Improvements in or relating to Electrically Propelled Vehicles.
Year: 1898

page_text: Date of Application, 28th Sept., 1898-Accepted, 7th Jan.,
1899
COMPLETE SPECIFICATION.
Improvements in or relating to Electrically Propelled Vehicles.
I, ROBERT WINTHROP BLACKWELL, of 39, Victoria Street, in the City of
Westminster, Electrical 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 electrically propelled vehicles employing storage batteries
or accumulators carried by the vehicle and has for its object the providing of an
arrangement of batteries motors & a switch or controller for making the necessary
electrical connections for the control of said vehicle.
By the proposed arrangement a suitable number of variations in speed are
obtained in a simple and cheap. manner with an increase of efficiency over the
simple rheostatic control.
Also this arrangement permits of several degrees of braking effect to be
obtained.
This invention shows how, by dividing the batteries into two equal groups, a
large number of series and parallel combinations may be obtained with the use of a
simple switch or controller.
.
(
I will now describe my invention by reference to the accompanying drawings.
For making the hereinafter described connections a controller or switch is
employed consisting of a revolvable non-conducting cylinder carrying contacts as
shewn developed in Figure 3 against which contacts a series of contact studs are
adapted to press after any one of the methods commonly employed in such well
known constructions.
.
2:
Figure shews diagrammatically the combinations of batteries, motors and
resistance that are made, the armatures and fields being indicated in the conventional
way.
Figure 2 shews the connections which are made to the contact studs of the
controller, each contact stud being shewn in its position relative to the revolvable
contacts.
Figure 4 is a development of a section through a ratchet or star wheel secured
to, or connected with the switch cylinder for checking the latter when it reaches;
and retaining it in, its various operative positions.
Like reference letters and numerals indicate like or corresponding parts
throughout the drawings.
In carrying my invention into practice as shewn in the drawings, I provide two
storage batteries A A¹, and electric motors having two sets of arinatures and
commutators B1 B2 conveniently mounted on the same shaft and corresponding
field coils bb, a suitable resistance C. and a switch or controller D D¹ all of the
devices being so arranged and connected that, besides the stopping, or inoperative;
position, nine different conditions of working are provided for, as hereinafter
particularly described.
The switch or controller DD' comprises two relatively adjustable parts of which one
carrying the contact studs is marked D and herein called a "stud plate" and the other
is marked D' and herein called a "switch cylinder." The stud plate D is provided
F

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with thirteen contact studs a, b, c, d, e, f, g, h, i, j, k, l, and m, these studs being
connected to the storage batteries, motor and resistance in the following manner.
The positive poles of the batteries A A¹ are respectively connected to the studs a
and by conductors a¹, a² and the negative poles are respectively connected to the
contact, studs m aud k by the conductors a³ at; the terminals of the resistance C
are respectively connected to the contact studs a and b; the terminals of the motor
field coil b are connected to the contact studs c and d and the terminals of the
motor field coil b2 are connected to the contact studs e and f; the terminals of
the armature coil B, or the brushes constituting these terminals, are connected to
the contact studs g and h, and the terminals of the armature coil B², or the brushes
constituting the said terminals are connected to the contact studs i and j.
On the surface of the switch cylinder D', as shewn in Figure 3, are provided a
number of contact blocks which are so arranged, that at different parts of the
rotation of the said cylinder, they will be caused to make contact with some or all
of the before described studs of the stud plate D according to the particular
direction in, or speed at, which it is desired the vehicle shall be propelled.
As previously mentioned there are nine different conditions of working of the
apparatus besides the stopping or inoperative position and these ten different com-
binations are diagrammatically represented in Figure 1 wherein they are respectively
marked with the Roman numbers I, II, III, IV, V, VI, VII, VIII, IX, and X; the
different parts or segments of the surface of the switch cylinder D¹, brought into
use to obtain these various combinations, are in Figure 3 respectively marked with
corresponding Arabic numerals and these seginents are preferably of the circum-
ferential lengths indicated in Figure 4. In this last named figure the recesses of the
ratchet or star wheel E for arresting the said switch cylinder in its various positions
bear reference letters having index numerals (1 to 10) similar to those on the
respectively-corresponding parts of the switch cylinder D¹.
