IMPROVEMENTS IN STEAM ENGINES
Year: 1870

page_text: LETTERS PATENT to William Robert Lake, of the " " International
Patent Office," Southampton Buildings, London, Consulting
Engineer, for the Invention of "IMPROVEMENTS IN STEAM ENGINES."
-A communication from abroad by Messrs. Babcock and Wilcox,
1 TT
PROVISIONAL SPECIFICATION left by the said William Robert Lake
t.
at the Office of the Commissioners of Patents, with his Petition, on
the 5th May 1870.
4
I, WILLIAM ROBERT LAKE, of the "International Patent Office,"
Southampton Buildings, London, Consulting Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN STEAM
ENGINES," a communication; to be as follows:-
The said Invention relates to the novel arrangement of the valves of
'steam engines and means for operating the same, whereby the following.
advantages are secured, namely, independent adjustment of the induction
and exhaust valves at each end of the stroke, minimum clearance,
maximum duration of the valves and valve seats, quick opening and·

page_text: "
closing of the valves with the least practicable movement and minimum
loss of power; an automatic expansion adjusted by the governor to any
desired point of the stroke, convenience of access to all parts and facility
of handling under steam. I employ flat gridiron slide valves, one for
induction and one for eduction at either end of the cylinder, operated in
directions perpendicular to or transversely across the direction of the
motion of the piston. These valves receive an intermittent motion by
means of a series of wedge bars, adjustable relatively to each other, but
receiving their motion from an excentric in the ordinary manner. By
the adjustment of these wedge bars and this excentric, any desired
amount of "lead," "release," or "compression can be obtained. As
the motion of the valves is slight, and as they remain stationary while
closed, a small amount of power suffices to operate them without the
necessity of resorting to any means for balancing them, and the durability
of the valve surfaces is greatly increased. The aforesaid wedge bars are
carried in guides, which serve also as guides for the valve stem cross-
heads, and as drip cups for the stuffing boxes. The expansion valves
are also gridiron slide valves, and ride upon the back of the induction
valves. They are operated by means of a small steam cylinder attached
to the valve chest, the admission of steam to which is governed in point
of time to correspond with any desired position of the piston by the
automatic action of a governor, through a small piston valve. Whenever
during the stroke of the engine piston steam is admitted to this cut-off
cylinder, the expansion valve is closed with the utmost practicable
rapidity. The valve seats are all made separate from the cylinder, and
are easily removable.
⋅
Another part of the said Invention relates to the novel arrangement
of the condenser and air, pump. The condenser is arranged to form
the base of the cylinder, and to receive the exhaust steam directly
from the said cylinder, without intervening pipes or crooked passages.
The air pump is bolted to the side of this condenser, and may be operated
directly from an excentric. on the main shaft, or through levers receiving
motion from the crosshead or other moving part of the engine.
":
Another part of the said Invention relates to the crosshead. I make
this crosshead adjustable by wedges and right and left-hand screws, in
a manner which gives rigidity to the structure, avoiding the transmission
of transverse strain to the piston rod, but permitting adjustment as it

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 5th November 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the "International Patent Office," Southampton'
Buildings, London, Consulting Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of May, in the year of
our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Robert Lake, Her special licence
that I, the said William Robert Lake, my executors, administrators,
and assigns, or such others as I, the said William Robert Lake, my
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN STEAM ENGINES," a communication to me from abroad by Messrs.
Babcock and Wilcox, of Providence, Rhode Island, United States of
America, upon the condition (amongst others) that I, the said William
Robert Lake, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent..
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings forming a part of this Specification :-
The said Invention relates to the novel arrangement of the valves of
steam engines and means for operating the same, whereby the follow-
ing advantages are secured, namely:-Independent adjustment of the
induction and exhaust valves at each end of the stroke, minimum clear-
ance; maximum duration of the valves and valve seats; quick opening
and closing of the valves with the least practicable movement and
:

