IMPROVEMENTS IN MOTIVE POWER ENGINES AND GENERATORS IN WHICH THE PRESSURE IS DERIVED FROM THE COMBUSTION OF INFLAMMABLE GAS OR VAPOUR."
Year: 1880

page_text: LETTERS PATENT to Sam Hallam and George Lamb Scott, of Manchester, in
the County of Lancaster, Engineers, for an Invention of "IMPROVEMENTS IN
MOTIVE POWER ENGINES AND GENERATORS IN WHICH THE PRESSURE IS
DERIVED FROM THE COMBUSTION OF INFLAMMABLE GAS OR VAPOUR."
PROVISIONAL SPECIFICATION left by the said Sam Hallam and George
Lamb Scott at the Office of the Commissioners of Patents on the 16th
February 1880.
SAM HALLAM and GEORGE LAMB SCOTT, of Manchester, in the County of Lancaster,.
Engineers. "IMPROVEMENTS IN MOTIVE-POWER ENGINES AND GENERATORS IN
WHICH THE PRESSURE IS DERIVED FROM THE COMBUSTION OF INFLAMMABLE
GAS OR VAPOUR."
Our Invention relates to apparatus employed in the obtainment of motive power
wherein gas is employed in the generation of propelling force. We consume the gas
to generate steam, and we provide incans and arrangements whereby the products
of combustion are employed as propelling media in aid of the steam. Carburretted
hydrogen or other suitable gas and air are separately compressed and are introduced
in proportions suitable to effect combustion into a combustion chamber formed in a
steam generator, in which chamber the gas or mingled gases is or are ignited. The
heat arising from the said combustion is employed to generate steam. The products
of combustion are passed into a chamber, smoke box, or passage, which communicates
through a back-pressure valve with the interior of the steam generator, or with the
steam space or passage. We prefer to arrange that the said products may at times
be discharged into the atmosphere or directly into tho cylinder of the engine to
start the engine. We also prefer to pass the said products into water in a separator
in order to deposit carbonaceous matter and to provide such separator with a blow-
off valve. The said separator may form part of the generator and communicate
with the water and steam spaces. In the form of apparatus which we now consider
to be suitable, the generator consists of an outer cylindrical casing and an inner
cylindrical fire-box or combustion chamber. The lower part of the tire-box which
contains the gas furnace is made of less diameter than the upper part, and the
connection between the two parts forms a bevel ledge or pocket. At suitable
intervals inclined water-tubes connect the water space of the pocket with the space
over the crown of the fire-box. Around the outer edge of the fire-box crown are
arranged flue tubes to convey the products of combustion to the smoke chamber or
Price 67.1

page_text: box on the top or crown of the exterior shell of the generator. To facilitate cleaning
or repairs the joints connecting the crown of the generator and the lower portion of
the firebox with the outer shell may consist of accurately faced angle iron or other
rings secured together by screwed bolts and nuts with copper or other joint rings
inserted between the faces. A cast iron foundation box or bed plate is constructed
with cavities or spaces of suitable capacity to form the reservoirs for compressed air
and gas. Another form of generator may consist of an outer cylindrical or
other shaped shell, enclosing an inner combustion or fire-box surrounded and
covered with water. At a suitable height above the furnace is fixed a dished or
other formed plate, and during the working of the engine means are provided for
throwing on to this plate an adjustable volume of water. The steam thus generated
is passed together with the products of combustion into a separator in the manner
previously indicated.
