A NEW OR IMPROVED ELECTRIC MOTOR, PARTS OF WHICH ARE APPLICABLE TO OTHER ELECTRO-MAGNETIC APPLIANCES
Year: 1878

page_text: LETTERS PATENT to Ernest John Harling, Telegraph Engineer, of City Road,
and Henry Bull, Mechanical Engineer, of Hackney Road, both in the County
of Middlesex, for the Invention of "A NEW OR IMPROVED ELECTRIC MOTOR,
PARTS OF WHICH ARE APPLICABLE TO OTHER ELECTRO-MAGNETIC APPLIANCES."
Sealed the 20th September 1878, and dated the 18th July 1878.
PROVISIONAL SPECIFICATION left by the said Ernest John Harling and
Henry Bull at the Office of the Commissioners of Patents on the 18th July
1878.
ERNEST JOHN HARLING, Telegraph Engineer, of City Road, and HENRY BULL,
Mechanical Engineer, of Hackney Road, both in the County of Middlesex. "A
NEW OR IMPROVED ELECTRIC MOTOR, PARTS OF WHICH ARE APPLICABLE TO OTHER
ELECTRIO-MAGNETIC APPLIANCES."
This Invention relates to the employment of electro-magnetic force as a motive
power, and to apparatus for applying that force in a practical manner for the purpose
of transmission to machinery of all kinds.
In carrying out experiments with the above objects in view, we found that the
attractive power of electro-magnetism will actuate the arm of a lever provided or
shod with or formed of iron or steel when such lever is brought within the range
of its influence. Thus if the free end of a pivoted lever be brought up to or
within the range of the rays of. magnetism of one or other of the pole pieces at the
end of an electro-magnetic coil, said free end of the lever will be forcibly attracted
to the pole piece, and that the attractive force is increased or diminished according
to the dimensions of the surfaces of the arm and pole piece exposed to the magnetic
influences and the strength of the magnetic current,

page_text: In seeking to apply this experience we found that if we mounted a radial arm
upon a shaft free to rotate, and in such relation to the pole piece of an electro-
magnetic coil as that the said radial arm would extend within the range of the
magnetic rays of said pole, and that if by partial rotation of the shaft the said radial
arm be brought just within such range and there left, the attractive power would
forcibly attract the arm and carry the shaft further around until the said arm came to
the centre of the influence of the rays where it would be held by the full attractive
force. If then at this juncture the current be made to "break" the attractive
influence will immediately cease.
Again, if by this partial revolution of the shaft another radial arm mounted on
the same shaft be brought within the attractive influence of the poles of another
magnetic coil, a further and continued rotation of the shaft would ensue, and so on
with other such arms and pole rays until a complete revolution or continuous
rotation of the shaft will be effected, and this rotation by suitable transmission it
seemed possible to apply as a motive power, and this our Invention consists in the
means of converting electro-magnetic force into a mechanical one, which means are
essentially a shaft which we denominate a "transmission shaft" with radial arms
mounted thereon in pairs, preferably that is one arm extending out on each side of
the shaft and opposite to each other, which pairs of radial arms we denominate
flyers," several of which flyers are mounted along the shaft so as to extend out at
right angles to the shaft but at different angles or position relatively to each other,
that is, not in the same longitudinal radial planes.
"
Below the shaft and immediately under the "flyers" are placed electro-magnetic
coils, and perpendicularly thereto and at each end of the "coils" are "pole pieces"
set sufficiently wide apart that the radial arms on rotation of the shaft will not
come in contact therewith. These pole pieces attract the flyers alternately until
they come opposite to the centre of their influence when the current of the coils is
to be "broken," that is, the power is removed from that particular flyer by means
of a "commutator," all as more fully herein-after described.
In constructing the apparatus the transmission shaft is mounted in bearings or
centres, upon said shaft is mounted by bolting or keying the clectro-magnetic
"flyers," said "flyers" being made of two bars of soft iron connected at their
extremities by two steel bars or pole pieces, which latter are rounded on their outer
faces to form arcs of a circle of which the transmission shaft is the centre.
25
In mounting these "flyers" on the transmission shaft holes are drilled centrally
through the two iron bars so that the "flyers" may be threaded on to the shaft and
form pairs of radial arms, but said arms of the flyer" are to be lined with a short
tube or boss of brass or other magneto-insulating substance to insulate the " flyer
from the shaft.
"
The "flyers" are arranged on the shaft so as to extend out radially therefrom in
different longitudinally radial planes.
Under the shaft and below each of the "flyers" we provide an electro-magnetic
coil which is fixed at right angles to the said shaft..
"
At the opposite end of the coil there is provided an upright piece of iron which
we call a pole" piece, so that there will be two pole pieces opposite to each
other, one at each end of the coil. On each of these pole pieces are fixed by bolts
or otherwise two iron quarter-circle segment plates, said plates, being sections of a.
circumferential band or circle whereof the transmission shaft is the centre.
On to the outer edge of each of these said segment plates is attached a pole plate,
there. being accordingly two of these pole plates to each two segment plates, which
latter are mounted side by side as before described, and thus will be formed what
we term "pole cups."
One of these said "pole cups" are arranged on each of the pole pieces situated,
preferably in horizontal planes relatively one above the other, and thus the trans-
mission shaft and the pairs of electro-magnetic flyers are spanned as it were by the
pole cups, and hence we denominate this arrangement of coil pole pieces and pole,
cups electro-magnetic spanner."
«

