Improvements in Lamps for Generating and Burning Acetylene Gas.
Year: 1897

page_text: Date of Application, 5th Oct., 1897-Accepted 5th Feb., 1898
[Communicated from abroad by CHARLES WILLIAM BECK, of 175, Dearborn Street,
Chicago, Illinois, United States of America.]
Improvements in Lamps for Generating and Burning Acetylene Gas.
I, WILLIAM HUMPHREY WHEATLEY, of the Firm of Wheatley and Mackenzie,
Engineers and Patent Agents, of 40, Chancery Lane, London, W.C., do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to improvements in lamps for generating and burning
acetylene gas, of the type wherein the gas is consumed directly or practically as
fast as generated, as distinguished from lamps or generators provided with a gas-
ometer or storage vessel in which the gas is passed previous to its transmission
to the burner.
Among the principal objects of the invention are to provide improved means
for maintaining an adequate and properly regulated supply of liquid to the car-
bide, it being understood that the rate of generation of gas is directly proportional
to such supply; to provide a relief reservoir adapted to receive the excess of gas
when the pressure exceeds a predetermined limit; to provide improved means
for conveniently opening and closing the generator and at the same time insure
a perfect gas tight joint at the point of separation and to provide a generally
The invention
improved and perfected generator of the character referred to.
consists in the matters hereinafter described and more particularly pointed out
in appended claims, and the same will be readily understood from the following
description reference being had to the accompanying drawings, in which,―
Figure 1 is an axial vertical sectional view taken on a diameter passing through
the gas pipe which conveys the gas to the burner.
Figure 2 is a horizontal sectional view, taken on the indirect line 2-2 of
Figure 1 and looking downwardly.
Figure 3 is an enlarged fragmentary detail in side elevation of the locking
devices of the clamping strap shown in Figure 2.
Figure 4 is a horizontal sectional view, taken on line 4-4 of Figure 1.
Figure 5 is an axial section of the nozzle, showing the end of the valve plug
and connected rod.
Referring to said drawings, A designates as a whole the generator, comprising
as its main or principal parts a body or font A', a distributing chamber B arranged
concentrically within the font, a carbide chamber or cage surrounding said dis-
tributing chamber, a water reservoir D mounted upon the upper end of the
font, a pressure chamber E arranged concentrically with, and above, the distribut-
ing chamber and a collapsible relief chamber or reservoir F arranged immediately
beneath the font and within the base of the generator.
First describing the main body or font A¹ which constitutes the generating
chamber, said part is cylindrical in form and consists of two members a a¹,

page_text: respectively, conveniently constructed to separate in a horizontal plane at a point
a short distance below the top of said receptacle. The upper member is provided
with an end closing wall which also forms the bottom of the
reservoir and is centrally apertured to receive the. open upper end of
the distributing chamber B; the latter being rigidly secured thereto
by means of a collar which is soldered or otherwise permanently secured within
said aperture of the end wall and internally screw-threaded to receive the corres-
pondingly threaded end of the distributing chamber.
The joint by means of which the upper and lower members of the font are
united is of novel construction, the extreme end portion of one member (in this
instance the lower one) being reduced. so as to telescope within the opposite
member, as indicated at a, and provided with an annular shoulder as which
serves to limit the distance to which it may telescope within.the receiving member..
Within the interfitting parts, thus constructed are formed oppositely disposed.
bayonet locks a6 a7 whereby the members are held securely together, but may
be readily separated.
