IMPROVEMENTS IN TRACTION ENGINES FOR TRAM, RAIL, OR OTHER ROADS
Year: 1883

page_text: LETTERS PATENT to William Wilkinson, of Wigan, in the County of Lancaster,
Mechanical Engineer for an Invention of "IMPROVEMENTS IN TRACTION
ENGINES FOR TRAM, RAIL, OR OTHER ROADS
"3
PROVISIONAL SPECIFICATION left by the said William Wilkinson at the
Office of the Commissioners of Patents on the 31st March 1883.
WILLIAM WILKINSON of Wigan, in the County of Lancaster, Mechanical Engineer
"IMPROVEMENTS IN TRACTION ENGINES FOR TRAM, RAIL, OR OTHER ROADS
My invention relatos to certain improvements in Boilers and Blast pipe arrange-
ments, Governors, and Geared driving connections, applicable to traction engines in
general, but more particularly to the type of engine patented to me 1 Oct 1881
No 4268
My said improvements are designed to prevent the emission of visible steam or
sparks from the funnel: and to reduce the noise of the exhaust; to provide an
automatic governor to control the speed of the engine and actuate the breaks and
reversing gear; and to provide a geared driving connection which shall admit of
freedom of movement or side cant to the carrying wheels, without risk of fracture
of the wheel teeth.
To carry into effect the first named object, viz:-freedom from the emission of
visible steam or sparks and the reduction of noise from the exhaust, I employ two
alternative devices.
In the first of these the exhaust is led into receivers to intercept any condensa-
tion water from the cylinders, and to serve as expansion chambers. These are
placed in any suitable position on or about the boiler where they shall be warm.
Thence the steam is led into a superheating chainber, suspended in the furnace at a
convenient distance below the uptake. The noise of the exhaust is thus dendened.
Above the superheating chamber I place a series of concentric rings of any suitable
cross section, but preferably oval. These rings are each connected by a pipe with
the superheating chamber, and are perforated on their upper sides to allow the
superheated steam to escape in a number of jets. They are arranged in a pyramidal
*Price 021

page_text: form, each ring being so much less in external diameter as to leave the perforations
of the ring immediately below it free, to allow of the issue of the steam jet without
obstruction.
Through the centre of the annular chamber I fix a vertical pipe for the proper
regulation of the draught. The annular chamber thus formed is fixed in any
convenient part of the uptake, the superheated steam is distributed thereby, and it
serves as a heat baffle and spark arrestor.
In my alternative device, from the superheating chamber springs an outlet or
escape pipe, inside which and carried through the chamber to the furnace is a
second or blast pipe of smaller diameter, coned if desired at its lower end, so as to
present an enlarged orifice over the centre of the furnace, the orifice being fitted
with a removeable grid or perforated plate of suitable material. Between the two
pipes is left an annular space for the escape from the superheating chamber, and
the two pipes are proportioned so that this space shall meet the requirements of
the cylinders. In the centre and near the top of the blast pipe is a nozzle to project
a steam jet upwards, and around but apart from the top outer circumference of the
outer pipe, is a ring of perforated pipe, to project a ring of steam jets upwards
Both the nozzle and the ring are fed by a pipe in. direct communication with the
boiler, and also with main steam pipe between the boiler regulator valve and the
steam cylinder, or with each separately if preferred, and is fitted with a cock to
regulate or cut off the supply from one or both at pleasure. The funnel imme-
diately above the delivery of the blast is internally jacketed with an air tight
annular space, so that the influence of the outer atmosphere is minimized. The
strong induced draught from the hottest part of the furnace caused by my jet
arrangement mixes with the exhaust and jet steam, and causes the same to be still
more heated, absorbed, and dried, and thus delivered from the funnel in an invisible
and distributed condition. The grid over the furnace serves as a spark arrestor,
and I further construct one or more of the inner rings of "Field " tubes imme-
diately and concentrically surrounding the superheating chamber below the tube
plate, of an enlarged or bottle-like section, so that their walls may be close enough
together to arrest sparks of any consequence, whilst not unduly interfering with the
draught.
The safely valve is enclosed in a box communicating with the receivers common
to my preceding alternative methods, and any steam therefrom is carried along
with the steam from the exhaust.
