Improvements in and connected with Apparatus for the Manufacture of Oxygen Gas.
Year: 1896

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 11 of the Patents, &c., Act, 1883), as required by
the decision of the Chief Examiner of the 29th day of June 1897.
T
PROVISIONAL SPECIFICATION.
Improvements in and connected with Apparatus for the Manufacture
of Oxygen Gas.
I, ALFRED SWEETSER, of 67 Croxted Road, West Dulwich, in the County of
Surrey, Consulting Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to further improvements in and connected with the
apparatus described in the Specification of prior Letters Patent No. 12245 of 1895
granted to me and comprises the various improvements hereinafter described.
According to one improvement I provide a filter of cotton wool or other
suitable material through which I pass the oxygen gas as it comes from the heat-
ing or generating tube or before it reaches the outlet tap, and therely avoid the
clogging of the passages in the tap and the jet which is apt to result when
unfiltered gas made in the manner described in the aforesaid specification is passed
through them.
Another improvement according to my present invention is the provision of
guides in the heating tube to guide the packets or cakes of oxygen yielding sub-
stance and to keep them clear of the heating surface and ensure a uniform heat
around the cakes. These guides are specially advantageous in apparatus in which
the heating tube is vertical.
In the above mentioned specification I describe the cakes of oxygen yielding
substance as being moved through the heating tube; I sometimes however arrange
to move the lamp or source of heat along a tube or row of retorts from one end
to the other, or I. arrange to move the heating tube or retorts while the lamp is
kept stationary. In the latter case the end of the tube will be connected to the
reservoir or bellows by a flexible connecting tube. In either case the tube will be
charged by a continuous string of packets or cakes of oxygen yielding substance,
the movement or feed of the lamp or of the tube or row of retorts being produced
by the movement of the gas reservoir, so as to render the production of gas
automatic and in accordance with the requirements. I find that in some instances
when the automatic movement for altering the relative positions of the oxygen
yielding substance, or part of it, and the source of heat, is worked direct from the
inovement of the gas reservoir there is apt to be caused a variation in pressure of
the gas contained in the reservoir which is objectionable, so I sometimes employ
clockwork or other motors or the weight of the cakes of oxygen yielding substance
themselves to feed the machine, the rate of admission only being controlled by the
movement of the gas reservoir, or by the pressure of the gas contained therein.
I find that the metal heating tube is soon attacked by the nascent gas and is
rapidly eaten away and rendered useless: accordingly to prevent such action and

page_text: to protect the tube I glaze the interior surface of the tube or I coat it with asbestos
paint or line it with nonoxidizable metal. In some instances I make the tube
entirely of porcelain or metal which is not attacked by the gas. When retorts
are used they can be treated in the same way to protect them from the action of the
nascent gas.
By a further improvement I provide an alarm bell or other audible signal to
ring or sound when the reservoir is nearly empty for the purpose of warning the
attendant that a further supply is needed."
I sometimes provide a metal case to enclose the blocks of oxygen yielding sub-
stance. In such instances I allow for the swelling of the substance when heated
by fluting the blocks or making them of irregular shape or otherwise so that they
do not entirely fill the cases. I provide the case with an enclosing cover extending
the entire length of the case. Holes are provided in the sides of the case to allow
the gas to escape, and to ensure the insertion of the case or cake into the heating
tube right side up I sometimes provide a projection at the side thereof or on the
cake of oxygen yielding substance itself and a corresponding notch in the gland
at the end of the tubes through which the cases are introduced.
In some instances the holes are normally closed and are only opened when the
pressure of the gas within the case pushes the cover outward. I preferably glaze
or paint the cases to protect them from the action of the nascent gas or I make
them entirely of porcelain or other suitable material.
I find that instead of covering the blocks of oxygen yielding substance with
asbestos paper or cloth, the asbestos can be applied in the form of a paint.
