Year: 1887

page_text: Date of Application, 11th Aug., 1887
Complete Left, 10th May, 1883
Complete Accepted, 15th June, 1888
YOMICIOS.
I, MICHAEL HOLROYD SMITH, of Crossley Street, Halifax, in the County of York,
Consulting Engineer, do hereby declare the nature of this invention to be as
follows
This invention relates to the employment of electro motors for the propulsion of
tram or railway cars, the object being to facilitate the application and efficiency
thereof, and it consists in details of construction and devices whereby the inventions
for which Letters Patent Nos. 17018, 56648, 622086 were granted to me, may be
advantageously combined.
According to my present invention I employ electrical motors for driving the tram
or other cars which have dual armatures, that is to say, two separate armatures, the
axis of which are in line with each other but which are capable of independent action
so that each armature can drive an axle or wheel of the car independently of the
others. Such motors may either be used singly or in groups; thus, where sharp
curves with steep grades or heavy loads have to be dealt with, I preferably employ
two such motors, each with a dual armature, each armature spindle being by suitable
gearing (preferably similar to what I have previously used or described in my former
Patents) in connection with a car wheel. Or a single motor may be used having two
polar fields such as shewn at Fig. 12 of the drawing to Patent No. 5664 80, each
polar field being provided with two armatures driving separate wheels as above
described. The wheels are thus free to revolve independently of each other. In this
arrangement no counter friction occurs when the car or coach is running upon
curves, and the irregular wearing, or want of equality in the diameter of the wheels
is immaterial, each one doing unhindered its full duty.
The centre of the car being free in the first described arrangement, I place there
one switch controlling the two compound motors, the switch used being substantially
either of the disc or of the barrel type illustrated and described in the Specification
to Patent No. 6220, the windings of the field magnets and armatures being suh-
stituted for the wire resistances shewn on the diagrammatic figures on sheet 1 of the

page_text: drawings to that Specification, so that the motors can be used either in series or in
parallel, and thus, instead of controlling the power by interposing a varying external
resistance, I control it by varying the internal resistances of the motors. The said
switch is operated by rods or levers extending to the driving platform, and bas in
combination therewith a rack and pinion, or studs and links so arranged that when the
disc or barrel is revolved, it operates the ring brush holder described in Patent
No. 1701% in such a manner that by turning the operating handle to the right, the
brushes are set for the motor to drive the car forwards; by turning to the left they
become set to drive the car backwards.
By the above described arrangement of utilising the wires constituting the field coils
and armature winding in place of external resistances the motors can be used in
series or in parallel or compound parallel, the dual armatures increasing the variety
of possible combinations.
The compound regulating-and reversing switch above described may also be used for
controlling one dual armature motor, when each armature drives a separate wheel,
or an axle with both wheels attached thereto for example as illustrated and described
in the Specification to Patent No. 566488.
1007

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for the Electrical Propulsion of Tram
Cars and other Vehicles.
I, MICHAEL HOLROYD SMITH of Crossley Street, Halifax, in the County of York,
Consulting Engineer, 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 :-—
This invention relates to the employment of electro motors for the propulsion
of tram or railway cars, the object being to facilitate the application and efficiency
thereof, and it consists in details of construction. and devices whereby the inventions
for which Letters Patent Nos. 1701 of 1885, 566488, 62208 were granted to me, may
be advantageously combined.
According to my present invention I employ electrical motors for driving the tram
or other cars, which have dual armatures, that is to say, two separate armatures,
the axes of which are in line with each other but which are capable of indepen-
dent action, so that each armature can drive an axle or wheel of the car independently
of the others. Such motors may. either be used singly or in groups; thus,
where sharp curves with steep grades or heavy loads have to be dealt with, Í
preferably employ two such motors, each with a dual armature, each armature
spindle being by suitable gearing (preferably similar to what I have previously
used or described in my former Patents) in connection with a car wheel. Or a single
motor may be used having two polar fields such as shewn at Fig. 12 of the drawing
to Patent No. 5664% each polar field being provided with two armatures driving
separate wheels as above described.
The wheels are thus free to revolve independently of each other. In this arrange-
ment no counter friction occurs when the car or coach is running upon curves, and
the irregular wearing, or want of equality in the diameter of the wheels is immaterial,
each one doing unhindered its full duty.
The centre of the car being free in the first described arrangement, I place there
one switch controlling the two compound motors, the switch used being substantially
either of the disc or of the barrel type illustrated and described in the Specification to
Patent No. 6220 the windings of the field magnets and armatures being substituted
for the wire resistances shewn on the diagrammatic figures on sheet 1 of the drawings
to that Specification, so that the motors can be used either in series or in parallel,
and thus, instead of controlling the power by interposing a varying external
resistance, I control it by varying the internal resistances of the motors. The said
switch is operated by rods or levers extending to the driving platform, and has
in combination therewith a rack and pinion or studs and links so arranged that when
the disc or barrel is revolved, it operates the ring brush holder described. in
Patent No. 1701% in such a manner that by turning the operating handle to the
right, the brushes are set for the motor to drive the car forwards, by turning to the
left they become set to drive the car backwards.

