U.S. patent number 3,703,930 [Application Number 05/147,485] was granted by the patent office on 1972-11-28 for automatic sprinkling system.
This patent grant is currently assigned to FMC Corporation. Invention is credited to Wilton S. Lofstrand, John G. Montgomery.
United States Patent |
3,703,930 |
Lofstrand , et al. |
November 28, 1972 |
AUTOMATIC SPRINKLING SYSTEM
Abstract
An automatic sprinkling system for a plurality of missiles or
other highly combustible objects includes sprinkler heads arranged
to supply streams of water individually to each missile. A fire
detection means is provided for each missile and a control valve
controls the flow of water to the sprinkler heads for each missile
with the detection means being hydraulically connected with the
control valve so as to open the same upon the actuation of the
detection means. A system of check valves and control lines
interconnects all of the control valves so that upon actuation of
the detection means for any one missile the control valves of each
of the adjacent valves will be opened along with the control valve
for the missile which is on fire whereupon a maximum supply of
water will be delivered immediately to the area where it is needed.
The invention herein described was made in the course of or under a
contract with the Department of the Navy.
Inventors: |
Lofstrand; Wilton S.
(Minneapolis, MN), Montgomery; John G. (Arlington, VA) |
Assignee: |
FMC Corporation (San Jose,
CA)
|
Family
ID: |
22521753 |
Appl.
No.: |
05/147,485 |
Filed: |
May 27, 1971 |
Current U.S.
Class: |
169/60; 89/1.812;
169/54; 169/16 |
Current CPC
Class: |
A62C
37/38 (20130101); A62C 35/60 (20130101); A62C
3/00 (20130101); A62C 3/06 (20130101); F42B
39/16 (20130101) |
Current International
Class: |
F42B
39/00 (20060101); A62C 35/60 (20060101); A62C
35/58 (20060101); A62C 37/38 (20060101); A62C
37/00 (20060101); F42B 39/16 (20060101); A62C
3/00 (20060101); A62c 003/00 () |
Field of
Search: |
;169/1R,2R,16,42 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wood, Jr.; M. Henson
Assistant Examiner: Culp, Jr.; Thomas C.
Claims
What is claimed is:
1. An automatic sprinkling system comprising a plurality of spaced
sprinkling heads with each head being arranged to deliver water to
a predetermined area, a control valve for each sprinkling head
connected so as to control the flow of water thereto, a water
supply line for supplying water to each of said control valves,
control means for each control valve for actuating the valve to
permit water to flow therethrough, fire condition sensing means
associated with each control valve to sense the presence of a fire
in the area associated therewith for operating the associated
control means so as to permit flow through the sprinkler head which
delivers water to the area with a fire condition and for
simultaneously operating the control means associated with each
adjacent area to deliver water to each area immediately adjacent to
the area with a fire condition and to no other area without the
actuation of further fire condition sensing means.
2. An automatic sprinkling system according to claim 1 wherein each
of said control valves comprise a differential pressure valve which
is hydraulically controlled through the pressure in a hydraulic
control line and wherein each of said control means comprises said
hydraulic control line, a trigger valve for relieving pressure in
said hydraulic control line, means connecting said fire condition
sensing means to said trigger valve to open the trigger valve upon
the actuation of the sensing means, and at least a pair of
secondary valves hydraulically connecting said trigger valve with
each of the hydraulic control lines associated with the control
valves of the sprinkling heads of the said immediately adjacent
areas.
3. An automatic sprinkling system according to claim 2 wherein both
said trigger valve and said secondary valves comprise check
valves.
4. An automatic sprinkling system according to claim 1 wherein said
fire condition sensing means comprises a pressure actuated sensor
positioned beneath a combustible object located in the area
associated therewith.
5. An automatic sprinkling system according to claim 1 wherein said
fire condition sensing means comprises a heat actuated sensing
means located at an elevated position in the area associated
therewith.
