IM- PROVEMENTS IN. COMPOUND ENGINES
Year: 1878

page_text: LETTERS PATENT to Arthur Charles Henderson, of 6, Southampton Buildings,
Holborn, in the County of Middlesex, Patent Agent, for the Invention of "IM-
PROVEMENTS IN. COMPOUND ENGINES." A communication from abroad by
Alphonse Demenge, Civil Engineer, of the City of Brussels, in the Kingdom of
Belgium.
Sealed the 13th September 1878, and dated the 16th March 1878.
PROVISIONAL SPECIFICATION left by the said Arthur Charles Henderson
at the Office of the Commissioners of Patents on the 16th March 1878.
ARTHUR CHARLES HENDERSON, of 6, Southampton Buildings, Holborn, in the
County of Middlesex, Patent Agent. "IMPROVEMENTS IN COMPOUND ENGINES."
A communication from abroad by Alphonse Demenge, Civil Engineer, of the City
of Brussels, in the Kingdom of Belgium.
The machine forming the subject of the present Invention is a compound engine
or engine having two cylinders of unequal dimensions, single acting and condensing,
and is bolted to a cylindrical frame resting on a foundation.
Distribution is effected at the extremity of each cylinder by means of ordinary
slide valves governed by circular eccentrics. By this means dead space is reduced
to a minimum. Each eccentric governs two opposite slides. For this purpose the
eccentric moves in a frame to which are keyed the slide rods of the two valves
which it commands.
In order to keep the piston rods in compression, the frame, which is hermetically
closed, communicates with the condenser. To effect this hermetical closing a cylin-
drical box is used for the bearing of the main shaft, and is bolted against the frame.
In this box are three or four cushions, according to the size of the machine; to recover
the play these cushions are drawn near to the shaft by means of horizontal koys,
which are more or less locked inside the frame.
The box is covered with a movable cap furnished with a plug. The shaft
governing the distribution traverses a long socket, also closed with a plug.

page_text: Inside the frame on each side of the driving shaft are two diaphragms, serving as
supports to the cross heads of the pistons. These guides are cylindrical, and bolted
between the external diaphragms.
The cross heads of the pistons are directly connected to the crank by their
rods.
In small machines the small piston is directly acted on by the rod, and the
cylinder itself serves as guide. Lubrication of the joints of the rods is effected
by wicks hanging inside the frame, and whose upper ends, which are knotted, are at
the bottom of the reservoirs placed inside the frame.
The delivery of the oil is regulated as required by screws, which press the knots
more or less. At each passage or stroke of the rods near the wicks the oil is taken
in snuffer cups and distributed to the articulations of the rods. Lubricating the
cross heads of the pistons is effected by lubricators without the snuffer cups.
The governor screwed to the shaft is generally mounted in a pulley. The piston
of the pumps is directly governed by that of the great cylinder. This piston by the
opposite face to the rod actuates the condensing valves; the other face, which is
annular, feeds the boiler. This arrangement, which requires large plugs for large
machines, is modified as follows: On the shaft governed by the piston of the large
cylinder are two pistons, one large one for the condensing, and a small ono for
feeding; these pistons therefore move in separate cylinders, but the space comprised
between the two pistons constantly communicates with the condenser. By this
latter arrangement the pumps only work at the time of escape from the great
cylinder, which insures the compression of the rod of the large piston during its
return stroke.
The air cylinder is cast in iron with the condenser, and the feeding cylinder with
the lid of the air cylinder.
The action of the machine is very simple. The steam from the boiler enters the
small cylinder, where it partly expands; it then escapes into a heater, from whence
it enters the large cylinder to complete its expansion. The steam suitably expanded
goes to the condenser:
The advantages of the machine are,―
1. As the piston rods are always in compression the machine may be worked very
fast and so reduce their weight.
2. Because the machines are compound and single-acting there is very little
internal condensation, which is reduced to a minimum, and which saves fuel.
3. As the two cylinders are opposite it is merely the difference in the com-
pression of the rods which acts on the crank, the main shaft, and bearing.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Arthur Charles Henderson in the Great Seal Patent Office on the
16th September 1878.
ARTHUR CHARLES HENDERSON, of 6, Southampton Buildings, Holborn, in the
County of Middlesex, Patent Agent. "IMPROVEMENTS IN COMPOUND ENGINES."
A communication from abroad by Alphonse Demenge, Civil Engineer, of the City of
Brussels, in the Kingdom of Belgium.
The characteristic features of the Invention forming the subject of this application
for Letters Patent is, that the machine is a compound one, single acting, the two
cylinders composing it being in opposition.
