Improvements in Electric Traction Apparatus.
Year: 1893

page_text: Date of Application, 28th Aug., 1893
Complete Specification Left, 23rd May, 1894-Accepted, 23rd June, 1894
PROVISIONAL SPECIFICATION.
Improvements in Electric Traction Apparatus.
I, PAUL SCHOOP, of 90 Seestrasse, Zurich, Switzerland, Electro Chemist, do
hereby declare the nature of this invention to be as follows:-
This invention relates to an arrangement of an accumulator battery in combination
with apparatus applicable to any of the known systems of electric traction, in such
a manner as to economise power and provide for emergencies.
As is well known, the fluctuation of the current during the working of an electric
railway is very considerable, the power required at certain times being often twice
or thrice the average power. Consequently the power and generator plant has to
be provided on a large scale, the whole apparatus working on the average at only
half or one third of its working capacity.
Thus the first cost of plant is very high and its working is not of the most
advantageous kind.
A steam engine working with only one third of its full load, is more expensive in
its work than if it were constantly at full load. The same holds good for the
dynamo or electric generator.
It has been already proposed to adopt for electric railways means similar to those
adopted at electric light stations.which are most economically worked, that is to
say, an arrangement of accumulator batteries to take up the electric power at times
when there is little expenditure and to give this stored up current off at times when
the expenditure is greatest. A similar arrangement might be advantageously
applied for electric traction, but, the circumstances being somewhat different from
those of lighting stations, a peculiar arrangement and combination of battery,
generator and line are necessary, the result being that an electric railway can be
worked with a comparatively small power which is continuously charging the
accumulator and this is furnishing the necessary current which may be five times
that produced by the power.
The arrangement consists of the following parts.
1. The motor, which may be an engine, turbine, water wheel or windmill.
2. The electric generator which is a shunt wound dynamo for continuous current.
3. The secondary battery.
4. The electric line.
5. An automatic switch which makes the connection between the dynamo and
the accumulator, when the line does not take up all the current, furnished by the
dynamo so that the superfluous current becomes stored in the battery. This
automatic switch also makes a break between the dynamo and the accumulator
when the line absorbs the whole dynamo current.
6. An automatic self regulating switch for the accumulator battery, to maintain
the tension of the battery at varying loads.
7. An automatic switch like that described as 5 making connection and break for
a small dynamo, used only for charging those cells, connected with the automatic
self regulating switch.
8. An automatic break for the line.
9. A safety fuse between the battery and the line.
The automatic switch (No. 5) is placed in the line from the negative terminal of
the dynamo to the negative pole of the battery and also to the negative wire of
the line. The other automatic switch (No. 7) is placed in the line from the
negative terminal of the small dynamo, to the first cell, belonging to the automatic
regulating switch. The regulating switch is placed at the end of the battery.

page_text: The positive wire of the line is connected with the positive terminal of the
dynamo and the positive pole of the battery whilst the negative wire of the line is
in connection with the negative pole of the battery as well as with the negative
terminal of the dynamo.
The regulating switch is worked by a relay, and two ampère meters and a
voltmeter allow the control of the working of dynamo and battery together.
The automatic switch (No. 5) has a permanent magnet pivotted between two
electro magnets; the one electro magnet excited by the main current, the other
having a fine wire of high resistance in a line connecting the negative pole of the
dynamo to the negative pole of the battery.
When the tension of the dynamo is higher than that of the battery, a current
flows through the fine wire coil and the pivotted magnet is thus attracted whereby
a fork, attached to it is caused to dip into two mercury cups, making thereby the
connection between the dynamo and battery.
When the tension of the dynamo sinks below that of the battery, a current is
again set up in the fine wire coil, but in the opposite direction, from the battery to
the dynamo, and thus the magnet is repelled, causing the fork to rise out of the
mercury-cups and so breaking the connection between dynamo and accumulator.
This action may be repeated many times during every hour when the line is in
operation.
The same action occurs with the other automatic switch No. 7 in connection with
the small dynamo for the regulating cells.
The automatic self regulating switch No. 6 consists of a certain number of
contacts, each connected with one of the regulating-cells with a moveable contact
caused to slide over these by any of the known automatic devices, worked by a
relay, placed between the positive and negative poles of the line. According as
the tension on the line falls below or rises above a certain point, the moveable
contact of the regulating switch is made to slide to the one side or the other,
thereby adding or cutting-out cells of the battery and thus keeping the tension of
the line practically constant.
The battery need not have a very large capacity, as its main merit and work is
to regulate, being constantly charged and discharged at very short intervals, which
may be only a few seconds. At the same time the battery furnishes a reserve for
cases, where a stoppage of the machinery occurs, as it can then provide the line
with the necessary current for a time.
Dated this 28th day of August 1893.
ABEL & IMKAI,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Electric Traction Apparatus.
I, PAUL SCHOOP, of 90 Seestrasse, Zurich, Switzerland, Electro Chemist, 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 arrangement of an accumulator battery in combination
with apparatus applicable to any of the known systems of electric traction, in such
a manner as to economise power and provide for emergencies. As is well known,
the fluctuation of the current during the working of an electric railway is very
considerable, the power required at certain times being often twice or thrice the
average power. Consequently the power and generator plant has to be provided
on a large scale, the whole apparatus working on the average at only half or one
third of its working capacity.
Thus the first cost of plant is very high and its working is not of the most
advantageous kind.

