IMPROVEMENTS IN TRAMWAY LOCOMOTIVES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO OTHER STEAM ENGINES
Year: 1876

page_text: LETTERS PATENT to Henry Merryweather and Christopher John Wallace
Jakeman, both of Greenwich, in the County of Kent, Engineers, for the
Invention of "IMPROVEMENTS IN TRAMWAY LOCOMOTIVES, PARTS OF WHICH
IMPROVEMENTS ARE ALSO APPLICABLE TO OTHER STEAM ENGINES."
Sealed the 16th March 1877, and dated the 23rd September 1876.
PROVISIONAL SPECIFICATION left by the said Henry Merryweather and
Christopher John Wallace Jakeman at the Office of the Commissioners of
Patents on the 23rd September 1876.
HENRY MERRYWEATHER and CHRISTOPHER JOHN WALLACE JAKEMAN, both of
Greenwich, in the County of Kent, Engineers. "IMPROVEMENTS IN TRAMWAY
LOCOMOTIVES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO OTHER
STEAM ENGINES."
This Invention of improvements in tramway locomotives, parts of which
improvements are also applicable to other steam engines, relates, first, to a method
of disposing of the exhaust steam without noise or visible vapour. The exhaust
steam from the engine is conducted into a combination of several nozzles, the upper
parts of which are open to the air, and the lower ends terminate in a trumpet-
shaped tube, the end of which is in communication with a closed ash pan or
chamber in direct connection therewith. The nozzles are surrounded by a cone,
which may be of metal, and which is lined inside with felt or other non-conductor
of sound, and the whole apparatus is enclosed in a case, preferably of wood lined
with a similar material to the lining of the cone. By this arrangement noise is
prevented. The exhaust steam by this arrangement draws in with it a large
volume of air, whereby part of the steam is condensed and falls to the bottom of
the ash pan or reservoir provided to receive it at or near the outlet of the trumpet
shaped pipe before referred to, and the uncondensed portion of the exhaust steam
passes in combination with a large volume of air through the fire, and is thereby
effectually disposed of, while at the same time the fire is urged in proportion to the
quantity of steam used, and consequently steam is generated to meet the varying
requirements of the engine.
Arrangements are provided to regulate the supply of air, and also the pressure

page_text: of the exhaust. This part of our Invention is applicable also to other stearn
engines where a chimney or visible exhaust steam are not admissible.
In applying this arrangement to stationary boilers or others requiring to be fired
when the engine is at work we arrange a valve whereby the exhaust steam may be
turned over the fire or elsewhere during the time the fire-door is open to prevent
the inconvenience of flames coming out of the fire-hole. This apparatus will also
work in a horizontal or other position, although the foregoing refers to the vertical
position, which we prefer. We also pass the escape steam from the safety valves
into the closed ash pan, which going in without the admixture of air deadens the
fire and checks the production of steam.
By the addition of a nozzle of smaller diameter and a steam connection between
the boiler and apparatus, it may be used also to blow the fire when the engine is
not at work.
The second part of our Invention consists in a method of automatically control-
ling the speed of the engine so that it may never exceed a given rate. To this end
we use a centrifugal governor, which we so apply as that it shall be driven by the
rotation of the wheels which carry the engine, and shall act upon a valve in the
exhaust pipe of the engine, closing that valve when the speed has reached the given
maximum.
We prefer to use a governor provided with busk springs in place of jointed
levers, but any governor unaffected by the oscillation of the engine will answer the
purpose. The governor may be placed upon the axle or driven by means of gearing
or belts, but we prefer to drive it by friction wheels multiplying the speed from the
axle in order to ensure greater promptitude of action in the governor.
The valve in the exhaust pipe may be an ordinary throttle valve or any similar
arrangement, but we prefer to use an equilibrium piston valve. This arrangement
not only checks the speed of the engine when steam is on, but also in descending
inclines by preventing the escape of air from the cylinders, which are then working
pumps,
as air
In some cases an air valve is placed on the steam chest or other equivalent part
of the engine opening inwards to ensure enough air being admitted to the cylinder
to make the counter pressure for the purpose of checking the speed of the engine.
