US3111696A

US3111696A - Life buoy

Info

Publication number: US3111696A
Application number: US93181A
Authority: US
Inventors: Lo To
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-03-03
Filing date: 1961-03-03
Publication date: 1963-11-26
Anticipated expiration: 1980-11-26

Description

TO LO Nov.--Z6, 1963 LIFE BUOY Filed March 3, 1961 INVENTOR. L 0 7'0 A TTORNEVS United States Patent Uffice 3-,! 1 1,695 Patented Nov. 26, 1963 3,111,696 LIFE BUOY To Lo, Kowloontong, Kowloon, Hong Kong, assignor t Cheoy Lee Shipyard, Ngau Chi Wan, Kowloon, Hong Kong, a co-partnership Filed Mar. 3, 1961, Ser. No. 93,181 8 Claims. (Cl. 9-340) This invention relates to buoyant materials and more specifically to improved life buoys.

It is a principal object of this invention to provide a life buoy having high ratios of its strength and its buoyancy to its weight.

It is another object of the invention to provide such a life buoy which is rigid and very durable and which retains its high strength to weight ratio and buoyancy to weight ratio even after substantial abuse.

It is another object of the invention to provide such a strong and rigid life buoy which is substantially impermeable to water so that it may be used in water for indefinite periods of time without reducing its buoyancy.

It is another object of the invention to provide such an improved life buoy which is pleasing in appearance and which is very resistant to the elements and retains its pleasing appearance after substantial periods of exposure to the elements.

Other objects and advantages will become apparent from the following description read in conjunction with the attached drawings in which:

FIG. 1 is a plan view of an improved life buoy constructed in accordance with the principles of this invention;

FIG. 2 is a cross sectional view of the life buoy of FIG. 1 taken along the plane indicated by the line and the arrows at 2-2 of FIG. 1, and

FIG. 3 is a cross sectional view similar to FIG. 2 showing an alternative form of construction of the life buoy of this invention.

Referring now in detail to the drawings and particularly to FIG. 1, the life buoy illustrated therein comprises a buoyant body indicated generally by the arrow which has the general shape of a tore. The body 10 is surrounded by a grab line 12 which is attached to the body 10 by four cleats 14 to be described in greater detail hereinafter.

As best illustrated in FIG. 2, the body 10 is constructed of a pair of complimentary generally frusto-

toric shells

16 and 18. As indicated in 'FIG. 2, the term frustotoric is employed herein to define the shape bounded between one-half of a tore and a generally central plane perpendicular to the axis of the tore. The

shells

16 and 18 are constructed of a rigid and water-impermeable plastic, preferably fiberglass matting impregnated with a polyester resin. Suitable polyester resins for this purpose are the rigid cross-linked resins known to the art produced by copolymerizing styrene and an unsaturated polyester such as polyethylene glycol maleate and the like.

Mounted inside of each of the

shells

16 and 18 is a quadrant chock of wood 24 with each chock 20 positioned under one of the cleats 14. The outer surfaces of the chocks 24 are shaped to conform to the inside surface of the

shell sections

16 and 18 and are cemented to such inner surfaces by means of a layer of a suitable bonding material such as the above-mentioned polyester resins. The remainder of the cavity inside each of the

shell sections

16 and 18 is filled with a generally rigid and substantially

impermeable body

22 and 24 respectively of plastic foam. The convex surfaces of the

bodies

22 and 24 are bonded to the inner surface of the

shell sections

16 and 18, respectively, by a suitable bonding material such as the above-mentioned polyesters. The surfaces of the

bodies

22 and 24 adjacent to the wood chocks 20 are also bonded to the chocks 26 by such materials.

A preferred material from which the

bodies

22 and 24 of plastic foam are fabricated is generally rigid polyurethane foam which is cellular in nature with the cells of the body unconnected so that the mass of plastic foam is impermeable.

