Year: 1887

page_text: Date of Application, 15th Aug., 188",
Complete Specification Left, 17th May, 1888
Complete Specification Accepted, 15th Aug., 1888
I, LOUIS SIMON DULAO, of 95 Boulevard Beaumarchais, Paris, France do hereby
declare the nature of this invention to be as follows:-
My invention relates to safety valves and has for its object to improve the construction
and increase the efficiency of said valves so that a continually uniform pressure is main-
tained in the interior of vessels upon which they are placed. The invention is based
upon the following considerations.
.
One object of the safety valve is to strictly limit the pressure of the fluid contained
in receptacles.
The ordinary valve does not fulfil this object, because the outflowing elastic fluid
experiences a very marked depression when passing from the receptacle into the
atmosphere.
This depression extends below the valve cone over a surface that becomes larger,
with the intensity increasing in proportion as the cone of the valve is lifted.
From these causes the ordinary valve, insufficient for limiting the pressure, is
reduced to the function of an indicator..
If a valve is considered during its operation it is seen that at the beginning of the
lifting the outflowing fluid acts not only upon the area of the valve for which the
charge has been calculated but also upon the annular surface upon which it rests upon
its seat. This increase of surface compensates at the beginning of the lifting for
the depression of the outflowing jet and thus keeps the valve at a small height around
its seat.
But in order to obtain a greater lifting it is obviously necessary to let intervene
either the increase of pressure or an auxiliary power designed to compensate at any
moment for the injurious action of the depression..

page_text: Independently of this former cause which limits the lifting of the valve, there exist
others and particularly the augmentation of the antagonistic charge, when this
charge is obtained by the aid of a spring, that is compressed when the valve cone
rises.
To these first two causes, separate or united, another cause, that of insufficient
lifting can be added; an eventual depression of the outflowing liquid can be produced
by the obstruction of the section for the outflow between the valve and the vessel for
generating the compressible fluid.
This is the case in certain multitubular steam boilers, thus disposed to obviate the
carrying away of water.
It is for the object of re-establishing at any moment-and, in these various cases in
practice, the equilibrium of the forces that the valve has been constructed.
The compensating part varies in form and power with the resistances which are to
be equilibrated; it is expressly composed of a socket concentric with the seat of the
valve, diverging, straight or converging according to circumstances.
A truncated prolongation diverging from the movable cone or valve, the small base
of which serves as an obstructor to the valve, and the large base of which emerges to
the exterior of the socket.
This movable element of the valve forms together with the fixed socket an annular
space of a variable angle. The annular orifice is determined by the area of the
surface of contact of the valve upon its seat. It is in fact necessary that at the
commencement of the operation the outflowing fluid shall not exert any pressure upon
the valve, the pressure of this fluid upon the annular surface by which the .cone rests
upon its seat, being sufficient to compensate for the loss of charge of the fluid which
passes out into the atmosphere. As soon as the outflow from the valve is increased
the outflowing fluid is slightly compressed in the annular space and acts upon the
valve. In proportion as the outflowing volume increases the initial and final sections
increase, but in a proportion which varies with the resistance to be compensated_for.
The greater this resistance the less rapidly increases the final section for the outflow,
the less pronounced is the angle of the movable cone or valve the more pronounced is
the angle of the socket.
These terms are reversed when the increase in the resistance is reduced to the
minimum. Action accordingly takes place upon the different variable parts of the
valve to obtain the equilibrium of the forces by following the indications hereinbefore
stated and the description of which follows.
One form of my improved valve is constructed to equilibrate at any moment the
loss of pressure which the compressible fluid experiences in its outflow. The cone is
charged either directly by a weight or by the combination of a lever with a
weight.
In case the lever is employed the latter receives its support through the medium of
a knife edge in the angle of a cross-piece; the latter is arranged in the interior of a
protecting support closed at almost its entire periphery to prevent any attempt at
wedging.
Moreover the guide in which the lever passes is formed of an elliptic ring having an
oval section which does not permit the interposition of a concealed key between the
lever and itself.
In another form of my improved compensator I enclose the same in a metallic
casing screwed upon a socket and provided with a lateral discharge pipe.
This discharge pipe is continued by a conduit of variable length that conveys the
fluid discharged through the valve. To obviate the counter pressure of the fluid in
the interior of the casing the upper part of this casing is provided with an equili-
brating valve provided with a central socket. This concentric socket at the pointed
rod contains a helical spring the base of which rests at the bottom of the socket, and
the upper part of which is compressed by the upper shoulder of the pointed rod. This
spring therefore transmits to the lever through the medium of the pointed rod an
antagonistic force equal to that which would weigh upon the valve if the outflowing
fluid were compressed in the casing....

