Improvements in Compressed Air Locomotive Carriages
Year: 1896

page_text: Date of Application, 18th Dec., 1896
Complete Specification Left, 7th Aug., 1897-Accepted, 4th Dec.. 1897
PROVISIONAL SPECIFICATION.
"Improvements in Compressed Air Locomotive Carriages."
I, VICTOR POPP of 80 Rue Taitbout, Paris, France, Engineer; Do hereby declare
the nature of this Invention to be as follows:-
This Invention relates to a compressed air locomotive carriage specially arranged
with a view to simplicity, compactness, and the utilization of compressed air in the most
efficient manner. The engine which is carried upon a single framing of special
construction, comprises two cylinders of different diameters for compound working
but capable of simple working when increased power is required, in which case the
system of distribution forming the subject of previous Letters Patent is employed.
Reversing is effected by admitting compressed air to one or other side of a small
auxiliary piston which actuates the slide valves. The compressed air is heated
before it enters each of the cylinders, by means of small heaters having a large
surface heated by a separate furnace under forced draught of air injected from the
exhaust. The admission of compressed air is regulated so as to obtain any desired
speed of the driving pistons at all times, by means of a Meyer Expansion Gear, in
order that the compressed air may do its work in the most efficient manner. The
compressed air reservoirs are charged at certain points of the journey, by means
of my improved automatic feed apparatus forming the subject of a former Patent.
Reference is to be had to the accompanying drawings, in which
Figure 1 represents a side elevation of the locomotive carriage.
Figure 2 is a plan of the engines with the body and floor of the car removed.
Figure 3 is a plan of the handing gear.
Figure 4 is a cross-section on line 1-2 Figure 2.
Figure 5 is a side elevation of the framing which carries the engines.
Figure 6 is a vertical section of the air heater furnace.
Figure 7 is a vertical section of the air heater.
Figure 8 is a vertical section of the draught nozzle for the air heater furnace.
Figure 9 is a cross section of the distribution cocks.
Figure 10 is a vertical section and plan of a regulator placed in front of the
cylinders.
Figure 11 is a diagrammatic view shewing a modification of the compressed air
distribution to the various parts.
The saine letters of reference denote like parts in all the Figures.
a is the frame of the under carriage carrying the engines and other parts of the
mechanism and 6 is the frame carrying the body of the vehicle and the compressed
air reservoirs hung from the underside of the floor. By this arrangement the
vibration of the engines is not communicated to the carriage body and the wheel
axles may be brought closer together without affecting the stahility of the car.
The springs of frame a are very stiff so that this frame always remains nearly
horizontal while the points of support of frame b upon frame a being far apart
greater stability is obtained although the interposed springs are flexible. The axles
nay thus be brought so close together as to be able to run in curves of very small
radius. The engines are carried by a single frame c carrying the crosshead

page_text: guides d, d, one end of the frame being supported by two bearings upon the
axle e and the other upon a spring on the frame a or directly upon said frame.
Upon axle is keyed a toothed wheel g. driven by a pinion gl, keyed on the
crank shaft turning in bearings carried by frame e and having two cranks at
90 degrees operated by the two pistons. The speed of the engines with regard to the
vehicle wheels therefore depends upon the ratio of the gear g, 9', which is enclosed
in a dust-tight casing and may ran in a bath of oil. The cylinders k, l, are of
different diameters to admit of compound working by the smaller cylinder
exhausting into the larger cylinder. When, however, extra power is required or
in case the small piston be at the dead point at starting, the pressure may be
admitted directly to both cylinders by a special arrangement of cocks.