In order to render the joint gas tight, the lower edge of the upper member and
the corner or angle of, the annular shoulder as are beveled oppositely in such
manner as to form, when the parts are brought together, an external V-shaped
groove, as indicated at a8 a, which extends entirely around the receptacle. Within
this groove is placed a packing ring a¹o, preferably of rubber. Over the packing
ring is arranged to fit a clamping or compressing ring designated as a whole by G
and consisting of an open ring or band of sheet metal g, provided with an internal
longitudinal groove g which in part receives the packing ring, and is provided
also at each end with an outstanding lug or ear 2 g, respectively... To one of
said ears is pivotally attached a toggle lever g', to which latter is in turn pivoted
a link adapted to hook over and engage any one of a series of notches of formed
upon the remote side of the opposite ear g²; that side of said ear within, which the
notches are formed 'being made inclined so that each succeeding, one of the
notches from the outermost toward the base of the ear or lug is more remote from
the point of-pivotal attachment of the link, thereby affording means for varying
the size of the compressing ring by hooking the link in the various notches. In
order that the packing ring may be held compressed throughout that portion
which extends between the ears, one of the latter is secured a short distance
back from the end of the band and the other is arranged to project beyond the
end of the band to which it is attached a corresponding distance, thereby enabling
the ears to be drawn together or toward each other without bringing the ends of
the band into contact.
The lower member of the font is provided with an end closing wall all and
also with a flaring depending base flange at which depends some distance below
the end of the font proper and encloses a space within which is arranged the
collapsible relief reservoir F, hereinafter more particularly described.
Within the chamber A¹ is arranged an inner carbide holder or cage C which,
is also cylindrical but is of sufficiently smaller diameter than the outer casing
to provide a surrounding space c7 for the gas which serves as a jacketing to pre-
vent in a large measure the transmission of the heat caused by the slacking
of the carbide from the inner to the outer receptacles. Said inner cage is con-
nected with the outer-casing at the central part of its upper end only, and, to.
this end is centrally apertured at said upper end to receive the upper part of the
distributing chamber B which passes therethrough and holds the inner receptacle
in position through the medium of an annular flange b which clamps said end wall
of the inner receptacle to the overlying part of the collar a³, as indicated clearly
in the drawings. The inner receptacle is constructed to separate at a point
approximately in the same horizontal plane with the line of separation of the
outer receptacle, one part being arranged to telescope within the other and the
two members being united by means of bayonet joints in a manner substantially
similar to that hereinbefore described in connection with the outer casing, aš

page_text: indicated at c¹. The lower end of the carbide cage is made in the form of a
removable cap which is also connected with the body of the receptacle by means
of bayonet joints as indicated at c³:
I
In a generator in which the liquid is supplied to the carbide in regulated
quantities the slaked residue becomes soaked with the liquid and if the body of
carbide be agitated so as to mix the wet residue with the unslaked carbide, a
large volume of gas is rapidly generated. In order to prevent this I have shown
a spring pressed disk C₁ arranged in the upper part of the carbide receptacle so
as to rest upon the body of carbide and hold it compact but adapted to yield
upwardly by compressing a spring e as the carbide expands in slacking.
The reservoir 1), which, as herein before stated, is mounted upon the generating
chamber, is desirably and as shown herein provided with spherical sides and made
of relatively large diameter and correspondingly shallow in depth so as to reduce
the height of the generator as a whole to a minimum. A suitable filling
aperture is provided at the top of the reservoir, which is closed by a screw
cap
I*
:
The distributing chamber B consists of a cylindric or tubular chamber which
is arranged centrally within the generating chamber and extends throughout the
full height of the latter, the lower end being closed by an end wall b¹ while the
upper end is in open communication with the water reservoir D. Through the
side wall of the distributing chamber is formed a series of outlet apertures 63
spaced at uniform intervals apart throughout the height of said chamber and in
the present instance arranged in a vertical row. In order to control the discharge
through said outlet apertures a valve sleeve B₁ is arranged to telescope and fit
accurately within the distributing chamber and which is provided with a
plurality of series of apertures 63 adapted to be successively brought into com-
munication with the outlet apertures of the distributing chamber so as to register
progressive areas of discharge as the valve sleeve is rotated upon its vertical
axis. In the particular arrangement shown herein, the apertures of the distributing
chamber are arranged in a vertical row and the valve sleeve is provided with
apertures arranged in circumferential rows in horizontal alignment with the
several apertures of the distributing chamber and with the apertures of each
succeeding lower row in vertical alignment with those above.
