Note: Descriptions are shown in the official language in which they were submitted.
~ 2
Docket No. DF-445
PRESSURE ~EGULATOR ASSEMBLY WITH IMPROVED CARTRIDGE
. .
SPECIFICATION
Field of the Invention
This invention relates to pressure regulatorsO More
particularly, it relates to pressure regulators such as are
employed on cylinders of compressed gases like oxygen in
which a settable lower pressure is controlled by an adjustable
spring mechanism and in which the gas is ~hrottled to the
low pressure from a high pressure.
Description of the Prior Art
The prior art has seen the development of a wide
variety of pressure regulators for reducing discharge
pressure from high pressure cylinders of compressed gases
such as oxygen to the low pressure of only a few pounds per
square inch (psi) as in hospital oxygen systems, torches,
and the like. Basically these regulators have consisted of
a ~artridge, or core assembly, having a poppet~ adjacent a
seat, to control flow as necessary to attempt to effect
balanced forces between a heavy spring opposed by a diaphram
to which low pressure is applied. Patents such as U.S.
3,586,037 showed the ways of compensating single stage
pressure regulators to obtain accurate regulation regardless
of what the inlet pressure was. The later filed patents
such as U.S. 3,812,877 and its divisional U.S. 3,906,982,
described apparatus for overcoming the significant friction
that accompanied the long expanses of metal-to-metal contact
in many of the prior art regulators. Still later ones such
as U.S. 4,257,450 showed pressure regulators having a lost
motion connection so as to obtain reliable complete valve
closure at every shutoff regardless of whether or not there
were particles of carbon or the like adjacent the seat of
the regulator.
One of the problems that has persisted in this field of
-
-2-
pressure regulators and has not been satisfactorily solved
is that of the vibration induced through resonance, or
vibrations, caused by the high pressure gas flowing past a
valve poppet as it nears its seat. This vibration i9 very
destructive to the valve seat, particularly where hard seats
are employed. Moreover, it produces a noisy vibration
called "singing".
Summary of the Invention
Accordingly J it is an object of this invention to
provide a pressure regulator assem~ly having an improved
cartridge that eliminates the destructive and noisy vibration
of a poppet with respect to a seat when throttling gas flow.
Specifically, it is an object of this invention to
provide a pressure regulator for reducing gas pressure from
a high pressure cylinder of the gas to a low pressure
end use in which a poppet is opened when additional gas flow
is required as sensed by a regulator spring opposing a
diaphram subjected to the low pressure and in which the
poppet is closed against the seat when the pressure is
adequate and in which the improved cartridge of the regulator
eliminates destructive and noisy vibration referred to as
"singing" when gas flow is needed.
These and other objects will become apparent from the
descriptive matter hereinafter, particularly when taken into
conjunction with the appended drawings.
In accordance with this invention, there is provided an
improvement in a pressure regulator for reducing pressure
from high pressure to a low pressure in which the regulator
includes a valve body, seat, poppet, adjustable spring and
diaphram member in the usual type regulator construction.
The improvement is characterized by having an improved
cartridge in which there is included a poppet that includes
a centering extension shaft extending to the low pressure
side of the valve seat and a larger diameter shaft in
communication with the high pressure in the chamber and
~ 7
--3--
having the valve seatinclu~eacentering upper protrusion
that closely engages the centering extension shaft of the
poppet with at least three and no more than six slots
disposed substantially uniformly thereabout such that gas
can flow about the valve poppet centering extension shaft
through the valve seat without inducing destructive and
noisy vibration when gas flow is called for by the regulator.
In the preferred embodiment, there are four slots
disposed diametrally opposite each other for balanced
loading on the poppet and obtaining good flow characteristics.
Brief Description of_ he _ awings
Fig. 1 is a partial cross sectional view of the pressure
regulator in accordance with one embodiment of this invention.
Fig. 2 is a cross sectional view of the improved
cartridge of Fig. 1.
Fig. 3 is a top view of the valve seat of Fîgs. 1 and
2.
