IMPROVEMENTS IN LOCOMOTIVES FOR TRAMWAYS 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
TRAMWAYS AND LIGHT RAILWAYS."
PROVISIONAL SPECIFICATION left by the said Henry Percy Holt and
Francis William Crossloy at the Office of the Commissioners of Patents on
the 27th March 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 the construction and arrangement of locomotives
applicable on tramways and light railways, our principal object being to provide
ready means of starting, stopping, or reversing the direction of movement, and of
varying the driving power. For this purpose we provide a truck, which may be
of bogie construction, and on this truck we mount the engine and the bearings for
the driving axle, fixing them on a framing which is capable of being raised or
lowered, and of being turned round a vertical axis relatively to the truck body
or frame. By this means we are enabled to raise the driving wheels out of contact
with the rails, and to turn the driving axle half round to an inverted attitude, so
that while it continues to revolve in the same direction relatively to the engine the
wheels upon it when they are again brought in contact with the rails propel tho
vehicle in the direction opposite to that in which they propelled it before inversion
of the axle. The engine framing may be raised and lowered either by hydraulic
pressure produced by a pump worked by the engine, or by a screw or screws
reversible in direction by clutch gearing; or the framing may be supported on
springs sufficient to raise it, fluid or other mechanical pressure under control of the
driver being applied to force the framing down in opposition to the springs. By
the raising or lowering of the driving wheels their frictional hold on the rails is
varied so as to give less or greater propelling power, as required. For the running
wheels of the vehicle we provide breaks, which are preferably arranged so as to bo
pressed by springs against the wheels, hydraulic or other power being applied to

page_text: take off the breaks. In some cases we connect these breaks to the engine framing,
so that they are put on or taken off according as the framing is raised or lowered.
When the vehicle has a car body or platform with a boiler, air or gas reservoir, or
other store of power, a foot plate or accommodation for a driver, conductor, or
passengers, the whole of these may be turned with the engine framing, the
vehicle being thus reversed relatively to its truck or under framing and running
wheels without the reversal of the truck itself, for which an external turntable or
its equivalent would be required. The engine may work one or more pairs of
driving wheels, all of which would partake of the raising, lowering, and turning
movement above described. When hydraulic pressure is employed for raising or
lowering the framing or working the breaks, the pump for this purpose may be
provided with an adjustable lever, the length of which is varied by a plunger
subject to the pressure produced, which pressure is under the control of the driver,
so that the pump is caused, to force a greater or less quantity of liquid according
as a greater or less quantity is required. Also a governor may be applied to
regulate the hydraulic power independently of the driver so as to diminish or
increase the contact pressure of the driving wheels, and increase or diminish the
pressure of the break blocks on the running wheels, according as the speed of the
vehicle is too high or too low. Sometimes when the axle has been turned to
the attitude suitable for running in one direction, it is convenient to be enabled
to run a short distance in the opposite direction without inverting the axle ; as for
example, for the purpose of backing in order to couple a car. To provide for this
we mount a pair of idle wheels nearly in contact with the driving wheels, and so
arranged that they can be brought into contact with them and with the rails, so
that while the driving wheels revolve out of contact with the rails these idlo
wheels are driven by them, and for the time operate as driving wheels, propelling
the vehicle in a direction opposite to that in which the driving wheels would propel
it. Or according to another arrangement we provide on one of the revolving axles
a winch barrel or grooved pulley to wind up a rope attached to the stationary car,
and so to effect the backing of the locomotive vehicle. In some cases instead of
lifting the whole engine and parts connected with it, we raiso or lower only the driving
axle or axles, the connections for working them being then arranged so as to
allow for their elevation and depression.

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 25th September 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 the construction and arrangement of locomotives
applicable on tramways and light railways, our principal object being to provide
ready means of starting, stopping, or reversing the direction of movement, and of
varying the driving power. For this purpose we provide a truck, which may be
of bogic construction, and on this truck we mount the engine and the bearings for
the driving axle, fixing them on a framing which is capable of being raised or
lowered, and of being turned round a vertical axis relatively to the truck body or
frame. By this means we are enabled to raise the driving wheels out of contact
with the rails, and to turn the driving axle half round to an inverted attitude, so
that while it continues to revolve in the same direction relatively to the engine,
the whools upon it, when they are again brought in contact with the rails, propel
the vehicle in the direction opposite to that in which they propelled it before
inversion of the axle. The engine framing may be raised and lowered either by
hydraulic pressure produced by a pump worked by the engine, or by a screw or
screws reversible in direction by clutch gearing; or the framing may be supported
on springs sufficient to raise it, fluid or other mechanical pressure under control of
the driver being applied to force the framing down in opposition to the springs.
By the raising or lowering of the driving wheels their frictional hold on the rails
is varied, so as to give less or greater propelling power as required. For the
running wheels of the vehicle we provide breaks, which are preferably arranged so
as to be pressed by springs against the wheels, hydraulic or other power being
applied to take off the breaks. In some cases we connect these breaks to the
engine framing, so that they are put on or taken off according as the framing is
raised or lowered. When the vehicle has a car body or platform with a boiler, air
or gas reservoir, or other store of power, a foot plate or accomodation for a driver,
conductor, or passengers, the whole of these may be turned with the engine
framing, the vehicle being thus reversed relatively to its truck or under framing
and running wheels without the reversal of the truck itself, for which an external
turn table or its equivalent would be required. The engine may work one or
more pairs of driving wheels, all of which would partake of the raising, lowering,
and turning movement above described. When hydraulic pressure is employed
for raising or lowering the framing or working the breaks the pump for this
purpose may be provided with an adjustable lover, the length of which is varied
by a plunger subject to the pressure produced, which pressure is under the control
of the driver, so that the pump is caused to force a greater or less quantity of
liquid, according as a greater or less quantity is required; also a governor may be
applied to regulate the hydraulic power independently of the driver, so as to
diminish or increase the contact pressure of the driving wheels, and increase or
diminish the pressure of the break blocks on the running wheels, according as the
speed of the vehicle is too high or too low. Sometimes when the axle has been
turned to the attitude suitable for running in one direction it is convenient to be
enabled to run a short distance in the opposito direction without inverting the
axle, as, for example, for the purpose of backing in order to couple a car. To
provide for this we mount a pair of idle wheels nearly in contact with the driving
wheels, and so arranged that they can be brought into contact with them, and
with the rails, so that while the driving wheels revolve out of contact with the
rails these idle wheels are driven by them, and for the time operate as driving.