In operation the valve sleeve is rotated step by step and the uppermost circum-
ferential row contains as many apertures as there are steps of movement in one
direction of the valve sleeve less one, the next lower row contains one less aperture,
and so on throughout the several series. By means of this arrangement when
the valve sleeve is in one certain position all of the outlet apertures of the dis-
tributing chamber will be closed, when rotated or moved forward a step a single
one of the uppermost row of apertures 63 will be brought into register with the
uppermost outlet of the distributing chamber, when rotated a second step a second
aperture will be brought into register with the uppermost outlet of the dis-
tributing chamber and at the same time an aperture 63 of the next lower row of
the valve, sleeve brought into register with the next lower outlet of the distribut-
ing chamber, and so on until the outlets throughout the entire height of the
distributing chamber are all open. In order to still further regulate the outflow
of liquid from the distributing chamber the latter is provided with a wrapping
of fibrous or absorbent material, such, for instance, as felt, as indicated at 64;
the wrapping being preferably composed of an inner layer of felt, then a wrapping
of wire gauze or foraminated metal and a second outer wrapping of felt.
Means for manually rotating the valve sleeve step by step, and also means for
automatically lifting or moving it endwise so as to entirely shut off the liquid
supply whenever the gas pressure exceeds a predetermined limit, are provided as
follows: Ba designates an operating rod removably but rigidly connected with
the upper end of the valve sleeve centrally thereof and arranged to extend axially
up into the pressure chamber herein before referred to. The said pressure chamber

page_text: consists of an open-ended cylindric chamber seated in the top wall of the reser-
voir D with its axis vertical and arranged to extend some distance downwardly
within the reservoir, and also to project at its upper end outside of the reservoir;
such seating being conveniently accomplished by means of a flanged sleeve E¹
which is soldered or otherwise permanently secured within the top wall of the
liquid reservoir and arranged to depend within the latter and internally screw-
threaded to receive the said pressure chamber. At its extreme lower end said
sleeve E is provided with an inturned flange e against which the lower end of the
pressure chamber is adapted to impinge. E designates a thin flexible diaphragm
made of some suitable material unaffected by the action of the gas, such, for
instance, as thin sheet metal, having its periphery secured between the inturned
flange e and the end of the pressure chamber.
At the point where the operating rod B2 of the valve sleeve passes through
this diaphragm, it is provided with a connection e' which serves to render the
diaphragm liquid and gas tight at this point; the upper member of the con-
nection e¹ having the form of an elongated cap, into which the upper end of the
rod B is threaded. B³ designates a separate extension of the operating rod, the
lower end of which enters the upper end of cap and is headed therein in such
manner as to permit it to rotate and enable the rod B2 and connected valve sleeve
to be lifted thereby. The cap e² also permits the rod B³ to be moved downwardly
therein a limited distance without depressing the rod B2; the latter being normally
held in its lowermost position by means of a spring e3 which is interposed between
the cap and a partition e' through which the rod B³ passes. The diaphragm E²
is connected at its center with the rod B3 and is sufficiently larger than the part
of the chamber it spans to permit the center to rise or fall some distance under
internal pressure on the one side and the pressure of spring on the other.
e20 designates an air vent.
The upper end of the pressure chamber is closed by an elongated cap E³
threaded into the chamber at its lower end e¹0 and forming a nozzle, closed at its
upper end except for a gas passage ell therethrough. The upper end is provided
with a recess e¹² into which the gas passage opens and within which is seated a
burner tip e, the main cavity of which is filled with porous material e14. A
considerable portion of the upper end of the nozzle is formed of solid metal,
through which portion the gas passage extends and said passage is intersected
by a valve plug aperture e within which is seated a cock or valve plug E, pro-
vided with a transverse gas passage els adapted to be brought into or out of
register with the gas passage ell by rotation, in the usual manner. Said cock
is conical and provided with a truncated end e16 which terminates in a cavity e¹?
