IMPROVEMENTS IN APPARATUS FOR GENERATING MOTIVE POWER
Year: 1881

page_text: LETTERS PATENT to Richard Hallewell, of Blackburn, in the County of
Lancaster, Engineer, for an Invention of "IMPROVEMENTS IN APPARATUS
FOR GENERATING MOTIVE POWER."
PROVISIONAL SPECIFICATION left by the said Richard Hallewell at the
Office of the Commissioners of Patents on the 23rd November 1881.
RICHARD HALLEWELL, of Blackburn, in the County of Lancaster, Engineer.
"IMPROVEMENTS IN APPARATUS FOR GENERATING MOTIVE POWER."
My Invention relates to the apparatus in which power is derived from the
vapourisation of liquid, and has for its principal object to produce a motor which
could be worked with greater safety than the ordinary steam engines and boilers,
and which would be suitable to be worked at intervals and could be quickly got
ready for action. I have found that when a small quantity of water or volatile
liquid is passed into a heated receiver of sinall capacity as compared with its
heating surface, a high pressure is obtained almost instantaneously, and that the
pressure is not maintained, but falls considerably. I make use of the high pressure
so obtained to act upon the piston or pistons of an engine. The forins of the
generator may be varied. In one form an inner and an outer conical shell are
combined together, so that a small space is left between the two. The outer surface
of the generator, that is to say, the inner surface of the one cone and the outer
surface of the other are preferably provided with radial gills, or with studs or
projections to act as heat conductors. The parts may be cast in copper, or other
suitable metal or alloy, and be turned and bored, so so as to obtain accuracy in the
space, the parts being so bolted or secured together as that they can be readily
separated to obtain access to the interior surfaces. The generator is enclosed within
a casing, which by preference is made double, to enclose a nou-couducting substance,
or the said generator is suitably enclosed and is heated by means of a burning
mixture of carburetted hydrogen gas and air, or of an oil lamp, or a coke fire, or
by other suitable means. I prefer that the capacity of the generator shall not be
more or shall not be much more than suflicient to generate steam for one stroke of

page_text: the engine. When the generator is suitably proportioned I obtain a high initial
pressure, and can use the steam expansively without requiring cut off valves and
motions. The liquid, say for example water, is delivered by means of an injecting
pump, or of a feeding valvo or apparatus, the water being delivered in separate
quantities, each suitable for a single stroke of the engine. The water is conveyed
into a channel which communicates with a circle of holes around the upper end of
the generator, or is conveyed through a valve which delivers the water in a thin
spreading sheet, or the water is otherwise caused to come into contact with the
heated interior surface of the generator as quickly as possible. The engine, or each
cylinder thereof, is or may be single acting. The water may be injected for every
stroke of the engine, or for every other stroke, or at longer intervals, or the times
of injection may be variable and be controlled by the governor. In one arrange-
ment 1 employ a cam to act upon the injector at times as regulated by the governor,
and at the same times the steam valve or valves is or are acted upon to admit
steam to the cylinder. The supply of gas may also be regulated by the action of
the governor. In the cases wherein water is not admitted to the generator for
every stroke of the piston I prefer that the exhaust passage shall remain open
during the stroke made without the admission of steam, so that the exhaust steam
can re-enter the cylinder during the outward strokes. In such a case I discharge
the exhaust stenni in the first instance into a chamber, which is preferably of larger
capacity than the cylinder. To prevent or check the filling up of the space within
the generator by the accumulation of deposit I prefer to condense the exhaust
steam and to admit no water into the generator which has not been distilled or
vapourised and condensed. In lieu of water I may use alcohol or other liquid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Richard Hallewell in the Great Seal Patent Office on the 23rd May
1882.
RICHARD HALLEWELL, of Blackburn, in the County of Lancaster, Engineer.
"IMPROVEMENTS IN APPARATUS FOR GENERATING MOTIVE POWER."