page_text: 4. The electric line.
5. An automatic switch which makes the connection between the dynamo and
the accumulator, when the line does not take up all the current furnished by the
dynamo, so that the superfluous current becomes stored in the battery. This
automatic switch also makes a break between the dynamo and the accumulator
when the line absorbs the whole dynamo current.
6. An automatic self regulating switch for the accumulator battery, to maintain
the tension of the battery at varying loads.
7. An automatic switch like that described at 5 making connection and break
for a small dynamo used only for charging those cells connected with the automatic
self regulating switch.
8. An automatic break for the line.
9. A safety fuse between the battery and the line.
The automatic switch (No. 5) is placed in the line from the negative terminal of
the dynamo to the negative pole of the battery and also to the negative wire of the
line. The other automatic switch (No. 7) is placed in the line from the negative
terminal of the small dynamo to the first cell, belonging to the automatic regulating
switch. The regulating switch is placed at the end of the battery.
The positive wire of the line is connected with the positive terminal of the
dynamo and the positive pole of the battery whilst the negative wire of the line is
in connection with the negative pole of the battery as well as with the negative
terminal of the dynamo.
The regulating switch is worked by a relay, and two ampere meters and a volt
meter allow the control of the working of dynamo and battery together.
I will describe the arrangement and operation of these several parts with
reference to the accompanying drawing which shews a diagrammatic view of the
parts in combination.
I is a suitable motor at the central station which drives a dynamo generator II,
shunt wound for continuous current, III is a secondary battery or accumulator, the
positive lead a of the generator II being connected to the positive pole of the
battery III and both to the positive eonductor a' of the electric railway IV.
The negative terminal of the generator II is connected by a conductor b,
automatic switch V and conductor 6 with the negative pole of the battery III which
is connected through an automatic self regulating switch VI with the negative
conductor or rails 2 of the line through an automatic break VIII.
The automatic switch V consists of a permanent magnet c pivotted between two
electro-magnets d and e, of which d is excited by a fine-wire coil permanently
connected respectively with the negative conductor 6 of the generator and the

