Improvements in and relating to High Speed Engines.
Year: 1898

page_text: Date of Application, 1st Dec., 1898
Complete Specification Left, 1st Sept., 1899-Accepted, 25th Nov., 1899
PROVISIONAL SPECIFICATION,
Improvements in and relating to High Speed Engines.
We, JOSEPH MITCHELL MCLEAN, of 69, New North Road, Huddersfield, in the
County of Yorkshire, Engineer, and ALFRED SYKES, of Springwood Street, Hud-
dersfield, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to single acting high speed engines having a cycle
similar to the "Cornish" cycle of operation, and has for its object to provide
means for effective control of the speed of rotation by an arrangement of valves
and cylinders in such a manner that the quantity of steam admitted to the first
cylinder is governed partly by increasing the compression and partly by cutting
off earlier and throttling the steam thereby giving the maximum. possible economy
of steam at all loals and governing both in the up and the down stroke at the
same time employing a simple construction. In respect to compound and mul-
tiple cylinder engines the object of the invention is to so design and arrange the
valves that the steam may be distributed simply and economically within a large
range. In accordance with the invention the arrangement is such that the ex-
pansion in a single cylinder engine is effected in two distinct stages while that
in a compound engine is effected in four, and that in a triple in six stages, so
that the range of temperature in each cylinder is reduced as also the time in
which the low temperature steam is in each cylinder, while, further according
to the invention, the valves, cylinders and receivers are so arranged as to secure
complete separation of water from the steam before the admission of the steam
to each cylinder and before compression in each cylinder, while efficient steam
jackets whose surfaces are preferably damped by the separated moisture are
provided so that loss due to initial condensation is minimized. The invention
further consists in details of construction hereafter described as applied.
In carrying the invention into effect in accordance with one design in which
the steam is expanded in four stages within a high and low pressure cylinder
respectively we provide three combined receivers and separators, the first is used
for the cover of the first stage cylinder, the second is beneath the first or high
pressure cylinder and forms the top of the second or low pressure cylinder. The
third is beneath the low pressure cylinder. This arrangement effects the jacket-
ing of the top ends of the cylinders that part of the clearance surface being large
and difficult to remove moisture from. This jacketing is rendered particularly
efficient by the superior conducting power of the separated water collected on
the upper surface. The first receiver communicates with the admission valves
of the first or high pressure cylinder. The second and third receivers communi-
cate with the lower ends of the first and second cylinders respectively by pas-
sages at the bottom of these cylinders so that the steam may find ready access
to the lower sides of the pistons on exhaust from the upper end of the cylinders.
The receivers are of moderate size so that the steam is compressed therein in
order to reduce the range of expansion in each cylinder. The exhaust from the
top ends of the cylinders takes place through an inclined or other port or ports

page_text: in the cylinder walls which are uncovered on the respective pistons reaching
the end of the stroke, the shape, area and inclination of the ports being such as
to facilitate instant rush of the exhaust steam which carries with it the separated
water. Compression and the remainder of the exhaust takes place through a
top exhaust port by the movement of the exhaust side of the steam valve.
The piston valves distributing steam to the respective cylinders are mounted
upon one spindle which is operated by an eccentric from the engine shaft.
The piston valve admitting steam to the first or high pressure cylinder is pro-
vided with. exhaust and steam edges both of helical shape corresponding to the
edge of the steam port so that on the piston valve being rotated by the opera-
tion of the governor the compression may be made to begin at practically the
beginning of the return stroke while the steam admission though also reduced
still goes on the valve being made so that the exhaust side is entirely closed
before the steani admission is stopped..
The speed of rotation is therefore decreased without throttling the exhaust
since the exhaust ports uncovered by the pistons near the end of their stroke
allow sufficient opening to exhaust. The opening to steam does not require so
much and consequently does not throttle the steam for the higher loads while
for the lower loads the steam begins to get more and more throttled after the
compression has reached maximum and one result is that at high loads the engine
is governed by cutting off and at low loads the cut off can be so arranged to give
the maximum economy which is produced by partly cutting off early and paitly
by throttling. The other advantages have been previously stated.