My Invention relates to apparatus in which power is derived from the vapouri-
sation of liquid, and has for its principal object to produce a motor which could bo
worked with greater safety than the ordinary steam engines and boilers, and
which would be suitable to be worked at intervals and could be quickly got ready
for action. I have found that when a small quantity of water or volatile liquid is
passed into a heated receiver of small capacity as compared with its heating surface
a high pressure is obtained almost instantaneously, and that the pressure is not
maintained but falls considerably. I make use of the high pressure so obtained to
act upon the piston or pistons of an engine. The forms of the generator may be
varied. In one form an inner and an outer shell are combined together, so that a
small space is left between the two. The outer surface of the generator, that is to
say, the inner surface of one shell and the outer surface of the other are preferably
provided with radial gills or with studs or projections to act as heat conductors.
The generator is enclosed within a casing, which by preference is made double to
enclose a non-conducting substance, or the said generator is suitably enclosed and
is heated by means of a burning mixture of carburetted hydrogen gas and air, or
of an oil lamp, or of a coke fire, or by other suitable means. I prefer that the
capacity of the generator shall not be more or shall not be much more than
sufficient to generate steam for one stroke of the engine. The engine or cach
cylinder thereof is or may be single acting. The water may be injected for every
stroke of the engine, or for every other stroke, or at longer intervals, or the times
of injection may be variable and be controlled by the governor. To prevent or
check the filling up of the space within the generator by the accumulation of
deposit I prefer to condense the exhaust steam and to admit no water into tho
generator which has not been distilled or vapourised and condensed. In lieu of
water I may use alcohol or other liquid.
"
In order that my Invention may be fully understood I have attached hereunto
a Sheet of Drawings, made about half the full size of the example selected for
illustration, to which Drawings I will refer hereinafter when more fully describing
my Invention. In the said Drawings, Fig. 1 represents my improved prime
mover parts, which may be of ordinary construction, and which aro not necessary
to the proper understanding of my Invention being omitted. In the said Fig., A,
which is represented in vertical section, is the steam or pressure generator, and B
is the cylinder into which the pressure is admitted to act upon the piston b of tho
engine; Fig. 2 represents a horizontal section of the generator taken on the
line In Figs. 1 and 2, a is a metal shell, which in the example is cylindrical in
form but which may be of conical or other suitable formation. The said shell is
cast in one piece, with a number of radial gills or ribs a' which meet in the
centre. The said shell is enclosed within an outer shell c, which is connected
by radial gills or ribs c' with another shell c², the two shells and the said
gills when mado of cast metal being preferably cast together in one piece. The
said parts may be cast in copper, or in an alloy containing a large amount of
copper, or in other suitable metal or alloy, or be made otherwise than by
casting, and be turned and bored so as to leave a small annular space & into
which the fluid, say, for example, water, is injected through a pipe e to be
converted into steam. This said space is intentionally made of very small area,

page_text: so that it will hold only a comparatively small portion of steam, hence the
importance of turning and boring the parts in order to obtain accuracy, but I
do not confine myself to the turning and boring. By way of example I will
state that the said space in a small generator may be about one thirty-second of an
inch wide, and the cubical contents be only about one fourth, or ono sixth, or less
of the contents of the cylinder B; and I consider that in all cases the contents of
the said space should be less than the cylinder contents. The space d is closed at
the ends of the shells by means of a cover f and a flange on the lower end of the
shell a
The cover is secured by means of a nut f¹, which engages with a scrow
thread which is cut upon an extension of the central pillar a formed by the union
of the inner ends of the gills, and the said cover is formed with openings f² for the
passage of heated gases from the fire. The method of securing the said cover may
be varied. In the example the generator, being of comparatively small power, is
heated by means of a fire obtained from a mixture of gas and air.
A gas burner h
is applied at the bottom of the generator, and in the example is hinged at h², so
that it can be lowered when the flame has to be lighted, or when cleaning or
inspection is necessary. When raised, the burner is sustained by means of a hinged
catch. Any suitable form of gas burner may be used, or the heat may be obtained
by the combustion of any suitable fuel. The heated gases from the fire pass
upwards through the spaces between the gills a¹, and impart heat to the said gills
and to the shell a, and passing through the openings in the cover f flow downwards
in the direction indicated by the arrows through the spaces between the gills cand
the shells c and c³, imparting heat thereto. The gases passing below the lower end
of the shell c flow upwards through a space between the said shell and an outer
casing to the chimney j¹. It will be seen that the shells and gills are calculated
to absorb a large portion of the heat generated. I consider the said gills to be very
useful as heat absorbents and to transmit the absorbed heat to the shells a and c.
