IMPROVEMENTS IN WARP OR STRAIGHT BAR KNITTING MACHINES AND IN THE FABRIC PRODUCED THEREON.”
Year: 1881

page_text: LETTERS PATENT to Walter Dexter, of the Town and County of the Town of
Nottingham, for an Invention of "IMPROVEMENTS IN WARP OR STRAIGHT
BAR KNITTING MACHINES AND IN THE FABRIC PRODUCED THEREON.”
PROVISIONAL SPECIFICATION left by the said Walter Dexter at the Office
of the Commissioners of Patents on the 13th October 1881.
WALTER DEXTER, of the Town and County of the Town of Nottingham.
"IMPROVEMENTS IN WARP OR STRAIGHT BAR KNITTING MACHINES AND IN THE
FABRIC PRODUCED THEREON."
My improvements in warp or straight bar knitting machines are as follows:-
The machine consists of two standards and a middle support firmly held together
by two bottom and one top tie bar. The top tie bar also forms a bearing or rest
for a needle bar to slide upon. A main driving shaft running the whole length of
the machine is carried in bearings secured to the standards and middle support,
upon which are keyed cams or eccentrics which work against trucks, and thereby
give motion to a frame connected with the needle bar, thereby moving the needle
bar backwards and forwards. The needles are attached to the needle bar in the
usual manner, but with their latches downwards, and in their movement pass
through a series of knocking over bits formed of small pieces of flat steel placed at a
distance apart corresponding with the gauge of the needles, and united together by
an alloy in a similar manner to the needles. The knocking over bits are fixed to the
front edge of the top tie bar, and in front of the needle bar. The needles used are those
known as "tumbler or "latch" needles. In front of the needle bar, and parallel
with it, are placed stop and division guides or points and thread guide bars working
in bearings provided for them. The thread guide bar has imparted to it a rocking
motion by a can on the main driving shaft connected by a slide frame and con-
necting rod with a lever on the thread guide shaft, the movement given being
sufficient to clear the top and bottom sides of the needles. The thread guide shaft
also has a lateral motion given to it by a cam on a cross shaft revolving in bearings
which are secured to the standard; this cross shaft is made to revolve by bevel,
n
"

page_text: mitre, or worm gear, or otherwise, as required, from the main driving shaft. The
cam is formed in such a manner that it shall give more or less travel to the thread
guide shaft, as shall be determined upon, whether it be required to travel the
distance of one, two, three, or more needles and back again. Motion is given to
the thread guide shaft by the said cam giving motion to a lever which acts against
the end of the thread guide shaft, and is connected in such a manner that it shall
move the thread shaft backwards and forwards endwise. It will here be noticed
that the two distinct motions given to the thread guide bar will cause the thread
guides, which are small pieces of steel with a slot at one end through which the
threads pass, and which are fastened to the thread guide bar by a metal alloy, as
is the case with the needles, to describe a circuitous path around the needles. The
actions are simultaneous, and are performed when the needle bar is at its extreme
forward position. The thread guides are also provided with a second hole a short
distance from the slot just mentioned, through which second hole is passed a wire
which serves as a guide for a second thread, as described hereafter. Between the
needle bar and the thread guide shaft is placed the stop and division guide or point
shaft, which is carried in bearings in a similar manner to that above described for
the thread guide shaft, and is parallel with the needle bar. The stop guides and
division guides or points consist of small flat pieces of angular shaped steel fixed
to the stop guide and division shaft by an alloy, as is the case with the needles;
this shaft has a rocking motion imparted to it in a similar manner to that above
described for the thread guide shaft. When the shaft rocks upwards the stop and
division guides or points pass between the needles, and remain in that position
until the needle bar has travelled from its backward to its forward position, and
'then recede below and out of the way of the needles; their duty is to prevent the
fabric from coming forward with the needles and to inlay an additional thread,
which passes under the wire in the second hole in the thread guide, thence under a
wire or rod carried by the alloy of the stop or division guides or points, and
through a hole in the end of the said guides or points to the work. The material
for the loops and for the inlay threads is taken from warp beams or from spools, as
in the case of the ordinary warp or straight bar knitting machines. The threads
after leaving the beams or spools pass through a sley attached to the upper part
of the standard, after which they pass over a smooth rod or beam through the
guides, which place or wrap them round the needles to form the new loops. The
winding up is performed in the usual way by rollers and friction bands, and
weights.
