IMPROVEMENTS IN Sewing machines
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Harry Gamwell at the Office
of the Commissioners of Patents on the 3rd October 1883.
HARRY GAMWELL of Liverpool in the county of Lancaster
SEWING MACHINES
"
"IMPROVEMENTS IN
Sewing machines as ordinarily constructed will only work one way. This
frequently results in great inconvenience, and to remedy this defect the reversible
feed was tried, with little success however.
Now my invention consists in reversing the entire motion of the machine, and
running the stitch cam, needle bar cam, cotton cam, and other parts, so that each
shall follow each other in the same order, and at equal increments of time whichever
way the machine is run. A double pointed rotary shuttle or hook, taking the
cotton loop, can be employed and also arranged with gearing so as to take the
cotton loop at equal times, that is at equal angular distance of stroke whichever
way the machine is run, or a single pointed oscillating or reciprocating hook can
be used reciprocating as the loop is formed whichever way the machine be run. In
the case of power machines the change of motion can be effected by simple and
cross bands on a range of three pulleys or by other well known reversing
mechanism; in hand or foot machines the motion is simply reversed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Harry Gamwell in the Patent Office on the 3rd April 1884.
HARRY GAMWELL of Liverpool in the County of Lancaster
SEWING MACHINES
"
"IMPROVEMENTS IN
Sewing machines as ordinarily constructed will only work when turned in one
direction, and to remedy this defect and the inconvenience often arising therefrom
the reversible feed was invented but used however with but little success.
My invention relates to improvements in the design of and the arrangement of
the parts of a sewing machine whereby it will be enabled to sew when turned in
either direction.
It consists in taking the motion for the several parts of the machine direct from
the main or driving shaft and adjusting the stitch cam, needle-bar cam, cottons
control cam, and other parts so that each will follow the other in the same order
and at equal increments of time whether the machine be turned in one direction or
the other.
I employ a double pointed rotary shuttle, or a double pointed rotary hook, taking
the cotton loop while the machine is working in either direction, that is at equal
angular distance of stroke whichever way the machine is running, or I use a single
pointed hook oscillating or reciprocating. In the case of power machines the
change of motion can be effected by simple and cross bands on a range of three
pulleys or by other well known reversing mechanism; in hand or foot machines
the motion is simply reversed.
The invention is best described by the instance set forth in the accompanying
drawings being a sewing machine worked out on my principle, that is arranged so
thet every part is arranged or timed to perform its work at such consecutive
intervals that with a given speed the order of motion and the intervals between
the motions shall be exactly the same whether run backward or forward.
In these Fig. 1 is a side elevation.
Fig: 2 front elevation with cover removed.
Figs. 3 and 4 two views taken at right angles to each other of the feed regulating
lever.
Figs. 5 and 6 front view and section of shuttle mechanism.
Figs. 7 and 8 enlarged plan and section of shuttle.
It will be readily understood that I do not limit myself to the precise description
of machine shewn, as my invention can be easily applied or adapted to any other
description or class of machine.
A is the needle bar and B the presser foot bar both mounted so as to slide freely
in the bearings c c¹ of the headstock C. On the driving shaft D is mounted a
cam E for giving motion to the thread controller F. To this cam E is also attached-
the connecting rod G by means of which motion is imparted to the needle bar A.
Towards the other end of the driving shaft D is mounted a cam or éccentric H
which revolves in a square socket or bracket h formed on the top of the bar or
rod I. The bar or connecting rod I is carried by and slides in the socket J which
is pivoted to the bracket K and free to oscillate thereon. The bracket K is
adjustable in the slot k and retained therein by the thumb screw k¹. The other
end of the connecting rod I is attached to a horizontal rocking lever L either by
ball or other suitable bearings. The lever L is carried in ball bearings which
forms its fulcrum, whilst the shorter end is attached by any well known device
at to the feed bar M. The connecting rod I being carried in movable bearings J,
the amount of feed and consequently the length of stitch can be easily increased or
diminished by raising or lowering the bracket K which serves as a fulcrum to the

page_text: connecting rod I. The feed bar M is thus actuated by the cam H through the
connecting rod I and the rocking lever L receiving the four distinct motions
required therein by the action of the cam or eccentric H on its bearing in the rod L
N is the shuttle which is made to oscillate in the shuttle race O; this is formed as
follows; within the circular plate o is hinged at n a ring o¹ which prevents the
shuttle N leaving its position. The oscillating motion is conveyed to the shuttle
by means of a crank P on driving shaft D through connecting rod Q to crank R
on shaft S and then through the shuttle carrier or driver T attached to shaft S.
