US3280782A - Marine anchor - Google Patents

Description

Oct. 25, 1966 c. H. HOLM 3,280,782

MARINE ANCHOR Filed May 24, 1965 l IVI r 1 "V CARL H. HoLM ATTORNEY United States Patent O 3,280,782 MARINE ANCHOR Carl H. Holm, Miami Beach, Fla., assignor to North American Aviation, Inc. Filed May 24, 1965, Ser. No. 457,956 4 Claims. (Cl. 114-206) This invention relates generally to marine anchors, and particularly concerns an anchor assembly having provisions for forcible anchor iluke embedment. From an applications standpoint, the invention is considered especially useful in instances where taut line mooring is required.

The instant marine anchor invention is essentially comprised of a cylinder and a piston-driven anchor shaft having attached outwardly rotatable anchor llukes. The piston-driven anchor shaft is powered for embedment purposes essentially by environmental water. The interior of the cylinder normally contains air at ambient atmospheric pressure and at the time of anchor actuation iluid openings in the cylinder upper exterior are uncovered permitting environmental water to ilow into the cylinder upper interior and act upon the piston; forces developed from the pressure difference between environmental hydrostatic pressure and the atmospheric pressure of the contained air compress the air contained in the cylinder lower interior below the piston and rapidly deploy portions of the anchor shaft and the extending anchor lukes downwardly into the anchoring medium. Such embedment is accomplished by the invention without requiring the use of an explosive propellant charge.

A primary object of this invention is to provide a marine anchor assembly with means to advantageously utilize environmental water and the hydrostatic pressure condition associated therewith for accomplishing anchor shaft and anchor lluke embedment.

Another object of this invention is to provide a marine anchor assembly utilizing environmental water and the hydrostatic pressure condition associated therewith to accomplish anchor shaft and anchor iluke embedment with a construction and means to develop comparatively high anchor shaft embedment accelerations from such hydrostatic pressure condition.

A still further object of this invention is to provide a marine anchor assembly with a construction that does not incorporate or require the use of an explosive propellant charge to develop the forces necessary for accomplishing adequate anchor lluke embedment.

Other objects and advantages of this invention will become apparent during consideration of the following specification and drawings.

In the drawings:

FIG. l is a combined elevational and sectional view of a preferred embodiment of the marine anchor assembly of this invention;

FIGS. 2. and 3 are partial sectional and plan views showing additional details of the marine anchor assembly of FIG. l; and

FIGS. 4 through 6 are elevational views showing the marine anchor assembly of FIGS. 1 and 2 at various stages in a typical deployment.

A preferred embodiment of the marine anchor invention of this application is designated in the drawings. In the FIG. l View it is illustrated as being suspended from the lower extreme of anchoring cable 11 by means of attachment bail 12. The object to be anchored is normally secured to assembly 10 at the other extreme of anchor line 11. For taut line mooring applications wherein it is desired that a damping weight be utilized, a cable 13 may be provided to connect the principal mass of assembly 10 to the embedded portions in spaced-apart relation and after separation for that purpose.

Patented Oct. 25, 1966 ice Anchor assembly 10 is essentially comprised of hollow cylinder 14, interiorly-contained piston element 15, anchor shaft 16, and an operator 17-initiator 18 combination for operatively initiating actuation of assembly 10. Cylinder 14 is provided with end flanges 19 and 20 that carry lower and upper end caps 21 and 22, respectively, through conventional fasteners 23. Piston 15 is slidably contained within cylinder 14 and is of suillcient length to interiorly cover the lluid inlet ports 24 provided in the upper exterior region of cylinder 14. Recess 25 is provided in the upper end surface of piston 15 to receive the sealing plug 26 when assembly 10 is actuated to accomplish anchor shaft embedment; the recess 27 provided in the lower end surface of piston 15 receives the upper end of shaft 16 in driving relation. The lower end of shaft 16 projects through a cooperating opening in end cap 21 and carries the retracted outwardly rotatable llukes designated 28. A point configuration is preferably provided at the lower extreme of shaft 16.

