Improvements in Let-off Mechanism for Looms.
Year: 1899

page_text: Date of Application, 28th Apr., 1899
Complete Specification Left. 22nd Aug. 1899-Accepted. 14th Oct: 1899
Improvements in Let-off Mechanism for Looms.
I, OTTO WALTER SCHAUM, of Corner Glenwood Avenue, and Second Street, in
the City of Philadelphia, County of Philadelphia, and State of Pennsylvania,
U.S.A., Textile Machinery Manufacturer, do hereby declare the nature of this
invention to be as follows:-
-
My invention relates to let-off mechanisms for looms and especially for narrow-
ware looms.
Heretofore weighted levers have been employed as means for controlling the
tension upon the warp. The principal object of my invention is, therefore, to
so construct and relatively arrange these levers as to not only render them sus-
ceptible of greater relative movement but also, by virtue of their peculiar arrange-
ment, to materially improve upon the analogous devices in so far as the desired
uniform strain upon the warp is concerned.
It was practically impossible heretofore to secure at all times a uniform tension
upon the warp, for, although this might be accomplished while the loom was
being operated under normal circumstances (that is to say, in a forward direction)
when the machine was reversed or the warp let back in order to pick out the web,
the weight of practically but one set of levers instead of both sets-as under said
normal or forward operation-would be acting upon said warp. Furthermore,
the arrangement of the levers was such that whenever the levers were separated
or "opened," the separating or opening action was dependent entirely upon one,
and not both, of said levers. As a result, the action upon the warp was different
when the machine was operating forwardly from what it was when it was operat-
ing backwards, and the web consequently varied in width.
In view of the foregoing considerations, therefore, the invention hereinafter
particularly described consists in the improved let-off mechanism and in the
combination and arrangement of its parts, substantially as will be hereinafter
described.
In the single figure of the accompanying drawing my improved let-off mechan-
ism is shown in side elevation, being mounted as usual at the rear of the loom,
a portion of whose framework is shown partially in section and partially in
dotted lines.
In said drawing, a indicates the rear portion of the framework of the loom,
and a', a² and a³ designate three of the cross-beams or rails which form a part of
the frame and which support my improved let-off mechanism.
a represents one of a pair of side-frames or supports having several arms
whereby it is secured to the various cross-beams or rails above-mentioned.
In bearings or recesses b formed at suitable intervals in said side-frames are
journalled the ends of the various beam-shafts; the shafts for the ground-warn
beams c and c are designated by the letters d and d', respectively, and the shafts
for the edge- and binder-warp beams e and e-the latter of which beams is
situated above the former-are designated by the reference letters f and f¹,
respectively.

page_text: g designates levers-each of which constitutes one of a pair-that are ful
crumed in the side frame a at points g' below the bearings 6 of each ground
warp beam and g² and g³ each designate one of a pair of similarly fulcrumed
levers, the former being for the edge-warp, and substantially like the levers
in shape, and the latter being for the binder-warp and differing slightly in
form from said lever g.
The various pairs of levers are connected by one or more rods h which serve
as racks for weights h¹.
h² indicates levers which are fulcrumed upon, and are preferably shorter than
the various levers already described, and each of which is provided upon its
under side with a heel or lug h³ with which the longer levers are adapted to con-
tact when raised. Each of the warp-beams is provided at its ends with a peri-
pherally grooved disk h in which fit flexible friction devices, each consisting
of a band h³ provided at one end with a threaded pin ho having an adjusting
nuth and extending in the case of the two lower or ground-warp beams, through
enlargements 8 on the end of projections h" formed upon the side-frames a* and,
in the case of the upper or binder and edge-warps, through projections
formed on said side-frames. The forward end of each band is provided with
a hook h engaging a bent pin 2 formed upon each lever h².
It should be remarked that the levers h2 should be so fulcrumed in the longer
levers that their fulcruming points will be somewhat contiguous to the points
of securing the bands to said levers, so that when their rear ends are actuated
their forward ends will have appreciable movement; it should also be remarked
that the shorter levers h² are angular in shape, their free ends being held by the
bands considerably above their fulcrumed ends.
At the ends of the shorter levers and upon rods i contacting them and in
vertical brackets integrally formed with each longer lever and upon rods
connecting corresponding brackets, are journalled rollers for the warp. Said
warp extends from each beam to and over the rollers carried by the levers, and
then over other rollers suitably journalled in a pair of arms 2 mounted on the
beam a¹.
With regard to the construction of the longer levers, it should be stated that
each of the lower three of said levers may be adjustably fulcrumed upon the side-
frames a by virtue of the provision of a series of fulcruming apertures ; and
that the uppermost pair of levers g³ is provided at the rear end with a connect-
ing-bar serving as a rack for the counterbalance-weights kl.
In view of the foregoing, it will be seen that the motion of the shed in open-
ing will act to raise the longer levers into contact with the heels or lugs h³ of
the shorter levers, thereby raising the latter and tending to throw out of opera-
tion the braking device for the beams which each disk and band therefor con-
stitutes. This tendency to throw out of operation the braking device is
immediately counterbalanced by the consequent tendency of the longer levers
to fall. Thus the tension is preserved constantly uniform.
Moreover, the peculiar arrangement of the levers which I have herein before
described permits a comparatively great movement of the longer levers and an
increasing of the distance between them and the shorter levers, leaving to the
shorter levers for the most part the function of directly effecting the operation of
the braking device. Furthermore, when each longer lever drops it will be seen
that the fulcrumed end of the shorter lever will also drop, said shorter lever
moving about its pin 12 as a fulcruming point when said lever is moved down-
wardly as far as the band h³ will permit; the effect of the dropping of the rear
or fulcrumed end of this longer lever is to augment the increasing of the distance
between the levers which would otherwise be the function of the longer lever
alone.
Furthermore, it should be remarked that whether the loom is in normal or
active operation or not (as, for instance, when it is necessary, on account of an
error or mis-pick, to pick out the web and let the warp back), the tension is