Arrangements are made for admitting the necessary atmospheric air to support
combustion direct to the furnace when it is desired to get up steam to start the
engine, coal or other combustible gas being admitted direct from a gas main or
reservoir to burners in the furnace chamber or fire-box, and an outlet or branch
leading to the external atmosphere being also opened to allow the products of
combustion to escape into a chimney or directly into the outer air. As soon as n
sufficient pressure of steam is generated the engine is set in motion, the valves
connected to the air reservoir and escape pipe are closed, and the gas and air are
delivered in suitable volumes by their respective pumps to sustain under pressure
the combustion in the furnace chamber. The heat evolved by such combustion is
given out to the water in the generator, and as soon as the pressure in the furnace
chamber becomes higher than that in the boiler the aforesaid back-pressure valve
opens and the products of combustion are discharged into the separator or generator,
whereby their temperature is reduced to that corresponding to the boiling point of
water under the given working pressure. The said products then mingle with the
steam produced by the generator and pass with it to the working cylinder. To
ignite the gas in the combustion chamber we may arrange to pass hydro-carbon gas
through spongy platinum and then raise it to a temperature sufficiently high to
ignite the mingled gas and air previously admitted, whereby we also provide means
for getting up pressure to start without previously raising steain. A piston,
plunger, or flexible diaphragm loaded to suit the working pressure is made to
control by suitable connections the admission of air and gas to the compressing
pumps, according as the pressure in the generator tends to rise or fall.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Sam Hallam and George Lamb Scott in the Great Seal Patent
Office on the 16th August 1880.
SAM HALLAM and GEORGE LAMB SCOTT, of Manchester, in the County
of Lancaster, Engineers. "IMPROVEMENTS IN MOTIVE-POWER ENGINES AND
GENERATORS."
Our Invention relates to apparatus employed in the obtainment of motive power,
wherein gas is employed in the generation of propelling force. We consume the
gas to generate steam, and we provide means and arrangements whereby the
products of combustion are employed as propelling media in aid of the steam.
Carburetted hydrogen or other suitable gas and air are separately compressed, and
are introduced in proportions suitable to effect combustion into a combustion
chamber formed in a steam generator, in which chamber the gas or mingled gases
is or are ignited. The heat arising from the said combustion is employed to
generate steam. The products of combustion are passed into a chamber, smoke
box, or passage, which communicates through a back pressure valve with the
interior of the steam generator, or with the steam space or passage. We prefer to
arrange that the said products may be discharged into the atmosphere, or directly
into the cylinder of the engine to start the engine. We also prefer to pass the
said products into water in a separator, in order to deposit carbonaceous matter,
and to provide such separator with a blow off valve. The said separator may
form part of the generator, and communicate with the water and steam spaces.
In the form of apparatus which we now consider to be suitable, the generator.
consist of an outer cylindrical casing, and an inner cylindrical fire box or
combustion chamber. The lower part of the fire box which contains the gas
furnace is made of less diameter than the upper part, and the connection between
the two parts forms a bevel ledge or pocket. At suitable intervals inclined water
tubes connect the water space of the pocket with the space over the crown of the
fire box. Around the outer edge of the fire box crown are arranged flue tubes to
convey the products of combustion to the smoke chamber or box on the top or
crown of the exterior shell of the generator. To facilitate cleaning or repairs the
joints connecting the crown of the generator, and the lower portion of the firebox
with the outer shell, may consist of accurately faced angle iron or other rings, held
or secured together by screwed bolts and nuts, with copper or other joint rings
inserted between the faces. A cast iron foundation box or bed plate is constructed
with cavities or spaces of suitable capacity to form the reservoirs for compressed
air and gas. Another form of generator may consist of an outer cylindrical or
other shaped shell enclosing an inner combustion chamber or fire box surrounded
and covered with water. At a suitable height above the furnaco is fixed a dished
or other formed plate, and during the working of the engine means are provided
for throwing on to this plate a suitable and adjustable volume of water. The
steam thus generated is passed together with the products of combustion into a
separator in the manner previously indicated. Arrangements are made for
admitting the necessary atmospheric air to support combustion direct to the furnace
when it is desired to get up steam to start the engine, coal or other combustible
gas being admitted direct from a gas main or reservoir to burners in the furnace
chamber or fire box, and a valve or branch leading to external the atmosphere
being also opened to allow the products of combustion to escape into a chimney or
directly into the outer air. As soon as a sufficient pressure of steam is generated
the engine is set in motion, the valve connected to the air reservoir and escape pipe
are closed, and the gas and air are delivered in suitable volumes by their respective
pumps to sustain under pressure the combustion in the furnace chamber. The

page_text: heat evolved by such combustion is given out to the water in the generator, and
so soon as the pressure in the furnace chamber becomes higher than that in the
boiler, the aforesaid back pressure valve opens, and the products of combustion are
discharged into the separator or generator, whereby their temperature is reduced
to that corresponding to the boiling point of water under the given working
pressure. The said products then mingle with the steam produced by the generator
and pass with it to the working cylinder. To ignite the gas in the combustion
chamber when requisite or under pressure we may arrange to pass hydro carbon
gas through spongy platinum, and then raise it to a temperature sufficiently high
to ignite the mingled gas and air previously admitted, whereby we also provide
means for getting up pressure to start without previously raising steam. A piston,
plunger, or flexible diaphragm loaded to suit working pressure is made to control
by suitable means the admission of air and gas to the compressing pumps according
as the pressure in the generator tends to rise or fall.
