[0001] The present invention relates to a fire-fighting system comprising a source of pressurised
fire-fighting fluid, at least one valve, a fluid conduit connecting the source and
the valve, and a control system for actuating the valve.
[0002] The invention especially relates to a fire-fighting system for local fire-fighting
on locations of enhanced risk of fire, such as various locations in an engine room
e.g. in a ship. In case of a local fire the local fire-fighting system may extinguish
the fire without the entire engine room being involved, thereby limiting the damage
due to fire-fighting fluids and the effort needed to extinguish the fire.
[0003] The invention also relates to a valve usable in the fire-fighting system.
[0004] When the fire-fighting system is installed the valve is usually connected e.g. to
a nozzle for emitting fire-fighting fluid. In known systems the valve comprises a
solenoid to be operated electrically by the control system, which for various reasons
may be a drawback.
[0005] Therefore it is an object of the present invention to provide a fire-fighting system
with an alternative valve.
[0006] The object is fulfilled in that the valve is connected to the control system by a
second fluid conduit, the control system actuating the valve through the second fluid
conduit by fluid pressure. Hereby is obtained that electricity is avoided in the vicinity
of the valve that might be exposed to the fire-fighting fluid and larger lifts of
valve components at a given force may be obtained.
[0007] In an embodiment the source of pressurised fire-fighting fluid comprises a pump pressurising
when activated the fire-fighting fluid. Thus the system may be connected to a low
pressure supply of fire-fighting fluid while still providing sufficient pressure of
the fire-fighting fluid for the nozzle to function as intended.
[0008] In an embodiment the control system actuates the valve by gas or air pressure. Hereby
liquids are avoided in the vicinity of the control system, which is usually electrically
operated.
[0009] In an embodiment a compressor driven by the pressurised fire-fighting fluid provides
pressurised air for actuating the valve. Hereby external sources of pressurised gas
or air for activating the valve are avoided making the system more self-contained
and simple.
[0010] In an embodiment the compressor comprises a piston driven in one direction by the
pressurised fire-fighting fluid and in an opposite direction by a spring. Hereby a
very simple construction is obtained.
[0011] In an embodiment the control system comprises an electromechanical valve, such as
a solenoid valve, for controlling the fluid pressure for actuating the valve. Hereby
any electrics and electronics of the fire-fighting system may be concentrated in a
housing of the control system
[0012] In an embodiment the valve comprises a connector for connecting to a nozzle. This
facilitates the installation of the system, e.g. in an engine room.
[0013] In an embodiment the fire-fighting fluid is a liquid and in a further embodiment
the source comprises a connector for connecting the pump to a liquid container. This
facilitates the installation of the system, e.g. in an engine room.
[0014] In an embodiment the fire-fighting system is configured as a mobile unit. This facilitates
industrial production of the fire-fighting system in a workshop for subsequent installation
at a location where fire-protection is needed.
[0015] In an embodiment the fire-fighting system comprises a plurality of valves independently
actuated by the control system. This provides for s single fire-fighting system protecting
a number of locations e.g. in an engine room.
[0016] Though an engine room in a ship is used as an example it should be understood that
the fire-fighting system according to the invention is usable in other place such
as in buildings etc.
[0017] As mentioned above the invention also relates to a valve usable in the fire-fighting
system.
[0018] Thus the present invention also relates a valve for opening and closing a fluid main
passage, comprising: a valve housing with a valve chamber; a main valve body accommodated
inside the valve chamber; a fluid inlet; a fluid outlet, the main valve body being
movable between a closing position closing the fluid main passage and an opening position,
the main valve body dividing the valve chamber into a first valve chamber portion
and a second valve chamber portion, the fluid inlet being in fluid connection with
the first valve chamber portion; a first passage between the fluid inlet and the second
chamber portion; a second valve body movable between an opening position and a closing
position of said second valve body; and a second passage out of the second valve chamber
portion, said second passage being open when the second valve body is in its opening
position.
