Improvements in Steam Motive Power Engines, Especially Applicable to Steam Tramcars or Road Cars.
Year: 1897

page_text: Date of Application, 29th June, 1897-Accepted, 21st Aug., 1897
Improvements in Steam Motive Power Engines, Especially Applicable
to Steam Tramcars or Road Cars.
I, ARTHUR PILLSBURG DODGE, of 622, Lord's Court Building, New York, in the
United States of America, Lawyer, 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, and accompanying drawings, that
is to say:
My invention relates to locomotive steam cars and is especially designed to meet
the requirements of street car service.
My motor comprises a boiler placed below the car body having means whereby
it may be charged with hot water and steam at a maximum pressure from a charging
station, and an auxiliary fire box carrying a small fire which compensates for the
heat lost by radiation from the boiler, so that the necessary steam pressure in the
boiler may be maintained.
I aim to provide a steam car that shall be entirely free from all objectionable
features, such as noise, escape of exhaust steam, cinders, smoke, etc., which render
the ordinary locomotive type of motor unfit for street car use.
Among other things my improvement consists in; (a) preventing the appearance
of steam at any point on the motor; (b)preventing all possibility of leaky joints in
the condenser; (e) providing means for heating the cars, either by direct radiation
from the smoke pipe or by either direct or exhaust steam; (d) insuring such an
arrangement of steam dry pipes, steam-dome, and cylinder feed pipe connections
as shall prevent "priming" of water from boiler to cylinders with the steam;
and (e) utilizing the hot gases passing through the smoke pipe for superheating
the steam.
In the accompanying drawings:
:-
Figure 1 is a longitudinal section of a motor car the seat on the far side being
also shown in section.
Figure 2 is a transverse section of Figure 1 on line 2-2.
Figure 3 is a transverse sectional view of Figure 1 on line 3-3 showing the
interior of the cab or vestibule.
Figure 4' is a view similar to Figure 1 but showing the boilor and the operating
connections in side elevation.
Figure 5 is a sectional plan view of the motor.
Figure 6 is a detail view of part of the overhead condenser.
Figure 6 shows a modification.
Figure 7 shows another embodiment of the principle upon which my condenser
is based.
Figure 8 is a plan view of the same partly in section.
Figure 9 is a plan view of a modified form of condenser.
Figure 10 is a detail view.
Figures 11 and 12 are detail views of valves.

page_text: Figure 13 is a side view of the boiler showing an air pump, and air relief system
for the condensers.
Figure 14 is a plan view of Figure 13
Figure 15 is a modified form of steam dome.
Figure 16 shows a modified arrangement of the dry steam pipe under the seat.
In these drawings:
A is a small fire box in which coal or liquid fuel is burned and A is the boiler
of tubular type beneath the body of the car. A grate is shown at A2 and an ash
pan A³ in connection with the fire box A. From the smoke box A' of the boiler
the products of combustion pass into a smoke pipe S above the boiler and between
it and the bottom of the car so that hot gases pass over the surface of a dry steam
pipe T within the smoke passage S" and which is connected with the steam space
at the top of the boiler by the pipes T arranged at different points. The dry
steam pipe has a forward vertical extension through the platform forming a
steam dome in the cab. The smoke pipe extends upward through the opposite
platform and through the other cab as shown in Figure 1.
In a steam boiler of the horizontal and clongated form shown, the water space
above the crown sheet is limited, and safety requires that the water line of the boiler
shall be maintained well above it, thus making the steam space very small, and
such causes as change of level at grades, foaming, and the like create a tendency
to prime or pass water over to the cylinders with the steam. The arrangement
of the dry pipe and its connections obviates these defects; it is also apparent that the
products of combustion passing through the smoke pipe S and around the steam
dry pipe will tend to superheat the steam therein and to prevent losses by
condensation:
The steam is taken from the steam dome through the pipe O, extending into
the smoke arch A, where its branches O¹, 02 extend to the cylinders E. The live
steam is thus superheated in these pipes. This pipe O has a cut off valve 0³ and
pressure reducing valve V operated by a lever VI connected to the valve in any
suitable manner to regulate the spring pressure thereon. The motorman's seat
is shown at X.
In my motor I dispense with the ordinary throttle valve and use instead the
reducing valve V in combination with mechanism for changing the point of cut
off at the cylinders, and by this combination the speed of the motor is regulated.
