IMPROVEMENTS IN STEAM TRAM CARS OR LOCOMOTIVES
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 Inven-
tion of "IMPROVEMENTS IN STEAM TRAM CARS OR LOCOMOTIVES."
Sealed the 20th April 1877, and dated the 13th November 1876.
PROVISIONAL SPECIFICATION left by the said Henry Merryweather and
Christopher John Wallace Jakeman at the Office of the Commissioners of
Patents on the 13th November 1876.
"
HENRY MERRYWEATHER and CHRISTOPHER JOHN WALLACE JAKEMAN, both of
Greenwich, in the County of Kent, Engineers. IMPROVEMENTS IN STEAM TRAM
CARS OR LOCOMOTIVES."
The first part of this Invention has reference to a method of absorbing or carrying
off the exhaust steam by means of dry air.
Within the smoke box is arranged a series of cones, having at its base an annular
nozzle or equivalent device delivering exhaust steam, which induces a current or
currents of hot air. This hot air intermingles with the steam, and the mixture
passes invisibly out of the chimney.
The supply of hot air may be drawn through the tubes from the fire-box, or from
any convenient heater or casing, or it may be obtained from several places simulta-
neously. The arrangements in this respect will obviously vary according to the
class of boiler employed.
In some cases we provide a small jet of live steam under the exhaust steain
nozzle or device to assist the mixing of the exhaust steam and hot air.
The chimney is made by preference of a conical form with its larger diameter
uppermost, and narrowed at its lower end to facilitate the admixture of the steam
and hot air at the narrowest part of the chimney, and to afterwards quietly
distribute the mixture.
We do not limit ourselves to the use of a single exhaust nozzle nor to any particular
form of nozzle or jet, as the details may obviously be varied without departure
from the distinctive character of this part of our Invention.
Our Invention furthermore relates to a method of condensing part of the exhaust
steam by air, and subsequently disposing of such air and of the steam remaining

page_text: .
uncondensed.
We provide a tank or vessel into which the exhaust steam is
delivered, and wherein partial condensation or deposit of water takes place; the
water may be drawn off in any convenient manner. The steam from this tank is
conducted to a nozzle whose diameter is such as that the pressure of the steam shall be
constant or nearly so as distinguished from the intermittent puffs from the engines.
The nozzle is surrounded by cones arranged concentrically and consecutively
increasing in diameter, thus a current of cool air is induced, which by contact with
the exhaust steam condenses a portion thereof. The water of condensation may be
collected and delivered to the feed tank or disposed of in any other convenient
manner.
The remainder of the mixture of exhaust steam and air issuing from the largest
nozzle is conducted to a tank or vessel fitted inside with diaphragms of wire gauze,
bundles of wire, or other convenient collecting and condensing appliances, whereby
a further portion of the steam is condensed, the resulting water being collected and
disposed of as before.
The remaining steam and air are caused to pass into a surface condenser which
may conveniently be arranged upon the roof of the tram locomotive, but we do not
confine ourselves to this arrangement. The water from the lower part of this con-
denser flows into the feed tank, or is otherwise disposed of, and the air with the
small remaining quantity of vapour still in suspension is led from the highest part
of the condenser and thrown under a series of cones in the smoke box, thus urging
the fire, and at the same time getting mixed therewith sufficient dry air to render
the vapour practically invisible.
In some cases we use a jet or jets of live steam in conjunction with the cones to
promote the admixture of the dry air and vapour.
In some cases, where it is not netessary to condense so much of the exhaust steam,
we pass the steam and air from the nozzles before described into a chamber where
the condense water is collected, and thence into the chimney or smoke box, either
directly or through a heater without the intervention of other condensing apparatus.
We do not confine ourselves to the order of the arrangements described, as in
some cases it is expedient to pass the exhaust steam through a surface condenser
first, and it is obvious that the details of the arrangement may be modified to suit
the conditions under which it is applied.
