IMPROVEMENTS IN HOT AIR ENGINES
Year: 1879

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
IMPROVEMENTS IN HOT AIR ENGINES." A communication from abroad by
Henry W. Sherrill, of Jersey City, New Jersey, United States of America.
65
:
aled the 12th September 1879, and dated the 20th March 187
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 20th March 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN HOT AIR ENGINES." [A
communication from abroad by Henry W. Sherrill, of Jersey City, New Jersey,
United States of America.]
This Invention relates to improvements in hot air engines, and comprises means
for utilizing the pump piston and the engine piston, means for heating the air before
its entrance into the furnace by means of the exhaust air from the engine, means
for shaking and feeding the furnace fire without opening the furnace, and means for
combining a safety valve and governor.
One part of the said Invention consists in the combination of an engine cylinder
and piston, a pump cylinder and piston separate therefrom, and a passage or pipe
conveying heated air from the furnace to the pump-piston, whereby the latter is
made to aid the engine piston in its work. The pump piston may be arranged
directly over the furnace, and the engine cylinder at one side of it, or the engine
cylinder may be arranged on the furnace, and the pump cylinder above the engine
cylinder.
Another part of the said Invention consists in the combination of an engine
cylinder and piston with a pump cylinder and piston arranged side by side, and a
walking beam, whereby a very compact and powerful hot air engine is obtained.
Another part of the said Invention consists in the combination of an engine
cylinder and piston, a pump cylinder and piston, a single valve for controlling the
admission of hot air to them, and another single valve for controlling the exhaust
I Price di

page_text: of air from them, whereby the simplicity and compactness of the engine are
enhanced.
Another part of the said Invention consists in the combination in a hot air engine
with an induction pipe or passage for conducting air to the furnace of an exhaust
pipe or passage, for conducting the hot air exhausted from the engine in proximity
to said induction pipe, whereby air is partially heated before entering the furnace of
the engine.
Another part of the Invention consists in the combination with the furnace in a
hot air engine of a feeder of novel construction, whereby it may be automatically
fed with fuel, and the opening of the furnace for the purpose of feeding the fire, and
the consequent checking of the engine incident to the cooling of the furnace are
avoided.
Another part of the said Invention consists in the combination with the furnace
in a hot air engine of a shaking grate, whereby the fire may be shaken without
opening the furnace.
Another part of the Invention consists in the combination with the furnace in a
hot air engine of a feeder for automatically supplying the fuel, and a shaking grate,
whereby the fire may be supplied with fuel and shaken without opening the
furnace.
Another improvement consists in the combination with a hot-air engine of a
safety valve therefor, and a governor applied to said safety valve, whereby the
construction and operation of the engine are materially simplified, one valve
serving the functions of the separate safety valve and governor valve usually
employed.

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
20th September 1879.
A
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. " IMPROVEMENTS IN HOT-AIR ENGINES."
communication from abroad by Henry W. Sherrill, of Jersey City, New Jersey,
United States of America.
One part of this Invention consists in the combination of an engine cylinder and
piston, a pump cylinder and piston separate therefrom, and a pipe or passage con-
veying heated air from the furnace to the pump-piston, whereby the latter is made
to aid the engine piston in its work.
The said pump-piston may be arranged directly over the furnace, and the engine
cylinder at one side of it, or the engine-cylinder may be arranged on the furnace,
and the pump-cylinder above the engine-cylinder.
Another part of the said Invention consists in the combination of an engine-
cylinder and piston with a pump-cylinder and piston arranged side by side, and a
walking beam connecting said pistons, whereby a very compact and powerful hot-
air engine is obtained.
Another part of the said Invention consists in the combination of an engine
cylinder and piston, a pump cylinder and piston, a valve for controlling the admis-
sion of hot air to both of them, and another valve for controlling the exhaust of
air from them, whereby the simplicity and compactness of the engine are
enbanced.
Another part of the said Invention consists in the combination with the furnace
in a hot air engine of a feeder of novel construction, whereby it may be fed with
fuel, so that the opening of the furnace for the purpose of feeding the fire and the
consequent checking of the engine incident to the cooling of the furnace are
avoided.
Another part of the said Invention consists in the combination with the furnace
in a hot-air engine of a shaking grate, whereby the fire may be shaken without
opening the furnace.
Another part of the said Invention consists in the combination with the furnace
in a hot air engine of a feeder for supplying the fuel, and a shaking grate, whereby
the fire may be supplied with fuel and shaken without opening the furnace.
Another part of the said Invention consists in the combination with a hot air
engine of a safety valve therefor, and a governor applied to the said safety valve,
whereby the construction and operation of the engine are materially simplified,
one valve serving the functions of the separate safety valve and governor valve
usually employed.
Other parts of the Invention consist in details hereinafter described.
In the accompanying Drawing,
Figure 1 represents a central vertical section through both cylinders of the said
engine.
Figure 2 is a plan thereof.
Figure 3 is an elevation opposite the end of the walking beam.
Figure 4 is a vertical section of a portion of the pump cylinder and furnace and
a fuel feeder.
Figure 5 is a vertical section of the pump cylinder and furnace, and the passages,
valves, and their appurtenances, whereby air is admitted to and exhausted from the
Aylindera

