IMPROVEMENTS IN OR APPLICABLE TO LOOMS FOR WEAVING
Year: 1882

page_text: LETTERS PATENT to James Dawson of Lawiston, Maine, in the United States
of America, but at present residing in Dukinfield in the County of Cheshire
for an Invention of "IMPROVEMENTS IN OR APPLICABLE TO LOOMS FOR
WEAVING."
PROVISIONAL SPECIFICATION left by the said James Dawson at the
Office of the Commissioners of Patents on the 23th August 1882.
JAMES DAWSON, of Lawiston, Maine, in the United States of America, but at
present residing in Dukinfield in the County of Cheshire "IMPROVEMENTS IN
OR APPLICABLE TO LOOMS FOR WEAVING"
This Invention has reference to that class of weft stop mechanism employed in
fancy looms having rising and falling shuttle boxes, and where the apparatus for
detecting the absence or otherwise of weft is fixed about the middle of slay board.
According to my Invention the needles or "feelers" are attached to a rocking
shaft or boss provided with teeth which gear with a rack formed on the top of a
vertical rod.
A
The bottom of the vertical rod is hinged to a counter balanced lever employed
for both raising and lowering the vertical rod and consequently the needles.
series of three adjustable cams are fixed at some convenient place underneath the
breast beam so that as the slay moves to and fro, the forward point of the balance
lever will be operated by the said cams. This balance lever is provided with two
points one employed to raise and depress the needles, and the other for stopping
the loom. The first of the series of cams is used for raising the needles, which cam
is so placed as to raise the said needles while the shuttle is being. sent across the
loom.
The forward point of the balance lever then begins to descend, bringing the
needles with it, but if the weft thread is present it prevents them lowering too far
into a groove cut in the slay board, so that the loom continues to proceed; but if
the weft thread is absent then the needles would lower into the groove, allowing the
points of the balance lever to descend sufficient as for one of its points to reach the

page_text: second cam (which is capable of sliding forward in its bracket) which can it pushes
forward and sets in motion the strap fork mechanism and instantly stops the loom.
The third cam would then be brought into requisition which is used for liberating
the knocking off point of the balance lever from the knocking off cam.
In this class of weft stop mechanism it is found that the woven fabric is indented
or marked by the needles falling upon the thread as each length thereof is sent
across the loom. In order to prevent this I reduce the opening cut in the slay by
placing a grate on the top so that as the weft is sent across, it bears upon the grate
and prevents the needles depressing the warp into the opening which now happens
without the grate.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Dawson in the Great Seal Patent Office on the 28th February
1883.
JAMES DAWSON of Lawiston Maine in the United States of America, but at
present residing in Dukinfield in the County of Cheshire "IMPROVEMENTS IN, OR
APPLICABLE TO LOOMS FOR WEAVING,"
This Invention has reference to that class of weft stop mechanism employed in
fancy looms having rising and falling shuttle boxes, and where the apparatus for
detecting the absence or otherwise of weft is fixed about the middle of slay board.
According to my Invention the needles or "feelers" are attached to a rocking
shaft or boss provided with teeth which gear with a rack formed on the top of a
vertical rod. The bottom of the vertical rod is hinged to a counter balanced lever
employed for both raising and lowering the vertical rod and consequently the
needles. A series of adjustable cains are fixed at some convenient place under-
neath the breast beam, so that as the slay moves too and fro, the vertical rod and
needles will be operated by the said cams. The balance lever is provided with two
points, one employed to raise the needles, and the other for stopping the loom.
One of the series of cams is used for raising the needles, whilst another of the cams
is so placed as to support the said needles while the shuttle is being sent across the
loom. The forward point of the balance lever then begins to descend bringing the
needles with it, but if the weft thread is present, it prevents the needles lowering
too far into a groove cut in the slay board, so that the loom continues to proceed;
but if the weft thread is al sent, then the needles would lower into the said groove,
allowing the points of the balance lever to descend sufficient as for one of its
points to reach the knocking off cam (which is capable of sliding forward in its
bracket) which cam it pushes forward and sets in motion the strap fork mechanism
and instantly stops the loom. Another of the cams would then be brought into
requisition, which is used for liberating the knocking off point of the balance lever
from the knocking off cam.