The two

shell sections

16 and 18, with their bodies of

plastic foam

22 and 24 contained therein, are rigidly attached together by a layer 26 of rigid material bonded on its opposite sides to the flat sides of the

plastic foam bodies

22 and 24 and to the edges of the

shell sections

16 and 18. This bonded seam 26 is constructed to impart rigidity to the life buoy along its central plane perpendicular to its toric axis. In this regard it should be noted that this central seam is preferably formed of a layer of fiberglass matting impregnated with the abovementioned polyester resins.

The four metal cleates 14 mentioned above are attached to the periphery of the life buoy at equal intervals therearound by means of wood screws 28 screwed through the

shell sections

16 and 18 and into the quadrant wood chocks 20. In this manner the cleats 14 are securely anchored to the life buoy. The cleats 14 and wood screws 28 are preferably made of chrome-plated brass which gives the life buoy a pleasing appearance and which are resistant to corrosion.

In the alternative form of the life buoy of the invention which is ilustrated in FIG. 3 the

plastic foam bodies

22 and 24 are provided with frusto-

toric cavities

30 and 32 therein which together define a toric void in the assembled life buoy. The surfaces of the cavities 3t and 32 are covered with a layer of fiberglass and polyester resin bonded thereto which effectively seals the walls of the cavities and which provides additional strength and rigidity of the life buoy both in a direction perpendicular to the axis of the life buoy and in a direction parallel to its axis.

The life buoy of this invention may be constructed very efficiently by (1) molding fiberglass and polyester resin into the shape of the

shell sections

16 and 18, (2) mounting the quadrant wood chocks 20 in place with their outer surfaces bonded to the inner surfaces of the

shell sections

16 and 18, (3) placing the

bodies

22 and 24 of plastic foam material in place in the

shell sections

16 and 18 and bonding the convex surfaces of the

bodies

22 and 24 to the

shell sections

16 and 18, (4) applying a layer of fiberglass and polyester resin to the flat face of either half of the life buoy (and applying the fiberglass polyester coating to the surfaces of the cavities 30 and 32), (5) bringing the two halves of the life buoy together in complimentary relation to define the completed body 1%) of the life buoy prior to hardening of the resin applied in step 4, and (6) attaching the cleats 14, with the grab line 12 therein, to the wood chocks 20 by means of the screws 28. Preferably the skin of the life buoy is then coated with a fiameproof polyurethane paint which gives the surface of the life buoy a high gloss and enhances the hardness and water resistance of the surface.

With the life buoy constructed in accordance with the embodiment of FIG. 2 and having a diameter of thirty inches and major and minor axes of the toric section of six and three inches respectively, the life buoy weighs eight pounds, has a buoyancy capacity of 1,107.74 cubic inches equivalent to forty pounds in fresh water and a floating capacity of thirty-two pounds in fresh water. The hollow body construction of FIG. 3 having similar dimensions and a sectional area of 14.69 square inches weighs six and one-half pounds, has a similar buoyancy capacity, and a flotation capacity of thirty-three and onehalf pounds in fresh water.

While two embodiments of the present invention have been illustrated and described in detailherein, it is obvious that many modifications in the construction and arrangement of parts and the choice of materials may be made without departing from the spirit and scope of the invention.

1. A generally rigid life buoy which is impermeable to water and has high ratios of its strength and its buoyancy to its weight which comprises a shell of generally toric shape formed of a rigid water impermeable plastic and a body of generally rigid and substantially impermeable plastic foam mounted in said shell with the outer surfaces of said body bonded to the inner surfaces of said shell, said body providing substantially rigid connection between opposite wall portions of said shell throughout a substantial part of the sectional area of said life buoy, said life buoy being characterized further by the inclusion of a plurality of wooden chocks mounted in said shell adjacent to and spaced around the periphery of said shell, the outer surfaces of said chocks being bonded to the interior surfaces of said shell, a grab line encircling said life buoy, a plurality of metal cleats holding said grab line to the periphery of said shell, and a plurality of screws extending through said cleats and said shell and anchored in said wooden chocks.