[0019] Valves of this art are known e.g. from
US-A-4 848 721,
US-A-5 048 790 and
US-A-5 529 387, which all disclose valves having a restricted opening constituting part of the first
passage. Due to the first passage fluid enters the second valve chamber portion, and
if the second passage is closed pressure builds up that force the main valve body
towards a valve seat to close the valve. Thus the valve chamber and the main valve
body are configured so that the areas of the main valve body is exposed to the fluid
pressure in the second valve chamber portion and the first valve chamber portion,
at least when the valve is closed, result in a net force is acting on the main valve
body to keep it in its closed position, when the pressure of the fluid at the inlet
is fully present in the second valve chamber portion. A spring may be present to assist
moving the main valve body from an opening position to the closing position. The second
valve body opens and closes the second passage thus allowing the pressure in the second
valve chamber portion to escape when opening the second passage whereby the main valve
body raises from the seat to open the fluid main passage. These prior art valves are
all operated by means of solenoids activating the second valve body.
[0020] A problem of these prior art valves is that due to small dimensions of the restricted
opening impurities present in the fluid controlled by the valve may tend to block
the restricted opening thus preventing proper function of the valve.
[0021] US-A-3 428 090 gives an example of a pneumatically operated valve.
[0022] In certain applications e.g. fire-fighting equipment in ships, especially local fire-fighting
equipment, impurities in a fire-fighting liquid is a problem in case of valves of
the above art. Further the environments e.g. in engine rooms in ships, where local
fire-fighting equipment is used, are corrosive.
[0023] It is an object of the present invention to provide a valve that avoids the above
mentioned problem of prior art valves.
[0024] This is achieved in a valve wherein said second valve body is placed at said first
passage between the fluid inlet and the second valve chamber portion, said first passage
being blocked when the second valve body is in its opening position, and said first
passage being open when the second valve body is in its closing position. Hereby is
obtained that the first passage need not comprise (permanently) restricted openings
that tend to be blocked by impurities.
[0025] It should be noted that the terms opening position and closing position in relation
to the second valve body refer to positions of the second valve body in which the
valve opens and closes the fluid main passage, respectively.
[0026] When the valve is closed any leak from the second valve chamber portion should be
small and preferably the second valve chamber portion is closed apart from the passage
to the fluid inlet.
[0027] Thus in one embodiment the valve comprises a vent comprising at least one aperture,
said vent forming part of the first passage from the fluid inlet to the second valve
chamber portion, when the second valve body is in its closing position, the second
valve body blocking in its opening position passage from the fluid inlet to said vent
while allowing passage from said vent to a space in the valve blocked from the passage
to the fluid inlet, said space being in fluid connection with the surroundings of
the valve, said vent and said space thereby constituting at least part of second passage.
Hereby is obtained that the vent, when the second valve body is in its closing position,
serves to connect the second valve chamber portion with the fluid inlet for pressure
to build up in the second valve chamber portion in order to move the main valve body
to its closing position, and when the second valve body is in its opening position,
serves to relieve the pressure in the second valve chamber portion to the surroundings
of the valve.
[0028] In a further embodiment the valve comprises a hollow element with a wall, the second
valve body being accommodated in the hollow element to divide an internal space of
the hollow element into a first part and a second part, said vent being present in
the wall of the hollow element, the second valve body providing in its closing position
for connection between the vent and said first part, and the second valve body providing
in its opening position for connection between the vent and said second part. In a
still further embodiment the hollow element is a tubular element having an axis, the
second valve body being axially slidable in the tubular element, to expose the vent
to said first part of the internal space or to the second part of the internal space,
which constitutes said space in the valve blocked from the passage to the fluid inlet.
Hereby a simple construction is obtained.
[0029] In one embodiment a fluid actuated actuating element is connected to the second valve
body for moving the second valve body between its opening and closing positions. This
provides an alternative to electric activation which in some applications may be undesirable.
[0030] In a further embodiment the actuating element comprises a piston. Hereby a simple
construction is obtained.
[0031] In a further embodiment where the valve comprises a tubular element accommodating
the second valve body the piston is slidably accommodated in the tubular element and
slidably sealed against the wall of the tubular element. Hereby a further simple construction
is obtained.