page_text: By the above described arrangement of utilising the wires constituting the field coils
and armature winding in place of external resistances, the motors can be used in series
or in parallel or compound parallel, the dual armatures increasing the variety of
possible combinations.
The compound regulating and reversing switch above described may also be used
for controlling one dual armature motor, when each armature drives a separate wheel,
or an axle with both wheels attached thereto for example as illustrated and described
in the Specification to Patent No. 56648*.
The accompanying drawings shew, by way of example, one arrangement of my
above described electro-motors with dual armatures as applied to a tramcar.
Fig. 1 shews a part longitudinal section, Fig. 2 shews a part sectional plan, Fig. 3
a cross section, and Figs. 4, 5, and 6 shew different modes of supporting the dual
armature spindles.
A A¹ are two electro-motors, arranged one on- each side of the car, centrally
between the two pairs of wheels, and having each within their magnetic fields a a¹
two independent armatures B' B², and B3 B4, the spindle of each armature being
geared by worm and worm wheel gearing at C, such for example as that described in
my Specification 5664, to one of the wheels of the car. For this purpose either both
wheels of each pair are arranged so that they can turn upon their axle, in which case the
worm wheels of the gear are fixed on the sleeves of the road wheels, or the one road
wheel is fixed to the axle, in which case its worm wheel is also fixed on the axle, the
other worm wheel being fixed on the sleeve of the loose road wheel. The axes of the
dual armatures are in line with each other, and their inner ends may be supported in
various ways so as to be capable of rotating independently of each other;
thus
as shewn at Fig. 4 there may be fixed in the middle of the magnetic field A a disc D
of non-magnetic metal, having two bushes d d in which the inner ends of the
armature axes 61 63 take a bearing; or the disc D may have projecting spindles dd,
as at Fig. 5, on which the hollow inner ends of the axes 61 62 run; or again, the
central support D may be dispensed with, and the one spindle & bo uiade hollow, the
hollow spindle being supported within it as at Fig. 6, so that each axis serves as a
support to the other.
This arrangement would offer the advantage that when both armatures are
running at the same speed, the inner ends of the armature spindles are subject to no
friction, while at other times they are only subject to the comparatively small amount
of friction due to their difference of speed.
From the above arrangement it will be seen that each road wheel will be driven
independently of the others by its armature.
As the reversal of the direction of rotation necessitates the reversal of the internal
coupling of the motors this may be effected by reversing the positions of the
commutator brushes by means of toothed pinions E Fig. 3 gearing with toothed racks
on rods F F that are moved in one direction or the other by suitable gearing from
the end of the car.
The motion of the two compound motors is controlled by means of a compound
switch G arranged between the motors and rotated by means of a rod H extending to
the drivers platform and operated by any suitable gear. This switch is constructed
and operates in the same manner as described in the Specification to my Patent
No. 6220 of 1886, the resistance coils there described being replaced by the field
magnet and armature coils, with which the switch is connected in the following
manner. 1 and two are the terminals of the switch, which are connected with the
source of electric energy; the contacts are so coupled that terminal 3 controls the
coils 11 of the field magnets of the motor A; the terminal 4 the coils of the
armature B', terminal 5 the coils of armature B2, terminal 6 the coils 12 of the field
magnets of A. In like manner the terminals 7 and 10 control respectively the coils 13
and 14 of the field magnets of A' and the terminals 8 and 9 the coils of the
armatures B and B of A'.
The said terininals being regarded identical with those illustrated diagrammatically
on sheet I of Patent No. 6220, (but an extension thereof) and the armature and

page_text: field windings as the resistances there marked a, it will be readily understood by those
skilled in the art that numerous variations of the power will be effected by the
rotation of the switch.
Thus, according as the switch G is brought into position for establishing one
or other of the above described connections, the internal resistance of the motors, and
consequently the power given out thereby will be modified in a corresponding
manner, enabling a variation of speed between wide limits to be obtained, as circum-
stances may require for starting, stopping, going at full or moderate speed, or
slowing.
It will be evident that the same arrangement may be adopted with only a single
compound motor, as also with a greater number of such motors than two.
In place of the cylindrical or barrel switch shewn may also be used the switch of
disc form described in the Specification to Patent No. 6220 the arrangement of the
connections being otherwise the same as described.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. Constructing electro motors with two independent armatures within one and the
same magnetic field, the axes of the armatures being in line with each other but
capable of independent motion, substantially as and for the purposes herein set
forth.
2. Arranging electro motors with independent dual armatures such as are referred
to in the preceding claim, in combination with the wheels or axles of a tram car
or other vehicle in such manner that each armature is made to impart independent
motion to one of the wheels or axles substantially as herein described.
3. Arranging two electro motors with independent dual armatures such as are
referred to in the preceding claims in combination with two pairs of road wheels, so
arranged that each armature is made to impart independent motion to one of the
wheels, substantially as herein described.
4. Combining a compound switch such as is described in the Specification to
Patent No. 62208 with the field magnet and armature coils of one or more electro-
motors in such manner that the coils of the field magnets and of the armatures may
thereby be connected either wholly in series or wholly in parallel, or partly in series,
and partly in parallel, whereby the internal resistance and consequently the power of
the motor can be varied, substantially as herein described.
5. The combination with an electro motor having independent dual armatures such
as are referred to in the preceding claims with a compound switch having a series of
contacts each of which is connected separately with one of the field magnet and
armature coils, the switch being so arranged that according as it is brought into one
position or the other it causes the current to flow through the several coils either in
series or in parallel, or partly in series or partly in parallel so as to thereby vary the
resistance and consequently the power of the motor.
6. The combination of a compound switch of the kind described in the Specification
o Patent No. 6220 with two electro-motors with independent dual armaturès
substantially as herein described with reference to the accompanying drawings.
ABEL & IMRAY,
Agents for the Applicant.