IMPROVEMENTS IN WARP KNITTING MACHINES
Year: 1885

page_text: COMEDUIM DE CULTIVATION
"
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
63, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN WARP KNITTING MACHINES (a communication to me from abroad by La
Société A Roux et Cie, of Courbevoie near Paris, France Manufacturers) 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 an improved warp knitting machine more especially
intended for the manufacture of the special kind of looped or knitted fabrics in
which a nonextensible weft thread is laid through each row of loops and which
are known as fixed weft knitted fabrics, the improvements relating to mechanical
arrangements whereby the construction and action of the machine is simplified and
more especially to the arrangements for passing a weft thread between two thread
guide bars as hereafter described.
By means of these improvements the machine can be made to produce fabrics
having patterns in relief by providing for each of the two thread guide bars a
pattern disc or wheel furnished with adjustable tappets which are caused to project
in any desired order from the periphery, for the purpose of producing the pattern.
Another feature consists in the employment of a device whose functions resemble
those of the shuttle of a loom and by which at each throw a nonextensible weft
thread is deposited for the purpose of depriving the knitted fabric of its usual
elasticity.
The machine is furnished with knitting needles so formed that the shogging
action of the needle guides cannot in any case cause the breakage of the thread as
will be hereafter described.
Reference is to be had to the accompanying drawings the principal views in
which represent that half of the machine only which comprises the warp knitting
mechanism proper, the end of the machine at which the driving gear is situated
being omitted. Figure 1 is a front view, Figure 2 an end view and Figure 3 a
back view of the machine. Figure 4 is a part section on line 1. 2 Figure 3:
Figure 5 is a detail plan view of the gear for operating the thread guide bars.
Figure 6 shows on a larger scale, the detail of one of the pattern discs. The same
letters of reference indicate the same parts in all the figures.
As the accessory parts of the machine are very similar to those of ordinary
straight bar knitting machines I will here describe only those parts to which the
more important improvements are applied, a is the main shaft which by means

page_text: of the bevel gear drives a cam c formed on or attached to hevel wheel b. This
cam c operates the weft laying device above referred to through a lever d pivoted
at e to the machine frame and connected at its slotted lower end with a rod
terminating in a rack which gears with a pinion g whose shaft, mounted at the
lower back part of the machine. carries a pulley h round which is passed a crossed
belt for producing the to and fro motion of the carriage or weft laying device.
The belt passes from the pulley around an inclined guide pulley j at each end of
the machine and is attached at the ends to the carriage as clearly shown in
Figure 1. By this means the carriage will be caused at every revolution of the
cam c to move across the machine from right to left and then back from left to
right upon the rail or race l.
It is preferred to effect the stoppage of the warp knitting mechanism during the
time the nonextensible weft thread is being laid, without throwing it out of gear,
by employing single acting cams whose dead points (which correspond to the
period of rest of the warp knitting mechanism) are situated at the second half
of their circumference which would otherwise be used for producing the double
action.
The weft laying arm has a stud n which at each traverse engages with a
latch m (Figure 3) provided with a too p whereby it is raised to release the weft
laying device at the proper moment for laying its weft thread, this disengagement
being produced by an incline carried on a rod e, which receives a longitudinal
movement in the one direction from a bellcrank lever s carrying a truck roller t
and actuated by a cam a mounted upon the intermediate cross shaft v, and in the
other direction by a spring. A similar mechanism is placed at the other end of
the machine for the same purpose, the said mechanisms being fixed at any suitable
point of the rail for limiting the movement of the carriage as desired. The
needles are separated by the sinkers x mounted on a bar z. The needles are fixed
in the needle bar 1 Figure 4, and in order to prevent the thread guides in their
shogging motion from catching the wool by advancing too far over the hook of the
needle and thus breaking the thread, the hook is considerably increased in length
and the pivot of the latch placed further back. By this arrangement the eye of
the thread guide will not project beyond the extremity of the hook and prevents
the breaking of the thread by protecting it.
Figure 4 shows the manner in which the motion, by which the loops formed are
pushed back by means of the sinkers c, for the purpose of forming fresh loops is
produced This motion is produced by the oscillation of the sinker bar z on joint 2
as an axis by means of the cam 3 (Figures 3 and 4) acting on levers 4 oscillating
on the longitudinal shaft 5. A second motion imparted to bar z produces the
knocking over of the loops, which as shown in Figures 3 and 4 is effected by the
cam 6 acting on levers 7 connected to the lower part of the bar z by the arms 8.
In this machine two thread guide bars are employed placed one above the other
and the two rows of thread guides being consequently superposed. The shogging
motion of each of said bars for laying the thread upon the needles is produced by
means of a pattern wheel 10 separately represented in Figure 6. Each face of the
wheel has a suitable number of radial grooves in which the tappets / slide, the said
tappets and the corresponding face of the wheel being graduated to allow of their
being adjusted to project more or less from the periphery of the disc according to
the pattern of fabric to be produced each graduation corresponding to the passage
of the thread guide over one needle.
The tappets are adjusted by screws 12 which bear against the wheel boss and
are fixed in position by nuts 13.
Each wheel 10 having a proper number of tappets projecting acts on the truck
roller 14 (figure 5) of an arm p 15 connected by a rod 16 to a thread guide bar.
17 18 are springs for returning the bars to position the springs being attached to a
double hook 19 on the machine frameing. The horizontal to and fro movement of
the thread guide bars is imparted by the cam 34 (figure 3) and their upward move-
ment by the levers 35 by causing their support 36 to oscillate on axis 37 (figure 2)