page_text: the cooling and consequent checking of the fire, it being provided with a shank or
handle protruding from the furnace for that purpose. A. door C, pivoted at the top
to the shell of the furnace, affords communication with the ash-pit. D, D', D2, (see
particularly Figure 4), designate the shell of a feeder communicating with the
furnace, and whereby fuel may be introduced into it without opening it to the
external atmosphere and thereby occasioning the cooling and checking of the fire.
The compartment D of the said shell consists of a horizontal tube provided with a
screw S, driven by means of a belt on a pulley c, to carry fuel into the furnace.
The compartment D¹ is spherical, and provided with a valve D³ attached to a rod d,
and capable of being lowered to open communication between said compartment
and the compartment D. The compartment D2 is hemispherical, and provided with
a valve D attached to a tubular rod f surrounding the rod d, and permitting the
lowering of the said valve, so as to establish communication between the compartments
D2 and D'. The rods d and f are respectively connected to hand levers D³ and Do,
whereby they may be shifted at pleasure. On the flat top of the compartment D³
is a hopper D. The fuel is introduced into this hopper, and on the opening of the
valve D it passes into the compartiment D¹, and on the closing of the said valve D',
so as to shut off communication with the external atmosphere and opening of the
valve D³, it passes into the compartiment D, whence it is impelled by the screw S
into the furnace A without admitting into the latter air, whereby the fire would be
cooled and the engine checked. E designates a pump cylinder mounted on the top
of the furnace A, and communicating with it by passages E¹ and E2 (see particu-
larly Figure 5), the former of which extends from the lower part of the said cylinder
and the other passage to the upper part of the said furnace. A valve E³ is employed
to control communication between these two passages, and is held up to its seat by a
spring y, and depressed so as to open communication between said passages by a
tappet h on an oscillating shaft E, driven by a rod R, actuated by a crank on a
bevel gear wheel U (see Figures 2 and 5). Another valve E controls the exhaust
of air from the pump-cylinder E, and is held down on its seat by a spring i, and
raised by a tappet ; on the shaft E, and permits the exhaust of air from the said
cylinder. E designates the pump-piston, which it will be understood is impelled
upward by air acting beneath it, and serves to draw air from outside the cylinder
on its descent, and to drive the air through a passage F (see particularly Figure 4)
to the furnace on its ascent. This air passage F is shewn as leading from the top
of the pump cylinder under control of an outwardly opening valve G to the furnace
A under the grate B, and through a small passage k in the compartment D to the
portion of the furnace A above the grate B.
Air enters the top of the pump cylinder through an opening controlled by a
vertically moving valve W in a radial extension or passage X (see Figure 2), the
said valve rising to open and falling to close the said opening.
H designates the engine-cylinder arranged at the side of the pump-cylinder E,
and represented as considerably smaller in diameter than the said pump-cylinder,
the latter having to supply the furnace with air enough to act upon the engine-
piston as well as the pump-piston. This engine-cylinder is open at the bottom, and
supplied with and exhausted of air through a passage I leading to its upper portion
from the lower portion of the pump cylinder, so as to act on the upper side of the
engine piston H. Both the pump-piston-rod and the engine-piston-rod are shewn
provided with cross heads J working in guides K, and connected to the ends of a
walking beam L mounted on suitable standards M, sliding boxes being used at the
points of connection to compensate for the radial action of said walking beam. It
is obvious that the same valves E3 and E control the admission of air to and the
exhaust of air from both cylinders.
Both the pistons E and H' are packed and lubricated on the sides distant from
those on which the air acts in impelling them. In lieu of the cross heads and
guides, trunks and suitable connections may obviously be employed with good
results.
N designates a driving shaft arranged under the engine cylinder H, and connected

