Improvements in Apparatus for Exhausting the Products of Combustion from the Locomotives of Underground Railways, and Preventing the Pollution of the Atmosphere in Railway Tunnels.
Year: 1891

page_text: Date of Application, 26th Feb., 1891
Complete Specification Left, 26th Nov., 1891-Accepted, 30th Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Exhausting the Products of
Combustion from the Locomotives of Underground Railways,
and Preventing the Pollution of the Atmosphere in Railway
Tunnels.
1, CHRISTOPHER ANDERSON, of 1 Park Square, Leeds, in the County of York,
Barrister at Law, do hereby declare the nature of my said invention to be as
follows:-
The object of my invention is to effect further improvements in and relating to
a certain invention for which Alice Anderson has obtained Letters Patent
dated 26th July 1888, No. 10,851.
In carrying out my invention, I provide at the base of the engine chimney, where
it is attached to the smoke box, a door, or valve or damper, worked by a rod or
lever, or other suitable arrangement, from the foot plate of the engine, in such a
manner that the damper can be opened or closed at the will of the engine-driver,
for the purpose of allowing the products of combination to escape by the chimney,
when running in the open air, or of causing them to descend to the suction trunk,
as described in No. 10,85188, by means of a second damper placed near the bottom,
in the side of the smoke box nearest the boiler.
From this second damper I provide a pipe, preferably made of copper or sheet
brass, which leads the gases, through a gland and stuffing box, to a sliding box or
slider placed under the engine, with its open side next to the working surface of
the air trunk, as also described in 10,8518 The gland and stuffing box connection
is mounted on a diaphragm arrangement of thin steel plates, which are intended
to absorb the regular motion of the engine springs, so that the stuffing box action
will come into play only when heavy lunges of the engine take place.
The prow or part of the slider which actuates the air valves, is formed, on the
under ends of the same with the contour of a wave line, which is designed for a
speed of some practicable proportion of that of the highest speed of the engines
which are to run upon the roads, to which the invention is to be applied. This
proportion may be taken at about half.
The slide is formed of a sheet metal box of a sufficient length width and depth
for the pitch of the valves and the draught requirements of the boiler, and the
surface of the slider which, in performing its functions in contact with the working
surface of the air trunks, are made so that they can be renewed when worn out.
These surfaces may be termed the shoes of the slider.
The valves of the air trunks are made preferably of pressed steel plate, of dished
form for stiffness, and they are mounted on steel springs of the form of a truc
cantilever of uniform depth, due allowance being made for fastening both at the
root and at the point; the point being formed into a lever for resisting the shocks
of the slider prow. The whole arrangement of valve and spring is made to ensure
a good fit of the valve, nonliability to failure or sticking, and prompt action without
over action from the wave line surface of the prow and stem of the slider. The
strength of the spring is proportional to the suction of the air in the trunks, the
weight of the valve and the proportions of the wave line of the slider prow, and
sufficient to prevent the striking piece of the air valve, from leaving the surface of
the prow of the slider in passing over.
The striking piece of the air valve is formed (by preference) of pressed steel
plate, and is securely fastened to the valve dish.
The valve is prevented from falling heavily on to its seat by an air cushion, formed
of a circular or other convenient recess, in which a disc or plate of metal is made

