AN APPARATUS FOR LIGHTING RAILWAY CARRIAGES AND VESSELS WITH COMPRESSED GAS
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Georg Brock at the Office of the
Commissioners of Patents on the 1st November 1877.
GEORG BROCK, of Vienna, in the Empire of Austria, Engineer. "AN APPARATUS
FOR LIGHTING RAILWAY CARRIAGES AND VESSELS WITH COMPRESSED GAS."
This Invention relates to improvements in lighting railway carriages and ships
with compressed gas, and in apparatus for the same, and for the production,
compression, and storage of the gas.
The recent progress in the warming of railway carriages has led me to improve
the method of lighting them also, and to combine the practical experience gained in
both departments.
The lighting of railway carriages by colza, petroleum, and other oils, as hitherto
practised, is objectionable for many reasons, and may with great advantage be
replaced by a more simple, cleanly, and powerful source of light. Gas is certainly
the best medium at present known, and it has already been applied to the lighting
of railway carriages in England, America, Belgium, Italy, and Germany, in
various ways.
In England and Belgium, the gas reservoir has sometimes been placed in the
middle of the train, the gas being conveyed where required by pipes with spiral
connections between the carriages.
In England, the gas has usually been stored at about the pressure only required
at the burner, whereas in Belgium it has been stored in the compressed state in the
luggage van, and emitted to the burners at the required pressure by a regulator in
said van.
In America, each carriage carries its own supply of compressed gas, and is
provided with a special regulator. This latter method has been found to be the
best in practice, as with a single reservoir of gas for the whole train, the lighting of
the carriages is interrupted when the carriages are coupled and uncoupled.
Although this objection has been partially avoided by placing reservoirs on each
carriage capable of furnishing an uninterrupted supply of gas during the coupling
and uncoupling of the carriages, the best mode is to provide each carriage with a
supply of compressed gas.
The application of gas-lighting to railway carriages is facilitated by the use of
gas produced from mineral oils, the residues of tars in general, which gas by reason

page_text: '
of its superior lighting power per unit of volume to that of coal gas is easier of
transport.
A difficulty in the use of compressed gas is the necessity for the employment of a
regulator, which shall be quite unaffected by shocks or oscillations of the carriage
in order to emit the gas from the receivers where it is under a pressure of 10
atmospheres to the burners, at a low uniform pressure suited to its combustion;
also the necessity for works for the production, compression, and supply of gas to
the carriages, which works should not be liable to frequent interruptions for repairs,
&c. The system of my Invention avoids all these objections, and I will describe it
in detail, describing the regulator first as being most important, and then the
arrangement of the apparatus on the carriages; and, lastly, the apparatus for pro-
ducing, compressing, and storing the gas.
In order that the Invention may be better understood, I have illustrat d t by
way of example in the accompanying Drawings, in which,-
Figure 1 represents a plan view; and Figure 2, a sectional elevation of the gas
producing, compressing, and, storing apparatus combined.
Figures 3 and 4 are respectively transverse and longitudinal sections of the
retorts and furnaces.
Figure 5 shows a horizontal section of the regulator; and Figure 6, a top view.
Figure 7, a longitudinal section; and Figure 8, a transverse section of a portion of
the regulator, partly in section.
Figure 9 represents a railway carriage showing the position of the receivers and
the pipes conveying the gas to the lamps.
A is the furnace; B, the hydraulic main; C, automatic apparatus; D, condenser
purifier; E, meter; F, gas engine; G, pump; H, exhaust cock; I, valve of the
compressor; K, L, pipes leading to and from the gas holder; M, O, collector
receivers; P, pipe leading to the columns where the gas is stored.
The regulator consists of a hollow cylinder of metal closed at its base, and at its
upper part by a sheet brass cover or diaphragm having a circular corrugation to:
make it more elastic. To the centre of this diaphragm is connected one end of a lever,
whose other end bears on a valve attached to a piston, the fulcrum of this lever
being placed as near as possible to the valve. The compressed gas escapes from the
receiver between the piston and the valve which it opens, owing to the transverse
area of the valve being greater than that of the piston, and exerts a certain pressure
on the diaphragm, which yields or expands, until by the oscillation of the lever the
valve is closed. This operation is repeated continually as the gas passes from the
regulator to the burners. The flow of the gas is unaffected by shocks or oscillations
of the carriages.
As will be seen in Figure 5, there is a differential pressure between the valve and
the piston, combined with the pressure on the diaphragm. The area of the
diaphragm (the diameter of the valve and piston being given, and pressure of the
gas in the receiver being at 10 atmospheres, and that of the gas emitted at the
regulator being equal to a column of water of 20 millimetres) may be determined
in the following way :-
Let d the diameter of the valve = 20.7m/.
d the diameter of the piston
P
=
20 m/m
m.
the pressure of the gas in the receiver equal 10 atmospheres, or the pressure
of a column of water 100 metres high.
P the pressure of the gas emitted at the regulator a column of water 20m/m.
F the area of the diaphragm.
ƒ the area of the valve 20 m/m 7 diameter
= 336 square m/m

