Year: 1887

page_text: We, WILLIAM YOUNG FLEMING, and PETER FERGUSON, both of Phoenix Works,
Paisley, in the County of Renfrew Engineers and Shipbuilders 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:-
Our invention relates to improved arrangements of multiple expansion steam engines
wherein four or more cylinders placed parallel to each other are so connected to two
or more cranks that proper balancing of the working parts and compactness of design
are insured while in general obviating the disadvantages incident to the use of the
tandem arrangement of cylinders.
In multiple expansion engines having four cylinders into each of which the steam is
admitted in succession we may either group the cylinders around a valve casing
common to all the cylinders or provide separate valve casings for each pair of
cylinders and we connect the cylinders in pairs to two cranks in line or opposite each
other on the crank shaft through connecting rods of T-shape or triangular or similar
form, the cylinders for the first and third stages of expansion being generally placed
on opposite sides of the crank shaft and connected to one crank and those for the
second and fourth stages of expansion similarly placed and connected to the second
crank, dead centres in the throw of the crank being avoided.
In the case of triple expansion engines we employ four cylinders two of which are
placed on one side of the shaft and may be of the same diameter while the high pressure
and intermediate cylinders are placed on the opposite side of the shaft and one of the
two low pressure cylinders connected to each through a triangular connecting rod to
act on the corresponding crank.

page_text: When a greater number of cylinders are employed they may be placed on each side
of two cranks or two cylinders may be connected to each of three or more cranks
through T-shaped connecting rods, the centre of the rod being suitably guided in each
case; or, one, two or more of the cylinders may be placed over others tandem-
wise the piston rods being connected in pairs to each crank in the manner above
mentioned.
The like arrangement of multiple expansion engines is particularly applicable to
disconnecting and twin screw or paddle steamers in which case the cylinders are
connected in pairs to one or more cranks on each shaft; and while in driving the
screw or paddle shafts in unison the steam is successively expanded into the several
cylinders of the engines connected to both shafts, a separate connection to the steam
supply is provided to admit steam direct to the set of cylinders connected to each shaft
when the engines are disconnected and actuate the shafts independently. Multiple
expansion engines of the kind referred to may also under our invention be made single
acting.
In the accompanying drawings which in part illustrate our invention, figure 1 is an
end elevation, and figure 2 a horizontal section of a quadruple expansion engine in
which the steam is successively expanded through the cylinders 1, 2, 3 and 4 and
finally discharged into the condenser 5. The piston rods 6 and 7 of the cylinders 1
and 3, are connected to a triangular or T-shaped connecting rod 8, whose lower end
engages the crank 9, and the piston rods of the cylinders 3 and 4, are in like manner
connected to a T-shaped connecting rod 10, acting on the crank 11, the cranks 9 and 11,
being in line on opposite sides of the crank shaft 12. The pump levers 13 are
connected to centre pins 14 on the connecting rods 8 and 10 and serve as radius rods
to guide the connecting rods in whose upper ends pins 15 are fitted to work in slide
blocks in slots 16 in the piston rod ends, but short links may be employed to connect
the connecting rod ends with the piston rod ends. Steam from the pipe 17 is admitted
to each cylinder 1, 2, 3, 4 in succession through piston valves or other valves working
in a casing 18, the steam used in the cylinder 1, being exhausted, through the valve
casing into the cylinder 2 and thence consecutively through the cylinders 3 and 4, and
the exhaust steam from the last cylinder passes to the condenser 5.
In figure 3, is shown an arrangement of quadruple expansion engines similar to
that shown in figures 1 and 2, but with separate valve casings 18 and 19 for the pairs
of cylinders on opposite sides of the crank shafts. In this case the steam admitted to
the cylinder 1 is exhausted through the valve casing 18 to the cylinder 2, thence
to the valve casing 19, and in like manner through the cylinders 3 and 4 to the
condenser.
In figure 4 is shown an arrangement of four cylinder triple expansion engines in
which two low pressure cylinders 3, 3, of equal size placed on one side of the crank
shaft cooperate each with one of the cylinders 1, 2, on the opposite side of the crank
shaft in driving cranks through triangular connecting rods. In this case steam
admitted by the pipe 17, to the valve casing 18, passes to the cylinder 1 is then
exhausted through the valve casing to the cylinder 2, and thence through the
valve casing is exhausted simultaneously into the cylinders 3, 3, the piston of one of
which cylinders is driven upwards while the other is driven downwards.
The diagram figure 5, represents in plan a four cylinder triple expansion engine
similar to that shown at figure 4, but having two high pressure cylinders 1, 1, of small
size, an intermediate cylinder 2, into which both of the cylinders 1, 1, exhaust through
the valve casing 18, and a low pressure cylinder 3, to which the steam exhausted from
the cylinder 2 through the casing 18, is expanded. One of the high pressure
cylinders 1, cooperates with the cylinder 2, and the other with the cylinder 3, to
actuate the respective cranks 9 and 11 on the shaft 12. In figure 6 is represented a
like arrangement of triple expansion engine in which there is one high pressure
cylinder 1, two intermediate cylinders 2, 2, and a low pressure cylinder 3. One of the
intermediate cylinders 2 operates in connection with the high pressure cylinder 1, and
the other in connection with the low pressure cylinder 3, the steam from the

