Improvements in Circular Knitting Machines.
Year: 1893

page_text: Date of Application, 21st Oct., 1893
Complete Specification Left, 21st July, 1894-Accepted, 1st Sept., 1894
PROVISIONAL SPECIFICATION.
Improvements in Circular Knitting Machines.
1, WILLIAM INGRAM JAMES, of Green End House Stafford, in the County of
Stafford Engineer do hereby declare the nature of this invention to be as
follows:-
a
My invention consists in an improved form of device for holding down the web
as it is produced by the needles of a circular knitting machine. I provide
series of sinker bits working in horizontal grooves formed in the upper part of
the needle cylinder.
These sinker bits are made with a hook formed upon them for the purpose of
preventing the knitted web being lifted by the knitting needles as they are raised
by the knitting-cams.
I also provide suitable mechanism, controlled by some convenient revolving
part of the machine, for the purpose of imparting to the sinker bits a to and fro
movement to enable the yarn to come properly under the hooks of the
sinker bits.
Instead of causing the sinker bits to slide in horizontally placed grooves I may,
if preferred, give them the forin of vertical levers, pivoted at any convenient point
of their length to some fixed part of the machine and guided at their two ends in
suitably formed grooves, and, by conveniently arranged mechanism, controlled by
some revolving part of the machine, impart to them an oscillating movement for
the purpose of causing the yarn to lie properly under the hooks formed in the
upper ends of the sinker bits.
1000
W. INGRAM JAMES.
COMPLETE SPECIFICATION.
Improvements in Circular Knitting Machines.
I WILLIAM INGRAM JAMES, of Green End House, Stafford, in the County of
Stafford, Engineer 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 consists of an improved form of hold down for holding down the
work as it is produced by the needles of a circular knitting machine and is equally
applicable to machines which are made to produce what is known as plain web and
to those which produce ribbed web.
In one form of my invention I make the needle cylinder with grooves for
carrying the needles as usual but at its upper part I make it of a diameter equal
to that measured from the bottom of one needle groove to the bottom of the
needle groove directly opposite. The result of this is that the upper part of the
cylinder will not have the usual "needle posts over which the needles draw
the yarn to form the stitch.
"
On the inside of the upper part of the needle cylinder I form a thickening of
the walls of the cylinder either by making the cylinder itself thicker or by inserting
a ring inside the top of the cylinder.
Through this thickened part I cut a series of horizontal or slightly inclined
grooves running radially towards the axis of the cylinder. These radial grooves

page_text: are equidistant one from the other and equal in number to the needle grooves
and so arranged that between and above each pair of needle grooves there shall
be one radial groove. The radial grooves are cut to such a depth as to leave
a thickness of metal between the bottom of the radial grooves and the under-
side of the thickening of the cylinder top. In each groove I provide a "sinker
bit," which slides freely in the groove, so shaped that it forms the " post
over which the needle draws the yarn to form the stitch and the "sinker bit"
has a hook formed on it over the part which serves as a post "in such manner
that when the yarn is drawn by the needle over the "post" it lies underneath
the hook of the "sinker bit" and as the needle is raised by the action of the
needle cams the yarn is held by this hook and prevented from rising with the
needles. In ribbing machines I make the hook of the "sinker bit" of such a
shape as to allow the ribbing needles to pass freely over the tops of the hooks.
At the time that the knitting needles are drawing down the yarn to form the
stitch it is desirable that the hook of the "sinker bit" should be moved slightly
outwards from the axis of the needle cylinder and returned as soon as the needle
begins to rise.
To accomplish this I provide a cam attached to any convenient revolving part
of the machine which engages a notch formed in the "sinker bit" and actuates the
same at the proper moment.
To prevent the "sinkers" being lifted by the yarn as the needles rise I provide
a retaining ring in the upper part of the cylinder.
In an alternative form of my invention I do not thicken the upper part of the
cylinder and I make the grooves for the "sinkers" vertical.
At a suitable height on the cylinder I form a horizontal groove and I make the
"sinkers" in the form of vertical levers with a pivot near the centre of their length
which engages the groove and serves as a fulcrum.
"
The upper ends of the "sinkers" serve as "posts and are provided with
holding down hooks as before and the lower ends are provided with tails which
are operated by a cam carried in the cam shell of the machine.
An annular spring is provided at the upper ends of the "sinkers" which draws
their hooks inwards when not held out by the action of the cam.
My invention is illustrated by the accompanying drawings in which :-
Fig. 1. is an elevation and Fig. 2. a plan of a portion of a circular reversible
knitting machine shewing my improvements.
Fig. 3. is a vertical section through one side of the needle cylinder shewing one
of the "sinker bits."
Fig. 4. is a vertical section, Fig. 5. an elevation and Fig. 6. a horizontal section
shewing an alternative construction.
A circular reversible knitting machine of a usual construction has certain of its
parts, which it will be necessary to refer to in the description of my present
invention, arranged and operated in the following manner :-
A is the needle cylinder supported in the machine in the usual manner and
provided with the grooves B for the cylinder needles C which move vertically
therein and are operated by suitable cams provided for the purpose in the cam
shell D which is revolved in either direction as desired around the cylinder A by
means of an ordinary gear ring. Upon this gear ring is carried the usual driver É
and yarn carrier post F. The driver E engages at its ends G. H. with one or other
(according to the direction of revolution) of the driving lugs I. J. which are
provided upon the cam shell D.
By this well known method of driving the cam shell D the necessary lead which
the yarn carrier should bave in advance of the needle stitch cam (the centre of
which is indicated on the drawings by the line K) is ensured by allowing an
interval of space between the lugs I and J greater than the length of the driver E
which extra space has to be traversed by the driver E and yarn carrier post F,
whenever the machine is reversed before the said driver E can engage either of
the lugs 1 or J so as to communicate movement to the cam shell D.

