An Improved Method of Distributing Electricity for Lighting Railway Trains.
Year: 1889

page_text: Date of Application, 15th Mar., 1889
Complete Specification Left, 14th Dec., 1889-Accepted, 25th Jan., 1890
PROVISIONAL SPECIFICATION.
An Improved Method of Distributing Electricity for Lighting
Railway Trains.
We, WILLIAM LLEWELLYN PREECE Electrical Engineer of 38 St. James Terrace
London Road Derby in the county of Derby and JOSIAH SAYERS Electrical Engineer
of 24 Glycena Road Lavender Hill S.W. in the county of Surrey do hereby declare
the nature of this invention to be as follows:-
This invention relates more particularly to the lighting of railway Trains by
electricity. Each coach in the Train carries a separate set of accumulators which
are sufficient to give light to the lamps therein for a definite time. Hitherto in
such cases the lamps have been joined up directly with the accumulators by which
they are fed, the dynamo machine not being included in simple circuit with them.
Under this arrangement the lamps become brighter than is desirable when the
batteries are being charged.
In the method adopted by the inventors this difficulty is obviated. The lamps in
each coach are here connected up in parallel to a pair of mains one of which
terminates in a coupling outside the coach at one end and the other in a similar
coupling at the other end of the coach.
In like manner the battery being joined up in series has its poles terminating in
two couplings one each end of the coach.
There are thus four free coupling terminals two at each end of the coach and in
making up a train these are joined from coach to coach the final pair of couplings
being joined across so as to put the batteries and their respective sets of lamps all in
series. The dynamo is preferably one which keeps a practically constant E. M. F.
under considerable variations of speed and has in its field magnet circuit an automatic
switch actuated preferably by centrifugal force and by which the circuit is broken
either when the speed exceeds one limit or falls below another; these limiting speeds
being determined by the character of the machine. By this device any sensible
increase or decrease in the brightness of the lamps is avoided.
A switch with an adjustable resistance coil is also inserted in the field magnet
circuit by which the initial E. M. F. may be controlled or entirely stopped.
When the field magnet circuit is thus broken the lamps are fed through the
armature of the dynamo from the batteries alone. The connections may be modified
by permanently joining one of the lamp mains to one of the battery terminals in
each coach, the second lamp main terminating outside the coach in two couplings
one at each end. The second battery main is also terminated by two similar
couplings one at each end of the coach. Thus when the train is made up the battery
and lamps in each coach are in series with each other, the combinations being in
parallel. The final couplings are in this case left free. Low resistance lamps may be
used and joined all in series to take the place of the parallel set of lamps in the
above connection. :
Dated this 15th day of March 1889
W. LLEWELLYN PREECE.
JOSIAH SAYERS.

page_text: COMPLETE SPECIFICATION.
An Improved Method of Distributing Electricity for Lighting
Railway Trains..
We, WILLIAM LLEWELLYN PREECE, and JOSIAH SAYERS, 24 Glycena Road,
Lavender Hill, 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 more particularly to the lighting of railway trains by
electricity.
Each coach in the train carries a separate set of accumulators which are sufficient
to give light to the lamps therein for a definite time. Hitherto in such cases the
lamps have been joined up directly with the accumulators by which they are fed,
Under
the dynamo machine not being included in simple circuit with them.
this arrangement the lamps become brighter than is desirable when the batteries
are being charged.
In the method adopted by the inventors this difficulty is overcome. The lamps
in eich coach are here connected up in parallel to a pair of mains, one of which
terminates in a coupling outside the coach at one end of the train and the other in a
similar coupling at the other end of the coach.
In like manner the battery being joined up in series has its poles terminating in
two couplings one at each end of the coach.
There are thus four free coupling terminals, two at each end of the coach, and in
making up a train these are joined from coach to coach, the final pair of couplings
being joined across so as to put the batteries and their respective sets of lamps all in
series. The dynamo is preferably one which keeps a practically constant electro-.
motive force under considerable variations of speed, and has in its field magnet
circuit an automatic switch actuated preferably by centrifugal force, by which the
circuit is broken either when the speed exceeds one limit, or falls below another,
these limiting speeds being determined by the character of the machine.
By this
device any sensible increase or decrease in the brightness of the lamps is avoided.
A switch with an adjustable resistance coil is also inserted in the field magnet
circuit by which the initial electro-motive force may be controlled or entirely
stopped.
When the field magnet circuit is thus broken, the lamps are fed through the
armature of the dynamo from the batteries alone. The connections may be modified
by permanently joining one of the lamp mains to one of the battery terminals in each
coach, the second lamp main terminating outside the coach in two couplings one at
each end; the second battery main is also terminated by two similar couplings one
at each end of the coach. Thus, when the train is made up, the battery and lamps
in each coach are in series with each other, the combinations being in parallel. The
final couplings are in this case left free.
Low resistance lamps may be used and joined all in series to take the place of the
parallel set of lamps in the above connections.
Fig. 1 of the accompanying drawings represents diagrammatically the arrangement
first above described of the lamps L and the storage batteries B in three coaches A
of a train, and their connections with one another and with the dynamo D.
The main lead of the batteries B is connected to one terminal of the dynamo D
and is coupled from coach to coach by external couplings C. The lead for the
lamps L, which in each coach are connected parallel, is connected to the other
terminal of the dynamo D and coupled from coach to coach also by external
couplings C. The two leads at the end of the train are connected together by a
coupling C¹.
Thus, all the batteries are in series and the sets of lamps in the successive coaches
are in series.
Fig. 2 shews diagrammatically the modified arrangement in which the batteries B

page_text: in the successive coaches are derived parallel from the one main lead, and the sets of
parallel connected lamps L are also derived parallel from the other main lead.
In this case the leads at the end of the train are not connected.
As shewn in Fig. 3, the batteries B are connected in series as in Fig. 1, and the
lamps L are also all in series.
Again, as shewn in Fig. 4 in which the lamps L as well as the batteries B
are derived parallel from the main leads, the lamps in each coach are in series.
In the arrangement shewn in Fig. 2 the number of cells in each battery B, being
determined by the volt power of the lamps employed, should be the same.
In the arrangements shewn in Figs. 3 and 4 the number of cells in each battery
should be proportioned to the number of lamps in the samo coach.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what we
claim is
1. The arrangement of dynamo machine, conductors, storage batteries and lamps
for lighting a railway train. substantially as described with reference to Figs. 1 and 3
wherein the batteries in the successive coaches and the groups of lamps are
connected in series respectively in two main leads connected to the terminals of
the dynamo.
2. The arrangement substantially as described with reference to Figs. 2 and 4
wherein the battery and lamps in each coach are in series derived from the two main
leads of the dynamo.
Dated this 11th day of December 1889
ABEL & IMRAY,
Agents for the Applicants.