Controllably Submersible Buoy

Abstract

A mooring buoy of sufficient size to permit mooring of ships thereto and a control system to control the rate of ascent and descent of the submersible buoy.

Parent Case Text

This is a continuation of application, Ser. No. 873,038, filed Oct. 31, l969, now abandoned.

Description

CROSS REFERENCES AND BACKGROUND

Inflatable buoys are known in the art. For example, U.S. Pat. No. 3,126,559 to D. O. Alexander shows an acoustically controlled inflatable buoy. In this patent, a collapsible bag is included within a suitable superstructure. The bag is controllably and selectively inflated by means of a gas or air cylinder which is controlled from a unit at or near the surface of the water. Other retrievable type buoys are shown in U.S. Pat. No. 3,199,070 to W. E. Baier, Jr. and U.S. Pat. No. 2,594,702 to S. W. Woodard. Each of these patents suggests a buoy arrangement which may be controllably released from an anchored position subsea. In addition, other patents show or suggest buoys which can be resubmerged by means of a winch or the like. The winch is selectively operated to reel the cable for tethering the buoy whereby the buoy is submerged.

However, as is obvious, each of these buoys is a relatively small buoy such as a marker or tell-tale buoy which is utilized to mark a particular underwater location. These buoys are not sufficiently large to permit a large vessel to moor thereto. Moreover, the buoys are tethered by relatively small lines so that anchoring of a vessel would be impossible.

With the exception of the Alexander patent, the prior art shows buoys which normally have positive buoyancy relative to the water environment, these buoys are naturally inclined to float to the surface and must be restrained. In addition, the descent of the buoys is either uncontrolled or controlled only as a function of the winch operation which retracts or submerges the buoy.

Obviously, in an uncontrolled ascent and descent operation, pressure equalization within the buoy is virtually impossible. Furthermore, control of the manner in which the buoy lands upon the bottom is relatively impossible. In the winch-operated submerging system, great difficulties will normally be experienced with the winch both insofar as the powering thereof is concerned and the mechanical operation thereof with marine growth and the like.

In the subject invention, a large buoy is provided. This buoy is sufficiently large, for example on the order of 18 feet in diameter, to permit large ocean-going vessels to moor thereto. The large buoy is secured by means of a heavy chain such that a reliable anchor is provided between the mooring buoy and the bottom of the body of water. In addition, when submerged, the large buoy resists the forces applied thereto by passing ships, or the like, whereby the buoy does not inadvertently and undesirably rise from the bottom, possibly foul the props of the passing ships, and/or sustain damage upon descending back to the bottom.

The buoy is raised and lowered by means of an acoustically operated control system which selectively actuates suitable air or gas cylinders within the buoy whereby water is expelled from the submerged buoy until the negative buoyancy of the water filled buoy is effectively eliminated. As the buoy rises, the pressure thereon due to the environmental water decreases. Consequently, the air in the buoy tends to expand. It is desirable that air in excess of the amount required to maintain the pressure equalized be exhausted from the buoy.

Conversely, to accomplish descent, some of the air in the ballast chamber is vented and water is admitted into the buoy. When the ballast chamber is partially flooded, the buoy is neutrally buoyant wherein the weight of the buoy and the chain depending therefrom is approximately equal to the buoyancy of the buoy. Water is then permitted to enter the inner chamber at a slow, controlled rate. The weight deposition rate of the chain will be approximately equal to the weigth flow rate of water into the buoy. Consequently, the buoy descends at a controlled rate. Thus, a suitably "soft landing" of the buoy on the bottom may be attained. This type of landing prevents damage due to impact. As well, a hard landing wherein the buoy could conceivably be imbedded in a mud bottom is avoided.

Consequently, one object of this invention is to provide a buoy which is controllable as to ascent and rate of descent.

Another object of this invention is to provide a buoy which is suitable for mooring of large vessels.

Another object of this invention is to provide a submersible buoy which has few maintenance requirements.

Another object of this invention is to provide a submersible buoy which is remotely controlled.