page_text: to fit loosely, in such a manner that air is partially confined in the recess by the
action of the valve which is coupled to the cushion plate by suitable means.
The
joints, between the lengths of air trunk which form the main feature of the system,
may be made air tight by means of several kinds of expansion joint, but that which
is preferably used in carrying out this invention is formed of felt, lined or covered
flat springs which overlap the butt-joints of the trunk ends. The top joint of the
trunk is made by placing the joint springs, under the joint and inside the trunk:
the bottom joint of the trunk is made by placing the spring also under the bottom
joint, but outside the trunk, in a groove formed in the bearing chair. The top
joint spring is held in position by housing the spring ends in notches or slots, made
through the sides of the trunk ends, close under the top side of the trunks. The
side joints of the trunks are made by means of felt covered steel plates, which, in
addition to the side joints, also cover the ends of the top and bottom joint springs
and keep them in position endwise. The side plates are held to the side joints by
means of set screws and suitable brackets for carrying them. Sufficient play is
allowed in the recesses or housings in which the joint springs and plates are placed,
to admit of the joints expanding or contracting from the varying temperature of
the air trunks.
Any sediment or deposit of ash or oxide or other matter which may take place
in the air trunks, in spite of the strong current of gases which passes through them,
may be loosened by wire or other brushes of the form of balls or cylinders, or
spiked balls or teasles, or pebles or angular stones, which may be blown through the
trunks by a strong reversed current of air, and the loosened dust or matter may be
carried away at the same time to suitable traps, pits, or sumps which are provided
for the purpose of catching and retaining such solid matter.
At the end of the trunk, where the gases from the engines are exhausted by the
apparatus, a large chamber or sump, partly filled with water, is provided, for
retaining the dust which is carried in suspension by the gases, which are turned
down by the inlet pipes, so as to throw the dust into the water, and the cleared
gases are withdrawn from the chamber by the exhausting apparatus, which is thus
preserved from rapid destruction by the dust and grit carried by the gases.
Dated 26th February 1891.
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Exhausting the Products of
Combustion from the Locomotives of Underground Railways,
and Preventing the Pollution of the Atmosphere in Railway
Tunnels.
I, CHRISTOPHER ANDERSON, of 1 Park Square, Leeds, in the County of York,
Barrister at Law, do hereby declare the nature of my said invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to certain arrangements whereby the products of combustion,
as they arrive in the smoke box, are diverted from their usual course through the
funnel, and carried through a communicating pipe to a channel in the permanent
way, formed to receive the same products of combustion, which are then withdrawn
through other flues, external to the tunnel; as described in the Specification of
Letters Patent dated 26th July 1888, No. 10,851; and the object of my present
invention is to effect further improvements in such apparatus.
And in order that my said invention may be particularly described and ascertained,
reference is hereby made to the accompanying drawings, in which similar letters of
reference indicate corresponding parts.

page_text: CICTION
ROCONTOUR Ye engine, noted III
accordance with my invention.
Fig. 2 is an enlarged vertical section of one end of the sliding box.
Fig. 3 is a vertical section of a portion of the suction trunk, showing one method
of fitting the air valve.
Fig. 4 is a vertical section showing another method of fitting the air valve.
Fig. 5 is an elevation, Fig. 6 a section, and Fig. 7 a plan, showing the method
of fitting expansion joints to the air trunk, and of securing the air trunk to the
chairs.
a is the smoke box of the engine. An opening is made at & preferably about
the centre of the smoke box, and the conduit pipe e formed of sheet copper or
brass is riveted thereto. d is a sliding damper fitted to the lower end of the funnel,
just above the smoke box. e is a screen to catch ashes coming through the tubes
to the smoke box. is a sliding damper fitted to the conduit pipe c. Rotating
dampers may be substituted for sliding dampers. The dampers d and may be
opened and closed, by means of rods and levers, from the foot plate of the engine,
as shown in Fig. 1. The lower end of the pipe c passes through a stuffing box
fixed to the sliding box g. is the suction trunk, which is laid midway between
the rails of the permanent way.
The dampers d and fare used at the will of the engine driver, for the purpose of
allowing the products of combustion to escape by the ordinary funnel, when
rumming in the open air, or of causing them to descend to the suction trunk h, when
running in a tunnel.
To assist the downward action of the draught, I fit the blast pipes, leading into
the fire box, in such a manner that the nozzle may be turned downwards,
whereby the steam is directed into a funnel-shaped pipe leading into the pipe c.
The slider is rectangular in section, and is formed of slieet metal and angle
iron riveted together. The underside is perfectly level, except at the two ends g¹g',
where a wave-line form of prow is adopted for the purpose of opening the valves
without shock. The length of the prow is designed for a speed bearing some
practical proportion to the highest speed of the trains which are to run upon the
roads to which the invention is applied. The slider is made of sufficient length,
width, and depth for the pitch or distance apart of the air valves in the trunk h,
and the draught requirements of the boiler. The lower plates of the slider, which
come in contact with the working surface of the air trunk, may be renewed as they
wear out.
To enable the engine to draw the slider along the upper surface of the air
trunk h, in the manner required, brackets kk are fitted to the engine, the lower
ends of which carry a cross-bar k', at right angles to the bracket. The ends of this
cross-bar enter the looped brackets or carriers 22, fixed to the slider. y. These
carriers 2 provide for the vibration and oscillation of the engine, and prevent its
communication to the slider. The under side of the slider is open to the trunk
between the side bearing surfaces and the two ends, so that communication is
always maintained with the trunk by means of one or two valves m m, which
are held open by the slider y. These valves are shown in section in Figs. 3 and 4,
as fitted to the upper plates of the air-trunk h. The dished valve m is pressed
upwards against the opening n by the spring o. m² is a striking plate, riveted to
the valve. A central longitudinal bar forming part of the slider y, presses down
the plate mand valve m, and thereby opens the communication between the
slider g and air-trunk h. The valves m of the air trunks h are preferably made of
pressed steel plate and of circular form. The springs o raise the valves m after the
slider has passed over them. The whole arrangement of valve and spring is made
to ensure a good fit of the valve: non-liability to failure or sticking; and prompt
action.
The air valve is prevented from rising too violently to its seat by an air cushion p,
formed by a circular or other convenient recess or cylinder in which a disc or plate
of metal p² acting as a piston, is fitted. The piston p' fits the short cylinder with

