IMPROVEMENTS IN AND APPARATUS FOR GOVERNING STEAM ENGINES
Year: 1878

page_text: LETTERS PATENT to William Dawes, of Kingston Grove, Leeds, in the County
of York, Engineer, for the Invention of "IMPROVEMENTS IN AND APPARATUS
FOR GOVERNING STEAM ENGINES."
Sealed the 13th May 1879, and dated the 18th November 1878.
PROVISIONAL SPECIFICATION left by the said William Dawes at the Office
of the Commissioners of Patents on the 18th November 1878.
WILLIAM DAWES, of Kingston Grove, Leeds, in the County of York, Engineer.
"IMPROVEMENTS IN AND APPARATUS FOR GOVERNING STEAM ENGINES."
وو
The object of this Invention is to provide a simple, direct, and efficient
"automatic " or "governable" expansion gear for slide valve engines, specially
arranged and constructed to overcome in a less complicated and more direct manner
the heretofore great difficulty found in actuating such gear, namely, a "coupled up
automatic slide valve expansion gear, without having to substitute larger and more
powerful governors than those used with the ordinary "throttle valve" method or
system of governing.
.
It has before-time been found necessary to employ an intervening or auxiliary
power to effect the above object, and various methods have been devised for the
purpose, the most usual being hydraulic pressure from over-head cisterns, or some
other extraneous or independent source; or, when such may not be available, the
use of water or other liquid as the steadying or controlling medium, and steam
pressure to give the necessary power to the same; whereas, in the gear or gears I
am about to describe, I employ the hydraulic pressure and power combined, which
must of necessity be always present and available in every steam engine, namely,
the "feed" or boiler water and pressure taken from any convenient part or source
of or in the same; for instance, where an "air vessel" is or can readily be attached,
I obtain my supply and pressure (power) at or near the "feed pump," as the most
convenient point; or, in other cases, at or near the entrance of the " feed pipe," to

page_text: the boiler itself, and by this simple means I obtain the solid or "non-elastic "
pressure and power required, and that always available, and requiring less compli-
cation in the mechanical arrangements and details.
Having described the source from which I derive the auxiliary power to effect
for or in lieu of the governor the changes in the gear and the "cut-off" valve or
valves as required by the controlling power or influence of the governor, I will
now describe the main features of peculiarity in the gears I prefer to employ in
transmitting or utilizing this power.
cut-
First, then, to avoid complexity and obtain directness and rapidity of action, I
place the machine or apparatus which constitutes the gear proper upon the ".
off" or expansion valve rod immediately outside the "valve-chest," between it and
the fixed guide; and I prefer to construct this with a pair of parallel cylinders
with pistons or plungers, acting in a longitudinal or parallel direction as regards
the said rod, each piston or plunger being coupled direct to one of a pair of cut-off
or expansion valves, the hydraulic ("feed water") pressure being behind or upon
the two pistons or plungers, and their relative as well as total or definite length,
distance, or position being maintained by a lever or other equivalent action, and
thus a simple and perfectly "direct acting" gear and connection are obtained.
"In those cases where, from want of room or other cause, the above mechanical
arrangement may not be desirable I substitute the "right and left hand or reversed
screw action to the rod and valves, and I place upon or in direct connection with
the cut-off valve rod, in lieu of the before-described double cylinder arrangement,
a rotary hydraulic motor, to give, also in a direct manner, the necessary revolving
motion to the rod and screws, and through them make the necessary changes for
governing in the cut-off valves themselves.
"
Although I prefer to place my hydraulic motor, whichever or whatever it may
be, upon the cut-off valve rod, to avoid complexity and render the gear and action
direct and rapid, I do not confine myself to that arrangement, but sometimes employ
the feed or boiler water pressure and power, as herein before explained, through any
convenient motor fixed to some stationary part of the engine; and in this case I
make the necessary connection with the rod and valves through the "working
parts or details in lieu of a pair of elastic tubes, which in the former arrange-
ments are all that is necessary to convey the hydraulic power from the governing
valve which is actuated by the governor to the travelling motor or gear.
"
"
"
To render the duty required from the governor as light and easy as possible, I
construct the said controlling or governing valve as a "relieved" or equilibrium
valve, and also in such a manner that the "back pressure" shall not force it away
from its "seat-face."