page_text: constantly uniform, for, though the lower or longer lever may drop consider-
ably, its weight is always more or less acting on the warp in conjunction with
that of the shorter lever.
DOL
1 1000
J. P. BAYLY,
18, Fulham Place, Paddington, London, W.,
Agent for the Applicant.
Improve In DOOME
I, OPTO WALTER SCHAUM, of Corner Glenwood Avenue, and Second Street, in
the City of Philadelphia, County of Philadelphia, and State of Pennsylvania,
U.S.A., Textile Machinery 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: -
My invention relates to let-off mechanisms for looms and especially for narrow-
ware looms.
Heretofore weighted levers have been employed as means for controlling the
tension upon the warp. The principal object of my invention is, therefore, to
so construct and relatively arrange these levers as to not only render them sus-
ceptible of greater relative movement but also, by virtue of their peculiar arrange-
ment, to materially improve upon the analogous devices in so far as the desired
uniform strain upon the warp is concerned.
It was practically impossible heretofore to secure at all times a uniform tension
upon the warp, for, although this might be accomplished while the loom was
being operated under normal circumstances (that is to say, in a forward direction)
when the machine was reversed or the warp let back in order to pick out the weft,
the weight of practically but one set of levers instead of both sets-as under said
normal or forward operation-would be acting upon said warp. Furthermore,
the arrangement of the levers was such that whenever the levers were separated
or opened," the separating or opening action was dependent entirely upon one,
and not both, of said levers. As a result, the action upon the warp was different
when the machine was operating forwardly from what it was when it was operat-
ing backwards, and the web consequently varied in width.
In view of the foregoing considerations, therefore, the invention hereinafter
particularly described consists in the improved let-off mechanism and in the
combination and arrangement of its parts, substantially as will be hereinafter
described and finally embodied in the clauses of the claim.
In the single figure of the drawing filed with the Provisional Specification my
improved let-off mechanism is shown in side elevation, being mounted as usual
at the rear of the loom, a portion of whose framework is shown partially in
section and partially in dotted lines.
In said drawings, a indicates the rear portion of the framework of the loom,
and a, a² and a designate three of the cross-beams or rails which form a part of
the frame and which support my improved let-off mechanism.
a represents one of a pair of side-frames or supports having several arms
whereby it is secured to the various cross-beams or rails above-mentioned.
In bearings or recesses b formed at suitable intervals in said side-frames are
journalled the ends of the various beam-shafts; the shafts for the ground warp
beams and c¹ are designated by the letters d and d¹ respectively and the shafts
for the edge- and binder-warp beams e and e-the latter of which beams is