6. An automatic sprinkling system according to claim 1 wherein said
fire condition sensing means comprises both a heat actuated sensing
means located in an elevated position in the area associated
therewith and a pressure actuated sensing means positioned beneath
a combustible object in said area associated therewith.
7. An automatic sprinkling system according to claim 2 including a
control tank charged too a predetermined pressure, a primary
control line connecting each of said hydraulic control lines to
said control tank, and means providing communication between said
primary control line and said water supply line.
8. An automatic sprinkling system according to claim 7 including a
check valve in said water supply line allowing water to be
delivered thereto at a pressure which is less than said
predetermined pressure after the actuation of one of said fire
condition sensing means.
9. An automatic sprinkling system according to claim 7 including
means for simultaneously relieving the pressure in each of said
hydraulic control lines for actuating all of said control valves
and the sprinkler heads connected thereto.
10. An automatic sprinkling system for providing continuous
sprinkling to an area which includes a plurality of combustible
objects located at predetermined spaced positions, a water supply
line for supplying water to each of said positions, a plurality of
injector nozzles positioned beneath each of said objects and
connected to said water supply line to deliver water therefrom to
the lowermost surfaces of said objects, a pressure responsive
member operatively associated with each of said nozzles to normally
prevent the passage of water therethrough but which is arranged to
be moved under the pressure of flames or expanding gases emanating
from the associated combustible object to open said nozzle,
hydraulic means connecting each of said pressure responsive members
to an overlying sprinkling system, said sprinkling system being
provided with a plurality of sprinkling heads arranged so as to
overlie each of said combustible objects, and control means
operable through the actuation of one of said hydraulic means to
provide automatic sprinkling to the combustible object associated
with said hydraulic means and to the combustible objects in said
area which are immediately adjacent to said combustible object
associated with said hydraulic means.
11. An automatic sprinkling system for providing continuous
sprinkling to an area which includes a plurality of combustible
objects located at predetermined spaced positions, a water supply
line for supplying water to each of said positions, a plurality of
injector nozzles positioned beneath each of said objects and
connected to said water supply line to deliver water therefrom to
the lowermost surfaces of said objects, a pressure responsive
member operatively associated with each of said nozzles to normally
prevent the passage of water therethrough but which is arranged to
be moved under the pressure of flames or expanding gases emanating
from the associated combustible object to open said nozzle, a
sprinkling head overlying each of said combustible objects, a
control valve operatively associated with each sprinkling head to
control the flow of water thereto, a hydraulic control line
connecting the pressure responsive member and the control valve
associated with each of said combustible objects, and means
operatively associated with each of said pressure responsive
members for relieving the pressure in the associated hydraulic line
to open the control valve and permit the flow of water through said
sprinkling head.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to automatic sprinkling systems for
providing a plurality of continuous streams of water or other
fluids to quench fires within a predetermined area, and more
particularly, it pertains to the means for controlling such
automatic sprinkling systems.
2. Description of the Prior Art
The storage of a plurality of highly combustible objects within a
given area poses many problems for automatic sprinkling systems
which have been devised for operation upon the detection of a fire
within the area to supply the necessary quantities of water to
quench the flames before serious fire damage results. Typically,
such sprinkling systems include a plurality of sprinkling heads
which are strategically placed so as to spray water over the entire
area or at least that portion thereof where a fire is likely to
start. Such automatic sprinkling systems may be of the "wet type"
or the "dry type." The wet type sprinkling systems provide water at
each sprinkler head under the control of a valve at the sprinkler
head while, in a typical dry type system, a power-operated valve in
the main supply line is opened upon the detection of a fire to
release water to all of the sprinkler heads at once. The dry type
system obviously is the most basic and the least expensive, but it
lacks the necessary speed in response to the detection of a fire
condition so as to make it practical for many applications. The wet
type system, on the other hand, obtains effective sprinkling sooner
after the detection of the fire condition but, in order to be
effective, all of the sprinkler heads are generally turned on upon
the actuation of any one fire detection means.
