Improvements in Chimneys for Incandescent Gas Lamps.
Year: 1895

page_text: Date of Application, 13th Mar., 1895-Accepted, 27th Apr., 1895
COMPLETE SPECIFICATION.
Improvements in Chimneys for Incandescent Gas Lamps.
I, ERNST FRANZ WILHELM HIRSCH of Radeberg, Saxony, German Empire,
Glass Works Proprietor, 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 :-
In all gas lamps having destructible incandescing materials or bodies such for
instance as mantles, it is of great advantage either to avoid the removal of the
chimney for the purpose of cleaning (except when the mantle has to be renewed)
or to be able to remove it in such a manner that the mantle is not liable to be
injured.
As it is difficult when the chimney is held in the gallery or holder, to remove it
therefrom without shaking the incandescing body (hereinafter called the mantle)
it is preferable not to remove the chimney for cleaning rather than to risk the
destruction of the expensive mantle by such removal.
The object of the present invention is to so construct the chimney that its
removal from the gallery or holder except when the mantle has to be renewed is
unnecessary; or that the removal of the chimney can take place without shaking
the mantle.
This object is mainly attained by dividing the chimney horizontally into two or
more parts, the lowest part being placed in the gallery or holder and supported
thereby, while the other part or parts is or are fitted upon or in the next lowest
part, the bottom part serving as a guide.
The placing of the upper part or parts in or over the lowest part thus becomes
easy and convenient.
The superposed part may serve the purpose of protecting the part placed in the
gallery or holder against the direct influence of the flame, and this is of special
value when the gas lamp is provided with a shade, the part surrounding the flame
being visible to the eye; or the superposed part may form only a continuation of
the part placed in the gallery or holder, and therefore in case of shades of bell-,
globe-, tulip- or similar shape being used reach up beyond the same.
In both cases the removable part may rest on the fixed part; but in the first
case the removable part may rest on the gallery or chimney holder itself.
In all cases the parts of the chimney may be plain or decorated, colored or
white, and the removable part may be so shaped as to serve for regulating the
draft.
The accompanying drawings show various examples of the way in which the
invention may be carried into effect. In all the figures a is the gallery or chimney
holder of the lamp, the part of the chimney placed in the gallery, and ca
further part placed in or over the fixed chimney part b, which latter always serves
as a guide.
Figures I, II and III show the inserted parts c arranged to shield the part b
against the direct influence of the flame, thus obviating the necessity for cleaning
the last named part b.
The part c may be supported in many ways; for instance as in Figures I, III, V
and VI by a shoulder à resting upon the part b; or as in Figure II by resting on
a widened portion or shoulder of the part b; or as in Figure 1V by a rib or
flange d resting on part b; or as in Figure IX by the burner itself; or in any other
suitable manner

page_text: In the construction shown in Figures I, II and III the part is quite out of
contact with the flame and hence cannot become dirtied by it; cleaning of the
part therefore becomes necessary probably only when the mantle has to be
changed; while the part c wherein the flame burns and which therefore has to be
cleaned more often, is easily removable; there is no fear of injuring the mantle
because the part 6 forms a guide for the upper part c.
The part c may be so arranged as to rest above and below upon and in the
part b. The part e may also at its lower end be provided with a thin metallic rim
with upwardly projecting strips, see Figure X, so that it may easily enter the
part b, while the part e as it is being inserted finds a safe guide in the part b, and
when inserted is held securely, which is of advantage in portable lamps. Any
holding strips or like devices may be arranged in the part 6 itself, see Figure XI,
for the entry or holding or both of the part c.
For certain purposes the part 6 need not be shielded or need only be partly
shielded from the direct influence of the flame; in this case (see Figures V and VI)
the part c does not enter far into the part b, or as shown in Figures VII and VIII
the part c is outside the part b, and is either below or not the highest point of the
mantle e.
With this second construction, the upper part of the chimney can also be
removed for cleaning without danger to the mantle, and be as easily put on again
and even in this case the lower part b will not be much dirtied by the flame
because as the part c is not pushed in as far as the bottom or below the bottom of
the mantle the effort of the draft will always be towards the upper part or parts
of the chimney.
The extent to which the part b is to be shielded against the influence of the
flame by the insertion of the part c is optional; the inserted part may be made
shorter or longer, or the shoulder on the part b, Figure II, may be higher or
lower, or the arrangement on the burner for carrying the part e may be varied to
suit; or other suitable ways may be adopted.
In all these arrangements the part c may be variously shaped; it may for instance
be other than plainly parallel, in order to facilitate the draught of the flame or to
gain some other advantage.
The shape of the part b may also be varied and ornamented or otherwise formed
advantageously to suit the light and the eye.
Further the chimney may consist of more than two parts, such for instance as
shown in Figures XII and XIII.
From the examples given it will be understood that the modes of carrying the
invention into effect may be greatly varied, but that the main feature in all cases
is that a part of the length of the chimney can for the purpose stated be easily
and conveniently for a desired part of its length put in or over the part which is
held in the gallery or holder, and be removed therefrom, the unmoved part always
serving as a guide for the removable part.
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. A chimney for an incandescent gas lamp divided horizontally into two or
more parts and having the part which is held in the gallery or chimney holder
partly or wholly protected by one or more other parts c against the influence of
the flame, the said part or parts c being capable of easy removal and replacement
for the purpose of cleaning or renewal, so that shaking of the mantle or incandescing
material is avoided, substantially as herein before described and shown in Figures I
to VI and Figures XII aud XIII.
2. A chimney for an incandescent gas lamp divided horizontally into two or
more parts, of such a shape that an upper part c may be pushed more or less over
the lower part 6 held in the chimney holder or gallery the taking off or replacement
of which part e for cleaning or renewal being effected without shaking the mantle

page_text: or incandescing material, substantially as hereinbefore described and shown in
Figures VII and VIII.
3. A chimney for an incandescent gas lamp of such a shape that a cylinder or
part c is pushed into the part 6 held in the gallery or chimney holder, the said
cylinder c resting on the burner and protecting the outer part 6 wholly or partly
against the flame and being easily placed in the part 6 or removed therefrom
without shaking the mantle or incandescing material, substantially as hereinbefore
described and shown in Figure IX.
Dated this 12th day of March 1895.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.