IMPROVEMENTS RELATING TO THE PROPULSION OF TRAM GARS AND OTHER VEHICLES BY ELECTRICITY
Year: 1884

page_text: I ANTHONY RECKENZAUN of 8 Osborne Road Forest Gate, London, E. in' the
County of Essex, Engineer, do hereby declare the nature of my Invention for
IMPROVEMENTS RELATING TO THE PROPULSION OF TRAM GARS AND OTHER
VEHICLES BY ELECTRICITY to be as follows:-
This invention relates to the propulsion of tram cars, railway cars and the like,
by means of electro motors actuated by currents of electricity.
It is well known that the power required to start a car or to drive a car up an incline,
is very great, and therefore, powerful machines are necessary to provide for these
abnormal exertions. Electro-Motors are only efficient within certain narrow limits,
that is to say, a motor which has an efficiency of say 75 per cent when giving off five
horse power on the driving shaft, will probably give less than 60 per cent when working
up to 10 horse power.
On the other hand, a motor made to work with the greatest
economy at the rate of 10 horse power, will not be so economical when giving out
less power. I propose to overcome this difficulty to a great extent by employing
two, or if necessary, more than two motors, which when working together will give
the necessary power for starting the vehicle and for mounting inclines; and also to
ensure that when running on a level road the work of one only of such motors will
be sufficient. These several motors may be alike in size or they may be different,
but their number of revolutions are made to correspond according to the gearing
employed.
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By means of a switch, I can run the several motors "in parallel," or "in series,"
or singly, and thereby change the resistance of the circuit and with it the speeds of
the machines. In some cases I may use two or more distinct armatures on one
shaft, or I may employ two or more separate motors.
The gearing is so arranged that either one of the motors can drive the car in
either direction should one of the motors become disabled. If I employ two motors
I provide the shaft of each with a worm, which worm gears into a worm wheel
threaded upon the car axle. I prefer to place the two motors in a line, so that the
shaft of one motor drives the forward axle, and the shaft of the other the aft or
rear axle nearest to it, thus ensuring a firm grip upon the tails in starting and when
mounting inclines. The angle of the worm thread is such as to allow the free
movement of the axles when the current is switched off,
100

page_text: COMPLETE SPECIFICATION.
I ANTHONY RECKENZAUN of 8 Osborne Road, Forest Gate, London, E: in the
County of Essex, Engineer, do hereby declare the nature of my invention for
IMPROVEMENTS RELATING TO THE PROPULSION OF TRAM CARS AND OTHER
VEHICLES BY ELECTRICITY, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
It is well known that the power required to start a vehicle, or to drive it up an
incline, is very great; and, therefore, powerful machines are necessary to provide
for-these-abnormal exertions Electro-Motors are only efficient within certain
limits; that is to say, a motor which has a high efficiency-when-giving_off_5 horse
power on the driving shaft, will probably yield a smaller per centage of efficiency
when working up to 10 horse power; on the other hand, a motor constructed to
work with the greatest economy at the rate of 10 horse power, will not be so
economical when giving out less power.
C
Again, it is desirable that, in the propulsion―on land or water-of vehicles and
other objects demanding variable power, the Electro-motive force should be constant.
Now, with constant Electro-motive force and variable loads, variable currents and
speeds necessarily result. For instance, the 5 horse motor referred to above, if
supplied with a constant Electro-motive force will take a definite amount of current
at this normal power. Assuming that the load is doubled (as would be the case in
starting a car or when mounting a moderate gradient) the current flowing, will at
once be doubled, and the speed, reduced to about one half. This double current
will have the effect of heating the wire of the motor and probably of damaging the
insulation.
Let it be assumed that a motor is employed of the normal power of 10 horses,
which will start the vehicle and drive it up the incline referred to without over
heating; it will be found that this motor will increase its speed, on the level, at an
undesirable rate and will consume more power than is requisite. Hitherto,
engineers have resorted to artificial resistances inserted between the motor and the
"leads" supplying the current; but, though by recourse to such means, the amount
of current flowing could be regulated, still, such artificial or "idle" resistances are
exceedingly wasteful.
I propose to overcome-to a great extent-the difficulties above indicated, by
employing two, or if desirable, more than two,-motors, which when working
together, will give the requisite power for starting, and for mounting inclines; and,
when working singly, to run on an easy or a level road. These several motors may
be alike in size, or they may be different; but the number of their revolutions is
made to correspond, and the gearing employed for the transmission of their motion, is
arranged accordingly. I so arrange the circuits that by means of a switch or
commutator, the motors may run in "series," in "parallel," or singly, or partly in
"series" and partly in "parallel." I may also arrange the field magnet circuits
distinct from the armature circuits, and join their terminals in a variety of ways
known as in "series" or in "parallel," and thereby vary the resistances of the

