IMPROVEMENTS IN LAMPS
Year: 1880

page_text: LETTERS PATENT to Frederick Siemens, of Dresden, in the German Empire,
but at present of No. 12, Queen Anne's Gate, Westminster, in the County of
Middlesex, for an Invention of "IMPROVEMENTS IN LAMPS."
PROVISIONAL SPECIFICATION left by the said Frederick Siemens at the Office
of the Commissioners of Patents on the 16th April 1880.
'
FREDERICK SIEMENS of Dresden in the German Empire but at present of
No. 12 Queen Anne's Gate Westminster in the County of Middlesex. "IMPROVE-
MENTS IN..
.LAMPS."
In the Specification to Letters Patent dated 5th June 1879 No. 2231, I
described certain constructions of lamps wherein the heat of the products of com-
bustion from the flame was imparted to the air supply or to the combustible gas,
or to both, for increasing the illuminating power of the flame, by causing such
products of combustion and the air or gas to pass in opposite directions through
adjacent passages filled with wire gauze or other materials offering extended
surfaces for giving off and taking up heat. According to one part of my present
Invention I construct such lamps as follows. An annular burner, consisting by
preference of a number of small vertical tubes rising from an annular chamber into
which the combustible gas passes, has its central space formed into a regenerative
chamber containing materials offering extended surfaces for taking up heat, which
chamber communicates at bottom with a passage or pipe leading to a chimney, and
is extended upwards at top to a certain height beyond the level of the burner,
such extension being by preference of reduced diameter. This inner chamber
serves for the downward passage of the products of combustion, which pass into it
from the top of the flame at its upper end and are drawn downwards through it
by the draught of the chimney into which the products escape after imparting the
greater part of their heat to the sides of the chamber and the materials contained
therein. Surrounding the outside of the burner is a second chamber open at its
upper and lower ends, also containing material offering extended surfaces, which
material becomes heated by conduction and radiation from the heat given off to the
central chamber and imparts such heat to the air passing upwards through the
chamber on its way to the flame of the burner, at the level of which the chamber
terminates, and at which point it is by preference made of reduced diameter. At
ל
877

page_text: the upper edge of such outer chamber, as also surrounding the extension of the
inner chamber at a certain distance above the top of the burner, I prefer to provide
annular notched or comb-like shields such as were described in the Specification
to my Patent No. 3555 of 1879, and which serve to divide the heated air supply
into a number of separate jets that are made to impinge upon the outer and inner
surfaces of the flame, thereby increasing its vividness and steadiness. As the flame
of the burner is drawn inwards directly over the top of the inner chamber it is
necessary to carry this up to such a height as to afford the desired length of flame;
for this purpose, according to another part of my Invention, I fit on to the upper
end of such chamber, which terminates at a moderato height above the burner, a
separate cylinder by preference of fire-clay or other suitable refractory material,
that will readily withstand the high heat of the flame at that point, and that can
be renewed when it becomes deteriorated.
According to another part of my Invention I construct the filling of the regene-
rative chambers of lamps of the kind above referred to, of a number of perforated
hollow cones or frustrum of cones of metal or fire-clay, placed one above the other,
so that the currents of the products of combustion or the air in passing through
the perforations of each cone in succession, are effectually broken up, and each
particle thereof brought into intimate contact with heat absorbing or heat imparting
surfaces.
According to one arrangement for producing the requisite downward draught in
the central chamber of the above described lamp, I connect the lower end thereof
to a pipe or pipes that is or are led up to and open into a tube situated imme-
diately above the chimney of the lamp. By this arrangement, when the lamp is
first lighted, the whole of the products of combustion will pass up through the
chimney and tube above, by which means a draught will be induced in the said
pipe or pipes leading from the bottom of the central chamber and after a short
interval of time this draught will be sufficiently powerful to draw the whole or a
great proportion of the products of combustion downwards through the chamber.
