U.S. patent application number 13/119593 was filed with the patent office on 2011-07-21 for fluid regulator.
Invention is credited to Soeren Kristoffersen.
Application Number | 20110175009 13/119593 |
Document ID | / |
Family ID | 41136910 |
Filed Date | 2011-07-21 |
United States Patent
Application |
20110175009 |
Kind Code |
A1 |
Kristoffersen; Soeren |
July 21, 2011 |
FLUID REGULATOR
Abstract
A fluid pressure regulating unit (1, 28, 35, 56, 58), comprises
a fluid inlet port (3), a fluid outlet port (4), a valve means (6)
and a main valve biasing means (14, 36). The main valve biasing
means (14) biases said valve means (6) in the direction of an open
position. An auxiliary valve biasing means (26) is provided,
biasing the valve means (6) in the direction of a closed
position.
Inventors: |
Kristoffersen; Soeren;
(Hadsund, DK) |
Family ID: |
41136910 |
Appl. No.: |
13/119593 |
Filed: |
September 17, 2009 |
PCT Filed: |
September 17, 2009 |
PCT NO: |
PCT/DK09/00208 |
371 Date: |
March 28, 2011 |
Current U.S.
Class: |
251/321 |
Current CPC
Class: |
Y10T 137/7835 20150401;
F16K 15/063 20130101; F16K 31/1223 20130101; F16K 17/06 20130101;
F16K 1/307 20130101; F16K 17/044 20130101; F16K 31/1226 20130101;
G05D 16/103 20130101; Y10T 137/7762 20150401; Y10T 137/7836
20150401; F16K 31/1221 20130101; Y10T 137/7905 20150401 |
Class at
Publication: |
251/321 |
International
Class: |
F16K 1/00 20060101
F16K001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 19, 2008 |
EP |
08016555.8 |
Claims
1. A fluid pressure regulating unit, comprising a fluid inlet port,
a fluid outlet port, a valve means and a main valve biasing means,
wherein said main valve biasing means biases said valve means in
the direction of a first position, comprising an auxiliary valve
biasing means, wherein said auxiliary valve biasing means biases
said valve means in the direction of a second position, being
different from said first position.
2. The fluid pressure regulating unit as claimed in claim 1,
wherein said first position and said second position are opposing
each other, in particular that said first position corresponds to
an open position and said second position corresponds to a closed
position of said valve means.
3. The fluid pressure regulating unit as claimed in claim 1,
wherein said main valve biasing means and/or said auxiliary valve
biasing means comprises a fluid pressure operated member and/or an
elastically deformable member, in particular a spring, preferably a
metal spring and/or a helically wound spring.
4. The fluid pressure regulating unit as claimed in claim 1,
wherein at least one of said valve biasing means, in particular
said main valve biasing means is adjustable.
5. The fluid pressure regulating unit as claimed in claim 1,
wherein said valve member comprises a variable fluid flow cross
section.
6. The fluid pressure regulating unit as claimed in claim 1 wherein
said valve member comprises an axially movable tubular unit,
wherein preferably said tubular unit comprises an inner
passage.
7. The fluid pressure regulating unit as claimed in claim 1,
wherein said valve member comprises a valve seat with an
essentially even surface, in particular a plate-like valve
seat.
8. The fluid pressure regulating unit as claimed in claim 1,
wherein the position of said valve means is essentially independent
of the fluid pressure in said fluid inlet port and/or the position
of said valve means is at least partially dependent on the fluid
pressure in said fluid outlet port.
9. The fluid pressure regulating unit as claimed in claim 1,
comprising at least one fluid inlet side pressure balancing
means.
10. The fluid pressure regulating unit as claimed in claim 1,
wherein essentially every surface part, being fluidly connected to
said fluid inlet port and having a surface normal at least
partially in parallel to the moving direction (A) of the moving
part of said valve means, is balanced by a balancing surface
part.
11. The fluid pressure regulating unit as claimed in claim 1,
wherein said valve member, in particular said axially movable
tubular unit is designed and arranged with a minimum of surface
parts, being fluidly connected to said fluid inlet port and having
a surface normal at least partially in parallel to the moving
direction (A) of the moving part of said valve means, in particular
in that said axially movable tubular unit comprises a tapered
surface part.
12. The fluid pressure regulating unit as claimed in claim 1,
wherein said valve means is in said second position, in particular
in a closed position, if said main valve biasing means is in a
weakly biased and/or unbiased state.
13. The fluid pressure regulating unit as claimed in claim 1,
comprising at least one actuator means.
14. The fluid pressure regulating unit as claimed in claim 13,
wherein pilot pressure applying means are provided, which
preferably can be selectively connected to said first fluid port
and/or said second fluid port.
