Improvements in Tramway Locomotives.
Year: 1889

page_text: Date of Application, 3rd Apr., 1889
Complete Specification Left, 2nd Jan., 1890-Accepted, 29th Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements in Tramway Locomotives.
I, WILLIAM ROBERT ROWAN of Behrenstrasse 54, Berlin in the Empire of Germany,
Engineer, do hereby declare the nature of this invention to be as follows:-
Usually the crank shaft of a tramway locomotive engine has to revolve at con-
siderable speed and has to work the driving axle at a reduced speed by toothed or
friction gear. As the car or bogie which carries the engine is mounted on springs, it
has an up and down motion relatively to the driving axle, and this seriously interferes
with the action of the gearing by which this axle is worked.
To provide against this defect I, according to my invention, fix the engine cylinders,
piston rod guides and crank shaft bearings on a frame which at its one end, has
bushes embracing the driving axle, and at its other end is pivotted to the body of
the car.
This frame consequently oscillates with the car, but, as it works on the driving axle
as a centre, there is no variation in the radial position of the crank axle relatively to
the driving axle, and consequently the engagement of the gearing remains constant.
The horn plates for the boxes of the driving axle may be curved to a circular arc
struck from the pivot of the frame as a centre, or if the horn plates are, as usual
straight, this pivot is arranged in a sliding bearing which allows a little to and fro
longitudinal motion. The boiler which I employ is of known form, consisting of two
vertical cylindrical boilers one at each side of the car, with space between them for the
engines, these two boilers being connected by a large transverse cylindrical trunk
the axis of which is about the water level so that there is free communication between
the boilers both for steam and for water.
Within each of these vertical shells is a firo box cylindrical in its lower part where
the fire is and square in its upper part which is crossed in both directions by inclined
tubes through which the water circulates.
According to my present invention, I employ tubes graduated to different sizes,
the lower tubes which receive the first action of the fire larger in diameter than the
upper tubes which are closer together so as to utilise most effectively the heat of the
products of combustion before they ascend the chimney which rises through the steam
space above the fire box.
Boilers of the kind referred to have their shells usually made in two parts of equal
diameter, a lower part enclosing the lower part of the fire box and an upper part
surrounding the upper part of the fire box in which the tubes are fixed.
These two parts of the shell are provided with flanges which are bolted together
making a tight joint. When it is necessary to cleanse or repair the interior of the
boiler, the flanges are unbolted and the upper part of the shell is lifted off leaving
the upper part of the fire box and its tubes exposed. I enlarge the diameter of the
flanges and of the upper part of the shell so as to accommodate freely within the
latter the square part of the fire box, the diagonal of which is greater than the diameter
of the lower part of the fire box which is a circle having approximately the same
circumference as the square. In order to render the exhaust steam invisible as it
escapes from the chimney I lead it down an annular passage surrounding the chimney
within the upper part of the boiler, and allow it to pass by a mouth or mouths
directed obliquely upwards into the chimney where it springs from the fire box.
The exhaust steam, thus heated by its contact with the chimney and its mixture with
the products of combustion ascending the chimney, is rendered invisible or almost
invisible as it escapes from the chimney.

page_text: i
In order to heat the waste steam before its escape when it is not heated as above
described by the chimney arrangement, and also in order to heat the feed water for
the boiler, 1 pump the feed water through a pipe coil situated within the fire box
and I pass the waste steam into and through the space between this coil and the wall
of the fire box so that it can escape between the pipes of the coil, heated and mingled
with the products of combustion.
Dated this 2nd day of An 1880
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Tramway Locomotives.
1, WILLIAM ROBERT ROWAN, of Behrenstrasse 54, Berlin, in the Empire of
Germany, 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:-
Usually the crank shaft of a tramway locomotive engine has to revolve at con-
siderable speed and has to work the driving axle at a reduced speed by toothed or
friction gear.
As the car or bogie which carries the engine is mounted on springs
it has an up and down motion relatively to the driving axle, and this seriously
interferes with the action of the gearing by which this axle is worked.
To provide against this defect I, according to my invention, fix the engine
cylinders, piston rod guides and crank shaft bearings on a frame which at its one
end has bushes embracing the driving axle, and at its other end is pivotted to the
body of the car. This frame consequently oscillates with the car, but as it works on
the driving axle as a centre, there is no variation in the radial position of the
crank axle relatively to the driving axle and consequently the engagement of the
gearing remains constant.
The horn plates for the boxes of the driving axle may be curved to a circular
arc struck from the pivot of the frame as a centre, or if the horn plates are as usual
straight, this pivot is arranged in a sliding bearing which allows a little to and fro
longitudinal motion.
The boiler which I employ is of known form, consisting of two vertical
cylindrical boilers one at each side of the car, with space between them for the
engines, these two boilers being connected by a large transverse cylindrical trunk
the axis of which is about the water level so that there is free communication between
the boilers both for steam and for water.
Within each of these vertical shells is a fire box cylindrical in its lower part where
the fire is and square in its upper part which is crossed in both directions by inclined
tubes through which the water circulates.
According to my present invention, I employ tubes graduated to different sizes the
lower tubes which receive the first action of the fire larger in diameter than the
upper tubes which are closer together so as to utilise most effectively the heat of
the products of combustion before they ascend the chimney which rises through the
steam space above the fire box.
Boilers of the kind referred to have their shells usually made in two parts of equal
diameter a lower part enclosing the lower part of the fire box and an upper part
surrounding the upper part of the fire box in which the tubes are fixed.
These two parts of the shell are provided with flanges which are bolted together
making a tight joint. When it is necessary to cleanse or repair the interior of the
boiler the flanges are unbolted and the upper part of the shell is lifted off leaving
the upper part of the fire box and its tubes exposed. I enlarge the diameter of
the flanges and of the upper part of the shell so as to accommodate freely within the
latter the square part of the fire box, the diagonal of which is greater than the