The detection devices are often built into the sprinkler heads
themselves and may comprise, for example, fusible plug valves which
release control line pressure in the sprinkler head valve to open
the same. Typically, the release of control line pressure in one
valve results in the release of control line pressure in each of
the other valves in the system to also c open these valves and
obtain complete sprinkling. Since any automatic sprinkling system
has only a limited amount of pumping capacity available at any
given time (especially for a sudden unexpected emergency such as a
fire), the amount of water which can be delivered to any given set
of sprinkling heads is thereby limited; however, it may be only one
set of adjacent sprinkling heads out of many heads which need be
activated in order to extinguish the fire, particularly if the
system response is rapid.
One particular problem in this regard occurs aboard naval vessels
which may store within a given area a plurality of highly
combustible objects such as solid state ballistic missiles. In case
of accidental ignition of a missile, or ignition caused by enemy
attack with penetrating ammunition or shrapnel, a tremendous amount
of flames and heat are almost instantly given off from the ignited
missile which, if unchecked, can cause serious damage to the vessel
and may even result in the sinking thereof. While detection systems
have been provided to detect the ignition of such a missile as
quickly as possible, there is only a limited amount of water
available for immediate pumping by the ship's firemains because of
the economics and practicality of keeping a pumping system in
continuous operation for use solely in a fire emergency. With the
sprinkling systems of the prior art the water which was delivered
from the firemains had to be distributed throughout the entire
sprinkler head system in any single magazine even though the
ignited missile and the area immediately adjacent thereto received
only a small fraction of the total water being pumped to the
system. This conventional type of sprinkling system, therefore,
poses a safety problem on naval vessels particularly when the
vessels are carrying missiles which generate large amounts of heat
and flames.
Another problem with the prior art systems is that an inherent
delay occurs before actuation of the sprinkling heads since
conventional heat sensors that were mounted above the missiles were
used to detect the presence of an abnormal amount of heat before
activating the sprinkling heads. Since missiles generally ignite at
the lower ends thereof in their stored position, a serious amount
of damage could already have occurred before a ceiling sensor could
detect the heat generated by the ignited missile.
SUMMARY OF THE INVENTION
The primary objective of the automatic sprinkling system of the
present invention is to provide for zoned sprinkling wherein, upon
the detection of a fire, all of the available water in the pumping
system is delivered to the area of the fire and the area
immediately adjacent thereto. In the case of missiles aboard a
naval vessel, this means that sprinkling will be provided only to
the ignited or burning missile and to the adjacent missiles in the
missile containing magazine. This sprinkling zone is always
centered upon the location of the fire regardless of where the fire
is located throughout the area of the automatic sprinkling system.
Furthermore, the entire output from the firemains can be directed
to the critical zone until and unless another fire is detected so
as to expand or split the sprinkling zone accordingly.
A particular feature of the present invention is the nature of the
hydraulic control system which is utilized for providing a true
zoned sprinkling effect regardless of where the initial fire is
located within the area of the system. A sprinkler head, or heads,
are provided at predetermined locations throughout the area of the
sprinkling system as with conventional automatic sprinkling
systems. Where the sprinkling area includes a plurality of highly
combustible objects set at predetermined locations, such as
ignitable missiles in a magazine, the sprinkler heads would
obviously be located so as to direct the water from the sprinkling
heads upon such objects. Each sprinkling head is provided with
water at a predetermined pressure with the flow from the head being
monitored by a differential control valve. Sensing means are
provided with each sprinkling head to sense the presence of a fire
in the area adjacent to the sprinkling head, and the sensing means
are hydraulically connected to the associated control valve so as
to open the valve and allow water therethrough to the sprinkling
head. Each of the control valves are interconnected by a series of
control lines and check valves which form the hydraulic control
system whereby, upon the actuation of any one control valve, the
control valves of the adjacent sprinkler heads will also be
actuated while the remainder of the system is unaffected.
