Improvements in Engines in which Steam or other Fluid Pressure is Transmitted from Cylinder to Cylinder to be Used Expansively.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Engines in which Steam or other Fluid Pressure is
Transmitted from Cylinder to Cylinder to be Used Expansively.
I, THOMAS WILSON, of 375, Hawthorn Avenue, Dairy Coates, Hull, in the
County of York, Locomotive Driver, do hereby declare the nature of this inven-
tion to be as follows:-
This invention relates to engines in which steam or other fluid pressure is
transmitted from cylinder to cylinder to be used expansively.
As is well known the principal obstacle against obtaining the full effect due
to using steam expansively in compound engines is resistance to the pistons by
what is termed back pressure and excessive compression, the former caused
mainly by the working pressure in one cylinder being the resisting pressure
in another cylinder, and the latter by the closing of the steam passages from one
cylinder to another.
In the case of engines designed for and worked at a constant load these diffi-
culties can be reduced to a minimum by adjusting the relative capacities of the
cylinders and the intermediate receivers; and by setting the valve motion or
point of cut off to the best advantage; but where the load is variable as in the
case of locomotive engines which are constantly working between the extreme
limits of their power, a
high expansion being essential for running at a high
speed and a full charge of steam equally essential for drawing a heavy train
up an incline the aforesaid difficulties have their maximum effect.
The essential features of my present invention will be found in the means
employed for reducing back pressure to a minimum thereby obtaining the full
effect of useful work by using the steam expansively, and limiting the com-
pression of the steam to the point at which its effect is beneficial to the smooth
and proper working of the engine.
By my said invention I provide a novel and peculiar mode of transmitting
the steam or other expansive fluid from cylinder to cylinder to be finally
exhausted into the atmosphere or condenser. I will first proceed to explain
this mode of transmitting the steam from cylinder to cylinder and for that
purpose I shall refer to the annexed drawing which illustrates by way of
diagram the cylinder and piston arrangement of a quadruple engine with the
high pressure engine crank leading the others. In the diagram, A is the high
pressure cylinder, B and C the intermediate cylinders, and D the low pressure
cylinder. The arrows indicate the movements of the pistons with the engine
going ahead, the pistons in the first and third cylinders being at half stroke:
the second and fourth pistons being each at the commencement of the stroke.
Leading up to this position, live steam has been admitted to the cylinder A
from the commencement of the stroke, the exhaust steam therefrom being
worked expansively in cylinder B. At the same time the steam just exhausted
from cylinder B has been driving the piston in cylinder C. Steam now begins
to exhaust from the driving end of cylinder A to the driving end of cylinder B

page_text: to drive the piston thereof through the next stroke. At the same time the
remainder of the steam on the other side of the high pressure piston instead of
being locked up to set up excessive compression in the high pressure cylinder
exhausts in one volume with the exhaust steam of cylinder B to work expan-
sively in cylinders C and D. The steam on the back pressure side of the pistons
in these two cylinders is waste exhaust to be discharged from both cylinders
in one volume to the atmosphere or condenser as the case may be.
It will be seen that by this arrangement undue or excessive compression of
the steam does not take place in any cylinder, but that all back pressure steam
not required for compression is exhausted from cylinder to cylinder and finally
through the exhaust port of the low pressure cylinder.
But in order to obtain a sufficiently early exhaust from the first to the second
cylinder and to maintain a continuation of pressure in the first or high pressure
cylinder A according to the load on the engine I continue to supply live steam
to this cylinder up to any required point of cut off, the additional steam so
supplied affecting in due proportion the working pressure in all the other
cylinders.
Having thus explained the nature of my invention in respect of the peculiar
action of the steam in a quadruple engine embodying my improvements I will
now proceed to describe suitable valve gear and the other mechanism concerned
in attaining this particular steam action.
Except in triple expansion engines as hereinafter explained, the high pres-
sure cylinder A is finished with two sets of admission and exhaust ports, con-
trolled by two separately worked valves, which are preferably piston valves
placed in one steam chest. One of the valves is arranged to work with a con-
stant and the other with a variable cut off. I will therefore for the sake of
distinction refer to them as the constant valve and the variable valve.
The former or constant valve is set to cut off under or at about half stroke.