page_text: wheels, propelling the vehicle in a direction opposito to that in which the driving
wheels would propel it. Or according to another arrangement we provido on one
of the revolving axles a winch barrel or grooved pulley to wind up a rope attached
to the stationary car, and so to effect the backing of the locomotive vehicle. In
some cases instead of lifting the whole engine and parts connected with it we raiso
or lower only the driving axlo or axles, the connections for working them being
then arranged so as to allow for their elevation and depression.
DESCRIPTION OF THE DRAWINGS.
In Sheet 1 of the accompanying Drawings Fig. 1 is a plan, Fig. 2 a longitudinal
section, Fig. 3 is a transverse section of one cosntruction of locomotive according to
our Invention, and Fig. 4 is a plan of the underframing and running wheels. bis
the horizontal engine shaft, which by means of toothed gearing o, o, works the
driving axle c. The body a of the vehicle which carrios the bearings of the shaft b
and horn plates for the bearings of the driving axle c is firmly attached to a
sheath which is fitted to revolve and slide on a vertical column t; this column
projects upward from a base plate secured to the underframing a' which rests upon
the running wheels and axles d. The sheath t' has at its upper end a hydraulic
cylinder, the piston of which is attached to the column t; and l³ are connections
for pressure pipes, which may be of the usual kind. The sheath that its base bears
on a number of buffer springs i, i, sufficiently powerful to lift the sheath and its
attachments, unless when it is pressd down by hydraulic pressuro admitted to act
under the piston ; when that pressure is relieved, and when pressure is admitted
to act above the piston l, the sheath with its attachments is raised sufficiently high
to enable the body of the vehicle and the running axle to be turned half round, the
driving wheels e¹ in that case passing clear over the underframing a¹. It is sometimes
of advantage to be able to move the vehicle backwards a short distance without
inverting the position of the driving axle, as, for example, when the vehicle has to
bo backed to couple to a car. To provide for this wo mount a lover arm v' on a
fixed eccentric v embracing the driving axle c at each end thereof, and on this lever
arm we mount a roller . The arms varo drawn upwards against stops by
springs, and in that position the rollers v aro clear of the peripheries of the
driving wheels. By means of chains v' worked by a winch barrel v³ the arms v¹
can be drawn down to a vertical attitude, bringing the rollers v³ under the driving
wheels c', in which position they act as intermediates between those wheels and the
road or rail, thus reversing the direction of propulsion.
The running wheels may have brakes of any known kind applied to them, such
as shewn in Sheet I., which aro worked in the following manner :-The brake
blocks * are fixed at the ends of cross bars u³, which are pressed by springs u²,
these springs, when they are not counteracted, forcing the brake blocks against the
wheels. For the purpose of taking off the brakes the plunger of a hydraulic cylinder u
is advanced against the upper end of either of two levers u', the lower end of which
is linked to that of the other by a connecting rod u; both levers are mounted on
bars attached to the springs u. Thus when the hydraulic plunger presses the one
lever u' towards the centre of the vehicle the spring and brake blocks to which it
is connected are forced back, and at the same time the other lever u' is acted on
in the same manner through the medium of the rod u³ which connects the two levers.
One of the running axles is free to move radially, its bearings being connected by radius
bars u to a central perch pin, and to allow for the radial motion the cross bar u³ of the
brakes is curved in the middle to fit the curved end of the bar which the spring u³
pushes against it. Guide cheeks m serve to hold the body of the vehicle in position
after it has been raised, turned half round, and lowered again. The raising and lowering
of the body of the vehicle with the running axle instead of being effected by hydraulic
pressure, as described, may be effected by screw gearing, as in the arrangement
shewn in Sheet II., where Fig. 5 is a longitudinal section of the locomotive;
Fig. 6 is a transverse section; Fig. 7, a plan; and Fig. 8, a plan of the under-

