IMPROVED APPARATUS FOR SUPERHEATING AND REGULATING THE SUPPLY OF STEAM OR OTHER MOTIVE FLUID TO ENGINES
Year: 1884

page_text: I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, London in the County of Middlesex do hereby declare the
nature of said Invention for "IMPROVED APPARATUS FOR SUPERHEATING AND
REGULATING THE SUPPLY OF STEAM OR OTHER MOTIVE FLUID TO ENGINES, 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 apparatus to be used in connection with steam or other
engines for regulating and superheating the supply of steam or other motive
fluid thereto, and comprises the novel construction and arrangement of parts as
hereinafter described.
In the accompanying Drawing
Figure 1 is a sectional elevation of apparatus constructed according to this
Invention, and
Figure 2 is a similar view illustrating a modification.
In applying the said Invention to a steam engine I provide a metallic cylinder, A,
within which is a piston B dividing the said cylinder into two chambers a and b.
A screw C passes vertically through a screw-threaded aperture in the centre of the
piston B and is supported upon a central projection or bearing formed at the
bottom of the cylinder. The head of the said screw is provided, outside the said
cylinder, with a bevel wheel D. At the two extremities of a shaft E are fixed,
back to back, two bevel wheels a¹ a²; the said shaft is supported horizontally
upon two bearings. The wheel a¹ gears continuously with the bevel wheel D of
the screw C, and the wheel a³ is arranged so as to be actuated by one or the other
of two bevel wheels a³ a integral with the sliding sleeve of a governor F. The
said governor F receives a rotary motion from the engine, which motion it
transmits, when necessary, to the screw C by means of one of the bevel wheel a³
or a. The screw C thus rotates either to the right or to the left hand, thereby
causing the piston B to ascend or descend in the cylinder. A rod t fixed to both
extremities of the cylinder A, and passing through the piston, prevents the latter
from turning. By reason of the motion of this piston the capacity of the chamber a
may be either increased or decreased. The power required for actuating the

page_text: governor is obtained from the motor shaft of the engine and is provided with means
for throwing the said governor into, or out of, gear with the said shaft.
A box G is provided into which steam from the boiler Q is admitted through
the tube O. When the cylinder A is, as shewn in Figure 2, fitted upon the main
cylinder, the chamber a serves as a steam holder.
The slide-valve H serves to connect the chamber a either with the boiler Q or
with the cylinder m as shewn in Figure 1. The slide valve is hollow in order to
connect the steam'ports p and pl after the steam from the boiler has entered the
chamber a. In Figure 2 this slide valve is shewn solid, its motion being such as
to alternately open the ports p p. A rod I receives from an excentric
reciprocating motion which it transmits to the slide valve H in such a manner that
this slide valve rapidly opens and closes the ports p p¹ so that the steam from the
boiler shall enter the chamber a and reach the piston K previous to its reaching
the end of its stroke.
A rod J is fixed upon the piston B, and, sliding through a stuffing box and
through the upper cover of the cylinder A. by the side of a graduated bar, indicates
at any time, when the engine is in motion, the exact volume of steam enclosed in
the chamber a and the tube o¹ connected with the engine. Tlie apparatus shewp
in Figures 1 and 2 may be provided with a safety valve, a manometer, a blow off
cock and other suitable fittings, and constitutes an expansion device which can
operate usefully even without being enclosed by a casing full of steam although its
combination with a superheater ensures its greater efficiency.
As shewn in Figure 1. the cylinder A is surroundel by-a steam jacket-e-which-is-
also heated by the gases from the furnace, which gases are raised to a temperature
of from 500 to 600 degrees centigrade. The quantity of heat passing around the
jacket may be regulated by means of a damper 2.
The steam from the boiler enters both the jacket e and the chamber b. The
chamber a whence the steam passes in order to act upon the piston K is thus
heated on all sides.
It is essential in the combination of the superheater with the expanding device
that the capacity of the pipe o¹ shall be ascertained in order to know accurately at
any time during the operation of the engine the volume of steam which it contains,
this volume being the smallest which can be utilized. Thus arranged, the heat-
regulating apparatus permits the engine to be actuated, first by means of saturated
steam the liquid particles of which have been previously vapourized; secondly, by
means of slightly superbeated steam and thus rendered almost insensible to the
cooling action and partial condensation; thirdly, by means of steam superheated
beyond 200 degrees centigrade which temperature is much above.condensing point,
the properties of such steam thus becoming gradually those of a permanent gas.
Although the heat introduced at a constant temperature into superbeated steam
is not entirely converted into power, yet by using this regulating apparatus a
considerable portion of this heat is utilized, thereby effecting a considerable
economy.of fuel.
Heretofore the use of superheated steam presented many defect, as the capacity
'of the apparatus used was not in known proportions to that of the cylinder; the
motion of engines actuated by such steam was always irregular and the steam
when beated beyond 240° centigrade burns the engine packing. By my apparatus
the injurious action of high temperatures is obviated because I use asbestos
packing, or bags filled with air or gas in grooves formed in the piston.
.
Moreover, by means of this regulating apparatus, only the proper quantity of
steam required at each stroke of the piston being allowed to enter the superheating
chamber a, the steam can always enter therein at the following stroke of the
piston as there never remains in the cliamber a more than a very minute quantity
of steam under pressure. The chief advantage of this heat-regulating apparatus
is the complete utilization of the expansion of steam. In engines heretofore
"constructed, the admission of steam at full pressure was interfered with by an

