Improvements in Electric Motors
Year: 1895

page_text: Date of Application, 4th Mar., 1895-Accepted, 11th May, 1895
Improvements in Electric Motors, -
I, ARCHIBALD H. BRINTNELL, of 10 Catharine Street, in the City of Toronto,
in the County of York, in the Province of Ontario, Canada, Electrician, do hereby
declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
My invention relates to improvements in electric motors and the object of the
invention is to devise a simple slow speed motor incapable of being burned out and
which may be reversed at full-speed and with a full potential of current without
damage to the motor and which also may be instantaneously stopped at any desired
point without the necessity of using any brake and it consists essentially of a
serial of double field magnets held in a circular non-magnetic frame supported on
suitable standards and having the inner ends of the poles of the magnets flush
with the inner circle of the frame and a number of spool armatures journalled free
to rotate in bearings in supporting discs secured to the main shaft of the motor
and in direct successive contact with the poles of the magnets, a commutator of
peculiar construction being provided to throw the current into both magnets and
spool armatures, so as to cause a pull upon the spool armatures in succession and
rotate the shaft as hereinafter more particularly explained.
Fig. 1, is a side elevation showing the upper half of one side of the commutator
and face rings broken away.
Fig. 2, is a vertical section through the motor on a line with the shaft.
In the drawings like letters of reference indicate corresponding parts in each
figure.
A, A, are the vertical standards in which is journalled the main shaft, B. C, are
a series of double inagnets supported in a circular open frame, D, of non-magnetic
metal. The horse-shoe magnet core, c, of each magnet, C, is laminated as shown
and straddles the outer rim, D¹, while the inner ends of the magnet extend into
notches, d, in the rim, D2, and are concentrically flush with the interior surface of
such inner rim. C, are the coils of the magnet, C, which are supported in the
openings, D, in the circular frame, D.
E, E, are two rings substantially Z-shaped in cross section, which extend around
the magnets and are secured to the ring, D, close to the horse shoe cores of same
on each side by screws, e. The rings are secured at the outer surface by screws, e',
to the standards, A. By this means the frame, D, is maintained in position.
F, F, are supplemental rings secured within the inner edge of the ring, E, and,
G. G, are rings of insulating material suitably secured to the rings, F.
H, H, are two discs preferably of non-magnetic metal secured to or forming
part of the hub, H', which is keyed to the shaft. 1, are a series of spool armatures
having coils, 11, and spindles, i, which are journalled near the outer periphery of
the discs H, H, and extend through the same. The spindles, i, are made of
non-magnetic metal. The ends of the spool armatures are preferably recessed as
shown.
The spool armatures and magnets are arranged in diametric pairs. The com-
mutator is comprised of two rings, J, J, of insulating material each situated to the
outside of the discs, H, H, and a plurality of brushes, J', J', corresponding in
number to the magnets and a plurality of brushes, J, corresponding in number to
the armatures and situated directly opposite to them.