page_text: These two forces acting in opposite directions hold each other in equilibrium, one
part of the fluid flows out through the valve and liberates the counterweight in the
outflow casing, without which the operation of the valve is paralysed by this counter
pressure.
The orifices provided in the upper shoulder of the pointed rod serve to impart to
this part a circular motion which it transmits to the valve by the lower square which
connects these two parts. The valve under pressure can thus be turned if there is any
necessity for it.
In this type of valve the projection formed upon the discharge pipe and below the
articulation of the lever renders the keeping of any wedge between the lever and
the said pipe impossible, and thus obviates all chance of the wedging of the
valve.
In another form of my improved valve the said valve not only keeps equilibrium to
the pressure of the outflowing jet of fluid, but also to the increase in the resistance
caused by the charge spring proportionally to the lifting of the movable valve.
For this purpose the large base of the movable valve cone is curved towards the
exterior so as to present to the outflowing jet a slightly concave jet. The angle of the
lower part of the cone is thin in order to augment only very insensibly the final out-
flow section of the fluid and to preserve in the annular space of the valve a sufficient
pressure to hold in equilibrium the increasing resistance of the spring. The valve can
discharge the steam into the open air or into an outflow casing having an orifice. In
the case considered the equilibrium valve is replaced by a piston having a central
orifice and sliding upon the walls of the cylinder and pointed rod. The charge spring
of any form is divided into two parts between which the piston is interposed. If the
counter pressure occurs in the casing it acts upon the piston which compresses the
upper part of the spring and discharges from the valve a quantity sensibly equal to the
counter pressure which momentarily weighs upon it.
The pointed rod emerges above the pressing nut of the spring. Its prolongation is
provided with a handle that serves to lift the cone and to impart to it a circular
motion through the medium of the lower square hereinbefore described.
The spring is of any construction; in the case used here I indicate chased discs
that are superposed and traversed by the pointed rods the base of which receives the
pressure of these discs.
In another form or modification of my improved valve in which the compensating
action acquires great energy, the valve is charged directly by a spring of the Brown
type which keeps simultaneously in equilibrium, the depression of the fluid jet passing
out into the atmosphere, the increase in the power of the spring and the depression
which the fluid undergoes, by an obstruction interposed between the valve and the
vessel in which the pressure is to be limited.
In this case the compressible fluid, after having acted upon the movable cone of the
valve, carries away the ambient air in the annular space comprised between the
cylindro-conical prolongation of the movable cone and the exterior casing. The
mixture acts by friction by reason of the velocity obtained by the movable valvo
cone, then escapes through the upper annular orifice of the casing into the
atmosphere.
The spring is compressed upon the cone by means of a cover having three arms,
which is screwed upon the upper part of the casing. This cover is provided with
a circular cavity, with which engages the prolongation of the movable cone, thus
protected against wedging.
The pointed rod is provided at its base with a square and a shoulder that receives
the extremity of the charged spring; the large base of this spring bears upon the
centre of the cover through the medium of a centreing disc. The pointed rod
traverses the central socket of the cover; its prolongation is provided with a handle
having the function herein before stated. The casing is screwed upon the part which
is the fixed body of the valve. A suitable tension of the charge spring is obtained
either by means of washers, or by screwing the cover more or less upon the casing.

page_text: .It is easily understood that the simultaneous action of the elastic fluid, escaped from
the valve and of the air compressed by this fluid upon the sides of the movable cone
gives to the valve an increase of power capable of equilibrating simultaneously the
diminished power under the valve cone and the augmented resistance above this
cone.
In the case of valves having a direct charge I construct a vertical steam dischargo
chimney screwed to the exterior of the socket and provided at its upper part with a
guide for the pointed rod. Upon this rod rests a counter-weight having a central
orifice encasing the chimney.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C,
Agents for the Applicant.

