Improvements in Let-off Mechanisms for Looms.
Year: 1892

page_text: Date of Application, 4th July, 1892
..Complete Specification Left. 4th Apr., 1393-Accepted,. 13th May, 1893
PROVISIONAL SPECIFICATION.
Improvements in Let-off Mechanisms for Looms.
I, HEBDEN WRIGHT of the firm of John Wright of Ingrow near Keighley in
the County of York, Manufacturer do hereby declare the nature of this invention
to be as follows, that is to say :-
It relates to improvements in that class of mechanism which is known as
friction" let-off' mechanism; and consists of constructing and arranging the parts
forming said mechanism so that certain advantages well known as being incident
to the use of ropes and. levers are secured with the additional advantages accruing
through my said invention enabling the engagement or disengagement of the warp
beam to be readily effected for purposes well understood.
In carrying out my said invention the warp beam is mounted in its usual
supports, and over the hoops attached to each of its extremities are made to fit
friction-clamps hinged at one end to the framework of the loom while a pressure
spring is applied to the other.
Beneath the said hoops on the warp beam are other friction clamps that are
carried by the arms of levers which are arranged to be manually operated by
another lever so as to press against said hoops with sufficient force to raise the
axial pins of the warp beam, against the pressure of the spring on the superposed
clamps, clear of their supports, in this manner constituting said clamps the sole
supports for said warp beam the rotary motion of which they retard in accordance
with the pressure imparted to them by their springs, this pressure being diminished
or increased by the tightening or slacking of a screw as is found necessary.
When the hand lever is moved from being retained to hold the hoops of the
warp beam within the friction clamps as above described said warp beam is allowed
to assume its position in its ordinary supports and so may be freely moved by the
weaver, while by the replacing of the said hand lever the warp beam is placed into
proper operating condition.
On narrow looms the levers alone are long enough to reach from each side to a
central position where they are operated by the hand lever, while in broad looms
these levers are arranged to be coupled together by suitable connecting rods' so
that on both sides they are simultaneously operated by the hand-lever.
Dated this 2nd day of July 1892
HEBDEN WRIGHT,
Per Samuel Hey,
Agent.
COMPLETE SPECIFICATION.
Improvements in Let-off Mechanisms for Looms.
I, HEBDEN WRIGHT of the firm of John Wright of Ingrow near Keighley in
the County of York, Manufacturer, 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 improvements in that class of mechanisin used in connection with
looms, which is known as "friction let-off' mechanism," and consists of constructing
and arranging the parts forming said mechanism so that certain advantages well
known as being incident to the use of the old and common rope and lever devices,
which advantages may be characterised as consisting of the peculiar feature that
these means possess in being able to allow the warp beam to be slightly raised or
Prian Q11

