IMPROVEMENTS IN LOCOMOTIVES FOR LDATAVO AND LIGHT RAILWAYS
Year: 1880

page_text: LETTERS PATENT to Henry Percy Holt, of No. 15, Park Row, Leeds, in the
County of York, and Francis William Crossley, of Manchester, in the County
of Lancaster, for an Invention of "IMPROVEMENTS IN LOCOMOTIVES FOR
LDATAVO AND LIGHT RAILWAYS"
PROVISIONAL SPECIFICATION left by the said Henry Percy Holt and
Francis William Crossley at the Office of the Commissioners of Patents on
the 23rd August 1880.
HENRY PERCY HOLT, of No. 15, Park Row, Leeds, in the County of York,
and FRANCIS WILLIAM CROSSLEY, of Manchester, in the County of Lancaster.
"IMPROVEMENTS IN LOCOMOTIVES FOR TRAMWAYS AND LIGHT RAILWAYS."
Our Invention relates to locomotives for tramways and light railways, so
constructed and arranged that they can be readily stopped, reversed, and turned
round without stoppage or reversal of the engines which work them. For this
purpose we mount the vehicle on four running wheels, two before and two behind,
with a pair of intermediate driving wheels on an axle worked by gearing from the
engine shaft.
This axle is mounted in bearings in radial arms, which can be swung
when desired into different positions, so that the driving wheels, while the gearing
which works them remains engaged, can be moved either forwards and downwards
so as to bear on the road or rails and drive the vehicle in one direction, or back-
wards and upwards so as to be off the road or rails but to bear against the peripheries
of a pair of the running wheels and drive them by frictional contact, thus reversing
the direction of travel of the vehicle; or the driving wheels may be held in an
intermediate position, bearing neither on the road or rails, nor on any of the running
wheels, and so having no propulsive effect on the vehicle. Instead of swinging the
driving axle as above described either or both of the running axles may be
similarly swung on radial arms or links, while the bearings of the driving axle are
fixed. In this case either one or both ends of the engine framing may be lifted by
swinging either one or both pairs of the running wheels to a position in which the
radial arms above mentioned are vertical, or nearly so, the driving wheels being
thus raised along with the framing so as to run clear of the road or rail; or either
Price 10 271

page_text: pair of the running wheels may be farther swung so as to be brought into contact
with the driving wheels when they are thus elevated, and so to be driven by
frictional contact in the reverse direction, thereby reversing the movement of the
vehicle. Instead of mounting the moveable axles upon radial arms, as above
described, their bearings may obviously be fitted to move in curved or inclined
guides for the same purpose. In any case the desired movement of the axle may
be obtained by screw or other gearing, worked by hand, or by the engine, or
preferably by hydraulic power.
In order to provide for the varying load upon the running wheels we arrange
duplicate springs to bear on each of their axle boxes. One of these springs is
comparatively light to act when the load on the running wheels is moderate, but
when that load is increased beyond a certain amount the bearing comes upon the
heavier of the two springs in addition to the lighter spring.
For the purpose of turning the vehicle round we fix near the middle of it a
vertical hydraulic cylinder, having a plunger extending downwards and terminating
in a four armed crosshead, which is usually held a little above the surface of the
road or rails. By forcing liquid under pressure into the hydraulic cylinder the
plunger is depressed until its crosshead bears upon the road or rails and the vehicle
and its wheels are raised. The vehicle is then turned round the plunger as an
axis, and when it is lowered by relieving the hydraulic pressure, and the plunger
and crosshead are raised, the vehicle can run in its reversed attitude and direction.
The hydraulic cylinder with its plunger and crosshead may be dispensed with by
adopting the following arrangement-We divide one of the running axles so that
its two wheels can revolve independently of each other, and at the opposite end of
the vehicle we provide a transverse wheel on a longitudinal axle which can be
raised or lowered and clutched so as to be driven by suitable gearing from the
engine shaft. When it is desired to turn the vehicle this wheel is lowered down
to the ground and subjected to pressure sufficient to lift the driving wheels and
one pair of the running wheels off the road, so that the vehicle is entirely supported
on the two independent running wheels and on the transverse wheel, which being
driven causes the vehicle to turn round, after which the transverse wheel can be
uncoupled and raised so that the vehicle is again borne on its driving and running
wheels. In turning the vehicle in this manner the two independent wheels on
which it partly rests necessarily leave the rails. In order to ensure their return to
the rails when the vehicle is reversed we lower through a hole in the floor of the
vebicle immediately over the centre line of their axles a bolt, which entering a
socket provided in the ground operates as a perch pin, round which the vehicle
turns.