DESCRIPTION OF DRAWINGS

The above mentioned and other objects and advantages of the subject invention will become more readily apparent when the following description is read in conjunction with the attached drawings in which:

FIG. 1 is a substantially pictorial, partially cut-away, drawing of the buoy of this invention;

FIG. 2 is a top view of the buoy of the instant invention, partially in section;

FIG. 3 is a side veiw of the buoy of the instant invention taken along the line 3--3 of FIG. 2;

FIG. 4 is a schematic diagram of the hydraulic control system for the buoy of the instant invention;

FIG. 5 is a schematic showing of the sequential operation of the buoy during the ascent and descent thereof; and

FIG. 6 is a block diagram of the control circuitry associated with the buoy of the instant invention.

In each of the drawings, similar components bear similar reference numerals .

DESCRIPTION OF A PREFERRED EMBODIMENT

Referring now to FIG. 1, there is shown a pictorial representation of a mooring buoy such as described herein. The showing is partially cut away to show some of the interior detail. Buoy 10 is shown floating substantially at the surface 33 of a body of water. A chain 28 is connected to a suitable anchor device 29 which may be a large concrete block or any similar suitable device. Chain 28 is connected (as better shown in FIG. 3) to a central mooring strong back element 11.

Buoy 10 is a substantially right circular cylindrical unit and typically has a diameter of 18 feet. Top deck 12 is substantially flat. Guard rail 13 is affixed to deck 12 in a suitable manner. On or more cleats 18 are affixed to deck 12 in a suitable manner whereby small work boats or the like may be moored thereto. A guard channel 17 is affixed to deck 12 of the buoy. Guard channel 17 includes two opposing members which are formed, as for example by rolling or the like, whereby no sharp edges are presented in the space between the sides of channel 17. A suitable cross-member 16 is connected between the sides of channel 17. Cross-member 16 is a rod or tube which is affixed to the side members of channel 17 by any suitable method such as welding or the like. Cross-member 16 is spaced from deck 12 by a distance which is sufficient to permit passage therebetween of standard mooring hawsers. The hawser is then looped over the central mooring element 11 which, as shown, extends above the deck 12 and includes a flanged end portion. With these elements and the cooperation therebetween, the hawser is prevented from slipping off mooring element 11 and, as well, does not tend to tip buoy 10 significantly from the vertical position.

OUter shell 20 of buoy 10 is fabricated of a suitable material such as carbon steel with appropriate corrosion protection being afforded by marine primers and paint. Bottom deck 35 is attached to peripheral wall 20.

Interior wall 21 also has a substantially right circular cylindrical configuration concentric with outer wall 20. The compartment defined by wall 21 may have an outside diameter on the order of 10 feet. Inner wall 21 may be fabricated of concrete, steel, or a concrete-filled steel annulus. The latter wall material is suggested for both strength and ballast.

Thus, there are two, concentric, right-circular, cylindrical compartments defined by the inner and outer walls 21 and 20, respectively. A plurality of bulkheads 22 is connected between the inner and outer walls to provide structural strength as well as to properly space the compartmental walls. Each of the bulkheads 22 has an opening 23 therein. The openings permit communication between the sections of the outer compartment. Thus, in the flooded condition, water may flow from one section to the next via the openings 23. However, the openings 23 are designed to prevent excessive sloshing of water in the outer compartment, especially when the outer compartment is only partially filled.

A plurality of bulkheads 34 are located in the inner compartment between the inner surface of inner wall 21 and the axial strong back mooring element 11. Bulkheads 34 may be aligned with bulkheads 22 or, in the alternative, they may be arranged at different spacing. Bulkheads 34, include openings 27 therein for the same purpose as openings 23 in bulkheads 22.

A plurality of pressurized gas cylinders 24 are provided in buoy 10. In the preferred embodiment, cylinders 24 are disposed adjacent the inner surface of outer wall 20.

A pair of access ports 14 and 14A are provided in deck 12. The number of access ports is not limited to two; any desirable number may be utilized. Acess ports 14 are provided such that the interior of buoy 10 may be reached by maintenance personnel. Thus, the air bottles may be recharged or any other internal gear may be serviced as necessary.

An electronic control package 25 is mounted in the outer compartment between the inner and outer walls. The electronic control package is described in more detail hereinafter. However, it is noted at this point that the electronic control package is utilized to control the operation of the pressurized gas bottles, vents associated therewith, and valves for selectively admitting water and thereby flooding the respective compartments of buoy 10.

