Improvements in or relating to Switch Devices for Electric Tramways.
Year: 1898

page_text: Date of Application, 13th Aug., 1898
Complete Specification Left, 24th Apr., 1899-Accepted, 27th May, 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to Switch Devices for Electric
Tramways.
I, DR. ERNST ANDREAS, of 105-107, Rosenstrasse, Dresden, in Germany,
Electrician, do hereby declare the nature of this invention to be as follows:-
This invention relates to an automatic switch device for electric tramways of
a "mixed" kind i.e. such which work partly with an overhead conductor or
one coming in at the bottom and partly with storage batteries.
The novelty chiefly consists in a resistance being automatically switched in
on the overhead or bottom conductors at the start or in the accumulator circuit
at the beginning of re-charging. This is done in order to equalize the conditions
of charging and discharging on different portions of the line.
By switching in a resistance it is chieny intended to prevent the strength of
the current at the beginning from exceeding a certain maximum, as accumu-
lators must be charged at a constant pressure, and it is also intended to prevent,
by switching in resistances, to prevent the discharge of accumulators into the
overhead or bottom conductors during unavoidable frequent oscillations of the
tension occurring in the said conductors. In this way the generation of gas in
the accumulators at the end of discharge is avoided. The switching device
according to this invention is arranged so that switching-in or out of the resis-
tances is effected automatically in so far that by the manipulation of the contact-
lever, the switching device is simultaneously operated.
The contact lever is connected in the usual way to the automatic device and
the controller and the motor, by a conductor. Some incandescent lamps are
used for lighting and some as resistances and are connected together by a con-
ductor. A separate resistance is used for the switching in into the accumulator
circuit.
The device according to this invention is chiefly constituted by two metallic
segments electrically connected and secured to a contact-lever or to a bar carry-
ing contact rollers, so that said segments and contact lever turn together.
Near the centre of rotation of the contact lever and in the plane of rotation of
the latter is arranged a spring connected by a wire to the storage batteries. This
spring is mounted on the roof of the tram-car by means of a spring-controlled
hinge-joint. In a recess of this spring there is pivotally mounted a second spring
insulated from the first by means of a frame of vulcanised rubber and a sleeve
of the same material. This second spring is connected by a wire with the wire
of the lamp-circuit in such manner, that the lamps (used as resistances) can be
short-circuited by means of said wire and switched out.
When the contact lever is in such position that the segments do not touch the
springs the parts are completely insulated from each other. The current from
the overhead wire passes through the contact lever into the automatic device
then branches off into the wires, the first of which leads to the controlling device

page_text: and the motor, the second to the lamps used for lighting, the current having to
pass the resistances (lamps) and the third wire to the storage batteries, the current
having to pass through the storage battery resistance. The wire from the inner
spring and the wire between the storage battery and contact plate do not form
in this case a part of the circuits.
When it is desired to change from the overhead line driving to accumulator
driving, the contact lever is pulled to one or to the other side, then one of the
metallic segments, strikes the springs. As the contact surface of the segments is
as wide as the first or outer spring, there is a contact made between the springs
and the segment. The secondary current from the accumulator then follows the
following path. It passes through the wire between the storage battery
and contact plate-thus short circuiting the resistance into the outer spring.
where it branches off, one brauch going through the segment to the automatic
device and thence to the controller and motor and finally to earth, the second goes
through the segment to the inner spring and through the wire-the resistance-
lamps being short-circuited-directly to the incandescent lamps for lighting,
whence it also passes to earth. The resistance and the resistances-lamps are
switched out simply by moving the contact lever, and the circuit is arranged for
driving by means of accumulators without necessitating any additional manipula-
tions.
It must be also mentioned that the applicant does not limit himself to the con-
struction described by way of example which is only an example of carrying into
effect this invention, but reserves to himself the right of making modifications
in construction.
19th
₤
1000
BOULT & WADE,
Agents for the Applicant.
Improvements in or relating to Switch Devices for Electric
Tramways.
I, DR. ERNST ANDREAS, of 105-107, Rosenstrasse, Dresden, in Germany,
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;-
-
This invention relates to an automatic switch device for electric tramways
working upon the "mixed power" system, that is to say, working sometimes
with power derived from an overhead or underground conductor and sometimes
obtaining the power from storage cells.
The novelty chiefly consists in a resistance being automatically inserted when
the power is derived from the line in order that an excess of current shall not
be passed through the storage cells. Other resistances may also be inserted as,
for example, in series with the lamps lighting the car.
The presence of the resistance in the accumulator circuit when the power is
derived from the line, tends to prevent a harmful discharge of current from the
cells into the line during the unavoidable variations of the pressure in the line.
In this way also the generation of gas in the accumulators at the end of dis-
charge is avoided.
The switching device according to this invention is so arranged that the resist-
ances are inserted or cut out automatically in so far that by the manipulation of
the contact lever the switching device is simultaneously operated.