Assembly 10 is also preferably provided with a drag cone 29 in attached relation to the exterior of cylinder 14. Cone 29 functions to develop added resistance to reaction movement of cylinder 14 and aids in accomplishing embedment of anchor shaft 16 and attached tlukes 28. In some applications (extreme anchoring depths) and assembly configurations (high inherent drag) use of a drag cone such as 29 may not be necessary.

Operator member 17 is essentially in the form of a rod and is provided with a foot portion 30; further, operator 17 is slidably supported within the cooperating brackets that project laterally from end cap 21 and end flange 20. The upper end of operator 17 cooperates with the rotatable lever portion 31 of initiator 18.

As shown in FIG. 2 of the drawings, initiator 18 is secured to end cap 22 by conventional fastener devices 32. The initiator includes a retainer slide 33 preferably having a keyhole slot 34; the narrow portion of slot 34 is normally engaged with the illustrated peripheral recess provided in the upper portion of sealing plug 26 and retains sealing plug 26 in its illustrated FIG. 2 position until anchor 10 is actuated by sulllcient upward movement of operator rod 17.

Also, as shown in the drawings, a tensioned spring 35 is provided in initiator 18 to preload slide 33 and also the over-center detent mechanism designated 36. A shear pin 37 may be provided t-o supplment detent -device 36 and thereby minimizes accidental operation of lever 31 if desired; also, a pin 38 may be utilized to facilitate the assembly of anchor 10 during manufacture by retaining slide 33 in its restraining position but it must be removed prior to anchor deployment. Projecting ears may be included on slide 33 (FIG. 3) for cooperation with stops provided in the illustrated side flanges of lever arm 31 (FIG. l). This arrangement serves to retain slide 3-3 and sealing plug 26 in their FIG. 2 restrained position so long as lever 311 is not moved upwardly. When lever arm 31 is rotated by rod 17 about pin 39, the stops of the sides of lever 31 are disengaged from the side-projecting ears of slide 33 and spring '35 then moves the large portion of keyhole slot 34 into surrounding relation to sealing plug 26. Plug 26 then is freed to move downwardly within the cooperating continuous cylindrical passageway 40` in end cap 22 and initiator 18. Hydrostatic forces acting upon the upper end of sealing plug 26 will, when -anchor assembly 10 is actuated and providing the associated hydrostatic pressure is greater than the pressure of the interiorly contained air, force plug 26 into recess 25 to accomplish initial flooding of the upper interior portion of hollow cylinder 14.

Several other construction features of anchor assembly 10 are of interest. Conventional O-ring seals 41 are provided -at obvious locations throughout assembly 10 to seal the interior of cylinder 14 from exterior environmental pressure conditions. At the time of assembly the normal exterior environmental pressure, and thus the condition within cylinder 14, is ambient atmospheric pressure. Lug 42 is attached to shaft 16 to assist in securing portion 13 of anchor line 11 to the lower extreme of the assembly. A shear pin (not shown) may be provided in assembly to retain shaft 16 in its FIG. 1 position during normal handling; such shear pin, however, should not interfere with the actua-tion of assembly 10. The .top of piston is preferably spaced apart from the under-surface of end cap 22 (FIG. 2). At the time of anchor manufacture a collar 43 is connected to sh-aft 16 to assure the necessary degree of spacing.

As suggested above, anchor -assembly 10 is fabricated using conventional manufacturing techniques and when assembled includes air at .ambient atmospheric pressures within cylinder 14. As assembly 10 is lowered to considerable depths, the environmental medium (water) establishes substantial pressure differentials between the cylinder exterior and interior. The pressure differential which exists at the anchoring depth is employed to obtain the advantages of this invention.