According to another arrangement suitable more particularly where a number of
burners are arranged round a central stem, the arms supporting the burners
constitute the pipes for leading off the products of combustion from the lower ends
of the central regenerative chambers to a tube forming part of the central stem
and constituting a chimney of sufficient height for maintaining the requisite
draught this being in the first instance produced by the ignition of a gas jet
inside the chimney. This gas jet may be afterwards extinguished, and the draught
be continuously kept up by not quite extinguishing the flames of the burners when
not in use.
Lamps of the above described construction may be adapted to burn effectually
and with a steady flame without the aid of a chimney glass to the burner. For
this purpose the outer regenerative chamber is made of increased vertical length,
so as, by the increased column of heated air passing up through it, to obtain
sufficient intensity of the air current for effecting perfect combustion and steadiness
of flame. In this case the upper end of the outer chamber may be closed outside
the burner, the whole of the air being made to pass into an annular space inside
the burner whence it is deflected in divided jets on to the flame by the before
mentioned annular notched shield or doflector. When lamps constructed as above
described are used in the open air the flame may be protected against the wind by
a suitable lantern by preference of bell shape having a wide opening at bottom.

page_text: in pursuance of the contin of the Letters ratent nied by
the said Frederick Siemens in the Great Seal Patent Office on the 15th
October 1880.
FREDERICK SIEMENS of Dresden in the German Empire but at present of
No. 12 Queen Anne's Gate Westminster in the County of Middlesex.
MENTS IN LAMPS."
"
IMPROVE-
In the Specification to Letters Patent dated 5th June 1879 No. 2231, I described
certain constructions of lamps wherein the heat of the products of combustion from
the flame was imparted to the air supply or to the combustible gas, or both, for
increasing the illuminating power of the flame, by causing such products of combus-
tion and the air or gas to pass in opposite directions through adjacent passages filled
with wire gauze or other materials offering extended surfaces for giving off and
taking up heat. According to one part of my present Invention I construct such
lamps as follows. An annular burner consisting by preference of a number of
small vertical tubes rising from an annular chamber into which the combustible gas
passes has its central space formed into a regenerative chamber containing materials
offering extended surfaces for taking up heat, which chamber communicates at
bottom with a passage or pipe leading to a chimney and is extended upwards at
top to a certain height beyond the level of the burner, such extension being by
preference of reduced diameter. This inner chamber serves for the downward
passage of the products of combustion which pass into it from the top of the flame
at its upper end and are drawn downwards through it by the draught of the
chimney into which the products escape after imparting the greater part of their
heat to the sides of the chamber and the materials contained therein. Surrounding
the outside of the burner is a second chamber open at its upper and lower ends,
also containing material offering extended surfaces, which material becomes heated
by conduction and radiation from the heat given off to the central chamber and
imparts such heat to the air passing upwards through the chamber on its way to
the flame of the burner, at or about the level of which the chamber terminates, and
at which point it is by preference made of reduced diameter. At the upper edge of
such outer chamber, as also surrounding the extension of the inner chamber at a
certain distance above the top of the burner, I prefer to provide annular notched or
comb-like shields such as were described in the Specification to my Patent
No. 3555 of 1879, and which serve to divide the heated air supply into a number
of separate jets that are made to impinge upon the outer and inner surfaces of the
flame, thereby increasing its vividness and steadiness. As the flame of the burner
is drawn inwards directly over the top of the inner chamber it is necessary to carry
this up to such a height as to afford the desired length of flame; for this purpose,
according to another part of my Invention, I fit on to the upper end of such
chamber, which terminates at a moderate height above the burner, a separate
cylinder by preference of fireclay or other suitable refractory material, that will
readily withstand the high heat of the flame at that point, and that can be renewed
when it becomes deteriorated.
According to another part of my Invention I construct the filling of the regene-
rative chambers of lamps of the kind above referred to, of a number of perforated -
hollow cones or frustrums of cones of metal or fireclay, placed one above the other,
so that the currents of the products of combustion or the air in passing through
the perforations of each cone in succession are effectually broken up and ench
particle thereof brought into intimate contact with heat absorbing or heat imparting
surfaces.
