IMPROVEMENTS IN SEWING MACHINES, APPLICABLE TO OTHER MACHINES WORKED. BY FOOT POWER
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the
Office of the Commissioners of Patents, with his Petition, on the
5th January 1869.-A communication from abroad by Greenleaf
Stackpole, of the City of New York, in the County and State of
New York, United States of America.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the Courty
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SEWING MACHINES, APPLICABLE TO OTHER
MACHINES WORKED. BY FOOT POWER," a communication from abroad by
Greenleaf Stackpole, of the City of New York, in the County and State
of New York, United States of America, to be as follows:-
This Invention relates to an improved mode of driving sewing and
knitting machines and all analogous machines, whereby the power
applied to the treadle in the ordinary manner is augmented, and the dead
centres resulting from the arc of a crank are obviated.
The object of this Invention is to reduce the labor of operating sewing
and knitting machines and other analogous machines to the lowest
practicable point, and at the same time to secure the greatest possible
rate of speed; which it is proposed to accomplish by means of levers
acting upon the periphery of a wheel in such a manner as to entirely

page_text: overcome the ordinary dead centres, and gain a momentum by throwing
the balance or fly wheel forward faster than the treadle motion.
In carrying out this Invention a grooved wheel is employed, mounted
loosely on the driving shaft, which by the upward motion of the treadle
is brough in contact with a friction ring by means of a lever acting
upon the same. A second and similar grooved wheel acts in the same
manner upon another friction ring upon the downward motion of the
treadles, the said friction rings acting alternately upon a third wheel,
which may be termed the driving wheel, situate between the two grooved
wheels above referred to, and secured to or made fast on the shaft by a
set screw, the parts being held together by means of adjustable collars
upon the shaft. When the treadle is moved the machine is set in
motion by means of a cord passing through an open frame on the top of
the connecting rod leading from the treadle, such cord passing to an
adjustable yoke, a thumb screw being used to tighten the cord as it
stretches or grows loose. The connecting rod is attached to the open
frame and to the treadle in the ordinary manner. The arrangement of
the friction rings and levers is the same on both sides of the driving
wheel. Two pins are fastened to the inner surfaces of the grooved
wheels, the one pin acting upon the lever on its forward motion, spread-
ing the friction ring and causing it to take hold of the inner surface of
the driving wheel, which is grooved on either side to admit the said
ring and lever, so that they are flush with its end surface. The friction
ring carries around with it the driving wheel, which is fast on the main
shaft, by the upward motion of the treadle propelling the machine
forward, when the second pin is brought in contact with the lever on
the downward motion of the treadle, relieving the friction and carrying
the ring back independently of the driving wheel, whilst the opposite
and corresponding ring clutches the driving wheel on the other side
continuing its forward motion. Thus the driving wheel is acted upon
alternately by the two friction rings and levers, producing a continuous
forward motion. A break is hinged to the table, and is held in position
by a spring, the machine being controlled by pressing the break against
the side of the fly wheel.