Improvements in and relating to Evaporating Apparatus.
Year: 1893

page_text: Date of Application. 4th Nov., 1893
Complete Specification Left, 31st July, 1894-Accepted, 3rd Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in and relating to Evaporating Apparatus.
1, PAUL DOUDART DE LA GRÉE, of 95 Boulevard Beaumarchais, Paris, in
the Republic of France, Barrister, do hereby declare the nature of this invention
to be as follows:--
My invention relates to apparatus for instantaneously evaporating water, and
has for its object to obviate swamping by preventing the passage of the water
into the serpentine used when the latter is not sufficiently heated.
As is well known the apparatus heretofore used for instantaneously evaporating
water present the serious inconvenience of being swamped by the feed water when
the heating is not sufficient for completely transforming the feed water into
steam.
°
This inconvenience occurs more especially when the evaporating apparatus
comprises several connected or unconnected elements, for in this case it is very
difficult to regulate the heating so as to distribute the heat uniformly to all the
elements and to maintain it at the desired temperature for the evaporation, unless
more fuel be used than is necessary.
In order to obviate this inconvenience and to completely avoid the swamping it
is evident that it will be sufficient to prevent the passage of the feed water to the
serpentine each time when the latter is not at a sufficiently high temperature for
completely evaporating the water which traverses it, and to afford on the other
hand access to the feed water when the temperature of the apparatus or of the
element considered is sufficient for evaporating the same.
But the operation
of the valve or the like which closes the feed water pipes or opens the return
water pipe, or stops the operation of the pump, which amounts to the same
thing, should, if the swamping is to be completely obviated, take place
automatically when the temperature of the element is no longer sufficient for
causing the evaporation, for, as will be easily understood, it is impossible to know
or to foresee the variations of temperature of one of the elements of the apparatus
in order to actuate at the precise movement the valve or the like for closing the
feed water pipe.
I have been led to consider the variations of temperature of the evaporating
apparatus with a view of imparting to the valve or the like the movements which
are required for opening or closing at the desired moments either the water inlet
pipe or the return water pipe or for stopping the operation of the pump. By my
said invention I am enabled to automatically regulate the admission of the feed
water to the apparatus for instantaneous evaporation, whether such apparatus are
composed of a single element or of several elements, by means of the variations of
temperature of these apparatus so that the admission of the water is interrupted
when the temperature of the elements or of each element considered is not
sufficient for evaporating the feed water and that on the contrary the water is
admitted when the temperature is sufficient for the evaporation.
For establishing a mechanical relation between the degree of temperature of the
apparatus and the valve or the like for closing the inlet of the feed water or the
return water I may employ the devices hereinafter described by way of
example.
At a point of the element, the swamping of which is to be prevented, and which
is not subjected directly to the action of the flame of the furnace, that is to say at

page_text: a point where it receives the heat of the element itself or the steam which it
produces, I arrange a receptacle of small dimensions so as to be surrounded by
the element, leaving on its sides a passage sufficient for the water injected into the
element or for the steam which it has produced.
This receptacle is open at its upper part upon which may be screwed a cap
which closes it completely.
An inclined tube, almost capillary or of a very small diameter, sets the aforesaid
receptacle in communication with a casing or chamber of elastic material which
can lengthen and shorten. This chamber of elastic material is placed in a cylinder
above a piston which can move with little friction in the cylinder. The upper
edge of the elastic chamber is clamped between the cylinder and its cap from which
the above-mentioned tube extends.
A spring which may be regulated at will resists the movement of the piston.
Before subjecting the evaporating element to heat I introduce into the receptacle,
through the opening closed by the aforesaid cap, a small quantity of water so as
to fill this receptacle, the small tube and the elastic chamber which is then
reduced to its minimum capacity.
When the element is now subjected to heat its temperature is gradually raised
and communicated by conductibility to a point of this element where the said
receptacle is placed, which latter is arranged so as not to receive the action of
the flame directly. The temperature of the receptacle will be raised at the same
time as that of the element, and when it has reached or exceeded 100 degrees the
water contained in the receptacle is transformed into steam which, having no
outlet, will simply act upon the sides of the elastic chamber and enlarge this
chamber when the pressure of the steam is sufficient to overcome the action of
the before-mentioned spring. As the chamber enlarges it presses against the
piston and causes the piston rod to move downwards.
•
If at a given moment from any cause the temperature of the element is lowered,
the steam produced in the receptacle will gradually condense and a moment will
arrive when its action against the bottom of the elastic chamber will no longer be
sufficient for counterbalancing the action of the spring, which will then compel
the piston and its rod to move upwards.
It will be seen that to an augmentation of temperature of the element
corresponds a displacement of the rod of the piston in one direction, and that to a
diminution of this temperature corresponds a displacement of the piston in the
other direction.
In order to obtain the automatic regulation of the admission of feed water to the
element by means of variations of temperature of the latter it is therefore
sufficient to connect the piston rod, by any suitable intermediate parts, with the
flap, disc, cone, slide valve or the like which controls the inlet of the water into
the serpentine or the water return pipe or the operation of the pump, the
connection between the piston rod and one of these valves or the like being
established in such a manner that the displacement of the piston rod in one
direction, corresponding to a temperature of the element sufficient for the
evaporation, permits the admission of the water and that on the contrary the
displacement of the piston rod in the other direction, corresponding to a
temperature of the element insufficient for the evaporation, completely shuts off the
feed water from the element.
For ensuring the good operation of my apparatus it will be sufficient to regulate
the tension of the spring in such a manner that the valve or the like set in motion
by the piston rod permits the admission of the water only at the moment when the
temperature is sufficient for the evaporation and that it prevents the admission of
the water as soon as this temperature has reached the minimum degree below
which the evaporations would no longer take place.
In order that the operation of the element may not only be permitted when the
latter is in a state of very high temperature it may be expedient to interrupt the
admission of the feed water only when already a portion of the element is filled