[0032] In a further embodiment the tubular element in sequence along its axis: accommodates
the piston; comprises a second vent; comprises the first vent; comprises a through
opening in fluid connection with the fluid inlet; and comprises a third vent in fluid
connection with the surroundings of the valve, and that an elongate pilot element
is accommodated in the tubular element and comprises: the piston; the second valve
body situated near the first vent; and a third valve body situated near the third
vent to open said third vent towards the first part of the internal space of the tubular
element when the second valve body is in its opening position and to block the third
vent from the first part of the internal space of the tubular element when the second
valve body is in its closing position. Hereby on one hand a simple construction is
obtained and on the other hand the third valve body and the third vent provide for
pressure relief of the first part of the internal space of the tubular element when
the first passage is blocked while the second vent provides for communication of the
second passage with the surroundings.
[0033] In a further embodiment the tubular element is at one end adjacent the piston closed
by a manually actuated slidable plug element. Hereby a possibility of manual actuation
of the valve is obtained e.g. for the case that automatic fluid actuation should fail.
[0034] In one embodiment the valve housing comprises a first tubular member, the main valve
body comprises a second tubular member having a first end with a first end face, a
second end and a circumferential wall, the first valve chamber portion being defined
by the circumferential wall and the second valve chamber portion being defined by
the first end face. Hereby is obtained that substantial parts of the valve may be
constructed from plastic material preferably fibre reinforced and durable in a corrosive
environment at relatively low costs.
[0035] In a further embodiment comprising a tubular element accommodating slidably the second
valve body, the tubular element extends axially through the second tubular member
to form an annular space there between, said annular space being closed adjacent the
second end, a coaxial annular wall member of the valve housing extending slidably
into the annular space in a sealing manner. This embodiment further facilitates construction
of the valve from plastic material.
[0036] In a further embodiment where the tubular element accommodates an elongated pilot
element a second through opening is provided in the second tubular member to constitute
a part of the first passage, the first through opening constituting another part of
the first passage. Hereby a simple construction is obtained.
[0037] In an embodiment said second end rests, possibly through a sealing element, at a
valve seat to close the fluid main passage when the main valve body is in its closing
position.
[0038] In the following the invention will be explained in more detail by way of example
with reference to the accompanying drawing, in which
Fig. 1 shows an embodiment of a fire-fighting system according to the invention,
Fig. 2 is a diagram of the fire-fighting system of Fig. 1,
Fig. 3 shows diagrammatically an embodiment of a compressor used in the fire-fighting
of Fig. 1,
Fig. 4 is a perspective view of an embodiment of a valve according to the invention,
Fig. 5 is a side view of the valve of Fig. 4,
Fig. 6 is a top view of the valve of Fig. 4,
Fig. 7 shows a section along line Vll-Vll in Fig. 6,
Fig. 8 shows a section along line Vlll-Vlll in Fig. 6, and
Fig. 9 is a view corresponding to Fig. 8 but showing a part of the valve in another
position.
[0039] The fire-fighting system shown in Figs. 1 and 2 comprises a chassis 1 carrying a
pump 3 driven by a motor 5, a stand 7 carrying a number of valves 9, four valves 9
in the present embodiment, a fluid conduit 11 connecting the pump 3 and the valves
9, a compressor 13 and a control system 15. As indicated the fluid conduit 11 comprises
a check valve 17 and a manometer 19.
[0040] Second fluid conduits 21 connect the control system 15 and the valves 9. A third
fluid conduit 23 connects the compressor 13 and the control system 15. The control
system 15 comprises solenoid valves 25 feed through the third conduit 23 to direct
when actuated fluid pressure to the valves 9.
[0041] The valves 9 each comprise a connector 27 for connecting the respective valve with
e.g. a nozzle (not shown).
[0042] The pump 3 comprises a connector 29 for connecting the pump to a reservoir of fire-fighting
fluid, preferably fire-fighting liquid, such as water, e.g. a water tank or water
container (not shown).
[0043] Being build on a chassis 1 the fire-fighting system is mobile and can be manufactured
in a factory to be transported to a place of use where the connectors 27 and 29 are
connected with e.g. pipes or hoses leading to nozzles and a water container, respectively.