We provide a maximum speed brake, which is worked under the control of a
governor by pressure from the engine cylinder in the following manner :- -When
the speed tends to become excessive the governor opens a valve which admits
the working fluid to a cylinder to act on a piston connected to the brakes, so
that the brakes are put on. And when on the other hand the speed becomes
reduced the governor opens an escape valve from this cylinder so as to release the
brakes. The passage to the brake cylinder is provided with a check valve to
prevent return of fluid at the times when the pressure in the working cylinder is
reduced. Practically, we find that by means of a small hole or slight looseness of
fit of the brake piston there is sufficient escape of the fluid pressing on it, when no
fresh supply is received from the working cylinder, to permit the brakes to be taken
off by the weight or spring usually applied for that purpose.
For the purpose of clutching or unclutching either or both of the driving wheels
or the gearing that works them, so that their respective speeds may be varied,
or either or both may be stopped by unclutching them or their gearing, we employ
a friction clutch arranged as follows:-The wheel to be driven is mounted loose on
the shaft that has to drive it, and a drum attached to it is surrounded by a friction
band made in halves and jointed together on a pivot or crank pin revolving with
the driving shaft. The ends of the friction band are pressed together by springs

page_text: so that they clamp the drum between them, and while they do so the drum is
caused to revolve along with the shaft. For the purpose of unclamping them a
lever pivotted on an arm of the driving shaft has two short arms linked respectively
to the ends of the two halves of the friction band, and has a third long arm
connected to a chain which passes over a guide. pulley, and is led to a small
barrel central with the driving shaft but loose therein. On this barrel is fixed
a small friction drum surrounded by a friction band which can be tightened or
slackened by a hand lever. As long as this band remains slack, the barrel is
free to revolve with the shaft, and, consequently, the lever permits the halves of the
friction band to clamp the drum in obedience to the springs. When, however, by
tightening the small friction strap the barrel is retarded, the chain becomes partly
wound on it, and the lever is thus pulled upon so that the halves of the friction
band are opened apart thereby unclutching the drum. A pawl may be applied to
hold in the lever, in which case the friction on the small drum can be relieved.
By loading the long arm of the lever the springs may be dispensed with, the
centrifugal force of a weight on the lever acting instead of the springs so as to
clamp the halves of the friction band on the drum, unless when the lever is pulled
in by the retardation of the small barrel as above described.
As at
The improvements above set forth are particularly applicable to locomotives in
which a gas motor engine is employed, this engine being worked by gas stored in a
reservoir carried by the locomotive. As it is necessary to charge this reservoir from
time to time, it is of advantage to do so at a fixed station which is most con-
veniently the terminal point of the line on which the locomotive travels.
such a point the locomotive has to be reversed, we there provide means for
simultaneously raising it off the ground, turning it round, and charging its reservoir.
For this purpose we provide at the terminus a stop for the vehicle, which may be
a depression in the rails, in such a position that a hollow cone at or near the centre
of gravity of the vehicle is immediately above a cone ended plunger or ram
arranged in the ground below, so that it can be raised by hydraulic pressure or by
gearing. On raising this ram the vehicle is raised off the road and is turned round
on the rain as a pivot, and on again lowering the ram the vehicle takes its bearings
on the road or rails in a reversed position, ready to make its return journey. By
making the rain tubular and connecting it to a gas supply pipe, and by forming a
passage from the hollow cone of the vehicle to its gas reservoir; the reservoir can be
charged with gas at the time when the vehicle is being raised, turned, and lowered.
It is of advantage to provide in the hollow cone and in the cone of the ram self-
closing valves, which open for passage of gas only when the one is seated firmly on
the other. When the arrangement for lifting and turning the vehicle by a ram
working in the ground is adopted, the arrangements previously mentioned for this
purpose may be dispensed with.
The arrangement above described may obviously be inverted, the ram or plunger
being depressed from the vehicle into a socket provided in the road, so that the
wheels of the vehicle can be thus raised off the road, and the vebicle can be turned
round while it is being supplied with gas through its ram or plunger. Also the
raising of the vehicle may be dispensed with by running it on to a turn-table,
having in its centre the passage for gas supply to the reservoir of the vehicle.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Percy Holt and Francis William Crossley in the Great Seal
Patent Office on the 22nd February 1881.
