Improvements in Harness-depressing Devices for Looms.
Year: 1891

page_text: COMPLETE SPECIFICATION.
[Communicated from abroad by GEORGE WILLIAM STAFFORD, of Providence,
Rhode Island, United States of America, Manufacturer.]
Improvements in Harness-depressing Devices for Looms.
I, HENRY HARRIS LAKE, of the firm of Haseltine Lake & Co. Patent Agents,
45 Southampton Buildings, in the County of Middlesex, 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 the devices, sometimes called "spring-jacks," used for
drawing down the heddle-frames or harnesses in looms, after they are raised by the
shedding mechanism. Its object is to vary the effects of the springs that draw the
harnesses down, so as to lessen the strain and wear on the parts that raise them, and
at the same time ensuring their going completely down and staying there until they
are again raised.
Heretofore, one difficulty has been, that where many harnesses were used, and
consequently brought close together one harness in rising was liable to raise another
a little way by the friction of the threads on one another, and between the harnesses,
and so disturb the level position of the warp-threads over which the shuttle passes.
In using springs without the intervention of levers for the purpose of depressing
harnesses in looms, the power exerted by the spring on the harness, increases as the
frame ascends and is at its greatest strength when the harness is up, and the return
of the harness to its lowest or normal position is retarded by the slackening of the
In my spring-
strain of the spring, so as to make its complete descent uncertain.
jack these conditions are reversed, the upward motion of the harness being
facilitated by the slackening up of the spring, and the downward motion accelerated
by the increased pull of the spring through the levers. This is accomplished by so
constructing and arranging the springs and the levers through which they operate
on the harnesses that the strain of the spring shall be at its maximum when the
harness is clear down, and gradually lessened as it rises, until at its highest
position the draft of the spring on the harness will be very light, and put as
little work on the raising mechanism as possible and enable the loom to run at a
higher speed.
Attempts more or less successful have heretofore been made to accomplish these
results, but faults in the construction and arrangement of the parts have stood in
the way of their introduction into general use.
Figure 1 shows a spring-jack embodying this principle, intended for use in cases
where, because of the breadth of the loom or for lack of room under the harness to
make two connections with the harness and bring them to one point to draw down
by, it is necessary to make two direct connections at different points, between the
harness and the jack-lever.
The two side frames AA are placed a proper distance apart according to the
number of harnesses in the loom and the number of jack-levers required, and are
held together by bars B, and the rods D, that support the levers C.
These levers are all of the same shape, but are placed one-half on one of the rods D,
and the other half of them, reversed end for end, are placed on the other rod D,
the two rods being placed at such a distance apart that the teeth of the segment
gear F, on the inner end of one lever, shall engage with the teeth of the segment
In this
gear on the inner end of the lever opposite to it on the other rod D.
position, if the outer part of one lever be moved up or down the outer part of the
opposite lever will be moved in like manner through the segment gears, and by
connecting the two outer ends of the levers to the same harness directly above, that
harness will be drawn down evenly in two places, when the jack-levers are operated.

page_text: 2434
which is the effect desired for the reasons above given.
Figure 3 is a top view of this arrangement. In looms using more harnesses, and
consequently, nearer together, and which will admit of being properly drawn down
by one strap the arrangement shown in Figure 4, is adapted, as twice as many levers
and springs can be made use of in the same space from front to back, than can be
accommodated in the plan of Figure 1, just described.
Figure 4 shows an elevation.
Figure 5, is a top view of the same.
Figures 6 and 7 show the levers separate.
Figure 8 is a vertical section of Figure 5, showing the arrangement of one set of
levers and springs, and
Figure 9 is another similar section showing the arrangement of the other set of
levers and springs.
It is an essential point that each lever should be directly under the harness to
which it is connected, and the whole set of levers should not cover more space from
front to back than the harnesses do in that direction.
Two small upright side frames a, a are placed at a proper distance apart according
to the number of harnesses to be operated, and secured to each other by the cross
bars n, n', which also carry the hooks n", n, that hold the stationary ends of the
springs. There is also placed across the frame a bar o, which is placed under the
long ends of the levers, and the shaft d, in the upper part of the machine, which
serves as a stationary shaft for the levers to swing on. The shapes of the two
kinds of levers used, are shown in Figures 6 and 7 and also in Figures 8 and 9.
The two kinds of levers are placed alternately side by side on the shaft D, every
alternate lever extending out beyond the shaft. Each of the long levers b,
Figure 5, has a close spiral spring e, attached to its short end by means of a
stirrup into which the end of the spring is hooked, while the other end of the
spring is caught over a hook n¹ on the cross-bar n¹. The other levers do not
extend back beyond their hubs on the shaft d, Figure 9, but have hooks j, made on
their under sides, which hold the stirrups 6" into which one end of the springs c¹,
are hooked, the other end being held by the hooks n¹¹, on the bar n.
As will be seen by reference to Figure 5 the springs cc' take up more room
laterally than the levers do, but by making two kinds of levers, and two sets of
springs, and arranging the levers alternately, one half of the room usually occupied
is saved.
An open notch 1 is made in the underside of the free end of each lever to
receive the strap that connects it to the harness. A curved projection 6x cast on
the lower side of cach lever, is to prevent them from overriding one another, when
raised, and a plate or raised portions, is cast on each lever, sufficient to make the
lever at the plate the same thickness as the lever at the hub, to prevent them from
swinging together when they wear a little loose, and so cause the straps to hit each
other and chafe.
By referring to Figures 8 and 9 it will be seen that the levers and spring are so
arranged that when the free end of a lever is raised (see dotted lines) the inner end
of a spring e, or the outer end of a spring c, will be moved toward the shaft d,
bringing the draft on the spring more and more in line with the lever, and the
purchase of the lever will be increased in this way, much faster than the strain
on the spring consequently the higher that end of the lever is raised, the easier it
is moved, and the less it will pull down on the harness. By this arrangement

page_text: the draft on the harness will be least when clear up, increasing as it goes down,
thereby making sure of its going clear down, and staying there until raised again by
the loom.
Of course it is desirable to run the loom with as little down pull on the harnesses
as will work them, as it will require less power and the loom can be run faster.
This strain of the lever on the harness can be lessened by shortening up the strap
that connects it to the harness, so that the lever shall start at a higher point
and work through a higher space, in which, as above shown, the spring will have
less power over it.
Having now particularly described, and ascertained, the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
First. The combination of the side frames A. A, having levers arranged on rods
between them at each end, said levers having segment gears at their inner ends
engaging with each other, substantially as described, and having springs, one to
each pair of levers, with one end attached to the lower bar B, and the other to
the levers as shown, in such manner that as the outer end of a lever is raised, the
direction of the draw on the spring shall come more in a line with the centre of the
lever, as set forth.
Second. The combination with the frames a, cross bars n n' and the shaft d, of a
series of levers 66 placed side by side on said shaft, every alternate lever being
extended out beyond the shaft to receive the connections of an upper series of
springs, and the intermediate levers having catches j, on their under sides between
the shaft d, and their ends to hold connections for a lower series of springs c¹ and
the springs cc said levers being provided with guard plates s, substantially as and
for the purpose set forth.
DJ L 10LL
CML 1001
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.