Improvements in Cocks for Mixing Gas and Air.
Year: 1890

page_text: Date of Application, 23rd Oct., 1890
Complete Specification Left, 17th June, 1891-Accepted, 18th July, 1891
PROVISIONAL SPECIFICATION.
Improvements in Cocks for Mixing Gas and Air.
I, RICHARD GOEHDE, of No. 12, Leipziger Platz, Berlin, Kingdom of Prussia,
Engineer, do hereby declare the nature of this invention to be as follows:-
:-
My invention relates to cocks by means whereof a mixture of gas and air is
produced for feeding burners of heating-apparatuses, and its object is to prevent
explosions from occuring in the burner and the parts connected therewith when
the burner is lit or extinguished.
For this purpose I arrange in the pipe connecting the gas-cock and the burner,
an aperture for the induction of air, and I attach to the plug of the cock a sluice or
slide-valve, adapted to open and close the said aperture as the plug is turned. This
sluice or slide-valve I put in such position relatively to the plug that, previous to
the admission of air, there will pass to the burner a small quantity of gas which is
sufficient, after having been lit, to produce a small kindling flame. When there-
upon the plug and the valve are turned further, the quantity of gas flowing to the
burner increases, while at the same time air is admitted in view of obtaining the
mixture of gas and air which is to feed the flame. On turning off the cock, first
the supply of mixture of gas and air is stopped and then the supply of pure gas.
The air-admitting valve may, however, also be attached rotatively to the plug
of the cock and further connection established by a driving pin on the plug and a
shoulders on the valve, so that gas will be admitted first and turned off first.
In view of drawing in air by the gas-current, the gas is conducted into the pipe
connecting the cock and the burner, through a nozzle projecting into the said pipe.
Moreover, the cock is advantageously provided with a spring catch whereby the
plug and the valve are arrested during their forward rotation just before air is
admitted, this catch requiring to be released by hand before the plug can be
rotated further.
Deted the Twenty-third day of October 1890.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Cocks for Mixing Gas and Air.
I, RICHARD GOEHDE, of No. 12, Leipziger Platz, Berlin, Kingdom of Prussia,
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:—
My invention relates to cocks by means whereof a mixture of gas and air is
produced for feeding burners of heating apparatuses, and. its object is to prevent
explosions from occurring in the burner and the parts connected therewith, when the
burner is lit and when it is extinguished.
The method employed for this purpose consists in first admitting to the burner a
small quantity of gas only, from which, on being lit, a kindling-flame is obtained,
and in subsequently causing the mixture of gas and air to be formed, which is there-
upon ignited by the said kindling-flame.
In the annexed drawing is represented a cock carried out according to my
tion

page_text: Fig. 1 is a vertical section and Fig. 2a sectional plan, both showing the cock
entirely closed.
Fig. 3 is a sectional plan, the full lines whereof represent the cock open for
admission of gas only, while by the broken lines is indicated the position which the
inovable parts have when the cock is open for the admission of both gas and air.
Fig. 4 is a top view of the cock,
Fig. 5 a sectional elevation of a modified arrangement, and
Fig. 6 a bottom view corresponding to Fig. 5.
2
^ !
Referring to Figs. 1 and 2, a is the plug having the orifices and b', the
gas
supply-pipe, and the pipe connecting the cock to the burner (the latter not being
shown in the drawing). At the underside of pipe is arranged an aperture p for
the induction of air, and to the square bottom stem a of the plug a is fixed a sluice
valve having an extension with slots, adapted to register with aperture p. From
the cock projects into the pipe q a nozzle t, so disposed relatively to the aperture p,
that when the latter is open and gas passes through the nozzle, the current of the
gas will draw in air through aperture p, whereby the mixture of gas and air is
formed. If air is supplied under pressure, the nozzle may be dispensed with.
The said sluice valve is secured to the plug in such position, that it will keep the
aperture p closed when the cock is closed and while the plug is turned into the
position shown by full lines in Fig. 3,.in which, the orifices 66' of the plug are open
to the extent necessary for allowing the gas required for feeding the kindling flame,
to pass to the burner.
If thereupon the plug and the valve are turned further, the quantity of gas
flowing to the burner increases, while at the same time the slots of the valve comes
into register with aperture p, so that air can pass in through the latter, and the
mixture of gas and air is obtained, which is now to feed the flame. The length of
the slots is such. that more or less gas can be turned on without, altering the
induction of air. Provided the orifices of the burner are made small enough,
relatively to the quantity of gas-mixture flowing through them, as that the speed
of the currents of mixture is always greater than the speed with, which the flame
is apt to propagate in the mixture, no explosion by a leaping-back of the flame can
occur.
On turning off the cock, first the supply of air is intercepted, thus allowing the
pipe to become filled with the non-explosive pure gas before the current of
gaseous combustible is stopped entirely, and then the gas is shut off for extinguishing
the flame.
T
In order to obtain the complete filling of the pipe y with pure gas when the
burner is to be lit or to be extinguished, it is necessary to stop a moment
rotating the plug after the gas alone has been turned on. In view of providing
security for such stoppage, and of causing the same to be brought about when the
plug is in the proper position, the cock. is furnished with a spring catch, consisting
in a small elbow-lever 12 pivoted to the plug-handle c, Figs. 1 and 4, spring w
pressing on the arm of said lever, and a notch formed, by the shoulders d d
on the
shell of the cock, the said notch being so arranged that when the arm of the
lever engages therein, the plug will be in the position in which it requires to be
stopped. By a pressure on the thumb-plate the arm may thereupon be
disengaged for allowing the plug to be turned further.
arresting the plug in its end-positions.
are shoulders for
Figs. 5 and 6 show an arrangement of the cock in which the air-admitting sluice-
valve is attached rotatively to the plug a, by being placed with its boss or eye, r
on a bush c¹ being round on the outside and fitted on the plug-stem a°. The .valve
is rotated by means of the arm f fixed to the stem aº and adapted to act according
to its direction of motion against either of the two studs jj inserted into the valve.
With this arrangement the gas is admitted first and turned off first, which answers
the purpose if the air is introduced under pressure. h is a spring pressing on the
valve in order to prevent the same from being shifted by the bush eithrough the
friction between it and the valve.
ין!
x and
y
2.

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. For producing a mixture of gas and air to be supplied to a gas-burner, the
combination of a gas cock having the plug a, pipe q leading from the cock to the
burner and having an aperture p, and sluice-valve fixed to the plug a and so
arranged relatively to the orifices of the plug and to the air induction aperture p
that when the plug is turned from its closing position, there will first be admitted
gas and thereupon air, and that when it is turned the other way, first the air will
be shut off and then the gas, substantially as described.
2. The combination, with the mixing cock covered by Claim 1, of the nozzle t
projecting from the gas-cock into the pipe q and so arranged that the current of
gas issuing from the nozzle will draw in air through the aperture p, substantially as
specified.
3. The modification of the mixing-cock covered by Claim 1, which consists in
arranging the sluice-valve r movable relatively to the plug of the cock, and
providing the said plug with an arm adapted to act alternately against two
projections on the valve, substantially as and for the purpose described.
Dated the 17th day of June 1891.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.