Improvements in Apparatus for Administering Nitrous Oxide or, other Gas for Inhalation.
Year: 1893

page_text: Date of Application, 4th Mar., 1893
Complete Specification Left, 1st Dec., 1893-Accepted, 13th Jan., 1894
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Administering Nitrous Oxide or,
other Gas for Inhalation.
"".
I, WALTER SMITHARD, of Stretford Road, Manchester, in the County of
Lancaster, Dentist, do hereby declare the nature of this invention to be as
follows:-
The object of the invention is to simplify and make more efficient the construc
tion of apparatus used. by dentists and others for administering uitrous oxide or
other gas.
The valve or stand by which the gas passes from the steel cylinders is provided
with a plunger with tapered end fitting into a recess. The end closes the inlet tube
or aperture and the side of the plunger passes and closes the outlet tube. The
point is made of aluminium to prevent corrosion and the consequent leakage that
would result therefrom. The plunger is provided with a shoulder against which a
spiral spring bears to hold the plunger closed. It also tends to prevent leakage
in the lower chamber from or round the seating of the spiral spring.
The plunger is attached as heretofore to a pedal or other lever by which it is
operated and the gas passes through suitable tubes ports or openings from the necks
of the steel cylinders to the chamber or recess in which the end of the plunger is
placed.
The stand at or near the top is provided with a flange on both sides to support
or on which to rest the clamp which holds the steel cylinders or gas containers and
thus prevent tilting when the cylinder at one side is. lighter than the other or when
only one cylinder is used. And the coupling screw by which they are held iu
the clamp with a conical continuation instead of with a shoulder to add to its
strength.
The casting of the stand is provided with a screwed continuation or nozzle cast
in one piece therewith instead of with a nozzle screwed in-to receive the end of the
flexible tube by which the gas is conveyed to the patient.
The screwed lug at the top of the stand to receive the face piece is dispensed
with and a hole bored in the top of the apparatus to receive a suitable bracket or
stand which when not in use is removed and a small ornamental screw takes its
place.
An indicating dial provided with a finger or pointer or other recording appliance
is fitted to the front of the stand by which the number of administrations can be
recorded and thereby indicate the quantity of gas withdrawn from the cylinders.
The indicator need not be automatic but can be operated by the administrator
either by hand or foot in the latter case by connecting it by suitable lever and link
with the pedal.
The silencer is constructed with a special form of coupling joint which screws
into the nozzle of the stand and into the end of the tube and is in the form of a
hollow plug with a small hole for the passage of the gas. The tube is filled' with
carbon instead of glass wool and sponge to form a filter. It thus acts as a purifier
for the gas and as a silencer by preventing any rush of gas.
The inhaler or inhaling valve I construct with a threeway valve or appliance
whereby the valve may be opened to the gas and to the air, to the air only or to
the gas only so that the patient can inhale either gas or air and the gas or air as it
is exhaled will pass into the atmosphere or gas may be inhaled and when exhaled
pass again into the receiver which the patient can then re-iuhale. The appliance
is constructed with three openings or apertures that at one end connecting with the

page_text: gas that at the other with the atmosphere and a central one through the gas or air
is inhaled and through which the exhalations also pass. At or near the centre or
in other convenient position is placed a semi-circular disc or other diaphragm
extending about half way across the tube and in the tube is placed a sliding or
telescopic piece carrying two similar diaphragms or valves either of which cau be
moved to rest upon the first diaphragm to close the passage. One of these is rigid
and the other flexible the rigid one can be used to close the end of the apparatus
entirely below which it is placed and the flexible one to close the end of the
apparatus against a downward current or pressure but will open in the other
direction on suction being applied to the aperture above it.
These work below the central opening and the sliding piece also carries a bracket
to support a light valve above the central opening the spindle of the valve being
guided by the bracket. When the sliding piece is raised to close the lower end of
the appliance which connects with the gas the top valve is lifted clear from its
seating allowing a free passage both for inhalation and exhalation with the
atmosphere. When the sliding piece is moved to the bottom the bottom and top
valves are both in operation the bottom flexible valve rises to admit gas when the
pressure is reduced above it and closes again when the pressure is increased and
the top one is raised from its seat to allow the exhalation to pass to the
atmosphere. When in the central position the passage to the gas is maintained
open and the top valve cau be held closed by placing the finger on the spindle
thus allowing the gas to pass to and from the receiver to be re-inhaled several
times. The top valve may be made of vulcanite or other light material.
In the construction of the face piece I dispense with the leather outer covering
and form it wholly of rubber so that it may be capable of being more thoroughly
cleansed and I also make it of a shape or form that will offer but little or no
obstruction to the gag for this purpose I enlarge it below or on the under side and
also above or on the upper side curving it out both top and bottom instead of the
conical form at present adopted.
Dated this 3rd day of March 1893
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.
COMPLETE
SPECIFICATION.
Improvements in Apparatus for Administering Nitrous Oxide or
other Gas for Inhalation.
I, WALTER SMITHARD, of Stretford Road, Manchester, in the County of
Lancaster, Dentist, do hereby declare the naturo 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 :-
The object of the invention is to simplify and make more efficient the construction
of apparatus used by dentists and others for administering nitrous oxide or
other gas.
It consists essentially in constructing the apparatus with a stand to hold the
steel cylinders in which the gas is contained-and allow the gas to pass therefrom
for administration provided with a valve actuated by a pedal to control the
passage of the gas; a nozzle and tube for conveying the gas to the inhaler; a
bracket or attachment for holding the face piece when not in operation, which can
be removed when not required by the operator; an indicating dial and finger on
which the number of administrations from the cylinders can be recorded; a
silencer and purifier for preventing noise and preventing impurities passing
forward with the gas to the patient; an inhaler or inhalation valve, constructed
to permit, at the will of the operator, the inhalation of fresh gas at each

