Note: Descriptions are shown in the official language in which they were submitted.
Docket Jo. DF-476
PRESSURE REGULATOR WIT FRICTION DAMPENER
SPECIFICATION
F id Of The Invention
This invention relates to pressure regulators.
More particularly, it relates to pressure regulators
such as are employed on manifolds or on cylinders of
5 compressed gases like oxygen in which a wettable lower
pressure is controlled by an adjustable spring
mechanism and in which the gas is throttled 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 manifolds or high pressure cylinders of
compressed gases such as oxygen to a low pressure of
only a few pounds per square inch (psi) as in hospital
15 oxygen systems, torches and the like. Basically these
regulators have consisted of a cartridge, including
either a movable poppet or seat and opposing seat or
poppet to control flow as necessary to attempt to
effect balanced forces between a heavy spring opposed
20 by a diaphragm to which low pressure is applied.
Patents such as US. 3,586,037 showed the ways of
compensating single stage pressure regulators to obtain
accurate regulation regardless of what the inlet pressure
was. Later filed patents such as 3,812,877 end its
25 divisional 3,906,982, described apparatus for overcoming
the significant friction that accompanied long
expanses of metal-to-metal contact in many of the prior
art regulators. Still later ones such as US. ~,257,450
show pressure regulators having a lost motion connection
30 so as to obtain reliable complete valve closure at
every shutoff regardless of whether or not there were
particles of
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carbon or the like adjacent the seat of the regulator.
One of the problems that has persisted in this field of
pressure regulators and has not been satisfactorily
solved is that of oscillation induced through resonance,
or vibration, caused by the high pressure gas flowing
past a valve seat or poppet as it nears its matins
poppet or seat. This vibration is very destructive to
the respective seat or poppet, particularly where one
its hard metal or the like. Moreover, it produces a
noisy vibration called "singing". In United States
Patent No. I, 471,802, by a co-worker David
A. Prior, entitled "PRESSURE REGULATOR ASSEMBLY WITH
IMPROVED CARTRIDGE", assigned to the assignee of this
invention, there was described an improvement employing
a movable poppet with a smaller diameter upper shaft
extension and a larger diameter lower shaft extension
cooperating with a biasing means to eliminate destructive
and noisy vibrations referred to as "singing" when gas
flow was needed. While that invention was very helpful
in alleviating some of the problems, it was not totally
satisfactory. It would be desirable to provide a
relatively soft seat to move into contact with a hard
ring poppet to be able to obtain larger variations in
volumetric rates of flow yet still affect positive
sealing and shut-off of the fluid.
Summary Of The Invention
Accordingly, it is an object of this invention to
provide a pressure regulator assembly having an improved
cartridge that eliminates the destructive and noisy
vibration between poppet and seat when throttling gas
flow; yet, that can handle large variations in the
volumetric rate of flow of the gas and still achieve a
positive shut-off when needed.
Specifically, it is an object of this invention to
provide high pressure regulator for reducing gas pressure
from a high pressure manifold or cylinder of the gas to a
low pressure end-use in which the poppet and seat are moved
apart to be opened when additional gas flow is required as
sensed by a regulator spring opposing a diaphragm subjected
5 to the low pressure and in which the poppet and seat can
be moved together to give a positive seal and closure when
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 in
conjunction with the appended drawings.
In accordance with this invention, there is provided an
improvement in a pressure regulator for reducing pressure
15 from high pressure to a low pressure in which the regulator
includes a valve body, seat and poppet, adjustable spring
and diaphragm member in the usual type regulator construction.
The improvement is characterized by having an improved
cartridge in which there is included a nozzle, a movable
20 seat including a centering extension shaft means extending
to the low pressure side of the plane of contact between the
movable seat and a ring poppet, the centering extension
shaft extending upwardly through an orifice in the superstructure
25 of the nozzle and the valve seat assembly being longitudinally
movable within a skirt defining a lower chamber in communication
with the inlet and high pressure chamber for moving the
valve seat in the form of a thermoplastic ring toward a ring
poppet in the form of a metallic ring defined by the nozzle.