15. The fluid pressure regulating unit as claimed in claim 14,
wherein said pilot pressure applying means can be connected to a
respective fluid pressure reservoir via a fluid throughput reducing
means.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is entitled to the benefit of and
incorporates by reference essential subject matter disclosed in
International Patent Application No. PCT/DK2009/000208 filed on
Sep. 17, 2009 and European Patent Application No. 08016555.8 filed
on Sep. 19, 2008.
FIELD OF THE INVENTION
[0002] The invention relates to a fluid pressure regulating unit,
comprising a fluid inlet port, a fluid outlet port, a valve means
and a main valve biasing means, wherein said main valve biasing
means biases said valve means in the direction of a first
position.
BACKGROUND OF THE INVENTION
[0003] Fluid regulators as such are well known in the state of the
art. They are used to reduce the pressure of a fluid, entering the
fluid regulator on a high pressure side, to a lower pressure level
on the fluid outlet side. Preferably, the pressure on the fluid
outlet side will be essentially constant. Such pressure regulating
units are used, for example, for pressurized gas bottles (pressure
cylinders), where the pressure of the gas inside the bottle of up
to 300 bars (or even higher) has to be reduced to a lower pressure
level of usually 3-10 bars, which can be handled better. In some
applications, however, a reduced pressure on a level around 40-50
bars is desired. However, other lower pressures are also possible,
like pressures in the area of 20 bars, 30 bars, 60 bars, 70 bars,
80 bars, 90 bars, 100 bars, 110 bars, 120 bars, 130 bars, 140 bars,
150 bars, 160 bars, 170 bars, 180 bars, 190 bars or 200 bars, to
give some examples. Another example for the use of fluid regulators
are fire extinguishers and/or fire extinguishing systems (fire
fighting systems), which can be portable, mobile (built into a
vehicle, for example) or stationary (built into a building, for
example). Here, the supply of a fire extinguishing agent with a
usually changing pressure level during use has to be reduced to
lower pressure level with a preferably constant pressure. The fire
extinguishing agent with the reduced pressure level can hence be
expelled by an appropriate nozzle, for example.
[0004] For the fluid, not only gases are possible. Also, liquids
(like liquid CO.sub.2, for example), supercritical fluids (where no
distinction between the liquid and the gaseous phase is possible
any more), and mixtures of liquids, supercritical fluids and/or
gases are possible. Also, the fluid can even contain a certain
percentage of solids (smoke and/or suspensions, for example).
[0005] The problem with the majority of presently existing pressure
regulators is the usually high number of movable parts, necessary
for the construction of the pressure regulator. Apart from the
costs involved with manufacturing and arranging a large number of
movable parts, this also gives rise to vibration problems. Such
vibrations can lead to the generation of noise and a bad output
pressure characteristics (i.e. randomly varying output pressure).
Another problem is that in the majority of presently available
pressure reducers, the fluid, which pressure has to be reduced, has
to change its moving direction several times, when flowing through
the pressure regulator. This can give rise to a slow pressure
regulation response and therefore to a bad pressure output
characteristics. The output characteristics of such a pressure
regulator is usually particularly bad, if the fluid input reservoir
becomes exhausted and the fluid inlet pressure is getting close to
the fluid outlet pressure of the pressure regulator.
[0006] For improving the pressure output characteristics and
reducing the vibration problems, so called "in-line" constructions
have been proposed. In these "in-line" constructions, the number of
directional changes of the fluid flowing through the pressure
regulator is reduced. Furthermore, the number of moving parts can
usually be reduced with in-line constructions. Therefore, in-line
pressure regulators usually show less vibrations and a more
constant, less fluctuating fluid output pressure.
[0007] Examples of pressure regulators, using the "in-line" design
can be found in U.S. Pat. No. 2,777,458 and U.S. Pat. No.
3,890,999, for example. However, presently existing designs of
in-line pressure regulators still suffer from a number of
drawbacks. A major drawback, for example, lies in mounting the
pressure regulator for the first time after delivery and in the
delivery state of the pressure regulator itself. The problem lies
in particular in that the pressure regulator usually is in an open
state, when delivered from the manufacturer. This, however, can
lead to the release of a too high pressure after mounting the
pressure regulator. Furthermore, the pressure regulator can suffer
damages during shipment, particularly if the valve of the fluid
pressure regulator is shipped in an open position. Also, there are
situations, in which it is desired that the pressure regulator can
be cut off. With presently available fluid pressure regulators,
usually a separate cut-off valve is needed for this.
SUMMARY OF THE INVENTION
[0008] The object of the present invention lies therefore in
providing an improved fluid pressure regulating unit, as compared
to fluid pressure regulating units according to the state of the
art.