page_text: Fig. 1. Front elevation of the apparatus with the face-piece removed.
Fig. 2. Sectional elevation of same.
Fig. 3. Side elevation of the attachment for holding the face-piece, showing it in
position.
Fig. 4. Front elevation in section of top portion of stand containing the shut off
valve.
Fig. 6. Side elevation of same.
Fig. 6. Side elevation in section.
Fig. 7. Side elevation in section of face-piece and inhalation valve.
Fig. 8. Front elevation of face-piece.
The apparatus is constructed with a stand A at the head of which the steel
cylinders which contain the gas are suspended by the neck, the nozzles of the
aylinders fitting into the openings or apertures 6 being clamped or tightly held in
that position by the clamp B.
The stand is composed of a tubular upright part a screwed or otherwiso fitted
into a base plate A' and carrying at the top a head or upper part C in which the
'ports and valve are placed.
The head C is provided with a port or passage c leading from the apertures d
in which the nozzles of the containing cylinder are held to a central chamber or
passage d in which works a controlling valve and its spindle D. From this central
chamber d a second port or passage of leads through the nozzle C' to which the
tube e, which conveys the gas to the face-piece E is attached. The valve D is
preferably made in the form of a plunger with tapered end which fits into and
closes the mouth of the port or passage c and is capable of moving to and fro in
the chamber d. The point of the valve D is made of aluminium, aluminium
bronze or other metal not liable to corrosion, to prevent the wear and leakage
that would result therefrom. The valve or plunger D is provided with a shoulder
or collar d' against which a spiral or other spring F bears to hold it against its
seat at the aperture of the port or passage c. The spring F fits loosely into the
chamber and is held in position against the collar d' by the screw or gland f
-with a metallic and leather washer between-screwed into the bottom end of
the head C.
To the lower end of the spindle of the plunger D a connecting rod D¹ is
attached by a screw or other coupling. The lower end of the connecting rod D'
is connected to a pivoted lever or pedal G, by which the valve or plunger D is
drawn down to and the aperture of the port o opened.
The head C of the stand is provided externally with flanges 6', one on each
side, by which is supported or on which rests the clamp B, which holds the steel
cylinders or gas containers in position; these flanges prevent the clamp tilting in
securing the cylinders and render the fixing of them in position much more
expeditious. The coupling screw in the end of the clamp is proferably provided
with a conical continuation instead of with a shoulder or abrupt termination for
the purpose of giving additional strength.
On the side of the stand A. I place an indicating dial H, provided with a finger
or pointer h, by which the number of administrations can be recorded and thereby
indicate the quantity of gas withdrawn from the cylinders. The indicator need
not be automatic, as the inger à can be operated by the administrator either by
hand or it may, if desired, be connected by suitable lever and link with
connecting rod D' or with the pedal G.
On the top of the stand head C is fixed a bracket and cross bar I forming a
bandle by which the apparatus can be lifted or moved as required from place to

