US3045839A

US3045839A - Apparatus for handling boats

Info

Publication number: US3045839A
Application number: US701618A
Authority: US
Inventors: Frederick H Hibberd
Original assignee: Individual
Current assignee: Individual
Priority date: 1957-12-09
Filing date: 1957-12-09
Publication date: 1962-07-24
Anticipated expiration: 1979-07-24

Description

July 24, 1962 F. H. HIBBERD 3,04

APPARATUS FOR HANDLING BOATS Filed Dec. 9, 1957 2 Sheets-Sheet 1 {ASL/KM 5g 4 ATTORNEY July 24, 1962 F. H. HIBBERD APPARATUS FOR HANDLING BOATS 2 Sheets-Sheet 2 Filed Dec. 9, 1957 ATTORNEY States Unite atent fire 3,045,339 APITARATUS FOR HANDLING BOATS Frederick H. Hibberd, 875 Forest Ave., Rye, N.Y. Filed Dec. 9, 1957, Ser. No. 701,618 3 Claims. (Cl. 2141) My invention relates to boat handling equipment, and is especially concerned with a lifting cradle which may be employed for transportation of a boat and to lower and set the boat afloat and lift it from the water.

In order to lower and lift a boat into and out of the water, it has been the practice heretofore to employ slings placed directly about the hull of the boat by divers. This is an objectionable practice because the slings so placed often slip and inadequate protection is provided against the collapsing forces which are produced by the slings when they are under tension and carrying the dead-weight load of the boat.

It has also been the practice heretofore in some instances to lower a boat into the water with the boat in a conventional wooden cradle to which slings are connected. The use of a conventional wooden cradle is objectionable also, however, because of its excessive buoyancy and not being readily removable from the boat once it is afloat. In order to sink a conventional wooden cradle, it usually is necessary to weight it, and it must be virtually destroyed in order to remove it from the boat when the boat is afloat. Furthermore, a conventional wooden cradle is useless for lifting a boat from the water because it cannot be positioned about the boat and assembled therewith while the boat is afloat.

An object of my invention is to provide a boat lifting cradle which, without any auxiliary equipment or the services of a diver, can be readily secured to and detached from a boat while the boat is afloat.

Another object of the invention is to provide an improved boat lifting cradle which may be employed as a transportation cradle in which a boat is firmly secured and protected from collapsing forces while being lifted and lowered from place to place.

A still further object of the invention is to provide a boat lifting cradle which can be readily disassembled for convenient transportation from place to place when not in use.

A still further object of my invention is to provide an improved boat lifting cradle which is of simplified construction.

Further objects and advantages of my invention will become apparent as the following description proceeds, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

In the drawings, FIG. 1 is a View in elevation of a boat which is afloat in water and t which is secured a lifting cradle embodying my invention, the view of the cradle being taken at line 11 of FIG. 2; FIG. 2 is a transverse elevation View, taken at line 2-2 of FIG. 3, of the boat and lifting cradle shown in FIG. 1; FIG. 3 is a reduced sectional view taken at line 33 of FIG. 2; FIG. 4 is an enlarged fragmentary top plan view of a corner of the lifting cradle shown in FIG. 1 and FIG. 2 to show details more clearly; FIG. 5 is a fragmentary sectional view taken at line 5-5 of FIG. 4; FIG. 6 is an enlarged fragmentary elevation view of a part of the construction shown in FIGS. 1, 2 and 3; FIG. 7 is a horizontal sectional view taken at line 7-7 of FIG. 6; FIG. 8 is an enlarged fragmentary view, partly in section, of another part of the construction shown in FIGS. 1, 2 and 3; and FIG. 9 is a horizontal sectional view taken at line 9-9 of FIG. 8.

Referring to FIGS. 1 and 2, I have shown my invention in connection with a boat 10 having a hull 11 provided with a keel 12, the boat being diagrammatically illustrated as being afloat in water with the Water line at 14.