To ensure this the lap of the valve at each end is more than the width of the
steam ports it controls and to have clearance sufficient to commence to exhaust
to the next cylinder B just as the piston of that cylinder is on the turn of its
stroke. The other or variable valve is arranged by means of a sector and bridle
rod as in an ordinary engine to cut off at any point. The variable valve has
its lap and clearance adjusted so that it can be set to cut off live steam at any
required point, say from 25 % to 75% of the stroke, and to exhaust into the
next cylinder at any time from the commencement or turn of the next piston.
The object and result of this arrangement which is especially important in
the case of locomotives is that steam can be graded in its expansion in the high
pressure cylinder according to the working load, providing that the steam is
discharged into the second cylinder in the following manner. On the high
pressure cylinder the two front valves exhaust through a separate passage into
a front bottom cell and the two back valves through another passage into a
back bottom cell of a four celled distributing chamber in the centre of which
chamber is placed a change valve adapted by its construction and movement
in conjunction with certain ports in the four celled chamber to conduct the
steam from the exhaust ports of the high pressure cvlinder A to the admission
ports of the low pressure cylinder Bend for end as required.
In triple expansion engines the high pressure cylinder may be provided with
one or two valves in the steam chest according to the throw of the cranks. If
only one valve is used it must be so constructed as to divide the exhausts and
have its lap adjusted to admit steam to about 70 per cent. of the stroke with
clearance sufficient to commence exhausting therefrom at about 75 per cent. of
the stroke or just as the piston in cylinder B is on the turn of its stroke.
The change valve, consisting of a plug with passages or conduits cut into it,
is reversible closing two ports and opening other two ports in the distributing
chamber according to which way the engine is to run, it being understood that
suitable mechanism is provided to change the valve which is kept tight in its

page_text: casing by a gland. The admission and exhaust ports and valve arrangement
of cylinder B may be of the ordinary type in use for the lower grade cylinders
of compound and multiple expansion engines.
But in order to exhaust the steam from the second cylinder B to the third
cylinder C, or from the third cylinder C to the fourth cylinder D) I provide an
intermediate receiver in each case preferably a cylinder in form with three
pistons working therein all on one spindle, and worked to a constant gear so
that the centre piston acts as the valve to control the exhaust from one
cylinder to the next, the said exhaust passing through a distributing chamber
as before. To ensure the proper action of the steam the valve has no lap but the
same or any required amount of clearance so that the steam is exhausted to the
next cylinder at and following the commencement or turn of the stroke, the
said valve being large enough to do all the exhausting required, a distributing
chamber directing the exhaust to the right end of the next cylinder as before.
The steam is finally exhausted through any ordinary exhaust port on the low
pressure cylinder 1), and as before explained the steam or exhaust side of the
If the exhaust
two last pistons exhausts through it in one volume of steam.
port is controlled by the usual □ valve, steam is admitted into the valve chest
from the high pressure steam chest or elsewhere to keep the valve in steam tight
contact with the port faces, and the lap is increased to prevent the admission
of such steam to the exhaust ports. If necessary as in the case of a locomotive
engine an auxiliary starting valve is provided to convey live steam to one or
more of the lower grade cylinders.
1000
G. J. CLARKSON,
Chartered Patent Agent, Stockton-on-Tees and Hull,
Agent for the Applicant.
Improvements in Engines in which Steam or other Fluid Pressure is
Transmitted from Cylinder to Cylinder to be Used Expansively.
I, THOMAS WILSON, of 375, Hawthorn Avenue, Dairy Coates, Hull, in the
County of York, Locomotive Driver, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
This invention relates to engines in which steam or other fluid pressure is
transmitted from cylinder to cylinder to be used expansively.
As is well known the principal obstacle against attaining the full effect due
to using steam expansively in compound engines is resistance to the pistons by
what is termed back pressure and excessive compression, the former caused
mainly by the working pressure in one cylinder being the resisting pressure
in another cylinder and the latter by the closing of the steam passages from one
cylinder to another.
In the case of engines designed for and worked at a constant load these diffi-
culties can be reduced to a minimum by adjusting the relative capacities of the
cylinders and the intermediate receivers: and by setting the valve motion or
point of cut off to the best advantage; but where the load is variable as in the
case of locomotive engines which are constantly working between the extreme
limits of their power, a high expansion being essential for running at a high

page_text: speed and a full charge of steam equally essential for drawing a heavy train
up an incline the aforesaid difficulties have their maximum effect.