[0044] In the embodiment shown in Fig. 3 the compressor 13 has a simple construction comprising
a cylinder 31 with a piston 33, a piston rod 35 extending in a sealing manner through
a partition 37 in the cylinder 31 to an abutment 39 for a spring 41 housed in a closed
end of the cylinder 31. An air space 43 of the cylinder 31 between the piston 33 and
the partition 37 is connected to the ambient air through a second check valve 45 and
to the third fluid conduit 23 through a third check valve 47. A liquid space 49 of
the cylinder 31 opposite the piston 33 relative to the air space 43 is connected to
a branch 51 of the fluid conduit 11.
[0045] The compressor 13 works as follows:
When the pump 3 is not running pressure in the fluid conduit 11 is low and the spring
41 drives the piston away from the partition 37 expanding the air space 43, ambient
air being sucked in through the second check valve 45. When subsequently the pump
3 is activated pressure rises in the fluid conduit 11 and fire-fighting liquid enters
the cylinder 31 driving the piston 33 towards the partition 37 whereby the air in
the air space 43 is compressed and is driven out through the third check valve 47
to the extend it is possible due to the pressure rising correspondingly in the third
fluid conduit 23 downstream of the third check valve 47.
[0046] The fire-fighting system works as follows:
The fire-fighting system may e.g. be installed in an environment, such as an engine
room, divided into fire-protection sections each comprising a fire-alarm and a nozzle,
such as a fog spray nozzle, for spreading fire-fighting fluid, or more nozzles grouped
together, whereby each valve 9 is connected to a respective nozzle or group of nozzles.
[0047] When the fire-fighting system is not activated, e.g. due to the apparent absence
of a fire, the motor is not energised and the fluid conduit 11 and the compressor
13 are pressure-less.
[0048] When a fire-alarm is released the control system 15 energises the motor 5 to drive
the pump 3, whereby the pressure in the fluid conduit 11 rises providing for pressurised
fire-fighting fluid at the valves 9. Also the pressurised fluid in the fluid conduit
11 activates the compressor 13 as explained above providing for pressurised air. The
control system 15 further activates the relevant valve or valves 9 by opening the
relevant solenoid valve(s) 25 sending fluid or air pressure to the valves in question
provoking the same to open. Thereby the pressurised fire-fighting fluid is allowed
to the respective nozzles.
[0049] Figs. 4 to 9 show an embodiment of the valve 9.
[0050] In the following "up", "upper", "down", "lower", "above", "below", etc. relates to
the position of the valve shown in Figs. 7 to 9.
[0051] The valve has a valve housing comprising a tubular valve housing member 61, which
in an embodiment is made of plastic material such as glass fibre reinforced polyamide,
surrounded by a cylindrical steel mantel having an upper section 63 and a lower section
65. The valve housing member 61 has an axis A and comprises a partition 67 having
a through hole constituting a fluid outlet 69. Above the partition 67 a valve chamber
71 is provides, which accommodates a main valve body 73. The valve housing further
comprises a sealing member 75, which is secured by an upper flange member 77, to close
an upper end of the valve housing member 61. The sealing member 75 is sealed against
the valve housing by an O-ring (not shown) accommodated in a groove 79. At the lower
end of the valve housing member 61 a lower flange member 81 with a tubular portion
83 is provided. The tubular portion 83 is sealed against the valve housing member
61 by means of O-rings (not shown) accommodated in grooves 85. The upper and lower
flange members 77, 81 are secured by stay bolts (not shown) extending through opposite
holes 87 (see Figs. 4 and 6) in the flange members 77, 81.
[0052] The valve chamber 71 has a lower section with a smaller diameter and an upper section
with a larger diameter. In the lower section the main valve body 73 has a first seal
89 provided by an O-ring (not shown) accommodated in a circumferential groove in a
circumferential projection 91. In the upper section the main valve body 73 has a second
seal 93 provided by an O-ring accommodated in a groove of a flange like portion 95
of the main valve body 73. The flange like portion 95 provides a first end face of
the main valve body 73. The first seal 89 defines a first valve chamber portion 97
below the circumferential projection 91, and the second seal 93 defines a second valve
chamber portion 99 above the flange like portion 95. An opening in the valve housing
61 provides a fluid inlet 101 (see Fig. 7) opening into the first valve chamber portion
97. A dead space portion 102 of the valve chamber between the first seal 89 and the
second seal 93 is vented towards the surroundings through a dead space vent 103 (see
Figs. 5 and 8) in the valve housing 61.