To effect the second named of my objects, viz:-to provide a governor which
shall automatically control the speed of the engine, and actuate the breaks and
reversing gear, I construct my governor as follows:-
My governor is of the ordinary high speed, centrifugal, knuckle-jointed type
(known as a Porter governor) with the centrifugal weights acting by means of a
sleeve sliding on the spindle against a spiral spring or counterpoise. The spindle
is driven from any convenient axle of the engine, and a projection formed on the
moving sleeve, engages if raised by increased speed, with a nut on the spindle of a
steam valve, which being thereby lifted admits steam. A second nut is provided
on the valve spindle, with which the projection engages when the sleeve falls on
stoppage of the engine, and the valve is thereby closed. The spindle is screw-
threaded, so as to admit of the nuts being moved to suit any desired speed. The
steam is led to the two brake cylinders and two reversing gear cylinders through a
two-way cock or valve, situated opposite a prolongation of the governor spindle,
which delivers to either sot, according to the direction in which the engine is
running. The lever of the cock or valve is connected to a sleeve on a round nut
free to travel on a screw-thread on the prolongation of the governor spindle. As
the governor spindle revolves in one or other direction, the nut, sleeve, and valve
lever, travel to one or other end of the prolongation, and the steam is delivered
through the valve to the proper brake cylinders and reversing gear. Stop collars
are fitted at each end of this prolongation, and they and the flanges of the travelling,
nut are conveniently formed so as to engage with one another.
4.

page_text: To carry into effect the third named object, viz:-to provide a geared driving
connection which shall admit of freedom of movement or side cant to the carrying
wheels without risk of fracture :--
I construct toothed gearing of particular form, to commuuicate the driving strain
from a cranked driving shaft running in fixed bearings, to a carrying wheel shaft
running in spring pressed bearings, the gearing being situated at the centre of the
Baid shafts.
The faces or bearing surfaces of the teeth of each of the toothed wheels, are
curved longitudinally to the axis so that they bear chiefly at their centres. This
particular construction of tooth, together with the central position of least oscilla-
tion of the gearing, allows of considerable side cant of the axle, and freedom of
action, without the liability to fracture resulting from cross winding of the teeth.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Wilkinson in the Great Seal Patent Office on the
28th September 1883.
WILLIAM WILKINSON, of Wigan, in the County of Lancaster, Mechanical Engineer,
"IMPROVEMENTS IN TRACTION ENGINES FOR TRAM, RAIL, OR OTHER ROADS
"
My invention relates to certain improvements in boilers and blast pipe arrange-
ments, governors, and geared driving connections, applicable to traction engines in
general, but more particularly to the type of engine patented to me 1 October 1881.
Number 4268.
My said improvements are designed to prevent the emission of visible steam or
sparks from the funnel and to reduce the noise of the exhaust; to provide an
automatic governor to control the speed of the engine and actuate the breaks and
reversing gear; and to provide a geared driving connection which shall admit of
freedom of movement or side cant to the carrying wheels, without risk of fracture
of the wheel teeth.
In order that my invention may be the better understood, I now proceed to describe
the same with reference to the accompanying drawings and to the letters and
figures marked thereupon. Like letters refer to like parts throughout the figures.
Figure 1. is a side elevation of my improved engine.
Figure 2. is a section through the boiler showing steam drying and quieting and
spark arresting devices.
Figure 3. is an enlarged detail of a portion of Figure 2.
Figure 4. is a section of boiler showing alternative devices to effect the first
named objects.
Figure 5. is my improved governor
Figure 6. is a plan of the driving connections.
Figure 7. is an enlarged detail of the wheel teeth.
To carry into effect the first named objects, viz:-freedom from the emission of
visible steam or sparks and the reduction of noise from the exhaust, I employ two
alternative devices :-
In the first of these, Figure 1, the exhaust is led into receivers E, to intercept
any condensation water from the cylinders, and to serve as expansion chambers.
These are placed in any suitable position (though conveniently as shown) on or
about the boiler F where they shall be warm. Thence the steam is led by suitable
pipes into a superheating chamber H, suspended in the furnace at a convenient
distance below the uptake. The noise of the exhaust is thus deadened. Above
the superheating chamber H I place a series of concentric rings W of any suitable
cross-section, but preferably oval. These rings are shown enlarged in Figure 3.