*The essential features of my present invention will be found in the means
employed for reducing back pressure to a minimum thereby obtaining the full
effect of useful work by using the steam expansively, and limiting the com-
pression of the steam to the point at which its effect is beneficial to the smooth
and proper working of the engine.
By my said invention I provide a novel and peculiar mode of transmitting
the steam or other expansive fluid from cylinder to cylinder to be finally
exhausted into the atmosphere or condenser. I will first proceed to explain
this mode of transmitting the steam from cylinder to cylinder and for that
purpose I shall refer to Figs. 1 to 8 of the drawings, which illustrate by way
of a series of diagrams the cylinder and piston arrangement of a quadruple
engine. I shall then proceed to explain the mechanism and arrangement of
parts by which I attain this steam action by referring to the other drawings
annexed to this Complete Specification.
But it is not absolutely essential to the proper working of my invention that
the engine shall be as to its several cylinders and means for controlling the
passage of steam through them of the exact arrangement, number of cylinders
or relative capacity shown in the drawings, although that construction is in-
tended to embody a convenient arrangement both practically and for the pur-
pose of illustration, as other constructions of the engine in respect of those features
and details which effect the requisite steam action with its resultant economy
of power may be devised to suit a different throw of the cranks, or a different
number of cylinders as for instance the compound locomotive or the triple
expansion engine.
In Figs. 1 to 8, A is the high pressure cylinder, B and C the intermediate
cylinders, and D the lowest pressure cylinder of a quadruple engine in which
the steam is worked expansively according to my invention, and the aforesaid
letters are also used to denote the respective pistons of these cylinders. The
arrows indicate the movements of the pistons with the engine going ahead in
diagram Figs. 1 to 4, and with the engine reversed in diagrams 5 to 8, a cycle
of the steam action being represented each way. In all these diagrams, the
driving steam is indicated by shade lines, the open spaces being occupied by
the back pressure steam. In Fig. 1 live steam is just entering cylinder A,
and the back pressure steam is exhausting to the driving side of the piston B
and is just commencing to exhaust to the driving side of the piston C. At
this position the back pressure steam from cylinders B and C is exhausting to
the driving side of piston D, the back pressure steam in which cylinder is
exhausting to the atmosphere or condenser. This steam action continues until
the pistons reach the position shown in Fig. 2 from which position the back
pressure steam in cylinders A and B exhaust to the driving-side of piston 1)
as well continuing to exhaust to the driving side of piston C and the back
pressure steam in both cylinders C and D is exhausting to the atmosphere or
condenser. The live steam admitted to the driving side of piston A is now
admitted to the driving side of piston B, and this continues until the pistons
reach the position shown in Fig. 3, when the steam action described with
reference to Fig. 1 commences in the opposite direction and continues until
the pistons reach the position shown in Fig. 4. The steam action leading from
Fig. 2 to Fig. 3 is then repeated in the opposite direction until the pistons
again return to the position shown in Fig. 1. It will thus be seen that the
back pressure steam is never locked in any cylinder, but is continuously ex-
panded by exhaustion from cylinder to cylinder until it is eventually exhausted
to the atmosphere or condenser first from the two lowest pressure cylinders
simultaneously during part of the stroke as shown in Figs. 2 and 4 and then
from the lowest pressure cylinder only during the remainder of the stroke as
shown in Figs. 1 and 3. When the engine is reversed, the steam action is

page_text: modified in this way:-namely, instead of steam exhausting from one cylinden
to the same end of the next cylinder as shown in Figs. 1 to 4, it exhausts to the
opposite end each time as shown in Figs. 5 to 8 by means of valve mechanism
and an arrangement of steam ports, steam ways and chambers of the kind
hereinafter described.
But in order to obtain a sufficiently early exhaust from the first to the second
cylinder and to maintain a continuation of pressure in the first or high pressure
cylinder A according to the load on the engine I continue to supply live steam
to this cylinder up to any required point of cut off, the additional steam so
supplied affecting in due proportion the working pressure in all the other
cylinders.