communicating with the main chamber of the nozzle, and upon said truncated
end is mounted a stud or wrist pin els eccentrically located with relation to the
axis of the cock. The upper end of a link jointed to the rod 133 is suitably
apertured and connected with said wrist pin so that the valve sleeve will be lifted
simultaneously with the shutting off of the gas from the burner by the turning of
the cock. In order to hold the cock to its seat a screw e19 is inserted through
the side of the nozzle and engages the cock axially thereof. Any suitable
chimney or globe support may be mounted upon the nozzle, as indicated at E5.
In order that the valve sleeve may be rotated step by step the exact distance
required to bring its several series of outlets into register with the outlets of the
distributing chamber, and in order that such step by step movement may be made
perceptible to the operator through the sense of feeling, means are provided as
follows: At its lower end the valve sleeve is provided with a downwardly pro-
jecting centrally arranged boss 65, through which is inserted a ratchet bar 66. In
the lower end of the distributing chamber, concentrically with the axis of the
valve sleeve, is secured a segmental shaped ratchet 67 having a series of upwardly
facing semi-circular ratchet notches 68. (See Figure 4.) One end of the ratchet
bar rests upon said segment and is adapted to co-operate with the notches therein
while the other end is turned downwardly at right angles, as indicated at 69, in

page_text: such manner as to contact with the ends of the segment and thereby limit the
extent of rotation of the valve sleeve in each direction. The lower end of the
boss 65 is provided with a rectangular socket 610 within which extends the end
of a vertical spindle 611 rotatably mounted in the end of the distributing chamber.
The lower end of the spindle extends through and below the end cap c² of the
carbide receptacle and is provided with a worm gear 618 which is actuated by a
worm 613 upon a spindle 614 which has a bearing at its inner end in a bracket 615
and extends radially out through the side of the outer casing and is provided with
a thumb-nut 616. By reason, of the rounded form of the notches of the segment
the valve sleeve may be forced around from notch to notch in either direction
through the medium of the operating spindle 614, the coiled spring e³ permitting
the valve sleeve to rise sufficiently, and at the same time the engagement of the
ratchet bar with the notches makes the several steps from notch to notch dis-
tinctly perceptible to the sense of feeling.
The gas which is generated within the carbide receptacle escapes from the latter
through apertures formed in the upper end thereof, or through the several
joints of the receptacle, which is not designed to be made gas tight, into the outer
receptacle or font and is conducted thence through a pipe H which extends up
through the liquid reservoir to a reducing valve I and from the latter to the
nozzle E3.
The reducing valve is of novel construction .and comprises a valve body having
upper and lower chambers i i¹, respectively, separated by a rigid partition 22
through which is arranged to slide the lower end of a vertically reciprocatory
valve stem 3. The upper portion of the valve body is made removable at a point
midway of the height or depth of the upper chamber, one part being threaded
upon the other, as indicated at 24, and said chamber is provided with a flexible
diaphragm suitably clamped or secured at its periphery between the meeting
parts of the valve body and connected at its center with the valve stem 23 by means
of suitable collars . In that part of the valve stem which extends below the
diaphragm and works through the partition is formed a longitudinally tapering
slot which is of decreasing cross-sectional area or capacity from the top down-
wardly, the construction and arrangement being such that when the valve stem
is at its uppermost position the lower end of the slot will be within or above the
partition and the passage thus completely closed, but as the valve stem descends
a passage of gradually increasing capacity will be afforded through the partition
by the tapering slot. In order to hold the stem and connected diaphragm
toward the lowermost limit of its movement so as to afford a relatively free
passage through the partition for the gas, a coiled spring is interposed between
the upper collar above the diaphragm and the lower end of an adjusting nut 29
which is threaded into the upper end of the valve body and through which the
end of the valve stem is arranged to slide freely. The upper part of the upper
chamber is placed in communication with the outer air by means of an aper-
ture, while the pipe leading from the generating chamber to said
valve communicates with the part of the upper chamber below the
diaphragm. The lower chamber of the reducing valve communicates with the
burner through a pipe H¹.