A prototype anchor assembly 10 having 4a hollow cylinder 14 approximately 6 feet long was provided with a cooperating piston 15 of approximately 5 inches diameter. The piston length was approximately 10 inches to cover an arrangement of two circumferential rows of live uid inlets each in the cylinder upper exterior region; each inlet opening had a diameter of approximately 1% inches. The drag cone 29 attached to cylinder 14 had an -overall diameter of approximately 3 feet. A hollow anchor shaft `16 that was 1% inches in diameter extended from piston 15 and through the lower end of the cylinder by a distance of approximately inches; the projecting anchor shaft was provided with two generally opposed rotatable anchor fiukes 28 each having an overall length of approximately 7 inches extended. The prototype unit was assembled under normal conditions so that the unoccupied interior of cylinder 14 contained air at standard atmospheric pressure.

Assembly 10 was lowered at sea approximately 1,000 feet to bottom and was actuated in the manner shown by FIGS. 4 through 6. On contact with anchoring medium 45, reaction forces introduced into rod 17 at foot portion 30 cause upward movement of initiator lever 31 relative to the anchor assembly. A small degree of clockwise (FIG. 2) rotation lof lever arm 31 about axis 39 released slide 33 for movement by tensioned spring 35. Movement of slide 33 resulted in disengagement of sealing plug 26 from restraint within keyhole slot34 thus permitting the environmental hydrostatic pressures (approximately 450 psi.) to force sealing plug 26 into recess 25 and thereby open passageway 40. Seal water ported through passageway 40 into the space intermediate piston 15 and end cap 22 caused `downward displace-ment of piston 1S and initial compression of the air at atmospheric pressure within the unoccupied lower interior portion of cylinder 14. Such relative downward displacement of piston 1S further caused the complete opening of fluid inlets 24 thereby admitting fluid at environmental hydrostatic pressures into the cylinder interior intermediate end cap 22 and upper surface of downwardly displaced piston -15 at a high how rate thereby causing piston 1S to further compress the air in cylinder 14 to an equilibrium pressure. The rapid compression of contained atmospheric air is accompanied by comparatively high relatively downward acceleration of shaft 16 in opposition to reaction inertia of cylinder 14 and the components carried thereby and also in opposition to the resistance resulting from drag cone 29 if employed in the invention construction. Such rapid downward acceleration in opposition to the concurrent reaction forces causes a substantial penetration of shaft 16 and attached anchor flukes 28 into the anchoring medium 4S. See FIG. 5. On completion of anchor shaft and fluke embedment, underwater turbulence forces -acting on anchored sonobuoy 44 (the object to be anchored) and through anchoring cable 11 may be utilized to disengage cylinder 14 from shaft 16. The mass of cylinder 14 provides a damping effect for taut line mooring applications yet cable 11 remains connected to shaft 16 through cable section 13. Withdrawal forces acting upon anchoring cable section 13 cause limited withdrawal of anchor shaft 16 and simultaneous rotation of anchor flu-kes 28 to an extended position. FIG. 6 shows assembly 10 in its typical finally deployed condition.

It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred embodiments of the s-ame, but that various changes in the proportioning, size, and detail of parts may be resorted to without departing from the spirit of the invention or the scope of 4the subjoined claims.

I claim:

1. A marine ancho-r assembly for actuation by environmental fluid having `an associated hydnostatic pressure that substantially exceeds atmospheric pressure, and comprising:

(a) Hollow cylinder means having closed upper and lower ends 'and having an interior that contains gas at a pressure essentially corresponding to atmospheric pressure,

(b) Anchor shaft means partially within said cylinder means interior and slidably projecting through. said cylinder means closed lower end with attached anchor nukes positioned below said cylinder means,

(c) Piston means cooperatively positioned in said cylinder means in driving relation to said anchor shaft means and separating said cylinder means interior i-nto yupper and `lower portions each of variable volume, and