Having thus explained the nature of my invention in respect of the peculiar
action of the steam in a quadruple engine embodying my improvements I will
now proceed to describe suitable valve gear and the other mechanism concerned
in attaining this particular steam action, and for that purpose I shall refer to
the drawings annexed to this Complete Specification in which Figs. 9 to 13
inclusive illustrate the embodiment of my said inveation in a compound loco-
motive, and Figs. 14 to 22 the modifications by which it is adapted to an engine
with triple expansion, from which examples it will be readily understood how
I adapt suitable mechanism to a quadruple or other form of engine.
Referring to Figs. 9 to 13, Fig. 9 is a longitudinal view of the high pressure
cylinder taken on line of Fig: 11 and in respect of the steam chest only of
line, of Fig. 10 to show the main admittance valves, corresponding to
which Fig. 10 is a plan view of the high and low pressure cylinders. Fig. 1
is a transverse sectional view taken on line of Fig. 10; and Fig. 12 is a
sectional plan view of the change or tap valve hereinafter described. Fig. 13
is a similar view to Fig. 9 but taken on line of Fig. 11 and in respect of
the steam chest only of line, of Fig. 10, and showing the main
exhaust valve. Fig. 14 is an enlarged longitudinal sectional view of the inter-
mediate piston valves for marine engines to be placed between the second and
third cylinders, and Fig. 15 is a transverse sectional view of a triple expansion
marine engine constructed according to my invention. Fig. 16 illustrates a
modification of my invention in which a combination of intermediate valves and
tap valves are employed between the cylinders of a triple expansion engine
and Figs. 17 to 22 are enlarged detail views hereinafter described.
Except in triple expansion engines as hereinafter explained the high pressure
cylinder A is furnished with two sets of admission and exhaust ports a¹²³ ³
Fig. 10, controlled by two separately worked valves & Figs. 9 and 13, which
are preferably piston valves placed in one steam chest. One of the valves ¹
is arranged to work with a constant and the other, 2, with a variable cut off.
I will therefore for the sake of distinction refer to them as the constant valve
and the variable valve.
The former or constant valve 1, Fig. 13, is set to cut off under or at about
half stroke. To ensure this the lap of the valve at each end is more than the
width of the steam ports it controls and is designed to have clearance sufficient
to commence to exhaust to the next cylinder B just as the piston of that
cylinder is on the turn of its streke. The other or variable valve, Fig. 9,
is arranged by means of a sector and bridle rod as in an ordinary engine to cut
off at any point. The variable valve has its lap and clearance adjusted so that
it can be set to cut off live steam at any required point, say from 25% to 75 %
of the stroke, and to exhaust into the next cylinder at any time from the com-
mencement or turn of the next piston.
The object and result of this arrangement which is especially important in
the case of locomotives is that steam can be graded in its expansion in the high
pressure cylinder according to the working load, and the supply of live steam
continued after the exhaust to the next cylinder has commenced to increase
the pressure in the other cylinder or cylinders, providing that the steam is

page_text: discharged into the second cylinder in the following manner. The valves of
the two front ports a¹² of the high pressure cylinder exhaust through separate
passages into a front bottom cell and the valves of the two back
ports through other two passages into a back bottom cell 2 of a
double celled distributing chamber in the centre of which chamber is placed
a change valve e adapted by its construction and movement in conjunction
with certain ports in the double celled chamber to conduct the steam from the
exhaust ports of the high pressure cylinder A to the admission ports of the low
pressure cylinder Bend for end as required.
