Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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!,'' The present invention relates to a container constructed for per-
mitting rapid filling as well as discharging; more particularly, but not
exclusively, the present invention relates to the transportation of water by
means of aircraft to be used for fighting fire.
Aircrafts have been used as fire fighting equipment, whereby, for
example, a helicopter is provided with a container to be filled rapidly from
the water of a lake, a river, or the like, being as close as possible, for ex-
. ample, to a forest or bush fire. The helicopter then dumps that water upon
the fire. Obviously, filling and emptying has to be carried out as fast as
possible to permit as many round trips of the aircraft as it can possibly
make (without refueling) to speed up the extinguishing of the fire.
It is an object of the present invention to provide a new andimproved container for the transport of a liquid medium permitting rapid
charge and discharge when needed.
The invention provides a container for rapid action filling and
discharge, comprising: a bottom plate; a rod centrally affixed to said
plate; a hollow drum being open at top and bottom and disposed for being
seated onto said bottom plate; guide means extending inwardly from said drum
for coaxially positioning and slidingly receiving said rod; a load bearing
cable affixed to saicl rod for suspending the rod, the bottom plate as well
as said drum when seated upon said bottom plate; sealing means for effecting
a seal between a bottom rim of said drum and said bottom plate when said drum
is seated on said bottom plate; and hydraulic means connected to said drum
for lowering said drum onto said bottom plate and for lifting said drum off
said bottom plate, independently from lowering and lifting of the bottom
plate by means of said cable.
It can thus be seen that the container provided in accordance with
the preferred embodiment of the invention, permits rapid opening and closing
through raising and lowering of the drum. The bottom plate, through the
central rod, is suspended from a helicopter and is as such lowered onto and
into a water re~ervoir while the container is opened through raising the
drum, permitting the plate to drop into the reservoir about as deep as the
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drum is high. The container, therefore, will fill at the rate of descent of
the bottom plate into the water. Having filled the container in that manner,
the drum is placed back onto the container, and the entire assembly is lifted
off out of the reservoir. Whenever discharge of the water is needed and des-
ired, the drum is simply lifted, the rate of lifting as well as the width of
the gap formed, determining the rate of outflow of the container contents.
Specifically, rapid lifting of the drum for opening a fairly wide gap will
almost instantaneously empty the entire container onto the location under-
neath, dumping, for example, several cubic meters in a second. The container
is particularly suited for transport, filling and discharge, while being
suspended from a helicopter, because hovering permits vertical descent for
filling, as well as for controlled dumping. The container should be suspended
from near or right at the center of gravity of the helicopter, so that load
changes do not interfere with the crafts stability. The bottom plate may be
constructed so that the water is discharged in individual turbulent jets for
the generation of foam.
While the specification concludes with claims particularly pointing
out and distinctly c].aiming the sub~ect matter which 1~ regarded as the
invention, it is beli.eved that the invention, the ob~ects and features of the
invention, and further objects, features and advantages thereof will be better
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understood from the following description taken in connection with the accom-
panying drawings in which:- :
Figure 1 is a cross-section through a container being closed and con-
structed in accordance with the preferred embodiment of the present invention;
Figure 2 shows the same container of Figure 1 but in side elevation
and in the open state;
Figure 3 is a top view of the container shown in Figures 1 and 2;
Figure 4 illustrates a modified detail of the container shown in
Figures 1 through 3 and relating particularly to an aspect of sealing;
Figure 5 illustrates a modified example of the preferred embodiment
of the present invention, also shown in cross-section;
Figures 6a and 6b are diagrams of a hydraulic circuit operating the
container shown in Figure S;
Figure 7 shows a modified container as compared with Figure 5;
Figure 8 illustrates an electrical hydraulic circuit of the container
shown in Figure 7;
Figure 8a shows the hydraulic part of the circuit of Figure 8 in a
different operating state;
Figure 9 is a side elevation of a modification applicable to any of
the containers shown in the preceding Figures; and
Figure 10 illustrates an enlarged detail of the containers of Figure
9.