The compressed air is supplied to the reservoirs ma through the inlet n, by means
of the self-acting feed apparatus forming the subject of a previous Patent. The
compressed air before adinission to the cylinders is heated hy passing through the
heaters o, o, ench consisting, as shewn in Figure 7, of a series of serpentine
tubes a through which the air circulates, the tubes being fixed in a casing p
provided with baffles g through which cirenlate the products of combustion from a
furnace r. To accommodate as many tubes as possible they are fixed as follows:-
The tube ends are screw-threaded and provided with back nuts t and cap nuts u
having square holes v to receive a key for screwing up the caps, tight joints being
ensured by asbestos or other suitable packing. By this mode of fixing the tubes
may be placed very close together and a large heating surface obtained in a small
space. The inlet and outlet ¹ for the compressed air have a sectional area equal
to the aggregate internal sectional area of the tubes 8. y is the inlet and y' the
outlet for the heated gases from the furnace and on leaving the second heater
they are conducted to an apparatus hereinafter described for promoting the
draught. The heating furnace r, shewn in Figure 6, is closed and fed automatically
from a container z of a size to work for one day without re-charging. The ash-
pan 1 has openings 2 regulated by dampers 3 controlled by a lever 4 and links 5
to regulate the admission of air for combustion. A double inclined deflector 6 is
provided to deflect the air upwards to the bars in whichever direction the car is
travelling. The furnace gases after having traversed each of the heaters are
expelled by means of a forced diaught produced by the exhaust air from the engines,
for which purpose the exhaust from each of the cylinders after being expanded down
in a chamber 7 (Figure 2) is conducted through a pipe 8 (Figure 8) and blast
nozzle 9 into a pipe y2 which receives the furnace gases, the area of the nozzle
being regulated by the cone 11 adjustable by the knob 10. The gases are thus
discharged continuously into the atmosphere since the exhaust air is also continually
escaping owing to its expansion in the chamber thus preventing shocks and
reducing the velocity of the escaping air. When the engines are not working, a
draught of air is obtained by a jet of compressed air supplied through the passage 12
to the annular nozzle 13 around the nozzle 9. The supply of compressed air is
,effected automatically, the air on entering the receiving inlet n is admitted by
lifting the check valve in the box 14 (Figure 2) which communicates with
. reservoirs m by pipes 15 and 16, and the flexible pipes attached to their ends 17 and
18. The compressed air on leaving the reservoirs m passes to the heaters the
box 14 being connected by a pipe 19 with the first heater o¹ whence the air is
conducted by a pipe 20 to the cock R¹ of the distribution apparatus described in
a previous Patent. In the present example the distributor (Figure 9) comprises
two cocks (or it may be slide or other valves) the first cock R1 controlling the
admission to the small cylinder while the second cock R controls the compound
or simple working. By means of this cock R, pipe 20 may be put in
communication through passage 21 with the open air or compressed air inay be
admitted directly to the small cylinder through pipe 22. Pipe 23 connects the
exhaust of the small cylinder to the distribution cock R' from which the pipe 24
is connected with the second heater o, whence the hot compressed air is conducted
by pipe 25 to the valve box of the large cylinder. The cock R2 will also admit the

page_text: air from heater of directly into the large cylinder for working at high pressure in
both cylinders, by placing pipe 24 in communication with 26 which is in connection
with 20 by means of the pressure regulator 27 (Figure 10). This regulator permits
the introduction into the small cylinder and expands of the large cylinder in working
direct. It consists of a piston valve I by which the pressure arriving by pipes 20
is admitted to chamber II. When the pressure therein has attained the
predetermined degree for supply to the engine the valve I is closed by the same
pressure exerted in the annular space III raising the cylinder IV and compressing
spring V through rod VI. When the pressure in chamber II falls, the spring V
opens the valve and allows air to pass until the pressure in chamber II balances
the spring V. The compressed air may be admitted direct from the reservoirs into the
small cylinder by means of a three-way cock VI without passing valve I.
working at high pressure in both cylinders the cock R2 connects the exhaust
pipe 23 of the small cylinder with the exhaust casing 7 (Figure 2) by the
passage 28.
For the proper working of the vehicle the driver has control of the reversing,
expansion, and distributing gear and the brakes. The forward or backward running
is controlled by a cock near each platform by means of which the compressed air is
admitted to the one or other side of a small piston 29 controlling the slide valve
reversing link 30. The speed of the vehicle is regulated by varying the cut off of
the Meyer Expansion Valve to the high pressure cylinder by turning the handing
wheel on shaft 31 (Figure 3) which turns the screwed rod 32 of the Meyer Expansion
Valve through the shafts. 33, 34, 35, and chain gear, each platform being provided
with similar handing gear and the shaft 34 being geared with one or other of the
shafts 33 according to the direction of running. The position of the distribution
cocks R¹ and R is controlled by similar arrangements from the handing wheels on.
shafts 36 either of which is geared with the shaft 37 through the shafts 38, 39, and
chain gear, the shaft 39 being geared with one or other of the shafts 38, the putting
of either set of handing gear into operative connection being effected by admitting
compressed air to the one or other end of a cylinder 40 whose piston rod is connected
to forked levers 41, 42, which engage with collars on shafts 34 and 39. The brakes
are operated by means of the pressure regulator 41 which is similar to that described
in a former Patent and is controlled by a lever 42 upon which act cams 43 and 44 on
the shaft which controls the air distribution, in such manner that the brakes can only
be applied after closing the admission to the engine cylinders. The running of the
vehicle is thus constantly under control and the speed can be increased or reduced to
any extent desired.