In order to fully explain the internal arrangement and purpose of the dis-
tributing chamber and its tap valve I will refer to the sectional plan view
of the same as illustrated in Fig. 12 as a separate detail, and to the other sec-
tional views forming parts of Figs. 9, 11 and 13. The longitudinal sectional
view in Fig. 11 is taken on line of Fig. 12 and the transverse sectional
views in Figs. 9 and 13 on lines and respectively of Fig. 12, except
that in Fig. 12 the tap valve e is shown with the ports e¹ e² e et turned up
into view. The front exhaust port passages c¹² lead into the front cell d¹
and the back exhaust port passages into the back cell 2 of the distributing
chamber d so that all steam exhausted from the high pressure cylinder passes
through this chamber in the direction determined by the position or set of
tap valve e which is provided with four ports or steam ways c¹ e² c³ and c
placed two in line and opposite other two in line, say e¹ e opposite ce, the
cylindrical casing of the tap having of course for reversing the engine twice the
number of corresponding ports or steam ways communicating as shown with
both cells or chambers and and with chambers f¹ f2 of the steam chest f,
the partition wall of which takes the form shown in section in Fig. 12 so that
when steam ways are open they lie on opposite sides of this partition wall and
consequently lead as shown in Fig. 12 e³ e into chamber and et e² into
chamber for on the quarter turn of the tap to the position shown in Figs. 9
and 13 these steam ways lead ce into chamber f¹ and e²e into chamber f
This being the construction and arrangement of the distributing chamber d
in combination with the steam chest f it will now be seen that steam exhaust-
ing as shown in Fig. 9 from port through passage into chamber passes
in the direction of the arrow through steam way eel in the tap valve e to
chamber f escaping from this chamber through outlet g into the next cylinder
end at h¹. At the same time the steam from port a passes through passage c¹
into the cell and through the tap valve at ee as before. When the front
ports a exhaust as in Fig. 13 the steam passes through into cell d of
the distributing chamber through steam ways ²e of the tap valve into
chamber of steam chest f and through g2 to the end 2 of the next cylinder.
By turning the tap valve e to the position shown in Fig. 12 the distribution of
the steam is reversed and the front ports a¹ a² would be discharged into
chamber and escape therefrom through passage gl to the next cylinder,
but at the end thereof, whilst back ports a³ a would discharge into
chamber and outlet g to the end of the next cylinder. From this ex-
planation it will be seen how the steam from any of the exhaust ports ¹ a³a³a¹
passes into its respective cell in the distributing chamber d and from thence
In this way
to chamber for according to the position of the tap valve c.
the steam is exhausted in the manner required for the purpose of my invention
from the high pressure cylinder to the next lower grade cylinder of the series,
which in the case of a compound locomotive or ordinary compound engine is
the low pressure cylinder from which the steam is finally exhausted into the
atmosphere or condenser. What may be termed the waste steam passes from
the high pressure cylinder through the tap valve e exhausting in one volume with
the waste steam exhausted from the low pressure cylinder in the usual way.
I will now proceed to explain a convenient method of extending my inven-
tion to a triple expansion engine and for that purpose shall refer to Figs. 14

page_text: and 15, using the same letters of reference as before to indicate the same or
corresponding parts. Fig. 14 is an enlarged transverse sectional view of the
distributing chamber and the parts adjoining which are accessory to its
action. In this case the steam ports a³ ³ are used as exhaust ports only for
which purpose the valve takes the form shown in section in Fig. 14, the
position corresponding to the position of the piston in cylinder C of Fig. 2.
The ends are not essential to the action of the valve b, but are useful to
balance the steam pressure upon the valve. The construction and action of the
distributing chamber din conjunction with the tap valve e and steam chest f
is the same as already described with reference to Figs. 9 to 13 inclusive, the
object in view being to open and close the exhaust from cylinder B to cylinder C
at the right moment.
But it would be found in practice that when the cranks of a triple expansion
engine are set to angles of 120° that one valve is sufficient for the high pres-
sure cylinder although the same valve arrangement as shown more particularly
in Fig. 9 may be used. If only one valve is used it must be so constructed as
to divide the exhausts, that is, to discharge them into separate cells in the
distributing chamber d, and to have its lap adjusted to admit steam to about
55 to 70 per cent. or about two thirds of the stroke with clearance sufficient to
commence exhausting therefrom at about two thirds of the stroke or just as
the piston in cylinder B is on the turn of its stroke. What may be termed
the waste exhaust from cylinder B exhausts through the tap valve e into
cylinder C, the waste exhaust from the two cylinders exhausting in one volume
to the atmosphere or condenser.
In the case of a quadruple engine as shown in Figs. 1 to 8 the same valve is
used in conjunction with the same distributing chamber d and steam chest f,
and so on for any number of cylinders until the last or lowest grade cylinder
is reached from which the steam is exhausted in the ordinary or any suitable
way. Should the final exhaust valve be a slide or D valve, I convey steam to
the valve chamber to keep the valve tight to its seat, the valve to have its lap
increased so as not to admit live steam thereto. With a piston valve this steam
pressure external to the valve would not be required.