In order that the reducing valve may be readily removed from the generator,
that part of the pipe H which extends within the liquid reservoir is arranged
to telescope within an outer pipe H³ fixed permanently within the reservoir, the
point of entrance of the gas pipe within the outer pipe being rendered gas tight
by means of a stuffing-box h.
In order to equalize the pressure within the upper part of the liquid reservoir
and the generating chamber a vent pipe K is arranged to extend upwardly from
the generating chamber through the liquid reservoir and terminates within an
outer cap k which is mounted upon the top of said reservoir. This vent pipe is
surrounded by an outer pipe K' which also extends from the generating chamber
through the top of the liquid reservoir and is externally screw-threaded for

page_text: engagement of the said cap k, the arrangement being such that a screw-plug k¹
threaded through, said cap may be screwed down so as to completely close the
vent, pipe. A vent opening is provided in the outer pipe K¹ to afford-exit of
the gas to the interior of the reservoir.
"
***
In the use of generators of this and analogous types wherein the liquid is
supplied to the carbide in graduated quantities; it is found that the generation
of gas does not cease immediately upon the cutting off of the liquid supply. I
have, therefore, devised, an expansible relief reservoir which is so constructed
as to receive any surplus of gas which may be generated and hold the same as
long as the pressure, is excessive, but which will immediately return the gas to the
generator proper whenever, the pressure returns to the normal..
1. 379 9
designates said, relief reservoir, herein, shown as consisting of an elastic, bag,
preferably of rubber or rubber fabric, arranged; within the base of the generator
immediately, beneath the generating chamber and communicating with the latter
through a hollow, screw plug f which serves also to attach the, bag to the under
side of the generator. Beneath, the elastic bag is arranged a flat disk F1, which is
acted upon by a coiled expansion spring f¹ interposed between the under side
of the disk and the upper side of a cross brace or bracket f
The operation of the lamp thus described has been indicated in the foregoing
description, but may be briefly described as follows: In order to charge the
generator, the clamping ring is first removed, the lower part of the generator
disengaged from the upper part, the, lower, cap of the cabide, receptacle next dis-
engaged from the body thereof and a suitable charge of carbide placed within
said receptacle while the generator is held in inverted position. The parts are
next replaced, the generator righted and a suitable quantity of liquid charged
into the reservoir through the filling aperture, whereupon the generator will be
in readiness for operation and may be started by simply turning the thumb-
nut so as to rotate the valve sleeve a step and thereby open the outlet of the dis-
tributing chamber, and by opening the cock and igniting the gas at the burner
tip as soon as it begins to generate. Should it be desirable to augment the rate
of generation, the operating handle will be moved forward one or more steps as
found necessary. The gas generated in the generating chamber passes to the
reducing valve and through the latter to the burner, it being understood that if
the rate of generation is too fast the pressure will force the diaphragm of the
reducing valve and the valve stem connected therewith downwardly and thus
lessen the area of the passage to the burner and prevent an over supply to the
latter. At the same time the increased pressure within the generator will force
upwardly the diaphragm of the pressure chamber and lift the valve sleeve, thereby
cutting off the supply of liquid to the carbide and thus reducing and finally
stopping the generation of gas until the pressure returns to the normal. When
the cock is turned to shut off the gas the valve sleeve will be lifted through the
medium of the rods B2 and B3 and thus cut off the water supply from the carbide.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I déclare that what
I claim is:-
1. In a lamp, the combination of a gas generating chamber, a gas jet communi-
cating therewith, a liquid receptacle smaller in cross-section than the interior of
the generating chamber and arranged within the latter, so as to be exposed to the
contents of the generating chamber at its sides, pores in the side wall of the
liquid receptacle, and a compact absorbent body covering said porous wall, con-
structed to permit a slow seepage of the liquid therethrough.
