Note: Descriptions are shown in the official language in which they were submitted.
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 1 -
A CYLINDER VALVE WITH INTEGRATED PRESSURE REGULATOR
The present invention relates to a cylinder valve with
integrated pressure regulator. Such valves are known in the
art as VIPRs (Valves with Integrated Pressure Regulator).
Such valves are fitted on gas cylinders in order to reduce
the pressure from the gas cylinder (often at a pressure of
300 bar or more) down to an outlet pressure, typically below
10 bar.
Although reference is made to a "cylinder" valve, it will be
understood that the invention is applicable broadly to all
portable pressurised gas containers including gases stored
under pressure as liquids whether they are strictly in the
form of a cylinder or not.
Such cylinders are used to supply gas for a range of
applications including welding and cutting hoses and
torches, gas packaging machines and laboratory equipment.
Using a VIPR this equipment can be connected directly to the
valve outlet without the need for an additional externally
connected regulator.
The regulator needs to be adjustable to allow a user to
supply gas at the required pressure and flow rate for a
given application. For example, different flow rates of
shielding gas are normally requires for different material
thicknesses during welding processes. Further, the majority
of VIPRs need adjusting several times a day to alter the
pressure or flow rate as the cylinder pressure drops and
consequently outlet pressure increases. Conventionally in a
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 2 -
VIPR, the force required to adjust the outlet pressure of
the regulator is provided by the application of a manually
applied torque rotating a hand wheel. The pressure required
is dependent upon the outlet pressure requirements and
increases as the outlet pressure increases. This torque
demand can often be demanding for the user, particularly
when dealing with a high outlet pressure. If the regulator
is intended to be operated using an electric motor
controlled by on-board power supply, the torque and
therefore energy requirement of the regulator may become
prohibitive in terms of the capacity required from the on-
board power supply.
According to a first aspect of the present invention there
is provided a cylinder valve with integrated pressure
regulator as defined in claim 1.
By including a pilot regulator into the housing to supply a
control pressure to the regulator, the torque or power
required to adjust the outlet pressure setting is greatly
reduced. In the case of a manually activated device, this
makes it far easier for a user to make the required
adjustment to the regulator. For an electronic actuator,
this reduces the demand on the on-board power supply.
Pilot operated pressure regulators are known in other
fields. However, these are generally large scale devices in
which the pilot valve is a separate component in its own
housing which is connected to the regulator via a pipe.
Such pilot operated regulators are designed for applications
which require a high level of outlet pressure accuracy.
They are not used to reduce the operating torque required to
CA 02981101 2017-09-27
WO 2016/156519
PCT/EP2016/057116
- 3 -
adjust the regulator as the regulators are operated using
mains power. They are not used in pressurised cylinder
applicators as these rely on direct action mechanical means
for valve closure/opening and pressure adjustment.
Therefore, existing pilot valves are not configured in the
same manner as in the present invention in that they are not
within the housing containing the shut off valve and
regulator. As well as being configured differently, they
are used in an entirely different field for an entirely
different purpose.
The primary drivers of the present invention are to make a
small device as it is required to fit on the cylinder and to
reduce the torque necessary to operate the regulator.
Preferably, therefore, the pilot regulator has a positive
seat valve element. The positive seat valve element is one
which seats on the low pressure side of its corresponding
valve port as opposed to a reverse seat valve which passes
through the port and seats on the high pressure side. Such
a valve element requires a significantly smaller diameter
seat than a reverse seat valve for the same flow
requirement. This allows a smaller piston size for the same
accuracy. The smaller piston size reduces the upward force
from the gas pressure which allows the biasing springs to be
smaller and requires less torque to adjust.
The pilot regulator preferably has an inlet port in
communication with high pressure gas from the cylinder and a
pilot valve element biased towards the inlet port to control
the flow of gas through the inlet port, a biasing element
providing a biasing force on the pilot valve element and
CA 02981101 2017-09-27
WO 2016/156519
PCT/EP2016/057116
- 4 -
being adjustable by an actuator to control the pressure of
pilot gas passing through the inlet port to the regulator to
vary the force on a restricting element in the regulator.