HENRY PERCY HOLT, of No. 15, Park Row, Leeds, in the County of York,
and FRANCIS WILLIAM CROSSLEY, of Manchester, in the County of Lancaster.
"IMPROVEMENTS IN LOCOMOTIVES FOR TRAMWAYS AND LIGHT RAILWAYS."
Our Invention relates to locomotives for tramways and light railways, so
constructed and arranged that they can be readily stopped, reversed, and turned
round without stoppage or reversal of the engines which work them. For this
purpose we mount the vehicle on four running wheels, two before and two behind,
with a pair of intermediate driving wheels on an axle worked by gearing from the
engine shaft. This axle is mounted in bearings in radial arms, which can be
swung when desired into different positions so that the driving wheels, while the
gearing which works them remains engaged, can be moved either forwards and
downwards so as to bear on the road or rails and drive the vehicle in one direction,
or backwards and upwards so as to be off the road or rails, but to bear against the
peripheries of a pair of the running wheels and drive them by frictional contact,
thus reversing the direction of travel of the vehicle; or the driving wheels may be
held in an intermediate position, bearing neither on the road or rails nor on any
of the running wheels, and so having no propulsive effect on the vehicle. Instead
of swinging the driving axle as above described, either or both of the running
axles may be similarly swung on radial arms or links while the bearings of the
driving axle are fixed. In this case either one or both ends of the engine framing
may be lifted by swinging either one or both pairs of the running wheels to a
position in which the radial arms above mentioned are vertical or nearly so, the
driving wheels being thus raised along with the framing so as to run clear of the
road or rail. Or either pair of the running wheels may be farther swung, so as to
be brought into contact with the driving wheels when they are thus elevated, and
so to be driven by frictional contact in the reverse direction, thereby reversing the
movement of the vehicle. Instead of mounting the moveable axles upon radial
arms as above described their bearings may obviously be fitted to move in curved
or inclined guides for the same purpose. In any case the desired movement of the
axle may be obtained by screw or other gearing worked by hand or by the engine
or preferably by hydraulic power.
In order to provide for the varying load upon the running wheels we arrange
duplicate springs to bear on each of their axle boxes. One of these springs is
comparatively light to act when the load on the running wheels is moderate, but
when that load is increased beyond a certain amount the bearing comes upon the
heavier of the two springs in addition to the lighter spring.
For the purpose of turning the vehicle round we fix near the middle of it a
vertical hydraulic cylinder having a plunger extending downwards and terminating
in a four-armed crosshead which is usually held a little above the surface of
the road or rails. By forcing liquid under pressure into the hydraulic cylinder the
plunger is depressed until its crosshead bears upon the road or rails, and the
vehicle and its wheels are raised. The vehicle is then turned round the plunger
as an axis, and when it is lowered by relieving the hydraulic pressure and the
plunger and crosshead are raised the vehicle can run in its reversed attitude and
direction. The hydraulic cylinder with its plunger and crosshead may be dispensed
with by adopting the following arrangement-We divide one of the running
axles so that its two wheels can revolve independently of each other, and at the
opposite end of the vehicle we provide a transverse wheel on a longitudinal axle,

page_text: which can be raised or lowered and clutched so as to be driven by suitable gearing
from the engine shaft. When it is desired to turn the vehicle this wheel is lowered
down to the ground and subjected to pressure sufficient to lift the driving wheels
and one pair of the running wheels off the road, so that the vehicle is entirely
supported on the two independent running wheels and on the transverse wheel,
which, being driven, causes the vehicle to turn round, after which the transverse
wheel can be uncoupled and raised so that the vehicle is again borne on its
driving and running wheels. In turning the vehicle in this manner the two
independent wheels on which it partly rests necessarily leave the rails. In order
to ensure their return to the rails when the vehicle is reversed we lower through a
hole in the floor of the vehicle immediately over the centre line of their axles a
bolt, which, entering a socket provided in the ground, operates as a perch pin,
round which the vehicle turns.
We provide a maximum speed brake, which is worked under the control of a
governor by pressure from the engine cylinder in the following manner:- -When
the speed tends to become excessive the governor opens a valve which admits the
working fluid to a cylinder to act on a piston connected to the brakes, so that the
brakes are put on. And when, on the other hand, the speed becomes reduced
the governor opens an escape valve from this cylinder so as to release the brakes.
