US2994292A - Lightweight balanced safety anchors - Google Patents

Description

1961 c. A. WINSLOW 2,994,292

LIGHTWEIGHT BALANCED SAFETY ANCHORS Filed May 25, 1959 2 Sheets-Sheet 1 F1 7 Fi 2,

IN V EN TOR.

Aug. 1, 1961 C. A. WINSLOW LIGHTWEIGHT BALANCED SAFETY ANCHOR-S Filed May 25, 1959 2 Sheets-Sheet 2 United States Patent 2,994,292 LIGHTWEIGHT BALANCED SAFETY AN CHORS Charles A. Winslow, 5640 Castle Drive, Oakland, Calif. Filed May 25, 1959, Ser. No. 815,742 9 Claims. (Cl. 114-208) This application is a continuation-in-part of application Serial No. 645,246, filed March 11, 1957, now abandoned.

This invention relates to an improved anchor of relatively lightweight construction but having holding power far in excess of conventional stock-less anchors, commonly used in the past. For example, a generally accepted standard for conventional Navy-type stockless anchors has been two pounds of holding power on sandy bottom per pound of anchor weight, for the reason that conventional anchors were limited in their ability to dig far enough below the surface of the bottom for good holding qualities. The anchor of the present invention, on the other hand, when constructed of high tensile ma terials, has hundreds of pounds of holding power per pound of anchor weight in a hard sandy bottom, where it can dig down properly and is provided with the proper scope and weight of anchor cable.

Furthermore, the present improved anchor immediately engages the bottom when a pull is applied, causing the anchor to dig in, in a straight, guided path downwardly until it is completely buried beneath the surface.

Another important feature of the invention is that the anchor, with an outer edge generally in the form of the letter M, is guided in a straight line and is prevented from rotating or spilling its load by a flat fluke arrangement and by flanges on the outside edges of the flat flukes. The entire cross-section of the anchor provides a minimum amount of resistance and a maximum amount of guiding and holding area on the flukes, all of which contribute to a maximum of holding power with a minimum of weight and resistance, thus permitting the anchor to dig into the bottom with a thin cross-section similar to the action of a double-pointed shovel, which would be continuously pressed into a sand or soft bottom on a 30 angle.

Thus, it is to be understood that the anchor has a relatively small cross-sectiona1 area in proportion to its size and can be pulled through soft mud or sand until it digs deep enough to reach a relatively hard bottom for adequate holding. The M shape of the anchor makes unnecessary such appurtenances as orossarms, stocks, crowns, and other means commonly used in the past to cause the points of the flukes to dig into the bottom. Thus a simple, compact structure is provided wherein the anchor, on being withdrawn from the bottom, can be stowed flat against the side of a hull or on deck without any extrusions such as palm-flukes, long extruding stocks, or high crowns, which occupy considerable space and provide entangling hazards for lines, chains, etc.

From research and experimental work in connection with the design and construction of anchors and comparisons with various other kinds and types of anchors, I have determined that minimum cross-sectional area and light weight are important factors in the general handling of and vthe holding power of an anchor for use on small boats, aircraft, etc., where weight is an important factor. I have, therefore, used novel construction as a feature of the invention wherein two simple, identical stampings are spot-welded back to back, forming an axis opening for pinioning the shank to the flukes. The flanges on the sides of the flukes are preferably braced with a band when the anchor is made in its stamped form, and the whole construction may be dipped in a galvanizing tank, thus making a firm, smooth, metallically bonded, rust-proof construction of maximum.

strength with minimum weight and cross-sectional area.

ICE

2 This construction, by providing minimum cross-sectional area, insures easy fluke entrance and deep penetration into a normal bottom.

Another important feature is that the construction and design provide the novel feature of forming guiding surfaces on all four dimensions of the anchor to insure that it cannot furrow, skid, or rotate and lose its hold on the bottom by being rotated or twisted clear of the bottom, as is the case with conventional stockless anchors.

In practice in the present invention, weight is not re: lied on to cause the anchor to dig. On the other hand, the guiding surfaces of the fluke faces and the guiding surfaces of the flanges on the outside of the flukes and the flat surfaces of the band bonding and bracing the sides and the fluke faces, all have a guiding influence to cause the anchor to travel in a straight line in the same general direction in. which it has been started, after being dragged along the bottom. From experiments with these features of the invention, I have determined that, regardless of the position in which the anchor strikes the bottom or, in other words, is started on its path into the bottom, it will still travel in a downward direction. For instance, assuming that the anchor landed primarily among rocks, roots, etc., and was dragged with the flukes in a vertical position, in a groove as it were, it can be seen that the points of either fluke which are down will immediately dig into the bottom and go down, due to the guiding flanges on the outside face of the flukes; thus, in a soft bottom, the anchor will hold in a vertical direction as well as in a horizontal direction. This is not true with any conventional anchor provided with a stock or crowns for causing the anchor to take hold of the bottom surface.

