An Improved Automatic Lighting Device for Gas Burners.
Year: 1897

page_text: Date of Application, 31st Dec., 1897-Accepted, 19th Feb.,
1898
COMPLETE SPECIFICATION.
An Improved Automatic Lighting Device for Gas Burners.
1, HUGO BORCHARDT, of 62, Königgratzer Strasse, Berlin, in the Empire of
Germany, 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; reference being had to the accompanying
drawings and to the figures and letters marked thereon that is to say :-
There have already been devised appliances for the automatic lighting of gas
in which a platinum sponge was arranged at a pre-determined height above the
burner-orifice whence thin and sometimes curled or coiled platinum wires were
stretched down to a point in the vicinity of the said orifice.
The action of these automatic lighting devices was based upon the fact that the
platinum sponge in consequence of its contact with the illuminating gas-which
as it issued became mixed with air-was heated to incandescence, and that the
platinum wires attached to the sponge by reason of the well known physical pro-
perties of platinum transmitted the heat to the burner orifice.
The rapidity and reliableness of ignition in those arrangements has however been
mainly dependent upon a condition which was not sufficiently taken into account,
namely upon the method of arrangement of the platinum wires.
Now the applicant has ascertained that the following two conditions have to be
fulfilled in order to ensure the prompt and reliable operation of the platinum wires
referred to:-
"
First; the wires must not extend down to the burner in the form of one single
strand as heretofore, whether spreading or expanding or not in the downward
direction: what they should do on the contrary is to constitute a system expand-
ing or spreading upwardly in the shape of a fan their divergence as nearly as
practicable corresponding to the cone of dispersion of the issuing gas; and
Secondly; the wires should not as in the method heretofore adopted; form a
'frizzled curl" which is very apt to undergo alterations in its position either
under the action of a draught of air or under other influences; but they should
be stretched or strained taut, with adjustable tension, so that they may permanently
retain the position imparted to them.
In the accompanying drawings Figures 1, 2, and 3 are, respectively, a side eleva-
tion, a rear-view and a front view of one form of automatic gas lighting device
combining the novel features above described.
a designates the platinum sponge which is retained between resilient clamps d
mounted in an extension or projection of the burner. Between the said clamps
there is interposed a carrier c automatically retained in place by friction and
adjustable in height, and to this carrier is secured the system of platinum wires b
expanding upwardly in fan shape and stretched or strained over the sponge a.
e designates the burner orifice.
The arrangement above described affords the following advantages: -
Inasmuch as the platinum wires 6 which are arranged at approximately equal
distances apart expand or spread in front of the whole effective surface of the
platinum sponge a, all the heat evolved from the sponge is utilised. in heating the

page_text: platinum wires and the incandescent heat is transferred to the burner orifice by the
shortest way and this action is all the more reliable as all the platinum wires are
situated within the gas cone.
Again, owing to the attachment of the platinum wires 6 to the carrier c, the height
or level of which may be adjusted by simple displacement, the possibility is afforded
of imparting greater or less tension to the wires, as may be required, in securing
them in place.
In some cases indeed the platinum sponges may be provided with small notches or
dents for the wires to be embedded in so that they are effectually precluded from
shifting.
As the platinum sponge a is retained between the clamps d by friction merely it
may if desired be adjusted or displaced by shifting it so that its front surface
is moved more or less into the gas cone since the wires b, being very thin, will follow
the outline or position of the sponge in any situation.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. An automatic lighting device wherein a system of platinum wires expanding
or spreading in fan-shape from the burner-orifice towards the platinum sponge is
arranged in front of the acting surface of the latter, for the purpose of securing
rapid and reliable ignition substantially as herein shown and described.
2. In the automatic gas lighting device referred to in the preceding claim the
provision of a platinum wire carrier c retained in place by friction and adjustable
in height, for the purpose of enabling the tension of the wires to be controlled sub-
stantially as herein shown and described.
Dated this 31st day of December 1897
WHITE & WOODINGTON,
Rooms 221-225, Birkbeck Bank Chambers, Chancery Lane, London, Agents.