According to one arrangement for producing the requisite downward draught in
the central chamber of the above described lamp, I connect the lower end theṛeof to a

page_text: pipe or pipes that is or are led up to and open into a tube situated immediately
above the chimney of the lamp. By this arrangement, when the lamp is first lighted,
the whole of the products of combustion will pass up through the chimney and
impart beat to the tube above, by which means a draught will be induced in the
said pipe or pipes leading from the bottom of the central chamber and after a short
interval of time this draught will be sufficiently powerful to draw the whole or a
great proportion of the products of combustion downwards through the chamber.
According to another arrangement suitable more particularly where a number of
burners are arranged round a central stem, the arms supporting the burners consti-
tute the pipes for leading off the products of combustion from the lower ends of the
central regenerative chambers to a tube forming part of the central stem and con-
stituting a chimney of sufficient height for maintaining the requisite draught, this
being in the first instance produced by the ignition of a gas jet inside the chimney.
This gas jet may be afterwards extinguished, and the draught be continuously kept
up by not quite extinguishing the flames 'of the burners when not in use.
Lamps of tlie above describod construction may be adapted to burn effectually
and with a steady flame without the aid of a chimney glass to the burner. For
this purpose the outer regenerative chamber is made of increased vertical length, so
as, by the increased column of heated air passing up through it, to obtain sufficient
intensity of the air current for effecting perfect combustion and steadiness of flame.
In this case the upper end of the outer chamber may be closed outside the burner,
the whole of the air being made to pass into an annular space inside the burner
whence it is deflected in divided jets on to the flame by the before mentioned
annular notched shield or deflector. When lamps constructed as above described
are used in the open air the flame may be protected against the wind by a suitable
lantern by preference of bell shape having a wide opening at bottom.
Figs. 1 to 5 of the accompanying Drawings shew one arrangement of my before
described improved lamp. Fig. 1 shews an elevation, Fig. 2, an enlarged vertical
section on line W W Fig. 3, Fig. 3 a vertical section on line X X Fig. 2, Fig. 4
a section on line Y Y Y Fig. 3, and Fig. 5 shews a section on line Z Z Fig 2.
a a is a cylindrical chamber into which illuminating gas is conducted through a
pipe a¹ which may either project from a wall or bracket or form part of a gas
pendant. In the top of the chamber is fixed a ring of small tubes cc through
which the gas issues in a number of small jets, thus forming an annular burner.
Within the chamber a is formed a second chamber i, having a lateral opening
communicating with the flue tube , and an upper opening concentrically within
the burner c and communicating with the lower end of the regenerative chamber b.
This chamber contains one or more perforated metallic cones d and has its upper
end contracted somewhat, as shewn, and extended a certain height above the tops
of the burner tubes c. Upon such upper portion is fixed the notched shield or
deflector g and above this is fitted a separate cylinder k by preference of fireclay
but which may also be of other suitable heat resisting material. Surrounding the
outside of the gas chamber a is a casing e extending up to nearly the tops of the
burner tubes c, an annular space intervening between the two into which are
introduced one or more perforated conical frustra f and which constitutes the
regenerative chamber for heating the air supply that enters the casing at the open
lower end. The upper end of the casing e is turned over and notched as shewn
at h so as to form an outer notched air deflector. The flue tube ¹ may lead to
any convenient flue or passage for producing the requisite draught, but by
preference it is connected, as shewn at Fig. 1 to a tube immediately above the
lamp, the action of which will be presently explained. The upper part of the
casing 6 is surrounded by a gallery o carrying a lamp glass n, a metal continuation
n' of which opens into the closed lower end of the tube i, a slide or throttle valve
being provided at n² whereby this communication may be more or less restricted.
