IMPROVEMENTS IN THE MODE OF APPLYING AND UTILIZING HEATED AIR, AND IN HOT AIR ENGINES OR HYDRO-PHEIWATIG MOTORS
Year: 1875

page_text: LETTERS PATENT to Honry Fisher and John Hunter Rutherford, both
of the Town and County of Newcastle-upon-Tyne, the said Henry
Fisher being an Ironfounder, and the said John Hunter Rutherford
being a Physician and Surgeon, for the Invention of "IMPROVEMENTS
IN THE MODE OF APPLYING AND UTILIZING HEATED AIR, AND IN HOT AIR
ENGINES OR HYDRO-PHEIWATIG MOTORS ”
Sealed the 11th June 1875, and dated the 6th January 1875.
PROVISIONAL SPECIFICATION left by the said Henry Fisher and
John Hunter Rutherford at the Office of the Commissioners of
Patents, with their Petition, on the 6th January 1875.
We, HENRY FISHER and JOHN HUNTER RUTHERFORD, both of the
Town and County of Newcastle-upon-Tyne, the said Henry Fisher being
an Ironfounder, and the said John Hunter Rutherford being a Physician
and Surgeon, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MODE OF APPLYING AND UTILIZING HEATED AIR, AND IN
HOT AIR ENGINES OR HYDRO-PNEUMATIC MOTORS," to be as follows:-
This Invention of improvements in the mode of applying and utilizing
heated air, and in hot air engines or bydro-pneumatic motors, is designed

page_text: to obviate the main objections which have hitherto existed in hot air
engines and motors, viz., the difficulty of lubricating the working parts
and the excessive heating to which they have been subjected. It relates
to the application and use of a column of water to transmit the power
obtained by the expansion of heated and compressed air to the work t
to be done and the utilization of the heat in the rejected air. For
this purpose air highly compressed is heated in a furnace and then passed
into a chamber, where it comes in contact with a column of water. The
pressure and expansion of the air operate upon the column, giving
motion to it, which motion can be communicated to a reciprocating 1
piston or other mechanical arrangement for converting or applying
power.
Our improved engine is composed of three essential parts, viz., an air
compressor, an air heating furnace or apparatus, and a working chamber
or chambers.
The operation of the engine is as follows:-The air is compressed in
the compressor to any required pressure and forced into the furnace or
heating apparatus, where it is intensely heated. It is then allowed to
pass into the working chamber, where it expands, displacing a column of
water thercin contained, which transmits the power developed by the ?
expansion of the heated and compressed air by means of a piston or
other mechanical arrangement to the work to be done.
The heat in the rejected air may further bo utilized in a steam boiler in
the ordinary manner where steam is generated, and may be applied to an
auxiliary engine principally used to compress the air and force it into a
the furnace.
The supply of water in the chamber being constantly renewed keeps
all tho working parts cool and renders unnecessary any more than
ordinary lubrication of any machine.
This Invention is applicable to screw propulsion, water jet propulsion,
raising water, cranes, hoists, driying machinery, and practically to every
purpose to which the steam engine is applied.
]

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Fisher and John Hunter Rutherford in tho
Great Seal Patent Office on the 6th July 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, HENRY
FISHER and JOHN HUNTER RUTHERFORD, both of the Town and County
of Newcastle-upon-Tyne, the said Henry Fisher being an Ironfounder,
and the said John Hunter Rutherford being a Physician and Surgeon,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of January, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Henry Fisher and John Hunter Rutherford,
Her special licence that we, the said Henry Fisher and John Hunter
Rutherford, our executors, administrators, and assigns, or such others
as we, the said Henry Fisher and John Hunter Rutherford, our exc-
cutors, 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 THE MODE OF APPLYING AND UTILIZING HEATED AIR, AND IN HOT AIR ENGINES
OR HYDRO-PNEUMATIC MOTORS," upon the condition (amongst others) that
we, the said Henry Fisher and John Hunter Rutherford, our executors
or administrators, by an instrument in writing under our, 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 bo 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 we, the said Henry Fisher and John Hunter
Rutherford, do hereby declare the nature of our said Invention, and
in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement thereof (that is to
say):-
This Invention of improvements in the mode of amolvine and utilizing