page_text: by means of cranks N' and rods at the sides of the said cylinder with one end of
the walking beam L.
The arrangement of the pistons and the driving shaft which I have above described
is advantageous, because it admits of the ready removal of the pistons, one through
the top and the other through the bottom of its cylinder on the detachment of
certain parts to admit of conveniently reaching them.
P designates a passage leading from the furnace A under the grate B, and pro-
vided with an escape passage PI (see particularly Figure 3). In this escape passage
P¹ is a valve P2, the stem of which is connected to a lever P³, whereby it may be
raised or depressed to open or close the outlet opening in the said passage.
One end or arm of said lever P³ is furnished with a weight m capable of adjust-
ment to different positions to control the opening of the valve at different pressures,
and enable it to act as a safety valve. The other end of the lever P³ has connected
to it a rod Q, whose upper end enters the lower end of a rotary shaft T driven by
bevel gear wheels U, Ui, from the driving shaft N. V, V, designate governor balls
attached to arms pivoted to the shaft T, so that their inner ends will impinge upon
the upper end of the rod Q. Whenever the speed of the engine is such as to
sufficiently distend these governor balls, the arms of the latter acting on the said
rod Q force down the end of the lever P³ with which the said rod is connected, and
open the valve P2, thereby permitting the escape of a portion of air in the furnace
A, reducing the pressure therein and checking the engine.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it under-
stood that I claim,―
First. The combination of an engine-cylinder and piston, a pump cylinder and
piston separate therefrom, and a passage or pipe conveying heated air from the
furnace to the pump-piston, substantially as and for the purpose set forth.
Second. The combination of an engine cylinder and piston with a pump cylinder
and piston arranged side by side, and a walking beam connected to the said pistons,
substantially as and for the purpose set forth.
Third. The combination of a furnace, a pump cylinder and piston arranged over
the said furnace, an engine cylinder and piston arranged at the side of the said
pump cylinder, and piston valves for controlling the admission of air to and the
escape of air from the pump cylinder, and a passage or pipe leading from the lower
portion of the pump cylinder to the upper portion of the engine cylinder, and a
walking beam connecting the said piston, substantially as and for the purposes set
forth.
Fourth. The combination of an engine cylinder and piston, a pump cylinder and
piston, a valve for controlling the admission of hot air to both of them, and another
valve for controlling the exhaust of air from them, substantially as and for the
purpose set forth."
Fifth. The combination with the furnace in a hot air engine of a feeder, whereby
it may be fed with fuel, and the opening of the furnace for the purpose of feeding
the fire, and the consequent checking of the engine incident to the cooling of the
furnace are avoided, substantially as set forth.
Sixth. The combination with the furnace of a feeder comprising three compart-
ments, one furnished with a screw, and the others with valves, which may be opened
and closed successively to provide for feeding the furnace with fuel without opening
the said furnace to the external atmosphere, substantially as set forth.
Seventh. The combination with the furnace in a hot air engine of a shaking
grate, whereby the fire may be shaken without opening the furnace, substantially as
set forth.
Eighth. The combination with the furnace in a hot air engine of a feeder for
supplying the fuel, and a shaking grate, whereby the fire may be supplied with fuel
and shaken without opening the furnace, substantially as set forth.
Ninth. The combination with a hot air engine of a safety valve therefor, and a

page_text: governor applied to the said safety valve, substantially as and for the purposes set
forth.
Tenth. The combination of a furnace, an escape passage, a valve controlling such
escape passage, a lever connected with said valve and furnished with an adjustable
weight, and governor balls connected with the said lever, whereby the valve may open
automatically by the pressure of air upon it, or may be opened by the governor
balls when the engine acquires a certain speed, substantially as set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twentieth day of September, in the year of our Lord One
thousand eight hundred and seventy nine.