The action of the lamp is as follows:-Illuminating gas being admitted into the
chamber a, and the jets o being ignited, the lamp will first burn in the ordinary
manner, that is to say, the air for supporting combustion will pass up through the

page_text: regenerator ƒ and being parily caused to flow to the inner side of the ring of
tubes will enter into combustion with the gas, and the resulting flame will be drawn
upward by the draught created by the chimney glass. After this bas continued a
short time (a few seconds being sufficient) the tube will have become heated and will
also have heated the tube ¹ by conduction to such an extent as to induce a certaio
current in an upward direction in the latter, and in consequence of the suction thus
produced at the upper end of the cylinder k, n portion of the heated products of
combustion will be caused to pass downward from the flame through the
regenerative chamber b and chamber into the flue-tube ¹ whence they will
pass into the tube 22. On now more or less closing the communication between
the chimney glass o and the tube nearly the whole of the products of com-
bustion will be caused to pass downwards in the direction above indicated, and
will thus impart their heat to the sides and filling of the regenerative chamber b.
This heat will be imparted partly by radiation and partly by conduction to the
regenerative chamber e and gas tubes c and consequently also to the air and gas
passing up through them, thus producing a greatly intensified light by their com-
bustion, which is still further increased by the action of the notched air deflectors
in dividing up the air supply into a number of small currents impinging on each
side of the flame as described in my previous Patent No. 3555 of 1879. By continuing
the air casing e some distance downwards as shewn and making it of heat
conducting material, a column of heated air of sufficient height will be produced
therein to cause an air current of sufficient intensity for effecting perfect combustion
without the aid of the chimney draught, so that in certain cases the lamp glass
may be dispensed with. A small annular space is left between the cylinder o,
forming the gallery and the casing e through which a small air current passes,
serving to protect the glass n from becoming overheated. As the flame of the lamp
is drawn downward over the edge of the cylinder k by the down draught, it will
be seen that the length of this cylinder will determine the height of the flame. It
is of the greatest importance that lamps burning on the regenerative principle
should have the current of heated products of combustion passing in a downward
direction centrally through the burner, while the air supply is made to pass in
an upward direction, surrounding the current of the products, according to my
present Invention, firstly because by this arrangement the transmission of heat
from the products to the air will be more perfect than with any other arrange-
inent, and secondly because by this means the before described draught of heated
air to the burner, independently of a chimney draught, is obtained. The peculiar
form of the regenerator filling, namely, perforated cones or conical rings of metal
or other heat resisting material, is also of great advantage in offering extended
surfaces for taking up and giving off heat in chambers that are comparatively
of small height and width and as compared with horizontal plates these cones
not only afford greatly increased surface but also the possibility of providing a
much greater number of perforations, which is of great advantage for the perfect
action of the regenerators. In small apparatus however, the filling in for the
regenerators may be dispensed with, as the surfaces of the chambers b and e will of
themselves be sufficient for effecting the requisite interchange of heat. In this case
it is of advantage to make the sides of the chamber 6 of corrugated or ribbed metal.
The lamp may either be suspended by the gas supply pipe a², or by the flue tubes
or 2, or they may be supported on a stand or in any other convenient manner
and two or more may be combined as a candelabra. The tube may either be
nerely continued up a sufficient height to create the requisite draught, or it may
be connected to a flue or passage for leading off the products of combustion, or the
flue tube i' may be connected directly to a chimney flue, the tube i¹ being dispensed
with.
Fig. 6 shews a vertical section and Fig. 7 a sectional plan on line V V of a
modified construction of the before described lamp. The same parts are indicated
by the same letters of reference. In this case the annular gas chamber a has
connected to its central opening a double flue tube i¹ communicating with the

page_text: regenerator b for the products of combustion, which branches to either side of the
lamp and is connected at top to the fluo tube . The construction and action of the
lamp is otherwise the same as previously described. When two or more such lamps
are used in combination as a candelabra they may be arranged as shewn in elevation
at Fig. 8 where the products of combustion are caused to pass through the hollow
arms ii to the central stem p the extension p¹ of which forms the chimney flue for
creating the requisite draught. For producing such draught in the first instance a
gas jet is provided in 2, which may be afterwards extinguished, and the draught
may be maintained while the lamps are not in use by keeping them burning with
a small flame during that time.
