Improvements relating to Let-off and Warp Tension Regulating Mechanism for Looms.
Year: 1893

page_text: Date of Application, 24th Mar., 1893
Complete Specification Left, 18th Dec., 1893-Accepted, 20th Jan., 1894
PROVISIONAL SPECIFICATION..
Improvements relating to Let-off and Warp Tension Regulating
Mechanism for Looms.
RICHARD WILBY, Mill Manager, Exchange Buildings, Marsh, Huddersfield,
do hereby declare the nature of this invention to be as follows:-
These improvements relate to a new form of let-off motion for looms, for the
which a Patent has been granted to me bearing the date of June 17th 1892, and
numbered 11367.
The figures hereinafter mentioned refer to the drawings in the above Patent
Specification.
The first of these improvements is a new method of coupling the vibrating back
bearer of the loom, to the let-off mechanism, which improvement permits of the said
mechanism being placed at any convenient position on the worm shaft, even as far
to the front of the loom as to be underneath the cloth beam.
This improvement consists of a rod reaching from the back bearer, to the ratchet
mechanism, in as straight a line as possible, the lower end of which rod works in a
step bearing bored at the proper angle in the double bearing bracket 12 Fig. 2.
A short distance from its lower end, this rod has a branch, or fork, which is
connected by set screw, or pin, to an upright cast on one of the lugs 21ª of the three
armed lever 20 Fig. 3.
The upper end of the rod is put into communication with the back bearer, by a
short arm fixed on the rod by set screw, this arm occupies a position between a
pair of jaws, which are fixed or cast on the back bearer 33 Fig. 1, the practical
working distance between the jaws being regulated by set screw, and lock nut,
which allows of the mechanism being regulated as to sensitiveness.
The whole arrangement as just described serves the same purpose as the arm 28,
rod 29, and nuts 30, 30, described in the Specification, and shewn in Fig. 1.
The second improvement is an arrangement by which the force which gives
tension to the warp, is imparted to the back-bearer in a direction opposite, or as
nearly opposite as possible, to the resultant force which the total forces of the warp
threads exert on said back bearer. This is accomplished by having the tightening
end of the springs fixed just over the back bearer, the springs lying in a line
downwards, and forwards, towards the front of the loom at an angle from the
horizontal of about 45 degrees of arc. Each spring lies between two rods, which
rods are joined together at the lower ends by a cross piece having a hole, into which
hole the spring is hooked, and below this hole is a short projection which slides
through a hole contained in a bracket which is bolted to the loom frame, the
projection having a nut on the other side of the bracket, which nut comes against
the bracket and takes the force of the springs when the warp is let slack, or when
the backbearer is taken out. The upper ends of the two rods converge together
and end in a coned point, which point enters a countersunk recess in the back
bearer.
The force of the springs is thus imparted to the back bearer through the double
rods, or grids, and in a direction which is opposite to the total resultant of the forces
of the warp threads on the back bearer. In case the back bearer has to be weighted
by weights and levers, I use levers of the first order set in the direction of the
length of the loom, the weighted ends of the levers being behind, and below the
back bearer, the short arms of the levers instead of being in a line with the long
arms, are inclined upwards from the axis at an angle of about 45 degrees. To this

page_text: short arm is connected by knuckle, or other joint, a connecting rod which ends in a
coned point, the point entering a cone shaped recess in the back bearer.
This arrangement causes the force of the weighted lever to be communicated to
the back bearer in a direction opposite to the total resultant of the forces which the
warp threads exert on the back bearer, with the result that these forces greatly
neutralize each other, and thus cause the back bearer to work with very little
friction.
Another improvement on looms which have springs to the back-bearer for the
purpose of allowing the back bearer to vibrate to the shedding, and on which looms
the beat up of the weft is too strong for the back bearer springs to resist, is the
employment of supplementary, or beat up springs, coupled, or connected between
the slay sword, and the back bearer in such a manner, that the springs are stretched
a fraction of an inch at each beat up of the weft, thus giving additional spring
force to the back bearer at the instant of each blow of the reed. The new feature
in these supplementary springs is that when not being acted upon by the slay
sword, they are still extended about three fourths of their stretching power, which
condition causes their full force to come upon the back bearer at once, and also
causes the springs to give practically the same tensional force when stretched an
eighth of an inch as when stretched one half an inch. I cause these beat up springs
to be permanently extended, by placing a rod of the proper length inside the
spring, the upper end of the rod being made smaller, and having a shoulder.
A disc of metal with a hole in the centre is partly passed between the two top coils
of the spring. The spring is stretched till the disc can be pushed over the rod, and
then the small end of the rod is passed through the hole in the disc and is riveted.
The rod in this way keeps the spring extended a predetermined amount.
Another improvement which is for the purpose of securing a longer stroke of the
ratchet mechanism, is a modification of the parts 7b, Fig. 4, and also of the
parts 10, Fig. 5. The improved parts are made on the bevil wheel principle,
the said improved parts being sectors of true bevil wheels.
A further improvement to the let-off mechanism when it has to be applied to
looms weaving very fine goods such as silk, and muslin, is a contrivance which will
lift the pawls out of gear from the ratchet wheel at intervals of one, two, or more
picks, by other means than by the vibrator of the loom, thus ensuring absolutely
the same degree of tension on the warp at each beat up of the weft. The lifting of
the pawls out of gear 1 accomplish by having a number of triangular bits cast on the
inside of the rim of the ratchet wheel 6 Fig. 1. A cranked lever is connected to
the three armed lever 20 20 Fig. 3.which rests when the pawls are in gear, on the
surface of the inside rim of the ratchet wheel, but is lifted as each triangular
protuberance passes under it, causing the three armed lever to be lifted, and the
pawls to be thrown out of gear at longer, or shorter intervals, according to the
number of such protuberances.
Dated this 24th dovr of March 1902
RICHARD WILBY.
COMPLETE SPECIFICATION.
Improvements relating to Let-off and Warp Tension Regulating
Mechanism for Looms.
I, RICHARD WILBY, Exchange Buildings, Marsh, Huddersfield in the County
of York, Mill Manager 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 :-
This invention relates to improvements in that class of let-off motion for looms
such as described in the Specification of my Patent No. 11,367 bearing date
June 17th 1892, the object of the present invention being to provide several detail