Another part of our Invention has reference to arrangements whereby the steam
is shut off, and the brakes are applied automatically when the engine has attained
a given speed. To this end we use a centrifugal or other governor driven by or
from the locomotive wheels, and acting upon an equilibrium valve or equivalent
arrangement in the steam pipe leading from the boiler to the engine. The steam
is thus shut off on the engine attaining the prescribed speed. In order that the
brakes shall be applied at the same time, we arrange them to be operated by
means of a piston in a cylinder, the said piston being moved either by steam or
hot water from the boiler, or by other available pressure. In connection with this
cylinder we apply a valve arranged to be actuated by the governor in such wise as
to release or admit, as the case may be, the steam or other motive fluid to or from the
piston as required to put on or release the brake.
In some cases, instead of a centrifugal governor, we use as a governor a pump
driven direct from the engine, and discharging water through a small hole in a
cylinder having a spring loaded piston working within it; as the speed of the pump
piston and consequently the pressure against the spring loaded piston increases, the
said piston actuates the valve, thereby controlling the brakes and the supply of
steam to the engine.

page_text: 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 12th May 1877.
HENRY MERRYWEATHER and CHRISTOPHER JOHN WALLACE JAKEMAN, both of
Greenwich, in the County of Kent, Engineers. "IMPROVEMENTS IN STEAM TRAM
CARS OR LOCOMOTIVES.' "
The first part of this Invention has reference to a method herein-after described
of absorbing or carrying off the exhaust steam by means of dry air.
The Invention relates, secondly, to a method herein-after described of condensing
part of the exhaust steam by air, and subsequently disposing of such air and of the
steam remaining uncondensed.
And the third part of the Invention has reference to arrangements herein-after
described, whereby the steam is shut off and the brakes are applied automatically
when the engine has attained a given speed.
And in order that the nature of our said Invention and the manner of carrying it
into practical effect may be well understood, we proceed to describe the same with
reference to the accompanying Drawings, wherein Fig. 1 (Sheet 1) shews in trans-
verse section so much of an engine as is needful to illustrate the first part of our
Invention.
Within the smoke box a is arranged a series of hollow truncated cones, b, 61, 62,
6, 6, 65, (which we call "cones,") having at its base an annular nozzle c, delivering
exhaust steam from the tank d, which tank receives such steam from the engines
through the orifices e, e; the exhaust steam induces a current or currents of hot air
in the direction of the arrows; this hot air intermingles with the exhaust steam and
the mixture passes invisibly out of the chimney.
The supply of hot air is drawn through the tubes f from the fire-box; g is a small
nozzle through which a jet of live steam regulated by the cock h may be projected
when requisite to assist the mixing of the exhaust steam and hot air, and to raise
their temperature.
The chimney i is made by preference of a conical form, as shown, with its larger
diameter uppermost, and narrowed at its lower end to facilitate the admixture of
the steam and hot air at the narrowest part of the chimney, and to afterwards
quietly distribute the mixture.
We do not limit ourselves to the use of a single exhaust nozzle or to any par-
ticular form of nozzle or jet as the details may obviously be varied without departure
from the distinctive character of this part of our Invention. Thus, for example, we
have obtained very satisfactory results with a modification of apparatus in which, in
lieu of using a single annular nozzle c, we employed a second nozzle of similar con-
struction, but larger diameter at the base of the cone 6, and we caused the exhaust
steam to pass simultaneously partly through each of the two annular nozzles. It
will be evident that in such an arrangement the lower nozzle might be tubular
instead of annular, but we much prefer the annular form.
Fig. 2 (Sheet 2) shews in longitudinal vertical section, and Fig. 3 in transverse
section, so much of an engine as is needful to illustrate the manner of performing
the second part of our Invention; d is the tank or vessel into which the exhaust
steam is delivered from the engine cylinders through the orifices e, e; in this tank
partial condensation or deposit of water takes place; the water may be drawn off in
any convenient manner, preferring to use a cock provided with a zig-zag pipe as
shewn at k, so that by keeping the cock slightly open water of condensation drains
off, and any steam passing down the pipe is condensed before it can escape into the
atmosphere. From the tank d the exhaust steam passes by the pipe into a surface
condenser, which in the example illustrated consists of sets of shallow thin metallic
boxes in communication one with another at their respective ends, alternately by
short pipes, m', as seen best in Fig. 2.