page_text: expansion device and only entered the cylinder after throttling, and wire drawing,
which suddenly lowered its pressure. This is the period of admission at full
pressure. The steam thus admitted being cut off from the boiler was allowed to
expand, but as soon as it had commenced to produce useful work a resistance was
caused by the steam under the piston which was prevente from escaping by
reason of the slide-valve closing the port too soon, and which had to be compressed.
This period is called that of compression. A loss of power thus occurred as only a
small portion of the cylinder was left for the expansion of the steam.
By using this improved heat-regulating apparatus, nearly the whole of the space
in the cylinder is available for the expansion of the steam.
Assuming the engine to be in motion, the governor having regulated the capacity
of the chamber and steain having entered therein, the slide valve plices this
chamber in communication with the cylinder m. The steam enclosed in the
chamber a and in the pipe of instantaneously expands and pushes the piston K
forward. Until the end of its stroke and during the time occupied by the expansion
of the steain, the latter is in contact with the chamber a that to say, with a
source of heat. Moreover compression does not take place at the rear of the
piston K, since the steam escapes freely through the port p which remains open
until the steam from the chamber a enters the port p₁ in order to lessen the shock
of the piston K and force it back in an opposite direction. This heat regulating
apparatus embodies a novel mode of mechanical utilization of stean, and when
applied to a steam engine causes the latter to move regularly, prevents any water
from being carried mechanically into the cylinder, and avoids the periods of full
pressure and compression, there being instead but one single period, that of
expansion, consequently the thermal fall is fully utilized and the maximum amount
of power is obtained from the minimum amount of steam. Lastly, by indicating,
at any time when the engine is in motion, the exact volume of the steam admitted,
this heat-regulating apparatus permits the formation of a table of successive
pressures of steam (saturated or superheated) and the corresponding temperatures
and a diagram the area of which will represent the amount of work done.
Instead of using steam in my apparatus I may, if desired, utilize other
compressed gases such as for instance air compressed by means of water-falls,
wind-mills and the like. In this case, the boiler is repla ed by an air or gas holder
and the air or gas is introduced in suitable quantity into the chamber a, by the
engine and conveyed to the cylinder, being thus used more economically than if it
were introduced into the cylinder directly it came from the air or gas holder.
This air may also be heated in the manner above described with reference to
steam.
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 :-
First. The application of a ball or other governor of a steam or other engine
driven by fluil under compression for regulating the quantity of steam, or
compressed fluid introduced into the cylinder at each stroke of the piston in such a
manner as to dispense with the introduction of the fluid at full pressure, its
expansion being utilized during its introduction, substantially as set forth.
Second. The interposition between the engine motor cylinder and the boiler or
gas holder, of a chamber, the capacity of which is regulated by the governor of the
engine, the fluid required for action in the cylinder being admitted from this.
chamber by means of a s'ide valve placed between the said chamber and the
cylinder, the said valve inte: rupting at this moment the communication between
the chamber and the, boiler or gas holder in such a manner that the expansion of
the steam or other fluid is utilized as soon as it commences to enter the cylinder,
substantially as set forth.
Third. The application of a steam jacket surrounding the chamber which
receives the steam to be introduced into the cylinder at each stroke of the piston,

page_text: in such a manner as to constitute a steam superheater, substantially as above
described.
Fourth. The two arrangements of apparatus above described and shewn in
Figures 1 and 2 of the accompanying Drawing, the said apparatus being provided
with a hollow, or a flat and solid, slide valve, and a steam chamber the capacity of
which is regulated by the governor of the engine, substantially as described.
Dated this 16th day of February 1884.