Improvements in Incandescent Oil Lamps.
Year: 1897

page_text: Improvements in Incandescent Oil Lamps.
I, LEOPOLD RALPH ATILENOR MOREL, of 57, Boulevard Pereire, Paris, France,
Engineer, do hereby declare the nature of this invention to he as follows:-
This invention relates to incandescent oil lamps and consists essentially in the
means of maintaining a constant blue flame. The apparatus hitherto constructed
for incandescent lighting by the vapourization of petroleum from a wick, possess
the two-fold objection of being difficult to ignite while the blue flame produced is
wanting in stability. In these lamps the two surfaces of the wick are exposed to
currents of air of different velocities and having different temperatures. The inner
surface of the wick receives a current of air of low velocity which furnishes a
sufficient volume of hot air to support combustion while its outer surface receives
a current of air of accelerated velocity which serves to carry upwards the petroleum
vapours which are disengaged from the outer and upper surfaces of the wick.
The wick consequently only remains alight on its inner surface there being no
flame on its upper and on its outer surfaces from which the vapourization of the
petroleum is maintained by the heat afforded by the combustion of the petroleum
on the interior surface of the wick. The mixture of air and vapours carried off
ignites only at a certain distance above the wick and if the mixture is in suitable
proportions the combustion is complete, the flame is blue, and the heat of com-
bustion is sufficient to maintain an Auer mantle perfectly incandescent. When
the blue flame is stable it may be concluded that the velocity of propagation of the
flame in the combustible mixture is equal to the velocity of flow of said mixture.
But this equilibrium which is analogous to that of a ball on a jet of water, may be
destroyed by many causes and more especially by the two following:-
1st. The excessive heating of the ascending current which tends to increase in
a preponderating manner the velocity of propagation in a downward direction.
2nd. Any vibration imparted to the air around the lamp, in which case waves
alternately accelerated and retarded are produced. At the moment of passing of
the wave of diminished velocity, the velocity of propagation of the flame becomes
higher than that of the flow of the mixture and the flame descends to the upper
edge of the wick.
The presence of the mantle still further diminishes the stability of the flame,

page_text: this influence being such that certain arrangements which ensure a stable blue
flame which is almost insensible to external disturbances, do not allow of a
mantle being used; moreover if the blue flame in a heating lamp presents some
yellow points on its summit no disadavantage will ensue, but with a mantle each of
these points produces a deposit of carbon which gradually spreads until it covers
the mantle, stops the draught, and causes the lamp to smoke. It is thus seen that
owing to the interposition of the considerable resistance to the draught produced
by the mantle and to the obstruction caused by the latter after it has become
partially covered with lamp-black, the combustion of petroleum with a blue
flame within a mantle involves conditions different to that of heating.
The arrangements hereinafter described by which the question is solved, form
a novel combination which is the first to enable a practical result to be obtained
with an incandescent petroleum lamp in which a wick is employed.
The invention therefore has for its object a system of incandescent wick-lamp
for the combustion-of hydrocarbons in which the distribution of the air currents
is such that whatever may be the external conditions and the defects of the mantle
placed on the lamp, the blue flame produced will always remain perfectly stable
and never be converted into a yellow smoky flame.
My invention is characterized more particularly by the device for the supply of
external air to the outer and upper faces of the wick in such manner that at
the moment of passage of the slower wave of the exterior vertical ascending current
of air an acceleration is produced by the draught or expansion of a second air
current in a horizontal or inclined direction with regard to the first, in such
manner as to counteract the tendency of the flame to descend to the wick.
My improvement is illustrated by way of example in the accompanying drawings
wherein Figure 1 is a vertical section of a burner provided with two deflectors
having intermediate air inlets whereby a current of air is produced on a level with
the upper edge of the wick. Figure 2 is a similar section shewing the second
deflector as united to the first and without any intermediate introduction of air
in which case it is by expansion that the acceleration of the horizontal movement
of the air is produced. Figure 3 is a modification. Figure 4 represents another
modification in which the second deflector is arranged for the supply to the wick
of a current of air wholly in a horizontal direction. The same letters of reference
denote like parts in all the figures.
My improved lamp burner comprises a tube a in which a wick works in any
sutiable manner and having at its upper part an internal deflector for diverting
from the inner edge of the wick the central current of air entering at orifice cor
through a tube traversing the oil vessel, the air thus circulating in the interior of
tube a being heated and having at the deflector of the tube a low velocity so that
combustion may be maintained upon the inner surface of the wick. A current of
air from the exterior is conducted on to the outer and upper surfaces of the wick
by a double deflector de which air being less heated than that in the interior
causes the extinction of the flame at the said surfaces of the wick. Above the
wick is mounted a disc-shaped head f which is traversed by the air supplied by
the inner tube, the air being supplied through the orifices g to the flame after
having been raised to a very high temperature. The disc head may be made either
solid or hollow and be of any suitable form or arrangement for imparting to the
flame the form most appropriate to that of the mantle. The two deflectors de are
designed to supplement each other by supplying currents differing in temperature,
direction, and velocity. The addition of a second deflector thus permits of obtain-
ing a stable flame under the conditions involved by the use of a mantle.
I reserve the right to vary the number of the deflectors and also their form and
height.
Figure 2 shews a modification in which the second deflector e is united to the
first one d without any circulation of air between them, with this arrangement
compression or dilatation occurs in the external current, and this compression or
this dilatation will be transmitted to the annular space h. When the external