(d) Inlet port means located in the upper region of said cylinder means and arranged to conduct actuating environmental fluid from regions exterior to the 4anchor assembly into said cylinder means upper interior portion when opened,

said inlet port means being closed [from communication with said cylinder means upper interior portion by said piston means prior to actuation of the anchor assembly and being opened as a result of initial downward movement of said piston means relative tosaid cylinder means to thereby conduct suicient @actuating environmental fiuid into said cylinder means upper interior portion to continuously 4compress the gas contained in said cylinder means lower interior portion to an equilibrium pressure corresponding to the hydrostatic pressure of the environmental iiuid, to substantially accelerate lsaid piston means .and said anchor shaft means downwardly relative to said cylinder means, and to consequently embed said .anchor shaft means in an anchoring medium.

2. rIlhe invention by claim 1, wherein said piston means is provided with longitudinal spaced-apart seal means, and wherein said inlet port means is comprised of peripheral-ly positioned cylinder means openings, said piston means being positioned prior to actuation of the lanchor assembly so that said in'let port means is located intermediate said longitudinally spaced-apart seal means to further close said inlet port means fnom communication with said cylinder means interior upper and flower portions.

3. The invention defined by claim 1, wherein said cylinder means is additionally provided with separate means positioned in cooperation with said cylinder means interior upper portion for initiating actuation of the marine yanchor assembly, said separate means conducting environmental iluid to said hollow cytlinder means interior rupper portion when actuated toy initially compress the gas contained in said cylinder means lower interior portion and consequently move said pist-on means downwardly relative to said cylinder means asucient distance to change said inlet port means from `a closed condition to an open condition to additionally conduct environmental uid to said cylinder means interior upper portion.

4. The invention defined by claim 3, wherein said separate means includes a passageway means extending from the yanchor assembly exterior to said cylinder means interior upper portion, sealing plug means positioned in said passageway in longitudinal sliding relation, recess means in said cylinder means interior upper portion Ilarge enough to more than completely receive said :sealing plug means,

and restraining means preventing longitudinal sliding lo movement of said sealing plug means relative to said passageway and said recess means when engaged with said sealing plug means, said initiator means disengaiging said restraining means from said sliding plug means when actuated to permit environmental fluid to cause said sealing 3,ll8,4l7 114-206 MILTON BUCHLER, Primary Examiner.

T. M. BLIX, Assistant Examiner.

Claims (1)

1. MARINE ANCHOR ASSEMBLY FOR ACTUATION BY ENVIRONMENTAL FLUID HAVING AN ASSOCIATED HYDROSTATIC PRESSURE THAT SUBSTANTIALLY EXCEEDS ATMOSPHERIC PRESSURE, AND COMPRISING: (A) HOLLOW CYLINDER MEANS HAVING CLOSED UPPER AND LOWER ENDS AND HAVING AN INTERIOR THAT CONTAINS GAS AT A PRESSURE ESSENTIALLY CORRESPONDING TO ATMOSPHERIC PRESSURE, (B) ANCHOR SHAFT MEANS PARTIALLY WITHIN SAID CYLINDER MEANS INTERIOR AND SLIDABLY PROJECTING THROUGH SAID CYLINDER MEANS CLOSED LOWER WITH ATTACHED ANCHOR FLUKES POSITIONED BELOW SAID CYLINDER MEANS, (C) PISTON MEANS COOPERATIVELY POSITIONED IN SAID CYLINDER MEANS IN DRIVING RELATION TO SAID ANCHOR SHAFT MEANS AND SEPARATING SAID CYLINDER MEANS INTERIOR INTO UPPER AND LOWER PORTIONS EACH OF VARIABLE VOLUME, AND (D) INLET PORT MEANS LOCATED IN THE UPPER REGION OF SAID CYLINDER MEANS AND ARRANGED TO CONDUCT ACTUATING ENVIRONMENTAL FLUID FROM REGIONS EXTERIOR TO THE ANCHOR ASSEMBLY INTO SAID CYLINDER MEANS UPPER INTERIOR PORTION OPENED,

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