IMPROVEMENTS IN SEWING MACHINES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by John Magill at the Office of the
Commissioners of Patents on the 28th November 1878.
JOHN MAGILL, of the City of Manchester, in the County of Lancaster, Engineer.
"IMPROVEMENTS IN SEWING MACHINES."
Firstly. My Invention relates to mechanism for actuating the needle slide, and
consists in the use of an excentric or crank to work a connecting rod jointed to an
arm upon a shaft which is thus made to rock or oscillate, upon which shaft there is
another arm that is jointed to another rod that is connected to the needle slide.
The movement is so arranged that the last named arm causes the needle to
descend to its lowest position when the arm and connecting rod are in a straight
line from the axis of the rocking shaft, and by continuing the motion of the arm a
little past this position the slight ascent is made to form the "loop" in the needle
thread, then the arm makes its back movement, first causing the needle to descend
slightly, and then lift to its highest position.
This mode of actuating the needle slide is applicable for shuttle machines, and
for those operating by a curved needle under the cloth plate.
Secondly. My Invention relates to the shuttle, or to a part taking the place of
the ordinary shuttles in sewing machines, and my Invention consists in making
such shuttles in a complete cylindrical form with one end of the cylinder closed,
the other end open to insert in it the spool of thread with its axis in the axis of the
cylinder.
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This cylinder has a hook formed in its surface, to take hold of the loop of the
needle thread as hereinafter described.
This shuttle has not a reciprocating motion same as the ordinary shuttle, but it
has an oscillating movement given to it on its axis (which is placed vertical) by a
driver that enters a bevel slot in the closed end of the shuttle, this driver being
actuated by a pinion on its axis, which gears with a toothed rack actuated by a
cam, or by an excentric by preference. The shuttle is placed in a case under the
cloth plate, which case is or may be hinged to open so that it may be readily
inserted and removed from the case when required.

page_text: The thread is or may be drawn off the reel from the top or open end of the
shuttle or through a hole in the side of the shuttle, and a spring is or may be
applied to act on the thread to give tension, if desired.
A modification of the shuttle consists in forming the reels to act both as reels
and shuttles, namely, by forming one end of the reel with a hook to take the loop
of the needle thread and by making a slot in that end, so that the driver may act
upon it to give it the required oscillations.
Another modification consists in driving the shuttle continually in one direction,
that is, giving it rotary motion; the thread is or may be drawn from a cop in the
shuttle, or from the end of a reel in the shuttle.
Thirdly. My Invention relates to a combination and arrangement of the
mechanism above described, and consists in placing a shaft to rotate in suitable
bearings on the framing below the level of the cloth plate, this shaft being the
driving shaft, and upon it there is an excentric which by a connecting rod gives
oscillations to an upper shaft referred to under the first head of my Invention, the
needle slide being actuated by mechanism as described.
The rotary shaft has an excentric upon it that works a slide on the frame of the
machine to and fro, this slide having a rack upon it that gears with the pinion on
the shuttle driver, which gives movement to the shuttle mechanism arranged as
herein before described, so that when the needle descends the hook on the shuttle
takes the loop of the thread, and causes it to pass under and round or partly round
the shuttle.
A toothed sector or other suitable mechanism may be used in place of the slide.
When the shuttle is to be rotated a bevel wheel on the lower shaft is made to
gear with one on the axis of the shuttle driver.
Another modification consists in placing the shuttle case and driver so that its
axis is in a horizontal instead of the vertical position.
The feed is worked from the end of the rotary shaft; same as in the Wilcox and
Gibbs and other sewing machines.
My improved shuttle mechanism is applicable to machines for shoe making or
repairing, as it occupies but little space, and the spool will hold a large supply of
thread.
A machine combining my improvements can be worked at a great speed, and the
shuttle is less liable than shuttles in ordinary machines to "miss stitches."