The passage to the brake cylinder is provided with a check valve to prevent
return of fluid at the times when the pressure in the working cylinder is reduced.
Practically we find that by means of a small hole or slight looseness of fit of the
brake piston there is sufficient escape of the fluid pressing on it when no fresh
supply is received from the working cylinder to permit the brakes to be taken off
by the weight or spring usually applied for that purpose.
For the purpose of clutching or unclutching either or both of the driving wheels
or the gearing that works them so that their respective speeds may be varied, or
either or both may be stopped by unclutching them on their gearing, we employ a
friction clutch arranged as follows:-The wheel to be driven is mounted loose on
the shaft that has to drive it, and a drum attached to it is surrounded by a friction
band made in halves and jointed together on a pivot or crank revolving with the
driving shaft. The ends of the friction band are pressed together by springs, so
that they clamp the drum between them, and while they do so the drum is caused
to revolve along with the shaft. For the purpose of unclamping them a lever
pivotted on an arm of the driving shaft has two short arms linked respectively to
the ends of the two halves of the friction band, and has a third long arm
connected to a chain which passes over a guide pulley, and is led to a small
barrel central with the driving shaft, but loose thereon. On this barrel is fixed
a small friction drum surrounded by a friction band, which can be tightened
or slackened by a hand lever. As long as this band remains slack the barrel
is free to revolve with the shaft, and consequently the lever permits the
halves of the friction band to clamp the drum in obedience to the springs. When
however by tightening the small friction strap the barrel is retarded, the chain
becomes partly wound on it, and the lever is thus pulled upon, so that the halves
of the friction band are opened apart, thereby unclutching the drum.
A pawl may
be applied to hold in the lever, in which case the friction on the small drum can
be relieved. By loading the long arm of the lever the springs may be dispensed
with, the centrifugal force of a weight on the lever acting instead of the springs so
as to clamp the halves of the friction band on the drum unless when the lever is
pulled in by the retardation of the small barrel as above described.
The improvements above set forth are particularly applicable to locomotives in
which a gas motor engine is employed, this engine being worked by gas stored in
a reservoir carried by the locomotive. As it is necessary to charge this reservoir
from time to time, it is of advantage to do so at a fixed station, which is most
conveniently the terminal point of the line on which the locomotive travels. As
at such a point the locomotive has to be reversed we there provide means for
simultaneously raising it off the ground, turning it round, and charging its

page_text: reservoir. For this purpose we provide at the terminus a stop for the vehicle,
which may be a depression in the rails, in such a position that a hollow cone at or
near the centre of gravity of the vehicle is immediately above a cone ended
plunger or ram arranged in the ground below, so that it can be raised by hydraulic
pressure or by gearing. On raising this ram the vehicle is raised off the road and
is turned round on the ram as a pivot, and on again lowering the ram the vehicle
takes its bearings on the road or rails in a reversed position ready to make its
return journey. By making the ram tubular and connecting it to a gas supply
pipe, and by forming a passage from the hollow cone of the vehicle to its gas
reservoir, the reservoir can be charged with gas at the time when the vehicle is
being raised, turned, and lowered. It is of advantage to provide in the hollow
cone and in the cone of the ram self-closing valves, which open for passage of gas
only when the one is seated firmly on the other. When the arrangement for
lifting and turning the vehicle by a ram working in the ground is adopted, the
arrangements previously mentioned for this purpose may be dispensed with.
The arrangement above described may obviously be inverted, the ram or plunger
being depressed from the vehicle into a socket provided in the road, so that the
wheels of the vehicle can be thus raised off the road, and the vehicle can be turned
round while it is being supplied with gas through its ram or plunger; also the
raising of the vehicle may be dispensed with by running it on to a turntable,
having in its centre the passage for gas supply to the reservoir of the vehicle.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a longitudinal section, and Fig. 2, a plan of a gas motor locomotive
according to our Invention; Fig. 3 is a transverse section at the engine shaft, and
Fig. 4 is a transverse section behind the hinder running wheels. A is the cylinder
of the gas motor engine, the piston of which works the beam B, from which by
means of a connecting rod motion is given to a crank on the shaft C. This shaft
carries fly wheels C¹ and pinions C2 which work the driving wheels D, causing
them to revolve always in one direction. There are two pairs of running wheels,
the hind wheels E and the front wheels E. The axles of both these sets of wheels
having their bearings fitted in vertical guides, cach provided with two sets of
springs, an inner spring e and a stronger external spring e' which butts against a
stop plate e, so that when the load exceeds a certain amount, causing the bearings
to press against the stop plates e², both springs are brought into action upon them.