Proceeding now to the detailed description of the drawings, Figures 1,
2 and 3 illustrate a transport container being comprised essentially of a cyl-
indrical vertical sleeve or drum 1 being per se open at top and bottom, but the
open bottom is closed by means of a bottom plate 2. The drum 1 is provided in
addition with two centering devices 4 and 5, each of them including spider-like
arms, such as 4a and 5a and each having one end attached to the inner surface
of the drum 1. The arms 4a carry a short bushing or sleeve 4b; arms 5a carry
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bushing segments Sb which together can be deemed to define a bushing or sleeve.
These two bushings 4b and Sb are axially aligned to each other, and
they are positioned coaxially to the center axis of the drum 1. These bushings
receive in sliding engagement a rod or post 3 to which the bottom plate 2 is
affixed. Therefore, the rod 3 together with plate 2 can slide up and down in
a concentric relation to the axis of drum 1, whereby of course, the lower rim
or edge of the drum 1 serves as a stop for the plate 2 and upon abuttment the
container is closed from the bottom. The container is otherwise open at the
top, the arms 4a are merely provided for centering the bushing of 4b and do
not close the container from above.
One of these arms 4a is provided with an eye 10 to which is affixed
a rope or cable 8. The top of rod 3 has or is formed into an eye 9 receiving
a hook at the end of a rope or cable 7. Rope or cable 7 is affixed to a heli-
copter or the like, since 7 is a load carrying cable it should be affixed to
the center of gravity of the helicopter so that varying load conditions do not
interfere with the stability of that craft. The other end of rope 8 is wound
onto and affixed to a winch on board of the helicopter to permit pulling of
the rope 8 or lowering if independently from cable 7. The drum 1 is suspended
by rope 8 (Figure 2) or can sit on bottom plate 2 in which rope 8 is slack
tFigure 1).
The bottom rim of drum 1 is provided with a sealing lip 6 which may
be hollow and will be squeezed when the drum 1 sits on the bottom plate 2. The
lip 6 extends into the interior of the drum. When the container is filled
with water, the hydrostatic pressure forces this lip 6 into the corner portion
of bottom plate and the wall of drum 1 to obtain the desired and required
sealing effect.
Figure 2, as stated, shows the particular container in the open
state, drum 1 being lifted from bottom plate 2 to open a gap 11 between them.
This permits discharge of the content of the container or, upon submerging of
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these parts, fluid may then enter the interior of the drum.
Before proceeding to the description of the operation of this partic-
ular container, a modification should be described with reference to Figure 4.
This Figure shows in cross-section and on an enlarged scale a detail concern-
ing the sealing between a modified bottom plate 2' and the drum 1. The lower
front end of drum 1 is cut by milling, turning or the like to be a truly plan-
ar annulus. ~n annular recess in this bottom plate 2~ includes likewise a
truly, planar turned annulus 13. These two surfaces 12 and 13 engage when the
drum 1 in fact sits on the bottom plate 2. It was found that the sealing pres-
sure necessary to sustain the static pressure of a filled container is in factprovided to a sufficient degree by the weight of the drum 1.
This particular container is now operated as follows. The container
is suspended from a helicopter whereby, as was stated above, cable 7 suspends
the container as a whole from an anchoring point near or in the center of grav-
ity of the helicopter. The cable 8, as far as its helicopter side end is con-
cerned, is wound on a winch, but is slack as drum 1 should not be lifted when
the container is to be closed. Following the dumping of the content of the
container, drum 1 remains off the bottom plate 2. The helicopter now flies to -;
a suitable reservoir and, for example, descends towards the water surface. The
bottom 2 will be submerged first followed shortly by the drum 1 spaced from
the plate 2 by gap 11. Accordingly, the container is filled just about at the
rate of descent.
Following this very rapid filling the drum 1 is lowered through the
cable 8 until it rests on the bottom 2 while the helicopter hovers. As the
cable 8 slackens the container is in fact closed, and the parts 1 and 2 are
sealed in relation to each other, with or without the aid of the static pres-
sure of the water that fills the container, which however, is at that point,
not effective but becomes effective as the closed container is lifted through
ascent of the helicopter. It should be mentioned that cable 7 could also be
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winch operated so that the helicopter hovers while parts 1 and 2 are submerged,
closed and lifted again, but the latter is more conveniently carried out by
ascent of the helicopter itself.