page_text: negative pole of the battery III, while the thick wire coil of the other, e is also
connected with the conductor b. With the magnet c is connected a contact arm h
whose fork can make contact with two mercury cups g, thereby connecting the
conductors b b¹. When a current is passing through the fine wire coil of d in the
direction from the dynamo II to the battery III, d attracts the magnet c, and
thereby causes the fork to close the connection, and the current now passing
through the electromagnet e causes this to repel the magnet and thus keep the
arm in the described position. When a current passes in the reverse direction
through the fine wire coil of d, this repels the magnet c, while e attracts it, and
causes the communication between bb to be broken again.
Thus when the tension of the dynamo II is higher than that of the battery, the
switch V will establish the communication between the two and the battery will be
charged with the amount of current from the dynamo in excess of the load on the
railway IV; when, on the other hand, the tension of the dynamo sinks below that
of the battery, a current will flow from the battery to the dynamo throngh the fine
wire coil d, and will thereby break the connection.
This action may be repeated many times during every hour when the line is in
operation.
The automatic switch VI for maintaining the tension of the battery constant
with varying loads consists of a certain number of contacts i, j, k, &c., each
connected with one of the regulating cells i, j, k, of the battery III, and a sliding
contact in connection with the line 6', and caused to slide over the said contacts
by any of the known automatic devices worked by a relay placed between the
positive and negative poles of the line IV, the arrangement being such that
according as the tension on the line falls below or rises above a certain point, the
moveable contact of the regulating switch is made to slide to the one side or the
other, thereby adding to or cutting out regulating cells of the battery and thus
keeping the tension of the line practically constant. The regulating cells i j k &c.
are charged by a small auxiliary dynamo m driven by a suitable motor, one pole of
which dynamo is connected through the lead 6', with the positive pole of the
regulating cells, while the other pole is connected with the negative pole of the
regulating cells of the battery through the automatic regulating switch VII, which
is constructed and operates in precisely the same manner as the switch V, that is to
say, when the tension of dynamo m is greater than that of the battery, a current
passing through the thin wire coil of the electro magnet coil d₁ causes this to
attract the pivotted permanent magnet c', whereby the fork of the arm h¹ makes
contact with the mercury cups g', thus closing the communication between the
dynamo and the battery, this being maintained by the repulsion exercised on
the maguet c' by the electromagnet e¹. When, on the other hand, the tension of the
battery is greater than that of the dynamo, the direction of the current will be
reversed, thereby reversing the switch and breaking the communication between the
dynamo and battery; a fuse IX is provided at n between the battery III and
the line.
The battery need not have a very large capacity, as its main merit and work is
to regulate, being constantly charged and discharged at very short intervals, which
may be only a few seconds. At the same time the battery furnishes a reserve for
cases where a stoppage of the machinery occurs, as it can then provide the line
with the necessary current for a time.
I am aware that it has already been proposed to combine a secondary battery
with the so-called trolley system in order to obtain economical results; also that
there are various arrangements of automatic switches for making and breaking
electrical connections and I do not claim these features as of themselves, constituting
my invention.
By my invention I am enabled to work a tram line with only a fractional
part say one third-of the power necessary for the maximum load of the railway,
which has never been accomplished before, and which enables a great economy to
be effected as compared with the usual system in which powerful engines are

page_text: employed which are capable of producing the maximum power required, and which,.
for the greater part of the time are only working at a fractional part of such
maximum power, and consequently in a very uneconomical manner.
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. In an electric railway, the combination of an electric generator and a secondary
battery arranged in parallel, both having the positive pole connected permanently
with the line by a lead common to both, while the negative poles are connected
with each other and with the line through an automatic switch that connects the
generator with the battery when the tension of the former exceeds that of the
latter, and disconnects these when the tension of the battery exceeds that of
the dynamo, substantially as described.
2. In an electric railway, the combination of an electric generator and a
secondary battery arranged in parallel, both having the positive pole connected
permanently with one pole of the line by a lead common to both, a lead connecting
the negative pole of the battery with the other pole of the line through a break, a
lead connecting the negative pole of the battery with the negative pole of the
dynamo, and a switch on such lead operated by an electromagnet with fine wire
connected to the negative poles of the battery and dynamo whereby the
communication between these is broken when the tension of the dynamo is greater
than that of the battery, substantially as described.
3. In an electric railway the combination of an electric generator, and a secondary
battery arranged in parallel and having their positive poles connected to the
positive pole of the line by a common lead, said battery receiving current from the
generator through an automatic switch, consisting of a pivotted permanent magnet,
a coil of fine wire connected with the negative poles of the generator and battery,
a coil of thick wire connected with the negative pole of the generator and with one
of a pair of mercury cups, the other of which is connected to the negative pole of
the battery, and a fork connected to the pivotted permanent magnet and adapted to
establish contact between the two mercury cups when the tension of the generator
exceeds that of the battery and to break that contact when the tension of the
battery exceeds that of the generator, substantially as described.
4. In an electric railway, the combination of an electric generator, a secondary
battery charged by the generator through an automatic switch, an auxiliary electric
generator connected to regulating cells on the secondary battery by an automatic
switch connecting them when the tension of such generator exceeds that of the said
cells, and a self regulating automatic switch with sliding contacts governed by a
relay between the two poles of the railway, so as to include or cut out regulating
cells of the battery for the purpose of maintaining the tension of the electric
railway practically constant with a varying load, substantially as described.
Dated this 23rd day of May 1894.
ABEL & IMRAY,
Agents for the Applicant..