Although we have shewn the condenser arranged upon the roof of the locomotive,

page_text: it may obviously be placed in any other convenient situation, and we do not confine
ourselves to the precise construction of condenser illustrated. The water from the
lower part of this condenser flows through the pipe n into the feed tank n¹, or it
may be otherwise disposed of; and the uncondensed steam is conducted by the pipe o
to the tank or vessel o¹, fitted with tubes o, by contact with which a further portion
of the steam is condensed, the resulting water flowing by the pipe o into the feed
tank n. The steam not condensed by contact with the outer surfaces of the tubes o
flows by the pipes p through the nozzle p', and thence through the tubes o²; thus
currents of cool air are induced, which cool air intermingles with the exhaust steam
and the mixture passes by the large pipe q into the cones 64, 65, passing up the
chimney and away invisibly. When needful, as, for example, in damp weather, a
jet of live steam is allowed to flow through the nozzle g, and the entire series of
cones, thus inducing a flow of hot air in the direction of the arrows to assist in
the absorption of any remaining exhaust steam or vapour; is a cock, by opening
which, more or less, the whole or a portion of the exhaust steam may be projected
through the nozzle c, and enter series of cones, b, 61, 62, 63, 64, 65; thus to suit con-
venience the apparatus may be worked as described with reference to Fig. 1, or part
of the exhaust steam may be disposed of in that way, and the remainder by con-
densation, as already described with reference to the Figures 2 and 3, now under
notice.
Fig. 4 (Sheet 1) shews in side elevation so much of an engine as is needful to
illustrate one manner of performing the third part of our Invention; 1 is a centri-
fugal governor driven from the axle of the locomotive wheels 2, through the friction
wheels 3 and 4; this governor is of similar construction to that which is shewn to
a larger scale in Figs. 5 and 6, herein-after described; the friction wheels, 3 and 4,
are kept in contact by the pressure of the spring 5, through the tension rods 6; the
governor 1 operates the rock shaft 7, which in turn through the rod 8 operates the
equilibrium valve 9, placed in the steam pipe 10, leading from the boiler to the
engine; the rod 8 is also connected to the valve 11, which governs the flow of steam
or water from the boiler to the brake cylinder; 12, 13 are the brake blocks carried
by hangers 21, 21, working on studs 22; a shaft 23 passes across the engine,
having its bearings in the hangers; it carries a bent lever 23* at one end, and a
short arm (corresponding to the shorter arm of lever 23×) at the other end; the
lever 23 is connected to the rod of the brake piston; also by a push rod 24 to the
brake hanger 21*; a similar push rod connects the short arm at the opposite side
of the engine to the hanger that is opposite 21* (not shewn); 25 is a pedal arrange-
ment whereby the lever 23* may be actuated and the brakes applied by the feet.
The modus operandi is as follows:-When the speed of the engine exceeds the
given maximum for which the governor is adjusted the governor expands and
through the rock shaft 7 and rod the valve 9 is moved, thus arresting the flow of
steam through the pipe 10 from the boiler to the engine cylinders; simultaneously
the valve 11 is opened, thus admitting steam or hot water from the boiler through
the pipe 15 to the brake cylinder 12 and applying the brake blocks 13 to the
wheels.
Figs. 5 and 6 (Sheet 1) shew respectively in side elevation and in end elevation
parts of an engine embodying the third part of our Invention in a modified form.
1 is the centrifugal governor driven as in the preceding arrangement from the axle
of the locomotive wheels 2 through the friction wheels 3 and 4 kept in contact by
the pressure of the spring 5 through the tension rods 6. The governor 1 operates
the small slide valve 11 (seen best in Fig. 6). The ports over which this valve
slides should be of small area, say about of a square inch, in order to minimise
the work thrown on the governor; one of these ports communicates with the pipe 16
leading to the valve box, and the other with the exhaust pipe 18. The valve box 17
contains a differential piston valve 19 whose normal position is as shewn in Fig. 5,
the lateral openings from the main steam pipe 10 and to the cylinders being open.