Another important feature of the invention is the provision of an adjustable shear-pin, the purpose of which is to retrieve the anchor even though in use it is hopelessly fouled on the bottom and could not normally be pulled in or retrieved with any forward or vertical motion. In the case of the present invention, a stop on the shank limitsthe travel of the flukes to a normal 30 operating angle from the center line of the shank. In other words, as long as the anchor is dragged ahead by the shank, the maximum exerted pull is between the shank and the cross-bolt or the axis of the movement between the shank and the flukes. Thus, the shear-pin normally has a relatively tinually dig down and maintain the 30 angle, whichis limited as by contact of a Y-shapedextension on the bot tom of the shank. For example, assuming that the anchor was lodged under a root or rock with a forward pull, as would be normal in arresting the drag of a vessel from the force of either the tide or wind; thus the general direction of the cable attached to the anchor would be normal, with the points of the flukes being held down by a:

forward pull on the anchor shank. Assuming now that the anchor is to be retrieved and the shank is raised until,

the cable is in nautical terms up short 'or vertical, with the points of the flukes caught by some obstruction, the pressure on the shear-pin then becomes abnormal. Since it is constructed of dimensions and materials which can be broken by a predetermined abnormal strain directly away from the points of the flukes, this pull causes the end of an adjustable shear-pin to be sheared off and permits withdraw the boat usage, etc.

The facts that the anchor can be retrieved and that loss of ground tackle, including the anchor and cable, is prevented, are important features of invention. Furthermore, in the event of bad weather, where the anchor has been fouled and retrieved by use of the shear-pin method, it can be readjusted in a few moments and re-used by simply screwing in the shear-pin to another position, where it is again useful as a shear-pin without replacement.

In the preferred form of my anchor, fiat M- shaped fluke points are provided with guiding surfaces on the outer edge parallel with the shank. Also, in the preferred form, the area of the holding surface of the fiukes is divided on opposite sides of a through-bolt or axis, dividing the load on the surface which is balanced so that, by Weight, the points of the flukes when raised vertically will always remain parallel with the shank, thus dropping E sand, mud, etc.

Further, inverted V-shaped guiding surfaces on the outer edge of the M-shaped fiukes, which might be likened to the palms on the fiukes of an old-style stock anchor, perform an entirely different function; that is, they are parallel with the shank and when pulled through mud or sand they resist very little and serve to guide the flat surface of the flukes down deeper until a hold is taken finally in a relatively hard, stiff bottom, rather than on the surface of the bottom, as would be the case with an anchor that can be dragged and skidded or rotated on the soft, muddy surface of the bottom.

I have thus provided relatively wide bottom surfaces that tend to tip the points of the flukes down without materially adding to the resisting surface of the crosssection of the anchor. For instance, in the stamped form shown, fiat thin surfaces are shown as braces, to brace the parallel sides of the anchor to the fiukes. In the cast form, I have indicated with dotted lines that suitable fillets can be provided. In either case, the wide, flat rear portion or bottom edge of the guides or flanges will contact the bottom, and when the anchor is drawn ahead will have the same function as crowns; that is, to cause the points of the fiukes to rotate down. In this case, however, very little resistance is encountered, permitting the anchor to dig deeper than would be the case where crowns, stocks, or other extraneous material adding to cross-sectional area is added.

Another important feature of the anchor invention is that both fluke points are held in compression by the axis-bolt against spreading or distorting in use, normally bracing the side flanges by tension of the bolt and compression of the fiukes.

Another important feature is that any side pull on the fluke points is also braced against and resisted by the maximum metal thickness, which is at and below the point of shank attachment and pinioning of the flukes.