[0009] It is suggested to provide a fluid pressure regulating unit,
comprising a fluid inlet port, a fluid outlet port, a valve means
and a main valve biasing means, wherein said main valve biasing
means biases said valve means in the direction of a first position,
with an auxiliary valve biasing means, wherein said auxiliary valve
biasing means biases said valve means in the direction of a second
position, being different from said first position. Using such an
auxiliary valve biasing means, it is possible to reliably close the
fluid pressure regulating unit, without the need for a separate
fluid cut-off valve. This is of particular advantage, because it is
quite often required to reliably cut off the fluid connection. This
not only occurs during an initial setup of an arrangement, using a
fluid pressure regulating unit, but also during the operation of
such an arrangement. Usually, the auxiliary valve biasing means is
designed to be relatively weak and/or small as compared to the main
valve biasing means. Therefore, the main valve biasing means can
usually easily counteract the forces, imposed by the auxiliary
valve biasing means, if properly set. It has to be noted that
according to usual designs of pressure regulators, a main valve
biasing means is already present. Additionally, in usual setups,
the main valve biasing means is already designed to have a
relatively high strength. Hence, when using presently available
main valve biasing means, the forces, imposed by said auxiliary
valve biasing means can usually be easily compensated for, e.g. by
a slightly higher tensioning of the main valve biasing means. Of
course, the auxiliary valve biasing means should be able to provide
a force, being sufficient to securely close the valve means of the
fluid pressure regulating unit. In the context of the present
application, by the notion fluid, liquids, gases, mixtures of
fluids and gases and supercritical fluids are in encompassed. It is
even possible, that a fluid can contain a certain amount of solid
particles (e.g. smoke and/or suspensions).
[0010] Preferably, the fluid pressure regulating unit is designed
in a way that said first position and said second position are
opposing each other, in particular in that said first position
corresponds to an open position and said second position
corresponds to a closed position of said valve means. Using such an
arrangement, the main valve biasing means can easily and
effectively compensate for the forces, generated by the auxiliary
valve biasing means. In particular, frictional losses or the like
can be minimized. If said first position corresponds to an open
position and said second position corresponds to a closed position
of said valve means, the main valve biasing means usually performs
an opening of the pressure regulating unit, while the auxiliary
valve biasing means performs the closing of the pressure regulating
unit. Of course, in usual setups of pressure regulating units the
closing movement of the valve means is also performed by the
influence of the fluid pressure on the fluid outlet side of the
fluid pressure regulating unit. With the proposed arrangement,
already existing fluid pressure regulating units can easily be
adapted according to the presently suggested design. Therefore,
costs can be reduced and it is even possible to provide a drop-in
solution.
[0011] Another possible embodiment can be achieved, if said main
valve biasing means and/or said auxiliary valve biasing means
comprises the fluid pressure operated member and/or an elastically
deformable member. The elastically deformable member can be in
particular a spring, preferably a metal spring and/or helically
wound spring. Such devices are readily available, so that the
proposed fluid pressure regulating unit can be manufactured easily,
cheaply and in high numbers. A fluid pressure operated member can
be of an active and/or a passive type. An active fluid pressure
operated member can be realized by providing fluid chambers, which
can be fluidly connected to external fluid reservoirs (pressurized
and/or unpressurized). Using such an active fluid pressure operated
member, an actively controllable fluid pressure regulating unit can
be provided. A passive fluid pressure operated member can be
realized by providing closed chambers, filled with a gas. This way,
a gas spring strut like member can be provided. An elastically
deformable member can be essentially made of any elastically
deformable material, for example out of rubber and the like.
Preferably a spring (e.g. made of metal) can be provided. Although
every form of spring can be used, normally a helical spring shows
the best results.
[0012] It is preferred, if at least one of said valve biasing
means, in particular said main valve biasing means is adjustable.
This way, the fluid pressure regulating unit can be easily adjusted
to the intended use. In particular, the fluid pressure regulating
unit can be changed from an initial delivery adjustment, as set by
the manufacturer, to an adjustment, needed for the setup, the fluid
pressure regulating unit is used for. Normally, the fluid
regulating unit is designed in a way that the valve biasing means
can be readjusted, e.g. during operation of the unit, when the unit
is transferred to a different application and/or when the fluid
pressure regulating unit is taken out of the unit and put into
another unit.
[0013] Preferably, said valve member of said fluid pressure
regulating unit comprises a variable fluid flow cross section. This
way, an adaptable fluid flux through the fluid pressure regulating
unit can be provided. Depending on the fluid outlet flux on the
fluid outlet side of the fluid pressure regulating unit, a
different fluid flux through the valve means is necessary to
sustain a certain pressure level on the fluid outlet side of the
fluid pressure regulating unit.