page_text: 1, LOUIS SIMON DULAC, of 95 Boulevard Beaumarchais, Paris, France, 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 safety valves and has for its object to improve the
construction and increase the efficiency of the said valves so that a continually
uniform pressure is maintained in the interior of vessels upon which they are
placed. The invention is illustrated in the accompanying drawings the figures of
which are hereinafter referred to.
The invention is based upon the following considerations.
One object of the improved safety valve is to strictly limit the pressure of the fluid
contained in receptacles.
The ordinary valve does not fulfil this object, because the outflowing elastic fluid
experiences a very marked depression when passing from the receptacle into the
atmosphere.
This depression extends below the valve cone over a surface that becomes larger,
with the intensity increasing in proportion as the cone of the valve is lifted.
From these causes the ordinary valve, insufficient for limiting the pressure, is
reduced to the function of an indicator.
If a valve is considered during its operation it is seen that at the beginning of the
lifting the outflowing fluid acts not only upon the area of the valve for which the
charge has been calculated but also upon the annular surface upon which it rests upon
its seat. This increase of surface compensates at the beginning of the lifting for
the depression of the outflowing jet and thus keeps the valve at a small height
around its seat.
But in order to obtain a greater lifting, it is obviously necessary to let intervene
either the increase of pressure or an auxiliary power designed to compensate at any
moment for the injurious action of the depression.
Independently of this former cause which limits the lifting of the valve, there
exist others and particularly the augmentation of the antagonistic charge, when this
charge is obtained by the aid of a spring that is compressed when the valve cone
rises.
To these first two causes, separate or united, another cause that of insufficient
lifting can be added; an eventual depression of the outflowing liquid can be
produced by the obstruction of the section for the outflow between the valve and the
vessel for generating the compressible fluid.
This is the case in certain multitubular steam boilers, thus disposed to obviate the
carrying away of water.
It is for the object of re-establishing at any moment and in these various cases 'n
practice, the equilibrium of the forces that the valve has been constructed.

page_text: The compensating part varies in form and power with the resistances which are to
be equilibrated; it is expressly composed of a socket A concentric with the seat of
the valve, diverging, straight or converging according to circumstances.
A truncated prolongation diverging from the movable cone or valve B the small
base of which serves as an obstructor to the valve, and the large base of which
emerges to the exterior of the socket A.
This movable element of the valve, forms together with the fixed socket A an
annular space of a variable angle. The annular orifice is determined by the area of
the surface of contact of the valve upon its seat. It is in fact necessary that at the
commencement of the operation the outflowing fluid shall not exert any pressure
upon the valve the pressure of this fluid upon the annular surface by which the core
rests upon its seat, being sufficient to compensate for the loss of charge of the fluid
which passes out into the atmosphore.
As soon as the outflow from the valve is increased the outflowing fluid is slightly
compressed in the annular space and acts upon the valve. In proportion as the
outflowing volume increases the initial and final sections increase, but in a proportion
which varies with the resistance to be compensated for.
The greater this resistance the less rapidly increases the final section for the
outflow, the less pronounced is the angle of the movable cone or valve B the more
pronounced is the angle of the socket A.
These terms are reversed when the increase in the resistance is reduced to the
minimum. Action accordingly takes place upon the different variable parts of the
valve to obtain the equilibrium of the forces by following the indications hereinbefore
stated and the description of which follows:
Figure 1 represents a valve which is uncovered, and in which the movable part B
is conical, this valve is constructed to equilibrate at any. moment the loss of pressure
which the compressible fluid experiences in its outflow. The cone is charged either
directly by a weight or by the combination of a lever J with a weight.
In case the lever J is employed the latter receives its support through the medium
of a knife edge in the angle of a crosspiece; the latter is arranged in the interior of
a protecting support closed at almost its entire periphery to prevent any attempt at
wedging.
Figure 2 represents another form of my improved valve enclosed in a metallic
casing E screwed upon a socket and provided with a lateral discharge pipe F.
This discharge pipe is continued by a conduit of variable length that conveys the
fluid discharged through the valve. To obviate the counter pressure of the fluid in
the interior of the casing E, the upper part of this casing is provided with an.
equilibrating valve provided with a central socket G. This concentric socket at the
pointed rod D contains a helical spring R the base of which rests at the bottom of
the socket, and the upper part of which is compressed by the upper shoulder of the
pointed rod D. This spring therefore transmits to the lever J through the medium
of pointed rod D an antagonistic force equal to that which would weigh upon the
valve B if the outflowing fluid were compressed in the casing E.
These two forces acting in opposite directions hold each other in equilibrium, one
part of the fluid flows out through the valve G and liberates the counter-weight in
the outflow casing, without which the operation of the valve is paralised by this
counter pressure.
The orifices provided in the upper shoulder of the pointed rod D serve to impart
to this part a circular motion which it transmits to the valve by the lower square
which connects these two parts. The valve under pressure can thus be turned if
there is any necessity for it.
In the modification represented in Figure 3 the valve not only keeps equilibrium to
the pressure of the outflowing jet of fluid, but also to the increase in the resistance
caused by the loading spring H proportionally to the lifting of the movable valve.
For this purpose the large base of the movable valve cone B is curved towards
the exterior so as to present to the outflowing jet a slightly concave jet, the angle
of the lower part of the cone is thin in order to augment only very insensibly the