But this multiple expansion valve mechanism may be modified to the simpler
construction illustrated in sectional plan view in Fig. 16, as designed for a triple
expansion engine in which revolving hollow cylindrical valves are used between
the cylinders in substitution for the tap valves e herein before described.
Referring to Fig. 16, A is the high pressure cylinder, B the intermediate
cylinder and C the lowest pressure cylinder of a triple expansion engine in
which the steam is worked expansively according to my invention, and the
aforesaid letters are also used to denote the movements of the pistons with the
engine going ahead. Leading up to this position live steam has been entering
the driving side of cylinder A from the commencement of the stroke from an
ordinary variable admittance valve (not shown, but similar to the valve 72
already described with reference to Fig. 9) and from the constant high pressure
valve having the steam chest at each end external to the valve. The back
pressure steam in cylinder A has been exhausting to the driving side of the
piston B, and continues exhausting through the intermediate valve to the
driving side of the piston C. At this position the back pressure steam from
cylinders B and C is exhausting through the valve k to the atmosphere or
condenser. The live steam admitted to the driving side of piston A is now
admitted to the driving side of piston B just as it is at the commencement of
the stroke. It will thus be seen that the back pressure steam is never locked
in any cylinder but is continuously expanded by exhaustion from cylinder to
cylinder until it is eventually exhausted to the atmosphere or condenser from
the two lowest pressure cylinders simultaneously. When the engine is reversed
the steam action is modified in this way:-namely, instead of steam exhausting
from one cylinder to the same end of the next cylinder as shown in Fig. 16. it

page_text: exhausts to the opposite end each time by means of valve mechanism and an
arrangement of steam ports, steam ways and reversing mechanism of the kind
as hereinafter described.
Fig. 17 is an enlarged longitudinal sectional view of the constant high pres-
sure valve and its reversing mechanism showing the valve in the mid-position
when the engine is reversed. Fig. 18 is a corresponding plan view, and
Fig. 18 is a similar plan view partly in section. Fig. 19 is a transverse sec-
tional view taken on line 1-1 of Fig. 17 and looking to the right. Fig. 20
is an enlarged longitudinal sectional view of the intermediate valve and its
reversing mechanism showing the valve in the mid-position when the engine
is reversed. Fig. 21 is a corresponding plan view, and Fig. 21" is a similar plan
view partly in section. Fig. 22 is a transverse sectional view taken on line 2-2
of Fig. 20, and looking to the right.
Referring to Figs. 17, 18, 18 and 19, the constant high pressure valve i is
so constructed as to divide the exhausts and has its lap adjusted to admit steam
to about two thirds of the stroke with clearance sufficient to commence exhaust-
ing therefrom at about two thirds of the stroke or just as the piston in cylinder B
is on the turn of its stroke. This valve is furnished with two partition walls
extending the full length of the valve with the exception of the centre part
thereof which is furnished with a partition wall and a spiral partition wall 28.
The casing forming the centre part or main piston of this valve has two separate
steam ways passing through it one on either side of the wall or partition 2
as shown in Fig. 19, communicating with two steam ports in the back of
the valve, one steam way leading from the front to the back and the other ³
from the back to the front. When the valve is distributing steam direct from
cylinder A to cylinder B end to end as required for the engine going ahead
as shown in Fig. 16, the ports lie flush with the solid part of the steam
chest, operating no ports, but when the engine is reversed and the valve turned
to the position shown in Fig. 17, the two ports then communicate with the
ports of cylinder B and pass the steam from one end of the high pressure
cylinder to the opposite end of the succeeding cylinder as shown by the full and
dotted arrows instead of the tap valve e as herein before described with reference
to Figs. 9 to 15 inclusive. In order to reverse the engine, the valve is
mounted on or made integral with a hollow spindle 7 fitted on to the valve
spindle mand passing through the gland. This hollow spindle is made
square at and works in a correspondingly square guide attached to and
operated by a bell crank lever or arm o. This guide is flanged and externally
cylindrical to enable it to partially revolve in the bracket p by means of the bell
crank lever and gearing to turn the valve a quarter of a revolution and to hold
it in that position. The spindle rod m does not revolve, only the valve and
its connections.
