US3229290A

US3229290A - Releasable balloon decoys

Info

Publication number: US3229290A
Application number: US340935A
Authority: US
Inventors: Evan D Fisher
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-03-06
Filing date: 1953-03-06
Publication date: 1966-01-11
Anticipated expiration: 1983-01-11

Description

1966 E. D. FISHER 3,229,290

RELEASABLE BALLOON DECOYS Filed March 6, 1953 4 Sheets-Sheet 1 INVENTOR EVAN D. FISHER TTORNEYS Jan. H, 1966 E. D. FISHER RELEASABLE BALLOON DECOYS 4 Sheets-Sheet 2 Filed March 6, 1953 INVENTOR EVAN D. FISHER ATTORNEYS Jan. 11, 1966 Filed March 6, 1953 E. D. FISHER RELEASABLE BALLOON DECOYS 4 Sheets-Sheet 5 INVENTOR EVAN D. FISHER ATTORNEYS Jan. 11, 1966 E. D. FISHER RELEASABLE BALLOON DECOYS 4 Sheets-Sheet 4 Filed March 6, 1955 United States Patent 3,229,290 RELEASABLE BALLDON DECOYS Evan D. Fisher, 9014 Spring Hill Lane, Chevy Chase, Md. Filed Mar. 6, H53, Ser. No. 340,935 6 Claims. (Cl. 343l8) (Granted under Title 35, US. Code (1952), sec. 265) The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a decoy balloon launching system, and more particularly to an automatic balloon inflating and releasing system adapted for launching radar decoys from surface vessels.

In the rapid advancement of modern warfare it is frequently advantageous to position radar decoys at predetermined locations at sea, and it has been practicable to employ balloons carrying a reflective material for this purpose, usually launched from a surface vessel. In general, the prior systems for placing such decoy balloons in operation from aboard a vessel at sea has been to manually inflate the balloons from gas flasks and to drop them over the side to the surface of the water. In case of high winds, or other adverse weather conditions, balloon launching operations had to be discontinued until sufliciently calm conditions prevailed to prevent danger to members of the launching crew of being swept overboard. Also, such adverse weather conditions usually prevent present inflating and releasing balloons without rupturing them as they are subjected to weather on the vessels deck. The balloons presently utilized are approximately six feet in diameter and when subjected to high wind pressures, the neck of the balloon when attached to the nozzle of the gas flask or otherwise anchored is placed under high stresses that quickly ruptures the balloon neck. Furthermore, large banks of helium flasks are required on board the vessel thereby occupying space usable for critically needed gear.

The present invention enables personnel aboard a surface vessel to launch radar decoys quickly and efiiciently without danger to the personnel or rupture of the balloons in any Weather encountered. The balloon inflating system provides an automatic method for launching radar decoys at any predetermined location at sea which will give simulated signals to radar of submarines, surface ships, and aircraft. The entire system including the radar decoys is packed in a container which occupies very little space and consequently enables a vessel to carry a large number of these containers without jeopardizing space requirements. The decoy balloon is launched by simply dropping the contents of a container into the water, eliminating the necessity of inflating and releasing the balloon fro-m the hazardous deck of the vessel. The action of the water on a chemical contained in the unit inflates the balloon to carry the reflective material to its operational position.

The system is vented to the sea so that a water-activated chemical within the system may automatically generate gas to inflate the balloon. It is impractical to employ a rigid hermetically sealed tank to support the inflation system while the balloon is inflating, because of its size and weight, so that a non-rigid structure or a float bag as it is called herein, is provided which successfully operates on the surface of the water. The gas generated by the wateractivated chemical escapes into the float bag to maintain the system at water surface level and to inflate the balloon which is connected to the float bag by a one-way valve. The one-way valve is responsive to the water level within the float bag and serves to maintain the inflation system on the surface of the water until the water-activated chemical is expended, at which time the balloon is automatically released. A solid float structure is attached to the balloon to anchor it at a predetermined altitude by means of a connecting line to which are attached the reflective materials which act as the radar decoys. Each decoy comprising an elongated reflecting material such as a strip of thin aluminum foil.