The biasing element may be a single spring positioned
between the actuator and the pilot valve element. However,
preferably, the biasing element is arranged to bias the
pilot valve element open while a balancing biasing element
is positioned between the pilot actuator and the pilot valve
element to provide an opposing force on the pilot valve
element. The presence of the balancing element allows a
smaller package for the pilot regulator.
The pilot valve element may be manually operated, in which
case it requires less effort from a user to adjust the
regulated pressure. Alternatively, the pilot valve element
is operated by a motor. In this case, there may further
comprise a control system to control the operation of the
motor, the control system including a transmitter and
receiver to receive and transmit data concerning the control
of the pilot valve element.
The valve may be provided with a means to display one or
both of the cylinder pressure and the regulated pressure.
However, preferably, it further comprises a single gauge for
receiving and displaying both the cylinder pressure and the
regulated pressure.
This forms a second aspect of the present invention which is
a cylinder valve according to claim 9.
CA 02981101 2017-09-27
WO 2016/156519
PCT/EP2016/057116
- 5 -
An example of a cylinder valve with integrated pressure
regulator will now be described with reference to the
accompanying drawings, in which:
Fig. 1 is a schematic cross-sectional view showing the
operation of the three main elements of the valve;
Fig. 2 is a more detailed cross-section of the pilot
regulator;
Fig. 3 is an axial cross-section in plane III-III in Fig. 4
through a cylinder valve showing the outlet valve;
Fig. 4 is a cross-section in a horizontal plane shown as IV-
IV and regulator in Fig. 3 showing the cross-section of the
pilot regulator and regulator;
Fig. 5 shows the pilot regulator and regulator as shown in
Fig. 1 as applied to an electronically controlled system;
Fig. 6 is a schematic view of a system used with the
electronically controlled device of Fig. 5;
Fig. 7 is a schematic view similar to Fig. 6 in which
process equipment receives gas from more than one bottle;
Fig. 8 is a schematic overview of the layout of a dual gauge
system;
Fig. 9 is a schematic cross-sectional view showing the dual
gauge system;
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 6 -
Figs . 10A to 10C are front views of possible gauge face
layouts; and
Fig. 11 is a view similar to Fig. 1 showing an alternative
layout of the components.
The present invention relates to an improvement to a valve
with integrated pressure regulator (VIPR). Such valves are
known for use on cylinders or bottles of pressurised gas.
Similar valves are also used in health care applications but
have a pre-set pressure and adjustable volumetric flow
output. An example of a known valve is disclosed in EP
0747796.
The improvement provided by the present invention is the
introduction of a pilot regulator and the description below
will focus on this and the manner in which it interfaces
with the regulator and the shut off valve.
This will be described, in particular, with reference to
Figs. 1 to 4. Fig. 1 provides a schematic layout of the
arrangement while Figs. 3 and 4 show the integration of the
various components shown in Fig. 1 into a practical housing.
Fig. 2 provides for the detail of the pilot regulator.
The shut-off valve 1 has a generally conventional
construction. It comprises a shut-off valve element 2 urged
onto a valve seat 3 by a spring 4. The shut-off valve
element 2 and spring 4 are within a chamber which is exposed
to a regulated pressure Pb as described in greater detail
below. This pressure exerts a closing force on the shut off
valve element 2. The shut-off valve element 2 is displaced
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 7 -
from the valve seat 3 by the depression of a spindle 5 which
is pushed downwardly by the operation of a lever (not shown)
connected at opening 6 via an eccentric coupling which
converts rotational movement of the lever into downward
movement of the spindle 5. The return spring 7 biases the
spindle upwardly to assist in the closure of the valve.
Turning of the lever depresses the spindle 5 which opens the
shut-off valve element 2 against the action of the spring 4
and regulated pressure Pl. This causes gas at the regulated
pressure P1 to be emitted from the outlet 8.
The shut-off valve can alternatively be integrated into the
high pressure region upstream of the regulator 10 and pilot
regulator 30.
The regulated pressure P1 is created by a combination of the
regulator 10 and pilot regulator 30 as described below.
Both the regulator 10 and the pilot regulator 30 receive
high pressure gas at a pressure P2 which is the pressure
within the cylinder to which the valve is connected.