page_text: minimum loss of power; an automatic expansion, adjusted by the
governor to any desired point of the stroke; convenience of access to
all parts; and facility of handling under steam.
.
I employ flat gridiron slide valves, one for induction and one for
eduction; at either end of the cylinder, operated in directions perpen-
dicular to or transversely across the direction of motion of the piston.
These valves receive an intermittent motion by means of a series of
wedge bars adjustable relatively to each other, but receiving their
motion from an excentric in the ordinary manner. By the adjustment
of these wedge bars and this excentric any desired amount of "lead,"
"release," or compression can be obtained. As the motion of the
valves is slight, and as they remain stationary while closed, a small
amount of power suffices to operate them, without the necessity for
resorting to any means for "balancing" them, and the durability of
the valve surfaces is greatly increased. The aforesaid wedge bars are
carried in guides, which serve also as guides for the valve, stem, cross-
heads, and as drip cups for the stuffing boxes. The expansion valves
are also gridiron slide valves and ride upon the back of the induction
valves. They are operated by means of a small steam cylinder attached
to the valve chest, the admission of steam to which is governed in.
point of time to correspond with any desired point in the stroke of the
piston by the automatic action of a governor through a small piston
valve. Whenever during the stroke of the engine piston steam is
admitted to this cut-off cylinder. the expansion valve is closed with the
utmost practicable rapidity. The valve seats are all made séparate from
the cylinder and are easily removable,
11'
Another part of the said Invention relates to the novel arrangement:
of the condenser and air pump. The condenser is arranged to form the
base of the cylinder and to receive the exhaust steam directly from the
said cylinder without intervening pipes or crooked passages. The air
pump is bolted to the side of this condenser and may be operated
directly from an excentric on the main shaft or through levers receiving
motion from the orosshead or other moving part of the engine.
JQ
Another part of the said Invention relates to the crosshead. I make
this crosshead adjustable by wedges and right and left-hand screws in a
manner which gives rigidity to the structure, avoiding the transmission
of transverse strain to the piston rod but permitting adjustment as it
.
wears.
'

page_text: DESCRIPTION OF THE DRAWINGS.
Figure 1 is a front elevation of the engine; Figure 2 is a general
plan of the same; Figure 3 is a rear elevation of the engine; Figure.4
is a longitudinal vertical section through the cylinder and steam chest.
This Figure shews the auxiliary steam cylinder A and its connection
through stuffing boxes with the expansion' slide valves in the steam
chest c on the upper side of the main cylinder. The piston and piston
rod of the latter is also shewn, as well as the recesses for the main
exhaust valves, the valves themselves being omitted.
Figure 5 is a transverse section through the main cylinder of the
engine and shows the general arrangement of the slide valves.
Figures 6, 7, and 8 are enlarged views of the cylinder in section,
Figure 6 shewing the gridiron valve and valve seat for same; Figures 7,
and 8 show the hollow part forming the base of the cylinder, as well as
the surrounding jacket spaces of the cylinder proper, all in section.
The engine has two induction valves and two exhaust valves making.
four main slide valves in all, and each has a motion horizontally and
at right angles to the axis of the cylinder. On the back or top side of
the induction slide valves rest the cut-off or expansion valves which are:
connected by a rod parallel to the axis of the main cylinder joining
them together, the extension of which rod forms the piston rod of the
small auxiliary outside cylinder A (Figures 2, 4, and 10), which operates:
the expansion valves upon the principles set forth in the Specification
of an Invention for which Letters Patent have been obtained bearing.
date the Thirty-first day of December, A.D. 1866, No. 3452.
The action of the expansion slide valves is under the control of the
governor, and the latter regulates the points of the stroke at which
steam is admitted to the small auxiliary cylinder, in which the piston.
acting on the expansion slide works. The connection of the governor
with the expansion slide valves is shewn in Figures 1 and 2 and an
enlarged view of the details of the governor is shewn in Figure 20.
Figure 6 shows the steam chest S resting upon the top of the cylinder:
and containing the gridiron valve seats for both the main slide valve mi
and the expansion valve e resting upon it. The main valve stem is.
shewn at s.
Figure 9 shows an enlarged sectional view of one of the main valves
and its scat, similar letters refer to corresponding parts throughout the