Suitable marine fenders 15 are disposed around the periphery of buoy 10. A suitable ladder 19 is provided to permit access to deck 12 of buoy 10. A hydrophone 50 is mounted at the periphery of buoy 10 at a location which will remain below the water surface even when buoy 10 is surfaced. Hydrophone 50 receives signals from the surface control unit and communicates same to electronic control package 25.

Below the right circular cylindrical portion of buoy 10 is a substantially frusto-conical section 31. A landing surface which, as will be seen hereinafter, is in the form of a ring 32, is formed at the tapered end of conical section 31. A plurality of ports 30 are provided in the outer surface of the frusto-conical section 31. As will appear hereinafter, ports 30 may comprise vents or ports for the venting of air and water or intake of water into the system.

Referring now to FIG. 2, there is shown a top view of the buoy partially broken away to show some interior detail. Some of the external detail has been omitted for purposes of clarity. As noted, a centrally located strong back element 11 such as a rod or pipe-like unit is axially located relative to buoy 10. The access ports 14 and 14A are shown. The covers for these access ports may be bolted or otherwise fastened to the buoy. As shown in FIG. 2, the outer surface 20 may be fabricated of a relatively thin material such as a sheet of carbon steel. The inner wall includes annulus 21 shown filled with concrete 26. Thus, an inner and an outer compartment are provided. A plurality of bulkheads comprising outer bulkheads 22 and interior bulkheads 34 are positioned as described supra. The bulkheads extend radially from the center of buoy 10 toward the cylindrical wall unit which forms the periphery of each of the compartments.

Also shown in FIG. 2 is valve 106 and suitable conduit 108. Valve 106 is shown on the interior of the inner compartment. In fact, valve 106 may be, alternatively, connected "in-line" with the conduit 108. Conduit 108 extends between outer wall 20 and inner wall 21 and passes completely through each of these walls. Thus, depending upon the status of valve 106, water can selectively pass into the inner chamber from the exterior of the buoy thereby flooding the inner chamber if the external opening of the conduit 108 is submerged.

Referring now to FIG. 3, there is shown a side view of the buoy taken along the line 3--3 in FIG. 2. The outer wall 20 and inner wall 21, with concrete lining 26, are more clearly shown. In addition, it is obvious that decks 12 and 35 include concrete reinforced portions 40 and 99, respectively. Clearly, the reinforced portions 40 and 99 represent the bottom and top members of the right-circular, cylindrical device which encloses inner compartment I. The electronic package 25 is shown in dashed outline in a typical mounting.

The concical support section at the base of buoy 10 includes conical surfaces 31 and 31A. These surfaces are stiffened by structural members 42 and 43, respectively. Structural members 42 and 43 are representative of a plurality of similar stiffeners which are spaced and arranged to form a conical member when the outer sheath (such as surface 31 or 31A) is applied. Bulkheads 35 are attached to the structural members 42 and 43 as well as to the vertical support member 41. Holes 36 are provided both to permit passage of water from one section of the support cone to another, and to reduce the weight of structure included within the conical section.

Annular ring 32 is connected to the bottom end of upright supports 41. At the opposite ends, the support members 41, 42 and 43 are connected to a suitable support structure 46 which substantially spans the entire buoy 10. Structural member 46 is affixed to the bottom portion of buoy 10 by suitable means.

Vent 101 and valve 100 are disposed adjacent to deck 12 and support member 40. Vent 101 permits air to escape from compartment I when vavle 100 is open. Vent 105 located in deck 35 and support member 99 permits water to be expelled from compartment I when check valve 104 is open. Conduits 108 and 109 (which may be pipes or the like) pass through walls 26 and 20. Valves 106 and 107 are associated with conduits 108 and 109. Thus, depending upon the status of valves 106 and 107, water may selectively flow in compartment I. The different lines permit different rates of flow therethrough when the associated valve is open.

A suitable fitting 45 is attached to the central strong back column 11. The column and fitting may be joined by welding or the like. A suitable coupling 44, which is well known in the art, may be connected to fitting 45 by means of a pin or the like. Chain 28 is connected to coupling unit 44 by an additional pin or the like.