The water is supplied by means of an injecting pump h, which is worked by means
of a cam l, which is mounted to slide upon a vertical shaft m, which is connected
by means of bevel gearing with the engine crank shaft. The said shaft carries a
governor m' of any suitable construction, which is connected with the cam l, so
that the latter is caused to slide upon the shaft as the speed of the engine varies.
In the example a rod within the shaft, which is hollow, connects the governor with
the said cam. The cam acts upon the pump ram n to inject water, a spring or
suitable appliance giving the outward stroke to the ram, and keeping the anti-
friction bowl n', which is carried by the said ram or by a sliding bar connected
therewith in contact with the cam. The said cain is formed to cause a smaller
quantity of water to be injected, or to stop the supply of water when the engine
exceeds its normal speed, and to increase the supply of water when the engine
speed becomes reduced. The said cam is provided with a conical extension which
ncts upon a lever o which is fixed to a rod or shaft o¹, which is connected with a
valve or tap o upon the pipe which supplies gas to the burner, whereby the
supply of gas is lessened or increased at the same time as the supply of water
is lessened or increased. The cam is so formed as to give a quick action to the
pump ram, so that the supply of water is injected suddenly or very quickly, and
during a small portion of a revolution of the crank shaft. The water is conveyed
from the pump by means of a pipe e, which is broken off in.the Drawing, but is
seen again on the side of the generator. The said pipe opens into a channel
which extends around the upper end of the space d, and is formed by grooving the
opposed surfaces of the shells a and c. The water flows from this channel
downwards into the said space and becomes converted into steam by reason of the
heated state of the two shells. The intention is that the water shall be suddenly
and entirely converted into steam, and shall immediately act upon the piston b.
The cam is so adjusted as that the water shall be injected at about the
commencement or a little before the commencement of the outward stroke of the
piston, and in order that the generated pressure may have immediate access to the
piston, I prefer that in the case of a single-cylinder engine the pressure shall have

page_text: "
The said
free access without having to pass through a valve or through valves. In the
example the steam pressure has free access to the cylinder B through a passage p.
With this passage is connected a passage q for the discharge of the exhaust steam
which is permitted to escape at the required times by lifting a valve r.
valve is actuated by means of a second cam 8 which is fixed upon the shaft m, and
which operates upon a vibrating lover at t, which lever is connected by means of
a rod with a bell-crank lever which acts upon the spindle of the valve. I prefer
that the cam shall be formed to raise the said valve when the piston has just.
commenced its inward stroke, and to permit the valve to close a little before the
termination of the same stroke so as to return a little of the steam into the
generator. In the example the cylinder is jacketted and surrounded with non-
conducting material, and a packing of nsbestos or suitable non-conducting material
is interposed between the cylinder end and the generator to check the transmission
of bent. The action of the machine may be described as follows:-Each time that
the pump injects water into the generator, the water is suddenly expanded and
converted into steam, and I have found that a very high initial pressure is thereby
obtained, but that this pressure becomes greatly and very quickly reduced. The
pressure is therefore at once admitted to act upon the piston which receives an
impulse due to the high initial pressure. As the spaco d is so comparatively small,
nearly all the high pressure steam generated is compelled to pass into the cylinder
and to act upon the piston, and this I consider to be the most important feature in
my Invention, as I do not think it possible to store the high initial pressure
obtained. When the piston has made an out stroke and has commenced to return,
the valve is opened to permit the escape of the exhaust steam, and at about the
beginning of the next out stroke water is again injected into the generator, and
these movements being repeated the engine is kept in motion. In case the engine
has little or no work to do the governor lifts the cam until the supply of water
is suitably reduced, and when necessary the supply ceases for intervals so that one
or more strokes is or are made without water being injected into the generator.
In such cases the exhaust valve is free to open to admit of the return of exhaust
steam when necessary during the out stroke, but I may arrange for the said valve
to be kept open during the strokes made without the injection of water, or the
said cam may be formed to inject water for each and every stroke, but be capable
of reducing the quantity to the amount required simply to prevent the formation
of a vacuum in the generator, especially in cases wherein condensers are employed.
