An Improved Automatic Lighting Device for Gas-burners.
Year: 1897

page_text: Date of Application, 28th Jan., 1897-Accepted, 3rd Apr., 1897
COMPLETE SPECIFICATION.
An Improved Automatic Lighting Device for Gas-burners.
I, HUGO BORCHARDT of 62 Königgrätzer-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 :-
Automatic lighting devices for gas-jets and, more particularly, for incandescent
gas light burners have before been proposed and the following is the principle upon
which they were based: An additional or secondary jet, ignited by means of a
platinum sponge was employed to heat a body which, by expanding, opened the
pipe by which the main burner was fed with gas; so that the gas issuing from
such pipe in its turn became ignited by contact with the secondary flame or jet.
Then, the further expansion of the body referred to had the effect of cutting off
the supply to the secondary flame; after which the main flame alone remained
burning.
Devices of this class as hitherto constructed are attended with the drawback,
that the mechanism which serves to turn on or off the gas supply is of an extremely
delicate construction and liable to get out of working order through becoming
obstructed by dust or other foreign matter or impurities.
Besides, the body which is to be expanded by heat must of necessity be adjusted
with perfect precision; a requirement which none of the lighting devices, that
have up to the present time been introduced, meet in anything like a complete
manner.
Now the subject of this invention is an improved automatic lighting device, in
which the remedy for the first of the inconveniences I have mentioned consists in
the fact that the entire mechanism for turning the gas valve on or off is located
within the gas piping, and consequently protected from any injurious external
influences, whilst the last mentioned defect is obviated by the novel arrangement
of the part carrying the body to be expanded; which carrier is not, as before,
immovably fixed in position, but is loose within a sleeve or socket and is supported
upon a set screw which may readily be raised or lowered and the carrier consequently
adjusted as desired.
In the accompanying drawings in which like parts are indicated by similar letters
of reference :-
Figure 1 is a sectional elevation of an incandescent gas burner having the present
invention applied thereto.
and
Figure 2 is a vertical section of part thereof taken at right angles to Figure 1
Figure 3 is a horizontal section taken on the line x-x of Figure 1.
a represents the base of the main burner which is adapted to be screwed on to
the gas fitting (not shown) and to the burner a is fitted a branch-pipe b c upon the
part of which is placed the secondary or lighting burner d, provided with a
platinum sponge e, and a carrier g, loosely placed upon a set screw o, but retained
in position by a sleeve or guides whilst a platinum wire fis suspended from the
said carrier g.
To the lower end of such wire fa rod his secured and this rod is located within
the branch-pipe c and is depressed by a spring m.

page_text: The rod at its lower end terminates in a ring or eye by which it engages a
lever i, one end of which is supported in the plug of the branch 6 whilst its other
extremity engages the rod k of the valve ; which arrangement leaves the lever i
a certain amount of play.
The valve is formed with two conical faces and the valve chamber * is
provided with corresponding seats and the disposition of the valve is such
that, when lifted it closes against the seat and cuts off the gas supply to the
main burner whilst, upon being lowered, it closes against the seat and checks
such supply to the secondary burner.
The operation of the arrangement above described is as follows:-
"When at rest, the mechanism assumes the position shown in the accompanying
drawings, that is to say, the cold platinum wire f which necessarily contracts on
cooling overcoming the resistance of the spring m, draws the rod h, together
with the lever i, in an upward direction, thereby lifting the valve against its
seat and closing the orifice through which the main burner is supplied
with gas.
This closing of the valve for the time being is perfectly tight, the tension of the
platinum wire which is considerable being transmitted by the lever i, with a certain
degree of resiliency, to the valve l.
Now when a tap or cock, fitted in the main supply pipe or gas fitting (not
shown) is turned on by hand; or if gas be admitted to the burner in any other
manner; the gas, passing through the perforations n (Figure 3) will flow laterally
around the pipe and into the valve chamber *; and thence past the valve seat 12
through the branches b and c, to the lighting or secondary burner d; being there
ignited by contact with the platinum sponge e.
The secondary or lighting flame now envelopes and heats the platinum wire f
and, owing to the expansion of such wire under the influence of heat the rod h
descends.
The valve k in consequence, gradually moves downward, thereby allowing the
gas to pass by the valve seat through the supply orifice of the main burner when
upon meeting the flame of the secondary burner d it becomes ignited.
The main flaine now still further heats the platinum wire f, so that the rod h,
lever and valve descend still further thereby allowing the valve to close upon
the seat and cut off the gas supply to the auxiliary or secondary burner d leaving
the main burner alone lighted.
When the flame of the main burner is extinguished, in consequence of its gas
supply being cut off in the ordinary manner, the operations above described are
repeated but in the reverse order; that is to say, the extinction of the flame of the
main burner results in the cooling of the platinum wire f, the consequence being
that the rod h, together with the lever i and valve rises, the latter closing
against the seat and the whole arrangement resumes the position illustrated in
the drawings.
The fact that the passage to the secondary burner d remains open whilst the
apparatus is at rest is immaterial, as, owing to the small sectional area of the
branch pipe which is further reduced by the rod h nearly filling the bore of
the branch c, and to the absence of pressure in the main supply pipe the supply
cock of which is turned off, no appreciable quantity of gas can escape.
The tension of the platinum wire f is adjusted in the manner required by means
of the set screw o.
It will be obvious that the platinum wire f might be replaced by another suitable
material and that the arrangement of the parts may be to some extent modified
without departing from the spirit of the invention.
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 for gas burners of that class wherein a body

page_text: (such as f) capable of expanding under the influence of the heat given off by a
secondary burner, operates a transmission mechanism to open the supply to the
main burner, whereupon the supply to the secondary burner is closed; the trans-
mission mechanism, consisting of a rod such as h and a lever such as i, enclosed
with a view to its protection from damage, within the gas piping, such as 6 c,
leading to the secondary burner substantially as herein shown and described.
2. In combination with the automatic lighting device referred to in Claim 1, the
loose arrangement of a carrier such as g of a body such as f wherein the lower end
of the carrier is enclosed in a sleeve or guide such ass and supported upon a set
screw such as o, for the purpose of enabling the said body to be readily and
precisely adjusted substantially as herein shown and described.
Dated this 28th day of January 1897.
WHITE & WOODINGTON,
27 Southampton Buildings, London, Agents.