page_text: situated above the former-are designated by the reference letters f and f',
respectively.
g designates levers-each of which constitutes one of a pair-that are ful-
crumed in the side frame at at points g¹ below the bearings 6 of each ground-
warp beam and 92 and g³ each designate one of a pair of similarly fulcrumed
levers, the former being for the edge-warp, and substantially like the levers g
in shape, and the latter being for the binder-warp and differing slightly in
form from said lever g.
The various pairs of levers are connected by one or more rods h which serve
as racks for weights h¹.
h indicates levers which are fulcrumed upon, and are preferably shorter than,
the various levers already described, and each of which is provided upon its
under side with a heel or lug h³ with which the longer levers are adapted to con-
tact when raised. Each of the warp-beams is provided at its ends with a peri-
pherally grooved disk h in which fit flexible friction devices, each consisting
of a band h provided at one end with a threaded pin h having an adjusting-
nut and extending in the case of the two lower or ground-warp beams, through
enlargements 8 on the end of projections ho formed upon the side-frames a* and,
in the case of the upper or binder and edge-warps, through projections ho
formed on said side-frames. The forward end of each band is provided with
a hook engaging a bent pin 12 formed upon each lever h².
It should be remarked that the levers h2 should be so fulcrumed in the longer
levers that their fulcruming points will be somewhat contiguous to the points
of securing the bands to said levers, so that when their rear ends are actuated
their forward ends will have appreciable movement; it should also be remarked
that the shorter levers h² are angular in shape, their free ends being held by the
bands considerably above their fulcrumed ends.
At the ends of the shorter levers and upon rods i connecting them and in
vertical brackets integrally formed with each longer lever and upon rods
connecting corresponding brackets, are journalled rollers 3 for the warp. Said
warp extends from each beam to and over the rollers carried by the levers, and
then over other rollers suitably journalled in a pair of arms mounted on the
beam a¹.
With regard to the construction of the longer levers, it should be stated that
each of the lower three of said levers may be adjustably fulcrumed upon the side-
frames a by virtue of the provision of a series of fulcruming apertures ; and
that the uppermost pair of levers g³ is provided at the rear end with a connect-
ing-bar serving as a rack for the counterbalance-weights kl.
In view of the foregoing, it will be seen that the motion of the shed in open-
ing will act to raise the fonger levers into contact with the heels or lugs h³ of 4
the shorter levers, thereby raising the latter and tending to throw out of opera-
tion the braking device for the beams which each disk and band therefor con-
stitutes. This tendency to throw out of operation the braking device is
immediately counterbalanced by the consequent tendency of the longer levers
to fall. Thus the tension is preserved constantly uniform.
Moreover, the peculiar arrangement of the levers which I have herein before
described permits a comparatively great movement of the longer levers and an
increasing of the distance between them and the shorter levers, leaving to the
shorter levers for the most part the function of directly effecting the operation of
the braking device. Furthermore, when each longer lever drops it will be seen 5
that the fulcrumed end of the shorter lever will also drop, said shorter lever
moving about its pin 12 as a fulcruming point when said lever is moved down-
wardly as far as the band h5 will permit; the effect of the dropping of the rear
or fulcrumed end of this longer lever is to augment the increasing of the distance
between the levers which would otherwise be the function of the longer lever 5
alone.
Furthermore, it should be remarked that whether the loom is in normal or

page_text: active operation or not (as, for instance, when it is necessary, on account of an
error or mis-pick, to pick out the weft and let the warp back), the tension is
constantly uniform, for, though the lower or longer lever may drop consider-
ably, its weight is always more or less acting on the warp in conjunction with
that of the shorter lever.
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: In a let-off mechanism for looms, the combination, with a frame and with
a warp-beam journalled therein, of a pair of levers fulcrumed in said frame,
another pair of levers fulcrumed in said first-named levers and extending over
the same, and bands having frictional contact with and surrounding a portion
of said beam, said bands being connected to the frame at one of their ends and
to the last-named pair of levers at the other of their ends, the warp having a sub-
stantially over and under engagement with the free ends of the shorter and longer
levers respectively, substantially as described.
2: In a let-off mechanism for looms, the combination, with a frame and with
a warp-beam, of a pair of levers fulcrumed therein at or near one of their ends,
another pair of levers fulcrumed in said first-named levers and extending over
the same, and bands having frictional contact with and surrounding a portion of
said beam. said bands being connected to the frame at one of their ends and to the
last-named pair of levers at the other of their ends and between the fulcruming
point and the free end of said pair of levers, the warp having a substantially
over and under engagement with the free ends of the shorter and longer levers
respectively, substantially as described.
3: In a let-off mechanism for looms, the combination, with a frame and with
a warp-beam, of a pair of levers fulcrumed between their ends in said frame,
counterbalance weights suspended from one of their ends, another pair of levers
fulcrumed in said first-named levers between the other ends thereof and their
fulcruming points and extending over the same, and bands having frictional
contact with and surrounding a portion of said beam. said bands being connected
to the frame at one of their ends and to the last-named pair of levers at the other
of their ends and between the fulcruming point of said pair of levers, the warp
having a substantially over and under engagement with the free ends of the
shorter and longer levers, respectively, substantially as described.
Dated this 22nd dow of Amanat 1900
J. P. BAYLY,
18, Fulham Place, London, W. Agent for the Applicant.