page_text: final outflow section of the fluid and to preserve in the annular space of the valve
a sufficient pressure to hold in equilibrium the increasing resistance of the spring.
The valve can discharge the steain into the open air or into an outflow casing E
having an orifice. In the case considered the equilibrium valve is replaced by a
piston I having a central orifice and sliding upon the walls of the cylinder G and
pointed rod D. The charge spring H of any form is divided into two parts between
which the piston I is interposed; if the counter pressure occurs in the casing E it
acts upon the piston I which compresses the upper part of the spring H and dis-
charges from the valve a quantity sensibly equal to the counter pressure which
momentarily weighs upon it.
The pointed rod D emerges above the pressing nut of the spring, its prolongation
is provided with a handle K that serves to lift the cone and to impart to it a
circular motion through the medium of the lower square hereinbefore described.
The spring is of any construction in the case used here we indicate chased discs
that are superposed and traversed by the pointed rods D, the base of which receives
the pressure of these discs.
In the form or modification of my improved valve represented in Figure 4 in which
the compensating action acquires great energy, the valve is charged directly by a
spring H of the Brown type which keeps simultaneously in equilibrium, the depression
of the fluid jet passing out into the atmosphere, the increase in the power of the
spring and the depression which the fluid undergoes, by an obstruction interposed
between the valve and the vessel in which the pressure is to be limited.
In this case the compressible fluid, after having acted upon the movable cone B of
the valve carries away the ambient air in the annular space comprised between the.
cylinders, conical prolongation of the movable cone B and the exterior casing E. The
mixture acts by friction by reason of the velocity obtained by the movable valve
cone B, then escapes through the upper annular orifice of the casing E into the
atmosphere.
.
The spring is compressed upon the cone by means of a cover having three arms G,
which is screwed upon the upper part of the casing E.
This cover is provided
with a circular cavity with which engages the prolongation of the movable cone B,
thus protected against wedging.
The pointed rod D is provided at its base with a square and a shoulder that receives
the extremity of the charge spring; the large base of this spring bears upon the.
centre of the cover through the medium of a centering disc M. The pointed rod D
traverses the central socket of the cover G, its prolongation is provided with a
handle K having the function hereinbefore stated. The casing E is screwed upon
the part A, which is the fixed body of the valve. A suitable tension of the charge
spring is obtained either by means of washers L or by screwing the cover G more
or less upon the casing E. It is easily understood that the simultaneous action of the
elastic fluid, escaped from the valve and of the air compressed by this fluid upon the
sides of the movable cone B gives to the valve an increase of power capable of
equilibrating simultaneously the diminished power under the valve cone and the
augmented resistance above this cone.
In the case of valves having a direct charge I construct a vertical steam discharge
chimney screwed to the exterior of the socket A and provided at its upper part with a
guide for the pointed rod. Upon this rod rests a counter weight having a central
orifice encasing the chimney.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed 1 declare that what
1 claim is:-
First. The employment in safety valves having a direct load by a counter weight
or by a spring, or a load by a combination of levers with a counterweight or spring,
of a valve obtained by the conic or divergent form of the part which surmounts
the cone of the valve in combination with a concentric socket having straight,
converging, curved, or diverging sides as and for the purpose, set forth.

page_text: Second. In safety valves having casings, the employment of an equilibrium valve
cone or of a piston with the object of compensating for the counter pressure, as above
described.
Third. In safety valves having a compensation or valve proper the prolongation of
the movable part of the said valve and its combination with an external casing for the
purpose of utilizing the carrying away of the air by the outflowing fluid as above
described.
Fourth. The general and detail arrangements of the safety valves and in particular
those constructed for the purpose of preventing the wedging of the valve, as described
and represented in the annexed drawings.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,.
Agents for the Applicant.