The shuttle is constructed as shewn at Figs 5 and 7. The spool cop or bobbin V
is carried on the pin o² and the required tension to the thread is obtained by
passing it between the plates o³, the under one of which is acted upon by a small
spiral spring. The thread after leaving the plates o³ is passed through a hole o* in
the hinged bar o from which it is passed forward to be acted upon by the needle.
The bar o closes over and keeps the bobbin in position. The points t. of the
shuttle carrier or driver T are slightly bevelled on the under side, and the bevelled
portion of the shuttle pass under them. The shuttle N is thereby held in position
its own weight as wear occurs always tending to keep it close to the face of
shuttle race.
Spring U acts upon the presser bar B and foot in the usual way. Other parts of
the machine not described may be of ordinary construction.
As hereinbefore described the construction and arrangement of the machine is
such that the different parts will receive a similar and some of them an identical
motion, and also that the motion in the several parts will follow each other at
equal intervals of time (the shaft being maintained at a given speed) irrespective
of the direction in which the machine is driven.
The operation is as follows:
'
Motion is transmitted to the driving shaft D through a hand wheel or pulley
attached to one end, and the several parts of the machine are actuated directly.
therefrom by means of the cam E, the cam or eccentric H, and the crank P.
1st. From the cam E the needle bar A receives a direct reciprocating motion
through the rod G attached to a pin pivoted to its face, and the thread controller
or tightener F receives motion from the slot e in the side of cam E in which a
roller fixed to it slides. The path or slot e of the cam is equal and similar at each
side of its point of furthest travel. Thus the relative motions of A and F are the
same should the shaft D be turned either to the left or to the right, and may be
so adjusted that F will rise when the needle bar A is about completing its up or
commencing its down stroke, though preferably when it is about three sixteenths
of an inch from having completed the stroke in an upward direction, so that the
finish of the stroke of the thread controller shall coincide in time with the dead
point in the needle bar's movement.
2nd. The cam or eccentric H acting on the connecting rod I imparts motion to
the feed bar M in the manner already described, and is so placed as to impart to
the rod I and through it to the feed bar M a similar motion whether the shaft D
be turned to or from the operator. The motion required in the feed bar M is four
fold, namely, 1st to rise nearly perpendicularly, 2nd to travel horizontally, 3rd. to
fall to a level to bring the teeth below the surface, and 4th. to travel back
horizontally at the lower level until the 1st position be again assumed. This
notion is the same and follows in the same order irrespective of the direction of
motion of the shaft D with this difference, that when the shaft D is turned towards
the operator the second or feed motion above named is from the operator, and
when the shaft D is turned from the operator the second or feed motion is towards
the operator.
3rd. The crank P imparts a reciprocating motion to the rod Q which attaches to
a crank R on the spindle S. The crank R has a longer throw than the crank P,
and in consequence the rotary motion of P is changed to a reciprocating motion
in R, and it will be seen that the position of the crank R (and consequently the
position of the shuttle carrier T at the other end of the spindle S) will be the same

page_text: when the crank P is at a given height either to the left or right of the shaft D!
The motion of the shuttle carrier T and of the shuttle N is therefore unchanged
with the direction of motion of shaft D.
The position of the several parts of the machine are shown in the drawing when
the needle bar is at the top of its upward stroke ready to descend, and it will be
seen on examination of these that the same movements will take place, be the
driving motion in one direction or the other. Thus the pin in the face of cam E is
perpendicularly over the centre, the roller in slot or path e of the same cam is at
its point of furthest travel, the cam or eccentric H has raised the rod I to its
highest position and holds it in the centre of its path of oscillation, and the crank P
is on its dead centre at the bottom of its stroke. The presser bar is raised and
lowered in the usual way by means of an eccentric lever W and held to its work
by the spring U which is held in place and whose tension is adjusted by thumb
screw n.
The action of the shuttle on the thread and the action of the thread during the
operation of sewing is not particularly described as it does not vary materially
from what is well known and understood, and for the shuttle itself and for the
shuttle race which are new a separate applications for Letters Patent has been
made.
Having now described my invention and the best mode known to me of carrying
it into effect, I wish it to be understood that what I desire to protect under Letters
Patent is:
1st. The manufacture of sewing machines having their movements arranged to
follow each other in a given order and at intervals coinciding with a given degree
of rotation of the driving shaft, whether the machine be running in a backward or
forward direction, by which means the operator is able to sew in one direction and
reverse his machine, sewing back on, or at close proximity, the previous track
of the machine, or at an acute angle to it without turning the material round,
substantially as described.
2nd. The arrangement of mechanism substantially as described for enabling a
machine to perform its work running in either direction.
In witness whereof I the said Harry Gamwell have hereunto set my hand and
seal this 31 day of March in the year of our Lord one thousand eight hundred
and eighty four.