page_text: cylinder 1 being exhausted through the valve casing 18 to both intermediate
cylinders 2, 2, and thence to the cylinder 3. The cranks connected to each pair
of cylinders being in line on opposite sides of the centre of the crank shaft, the valves.
should be arranged to direct the steam to the upper side of the pistons of the cylinders
connected to one crank and to the lower side of the pistons of the cylinders connected
to the other crank.
Figure 7 represents in plan an arrangement of quadruple expansion engine adapted
for driving the propeller shafts of a twin screw steamer. The high pressure cylinder 1,
and intermediate cylinder 2, are connected to a crank 9 on one shaft 12 and the
intermediate cylinder 3 and low pressure cylinder 4 to a crank 11 on the shaft 12 a.
Figures 8 and 9 are respectively a sectional elevation and plan of quadruple expansion
engines for twin screw steamers the arrangement being similar to that shown at
figure 7, excepting that, instead of one pair of cylinders being placed forward of the
other, as indicated in that figure, to provide for cases in which the shafts are comparatively
close together, the cylinders are placed abreast.
In each of the examples shown at figures 7 and 8, 9, the screw shafts 12 and 12 a,
may be driven simultaneously the steain being passed successively through the series
of cylinders 1, 2, 3, 4, or the shafts may be actuated independently in which latter
case the connection between the cylinders 2 and 3 is shut off and the cylinder 3,
supplied with steam from the boiler through a reducing valve. The steam from
the cylinder 2 may then be exhausted either to the atmosphere or to the condenser 5.
Figures 10 and 11 are respectively a sectional elevation and plan of an arrangement
of quadruple expansion engines adapted for driving a paddle steamer. The general
arrangement is similar to that shown in figures 1 and 2, excepting that the engines are
inverted, and the piston rods are guided in slide guides 21 and connected to the
pins 15, on the ends of the T-shaped connecting rods by links 22, while the centre
pins 14 of the connecting rods move in guides 23 in lieu of being guided by radius
rods. Any of the usual devices whereby the cranks are disconnected may be employed
so that the coupled cylinders 1, 3 and 2, 4 may act as independent engines, steam
being supplied to the cylinders in the manner described with reference to the mode of
working the screw shaft engines shown at figures 7, 8 and 9.
When the engines are not intended to be worked independently the order in which
the cylinders 1, 2, 3, 4 are coupled to the cranks in the engines shown at figures 7, 8,
9, 10 and 11, may be varied in any of the ways hereinbe fore indicated with reference
to figures 1 to 6, and either three or four stages of expansion may be employed.
In some cases also additional cylinders may be mounted tandemwise upon any
or all of the cylinders 1, 2, 3, 4 of the various arrangements described and connectedl
to give a correspondingly increased number of stages of expansion of steam.
Figures 12 and 13 are sectional side and end elevations and figure 14 a plan of a
single acting high speed engine as constructed in accordance with our invention.
This arrangement is adapted for quadruple expansion of the steam which is admitted
to the cylinders 1, 2, 3, 4 in the order of their numbers but only on the upper sides of
the several pistons the bottom of the cylinders being open to a steam tight casing 24,
in which the crank shaft works and out of which it is carried through stuffing boxes 25.
The connecting rods 8, 10 are directly connected to the piston rods and the centre
pins 14 are guided by radius rods 13.
Figure 15 shows a triple expansion single acting engine arranged in a similar
manner.
Having now particularly described and ascertained the nature of our said invention,
and in what manner the same is to be performed, I declare that what I claim is :-
1. In multiple expansion steam engines the arrangement of four or more cylinders
placed parallel to each other on opposite sides of a crank shaft or shafts and connected
in pairs by triangular, T-shaped or similar connecting rods to the crank shaft or shafts,
substantially as herein described.
2. The several arrangements of multiple expansion steam engines hereinbefore
described with reference to figures 1 to 6, of the annexod drawings.

page_text: 3. The arrangements of disconnecting multiple expansion engines for actuating
screw propeller shafts, substantially as herein described with reference to figures 7, 8
and 9, of the annexed drawings.
4. The arrangements of disconnecting multiple expansion engines for actuating
paddle shafts of steamers, substantially as herein described with reference to figures 10
and 11 of the annexed drawings.
5. The arrangements of single acting multiple expansion engines herein described
with reference to figures 12, 13, 14 and 15 of the annexed drawings.
Dated this Wightnanth low of February 1887
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow,
Agents.