Year: 1897

page_text: I, WALTER FREDERICK SHARP, of 51, Granby Street, Leicester, Lamp Manufac-
turer, do hereby declare the nature of this invention to be as follows:-
This invention has reference to gas lamps and is designed with the object of effect-
ing certain improvements in the construction thereof which are of especial value in
connection with the incandescent system of gas lighting, as applicable to shop
fronts and public places.
The principal desideratum in connection with incandescent gas lamps is that
the light shall burn in a comparatively quiet chamber or atmosphere, free from
draughts which besides flickering the light, are destructive to the mantle.
This desideratum is generally obtained by enclosing the incandescent burners
in a large globular or other shaped glass or opal globe or chamber with a metal
hood or head at the top for the escape of the hot air.
It is found in general practice that these large and expensive globes become
intensely hot and frequently crack as the result of sudden contraction caused by
rain falling thereon, or by low temperature, as in frosty weather, when the lights
are extinguished.
Now the object of the present invention is to remedy this disadvantage and to
so construct the head or hood of the lamp as to ensure a rapid passing off of the
hot air and combustion products and to keep the wall of the glass globe compara-
tively cool.
For this purpose I arrange inside the globe or chamber a domne or hood under
which the burners are located or directed so that the combustion. products and
heated air pass therein and thence into a central chamber in the head of the lamp and
finally into the upper part of the head of the lamp which has therein openings
communicating with the atmosphere.
The base of the head where it rests on the globe is corrugated or otherwise
constructed so that a space or spaces is left between it and the head through which
the cool air or atmosphere can pass into the annular space or chamber in the
head of the lamp formed between the central hot air or exit pipe and the outer
wall of the lamp.
The outer wall of the lamp head may also be perforated to permit the cool
outer air to enter and descend between the globe and the dome and escape up
through the latter.
By the above construction the heated air and combustion products cannot become
diffused within the globe but rise to the upper part of the globe and are conducted
away by the dome, direct into the head of the lamp where they escape.
Moreover the space in the upper part of the globe between the latter and the
dome is maintained at a comparatively cool temperature by the down passing
current of cool air from the cool chamber herein before mentioned.

page_text: By this means the globe of the lamp cannot get overheated and the liability to
crack from this cause is therefore avoided.
The invention is applicable to other than incandescent lamps.
Dated this 18th date of October 1907
انا
BOULT & WADE,
Agents for the Applicant.
improvements in Gas Lamps, mainly applicable for Outside Use.
I, WALTER FREDERICK SHARP, of 51, Granby Street, Leicester, Lamp Manufac-
turer, 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:-
1
This invention has reference to gas lamps and is designed with the object of effect-
ing certain improvements in the construction thereof which are of especial value in
connection with the incandescent system of gas lighting, as applicable to shop
fronts and public places.
The invention will be understood by reference to the accompanying drawing
showing a vertical section of an incandescent lamp of well known construction
having my improvements incorporated therewith.
The principal desideratum in connection with incandescent gas lamps is that
the light shall burn in a comparatively quiet chamber or atmosphere, free from
draughts which, besides flickering the light, are destructive to the mantle.
This desideratum. is generally obtained by enclosing the incandescent burners
in a large globular or other shaped glass or opal globe or chamber with a metal
hood or head at the top for the escape of the hot air.
It is found in general practice that these large and expensive globes become
intensely hot and frequently crack as the result of sudden contraction caused by
ain falling thereon, or by low temperature, as in frosty weather, when the lights
are extinguished.
Now the object of the present invention is to remedy this disadvantage and to
s construct the head or hood of the lamp as to ensure a rapid passing off of the
hot air and combustion products and to keep the wall of the glass globe compara-
tively cool.
For this purpose I arrange inside the glass globe A. a dome or hood B under which
the burners C and chimneys Cover the latter are directed so that the combustion
products and heated air pass upwards into the head D of the lamp which has
openings D D therein communicating with the atmosphere.
The hood B is located in the upper part of the globe and is fixed in position by
screwed rods E each of which passing through a hole B¹ in the dome and through
a lug B2 on the cylindrical part thereof.
The metal head of the lamp is formed as usual in two separate parts D D³ the
lower part D³ forming the base of the head is held on to the globe by the usual
screwed rods E, the bottom ends of which take under two hooks F¹ soldered to the
cylindrical metal foot F of the lamp which is also perforated to admit air.
When the screwed rods E which also pass through lugs D extending from
the side of the metal base D³, are tightened by means of the nuts E the globe is
clamped between the parts F and D³.
The metal base D³ is provided with tabs D which are turned down under the
inner edge of the globe and also with lugs De to each of which is pivotted a.catch
lever G arranged to enter the bifurcation in a projection H on the head of the

page_text: lamp and become locked thereagainst as shown. A cottar is then passed through
the hole H and presses frictionally against the catch lever so as to prevent the
latter working loose.
An annular space B³ is formed between the globe and the dome and the head
is perforated at D7 so that a supply of cool fresh air enters thereat and passing
downwards into the annular space keeps the upper part of the lamp cool while
the heated air is prevented congregating there on account of the presence of the
dome through which it passes and escapes as before mentioned.
An equably cool temperature in the upper part of the globe is also further
assisted by corrugating the metal rim or base 13 of the head which rests thereon
by which means cool air can pass through the spaces D³ formed under the corruga-
tions and into the annular chamber B³.
A loose metal cylinder J is inserted over the upper part of the dome B and is
furnished with vertical slots J¹ therein to pass over the arms K which are rivetted
to the side of the head and are provided with a central boss J2 through which the
gas supply pipe L passes.
By the above construction the heated air and combustion products pass upwards
through the dome B and cylinder J into the head of the lamp and escape through
the openings DD2 therein while the cool air enters the perforations D7 passing
downwards into the annular chamber B3. Cool air also passes through the
spaces D under the corrugated base D³ and enters directly into the said annular
space thereby preventing the upper part of the lamp globe getting overheated.
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:
1. An incandescent gas lamp of the character specified provided with a dome
suspended over the burners and forming a annular space between it and the
upper part of the globe substantially as and for the purpose described.
2. In an incandescent gas lamp of the character specified the combination of a
dome such as B an annular space B³ between the latter and the globe and air
passages 1 communicating therewith and with the atmosphere substantially as
and for the purpose described.
3. The improved construction of incandescent lamp of the character specified
substantially as described and illustrated in the accompanying drawing.
Dated this 18th day of July 1898.
BOULT & WADE,
Agents for the Applicant.