The axle bearings of the hinder wheels E are mounted in frames F which are secured
together by tie bolts f, and are fitted to turn on studs G projecting from the
framing. The plunger of a hydraulic cylinder H is connected by links H' to the
frames F, so that when the plunger is forced forwards by the pressure of water
admitted to the cylinder H, the frames F are caused to turn partly about the axis
of the studs G, bringing the wheels E forwards to a position where their axle is
more nearly vertically under the studs G. This has the effect of raising the body
of the locomotive and lifting its wheels D off the road or rails, so that they cease
to act as driving wheels. If the wheels E be drawn still farther forwards by the
action of the plunger of H, they are brought in contact with the wheels D and are
driven by frictional contact with them, so that they become driving wheels,
propelling the vehicle in the opposite direction. Each of the wheels E and E¹ has
a brake block e³, each pair of which is connected by a cross bar e' for the the hind
brakes, and e for the front brakes. On turning the spindle e by a handle e a
chain es is wound on the spindle. This chain passes round a pulley e and is attached
to a lever e¹0 which is linked to the crossbar e³. The pulley e is connected by a
rod el to an arm on a cross shaft G' which has shorter arms linked to the cross
bar e¹. Thus when the chain is wound on the spindle e both sets of brakes, those
for the hind wheels E and those for the front wheels E¹, are simultaneously pressed
against their respective wheels. On releasing the chain the brakes are taken off
by springs. For the purpose of raising the vehicle off the ground and turning it

page_text: round we employ the crosshead I at the lower end of a vertical shaft I, which is
fitted to work in a socket I attached to the framing of the vehicle.
At the upper
end of this socket is a hydraulic cylinder J having its piston J attached to the
shaft I, which works through packing in the cylinder bottom. When the annular
area on the underside of the piston J' is subjected to pressure whilst the upper
side of the piston is relieved from pressure the crosshead I is raised, as shewn in
Fig. 1; but when the pressure is allowed to act on the greater area on the upper
side of the piston the crosshead I is depressed, and after it comes to bear on the
ground the vehicle is bodily raised off the ground, and can be turned round the
shaft I. For providing the hydraulic pressure to act in the cylinders H. and J we
place a force pump at K worked by an arm on the shaft of the reciprocating
beam B, connecting this pump by a suction pipe to a cistern K¹, and by a
discharge pipe to a valve box . We provide the pump K with relief
apparatus K³, consisting of a cylinder containing a piston or plunger pressed in one
direction by an adjustable spring and in the opposite direction by the discharge
water of the pump K. This piston or plunger is connected to the suction valve of
the pump, so that when the pressure of the discharge of the pump exceeds a fixed.
limit the suction valve is held open and the action of the pump thereupon ceases.
The valve box 2 communicates with the cylinder H, and by a return pipe ³ with
the cistern K. A hand lever K is connected by a rod K5 to a differential lever Kº,
the opposite end of which is linked to one of the rods H', the lever near its middle
being connected to a slide valve in the valve box ². On pushing back the hand
lever K the slide valve in 2 is moved so as to admit pressure to act in the
cylinder H, causing its plunger and the rods H¹ to move forwards.