In accordance with my invention, I provide an improved lifting cradle 15 which can be readily secured to the boat 10 and detached therefrom While the boat is afloat in the water. The lifting cradle 15 comprises four upright members 16 Whose lower ends are connected at 17 to the corners of a bottom rectangular frame which includes spaced apart cross members 18 transverse to the keel 12 and members 19 connected thereto which extend lengthwise of the keel. The upper ends of the upright members 16 are connected at 20 to the corners of a top rectangular frame which includes cross members 21 disposed above and transversely of the hull 11 and members 22 connected thereto which extend lengthwise of the hull. Stated another way, the lifting cradle 15 comprises a pair of spaced apart upright end frames, one of which is illustrated in FIG. 2, connected by the members 19 and 22 which extend lengthwise of the boat 10.

As seen in FIG. 2, each end frame includes a pair of inclined reinforcing members 23 which are connected at 24 and 25 to the

members

16 and 18, respectively; and additional bracing members 26 connected at their upper and lower ends of the inclined members 23 and bottom frame members 18 at 27 and 23, respectively. The bottom frame includes reinforcing members 29 which are at an acute angle with respect to the members 19 and are connected at 2911 and 29b to the spaced apart transverse members 18 as shown in FIG. 3. As seen in FIGS. 1 and 2, the sides of the cradle are provided with members 32 which cross one another. The members 32 are secured together at 33 and their upper and lower ends are secured at 34 and 35 to the upright members 16.

As best shown in FIGS. 1 and 2, the bottom transverse members 18 are hollow and of cylindrical form for reasons that will be described presently. A pair of flat plates 36 is fixed in any suitable manner to the bottom of each transverse member 18, such plates serving as feet or bearing surfaces for the lifting cradle when the latter is resting on a supporting surface. To the top of each transverse member 18, at a region intermediate the ends thereof, is also fixed a flat plate 37 upon which the bottom of the keel 12 is adapted to rest.

At the region the upper ends of the members 25 are connected to the diagonal members 23, the latter are provided with pads or wooden blocks 38 or the like in Which the hull 11 snugly iits when the keel 12 is resting on the flat plates 37.

The top horizontal frame of the cradle 15 includes corner brackets 39, each of which comprises a pair of similar triangular-shaped plates 44 and 41 disposed one above the other and fixed, as by welding, for example, to a hollow sleeve 42 which receives the upper end of an upright member 16. The plates 4% and 41 are in spaced apart relation, the top plate 40 overlying the upper end of the sleeve 42 and forming a cap therefor, and the bottom plate 41 having an opening through which the sleeve 42 extends. The upper end of the upright member 16 extends within the sleeve 42 for the full length thereof and is fixed thereto at 43 in any suitable manner.

The ends of the members 21 and 22 are formed with flat apertured ears 44 and 45 which are detachably connected at 46 and 47, respectively, between the spaced apart plates 40 and 41 of the corner brackets 39, as best shown in FIGS. 4 and 5. Each corner bracket 39 is provided with a suitable strap 48 which is fixed to the top plate 40 thereof, the straps forming loops, as best shown in FIG. 5. As seen in FIG. 1, the straps 48 are employed to attach the cradle 15 to a sling 49 which in turn may be raised or lowered and moved from place to place with the aid of a hoist 50.

In order to secure the boat 10 firmly in the cradle 15, each of the upright members 16 is provided with a clamp 51 having a clamping screw 52 adapted to engage a part 53 at the upper part of the hull 11, as seen in FIG. 2. The clamp 51, which is shown more clearly in FIGS. 8 and 9, includes

semi-circular sleeves

54 and 55 which .are detachably secured at 56 to the upright members 16. The semi-circular sleeve 54 is provided with an apertured arm 57 which threadedly receives the clamping screw 52 which has a handle 58.

When the boat is properly positioned in the cradle 15, the lower end of the clamping screw is located in an opening 59 formed in the part 53 at the upper part of the hull 11. For example, the part 53 may be a block of hard wood or steel set in the gunwale 6t and shaped around the rail of the boat 10, as illustrated in FIGS. 8 and 9.

So that the lifting cradle may be secured to and disconnected from the boat 10 with facility when the boat 10 is afloat in water, the cradle is provided with a number of buoyancy tanks 61. As best shown in FIGS. 6 and 7, each buoyancy tank 61 is in the form. of an upright air-tight cylinder which is formed of metal and provided with

brackets

62 and 63 of semi-circular form at the top and bottom parts thereof, respectively. The opposing sides of each bottom bracket 63 are notched at 64 to receive the opposing ends of a pin 65 which passes through the upright member 16 and is fixed thereto as by welding, for example. The opposing sides of each top bracket 62 are apertured to receive a threaded bolt 66 which passes through the upright member 16 and is adapted to receive a tightening nut 67. When a buoyancy tank 61 is attached to an upright member 16, the bracket 63 is first fixed to the pin 65 and thereafter the top bracket 62 is connected to the member 16 by the bolt 66 and tightening screw 67.