page_text: causes of perturbation cease, the air stored in space h expands and forms a
momentary current which re-establishes the normal equilibrium. The same result
may be obtained by making the internal deflector in the form of a collar d' within
the deflector e (as shewn in Figure 3). The second deflector e may also be arranged
as shewn in Figure 4 for conveying to the external and upper surfaces of the wick
a relatively cool horizontal current of air and which has circulated from its entry
into the lamp up to the wick in a sensibly horizontal plane. This arrangement
may also be confined with that represented in Figures 1, 2, and 3.
The lamp would be furnished with a chimney for producing the draught
necessary for the proper working of the burner and air inlets may, or may not, be
provided between the chimney and its supporting gallery.
It is to be understood that the form and dimensions of the burner may be
varied; the right is also reserved of modifying the accessory arrangements to suit
different applications.
Dated this 15th day of September 1897
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancory Lane, London.
Improvements in incandescent on Lamps.
I, LEOPOLD RALPH ATHENOR MOREL, of 57, Boulevard Pereire, Paris, France,
Engineer, 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:-
This invention relates to incandescent oil lamps and consists essentially in the
means whereby air is admitted or restored to the flame when and in such manner
as may be required to prevent the flame firing back to the wick and maintain
a constant blue flame.
Lamps hitherto constructed for incandescent lighting by the vapourization of
petroleum from a wick, are subject to the two-fold defect of difficulty of ignition
and want of stability of the blue flame in consequence of the two surfaces of the
wick being exposed to currents of air of different velocities and having different
temperatures. The inner surface of the wick receives a current of air of low
velocity which furnishes a sufficient volume of hot air to support combustion while
its outer surface receives a current of air of accelerated velocity which carries
upwards the petroleum vapours disengaged from the outer and upper surfaces of
the wick. The flame is consequently only maintained at the inner surface of the
wick, there being no flame on the upper and outer surfaces at which the evolution
of the petroleum vapour is maintained by the heat afforded by the combustion of
the petroleum at the interior surface of the wick. The mixture of air and vapours
evolved ignites only at a certain distance above the wick and if the proportions of
the mixture be correct the combustion is complete, the flame is blue, and the
heat of combustion is sufficient to maintain à Welsbach mantle perfectly incan-
descent. When the blue flame is stable it may be concluded that the velocity of
propagation of the flame in the combustible mixture is equal to the velocity of
How of said mixture. But this equilibrium which is analogous to that of a ball
poised on a jet of water, may be destroyed by many causes and more especially
by:
1st. Excessive heating of the ascending current which tends to increase the
velocity of downward propagation to a preponderating extent;
2nd. Vibration of the air around the lamp, producing waves or phases of