And in order that our Invention may be fully understood we have attached
hereunto a Sheet of Drawings made to a scale of about one and a half inches to
the foot, and marked with letters of reference. Referring to the said Drawings,
Fig. 1 represents a side elevation, and Fig. 2 a front elevation partly in section
of an engine and generator constructed in accordance with our Invention. In
the said Figs., A is the steam generator; B is the separator; C is the steam
cylinder; D is the air pump, and E is the gas pump, which latter is separately
represented in Fig. 3. The outer cylindrical shell a of the generator is provided
with a flanch a¹, whereby the generator is bolted or secured to a foundation bed
F, the meeting surfaces being by preference planed so that an air tight joint may
bo formed. The lower end of the generator projects into a chamber g which is
formed in the said foundation bed, and into this chamber compressed air is forced
by the means hereinafter indicated. Within the generator is is a fire-box, which is
contracted at its lower end so as to form an annular water pocket, from which
inclined water tubes i extend to the crown of the fire box. From the said crown
a ring of fire tubes i¹ extends to the top plate a³ of the generator, and connects the
interior of fire box with a "smoke-box" ; which is formed on or secured to the top
of the generator. In the lower part of the fire box is a gas burner k, which in the
example consist of a perforated block made of fire-clay or refactory material.
Into the lower ends of these perforations project gas nozzles which are in commu-
nication with a gas-chamber l, into which gas is compressed. When the engine is
at work, gass issues through the said nozzles, and mingling with currents of air
from the chamber g, passes upwards through the perforations in the burner k, and
the mixture burns within the fire-box and furnishes the heat necessary to generate
steam from water which is supplied to the water space. The products of
combustion pass between the tubes i and through the tubes into the smoke
box. To the said smoke box is attached a valve chamber m, in which is seated a
back pressure valve. A pipe n extends from the valve chamber m to the separator
B, into which the said pipe enters and extends downwards below the water level in
the generator, as indicated by dotted lines. The separator consist of a cylindrical
vessel which is in free communication with the steam and water spaces in the
generator by means of branches o, o'. When the pressure of the accumulated gases
is sufficient to lift the said back-pressure valve, the said gases pass in the indicated
direction into the separator, and by' passing through the water therein, parts with
any carbon or sooty matter which they may carry over. We have styled the
vessel B the separator because the carbon is therein separated from the other
products of combustion, but the said vessel also serves as a mixing chamber for the
gases and steam. The gases part with their excess of heat to the water, theroby
aiding in the generation of steam, and mixing with the steam pass through the
outlet pipe and stop valve p, and governor valve p¹, to the valve box of the steam
cylinder. A second safety valve q is mounted on the top of the separator, and the
generator is fitted with ordinary or suitablo gauges and mountings. The piston of
the air pump D is secured to the steam piston rod, and the said rod is connected

page_text: with a crank shaft r. The said air pump in the example is single acting, and is
provided with suitable inlet and outlet valves S. The outlet, valve communicates
with an air pipe t, which conveys the air compressed by the pump into the
chamber g. Upon the crank shaft is fixed an excentric u, and the "strap" of this
excentric is connected with the piston of the gas pump, which latter is provided
'with suitable inlet and outlet valves. The gas compressed by the said pump is
conveyed into the chamber . The said excentric strap is also connected by a link
with the ram of a force pump v. The cylinder of the air pump is "jacketed," and
water is conveyed into the space between the jacket and the said cylinder, in order
to prevent overheating of the said cylinder. The said space communicates through