2. In a lamp, the combination of a gas generating chamber, a gas jet com-
municating therewith, a liquid receptacle of less capacity than the generating
chamber and centrally disposed within the latter, the walls of said liquid chamber
being perforated throughout its height, and a tubular.. wick surrounding said
liquid receptacle, with the outer surface of which the carbide rests in contact.

page_text: 3. The combination to form a lamp for generating and burning acetylene gas,
of a receptacle to hold the slaking agent, a generating compartment to hold car-
bide, a gas jet communicating with the generating compartment and means for
controlling the flow of liquid to the carbide comprising an elongated
support arranged to project within the mass of carbide and a wick or covering
of absorbent material upon said, support, freely exposed to the carbide,
said wick being supplied with liquid from the liquid receptacle.
.
4. In a lamp for burning gas generated from calcic carbide and similar com-
pounds, the combination of a chamber for the compounds, a chamber for the
slaking fluid perforated for the passage of said fluid, a perforated diaphragm
fitting the perforated, wall of the fluid chamber and means for moving one of
said latter parts relatively to the other to register progressive areas of its open-
ings with the openings of the other part.
5. In a lamp for burning calcic carbide and similar compounds, the com-
bination of a chamber for the compound, a chamber for the slaking fluid, a perfora-
ted diaphragm closing the perforated area of the latter chamber, porous material
interposed between the diaphragm and the wall of the fluid chamber and means
for shifting the position of the diaphragm to register progressive areas of its
openings with the openings of the fluid chamber.
6. A lamp for generating and burning acetylene gas, comprising a compartment
for carbide, a liquid receptacle arranged in juxtaposition to the carbide receptacle,
double partition walls separating said receptacles, each apertured, and means
operated by pressure of the gas generated, for moving one of said partition walls
bodily with relation to the other to close said apertures when the pressure exceeds
a predetermined limit.
7. A lamp for generating and burning acetylene gas, comprising a compart-
ment for carbide, a liquid receptacle arranged in juxtaposition to the carbide
receptacle, double partition walls separating said receptacles, each apertured,
means operated by pressure of the gas generated, for moving one of said partition
walls bodily with relation to the other to close said apertures when the pressure
exceeds a predetermined limit, and means, manually operable, for shifting the
movable partition to bring the apertures into register.
8. In a lamp for generating and burning acetylene gas, the combination of
a carbide receptacle, a cylindric liquid distributing chamber arranged therein,
a valve sleeve arranged to fit within the distributing chamber and capable of
both rotary and endwise movement therein, means for rotating said valve sleeve
and means for moving the same endwise comprising a flexible diaphragm subject
to the internal pressure of the generator and a rod connecting the diaphragm
with the valve sleeve.
9. In a lamp for generating and burning acetylene gas, the combination of a
carbide receptacle, a cylindric liquid distributing chamber arranged therein, a
valve sleeve arranged to fit within the distributing chamber and capable of both
retary and endwise movement therein, means for rotating said valve sleeve,
means for moving the same endwise comprising a flexible diaphragm subject to
the internal pressure of the generator, a rod connecting the diaphragm with the
valve sleeve and a spring arranged to act upon said diaphragm in opposition to the
internal pressure.
10. In a lamp for generating and burning acetylene gas, the combination of
a carbide receptacle, a cylindric liquid distributing chamber arranged therein
with its axis. vertical, a liquid reservoir mounted above the carbide receptacle
and distributing chamber, a pressure chamber seated in the liquid reservoir con-
centrically with the axis of the distributing chamber and arranged to project at
its upper end, above the reservoir, a valve sleeve arranged to fit within a distribut-
ing chamber and capable of both endwise and rotary movement therein, an
operating rod connected with said valve sleeve and extending upwardly through
the liquid reservoir and pressure chamber and connected at its upper end with
means for lifting, the same, a diaphragm arranged within said pressure chamber.