In some instances I provide an asbestos plug or cap at one end or at both ends
of the case, and in other instances I partially surround the block of oxygen vield-
ing substance with asbestos in addition to placing it in a case. I sometimes
supply the packets or cakes in a belt similar to a cartridge belt and arranged at
the end of the heating tube. The blocks are pushed into the heating tube
direct from the belt and are thus introduced right side up they having been
properly arranged in the belt.
According to my invention I also provide for placing a vaporizer for generating
a hydrocarbon gas or vapour within the same case as that containing the oxygen
producing apparatus so that the heat from the lamp for generating the oxygen
gas can also be used for heating the vapourizer:
In instances where a saturator is used I also place the saturator in the case of
the generating apparatus instead of in the lantern as heretofore. In this way I
avoid the objectionable plan of placing the saturator in the lantern and I am able
to use a larger and more efficient saturator than is practicable when it is placed
inside the lantern.
I sometimes utilize the heat of the newly generated oxygen gas for heating a
vaporizer or a saturator by passing the gas through a coil of pipes within them.
Dated this 9th day of March 1896.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION (AMENDED).
Improvements in and connected with Apparatus for the Manufacture
of Oxygen Gas.
I, ALFRED SWEETSER, of 67 Croxted Road, West Dulwich, in the County of
Surrey, Consulting Engineer, do hereby declare the nature of this invention
4

page_text: and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
This invention relates to further improvements in apparatus of the kind
described in the Specification of prior Letters Patent No. 12246 of 1895 granted
to me for the manufacture of oxygen gas.
In the said prior specification I described a method in which the oxygen yield-
ing substance is moved as required through the heating or generating tube in
order to keep up the supply of gas: according to my present invention I move
the heating tube or retort as required together with the contained oxygen yielding
substance intermittently over the lamp which is kept stationary. The heating tube
is charged by a continuous line of packets or cakes of oxygen yielding substance,
and the movement or feed of the heating tube which is effected by gravity or
clock work is controlled by the rise and fall of a part of the gas reservoir, so that
the generation of gas is ensured in accordance with the requirements.
To prevent any injurious action on the metal generating tube by the nascent
gas and to protect the tube I glaze the interior surface thereof or coat the said
surface with asbestos paint, or line the tube with non-oxidizable metal. In some
instances I make the tube entirely of porcelain or metal which is not attacked
by the gas.
I provide an alarm bell or other audible signal actuated by the descent of the
bellews or gas reservoir to indicate when the reservoir is nearly empty and so
warn the attendant that a further supply is needed.
I further pass the oxygen gas as it comes from the heating or generating tube
or before it reaches the outlet tap through a filter of cotton wool or other suitable
material, and thereby avoid the clogging of the passages, in the tap and the jet
which is apt to result when unfiltered gas made in the manner described in the
ahovenamed prior specification is passed through them.
A further napaovement according to the present invention consists in coating
the blocks of oxygen yielding substance with asbestos paint in lieu of asbestos
paper or cloth as heretofore.
In instances where 'a saturator is used instead of placing it in the lantern as
heretofore I place it in the generating apparatus which is a more suitable place
for it and enables a larger and more efficient saturator to be used than is practicable
when it is placed inside the lantern.
In order that 'my invention may be clearly understood I have represented
an apparatus constructed in accordance therewith in the accompanying drawings
of which
Figure 1 is a side elevation of the apparatus.
Figure 2 is an end elevation, and
Figure 3 is a plan thereof.
Like letters of reference indicate the same parts in all of the figures.
A is a tube or retort in which the oxygen gas is generated, B is a lamp for heat-
ing the tube A. Cis a flexible tube for conducting the gas from the tube or
retort A to the condenser D. E is the pipe leading from the condenser to the
bellows reservoir F, and G is a tank containing water to ensure the required
pressure of gas in the reservoir F. C is the 'oulet pipe for the gas.
The reservoir F stands in a case II to the sides of which, upright guides I and I'
are attached for the purpose of guiding the upper part of the apparatus in its
ascent and descent when the reservoir is being fillel or emptied; J, J' are guide
rollers carried in brackets or cheeks mounted on the tank G and engaging with
ribs on the inner sides of the said guides I I'.