Referring now to FIG. 4, there is shown a schematic representation of the hydraulic control system for the buoy. The heavy outlines represent decks 12 and 35, inner wall 26, and outer wall 20, respectively. Since this is a schematic showing, a scale relationship is, of course, not utilized. A plurality of cylinders 24, 24A, 24B and 24C represent the gas bottles which are dispersed around the periphery of buoy 10. Normally, as shown in FIGS. 1 through 3, bottles 24-24C are disposed adjacent the inner surface of outer wall 20. In a typical embodiment, cylinders 24-24C represent four separate groups of 24 bottles of compressed gas per group. The number of bottles per group is not limitative but suggests the necessary complement which permits the buoy to be raised when the bottles are rendered operative. Of course, the number of bottles is merely typical. Depending upon the buoyancy requirements, the size of the bottle and the like, other numbers of bottles of pressurized gas may be utilized.

A separate bottle 200 is representative of an optional emergency arrangement wherein a further plurality of pressurized gas bottles is utilized. The emergency bottles are utilized only in the event that the standard bottles 24-24C are incapable of supplying sufficient gas to cause the buoy to rise either due to a defect in the bottles, leakage in the buoy or the like. Each of the bottles is shown to include a valve 213 connected thereto to regulate gas flow therethrough. A similar valve 214 is connected to a charging connector with an integral check valve 215 associated with each of the banks of bottles. Charging connector 215 is, when necessary, connected to a suitable external source for recharging the gas bottles with gas after usage. Valve 214 controls gas flow therethrough. A shut-off valve 210 is connected to each of the gas bottles. In one position, for example the position shown, each valve 210 is shut to prevent gas flow from the associated pressurized bottles. When energized, as described hereinafter, each valve 210 is opened so that compressed gas flows therethrough in the direction of the solid line arrow. Spring 216 or the like is associated with each of valves 210 in order to provide fail-safe operation to the closed position. That is, when the control signal is removed from the valve, spring 216 causes valve 210 to assume the position shown in the drawings.

As is seen, each of valves 210 is connected to common line 220. Common line 220 is connected via check valves 221 to vents 211 and 212. Vents 211 and 212 open into compartments II and I, respectively. Thus, when valves 210 are placed in the open position, the gas from pressurized bottles 24-24C is supplied to common line 200 and, thus, to compartments I and II.

When the pressurized gas is applied to the respective compartments, the water contained in the compartments becomes, effectively, pressurized and passes through check valves 104 and vents 105 thereby to be vented to the sea. As suggested in the description of FIG. 3, the pressurized water which is expelled through vent 105 effects a type of jetting action whereby the buoy is raised from the subsea surface. As noted supra, suitable conduits, or the like, may be connected from vents 105 to the ports 30 in the conical surface 31. These jets will assist the buoy to be loosened from the bottom mud.

As is seen, the solenoid portion (or pneumatically controlled portion) of each of valves 210 along with the valves 100, 102, 106, 107 and 110 is controlled by valve control device 250. As suggested, valve control device 250 includes electronic control system 25 which supplies an appropriate signal to the solenoid portion of the valve. Moreover, as may be required in some embodiments, valve control device 250 can supply electrical signals to valves 210 and pneumatic signals to the other valves or some suitable combination of electronic and pneumatic signals. The pneumatic signals may be required in the event that valves such as valves 100 and the like are large valves. The signals supplied to the valves are controlled by the electronic control system 25. Electronic control system 25 receives signals from hydrophone 50 which is mounted at the exterior of the buoy. Thus, electronic control system 25 will supply signals to the valves in the proper sequence, as described hereinafter, so that the valves are properly positioned and the compartments purged or flooded as the case may be. A further control signal is supplied to electronic control system 25 via pressure switch 300. Pressure switch 300 is connected to a suitable transducer 301 which detects, via pressure sensing techniques, the surfacing of the buoy. In particular, the signal from pressure switch 300 causes electronic control system 25 to supply a signal which closes valves 210 so that the solenoids do not discharge the batter after the buoy has surfaced.

