AN ELECTRO-MAGNETIC MOTOR FOR SEWING AND OTHER MACHINES
Year: 1870

page_text: LETTERS PATENT to George Stevens and Joshua Hendy, of San
Francisco, California, in the United States of America, for the
Invention of "AN ELECTRO-MAGNETIC MOTOR FOR SEWING AND OTHER
MACHINES."
Sealed the 15th July 1870, and dated the 27th May 1870.
COMPLETE SPECIFICATION filed by the said George Stevens and
Joshua Hendy at the Office of the Commissioners of Patents, with
their Petition and Declaration, on the 27th May 1870, pursuant to
the 9th Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, GEORGE
STEVENS and JOSHUA HENDY, of San Francisco, California, in the United
States of America, send greeting.
"AN ELECTRC=
WHEREAS we are in possession of an Invention for
MAGNETIC MOTOR FOR SEWING AND OTHER MACHINES," and have made solemn
Declaration that we verily believe ourselves to be the true and first
Inventors thereof.

page_text: NOW KNOW YE, that we, the said George Stevens and Joshua Hendy,
do hereby declare that the following Complete Specification, under our
hands and seals, fully describes and ascertains the nature of our said
Invention, and in what manner the same is to be performed:-
Our Invention relates to an improved method of driving sewing and 5
other machines, and more especially refers to the use of electro-magnetism
as a motor.
It consists in a novel arrangement of the apparatus which forms the
motor, by which we are enabled with the same battery to obtain greatly
increased results from the coils.
It further consists in so constructing the armatures that they drive
the needle bar directly and without the intervention of other me-
chanism.
Our Invention also relates to a device or switch which is so connected
with the battery that any desired change of power can be very readily
effected. The feed movement is also very simply arranged and is driven
directly from the armatures.
Referring to the accompanying Drawings for a more complete
explanation of our Invention,-
Figure 1 (Sheet I.) is a side view of the essential portions of the
apparatus (except the battery) detached from the usual cabinet.
Figure 2 (Sheet II.) is a vertical transverse section of one pair of
coils, and shows the feed motion.
Figure 3 (Sheet II.) is a plan with the upper plate removed.
Figure 4 (Sheet III.) is a view of the switch, showing clearly the
method of connecting it with the battery to give variation in the
power.
A is a case which rests upon the top of a cabinet and serves to conceal
portions of the machinery, it also serves as a table for the work; two
pairs of coils B and C are placed so that their upper ends stand just
within or at the bottom of the case A to which they are secured; these
coils are placed at such a distance apart as to admit of the working of
an oscillating beam D, which is supported on standards over their central
line; this beam is balanced so that the magnets or armatures of one
pair of coils are connected to one end, and those of the other pair to
the opposite end.

page_text: The coils are constructed as shown in Fig. 2, being formed of insulated
wire coiled to a suitable size, leaving an opening through the centre
sufficiently large to admit the magnets and their armatures. The coil
is surrounded by an iron cylinder which greatly increases the power of
any given coil. Outside this cylinder another coil may be placed, and
this in turn enclosed by another iron cylinder; this gives good results,
but not so great in proportion as are obtained from a single coil and
cylinder, which we consider sufficient. The magnets b and c are made
as usual of soft iron, and each pair of bars are united by a plate d across
the top, or they may be formed in one piece as an U magnet reversed.
The magnets extend down into the coils about two-thirds of the depth
of the latter, and the armatures farise from the bottom about one-third
of the height of the coil, this construction also adding greatly to their
power. The oscillating beam D has one end connected to each of the
plates d, and from some convenient point on its length the needle bar E
arises and extends forward to the table of the sewing machine, over
which the work passes. From the center of the beam D an arm F
depends, and as the beam oscillates from the alternate attraction of the
magnets at either end this bar vibrates from side to side, striking
alternately pins on a vibrating bar i, which is pivoted at the bottom
and which is also caused to move from side to side. This alternately
forms and breaks contact with the two pole changers g and h, and causes
the pairs of coils B and C to act alternately. This moves the magrets
b, c, the beam D, and the needle bar E.
-A bar or
The feed motion is operated in the following manner:-
arm V extends forward from the end of the beam D and partakes of its
oscillations. Two standards m and n support a shaft G, which lies
parallel with and a short distance from the arm V. At one end of the
shaft is an arm H which projects over the arm V, and as this oscillates it
moves the arm H up and down, thus partially rotating the shaft G back
and forth at each oscillation. A small crank arm o is fixed to the
opposite end of the shaft G, and the upper end of this is so attached or
connected to the feed plate p as to move it forward and back, raising it
at the proper time.
In order to vary the power so as to have it completely under control
one pole of the battery is connected with the coils, as is clearly shown
in Fig. 4 at I. After leaving the coils the wire passes to the key J of
the switch. Three buttons r, s, t, are arranged upon an arc u over which

page_text: the extremity of the key moves.
The button r at one side is connected
with the second cup of the battery, and when the key rests on that
button only the first two cups will be in use. The button & is connected
with the third cup and the button t with the fourth cup, and by turning
the key to either of these an additional battery power will be brought
to bear on the coils. Any number of cups may be employed as a whole
battery, and the different buttons may be so connected as to include
any number of cups in either of the changes.
If found more desirable two or more pairs of coils could be connected
with each end of the oscillating beam D, but we have found that one
pair is sufficient for all ordinary purposes.
In order to prevent noise, and diminish the force with which the
magnets and armatures would meet, we pass the arms V through a case K,
within which are placed elastic cushions above and below, and against
which the bar strikes as it moves.
In the present case the mechanism is adapted to the sewing machine,
but it is obvious that with slight modifications it can easily be adapted
to other machines.
The battery may be placed at any convenient point, either at a distance
from the machine or within the cabinet, as is found most desirable.
Having thus described our Invention, what we desire to secure by
the grant of Letters Patent is,―
First. Operating the needle bar of a sewing machine directly from the
electro-magnets, either with or without the intervention of levers, or
so that the oscillations of the armatures between two or more electro-
magnets shall cause similar movements of the needle, substantially as
herein described.
Second. Constructing electro-magnets with one or more coils of wire
alternating with enclosing cylinders, substantially as described.
Third. Extending both magnets and armatures into the coils so that
each occupies a portion of the length of the coil, substantially as herein
specified.
Fourth. The peculiar construction and arrangement of the feeding
apparatus, substantially as herein described.
Fifth. The device herein described for changing and regulating the
power, whether applied to sewing or other machines, substantially as

page_text: Sixth. The elastic cushions within the case K to reduce the con-
cussion arising from the movement of the magnets, substantially as
described.
In witness whereof we have hereunto set our hands and seals,
this Thirteenth day of April One thousand eight hundred and
seventy.