We preferably provide an intermediate retaining piston valve or valves for the
purpose of preventing any water contained in the steam in its passage from one
cylinder to the next from passing into the latter. The exhaust valve provided
at the lower extremity of the valve spindle is preferably double ported. Each
receiver or separator may be drained to the next receiver or separator by a pipe
connection or to a steam trap. The water in the last receiver is carried by the
exhaust steam into the air or the condenser.
The glands through which the pistons pass are provided with suitable packing
and the cylinders themselves may be provided with liners, suitably mounted
within the engine frame. while similar liners may be provided within the valve
box.
In the case of a two crank engine another line of cylinders would be added and
the valves for the two sets could be worked by a double lever deriving motion
from one eccentric provided on the engine shaft. The valve spindles and valves
may be partially balanced by means of a balance piston provided at the upper
extremity of one or other of the valve spindles. The top of the balance piston
may be arranged to compress steam in the space above it so as to prevent knock.
It is obvious that the invention is not confined to a compound engine such as
herein before described for the invention in certain features is equally applicable
to simple compound or multiple expansion engines. In the case of low speed
engines the compression of steam will prevent knock, in the provision of engines
running at a very high speeds the compression of steam may be supplemented
for the purpose of resisting knock by the provision of an air cushion cylinder.
·
1000
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to High Speed Engines.
We, JOSEPH MITCHELL MCLEAN, formerly of 69, New North Road, but now
of 53, South Street, Huddersfield, in the County of York, Engineer, and ALFRED
SYKES, of Springwood Street, Huddersfield aforesaid, Engineer, 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:--
This invention relates to single acting high speed engines having a cycle
similar to the "Cornish" cycle of operation, and has for its object to provide
means for effective control of the speed of rotation by an arrangement of valves
and cylinders in such a manner that the quantity of steam admitted to the first
cylinder is governed partly by increasing the compression and partly by cutting
off earlier and throttling the steam thereby giving the maximum possible economy
of steam at all loads and governing both in the up and the down stroke at the
same time employing a simple construction. In respect to the compound and mul-
tiple cylinder engines the object of the invention is to so design and arrange the
valves that the steam may be distributed simply and economically within a large
range. In accordance with the invention the arrangement is such that the ex-
pansion in a single cylinder engine is effected in two distinct stages while that
in a compound engine is effected in four, and that in a triple in six stages, so
that the range of temperature in each cylinder is reduced, while, further, accord-
ing to the invention, the valves, cylinders, and receivers are so arranged as to
secure separation of water from the steam before the admission of the steam to
cach cylinder and before compression in each cylinder, while efficient steam
jackets whose surfaces are preferably damped by the separated moisture are
provided so that loss due to initial condensation is minimized.
In the accompanying drawing Figure 1 represents in section a compound high
speed engine constructed according to the invention.
Figure 2 is a detail section illustrating a modification of the invention.
In carrying the invention into effect in accordance with illustrated design in
which the steam is expanded in four stages within a high and low pressure
cylinder respectively we provide three combined receivers and separators, the
first A is used for the cover of the first stage cylinder B, the second C is beneath
the first or high pressure cylinder B and forms the top of the second or low
pressure cylinder D. The third E is beneath the low pressure cylinder. This
arrangement effects the jacketting of the top ends of the cylinders that part of
the clearance surface being large and difficult to remove moisture from. This
jacketting is rendered particularly efficient by the superior conducting power of
the separated water collected on the upper surface. The first receiver A com-
municates with the admission valves F of the first or high pressure cylinder B.