Referring now to FIG. 5, there is shown, schematically, the operation of buoy 10. Typically, buoy 10 is located at or adjacent the bottom of the body of water with compartments I and II flooded, or substantially flooded, as shown in diagram A of FIG. 5. Because of the inherent weight in the flooded condition, the buoy rests firmly on the bottom of the body of water where it is free from interference with or by passing ships. Upon the arrival of a vessel 500 which is desirous of mooring in the area, a suitable acoustical signal is generated either by means of a transducer 502 disposed at or adjacent the vessel or by a suitable signaling device located in the vicinity of the mooring buoy. The signal is received by hydrophone 50 (see FIGS. 1 through 4) which causes electronic control system 25 to produce suitable control signals. The control signals cause valve 210 to open wherein the pressurized gas in one set of bottles 24-24C (see FIG. 4) is discharged into compartments I and II. As discussed previously, the discharge of the pressurized gas causes the water in compartments I and II to be purged from the compartments via check valves 104 and vents 105. As the water is purged from compartments I and II, a condition of positive buoyancy is effected in buoy 10. Buoy 10 will then begin to rise toward the surface of the water.

It may be desirable, to have a gas discharge rate which is relatively large in order that mud around the buoy 10 may be "jetted" away. This operation overcomes any natural resistance which may be incurred due to a vacuum or suction created by a soft mud bottom.

After the buoy has started to rise (as shown in segment B), the positive buoyancy causes the buoy to continue to rise. Inasmuch as the external pressure will decrease, and the internal pressure will increase due to the continued operation of the air bottles, the volume of the gas in the purged compartments will tend to expand thereby hastening the purging process. In order to compensate for the increasing internal pressure (relative to the environment), check valves 104 will also permit the discharge of the pressurized gas therethrough as suggested in section C. However, the check valves will be properly defined so that positive buoyancy of the buoy is maintained after the buoy has surfaced.

When the buoy nears the water surface, pressure switch 300 (see FIG. 4) closes all of the valves wherein pressurized gas from bottles 24-24C is no longer supplied to the internal compartments of the buoy. Thus, an equilibrium condition is achieved across check valves 104 whereby the valves close and the buoy will float at a predetermined level as shown in Section D. For example, the top deck of the buoy will be several feet above the water surface. At this point, by means of a suitable crew boat, or the like, hawser 501 is affixed to the mooring buoy as described previously and as shown in Section D. It is understood that with tide changes and the like, the lines may tend to assume different geometrical configurations but, nevertheless, vessel 500 is securely anchored via hawser 501, buoy 10, and anchor chain 28 depending from the buoy.

When the necessity or desirability of mooring vessel 500 terminates, hawser 501 is removed from buoy 10 and a suitable signal is generated by transducer 502 or from a suitable control station. This signal is received by hydrophone 50 and is supplied to electronic control system 25. This signal operates to provide signals via valve control device 250 to open valves 102, 106 and 110. As will be seen, opening of valve 110 permits in-flow of water into compartment II to flood this compartment. The concurrent operation of valve 102 permits the venting of compartment II whereby any entrapped air may be expelled. Valve 106 serves a similar function in allowing water to enter compartment I. However, the inlet port 108 is located high on the buoy and is connected through a restriction 108A such that the rate at which water enters compartment I is controlled. Thus, as shown in sections E and F of FIG. 5, compartment II will tend to flood substantially rapidly thereby causing the mooring buoy to have substantially neutral buoyancy and to float at or near the surface of the water. However, inasmuch as water is entering compartment I through valve 106 at a controlled rate, a controlled rate of descent of the buoy is effected as shown in sections F and G of FIG. 5.

The rate of flooding via valve 106 is controlled by the restriction or nozzle 108A. The rate is pre-determined and is a function of the size, weight and desired deposition rate of the anchor chain. That is, as the chain is deposited on the bottom, it is no longer supported by the buoy. Since the chain is no longer being supported by the buoy, an increased amount of water is required to cause the buoy to continue to sink at the pre-determined rate. In a preferred embodiment, the rate of water input is preset to cause the buoy to descend or sink at the rate of approximately 0.5 feet per second. This rate of sinking is believed to avoid any damage to the buoy when striking a hard bottom as well as to avoid burying the buoy in a soft, muddy bottom.