This adjustable cut-off mechanism is controlled by a wheel W in the cab, the
shaft of the wheel being connected with a rocker shaft 1 which is connected by
links 2, hell cranks 3 and links 4 with a link motion comprising a slotted link 5,
connected by eccentric rods 6, to a pair of eccentrics on the car axle. The slots
in the links receive blocks on the ends of the valve rods 7 which are connected
with the slide valve of the cylinders and by turning the wheel the motorman can
regulate the point of cut-off and at the same time by adjusting the pressure
reducing valve he can secure any desired initial pressure at the cylinder and thus
regulate the speed of the motor. A wheel W having a hollow shaft W surrounds
the wheel Wi and its shaft and' this hollow shaft Wa is connected with suitable
brake mechanism not shown. These shafts work in a standard W³.
The exhaust from the cylinders E, E, passes through pipes E11 into a transverse
condenser F and it thence passes through pipes K³ to the overhead condenser H,
said pipes K³ being preferably located in the corners of the car and being connected
at their lower ends with the exhaust pipes E. From this overhead condenser
placed above the roof of the car the water of condensation is drained off through
the pipes H into a lower condensation chamber L supported on the car truck 'below
the boiler. The pipes H5 have horizontal extensions Hunder the car seat and
these are connected with the condensation chamber L by vertical branches H
provided with valves H³.
In order to prevent any show of steam at the cylinders I connect the cylinder
cocks with the transverse condenser F by a pipe 10 and these cocks are controlled
by connections leading to levers E' in the cabs at the opposite ends of the motor.

page_text: I provide a safety valve at D in a pipe D' leading from the steam dome and this
pipe connects with the rising exhaust pipe K³ to discharge the steam invisibly
into the condenser system.
The water of condensation may be returned to the boiler from the tank Lthrough
the pipe B which connects with a pump P operated from the car axle and con-
nected by a pipe P¹ with the water leg of the boiler. A stop valve P and a check
valve P are arranged in this pipe, the check valve closing towards the pump. The
pipe B is connected as shown in Figure 14 with the pipe B and the latter is
connected with the transverse condenser F and thus the water of condensation
may be removed from the condenser F and passed into the boiler. Water may be
led to the ash pit through the pipes P2 P3 from the tanks L and F so that the ash
pit may be kept cool. A stop and check valve P³ is provided in the pipe P. A
similar pipe may conduct water to the ash pit from the overhead condenser.
For relieving the condenser system of air I either provide the air pump M
Figure 13 connected with the top of the tank L by pipe G and with the fire box A¹
either above or below the rate thereof by the pipe I, by which means any water
vapor mingled with the air removed from the condenser system is discharged
invisibly into the furnace; or tanks L and F and also the condenser H may be
connected to the fire box for the same reason without using the pump.
Each of such connecting pipes is provided with a stop and check valve opening
towards the fire box.
I have shown the air relief pipe H2 in Figure 4 leading from the head box of
An
the condenser H and the stop and check valve of this pipe is shown at 13.
air relief pipe G is also shown in this figure as connecting the tank L directly with
the furnace.
The pipe leading from the air pump M is provided with a branch I' which connects
with an air heater pipe in the transverse condenser F and thence by way of the
branch with the smoke pipe S to increase the draft therein the air thus being
heated in the condenser F before it enters the smoke passage.
1 construct my main overhead condenser from double tubes H, H one being
arranged within the other, steam being admitted to the narrow space between the
inner and outer tubes, and air passing on the opposite surfaces. The tubes are
connected to the head boxes, H, H", as shown so that the air passing through the
inner tubes and surrounding the outer tubes will cool the same and condense the
steam lying between the tubes, the water of condensation draining into the head
boxes and thence into the drip pipes H. To prevent the expansion and contraction
of the condenser tubes from causing leaky joints I may either corrugate the tubes
or I may curve them in the arc of a circle.
If I circumferentially corrugate the inner or outer tube of each pair or both,
see Figures 1 and 6 any unequal expansion will be compensated for by a bellows
like action of the corrugated tubes; if I bend the tubes in the arc of a circle,
Figures 1 and 4 they will be allowed slight lateral flexion under changes in
temperature thus relieving the joint from strain. The tubes can be inserted inside
one another as though they were straight.
In Figure 6 I have shown a modified form of condenser in which a plurality of
groups of tubes with their head boxes coupled together are arranged in a trans-
verse direction. This condenser is placed upon the car roof and a shield is placed
on either side of the condenser so that the motion of the car will cause the air to
pass in at one end, through the tubes of the condenser and out at the other end
and side.
The inner air tube H is provided with small openings Figures 1 and 6 prefer-
ably formed through nipples 101 projecting into the steam space so that the steam
issuing from the steam space between the inner and outer tubes will be projected
in jets across the air tube and will be diffused through the tube to be condensed
on the inner walls thereof. A double condensation thus takes place, part taking
place in the space between the tubes and part within the air tubes. The water of
condensation from between the tubes is led off by the pipes H5 while any water

page_text: from the inner tubes will be caught by a trough, H18 Figure 1 to be conducted to
any suitable place.