30 The nozzle has fluid passageways extending radially and
angularly outwardly from a central passageway disposed
armularly about the centering extension shaft. The centering
extension shaft has a centering and dampening upper protrusion
that encompasses it and has a plurality
of slots defining a plurality of fingers for frictionally
dampening oscillations of the centering extension shaft. A
spring holds the seat assembly reciprocally movable within
the skirt of the nozzle. The centering and dampening upper
5 protrusion closely encompasses the centering extension
shaft and has its fingers defined with at least two slots
disposed substantially uniformly thereabout such that the
centering extension shaft is dampened and guided to obtain
oscillation-free flow. In a preferred embodiment there are
10 the two slots disposed diametrically opposite each other
or balance loading on the poppet although four, six, or
more can be employed and still operate.
Brief Description Of The Drawings
Fig. 1 is a partial cross-sectional view of the pressure
regulator in accordance with one embodiment of this invention.
Fig. 2 is a partial cross-sectional view of the improved
cartridge in accordance with another embodiment of this
invention.
Fig. 3 is a top plan view of the nozzle ox the embodiment
of Fig. 1.
Fig. 4 is a side elevation Al view of the nozzle of Fig.
3.
Fig. S is a cross-sectional view taken along the lines
5-5 of Fig. 3.
Fig. 6 is a top plan view of the centering and dampening
upper protrusion of Fig. 1.
Fig. 7 is a cross-sectional view taken along the lines
7-7 of jig. 6.
Fig. 8 is a partial cross sectional view of the improved
cartridge assembly of one embodiment of this invention
emplaced in a bottom portion of a valve body of a line, or
L-type, regulator.
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Fig. 9 is a partial cross-sectional view of the
improved cartridge assembly in a stationary, rear
entry, or S-type, regulator in accordance with another
embodiment of this invention.
Fig. 10 is a cross sectional view of one embodiment
of the seat assembly, including the centering extension
shaft and seat.
Fig. 11 is a plan view of the seat retaining ring
of lug. 10.
IT Fig. 12 is a side elevation Al, partly in section,
of the seat retaining ring of Fig. 11.
Description Of Preferred Embodiment(s)
In a low pressure regulator, such as employed in
this invention, the downstream pressure is usually
regulated to only a few psi and usually the upstream
pressure will not exceed about 350 psi maximum. With
proper design, however, it can be used on cylinders
of pressure up to 2,000-3,000 psi but high pressure
bodies are required for this type of regulation. It
is noteworthy that this regulation can also be employed
on vacuum regulation.
In Fig. 1 there is illustrated a cross-sectional
view of a regulator 11 in accordance with one embodiment
of this invention. The regulator 11 comprises the main
sub-assemblies of body 13, housing cap lo with its
adjustable spring 17, diaphragm means 19 and cartridge,
or core assembly, 21.
The body 13 has inlet passageway 23, inlet chamber
25, olltlet passageway 27 and outlet chamber 29. As
striated, 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.
Swiss recognized, such threads may be appropriately
right handed or left handed depending upon the nature
of the gas and to prevent inadvertently attaching the
so I
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regulator 11 to an incorrect cylinder of gas. For
example, regulators that are employed on inert gases
may have substances, such as oil or grease, that would
be incompatible with reactive gases, such as oxygen.
Coded threading is frequently employed to prevent
inadvertent wrongful attachment and is employed as
appropriate in the body of this regulator 13.
Inlet passageway 23 and the inlet 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 given by way of the
regulator cap 15 and its adjustable spring 17.
The regulator cap 15 is removably affixed to the
body 13, as by threaded connections, and has a compression
adjusting means illustrated by threaded stud 3] screwed
through tapped bushing 33 which is, in turn, fitted
into a receiving well in the cap 15, as by press
fitting or the like. It is noteworthy, however, that
it is unnecessary to have a press fitting, since the
bushing 33 is held in place by the upward reaction to
the downward pressure of the threaded stud 31 engaging
the spring button 34 pushing downwardly on the spring
17 The adjustable spring 17 has a bottom plate 35
contiguous the diaphragm means 17 and is adapted to
move therewith as pressure changes in the outlet
chamber 29. The spring 17 co-engages the button 34 at
its top and is responsive to the bottom of the threaded
stud 31. A handle 41 is provided for screwing the
threaded stud 31 to obtain a desired low pressure being
regulated. Specifically, rotation of the handle causes
rotation of the stud to increase or decrease the low
pressure that is regulated downstream of the regulator
11 .