The wire or rod of the stop or division guides or points also acts as a stop for
the latches to prevent their rising when the thread is being lapped around the
needles.
My second improvement consists of the introduction of a second thread inter-
woven between the stitches or loops of the needle thread, which gives a rigidity to
the fabric produced without any reduction of the speed of the machine. These
threads are passed under the fixed wire or rod in the second holes in the thread
guides heretofore described for the purpose of preventing them from getting
entangled with the machinery, and thence underneath a similar wire or rod
fastened in the alloy metal of the stop and division guides or points, and thence
through the hole in the stop and division guides or points, as before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Walter Dexter in the Great Seal Patent Office on the 13th April
1882.
WALTER DEXTER, of the Town and County of the Town of Nottingham.
"IMPROVEMENTS IN WARP OR STRAIGHT BAR KNITTING MACHINES AND IN THE
FABRIC PRODUCED THEREON."
:-
My improvements in warp or straight bar knitting machines are as follows:-
The machine consists of two standards and a middle support firmly held
together by two bottom and one top tie bar. The top tie bar also forms a bearing
or rest for a needle bar to slide upon.
A main driving shaft running the whole length of a machine is carried in
bearings secured to the standards and middle support, upon which are keyed cams
or eccentrics which work against trucks and thereby give motion to a frame
connected with the needle bar, thereby moving the needle bar backwards and
forwards. The needles are attached to the needle bar in the usual manner but
with their latches downwards, and in their movement pass through a scries of
knocking over bits formed of small pieces of flat steel placed at a distance apart
corresponding with the gauge of the needles, and united together by an alloy in
a similar manner to the needles. The knocking over bits are fixed to the front
edge of the top tie bar and in front of the needle bar. The needles used are those
known as "tumbler" or "latch" needles. In front of the needle bar and parallel
with it are placed stop and division guides or points and thread guide bars working
in bearings provided for them. The thread guide bar has imparted to it a revolving
motion by a cam on the main driving shaft, connected by a slide frame and
connecting rod with a lever on the thread guide shaft, the movement given being
sufficient to clear the top and bottom sides of the needles.
The thread guide shaft also has a lateral motion given to it by a cam on a cross
shaft revolving in bearings which are secured to the standard. This cross.shaft is
made to revolve by bevel, mitre, or worm gear, or otherwise as required, from the
main driving shaft. The cam is formed in such a manner that it shall give more
or less travel to the thread guide shaft as shall be determined upon, whether it be
required to travel the distance of one, two, three, or more needles and back again.
Motion is given to the thread guide shaft by the said cam giving motion to a lever
which acts against the end of the thread guide shaft, and is connected in such a
manner that it shall move the thread guide shaft backwards and forwards endwise.
It will here be noticed that the two distinct motions given to the thread guide bar
will cause the thread guides, which are small pieces of steel with a slot at one end
through which the threads pass, and which are fastened to the thread guide bar
by a metal alloy, as is the case with the needles, to describe a circuitous path
around the needles. The actions are simultaneous, and are performed when the
needle bar is at its extreme forward position.
The thread guides are also provided with a second hole a short distance from the
slot just mentioned, through which second hole is passed a wire which serves as a
guide for a second thread as described hereafter. Between the needle bar and the
thread guide shaft is placed the stop and division guide or point shaft, which is
carried in bearings in a similar manner to that above described for the thread
guide shaft and is parallel with the needle bar. The stop guides and division
guides or points consist of small flat pieces of angular shaped steel fixed to the stop
guide and division shaft by an alloy, as is the case with the needles. This shaft
has a rocking motion imparted to it in a similar manner to that above described

page_text: for the thread guide shaft. When the shaft rocks upwards the stop and division
guides or points pass between the needles, and remain in that position until the
needle bar has travelled from its backward to its forward position, and then
recede below and out of the way of the needles. Their duty is to prevent the
fabric from coming forward with the needles and to inlay an additional thread
which passes under the wire in the second hole in the thread guide, thence under
a wire or rod carried by the alloy of the stop or division guides or points, and
through a hole in the end of the said guides or points to the work.