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circuit without inserting any
idle" or artificial resistance. The coils of the field
magnets may be wound in either of the manners technically termed "shunt wound,"
and "compound wound," respectively; and, either the whole or part only, of this
winding may be separately excited by means of the battery, or other source of
electricity; and, such separate exciting current may be made to flow in either large
or small quantities, as desired, by either varying the source of current or by varying
the resistance of the wire coils above referred to.
As the amount of current flowing through an Electro-Motor when same is at rest
depends upon the resistance of the wire and field magnets, it is necessary, therefore,
in order to prevent an excessive current being used when starting a vehicle, that the
circuit of the several motors should be arranged so as to give a high resistance, with a
consequent, comparative, low speed. After starting, and as soon as a greater speed
is desirable, the armatures of the several motors or the field magnet coils, or both
the armatures and the field magnet coils may be joined by a switch arrangement of
any known kind, in "parallel or partly in "parallel " or partly in "series." The
speeds, as well as the power, of the motors can be varied in this manner; for, as the
resistance of the whole circuit changes, so also changes the speed of the armatures
when the Electro-motive force of the supply current is constant.
It will be obvious that I may either arrange the several armatures of the motors
on one shaft, or that each motor may be arranged to drive separately, the mechanism
attached thereto.
In order that the nature and objects of my said Invention may be more readily
and perfectly understood, I will now proceed more particularly to describe the same
in its application to tram cars, and for that purpose shall refer to the two Figures
in the accompanying sheet of drawings; the same letters of reference being employed
to denote like or corresponding parts in each.
Figure 1 represents a sectional elevation of a tram car with my Invention applied
thereto; and, Figure 2, a sectional plan view of same. M, M¹ are the motors,-in
the present case two in number,--(although any required number may be employed)
They are shewn in the example illustrated as being supported on bogies A, A,
pivotted at a to the body B of the car, (as described in the Provisional Specification
of my Invention N° 10,215, of even date herewith) the motors, M, M¹, being carried
by frames F, F, supported on the axles b, b. It will be obvious however, that the
motors may be otherwise supported; the particular mode of mounting them, forming
no part of my present invention.
Other
Motion is transmitted from each motor shaft S, to the driving axle by means of
a worm W, engaging with a worm wheel Y, threaded on the axle b, b.
arrangements of gearing may however be substituted in lieu of that shewn.
I prefer to dispose the two motors so that the shaft of one motor drives a forward
axle, and the shaft of the other, an aft axle, as shewn; thus ensuring a firmer grip
upon the rails by multiplying the number of driving wheels. The shafts of the
motors, if in line, may be connected by either a flexible, or by a rigid shaft, as the
case may be. The angle of the worm thread is such as to allow of the free move-
ment of the axles when the current is switched off from the motors. The motors
are reversible, so that the car may be driven in either direction. In cases where a
fine worm thread is desirable, I may provide a clutch which throws the worm
wheel out of gear when the motors are inactive.
The source of the Electric current in the particular application of my Invention
as illustrated in the accompanying sheet of drawings, is a set of Electric batteries C,
placed inside the car, under the seats. The system of propulsion herein referred to,
is especially designed for cars carrying their Electrical energy within same; but,
said system is equally applicable in cases where the Electrical energy is transmitted
through conductors outside the vehicle.
If the car is to be worked from either end, the circuit is arranged in duplicate,
as shewn in the drawings, wherein the circuit is indicated by dot and dash
lines -- marked +, and, marked at the junctions. Either of the com-
mulators R, or R' may be used, and in the following manner :-Metallic connection
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being made by means of plugs or switches, or other known equivalent appliances,
between the metal blocks 6 and 1; 2 and 5; and 3 and 4, the two motors will
work in "series" together. By connecting the metal blocks, 3, 4, 5, and 1, 2, 0,
the pair of motors will work in " parallel"; and, further, if the blocks, 1, 2, and
3, 4, are metallically connected, one of the motors only will be driving, and, the
other will run idle. In following the circuit of the commutator R and the motors
M, M, it will be observed that the + pole of the battery (or other source of
electricity) is joined by a cable or wire to the metal block 3; when 3 and 4 are
joined by a connector, the current of electricity will pass across block 4 to
the pole of the Motor M, circulate through the armature and field magnets
of motor M, and thence pass out at the pole of M to the block 2, across a
connector to block 5, following the cable leading to the + terminal of motor M₁,
through this motor out at the terminal to block 6, which block, when connected
to 1, will complete the circuit with the - pole of a battery, or other source of
Electricity. By following the cables and block connections as indicated above, the
'parallel," and "single" working can readily be traced.-It is obvious that this
system can be extended when more than two motors are to be utilised, by
multiplying the number of metallic blocks and connectors; and, that not only the
whole of the wire coils upon the motors may be simultaneously re-arranged, but the
field magnet coils, separately, may be excited in "series," in "parallel," or in
shunt," as the case may be; and, such excitement may be derived from the main
_circuit or from a branch of the main circuit.
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Under the term "vehicle" as used by me in this-Specification, is intended_and
included, any conveyance, whether wheeled, or not, and capable of travelling either
upon land or water.
When my said Invention is applied to the propulsion of a ship or vessel, the
motors will be caused to act on the screw, screws, or other propelling devices, as
will be well understood.
Having now particularly 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
In the propulsion of tram cars and other vehicles by Electricity, the employment
of two or more Electro-motors having their circuits arranged for varying their
power and speed, all substantially as, herein described, and shewn in the accom-
panying drawing.