page_text: The brushes, J', extend from the insulating ring, F, to the ring, J, and are bent
at their onter ends so as to form spring ends. The brushes, J, at one side press
upon the ends of the spindles, i, and at the outer side press upon insulated pins, ²²,
in the opposite ends of the spindles, i. The insulating rings, J, of the commutator
are provided with a number of. dead metallic sections, j, extending between the
spring contact brushes, J, which dead sections are designed to prevent sparking as
commutator revolves within the brushes, J¹, and to give a smoother running
surface.
K, K, is a double, arm secured to the rings, F, F, and connected by a cross
rod, K. By means of this double arm, K, the position of the brushes, J', is changed
either to increase or decrease the speed of the motor, stop it, or to reverse the
direction of rotation as hereinafter described.
The wiring is as follows. We will suppose that, L, is the positive wire and,
M, the negative. The current comes in to each diametric pair of coils (see Fig. 2)
successively, it being necessary that two of the brushes, J, are over two of the
brushes, J, each brush being diametrically opposite the other. The first brush, J',
to the left hand side of the standard A, is shown partially over the first brush, J².
The brush diametrically opposite is also in the same position. The second
brush, J', to the left is also shown partially over its corresponding brush, J, and
its diametric brush will also be in the same position circumferentially. In fact
two pairs of diametric brushes will always be in circuit, so that their corresponding
magnets will be exerting a pull upon their armatures. The current would con-
sequently pass in each case from the positive wire, L, in upon the wire, 1, through
one of the coils, C, of the magnets, C, the wire, 1, brushes, J, and, J', through
the spindle, and coil, I', of the spool armature, I, thus maguetizing such spool
armature out through the wire, m², pin, i', opposite brushes, J, and, J', wire, m',
through the other coils, o', and out by the wire, m, to the negative wire, M.
It will consequently be seen that the pull upon the diametric spool armatures, I,
will be such as to cause the discs, H, to rotate in the direction indicated by arrow.
Each successive diametric pairs of brushes, J', pass ou to the brushes, J³, serving
to continue the rotation of the discs in the same direction and the result of the
pull of the magnets upon the spool armature being to rotate them in their bearings
in the opposite direction.
The nearer the brushes, J, are placed circumferentially to the magnet core the
less will be the speed, and the farther away the greater except that there is a
maximum distance in which they must be placed and that is indicated as closely as
possible in the drawings.
To reverse the direction of rotation of the motor it will necessarily be seen that
the brushes, J', attached to, the ring, G, may be moved by the double arm, K, so
as to place them in the same relative position circumferentially on the opposite side
of the cores.
It will be noticed in the construction of iny machine that there is no air space
between the armatures and poles of the magnet but that they rotate directly thercon
and consequently I am enabled by the construction shown to always maintain a
very strong pull between the spool armatures and magnets.
As BOOD as the
armature comes opposite the magnet of course the current is thrown out and both
magnet and armature are demagnetized.
By bringing around the brushes, J', opposite to the magnets the machine may
be stopped practically instantaneously and held from rotation by the magnetism
being retained in the field coils and armatures as the current is still on. This it
will be readily seen is very important when my motor is employed to run elevators,
or for other purposes in which it is necessary to stop the machine instantaneously
and hold it in any desired position. No brake, therefore, would be required as the
impetus is checked immediately.
From the construction adopted it will also be seen that the direction of rotation
may be reversed at full speed with a full potential of current without burning out
or otherwise damaging the motor.

page_text: Having now described and ascertained the nature of my said invention, and in
what manner the same is to be performed, I declare that what I claim is :-
1. An electric motor comprising a plurality of magnets circularly arranged in a
suitable frame, so that the poles touch and are circumferentially flush with a
common circle and a number of spool armatures journalled in bearings in disos
secured to the main shaft and caused to rotate in their bearings by the pull exerted
by the poles of the magnets with which they come in direct and rolling contact as
and for the purpose specified..
2. The combination with a plurality of horse shoe magnets supported in a
circular frame of non-magnetic metal and with their poles extending through notches
made in the sides of the inner rim of the frame, so that the ends of the poles are
circumferentially flush with the inner rim, of a series of spool armatures journalled
in discs secured to the main shaft and means whereby a current is thrown into
one or more diametric pairs of magnets and armatures successively as and for the
purpose specified.
3. The combination with a circular non-magnetic frame, D, provided with a
plurality of laminated horse shoe magnets with coils and the rings, E, secured to
the outer ends of the magnets and supported in the frame, and the rims, F,
and, G, provided with spring contact brushes, J', of the spool armatures, I, provided
with spindles, i, which are journalled in the discs, H, H, secured to the shaft, B,
the insulating rings, J, J, the brushes, J', secured to the rings, J, and commutating
means whereby the current is carried simultaneously and successively through the
Co-acting magnets and armatures as and for the purpose specified.
4. The combination with a circular non-magnetic frame, D, provided with a
plurality of laminated horse shoe magnets with coils, and the rings, E, secured to
the outer ends of the magnets and supported in the frame, and the rims, F, and, G,
provided with spring contact brushes, J', of the spool armatures, I, provided with
spindles, i, which are journalled in the discs, H, H, secured to the shaft, B, the
insulating rings, J, J, the brushes, J, secured to the ring, J, and the main current
wires, L, and, M, connected by a wire, l, to one coil and the current being carried
by wires,, brush, J', brush, J', spindle, i, coil, 1', wire, m³, pin, 1, brushes, J,
and, J', wire, m', coil, C', wire, m, to negative wire, M, successively for each pair
of diametric co-acting magnets and armatures as and for the purpose specified.
Dated this 4th dex of March 1805
BOULT & WADE,
Agents for the Applicant.