Im- PROVEMENTS IN SEWING MACHINES
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Charles Tiot Judkins at the Office
of the Commissioners of Patents, with his Petition, on the 9th August
1866.
I, CHARLES TIOT JUDKINS, of 4, Ludgate Hill, in the City of London,
Manufacturer, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN SEWING MACHINES," to be as follows:-
My Invention consists first in the combination or arrangement of parts
of sewing machines as hereafter described for producing the chain stitch;
and, secondly, in the employment of a rack arranged and acting as hereafter
described.
Upon a horizontal shaft beneath the bed plate of the machine, and driven
by the ordinary pulley or hand wheel I mount two grooved cams, in the groove
of one of these cams a pin on one end of a bell-crank lever rides, the other
end of this lever being connected to the needle slide; as this cam rotates
with the shaft the lever imparts the up-and-down motion to the needle slide.
The parts of the machine just referred to are the same as in what is known
as the Lancashire machine, and are fully described in the Specification of
Letters Patent granted to Edward Joseph Hughes, on the 10th August 1852,
No. 14,256. In the groove of the other cam a pin or projection upon a
horizontal rod rides, so that the rod slides to and fro towards the right and
left of the machine; the left-hand end of this rod is formed with a straight
rack which gears into a pinion so as to impart to the pinion an alternate
movement upon its axis; the spindle of this pinion carries a hook, which as

page_text: the upper needle rises and forms a loop passes through the loop and holds it
until the needle again descends, so that a single chain stitch is produced.
If a double chain stitch is required I substitute for this hook a needle
working horizontally, and with an eye near the point supplied with thread, and
this thread is taken by the alternate movement of the pinion through each
loop formed by the thread of the upper needle. Near the left-hand end of
the horizontal shaft I fit a third cam which bears against the under side of
a feed lever centred on the under side of the bed plate; as the shaft revolves
this cam raises the feed foot at the proper time above the work plate. The
cam also bears against one end of a block fitted loosely between the feed
lever and an adjusting screw, upon which it oscillates as on a pivot, so that
immediately after the feed lever is raised by the cam the cam forces forward
one end of the block, and the other end pushes back the feed lever, and thereby
causes the feed foot to perform the feed; springs return the feed lever and
the block to their first positions.
A modification of the combination or arrangement before described consists
in substituting for the rack and pinion for working the under needle or
hook the following mechanism :-I fit upon the horizontal shaft, instead of
the second grooved cam as before described, a cam which as the shaft revolves
bears against a projection on the under side of the bed plate or against any
other suitable fixed part, so that the shaft is caused to slide to and fro to the
left and right, and a hook or a needle supplied with thread on the left-hand
end of the shaft is thus carried through the loops as they are formed by the
thread of the upper needle. I prefer to fit the machine both with a hook and
an under needle carried respectively on the two ends of a cross piece on the
end of the horizontal shaft. This cross piece is adjustable by a screw or
otherwise so as to allow of either the hook or the needle being brought
into action according as a single or a double chain stitch is required.