
attendant disadvantages incident to the employment of the usual arrangement of
weighting bars by the unvarying grip of the ropes on the warp beam throughout
its entire motions notwithstanding the ever varying conditions of this latter, are
entirely avoided so that at the commencement of the weaving of a warp if the
necessary weight or proper position of same to be placed on the lever h has been
determined no further adjustment of such weight necessary, and to facilitate
such adjustment the lever h is graduated and marked with figures or letters or both
BO that reference thereto may be made and a perfect record kept of the exact
position necessary for the weaving of a given quality, make or strength of piece
or fabric.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we would have it
understood that we are perfectly aware that the moveable back rail of a loom has
often been used as a medium through which the tension on the warp in such loom
has been regulated hence we do not broadly lay claim to its use but what we
consider as new and of our invention and therefore claim is ;-
1. The arrangement and combination of means whereby the two ropes for
applying friction to the warp-beam of a loom by the actions of one weight lever
are brought directly under the control of, so as to be automatically regulated by
the tension of the warp as it is being unwound therefrom substantially as herein
specified.
2. The combination of a back-rail, pivoted levers for carrying said back-rail,
a warp beam, friction ropes at each end of said warp beam arranged to have one
of each of their ends attached to the framework of a loom, while the other of said
ends are attached to the levers carrying the back-rail, or to said back-rail, and
means for operating said levers substantially as specified.
Dated this 13th day of September 1894.
WM. HAGGAS, SONS & CO., LTD.,
JOSEPH MOORE,
Per Samuel Hey,
Agent.