page_text: sufficient freedom to enable it to fall by its own gravity, when the air valve is
depressed; the air cushion acting as a brake, when rising by the power of the
spring o. Another form of air check is shown in Fig. 4, having inlet valves to
the piston, to form a cushion or cataract against the too-speedy closing of the
valve.
The lengths of the air trunk are so fitted together as to allow for the natural
expansion and contraction of the metal. The method of connection preferred is
shown in Figs. 5, 6 and 7; but other methods may be adopted.
The joints are shown covered with plates overlapping the butt joints. The top
joint of the trunk is made by placing a plate (previously bent to a suitable curve)
under the joint and inside the trunk, with felt, asbestos, or other suitable lining,
next to the joint. The bottom joint of the trunk is made by laying the same kind
of felt-lined spring in a groove in the bearing chair, and under, but outside, the
trunk joint, with the lining s also next to the joint. The top joint spring is held in
position by housing the sprung ends in notches or slots made through the sides of
the trunk ends, close under the top sides of the trunks. The side joints of the
trunks are made by means of felt covered steel plates or springs, which, in
addition to the side joints, also cover the ends of the top and bottom joint springs
and keep them in position endwise. The side plates are held to the side joints
by means of set screws and brackets ', the latter being bolted to the side of the
trunk. Sufficient play is left in the joints and housings, in which the springs and
plates are placed, to admit of the expansion and contraction of the air trunks
arising from the varying temperature of the gases which pass through them.
For the purpose of securing the air trunks in their proper position on the bearing
chairs, conical wooden keys or wedges are used, which engage in lugs attached
to the chairs, and fitted in such a manner that the trunks are held in a central
position on the chairs ;, and also held down to the chairs; and, to prevent the keys
shaking loose between the lugs, a bolt w is provided, which passes through holes in
the keys and secures each pair of keys together.
Any sediment or deposit of ash or oxide or other matter which may take place
in the air trunks, may be loosened by wire or other brushes in the form of balls or
cylinders or spiked balls or teasles, which may be blown through the trunks by a
strong reversed current of air, and the loosened dust or matter may be carried away
at the same time to suitable traps, pits or sumps which are provided for the
purpose of catching and retaining such solid matter.
At the end of the system of air trunks, where the gases from the engines are
exhausted by the apparatus, a large chamber or sump is provided and partly filled
with water, so that the incoming gases are, by means of suitable deflectors, caused
to throw down dust or solid matter, which they carry in suspension into the water,
and thus separate matter which would otherwise be detrimental to the exhausting
apparatus.
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 is
1. In means and appliances for preventing the pollution of the atmosphere in
railway tunnels, the combination, with a locomotive engine fire box, of a conduit
pipe fitted with a damper f, or its equivalent, and connected with the sliding
box by a stuffing box, substantially as hereinbefore described, and illustrated by
the drawings.
2. In means and appliances for preventing the pollution of the atmosphere in
railway tunnels, the combination of brackets k and cross-bars ¹, fitted to the
locomotive engine, the cross-bars engaging in brackets k², for propelling the
slider and providing for oscillation, substantially as hereinbefore described, and
illustrated by the drawings.
3. In means and appliances for the purpose aforesaid, the application and use of
wave-line prows g₁ to the slider g, for the purpose of opening and closing the

page_text: valves 722 without violent shocks, substantially as hereinbefore described, and
illustrated by the drawings.
4. In means and appliances for the purposes aforesaid, the combination with the
air trunk h, of valves m, supported by springs o, and fitted with striking plates m¹;
said valves being, controlled by cataract appliances of any suitable construction,
substantially as hereinbefore described, and illustrated by the drawings.
5. In means and appliances for the purposes aforesaid, the application and use of
expansive packing, or its equivalent, to the joints of the air-trunk, substantially as
hereinbefore described, and illustrated by the drawings.
Dated 6th November 1891
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.