. Summarizing the above, the anchor is provided with guiding surfaces causing it to go down and be guided in a relatively straight line and is prevented from rotating or skidding by a relatively large area of guiding surfaces which have a comparatively small cross-sectional area. The actual holding area of the anchor is balanced by a bolt through the flukes and shank on which the weight of the anchor is balanced, so that the flukes will remain in a vertical position when the anchor is raised. Yet, when the anchor is on the bottom, the points of the fiukes and the area presented will be greater on the pointend of the flukes than on the bottom part below the axis, thus causing the anchor to always maintain a digging position when pulled along by the shank. The crosssectional area, while it is balanced, and the points of the flukes tend to travel away from the shank, reaches the limit when the Y-formed part on the bottom of the shank reaches a stop, thus limiting the digging angle of the flukes to approximately 30 away from the center line of theshank. M p 7 r The preferred form of the anchor, as shown on the drawings, has been described as stamping and spot-welded construction. It is to be understood that the novel design of the anchor also provides a very simple and suitable form to be manufactured from castings. In other words, the entire construction can be made from two simple castings wherein fillets are provided in place of the band at the bottom of the flukes and a hole is cored through the fiukes for the provision of a bolt or rivet to pivot the shank from the fiukes, as is indicated in the drawings. The anchor can be molded without the necessity of core boxes and completed from two simple castings, a stock core being used to provide the opening for the bolt or rivet through the flukes.

The invention includes many other objects and features of advantage, some of which, together with the foregoing, will appear hereinafter, wherein preferred forms of anchor construction are set forth and described in the drawings forming a part of this description and illustration.

tion of the fiukes Where they lie on a angle from the center line of the shank. Also in broken lines a portion of the flukes is shown swung back 135 from operational position on the bottom, when the shear-pin is broken.

FIG. 3 is a bottom view of the anchor of FIG. 1, indieating the flukes parallel with the shank and further illustrating the minimum cross-sectional area of the anchor in either the cast or stamped form. It further illustrates the bottom of the adjustable shear-pin and the bottom of the anchor.

FIG. 4 is a view in front elevation of a modified form of anchor also embodying the principles of the invention.

FIG. 5 is a view in vertical section through the anchor, taken along the line 55 in FIG. 4. The normal vertical position of the anchor is shown in solid lines, while 16 are bound with a-metalstrip 18 which serves to stiffen broken lines indicate a position where the shank is swung about 30 away from the center line of the fiukes, and an additional dotted line indicates a swing of the shank of for the purpose of pulling the anchor out backwards when the shear-pin is broken.

FIG. 6 is a bottom plan view of the anchor of FIG. 4. Broken lines indicate that the band on the bottom of the anchor can be made to completely surround the base of the anchor, if desired, to add weight or strength.

FIG. 7 is a fragmentary view in end elevation of the anchor of FIG. 4. A line X shows the plane of contact on the bottom, made by the points of the flukes and the crowns, which extend out beyond the base of the flukes on the bottom.

FIG. 8 is a fragmentary view in elevation of one of the stampings used in the anchor of FIGS. 4 through 7.

FIG. 9 is a fragmentary view in elevation and in section, taken generally along the line 9-9 in FIG. 8, with two stampings placed back to back and spot-welded together. Portions are broken away to save space.

Referring to. the drawings; in FIG. 1, a shank 10 is shown with a cable-attachment opening 11. The shank 10 is attached to twin fiukes 12 by a central axis-bolt 13, which is provided with nuts or riveted ends 14 to prevent the points 15 of the fiukes 12 from spreading during operation. Parallel flanges 16 are turned on the outer edges of the flukes 12, terminating at a point 15 on the upper end of the flukes and forming a wide T-shaped section 17. on the bottom edge of the anchor. The flanges thefianges 16 and also act as crowns to tipthe points-15 ofthe flukes' 12 down into the bottom when the anchor is laid flat thereon. Short flanges 19 are provided on the flukes 12 to space the bottom end 20 of the shank and to stiffen the flukes 12 at the bottom edge of the V between the flukes. The bottom end 20 of the shank 10 is also provided with a Y-formed wrench-like extension 21 which serves to contact the stop member 22, thus limiting the travel of the shank 10 relative to the flukes 12 to approximately a 30 angle on either side. (See FIG. 2.) The stop member 22 is an extension of an adjustable capscrew 23 which, when adjusted, is locked in the proper position by a lock-nut 24. The extension 22 of the capnut 23 becomes an adjustable shear-pin and stop member normally limiting the travel of the points of the flukes to a 30 digging angle and also providing, under abnormal conditions, a weak link or shear-pin, to permit the shank 10 to swing further than its normal working position of 30, as will be described later in connection with FIG. 2.