The rings have each a pipe springing from a duct leading from the superheating
chamber H, and are perforated on their upper sides to allow the superheated steam
to escape in a number of jets. They are arranged in a pyramidal form, each ring
being so much less in external diameter as to leave the perforations of the ring
immediately below it free to allow of the issue of the steam jet without obstruction.
Through the centre of the annular chamber thus formed, I fix a vertical pipe w,
Figure 3, for the escape of a portion of the exhaust steam for the proper regulation
of the draught. The annular chamber thus formed W is fixed in any convenient
part of the uptake P Figure 2; the superheated steam is distributed thereby so as
to issue invisibly and at the same time it serves as a heat baffle and spark
arrestor.
In my alternative device Figure 4, from the superheating chamber H springs an
annular outlet or exhaust pipe, the interior tube of which forms a heat funnel,

page_text: coned if desired at its lower end n' which passes through the chamber H, so as to
present an enlarged orifice over the centre of the furnace. The orifice is fitted with
removable grid or perforated plate h of suitable material to withstand the heat and
which shall serve to arrest the passage of cinders or sparks.
The annular space between this funnel and the outer exhaust pipe is proportioned
to meet the requirements of the exhaust steam escaping from the cylinders. In
the centre and near the top of the heat funnel n¹ of the exhaust pipe is a nozzle L
to project a steam jet upwards, and around but apart from the top outer
circumference of the exhaust pipe, is a ring of perforated pipe, to project a ring
of steam jets upwards. Both the nozzle and the ring are fed by a pipe in direct
communication with the boiler, from which they may be supplied with steam when
required, but they are also connected with the main steam pipe, between the boiler
regulator valve and the steain cylinder, an automatic feed of steam being thus
obtained whenever the steam supply is turned on to the engines by the driver.
The steam pipes to the jets are provided with stop cocks so that either supply can
be cut off when desired, the automatic feed from the engine steam pipe being
preferred in ordinary use, as it ceases when the engine is at rest, and is turned on
necessarily with the the steam supply to the engine, just at the time when the jets
are required i. e. when the exhaust commences to pass up the chimney and should
be invisible.
The funnel immediately above the delivery of the blast is internally jacketed
with an air tight annular space g g, so that the cooling influence of the outer
atmosphere is minimized.
The strong draught induced from the hottest part of the furnace by my jet
arrangement mixes with the exhaust and jet steam, and causes the same to be still
more heated, absorbed, and dried, and thus delivered from the funnel in an invisible
and distributed condition.
The issue of sparks or cinders is arrested at the bottom of the blast funnel by
the grid h, and at the uptake one or more rings of the "Field" tubes V,
immediately and concentrically surrounding the superheating chamber H, are made
of an enlarged or bottle shape as shown, so that they may be close enough together
to prevent the passage of sparks or cinders of any consequence whilst not unduly
interfering with the draught.
All the waste steam from the cylinder exhaust or cocks or from the safety
valve T enclosed in a box for the purpose, is passed through the receivers E and
superheating chamber H and is disseminated invisibly as hereinbefore described.
To effect the second named of my objects, viz:-to provide a governor which
shall automatically control the speed of the engine, and actuate the break and
reversing gear I construct my apparatus as shown in Figure 5. The governor ✗
is of the ordinary high speed, centrifugal, knuckle-jointed type, (known as a
"Porter" Governor) with the centrifugal weights acting by means of a sleeve K
sliding on the spindle against a spiral spring k or counterpoise. The spindle is
driven from any convenient axle of the engine and a projection formed on the
moving sleeve K, engages, if raised by increased speed, with a nut u on the screwed
spindle of the steam valve U which being thereby lifted allows the steam from the
boiler to pass through the pipe. A second nut u is provided on the valve spindle
with which the projection engages when the sleeve K falls on stoppage of the
engine, and the closing of the valve U is thereby ensured, if it should not have
closed by its own weight. The nuts u u¹ may be adjusted to any position on the
screwed valve spindle so as to suit any desired speed.
The steam, allowed to pass the valve U by the before described action of the
governor is led to the two sets of brake cylinders and reversing gear cylinders,
(one being for forward and the other for back gear), through a two-way cock or
valve Y situated opposite to a prolongation of the governor spindle. This cock or
valve delivers the steam to either set of brake and reversing cylinders, through
the alternative pipes y or y! according to the direction in which the engine is

page_text: running. The lever of the cock or valve is connected to a sleeve on a round
nut Z free to travel on a screw-threaded prolongation of the governor spindle.