Now the helicopter flies to the fire site and the winch for rope 8
lifts the drum rapidly to dump the entire water content as fast as possible
upon the fire, depending upon the rate of lifting of the drum 1 from the
bottom 2 under the drum. By way of example, a five to seven cubicmeter con-
tainer can be dischargedcompletely within 1 to 3 seconds. It should be men-
tioned~ however, that the rate of discharge is in effect controlled not only
by the speed of lifting the drum 1 from the bottom 2, but also by the width of
the gap 11 permitted to open. This way, a rather accurate control is provided
as to the rate of discharge of the water, which may be of importance to the
economic and efficient use of the water at the fire site.
In the embodiment above, the particular operating mechanism for open-
ing and closing the container is strictly a mechanical device with mechanical
actuation occuring in the hel;copter, namely, movement of the cable or rope 8
relative to the cable 7 for raising and lowering the drum 1 in relation to the
bottom plate 2. In the example shown in Figure 5, a drum 21 is raised and low-
ered in relation to a bottom plate 22 by hydraulic means. The basic container
construction is the same as in the previously described example: there is a
pair of glide sleeves or bushings 24 and 25 for centering a post or rod 23, the
latter being affixed to the bottom plate 22.
The centering sleeve or bushing 25 is held by plurality of spider
arms in coaxial relation and by affixation to the drum 21. The upper sleeve 24
is fixed to a top of the container which, however, has azimuthally arranged
openings as well as a central opening in which has been positioned the bushing
24. The rod or post 23 has an eye 20 on its top, gripping a hook, eye, or the
like at the end of the cable 7. The cable 7 is, of course, a load bearing
cable for the container in effect suspending the bottom 22 from the helicopter.
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In order to operate the container for opening and closing, and par-
ticularly for lowering or raising the drum 21 in relation to the bottom plate
22, there is provided a pneumatic drive 14 being a bi-directional pneumatic
drive. The drive 14 is held on the post 23 by means of clamps 17. This way,
the cylinder portion of the drive is affixed to the assembly 22, 23. The
drive has a piston 15a ¦see Figures 6a, 6b) and a piston rod 15 projecting out
of the cylinder of the drive. The piston rod 15 is hinged by means of a
hinge or a pivot joint 16 to the top of the container 21, but on the inside
thereof.
It should be noted that an eye 10 is also provided here on the top
of the drum 21; one may affix a trigger rope such as 8 to the eye 10 as an
alternative means for raising and lowering the drum 21 in relation to the
bottom plate 22. This may be a safety feature permitting, for example, emptying
the container in an emergency situation if the hydraulic drive malfunctions.
The two sides of the piston 15a, i.e., the two piston chambers in
the drive 14 on opposite sides of the piston 15a are fluid conductively con-
nected to hoses 18 and 19 which operate alternatingly as venting and pressur-
izing ducts. These hoses run along the cable 7 and may be held or clamped or
otherwise affixed in relation thereto, and they terminate in suitable hydrau-
lic equipment in the helicopter.
In addition to the raising and lowering of the drum 21 this pneuma-
tic drive 14 may,in effect, continue to provide a force that forces the drum
21 towards and against the bottom 22, thereby reinforcing the sealing. Thus,
the sealing in this case will not be exclusively a~fected by the weight of the
drum 21.
Figures 6a and 6b illustrate the pneumatic circuit for the drive 14
showing in addition schematically a control valve 20 being onboard of the heli-
copter, right at the cockpit, and cooperating with a source of pressure 40,
such as a container filled with pressuri~ed air, a compressor or the like.
The Figures 6a and 6b differ as to the position of the valve 20.
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The valve 20 has two ducts for each of its two operating positions.
In the position shown in Figure 6a, valve 20 connects the pressure source 40
to hose 19 to drive the piston 15a in a manner which causes the piston rod 15
to be retracted, and that is the equivialent of, and in effect causes, lower-
ing the drum 21 onto the bottom 22. In the same operating state, valve 20
connects hose 18 to a venting outlet. Therefore, the weight of drum 21 contri-
butes to its lowering as soon as hose 18 starts venting.