page_text: improvements the character of which will hereinafter be fully described and set
forth.
In order to assist in the complete understanding of my invention by those skilled
in the art to which it relates I have annexed hercto a sheet of explanatory drawings
in which:
Fig. 1 is a side elevation of a loom with some of my improvements applied, and
Figs. 2 to 9 views of details which will be fully described.
In referring to these I would point out that I have considered it advisable to
make use of numerals for those parts represented in the drawings which are similar
to those described in my previous Patent before referred to whilst for those parts
which generally speaking constitute the subject matter of my present invention I
have designated by letters.
The first part of my invention refers to an improved arrangement of mechanism
for connecting the vibrating back bearer 33 of the loom to the ratchet mechanism
situated on the worm shaft 4 by means of which improvements the ratchet
mechanism may be placed at any convenient position on the said worm shaft 4. In
carrying out this portion of my invention and referring more particularly to
Figs. 1, 2, 3, and 4 1 provide a rod A which extends in an inclined direction from
the vibrating back bearer 33 to the ratchet mechanism on the worm shaft 4. The
lower end a of this rod rests in a step bearing bored at the required angle in a
projection a formed on the double-bearing bracket 12 which supports the ratchet
wheel 6. Near to the lower end, the rod A. is provided with an extending arm all
as shown more clearly in Fig. 4 the object of which is to control the action of the
three armed lever 20 that puts into and takes out of gear the pawls 9 which actuate
the ratchet wheel 6. The manner of connecting the arm all to the lever 20 is
clearly shown in Fig. 4 wherein B. is a spring coiled round the stud 21 the free
ends projecting upwards one on either side of a pin " or the like carried by an
arm on the lever 20. The arm all is simply passed between the ends of the
spring band as the rod A oscillates as will be presently described the arm all
engages with one or other of the ends b b and so lifts or lowers the lever 20 to.
take out or put into gear the pawls 9 with the ratchet wheel 6. Instead of using
the means described the arm at may be passed through a slot in the arm 6
connected thereto by a link or the like but I prefer the described method as it
allows of an elastic connection. The upper end of the rod A communicates with
the back bearer 33 by means of a finger C as shown in enlarged views Figs. 2 and 3.
The free end of this finger normally occupies a position between a pair of jaws or
projections E fixed to or cast on an arm integral with the back bearer 33 so that
as the back bearer vibrates one or other of the projections E will engage with the
finger C and so oscillate the rod A and actuate the pawls 9 as previously described.
Each of the projections E may be provided with a set screw and locknut e which
can be adjusted to increase or decrease the width of the space between the jaws to
suit the different amplitudes of vibration of the back bearer. The arrangement
thus described will be seen to serve the same purpose as arm 28 rod 29 and nuts 30
described in my Patent 11367 before referred to.
or
The second part of my invention refers to an improved arrangement by which
the force that gives tension to the warp is imparted to the back bearer 33 in a
direction opposite or as nearly opposite as possible to the resultant force which the
warp threads exert on the said back bearer. For this purpose I place each of the
springs 32 behind the back bearer somewhat in the position shown and so that
the screwed bolt by which the tension of the spring is adjusted may be passed
through a bracket D fixed to the loom frame a nut or nuts being placed on the bolt
at the top side of the bracket. Each spring lies between a grid F of a shape
somewhat similar to that shown in Fig. the conical point of which engages with a
projection el formed on the arm carrying the jaws E as seen in Fig. 1 or with a
somewhat similar projection formed on the back bearer as indicated by dotted lines
in Fig. 2 whilst the lower end of the grid F passes loosely through a hole f¹
formed in a bracket F¹ attached to the loom frame. The lower end of the spring