[0014] A preferred arrangement is achieved, if said valve member
comprises an axially movable tubular unit, wherein preferably said
tubular unit comprises an inner passage. Using such an arrangement,
usually a very simple setup of the fluid pressure regulating unit
can be achieved. In particular, the opening of said axially movable
tubular unit on one side can be used as a part of the valve seat
arrangement, where the variable fluid flow-cross section of the
valve member is located. Using a tubular unit, normally relatively
huge changes in fluid flow cross section can be achieved with a
relatively small axial movement of the tubular unit. The tubular
unit can comprise one or several extensions, in particular radial
extensions, which can be used as a fluid pressure receiving surface
(in particular of the fluid pressure on the fluid outlet side of
the fluid pressure regulating unit) and/or as a web for mounting a
mechanical spring, for example. These effects can be particularly
well achieved, if the axially movable tubular unit comprises an
inner passage. This inner passage can be used for the fluid, being
regulated by fluid pressure regulating unit.
[0015] It is possible to design the pressure regulating unit in a
way that said valve member comprises a valve seat with an
essentially even surface, in particular a plate like valve seat.
Such a valve seat can be easily and cheaply manufactured.
Furthermore, leakage due to imperfections of the valve seat and/or
the corresponding valve member can be reduced, because the
respective surfaces can be easily and precisely manufactured. Also,
unwanted pressure drops, being caused by the valve member, can be
reduced, since a relatively large fluid flow cross section can be
provided (in particular, if the valve member is arranged in a
rotationally symmetric manner) and because the necessary
redirection of the fluid, flowing through the fluid pressure
regulating unit is relatively small. Also, the valve seat can be
designed to be changeable. This way, a fluid pressure regulating
unit with a very long lifetime can be provided.
[0016] Usually, the fluid pressure regulating unit should be
designed in a way that at least one valve biasing means is at least
partially in mechanical contact with said tubular unit. This can be
achieved, for example, by a direct contact between a mechanical
spring and a web of the tubular unit. This way, vibrations due to a
play between the valve biasing means and the tubular unit can be
reduced. If the (one or several) valve biasing means is in a
relatively direct contact with said tubular unit, the pressure
output characteristics of the fluid pressure regulating unit can be
even further improved.
[0017] A preferred embodiment of the fluid pressure regulating unit
is achieved, if the position of said valve means is essentially
independent of the fluid pressure in said fluid inlet port and/or
the position of said valve means is at least partially dependent on
the fluid pressure in said fluid outlet port. This way, the desired
output pressure characteristics of a pressure regulator can be
provided. In fact, the usually desired pressure output
characteristics of a pressure regulator is that the fluid output
pressure is constant, independent of the fluid inlet pressure.
However, sometimes a slight dependence on the fluid inlet pressure
is also desired, because the operator can be provided with a
feedback on the amount of still available fluid on the high
pressure side of the apparatus, for example.
[0018] Preferably, the fluid pressure regulating unit is provided
with at least one fluid inlet side pressure balancing means. By a
fluid inlet side pressure balancing means, any device is in
encompassed, which at least essentially provides for a fluid output
pressure, being essentially independent of the fluid inlet
pressure. For achieving this, every balancing means, known in the
state of the art, can be used.
[0019] Preferably essentially every surface part, being fluidly
connected to said fluid inlet port and having a surface normal at
least partially in parallel to the moving direction of the moving
part of said valve means, is balanced by a balancing surface part.
In other words, every surface which yields a (vectorial fractional)
force in the direction of the movement of the moving part of the
valve means, when being exposed to a pressure, being applied
through the fluid inlet port of the fluid pressure regulating unit,
has an "opposing" surface part. The "opposing" surface part is
arranged in a way that a (vectorial fractional) second force is
generated, when pressure is applied to the fluid inlet port of the
fluid pressure regulating unit. The two forces are preferably of
the same magnitude and of opposite directions. Therefore, the
occurring forces can cancel each other and the resulting net force
can be zero. In other words, the valve means can be independent of
the pressure on the fluid inlet side of the fluid pressure
regulating unit.
[0020] Additionally and/or alternatively it is also possible that
said valve member, in particular said axially movable tubular unit
is designed and arranged with a minimum of surface parts, being
fluidly connected to said fluid inlet port and having a surface
normal at least partially in parallel to the moving direction of
the moving part of said valve means. In particular, said axially
movable tubular unit can comprise a tapered surface part. Using
such a design, the above described balancing of surface parts can
be at least in part avoided. It is to be noted that for example
radial surface parts of the movable tubular unit do not yield a
(net) force, pointing in the direction of movement of the movable
tubular unit. In particular, if no balancing is necessary, fluid
flow delays resulting in small, time dependent pressure variations
on balancing surface parts can be avoided, yielding an improved
behaviour of the fluid pressure regulating unit. The tapered
surface part of the movable tubular unit can be particularly
arranged on the side, being fluidly connected with the fluid outlet
port of the fluid pressure regulating unit. Using tapered surface
parts, in particular a highly leak-proof valve seat can be provided
for.