page_text: Fig. 1, Sheet 1, shews in elevation an engine embodying our Invention;
Fig. 2 is a plan.
Fig. 3, Sheet 2, is a longitudinal section of the general arrangement.
Fig. 4 is a vertical section of the furnace A.
Fig. 5 is an enlarged elevation of the exhaust and surplus valves.
Fig. 6 is an elevation of the feed valve.
Fig. 7 is a section of the valve through the line a¹, b'.
Fig. 8 is a section through the lines c', d³, of the central or moving
part of the valve, which is open at both ends so that the water may pass
freely through and so keep it cool.
Fig. 9 is a plan of one of the valve chests of the air compressor B,
which is of the ordinary kind, and is worked direct from the piston of
the engine.
A is the furnace, through which compressed air is forced by means of
the compressor B. The resulting gas is then passed on by means of the
pipe a and the feed valves D, D, to the working chambers 0, 0, which
are attached one to each end of the cylinder and piston E, and are
kept full of water up to the line 8, 8, as shewn in the section Fig. 3,
Sheet 2. The intensely heated gas is then admitted alternately into the
chambers O, O, and is there allowed to expand, and its power is thereby
transmitted directly by means of the water to the piston.
F, F, are exhaust and surplus discharge valves, they being designed
both for the purpose of acting as exhaust valves for the hot gas and
discharge valves for the surplus water, as there is a small quantity of
water injected into each chamber at every stroke by means of the circu-
lating pump G and the pipe 6 for the purpose of keeping the water in
the working chambers cool. It will therefore be seen that there will be
a certain quantity of water to be discharged by means of the valves Fat
every stroke. The heated gas after having passed through the exhaust
valves may be discharged into an ordinary steam boiler for the purpose
of generating steam, the resulting steam being utilized for working the
air compressing pump or any other purpose, or it may be discharged into
any other form of economiser or regenerator suitable for extracting the
heat from the rejected air, For the sake of simplicity any special method

page_text: of utilizing the waste heat is not shown in the Drawing. H is a tank
containing the valves D, D, and F, F, and the chambers C, C, and is
kept full of water up to the line t, as shewn in section, Fig. 3, Sheet 2,
so that the whole of the parts exposed to the intensely, heated gas are
immorsed, and will not therefore be heated to more than about 300°,
hence this plan will enable intense heat to be applied without any fear
of damage to the working parts of the apparatus. Tho tank H may
also be used with a covered top and stayed sufficiently strong to withstand
any pressure of steam that may be generated in the passage of the hot
gas through the valves and chambers. The steam thus obtained may be :
made to act in conjunction with the steam boiler already mentioned, or
it may be condensed and the effect of the vacuum made useful. There
are no stuffing boxes exposed to the hot gas, no joints, and the least
possible quantity of finished surface, and it will be seen that nearly tho
whole of the heat contained in the fuel may be utilized by this
system. The valves D, D, and F, F, are worked by an arrangement
of cams and levers I, I, from the main shaft J of the engine by means
of countershafts as shewn.
Referring to Fig. 4, the compressed air is injected through the pipo e,
passing through the firo and out at the pipe a, which with the furnace is a
lined with fire-brick. The space is for receiving the ash, which is
removed by means of the door i. K is a valve case for the purpose of
charging the furnace when under pressure. The cover d is made to fit
air tight upon the top of the hopper e. The slide valve is composed
of an open and a blank end, as shown in the section. When it is moved
along by means of the handle and screw g so as to bring the blank end
over the top of the furnace the communication is shut off from the
hopper c. The cover d is then removed and the charge of fuel put into
the hopper, the cover replaced, and securely fastened by means of the
bolts, as shewn. The slide valve is then moved along until the open end a
is over the top of the furnace, and the charge then falls through. The
valve is then moved back and the operation repeated when required.
The valve case K is kept full of water, which is made to circulato by
means of the pump G and the small pipe k and 1, and thus tho valvo is
kept cool, the circulating water not being under pressure.
Having described the nature of our said Invention, and explained one
manner of carrying it into practical effect, we hereby declare what wo
consider to be novel and original, and therefore claim as the Invention

page_text: secured to us by the herein-before in part recited Letters Patent
to be,-
First. The employment of a body of water as a transmitting medium
between the power generated in the furnace by the heating and expansion
of the compressed air and the work to be done.
Secondly. The mode of utilizing the heat in the air that has done duty
in the chambers CO by connecting said chambers with a boiler by means
of a pipe, the discharge of air into which is regulated by the valves Fas
above described.
And, Thirdly. The construction of hydro-pneumatic motors in which
apparatus for compressing and heating air are combined with working
chambers charged with water, the whole being arranged and operating
substantially as shown in and described with reference to accompanying
Drawings.
In witness whereof, we, the said Henry Fisher and John Hunter
Rutherford, have hereunto set our hands and seals, this Third
day of July, in the year of our Lord One thousand eight hundred
and seventy-five.