a valve and pipe w with the inlet valve of the pump v, and the outlet valve of the
said pump communicates with a feed-water heater of any suitable construction
which is heated by the exhaust which is conveyed from the steam cylinder through
a pipe y. The heated water passes through the pipe at the upper end of the
heater into the separator. A second valve chamber is fixed to the top of the
smoke box, and contains a valve which is pressed to its seat by means of a spiral
spring a, which keeps the valve closed during the ordinary working of the engine,
but yields in the event of an excessive pressure in the generator, as for example, in
the event of an explosion of gases. The said valve can be raised by means of a
hand wheel b¹, and when so raised the products of combustion have free agress
through a pipe c' to a chimney or into the outer air. A valve door can be
opened to admit air directly into the chamber g, and suitable arrangements are
made for the direct supply of gas from the main or source of supply to the gas
chamber. To get up steam preparatory to starting the engine, the valve
raised by turning the wheel b', and the valve door d¹ is opened. The gas is now
lighted through the valve opening d', or through a suitable valve opening which
may be provided in the side of the generator, although such opening does not
appear in the Drawings. The products of combustion can now escape freely into
the chimney or outer atmosphere through the pipe c¹. When sufficient steam
is
pressure to start the engine is obtained, the valve and the valve door d' are closed,
and the engine is started. The direct supply of gas is now shut off from the
chamber , and the engine maintains a supply of air and gas to the generator.
After some time the gases from the fire-box pass over into the separator as herein-
before mentioned, and thereafter the engine receives motion from the combined
forces of the steam and gases. The supply of gase from the main to the chamber
may pass through a back pressure valve, so that the said supply ceases automatically
after the engine has been started. We may arrange to pass gas through spongy
platinum, so as to raise it to a temperature sufficiently high to enable it to fire a
mixture of gas and air previously admitted to the fire box, in order to obtain a
starting pressure without previously raising steam, or we may start the engine
without raising steam by turning the engine until there is vapour pressure sufficient
to turn the engine, or we may arrange to have reserves of air and gas under pressure
sufficient to supply the engine until a starting pressure is obtained.
We may
employ a suitable governor controlled by the pressure within the generator to
regulate the supply of gas and air. The form of generator which we have illustrated
and the arrangements of valves, pumps, and passages are such as we consider to be
suitable, but they may be greatly varied without departing from the nature and
intent of our Invention. Fig. 4 is a diagram illustrative of a modification which
may be made in the method of generating steam. The flame from the gas and air
is used to heat a plate b, upon which water is delivered at a rate suitable for the
generation of the required quantity of steam. The products of combustion pass
upwards, and mingling with the steam, are conveyed therewith to the steam
cylinder, as in the case of the other example.
Having now fully set forth and indicated the nature of our said Invention, and
the means whereby the same may be carried into effect, we would have it to be
understood that we claim,-
First. The combination of parts forming the prime mover or modifications thereof,

page_text: substantially as set forth and indicated hereinbefor, and in and by the accom-
panying Drawings.
And, Secondly. A prime mover in which combustible gas and air to support
combustion are supplied, and burnt under pressure to furnish heat to generate
steam, the gaseous products of combustion being caused to mingle with the steam,
the mingled steam and gases acting as a propelling medium for the said prime-
mover.
In witness whereof, we, the said Sam Hallam and George Lamb Scott, have
hereunto set our hands and seals, this Fourteenth day of August, in the
year of our Lord One thousand eigh hundred and eighty.
(L.S.)
SAM HALLAM.
GEORGE LAMB SCOTT. (L.S.)