When the vehicle is at rest the part 1 of the switch-cylinder D₁ is presented to
the stud-plate D, and as there are no contact blocks at this part of the switch
cylinder no electrical circuit is established, as shown at 1, Figure 1, the recess e¹ of
the ratchet or star wheel E serving to retain the cylinder D' in this position for any
desired period. When it is desired that the vehicle shall be propelled forward
the switch cylinder D¹ is turned so as to present the part 2 thereof towards the
stud plate D in which position, through the contact blocks 2n, 2º, 2º, 2º, 25, and 2
and all of the contact studs a to m, the batteries AA¹ are connected in parallel
and the resistance C and field and armature coils 61 62 B1 B2 are connected in series
as shewn at Il in Figure 1, with the result that a big current and consequently
big starting torque are obtained; the ratchet wheel recess c² serving to retain the
switch cylinder D' in this position for any desired length of time. The motor will
then propel the vehicle forward at its minimum speed. The forward speed of the
vehicle may then be gradually increased through the III, IV, V, and VI stages
until the maximum stage (VII) is reached.
When the switch cylinder is moved so that the part 3 thereof is presented
towards the stud plate D the contact blocks 3", 2º, 2º, 2º and 2 cause the
last described circuit to be maintained but with the resistance C short-circuited,
as shewn at III Figure 1, the result being that a bigher speed is obtained
without wasteful consumption of electrical energy there being no idle resistance
presented to the passage of the current. The recess 3 of the ratchet or star
wheel E serves to retain the switch cylinder D₁ in the last named position for any
desired length of time.
When the part 4 of the switch cylinder D¹ is presented towards the stud-plate D
the contact blocks 4" 4° 4 4 4 4 and 4, the first and last of which are
electrically connected together by a conductor 4 by making contact with the studs
b, c, d, e, f, g, h, i, j, k,l and m serve to connect the batteries A A¹, field and
arinature coils bb2B B2 and resistance C all in series, as shown at IV in Figure 1,
with the result that, owing to the greater electro-motive force then available a higher
speed is obtained.
t

page_text: When the part 5 of the switch cylinder D' is presented towards the stud-plate D.
the contact blocks 4º, 5º, 5º; 4, 4, 48 and 4 and all of the contact studs a to m
cause the last described circuit to be maintained but with the resistance C cut out
therefrom as shewn at V in Figure 1 so that the vehicle is propelled at a greater
speed with no useless expenditure of electrical energy.
When the part 6 of the switch cylinder is moved into its effective position the
contact blocks 6º, 6º, 6º, 6º, 6, 7, 6 and 6, in conjunction with all the contact studs,
connect the field coils in series, the armatures in multiple and the batteries in series
the résistance being cut out. The blocks 69 and 6 are electrically connected by a
conductor 6 and the blocks 7 and 6s are also counected by the conductor 7. Also
6 and 6 are likewise connected by conductor 4 in connection with the blocks 4"
and 4 with their joining pieces 6b.
To obtain the maximum forward speed the switch cylinder is turned into its
seventh position so as to place the blocks 6", 7", 7", 7", 64, 6, 7, 65 and 6 in
contact with all the studs u to m. The blocks 7 and 7° are electrically connected
by à conductor 7, the blocks 7º, 6º and Gr are electrically connected by the
before mentioned conductor 6" and the blocks 7 and 6 are electrically connected
by a conductor 7. By this arrangement tho batteries A A¹ are connected in
series, the field and armature coils 12 B¹ B2 are connected in parallel and the
-resistance C is cut out of the circuit as shown at VII in Figure 1.
Throughout the foregoing stages the switch cylinder D₁ has been turned always
in the same direction and when it is desired to stop or reverse the motion of the
vehicle after the cylinder has been thus operated the said cylinder must be turned
in the reverse direction so that these several stages may be passed through in
the reverse order.