page_text: In the accomp
ng arawn
Figure 1 is a side elevation showing diagrammatically a tramcar provided
with switch device according to this invention.
Figure 2 is a diagram showing the switching device and the circuits and
apparatus connected with it.
Figure 3 and 4 are elevations showing in detail the construction of portions of
the switching device.
Like letters indicate like parts throughout the drawings.
a is a collecting arm or contact lever by which current passes from the con-
ductor, an overhead line in this particular instance,-through an automatic
device A and controller C to the motor M; these latter portions of the apparatus
form no part of the present invention, and therefore, are not fully described.
k is a conductor joining the collecting arm with the previously mentioned motor,
controller, etc.
Some incandescent lamps 9 are used for lighting the car, and when the current
is derived from the line they are placed in series with a resistance, in the form
of additional lamps f to prevent over-running. The lamps f are connected to
the conductor k by the wire m and another wire m¹ serves to connect the lamps g.
The storage cells are shown at E, and W is a resistance which is always in series
with them when they are charged by a current from the line.
The device according to this invention is chiefly constituted by two metallic
segments a¹ a², electrically connected and secured to the collecting arm a so that
the segments and the collecting arm move together about a common axis. In
the path through which the segments a¹ a² move when rotated is a spring con-
tact b, connected by a wire h to the storage cells E. The spring 6 is con-
veniently mounted upon the roof of the tram-car by means of a spring controlled
hinged joint. A second spring c is pivotally mounted within a recess in the face
of the spring b, being insulated from the latter by vulcanised rubber as at d
and e (Figure 4). This second spring c is connected by a wire i to a point in
the lamp circuit between the lamps f and g, in such a manner that the former,
which are used as resistances, may be short circuited or cut out by the wire i
as hereinafter described.
When the switch device is in the position shown in Figure 2, the current passes
from the line through the device A and then branches off, one portion going by
means of the conductor k through the controller C and motor M, while the other
portion again splits one part passing by the conductor m through the lamp resist-
ances to the lamps g, and the other part going through the wire'w and resist-
ance W to the storage cells E. It will be seen that in this position the springs b
and care quite insulated from the contact segments a¹ à³, and therefore the
wires i and h are inoperative.
When it is desired to drive the car from the storage cells instead of from the
line, the collecting arm a is pulled to one side or the other, thus causing one
The
of the contact segments a¹ a² to make contact with the springs 6 and c.
face of the contact segment is sufficiently wide to make electrical connection
between itself and the two springs 6 and c. The current from the storage cells E
now takes the following path:
It passes through the conductor h thus cutting out the resistance W, into the
spring b, here it divides one portion going through the contact segment a¹ or a²
through the conductor k to the motor M and other apparatus, the other portion
going through the spring c and wire i to the lamps g, the resistance lamps f
being short circuited. The motor M, lamps 9 and storage cells E, are all con-
nected to earth as shown diagrammatically in Figure 2. It will be seen that
by simply moving the collecting arm or contact lever a the resistances W and f
are automatically switched in or out, and the car driven by current either from
the line or from the storage cells.
It is to be understood that this invention is not limited to the particular con-

page_text: struction herein described, it being obvious that various modifications may be
made without departing from the spirit of the invention.
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: :-
1. A switch device for use on a "mixed power" electric traction system
characterised by a resistance in circuit with the accumulators when power is
derived from the line being short circuited when power is taken from the storage
cells.
2. A switch device for use on a "mixed power" electric traction system in which
the disengagement of the collecting arm from the line serves to throw the storage
cells into action and at the same time short circuits resistances previously in
circuit with the cells and the lamps.
3. In a switch device for use on a "mixed power" electric traction system
the combination with the collecting arm of contact segments or equivalents
whereby the storage cells are put in circuit with the motor, and a resistance short
circuited substantially as described.
4. A switch device for use on a "mixed power" electric traction system
characterised by contact segments a¹ a² fixed to the axle of the collecting arm,
contact springs b c insulated from each other and arranged in the plane of rota-
tion of the segments, one spring being connected to the storage cells and the
other c connected to lamps g so that when the collecting arm a is withdrawn
out of contact with the line one of the segments a¹ a² comes into contact with
the springs b and c and short circuits resistances W and f which have been
respectively in series with the storage cells and lamps.
Dated this 24th day of April 1899
BOULT & WADE,
Agents for the Applicant.