The material for the loops and for the inlay threads is taken from warp beams
.or from spools, as in the case of the ordinary warp or straight bar knitting
machines. The threads, after leaving the beams or spools, pass through a sley
attached to the upper part of the standard, after which they pass over a smooth
rod or beam through the guides which place or wrap them round the needles to
form the new loops. The winding up is performed in the usual way by rollers and
friction bands and weights.
The wire or rod of the stop or division guides or points also acts as a stop for the
latches to prevent their rising when the thread is being wrapped around the
needles.
My second improvement consists of the introduction of a second thread inter-
woven between the stitches or loops of the needle thread, which gives a rigidity
to the fabric produced without any reduction of the speed of the machine. These
threads are passed under the fixed wire or rod in the second holes in the thread
guides heretofore described for the purpose of preventing them from getting
entangled with the machinery, and thence underneath a similar wire or rod
fastened in the alloy metal of the stop and division guides or points, and thence
through the hole in the stop and division guides or points as before described.
And in order that my said Invention may be more clearly understood and
readily carried into effect, I will proceed, aided by the accompanying Drawings,
more fully to describe the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is an end elevation; Figure 2 is a cross section; and Figure 3 is a plan
of parts of a warp or straight bar knitting machine with my improvements applied
thereto; Figures 4, 5, and 6 are full size views of the instruments showing some
of the positions assumed thereby in work; and Figures 7, 8, 9, 10, and 11, are face
views of the various cams employed in communicating motion to the working
instruments; Figure 2 represents the parts in a slightly different position from
that shewn at Figures 1 and 3, and Figures 7, 8, 9, 10, and 11 shew the cams in
corresponding position to that shown at Figure 2.
a, a, are the end standards; a¹ is the centre support. The standards a, a, and
centre support a' are connected together by two bottom tie bars (not shown) and
a top tie bar b, which latter serves also as a bearing for the needle bar c, to
which are fixed frames c¹ carrying the trucks or rollers c², c³, which are operated
by the cams or eccentrics d.
Two, three, or more of these frames c¹ are used according to the length of the
machine. The cams or eccentrics & through the trucks or rollers c², c², and frames c¹
give a to and fro motion to the needle bar c. The cams or eccentrics d are fixed
on the main driving shaft e on the end of which is fixed a bevel pinion e¹ gearing
into a bevel wheel f' fixed on one end of the cross shaft f, on the other end of
which are fixed the cams g and h which give the necessary lateral motions to the
thread guide shaft i and to the stop and division guide shaft j. The cross shaft f
is carried by the brackets a², a³ ³,³, are the needles which are cast in leads c
with their latches downwards, and are fixed to the needle bar c. The needles* in
their movement pass through a series of knocking over bits k, k, formed of small
pieces of flat steel placed at a distance apart corresponding with the guage of the
needles and united together by an alloy in a similar manner to the needles.

page_text: The knocking over bits k, k, are fixed to the front edge of the top tie bar b and
in front of the needle bar c.
In front of the needle bar c and parallel with it are placed thread guides 1, 1,
and stop and division guides or points m, m, which are fixed respectively to
bars l', m', which work in bearings provided for them. The thread guide bar
has imparted to it a rocking motion by a cam n on the main driving shaft e acting
upon trucks or rollers 12, 1, carried by slide frames ³ connected to the bar by
connecting rods and levers 1 fixed on the bar , the movement given being
sufficient to clear the top and bottom sides of the needles.
The thread guide shaft or bar l'also has a lateral motion given to it by the cam g,
which is formed in such a manner that it shall give more or less travel to the thread
guide shaft or bar l, as shall be determined upon, whether the thread guides
are required to travel the distance of one, two, three, or more needles and back
again.