When, for instance, space is limited the distribution cocks may be replaced by slide
and other valves as represented in an elementary manner in Figure 11 wherein A' is
a vertical shaft operated from a handing shaft A on the driver's platform through an
endless chain. Upon shaft A¹ are keyed two toothed sectors S1, S2, and a cam K, all
the different adjustments being performed during a complete turn of shaft A'. The
sector S1 by which through the pinions p', p, p, p, p, the Meyer Expansion Valve
of the high pressure cylinder is adjusted, requires only half a turn to shift the
expansion valve from one extreme to the other, leaving two fourths of a revolution of
which one is required by the cam K to operate the brakes and the other by the
sector S for changing from compound to direct working as follows:-When on
shaft A being rotated in the direction of the arrow F1 the last tooth
of section S escapes from pinion P¹ the first tooth of sector S² engages
in pinion p. By still continuing to turn the shaft in the same direction,
the pinion will be rotated and the crank pin B' will describe a half-circle carrying
with it the slide valve T. In the position shewn the pipe C and consequently
space M behind the piston P is open to the air through port O. The slide valve T¹
will thus be held towards the right by the difference of pressure on the pistons P¹, P²,
of unequal area. This position corresponds to compound working, the exhaust from
small cylinder & passing by pipe E to the slide valve T and thence by pipe I'
through the re-heater o to the valve chest of the large cylinder l.
i

page_text: When slide valve T' is shifted by the sector S2 it first cuts off communication of
pipe C with the air, and then gradually uncovers the orifice of the pipe to allow
compressed air, admitted at C, to pass directly thereto and thence through pipe C
to the space M where, by reason of the difference of area of the pistons P1 and P2, the
effect of the pressure is to suddenly shift the slide valve T over to the left hand
position. In this position the pipe C communicates with I and the exhaust pipe E'
from the small cylinder communicates with E leading to the exhaust chainber
through which the small cylinder & exhausts to the open air, at same time that the
direct air pressure admitted by valve T¹ passes through I and re-heater o² to the
valve chest of the large cylinder 1. To each position of the slide valve T corresponds
a different area of admission to the large cylinder, the sides of the port over which
the slide valve is shifted being inclined relatively to one another so that the further
the sector S2 moves in the direction of the arrow F1 the greater the admission to the
large cylinder. In other words the driver, after having changed the working from
compound to direct, still has under control the admission to the large cylinder which
.he can vary at will. When the crank pin B¹ reaches the end of its course the
sector S meets a stop which limits the rotation of the handing shaft. By turning
the handing wheel shaft A, and consequently the shaft A', in the direction of the
arrow the opposite effects are produced, that is to say the crank pin B¹ returning
to the position shewn the valve Ti cuts off direct admission and opens C¹ to the air.
The valve T being no longer under the action of pressure within chamber M is
caused to suddenly assume the position shewn by reason of the difference of area of
the pistons P1, P2. When by the continued motion of the shaft A¹ in the direction
of the arrow F the sector St quits the pinion p the lugs which regulate the cut-off
are at their maximum distance apart so that the valve chest is closed against any
admission whatever either to the small or large cylinder. By still continuing to turn
in the direction of the arrow F the cam K acts on friction roller G of the lever L
and thus actuates the brake regulator 41 whereby pressure is admitted to the brake
cylinders gradually and under the control of the handing gear. It will thus be seen
that the whole of the mechanisin can be controlled by the one shaft A¹ since during
its passage from one extremne position to the other the following operations are
performed in succession.
By turning in the direction of the arrow F¹:-(1) The cam K quits the friction
roller G thus releasing the brakes; (2) The sector S' engages the pinion thus
gradually opening the admission to the small cylinder by acting on the lugs of the
expansion valve, the working being compound; (3) The admission to the small
cylinder being completely open, the sector S2 engages the pinion p whereupon the
working is suddenly changed to direct, and whilst the admission to the small cylinder
remains open that to the large cylinder is opened gradually. Complete control is
tbus obtained, it being understood that by turning the shaft in the opposite direction
the same effects are produced in the inverse order.