[0021] Preferably, the adjustment of at least one of said valve
biasing means is performed using a biasing thread. With a biasing
thread, a relatively large movement (e.g. by the operator of the
machinery) can be translated into a small movement of the
respective biasing means. Thus, the fluid pressure regulating unit
can be precisely adjustable. Also, threads are usually self
locking.
[0022] A preferred embodiment can be achieved, if said valve means
is in said second position, in particular in a closed position, if
that main valve biasing means is in a weakly biased and/or unbiased
state. Thus, by loosening the main valve biasing means, a positive
closing of the fluid pressure regulating unit can be easily
performed by the auxiliary valve biasing means.
[0023] Preferably, the fluid pressure regulating unit is designed
and arranged as an in-line regulator unit. Using such a design, the
number and amount of redirections of the fluid, flowing through the
fluid pressure regulating unit can be minimized, thus yielding an
improved pressure output characteristic of the fluid pressure
regulating unit. Furthermore, using an in-line design, the
resulting vibrations can usually be reduced.
[0024] Preferably, said fluid pressure regulating unit comprises at
least one actuator means. This way, it is possible to close the
fluid pressure regulating unit positively by applying an external
signal, for example. This closing of the fluid pressure regulating
unit can be performed independent of the fluid pressure at the
fluid output port. This way, the functionality of an actuated
cut-off valve can be easily incorporated into the fluid pressure
regulating unit.
[0025] It is possible to design said fluid pressure regulating unit
in a way that pilot pressure applying means are provided, which
preferably can be selectively connected to said first fluid port
and/or said second fluid port. This way, the actuator of the
resulting unit can be switched, using fluid pressures. In
particular it is even possible to change the state of fluid
pressure regulating by the pressures, occurring in the fluid to be
influenced by the fluid pressure regulating unit. Of course, it is
possible to perform a switching of the pilot pressure actuated
fluid pressure regulating, using a different switching means. The
switching means can be based on the fluid pressure, mechanical
forces, electricity, magnetic forces and the like, for example.
[0026] Another embodiment of said fluid pressure regulating unit
can be achieved, if said pilot pressure applying means can be
connected to a respective fluid pressure reservoir via a fluid
throughput reducing means. Such a fluid throughput reducing means
can be a throttle or an orifice opening, for example. Using such a
device, the "consumption" of the actuating fluid can be
advantageously decreased. Furthermore, it possible to provide for a
"soft" changeover between different states of the valve unit, which
can result in decreased wear of the fluid pressure regulating
unit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The present invention and its advantages will become more
apparent, when looking at the following description of possible
embodiments of the invention, which will be described with
reference to the accompanying figures, which are showing:
[0028] FIG. 1: is a first embodiment of a pressure regulator with
an auxiliary spring;
[0029] FIG. 2: is a second embodiment of a pressure regulator with
an auxiliary spring;
[0030] FIG. 3: is a third embodiment of a pressure regulator with
an auxiliary spring;
[0031] FIG. 4: is a third embodiment of a fluid pressure regulator;
and
[0032] FIG. 5: is a fourth embodiment of a fluid pressure
regulator.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] In FIG. 1, a schematical cross section through a first
possible embodiment of a pressure regulator 1 is depicted. The
pressure regulator 1 comprises a casing 2 with a fluid inlet port 3
and a fluid outlet port 4. Both fluid inlet port 3 and fluid outlet
port 4 have an inner thread 5, so that a corresponding fluid pipe
or fluid hose can be threadingly engaged in the respective fluid
port 3, 4.
[0034] Within the casing 2 of the pressure regulator 1, a valve
unit 6 is arranged. The valve unit 6 essentially consists of a
valve seat 7 and a valve tube 8. The valve tube 8 can be moved in
an axial direction (as indicated by double-headed arrow A) within
the casing 2 of the pressure regulator 1.
[0035] The valve tube 8 is designed to have a hollow interior 9,
forming an inner fluid line 9 through the valve tube 8. The
contacting area between valve seat 7 and valve tube 8 forms the
valve opening 10. If the valve tube 8 is in its leftmost position
(as drawn in FIG. 1), the valve seat 7 and the contacting edge 11
of the valve tube 8 contact each other, thus closing the valve
opening 10. In this position, no fluid flow is permitted between
fluid inlet port 3 and fluid outlet port 4. When the valve tube 8
is moving to the right, however, the contacting edge 11 of the
valve tube 8 and the valve seat 7 get out of contact from each
other, thus opening the valve opening 10. Hence, fluid can flow
from the fluid inlet port 3 to the fluid outlet port 4.