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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 corrosive gases. The
usual type springs may be employed in this regulator and no
5 special alloys or springs are required.
The diaphragm lo 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 diaphragm will be
10 formed of a tough flexible material such as Neoprene or
other fluid impermeable material. The polyflourinated
hydrocarbons can be employed in accordance with conventional
technology in such instances. The diaphragms employed in
the prior art with the respective gases may be employed in
15 this invention and no special material or construction is
required.
The main improvement of this invention lies in the
improved cartridge 21 and its included movable seat 43 and
ring poppet 45, also as shown in Fig. 2. Specifically as
20 illustrated, the cartridge 21 includes a reciprocally
movable seat assembly 47 and a nozzle 49.
The seat assembly 47 is illustrated in more detail in
Fig. 10. It contains the seat 43 held in place by a seat
holder 51 interiorly of a retaining nut 53 and disposed
25 peripherally about a stem, or centering extension shaft,
55. As illustrated, the stem 55 is threadedly received in a
threaded aperture inside the seat holder 51 and protrudes
upwardly for engaging the diaphragm means 19 for being moved
responsive to changes in pressure. Since the downward
30 depression of the stem 55 causes downward depression of
the seat assembly 47, gas flows in turbulent flow about the
seat assembly 47
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and intermediate the seal 43 and the ring poppet 45.
As a consequence of this turbulent flow, the seat
assembly would tend to oscillate badly in the absence
of some restraining means. In fact, the oscillation is
so bad with a "singing" regulator thaw the regulators
can sometimes self-destruct. Consequently, there is
provided a centering and dampening means 57 about the
stem 55 near its upper end. The centering and dampening
upper protrusion means 57, Figs. 6 and 7, is provided
for centering and dampening the stem 55 The centering
and dampening means 57 comprises a body 59 that encompasses
the shaft 55 and has a plurality of fingers 61 that
extend in the illustrated embodiment from the body
toward the low pressure chamber 29 for frictionally
engaging the shaft 55. The fingers 61 are formed by a
plurality of slots 63 cut into the centering and
dampening means 57. There are as many slots as there
are fingers and the slots are preferably disposed
substantially uniformly about the centering and dampening
means. For example, only two slots may be formed, for
example, diametrically across the centering and dampening
means 57, as illustrated in Figs. 6 and 7. On the
other hand, four slots may be formed by completely
across at 90 with respect to each other. More slots can be
formed if desired but they are not necessary and represent
a waste of assembly time and money.
It is easier to mold the structure of the centering
and dampening means with one or two complete slots
forming respectively, two or four fingers. Consequently,
I these embodiments are preferred.
This type of structure is also advantageous in that
the respective fingers with the 'fears" on top allow
it to be snapped in place in the aperture in the nozzle,
and the fingers serve as a guide in combination with
the lower retaining nut holding the seat in the seat
assembly.
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If there is too great a friction or if the amount of
switches on the fingers is too great, the drag increases
pressure drop in the operation of the regulator. If, on the
other hand, there is too little drag, the fingers fail to
eliminate chatter, or oscillation of the movement between
the respective poppet and seat assembly portions.
In addition to the body and fingers illustrated in
jigs, 6 and 7, the centering and dampening means 57 also
includes an O-ring 65 that is slipped over the fingers and
10 is positioned intermediate the body 59 and the nozzle 49.
Specifically, as illustrated more clearly in Fig. 2, the
centering extension shaft 55 extends upwardly through an
aperture defined by the walls 69 of the superstructure of
the nozzle 49. The centering and dampening means can be
15 snapped into place in the aperture when the stem 55 is
not in place. Once the stem 55 is in place, however, the
centering and dampening means 57 is not extruded through the
aperture 69. The O-ring 59 has the desired effect of
causing clamping of the fingers 61 against the shaft 55 so
20 as to frictionally engage and dampen oscillations of the
valve seat assembly 49 by restricting and dampening out
longitudinal and lateral oscillations of the shaft 55.