For greater safety and to enable a sudden stoppage in case the chain or other part.
of the banding gear should fail, a safety apparatus N is provided which is controlled
by a small cock R placed within reach of the driver whereby to enable the communi-
cation of the cylinders with the compressed air supply to be suddenly cut off. It
consists of a cylinder containing piston P on the stem of a valve held to its
seat C in the position shewn by pressure behind the piston P admitted by the
pipe C. The seat C is movable and also acts as a valve closing against a seat as
soon as the valve C quits it the parts being in the position shewn. The compressed
air from pipe C passes through pipes C5 and C to the two cylinders K and L. but by
turning the cock R through 45 degrees in the direction of the arrow the pipe C is
open to the air, the valves C5 and C are moved to the right, the former closing
against its seat and cutting off the supply of compressed air to the pipes C and C
the pressure remaining in these pipes pushing the piston 1" to the left and opening
valves C so that the compressed air still contained in pipes Cand C³ may escape past
the wings of the valve stem and through the pipe C which leads to the exhaust
chamber. Thus by turning cock R through 45 degrees in the direction of the arrow

page_text: both the cylinders are suddenly opened to the air and by turning it through
another 45 degrees the pipe Co remains open to the air, the pipe C₁o is connected
with C, and pressure is then admitted to the pipe to actuate the brakes which are
thereupon applied.
Date D.. 104L 1000
I, VICTOR POPP of 80. Rue Taitbout, Paris, France, 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 a compressed air locomotive carriage specially arranged
with a view to simplicity, compactness, and the utilization of compressed air in the
most efficient manner. The engine which is carried upon a single framing of special
construction, comprises two cylinders of different diameters for compound working
but capable of simple working when increased power is required, in which case the
system of distribution forming the subject of previous Letters Patent no 6128
of 1894 is employed. Reversing is effected by admitting compressed air to one or
other side of a small auxiliary piston which actuates the slide valves. The compressed
air is heated before it enters each of the cylinders, by means of small heaters having
a large surface heated by a separate furnace under forced draught of air injected
from the exhaust. The admission of compressed air is regulated so as to obtain any
desired speed of the driving pistons at all times, by means of a Meyer Expansion
Gear, in order that the compressed air may do its work in the most efficient inanner.
The compressed air reservoirs are charged at certain points of the journey by means
of the improved automatic feed apparatus forming the subject of a former Patent.
no 5726 of 1894.
Reference is to be had to the drawings accompanying the Provisional Specification
in which
Figure 1 represents a side elevation of the locomotive carriage.
Figure 2 is a plan of the engines with the body and floor of the car removed.
Figure 3 is a plan of the handing gear.
Figure 4 is a cross section on line 1-2 Figure 2.
Figure 5 is a side elevation of the framing which carries the engines.
Figure 6 is a vertical section of the air heater furnace.
Figure 7 is a vertical section of the air heater.
Figure 8 is a vertical section of the draught nozzle for the air heater furnace.
Figure 9 is a cross section of the distribution cocks.
Figure 10 is a vertical section and plan of a regulator placed in front of the
cylinders.
Figure 11 is a diagrammatic view shewing a modification of the compressed air
distribution to the various parts.
The same letters of reference denote like parts in all the Figures.
a is the frame of the under carriage carrying the engines and other parts of the
nechanism and is the frame carrying the body of the vehicle and the compressed
air reservoirs hung from the underside of the floor. By this arrangement the vibration
of the engines is not communicated to the carriage body and the wheel axles
may be brought closer together without affecting the stability of the car.
The springs of frame a are. very stiff so that this frame always remains nearly

page_text: horizontal while the points of support of frame b upon frame a being far apart greater
stability is obtained although the interposed springs are flexible. The axles inay
thus be brought so close together as to be able to run in curves of very small radius.
The engines are carried by a single frame c carrying the crosshead guides dd, one
end of the frame being supported by two bearings upon the axle e and the other upon
a spring (figures 4 and 5) on the frame a or directly upon said frame. Upon axle e
is keyed a toothed wheel g driven by a pinion g' keyed on the crank shaft & turning
in bearings i carried by frame c and having two cranks at 90° operated by the two
pistons. The speed of the engines with regard to the vehicle wheels therefore
depends upon the ratio of the gear y g which is enclosed in a dust-tight casing and
may run in a bath of oil. The cylinders klare of different diameters to admit of
compound working by the smaller cylinder exhausting into the larger cylinder.