page_text: and connected with the operating rod so as to impart endwise movement thereto,
said diaphragm being subject to the internal pressure of the generator at its lower
side and acted upon by a spring at its opposite side, a gas passage leading from
the generator to the burner and a reducing valve in said passage.
11. In an acetylene gas lamp, the combination of a chamber for the carbide,
a chamber for the slaking fluid, means for conducting the fluid to the carbide,
and means operated by connection with the stop-cock of the gas-duct whereby
the turning of the cock to shut off or turn on gas cuts off or turns on the feed of
fluid to the chamber for the carbide.
12. In an acetylene gas lamp, the combination of a chamber for the carbide,
a chamber for the slaking fluid, means for conducting the fluid to the carbide, a
valve controlling the flow of the fluid, a gas-duct leading to the burner, a stop-
cock in said duct, and a connection between said stop-cock and the valve, whereby
the turning of the cock operates said valve to cut off or turn on the feed of fluid
to the chamber for the carbide.
13. The combination of the font, the distributing chamber, the valve sleeve,
the stop-cock, the connecting rod, and the swivel coupling.
14. The combination of the chambered nozzle, the truncated valve plug having
a wrist-pin upon its truncate end, the screw holding the plug in place, the curved
pitman, and the cut-off valve.
15. In a generator for producing gas from a liquid and carbide, or analogous
solid, which expands during generation of the gas, the combination with a recep-
tacle for the solid, of a yieldably movable part which confines and holds the solid
in a compact body, and means for supplying a regulated quantity of liquid to
the solid.
16. In a lamp for generating and burning acetylene gas, the combination of
a carbide receptacle provided at one side with a movable wall or follower, and
a spring arranged to hold said movable part in yielding contact with the body
of carbide.
17. In a gas generator for carbides, the combination of a generating com-
partment within which the gas is formed, a passage leading therefrom to the
burner, an expansible relief reservoir in communication with the gas space, and
means preventing the inflation of the reservoir except when the gas pressure
exceeds a predetermined limit.
18. In a gas generator for carbides, the combination of a generating compart-
ment within which the gas is formed, a passage leading therefrom to the burner,
an expansible relief reservoir in communication with the gas space, and means
permitting the flow of gas to the reservoir when the pressure rises above a pre-
determined limit and adapted to return the gas to the generator when the pressure
falls.
19. In a gas generator for carbides, the combination of a generating compart-
ment within which the gas is formed, and an elastic relief reservoir in communica-
tion with the gas space.
20. The combination with a gas receptacle comprising separable parts, of
means for forming a gas tight joint at the line of separation comprising an
external groove formed in the receptacle coincident with the said line of separa-
tion, a packing strip arranged to rest within said groove over the joints formed
by the meeting members and a clamping strip arranged to hold said packing strip
compressed within the groove.
21. A reducing valve consisting of a valve body provided with upper and lower
chambers separated by a rigid partition, a valve stem arranged to reciprocate
through said partition provided in its part which reciprocates within the par-
tition with a longitudinal tapering groove of increasing cross-sectional area from
one end toward the other of the valve stem, a flexible diaphragm arranged to
divide one of the chambers of the valve body and operatively connected with the
valve stem, an inlet passage arranged to admit pressure to the valve chamber
containing the diaphragm on that side of said diaphragm which would tend to move

page_text: the latter so as to reduce the area of passage through the valve stem to the other
chamber, means arranged to act on said diaphragm in opposition to said movement
and an outlet passage leading from the chamber other than that in which the
diaphragm is arranged.
22. In an acetylene gas generator, the combination with the generating recep
tacle of a carbide holder arranged within said receptacle, and made smaller in all
its dimensions than the latter, whereby the carbide holder is enveloped with a gas
or air space which prevents the transmission of heat to the exterior receptacle.
Dated this 5th day of October 1897.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.