As they
advance they close the slide in and thereby become arrested in their motion,
taking thus a position corresponding with that to which the hand lever K* has
been moved. The position of the hind wheels E is thus determined by that of the
hand lever K. For working the crosshead I a cock or valve J2 communicates by
branch pipes with the cylinder J, the pipe ¹, and the cistern K¹. By moving this
cock or valve the piston J¹ is subjected to pressure on its upper side or relieved
therefrom. The underside of the piston J' is always subject to the hydraulic
pressure, the bottom of the cylinder J communicating for that purpose by a branch
pipe with the pipe k. In order to govern the speed of the vehicle, so that it shall
not exceed a certain limit, we employ the following arrangement:-On the engine
cylinder we fix a valve box L, a section of which is shewn to an enlarged scale at
Fig. 5. It contains two valves, both seating over a lower compartment L', but
placed in two separate upper compartments, one of which, L², communicates with
the engine cylinder, and the other, L³, communicates with a cylinder M. A two
armed lever is fixed on a spindle L which is worked like the spindle of a throttle
valve by a governor in the usual way, this governor being driven from the front
running axle. Should the speed of the vehicle become excessive the governor by
partly turning the spindle L lifts the valve in the compartment L2 and admits the
working fluid of the engine under pressure to the compartment L', whence it passes
the valve in L³ and proceeds to act in the cylinder M pushing out its plunger. This
plunger is connected by a lever M' to the chain es, so that the protrusion of the
plunger causes the brakes to be put on. When the speed of the vehicle becomes
reduced below its inferior limit the spindle L is turned by the governor in the
opposite direction, so that the valve in L³ is lifted and the fluid under pressure can
return from the cylinder A back to the cylinder of the engine, the valve in L²
acting then as a check valve and thus the brakes are released. In what precedes
we have described the raising of the vehicle and the reversal of its movement as
being effected by advancing the hinder running wheels. The effect of this is
illustrated diagrammatically in Fig. 6, in which are shewn the various positions
which the engine shaft C with its gearing C2 and driving wheels D can be made to
assume by the advancing of the hinder wheels E. Instead of moving these wheels
the driving wheels D moved, as indicated in Fig. 7, so as either to be on
or off the road or rails or to be brought in contact with the front running wheels E¹.

page_text: The movement of the wheels D for this purpose may be effected, as shewn, by a
crank or eccentric D linked to swinging frames which carry the bearings of the
driving axle D¹. When this arrangement is adopted the crank or eccentric D² is
made of such throw that it is on its dead centre for either extreme position of the
driving axle. The vehicle may be raised parallel to the road by adopting the
arrangement shewn diagrammatically in Fig. 8. In this case two cross shafts D³
and D mounted on the framing of the vehicle have cranks D and D, which are
jointed to an underframing carrying the axles of the wheels E and E', so that by
turning simultaneously more or less the shafts D and D' the vehicle with its
driving axle D' and wheels D can be raised and advanced, as indicated by the
dotted lines.
Fig. 9 is a longitudinal section; Fig. 10 is a transverse section; Fig. 11 is an
end view, and Fig. 12 is a plan of an arrangement of gas motor locomotive, in
which the raising and turning round is effected by means of a transverse end
wheel N. When the vehicle comes to a part of its course where it has to be
turned, a pin is dropped into a socket O provided on the ground and surrounded
by a circular rail O¹. The axle of the front running wheels E¹ is divided, or either
or both of these wheels is fitted loosely on it, so that they can turn independently of
each other. On depressing the cross wheel N by means of a screw the back end
of the vehicle along with the driving and hind running wheels is raised, and the
vehicle can thereupon be turned round the socket O as on a perch-pin, the front
wheels E' running on the circular rail O'. When this arrangement is adopted
the stoppage of the driving wheels while the engine shaft continues to revolve is
effected by means of clutch gear, such as we will now describe. Fig. 13 is a vertical
transverse section through the engine shaft, and Fig. 14 is a side elevation of the
clutch gear; C is the engine shaft; C' the fly wheel, and C the pinion which drives
the driving wheel D. This pinion is loose on the engine shaft but is attached to a
brake wheel P, which is embraced by two semicircular brake bands P¹ and P² that
are jointed together at P³ on a stud projecting from an arm of the fly wheel C¹.
The ends of the bands P¹ and P2 are respectively linked to opposite arms of a short
lever or sway beam P, and they are pressed together by springs P³. The spindle
of the lever P* has fixed on it a lever arm P, which is attached by a chain to a
barrel P. This barrel is free to revolve on a stud at the end of the engine shaft,
and it has on it a brake wheel Ps embraced by a flexible brake strap, which can
be tightened by means of a bell crank lever Pº. As long as this brake strap
remains loose, the barrel P' being free to revolve with the engine shaft, the chain
is left slack and the springs P³ press the bands P¹ and P against the brake
wheel P, which, along with the pinion C³, in that case revolves along with the
engine shaft. By tightening the strap on P³, the revolution of the barrel P7 is
retarded, and the chain becoming wound upon it partly turns the spindle P, and
thereby presses the bands P' and P2 apart, thus releasing the brake wheel P and
pinion C, which may then remain at rest while the engine shaft continues to
revolve, the driving wheels D being thus retarded or arrested. In some cases.it
is advisable to be able to change the ratio of the driving gear; for this purpose we
use the clutch arrangement, as shewn in Figs. 10 and 12, the power being transinitted
through either set of gear, as may be required. For the purpose of turning the
vehicle round, and at the same time charging its reservoir with gas at its terminus,
we provide the arrangement shewn in longitudinal section at Fig. 15, and in
transverse section at Fig. 16, and by the perspective plan of the road, Fig. 17;
Qis a tube which can be raised or lowered by a rack or pinion worked by hand
or by hydraulic or other convenient power. The lower end of this tube works
through a stuffing box into a stand pipe or vessel Q¹, which communicates with
the gas main Q2, and which contains water or other liquid up to a certain level.