Another special feature of the invention is the means for detecting
the presence of a fire when the sprinkling area includes a
plurality of combustible objects such as ballistic missiles or the
like which eject flames from the lowermost ends thereof. A plate is
provided at the bottom of each missile which plate is arranged to
be moved downwardly under the pressure of the flames or expanding
gases ejected by the missile and, in so doing, depressurizes a
control line which triggers the control valve that operates the
sprinkler head providing water to the ignited missile. This event
automatically actuates the control valves for the sprinkler heads
located above the adjacent missiles also. Thus, the zoned
sprinkling effect is provided at the earliest possible time before
the heat from the ignited missile has had a chance to ignite other
missiles within the area of the sprinkling system.
With the sprinkling system of the present invention all of the
available pumping capacity is directed almost immediately to the
area where it can do the most good. Even if the fire rapidly
spreads, the adjacent areas will come under sprinkling as the fire
detection means associated therewith are actuated, and hopefully,
additional pumping capacity will be available by this time to
handle the additional quantities of water needed .
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of the hydraulic circuitry for
the automatic sprinkling system of the present invention.
FIG. 2 is an enlarged schematic illustration of a portion of the
sprinkling system shown in FIG. 1.
FIG. 3 is a schematic illustration of the supply and external
control means for the automatic sprinkling system shown in FIG.
1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The automatic sprinkling system of the present invention, the
hydraulic circuitry of which is shown schematically in FIG. 1, is
particularly designed for the automatic sprinkling of ballistic
missiles such as those within a magazine aboard a naval vessel for
example. It will be recognized, however, that the system to be
described can be used for many other specific purposes particularly
where a plurality of highly combustible objects are provided at
spaced locations within the area of the sprinkling system and fast
delivery of maximum amounts of water, of other quenching fluids, to
the initial location of the fire is required. In the system shown,
the objects to be protected include 24 missiles, numbered M1
through M24, arranged in two groups comprising closed loops of 12
missiles each which are indicated (in FIG. 1) as Group A and Group
B. It will be noted that the missile groups are located in
juxtaposition so that five of the missiles of one group are located
closely adjacent to five missiles in the adjacent group. Each of
the missiles is provided with a pair of overlying sprinkler heads
12 (FIG. 2) which are coupled together and which are provided with
water upon the actuation of a control valve which is operatively
connected to the heads to monitor water thereto. One control valve
is provided for each missile, and the control valves have been
numbered V1 through V24 in the drawings so that that numbering of
the control valves directly corresponds to the numbering of the
missiles, as shown in FIG. 1. All of the control valves in each
group are interconnected by a water supply line L1A or L1B which
supplies water to the sprinkler heads 12 upon actuation of one or
more sets of control valves; that is to say, control valves V1-V12
of Group A are interconnected by the water supply line L1A, and
control valves V13-V24 of Group B are connected by the supply line
L1B.
Each of the control valves V1-V24 is a differential type valve
which uses the hydraulic pressure in a control line to close off
the water supply to the sprinkler heads 12. Control line pressure
for all of the control valves is supplied through three separate
control lines in the sprinkling system for each group of missiles
including lines L2A, L3A and L4A in the system for missile Group A
and including lines L2B, L3B and L4B in the system for missile
Group B. As will be recognized from FIG. 1, the control lines L2A
and L2B provide a uniform control pressure to each of the control
valves in the group. These control lines are provided with a
plurality of restricted orifice connections to the individual
control valves the nature and purpose of which will be explained
presently. The control lines L3A and L4A (and corresponding lines
L3B and L4B), on the other hand, also interconnect the control
valves of each group, but these lines are provided with a plurality
of interposed check valves for controlling the flow of supply water
to particular control valves in the group only; the operation of
such check valves to be explained in more detail hereinafter. A
continuous water supply line L5, which is entirely separate from
the supply lines L1A and L1B, extends beneath each of the missiles
in each group to selectively provide a supply of quenching water to
the lowermost ends of the missiles in a manner to be explained in
greater detail hereinafter.