The regulator 10 has a regulator element in the form of a
piston 11 slidable within a regulator chamber 12.
Alternatively, a flexible diaphragm or bellows could be
used. The chamber 12 has a stepped bore with a smaller
diameter portion 13 on the high pressure side and a larger
diameter portion 14 on the regulated pressure side. The
piston 11 has a correspondingly stepped construction with a
smaller diameter portion 15 sealed by an 0-ring 16 with the
smaller diameter portion 13 of the chamber. A larger
CA 02981101 2017-09-27
WO 2016/156519
PCT/EP2016/057116
- 8 -
diameter portion 17 of the piston 11 is sealed by an 0-ring
18 with respect to a large diameter portion 14 of the
chamber. A bore 19 extends axially down the centre of the
piston 11 connecting the high pressure side P2 of the
regulator with the regulated pressure side P1 as described
below. A bleed port 30 is provided through the larger
diameter portion 14 of the piston 11. The bleed part 30
allows a flow of gas from the pilot pressure P3 to the lower
regulated pressure P1 and enables the pilot control pressure
to continuously vary. The piston 11 is urged downwardly by
a spring 21 urging a tapered lower end 22 towards a seat 23.
The chamber 12 above the piston 11 is connected to the pilot
regulator 30 via a regulated pressure line 24 and is
connected to the shut off valve 1 via a regulated pressure
outlet line 25. The large diameter portion 14 of the
regulator chamber 12 below the large diameter portion 17 of
the piston 11 is provided with gas at a pilot pressure P3
via a line 26.
The downward force (using the orientation of Fig. 1) on the
piston 11 is a combination of the spring force provided by
spring 21 together with the pressure P1 acting on the
available upwardly facing piston surface. The upward force
on the piston 11 is provided by a combination of the pilot
pressure P3 on the downwardly facing surface of the piston
and the cylinder pressure P2 on the downwardly facing
portion of the smaller diameter portion 15 of the piston.
One example of the pilot regulator 30 will now be described.
The pilot regulator 30 comprises a pilot regulator element
in the form of a piston 31 which is housed in a pilot
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 9 -
regulator chamber 32, the piston 31 is biased upwardly (in
the orientation shown in Fig. 1) by a pilot regulator spring
33 and is biased in the opposite direction by a balancing
spring 34. The force balance on the piston 31 is adjustable
via actuator stem 35 which bears against the top of
balancing spring 34. The net effect of the pilot regulator
spring 33 is less than that of the balancing spring 34. A
downward force is exerted by the pressure P1 and an upward
force by the pilot regulator sping 33. The balancing spring
34 serves to reduce the net effect of the pilot regulator
spring 33 and therefore provides a simple method of
adjusting the overall force balance.The actuator stem 35 is
the means by which the user adjusts the regulated pressure
P1 ultimately emitted from the cylinder and this is done
using a very small force as described in greater detail
below. This either makes the manual adjustment of the
regulated pressure easier for a user or reduces the power
consumption of any electronic actuation assembly.
The surface of the piston 31 in the upper part of chamber 32
receives the regulated pressure P1 via the regulated
pressure line 24, while the downwardly facing surface of the
piston is open to atmosphere via vent 36. A positive seat
pilot regulator valve element 37 extends downwardly from the
piston 31 and seats on a valve seat 38 which can be
significantly smaller than the valve seat 23 of the
regulator 10. The positive seat pilot regulator valve
element 37 passes through an 0-ring seal 39 to seal the
valve seat 38 from being exposed to atmospheric pressure.
As a result of this, the region in the vicinity of the valve
seat 38 is held at the pilot pressure P3 which is
CA 02981101 2017-09-27
WO 2016/156519
PCT/EP2016/057116
- 10 -
transmitted to the regulator along the pilot pressure line
26.
The piston 31 is therefore biased downwardly by a
combination of the spring force from the balancing spring 34
and the relatively low regulated pressure P1 acting on the
large piston surface 31. It is biased upwardly by a
combination of the biasing force from the pilot regulator
spring 33, atmospheric pressure on the lower surface of the
piston 31 and the high cylinder pressure P2 acting on the
positive seat pilot regulator valve element 37. Raising the
actuator stem 35 opens the pilot regulator valve element 37.