When the lifting cradle 15 is disposed about the boat 10 in the manner illustrated in FIGS. 1 and 2, the boat is firmly secured in the cradle and the latter forms an excellent transportation cradle for the boat. The cradle 15 is of rugged construction and may be formed of piping and angle members of lightweight metal such as aluminum, (for example, thus providing a lifting cradle for the boat which will effectively withstand all collapsing forces to which it normally will be subjected during lifting and lowering from place to place and will protect the boat during transportation thereof on a deck of a larger vessel if rolling or other movement of the vessel develops. At the same time, the lifting cradle 15 will be light enough so that it may be rendered buoyant when desider, as explained above and as will be described more fully hereinafter.

When the boat 10 is out of the water and being carried in the cradle 15, the plates 36 on the transverse members 18 form fiat bearing surfaces or feet which serve as regions at which the boat and cradle are effectively supported on a whanf or deck of a vessel or other place. The plates 36 afford protection to the transverse cradle members 18. In FIGS. 1 and 2 it will be seen that the keel 12 rests on the plates 37 which are fixed to the transverse cradle members 18, and the sides of the hull rest and bear against the blocks 38 which may be formed of wood and shaped to conform to the sides of the hull.

The boat 10 is firmly secured in an upright position in the cradle by the clamps 51 which, as best seen in FIGS. 8 and 9, prevent the boat from shifting from its fixed upright position in the cradle. When the boat is being stored or transported from one place to another, the buoyancy tanks 61 may be removed from the cradle 15 so that the likelihood of damaging the tanks 61 will be avoided.

When it is desired to set the boat 10 afloat in water, the sling 49 of the hoist 50 is fastened to the loops formed by the sraps 48 at the top corners of the lifting cradle 15. At this time buoyancy tanks 61 may be secured to the upright members 76 in the event they have been removed from the cradle 15 during transportation of the boat 10. The hoist 51! on the vessel is then manipulated to lift the cradle 15 and boat 10 carried therein to a point clear of the vessel and thereafter lower them into the water together.

With the boat 11) fioating in the water, the lifting cradle 15, which also is partly submerged in the water, may be detached therefrom by removing the top transverse members 21 and disconnecting the clamps 51 from the gunwale blocks 53. To this end the handles 53 of the clamping screws 52 are turned to effect axial movement of the clamp arms 57 on the screws. Since the weight of the lifting cradle 15 holds the screws 52 in position in the openings 59 in the blocks 53, turning movement of the screws 52 in the proper direction imparts downward movement to the clamp arms 57. After a predetermined downward movement of the clamp arms 57 on the screws 52, the lifting cradle 15 will move downward sufficiently so that it floats in the water in a partially submerged position with the wooden blocks 38 and fiat plates 37 removed a few inches from the hull 11 and keel 12, respectively. When this occurs, the lower ends of the screws 52 no longer are held fast in the openings 59 in the gunwale blocks 53 and the clamp connections 56 may be loosened to shift the clamps 51 to positions from those illus* trated in FIG. 2, so that all parts of the cradle 15, including the clamps 51, are clear of the boat 10.

As is well known, the lifting cradle 15 will be buoyed up by a force equal to the weight of the liquid which it displaces. Although I do not wish to be limited thereto, the major part of the buoyant force in the embodiment illustrated is developed by the main structural members 18 which are hollow and of cylindrical form and located at the bottom part of the cradle. With the hollow cylindrical members 18 at the bottom part of the lifting cradle 15, the major part of the buoyant force is developed at a region below the center of gravity of the cradle.

Assuming for the moment that practically all of the buoyant force on the lifting cradle is developed by the hollow members 18 and the cradle 15 shifts from a vertical position of equilibrium, a couple will be formed that will tend to capsize the cradle because the metacenter will be below the center of gravity. In the embodiment illustrated, the buoyancy tanks 61 provide suflicient buoyancy at the water level, at a region above the center of gravity of the cradle, to counteract and offset the unstable condition of the cradle 15 when it is disconnected from the boat 10. By selecting buoyancy tanks 61 of the proper size and shape, the tendency of the cradle 15 to capsize can be effectively controlled and the likelihood of the cradle turning over is Prevented.