The tube A is supported in an inclined position upon rollers K carried by
pillars K' mounted on the tank G so that it may descend by gravity when required
as hereinafter explained. For the purpose of regulating the descent of the
generating tube it is provided at its underside with two rows L and M of pro-
jeetions or teeth which are alternately engaged by one or the other of two pallets N

page_text: and carried by a slide P. The generating tube A cannot descend until the
slide P carrying the pallets is moved so as to release the tooth L in contact with
the pallet N; the generator then descends until arrested by the other pallet O
which at this time obstructs the path of the next tooth in the other row M. The
slide P is moved for this purpose by the spring Q attached at one end to the
said slide, and at the other end to one of the standards carrying the supporting
and guiding rollers for the generating tube. When the generating apparatus is
near the upper ends of the guides I, I the slide.P is prevented from yielding to
the pull of the spring Q by the right hand guide I' with which the inclined end
of the slide is then in contact, but as the quantity of gas in the reservoir decreases,
the upper part of the apparatus descends until the end of the slide 1' arrives
opposite a slot S in the guide I' whereupon the said slide is caused by the spring Q
to enter the slot S in the guide I¹ and so to withdraw the pallet 0 from its engage-
ment with a tooth in the row M and allow the reservoir to descend until arrested
by the contact of a tooth of the left hand row L with the pallet N. A fresh
iortion of the oxygen yielding substance is then subjected to the heat of the flame
from the lamp 13; the oxygen gas evolved is led through the tule C to the con-
denser D, where any vapour it may contain is condensed on the walls thereof.
From thence the gas is conducted through the tube E into the reservoir F which
it, inflates, thus causing the generating apparatus to ascend. When the inflation
of the reservoir begins, the upper part of the apparatus rises so that the inclined
end of the slide 1' again comes in contact with the top of the slot S and the slide
is forced back against the tension of the spring Q so that the engaging tooth in
the row L is allowed to escape past the pallet N and the pallet is again brought
opposite one of the teeth in the right hand row M, the slide being thus again set
ready to be moved outward at the next descent of the apparatus.
Should the supply of gas be sufficient to cause the generating apparatus to
continue rising the flame of the lamp is diminished by means of a sleeve T sur-
rounding the wick tube of the lamp B and normally held below the top of said
tube. The said sleeve T is raised by one extremity of a bell cranked lever U
pivotted on the pin of the guide roller J and having its other extremity adapted to
be operated by a projecting block or cam V fixed to the guide I. By the raising
of the sleeve T the same effect is produced as if the wick were pushed or racked
down into the wick tube; that is to say the size of the flame is decreased, and
consequently the rate of evolution of oxygen within the generating tule is
diminished."
Should the evolution of gas be so rapid that the apparatus rises quickly to the
top of the guides I and I before the check due to the diminution of the lamp
flame has become appreciable, a valve W opening inward and placed in the top
of the reservoir F is opened by the contact of its rol X with a stop Y at the top of
the guide I. By this means the danger of excessive pressure in the reservoir is
averted.
The alternate rising and falling of the upper part of the apparatus and the
intermittent descent of the generating tube between the guide rollers K continues
until all the available oxygen is driven from the substance in the said generating
tube.
The attendant in charge of the apparatus is apprised of the exhaustion of the
oxygen yielding substance by means of a bell which is struck by a hammer
attached to a spring controlled lever a the tail of which is depressed by a pin
carried on the tank G, when the apparatus has descended sufficiently far. A fresh
supply of oxygen yielding material may then be inserted in the tube A. before the
supply of oxygen in the reservoir has run out.
When the filter hereinbefore referred to is employed, I prefer to connect the
pipe C to the inlet thereof and the outlet of the condenser 1 in any suitable manner
The said filter has preferably tlie shape of a short cylinder divided circumferentially
into two parts which may be tightly jointed by screwing or otherwise. The inle
is at one of the flat ends of the said cylinder and the outlet at the other.