Referring further to FIG. 1, the sprinkling system of the present
invention is operated so that, upon actuation of the fire condition
sensing means associated with any missile M1-M24, the control valve
for actuating the sprinkling heads 12 above that missile and the
control valves for actuating the sprinkling heads above the
adjacent missiles will be activated while the remainder of the
sprinkling system is unactivated, and this means that all of the
available water in the supply lines L1A or L1B will be directed to
the area of the fire condition where damage is most likely to occur
first and from where the fire will spread. For example, if the fire
condition sensing means associated with missile M1 were to be
actuated, the control valves V1, V2 and V12 would be operated so as
to supply all of the available water to the missiles M1, M2 and
M12, respectively. If the fire condition sensing means associated
with the missile M2 were to be activated, the control valves V2, V3
and V1 would be actuated so as to supply all of the available water
to the missiles M2, M3 and M1, respectively. When the fire
condition sensing means which is actuated is in the area where the
two missile groups are adjacent to each other a greater area must
be supplied with sprinkling since there will be more missiles to be
covered. For example, if the fire condition sensing means
associated with missile M5 were to be actuated the control valve V5
would be actuated in turn to supply water to missile M5, and each
of the adjacent control valves V4, V6, V13, V14 and V24 would be
actuated to supply water to the missiles M4, M6, M13, M14 and M24,
respectively. If the fire condition sensing means associated with
the missile M8 were actuated, the control valve V8 would be
actuated in turn to supply water to missile M8, and the adjacent
control valves V7, V9, V22, V21 and V23 would be actuated to supply
water to the adjacent missiles M7, M9, M22, M21 and M23,
respectively. Finally, the actuation of the fire condition sensing
means associated with the missiles at the ends of the group would
actuate only the control valves for the directly adjacent missiles;
for example, if the fire condition sensing means associated with
control valve V21 were actuated it would actuate control valves
V20, V21 and V22.
The water supply to the lowermost portion of the missiles through
line L5 is not a direct part of the zone sprinkling system since
the zone concept applies only to the sprinkling heads 12 which
overlie the missiles. Water which is delivered from line L5 to the
missiles will be provided upon the blowing out of a pressure plate
at the bottom of each missile that is ignited by the direct
injection of water into the ignited missile all in a manner to be
further explained hereinafter.
The hydraulic circuitry components and their mode of operation for
obtaining a true zoned sprinkling system can be best shown with
particular reference to FIG. 2 which illustrates, in enlarged
schematic detail, missiles M1, M2 and M3 and the sprinkling system
circuitry associated therewith. Each differential control valve V1,
V2 or V3 is provided with a pressurized control line 20 which keeps
the associated control valve closed against the pressure of the
water in the supply line L1A acting through the individual supply
lines 22 to the control valves. Each control line 20 is in direct
communication with a main triggering check valve 24 which is set so
as to maintain the water in the line 20 at the predetermined
control pressure to keep the associated control valve V1-V3 closed.
The blocking side of the triggering check valve 24 is connected to
a line 26 which extends to an enclosed chamber 27 adjacent the base
of the missile which chamber is closed by a removable valve plug 28
to maintain the pressure in line 26. The valve plug 28 rests upon a
plate 30 which is secured by a thin annular lip 31 atop of an
annular ledge of an upright injector nozzle structure 32. The
injector nozzle structure is provided with a continuous supply of
water from the supply line L5 which, in the system of the present
invention, is supplied from means capable of delivering a
sufficient quantity of water to be directed into the cone portion
of an ignited missile, so as to thoroughly quench this area of the
missile.
The injector nozzle structure 32 will be seen to comprise an outer
sleeve 34 which is mounted in a fixed position in communication
with the supply line L5 and an inner tubular section 35 which is
adapted to slide longitudinally within the sleeve. The top of
tubular section 35 includes a removable plug 35a which is adapted
to be blown off when the nozzle is actuated as will be explained in
greater detail hereinafter. In the inoperative position of the
injector nozzle shown in FIG. 2, the interior tubular section 35 of
the nozzle is held in a lowered position by a plurality of
retaining balls 36 which are carried by the sleeve 34 and are
wedged into an annular groove 37 in the plug 35a at the top of the
tubular section 35 of the nozzle.