In addition to maintaining the lifting cradle 15 in a stable upright position under operating conditions normally encountered when the boat 10 is set afloat in the water, the buoyancy tanks 61 are effectively employed to provide adequate buoyancy to control and regulate the distance the cradle 15 will sink into the water when being disconnected from the boat. In practice I have discovered that the vertical distance the lifting cradle 15 desirably should move downward from the position shown in FIGS. 2 and 8 need not be more than a few inches. This vertical distance may be slightly less than the distance h in FIG. 8 and may be reached after the screw 52 has been turned sufficiently to permit the clamp arm 57 to move axially downward to a level at the vicinity of the gunwale block 53.

After the cradle 15 has been separated from the boat 10 and is floating in the water at such a level that hull 11 and keel 12 are clear of the wooden blocks 38 and supporting plates 37, respectively, the cradle 15 and boat 10 can be moved apart with respect to one another, and, after the top transverse members 21 are again connected to the corner brackets 39, the cradle 15 can be lifted out of the water with the aid of the sling 49 and hoist 50 and again positioned on the deck of the larger vessel or wharf from which it was originally moved to set the boat afloat. If desired, the buoyancy tanks 61 may be removed from the cradle 15 before the boat 19 and the cradle are lifted but of the water.

When the boat is afloat and it is desired to lift the boat out of the water with the aid of the lifting cradle 15, the latter is lowered into the water to its floating position and the top transverse members 21 are removed from the cradle, after which the boat and cradle are moved toward one another until the cradle is disposed about the boat and the clamps 51 are at the vicinities of the gunwale blocks 53. It will be understood that the lifting cradle in its floating position is at such a level in the water that a clearance of a few inches is provided between the cradle parts and the boat, which enables the boat to be positioned within the cradle. When the clamps 51 are at the vicinities of the gunwale blocks 53, each clamp arm 57 is turned 180 from an outwardly extending position to the inwardly extending position shown in FIGS. 8 and 9 and firmly secured in position on the upright member 16 with which it is associated.

The lifting cradle and boat are then manipulated to position the lower ends of the clamping screws 52 in the openings 59 in the gunwale blocks 53, after which the screws 52 are turned by the handles 58 to move the clamp arms 57 upwardly with respect to the gunwale blocks 53. In this way, the cradle 15 is moved upwardly, and, when the keel 12 is resting on the plates 37 and the hull 11 is snugly fixed in an upright position between the blocks 38, the cradle 15 is firmly secured to the boat 10 and thereafter the top transverse members 21 are connected to the corner brackets 39. The lifting cradle and boat may be raised as a unitary structure from the water with the aid of the sling 49 and hoist 50.

While the cradle 15 is being raised by turning the clamping screws 52, the cradle is always being buoyed up by a force which decreases slightly as the cradle is being raised vertically the few inches to bring the plates 37 and blocks 38 thereof against the keel 12' and hull 11, respectively. Accordingly, the screws 52 do not support the entire weight of the cradle as it is being raised in the water, and, when the cradle is in its uppermost position shown in FIG. 2, the load on each clamp 51 will be relatively small, in the neighborhood of fifty to one hundred pounds clamp, for example.

The lifting cradle 15 is rigid and serves to protect the boat 10 from collapsing forces and to prevent shifting of the boat when it is being lifted or lowered therein. Accordingly, top transverse members 21 and other structural parts of the lifting cradle 15 form a spreader system which is capable of withstanding collapsing forces and preventing those forces from being transmitted to the boat 10. When the boat 10 is being raised or lowered in the lifting cradle 15, forces are transmitted from the cradle to the boat at preselected regions which serve to secure the boat firmly in the cradle and properly locate it therein, and, by reason of its construction, the cradle 15 itself withstands and does not transfer to the boat the collapsing forces which would be apt to injure the boat.