page_text: and two thread guide bars are here shown but their number may be increased by
increasing the number of pattern wheels, 20, 21 are guides for the two thread guide
bars. The pattern wheels 10 are actuated by the ratchet wheels 22 which are
connected thereto in any suitable manner, the whole turning freely on shaft v.
Figure 2 shows more particularly the manner in which this motion is produced.
The ratchet wheel 22 is operated by two pawls 23, 24 connected by a spring 25
and having two different centres of oscillation. The pawl 24 (figure 1) is pivoted
at 26 to the end of an arm which itself pivots upon a short shaft 27, while the
pawl 23 pivots on a fixed pin 28. The pawl 24 turns the wheel 22, for which
purpose the shaft 27 carrying the arm 26 has a lever 29 keyed on its end carrying
a friction roller 30 upon which act cams 31 two in number fixed on a disc 32
keyed on shaft which at each revolution produces two oscillations of shaft 27 and
consequently moves the ratchet wheel 22 two teeth; the pawl 23 serving to
prevent the return motion of the ratchet wheel. In order to further ensure the
absolute fixity of the ratchet after each movement, a brake or other suitable
arrangement would be employed to prevent any backward movement. The double
movement may however be varied to suit the requirements of the work. The
cam 39 works the ratchet 40 of the work beam through the jointed levers 41. The
warp threads pass from roller 42 to the thread guides, being led over a guide
rod 43 corresponding to each bar. The bar 38 which extends the entire length of
the machine is intended to enable the operative to throw the driving gear out of
action from any point.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is
"
1. A warp knitting machine having two thread guide bars for forming knitted
fabrics with a fixed" weft in combination with a device for depositing a weft
thread in each row of stitches as described for the purpose specified.
2nd In a warp knitting machine for forming knitted fabrics with a fixed weft
an apparatus for depositing a weft thread for each row of stitches moved from right
to left and left to right upon a race by a cord i wrapped around a drum receiving
alternate motion from a rack bar factuated by a lever d and cam c as shown and
described.
3rd The mechanism for arresting the weft laying device consisting of a latch m
which is released by an incline q on a rod receiving longitudinal to and fro
movement from a bell crank levers and cam u as shown and described.
4th In a warp knitting machine for making knitted fabrics with a fixed weft,
the arrangement of two thread guide bars to which a shogging motion for laying
the threads upon each needle is imparted and regulated by means of pattern wheels
having radially adjustable tappets for varying the pattern of the fabric produced,
said wheels receiving motion from ratchet gear operated by a cam as shown and
described.
5th The knitting needles having elongated hooks and the latches set back in
order to prevent the interference of the thread with the movement of the thread
guides as described.