IMPROVE- MENTS IN FEED MECHANISM FOR SEWING MACHINES
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by James Lusty at the Office of the
Commissioners of Patents, with his Petition, on the 13th January
1870.
I, JAMES LUSTY, of Ipswich, in the County of Suffolk, Turner and
Fitter, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN FEED MECHANISM FOR SEWING MACHINES," to be as follows:-
My Invention relates to a silent feed mechanism which is chiefly
designed to be applied to the machine commonly known as the "Wheeler
and Wilson" sewing machine, but it may be adapted to other machines
which have as a portion of their organization the device known as the
rotating hook, or which have their feed mechanism operated in a manner
similar to that of a rotating hook machine.
The ordinary feed mechanism hitherto employed in the aforesaid
"Wheeler and Wilson" machine consist of a bar which has a roughened
surface projecting up through the cloth plate, and which is moved to and
fro by means of a cam under the said cloth plate, which cam is so
formed as to give to the said bar not only its reciprocating endwise
motion, but also the required upward and downward movement which is
essential to the proper working of the machine. This cam is formed

page_text: and arranged to carry the feed bar in one direction to the full extent of
its stroke, the said bar being moved in the opposite direction by a spring.
The length of the stroke of the feed bar and consequently the degree of
fineness of the stitching is determined or regulated by means of an
eccentric which is fitted to turn upon a stud or pin attached to the cloth 5
plate at the end of the feed bar, and which by being adjusted on its
centre will stop the feed bar at any part of its forward stroke. It is
obvious that in this arrangement of parts the end of the lever will strike
the regulating eccentric at cach forward movement, and for this reason
the feed mechanism is one of the noisiests parts of the machine. I have 1
designed my improved feed mechanism with a view to prevent this noise,
and I thereby render the working of machines of this class greatly more
agreeable than heretofore.
in
As the said improved feed mechanism is more especially designed to be
applied to the aforesaid "Wheeler and Wilson" machine, I will confine
myself in this description to the said Invention as applied to such a
machine. On the shaft of the rotating hook of the said machine, but at
the end of the cloth plate opposite to that under which the rotating hook
works I fix a cam which acts on the end of the feed bar and gives to the
same the required to-and-fro motion. I do not change the feed bar. itself
any way except that I prevent its coming in contact with or being acted
on by the ordinary feed cam, which need not, however, be removed from
the machine. I do not change the lifting cam or its action on the feed
"bar as I find it most convenient to leave this part of the feed machine
as heretofore. I remove the regulating or adjusting eccentric from the
cloth plate, as that is no longer required with my improved. feed
"mechanism. The new cam which I place on the hook shaft to act on
the end of the feed bar not only moves the said bar at the proper times
'to impart thereto the desired reciprocating endwise motion, but remains
*in contact therewith throughout the entire movement of the said bar,
so that there is no concussion or striking of the said cam by the bar, and
therefore the feed is rendered practically silent. To produce this
continuous and noiseless action I incline the cam laterally upon the
shaft in such a manner that as it.rotates its side which is in contact with
the end of the bar approaches and receèdes therefrom and remains in
contact therewith throughout its entire revolution, in such a manner äs
to move the said bar and allow it to return at the proper times in relation
to the needle and the other parts of the sewing mechanism. The

page_text: regulation of the feed or the length of the stitches is effected by varying
the inclination of this cam. For this purpose I attach the said cam to
its socket or boss (which is fixed on the shaft) by means of a pivot or
joint. On the back or outer side of the cam extending from the said
joint is a short arm, under which I place a spring. This spring tends
continually to incline the cam upon its shaft in one direction, which
tendency is opposed by a small adjustable excenctric fitted on a stud or
arm projecting from the boss of the cam. This excentric has a handle
or lever whereby it may be turned on its pivot, and by this means the
cam is inclined more or less on the shaft and caused to impart a longer
or shorter stroke to the feed bar.
My improved feed mechanism may be readily applied to any existing
machine of this class above described by simply removing the old
regulating excentric and placing my improved mechanism or attach-
ment on the shaft, and this adjustment or change can be performed
without difficulty by any person of ordinary intelligence and skill
acquainted with the construction and working of a sewing machine.