When it is desired that the vehicle should stop without the application of the
brake power which the before described apparatus is capable of exercising, or of
allowing the said vehicle to proceed by its own momentum as when travelling down
an incline, the switch cylinder D¹³ is turned into, and retained in the position in
which the part.1 thereof is presented towards the stud-plate D so that the
electrical circuit is broken. When however it is necessary to apply brake power
to arrest the progress of the vehicle the switch cylinder D¹ is turned so that its
part 8 is presented towards the stud-plate D, in which position the blocks 8" 8" 8r
84 8 8 and 8 (of which the blocks 8" and 8" are electrically connected by a
conductor 8 and the blocks 8 and 8 are electrically connected by a conductor 8")
in conjunction with the contact studs a, b, c, d, e, f, g, h, i, and j, connect one
of the field coils and the corresponding armature coil with the other of the field
coils and its corresponding armature coil in such manner that each motor generates
an electro-motive force in such a direction that a current is caused to circulate
through the two motors and through the resistance C thereby creating a powerful
force for retarding the vehicle; in this position of adjustment as shown at VIII
Figure 1 the batteries are entirely disconnected.
When the maximum braking power is to be applied the switch cylinder D¹ is
moved so as to present its part towards the stud-plate D, in which position the
blocks 8, 9, 8, 8, 8, 8% and 8t (of which the blocks 8", 9" and 8" are electrically
connected by the conductor 8ª and the blocks 8 and 8 are, as hereinbefore
described electrically connected by the conductor 8b) by making contact with the
contact studs a, c, d, e, f, g, h, i, and j cause the batteries to remain disconnected
as in the first braking position VIII Figure 1, and the resistance C to be cut out
from the circuit as shewn at IX in Figure 1, consequently because of the decreased
resistance of the circuits of the motors now acting as generators the current greatly
increases and the braking effect also, correspondingly increases.
When it is desired that the vehicle shall travel backwards, the switch cylinder is
turned into its tenth position so as to bring the contact blocks 10", 10°, 10P, 10%,
10, 10, 10 and 10 (of which the blocks 101 and 10" are electrically connected
together by a conductor 10 and the blocks 10 and 10t are connected by
conductors 10 to the before described electrically-connected blocks 8 and 8t

page_text: respectively) into contact with all of the studs a to m so that the batteries AA¹ are
connected in parallel and the field and armature coils b¹ 62 B1 B2. and resistance C
are connected in series as shewn at X in Figure 1 the current then passing through
all the coils in such a direction as to drive the motors backward.
The star-wheel E is so constructed that the switch cylinder D¹ cannot be turned
from the last described or tenth position directly into a forward driving position, it
being necessary, before the latter result is obtained, to turn the said cylinder
through the various intermediate positions so that the change between the different
conditions of working is gradual and the risk of overheating, or burning the motor
coils or otherwise injuring the apparatus is rendered very small.
The hereinbefore described apparatus may be modified without departing from
the essential features of the invention, for example instead of the stud-plate D
constituting the fixed part, and the switch cylinder D¹ constituting the moveable
part, of the switch or controller, which is the preferred construction, it will be
obvious that the reverse of this arrangement may be employed. Instead of these
two motors having one common shaft they may each have an independent shaft
which may be connected to the others by any suitable power-transmission gear.
Also it is evident that instead of using two motors there may be employed one
motor having two armature windings and two field coils corresponding parts being
correspondingly connected.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the sume is to be performed, I declare that what I
claim is :-
1. In an electrically-propelled vehicle the combination of two electric motors or
a single motor having two armature windings and two sets of field windings, with
two storage batteries, arranged and operating substantially as hereinbefore described
with reference to the accompanying drawings.
i
2. In an electrically-propelled vehicle, with two batteries, the arrangement of
two motors or a single motor with two armatures and two field windings, so that the
motors or motor may serve to propel the vehicle or to act as generators or a
generator substantially as and for the purpose herein before described.
*
3. In an electrically-propelled vehicle the combination of two electric batteries,
two electric motors or a single motor having two armatures and two field windings,
a resistance and a switch or controller substantially as hereinbefore described and
illustrated in the accompanying drawings.
Dated this 28th day of September 1898.