It can be seen that the piston 15a will reach a limit position, i.e.,
a position established by the fact that the piston rod cannot be retracted fur-
ther simply because drum 21 has come to a resting stop on plate 22. In view
of the fact that the connection for the pressure medium is retained thereafter,
the piston 15a is under continuous pneumatic force and that, in fact, urges
the drum 21 onto the plate 22, reinforcing the sealing.
For raising and lifting the drum 21 from the bottom 22, valve 20 is
placed into the alternative position which is shown in Figure 6b. The connec-
tions between the hoses, on one hand, and the pressure source 40 and the vent-
ing outlet on the other hand, are reversed. Accordingly, the hose 18 is now
connected to the source of pressure 40, to drive the piston 15a for protrac-
tion of the piston rod, and that action causes the drum 21 to be lifted off
the bottom plate 22. Simultaneously, hose 19 is connected by valve 20 to the
discharge and venting outlet so that the previously pressurized chamber of the
piston drive is vented, permitting rapid movement of the piston 15a into the
alternative position.
It can be seen that the valve can be simply manually operated by the
pilot during the various passes he makes with the helicopter.
Proceeding now to the description of Figure 7, it should be mentioned
that the container construction is the same as in Figure 5, and for this reason
the elements 21 through 25 and 29 are the same as in Figure 5. Also, there is
a clamp or mounting structure 17, but the particular hydraulic drive 30, thus
held on post 23 is of the variety for only one-sided operation. Accordingly,
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one side of the drive 30, and particularly the piston chamber thereof, to one
side of the piston, is connected to the line 18 which can either be connected
to a venting outlet or to a source of pressure 41 by means of a three-way
valve 31. The other side of drive 30, particularly the cylinder chamber on
the other side of the piston in drive 30 is connected to a pipe l9a which, in
effect, communicates with the exterior, i.e., with the ambient air, to estab-
lish consistently atmospheric pressure on that side of the piston. The flow
of air through that pipe is bi-directional and depends upon the position of the
three-way, two-position valve 31.
Whenever hose or duct 18 is connected to the pressure source 41, the
piston in drive 30 will be pushed up which, in effect, amounts to a lifting of
the container 21 off the bottom 22. In the case the valve 31 connects the hose
18 to the venting outlet, container drum 21 will sink to the bottom onto
bottom plate 22 by the force of gravity, and air will be forced out of the low-
er chamber of drive 30 while the duct 19a permits pressure equalization on top
of the piston.
The source of pressure 41 i9 mounted in a particular compartment 40
of the container drum 21, which compartment contains also the valve 31. The
compartment 42 can be closed by means of a cover or flap 43. Normally, this
compartment will be closed but upon opening it and folding the cover 43 down
into the illustrated position, the cover can also serve as a step for easy
access for interior of the compartment.
In addition to source 41 and valve 31, compartment 42 contains an-
other valve 44 and a connecting to hose 45, ending in a suitable fitting.
This duct or fluid path permits re-charging and refilling the vessel 41 with
pressure medium.
The valve 31, of course, requires remote control. Such control could
be provided by a suitable electric connection, for example, by wires in a
cable running up together with a load cable 7 to the helicopter but then to
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the cockpit, and to a suitable switch for operation by the pilot. An alterna-
tive mode of valve operation envisioned here is a wireless control from ground.
me compartment 42 contains also the necessary receiving and actuating equip-
ment for operating the valve 31.
Figure 8 illustrates the electrical circuit for remote valve opera-
tion. The valve 31 is depicted in Figure 8 in one particular position, namely
in a position in which the hose 18 is connected via the valve 31 to the pressure
source 41. Figure 8a shows the alternative position in which hose 18 is
vented. Now, as far as the electrical control is concerned, the control de-
vice as such includes, for example, a transmitter 46 placed on ground or in the
cockpit of the helicopter and issuing command signals which may be suitably
encoded, i.e., there is a carrier wave modulated with suitable code signals
for purposes of operating the valve 31. The signals are received by receiver
47 which amplifies the signal to a more suitable level, and feeds its output
to a demodulator 48 which extracts from the signal received the appropriate
valve command.