[0036] In the embodiment of the pressure regulator 1, shown in FIG.
1, the valve seat 7 is designed as a flat, circular plate. The
valve seat 7 is held in place by several holding bars 12. Between
the holding bars 12, openings are provided, so that fluid can pass
through. Corresponding to the design of the valve seat 7, the valve
tube 8 is designed to have a circular cross section. Consequently,
the contacting edge 11 shows a circular cross section. In the area
close to the valve opening 10, the valve tube 8 comprises tapered
edges 13 on the inner side 9 of the valve tube 8, thus forming
sharp contacting edges 11. The valve seat 7 is made of a slightly
deformable material, so that the contacting edges 11 can slightly
indentate the valve seat 7, thus forming a tight fluid seal.
[0037] In a normal working adjustment position (main spring 14
biased), the valve tube 8 is pushed out of contact with the valve
seat 7 (thus opening the valve opening 10) by means of the main
spring 14. The main spring 14 is supported on its right side (see
FIG. 1) by a circular web 15 integrally formed with the valve tube
8. On the left side, the main spring 14 is supported by a nut 16.
The nut 16 shows an inner thread 17, which is engaged to a
corresponding thread, arranged on the outer side of a collar like
extension 23 of the casing 2. By a turning action of the nut 16,
the nut 16 can be displaced in an axial direction A by means of the
thread 17. Therefore, the biasing force of main spring 14 can be
adjusted to the appropriate amount. For ease of manipulation, the
nut 16 is designed to have a plurality of openings 22 for insertion
of a part of an appropriate tool. Also, the casing 2 of the
pressure regulator 1 is designed with an access window 24 for easy
manipulation of the nut 16. Hence, the second interior space 19
within the casing 2 of pressure regulator 1 shows ambient pressure.
Therefore, sealing rings 21 are provided between first internal
space 18, second internal space 19 and third internal space 20,
respectively.
[0038] The working cycle of the pressure regulator 1 is as
follows:
[0039] Initially, the valve tube 8 is in its open position (right
side in FIG. 1; valve opening 10 is open). Fluid at high pressure
enters the fluid inlet port 3 of the pressure regulator 1. The
fluid flows through the first internal space 18, past the opened
valve opening 10, through the inner fluid line 9 of valve tube 8
into the third internal space 20. According to an actual fluid flow
demand, part of the fluid entering third internal space 20 leaves
the casing 2 of the pressure regulator 1 by fluid outlet port 4.
However, in an open position of the valve unit 6, a positive net
fluid flow into the third internal space 20 occurs. Therefore,
pressure builds up in the third internal space 20. With increasing
pressure, an increasing force is exerted on the piston surface 25
of the valve tube 8. At some point, the net force, pushing the
valve tube to the left exceeds the net force, pushing the valve
tube 8 to the right. Thus, the valve opening 10 closes and the
pressure within the third internal space 20 remains at its set
level. If the pressure inside the third internal space 20 drops
again due to fluid, leaving through fluid outlet port 4, the valve
tube 8 will move slightly to the right, thus opening the valve
opening 10 slightly. Hence, an equilibrium is achieved, so that the
pressure in the third internal space 20 remains constant.
[0040] Apart from the pressure, exerted by the fluid within third
internal space 20 onto the piston surface 25 of valve tube 8, an
additional force is exerted by means of an auxiliary spring 26. The
auxiliary spring 26 has a small spring constant, when compared to
the spring constant of main spring 14. Thus, in a normal adjustment
position of pressure regulator 1, the main spring 14 may easily
compensate for the pressure, exerted by auxiliary spring 26.
However, if the nut 16 is adjusted in a way that main spring 14 is
(essentially) in an unbiased state, the force, exerted by auxiliary
spring 26 is sufficient to safely close the valve unit 6 of the
pressure regulator 1. Therefore, no additional valve is needed,
although the functionality of a cut-off valve is implemented in the
pressure regulator 1.
[0041] The closed position of the pressure regulator 1 (main spring
14 unbiased), is also advantageous for shipping the pressure
regulator 1. In particular, normal vibrations during transportation
of the pressure regulator 1 will not be able to open and close the
valve unit 6 repetitively. Thus, a wear of the pressure regulator 1
during transportation can be avoided.
[0042] Also, the auxiliary spring 26 can provide for an unambiguous
position of the tube 8. Therefore, one always know in which
position the system will start and/or the system was arranged.
[0043] Another feature of the pressure regulator 1, shown in FIG.