Figure 6 shows that the inner and outer tubes may be straight instead of curved.
Figures 7 and 8 show modifications of this condenser in which the outer tubes
are omitted and the open air tubes H are connected to the steam head box by jet
nipples. The air tubes extend transversely of the car roof and their outer open ends
are arranged to discharge into open troughs Ho..
The steam passing through the nipples will be condensed before the open end
of the tube is reached and there will be no sliow of steam at the ends of the tubes
or noise of exhaust.
The condenser may assume the circular form shown in Figure 9.
Figure 10 shows the detail construction of the nipple joint, 15 being the nipple
proper having a flange 16. The air tube H fits against this flange and a coupling
sleeve 17 completes the joint.
I have shown a tank Q extending vertically of the cab to receive the water from
the overhead condenser, and to discharge it into the boiler after receiving a full
supply:
A pipe Q3 connects the top of the tank with the condenser while a second pipe Q³
leads the water from the tank to the boiler.
A pipe Q2 connects the top of the tank with the steam space of the boiler or
with the steam dome C'as shown in Figure 3. These pipes Q Q are connected with
the tank through a valve Q
In one position of the valve the water is allowed to enter the tank from the con-
denser, the steam meanwhile being cut off, while in the other position of the valve
the condenser is cut off from communication with the tank and the steam pipe
is opened to the tank so that the steam pressure acting at both ends of the tank
will be equalized and the water will flow from the lank into the boiler. The
pipe is provided with a stop and check valve while the pipe Q³ has a similar
valve Q8 opening towards the boiler. A type of this combined stop and check
valve is shown in Figure 11.
There may be one of these tanks at each end of the car.
I have shown the valve Q' as adapted for manual operation but it will be under-
stood that a suitable float, shown in dotted lines at Y and trip mechanism may
be used to operate the valve automatically when the tank has been filled to a
certain point.
For heating the car I use the heat radiated from the smoke pipe S. I
cover this pipe by a jacket S of non-conducting material arranged close under
the car floor and providing a space from which the hot air may be taken through
registers S in the floor of the car and arranged centrally thereof. Heater pipes K
are also arranged under the seats and these are connected at one end to the rising
exhaust pipes K³ before described, by the branches K and at their other ends tho
heater pipes connect with the return drip tubes H6 H6 by the pipes K', suitable
valves being provided at K³ to control the admission of exhaust steam into these
pipes K. The water of condensation from these pipes passes through the branch
pipe K into the horizontal drip pipes 6 and thence to the condensation chamber L.
I provide pipes K6 connecting with the live steam pipe O for heating these
pipes K, valve K7 being used to control the supply of live steam to these heaters.
In Figure 16 I show a modification in which the smoke pipe and dry pipe are
above the floor and under the seat.
A gage glass indicator is arranged in the cab so that the motorman may ascertain
the level of the water in the boiler. This consists of a glass N having an air relief
valve N³ and a pipe N¹ connecting with the boiler at the point where it is desired
to maintain the water line. This pipe N' may be attached slightly below the water
line and it is obvious that if a free passage is established through this pipe and
gage glass by opening the air cock N³ the water in the boiler above the level of
the pipe N would be forced through it by the pressure in the boiler; in like
manner as the steam which may occupy the gage glass is much exposed it will

page_text: quickly condense and the same result follow: but as soon as the water level is holow
the mouth of the pipe N the steam will replace the water in the top of the gauge
glass. If air collects in the top of the tube it will have to be set free by means
of the air cock N.
As a modified form of the steam dome I show in Figure 15 a vertical cylin-
drical shell having smoke tubes and adapted to be placed in the forward vestibule
of cab and immediately over the smoke box A to which it is secured. This steam
dome is connected with the boiler at a plurality of points. The hot gases passing
through the tubes serve to superheat the steam in the dome. In this plan the
horizontal portion of the smoke pipe S is omitted as is also the horizontal dry
pipe.
In charging the boiler I employ a charging valve R" and coupling nut R™.
The seats of valves R¹ R" are adjacent to each other and open in opposite directions:
The part of the device carrying the check valve R' is permanently carried by
the boiler while that part which carries the stop valve R is permanently carried by
the charging boiler at the charging station where the motor derives its charge of
hot water and steam for the trip or trips.
The two parts of the device are attached to or detached from each other by
operating the coupling nut R
Instead of charging the boiler through the valve R on the boiler it may be
charged through the lank Q and said tank for this purpose has an inlet pipe Q7
extending therefrom.
