IMPROVEMENTS IN GAS LAMPS to be as follows
Year: 1884

page_text: I FREDERICK SIEMENS of N° 12 Queen Annes. Gate, Westminster, in the
county of Middlesex, Engineer do hereby declare the. nature of my invention
for "IMPROVEMENTS IN GAS LAMPS to be as follows:-
"
My invention relates to the construction of a gas lamp, the flame of which burns
steadily without a glass and is supplied with hot air from above without requiring
any parts underneath the flame that interfere with the downward reflection of the
light thereof.
For these purposes, I place the burner within a concave or conical cap, the lower
surface of which acts as a reflector for the flame, while on the upper surface are
formed firstly passages extending from the lower edge of the cap to the summit
thereof where they communicate through openings with the interior of the cap, so
that air can enter the lower end of such passages, and issue at top in proximity to
the burner. Secondly, I form in the cap other passages into which the gaseous
products of combustion from the burner pass through one or more openings at the
summit of the cap from which point these passages lead down to the lower edge
of the cap and then up again to the summit, where they communicate with a
chimney.
•
Thus the products of combustion are caused to pass first downwards to the
lower edge of the cap and then up again to the summit on their way to the
chimney and in their course they are made to give off their heat to the first named
passages, thereby inducing an upward current of air therein which becomes heated
to a considerable degree both by the transmitted heat of the products of combustion
and by the radiated beat of the flame.
Such heated air in issuing through the openings at the summit into the interior
of the cap, causes the burner contained therein to be surrounded by a stratum of
hot air which nearly fills the cap, and in which the flame burns steadily without a
glass and without requiring to be enclosed below. The said cap with its two sets
of passages can be variously constructed; thus, according to one arrangement the
cap may consist of four concave or conical shields, fitted one over the other with
spaces between them which constitute the before described passages. The inner-
most shield constitutes a reflector, and the space between it and the next one
constitutes the before mentioned hot air passages, while the other three shields
together form the passages for the products of combustion, which first pass down-
ward between the second and third shield, and then upward between the third and

page_text: fourth shield. The third shield' which forms the partition between the two parts
of the passage for the combustion gases is by preference formed of or faced with a
.bad conductor of heat so as to retain this as much as possible in the inner part of
the passage which, is in contact with the air passage. The latter may be formed
with baffles or partitions so as to cause the air to pass in a spiral, zig-zag, or other
tortuous course, and thus to remain as long as possible in contact with the passages
for the combustion gases. The communication between the latter and the space
immediately above the flame is by preference formed by a downwardly projecting
nozzle, round which are formed the openings through which heated air issues into
the cap.
•
A small hole is formed in the cap, by which the flame can communicate directly
with the chimney through which the products of. combustion. escape, so as to
establish an upward draught therein on first lighting the lamp. ..

page_text: I, FREDERICK SIEMENS of N° 12 Queen Annes Gate, Westminster in the
county of Middlesex, Engineer, do hereby declare the nature of my invention
for "IMPROVEMENTS IN GAS LAMPS" 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 the construction of a gas lamp the flame of which burns
steadily without being enclosed by a glass and is supplied from above with air
heated by the products of combustion, there being no parts under the flame to
interfere with the downward passage of the light.
Figs. 1 and 2 of the accompanying drawings are vertical sections, fig. 2 being
taken on the line X X of fig. 1 and figs 3 and 4 are plans, fig 4 being taken as
from below, also fig 5 is a sectional plan on Y Y of fig. 1, shewing one form of
lamp according to my invention suitable for a light in such a position that a shadow
on one side is not objectionable. In this lamp, two flat flame burners are placed
side by side within a bell reflector R. The products of combustion pass through a
mouth r which should be so limited in area and suited to the form of the flames as
to give passage for little or no air besides ;-the products descend a channel a and
ascend a¹ to the chimney c. Air entering by lateral orifices ascends channels b on
each side of a becoming heated on its way, and issues into the upper part of the
reflector to supply the flames. Through the crown of a there is a small aperture a*
for passage of a portion of the bot products of combustion to start the chimney
draught. A valve may be provided to close this aperture when the draught is
established. The closing of this valve may be made automatic by attaching it to a
compound strip of metal that when heated will become bent or unbent, or to a
metal rod that will expand when heated. Fig. 6 is a vertical section and fig. 7
a plan looking from below shewing a lamp with channels operating as above
described but arranged in circular form surrounding the light, the inner wall of
the air channel b constituting a reflector. The partition separating the channels a
and a is preferably covered with a layer of imperfectly conducting material such
as ashes sheet, so as to retain in the channel a a greater amount of heat available
for heating the air ascending the channel b. The partition separating a from b
instead of being plain may be corrugated or provided with projections or ribs, so as
to increase its heat absorbing conducting and radiating power; and in like manner
corrugations, projections or ribs may be used in the channels of the lamp shewn in
figs 1 to 5 inclusive. In both lamps, single burners may be used, or double burners
as shewn, or multiple burners, care being taken to suit the size and form of the
mouth r to the flames so that practically only products of combustion shall pass
through it, without taking with them any material part of the air supplied from
the channels b. When two or more burners are used, they may be placed.at an
angle one to the other instead of parallel, as shewn in the drawings.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that
what I claim is
.
"
The construction of gas lamp with burners not enclosed having their flames
supplied from above with air heated by ascending channels arranged side by side
with channels along which the hot products of the flames descend, substantially as
herein described and illustrated by the drawings.