page_text: alternately accelerated and retarded velocity so that at the moment of retarda-
tion the velocity of propagation of the flame exceeds that of the flow of the mixture
which fires back to the upper edge of the wick.
The presence of the mantle still further diminishes the stability of the flame,
this influence being such that certain arrangements which would otherwise ensure
a stable blue flame almost insensible to external disturbances, do not admit of: a
mantle being used; whilst although the blue flame of a heating lamp may present
some yellow points without inconvenience, it is otherwise when a mantle is used
as each of these points produces a deposit of carbon which gradually spreads until
it covers the mantle, stops the draught, and causes the lamp to smoke. The im-
peding of the draught by the mantle and the still greater obstruction presented
when the mantle has become partially covered with lamp-black, therefore involve
conditions in the combustion of petroleum with a blue flame within a mantle,
different to those which obtain when the flame is merely used for heating purposes.
The arrangements hereinafter described constitute a novel combination whereby
for the first time a practical solution of the problem is obtained in the case of an
incandescent petroleum lamp in which a wick is employed.
The invention therefore consists in a system of incandescent wick-lamp for the
combustion of hydrocarbons, in which the distribution of the air currents is such
that whatever may be the external conditions and the defects of the mantle the
blue flame produced will always remain perfectly stable and never be yellow
and smoky.
My invention is characterized more particularly by the device for conducting
external air to the outer surface and upper edge of the wick in such manner that
at the moment of retardation of the exterior vertical ascending current of air an
acceleration is produced by the draught or expansion of a second air current in a
horizontal direction or inclined relatively to the first, in such manner as to counter-
act the tendency of the flame to descend to the wick.
My invention is illustrated in the drawings accompanying my Provisional Speci-
fication wherein Figure, I is a vertical section of a burner provided with two de-
flectors having intermediate air inlets whereby a current of air is produced on a
level with the upper edge of the wick. Figure 2 is a similar section shewing the
second deflector as united to the first and without any intermediate introduction
of air in which case it is by expansion of the air that the acceleration of the
horizontal movement of the air is produced. Figure 3 is a modification of Figure 2.
Figure 4 represents another modification in which the second deflector is adapted
to conduct to the wick a current of air which is wholly in a horizontal direction.
The same letters of reference denote like parts in all the figures.
My improved lamp burner comprises a wick tube a in which the wick is adjusted
by any suitable means, the inner wall of the tube having at its upper part an
internal deflector b for diverting the central current of air from the inner edge of
the wick, this air entering at orifice c at the bottom of the inner tube if it
traverses the oil vessel becoming heated and passing the deflector b at a low
velocity so that combustion is maintained at the inner surface of the wick. A
current of air from the exterior is conducted on to the outer surface and upper edge
of the wick by a double deflector de; this air being less heated than that of the
central current causes the extinction of the flame at the said outer surface and
edge of the wick. Above the wick is mounted a hollow disc-shaped head f which
is traversed by the central current of air, the air entering at the underside and
being emitted through orifices y in the edge of the disc so as to impinge on the
flame after having been raised to a very high temperature. The disc head may
however be made solid and be of any, suitable form or arrangement for imparting
to the flame the form most appropriate to that of the mantle. The two deflectors d
are designed to supplement each other by supplying currents differing in tempera-
ture, direction, and velocity. The addition of a second deflector thus permits of
obtaining a stable flame under the conditions involved by the use of a mantle but
the number of the deflectors may be varied and also their form and height.
e

page_text: h
Figure 2 shews a modification in which the second deflector e is united to the
first one d so that there is no intermediate circulation of air, the result of this
arrangement being that when any compression or dilatation of the external current
occurs this compression or this dilatation will be transmitted to the annular
space
and when the external cause of perturbation ceases, the air stored in space h expands
and forms a momentary current which re-establishes the normal equilibrium.
The same result may be obtained by making the internal deflector in the form of
a mere collar d within the deflector e (as shewn in Figure 3). The second
deflector e may also be constructed as shewn in Figure 4 so as to convey to the
external and upper surfaces of the wick a relatively cool current of air flowing
from its point of entry to the wick in a sensibly horizontal direction. This arrange-
ment may be combined with that represented in Figures 1, 2, and 3.
A chimney would be provided for producing the draught necessary for the
proper working of the burner, and air inlets may or may not be provided between
the chimney and its supporting gallery.
It is to be understood that the form and dimensions of the burner may be varied
and that the accessory arrangements may be modified as may be required.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:-
:-
An incandescent hydrocarbon lamp burner provided with means whereby air
is admitted or restored to the flame in such manner as to prevent the flame firing
back to the wick, and in particular with means consisting essentially of two or
more deflectors and intermediate annular air spaces (with or without intermediate
admission-of air thereto) so disposed as to direct air currents on to the outer
surface and upper edge of the wick one of the air currents being vertical and the
other sensibly horizontal, substantially as specified.
Dated this 7th day of June 1808
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.