In the accompanying Drawings, Figs. 1 and 2, at one 20th the natural size.
show two longitudinal sections of a horizontal machine, which without any material
alterations may be vertical or inclined, and non-condensing.
The frame A, Figs. 1 and 2, constantly in communication with the condensing
chamber B, is a cylinder in which the atmospheric air cannot enter by any opening.
Its lower part terminates in a support C which is bolted to the foundation stone,
and at its two extremities are fixed the steam cylinders D and E. Two openings F
and G made in the central part of the frame are destined, the first to the axle box H
and to the stuffing box I of this driving shaft J, and the second to the lid K, in the
centre of which is the socket L and the stuffing box M of the axis N of the dis-
tributer and regulator. In the interior of the frame is seen the driving crank O keyed
to the shaft J and its axle P, whose prolongation Q draws the crank R of the axis N
of the distributer. Four diaphragms S, S, S, S, cast in iron with the frame serve
to support the cylindrical guides T, T, of the piston movement.
In each guide a slide U moves, to which are separately articulated one of the
shafts V. On the upper generator of the frame are placed two simple lubri-
cators W, W, for greasing the guides T, T, and a third grease box X for the three
articulators of the shafts V, V. All these lubricators are vases communicating with
the atmosphere, and whose bottoms are pierced with holes in which the grease
wicks Y, Y, Y, pass. These wicks, free at their lower ends, are knotted at the other
end; on each knot a pressing spring Z rests, whose object is to regulate the delivery
of each grease box.
The triple greaser X has three pendent wicks, the drops of grease which are at
their lower ends are at each turn of the machine taken by the cups a with snuffers b,
and thence conducted by means of tubes c, c, to the axles to be greased.
The lubricators W, W, do not require snuffers; tubes d, d, conduct the oil which
escapes to the guides T, T.
The cushion of the driving shaft is greased in the same way as the guides, with
the difference that the tubes conducting the oil are suppressed. As to the shaft N
of the distributer it is lubricated by an ordinary wick greaser.
The shafts V, V, in cast iron are by their cross heads e, e, articulated to the same
axle P; by this means each bead has only one cushion f. This is arrived at
by arranging so that the shafts are always compressed. Nevertheless as it
happens that after the closing of the tap for taking in steam the machine still
makes some turns, during some of which the shafts are feebly held in tension,
their cross heads are united by aid of two iron pieces g,g, in
glass.
form of an eye-
In order to know if the triple greaser is working properly two sights (not
shown in the Drawing, as they are at the anterior part of the frame) admit of
examining if the snuffers b, b, b, are at each revolution grasping the wicks Y, Y, Y.
The axle box H, of which a horizontal section, Fig. 6, is seen, is turned internally
and bolted to the frame. In the interior are four cushions h, h, h, h, between which
the shaft J turns; these cushions are brought near to the shaft by means of four
keys i, i, by the intermediary of four wedges j,j; these keys, are brought back from

page_text: the interior, and when the screwing is effected the whole is covered with a cap,
which bears the stuffing box I.
In each steam cylinder is a piston k, l, the shaft of which cast in iron with it is
keyed to the slide u. Nevertheless when the cylinder is too small the piston is
firmly articulated directly to the shaft V. In order to reduce as much as possible
the internal condensations, the pistons as well as the bottoms of the cylinders have
their parts in contact with the steam lined with lead m, m.
Distribution is effected by slide valves of some sort, but the steam boxes 1, 0, are
placed at the ends of the cylinders so that the dead spaces may be reduced to a
minimum.
In accordance with the distribution supplied to the machine it can work at
.determined or variable expansion by regulator or by hand. The parts of this latter
action are shown, Fig 2; it will be seen to constitute a Meyer expansion, with
this principal difference, that to vary the introduction of steam the shaft P which
traverses the stuffing box q does not turn by itself.
For the large cylinder, the volume of introduction not varying, the same dis-
tributer is used as for the small cylinder, but it is much more simple.
The government of the two distributers is made by two eccentrics 7, 8, cast
together; the eccentric r governs the slide valves t, t, and that s the expansion
plates u, u.
The two rods of the slide, valves t, t, are keyed to the same eccentric frame v, and
the two shafts of the plates u, u, to a second frame w. Each frame (Figs. 2 and 7)
is of U shape, and is guided by a shaft y which is fixed to the frame and which
slides in two guides 2, %, bolted to the frame of the machine. Each eccentric rubs
against two cushions A¹, A¹, which can be brought against it by aid of wedges B', B',
by means of keys C', C. This arrangement has the advantage that when one takes
care to wind each key evenly the wear of the cushions cannot lead to any perturba-
tion of the distributer.