page_text: "
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In order that my Invention may be better understood, reference is made to the
accompanying Sheet of Drawings which illustrates my improved apparatus in
different positions. Fig. 1 shews the position of the parts when the Lathe or
going part" is at its furthest point backward, Fig 2 shews position of apparatus
just before the lathe has reached its furthest point, Fig 3 shews position of the
parts when the "filling" or weft is present, and the needles have dropped thereon,
allowing the loom to proceed, and Fig 4 is a view of the parts when the "filling
or weft is absent allowing the needle to drop into the groove cut in the slay, and
the dagger in position against the knocking off cam for stopping the loom. A is
the breast beam, B the lathe, and C a bracket employed for supporting the cams or
inclines. D are the needles or weft fork connected to a rocking shaft or boss E
provided with teeth on one side which gear into teeth formed on the top of the
vertical rod F. This rod is capable of sliding up and down in a groove made in
the bracket G secured to the slay. The bottom of the vertical rod F is hinged to a
dagger or counter balanced lever H which is an important factor in this apparatus,
and is employed for both raising and lowering the needles.
A series of cams
I, J, K, L are attached or connected to the bracket G and are respectively employed
for the varied purposes of raising the needles, holding them up until the weft has
been sent across the loom, removing the weight of the needles off the weft
immediately after they have dropped thereon, and for knocking off and stopping
the loom. Hanging from the lever H is a finger M which is so hinged as to remain
rigid in a vertical position when the lathe is receding from the breast beam and
riding over the cam 1 whereby the needles are raised as shewn in Fig 2, but when
the lathe is approaching the breast beam, the finger will give way and ride over the
cam I without raising the needles as shewn in Figs 3 and 4.
I will now describe the action of the apparatus, and will suppose the lathe is
receding from the breast beam. In doing so the hanging finger M would ride up
the cam I, and raise the needles, the backward movement of the lathe would still
continue until the hanging finger M would arrive at the end a of the cam I, when
it would drop off; before doing so however a horizontal peg N projecting from the
lever H would get onto the cam J which is employed for the purpose of holding
the needles up until the shuttle has been sent across the slay. The lathe would
then commence to move towards the breast beam which immediately removes the
peg N off the cam J, allowing the needles and vertical rod F and lever H to fall,
and if the "filling" or weft was present, the needles would fall thereon as shewn in
Fig 3 and prevent the point c of the lever H from lowering too far, thereby keeping
it sufficiently high as to reach the incline of the cam L, up which it rides and by
which it is raised immediately lifting the needles off the weft so that the weight is
removed, and marks or indentations in the weft prevented.
In quick looms I find that the needles D, rod F, and lever H do not drop quick
enough sometimes allowing the point of the lever to pass the cam J and fail
to stop the loom should the "filling" have been absent; to prevent this I place
a flat spring T underneath the lathe behind the lever H as shewn, which will
always operate the parts and bring the needles down immediately after the peg N
has run off the flat part of the cam J. When the "filling" or weft is absent the
needles will drop into the recess cut in the lathe allowing the point c of the lever H
to lower far enough as to reach the flat side of the knocking off cam as shewn in
Fig 4 the force of which would cause the rod O to move in the direction of the
arrow operating the arm P in connection with the strap guide and stop the loom.
A yielding spring R is employed for softening the pressure and force of the rod O,
and S is a spring for bringing the rod and cam back again to their original position.
When the lever H has performed its work, and knocked off the loom by sliding the
cam and rod O in the direction of the arrow it is necessary that it should be
immediately unlatched or released from the said cam and this is effected by another
cam or incline K fixed to the bracket G just behind the cam J. The point of the
lever H is sufficiently broad as to reach both inclines J and K up the latter of
which it rides and lifts the point c out of contact with the flat side of the knocking

page_text: off cam, at the same time raising the rod F and needles D to be realy for the
next shoot of "filling" or weft.
In this class of weft stop mechanism it is found that the woven fabric is indented
or marked by the needles falling upon the "filling," as each length thereof is sent
across the loom. In order to prevent this I reduce the size of the opening cut in
the slay by placing a grate S (shewn in detail Fig 5) on the top so that as the
weft is sent across it, bears upon the grate and prevents the needles depressing the
warp into the opening which now happens without the grate.
Having now shewn and described my Invention, and the manner of carrying the
same into practice, I would remark that I am aware some of the parts herein shewn
and described are not new, as they have been in use both in Great Britain and in
the United States of America for some time I therefore do not claim all the parts
herein shewn and described what however I consider to be new and claim is
First. The use and employment of the knocking off cam J when employed for
the double purpose of knocking off, when weft is absent, and for immediately
raising the weight of the needles off the "filling" when it is present by the point
of lever H riding up the inclined part of the said cam in manner substantially as
herein shewn and described
Second. The use and employment of the incline or cam for releasing or
unlatching the point of the lever H from contact with the knocking off cam J
whereby the said lever is allowed to ride up the incline of cam J, and so raise the
needles into an upright position, substantially as shewn and described.
Third. The use and employment of the balance lever H when provided with two
points, one of which is employed to raise the needles and the other for stopping
the loom substantially as herein shewn and described.
Fourth. The use and employment of the grating S for the purpose substantially
as described.
Fifth The use of the spring T for causing the needles to be lowered as soon as
they are set at liberty as described.
Sixth. In combining with, and in connecting to the dagger H a swinging
finger M so arranged as to drop off the end of its lifting cam I, and allowing the
peg N to fall onto the cam J whereby the needles are partially let down as
described.
In witness whereof I the said James Dawson have hereunto set my hand
and seal this Twenty fourth day of February in the year of our Lord, one
thousand eight hundred and eighty three.