EP0170453A1

EP0170453A1 - Improvements relating to inflation arrangements for air balloons or the like

Info

Publication number: EP0170453A1
Application number: EP85304942A
Authority: EP
Inventors: Denis Victor Butler
Original assignee: Plessey Overseas Ltd
Current assignee: Plessey Overseas Ltd
Priority date: 1984-07-11
Filing date: 1985-07-10
Publication date: 1986-02-05

Abstract

An arrangement (1) for the rapid inflation of relatively high-volume air balloons (2) or the like, in which the balloon or the like is inflated by an induced air flow from the surrounding atmosphere by the emission from a preferably circular slit-like orifice (12) of an air mover structure (13) of high pressure air derived from a high pressure low volume air supply vessel (4) connected to the air mover (13).

Description

This invention relates to arrangements for the rapid inflation of relatively high-volume air balloons or the like eminently suitable for deployment as waterborne marker (e.g. radar) balloons or inflatable buoys (e.g. sonobuoys).
Such radar marker balloons may for example be dropped from an aircraft or propelled into the air by rockets and then inflated with air during a parachute descent on to the waters' surface.
According to the present invention in its broadest aspect a relatively high volume balloon or the like may be inflated by an induced air flow from the surrounding atmosphere due to the coanda effect produced by the emission from a preferably circular slit-like orifice of an air mover structure of high pressure air derived from a high pressure low volume air supply vessel connected to the air mover.
According to another aspect of the present invention there is provided an arrangement facilitating the rapid inflation of a relatively high-volume air balloon (e.g. radar marker balloon) or the like for waterborne deployment comprising an elongate relatively low-volume high pressure air supply vessel with outlet nozzle means located at one end thereof, a preferably generally cylindrical air mover structure attached coaxially to the air supply vessel and provided in a web portion thereof with an internal passage-way communicating between the outlet nozzle means and a preferably circular slit orifice of said air mover structure and embodying valve means operable to facilitate the discharge of high-pressure low-volume air from the air supply vessel to said orifice which causes high-volume low-pressure air from the atmosphere in the vicinity of the supply vessel to be induced by the coander effect through the open cylindrical air mover structure and into the balloon which will be secured to the air mover structure, one-way valve means being provided to prevent air escaping from said balloon after the inflation thereof.
In carrying out the present invention, flap valve means may be provided at the mouth of the balloon or the like to allow the induced low-pressure high-volume air to inflate the balloon or the like whilst preventing escape of the air after inflation.
In the deployment of the air balloon or the like, the deflated balloon together with its associated high-pressure air supply vessel and air mover structure and a main parachute may be accommodated within a tubular container which may form part of a rocket for propelling the balloon assembly into the air. The tubular container prevents operation of the aforesaid valve means until such time as the assembly becomes detached from the container in response to the release of a drogue parachute after which the assembly will descend to the water's surface under the control of the main parachute whilst the balloon is being inflated with air.
It will be understood that the balloon assembly within the tubular container may alternatively be dropped front an aircraft (e.g.helicopter) by releasing the assembly from the container. When release of the assembly takes place inflation of the balloon is commenced so that it is inflated before it reaches the water's surface.
By way of example the present invention will now be described with reference to the accompanying drawings in which:

Figure 1 is a diagrammatic interior view of a marker buoy deployment rocket embodying an inflatable marker buoy assembly having an inflation arrangement according to the invention;
Figure 2 shows a fragmentary enlarged partially broken side view of the air mover structure of the marker buoy assembly as shown in Figure 1;
Figure 3 is an end view of the air mover structure taken in the direction A of Figure 2;
Figure 4 shows the sequence of steps involved in the deployment by the rocket of Figure 1 of the inflatable marker buoy embodied therein; and,
Figure 5 shows the sequence of steps involved in the deployment of an inflatable marker buoy similar to that housed within the rocket of Figure 1 by dropping the inflatable buoy assembly from a helicopter.