When a missile is ignited, the pressure caused by the flames or the
expanding gases acting against the plate 30 will cause the thin
annular flange 31 to shear off thereby dropping the plate within an
enclosed plenum chamber 40 which extends beneath all of the
missiles of each group. This frees the retaining balls 36 which
drop out of the nozzle sleeve 34 and allow the inner tubular
section 35 to rise under the pressure of the water in line L5 until
an annular flange 38 on the tubular section abuts against the body
of the fixed sleeve 34. The plug 35a, which is freed from the
retaining balls 36, will be ejected so that water from the supply
line L5 will be directed into the interior of the missile.
The actuation of the pressure plate 30 also sets the overhead zone
sprinkling system into operation which operation will now be
described with particular reference to the ignition of the missile
designated M2 (FIG. 2). With the release of the plate 30 the valve
plug 28, which is resting upon the plate, will drop out so as to
relieve the pressure on the associated triggering check valve 24
through control line 26. This has the effect of opening the control
valve V2 to the flow of supply water since the control pressure in
line 20 will be relieved through the now opened triggering valve
24. It will be noted that control line L3A is in communication with
the relieved control line 26 through a pair of check valves 42 and
44 and that the removal of pressure in line 26 will open both of
these check valves. It will further be noted that this places line
26, which is open to the atmosphere, in direct communication with
the pressure control lines 20 to each of the adjacent control
valves V1 and V3 so that these control valves will also be actuated
when the control valve V2 is actuated. However, since the
triggering check valves 24 for each of the control valves V1 and V3
will not be actuated, the control valves adjacent to control valves
V1 and V3 (other than control valve V2) will not be actuated. It
will further be noted that the pressure control line 20 for control
valve V2 is in direct communication through control line L4A with a
second pair of check valves 46 and 48 which are in communication
with the hydraulic control circuitry for the adjacent control
valves V1 and V3 respectively; however, these check valves are
oppositely positioned from the check valves 42 and 44 so that the
relief of pressure in the line 20 will not open them.
The hydraulic control circuitry for each of the control valves V1
and V3 is precisely the same (with one exception) as the
aforedescribed circuitry for control valve V2 and, therefore, will
not be described in detail. These valves are operated in exactly
the same way as V2. For example, if pressure is relieved in the
line 26 which is associated with the control valve V3 then the
control valve V3 will be opened as its associated pressure control
line 20 is drained, and the adjacent control valve V2 will also be
opened since the check valve 48 will now open to depressurize line
20 to valve V2. A similar check valve 50 is provided in line L4A to
relieve the control pressure line for the adjacent control valve V4
(not shown in FIG. 2).
The only distinction between the hydraulic control circuitry for
valve V2 and that for valves V1 and V3 is that the circuitry for
the latter valves includes a sensor 55 which is adapted to be
actuated by heat at the top of the missile rather than by the heat
or pressure at the bottom of the missile. These sensors, which are
conventional, include a fusible plug valve which opens when
subjected to heat and relieves the pressure in a hydraulic line 56
that is connected thereto. The loss of pressure in line 56 relieves
pressure on the triggering check valve 24 to thereby actuate the
control valve associated therewith and the adjacent control valves
all as described hereinbefore.
In the case of the actuation of those control valves V4-V8, V13,
V14 and V22-V24, which are associated with missiles that are in the
central area of the magazine where the two groups of missiles are
adjacent to each other, activation of one of the aforedescribed
sensing means 28 or 55 associated with a missile of one group not
only actuates the sprinkling systems for one adjacent missiles in
that group but also, through connecting lines 58 (FIG. 1),
activates the triggering check valves 24 associated with the
control systems for the adjacent missile in the other group of
missiles. Thus, as many as six separate missiles can be provided
with water upon the detection of a fire in any one of them.