Piston valves may be used for the engines, or the ordinary slide valves may be
provided with a spring to prevent them leaving their faces until a sufficient back
pressure has been obtained."
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said Henry Merryweather and Christopher John Wallace Jakeman in the
Great Seal Patent Office on the 23rd March 1877.
HENRY MERRYWEATHER and CHRISTOPHER JOHN WALLACE JAKEMAN, both of
Greenwich, in the County of Kent, Engineers. " IMPROVEMENTS IN TRAMWAY
LOCOMOTIVES, PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO OTHER
STEAM ENGINES."
This Invention has for its object improvements in tramway locomotives, parts of
which improvements are also applicable to other steam engines.
Fig. 1 of the Drawings is a sectional elevation of part of a locomotive embody-
ing our improvements. Fig. 2 is an end elevation of the same.
The first part of our Invention has reference to a method of disposing of the
exhaust steam without noise or visible vapour. For this purpose the exhaust steam
from the engine is conducted through the exhaust pipe a, closed tank b, and pipe c
into a combination or series of nozzles d, d', d², ds. These nozzles are at their
wider ends open to receive air; their other ends terminate in one end of a tube c,
whose other end is in communication with a closed ash pan f through a chamber
g
in direct connection therewith. The said chamber g is provided with baffle plates g¹

page_text: as shewn to arrest water held in suspension by the passing steam, and which water
is deposited at g, whence it may be drawn off by the cock g³. The nozzles d, ď³,
d², d³, are surrounded by a cone h, which may be of metal, and is lined inside with
felt or other non-conductor of sound, and the whole apparatus is enclosed in a case i,
preferably of wood lined with a similar material to the lining of the cone. By
this plan noise is prevented. The exhaust steam by this arrangement draws_in
with it through an opening in the lower part of the case regulated by a valve k a
large volumn of air, whereby part of the steam is condensed and falls to the
bottom of the chamber at g2, and the uncondensed portion of the exhaust steam
passes in combination with a large volumn of air through the fire, and is thereby
effectually disposed of, while at the same time the fire is urged in proportion to the
quantity of steam used, and consequently steam is generated to meet the varying
requirements of the engine.
To regulate the pressure of the exhaust a tapered spindle is arranged within
the steam nozzle m, the position of which spindle in relation to that nozzle may be
varied by moving the lever n through the rod o, thus varying the area for the
passage of exhaust steam between the spindle and nozzle. In some cases we pass
the exhaust steam from the pipe a through a superheater before admitting it to the
series of nozzles d, d, d², d³, in order that the exhaust steam may be partially
dried before passing under the fire.
This part of our Invention is applicable also to other steam engines where a
chimney or visible exhaust steam are not admissable. Such an application is
illustrated in Fig. 3, like parts being marked with the same letters of reference as
in the preceding Figures. The nozzles d, d¹, d², d³, and m in this case are arranged
vertically above the chamber g. This chamber is in communication (as before).
with the ash pan f.
In applying this arrangement to boilers requiring to be fired whilst the engine is
at work and the exhaust steam is passing through the nozzles we employ the valve
arrangement shewn, whereby the exhaust steam and air are turned over the fire (or
it may be elsewhere) during the time the fire-door is open, the object being to
prevent the inconvenience of flames coming out of the fire-hole..