page_text: with unevaporated water. It might happen in this case that when the heating be
again increased and the extremity of the element obstructed by any device this
quantity of water converted into steam would rise to abnormal pressures.
To obviate this inconvenience it will be sufficient to place upon this element a
small safety valve rejecting the water either to the outside or into the return
water pipe, but in case the regulating valve or the like controls either the
serpentine or the water return pipe it is much simpler to place upon this part a
ball, flap or other suitable valve which will be closed under any pressure tending
to enter the element of the generator, and will on the contrary open under any
pressure coming from the interior of this element. If for example the regulating
device consists of a slide valve obstructing or uncovering the inlet of the element
this valve is placed upon the said slide valve.
Dated this 4th day of November 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in and relating to Evaporating Apparatus.
I, PAUL DOUDART DE LA GREE, of 95 Boulevard Beaumarchais Paris, in the
Republic of France, Barrister, do hereby declare the nature of this invention, and
in what manner the same is to be performed, to be particularly described and
ascertained, in and by the following statement :-
:-
My invention relates to apparatus for instantaneously evaporating water, and has
for its object to obviate swamping by preventing the passage of the water into the
serpentine used when the latter is not sufficiently heated.
As
My invention relates to apparatus for instantaneously evaporating water.
is well known, apparatus heretofore used present the serious inconvenience of
being swamped by the feed water when the heating is not sufficient to completely
transform the feed water into steam.
"This inconvenience occurs more especially when the evaporating apparatus
comprises several connected or unconnected elements, for in this case it is very
difficult to regulate the heating so as to distribute the heat uniformly to all the
elements and to maintain it at the desired temperature for evaporation, unless more
fuel be used than is necessary.
In order to obviate this inconvenience and to completely avoid the swamping it
is evident that it will be sufficient to prevent the passage of the feed water to the
serpentine each time when the latter is not at a sufficiently high temperature for
completely evaporating the water which traverses it, and to afford on the other"
hand access to the feed water when the temperature of the apparatus or of the
element considered is sufficient for evaporating the same. But the operation of
the valve or the like which closes the feed water pipe, or opens the return water
pipe, or stops the operation of the pump, which amounts to the same thing, should,
if the swamping is to be completely obviated, take place automatically when the
temperature of the element is no longer sufficient for causing the evaporation, for,
as will be easily understood, it is impossible to know or to foresee the variations of
temperature of one of the elements of the apparatus in order to actuate at the
precise moment the valve or the like for closing the feed water pipe.
I have been led to consider the variations of temperature of the evaporating
apparatus with a view of imparting to the valve or the like the movements which
are required for opening or closing at the desired moments, either the water inlet
pipe or the return water pipe or for stopping the operation of the pump. By my
said invention I am enabled to automatically regulate the admission of the feed
water to the apparatus for instantaneous evaporation, whether such apparatus are
composed of a single element or of several elements, by means of the variations of