2. A generally rigid life buoy which is impermeable to water and has high ratios of its strength and its buoyancy to its weight which comprises a pair of complementary shells of generally frusto-toric shape formed of a rigid water impermeable plastic, a body of generally rigid and substantially impermeable plastic foam mounted in each of said shells and having a generally convex surface bonded to the concave surface of said shell and a generally flat surface portion lying along the flat side of said shell, and a layer of generally rigid plastic bonded on opposite sides thereof to said generally flat surfaces of said bodies and securing said bodies and shells together in a generally toric shape.

3. The improved life buoy of claim 2 in which a plurality of wooden chocks are mounted in each of said shells positioned adjacent to one of said chocks in the other of said shells; a plurality of metal cleats are pro vided around the periphery of said life buoy with each cieat having an end thereof positioned above one of said chocks in each of said shells, and a plurality of screws are provided extending into said shells and attaching said ends of said cleats to the chocks thereunder.

4. The improved life buoy of claim 3 in which a grab line is provided surrounding said life buoy and extending 4 between said cleats and said life buoy intermediate of said ends of said cleats.

5. The improved life buoy of claim 2 in which said bodies of plastic foam together with said layer of generally rigid plastic define an interior supporting structure extending continuously between said shells.

6. The improved life buoy of claim 2 in which each of said bodies of plastic foam is provided with a generally frusto-toric cavity therein whereby said bodies in assembled relation define a generally toric cavity in said life buoy.

7. The improved life buoy of claim 6 in which a generally rigid and water impermeable plastic coating is provided along the walls of said cavity, and said coating is bonded to said layer.

8. The method of making a life buoy which comprises: forming a pair of generally rigid and water impermeable plastic shells having complementary generally frustotoric shapes, forming a plurality of wooden chocks shaped to fit in said shells at peripheral positions therein, placing said chocks in said shells at said peripheral positions and bonding a surface portion of each of said checks to one of said shells, forming a pair of complementary bodies of generally rigid and water impermeable plastic foam shaped to fill substantially the remainder of the volumes of said shells and define a generally flat surface portion opposite to the curved sides of said shells, placing said bodies of plastic foam in said shells and bonding the concave surfaces of said shells to said bodies, bringing said two bodies together and bonding said flat surface portions together to define a generally toric life buoy, peripherally encircling said life buoy with a grab line, and attaching said grab line to said life buoy by placing metal cleats against the periphery of said life buoy and inserting screws through said cleats and said shells into said chocks.

References Cited in the file of this patent UNITED STATES PATENTS 1,201,556 Chlumsky Oct. 17, 1916 2,344,652 Spanner Mar. 21, 1944 2,482,074 Stephens Sept. 13, 1949 2,794,756 Leverenz June 4, 1957 FOREIGN PATENTS 15,303 Great Britain 1908 455,135 Great Britain Oct. 14, 1936 153,922 Sweden Mar. 27, 1956

Claims

2. A GENERALLY RIGID LIFE BUOY WHICH IS IMPERMEABLE TO WATER AND HAS HIGH RATIOS OF ITS STRENGTH AND ITS BUOYANCY TO ITS WEIGHT WHICH COMPRISES A PAIR OF COMPLEMENTARY SHELLS OF GENERALLY FRUSTO-TORIC SHAPE FORMED OF A RIGID WATER IMPERMEABLE PLASTIC, A BODY OF GENERALLY RIGID AND SUBSTANTIALLY IMPERMEABLE PLASTIC KFOAM MOUNTED IN EACH OF SAID SHELLS AND HAVING A GENERALLY CONVEX SURFACE BONDED TO THE CONCAVE SURFACE OF SAID SHELL AND A GENERALLY FLAT SURFACE PORTION LYING ALONG THE FLAT SIDE OF SAID SHELL, AND A LAYER OF GENERALLY RIGID PLASTIC BONDED ON OPPOSITE SIDES THEREOF TO SAID GENERALLY FLAT SURFACES OF SAID BODIES AND SECURING SAID BODIES AND SHELLS TOGETHER IN A GENERALLY TORIC SHAPE.