[0053] The main valve body 73 comprises second tubular member 105 with a circumferential
wall 107 carrying at an intermediate position the circumferential projection 91 and
carrying at a first end the flange like portion 95. A tubular element 109 extends
coaxially through the second tubular member 105 providing an annular space 111 therebetween.
At a second end of the second tubular member opposite the first end, the second tubular
member 105 and the tubular element 109 are interconnected by an end member 113 attached
to the tubular element 109 and an annular connecting element 115 between the end member
113 and the second tubular member 105, thus closing the annular space 111 at said
second end. At the second end of the second tubular member 105 between the latter
and the end member 113 an annular sealing element 117 is provided.
[0054] A coaxial annular wall member 119 is suspended from the sealing member 75 and extends
into the annular space 111. The annular wall member 119 is sealed in a slidable manner
against the second tubular member 105 as well as against the tubular element 109 through
O-rings (not shown) accommodated in respective grooves 121. A compression spring 123
is accommodated in the annular space 111 and forces the main valve body 73 downwards
due to abutment against the annular connecting element 115 and the annular wall member
119. Thus the compression spring 123 forces the sealing element 117 of the main valve
body against a valve seat provided by the edge of the through hole in the partition
67 as seen in Figs. 7 to 9.
[0055] The sealing member 75 is sealed against the tubular element 109 in a slidable manner
through an O-ring (not shown) accommodated in a groove 125.
[0056] The tubular element 109 together with the end member 113 comprises an internal space
127 accommodating an elongated pilot element 129. The wall of the internal space 127
comprises a number of through openings, namely a vent 131 placed above the O-rings
of the coaxial annular wall member 119 and comprising in the present embodiment two
opposite apertures, through openings 133 connecting the internal space 127 with the
annular space 111, a second vent 135 placed outside the valve housing on the opposite
side of the sealing member 75 relative to the main valve body 73, etc., and a third
vent 137 provided in the end member 113 below the sealing member 117 i.e. outside
the valve chamber 71, at least when the main valve body 73 is in its closing position
as shown in Figs. 7 to 9.
[0057] The elongate pilot element 129 comprises a central rod 129a carrying a second valve
body 139 comprising a groove 141 accommodating an O-ring (not shown) sealing in a
slidable manner the second valve body 139 against the wall of the internal space 127,
a piston element 143 at an upper end of the central rod 129a and third valve body
145 at a lower end of the central rod 129a. The piston element 143 and the third valve
body 145 are both provided a respective groove 147, 149 accommodating respective O-rings
(not shown) to seal the piston element 143 and the third valve body 145 against the
wall of the internal space 127 in a slidable manner. A second spring 150 below the
piston element 143 forces the elongate pilot element 129 upwards (as seen in Figs.
7 to 9).
[0058] The second valve body 139 divides the internal space 127 into a lower first part
127a and an upper second part 127b.
[0059] A second through opening 151 is provided in the circumferential wall 107 to provide
fluid connection between the first valve chamber portion 97 and the annular space
111.
[0060] Third through openings 153 in the coaxial annular wall member 119 provide fluid connection
between the second valve chamber portion 99 and a dead space 155 between the coaxial
annular wall member 119 and the tubular element 109.
[0061] At an upper end, opposite the end member 113, the tubular element 109 has a cylindrical,
expanded portion 157 defined by a shoulder 159. A plug element 161 is slidably fitted
in the expanded portion 157 and is sealed against the wall thereof by an O-ring (not
shown) accommodated on a groove 163. The plug element 161 is secured by a transverse
pin 165. L-shaped slots 167 in the wall of the expended portion 157 (see Fig. 5) provides
for placing and maintaining the plug element 161 in different axial positions as shall
be explained below. The plug element 157 comprises a vertical (as seen in Fig. 7)
through channel 169 with an upper connector 171. The channel 169 opens into a cylinder
space 173 between the plug element 161 and the piston element 143.