The upper end of the tube Q is coned to fit a socket Q³, fixed to the framing of the
vehicle, and communicating with the gas reservoir R by a pipe R¹, which is
provided with a check valve R². When the tube Q is lowered, its lower end, being
immersed in the liquid in Q', is sealed against passage of gas. When the vehicle

page_text: arrives at its terminus, its socket Q3 being immediately above the tube Q, this tube
is raised till its coned end becomes firmly seated in the socket, in which position it
opens the valve R2 by pressing up its stem. The tube Q being farther raised till its
lower end emerges from the liquid in Q', the vehicle is raised bodily and can be
turned round as a perch pin, gas at the same time passing from the main Q²
to the reservoir R. The vehicle having been turned the tube Q is lowered again,
becoming sealed against passage of gas, and the valve R2 seats itself preventing
escape of gas from the reservoir R. It is often of advantage to provide a double
set of the lifting and charging apparatus at the terminus, as shewn at Fig. 17, in
which one of the tubes Q is shewn projecting above the road level, the other
tube Qbeing supposed to be lowered. In cases where a supply of gas is not
required, may be a a solid stem for raising and turning the vehicle; and the
tube or stem Q instead of being protruded upwards from the ground may be
protruded down from the vehicle into a socket in the ground by an arrangement
like that described with reference to Figs. 1, 2, and 3; the crosshead I shewn in
these Figures being in that case dispensed with, and the stem of the piston J'
having its lower end fitted to turn in the socket. When sufficient power to lift
the vehicle cannot conveniently be obtained, a turntable may be provided on which
the vehicle can be turned, the gas supply tube being protruded through the centre
of the turntable so as to charge the reservoir as described.
Having thus described the nature of our Invention and in what manner the
same is to be performed, we claim in respect of locomotives for tramways and light
railways,
First. Mounting one or more of the axles so that they can be moved relatively
to the vehicle, thus raising the driving wheels off the road or rails, or bringing
them in contact with some of the running wheels, thereby controlling the speed or
effecting reversal of the motion of the vehicle while the driving wheels continue
to revolve in one direction, substantially as herein described.
Second. Utilising the pressure of the working fluid of the engine for working
the brakes under control of a speed governor, substantially as herein described.
Third. Raising the vehicle for the purpose of turning it by means of a vertically
moving stem or tube which operates at the same time as a lift and a pivot,
substantially as herein described.
Fourth. Supplying gas to a gas motor locomotive by means of a tube round
which as a pivot the vehicle is turned, substantially as herein described.
Fifth. The construction of gas motor locomotive, substantially as herein
described with reference to Figs. 1, 2, 3 and 4 of the accompanying Drawings.
Sixth. The combination of the valve arrangement L, Fig. 5, worked by a
governor, the cylinder and its plunger M, and lever M¹ with the brake gear,
substantially as and for the purpose herein set forth.
Seventh. The construction and arrangement of locomotive wherein the turning
of the vehicle is effected by the use of a tranverse end wheel in combination with a
perch pin or circular rail, substantially as herein described with reference to
Figs. 9, 10, 11 and 12.
Eighth. The construction of clutch substantially as herein described with
reference to Figs. 13 and 14.
Ninth. The construction and arrangement of lifting pivot and gas supply,
substantially as described with reference to Figs. 15, 16, and 17.
In witness whereof, I, the said Henry Percy Holt, have hereunto set my
hand and seal, this Nineteenth day of February, in the year of our Lord One
thousand eight hundred and eighty one.
HENRY PERCY HOLT. (L.S.)