When however extra power is required, or in case the small piston be at the dead
point at starting, the pressure may be admitted directly to both cylinders by a
special arrangement of cocks.
The compressed air is supplied to the reservoirs m through the inlet n by means of
the self-acting feed apparatus forming the subject of a previous Patent no 5726
of 1894 before referred to. The compressed air before admission to the cylinders is
heated by passing through the heaters o¹ o2 each consisting as shewn in Figure 7 of
a series of serpentine tubes & through which the air circulates, the tubes being fixed
in a casing p provided with baffles q through which circulate the products of com-
bustion from a furnace (figure 6). To accommodate as many tubes as possible
they are fixed as follows:-The tube ends are screw threaded and provided with
back nuts and cap nuts i having square holes v to receive a key for screwing up
the exps, tight joints being ensured by asbestos or other suitable packing. By this
mode of fixing the tubes may be placed very close together and a large heating
surface obtained in a sinall space. The inlet and outlet ¹ for the compressed air
have a sectional area equal to the aggregate internal sectional area of the tubes 8.
y is the inlet and y¹ the outlet for the heated gases from the furnace 7. On leaving
the second heater the gases are conducted to an apparatus hereinafter described for
promoting the draught. The heating furnace shewn in Figure 6 is enclosed and
fed automatically from a closed container 7 of a size to work for one day without re-
charging. The ash-pan 1 has openings 2 regulated by dampers 3 controlled by a
lever 4 and links 5 to regulate the admission of air for combustion. A double inclined
deflector 6 is provided to deflect the air upwards to the bars in whichever direction
the car is travelling. The furnace gases after having traversed each of the heaters
are expelled by means of a forced draught produced by the exhaust air from the
engines for which purpose the exhaust from each of the cylinders after being
expanded down in a chamber 7 (Figure 2) is conducted through a pipe 8 (Figure 8)
and blast nozzle 9 into a pipe y2 which receives the furnace gases, the area of the
nozzle being regulated by the cone 11 adjustable by the knob 10. The gases are
thus discharged continuously into the atmosphere since the exhaust air is also
continually escaping owing to its expansion in the chamber thus preventing shocks
and reducing the velocity of the escaping air. When the engines are not working, a
draught is obtained by a jet of compressed air supplied through the passage 12 to the
annular nozzle 13 around the nozzle 9. The supply of compressed air is effected
automatically; the air on entering the receiving inlet n is admitted by lifting the
check valve in the box 14 (Figure 2) which communicates with reservoirs m by pipes 15
and 16 and the flexible pipes attached to their ends 17 and 18. The compressed
air on leaving the reservoirs m passes to the heaters, the box 14 being connected by
a pipe 19 with the first heater o' whence the air is conducted by a pipe 20 to the
cock R¹ of the distribution apparatus described in a previous Patent before referred
In the present example the distributor (Figure 9) comprises two cocks (or it
may be slide or other valves) the first cock R controlling the admission to the small
cylinder while the second cock R³ controls the compound or simple working. By
means of this cock R¹ pipe 20 may be put in communication through passage 21 with
the open air or compressed air may be admitted directly to the small cylinder through

page_text: pipe 22. Pipe 23 connects the exhaust of the small cylinder to the distribution
cock R2 from which the pipe 24 is connected with the second heater of whence the
hot compressed nir is conducted by pipe 25 to the valve box of the large cylinder.