The supply and external control means for the circuitry of the
present invention is particularly shown in FIG. 3. In order to
prevent corrosion in the valves and other operating components of
the hydraulic circuitry, fresh water is provided throughout the
control circuitry of the present invention even though contaminated
water, such as sea water, will be pumped through the supply lines
and sprinkler heads during a fire. The fresh water which is in the
system during its "ready" state is controlled by an accumulator
control tank 60 which is filled with a sufficient quantity of water
to permit operation of the system and is charged with air or an
inert gas through a check valve 62 so that the pressure in the tank
(and throughout the control system) is maintained at a
predetermined level; for this purpose, the tank may be provided
with a conventional relief valve 63 and a bleeder valve 64.
Indicating devices such as pressure switch 65 and pressure gauge 66
can also be provided so that the control system pressure can be
readily checked. A gauge 67 is provided alongside the tank to
indicate that the correct amount of water is present in the
tank.
The control tank 60 is placed in communication with the control
circuitry for all of the control valves V1-V24 through an outlet
line 69 which includes therein a manual shutoff valve 70, a check
valve 72, and a second shutoff valve 74. Line 69 is in
communication with one side of a normally-closed pressure-operated
valve 75 which, when closed, diverts flow from line 69 to a line 76
and into the control line L2A that is in communication with each of
the control valves V1-V12. A secondary line 76a branches from the
line 76 to supply control pressure to the line L2B which is in
communication with the control valves V13-V24. The accumulator
control tank is also in communication with the supply line L1A (and
L1B) through line 78 (and 78a) which branches from line 69 and
includes therein a shut-off valve 80 and a filter 82. This latter
connection is necessary since the control system will loose
pressure during the actuation of one or more sets of control
valves, and it is desired that the control pressure never drop
below the supply pressure so that the entire sprinkling head system
will not be activated.
The water necessary for supplying the main supply lines L1A and L1B
comes from the firemains through a manually operated shutoff valve
90, a filter 92, and a normally-open pressure-operated valve 94.
This sea water supply is then branched into two secondary supply
lines 95 and 95a serving the supply lines L1A and L1B,
respectively. Each of lines 95 and 95a has therein a check valve 96
which separates the control side of the circuitry from the supply
side. That is to say, when the automatic control system is set, the
control side is at a significantly higher pressure than the sea
water supply side so that all of the hydraulic control circuitry
and the circuitry and components in the supply portion of the
circuitry downstream from the check valve 96 will be normally
supplied with fresh water in order to prevent corrosion. When one
of he sprinkler heads is actuated and water is supplied from one of
the supply lines L1A or L1B, the pressure on the control side will
rapidly drop until it equals the sea water supply pressure at which
time the appropriate check valve 96 will open and sea water will be
directed into the supply line to keep the system in operation. By
way of example, the control side may be set at a pressure of about
225 psi when there is a normal sea water supply at a pressure of
about 150 psi.
It will be noted from FIG. 2 that each of the control lines 20,
which relieve the pressure on the associated control valves V1, V2
or V3, has therein a restricted orifice 100 which provides
communication between the line 20 and a line 101 that is in
communication with the control line L2A. The orifices 100 are used
in the recharging of the system, and they are restricted so that
the control pressure will not drop too rapidly before it can be
equalized with he supply pressure. Each of the other control valves
in the system is, of course, provided with similar restricted
orifice connections as shown in FIG. 1.
Manual control of the sprinkling system is provided by a control
valve assembly 110 which includes a valve member 111 which is
movable into three positions designated (in FIG. 3) as "start,"
"automatic," and "stop." During normal system operation, wherein
all of the sprinkler heads are charged and ready to supply water
upon actuation of their respective control valves, the control
valve assembly 110 will be in the neutral or "automatic" position.
By rotating the valve element 111 to the "start" position,
communication is provided between the control line 69 and the
pressure side of valve 75 through check valve 112 so as to open
valve 75 and allow the control pressure in lines 76 and 76a to flow
through valve 75 to a drain. Upon the release of the control
pressure from lines 76 and 76a, all of the control valves V1-V24
will be actuated and all of the sprinkler heads 12 will
consequently be turned on.