The governor reverses its direction of rotation with the reversing of the move-
ment of the engine. As the governor revolves in one or the other direction, so the
nut Z, the sleeve and valve lever, travel to one or the other end of the screw thread.
The cock or valve Y is thus adjusted so as to be open to the proper brake and
reversing cylinders and closed towards the other set, ready for the action of the
steam when the latter is allowed to pass the valve V by the rising of the governor
sleeve K. Stop collars z z¹ are fitted at each end of the screw thread, and they
and the flanges of the travelling nut Z are formed with projections to engage into
one another, so as to check the travel of the nut Z before it jams against either
collar.
To carry into effect the third named object viz:-to provide a geared driving
connection which shall admit of freedom of movement or side cant to the axle of
the carrying wheels on the driving shaft, without risk of fracture of the driving
gearing, I construct my apparatus as shown in Figures 6 and 7.
My driving geared wheels C and D, gearing from the engine crank shaft B, which
lies in fixed bearings, to the carrying axle S, which runs in spring pressed bearings,
are placed in the centre of the said shafts
The faces or bearing surfaces of the teeth of each of the toothed wheels, whether:
they are plain cog teeth, stepped teeth, or diagonal teeth, are curved longitudinally
to the axis so that they bear chiefly at their centres. This is shown in detail in
Figure 7. This particular construction of tooth together with the central position of
the gearing at the point of least oscillation, allows of considerable side cant to the
axle, and consequent freedom of movement in the spring pressed axle boxes, without
the liability to fracture resulting from the crosswinding of the teeth.
Having now described and ascertained the nature and objects of my invention,
and the manner of carrying the same effect, be it known that what I consider novel
and desire to protect by Letters Patent is :-
First. In traction engines for tram-car or other purposes, the combination with
receivers and a settling tank, external to the boiler, and a superheating vessel in
the fire-box; of a pyramidal series of perforated escape pipes therefrom, in the
funnel, to superheat, distributo, and render invisible, the waste steam from the
engines, and act as a spark arrestor, substantially as described.
Second. In traction engines for tram-car or other purposes, the alternative 3
combination with receivers and settling tank, external to the boiler, and a super-
heating vessel in the fire-box, of an annular steam escape pipe in the uptake,
surrounded inside and out by the hot gases from the furnace, passing through an
interior optionally coned funnel, and the exterior air-jacketed up-take, substantially
as and for the purposes described.
Third. In traction engines for tram-car or other purposes, the combination
with the annular escape pipe as in claim 2, of a live steam internal jet and external
perforated ring jet, about the mouth of the said escape pipo, and in alternative
communication with the boiler and engine steam pipe, substantially as and for the
purposes described.
Fourth. In traction engines for tram-car or other purposes, the construction of a
high speed "Porter" or other governor with a tappet on the rising and falling
sleeve, operating a valve, and a reversing nut operating a two way cock, to effect
by a steam or hydraulic apparatus, in either forward or back gear, the automatic
breaking and reversal of the engines, by undue increase of speed, substantially as
described.
Fifth. In traction engines for tram-cars. or other purposes, the construction of
the boiler with one or more concentric rows of Field Tubes, surrounding the uptake,
enlarged in diameter below their necks, so as to closely approximate to each other
to arrest the passage of cinders or sparks, substantially as described.
Sixth. In traction engines for tram-cars or other purposes the construction of
5

page_text: geared wheels upon the centres of the fixed crank shaft and spring pressed driving
axle respectively, the teeth of which, whether plain, stepped, or diagonal, are
rounded on their bearing faces across the wheels, so as to allow the free cross
winding of the spring-pressed axle relatively to the crank shaft, substantially as
described.
Seventh. In traction engines for tram-cars or other purposes the combination of
all or any of the preceding subordinate claims to form a noiseless and efficient
public road engine, substantially as described.
In witness whereof I, the said William Wilkinson, have hereunto set my
hand and seal this twenty-sixth day of September in the year of our Lord
One thousand eight hundred and eighty-three.
W WILKINSON (L.S.)
W WILKINSON (L.S.)