[0062] The valve 9 provides a fluid main passage via the fluid inlet 101 through the first
valve chamber portion 97 and through the outlet 69, when the main valve body is in
an opening position as will be explained below. To provide for connecting the valve
9 with a fluid conduit the valve 9 is attached to a skew T-shaped fitting 175 whereby
nuts 177 attached to the steel mantel 63, 65 provides for fastening a leg or branch
of the T-shaped fitting 175 by means of second nuts 179 and threaded rods (not shown).
A cross bar of the T-shaped fitting 175 is at either end provided with a connecting
piece 181 and a sleeve 183, respectively, for mutual connection of a number of such
T-shaped fittings to provide a manifold connecting a number of valves 9 to a fluid
conduit such as fluid conduit 11 (see Figs. 1 and 2).
[0063] The valve works as follows:
In use the valve 9 is connected to a fluid inlet conduit which is attached to the
inlet 101, in the embodiment shown through the T-shaped fitting 175, and possibly
to a fluid outlet conduit (not shown), which may be attached to the lower flange member
81 through an internal thread (not shown) in the tubular portion 83, which thus functions
as a connector 27. A second fluid conduit, such as fluid conduit 21 is connected to
the channel 169 via the connector 171.
[0064] In case of low pressure in the fluid inlet conduit the compression spring 123 will
keep the main valve body 73 in its closing position as shown in Figs. 7 to 9.
[0065] When the inlet 101 is pressurized and the elongated pilot element 129 is in a closing
position as shown in Figs. 7 and 8 a first passage extends from the inlet 101, through
the first valve chamber portion 97, the second through opening 151, the annular space
111, the through openings 133, the lower first part 127a of the internal space 127,
the vent 131, the dead space 155, and the third through openings 153 to the second
valve chamber portion 99. Thus equal pressure is present in the first valve chamber
portion 97, the second valve chamber portion 99 and the annular space 111. The pressure
in the first valve chamber portion 97 will force the main valve body 73 upwards away
from its closing position i.e. towards an opening position allowing fluid access past
the sealing element 117 and out through the outlet, whereas the pressure in the second
valve chamber portion 99 and in the annular space 111 will force the main valve body
73 towards the closing position. Since the relevant areas in the second valve chamber
portion 99 and in the annular space 111, i.e. the areas of the flange like portion
95 and the annular connecting element 115, mainly, are larger than the relevant areas
in the first valve chamber portion 97, i.e. the downwards facing area of the circumferential
projection 91 and the downwards facing area or the second tubular member 105 adjacent
the annular sealing element 117, mainly, a net force is acting on the main valve body
73 towards its closing position. I.e. the pressure at the inlet 101 keeps the valve
9 closed.
[0066] Further in the closing position of the elongate pilot element 129 the lower first
part 127a of the internal space 127 is closed apart from said first passage.
[0067] To open the valve 9 the elongate pilot element 129 is moved from its closing position
shown in Figs. 7 and 8 to its opening position shown in Fig. 9. How the elongate pilot
element 129 is moved will be explained further below.
[0068] When the elongate pilot element 129 is moved to its opening position mainly the second
valve body 139 is moved from its closing position shown in Figs. 7 and 8 to its opening
position shown in Fig. 9. Whereas the second valve body 139 in its closing position
opens the first passage as explained above, in its opening position the second valve
body 139 is positioned on the opposite side of the vent 131, relative to its closing
position, and thus the second valve body 139 closes the first passage, but opens a
second passage extending from the second valve chamber portion 99, through the third
through opening 153, the dead space 155, the vent 131, the upper second part 127b
of the internal space 127, and the second vent 135 to the surroundings of the valve
9.
[0069] Thus the second valve chamber portion 99 is rendered pressure-less and since the
relevant area of the first valve chamber portion 97 is larger than the relevant area
of the annular space 111 a net force acts on the main valve body 73 to move it away
from its closing position.
[0070] It should be noted that in the situation presently discussed the force of the compression
spring 123 is weak relative to the forces of the pressurised fluid at the inlet 101.
[0071] However when the elongate pilot element 129 is moved to its opening position the
third valve body 145 is moved to a position in which the third vent 137 is open towards
the lower first part 127a of the internal space 127. Thus a third passage exists from
the annular space 111, through the through openings 133, the lower first part 127a
of the internal space 127, and the third vent 137 to the surroundings of the valve
9 in the fluid outlet conduit, if present. Thus the annular space 111 is relieved
of pressure enhancing the net force acting on the main valve body 73 towards its opening
position. It is noted that the overall aperture of the through openings 133 are larger
than the overall aperture of the second through opening 151.