page_text: From the above it results that the pressure P on the diaphragm will close the
lever without the assistance of leverage.
"By the effect of the leverage, and by the aid of a screw at the point of attach-
ment of the lever to the diaphragm, the pressure of the gas escaping from the
regulator may be regulated at will. It will be seen by this with what accuracy
this regulator may be adjusted to work, the mechanism being of greater simplicity
and certainty in its action than any apparatus of the kind hitherto devised. The
regulator works down to an excess of pressure, equal to 1/10 of an atmosphere.
Beneath the carriage frames there is a receiver, whose capacity is determined by
the number of burners, and the length of time they are to be supplied, the said
receiver communicating with the regulator. The receiver consists of a cylindrical
chamber, not rivetted, but of rolled Bessemer steel, the better to resist the pressure
of the gas, having its ends forged solid and.fixed with the aid of tie rods which
traverse the chamber from end to end. In a receiver of this kind. to furnish
enough gas for three burners in each carraiage, each burner consuming 22 litres per
hour, and burning 15 hours, it will be necessary for the storing of the gas,
compressed to 10 atmospheres, that the volume of gas contained should equal
1/10 of a cubic metre, the dimensions being 320 m/m diameter, and 1m 27 length.
For a 30 hours supply two receivers should be used, both. connected to the
regulator.
From the regulator the gas is conveyed to the lamps by a pipe running beneath
up the rear end, and along the roof outside the carriage. At one end of the
receiver there is an inlet valve, and at the other end, the attachment for the
regulator. Upon the pipe at the rear end of each carriage there is a cock, by
which the entire supply may be reduced or cut off without the necessity of turning
off the taps of the lamps, this cock being accessible to the railway employés only.
The lamps differ very little from those employed for lighting with colza oil or
petroleum, and the cost of alteration will therefore be slight. The whole arrange-
ment is represented in Figure 9.
In Figures 1 and 2 of the Drawing, I have represented works for the production,
compression, and supply of gas for six trains, each containing eight passenger
carriages with three lamps, and a goods van with one lamp for a consumption of
30 hours, and each burner consuming 22 litres of gas per hour, corresponding to a
lighting power of 6 or 7 candles. The space occupied by these works is 167 square
metres, of which 147 metres is occupied by the works for gas-making proper,
including the apparatus for compressing the gas, and 20 square metres for the
space for the collecting receiver, which is simply surrounded with masonry without
any other covering.
The gas-making works comprise the furnace, the purifier, and meter, and the
gas holder. The furnace is placed in the first compartment, and encloses three cast
iron retorts strengthened by ribs. The construction of the front and back lids of
these retorts prevents the oil which is introduced at the latter form remaining at
the extremities of the retorts, these parts being cooler than where it is exposed to
the direct action of the flames. The retort settings are so arranged that the flame
does not strike directly against them, so that the retorts may be used for a twelve-
month without being replaced. Each retort may be replaced separately without
interrupting the working of the two others:
The automatic supply of the oil into the retorts is undoubtedly the best method,
as it does not require any supervision and a uniformity of feed is ensured, such
as cannot be attained by any known means. This automatic apparatus consists
of a hermetically closed cast-iron vessel, of such dimensions as will suffice for a
consumption of gas for 24 hours, together with an open receiver placed over the
furnace, and through which two tubes pass, leading from the hermetically closed
vessel, the one for air attached to the upper part, and the other for the supply of
oil attached to its lower part.
The process is as follows:-The closed vessel is in the first place entirely filled
with oil. The open receiver over the furnace is filled by opening a cock on the

page_text: feed pipe up to the point where the two pipes enter the vessel near its upper edge.
When the liquid reaches the height of the two orifices and closes them, all flow
from the closed vessel to the open receiver ceases. If the oil be allowed to flow
from the reservoir into the retort, the tubes will again be opened and the air free
to enter the closed vessel, whereupon the receiver is again filled until the openings
of the tubes are again closed by the liquid, as above described. The flow of the oil
from the receiver into the retorts can be regulated by means of cocks provided with
dials or quadrants, and it is perfectly uniform during the entire period of the gas-
making, the column of liquid being in consequence of the automatic refilling always
of the same height.
Upon the front of the furnace is placed the hydraulic main, into which the
ascension pipes lead from each retort. This serves to prevent the return of gas
from the holder to the retorts when one of them is opened during the gas-making,
and also to collect the particles of tar mechanically suspended in the gas. Pipes
lead thence to the purifiers. These are composed of a chamber divided by a
partition, and in one of the compartments the coke is placed and in the other the
sieves or trays placed one on top of another, and covered with Laming's compound.
By a simple arrangement of valve, the passage of gas through any purifier may
be cut off during the production of the gas. From these purifiers, pipes having a
rotary meter attached lead to the gas holder, which is located in a covered place,
and is of a suitable height and capacity. The gas passes from the gas holder to a
compressing apparatus, where it is subjected to a pressure of 11 atmospheres and. 1/2,
by means of water forced into two receivers by pumps, in such manner that the
water is constantly forced from one receiver into another filled with gas, this
operation being continued until the pressure of the gas equals 11 atmospheres
and 1/2.
It is not advantageous to pump the gas directly, this involving a great speed of
the piston, and consequently a heating of the parts and frequent repairs. To prevent
freezing glycerine is added until the mixture marks 11° Baumé.
From the collecting receivers the leads to the stand pipes or columns at which
the carriages are filled and which are placed a carriage length apart, the gas being
conveyed thence to the carriage reservoirs through leather hose furnished with
suitable coupling attachments. These columns or stand pipes may be provided
with suitable stop valves; the collecting receivers are in connection with one
another so as to form a whole. For the working of the entire apparatus, two
Lenoir gas engines of 2 horse-power, 2 pumps with pistons of 80 m/m diameter and
240 /m stroke, and a delivery of 8.4 cubic metres per hour.
m
All the receivers are constructed of rolled Bessemer steel with strong ends
secured by tie bolts. The apparatus being for the most part in duplicate and
capable of being disconnected and worked singly, interruptions in the supply of
gas are not likely to arise.