After a boat has been set afloat in the water with the aid of the lifting cradle 15, it is often necessary to transport the cradle for the purpose of removing the boat from the water at another point. Since the cradle 15 is formed of structural members which can readily be disconnected from one another, the cradle can be conveniently taken apart and shipped in a relatively small bundle. The cradle 15 is so constructed that all of the members thereof are removably connected to one another, as by bolts and tightening nuts, for example, whereby all of the members may be disconnected from one another to provide one or more bundles of pipes and structural members. By forming the cradle members of lightweight metal, such as aluminum, the weight of the bundle or bundles of members will be at a minimum, thereby reducing the cost of shipping the disassembled cradle parts.

In view of the foregoing, it will now be understood that I have provided an improved lifting cradle 15 of simplified construction which may be employed as a transportation cradle for the boat 10 and to lower and lift the boat into and out of the water. The cradle 15- also provides a stable support for the boat during lifting and lowering of the boat from place to place.

When the boat 10 is firmly secured in the lifting cradle 15 and being raised or lowered by the sling 49 which is under stress, the latter should be positioned vertically over the center of gravity of the boat. In addition to protecting the boat from collapsing forces produced when the boat and cradle are being'transferred by the sling 49, the arrangement of the top transverse members 21 and clamps 51 at the upper part of the cradle properly secures the boat in position with respect to its center of gravity.

Since the lifting cradle 15, when it is disconnected from the boat 10, will float in the water in such a partially submerged position that all parts of the cradle are clear of the boat, the cradle can be safety removed from and subsequently fixed to the boat without the need of any auxiliary equipment or the services of divers. In order to reduce the overall weight of the cradle 15 and the boat when the latter is being lifted from the water, the buoyancy tanks 61 may be disconnected from the cradle immediately after the cradle has been fixed the boat 10.

While I have shown "and described a single embodiment of my invention, it will be apparent that modifications and changes may be made without departing from the spirit and scope of the invention, as pointed out in the following claims.

What I claim is:

1. In combination with a vertically movable sling for setting a boat afloat and lifting it from a body of water, the boat having a hull and a center keel depending therefrom, a cradle of U-form having a bottom frame and spaced side frames forming a unitary structure which is adapted to be positioned about the bottom and sides of the boat at a place between the ends thereof, the bottom frame including spaced rigid members extending transversely of and across the bottom of the cradle and means including rigid members which extend lengthwise of the cradle and connect the transverse members to brace the bottom frame, each side frame including a pair of spaced upright rigid members which are connected at their lower ends to the bottom frame, and rigid members which extend lengthwise of the cradle and are connected to brace the upright members, means including rigid members which extend transversely of the cradle and are inclined to the vertical and connected to the bottom frame and to the upright members intermediate their ends to brace the side frames, the upright members and inclined members at opposing sides of the cradle being substantially opposite one another with the inclined members sloping downward toward one another, pads fixed to the inclined members intermediate their ends and against which the hull of the boat snugly fits when the keel rests on the bottom frame, a plurality of clamp arms, means for detachably fixing each of the clamp arms to a different one of the upright members at a region above the point the inclined member is connected thereto, each of the clamp arms being angularly movable on its upright member and vertically adjustable thereon, means on each clamp arm which is vertically adjustable thereon and movable to engage the upper part of the hull to firmly secure the boat in the cradle against the pads and the bottom frame, means at the upper part of the cradle for attaching the sling thereto, hollow parts, and mounting means for mounting the hollow parts on the upright members to develop buoyant force above the center of gravity of the cradle when the latter is afloat in the body of water.

2. Apparatus as set forth in claim 1 in which several of the rigid members are hollow, at least some of the rigid hollow members being at a region below the center of gravity of the cradle.

3. Apparatus as set forth in claim 1 which includes a top horizontal frame for the cradle, means for removably securing the top frame to the upper ends of the upright member of both side frames, the top frame comprising unitary structure including spaced rigid members which extend transversely of and across the cradle and rigid members which extend lengthwise of the cradle, and parts at the corners of the top horizontal frame forming the means at the upper part of the cradle for attaching the sling thereto.

References Cited in the file of this patent UNITED STATES PATENTS Vaughan Aug. 7, Stoelt Mar. 1, Crooks Aug. 13, Andrews Jan. 13, Bitte May 2, Weeks June 9, Livermon Nov. 7, De Groot I May 8, Livermon July 7, Henney Aug. 27,