Each frame being of a single piece its lower part is hollowed in the shape of
a trough, and contains the oil intended to lubricate the eccentrics and their
cushions.
The regulator is in a small pulley D¹ screwed to the shaft of the machine. This
pulley consists of two parts, united one with the other by a certain number of
screws; the plate E¹ and the globe F', the central blocks G¹, G¹, submitted to the
action of centrifugal force, are articulated to the plate E, their irregular forms
conduce to what is desired, and are as heavy as possible so as to have a regulator of
the utmost power in a small compass.
A lever H cast in iron with each block G¹
engages by its extremity H' in an opening I¹ made in the movable axis J' and rests
on a steel hoop K¹ placed in this opening.
.
The axis J' guided in the plate and globe is in bronze, it is always in compression,
and its external extremity L', terminating in a steel point, rests or props against
the breech of a small cannon, whose trunnions are articulated to the lever o¹ of
the balance weight, which equipoises the action of the centrifugal force on the
two central blocks. This regulator is highly sensitive, and its action may, as
near as is desired, become isochronous. The lever o' bears a horizontal arm P¹
whose extremity governs the valve Q¹. The condenser R¹ (Figs. and 2) has
the form of a vertical cylinder; it is cast in a single piece with the air pump S¹,
and has only one valve T¹, which is lodged in the ball U₁. Condensing is effected in
the chamber V', where the escape steam by the double valve W¹ and the cold water
in a conical jet arrives under the valve X, which can be raised more or less. The
piston Y' of the air pump is connected to the great piston 1 by the shaft Z'.
The air cylinder is pierced with two square holes a' destined to maintain the
part to the left of the piston Y¹ constantly in communication with the condensing
chamber; two other openings b¹, but circular, are alternately masked and unmasked
by the piston.
The following is the mode of action of the air pump:-When the piston Y' makes
the right to left stroke, a vacuum is first produced behind it; then it unmasks the

page_text: openings b', 6', and the water and air flow into the right side of the air cylinder; so
things continue until the piston is at the end of its course. When it returns towards
the right it commences to force the air and water in the condenser, but the moment
the orifices b', 6', are completely masked, first the forcing of the air which is to the
right of the piston takes place by the valve T', then when all the air is evacuated
the forcing of the water commences by the same valve.
As will be seen the left part of the piston effects nothing, and the right only forces
the air during a quarter turn. It is on account of this peculiarity that the condenser
does not require much work till during the second part of the retrograde movement
of the great piston 7, that is to say, when it is necessary to create a resistance to the
motion of the latter sufficiently great to extinguish its vis viva and maintain its
shaft in compression. This condenser therefore is specially applicable to full-speed
inachines on account of the suppression of suction valves, and to single-acting
machines on account of the distribution of its work.
When the machine should work without condensing one should have recourse to
the steam cylinder, Fig. 3. Then to keep the shaft of the large piston Z always
constantly compressed during its whole retrograde movement, the resistance arising
from condensation is replaced by that due to the action of the steam which is in the
small cylinder c¹. This small cylinder, cast in iron with the lid d', is in permanent
communication with the supply pipe by the tube e¹. In the cylinder c¹ moves a
piston f¹ cast in iron with the great piston 7.
The cylinder c¹ instead of being a steam one may also be an air one; then its
orifice g' will no longer be at the end of the cylinder, but towards the centre, so that
the air is compressed during the last part of its retrograde movement and thus
serves to annihilate the vis viva of the great piston and its gear. This latter
arrangement is especially applicable when the machine is arranged vertically. The
following description illustrates the working of the machine-The steam arrives
from the boiler by the pipe h' (Fig. 8), and encounters a purifying case, where it is
freed from the water it may contain in excess; then it presents itself in the small
cylinder D, after having passed the valve and the steam entry tap j'. Working
at full pressure and effective expansion in the small cylinder the steam passes by
the pipe into the heater l'.
The large cylinder E is fed (during part of the direct movement of its piston) by
the heater, with which it communicates by the pipe m¹, after which the steam
which has been admitted there completes its expansion, and finally enters either in
the condenser R' or into the atmosphere, according to the disposition of the double-
valve W. The heater which is placed below the case i communicates with the
lower part of the latter by the tube n³, and with the bottom of the envelope by the
tube o. Thus all the purge and internal condensed waters unite at the lower
part of the heater, where they are taken by a special pump, to be forced in the
boilers.
The case may likewise be put in communication with the box of the great cylinder,
and afterwards with the internal reservoir of the heater by means of the tube p¹ and
tap q', which is opened either at starting or when exceptionally increasing the,
power of the machine.