page_text: temperature of these apparatus so that the admission of the water is interrupted
when the temperature of the elements or of each element considered is not sufficient
for evaporating the feed water and that on the contrary the water is admitted when
the temperature is sufficient for the evaporation.
For establishing a mechanical relation between the degree of temperature of the
apparatus and the valve or the like for closing the inlet of the feed water, or the
return water I may employ the devices hereinafter described by way of example,
and illustrated in the accompanying drawings in which
Figure 1 illustrates in sectional view the apparatus for working the regulating
device.
Figure 2 is a sectional view illustrating the regulating device.
At a point of the element A, the swamping of which is to be prevented, and
which is not subjected directly to the action of the flame of the furnace, that is to
say at a point where it receives the heat of the element itself or the steam which
it produces I arrange a receptacle B Figure 1, of small dimensions so as to be
surrounded by the element, leaving on its sides a passage sufficient for the water
injected into the element or for the steam which it has produced.
This receptacle is open at its upper part upon which is screwed a cap C which
closes it completely.
An inclined tube D, almost capillary or of a very small diameter, puts the
aforesaid receptacle B in communication with a casing or chamber E of elastic
material which can-lengthen and shorten. This flexible chamber is placed in a
cylinder F above a piston G which can move with little friction in the cylinder.
The upper edge of the flexible chamber is clamped between the cylinder and its
cap from which the above-mentioned tube D extends.
A spring I surrounding the piston rod H and which may be regulated at will
resists the movement of the piston.
Before subjecting the evaporating element to heat I introduce into the
receptacle B through the opening closed by the aforesaid cap C a small quantity
of water so as to fill this receptacle, the small tube D and the flexible chamber É
which is then reduced to its minimum capacity.
When the element A is now subjected to heat its temperature is gradually
raised and communicated by conductibility to a point of this element where the
said receptacle B is placed, which latter is arranged so as not to receive the
action of the flame directly. The temperature of the receptacle B will be raised
at the same time as that of the element, and when it has reached or exceeded
100 degrees the water contained in the receptacle is transformed into steam which,
having no outlet, will simply act upon the sides of the elastic chamber E and
enlarge this chamber when the pressure of the steam is sufficient to overcome the
action of the before-mentioned spring I. As the chamber enlarges it presses
against the piston G and causes the piston rod H to move downwards.
If at a given moment from any cause the temperature of the element is lowered,
the steam produced in the receptacle B will gradually condense and a moment will
arrive when its, action against the bottom of the elastic chamber will no longer be
sufficient to counterbalance the action of the spring, which will then compel the
piston G and its rod H to move upwards.
It will be seen that to an augmentation of temperature of the element
corresponds a displacement of the rod of the piston G in one direction, and that
to a diminution of this temperature corresponds a displacement of the piston in
the other direction.
In order to obtain the automatic regulation of the admission of feed water to
the element by means of variations of temperature of the latter it is therefore
sufficient to connect the piston rod H, by any suitable intermediate parts with the
flap, disc, cone, slide valve or the like which controls the inlet of the water into
the serpentine or the water return pipe or the operation of the pump, the
connection between the piston rod H and one of these valves or the like being
established in such a manner that the displacement of the piston rod H in one

page_text: direction, corresponding to a temperature of the element sufficient for the
evaporation, permits the admission of the water and that on the contrary the
displacement of the piston rod in the other direction, corresponding to a temperature
of the element insufficient for evaporation, completely shuts off the feed water
from the element.
For ensuring the good operation of my apparatus it will be sufficient to regulate
the tension of the spring I in such a manner that the valve or the like set in
motion by the piston rod H permits the admission of the water only at the moment
when the temperature is sufficient for the evaporation and that it prevents the
admission of the water as soon as this temperature has reached the minimum degree.
below which the evaporations would no longer take place.
In practice the apparatus will be regulated for stopping the access of the feed
only when a portion of the element is already provided with unevaporated water,
that is to say, the flap, valve or the like will be regulated for completely closing
the admission of water only when the temperature is slightly lower than that.
necessary for the vaporization. In order, under these conditions, to prevent the
pressure in the element becoming too great when the heating again takes place,.
should the extremity of the element be accidentally plugged, I employ the following
arrangement.
Upon this element I place a small safety valve ejecting the water either to the
outside or into the return water pipe, but in case the regulating valve or the like
controls either the serpentine or the water return pipe L it is much simpler to
place upon this part a ball, flap or other suitable valve J which will be closed
under any pressure tending to enter the element of the generator, and will on the
contrary open under any pressure coming from the interior of this element. If
for example the regulating device consists of a slide valve K controlling the
inlet of the element A this valve J is placed upon the slide valve as shown in.
Figure 2.
Having now particularly described and ascertained the nature of my said inven--
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
The automatic regulation of the inlet of the feed water into an instantaneous.
evaporating apparatus, whether such apparatus be composed of one or more
elements, by means of the variations of temperature of the apparatus and in such
a manner that the inlet of the water into the elements or each of them separately
is stopped when the temperature of these elements or of the element considered is.
not sufficient for evaporating the feed water, and on the contrary the inlet of the
water is allowed when the temperature is sufficient for evaporation, the inlet of the
water into the serpentine being prevented by causing the variations of temperature,
as hereinabove set forth by way of example, to act upon a slide flap, or other
valve placed in the water inlet pipe, or by causing said variations to act upon a
valve placed in the return water pipe or by causing them to act directly upon the
feed pump, so that the latter stops when the temperature is insufficient for
evaporation, and operates when the temperature has again attained the desired
degree.
D
1
1
CTI
1004
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant..