Boat and method for manufacturing

Information

  • Patent Grant
  • 6286448
  • Patent Number
    6,286,448
  • Date Filed
    Wednesday, September 15, 1999
    25 years ago
  • Date Issued
    Tuesday, September 11, 2001
    23 years ago
Abstract
The present disclosure relates to a boat including a hull having an interior region. The boat also includes an insert mounted within the hull. The insert includes a bottom piece having a bottom side that complements and nests within the interior region of the hull. The insert also includes a top piece secured to the bottom piece. The top and bottom pieces cooperate to define an inner foam chamber. The insert further includes a volume of foam positioned within the foam chamber.
Description




FIELD OF THE INVENTION




The present invention relates generally to boats. More particularly, the present invention relates to boats having fiberglass hulls and to methods for manufacturing such boats.




BACKGROUND OF THE INVENTION




Boat hulls have historically been made of many different types of material such as aluminum, steel or wood. Another common material used in the manufacture of boat hulls is a laminate material made of fiberglass-reinforced resin.




Open face molds are frequently used to manufacture fiberglass hulls. To make a hull with an open face mold, a layer of gel coat is frequently first applied to the mold. Next, a barrier layer is often applied to the gel coat. Finally a layer of fiberglass-reinforced resin is applied to the barrier layer. When the hull is removed from the mold, the gel coat provides a smooth, aesthetically pleasing outer surface of the hull. The barrier layer prevents the fiberglass from printing or pressing through the gel coat. The fiberglass provides the hull with structural rigidity.




With fiberglass boats, it is often desirable to inject foam into foam compartments formed within the boats. The injection of foam presents several problems. For example, when foam is injected into a boat, pressure generated by the foam injection process can cause portions of the boat to bow or buckle outward thereby negatively affecting the appearance and structural integrity of the boat. This can be particularly problematic with respect to unsupported parts manufactured by injection molding or resin transfer molding operations. Also, to access foam chambers within a boat, it is often necessary to drill holes through portions of the boat. This is problematic because the drilling of holes can cause the aesthetically pleasing outer gel coat surface to be damaged. The repair of such damage can be time consuming.




SUMMARY OF THE INVENTION




One aspect of the present invention relates to a boat including a hull having an interior region. The boat also includes an insert mounted within the hull. The insert includes a bottom piece having a bottom side that complements and nests within the interior region of the hull. The insert also includes a top piece secured to the bottom piece. The top and bottom pieces cooperate to define an inner foam chamber. The insert further includes a volume of foam positioned within the foam chamber.




Another aspect of the present invention relates to a method for manufacturing a boat. The method includes providing a hull. The method also includes providing an insert having a top piece and a bottom piece that cooperate to define a foam chamber. The method further includes injecting foam into the foam chamber of the insert, and securing the insert within the hull.




A further aspect of the present invention relates to a method for making a boat including providing a boat structure including a hull and a deck, supporting the boat structure between at least two mold pieces, and injecting foam into a foam chamber defined within the boat structure. The foam is injected in the foam chamber while the boat structure is concurrently supported by the at least two mold pieces.




A variety of advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practicing the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.











BRIEF DESCRIPTION OF THE DRAWINGS




The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several aspects of the invention and together with the description, serve to explain the principles of the invention. A brief description of the drawings is as follows:





FIG. 1

is a perspective view of a boat constructed in accordance with the principles of the present invention;





FIG. 2

is an exploded, perspective view of the boat of

FIG. 1

;





FIG. 3

is a cross-sectional view taken along section line


3





3


of

FIG. 1

;





FIG. 4

is a cross-sectional view of an insert used in the boat of

FIG. 1

, the insert is shown supported between top and bottom molds;





FIG. 5

is a plan view illustrating an adhesive pattern used in the hull of the boat of FIG.


1


;and





FIG. 6

is a cross-sectional view of an alternative boat in the process of having foam injected within a foam chamber of the boat.











DETAILED DESCRIPTION




Reference will now be made in detail to exemplary aspects of the present invention that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.





FIG. 1

is a perspective view of a boat


20


constructed in accordance with the principles of the present invention. The boat


20


includes a hull


22


(shown in phantom line) including a bow


24


positioned opposite from a stern


26


. A keel


28


extends between the bow


24


and the stern


26


. Chines


30


and strakes


27


(best shown in

FIG. 3

) are located on port and starboard sides of the hull


22


. The boat


20


also includes a pan or insert


32


mounted within the hull


22


. The insert


32


provides structural rigidity or reinforcement to the hull


22


. As shown in

FIG. 2

, the insert


32


is formed by a top piece


36


and a bottom piece


38


.




The top piece


36


of the insert


32


includes a generally planar, horizontal top surface that forms an upper deck or platform


34


of the boat


22


. The top piece


36


also includes first and second supports


41


and


42


. The supports


41


and


42


extend widthwise across the top piece


36


and are configured for providing structural reinforcement to the hull


22


. The top piece


36


further includes an upper lip or flange


50


. The flange


50


projects transversely outward from the top edge of the top piece


36


, and extends generally about a perimeter of the top piece


36


.




Still referring to

FIG. 2

, the top piece


36


also defines a plurality of internal compartments. For example, the top piece


36


defines a front storage compartment


44


positioned in front of the second support


42


, a middle fuel-tank compartment


46


positioned between the first and second supports


41


and


42


, and a rear engine compartment


48


positioned behind the first support


41


. The front and middle compartments


44


and


46


preferably can be covered with removable panels (not shown).




Referring again to

FIG. 2

, the bottom piece


38


of the insert


32


includes an interior region


52


sized for receiving the top piece


36


. The interior region


52


is configured to generally complement a bottom profile of the top piece


36


such that the top piece


36


can nest within the interior region


52


.

FIG. 3

shows the top piece


36


nested within the bottom piece


38


. As so nested, keel regions


53


of the top and bottom pieces


36


and


38


engage one another in a parallel relationship. Additionally, chine regions


55


of the top and bottom pieces


36


and


38


engage one another in a parallel relationship. In the keel and chine


53


and


55


regions, no substantial gap exists between the top and bottom pieces


36


and


38


. By contrast, between the keel and chine regions


53


and


55


, the top and bottom pieces


36


and


38


separate from one another so as to define foam chambers


54


having generally triangular cross-sections. As shown in

FIG. 3

, each foam chamber


54


is defined by an upright wall


56


of the top piece


36


, a horizontal wall


58


of the top piece


36


, and an inclined wall


60


of the bottom piece


38


. Each foam chamber


54


is filled with a volume of foam


73


.




A bottom side or bottom profile of the bottom piece


38


is configured to complement and nest within an interior region


62


(best shown in

FIG. 2

) of the hull


22


. When nested within the hull


22


as shown in

FIG. 3

, substantially the entire bottom surface of the bottom piece


38


makes generally parallel contact with the interior region


62


of the hull


22


. Also, a top flange


64


that extends about the perimeter of the bottom piece


38


seats upon a shoulder


66


defined by the interior region


62


of the hull


22


. Further, a plurality of strake projections


68


formed on the bottom of the bottom piece


38


fit within complementary strake recesses


70


formed along the interior region


62


of the hull


22


.




It is preferred for the top piece


36


to be manufactured by an open face molding process. To practice such a process, a layer of gel coat (e.g., about 0.020-0.024 inches thick) is first applied to an open face mold. Next, a layer of reinforcing chop material and resin (e.g., about 0.090-0.100 inches thick) is applied over the gel coat. For example, fiberglass can be applied by blowing a mixture of resin and fiberglass chop strand onto the gel coat layer to form a wet laminate layer. The wet laminate layer is then rolled out, and reinforcements can be laid within the wet laminate material. Exemplary types of reinforcements include aluminum plates/members for mounting seats, coremat for preventing the seat mounts from printing through the fiberglass laminate, and wood reinforcements for providing a motor mount and for providing a tank cover and storage lid hold-down function. Upon curing, the laminate preferably has a thickness of about 0.100 inches and forms a generally rigid shell containing the reinforcements.




While it is preferred to use an open face molding process, it will be appreciated that the top piece


36


can be manufactured by any number of known techniques. For example, the top piece


36


can be manufactured by a resin transfer molding process, an injection molding process, or any other known technique. U.S. application Ser. No. 08/715,533 filed on Sep. 18, 1996 and entitled Apparatus For Molding Composite Articles, which is hereby incorporated by reference, discloses an exemplary resin transfer molding process. It will also be appreciated that the hull


22


and the bottom piece


38


can be manufactured by techniques similar to those described with respect to the top piece


36


. For example, in one particular embodiment, the bottom piece


38


can be manufactured by an open face molding process in which a fiberglass laminate is applied to an open face mold. In such an embodiment, no gel coat layer, barrier layer or reinforcements are used, and the bottom piece


38


can have a laminate thickness of about 0.06 inches.




In one particular non-limiting embodiment of the hull


22


, the hull has an outer gel coat layer of about 0.024 inches, and intermediate barrier layer of about 0.035 inches, and an inner fiberglass layer of about 0.25-0.375 inches. The barrier layer prevents the fiberglass from pressing through the gel coat.




To assemble the insert


32


, a layer of adhesive (e.g., a polyester putty) is preferably spread either along the bottom surface of the flange


50


, or along the top surface of the flange


64


. At the time the adhesive is applied, the top piece


36


is preferably supported by a first open face mold


72


(shown in

FIG. 4

) and the bottom piece


38


is supported by a second open face mold


74


(shown in FIG.


4


). While supported by their corresponding open faced molds


72


and


74


, the top piece


36


is placed or nested within the interior region


52


of the bottom piece


38


. As so positioned, the first and second open faced molds


72


and


74


are clamped together thereby compressing the adhesive between the flanges


50


and


64


.




With the two open face molds


72


and


74


clamped together, foam


73


(e.g., a polyurethane loam that becomes generally rigid upon curing) is preferably injected into the foam chambers


54


. Preferably, the foam


73


is injected through


10


to


12


holes that have been pre-drilled through either the bottom piece


38


or the top piece


36


. During the injection process, the open face molds


72


and


74


prevent the top and bottom pieces


36


and


38


from bowing or buckling away from one another. Consequently, the molds


72


and


74


assist in improving the aesthetic appearance and design tolerance of the insert


32


.




Referring to

FIG. 4

, the pre-drilled holes have been located in two different locations. For example, a first set of pre-drilled holes


76


have been drilled through the inclined walls


60


of the bottom piece


38


. The first set of holes


76


are in fluid communication with the foam chambers


54


. Nozzles or conduits


78


that extend through the second open face mold


74


are used to inject the foam into the foam chambers


54


through the first set of openings


76


.




A second set of openings


80


have been pre-drilled through the upright walls


56


of the top piece


36


. Similar to the openings


76


, the openings


80


are in fluid communication with the foam chambers


54


. Nozzles or conduits


82


that extend through the first open face mold


72


are used to inject foam into the foam chambers


54


through the second set of openings


80


.




The locations of the first and second sets


76


and


80


of openings are advantageous because such openings are located at inconspicuous positions. Consequently, it is not necessary to refinish these regions after the injection molding process. By contrast, the horizontal, top wall


58


of the top piece


36


forms the platform


34


of the boat


22


. Holes through this region would be highly visible and would damage the outer gel coat finish. Consequently, holes through the horizontal, top wall


58


would most likely necessitate refinishing of the top surface


40


of the top piece


36


.




After the foam


73


has cured within the foam chambers


54


, the insert


32


is removed from the open face molds


72


and


74


, and is inserted into the interior region


62


of the hull


22


. An adhesive material (e.g., an adhesive sold by Applied Products, Inc. under the name Plexus) is preferably used to secure the insert


32


within the hull


22


. A solvent can be used to prepare or clean the surface of the hull prior to applying the adhesive.




As shown in

FIG. 5

, a plurality of beads


84


of adhesive are applied to the interior region


62


of the hull


22


prior to inserting the insert


32


therein. When the insert


32


is inserted within the hull


22


, an adhesive bond is formed between the hull


22


and the bottom surface of the bottom piece


38


.




The beads


84


of adhesive are preferably arranged in a pattern for allowing water to drain between the hull


22


and the bottom piece


38


. Each bead


84


is generally U-shaped and includes two legs


86


that are generally perpendicular with respect to the keel


28


. Rounded ends


88


of the beads


84


are located adjacent the port and starboard sides of the hull


22


. Open ends


90


of the beads


84


are located adjacent to the keel


28


of the hull


22


. The legs


86


of the beads are aligned generally parallel to one another. Flow passageways


92


are defined between each of the beads


84


. The flow passageways


92


allow water to drain along the interior region


62


of the hull


22


from the chines


30


toward the keel


22


. A drainage opening (not shown) is preferably located at the keel


28


adjacent to the stern


26


for allowing water to drain from the hull


22


. The particular configuration of the adhesive beads


84


is advantageous because it prevents water from being captured or otherwise retained between the insert


32


and the hull


22


. Retained water is problematic because at cold temperatures the water can freeze and cause cracking of the hull


22


.




In addition to the U-shaped beads


84


of adhesive, a layer of adhesive can also be applied about the shoulder


66


of the hull


22


. This adhesive extends about the perimeter of the bottom piece


38


of the insert


32


, and forms a sealed bond between the bottom side of the flange


64


and the top side of the shoulder


66


.





FIG. 6

is a cross sectional view of an alternative boat


20


′ constructed in accordance with the principles of the present invention. The boat


20


′ is in the process of being injected with foam. Parts similar to those previously described with respect to the embodiment of

FIGS. 1-5

will be assigned like numbers with the addition of apostrophes to distinguish the embodiments.




The boat


20


′ has a similar configuration as the boat


20


, except the bottom piece


38


of the insert


32


has been eliminated. Instead, a one-piece insert


36


′ is mounted within a hull


22


′ of the boat


20


′. Foam chambers


54


′ are defined between the insert


36


′ and the hull


22


′.




As shown in

FIG. 6

, the insert


36


′ is supported within a first open mold


72


′ and the hull


22


′ is supported in a second open mold


74


′. The open molds


72


′ and


74


′ are clamped together such that the boat


20


′ is contained between the molds


72


′ and


74


′.




A set of openings


80


′ have been pre-drilled through upright walls


56


′ of the insert piece


36


′. The openings


80


′ are in fluid communication with the foam chambers


54


′. Nozzles or conduits


82


′ that extend through the first open face mold


72


′ are used to inject foam into the foam chambers


54


′ through the second set of openings


80


′.




With regard to the foregoing description, it is to be understood that changes may be made in detail, especially in matters of the construction materials employed and the shape, size and arrangement of the parts without departing from the scope of the present invention. It is intended that the specification and depicted aspects be considered exemplary only, with a true scope and spirit of the invention being indicated by the broad meaning of the following claims.



Claims
  • 1. A boat comprising:a) a hull having an interior region, keel and chines; and b) an insert mounted within the hull, the insert including: i) a bottom piece including a bottom side that complements and nests within the interior region of the hull, wherein the bottom piece of the insert is affixed to the hull by adhesive, the adhesive being arranged in a pattern configured for allowing water to drain along the interior region of the hull from the chines to the keel and wherein the pattern includes a plurality of beads having portions that are parallel to one another and transverse with respect to the keel; ii) a top piece secured to the bottom piece, the top and bottom pieces cooperating to define an inner foam chamber; and iii) a volume of foam positioned within the foam chamber.
  • 2. The boat of claim 1, wherein the bottom side of the bottom piece defines a plurality of openings for allowing the foam to be injected into the foam chamber.
  • 3. The boat of claim 1, wherein the top piece includes an upright wall defining a plurality of openings for allowing the foam to be injected into the foam chamber.
  • 4. The boat of claim 1, wherein the bottom side of the bottom piece includes strakes that fit within complementary strake recesses that extend along the interior region of the hull.
  • 5. A method for manufacturing a boat comprising:providing a hull, the hull comprising a bow region and a stern region; providing an insert sized to extend from the bow region to the stern region and having a top piece and a bottom piece, wherein the top and bottom pieces include keel regions that engage one another in a parallel relationship and chine regions that engage one another in parallel relationship, the top and bottom pieces separating from one another between the chine and keel regions to define foam chambers; injecting foam into the foam chambers of the insert; and securing the insert within the hull.
  • 6. The method of claim 5, wherein the insert is secured within the hull after the foam chamber has been filled with foam.
  • 7. The method of claim 5, wherein the foam is injected through a hole defined by the bottom piece.
  • 8. The method of claim 5, wherein the bottom piece mates with the hull.
  • 9. The method of claim 5, wherein the top piece includes a top surface and an upright wall aligned generally transversely with respect to the top surface, and wherein the foam is injected through a hole defined by the upright wall of the top piece.
  • 10. The method of claim 5, wherein the foam is injected into the foam chamber while the insert is enclosed and supported between two mold pieces.
  • 11. The method of claim 10, wherein the mold pieces include passageways for directing the foam through the molds and into the foam chamber of the insert.
  • 12. The method of claim 5, wherein a bottom side of the bottom piece includes strakes that fit within complementary strake recesses that extend along an interior region of the hull.
  • 13. The method of claim 5, wherein the top piece includes a top wall that forms an upper platform of the boat.
  • 14. The method of claim 5, wherein the insert piece includes a top outwardly projecting lip that extends about a majority of a perimeter of the insert piece and seats on a corresponding shoulder defined by an interior region of the hull.
  • 15. A method for making a boat comprising:providing a boat structure including a hull and a deck, wherein the deck is formed by an insert piece including a top surface and an upright wall aligned transversely with respect to the top surface; supporting the boat structure between at least two mold pieces; and injecting foam into a foam chamber defined within the boat structure through a hole defined by the upright wall while the boat structure is concurrently supported by the at least two mold pieces.
  • 16. The method of claim 15, wherein the foam is injected through at least one of the at least two mold pieces.
US Referenced Citations (13)
Number Name Date Kind
2909791 Malary, Jr. Oct 1959
3840926 Stoeberl Oct 1974
3848284 Livingston Nov 1974
4214332 Stoner Jul 1980
4719871 Fantacci et al. Jan 1988
4778420 Greenberg Oct 1988
5035602 Johnson Jul 1991
5036790 Berryer Aug 1991
5045251 Johnson Sep 1991
5063870 Wagner Nov 1991
5069414 Smith Dec 1991
5458844 MacDougall Oct 1995
5875731 Abernethy et al. Mar 1999