page_text: moved bodily while at all times they grip them so that, their rotary motion is
retarded by the incessant friction of the entwining ropes, are secured with the
additional advantages accruing through my said improved means enabling the
weaver or operative to disengage or to engage the warp beam as is from time to
time found necessary for purposes well understood by those skilled in the art.
In the accompanying sheets of drawings which are illustrative of my invention.
Fig. 1 is back elevation of a portion of the framework of a loom in which is
mounted a warp beam to which my improved mechanism is shown as applied.
Fig. 2 is sectional end elevation on line A B of parts shown by Fig. 1 and as
seen in the direction of arrow .
Fig. 3 is a similar view to Fig. 1 but shows certain parts omitted and others in
section so that parts hid in Fig. 1 are now illustrated.
Fig. 4 is end elevation of parts shown by Fig. 1 and as seen on the outside of
the loom's end frame.
Fig. 5 is a similar view to Fig. 1 but shows the arrangement of the parts forming
my improved mechanism as when used in connection with a broad loom.
Fig. 6 is a similar view to Fig. 2 but is illustrative of parts shown by Fig. 5.
Fig. 7 is back elevation of one end of the warp beam and other parts applied
thereto, in their complete form, certain of such parts being omitted in Fig. 5.
Similar figures and letters of reference indicate similar parts throughout the
several views.
In carrying out my said invention I mount the warp beam & in its usual supports
as in the notches or bearing spaces c¹ of the end frames d, and over the
hoops e, e which are attached to or fixed on each of the extremities of the beam b,
I make to fit the friction-clamps the same being pivotted or hinged at their
respective ends g to the end frames d d' while at their other ends the pressure
springs are applied. The tension on these pressure springs being arranged
to be increased or diminished by the tightening or loosening of the nuts on their
respective screwed hooks which pass loosely through fixed bearings mm² as
shown.
"
Beneath the hoops e e¹ on the beam are other friction clamps (these
clamps n n' as well as the others have their inner surfaces covered with roller-
cloth, leather or other suitable frictioning material for purposes well known) that are
carried by their shanks n² n³ being hinged or otherwise mounted upon the armis o² o³
of the levers o o respectively, both of the other arms o os of these levers o o',
which are pivotted at p pl, being coupled by the link to the lever s pivotted at s
a handle being formed on the outer end of this lever s, so that by the weaver or
operative manually lifting this handle to place it over its retaining piece t (its
jointings or elasticity allowing it sufficient lateral motion so to do, while the gain in
leverage reduces the power necessary to effect such a movement to such an extent
that it may easily be accomplished even against the pressure of the springs hh',)
the clamps n n' are pressed against the hoops e el with sufficient force to raise the
axial pins of the beam & clear of the supports or bottom of the notches c, in
this manner constituting said clamps the sole supports for said beam b the
rotary motion of which they retard.
By the beam being thus entirely within the grip of its upper and lower
clamps, and un' respectively (the yielding of the springs h h which press the
former into contact with it allowing its slight vertical movement caused by the
pulling of the warp u on the beat-up of each shot of weft, while the natural
resilience of the levers o, o' and s, even when made in cast iron, causes the
clamps n n to follow said beam in its said upward movements so as to at all times
secure this grip,) the advantages desired are attained.
When the weaver or operative desires to manually rotate the beam as is
occasionally necessary, by moving the levers from its holder t and allowing it to
descend, the beam is allowed to descend until its axial pins arrive at the
bottom of the notches c c' in which position they are arrested while the clamps un
may continue to descend, thus allowing the beam to be freely rotated about its

page_text: axial pins bb, the replacing of the lever s upon the part adjusting both the warp-
beam and its frictioning devices in proper operating condition.
In carrying out the application of my invention to broad looms instead of
forming levers to reach a central part by which arrangement one hand lever may
operate both of them as is herein before described, I form the lower clamps n n¹
upon the upper ends of the levers ev which operate in connection with the
levers ww, the fulcrums of the former being the pins carried by fixed
bearings yy (the upper ends y, see Fig. 6, of these being bent to form the fulcrums.
for the upper clamps ff), each pair of these levers forming a kind of toggle joint,.
and on the lever w is fixed the operating arm we² which is moved in a vertical
direction by the handle and cam lever this lever being held in its elevated
position by the yielding spring (which is detachable from its pin to allow the
levers z, w, w w' and v v and the beam to descend for disengaging purposes as.
before described) so that by the levers being coupled together with the rod w the
necessary resilience of the levers and parts supporting the beam & is secured.
÷
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is.-
-
1. In loom let-off mechanism the combination with a warp beam of superposed
friction clamps arranged to be forced into contact therewith by springs, supporting
clamps mounted on levers so that they may be moved to raise said warp beam from
resting upon its bearings in the loom's framework, and means for supporting said
levers when moved thus to retain said warp beam substantially as and for the
purposes specified.
2. In loom let-off mechanism the combination of a warp beam and its resiliently
superposed and supporting friction-clamps the latter being arranged to carry same
as well as to retard its rotary motion substantially as set forth.
3. In loom let-off mechanism the combination with a warp beam and its super-
posed resilient and supporting clamps of levers arranged in connection with said
supporting clamps in such a manner as to enable their ready displacement substan-
tially as and for the purposes specified.
4. In loom let-off mechanism the combination of toggle-levers and means for
coupling same together, with friction-clamps arranged and formed to operate in
connection therewith substantially as set forth.
Dated this 2nd dove of A il 1202
HEBDEN WRIGHT,
Per Samuel Hey,
Agent.