1, is that the axially movable valve tube 8 shows no surface parts
within the first internal space 18 (high pressure chamber), which
have to be balanced. If a fluid pressure is present in first
internal space 18, every surface of the valve tube 8, being in
contact with the high pressure fluid in first internal space 18
shows a surface normal, being solely perpendicular to the moving
direction of the valve tube 8. Therefore, any pressure within first
internal space 18 will neither generate force, urging the valve
tube 8 in an open position, nor generate a force, urging the valve
tube 8 in a closing direction. Therefore, the high pressure part of
pressure regulator 1 is perfectly balanced, even without balancing
surfaces.
[0044] On the inner side of the valve tube 8 in the vicinity of the
valve opening 10, the movable valve tube 8 shows a tapered surface
13, creating a sharp edge 11. This way, fluid resistance is
reduced, if the valve opening 10 is open. Also, a tight seal can be
provided if the valve opening 10 is closed. It has to be noted that
the tapered part 13 of the valve tube 8 is additionally working as
a balancing surface for the respective surface part of the piston
surface 25 of the valve tube 8 (both fluidly connected to the fluid
outlet port 4). However, in the presently depicted embodiment of
FIG. 1, the pressure regulator 1 is still dependent on the fluid
outlet pressure, because a flange part 27 is provided for the valve
tube 8, showing a cross section, exceeding the cross section of
tapered surface parts 13.
[0045] The special design of the tapered surface 13 on the inner
side 9 of the valve tube 8 in the vicinity of the valve opening 10
insures that the pressure drop of the fluid, flowing through the
pressure regulator 1 will essentially occur in a very small area.
Therefore, this construction can be less effected by variations in
the pressure within first internal space 18. This is, because the
areas, being in contact with the high pressure fluid are extremely
small as compared to the areas, being in contact with the low
pressure fluid. The auxiliary spring 26 can put the pressure
regulator 1 in a shut off state, if there is no load on the main
spring 14 (or on the flange part 38 of valve tube 8 in the pressure
regulator 35, as shown in FIG. 3). Hence, the fluid regulator 1
described can work as a shut off valve as well.
[0046] Of course, it is also possible to design the flange part 27
in a different way, as long as the described functionality of the
flange part 27 is provided. For example, the flange part 27 could
be designed as a membrane for the like. Of course, such an
alternative design could be used in units of a different design as
well.
[0047] In FIG. 2, a second possible embodiment of a pressure
regular 28 is shown. Most parts of the present pressure regulator
28 are similar or the same as those used for pressure regulator 1,
as illustrated in FIG. 1.
[0048] As described in connection with pressure regulator 1, the
presently used valve tube 32 comprises a tapered surface 30 in the
vicinity of the valve seat 7. The tapered surface 30, however, is
presently arranged on the outside of the valve tube 32, thus facing
towards the first internal space 18, being fluidly connected to the
fluid inlet port 3 of pressure regulator 28. This, however,
introduces a force, urging the valve tube 32 into an opening
direction, when high pressure is applied to the first internal
space 18. The effective opening force is the vectorial fraction of
the pressure force, pointing in the direction of movement of valve
tube 32. To balance for this force, the pressure regulator 28 is
provided with a balancing section 33. Within the balancing section
33, the fourth internal space 29 is provided, which is fluidly
connected to the first internal space 18 by a fluid channel 34.
Facing towards the fourth internal space 29, the valve tube 32 is
provided with a balancing web 31. The size of the balancing web 31
is chosen in a way that the resulting force, being exerted onto the
valve tube 32 when pressure is applied to fluid inlet port 3 (and
therefore to first internal space 18 and fourth internal space 29)
is of the same magnitude as the force generated by the tapered
surface 30. The direction of both forces, however, is opposite to
each other. Therefore, both forces cancel each other. Thus, the
pressure regulator 28 is balanced towards the high pressure side.
In other words, the output pressure characteristics of the pressure
regulator 28 is independent of the pressure at fluid inlet port
3.
[0049] An advantage of the proposed design with the tapered surface
30 on the outside of the valve tube 32 is that the dimensions of
the fluid tube 32 can be chosen from a very wide range. This is,
because generally speaking an almost arbitrary size of the surface
area on the front side of the valve tube 32 (near valve opening 10)
can be compensated by the counteracting force delivered by the ring
like web 31 of valve tube 32. Thus, a pressure regulator 28 of the
design proposed can be used with very high pressures.
[0050] As an example, the thickness of the walls of the valve tube
8, 32 is normally in the order of one millimetre (pressures in the
range from 200 to 300 bars). However, with the proposed design,
wall thicknesses for the valve tube 8, 32 in the area of several
millimetres can be easily realized.
[0051] Of course, the design of the pressure regulator 28, as shown
in FIG. 2, can be used for the design of a pilot driven valve 41,
53 as well (see FIGS. 4, 5). In particular, the arrangement of the
tapered surface 30 on the outside of valve tube 32 can be used for
pilot driven valves 41, 53. Of course, the tapered surface 30 on
the outside of the valve tube 32 can also be used in connection
with the pilot driven 37 fluid pressure regulator 35 design, as
depicted in FIG. 3.