When, as shown in section H of FIG. 5, the buoy has reached the bottom, valves 100 and 107 are opened. Valve 100 provides a vent to permit the escape of the air which has been entrapped in compartment I. Concurrently, valve 107 is connected via port 109 to permit fast flooding of compartment I. The fast flood and vent permit substantially uncontrolled flooding which, while undesirable during the descent of the buoy, is advantageous when the buoy has reached the bottom.

The control of valves 100 and 107 can be effected by an acoustic signal which is detected by hydrophone 50. This signal may be sequentially programmed automatically from the surface at a time which is subsequent to the descent period. For example, the descent may be known to take approximately 3 minutes. The flood signal would be generated after a period of about 5 minutes.

In the alternative, a sensing switch or the like, (not shown) could be disposed adjacent the bottom of the buoy. This switch could be operated when the buoy strikes the bottom of the body of water thereby supplying a signal via electronic control system 25 to valve control device 250 to cause valves 100 and 107 to open and thereby fast flood compartment I. After the flooding has been completed, an acoustic signal is transmitted to cause all valves to close thereby conserving electrical power.

Flooding of compartment I is desirable (and may be required) in order to securely maintain the buoy at the bottom. However, as noted supra, the fast flood is not desirable prior to the full descent of the buoy in order to prevent damage thereto.

Referring now to FIG. 6, there is shown a block diagram of the control circuit which is utilized with the subject invention. A 12 volt battery is connected to the acoustic receiver and decoder to supply power thereto. When the acoustic receiver and decoder receive signals via a hydrophone or the like, the signal is decoded and a control signal is supplied to a plurality of functions via cable 600. Cable 600 includes sufficient lines to supply the several functions. The battery and acoustic receiver and decoder are mounted in the buoy, for example in compartment II. To raise the buoy, the control signal is supplied to the pilot valve control circuit for bank 1, 2, 3 or 4 of pressurized gas bottles. The pilot valve control circuits are arranged to operate the associated pilot valves. The pilot valves are equivalent to valves 210 as shown in FIG. 4. Banks 1, 2, 3 and 4 are equivalent to bottles 24-24C as shown in FIG. 3. The emergency stepper control circuit is connected to five emergency pilot valves which are connected to emergency bottles 200 as noted supra. Bottle 200 represents five four-bottle emergency groups in a preferred embodiment. Pressure switch 300 (FIG. 4), upon detecting a pre-determined pressure condition, provides a signal which turns off the control circuits for each of the pilot valves and the stepper control circuit.

As shown in FIG. 6, each of the above enumerated functions is associated with the "rise" commands which cause the buoy to ascend. The sink control circuit also receives a signal from the acoustic receiver and decoder via cable 600. The sink control circuit supplies signals to the flood valves of compartments I and II as well as the vent valves of compartment II. It should be noted, that the flood valve associated with compartment I, as controlled by the sink control circuit, is equivalent to valve 106 which is the "slow flood" valve. The fast flood valve for compartment I, as well as the vent valve for compartment I, (equivalent to valves 100 and 107 in FIG. 4) are connected to and operated by the compartment I vent control circuit which, as shown, can be operated either by an acoustic signal which is received by the acoustic receiver and decoder or by means of a bottom sensor switch. A control circuit to shut all valves is also connected to receive a signal from the acoustic receiver and decoder device and provide a signal which turns off power to all valves. Thus, the buoy is in condition for the next operation.

A 28 volt batter may be utilized to provide the necessary electrical power for the valves. This battery, along with the 12 volt battery associated with the acoustic receiver and decoder, is mounted in the buoy. In an alternate configuration, one battery may be used with voltage regulating devices to provide other voltages that may be necessary for the electronic system.

While not shown or described, it is understood that suitable electrical connections may be provided whereby the batteries may be recharged, the pressurized bottles recharged, and other maintenance be permitted from the exterior of the buoy. In addition, a connection may be supplied to the buoy such that pressurized gas may be inserted therein from an external source in the event that the buoy develops a leak after it has surfaced. Moreover, this external source would tend to conserve the bottled gas for futher usage.

