IMPROVEMENTS IN SEWING MACHINES
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Henry Percy at the Office of
the Commissioners of Patents, with his Petition, on the 20th February
1865.
I, HENRY PERCY, of Bawtry, in the West Riding of the County of York,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
SEWING MACHINES," to be as follows:-
From one side of a table which is supported upon legs of a convenient form
a fixed straight arm projects horizontally, which for the sake of distinction I
will call the "work arm," as it supports the material to be sewn.
Inside this
arm the shuttle carrying the under thread works to and fro in a groove, being
actuated as hereafter described. Rising from the table and overhanging the
work arm is a second fixed arm, which I will call "the needle arm." This
arm, instead of being straight, is curved or arched so as to leave a convenient
space between the two arms for the bulk of the work to pass through-when
required. The outer end of the needle arm is brought down to a convenient
distance from the work arm immediately over that part of the latter which
contains the shuttle. At the front of this needle arm is a curved lever of
about the same form and length as the said arm, the fulcrum of the said lever
being above the table (before spoken of) and about level with the top of the
work arm; the outer end of this lever carries fixed in it a slightly curved
needle through the eye of which the upper thread passes. The outer end of
the lever works in a curved guide or groove attached to or forming part of
the needle arm so as to keep the needle lever steady as it vibrates up and
down and prevent any lateral motion or oscillation of the needle in either its

page_text: ascent or descent. The shorter end of the needle lever carries a pin or stud
by means of which it receives its motion, as hereafter described. The table
(before named) supports in suitable bearings the driving or cam shaft mounted
transversely, and this shaft carries all the cams, cranks, or other devices which
drive the working parts of the machine, being itself driven by means of an
endless gut or band passing round a small pulley fixed thereon and round the
fly wheel, which is actuated by a treadle, or in any other convenient manner.
The front end of the cam shaft carries a face wheel in the inner side of which
is a groove in which the pin or stud on the shorter arm of the needle lever
works. The form of this groove is such as to cause the needle to descend
and pierce the work, carrying the upper thread with it, then to rise a short
distance so as to slacken the said thread and form a loop at the side of the
needle, next to make a slight dwell whilst the shuttle passes through the loop,
and, lastly, to rise up out of the fabric and draw the thread tight. The
shuttle is driven to and fro at the right moment in its groove in the work arm
by means of a longitudinal sliding bar or shuttle driver from which two fingers
project, one in front and one in rear of the shuttle. This sliding bar lies
inside the work arm and carries at its rear end a T-shaped head in which is
an irregularly formed slot in which a crank pin in connection with the cam
shaft works. The form of this slot is such that the action of the crank pin
upon the sliding bar causes the shuttle to dwell whilst the needle pierces the
fabric and rises to form the loop, then to pass through the loop, carrying the
under thread with it, to dwell again whilst the needle rises out of the fabric,
and then to return to its original position.
The feeding of the work or material to the needle so as to regulate the
length of stitch is effected as follows:-The work is pressed down on to the
feeder 'by means of a spring presser of the ordinary construction attached to
the end of the needle arm. The feeder (of which the upper surface is cor-
rugated or roughened) slidės in a transverse slot in the work arm and is
attached to one end of a long lever which passes inside the work arm,
having its fulcrum about the centre of the length thereof. The other end of
this last-named lever carries a pin which works against a face cam keyed on
the cam shaft. The form of this cam is such as to cause the feeder to advance
the work slightly after each stitch, and upon the upper surface of the shuttle
driver is a small rise or projection which raises the feeder up as it passes and
causes it to nip the fabric between its upper surface and the under surface of
the spring presser. By connecting the feeder to its lever by means of a small
bell crank it may be caused to feed longitudinally instead of transversely when
required, for instance, in sewing the seam of a coat sleeve. The pin which

page_text: works against the face of the cam is made adjustable by means of a screw so
as to regulate the length of the stitch with the greatest nicety. It is held
against the cam by means of a spring acting on the other end of the lever.
The tension device, which I employ for preventing the needle thread from
becoming slack, is formed of two plates pressed together by a light spring, the
interior surfaces of the said plates being waved or corrugated, and one of
them being furnished with pins or guides to direct the thread between their
surfaces. The presser may be varied in form so as to serve as a guide to
the fabric whilst being sewn; for instance, when used for quilting, where a
number of rows of stitching are required parallel to each other and equal
distances apart, a guide may be attached to the presser having an adjustable
centre hole, through which the needle may pass, with tubular arms extending on
each side transversely to the direction in which the fabric passes; within these
arms works a screw, one end of which has a right-handed thread and the other
end a left-handed thread cut thereon. On this screw are threaded two hanging
guides (one on each side of the presser), so that upon turning the screw in one
direction the guides will be caused to approach each other, and upon turning
it in the opposite direction they will be caused to recede from each other, so
as to set the guide to the gauge required. By thus having two guides, one
on each side of the central needle hole, the machine can quilt backwards and
forwards without the necessity for always beginning from the same end or
edge of the fabric to be quilted.
When this machine is used for sewing flat work a platform or table having
a slot or opening fitting outside the work arm may be attached thereto; and
I would here remark that although I have here described this machine as a
whole, any one (or more) of the above devices is equally applicable to other
sewing machines requiring or admitting of the same or similar movements.