An object of the present invention is the provision of a balloon inflating and releasing system for launching airborne radar decoys from a surface vessel.

Another object is to provide a balloon inflating and releasing system which operates automatically when dropped into the water.

A further object is to provide a balloon launching sys tem which remains on the surface of the water while the balloon is being automatically inflated.

Still another object of the invention is the provision of a balloon launching system that automatically releases the inflated balloon from the gas generator.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein:

FIG. 1 is a perspective view of a preferred embodiment of the invention in operation;

FIG. 2 is a side view, partly in section, of the embodiment of the invention shown in FIG. 1;

FIG. 3 is a vertical cross sectional view of the preferred embodiment of the gas generator shown in FIG- URE 2;

FIG. 4 is a plan view of a section of the preferred embodiment taken on the line IV-1V of FIG. 2, looking in the direction of the arrows;

FIG. 5 is a perspective view of the one-way valve; and

FIG. 6 is a side view, partly in section, of the preferred embodiment of the invention as it is packed for launching.

Referring now to the drawings, there is shown in FIG. 1 a preferred embodiment as it appears in use comprising a balloon 11 composed of a flexible resilient material, which is impervious to gas such as pure gum or the like, a resilient impervious float bag 13 connected to the balloon in a manner to be described later, a wooden float 15, and a line 17 securing the balloon to the wooden float and supporting streamers 19 of a reflective material, such as thin strips of aluminum foil or other materials having similar characteristics.

In FIG. 2, the preferred embodiment is shown immediately after being dropped into the water from a surface vessel and in the process of inflating the balloon 11. The balloon is provided with a neck 21 which is secured to a neck piece 23 by a lock ring 25 forcibly depressing a circumferential portion of the neck 21 into a neck piece groove 27, the lock ring being preferably covered with an impervious tape 29 to prevent the possibility of rupturing the balloon 11 by the ring 25. The neck piece 23- is provided with a internal flange 31 and, longitudinally spaced therefrom, with internal threads 33 which threadably engage external threads 35 of a coupling 37 which interconnects the balloon 11 and the float bag 13. Between the flange 31 on the neck piece 23 and an end face 39 on coupling 37 is supported a oneway or check valve 41, later to be described, and lateral flanges 43 and 45 of a cylindrical short housing 47 and a cylindrical long housing 49, respectively.

The short housing 47 protrudes into the balloon 11 and serves to prevent the balloon from completely collapsing and interfering with the operation of the check valve 41. The short housing is formed with a plurality of longitudinally spaced apertures 51 in diametrically opposed relationship and an end 53 reduced in diameter, as shown in FIG. 2, and fitted with a rubber grommet 55 to protect the balloon. The long housing 49 protrudes into a float bag 13,, to be later described, and is formed with a plurality of longitudinally spaced apertures 57 in diametrically opposed relationship, for a purpose to be later described. The lower end of the long housing 49 is fitted with a cap 61 having a bore 63 serving as a guide for a longitudinally movable float arm 65. The float arm consists of a thin wall tubing with

solid screw inserts

67 and 68 at each end thereof and a limit disc 69 fixedly secured thereto to limit the downward movement of the float arm 65. The lower end 68 of the float arm 65 is attached to a float 73, and the upper end 67 has threaded thereon a hexagonal valve member 70 provided with a rubber gasket 71 of a predetermined diameter secured thereto and facing the check valve 41. The hexagonal valve member 70 has a cross-corner diameter slightly less than the inside diameter of the cylindrical long housing 49 to provide suflicient clearance for the longitudinal movement of the float arm 65 within the long housing 49. The rubber gasket 71 of the valve member 70 serves to seal the check valve 41 when the float bag 13 extends from the water less than a predetermined length needed to support the decoy.

As previously mentioned, the float bag 13 is of impervious material, and serves to retain gas therein where the washer 71 is forced upward by the float 73. The float bag is elevated by the gas trapped therein until such time as the apparatus is at a suitable height above the water. The float 73 then opens the passage to the balloon 11 and allows the gas to enter. However, if the water level in the float bag 13 again rises, the passage is again closed.