Referring to Figs. 20, 21, 21 and 22, the intermediate valve j is used for
exhausting only from the cylinder B to cylinder C, and is so constructed as to
divide the exhausts, with clearance sufficient to commence exhausting just as
the piston in cylinder C is on the turn of its stroke. The centre part of this
valve is furnished with three partition walls extending the full length
of the centre part of the valve with the exception that the walls are pro-
vided with openings 18, one on either side of the valve communicating with
two steam ports ¹. The casing forming the centre part of this valve is
furnished with two separate steam ways one on either side of the wall
or partition as shown in Fig. 22. These two steam ways communicate with
the two openings and the steam ports formed in the back of the
valve, one steam way leading from the front to the back and the other
from the back to the front. When the engine is going ahead as shown in
Fig. 16, the valve distributes steam direct from cylinder B to cylinder C
end for end as required, the ports lying flush with the solid part of the
steam chest so as to operate no ports; but when the engine is reversed and the

page_text: 5
alve turned to the position shown in Fig. 20, the two ports then com
unicate with the ports of the cylinder C and pass the steam from one end of
he cylinder B to the opposite end of the cylinder C as shown by the full and
otted arrows instead of the tap valve e as herein before described. In this case
as already described with
he reversing mechanism is precisely the same
eference to Figs. 17, 18, 18 and 19.
It is obvious that the above described arrangement of valve mechanism can
be applied to quadruple expansion engines as well as compound or triple ex-
pansion engines it being only necessary to adjust the lap and clearance of the
valves to any throw of the cranks.
In the case of a triple expansion engine it is desirable to have the engine in
the forward gear always, not reversible, except in the case of emergency, on
account of not-getting the steam direct to each succeeding piston at the com-
mencement of the stroke.
Having now particularly described the nature and essence of my said inven-
tion I would have it understood that I do not limit myself to the precise details
as herein described and as illustrated in the accompanying drawings, believing
myself to be the first to propose the construction of an engine in which the
steam is passed from cylinder to cylinder in a way which enables the steam ex-
hausted from one cylinder to be used expansively in the next of the series
and without setting up back pressure in the higher grade cylinder or leaving
steam to be compressed therein, except in a very limited degree as compared
with engines of the usual or best construction hitherto is use, and that the
particular construction and arrangement of details as hereinbefore specified can
be varied in certain respects without departing from the essential features of
my invention in respect of the intended steam action.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. The arranging or combining of parts for facilitating the transmission of
steam from one cylinder to another to be used expansively without undue back
pressure or compression substantially as described and illustrated by diagrams
in Figs. 1 to 8, and embodied in the constructions illustrated in the additional
drawings annexed to this Complete Specification.
2. The combination of parts herein described in which a distributing
chamber such as d is used in conjunction with a tap or change valve such as e
and steam chest such as f for transmitting the steam exhausted from one
cylinder to the ends of the next cylinder of the series to be used expansively
therein, the several parts being arranged and operating together substantially
10 as described with reference to the accompanying drawings.
3. In the construction of compound or multiple expansion engines the use in
conjunction with each other of a constant and variable valve arrangement for
the high pressure cylinder as illustrated more especially in Fig. 10 so that the
steam can be graded in pressure in the cylinder according to the load on the
45 engine and be exhausted therefrom before being cut off to increase the pressure
in the other cylinder or cylinders in combination with the improvements
claimed in the preceding claiming clauses all substantially as hereinbefore set
forth with reference to the annexed drawings.
4. The combination of parts herein described in which in conjunction with
50 the aforesaid improved steam action a valve such as b is used as illustrated in
Fig. 14 to regulate the exhaust of steam from the second to the third cylinder
or from the third to the fourth cylinder as the case may be, substantially a
herein before described with reference to the annexed drawings, and with o
without the combined constant and variable valve arrangement as set forth i
55 Claim 3.
5. The combination of parts herein described in which in conjunction wit

page_text: the aforesaid improved steam action valve mechanism of the construction illus-
trated in Figs. 16 to 19 is used between the first and second cylinders of the
engine, and valve mechanism of the construction illustrated in Figs. 20 to 22
is used between the second and third; or third and fourth cylinders substantially
as and for the purpose herein before described.
Th
Manah 1000
G. J. CLARKSON,
Chartered Patent Agent, Stockton-on-Tees and Hull,
Agent for the Applicant.