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Dawes in the Great Seal Patent Office on the 17th May
1879.
WILLIAM DAWES, of Kingston Grove, Leeds, in the County of York, Engineer.
"IMPROVEMENTS IN AND APPARATUS FOR GOVERNING STEAM ENGINES."
"
The object of this Invention is to provide a simple, direct, and efficient automatic
or governable expansion gear for slide valve engines, specially arranged and con-
structed to overcome in a less complicated and more direct manner the heretofore
great difficulty found in actuating such gear, namely, a 'coupled up' automatic
slide valve expansion gear, without having to substitute larger and more powerful
governors than those used with the ordinary "throttle valve" method or system of
governing.
It has before-time been found necessary to employ an intervening or auxiliary
power to effect the above object, and various methods have been devised for the
purpose, the most usual being hydraulic pressure from over-head cisterns or some
other extraneous or independent source; or, when such may not be available, the
use of water or other liquid as the steadying or controlling medium, and steam
pressure to give the necessary power to the same; whereas in the gear or gears I
am about to describe I employ the hydraulic pressure and power combined, which
must of necessity be always present and available in every steam engine, namely,
the "feed" or boiler water and pressure taken from any convenient part or source
of or in the same; for instance, where an "air vessel" is or can readily be attached,
I obtain my supply and pressure (power) at or near the "feed pump," as the most
convenient point, or, in other cases, at or near the entrance of the feed pipe to the
boiler itself; and by this simple, means I obtain the "solid" or non-elastic pressure
and power required, and that always available, and requiring less complication in
the mechanical arrangements and details.
Having described the source from which I derive the auxiliary power to effect
for or in lieu of the governor the changes in the gear and the "cut off" valve or
valves as required by the controlling power or influence of the governor, I will
now describe the main features of peculiarity in the gears I prefer to employ in
transmitting or utilizing this power.
First, then, to avoid complexity and obtain directnes; and rapidity of action, I
place the machine or apparatus which constitutes the gear proper upon the cut-off
or expansion valve rod immediately outside the valve-chest, between it and the
fixed guide of the rod; and I prefer to construct this with either one or a pair of
parallel cylinders, with pistons or plungers acting in a longitudinal or parallel
direction as regards the said rod, each piston or plunger being coupled direct to
one of a pair of cut-off or expansion valves, the hydraulic (feed water) pressure
being or "acting" upon the said pistons or plungers, and their relative as well as
total or definite length, distance, or position being maintained by a lever or other
equivalent action; and thus a simple and perfectly "direct acting" gear and con-
nection are obtained.
In those cases where, from want of length or room or other cause, the above
arrangement may not be desirable, I substitute the " right and left hand" or
reversed screw action to the rod and valves, and I place upon or in direct con-
nection with the cut-off valve rod outside the steam-chest, and in lieu of the before-
described cylinder and piston arrangement, a "rotary" hydraulic motor, to give, also
in a direct manner, the necessary revolving motion to the rod and screws, and
through them effect the necessary changes for governing in the cut-off valves
themselves.
Although I prefer, except in special cases, to place the hydraulic motor, whichever
or whatever it may be, upon the cut-off or expansion valve rod, to avoid complexity
and render the gear and action direct and rapid, I do not confine myself to that
feature or arrangement, but sometimes employ the feed or boiler water pressure and

page_text: power, as herein before explained, through any convenient motor fixed to some
stationary part of the engine; and in this case I make the necessary connection
between it and the rod and valves, by slides, links, or other mechanical means in
lieu of a pair of flexible or elastic tubes, which in the former arrangements with
the moving or travelling" motors are all that is necessary to convey the hydraulic
power from the small leading or governing valve which is actuated by the
governor to the said travelling motors or gear. To render the duty required
from the governor as light and easy as possible, I generally construct the said
controlling or governing valve as a "relieved" or equilibrium valve, and also
in such a manner that the back pressure shall not force it away from its seat and
face.
In the accompanying illustrations, Figure 1 is an elevation of the first described
gear and valves; Figure 2 is a section of the cylinders of the same; Figure 3 is an
end view of the cylinders without covers; Figure 4 is a side or edge view of one of
the cut-off valves; Figure 5 is a side or cross elevation showing the positions of
the gear, the main valve rod, and the small governing valve; and Figure 6 is an
elevation of the gear when the rotary motor and double screw are employed.
Having now described and particularly ascertained the nature of the said Inven-
tion, and the manner in which the same is or may be used or carried into effect, I
wish it to be understood that I do not confine or restrict myself to the precise
details or arrangements which I have described or referred to, as many modifica-
tions and variations may be made therefrom without deviating from the principles
or main features of the said Invention; but what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. The appropriation or employment of the feed or boiler water for actuating
hydraulic expansion gears, for the purpose of obtaining from one reliable source
both the pressure for power and the solidity for controlling or rendering the action
definite and certain, as herein-before explained.
Secondly. The fixing or attaching of the hydraulic gear to or upon the cut-off
valve rod or other convenient or equivalent part of the valve gear, for the purpose
of simplifying the action, and rendering it direct, prompt, and certain.
Thirdly. The employment of either the "double cylinder" or the rotary motor as
described or stationary, for the purpose of actuating a pair of cut-off valves, in con-
tradistinction and preference to the single cut-off valve and link arrangements.
In witness whereof, I, the said William Dawes, have hereunto set my hand
and seal, this Sixteenth day of May, in the year of our Lord One thousand
eight hundred and seventy-nine.
Witness,
JOE PHEASEY,
100, Woodhouse. Lane,
Leeds.
WILLIAM DAWES. (L.S.)
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