The cock R will also admit the air from heater o' directly into the large cylinder for
working at high pressure in both cylinders by placing pipe 24 in communication
with 26 which is in connection with 20 by means of the pressure regulator 27
(Figure 10). This regulator permits the introduction into the small cylinder and
expands the air of the large cylinder in working direct. It consists of a piston valve I
by which the pressure arriving by pipe 20 is admitted to chamber 11. When the
pressure therein has attained the predetermined degree for supply to the engine the
valve I is closed by the same pressure exerted in the annular space III raising
the piston IV and compressing spring V through rod VI. When the pressure in
chainber II falls, the spring V opens the valve and allows air to pass until the pressure
in chamber II balances the spring V. The compressed air may be admitted direct
from the reservoirs into the small cylinder by means of a three-way cock VII without
passing valve I. When working at high pressure in both cylinders the cock R
(fig. 9) connects the exhaust pipe 23 of the small cylinder with the exhaust casing 7
(Figure 2) by the passage 28.7
For the proper working of the vehicle the driver has control of the reversing,
expansion, and distributing gear and the brakes. The forward or backward running
is controlled by a cock near each platform by means of which the compressed air is
admitted to the one or other side of a small piston 29 (figure 1) controlling the
slide valve reversing link 30. The speed of the vehicle is regulated by varying the
cat-off of the Meyer Expansion. Valve to the high pressure cylinder hy turning
the handing wheel on shaft 31 (Figures 1 and 3) which turns the screwed rod 32 of the
Meyer Expansion Valve through the shafts 33,, 34, 35, and chain gear, each platform
being provided with similar handing gear and the shaft 34 being genred with one or
other of the shafts 33 according to the direction of running. The position of the
distribution cocks R and R2 is controlled by similar arrangements from the handing
wheels on shafts 36 (fig 3) either of which is geared with the shaft 37 through the
shafts 38, 39, and chain gear, the shaft 39 being geared with one or other of the
shafts 38, the putting of either set of handing gear into operative connection being
effected by admitting compressed air to the one or other end of a cylinder 40 whose
piston rod is connected to forked levers 41, 42, which engage with collars on shafts 34
and 39: The brakes are operated by means of the pressure regulator 41 which is
similar to that described in a former Patent no 6128 of 1894 hefore referred to and is
controlled by a lever 42 upon which act cams 43 and 44 on the shaft which controls
the air distribution, in such manner that the brakes can only be applied after closing
the admission to the engine cylinders. The running of the vehicle is thus constantly
under control and the speed can be increased or reduced to any extent desired.
When for instance space is limited the distribution cocks may be replaced by slide
and other valves as represented in an elementary manner in Figure 11 wherein A¹ is
a vertical shaft operated from a handing shaft A2 on the driver's platform
through an endless chain. Upon shaft A are keyed two toothed sectors S¹ S
and a cam K, all the different adjustinents being performed during a complete
turn of shaft A¹. The sector S₁ by which through the pinions p¹ p² p
pp the Meyer Expansion Valve of the high pressure cylinder k is adjusted,
requires only half a turn to shift the expansion valve from one extreme to the
other, leaving two fourths of a revolution of which one is required by the
cam K to operate the brakes and the other by the sector St for changing
from compound to direct working as follows:-When on shaft. A being rotated in
the direction of the arrow F¹ the last tooth of sector S¹ escapes from pinion p¹ the
first tooth of sector S2 engages in pinion p. By still continuing to turn the shaft
in the same direction the pinion p will be rotated and the crank pin Bi will describe
a half-circle carrying with it the slide valve T. In the position shewn the pipe C
and consequently space M' behind the piston P' is open to the air through port O.
The slide valve T will thus be held towards the right by the difference of pressure

page_text: on the pistons P P of unequal area. This position corresponds to compound
working, the exhaust from small cylinder & passing by pipe E' to the slide valve T
and thence by pipe through the re-heater o to the valve chest of the large
cylinder l.
When slide valve T' is shifted by the sector S* it first cuts off communication of
pipe C with the air, and then gradually uncovers the orifice of the pipe to allow
compressed air, admitted at 03 to pass directly thereto and thence through pipe C
to the space M' where by reason of the difference of area of the pistons P' and P' the
effect of the pressure is to suddenly shift the slide valve T2 over to the left hand
position. In this position the pipe C cominunicates with I' and the exhaust
pipe E from the small cylinder communietes with E leading to the exhaust
chamber through which the small cylinder k exhausts to the open air, at same time
that the direct air pressure admitted by valve T passes through I and re-heater o to
the valve chest of the large cylinder . To each position of the slide valve T
corresponds a different area of admission to the large cylinder, the sides of the port
over which the slide valve is shifted being inclined relatively to one another so that
the further the sector S2 moves in the direction of the arrow F¹ the greater the
admission to the large cylinder. In other words the driver, after having changed
the working from compound to simple, still has under control the admission to
the large cylinder which he can vary at will.. When the crank pin B, reaches the
end of its course the sector S¹ meets a stop which limits the rotation of
the handing shaft. By turning the handing wheel shaft A2 and consequently the
shaft A' in the direction of the arrow F2 the opposite effects are produced, that is to
say the crank pin B' returning to the position shewn the valve T cuts off direct
admission and opens C to the air. The valve T being no longer under the action
of pressure within chamber M' is caused to suddenly assume the position shewn by
reason of the difference of area of the pistons P1 P2. When by the continued motion
of the shaft A' in the direction of the arrow F the sector S¹ quits the pinion p' the
lugs which regulate the cut-off are at their maximum distance apart so that the valve
chest is closed against any admission whatever either to the small or large cylinder.