Fig. 4 is a cross sectional view taken along the lines
IV-IV of Fig. 3.
Description of Preferred Embodiment(s)
In Fig. 1 there is illustrated a cross sectional view
of the regulator 11. Regulator 11 comprises the main sub-
assemblies of body 13, regulator 6ap 15 with its adjustable
spring 17, diaphram means 19 and cartridge, or core assembly,
21.
The body 13 has inlet passageway 23, inlet chamber 25,
outlet passageway 27 and outlet chamber 29. As illustrated,
the inlet and outlet passageways 23, 27 are threaded so as
to receive a properly threaded male insert, such as a
nipple, threaded insert or the like. As is recognized, such
threads may be appropriately right handed or left handed
depending upon the nature of the gas and to prevent inadvertently
attaching the regulator 11 to an incorrect cylinder of gas.
For example, regulators that are employed on inert gases may
~ 3
-4-
have substances, such as oil or grease, that would be
incompatible with reactive gases such as o~ygen. Coded
threading is frequently employed to prevent inadvertent
wrongful attachment and is employed in the body of this
regulator.
The inlet passageway 23 and the inner chamber 25 may be
subjected to the high pressure before it is regulated to the
lower pressure and are designed to handle the high pressure~
Conversely, the outlet passageway 27 and the outlet chamber
29 ordinarily are subjected to only the lower~ regulated
pressure to which the regulator is set by the adjustment
setting to the regulator cap 15 and its adjustabl~ spring
17.
The regulator cap 15 is removeably affixed to the body
13, as by threaded connections and has a compression adjusting
means illustrated by threaded stud 31 screwed through tapped
bushing 33 which is, in turn, screwed into the appropriate
threaded aperture in the cap 15. The adjustable spring 17
has a bottom plate 35 contiguous with the diaphram means 19
and is adapted to move therewith as pressure changes in th~
outlet chamber 29. The spring 17 has a compression plate 37
at its top that co-engages and is responsive to the pressure
nut 39 on the threaded stud 31. A handle 41 is provided for
rotating the stud 31 to increase or decrease compression
and, consequently, increase or decrease the low pressure
that is regulated downstream of the regulator 11.
The adjustable spring 17 is made of any material that
will have the required strength. For example, it may be
made of steel since it is not subjected to the corrosive
gases. The usual type springs may be employed in this
regulator and no special alloys or springs are required.
The diaphram 19 is held in place intermediate the top
15 and the body 13. It engages the valve stem of the
cartridge 21 and is contiguous to and moves concurrently
with the bottom plate 35. Ordinarily the diaphram will be
formed of a tough flexible material such as Neoprene or
-5-
other fluid impermeable material. The diaphrams employed in
the prior art may be employed in this invention and no
special material of construction is required.
The main improvement of this invention lies in the
improved cartridge 21 and its included poppet 43 and seat
45; also shown in Fig. 2. The improved cartridge screws
into its receptacle and sealingly seats on gasket 46. As
can be seen more clearly in Fig. 2, the poppet 43 includes a
centering extension shaft 47 that e~tends to the low pressure
side of the valve seat 45. As illustrated, the poppet
includes a larger diameter shaft 49 communicating with the
high pressure side of the valve seat 45. The poppet 43
includes an annular shoulder 51 to provide a bearing surface
for a biasing spring 53. The ~iasing spring 53 biases the
15 poppet toward the seat 45 when the forces between the ~
diaphram means 19 and the spring 17 are equal. A thermoplastic
base plug 54 reciprocally receives the larger diameter 49
and is, in turn, disposed within the tubular base 55. A
filter 57 is provided to filter the incoming gases.
The usual materials or workmanship can be employed in
this invention. For example, the respective poppets,
bushings, cartridge elements and the like may be formed from
brass, stainless steel or other metallic materials appropriate
to the type of gas being flowed therepast. Where there is
very little compressive and tensile stresses, thermoplastic
materials can be readily employed. Typically, the thermoplastic
materials may be Nylon, Orlon, polyethylene, or the polyhalogenated
hydrocarbon materials. It is desirable, however, that the
poppet 43 have low friction with respect to elements against
which it will reciprocate, such as the base plug 54 and the
seat 45.