[0072] When the pressure in the first valve chamber portion 97 drives the main valve body
73 towards its raised (relative to the position of the valve in Figs. 7 to 9) opening
position (not shown) fluid is expelled from the second valve chamber portion 99 through
the second passage and fluid is expelled from the annular space 111 mainly through
the third passage.
[0073] When the main valve body 73 is moved towards its raised opening position an annular
residual part of the second valve chamber portion is left between the circumferential
wall 107 and the coaxial annular wall member 119 avoiding a blockage of the third
through openings 153 and the main valve body 73 may be raised to an opening position
in which the flange like portion 95 abuts on the sealing member 75.
[0074] For moving the elongate pilot element 129 from its closing position shown in Figs.
7 and 8 to its opening position shown in Fig. 9 the cylinder space 173 is pressurized
through the channel 169 and the conduit connected threrewith. The pressure will drive
the piston 143 and the rest of the elongate pilot element 129 against the force of
the second spring 150 to the opening position of the elongate pilot element 129 with
the piston abutting on the shoulder 159.
[0075] It is also possible manually to move the elongate pilot element 129 by actuating
manually the plug element 161 via the transverse pin 165 by driving the latter through
the L-shaped slots 167 to depress the piston 143 and subsequently turn the transverse
pin 165 through a circumferential part of the L-shaped slots 167 into a position in
which the plug element will be maintained by friction under influence of the second
spring 150 through the piston 143. When the elongate pilot element 129 is thus manually
brought into its opening position the opening of the valve may be assisted by pulling
the transverse pin 165 upwards thus raising the tubular element 109 and the main valve
body 73 together with it. This may i.a. be used for emptying the valve 9 and connected
conduits.
[0076] Apart from the valve housing member 61 also main valve body 73, the tubular element
109 and the T-shaped fitting 175 may be made from glass fibre reinforced polyamide.
The sealing member 75 and the coaxial annular wall member 119 may e.g. be made from
a plastic material without glass reinforcement such as POM (polyoxymethylene). Other
parts swept in use by the fluid passing through the valve are preferably made from
acid-proof steel.
1. A fire-fighting system comprising a source (2) of pressurised fire-fighting fluid,
at least one valve (9), a fluid conduit (11) connecting the source and the valve,
and a control system (15) for actuating the valve (9), characterized in that the valve (9) is connected to the control system (15) by a second fluid conduit (21),
the control system actuating the valve through the second fluid conduit by fluid pressure.
2. A fire-fighting system according to claim 1, characterized in that the source of pressurised fire-fighting fluid comprises a pump (3) pressurising when
activated the fire-fighting fluid.
3. A fire-fighting system according to claim 1 or 2, characterized in that the control system (15) actuates the valve (9) by gas pressure.
4. A fire-fighting system according to claim 3, characterized by a compressor (13) driven by the pressurised fire-fighting fluid to provide pressurised
air for actuating the valve (9).
5. A fire-fighting system according to claim 4, characterized in that the compressor (13) comprises a piston (33) driven in one direction by the pressurised
fire-fighting fluid and in an opposite direction by a spring (41).
6. A fire-fighting system according to any of the preceding claims, characterized in that the control system comprises an electromechanical valve (25), such as a solenoid
valve, for controlling the fluid pressure for actuating the valve (9).
7. A fire-fighting system according to any of the preceding claims, characterized in that the valve (9) comprises a connector (27) for connecting to a nozzle.
8. A fire-fighting system according to any of the preceding claims, characterized in that the fire-fighting fluid is a liquid.
9. A fire-fighting system according to claims 2 and 8, characterized in that the source (2) comprises a connector (29) for connecting the pump to a liquid container.
10. A fire-fighting system according to any of the preceding claims, characterized by being configured as a mobile unit.
11. A fire-fighting system according to any of the preceding claims, characterized by comprising a plurality of valves (9) independently actuated by the control system
(15).