page_text: place. In the top of the bracket I is bored a hole to receive the screwed end of
the upright attachment 1' with a forked upper end to hold or support the face-
piece when not being operated with. When this attachment is not required to
be used, it can be unscrewed and removed and the hole into which it fits be closed
by the ornamental set-screw i.
The nozzle C to receive the end of the flexible tube by which the gas in
conveyed to the patient is cast in one piece with the stand head C instead of being
screwed thereinto as has hitherto been the case.
The silencer and purifier K is screwed onto the nozzle C'. It is hollow for the
gas to pass through and is fitted at one end with a plug with a small hole for the
passage of the gas and is filled internally with granulated cork and porous carbon
to prevent any impurities, such as particles of rust, passing with the gas from the
interior of the cylinders. It thus acts as a purifier for the gas and a silencer by
preventing any rush of gas or noise arising therefrom. The tube e is attached to
the silencer or purifier K by a ferrule K which slides over the end and is held in
position by a bayonet or other suitable joint.
On the tube between the end of the tube .and the face-piece E I place an
'inhaler or inhaling valve L. This inhaling valve is so constructed that it may be
opened to the gas and to the air, to the air only, or to the gas only, so that the
patient can inhale either gas or air and the gas or air as it is exhaled will pass into
the atmosphere or gas may be inhaled and when exhaled pass again into the receiver
'so that it can then be re-inhaled by the patient. The appliance is constructed with
three openings or apertures 2, 4, and . The opening at one end connecting
with the gas, the opening at the other with the atmosphere, and the central
leading to the face-piece E through which the gas or air is inhaled and through
which the exhalations also pass. At or near the centre or in other convenient
position in the tube M is placed a fixed or stationary semi-circular disc or other
diaphragm m extending about half way across the tube and in the tube M is placed
a sliding or telescopic piece N, carrying two similar diaphragms or valvos nn¹ by
moving the sliding tube N up or down to which these valves are attached either of
them may be brought to rest upon the diaphragm m to close the passage through
the tube M. The rigid diaphragm n when resting in the diaphragm m-closes the
aperture of the apparatus and shuts off all communication with the gas supply.
The flexible diaphragm or hinged flap n' when resting on the opposite diaphragm in
also closes the passage or aperture and prevents any down current but being
flexible allows the current of gas to pass upwards on suction being applied to the
apparatus above it. These diaphragms are placed and work below the central
opening. The sliding piece N also carries a bracket O to support a light valve o
above the central opening, the spindle of the valve being guided by the bracket.
When the sliding picco N is raised to. bring the diaphragm n. against the
diaphragm mito close the lower end of the appliance which connects with the gas
the top valve is lifted clear from its seating, allowing a free passage both for
inhalation and exhalation with the atmosphere through the aperture 1. When the
sliding piece N is moved to the bottom and the diaphragm rasts on the
diaphragm m the upper valve o and the Rexible diaphragm or valve are both in
operation the bottom flexible valve or diaphragm n' rises to admit gas when the
pressure is reduced above it and closes again when the pressure is increased aud
the top valve 'o, is raised from its seat to allow the exhalation to pass to the
atmosphere. When in the central position shown in the drawings the passage to
the gus is maintained open and the top valve o can be held closed by placing the
finger on its spindle and holding it closed, thus allowing the gas to pass to and
from the receiver to be re-inhaled several times. The top valve o may be made of
vulcanite or other light material..
.1
In the construction of the face-piece E I dispense with the leather outer covering
and form it wholly of rubber so that it may be capable of being more thoroughly
'cleansed and I also make it of the shape or form shown to avoid it coming in contact
• with the gag: I enlarge it below or on the. under aide and also above or on the

page_text: upper side curving it out both top and bottom instead of the conical form at present
adopted. The edges are formed with an air tube or pad e¹ to fit close to the face.
of the patient to prevent the escape of gas.
Between the inhaler and the tube is placed an elastic bag P of ordinary
construction in which the gas expanda.
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. Apparatus for administering nitrous oxide gas provided with a conical'
pointed plunger valve D controlled by a spring for opening and closing the ports.
in the head of the stand operated by a treadle at the foot of the stand substantially
as described.
2. Apparatus for administering nitrous oxide gas having the head C con--
structed with a flange such as b to maintain in position the clamp B by which.
the cylinders or gas containers are secured to the stand substantially as
described.
3. In apparatus for administering nitrous oxide gas the combination with the
stand which supports the gas containers of an indicating dial H by which the
number of administrations are recorded substantially as described.
4. An apparatus for administering nitrous oxide gas provided with a removable.
upright forked bracket 1' for supporting the face plate when not being operated'
with and an ornamental set screw i to take its place when removed substantially
as described.
5. A silencer and purifier for apparatus for administering nitrous oxide gas—
constructed of a hollow tube fitted at one end with a plug with a small hole and
filled with granulated cork and porous carbon substantially as and for the purposes
described.
6. An inhaling valve-for apparatus for administering nitrous oxide or other
gas-constructed with three openings one connecting with the gas to be inhaled,.
one with the atmosphere and the other with the face piece and provided with &
fixed diaphragm, and adjustable sliding piece carrying two diaphragms or valves.
to regulate the gas supply and a sliding valve to regulate the exhalations whereby
the gas can be inhaled and the exhalations from the patient can be controlled and
directed substantially as described.
7. An inhaler or inhaling valve for apparatus for administering nitrous oxide-
gas of tubular structure provided with three apertures 1, 1, and the fixed
diaphragm m of the sliding piece N, the diaphragm nn carried thereby whereby
the passage through the lower port of tube M may be opened or closed to the gas
and the light valve o carried by the bracket O whereby the upper port of the tube-
may be opened or closed to the external atmosphere substantially as described.
8. An apparatus for administering nitrous oxide or other gas having the several
parts constructed and arranged substantially as and for the purposes described and
shown.
Naha 1000
1334
WM. P. THOMPSON & Co.,
Manchester, Liverpool, and London, Patent Agents.
WM. P. THOMPSON & Co.,
Manchester, Liverpool, and London, Patent Agents.