By way of e~mple, one may use two different modulator frequencies
for frequency modulating the carrier wave in transmitter 46, one modulator
frequency for setting the valve 31 to one position, the other modulator fre-
quency for setting the valve to the other position. The circuit 48 includesnot only a demodulator but also a discriminator (suitable band pass) to detect
whether or not the carrier wave received is modulated with the one or with the
other or with none of these frequencies; in one case a command signal issues
from the circuit 48 causing the valve 31 to be placed in one position, and a
different modulator signal when detected will cause the valve 31 to be placed
in the opposite position.
The electronic circuitry is, of course, contained in the compartment
42, as stated, and it will be necessary to include in the compartment 42 a
suitable battery 49 or the like which provides the system with the requisite
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electrical energy, not only for operating the receiver and demodulator which
requires little power, but electrical energy of a significantly larger magni-
tude is required to operate the magnet, solenoid-type valve 31.
As was mentioned above, the wireless remote control is not a require-
ment in principle for operating this particular type of device~ the valve 31
may also be operated through wires and the control circuit is directly on-
board of the helicopter, and command signals are run down alongside of cable
7. In that case, one may still need a power source for operating valve 31.
Conceivably, this power could be derived from the onboard equipment, but it
was found to be of advantage to include the battery 49 in the container equip-
ment, as a local power source for operation of valve 31. Now, one will need
only connections from the cockpit to the container for providing mere control
signals for the operation of the valve and not operating power.
It can thus be seen that, when the control circuit of any configura-
tion has placed valve 31 into the position shown in Figure 8, the pneumatic
power from source 41 i9 applied to the hose 18 and drives the piston in the
pneumatic drive circuit up, thereby lifting the container 21 off the bottom
plate 22; this operation will occur for the purposes of charging or discharg-
ing the container. By suitable command, as outlined above, the valve 31 can
be placed into the opposite position as shown in Figure 8a. In this case, oon-
tainer 21 will drop to its bottom plate 22, the drive 30 being in effect vent-
ed on all sides of its piston.
Figure 9 now illustrates a modification which is applicable to any
of the types of containers and operating mechanisms described earlier. This
particular container has a drum 51 and a bottom 52. The container is provided
in addition with structure that permits the development of fire extinguishing
foam. First of all, the container will include a separate compartment for
foaming substances. In addition the particular bottom 52 of the container is
skirted by a metal or plastic strip 32. This strip 32 has its upper edge pro-
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jecting beyond the upper sealing border of container bottom 52, so that a kind
of fence is formed around the bottom plate 52. The upper part of strip 32 has
semi-circular notches 33.
Reference numeral 11 in Figure 10 denotes again the gap being opened
when the drum 51 is lifted off plate 52. In this particular environment, this
gap has the added connotation of defining nozzle openings upon lifting the
container drum 51 off the bottom part 52. One can readily see that the device
is constructed so that the drum 51 should not be lifted higher than the width
of strip 32 whereby in particular the bottom edge of drum 51 remains below the
upper edge of that strip. This way, a plurality of exit nozzles are estab-
lished, and the water will emerge in individual jets. The jets are formed
following the emergence flow of the water from underneath the lifted drum 51,
so that more or less free turbulent jets are established which inherently mix
intensively with the air in the environment and that establishes the desired
foam.
The notches in the strip 32 defining these nozzle openings may have
a different contour, also their spacing may differ depending upon whether
larger or smaller fanning is desired.
It can, thus, be seen that the various containers as described above
have quite a number of similar features but differ in certain details. H~w-
ever, in all instances, there is a drum which is being lifted mechanically off
a bcttom plate, the bottom plate being held centrally by means of a suspended
post or rod. The drum is being lowered onto or lifted off the bottom plate
either by means of an additional rope or pneumatically whereby additional
sealing can be provided. The source of pneumatic power may be derived from
the helicopter, or locally as far as the container itself is concerned. The
; operation of the valves needed for control of the pneumatic drive can be
carried out locally or remotely. In addition, the bottom can be configured to r
establish conditions for generating foam on discharge of the content of the
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container. Foam generation may be advisable for fighting particular fires.
Decisive in aIl instances is a very rapid mode of openi~g and closing of the
container for obtaining a very high rate of filling and rapid or, possibly,
controlled rather slow discharge of the container content.
The invention is not limited to the embodiments described above but
all changes and modifications thereof not constituting departures from the
spirit and scope of the invention are intended to be included.
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