page_text: will now proceed to describe my invention :-
-
For the purpose of holding down the knitted web as it is produced by the
machine I provide a series of "sinker bits" a which I mount so that they are free
to slide in either horizontal or slightly inclined radial groves b formed in the upper
edge of the needle cylinder A. These "sinker bits a are made with a hook c
formed upon them for the purpose of preventing the knitted web being lifted by the
operation of the cylinder needles C. The inner portion d of the "sinker bit "
projects under a retaining ring e which is provided within the upper part of the
cylinder A to keep the "sinker bits" in their places. A stop fis provided on
each "sinker bit" which takes against the lip g of the ring e when the "sinker
bit is in its extreme outward position and strikes against the angle of the ring
when the "sinker bit" is in its innermost position.
"
So that the "sinker bits " may be operated I provide them with tails in which
are formed notches ; which are engaged by a cam k carried upon a curved piece /
which is mounted upon the cam shell D. The cam k is of such a shape as will
give to the "sinker bits" when the machine is revolved an outward and inward
movement just in advance of the point where the stitch cam draws down the
cylinder needles and by this means the hooks c are enabled to engage and hold down
the knitted web.
In the drawings the machine is represented as revolving in the direction shewn
by the arrows and it will be observed that the operating portion m of the cam k is
leading or in advance of the line K which represents the centre of the needle stitch
cam. Now when the machine is reversed it is necessary that this lead of the sinker
cam m should be changed also so as to take effect to the left hand instead of to the
right as the drawings shew it and in order that this may automatically take place
I mount the piece upon the cam shell D by means of screws n which pass through
rollers n, in the slots o in the piece / so as to permit of the latter being moved.
circumferentially upon the cam shell D.
This circumferential movement is produced (in one or the other direction as the
case may be) by providing lugs p and q upon the piece which are engaged by the
yarn carrier post F, preferably by the intervention of set screws rands for
the purpose of adjustment.
The distance traversed by the post F between the screws r and s when the
machine is reversed is less, by twice the amount by which the cam m leads the
stitch cam, than the distance traversed by the cam shell driver E between
the lugs 1 and J previously referred to so that the piece is moved upon the cam
shell D and the necessary lead given to the cam m before the cam shell itself is set
in motion.
In the alternative construction shewn in Figs. 4. 5 and 6 the "sinker-bits" a¹
are arranged around the cylinder A¹ in vertical grooves 6' and are in the form of
levers pivoted on points t in a groove u formed in the needle cylinder A'. The
upper ends of the "sinker bits" are drawn inwards by a circular or bracelet
spring which engages the notches w formed in the "sinker-bits" for the purpose
and the "sinker bits' are operated by a cam m¹ carried in the cam shell D₁ which
engages the tails i¹ formed on the "sinker bits
for the purpose.
"
In order to change the lead of the operation of the "sinker bits" when the
machine is reversed the cam m¹ is made double ended and mounted on a pivot x in
the cam shell D¹. The end m² is thrown into action when the machine is revolving
in the direction shewn by the arrow and the end m³ when the machine is reversed
thus. The driver E¹ has formed in it a plain horizontal circular groove y at one
end of which and occupying about half of its depth is formed a cam y' and at the
other end occupying about the other half of its depth is formed a cam y². The
cam m has a projection m which is engaged by the cam y2 so as to throw the end m³
into operation when the machine is revolving as shewn by the arrow and a
projection which is engaged by the cam y₁ so as to throw the end m³ into
operation when the machine revolves in the opposite direction. The projection m⭑
and the cam y2 are above the projection m³ and the cam y' so that each acts

page_text: independently of the other and the ends H and G of the driver E¹ engage the
lugs I and J of the cam shell D' respectively at the same times that the
cams y and y engage the ends m* and m of the cam m'.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is:
"
1. The herein described and illustrated "sinker bits a constructed and operated
in the manner shewn and for the purpose set forth.
2. The retaining ring e as described and illustrated and for the purpose set
forth.
"
3. The cam k with the curved portion m for operating the "sinker bits as
herein described and illustrated.
4. The piece mounted upon the cam shell so that it is capable of being moved
circumferentially thereon in the manner stated and for the purpose set forth.
5. The herein described and illustrated method of driving the piece I and cam k
by which when the machine is reversed the lead of the cam k is reversed prior to
the reversal of the cam shell.
6. The method of holding down the knitted web, as it is produced upon a
knitting machine, as herein described and illustrated in Figs. 1. 2 and 3.
7. The "sinker bits" a' constructed and operated in the manner shewn and for
the purpose set forth.
8. The cam m' pivoted in the cam shell and operated by the driver as described
and illustrated and for the purpose set forth.
9. The method of holding down the knitted web, as it is produced upon a knitting
machine, as herein described and illustrated in Figs. 4. 5 and 6.
Dated this 20th day of July 1894.
W. INGRAM JAMES.