Between the fly and the end pedestal of the driving shaft is an eccentric which
governs the double feed pump (Figs. 4 and 5). The two bodies r and a' of this
pump are vertical below the heater, and constructed on the same principle as the
air pump, that is to say, without suction valves.
The pump s' is intended to constantly remove all the water in the heater and to
force it in the boilers; the pump r¹ takes in the ball U¹ above the valve T', the rest
of the water necessary for alimentation; this completion of water is regulated by
means of a tap on the ball U². The pumps 7 and 8' are of unequal sections but
similarly constructed.
In Fig. 4, which is a vertical section of the pump ³, a window t¹ is shown by.
which the tepid water penetrates the body of the pump when its piston u' completes

page_text: its ascensional movement and commences its descent. Near the middle of this latter
the window t¹ is masked, and the water pressed by the piston raises the valve u¹¹
and is forced by the tube v¹ in the boilers. These two pumps have distinct suction
tubes and forcing valves, but above the valves the waters mix in the chamber a¹ and
are forced together by the tube v¹.
The advantage of this double pump is its great simplicity, its certain action, and
great saving of fuel by introducing the purge and condensing water into the boilers.
When these latter are below the heater the pump s' may be dispensed with, using
only an ordinary feed pump.
The advantages presented may be thus numerically estimated :-
1st. That the shafts are always in compression, and that the frictional surfaces are
very extended and perfectly greased. The machine may be made to make a number
of revolutions, and consequently render it compact, light, and less expensive.
2nd. Internal condensation is reduced to a minimum as the machine is compound.
It has only one blow-out per revolution, which reduces to a minimum the product
of the surface, which limits the volume of steam expanded by the numbers of blows
out per revolution, that in increasing the velocity the duration of the successive
coolings and heatings are diminished, and consequently the quantity of steam which
each stroke condenses to heat the internal side of the great cylinder, that the pistons
and bottoms of the cylinders are provided with some slight conducting lining, and
that the intermediate reservoir and great cylinder are reheated.
3rd. That there are two distributing boxes; the steam escapes are diminished,
and, moreover, attenuated, because the steam that escapes by the slide valve of a
cylinder is not lost for the other.
4th. Dead space is greatly reduced, and the use of an intermediate reservoir
between the cylinders admits, with a good distribution, of drawing from the steam
its maximum force.
5th. Because the two shafts are in opposition it is simply the difference of their
compressions which causes the retrocession of the crank axle, and the crank stays
the driving shaft, rests on the main pedestal, tends to dislocate the foundation, and
so on, which admits of reducing the principal parts whilst obtaining a better
working of the machine.
6th. The regulator is simple, very sensitive, and capable of an action as near as
possible approaching isochronism.
7th. The condenser being of extreme simplicity admits of producing an excellent
vacuum, since there are no suction valves and very few joints.
-
8th. The purge pump of the reheater gives place to a saving of fuel.
9th. The hermetical closing of the frames of the condensing machines free the
piston from atmospheric pressure and air admissions which might result therefrom.
10th. The presence of guides in large machines. insures the duration of these
organs and of their cylinders.
1
Finally, what is claimed as the Invention is,--
1st. The general form of the machine, which is compound and single acting, with
opposite cylinders.
2nd. The particular shape of the frame, which is that of a closed cylinder, at whose
ends the two cylinders are bolted.
3rd. The use of piston guides, supported by bored diaphragms.
4th. The cylindrical axle box bearing the pedestal. with horizontal wedges.
5th. The method of greasing with knots, the supply being regulated at will.
6th. The mode of joining the cross heads of the shafts by pieces of iron of spectacle
form.
7th. The use of lead lining for the pistons and bottoms of the cylinders.
8th. The pistons cast in iron, with their rods.
9th. The disposition of expansion, which when the introduction of steam is varied
does not occasion a rotation of the shaft governing the expansion plate.
.. 10th. The U shaped form of the eccentric frames in conjunction with. their details.

page_text: 11th. The pulley regulator.
12th. The form of the condenser, and the mode of action of its air pump,
which has a single valve, and only conveys power to the machine during a
quarter revolution.
13th. The small inert cylinder by which the rod of the great piston in non-
condensing machines is held in compression.
14th. The double feed pump.
15th. All the applications to which this machine may be put.
In witness whereof, I, the said Arthur Charles Henderson, have hereunto
set my hand and seal, this Sixteenth day of September, in the year of
our Lord One thousand eight hundred and seventy-eight.
A. C. HENDERSON. (L.S.)