The nozzle 49 is threadedly received in the body 13.
It has a chamber 71 defined by the interior of its skirt 73
25 for slide ably receiving the seat assembly 47. It contains
a central passageway 75 disposed annularly about the shaft,
or stem 55 and has a plurality of radially and angularly
outwardly extending passageways 77 for gas flow, such that
it is not necessary that the
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gas flow be through the centering and dampening means
57.
The reciprocally movable seat 47 is held upwardly
interiorly of the chamber 71 by spring 79. The sea
assembly 47 has splints 81, Figs. 2 and if, such as on
the exterior of the retaining nut 53, to fissility flow
of fluid therapist. As can be seen in Fig. 12, the
retaining nut 53 has threaded interior bore 83 for
receiving the seat holder 51 and holding the seat 43 it
place. The splints 81 define respective passageways
about the exterior of the seat assembly 47 and interiorly
of the chamber 71.
Engagement of the seat 43 and the seat assembly
with the ring poppet 45 of the nozzle 49 effects the
desired rate of flow or closure to stop flow. The
poppet 45 is formed of metal such as brass or the like,
as is the rest of the nozzle 49, Fig. 3. us can be
seen in Figs. 3-5, the nozzle 49 has a hexagonal, nut
shaped section to facilitate being screwed into and
from its conforming threaded bore in the boy 13. Its
chamber 71, passageways 75, 77 and aperture 69 are
illustrated. The aperture 69 has threaded shoulders
leading into and therefrom and shown by frusto-conical
and inverted frusto-conical sections I 89.
The usual materials and workmanship is employed in
this invention. For example, the respective poppets,
bushiTIgs, cartridge elements and the like may be formed
from brass, stainless steel or other metallic materials
appropriate to the type of gas being flowed therapist.
Where there is very little compressive and tensile
stresses, the thermoplastic materials can be employed.
Typically thermoplastic materials may be Nylon, Onion,
polyethylene, or the polyhalogenated hydrocarbon
materials. It is desirable, however, that the upwardly
extending centering extension shalt 55 have low friction
with respect to the centering and dampening means 57,
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but not too low. Consequently, some care should be taken in
selection of these materials. It has been found satisfactory
to employ brass shaft 55 and a molded thermoplastic material
for the friction damper, or centering and dampening means
5 57. While rlylon or other material can be employed, a
particularly satisfactory, relatively new material is an
improved Nylon impregnated with molybdenum disulfide,
corr~nercially available from The Polymer Corporation, Reading,
Pennsylvallia. It was chosen because it could be injection
10 molded more easily than Teflon, or other polyhalogenated
hydrocarbon materials. The 0-rings may be formed from
Neoprene or other conventional materials to give the desired
elastomeric character. The valve seat may be formed of any
Neoprene or any elastomeric material that is resistant to
15 corrosion and erosion by the gas being pressure regulated.
In operation, the low pressure regulator if is connected
with a high pressure cylinder of gas (not shown) by inlet
passageway 23 and appropriate conduit connection (also not
shown). With zero pressure set by compression adjusting
20 means in regulator cap 15, the pressure in high pressure
chamber 25, coupled with urging from spring 53, forces the
seat assembly upward to engage the seat 43 with the ring
poppet 45 and shut off flow of any gas.
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When the threaded stud 31 is screwed downward,
pressure is applied to spring 17 and force is transmitted
to unseat the seat it from the ring poppet I by force
of the diaphragm means 19, bottom plate 35 and centering
extension shaft 55. Outlet chamber 29; having already
been connected with a suitable index function, such as
cxvgen connection, welding torch or the live, 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 29, pressure
acting on the diaphragm means 19 counterbalances the
force of the spring 17 allowing the seat to be engaged
by the poppet again and block the flow of fluid.
During the normal opening and closing of the seat with
respect to poppet, the normal and destructive vibration
that is frequently otherwise induced is dampened out by
the centering and dampening means 57 frictionally
engaging the shaft 55.
