Improvements in Electric Car Motors.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Car Motors.
I, JOHN CHRISTIANSEN of Quincy in the County of Norfolk and Common-
wealth of Massachusetts, United States of America, Mechanical Engineer, do
hereby declare the nature of my 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 the application of electric motors to
the propulsion of cars, especially where separate motor cars or electric locomotives
are employed, said motor cars or locomotives carrying no passengers; and the
objects of my improvements are, first, to place the electric motor inside of the car
where it is readily accessible and protected from grit and dust; second, to arrange
for a continuous rumming armature, the motion of which can at will be quickly
communicated to the axles of the car, and as quickly again released; third, to avoid
the employment of special and expensive motor-trucks for the attachment of the
electric motor as is now the general custom 1 attach my electric motor to any
ordinary horse-street-car without making any change in its running gear: fourth, to
reduce first cost and wear and tear, and the consequent expense of repairs to the
driving mechanism.
1 attain these objects by the mechanism illustrated in the accompanying drawing
in which
Fig. 1 represents an elevation of an electric motor car.
Fig. 2 is a plan view with roof removed, showing the floor plan of the car.
Fig. 3 is a section transversely through the car on the line p. q. showing the
running and driving gear.
Fig. 4 shows a modified construction.
Fig. 5 is a longitudinal elevation of two motors B² and B³ each having a grip
pulley (L. and M.) on the armature shaft as hereinafter explained.
A, is the body of a motor car resting on wheels V, V, and axles u, u, by means
of journal boxes W, W, and springs Z, Z, as indicated in Figure 3, and in a manner
now customary on street horse-railroads. D, D, are bevel gears, keyed on to the
car axles u, u, and C, C, are brackets mounted upon the car axles in such a manner
as to allow of a free revolving of the axle in the bracket, said brackets contain
cach a bevel pinion P and a pulley E, both keyed upon a shaft a, the pinion
meshing into the gear D on the car axle, and the pulleys being connected by an
endless belt I made of leather, rubber or other suitable material.
The brackets C, C, are supported in their position by a brace F, G, consisting of
two members and having two points of attachment, namely at the top and at the
bottom of one of the brackets, and only one point of attachment, namely at the top
of the other bracket, this arrangement holds the brackets always in the same
relative position to the car axle upon which they are mounted, and still allows of a
perfectly free movement of the axle and even admits of a lateral or horizontal
movement of the axle boxes in their guides, without in any way disturbing the
efficiency of the driving car. The top member of said brace also serves to take
the thrust caused by the tension of the belt I, which is provided with a tightener-
pulley Y, shown in Fig. 2.
Thus the driving mechanism is complete and is entirely independent of the car
body, or of the truck of the car, and not connected with either. It is evident that
if power be applied to the endless belt, the car axles and wheels must revolve, and
cause the car to move. The power to move the belt 1 is supplied by means of a
rotary grip, operated by the electric motor in the following manner: B is the
electric motor fastened upon the car floor, and free to follow the motions of the car

page_text: body. S is the armature shaft; upon this shaft place two pulleys, one grip
pulley M and one friction pulley N above and parallel to the armature shaft I
place another shaft T, said shaft having also a grip pulley L, and a friction
pulley K, which pulleys correspond in location to the pulleys on the armature
shaft. The shaft T is located in adjustable bearings, and by means of a screw or
other suitable device, the friction pulleys can be put in contact with each other
with any pressure that may be required to transmit the motion of the armature
shaft to the shaft T. The grip pulleys do not touch each other but are so adjusted
in size and position, as to leave a space between them somewhat larger than the
thickness of the endless belt 1, which passes between them. By means of a screw
thread and hand wheel O, or any other suitable device, I may cause these grip
pulleys to impinge upon on the belt, and if the notor is in motion the belt will be
caused to revolve, which will cause the car to move; a release of the grip pulleys
will at once release the belt and stop the car while still the armature may be kept
in motion if so desired.
The belt as will be noticed in Figures 1 and 2, has to make half a twist in order
to pass fatwise between the grip pulleys, a matter which the flexibility of the belt
and the considerable distance between the pulleys readily admits of.
The friction and grip pulleys are made of wood, leather or rubber, or other
suitable material having a large coefficient of friction. I may omit the two friction
pulleys if it is found that adhesion enough can be obtained on the belt without
them, introducing then simply an idler-pulley with the grip pulley M on the
armature shaft, said idler-pulley being operated in the same manner as described
for the grip pulley L, but by the arrangement as shown and described the power of
the grip is materially increased. I may also substitute gears for the two friction
pulleys if found desirable. I may also construct my rotary grips by employing two
motors in place of one, each motor having a grip pulley on the armature shaft; the
motors being placed in such a position as to have their grip pulleys act upon the
belt I, as heretofore described.
In place of bevel gears and bevel pinions I may use spur gears and pinions,
arranging the mechanism as in Fig. 4, also the bracc F, G, connecting the
brackets C, C, may be made adjustable by means of a screw and hand-wheel, or
other suitable device, enabling thus the taking up of the slack of the belt, I and
adjusting it to its proper tension. The rotary grip is in this case the same as
hereinbefore described.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is:
1. In an electric-motor car, the combination of an electric motor provided with
the armature-shaft S, having thereon the grip pulley M, with the shaft having
thereon the grip pulley L, and the endless belt 1, substantially as above
described.
2. In an electric motor-car, the combination of an electric motor, the endless
belt I, the grip-pulleys L and M, placed respectively on the shafts T and S, the
pulley E, the bevel-pinion P, the bevel-gear D and shaft U, substantially as above
described.
3. In an electric-motor-car the combination of a motor connected with the car-
body driving mechanism substantially as described, applied to each of the two car
axles and independent of trucks or car-body and connected by the endless belt I,
substantially as above described.
4. In an electric motor-car the combination of the axles U, the bevel-gear D,
the bevel-pinion P, the bracket C, and the braces F, G, substantially as above
described.
5. In an electric motor-car the combination of the bracket C, the pinion P,
the bevel-gear D, the pulley E, and the endless belt I, substantially as above
described.

page_text: 6. In an electric motor-car, the belt tightening device consisting of the
tightener-pulley Y, attached to a lever and capable of adjustment by means of
a screw in combination with the pulleys E, E, and the endless belt I, as above
described.
7. In an electric motor-car the combination of the armature shaft S, provided
with grip-pulley M, and friction pulley N, with the parallel and adjustable
shaft T, provided with the grip-pulley L, and with the friction pulley N, the
endless belt I, pulley T, pinion P, gear D, and shaft U, substantially as above
described.
8. In an electric motor-car the brace F, G, having two points of attachment
to one of the brackets C, and one point of attachment at the top of the other
bracket C, in combination with said brackets C, C, substantially as above
described.
9. In an electric motor-car the combination of the car axles and gears, and the
brackets C, containing pinions and pulleys mounted thereon, with the brace F, G,
attached at two points to one of the brackets and at one point to the other bracket,
as near the axle A. as possible, substantially as above described.
Dated this 12th day of May A.D. 1891.
HERBERT & Co.,
18, Buckingham Street, Strand, London, W.C., Agents to Applicant.