Claims

Having thus described a preferred embodiment of the invention, what is claimed is:

1. A buoy, comprising a hollow body adapted to receive water to cause it to descend to a desired level therein, check valve means for venting such water from the body, a source of compressed gas within the body, means for releasing gas from said source into said body to force water from said body through said check valve means and thereby cause said body to rise to the surface, and means adapted to be located on said body above the normal water line of said buoy when surfaced for automatically closing said gas releasing means when said body reaches said surface.

2. A buoy of the character defined in claim 1, wherein said gas releasing means includes a normally closed valve controlling the outlet from said gas source, a source of electrical power, and means powered by said power source to open the valve, and the means for closing the gas releasing means includes means for disconnecting the power source from the valve opening means to permit said valve to close.

3. A buoy, comprising a hollow body having inner and outer concentric compartments, means for admitting water to each compartment while venting gas therefrom to cause the body to descend, a source of compressed gas, means for admitting gas from said source to each chamber while venting water therefrom to cause the body to ascend, and a chain extending axially downwardly from the bottom of the body.

4. A buoy of the character defined in claim 3, wherein the means for venting water is in the bottom of the body to cause a downward jetting action.

5. A buoy comprising a hollow body having at least two separate water compartments therein each adapted to receive water to cause the buoy to descend, the compartments of said buoy being arranged to permit the buoy to normally float with a positive buoyancy when said compartments are empty of water, first inlet means for flooding one of said compartments with water at a relatively fast rate to cause said buoy to have a substantially neutral buoyancy, second inlet means for flooding another of said compartments at a relatively slower, controlled rate to cause the buoy to have controlled negative buoyancy and to descend at a controlled rate, and outlet means for venting water from each of said compartments.

6. The buoy of claim 5 wherein said first and second inlet means are valves having inlet ports, and wherein the inlet port of said second inlet means provides a greater restriction to the flow of water than the inlet port of said first inlet means.

7. The buoy of claim 5 including an outer water compartment and an inner water compartment concentric with said outer water compartment, and wherein said first inlet means is connected to said outer water compartment and the second inlet means is connected to said inner water compartment.

8. The buoy of claim 5 further including anchor means extending downwardly from the buoy.

9. A submersible buoy having a controllable rate of ascent and descent comprising a body member having first and second buoyancy chambers therein, first water flow valve means to control the flow of water from outside said body member to said first chamber, said valve means including a flow conduit with a restriction therein so that water enters said first chamber at a relatively slow, predetermined controlled rate when said valve means is in an open position, second water flow valve means to control the flow of water from outside said body member to said second chamber, said valve means having an unrestricted flow conduit so that water enters said second chamber at a relatively fast rate when said valve means is in an open position, first and second gas vent means to permit the escape of gas from said first and second chambers, respectively, each of said vent means having valve means to control said escape of gas from the first and second chambers, first and second water vent means to permit the flow of water from said first and second chambers, respectively, to outside said body member, each of said water vent means having check valve means to control said flow of water from the first and second chambers, a source of pressurized gas positioned within said body member, gas flow valve means to control the flow of gas from said source to said first and second chambers, valve control means adapted to control in predetermined sequence the opening and closing of said first and second water flow valve means, said first and second gas vent means and said gas flow valve means, so as to control the admission of water to said first and second chambers and the purging thereof during descent and ascent of said buoy, said valve control means including signal receiving means adapted for detecting signals from a remote source, and anchor means connected to said body member, said anchor means comprising an anchor chain having an anchor device connected thereto for positioning at the bottom of the body of water in which said buoy is to be located, whereby the buoy may be located at the bottom of said body of water with said first and second chambers flooded with water and may be caused to rise to the surface by a signal to said signal receiving means resulting in the opening of said gas flow valve means causing the flow of pressurized gas to said chambers, purging said water therefrom and creating a positive buoyancy so that said buoy rises to the surface, a further signal to said signal receiving means causing said valve control means to open said first and second water flow valve means and said gas vent means, the flow of water to said second chamber creating a neutral buoyancy of said buoy, the relatively slower rate of water flow to said first chamber causing the buoy to sink at a relatively slow, controlled rate, thereby avoiding damage to the buoy upon reaching the bottom of said body of water.