[0052] In FIG. 3 another possible embodiment of a pressure
regulator 35 is illustrated. Here, the main spring 14 is omitted.
As a replacement for the main spring 14, a pilot pressure chamber
36 is provided. The pilot pressure chamber 36 is fluidly connected
to a pilot fluid port 37. On one side of the pilot pressure chamber
36, a flange part 38 of the valve tube 39 is located. Therefore, by
applying a pressure to the pilot pressure chamber 36, an
appropriate biasing force can be exerted on the valve tube 39. The
biasing can be changed by varying the pressure, applied to the
pilot pressure chamber 36. It has to be noted that this way an
automated change of biasing force can be easily implemented. For
optimum performance, the medium in the pressure chamber 36 should
be compressible. For example, a gas or a liquid/gas mixture with a
certain gas contents could be used. However, even a
non-compressible fluid could be used. Particularly in that case,
however, some compressible device should be used, like a
compressible gas-filled sphere or a kind of spring operated
storage, which can be loaded by a pressure pulse in the biasing
fluid. The backside volume 40 is of course at ambient pressure.
[0053] Apart from this, the pressure regulator 35, as depicted in
FIG. 3, resembles the pressure regulator 1, as shown in FIG. 1.
[0054] In FIG. 4, a pilot controlled fluid pressure regulator 56 is
depicted. The pilot controlled fluid pressure regulator 56 can be
considered to be a fluid pressure regulator 1, as shown in FIG. 1,
in which a pilot control section 59, comprising an additional
closing chamber 57 is provided. The closing chamber 57 is fluidly
connected to the first internal space 18 via a feeding line 48 and
a connecting line 47. The fluid flux through the feeding line 48 is
limited by a throttle 51, which can be formed as a part of the
feeding line 48. If the piloting valve 50 is in its closed position
(as shown in FIG. 4), the pressure in the closing chamber 57 will
eventually be the same as the pressure in the first internal space
18. Therefore, the pressure of the fluid in closing chamber 57
exerts a force on the flange part 38 of valve tube 8. This will
cause the valve tube 8 to move to the left side, i.e. pushing the
valve tube 8 on the valve seat 7, thus closing the valve unit 6.
Therefore, the pilot controlled fluid pressure regulator 56 can be
safely closed, irrespective of the fluid pressure in third internal
space 20, i.e. irrespective of the fluid pressure at the fluid
outlet port 4. Of course, the second internal space 19, lying on
the flange part 38 of the valve tube 8, which is opposite to the
closing chamber 57, is vented to ambient pressure via channel
46.
[0055] If the piloting valve 50 is switched to its open position,
however, a fluid connection is established between connecting line
47 and third internal space 20 via piloting valve 50 and discharge
line 49. Therefore, the pressure in the closing chamber 57 will
drop to the pressure level of third internal space 20. This is,
because the influx of fluid is limited by throttle 51. Because of
the falling pressure within closing chamber 57, the valve tube 8 is
now again free to move to the right side, i.e. into the open
position of valve unit 6. Whether this movement will actually take
place, or not, depends on the pressure in third internal space 20.
Therefore, the pilot controlled fluid pressure regulator 56 now
works as a standard fluid pressure regulator.
[0056] FIG. 5 is a modification of the pilot controlled fluid
pressure regulator 56, shown in FIG. 4. The presently shown pilot
controlled fluid pressure regulator 58 shows an additional
balancing section 33, which is equivalent to the balancing section
33 of the pressure regulator 28, shown in FIG. 2. In other words,
the fluid pressure regulator 28, shown in FIG. 2, can be modified
by providing a pilot control section 59. This way, a pilot
controlled fluid regulator 58, which is fluid pressure regulated
(in particular towards the high pressure side of the pilot
controlled fluid pressure regulator), can be realised.
[0057] Of course, piloting valve 50 can be designed differently as
well. For example, a manual operation of piloting valve 50 is
possible. Also, piloting valve 50 can be constructed in a way that
intermediary states can be achieved. This can be achieved by
providing an intermediary mechanical position of the piloting valve
50. However, a proportional valve is possible as well. This could
be achieved by a modulated magnetic valve, for example.
[0058] Further information can be drawn from the application, which
was filed by the same applicant on the same date under applicant's
reference number DAN08005PE. The disclosure of said application is
fully integrated into the disclosure of the present application by
reference.
[0059] While the present invention has been illustrated and
described with respect to a particular embodiment thereof, it
should be appreciated by those of ordinary skill in the art that
various modifications to this invention may be made without
departing from the spirit and scope of the present.
* * * * *