The seat 45 includes a centering upper protrusion 59
that closely engages and co-acts with the centering extension
shaft of the poppet to prevent the destructive and noisy
vibrations that are ordinarily induced when gas flow is
called for by a regulator. The valve seat 45 has a plurality
~ a~
-6-
of at least three and no more than six slots formed into the
upper protrusion 59 and disposed substantially uniformly
about the centering extension shaft 47 f~r allowing gas to
flow when it is called for by the regulator 11. ~s illustrated,
four slots 61 are provided and form the preferred embodiment
in which the respective slots are diametrally opposite each
other as shown in Fig. 3O Thus, ~he respective four shafts
divide the centering protrusion 59 into four respective
centering shoulder tabs 63, Figs. 3 and 4. The valve seat
45 provides a sharp annular ring 65 against which to seat
the frustal conical shoulder 67 of the poppet 43. ~ surrounding
annular shoulder 6~ allows the seat to be held intermediate
an interior cage 71, Fig. 2 and the outer bushing 73. ~s
can be seen in Fig. 1, the entire cartridge assembly can
then be screwed into a threaded receptacle in the body 13.
The valve seat is preferably formed of a thermoplastic
material that is resistant to corrosion and erosion by the
gas being regulated. For example, it is preferred that
tough thermoplastic material such as Nylon, Orlon3 Delrin
and Kel-F be employed. When oxygen is employed, the Kel-F
is a preferred type cf material from which to form the valve
seat 45. As is recognized, Kel-F is chlorotrifluoroethylene
that is polymerized into the desired hardness. It is
commercially available from DuPont and can handle gases that
would be corrosive to other thermoplastic materials as well
as to metals.
In operation, the low pressure regulator 11 is connected
with a high pressure cylinder of gas (not shown) by inlet 23
and appropriate conduit connection (also not shown). With
zero pressure set by compression adjusting means in regula~or
cap 15, the pressure in high pressure chamber 25, coupled
with urging from spring 53, forces the poppet to engage the
frustal conical shoulder 67 with the seat ring 65 of the
valve seat and block flow of gas.
When the threaded stud 31 is screwed downwardly,
pressure is applied to spring 17 and force is transmitted to
--7--
unseat the poppet shoulder 67 by the force from diaphram
means 19, bottom plate 35 and centering extension shaft ~7.
Outlet chamber 29; having already been connected with a
suitable end use function, such as a oxygen connection,
welding torch or the like, has pressure build up to a value
determined by the degree of compression afforded by the
spring 17. As pressure increases in the low pressure chamber
2~, the pressure acting on the diaphram means 19 counter
balances the force of the spring 17 allowing the seat to be
engaged by the poppet again and block the flow of fluids.
During the opening and closing of the poppet with respect to
the seat, the normally destructive and noisy vibration that
is frequently otherwise induced is prevented through the co-
action of the centering extension 47 of the poppet 43 and
15 the centering protrusion 59 of the seat ~5. ~
Once the device employing the fluid from the outlet
begins to operate; as by taking oxygen by a welding torch7
oxygen mask, tent or the lîke; pressure decreases, unbalancing
the force opposing spring 17 which again depresses the
poppet 43, opening a flow passageway around the centeri.ng
protrusion 47 and through the slots 61. Flow of the fluid
continues until the pressure begins to build up to balance
the forces again. The flow of fluid may be greater or
lesser amounts. In every flow situation, the destructive
and noisy vibrations that are normally introduced in reg~llators
are prevented by this invention.
From the foregoing, it can be seen that this invention
achieves the objects set out hereinbefore.
Although this invention has been described with a
certain degree of particularity, it is understood that the
present disclosure is made only by way of e~ample and that
numerous changes in the details of construction and the
combination and arrangement of parts may be resorted to
without departing from the spirit and the scope of the
invention, reference being had for the latter purpose to the
appended claims.