12 is the brake cylinder as before. The box of the slide valve 11 receives steam
from the boiler through the pipe 15. Upon the movement of the governor, and

page_text: consequently of the slide valve 11, the port communicating with the pipe 16 is
opened, thus giving steam to the larger end of the differential valve 19 and thereby
causing the valve to rise and close the lateral openings in the steam pipe 10, thus
cutting off the supply of steam to the cylinders. Should the speed continue even
momentarily in excess of the maximum for which the governor is adjusted steam
flowing through the lower portion of the valve box 17 and along the pipe 20 will
enter the brake cylinder 12 and apply the brake blocks 13 to the wheels 2, 2x.
When the speed has been so far slackened that the port leading to the pipe 16 is
closed by the action of the governor the said pipe is by the consequent position of
the slide valve 11 in communication with the exhaust pipe 18; thus the steam from
the brake cylinder 12 and valve box 17 will have free escape. It will be evident
that any tendency on the part of the valve 19 to stick will be effectually overcome
by the pressure of the steam on its upper surface.
In some cases instead of a centrifugal governor we use as a governor in connection
with either of the combined valve and brake arrangements herein-before described
a pump driven direct from the engine and discharging water through a small hole
in a cylinder having a spring-loaded piston working within it. This arrangement
is shewn in Fig. 7, wherein 2 is the engine wheel; 26, its axle; 27, an eccentric
wheel which by a strap 28 and rod 20 operates a pump plunger 30. This pump
draws water or other liquid from the cistern 31, forcing it along the pipe 32 (pro-
vided with an air vessel 33) and into the cylinder 34 whose piston 35 is loaded with
a spring 36. The piston rod 37 is connected to the rod 8, Fig. 4, when employing
the valve and brake arrangement shewn in that Figure or to the small slide valve 11,
Figs. 5 and 6, when employing the valve and brake arrangement shewn in those
two Figures. The water or other liquid forced into the cylinder 34 returns to the
cistern 31 by the pipe 38, the size of which is duly proportioned to the intended
speed.
As the speed of the pump plunger and consequently the pressure against the
spring loaded piston 35 increases the said piston actuates the valve 9 (Fig. 4) or 11
(Figs. 5 and 6) as the case may be, thereby controlling the brakes and the supply of
steam to the engine.
Having described the nature of our said Invention and explained the manner of
performing it, we desire to have it understood that we do not claim generally as of
this Invention either the passing of exhaust steam through a series of cones or the
controlling of the speed of the engine by the use of a governor and valve, as arrange-
ments of apparatus for these purposes are described in the Specification of a previous
Patent granted to us, being No. 3727, dated 23 September, 1876. Furthermore
we would remark that we do not intend to claim 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 purposes 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,―
1. The use in the smoke box a of the apparatus b, b¹, b², bs, b4, 66, c, g, constructed,
arranged, and operating as shewn in and described with reference to Fig. 1 of the
Drawings for the purpose specified.
2. The method herein-before described with reference to Figs. 2 and 3 of the
Drawings of disposing of the exhaust steam from the engine cylinders.
3. The combination of parts constituting the improved apparatus constructed,
arranged, and operating as shewn in and described with reference to Fig. 4 of the
accompanying Drawings for the purpose of automatically shutting off the steam and
applying the brakes when the engine has attained a given speed.
4. The combination of parts constituting the improved apparatus_constructed,
arranged, and operating as shewn in and described with reference to Figs. 5 and 6
of the accompanying Drawings for the purpose of automatically shutting off the
steam and applying the brakes when the engine has attained a given speed.
5. The use in conjunction with the valve and brake arrangement shewn in Fig. 4,
or with that shewn in Figs. 5 and 6 of the apparatus shewn in Fig. 7, in lieu of a

page_text: centrifugal governor for the purpose of automatically shutting off the steam and
applying the brakes when the engine has attained a given speed as herein-above
described.
In witness whereof, we, the said Henry Merryweather and Christopher John
Wallace Jakeman, have hereunto set our hands and seals, this Eleventh day
of May, in the year of our Lord One thousand eight hundred and seventy-
seven
HENRY MERRYWEATHER. (L.S.)
C. J. W. JAKEMAN.
(L.S.)