AN IMPROVED MODE OF RECOVERING AND REGENERATING STEAM IN MOTIVE-POWER ENGINES, AND APPARATUS THEREFOR.
Year: 1872

page_text: LETTERS PATENT to François Maurice Hippolyte Motard, of Ruc
Gaillon, No. 5, à Paris, Engineer, for the Invention of "AN IMPROVED
MODE OF RECOVERING AND REGENERATING STEAM IN MOTIVE-POWER ENGINES,
AND APPARATUS THEREFOR.'
"
Scaled the 24th January 1873, and dated the 6th August 1872.
PROVISIONAL SPECIFICATION left by the said François Maurice
Hippolyte Motard at the Office of the Commissioners of Patents,
with his Petition, on the 6th August 1872.
I FRANÇOIS MAURICE HIPPOLYTE MOTARD, of Rue Gaillon, No. 5, à
Paris, Engineer, do hereby declare the nature of the said Invention
for "AN IMPROVED MODE OF RECOVERING AND REGENERATING STEAM IN MOTIVE-
POWER ENGINES, AND APPARATUS THEREFOR," to be as follows:-
1
It is known that in employing steam in engines the latent heat com-
municated to it in the boiler when the water is converted into vapour
is totally lost when the steam escapes into the atmosphere, and that it is
last to a great extent when the steam is condensed. Hence results an
excessive consumption of fuel, which is the more objectionable as fuel
becomes daily more rare and expensive. To remedy this defect many.

page_text: plans have been proposed, which, though ingenious, nave nituerto fallca
in practice. I hope to be more successful with the system which I
have devised for this purpose, and which forms the subject of my present
Invention.
The problem which I have solved may be thus stated :—
1st. To collect in whole or in part the steam remaining on the side of
the piston towards which it is moving in the condition of dilatation, to
which it has been brought by expansion in the cylinder.
2dly. To regenerate or recover this steam, that is to say, while
retaining it in the gaseous condition, to restore to it the normal tension
which it had before reaching the cylinder in such a manner that on
admitting it again to the cylinder it shall there perform the same
mechanical work as it had done before.
In order to fulfil these conditions I have had recourse to a physical
principle, of which the application made by me is marked at once by the
novelty of the object to be attained, and by the originality of the
arrangements and apparatus employed for this purpose. This principle
consists in the well known property which a fluid mass in movement
possesses of sucking or drawing with it in its passage a surrounding fluid
mass relatively in a state of rest, the two masses forming by their
mixture a single resultant, the uniform physical nature of which partakes
of those of the two constituent masses. Indeed my system consists
essentially in the introduction of a jet of steam from a generator at
higher pressure than that of the steam admitted to the cylinder, which
jet is directed through the mass of steam expanded after performing
work in a medium selected outside the cylinder in the course of the
exhaust pipe. This jet, in its rapid passage, encountering the expanded
steam forms a new current, which acts according to the special conditions
resulting from the new elements introduced, a pressure and temperature
exceeding those of the expanded steam.
The second point characteristic of my system is the arrangement of a
reservoir for receiving the current produced, and for delivering successive
charges to the cylinder, which is thus supplied with steam from this
reservoir, and not from the boiler to which the fire is applied.
It will be seen that the economy of fuel obtained depends on the
quantity of steam expended in producing the jet. That this quantity

page_text: may be the smallest possible, I have found that it must be in a super-
heated state, that is to say, heated to a temperature considerably.
exceeding that which is due to saturated steam of equivalent pressure.;
In fact, the complex and intermediate phenomena which manifest them-
5 selves on the mixture of the two masses of steam result finally in a
mutual exchange of their quantities of heat. Thus when the equilibrum
- of temperature is attained the weight of steam to be introduced as jet
"may be estimated by the simple formula of mixture, so that it can be
readily determined that the higher the temperature of the steam forming.
the jet the less weight of it is required. In this formula it is to be
remarked that pressure forms no element, but it necesserily must exceed
that of the regenerated steam, in order to give the current which it
forms sufficient energy to overcome the resistance of the medium formed
in the exhaust chamber. Thus high temperature and pressure exceeding,
that in the chamber are the two elements which should be brought by:
the steam of the jet in order to constitute afresh the expanded steam,.
and to add to the heat which it retains the quantity of heat which it had:
lost in doing work.
It cannot fail to be remarked that the chamber in receiving the
resulting current will necessarily be charged with an excess of fluid
from the jet, which excess is not required to be expended in the cylinder..
To avoid surcharge I can discharge the excess of steam either by the
chimney to assist the draught, or by employing it to work a small,
engine. I prefer, however, the following mode of utilising it :-It is;
founded on this observation, that it is better to promote the condensation,
of the jet steam in the chamber in order to get full advantage of all its
latent heat than to let it escape and make use of it in the gascous
condition. Consequently, in order to force this steam to condense, I'
bring the current immediately after its formation in the selected medium
in-contact with a thin stream of water, sucked in in such a manner that
the regenerated steam shall alone retain the qualities of an elastic fluid
when it reaches the interior of the chamber. This chamber will there-
fore always contain a certain quantity of water of condensation, which
will be retained at a constant level, and which will be returned as heated
feed water to the boiler, restoring to it to a great extent the heat brought
in excess to the current. It may therefore be said of the chamber that
it will perform the office of regenerator of the second order and of feed
heater.