When it is desired to stop the sprinkling system, or to lock it
out, the valve member 111 of the control valve assembly 110 is
moved into the "stop" position wherein water from the control tank
is diverted from the line 69 through the control valve assembly 110
to the pressure side of the pressure-operated valve 94 so as to
close this valve and prevent the water from flowing into the system
from the firemains. It will be noted that restricted orifices 120
are provided in each of the lines connected to the "start" and
"stop" sides of the valve assembly 110 to provide communication
between these lines and a drain. These restricted orifices allow
leakage from these lines in case there is leakage from the control
circuitry through the control valve assembly 110 so that the
pressure-operated valves 75 and 94 will not be actuated
inadvertently.
The moving of the control valve assembly 110 into the "stop"
position is, generally speaking, the first step in the recharging
or resetting of the automatic sprinkling system after it has been
in operation due to a fire or other cause. As pointed out
hereinbefore, this action results in the closing of the
pressure-operated valve 94 to block the firemains. Alternatively,
the manual control valve 90 can be closed. The next step in
recharging the system (assuming by way of example that only certain
of the sprinkler heads associated with the missiles of Group A were
actuated) is to first drain the sea water from both the supply line
L1A and the control circuitry through the control line L2A. Lines
L1A and L2A are drained through the manually operated drain valves
130 and 132, respectively (FIG. 3). A similar draining system is
provided for the supply line L1B and the control circuitry
associated with control line L2B, as shown in FIG. 1. Next, the
inlet supply line 95 and the check valve 96 therein are cleared of
sea water through the manually operated drain valve 134. All of the
control circuitry and supply circuitry of the automatic sprinkling
system of the present invention should now be free of the sea water
which came into the system from the firemains during actuation of
one or more of the sprinkler head control valves.
The next step in the recharging procedure is to supply all of the
circuitry which was just drained with fresh water from a separate
fresh water supply source. In order to supply fresh water to the
control side of the circuitry one of end of a detachable hose 140
is connected to a manually operated shutoff valve 142 that is in
communication with a fresh water supply line. The other end of the
hose 140 is connected to a manually operated shutoff valve 144
which directs the fresh water through a filter 146 into the control
line 69. This supplies water through line 76 to control line L2A
which directs the water through the restricted orifices 100 to the
control circuitry for each of the control valves so as to reset
these valves. Next, a pair of flexible hoses 136 are connected
between manually operated shutoff valves 137 and 138 which are
connected to the fresh water supply line and to the inlet supply
line 95, respectively. By this means, fresh water is supplied to
the line L1A and up to each of the control valves associated with
each of the sprinkler heads. Once the system has been completely
recharged with fresh water, the shutoff valves 137, 138, 142 and
144 are closed and the hoses 136 and 140 can be detached. The
system is then reset ready for actuation when one of the sensing
means 55 or 28 associated with one of the missiles M1-M24 actuates
the associated sprinkling head control valve in the manner
aforedescribed.
With the automatic sprinkling system of the present invention it
will be recognized that a true zoned sprinkling system is provided
that will direct water from an overhead sprinkling system to the
area where a fire is started and to the immediately adjacent areas
where the fire is most likely to spread while the remainder of the
sprinkler heads in the sprinkling system remain inactive. In this
way, the total available water is directed to the area where it
will do the most good and it will be noted that the spray area, or
zone, will change in accordance with the location of the fire
condition sensor that is activated. It will further be recognized
that a means is provided for supplying large quantities of water
immediately at the base of a combustible object such as a missile
by means of a very rapidly actuated and pre-charged injection
nozzle so that critical time is not lost in allowing for the heat
of the ignition object to rise to actuate a conventional overhead
sensor.
Although the best mode contemplated for carrying out the present
invention has been herein shown and described, it will be apparent
that modifications and variations may be made without departing
from what is regarded to be the subject matter of the
invention.
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