This causes P3 to rise, this increases the pressure beneath
piston 11 lifting it and causing P1 to rise.
The pilot regulator valve element is significantly smaller
than the smaller diameter portion 15 of the regulator 10 so
that the surface area exposed to high pressure acting on the
piston 31 is significantly less than the high pressure
acting on the piston 11. As a result if this, the spring
force required to bias the piston 31 can also be
significantly reduced in comparison to a standard regulator
construction.
Although one example has been described here, other
variations are contemplated. The valve elements in the
regulator and pilot regulator could be reverse seat valves,
the pistons in the regulator and pilot regulator could be
replaced by a diaphragm or bellow, and the shut off valve
could be an upstream valve.
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 11 -
This latter arrangement is illustrated in Fig. 11. The
three components, namely the shut off valve 1, regulator 10
and pilot regulator 30 are the same as previously described.
The only difference is that the shut off valve is now
upstream of the regulator 10 and pilot regulator 30. The
pilot regulator 30 operates in exactly the same manner as
before and the various chambers are exposed to the same
temperatures. The only difference is that they receive the
high pressure cylinder gas downstream of the shut off valve
1. While the structure of the shut off valve remains
unchanged, the shut off valve element 2 is now exposed to
the cylinder pressure P2 rather than the regulator pressure
Pl. However, gas at regulator pressure P1 is emitted to the
downstream equipment as before.
Figs. 5 to 7 show the manner in which the previously
described valve is integrated into an electromechanically
actuated device.
In Fig. 5, the regulator 10 and pilot regulator 30 are as
previously described. The actuator stem 35 is provided with
a screw thread and is connected to a motor such as a small
brushed DC motor. The motor is controlled by a control
system comprising a power supply 41 such as a battery, a
memory 42, a means of transmission 43 which may be a wired
connection or any known wireless connection, a receiver 44
which again may have a physical connection or be wireless
and a processor 45. These components form a control module
46 which is connected to the housing for the cylindrical
valve.
CA 02981101 2017-09-27
WO 2016/156519
PCT/EP2016/057116
- 12 -
Fig. 6 shows a use of the arrangement shown in Fig. 5.
Here, the control module 46 is attached to a cylinder C.
The means of transmission 43 and receiver 44 can communicate
with process equipment 47 to make necessary adjustments to
the actuator stem 35 of the pilot regulator 30 to control
the pressure of gas supplied to the process equipment 47
along line 48. This system may also include pressure
sensors in the line 48 and/or process equipment 47.
Communications devices 49 are in two way communication with
the control module 46 to allow a user to monitor and control
the output from the cylinder C.
A variation of this second implementation is shown in Fig. 7
in which two cylinders C supply gas along gas supply lines
48 to a mixing buffer which can supply a mixture of gas to
process equipment 47 via a mixing buffer 50. The control
modules 46 on the cylinders C are controlled to supply gas
in the correct ratios to the mixing buffer 50.
Figs. 8 to 10C show an arrangement of a gauge G which is
particularly suited to use with the present invention.
In particular, the gauge is designed to display to the user
both the cylinder pressure P2 and the regulated pressure P1
on a single gauge.
A cylinder pressure inlet 60 in the gauge G is in
communication with one of the gas paths that is at the
cylinder pressure P2. Similarly, a regulated pressure inlet
61 is in communication with one of the paths at the
regulated pressure Pl. The high pressure inlet 60 leads to
a high pressure bourdon tube 62 which leads to a high
CA 02981101 2017-09-27
WO 2016/156519 PCT/EP2016/057116
- 13 -
pressure needle 63 to indicate on a high pressure scale 64
the level of the high pressure P2. A number of high
pressure gauges are shown in Figs. 10A - 10C. Similarly,
the regulated pressure inlet 61 is connected to a low
pressure bourdon tube 65 connected via a linkage 56 and rack
and pin mechanism 67 to a regulated pressure needle 68 which
displays the level of the regulated pressure to a user on a
regulated pressure scale 69, again as shown in Figs. 10A to
10C. Alternatively a digital display may be used. It would
be appreciated, however, that the dial provides a convenient
and compact way of displaying both pressures to a user.