FIG. 2 is a partly sectional view taken on the line 22 of FIGS. 1 and 3, as indicated. 'Like reference characters are used throughout the description. It is to be understood that when the shank 10 is in a vertical posi tion, as shown in solid lines, the flukes will normally balance so that the points of the flukes 12 will remain parallel with the center line of the shank 10, for the reason that the weight of the material in the anchor is balanced so that the part below the axis of the central bolt 13 outweighs the material above the center of the axis, thus maintaining a normal vertical balance for the flukes. Thus, when the anchor is drawn up from the bottom, the points 15 of the flukes 12 come up parallel with the shank 10 and prevent hooking on the side of the hull or scratching same with the sharp points of the flukes. Furthermore, sand and mud is normally shed from the vertical surfaces more easily than is the case with conventional anchors. During normal operation, when the anchor lands on the bottom it normally lies flat and thus makes a four-point contact between the points 15 of the flukes 12 and the corners 25 of the band 18, enclosing the wide-flanged surfaces on the lower end of the flukes 12. Thus, as the anchor is drawn ahead by the ground tackle and shank 10, the points of the flukes are tipped down by the resistance of the wide end of the flanges 16 and corners 25, which serve in this case as crowns would on conventional anchors.

In other words, the effect of dragging the anchor ahead is that the resistance of the wide corners 25 on the flanges 16 and band 18 in contact with the ground surface rotates the fluke points 15 down into the sand or mud and thus causes the anchor to be drawn downward on a 30 angle into the bottom. The 30 angle is determined in shear-pin model anchors by the branch, wrench-like extension 21 and adjustable shear-pin point 22 which limits and controls the digging angle of the flukes 12 up to a certain limit, which, incidentally, is safely within the limits of the shearing strength of the point 22 of the pin and the shearing extension 26 on the point of the wrench-like extension 21 of the shank 10. In other words, as long as the dragging force is balanced by the area of the flukes above and below the pin, the shear-pin is only a stop means, limiting the travel of the points of the flukes. On the other hand, should the points of the flukes become fouled under a root, rock, etc., and the shank 10 of the anchor be pulled vertically, as would be the case with the anchor being hauled up short or the case of a powerdriven vessel being run backward against the rode of the anchor, then an abnormal strain is placed on the shearpin 22 by the points of the jaw 26, thus shearing it off and permitting the anchor to be pulled out backward and out from under the obstruction under which the points were hooked. After the anchor is recovered, the lock-nut 24 can be slacked and the cap-screw head 23 readjusted to provide a new point 22 for further operation, without the necessity of replacing the cap-screw 23 until such time as it has been used beyond its normal limit of usefulness. In larger models of the anchor, wherein the shear-pin feature is not desired, the jaws of the wrench-like formation are extended as indicated at 27 and are formed to fit onto the surface 28 to control and limit the digging angle of the points of the flukes 15.

FIG. 3 illustrates a bottom view of the anchor with the points of the flukes paralleling the center line of the shank. In the form shown, the flukes 12 are indicated as being made of sheet steel, sheet stainless steel, or other suitable material, and are shown as flat surfaces 12 with flanged parallel ribs on the outside, bound and supported by a continuous strip of metal, spot-welded to and completely enveloping both sides of the anchor, comprising at the center six thicknesses supporting the point of most strain; that is, where the forked shank stops against the shearpin 22 or laminated surfaces of the lowermost part 23 of the anchor. In the form shown, after the two identical fluke stampings are placed back to back, spot-welded, and bound with the band 18, I prefer to dip the assembled parts into a galvanizing bath; thus all of the interstices between the laminated material are filled with bonding metal, thus comprising a unitary structure of light weight and maximum strength for the weight of the material used in the construction of the anchor. After the fluke assembly is manufactured as described, I prefer to insert the shank and place the bolt 13 through the assembly, thus, with the nuts 14 or equivalent rivet heads, I provide a stress member, holding the assembly firmly together at the point of greatest stress, in a simple, economical, light weight construction.

Where a cast anchor is preferred, or for other reasons, it is to be understood that the same general design can be made by substituting fillets at the dotted line indicated at 30 and the elimination of the strip-metal band 18. The strips 18 could follow a similar path. The same general novel form and features of the invention can be produced in two very simple castings, which can be made without cores. For instance, the shank 10 can be cast finished, including the wrench on the lower end, the hole for the pin 13, and the hole 11 for the provision of ground tackle. In other words, this part can be cast without cores. Referring to the flanged flukes 12 and specifically to the bottom view shown in FIG. 3, fillets as indicated by the bottom lines 30 can be provided onthe pattern, substituting for the band 18 which, in cast form, will be eliminated. Thus, the pattern will be made in halves, a stock core will be provided for the axis-bolt 13, and the fluke assembly will be cast as a single unit without the use of core boxes; and thus two simple castings can be assembled by the insertion of a bolt 13 through the stockcored hole in the flukes and a sand-cast hole through the shank, providing a. completely cast anchor without the use of any machining whatsoever. In this case and for large anchors without the shear-pin feature, the bottom end 20 of the shank 10 could be provided with a Y-formed extension as indicated at 27, FIG. 2.