page_text: Drawings, the remaining figures of which are herein-after described.
The four main slide valves are operated by an ordinary excentric on the
main shaft of the engine through an excentric rod provided with an eye
or hook connecting with a wrist or pin in a rocking lever as shown in
elevation Figure 3, and in plan Figure 2. This lever L is hung upon a
horizontal axis or pin p in a line with the centre of the cylinder, and the
upper and lower ends are made to connect by a wrist or joint with the
wedge bars W, which actuate the main slide valves. The rocking
lever L is provided with a socket to receive the hand lever H by which
the valves can be worked by hand when required. The wedge bars W
have a reciprocating motion and slide in fixed guides G in a line parallel
to the axis of the cylinder.
In Figure 2 W shews the wedge bars in general plan, the formation
of the guides G at the intersections of the valve stems, and the wedge
bars are more clearly shown in the enlarged views Figures 17, 18, and 19.
The motion to the valve stems and valves is given by the parallel cam
slot formed by the adjustable wedge pieces w, which are fitted and
secured into the opening o in the wedge bars W, Figures 13, 14, 15,
and 16. A pin in the end of the valve stem passes through this slot
and is preferably provided with a roller to reduce friction. By giving
proper form to these wedge pieces any desired motion can be given to
the pin in the end of the valve stem and consequently to the valves
themselves.
Figures 17, 18, and 19 are enlarged views of the end of a valve stem v
and the stuffing box v¹ for the said valve stem and also of the guides G
for the wedge bars, which guides are fashioned so as to form supports
for the valve stem crossheads and drip cups D. This construction of
wedge bars and wedge pieces enables any desired constant throw to be
given to the valves and insures uniform wear to the valve seats, and this
throw or travel is not changed in any way to suit the variable cut-off of
the expansion valves, which expansion valves themselves work with
uniform travel, and are opened and closed instantaneously by the direct
action of the steam on the auxiliary piston A which is moved at any
desired part of the stroke of the engine by the admission of steam into
the auxiliary cylinder.
The wedge bars and form of the wedge pieces which are adjustable at
pleasure, and the auxiliary expansion or cut-off valve gearing herein
described allow engines constructed on these principles to be worked with

page_text: any desired amount of "lcad," "cut-off," "release," and "compression."
The valves, moreover, after having completed their strokes remain at
rest and do not therefore consume power in being moved under great
frictional pressure. The constant but short throw of the gridiron valve
greatly prolongs the durability of the valves and valve seats.
The engine can conveniently be stopped at any desired point by
opening or closing the cut-off valve by hand, and the engine may be
warmed without danger of starting by closing the cut-off valve by hand.
In cases where it is desired to reverse the engine the starting bar may be
readily shipped or the engine handled with the same ease as if a plain
slide were used.
The crosshead shown in Figures 11 and 12 is furnished with adjustable
wedges x, x, which are provided with a right and left-handed screw Z,
one end of which projects to receive a wrench whereby the wedges
are made to expand the sliding parts of the crosshead so as to completely
provide for all wear of the piston head slides, and thereby give a proper
degree of rigidity to the structure, and also avoid the transmission of
transverse strain to the piston rod while permitting adjustment as it
Wears.
The condenser and air pump are shewn in Figures 7 and 7°. The
condenser is arranged to form the base of the cylinder and receive the
exhaust steam directly from the said cylinder without the intervention
of pipes or crooked passages. The air pump is bolted upon the side of
the condenser as shewn in Figure 7b and may be operated directly from
an excentric on the main shaft or through levers receiving motion from
any other moving part of the engine.
Having thus fully described the said Invention as communicated
to me by my foreign correspondents, I wish it understood that I
claim :-
First. The construction of the adjustable wedge bars, substantially as
shewn and described for the purpose specified.
Second. The construction of the guide pieces G forming the drip cups
D used in combination with the wedge bars.
Third. The construction of the gridiron valves for the main induction
ports of steam engines when combined with independent cut-off valves
having a constant travel and removable valve seats.
Fourth. The construction and combination of a steam cylinder and
condenser with an air pump, substantially as described and shewn.

page_text: Fifth. The construction of the crosshead with adjustable wedges and
screws, substantially as described and shewn.
Sixth. The construction and arrangement of four main slide valves
having a reciprocating motion with a constant; throw or travel at a right
angle to the axis of the steam cylinder, and operated substantially as
described.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this Fifth day of November,
in the year of our Lord One thousand eight hundred and
.seventy.
Witness,
E. C. JACKSON.
WILLIAM ROBERT LAKE. (L.S.)