page_text: Having thus explained generally the physical conditions on which my
system of operating is founded, I will now describe the combination and
arrangement of apparatus by which it is carried into practical effect,
referring to the accompanying Sheet of Drawings, and to the figures and
letters marked thereon.
Fig. 1 represents a side view of a locomotive with my system applied
to it, and Fig. 2 represents a longitudinal section of the apparatus for
producing the fluid current.
A is the steam or exhaust chamber placed above the boiler B, with
which it has no communication. The boiler is provided with a super-
heater which superheats the steam before it is collected in the dome C.
The apparatus D for producing the currcut is arranged between the
chamber A and the boiler dome C, at a little distance from the working
steam cylinder F. The steam for forming the jet flows from the dome
by the pipe a, which is provided with a cock b, and has a nozzle c above
the sucking tubej, which is an extension of the waste steam pipe, and
brings the expanded steam from the cylinder. The current formed
passes through a taper tube e, the position of which can be ascertained
by inspection through a hole n, and can be altered by a pinion p
gearing with a rack q on the tube so as to adjust the areas of entrance
into and issue from the tube c. A pipe k brings the water for con-
densing the steam of the jet after it has effected its purpose. This water
passing through lateral holes in the tube e mixes with the current in
the tube, and the mingled current enters the expanding tube f, the arca
of the mouth of which can be regulated by a taper spindle g. For this
purpose the spindle g has on it a screw thread working in the body of
the apparatus D, and is provided with a wheel and handle o, by turning
which the spindle can be made to advance or recede. A stuffing box i
prevents escape of steam or water round the spindle. The pipe m,
branching upwards over the expanding tube f, serves to prime the
apparatus, and to permit free discharge of the steam in case the current
should by any circumstance be arrested. The excess of water can issue
by the pipe branching downwards. The current after raising a check
valve at flows by the piper into the exhaust chamber or second
generator A.
In this chamber the current on arriving proceeds to
separate itself into its two constituent parts, steam and water. Of the
one part, the quantity of expanded steam which has been regenerated
diffuses itself through the chamber, putting itself in equilibrium with

page_text: the existing medium, which has the initial pressure of the exhaust
steam. Of the other part, the water resulting from the condensation of
the jet mingled with the water introduced for the condensation falls to
the bottom of the chamber and constitutes the reserve of liquid for
maintaining the steam in a saturated condition. A pump or other feed
apparatus draws this hot water for feeding the boiler. In order to
maintain its level constant, a cock acted on by a float may be employed
to discharge automatically the excess of water.
In starting the apparatus the chamber A must be filled, which can bo
done by opening for a short time a cocks on a small pipe t, which takes
steam directly from the boiler.
In carrying out these improvements it will, be understood that the
proportions and details of the apparatus may be varied without departing
from the essential features of the Invention; which may be classed as
follows:-
1. The regeneration of the steam expanded in a working cylinder by
restoring to it the heat and pressure expended in doing work by means
of superheated steam of a pressure higher than that of the working
steam.
2. The use of the regenerating steam for drawing the expanded steam
into a medium selected outside of the cylinder in the course of the
exhaust pipe.
T
3. The special apparatus for effecting the regeneration of the expanded
steam, by incorporating it in the form of a fluid current with the steam
of the regenerating jet.
4. The action of the internal parts of the apparatus in forming the
fluid current, and directing it into a reservoir of steam after the intro-
duction into the current of the quantity of water necessary to condenso
the steam of the jet.
5. The arrangement of a steam reservoir serving for the supply of
the cylinder with the regenerated steam, and acting at the same time as
a generator of the second order, and as a feed heater.
6. The general combination, as above described in reference to the
annexed Drawings, for the fulfilment of the conditions that have been
hercin-before explained.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said François Maurice Hippolyte Motard in the Great
Seal Patent Office on the 28th January 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANÇOIS
MAURICE HIPPOLYTE MOTARD, of Rue Gaillon, No. 5, à Paris, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of August, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said François Maurice Hippolyte Motard, Her
special license that I, the said François Maurice Hippolyte Motard,
my executors, administrators, and assigns, or such others as I, the said
François Maurice Hippolyte Motard, my executors, 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 "AN IMPROVED MODE OF RECOVERING
AND REGENERATING STEAM IN MOTIVE-POWER ENGINES AND APPARATUS THERE-
FOR," upon the condition (amongst others) that I, the said François
Maurice Hippolyte Motard, my executors or administrators, by an
instrument in writing under my, or their, or one of 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 be 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 I, the said François Maurice Hippolyte Motard,
do hereby declare the nature of the 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, reference being had to the
accompanying Sheet of Drawings, and to the figures and letters marked
thercon, that is to say :-
It is known that in employing steam in engines the latent heat com-
municated to it in the boiler when the water is converted into vapour is

