CERTAIN IMPROVEMENTS IN SEWING MACHINES
Year: 1876

page_text: LETTERS PATENT to William Dore, of Manchester, in the County of Lancaster,
Mechanic, John Pitt Tapley, of West Gorton, in the same County, Mechanic,
and Charles Wilson, of Patricroft, in the same County, Joiner, for the Inven-
tion of "CERTAIN IMPROVEMENTS IN SEWING MACHINES."
led the 7th November 1876, and dated the 10th August 1876.
PROVISIONAL SPECIFICATION left by the said William Dore, John Pitt
Tapley, and Charles Wilson at the Office of the Commissioners of Patents on
the 10th August 1876.
WILLIAM DORE, of Manchester, in the County of Lancaster, Mechanic, JOHN PITT
TAPLEY, of West Gorton, in the same County, Mechanic, and CHARLES WILSON, of
Patricroft, in the same County, Joiner. "CERTAIN IMPROVEMENTS IN SEWING
MACHINES."
Our Invention relates, first, to the mechanism for actuating the shuttle, and for
giving the feed; this mechanism consists of a disc, to which is fixed an eccentric,
which works the short arm of an elbow lever, the long arm of which is connected
to the shuttle carrier. To the same disc is connected another eccentric for actuating
the feed lever, which communicates motion to a tappet for raising and moving the
feed rack.
The second part of our Invention consists of an improved arrangement of
mechanism for governing the relative actions of the vertical needle and the shuttle.
The check lever passes, as usual, through the needle bar, and the position of the
check lever is governed by a flat spring placed outside the arm instead of inside, as
heretofore. The point of this spring takes into notches in a trigger to regulate the
height of the check lever; this mode of working the check lever enables us to time
the motion of the shuttle so that the threads shall interlock the moment the needle
bar and the shuttle have arrived at the extremity of their traverse.
The third part of our Invention relates to an improved mode of regulating the
tension of the thread from the shuttle. To the plate of the sewing machine inside
the shuttle race is hinged a finger, the end of which bears on the spring of the
shuttle. When the shuttle is at the end of its traverse the thread from the shuttle
passes, as usual, under the spring, and the pressure of the finger on the spring is
varied according to the tension required by a screw acting on a lever, to which the

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Dore, John Pitt Tapley, and Charles Wilson in the Great
Seal Patent Office on the 1st February 1877.
WILLIAM DORE, of Manchester, in the County of Lancaster, Mechanic, JOHN PITT
TAPLEY, of West Gorton, in the samo County, Mechanic, and CHARLES WILSON, of
Patricroft, in the same County, Joiner. "CERTAIN IMPROVEMENTS IN SEWING
MACHINES."
Our Invention relates,-
First. To certain improvements in the mechanism for actuating the shuttle, and
for giving the feed.
And, Secondly. To an improved mode of regulating the tension of the thread
from the shuttle.
And in order that our Invention may be fully understood we will proceed to
describe the accompanying Sheet of Drawings.
Fig. 1 is an end view, Fig. 2 a longitudinal section, and Fig. 3 a plan taken from
below of part of an ordinary sewing machine, to which the first part of our improve-
ments is applied.
a is the foundation plate of the machine; b; the driving shaft; and c, the eccentric
shaft, which is driven by a pair of bevel pinions, as usual, but we place the driving
pinion close to the bearing of the driving shaft, instead of on the other side of
the driven pinion, as now customary; c¹ is the ordinary balance disc or plate; and
d is the shuttle race, in which the shuttle carrier e traverses to and fro. To the
inside of the balance disc c¹ is fixed the eccentric c, on which fits the end of the
link f¹, the other end of which is jointed to the short arm of the elbow lever f,
which vibrates on the fulcrum stud f; the long arm of the elbow lover f is con-
nected to the shuttle carrier e, which slides in a slot in the side of the shuttle race,
as now customary. To the outside of the balance disc c¹ is fixed the eccentric c³,
on which the end of the link g¹ fits, and the other end of this link g¹ is jointed to
the short arm of the elbow lever g, which is also mounted on the stud f2; the long
arm of the elbow lever g acts upon the tappet h for raising and moving the feed
racki, which moves in a slot parallel to the shuttle race, as usual.
The mode of operation is as follows:-As the disc c¹ revolves the eccentric c³
traverses the shuttle to the other end of the shuttle race; the eccentric c³ then
moves the long arm of the elbow lever g in the direction of the arrow in Fig. 3;
this action causes the tappet h to swivel on its fulcrum; the heel of the tappet then
lifts the feed rack i, and the tail of the tappet acting on the elbow ¹ moves the
feed rack forward to advance the cloth for the next stitch. When the lever g moves
back in the contrary direction to the arrow the spring & draws the feed rack í and
the tappet h back to their original positions.
By means of this improved mechanism the shuttle is passed through the loop
before the needle bar begins to ascend, thereby allowing more tension to be given
to the top cotton without breaking it, and without puckering the lightest fabric. The
machine can also be worked faster than is now possible in any other shuttle machine,
and a greater variety of thicknesses of fabric can be stitched without altering tho
tension.
Figs. 4 to 9 represent various views of our improved shuttle; Fig. 4 is a plan of
the shuttle without the spring. In one side of the shuttle is the recess m, into
which fits the projection n, soldered to the tension spring shewn detached in Fig. 5;
this spring is not fixed to the body of the shuttle, as now customary, but it is con-
nected to it by the hook at the small end as usual, and by the stud of the cam or
finger o, which will be explained hereafter.

page_text: Fig. 6 is a plan of the shuttle complete; Fig. 7 is a longitudinal, and Fig. 8 a
transverse section; Fig. 9 is a side elevation, shewing the ordinary reel or bobbin
and the slide bar p, one end of which is fixed to the nose of the shuttle. The cam o
fits inside the shuttle, and it can be turned partly round when required by a screw-
driver taking into the nick in the head of the stud to which it is fixed. The outer
circumference of the cain reaches to the curved back of the shuttle.
The thread
from the reel is taken around the slide bar p, then into the slot left between the
side of the shuttle and the end of the projection n on the tension spring, and thence
it passes between the spring and the side of the shuttle to the fabric.
In order to increase the tension on the thread the cam o must be turned partly
round in the manner described so as to bind the end of the cam against the curved
back of the shuttle, and this can be done by passing the end of the screw-driver
through a hole in the lid over the shuttle race without removing the shuttle from
the machine, and consequently without breaking the thread.
By this improvement in shuttles the tension boles usually employed are dis-
pensed with.
Having thus stated the nature of our Invention, and described the manner of
performing the same, we declare that we claim,-
First. The eccentrics c² and c³, and the parts acting in combination therewith for
moving the shuttle to and fro, and for working the feed motion.
And, Secondly. The improvements in shuttles for sewing machines, whereby the
tension on the thread can be varied without removing the shuttle from the machine,
and without breaking the thread.
In witness whereof, wo, the said William Dore, John Pitt Tapley, and Charles
Wilson, have hereto set our hands and seals, this Twenty-seventh day of
January One thousand eight hundred and seventy-seven.