The check valve 41 consists of a valve disc 75 having a plurality of apertures 77 therethrough being juxtaposed to a valve gasket 79. The gasket 79 consists of a upwardly extending hinge lid 81, which is adapted to completely cover the apertures 77 when in a closed position, and a weight 83 secured to the hinged lid to provide added weight thereto and thereby increase the inertia of the hinged lid to the flow of gas into the balloon 11. The check valve 41 is rigidly supported between the flanges 43 and 45 of short housing 47 and long housing 49, respectively, by the threaded engagement of the coupling 37 with the neckpiece 23. The float arm 65 is adapted to longitudinally reciprocate within the long housing 49 between the limits determined by the limit disc 69 in a downward direction and in an upward direction by the rubber gasket 71 of the valve member 70 abutting the thin valve disc 75 to seal the apertures 77.

The coupling 37 is formed with a circular flange 85 projecting in a horizontal direction and a groove 87 adapted to receive the line 17. The float bag 13 is cylindrically shaped and of a predetermined length with the upper end tapered to a narrow circular opening which is fixed to the circular flange 85 of the coupling 37, by any securing material, such as cement. The lower open end 89 of the float bag 13 is provided with a grommet 91, composed of several loops of piano wire, or the like.

The grommet S-1 serves as a stifliening member for the resilient float bag as as to maintain the lower portion of the float bag 13 in a continuously open or inflating position.

At a predetermined distance above the grommet 91, the float bag 13 is provided with a number of apertures 93 equally spaced about the periphery. Each aperture 93 is provided with a rubber grommet mounted therein to support a weight 95 by any securing device, such as a screw and nut, or the like. The weights 95 aid in maintaining the float bag 13 in a vertical position when on the surface of the water. At a set distance above the grommet 91 the float bag is provided about its periphery with a number of equally spaced apertures 97 each adapted to receive the threaded end 98 of a folding arm 99 of the spider 100. Each aperture 97 is provided with a rubber grommet to support the threaded end 98 by any suitable securing device, such as the concentric nuts 101, or the like. Each folding arm 99 is provided with a bore 103 near the inner end thereof, so that each folding arm may be pivotally coupled to the hub 105 of the spider by a wire loop 107 passing through the bores 103 and through the hub 105. The hub is constructed so that each folding arm is restrained from any upward movement, relative to the hub, by stops 109; however, the folding arms are free to pivot downward relative to the hub to facilitate packing of the float bag 13. The hub 105 is provided with a plurality of apertures 111 to decrease the overall weight of the hub and to facilitate the attachment of a wireholder 113 to the hub. The wireholder is looped through two adjacent apertures 111 and extends downward into a gas generator 115 to secure it to the hub 105. The length of the wireholder 113 is adjusted so that the greater part of the gas generator is covered by the float bag 13.

As shown in FIGURE 3, the gas generator 15 comprises a cylinder 117 secured to a base plate 119 as by welding, or the like. The wireholder 113 extends down along the inside surface of the cylinder 117 and across the upper face of the base plate 119, with a disc 121 be tween the portion of the wireholder lying across the base plate and a predetermined portion of a water-activated chemical 123, such as lithium hydride, or the like. The chemical 123 is compacted within the gas generator under a pressure which serves to control the generating rate of the gas, and to maintain the wireholder 113 firmly between the base plate 119 and the disc 121 until the chemical 123 is substantially expended. A canister cover 125 is secured to the base plate 119 by any suitable securing device such as the screw 127, or the like. The cumulative weight of the cylinder 117, base plate 119, disc 121, and canister cover 125 is such that the balloon inflating system will remain on the surface of the water until the chemical 123 is expended and the gas generator 115 is released from the wireholder 113, whereupon the balloon 11 elevates the system to a predetermined altitude, as hereinafter explained.

Where lithium and calcium hydride are reacted with water, they form the corresponding hydroxides which can solidify over the surface of the hydride. However, where the reaction takes place in an adequate supply of water with agitation, these deposits are dispersed into the water. In the present invention, it has been found that the evolution of gas from a submerged chemical container supplies suflicient agitation, where the chemical is exposed to water only at the top, so that the evolved gas is continuously passing through the Water causing the reaction.