FIGS. 4 through 9 show a modified form of anchor 50, comprising fluke stampings spot-welded together, back to back, and galvanized after assembly and also embodying the principles of the invention, and in many ways similar to the anchor of FIGS. 1 to 3. A shank 51 has a cableattachment opening 52 and is attached to twin flukes 53 by an axis-shaft 54. In this instance, the stamped flukes 53 are formed to provide a cavity for the axis-shaft 54. Openings 55 are provided to simplify stamping procedure and to provide a vent opening to insure that galvanizing metal will completely fill the interstice between the axis shaft 54 and the stampings 53. This enables elimination of the nuts 14 outside the flukes in FIG. 1 and insures a thorough metallic bond between assembled parts.

, Parallel perpendicular flanges 60 are provided on the outer edges of each fluke 53 and terminate at the top at a point 61'. Again, the flukes 53 with their flanges 60 appear as a wide T-shaped configuration at the bottom edge of the anchor 50, as shown best in FIG. 6. The flanges 60 are preferably bound with a metal strip 62, which serves to stiffen the flanges 60 and also to help tip the points 61 of the flukes 53 down into the bottom mud when the anchor 50 is laid flat on the bottom. In this instance, it will be seen that the strips 62 exactly follow the contour of the flukes, instead of separating from them as in FIG. 3. These strips 62 may continue across the whole length of the flanges, as shown in the dotted-line portion 63, in FIG. 6.

The bottom end 64 of the shank 51 is also provided with a Y-shaped, wrench-like extension 65, which serves to contact a stop member 66, thus limiting travel of the shank 51 relative to the flukes 53. Preferably, an angle of approximatly 30 is the limit, as shown in FIG. 5. The stop member 66 and its breakable shear-pin or shank 67 are shown and described in another patent application, Serial No. 640,392, filed February l5, 1957.- When the shear-pin 67, which normally holds the stops 66, is broken, the shank 51 can swing around 135 to where it can be pulled out backward.

Once again, the anchor flukes 53 are preferably made from a pair of stampings 70 placed back to back, one of the stampings being shown in FIG. 8, and their backto-back placement being illustrated in FIG. 9. The pinion-bar or axis-bolt 54 is encased between the two stampings 70 that form the flukes 53, the openings between the matched holes 55 being formed by mated semi-cylindrical depressions.

FIG. 6 shows that the cross-section of the anchor 50 is very thin, which permits it to dig in with very little frictional resistance when the anchor 50 is drawn along by the shank 51. As FIG. 7 shows, the construction is quite smooth, with the strips 62 providing crowns 71 extending beyond the base of the flukes 53 on the bottom, the line-X indicating the plane of contact of the anchor when it lies on the bottom. -It will be noted that the fluke flanges 60 form generally triangular end sections, while the flukes 50 themselves are pointed in a general M-shape but, in this instance, with some curvature applied, along the upper edge 72 of the flukes 53.

As FIG. 8 shows, the stampings 70 that form the opposite sides of the flukes 53 are flanged not only on the outside at 60 but also on the inside at 73. The inside flanges 73 form a guiding surface with relatively large contact wearing-area for the shank assembly as it slides from side to side on the pinion-bolt 54, when the anchor 50 is in use. The pinion-bolt 54 itself holds the shank assembly to the flukes, being encased and welded in the half-circular formed section which, when two members are put together, forms the cylindrical opening 75. In assembly, the two stampings 70 are placed back to back and preferably spot-welded and then galvanized, thereby forming the housing for the pinion-bolt 54 and securing same with a metallic bond.

The present anchor gives full holding power and, also, five safety features. For one thing, there is instant digin through the lever action. Anchors that slide flat across the bottom are not able to bold, .but the anchor of this invention has two tripping-arms to forcethe flukes 53 in and then to pull themstraight. The side, guides ,or flanges 60 also form anti-rotation means which prevent the rotation or corkscrewing of the anchors, an action. that tends to pull them out again after they take hold. The side flanges 53 make the anchor pull down straight and level.