page_text: Those flyers that come within the influence of the magnetic rays of the cups.
will upon the current being passed become immediately bathed as it were in the
rays of magnetism that is thus set up in the said cups, whereby a powerful
attractive pull will be communicated to or upon the flyers and opposite sides of the
shaft to draw said flyers to the centre of the "pole cups."
Two or more of these "spanners" will be used, according to the number of "flyers"
mounted upon the shaft and power required to be imparted to the said transmission
shaft.
It should be remarked that the pole cups are made of the two segment plates,
either divided by insulating compound or insulating metal interposed between the
two inner and adjacent edges thereof, or set apart from each other in order that the
magnetic force communicated through the coil and pole pieces to the said pole cups
may be more equalized throughout the body of the "cup" and take effect upon a larger
surface of the "flyer" rotating within the "spanner" than otherwise would be the
case; accordingly we may use in forming the "spanners" two coils with pole piece
at each end of each coil, and then upon each pole piece mount one of the divided
pieces of the pole cups, that is, one segment plate and one outside cheek, so as to
form a wider pole cup which will accommodate a flyer of larger surface dimensions,
and according to the dimensions of the "spanners," power of current, and of the
diameter of the flyers, so will the power exerted upon the flyers and transmission
shaft be increased or diminished.
We have described the cups as being divided in order to have greater effect upon
the side surface of the flyers, and this arrangement we prefer to employ, but the
curved segment plate of the cups may be solid, and in this case the steel pole pieces
of the "flyers" must be divided transversely between the two bars of which they
are constructed.
On to one end of the transmission shaft is mounted a toothed wheel which gears
with a second toothed wheel of same dimensions mounted upon and actuating a
communicator of special construction, and which I call a "pole changer," for the
purpose of "
making” and “breaking" contact or the currents of the various
electro-magnetic spanners" at the moment when there shall have been exerted
the requisite "pull" of the magnetic attraction upon the "flyers" of the shaft.
"
The special commutator or "pole changer" consists of a small drum or cylinder
of non-conducting material mounted so as to be free to rotate, and is driven by
toothed gearing direct from the transmission shaft.
Upon the said drum are bands or parts of bands which are broken, that is, are
not continuous (for the purpose of "making" and "breaking" contact), and which
we call "pole changer bands."
On each side of this drum is provided a metal conducting plate, the one on one
side of the commutator drum being "positive" and the other "negative." To these
said plates are attached small bracket pieces, the arms of which extend over the
drum and carries on the outer end thereof a small strip of band spring whereon is
mounted a light brass roller covered with a silver band or other suitable metal for
making a contact, and therefore these are called "contact makers." The rollers of
these contact makers" by means of the springs and of an adjusting screw acting
thereon are caused to bear more or less lightly upon the pole changer bands.
<<
The positive pole of the battery will now be connected by wire with one of the
conducting plates of the commutator, and the negative pole with the other con-
ducting plate.
The positive and negative poles of the coil or coils of each "spanner" is now
connected by wire and binding screw with one set of the "contact maker brackets"
of the commutator, the positive pole being connected to the bracket secured to the
positive" conducting plate, and vice versa for the negative poles.
<<
The pole pieces of the "spanners" may be connected by a permanent horse-shoe
magnet, whereby we obtain rays of permanent magnetism within the pole cups in
addition to the rays of electro-magnetism.
The transmission shaft has mounted thereon a fly wheel, and the means of trans-

page_text: mission of the rotation of the transmission shaft are of any ordinary or well-known
kind.
The machine is started by passing the current from the battery by ordinary
"switch" which will be connected directly with the commutator to the cups of the
"spanner" or "spanners" that is or are in "contact," whereupon the drag of the
electro-magnetic attraction will take effect upon that flyer or flyers that is or
are within its or their influence, so causing the partial rotation of the transmission
shaft and with it by the gearing the commutator barrel and pole changer bands,
which last are "timed" to "break" the current when the full force of the particular
spanner" or "spanners" and "flyer" or "flyers" has been exerted, and to "make"
contact for the next "spanner" or "spanners" and "flyer" or "flyers."
ff
The engine will be driven in the reverse direction by reversing the current by the
battery switch.
"
The special commutator herein described is applicable and would be very useful
in telegraphic and other electro-magnetic instruments for “making ” and “breaking"
contact.