10. The buoy of claim 9 and including signal means for transmitting signals for selectively activating said valve control means, said signal means being located at a source remote from said valve control means.

11. The buoy of claim 10 in which said signal means is adapted to transmit acoustical signals and said signal receiving means is adapted to receive said acoustical signals.

12. The buoy of claim 9 and including third water flow valve means to control the flow of water from outside said body member to said first chamber, said valve means having an unrestricted flow conduit so that water enters said first chamber through said third valve means at a relatively rapid rate when said third valve means is in an open position, said valve control means being adapted to open said third water flow valve means when the body member has reached the bottom of said body of water and to close said third valve means together with said first and second valve means for subsequent ascent of said body member to the surface, said valve control means also being adapted to open said first gas vent means when said third valve means is opened, so that fast flooding of said first chamber is achieved after the body member has reached the bottom for more secure positioning at the bottom of said body of water.

13. The buoy of claim 12 and including pressure detection means positioned on said body member, said means being adapted to supply a control signal to said valve control means when said body member reaches the surface of said body of water, said valve control means being adapted to close said gas flow valve means upon receiving said signal from the pressure detection means.

14. The buoy of claim 13 and including a mooring element extending upward from said body member, said mooring element being adapted for the securing of a mooring hawser of a vessel desiring to moor to said buoy, said mooring element also extending downward beneath said body member and being adapted for connection to said anchor chain.

15. The buoy of claim 14 in which said first and second chambers are concentric, right-circular, cylindrical compartments and said mooring element comprises an elongated strong back element axially located with respect to said body member and said first and second chambers thereof.

16. The buoy of claim 15 and including below said body member a substantially frusto-conical section having a plurality of ports on the outer surface thereof and a landing ring positioned at the tapered end of said conical section.

17. The buoy of claim 16 in which said ports comprise vents for the venting of air and water from said body member and ports for the intake of water to said body member.

18. The buoy of claim 12 in which said valve control means comprises an electronic control system and said first and second gas vent valve means, said gas flow valve means and said first, second and third water flow valve means comprise solenoid valves.

19. A buoy, comprising a hollow body, means for admitting water to the body to cause it to descend therein at a controlled rate, means automatically responsive to the descent of said body to the surface beneath said water for admitting water to the body at a faster rate, and means venting gas from the body as water is admitted thereto.

20. A buoy of the character defined in claim 19, wherein the means for admitting water includes means on the body for engaging with said surface beneath the water and admitting said water in response to said engagement.

21. A buoy of the character defined in claim 19, wherein the means for admitting water includes means for timing the controlled descent of said body and admitting said water when said time has expired.

22. A buoy of the character defined in claim 19, including means for closing said water admitting and gas venting means, a source of compressed gas within the body, means for releasing gas from said source into said body, means for venting water from the body as gas is released thereto so as to cause the body to rise to the water surface, and means for closing the gas releasing means when said body has ascended to the water surface.

23. A buoy of the character defined in claim 22 wherein said means for closing the gas releasing means includes means automatically responsive to ascent of said body to the water surface.

24. A buoy of the character defined in claim 19 wherein the body has a compartment into which water is admitted at said controlled and faster rates, and the gas venting means includes means for venting gas from said compartment upon descent of said body to said surface beneath the water.

25. A buoy of the character defined in claim 19 wherein the body has a first compartment into which water is admitted at said controlled rate and a second compartment into which water is admitted at said faster rate, and the gas venting means includes means for venting gas from the first compartment as water is admitted thereto at said controlled rate, and means for venting gas from the second compartment as water is admitted thereto at said faster rate.

26. A buoy of the character defined in claim 25 wherein said water admitting means includes means for also admitting water to said second compartment at a controlled rate.

27. A buoy of the character defined in claim 25 including means for closing said water admitting and gas venting means, a source of compressed gas within the body, means for releasing gas from said source into each compartment, means for venting water from each compartment as gas is released thereto so as to cause the body to rise to the water surface, and means for closing the gas releasing means into each compartment when said body has ascended to the water surface.

28. A buoy of the character defined in claim 27, wherein said closing means includes means automatically responsive to ascent of said body to the water surface.