Once the device employing the fluid from the
outlet begins to operate; as by taking oxygen by
welding torch, oxygen mass, tent or the like; pressure
decreases unbalancing the force opposing springs 17
which again depresses the seat assembly, opening flow
passageway between the poppet seat. Gases flow upwardly
through the chamber 71 and out the passageway 77 of the
nozzle 49. Flow of fluid continues until the pressure
begins to balance the forces again. The flow of fluid
may be greater or lesser amo~mts. In every flow
situation, the regulator of this invention substantially
I eliminates the destructive and noisy vibrations and
always alleviates problems that are normally introduced
in regulators regulating flow from high pressure into a
low pressure.
One of the advantages of this invention is that it
can be employed in substantially any type of regulator,
such as the AR-type regulators illustrated in Fig. 1,
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the line, or L-type regulators such as illustrated in
Fig. 8, or the stationary, or S-type regulators illustrated
in Fig. 9.
In the AR-type, air relieving, regulators that
S provide automatic bleed-off, the centering and dampening
means serve both to dampen and to keep the stem centered
so that the top of the stem shuts off against the
center aperture 91. Frequently, an O-ring is employed
in the center aperture to insure shut off. This
I requires a good alignment. The double guide alignment
in accordance with this invention ensures alignment
with the self relieving aperture in the center of the
AR diaphragm.
Referring to the other embodiments of this invention
and in particular to Fig. 8, the reference numerals
illustrate substantially the same sub-assemblies and
only a partial cross-sectional view is shown with the
bottom of the housing cap and body of the regulator are
shown. In the AR-type regulators illustrated in Fig.
1, the plate 35 has a center aperture 91 such that
pressure is relieved in the low pressure chamber 29
when the aperture 91 is backed off the top of the shaft
55. On the other hand, the top of the shaft 55 encounters
the aperture 91, flow is blocked and the pressure
operates normally. The advantage of this is that the
low pressure is relieved to atmosphere through passageways
93 in the housing cap 15. In the embodiment of Fig. 8,
although the passageway 93 are shown in the cap 15,
there is no center aperture so the pressure in the low
pressure chamber 29 remains trapped. In all the embodiments
of the regulators, an O-ring 95 seals about the nozzle
I when it is threaded into its receptacle.
The operation of the embodiment of Fig. 8 is
substantially the same as that described with respect
to Fig. 1 except for the air relieving bleed-off
through the central aperture 91.
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In the embodiment of Fig. 9, the same reference
numerals are employed to designate the same sub-assemblies
and elements as described herein before with respect to
Fig. 1. The major difference in the embodiment of Fig.
9 prom jig. 8 is that the entry passageway 23 is at the
bottom, or rear, of the regulator whereas Fig. 8 has
entry from the side, similarly as did Fig. 1. In Fig.
9, there is no central aperture 91, similarly as there
was not with respect to Fig. 8. Otherwise, the operation
Ox the embodiment of Fig. 9 is substantially the same
as the operation of the embodiment of Fig. 1.
In particular, this invention provides a frictional
dampening in combination with a nozzle and a seat
holder, the combination of the centering and upwardly
protruding shaft and the centering and dampening means
serving to prevent oscillations and dampen out noisy
and self-destructive vibrations. A particular combination
ox the movable fingers in combination with the O-ring
disposed about the body and bearing against the fingers,
creates just the right degree of drag and eliminate
chatter and instability without inducing high coefficient
of friction that would inhibit operation of the regulator.
Moreover, the centering and dampening means serves as a
guide, actually acting as a double guide in combination
with the aperture in the nozzle and the seat retaining
ring and the spring 79 pushing upwardly on the seat
assembly I
While the invention herein has been described and
illustrated with respect to a movable ring seat sealing
against a fixed ring poppet, the arrangement can be
reversed and the poppet moved, similarly as described
in United States Patent No. BYWAY.
prom the foregoing, it can be seen that this
invention achieves the objects set out herein before.
Although this invention has been described with a
certain degree ox particularity, it is understood that
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the present disclosure is made only by way of example
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.