The second and third receivers C, E communicate with the lower ends of the
first and second cylinders B, D respectively by passages and recesses I at the
bottom of these cylinders so that the steam may find ready access to the lower
sides of the pistons or exhaust from the upper end of the cylinders when the
pistons are in their lowest position. The receivers are of moderate size so that
the steam is compressed therein in order to reduce the range of expansion in
each cylinder. The exhaust from the top ends of the cylinders takes place
through an inclined or other port or ports or recesses I in the cylinder walls
which are uncovered on the respective pistons reaching the end of the stroke,
the shape, area, and inclination of the ports being such as to facilitate instant
rush of the exhaust steam which carries with it the condensed steam produced
by expansion and cooling of the walls. Compression and the remainder of the
exhaust takes place through the medium of a top exhaust port and the movement
of the exhaust side of the steam valve..

page_text: The piston valves F F' distributing steam to the respective cylinders by means
of passages G. and G₁ respectively are mounted upon one spindle which is
operated by an eccentric from the engine shaft.
The piston valve F admitting steam to the first or high pressure cylinder B
is provided with exhaust f¹ and steam edges f both of helical shape correspond-
ing to the edge of the steam port K so that on the piston valve being rotated
by the operation of the governor, through the rod H, the compression may be
made to begin at practically the beginning of the return stroke while the steam
admission though also reduced still goes on, the valve being made so that the
exhaust side is entirely closed before the steam admission is stopped.
The speed of rotation is therefore decreased without throttling the exhaust,
since the exhaust ports uncovered by the pistons near the end of their stroke
allow sufficient opening to exhaust. The steam does not require to be cut off
so early and consequently the steam is not throttled for the higher loads while
for the lower loads the steam begins to get more and more throttled after the
compression has reached maximum and one result is that at high loads the
engine is governed by cutting off and at low loads the cut off can be so arranged
to give the maximum economy which is produced by partly cutting off early and
partly by throttling. The amount of cushioning does not fall away at low loads
and the force required to govern is small. The other advantages have been
previously stated.
We provide an intermediate retaining piston valve L or valves for the purpose
of preventing any water contained in the steam in its passage from one cylinder
to the next from passing into the latter. The exhaust valve F2 provided at the
lower extremity of the valve spindle is (preferably) double ported. Each receiver
or separator is provided with an outlet for draining. The water in the last
reeciver is carried by the exhaust steam into the air or the condenser.
The glands through which the pistons pass are provided with suitable packing
and the cylinders themselves may be provided with liners suitably mounted
within the engine frame while similar liners may be provided within the valve
box.
The valve spindles and valves may be partially balanced by means of a balance
piston provided at the upper extremity of one or other of the valve spindles.
The top of the balance piston may he arranged to compress steam that leaks into
the
space above it so as to prevent knock.
It is obvious that the invention is not confined to a compound engine such as
herein before described for the invention in certain features is equally applic-
able to simple, compound or multiple expansion engines. In the case of low
speed engines the compression of steam will prevent knock. In the provision of
engines running at a very high speed the compression of steam may be supple-
mented for the purpose of resisting knock by the provision of an air cushion
cylinder.
It is preferable that if liners are fitted to the cylinders steam and the separated
water from the first receiver A (Figure 2) should be used for jacketting
and that the steam and water flow into a groove A¹ between the cylinder and the
liner near the top. The water will then be blown through a very small annular
space A between the liner and cylinder down on the surface of the jacket the
cylinder being recessed back below this so that the water may gather only on
the liner surface while steam is in contact with the cylinder thereby conducting
the maximum of heat through the liner and the minimum through the cylinder
to the air outside.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed, we declare that what
we claim is:
1 TL
1' 1

page_text: or receivers and the distribution and expansion of steam therein in the manner
and for the purposes herein before described.
2. In high speed engines such as hereinbefore described the provision of
receivers or separators for use also as steam jackets in the manner herein before
described.
3. A high speed engine constructed, arranged governed and operating in the
manner and for the purpose herein before described.
+000
Dated
this 1st day of september 10v.
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
18, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.