From the chamber ga pipe or passage p leads to the fire-box q, or it may lead
elsewhere. Between the chamber g and the ash pit f is interposed a valve r, and
the pipe or passage p is furnished with a similar valve 8. The two valves 7 and 8
are connected by a rod t, so that when the one valve is open the other will be
closed. The rod t is operated by a counterweighted lever u having its fulcrum
at u. When this lever is in the position corresponding to the open position of the
lower valve (in which positions the parts are shewn in the Drawings) the end of
the lever traverses the fire-door v, which therefore cannot be opened without first
so moving the lever as to close the valve r and open the valve 8.
w (Fig. 1) is a pipe whereby the escape steam from the safety valves x passes
into the closed ash pan f, and going in without the admixture of air deadens the
fire and checks the production of steam.
.
The second part of our Invention consists in a method of automatically con-
trolling the speed of the locomotive engine so that it may never exceed a given
rate. To this end we use a centrifucal governor, which we so apply as that it
shall be driven by the rotation of the wheels which carry the engine, and shall act
upon a valve in the exhaust pipe of the engine, closing that valve when the speed
has reached the given maximum.
To the engine frame 1 are suspended two sling links 2, each carrying a bush 3.
Within the bushes 3 works the governor spindle 4, on which is fixed the friction
pulley 5. This pulley is driven by contact with the wheel 6 on the axle 7, the
pulley being kept against said wheel by means of the tension rods 8 and spring 9.
On the spindle 4 is fixed a collar 10, and a second collar 11, similar in form but not
open right through, is free to move endwise on the end of the spindle 4. The two
collars are connected by the busk springs 12 carrying the balls or weights 13. The
collar 11 is recessed to receive one end of a rod 14, which end is in the form of a

page_text: knob or flange, and has thin rings of steel placed loosely at each side of it. The
knob or flange is held in the recess between the steel rings by means of an annular
cover 15 screwed on to the collar 11, thus leaving the collar free to rotate inde-
pendently of the rod 14. The other end of this rod passes freely through a holo
in an arm 16 fixed on a rock shaft 17. The rod is provided with nuts at each side
of the said arm so as to operate the arm when moved endwise by the governor.
By means of these nuts the relative positions of the governor and the valve
herein-after described may be adjusted. On the rock shaft 17 is another fixed arm
18 jointed to the rod 19 of an equilibrium valve 20, which in the Drawing is
represented as a hollow piston valve. This valve is situate in the exhaust pipe a.
It will be evident that any excess of speed over that to which the governor is
adjusted will have the effect of causing the governor to close the valve 20. This
arrangement not only checks the speed of the engine when steam is on, but also in
descending inclines by preventing the escape of air from the cylinders, which are
then working as air pumps.
In some cases an air valve may be placed on the steam chest of the engine, as
shewn at 21 in Fig. 2, or it may be placed on the steam pipe or cylinder. This
valve, by opening inwards, will ensure enough air being admitted to the cylinder
to provide the counter pressure for the purpose of checking the speed of the
engine.
Piston valves may be used for the engines, or the ordinary slide valves may be
provided with springs, as shewn at 22 in Fig. 2, to prevent the valves leaving their
faces until a sufficient back pressure has been obtained.
Having described the nature of our said Invention, and the manner of carrying
it into practical effect, we hereby declare that we do not intend to claim as of our
Invention or the exclusive use of any of the mechanical parts of the apparatus
herein-before shewn and described when taken separately and apart from the
combination or application thereof in manner and for the purpose herein described,
but what we consider to be novel and original, and therefore claim as secured to us
by the herein-before in part recited Letters Patent is,-
First. The method, substantially as herein-before described with reference to the
accompanying Sheet of Drawings, of disposing of the exhaust steam from the
engines.
Second. The method, substantially as herein-before described with reference to
Figs. 1 and 2 of the accompanying Drawings, of automatically controlling the
speed of the locomotive engine by means of a valve arranged to control the exhaust
steam passage.
In witness whereof, we, the said Henry Merryweather and Christopher John
Wallace Jakeman, have hereunto set our hands and seals, this Twenty-third
day of March, in the year of our Lord One thousand eight hundred and
Reventy-seven.
HENRY MERRYWEATHER. (LS.)
C. J. W. JAKEMAN.
(L.S.)