Motion is communicated to the thread guide shaft or bar by the cam g giving
motion to a lever g', which acts against the end of the thread guide bar l', and is so
connected thereto that it shall move the thread guide bar l' backwards and forwards
end wise as required. By these means two distinct motions are given to the thread
guide bar , which will cause the thread guides 1, 1, to describe a circuitous path
around the needles. The actions are simultaneous, and are performed when the
needle bar c is at its extreme forward position.
The thread guides L, l, are also provided with a second hole, through which is
passed a wire which serves as a guide for a second thread, as hereafter
described.
The stop and division guide or point bar m³ is placed between the thread guide
shaft or bar and the needle bar c, and is carried in bearings in a similar manner
to the thread guide bar l', and is parallel with the needle bar c. The stop and
division guides or points m consist of small flat pieces of angular shaped steel, as
shown. This shaft or bar m' has a rocking motion imparted to it by the cam h
acting upon the trucks or rollers m² carried by slide frames m³ connected to the
bar m' by connecting rods m* and levers m³ fixed on the bar m'. When the shaft
or bar m¹ rocks upwards the stop and division guides or points m pass between the
needles c³, and remain in that position until the needle bar c has travelled from its
back ward to its forward position, and then recede below and out of the way of the
needles ; their duty is to prevent the fabric from coming forward with the needles
and to inlay an additional thread, in the manner hereinafter described. The material
for the loops and for the inlay threads is taken from warp beams 8 and o or from
spools, as in the case of the ordinary warp or straight bar knitting machines. The
threads from the warp beam s pass through a sley p, over the smooth rod or beam q,
under the wire 16, through the slot in the guides 7, which place or wrap them around
the needles to form the new loops. My second improvement consists of the
introduction of a second thread interwoven between the stitches or loops of the
needle thread, which gives a rigidity to the fabric produced without any reduction
to the speed of the machine..
These straight threads pass from the beam o, then between the two bars or
shafts l', m', under the wire or rod to, then under the wire or rod me, and through
the hole m' in the stop guides and division bits m to the work. The wire or rod m³
also acts as a stop for the latches of the needles to prevent their rising when the
thread is being lapped around the needles.
The machine operates in the following manner-In starting the machine with
the needle bar c nearly at its forward position the thread guides I, I, are caused to
move in a lateral direction, as desired, the distance of one, two, or more needles c³
by the cam g. The thread guides 1, l, are then rocked, and thereby caused to pass
between the needles by the action of the cam n. On arriving at the bottom of
their motions they are again caused to move by the cam g in a lateral direction the
distance of one, two, or more needles, and then by the cam m are again rocked and
brought back into their first position, thus passing up between different needles.

page_text: By these means the guides 7, 1, will have placed the threads round the needles c³.
During this time the needle bar c¹ has only made a small part of its movement
backward. The stops and division guides m, m, now rock, and thereby recede
below the needles c³, being operated by the cam g, when they receive a lateral
movement the distance of one, two, or more needles, which is given to them by the
cam n, after which they pass up again through the needles c³, and remain in that
position until the needle bar c has made its forward motion. By these means the
straight thread will have become interwoven with the other threads; the stop and
division guides m, m, also prevent the work coming forward with the needles c³.
Having thus described the nature of my said Invention, and the mode in which
I carry the same into effect, I would have it understood that I do not claim the
arrangement of parts ordinarily employed in warp or straight bar knitting machines,
but what I do claim is,-
First. The peculiar arrangement and mode of operation of warp or straight bar
knitting machinery, substantially as herein shown and described and for the purpose
stated, and,
Second. The introduction into fabric produced on a warp or straight bar knitting
machine of an additional or second thread interwoven between the stitches or loops
of the needle thread, whereby a rigidity is given to the fabric produced, substantially
as herein described.
In witness whereof, I, the said Walter Dexter, have hereunto set my hand
and seal, this Eighth day of April, One thousand eight hundred and eighty
Signed, sealed, and delivered by
the above named Walter Dexter,
in the presence of
G. L. COWLEY,
A Commissioner to Administer Oaths
in the Supreme Court of Judicature
in England.
WALTER DEXTER. (L.S.)