page_text: is hooked and passed through a hole f" in the grid F. f is a nut or it may be
two nuts, one locking the other which may be adjusted on the screwed end of the
grid so as to bear against the bracket F¹ and take the full force of the spring 32
and hold it in place whenever the warp is left slack or when the back bearer is
taken out of its bearings.
A modification of the above method is to employ compression springs instead of
tension springs as shown in Fig. 6. In this method the spring is coiled round a
rod G formed at one end with a conical point whilst the other end is passed loosely
through the bracket F¹ as before and provided with a nut or nuts f for the same
purpose as those described above. The ends of the springs bear against washers
and a nut or nuts G is provided to increase or decrease the amount of
compression.
In both these methods the spring force is imparted to the back bearer by a
thrust in a direction opposite or nearly so to the resultant of the forces which the
warp threads impart to the back bearer, with the result that these opposite forces
greatly neutralise each other and cause the back bearer to vibrate with very little
friction in its bearings which is very beneficial especially when weaving goods of a
light character. In order that a uniformity of tension may be given to the warp
threads at whatever angular position the back bearer may be in the countersunk
recesses for receiving the conical ends of the grids F or screwed rods G are
made on a portion of the back bearer in the same horizontal plane or nearly so
as its axis.
The third part of my invention refers more particularly to looms weaving strong
cloth. In these looms I have found that sometimes the impact due to the beating
up of the weft is too strong for the back bearer springs to resist, and where the
back bearer vibrates much to the shedding of the warp I provide a supplementary
arrangement of springs to assist the ordinary back bearer springs at the moment
the beat-up takes place. This part of my invention is shown in Fig. 1 and as will
be seen consists of a rod H at each side of the loom connecting the back bearer to
the slay sword. Each rod is compound. That is to say it is composed of two
principal parts the rod H and the extension H'. The upper end of each rod H
passes loosely through a projecting arm on the back bearer and is provided with
a nut screwed against a shoulder whilst its lower end passes freely through pro-
jections of the extension piece H'. At the upper side of the lower projection '
the rod H is provided with nuts " between which and the upper projection /¹ a
spring is compressed. Further the upper projection / bears against a shoulder
which may be formed integral with the rod or in the form of a nut as shown. The
extension piece H' may be connected with the slay sword in any convenient
manner. prefer to do it by making the piece with a slot which engages with a
stud J fixed to the slay sword. At the extreme end of the piece H' I provide a
set-screw which may be adjusted as desired. These parts are so adjusted that
when the beat-up is taking place the stud J engages with the end of the setscrew j
and causes the spring to be compressed and so assist the back bearer springs to
resist the impact of the blow. When the slay sword retires after the beat-up the
spring- is released allowing the back bearer springs to act without impediment.
Where the back bearer vibrates little to the shedding of the warp,—instead of
using the arrangement described I make use of adjustable stops on the back bearer
brackets as shown in Fig. 7, these stops each consisting of a setscrew K which
bears against a projecting piece K' formed on the back bearer as shown in Fig. 2
and prevents the latter being pulled too far forward at the beat-up of the slay.
The setscrews K are each set about one sixteenth of an inch from the stops K¹
when the pawls 9 of the ratchet mechanism are in gear with the ratchet
wheel 6.
The fourth part of my invention refers to the pawl levers 7 and their actuating
lever 10. Instead of connecting these by a peg and slot arrangement as shown in
my Patent herein before cited I make the engaging portions of them parts of bevil
wheels as shown in Figs. 8 and 9 which are respectively an elevation and plan of

page_text: one pawl lever and an elevation and plan of the lever for actuating the pawl levers.
This improvement permits of a longer stroke of the levers being got and is beneficial
in other ways especially when weaving coarse cloth.
In conclusion I would have it understood that the details of my invention may be
slightly modified without departing from the essential features of the invention as
will be obvious to the practical engineer.
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 ratchet mechanism for automatically letting-off the warp in looms of the
character set forth in my Patent 11,367 of 1892 the use of the improved mechanism
for communicating the motion of the vibrating back bearer to the lever which
controls the pawls substantially as and for the purpose described.
2. In a warp let-off motion for looms of the character set forth the combination
with the ratchet mechanism and a vibrating back bearer of inclined rod A provided
with an arm a to engage with the three armed lever 20, finger C and jaws E
substantially as described and shown.
3. In a warp let-off motion of the character set forth the improved mechanism
for imparting force to the back bearer which gives tension to the warp in a
direction opposite or nearly opposite to the resultant of the warp forces substantially
as and for the purpose described.
4. In a warp let-off motion of the character set forth the supplementary spring
arrangement for preventing the back bearer being pulled forward too much by the
beating in of the weft substantially as described.
5. In a warp let-off motion of the character set forth the use of levers for
actuating the pawls of the ratchet mechanism provided at their engaging parts with
portions of bevil wheels substantially as and for the purpose described.
6. The several improvements in warp let-off motions for looms constructed and
arranged substantially in the manner described and shown in the accompanying
drawings and for the purposes set forth.
Dated this 15th day of December 1893.
RICHARD WILBY,
Applicant.