page_text: framing. In this case the sheath t¹ has mounted in it a worm wheel, which forms
a nut working on a screw fixed to the top of the column t, so that according as
the wheel t³ is turned in the one direction or the other the sheath t¹, along with the
body of the vehicle and its attachments, is raised or lowered. For the purpose
of turning this wheel it is geared with a worm t' on a cross shaft t which carries
at its outer end a friction wheel 15. This friction wheel is introduced into an
annular groove in the fly wheel, and its shaft is capable of rocking a little up or
down, so that the wheel t can be made to bear against either the inner or the
outer periphery of the annular groove, and thereby be caused to revolve in the one
direction or the other, while the fly wheel itself continues revolving always in
the same direction. The rocking movement is given to the shaft of the friction
wheel by means of a lever (which is connected by a rod t to a hand
lever . By means of this lever the attendant can move the friction wheel
upwards or downwards so as to raise or lower the body of the vehicle. It is
however advantageous to provido a spring t¹, which when the hand lever 10 is left
free will raise the friction wheel to and so cause the elevation of the vehicle body
except when the attendant moves his lever in opposition to the spring. The
sheath & carries a lever which is acted on by tappots on the column t so as to
disengage the friction wheel when the vehicle body is raised or lowered to its
full extent. It is of advantage to suspend the sheath t¹ by a spring W sufficient
to sustain a largo portion of the weight, so as to reduce the strain on the nut t
during the first portion of the upward movement, whereby the driving wheels are
taken off the road or rails, this being the movement which is most frequently
performed in the act of stopping and starting the vehicle.
In order to provide regulation of the speed of the vehicle a centrifugal governor
may be applied to the running axles, and this governor may act on the hand
lever to or its connections, so that when the speed exceeds a certain limit theo
driving wheels are automatically raised and brakes are applied to the running
wheels. The brake blocks u are fixed on the cross bars u³ which are pressed by
volute springs u². The bars u³ are connected by rods to the opposite vertical arms
of three armed levers u¹, the horizontal arms of which extend below the bottom of
the sheath t, so that whon the sheath is in its lowest position it presses down
these arms and thereby keeps the brakes off the wheels, but when the sheath is
raised a certain distance the volute springs u² cause the brake blocks to be pressed
against the wheels.
Our Invention may be applied as above described to a vohicle having a single
driving axle and a pair of driving wheels. It may also be applied to a vehicle
having two driving axles and two pairs of driving wheels, as shewn diagrammatically
in Sheet III., Fig. 9 being an end view, and Fig. 10 a side view of an arrangement
for this purpose, the two driving axles being indicated at c, c, and their driving
wheels at c¹, c. In this case the engine shaft b may either by cranks and con-
necting rods, as shown, or by suitablo gearing drive one of the axles c, which in its
turn may by cranks and side rods drive the other. The body of the vehicle, with
the engine and driving axles, is, as already described, attached to the sheath t¹,
which is fitted to slide up and down and to revolve round a central column.
We have mentioned abovo that our Invention is particularly applicable in cases
where the combustion of gas or inflammable vapours furnishes the motive power.
Gas for this purpose may be stored in sufficient quantity for a certain length of
journey in a reservoir provided on the roof of the vehicle, as indicated at G, in
Figs. 6, 9, and 10.
Having thus described the nature of our Invention, and in what manner the
same is to be performed, we claim,-
First. In locomotives for tramways and light railways, mounting the engine, the
bearings for the driving axle or axles, and the body of the vehicle on a vertical
column supported on the framing of a truck, so that the parts thus mounted can be
raised, lowered, or turned round on the column as an axis, substantially as and for
the purposes herein set forth.

page_text: Second. In locomotives arranged in the manner referred to in the preceding
claim, releasing the spring brakes of the running truck wheels by the weight of the
body of the vehicle when it is lowered, substantially as herein described with
reference to Figs. 5, 6, 7, and 8.
Third. In locomotives arranged in the manner referred to in the first claim,
providing a pair of idle wheels which, when the driving wheels are raised, can be
moved into such a position, as to make contact with the said wheels and with the
road or rail, thereby reversing the direction of motion of the vehicle, whilst that of
the driving wheels remains unchanged, substantially as herein described with
reference to Figs. 1, 2, and 3.
Fourth. The construction and arrangement of locomotive for light railways or
train ways, the engine and body of which are raised by bydraulic power, herein
described with reference to Figs. 1, 2, 3, and 4.
Fifth. The construction and arrangement of locomotive for light railways or
tramways, the engine and body of which are raised by screw gearing aided by
springs, herein described with reference to Figs. 5, 6, 7, and 8.
Sixth. The construction and arrangement of locomotive for light railways or
tramways, having four coupled driving wheels, herein described with reference to
Figs, 9 and 10.
In witness whereof, I, the said Henry Percy Holt, have hereunto set my
hand and seal, this Twenty second day of September, in the year of our
Lord One thousand cight hundred and eighty.
TIENDY DEDAY HOLT ral