The steam which may be formed by the reaction of the hydride with water is condensed in passing through the water above the chemical container. Water is therefore prevented from entering the balloon by maintaining the balloon vent a suitable height above the water as previously explained, and by passing the gas through water before it enters the float bag 13.

The line 17, securely fastened at the upper end about the groove 87 of the coupling 37, has the lower end fastened to the wooden float 15. The wooden float is constructed of a predetermined weight to maintain the elevated balloon 11 captive and not free to soar into the atmosphere so as to lose its eflectiveness as a radar decoy. The reflective material 19 consists of a plurality of thin streamers or strips 127 attached to the line 17 at a set distance between the coupling 37 and the wooden float 15.

In FIG. 6, the preferred embodiment of the invention is shown packed in a canister 129 to facilitate handling and storage aboard a vessel. The canisters can be stored in a vessel in any available space without requiring special protection to the water-activated chemical 123, the balloon 11, or the reflective material strips 127. The plurality of strips 127 are rolled, one on top of the other, about the periphery of the wooden float which is placed within the canister 129 adjacent the folded float bag 13 and the deflated folded balloon 11. The deflated balloon is covered with an ordinary paper bag 131 to protect the balloon from any injury caused by the movement of the balloon within the canister 129, especially as to excessive friction between the balloon and the inside surface of the canister or the reflector strips 127. The canister cover 125 is secured to the canister 129 by a removable metal strip 133 which overlaps the edges of the canister and the canister cover, and secured thereto by any suitable attaching means as soldering, or the like. The metal strip 133 is provided with a metal ring 135 to facilitate removal of the metal strip when it is desired to launch the decoy system. The canister is provided with a handle 137 to facilitate handling of the system.

In operation, the balloon inflating system is launched from a surface vessel in the simple operation of removing the metal strip 133, while grasping the handle 137, and allowing the contents of the canister 129 to fall into the water. As soon as the system strikes the water, the gas generator 115 sinks below the surface because of its weight, thus causing the water to come in contact with the chemical 123 and to quickly generate gas. The weights 95 will cause the float bag 13 to substantially cover the gas generator and direct the flow of gas to the float bag 13. If the water level within the float bag 13 reaches the float 73 and commences to rise further, the float arm 65 will be moved upward by the rising of the float until it seals the apertures 77 of the check valve 41 which prevents the flow of water into the balloon 11. As soon as sufficient gas has been generated within the upper portion of the float bag to lower both the water level and the float 73, the gas will flow through the apertures 57 of the long housing 49 past the valve member 70 and through the apertures 77 of the check valve to raise the hinged lid 81, and then through apertures 51 and end opening 53 of the short housing into the balloon 11. In this manner, as long as the water level within the float bag is low enough to prevent the float 73 from moving upward to close the check valve, the gas in the upper portion of the bag 13 will flow into the balloon 11 to inflate it.

The float 73 controls the amount of gas in the upper portion of the float bag 13 to maintain the balloon inflating system on the surface of the water until the balloon is sufficiently inflated and the chemical 123 is completely expended to release the gas generator from the float bag 13. The generated gas accumulates in the float bag and is allowed to flow into the balloon 11 only when the volume of gas in the float bag 13 exceeds that required to maintain the system on the surface of the water. As soon as the accumulation of gas in the float bag 13 is lowered to the point where the water level raises the float 73, the flow of gas into the balloon 11 is stopped by means of the float arm 65 until the accumulation of gas in the float bag 13 lowers the water level and the float, so that any excessive accumulation of gas may again commence to inflate the balloon 11. The process of generating gas to maintain the system buoyant on the surface of the Water and to inflate the balloon 11 with the excess gas from the float bag 13 continues until the chemical 1 23 is completely expended.

The gas generator is released from the wireholder 113 when the chemical 123 is completely activated, since the wireholder is merely held therein by the compressed chemical. As soon as the wireholder releases the gas generator, it sinks to the bottom while the inflated balloon 11 elevates to an altitude determined by the length of the line 17.