page_text: otally lost when the steam escapes into the atmosphere, and that it is
ost to a great extent when the steam is condensed. Hence results an
xcessive consumption of fuel, which is the more objectionable as fuel
ecomes daily more rare and expensive. To romedy this defect many
lans have been proposed, which, though ingenious, have hitherto failed
practice. I hope to be more successful with the system which I have
evised for this purpose, and which forms the subject of my present.
"
excessive consumption of fuel, which is the more objectionable as fuel
becomes daily more rare and expensive. To romedy this defect many
plans have been proposed, which, though ingenious, have hitherto failed
in practice. I hope to be more successful with the system which I have
devised for this purpose, and which forms the subject of my present.
Invention.
The problem which I have solved may be thus stated :—
1st. To collect in whole or in part the steam remaining on the side of
the piston towards which it is moving in the condition of dilatation to
which it has been brought by expansion in the cylinder..
2ndly. To regenerate or recover this steam, that is to say, while
retaining it in the gascous condition to restore to it the normal tension..
which it had before reaching the cylinder, in such a manner that on.
admitting it again to the cylinder it shall there perform the same
mechanical work as it had done before.
In order to fulfil these conditions I have had recourse to a physical
principle, of which the application made by me is marked at once by the
novelty of the object to be attained, and by the originality of the arrange-
ments and apparatus employed for this purpose. This principle consists
in the well known property which a fluid mass in movement possesses
of sucking or drawing with it in its passage a surrounding fluid mass
relatively in a state of rest, the two masses forming by their mixture a
single resultant, the uniform physical nature of which partakes of those
of the two constituent masses. Indeed, my system consists essentially
in the introduction of a jet of superheated steam from a generator at
higher pressure than that of the steam admitted to the cylinder, which
jet is directed through the mass of steam expanded after performing
work, in a medium selected outside the cylinder in the course of the
escape pipe. This jet in its rapid passage encountering the expanded
steam forms a new current, which acts according to the special conditions
resulting from the new elements introduced a pressure and temperature.
exceeding those of the expanded steam.
The second point characteristic of my system is the arrangement of a
chamber or reservoir for receiving the current produced, and for
delivering successive charges to the cylinder, which is thus supplied
.

page_text: with steam from this reservoir and not from the boiler to which the fire
is applied.
It will be seen that the economy of fuel attained depends on the
quantity of steam expended in producing the jet; and in order that this
quantity may be the smallest possible, I have found that it must be in a
superlicated state, that is to say, heated to a temperature considerably
exceeding that which is due to saturated steam of equivalent pressure.
In fact the complex and intermediate phenomena which manifest them-
selves on the mixture of the two masses of steam result finally in a
mutual exchange of their quantities of heat. Thus when the equilibrium
of temperature is attained the weight of steam to be introduced as jet
may be estimated by the simple formula of mixture, so that it can be
readily determined that the higher the temperature of the steam forming
the jet the less weight of it is required. In this formula it is to be
remarked that pressure forms no element, but it necessarily must exceed
that of the regenerated steam, in order to give the current which it forms
sufficient energy to overcome the resistance of the medium formed in
the admission chamber. Thus high temperature and pressure exceeding
that in the chamber are the two elements which should be brought by
the steam of the jet in order to constitute afresh the expanded steam,
and to add to the heat which it retains the quantity of heat which it had
lost in doing work.
It cannot fail to be remarked that the chamber in receiving the
resulting current will necessarily be charged with an excess of fluid
from the jet, which excess is not required to be expended in the cylinder.
To avoid surcharge I can discharge the excess of steam either by the
chimney, to assist the draught, or by employing it to work a small
engine. I prefer, however, the following mode of utilising it :-It is
founded on this observation, that it is better to promote the condensation
of the jet steam in the chamber in order to get full advantage of all its
latent heat than to let it escape and make use of it in the gascous
condition. Consequently, in order to force this steam to condense I
bring the current, immediately after its formation in the selected medium,
in contact with a thin stream of water sucked in in such a manner that
the regenerated steam shall alone retain the qualities of an elastic fluid
when it reaches the interior of the chamber. This chamber will, there-
fore, always contain a certain quantity of water of condensation, which
will be retained at a constant level, and which will be returned as heated