Lamps of the above described construction may be adapted to burn effectually
and with a steady flame in the open air without the aid of a chimney glass to the
burner. For this purpose the outer regenerative chamber is made of increased
vertical length, so as by the increased column of heated air passing up through it
to obtain sufficient intensity of the air current for effecting perfect combustion and
steadiness of flame.
Figs. 9, 10 and 11 shew respectively a vertical section a plan and sectional plan
on line U U of a construction of lamp in which the regenerative chamber e for
heating the air is made of some height and constitutes a pedestal for the lamp, and
may either be filled with conical perforated rings as before described or with wiro
gauze or other suitable material is indicated. The upper end of the chamber may
either be entirely open, as in the previous arrangement and provided both with an
inner and an outer notched shield, or the space outside the burner may be closed
at a and the whole of the heated air bo caused to pass between the burner tubes to
the inner space y whence it is caused by the notched shield g to impinge in divided
jets upon the flame. The filling of the inner regenerative chamber b is in this caso
formed of perforated cones of fireclay d formed in one with cylindrical pieces d'
that are separate from each other, so that they can be separately removed and
renewed when defective. The lower end of the chamber b cominunicates with an
underground flue q leading to a chimney flue for producing the necessary draught.
This lamp would burn with a perfectly steady flame without a glass in a quiescent
atmosphere, but when employed in the open air it should be protected from the
wind or draught by a lantern, and by preference I employ for this purpose a bell
shaped glass with large opening at bottomn, as shown. The lamp glass shewn at
Fig. 6 is by preference made of the inverted bell shape shewn, and of opal glass, an
inverted conical mirror & being fitted on to the upper edge thereof in order to reflect
laterally and downwards that portion of the light which otherwise is projected
upwards and is thus more or less entirely lost.
Having thus described the nature of my Invention and in what manner the
same is to be performed I claim :-
First. The construction of regenerative lamps wherein the products of combustion
are caused to pass downwards from the flame through a contral regenerative
chamber within the annular burner of the lamp, while the air required for
combustion passes upwards through an annular regenerative chamber surrounding
the burner of the lamp, substantially as herein described.
Second. The use in lamps constructed as set forth in the preceding claim, of a
separate cylindrical extension of fireclay or other heat resisting material to the
upper end of the central regenerative chamber, by means of which the requisite
height of the flame is obtained, substantially as herein described.
Third. The use, for the filling of the regenerative chambers of lamps, of superposed
hollow perforated cones or conical rings of metal, fireclay or other heat resisting
material, through the perforations of which the air or gases are made to pass in
order to take up heat therefrom or impart heat thereto, substantially as herein
described.
Fourth. In regenerative lamps wherein the products of combustion are caused to
pass downwards through a central regenerative chamber, producing the requisite
down draught in the said chamber by connecting its lower end to a tube or tubes

page_text: that is or are led up to chimney flue above the lamp, the heat from which produces
the requisite draught in the said flue, substantially as herein described with
reference to Figs. 1 to 6 of the accompanying Drawings.
Fifth. In regenerative lamps wherein the products of combustion are caused to
pass downwards through a central regenerative chamber, connecting the lower ends
of the central chambers of two or more such lamps by tubes to a central flue pipe
forming part of the stem by which the lamps are supported, such flue pipe being
provided with a gas jet for producing the requisite draught, substantially as berein
described with reference to Fig. 8 of the accompanying Drawings.
Sixth. In regenerative lamps, the combination of the burner tubes c with the
regenerative chambers a, e, provided with filling d, f, of perforated cones or conical
rings, the notched shields or deflectors g, h, and the separate tubular extension k
arranged and operating as herein described with reference to Figs. 1 to 6 of the
Drawings.
Seventh. The construction of regenerative lamp herein described with reference
to Figs. 9 to 11 of the Drawings, adapted for burning with an open flame.
In witness whereof I the said Frederick Siemens bave hereunto set my
hand and seal this Thirteenth day of October in the year of our Lord One
thousand eight hundred and eighty.