As the balloon 11 ascends, the line 17 and the reflector strips 127 are unrolled from the wooden float 15 to assume the operational altitude as shown in FIG. 1.

For the purposes of illustration of one embodiment of the present invention, strips of aluminum foil 127 are supported above the surface of the water by a SOD-gram weather balloon 11 of natural latex with a capacity of 45 cubic feet. The float bag 13 has a length of 38 inches and a diameter of 8 inches at the lower open end, and constructed from nylon 0.9 ounce per square yard medium tenacity yarn coated on both sides with neoprene. The float bag material has a total weight of 5 ounces per square yard and tensile strength of 40 pounds per inch. The weights consist of four lead fishing sinkers, each weighing one ounce. The gas generator 115 has 1% pounds of 93% pure lithium hydride compressed within the cylinder 117 by a pressure of twenty tons.

Various modifications are contemplated and may obviously be resorted to by those skilled in the art without departing from the spirit and scope of the invention, as hereinafter defined by the appended claims, as only a preferred embodiment thereof has been disclosed.

What is claimed is:

1. A balloon inflating and releasing unit for radar decoys comprising a balloon having a vent, a resilient float bag sealed to said vent, a check valve interposed between said balloon and said float bag, a wooden float, a line connecting said wooden float to said float bag, a gas generator releasably secured to said float bag and being partially enclosed therein, and valve means responsive to the water level in said float bag for preventing passage of gas from said float bag and said balloon when the height of the float bag above the water is below a predetermined level.

2. The invention as defined in claim 1 but further characterized by a plurality of reflectors secured to said line for operation as radar decoys.

'3. A balloon inflating and releasing system comprising a balloon, a gas generator producing a lighter-than-air gas when submerged in water, a float bag connected to said balloon and said gas generator, a check valve coupling said balloon and said float bag, said gas generator being immersed in water and operating within said float bag to thereby inflate said balloon.

4. The invention as defined in claim 3 but further characterized by said gas generator comprising a cylindrical container having an open upper end, a water-active chemical compressed under high pressure into said container, a wireholder having a first end extending into said container and maintained therein by said water-active chemical, and said wireholder having a second end secured to said float bag whereby after the water active chemical is expended the first end of said wireholder is released and the gas generator sinks to the bottom and said balloon and said buoyancy means use out of the water.

5. A balloon inflating and releasing unit for launching radar decoys from a surface vessel comprising, a balloon, a gas genera-tor containing an expendable chemical releasing a lighter-than-air gas when exposed to water, reflecting material attached to said balloon, and means including the expendable chemical releasably attaching said balloon to said generator, said attaching means including means operative automatically responsive to substantially complete expendature of said chemical for releasing said balloon from said generator.

6. A radar decoy launching unit comprising a balloon, an impervious float bag, a one-Way check valve connecting the balloon to the float bag, a gas generator containing an expendable chemical releasing a lighter-than-air gas when exposed to water, and means including the expendable chemical for releasably attaching the generator to the float bag, said attaching means including means opera- References Cited by the Examiner UNITED STATES PATENTS 2,334,211 11/1943 Miller v102--7 X 2,470,783 5/1949 Mead 343l8 2,489,337 11/1949 Sperling 34318 BENJAMIN A. BORCHELT, Primary Examiner.

SAMUEL BOYD, ARTHUR M. HORTON, Examiners.

tive by substantially complete expenditure of the chemical 10 S. H. GOLDMAN, R. W. ERICKSON, Assistant Examiners.

Claims

5. A BALLOON INFLATING AND RELEASING UNIT FOR LAUNCHING RADAR DECOYS FROM A SURFACE VESSEL COMPRISING, A BALLOON, A GAS GENERATOR CONTAINING AN EXPENDABLE CHEMICAL RELEASING A LIGHTER-THAN-AIR GAS WHEN EXPOSED TO WATER, REFLECTING MATERIAL ATTACHED TO SAID BALLOON, AND MEANS INCLUDING THE EXPENDABLE CHEMICAL RELEASABLY ATTACHING SAID BALLOON TO SAID GENERATOR, SAID ATTACHING MEANS INCLUDING