The anti-snag release feature enables the anchor to be pulled out when the shear-pin 67 breaks, without having to worry about the pin 67 breaking under normal. pull.

- The flukes 53 do n t flop. The anchor 50 is sobalanced that the flukes 53 stand straight up, when it is hoisted or carried, and do not stick out where they can catch apersbn in -the legs. There is no stock of the conventional kind, with rods that stick out from the side to" trip a man who is carrying the anchor as-when bringing it aboard or laying it on the deck.

I'Ih a'nchoral'so has noside-wall obstructions; so. mud slides off when the anchor is hoisted.

From the foregoing it is understood that the novel features of the invention are adaptable to either fabrication in sheet steel, etc., or sand casting, die casting, etc., providing new and novel features in anchor construction and manufacture, and bringing about new uses and features of anchors not heretofore known or used.

Therefore, having described my anchor in its preferred form, what I claim is:

1. An anchor comprising a shank, twin flukes each formed of a pair of metal stampings, said flukes being arranged in the general form of the letter M and having tapered parallel flanges at their outer edges, said flanges terminating at points at the upper end of the flukes and widening from said points at an approximate 35 angle to a total bottom width approximately 50% of the length of said flukes, said stampings provided with elongated transverse semicylindrical portions forming a cylindrical bearing up approximately 20% of the distance from the bottom of said flukes, the metal stampings of each of said pairs being fastened back to back, and a bolt attached to one end of said shank and pivotally mounted in said bearing.

2. An anchor comprising a vertical shank, twin flukes pivotally attached to said shank and each formed of a pair of metal stampings that are T-shaped in horizontal cross-section to provide parallel flanges at their outer edges and flat vertical portions between said shank and said flanges, said flanges tapering up to points at the upper end of the flukes, the upper edge of the said flat vertical portions having sharp points at and being highest at their intersection with said flanges and sloping down to a low portion where they lie closest to said shank.

3. The anchor of claim 2 wherein the pivot line of said flukes lies at a distance of about 20% from. the bottom of said flukes toward the top.

4. An anchor comprising a shank, twin flukes each formed of a pair of metal stampings fastened back to back, the outer and upper edges of said flukes describing the general form of the letter M, said flukes having tapered parallel flanges at their outer edges terminating at points at the upper end of the flukes, said flukes being pivotally attached to one end of said shank and a metal band surrounding said fluke stampings and their flanges and reinforcing them.

5. An anchor comprising a shank, twin flukes pivotally mounted to said shank and arranged with outer and top edges in thegeneral form of the letter M and having tapered parallel flanges at their outer edges, said flanges terminating at points at the upper end of the flukes and widening from said points to a wide bottom, and serving as parallel guides for said anchor, the bottom portion of said flukes being heavier than the upper portion for aiding in rotating said flukes down when said anchor is dragged on the bottom, and stop means to limit the movement of said flukes relative to said shank;

6. An anchor comprising a shank, twin flukes having outer and upper edges describing the general form of the letter M and tapered parallel flanges at their-outer edges terminating at points at the upper end of the flukes, said flukes being pivotally attached to one end of said shank, and a metal band surrounding said fluke stampings and their flangw and reinforcing them.

7. An. anchor comprising a shank, flukes each formed of a pair of. metal stampings fastened back to back-and shaped to provide a horizontal lengthwise opening between them, the outer and upper edges of said flukes describing the-general form of the letter M, said flukes having tapered parallel flanges at their outer edges terminating at points at the upper end of the flukes, and a shaft in the opening between said metalstampingsand pivotally attaching said flukesto one endof saidshank.

8."An anchor comprising a shank, twin flukes with outer and upper edges describing the general form of the letter M, said flukes having tapered parallel flanges at their .ourter'edges terminating at points at'the upper end of the flukes, said flukes being pivotally attached to one end of said shank, said shank being provided with an inverted Y-formed section on its lower end that serves as stop means, a threaded member threaded up from the bottom of said flukes and projecting up above them into the area defined by said Y--formed section, said Y-formed section limiting the travel of the flukes to about 30 on either side of center.

9. The anchor of claim 8 wherein said threaded memher is considerably overlength so that if its projecting end 10 is broken ofi, it can be threaded further up and used again.

References Cited in the file of this patent UNITED STATES PATENTS Clark May 23, 1894 Baldt Oct. 27, 1896 Fearn Dec. 6, 1949 Parks Jan. 17, 1956 FOREIGN PATENTS Great Britain of 1892

Images