page_text: diameter of the lower part of the fire box which is a circle having approximately
the same circumference as the square. In order to render the exhaust steam invisible
as it escapes from the chimney I lead it down an annular passage surrounding
the chimney within the upper part of the boiler and allow it to pass by a mouth or
mouths directed obliquely upwards into the chimney where it springs from the fire
box: The exhaust steam thus heated by its contact with the chimney and its
mixture with the producis of combustion ascending the chimney, is rendered
invisible as it escapes from the chimney.
Fig. 1 of the accompanying drawings is a central longitudinal section of a
locomotive according to my invention. Fig. 2 is a plan partly in section. Fig. 3
is a vertical section and Fig. 4 is a sectional plan taken at two different levels of one
of the two parts of the boiler. Fig. 5 is a part sectional plan shewing the adaptation
of the gearing for acting with a rack rail.
Referring first to Figs. 1 and 2, a is the main frame resting as usual by the
springs e el on the boxes of the axles p p². The engines are mounted on a separate
frame which at its one end is centred on the driving axle p and at its other end on
trunnions o o' working in bearings which are fixed on the main frame a.
On the crank shaft is the pinion which gears with the wheel r¹ on the axle p.
In cases where it is desired to employ a rack rail for ascending gradients the gearing
may be modified as shewn in Fig. 5. In this case the gearing is in duplicate one
set ou each side of a middle wheel R which is toothed to gear with the rack rail,
and which is free to turn on the axle p.
In places where there is no rack rail the wheel R is clutched to the axle
p by
cone clutches n n' sliding on feathers on the axle p. As is seen in Figs. 1 and 2, the
boiler consists of two upright cylindrical parts C (11 connected by a cross com-
munication b. Each boiler part cel is constructed as shewn by Figs. 3 and 4
having in its lower part a cylindrical fire box which in its upper part is of square
form.
Across this upper square part in both directions are fixed inclined tubes t of
graduated sizes, the lowest being the largest in diameter, and the others less in diameter
and more numerous in each layer the higher the layer. On the casing of the
fire box is fixed a flange d spreading out in diameter to meet the flange d¹ of the upper
casing, which is large enough to give free space at the angles of the inner tube box.
On unbolting the flanges d d and the chimney flange m the whole of the upper
casing c can be lifted off giving access to the tubes. At the top of the boiler is the
inlet for the waste steam which has to descend the annular passage g¹ and pass by
an inclined mouth at k into the central tube g of the chimney, thus becoming heated
and mingled with products of combustion, so that as it escapes with these from the
chimney it forms no visible cloud.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. In a tramway locomotive, fixing the engines on a frame pivotted at one end
to the main frame and centred at the other end on the axle which it drives by gear,
substantially as and for the purpose set forth.
2. For a tramway locomotive, a boiler having an internal shell cylindrical in its
lower part forming the fire box and having its upper portion formed to receive
inclined tubes crossing it, the outer cylindrical casing being made in two portions,
the lower portion enclosing the fire box and the upper portion made larger for
enclosing the tube box and chimney, the two portions having flanges bolted together,
substantially as described.
3. In the tube box of a boiler such as is above referred to, the use of graduated
tubes, those in the upper layers less in diameter and greater in number than those in
the lower layers, as and for the purpose set forth.

page_text: 4. In the chimney of a tramway locomotive boiler the construction of an annular
passage communicating at its lower end with the central chimney tube, for waste
steam to be heated and mingled with the furnace gases, substantially as described.
Dated this 31st day of December 1889.
ABEL & IMRAY,
Agents for the Applicant.