I do not desire any unconverted water to remain in the generator, and it will be
seen that in case there be water remaining in when the exhaust valve is opened, it
will pass away with the exhaust steam. If for any reason the passage p
be situated at a higher point, I make a special passage at the bottom of
the generator and provide it with a "snifting valve" which is opened during
the exhaust period of each stroke. As the space for the generation of
steam is very small it is of great importance that the water shall be very pure in
order that the space may not become filled up with deposit. In case a supply of
sufficiently pure water could not otherwise be obtained I should use distilled
water. This can most conveniently be obtained by condensing the exhaust steam
with a suitable condenser which will return pure or so called distilled water for
the use of the engine. I do not confine myself to the use of water, and may use
alcohol or other suitable liquid, and condense the vapour for the sake of economy
in the quantity of liquid required. When the said space requires cleaning out, the
parts of the generator can be separated by unscrewing the nut f' and lifting off
the outer shell c. I do not confine myself to the particular form of generator
illustrated by the Drawings, so long as the important features are retained, namely,
the comparatively small space for the generation of steam combined with suitably
extensive heating and heat absorbing surfaces, as for example, I may use a tubular
form of generator. It will be seen that by the separate generation of the pressure
for each stroke I am enabled to work expansively without requiring cut-off valves
and motions. I do not confine myself to the employment of a single-acting
"

page_text: cylinder nor of a single cylinder, nor do I confine myself to any of the details of
the engine nor to the principle of action of the engine apart from the generator,
as I shall vary the said details to suit the varying dimensions and intended uses of
the engine, and as I find it to be desirable for any reason. In cases wherein are
employed more than one steam cylinder having pistons not making their out
strokes in unison I should employ a valve or valves which would place each
cylinder in free communication with the generator at the proper times; or I should
employ a separate generator for each cylinder. Although in the example illus-
trated I have not interposed a valve between the generator and the cylinder, I
may so apply a valve, but in such a case I should provide for such valve to be well
open prior to each injection into the generator.
Having now fully described and indicated the nature of my Invention, and the
manner in which I carry the same into practical effect, I would have it to be
understood that I claim,-
First. The motive power apparatus constructed and acting substantially as set
forth and indicated hereinbefore, and in and by the accompanying Drawings.
Secondly. The steam or pressure generator constructed substantially as and for
the purpose set forth and indicated.
Thirdly. A pressure generator having a generating space of such proportions
and so suitably heated as that the pressure required for any single stroke can be
generated by the sudden injection into the generator at a suitable period in the out
or in stroke of the piston of a suitable quantity of liquid, substantially as set forth
and indicated.
Fourthly. A steam generator having free access for the flow of steam to the
engine cylinder or cylinders or equivalent part or parts without the interposition
of a valve, and having liquid injected thereinto at intervals, substantially as set
forth and indicated.
Fifthly. Obtaining pressure of vapour for use in a prime mover by rapidly
injecting liquid into a generator of comparatively small contents, each impulse
being obtained by a separate injection, and the initial pressure resulting from each
injection being at once admitted to act upon the piston or part or parts of the
prime mover, so that advantage is taken of the high initial pressure resulting
from the sudden conversion of liquid into vapour, substantially as set forth and
indicated.
And, Lastly. The motive power engine having a heated pressure generator of
less cubical contents than the cylinder or equivalent part or parts of the engine,
into which generator liquid is injected at intervals, the injector being regulated by
a governor, so that for every stroke of the engine a pressure is obtained in the
generator suitable to the work to be done by the engine, which latter can be
worked expansively without the use of valves or cut-off motions, substantially as
set forth and indicated.
In witness whereof, I, the said Richard Hallewell, have hereunto set my
hand and seal, this Twenty-second day of May, in the year of our Lord
One thousand eight hundred and eighty two.
Signed, sealed, and delivered
in the presence of
EDWARD K. DUTTON,
41, John Dalton St.,
Manchester,
(Agent for the Patentee).
RICHARD HALLEWELL. (L.S.)