In the operation of the motor, the first movement is to connect the charging
valve R to a stationary boiler below the water line of said boiler preparatory to
filling the motor boiler with water. I prefer that the pressure on the stationary
boiler should not be less than 200 pounds to the square inch. Having made this
connection properly, with the valve R closed, water from the charging boiler is
admitted to the said valve freely, and then that valve is opened gradually, when
the water will pass through it and the check valve R to the motor boiler. When
the boiler is filled to the proper height, the valve R is closed and the coupling
nut R disconnected, the check valve preventing the water in the motor boiler
from escaping. Having placed a good hard coal fire in the fire box A¹ the motor
is ready to start.
Having opened the valve 09 to let the steam to the operating parts, and having
the pressure reducing valve set at zero and the reversing mechanism set centrally,
the motorman adjusts the pressure reducing valve to the pressure best suited for tho
grade and load, and increases the point of cut off until the desired speed is
obtained, and thereafter regulates this speed by the same method, except where
great variation requires that the initial pressure supplied by the pressure reducing
valve should be varied, when that valve is adjusted to meet it. The steam from
the boiler A passes through the dry pipe T, the dome C, the valve 0, the pressure
regulating valve V to tlie cylinders EE, via the forward smoke box and brauch
pipes. From the cylinders the exhaust passes by pipes to tank F where it drops
any condensation that may have taken place and passes through the pipes K to
the condenser H; here it is condensed and drained back to tank L, from which it
is either pumped to the boiler or allowed to collect. The air which collects from
the steam is either passed to the fire box, the air blast in the stack, or allowed to
escape freely into the ash pit, check valves in all these pipes preventing air passing
backwards in case a vacuum is formed in the condenser.
The check valves may be weighted to insure a perfect closure before a vacuum
is formed.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I claim
ia:-
1. A street car motor adapted to be propelled by steam consisting of a horizontal
boiler extending longitudinally under the car floor, a dry steam pipe extending

page_text: longitudinally of the car over the boiler and connected to the steam space thereof
at a plurality of points, a steam dome and connections therefrom to the engine
cylinders, substantially as described.
2. A street car motor adapted to be propelled by steam consisting of a horizontal
boiler extending longitudinally under the car Hoor, a steam dome, the engine
cylinders, the overhead condenser, the connections thereto from the cylinder.
exhausts, the drip tank below the car, the connections thereto from the overhead
condenser, and the air reliefs from the drip tank and overhead condenser, sub-
stantially as described.
3. A street car motor adapted to be propelled by steam characterized by the
following elements: a horizontal boiler extending longitudinally under the car floor,
a dry steam pipe above the boiler, a smoke pipe surrounding the dry steam_pipe;
a steam dome at one end of the boiler with connections to the cylinders; a condenser
system comprising the overhead condenser, the transverse condenser and drip tank
with pipe connections and valved air and steam relief pipes for the condenser
system.
4. In combination with the street car motor described in Claim 1 an air forcing
device and a pipe leading from it to the stack, said pipe being heated by passing
through a tank or jacket heated by exhaust steam.
5. In combination with the motor as described in Claim 1, the tank F below the
boiler and between the cylinders designed to receive the exhaust from the cylinders
and a pipe to conduct the steam from the cylinder cocks to the said tank F.
6. In combination with the motor of Claim 1 a water gage glass placed above
the water line of the boiler and having a pipe connection with the boiler at or near
the water line, and an air relief valve at its upper end.
7. In combination with the motor of Claim 1 the tank between the boiler and
overhead condenser connected with both, and the steam pipe connecting the boiler
and tank adapted to be controlled for the purpose of feeding water to the boiler.
8. In a street car motor characterized by Claim 1 including the dry pipe extend-
ing over the elongated boiler lengthwise, the smoke pipe around the dry steam pipe,
an insulated covering surrounding the smoke pipe, registers opening through the
insulated covering into the interior of the car whereby heat may be admitted
thereto.
9. In a street car motor characterized by Claim 1, a filling valve comprising a
coupling nut, a stop valve and a check valve, the stop valve and check valve seals
being arranged adjacent to one another and their casings being adapted to be
coupled together by said coupling nut, one of said casings being carried by the
motor boiler while the other casing is carried by the charging boiler.
10. In a street car motor characterized by Claim 1, the condenser tubes open to
the outer air and having a jet opening or openings to receive the steam into the
air space to be condensed (Fig. 6).
11. In a street car motor, a condenser having head boxes coupled together with
shields for directing the air (Fig. 6ª).
Tit: 001 1
PT
1007