page_text: feed water to the boiler, restoring to it to a great extent the heat brought
in excess to the current. It may therefore be said of the chamber that
it will perform the office of regenerator of the second order and of feed
heater.
Having thus explained generally the physical conditions on which my
system of operating is founded, I will now describe the combination and
arrangement of apparatus by which it is carried into practical effect,
referring to the accompanying Sheet of Drawing, and to the figures and
letters marked thereon.
:
Fig. 1 represents a side view of a locomotive with my system applied
to it, and Fig. 2 represents a longitudinal section of the apparatus for
producing the fluid current.
A is the steam or escape chamber placed above the boiler B, with
which it has no communication. The boiler is provided with a super-
lieater which superheats the steam before it is collected in the dome C.
The apparatus D for producing the current is arranged between the
chamber A and the boiler dome C, at a little distance from the working
steam cylinder. The steam for forming the jet flows from the dome by
the pipe a, which is provided with a cock 6, and has a nozzle c above the
sucking tube j, which is an extension of the waste steam pipe, and
brings the expanded steam from the cylinder. The current formed
passes through a taper tube e, the position of which can be ascer-
tained by inspection through a hole n, and can be altered by means
of a pinion p gearing with a rack q on the tube, so as to adjust
the areas of entrance into and issue from the tube e. A pipe / brings
the water for condensing the steam of the jet after it has effected its
purpose. This water passing through lateral holes in the tube.e' mixes
with the current in the 'tube, and the mingled current enters the
expanding tube, the area of the mouth of which can be regulated by a
taper spindle g. For this purpose the spindle has on it a screw thread
working in the body of the apparatus D, and is provided with a wheel
and handle o, by turning which the spindle can be made to advance or
recede. A stuffing box i prevents escape of steam or water round the
spindle. The pipe m, branching upwards over the expanding tube ƒ
serves to prime the apparatus, and to permit free discharge of the steam.
in case the current should by any circumstance be arrested. The excess
of water can issue by the pipe branching downwards. The current,

page_text: after raising a check valve at h, flows by the piper into the admission
chamber or second generator A. In the chamber the current on arriving
proceeds to separate itself into its two constituent parts, steam and
water. Of the one part, the quantity of expanded steam which has
been regenerated diffuses itself through the chamber, putting itself in 5
equilibrium with the existing medium, which has the initial pressure of
the admission steam. Of the other part, the water resulting from the
condensation of the jet, mingled with the water introduced for the con-
densation, falls to the bottom of the chamber, and constitutes the reserve
of liquid for maintaining the steam in a saturated condition. A pump 1
or other feed apparatus draws the hot water for feeding the boiler. In
order to maintain its level constant a cock acted on by a float may be
cmployed to discharge automatically the excess of water.
In starting the apparatus the chamber A must be filled, which can be.
done by opening for a short time a cock s on a small pipe t, which takes 1
steam directly from the boiler.
In some cases the chamber A may be dispensed with, the current
containing the regenerated steam being led from the apparatus D directly
into the boiler.
In carrying out these improvements. it will be understood that the 2
proportions and details of the apparatus may be varied without departing
from the essential features of the Invention, which may be classed as
follows:
1. The regeneration of the steam expanded in a working cylinder, by
restoring to it the heat and pressure expended in doing work, by means 2
of suplierheated steam of a pressure higher than that of the working
steam, substantially as herein described.
2. The use of this regenerating steam for drawing the expanded steam
into a medium selected outside of the cylinder in the course of the
escape pipe, substantially as herein described.
3. The use of apparatus constructed and acting substantially as heroin
described, for effecting the regeneration of the expanded steam by
incorporating it in the form of a fluid current with the steam of the
regenerating jet.
3
4. The action of the said apparatus in forming the fluid current and 35
directing it into a reservoir of steam after the introduction into the

page_text: current of the quantity of water necessary to condense the steam of the
jet, substantially as herein described.
5. The arrangement of a steam chamber or reservoir serving for the
supply of the cylinder with the regenerated steam, and acting at the
same time as a generator of the second order and as a feed heater, sub-
stantially as herein described.
6. The general combination, substantially as herein described in
reference to the annexed Drawings, of regenerating apparatus with the
boiler and working cylinder of a steam engine.
. In witness whereof, I, the said François Maurice Hippolyte Motard,
have hereunto set my hand and seal, this Eighteenth day of
January, in the year of our Lord One thousand eight hundred and
seventy-three.
15 Witness,
F. M. H. MOTARD. (L.S.)
ALBERT CAHEN,
Civil Engineer,
No. 32, Boulevard Magenta,
at Paris.