By still continuing to turn in the direction of the arrow F the cam K acts on
friction roller G of the lever L and thus actaates the brake regulator 41 whereby
pressure is admitted to the brake cylinders gradually and under the control of the
handing gear. It will thus be seen that the whole of the mechanism can he
controlled by the one shaft. A since during its passage from one extreme position to
the other the following operations are performed in snccession.
By turning in the direction of the arrow F1-(1) The cam K quits the friction
roller G thus releasing the brakes; (2) The sector S1 engages the pinion pl thus
gradually opening the admission to the small cylinder by acting on the lugs of the
expansion valve, the working being compound; (3) The admission to the small
cylinder being completely open the sector S2 engages the pinion p whereupon the
compound working is suddenly changed to simple working and whilst the admission
to the small cylinder remains open that to the large cylinder is opened gradually.
Complete control is then obtained, it being understood that by turning the shaft in
the opposite direction the same effects are produced in the inverse order.
For greater safety and to enable a sudden stoppage in case the chain or other part
of the handing gear should fail, a safety apparatus N is provided which is controlled
by a small cock R placed within reach of the driver whereby to enable the com-
munication of the cylinders with the compressed air supply to be suddenly cut off. It
consists of a cylinder containing a piston P3 on the stem of a valve C held to its
seat C in the position shewn by pressure behind the piston Pa admitted by the
pipe C. The seat C³ is movable and also acts as a valve closing against a seat as
soon as the valve C quits it. The parts being in the position shewn, the compressed
air from pipe C passes through pipes C and C to the two cylinders & and l but by
turning the cock R through 45° in the direction of the arrow the pipe C is open to
the air, the valves C and C are moved to the right, the former closing against its
seat and cutting off the supply of compressed air to the pipes C3 and C, the pressure

page_text: remaining in these pipes pushing the piston P3 to the right and opening valve C so
that the compressed air still contained in pipes C5 and C³ may escape past the wings
of the valve stem and through the pipe C which leads to the exhaust chamber. Thus
by turning cock R through 45° in the direction of the arrow both the cylinders are
suddenly opened to the air and by turning it through another 45° the pipe C
remains open to the air the pipe C10 is connected with C and pressure is then
admitted to the pipe to actuate the brakes which are thereupon applied.
Having now particularly described and ascertained the nature of the said.
Invention and in what manner the same is to be performed I declare that what
I claim is :-
1. The herein described locomotive carriage driven by compressed air or other gas,
comprising the combination of the following special arrangements :-
(a) the mode of driving the axle, comprising the use of a single frame connected
at one end to the axle by two bearings and resting at the other on the vehicle frame
either directly or through a spring, this frame carrying the crank shaft driven by two
cylinders, the shaft and wheel axle being geared together by spur gear enclosed in a
casing;
(b) the mode of suspension, comprising the use of two distinct frames, the one
carrying the gearing and the other the vehicle body;
(c) the re-heater, comprising a series of tubes heated by a special furnace, the
draught of which is obtained by the blast of exhaust air without the use of a
chimney;
(d) two cylinders of different diameters adapted for working compound or at the
same pressure in hoth cylinders;
(e) the mode of adjusting the reversing links by means of compressed air.
2. In the system of compressed air locomotive herein specified, the ineans of con-
trolling the working whereby a single shaft is adapted to control the brakes, the
cut-off to the high pressure cylinder, the change from compound to simple working,
and the progressive admission of high pressure to the large cylinder, as specified in
reference to Figure 11.
3. In the system of controlling gear herein specified, the safety device set in action
by a cock under the control of the driver whereby to suddenly cut-off the connection
of the compressed air supply with the engine cylinders and consisting of a piston and
double valve working in a barrel having two chambers with which the air pipes are
connected substantially as specified.
Dated the 7th day of August 1897.
A. M. & WM. CLARK.
Chartered Patent Agents. 53. Chancery Lane. London.