Referring to Figure 1 of the drawings there is shown a rocket 1 which houses an inflatable marker buoy assembly. The marker buoy assembly comprises an inflatable buoy (or balloon) 2 which may embody a collapsible so-called octal array of trihedral radar signal corner reflectors (not shown) which automatically becomes erected when the buoy is inflated.
The mouth of the inflatable buoy 2 is attached to an air mover structure 3 which can best be seen in Figures 2 and 3. A high-pressure low-volume air supply vessel 4 is arranged to discharge its contents through the air mover structure 3 so as to induce by the coander effect high-volume low-pressure air from the surrounding atmosphere into the buoy 2 for the rapid inflation thereof during deployment of the marker buoy. A flap or other non-return valve 5 is located at the mouth of the buoy 2 so as to prevent the air induced into the buoy from escaping therefrom.
The inflatable buoy also has attached to it at the nosecone end of the rocket 1 a main parachute 6 and a drogue parachute 7. In the deployment of the buoy which will be described later the rocket nosecone will be blown clear of the rocket body by the firing of a charge after a predetermined time from launch of the rocket in order to allow the inflatable buoy assembly to be pulled from the rocket body.
Referring now to Figures 2 and 3 which show the air mover structure 3 in detail, it can be seen that outlet nozzle means 8 of the high-pressure low-volume air supply vessel 4 is connected to a central hollow hub part 9 of the open cylindrical air mover structure 3. This hollow hub part 9 accommodates a displacable piercer pin 10 which due to inertia thereof is effectively displaced rearwardly of the rocket 1 at the launch thereof so that it pierces a diaphragm 11 of the outlet nozzle means 8 in order to allow discharge of the air from the vessel 4 into the air mover structure 3. The hollow hub part 9 communicates with a circular slit orifice 12 in the cylindrical body 13 of the air mover structure 3 through a passageway 14 extending through a radial web portion 15 and embodying a slider valve 16. Until deployment of the assembly is required this slider valve 16 is maintained in a closed condition by the engagement of a spring-loaded slider 17 of the valve with the wall of the rocket 1, as can clearly be seen in Figure 2.
In operation of the buoy inflation arrangement the opening of the slider valve 16 will cause high pressure air from the vessel 4 to pass through the passageway 14 to the narrow slit orifice 12 from which the air will be discharged. This air issuing from the slit orifice 12 will cause a high volume of the surrounding air to be induced by the coanda effect into the mouth of the buoy 2 through the cylindrical cavity provided by the air mover structure 3.
Referring now to Figure 4 of the drawings this shows how an inflatable marker buoy may be deployed by a rocket.
The rocket 1 containing the inflatable buoy assembly as shown in Figure 1 may be launched from a ship 18 after a range fuse arrangement within the rocket nose-cone has been suitably pre-set. As can be seen from the drawing the nosecone 19 of the rocket 1 is blown away from the rocket body and the drogue parachute 7 is deployed consequent upon the firing of a nosecone disruption charge by the range fuse. The deployment of the drogue parachute completely reverses the attitude of the rocket body and causes the inflatable buoy assembly to be pulled from the latter by the drogue parachute 7 as depicted in the drawing.
As the buoy assembly is pulled from the rocket the slider valve 16 (Figure 2) controlling the flow of high pressure air from the air supply vessel 4 to the air mover structure slit orifice 12 will be opened by the displacement of the spring-loaded valve slider 17 so that high pressure air is discharged from the orifice 12 to produce rapid inflation of the buoy in a manner already described with reference to Figures 1, 2 and 3, it being understood that the piercer pin 10 will have pierced the diaphragm 11 at the outlet nozzle means of the air supply vessel at the launch of the rocket. The buoy will thus be inflated as the buoy descends to the water surface under the control of the main parachute 6.
Referring finally to Figure 5 of the drawings which illustrates deployment of an inflatable buoy by a helicopter an inflatable buoy assembly similar to that embodied in the rocket according to Figure 1 but without the parachutes 6 and 7 will be stowed within a tubular container 21 forming part of or mounted within the helicopter 22.
When deployment of the inflatable buoy is required the buoy assembly will be released in any suitable manner from the tubular container 21 but the assembly will remain tethered to the helicopter 22 by Means of a tethering cord 23. The release of the assembly from the container 21 causes the slider valve 16 (Figure 2) to be opened so that air can be discharged from the air supply vessel 4 to the air mover orifice thereby producing rapid inflation of the buoy in the manner already described. The inflated buoy and air vessel 4 may then be dropped from the helicopter 22 by release of the tethering cord 23 for the deployment of the inflated buoy on the water surface.
It will readily be understood that the inflated buoy or balloon could be used for purposes other than radar marking. For example it could be used as a radio transmitting buoy. Whatever the application of the inflation arrangement according to the invention the air mover structur provides for very rapid inflation of high volume balloons from low-volume high-pressure sources and moreover the air vessel conveniently serves as a stabilising keel for maintaining the inflated buoy or balloon in an optimum position for marking or any other purpose.

Claims

1. An arrangement for the rapid inflation of relatively high-volume air balloons or the like, in which the balloon or the like is inflated by an induced air flow from the surrounding atmosphere by the emission from a preferably circular slit-like orifice of an air mover structure of high pressure air derived from a high pressure low volume air supply vessel connected to the air mover.

2. An arrangement for the rapid inflation of a relatively high-volume air balloon or the like for waterborne deployment comprising an elongate relatively low-volume high pressure air supply vessel with outlet nozzle means located at one end thereof, a preferably generally cylindrical air mover structure attached coaxially to the air supply vessel and provided in a web portion thereof with an internal passageway communicating between the outlet nozzle means and a preferably circular slit orifice of said air mover structure and embodying valve means operable to facilitate the discharge of high-pressure low-volume air from the air supply vessel to said orifice which causes high-volume low-pressure air from the atmosphere in the vicinity of the supply vessel to be induced by the coanda effect through the open cylindrical air mover structure and into the balloon which will be secured to the air mover structure, one way valve means being provided to prevent air escaping from said balloon after the inflation thereof.

3. An arrangement as claimed in claim 1 or claim 2, in which flap valve means are provided at the mouth of the balloon or the like to allow the induced low-pressure high-volume air to inflate the balloon or the like whilst preventing escape of the air after inflation.

4. An arrangement as claimed in claim 1 or claim 2 in which for the deployment of the air balloon the deflated balloon together with its associated high-pressure air supply vessel are accommodated within a tubular container forming part of a rocket for propelling the balloon assembly into the air, the tubular container preventing operation of the one-way valve means until the assembly becomes detached from the container in response to the release of a drogue parachute after which the assembly will descend to the water's surface under the control of the main parachute whilst the balloon is being inflated with air.