U.S. patent number 3,848,284 [Application Number 05/415,567] was granted by the patent office on 1974-11-19 for stringer system for glass fiber-reinforced boat hulls.
This patent grant is currently assigned to Reinell Boats, Inc.. Invention is credited to David T. Livingston.
United States Patent |
3,848,284 |
Livingston |
November 19, 1974 |
STRINGER SYSTEM FOR GLASS FIBER-REINFORCED BOAT HULLS
Abstract
Boat hulls of glass fiber-reinforced resin construction are
provided with a custom-molded, rigid, synthetic foam stringer
member providing an index to locate floor and interior components,
support floor, enclose fuel tank, incorporate bilge drains, provide
storage space, and stiffening for the hull and transom. The
stringer member, adapted to fit the inner contour of the boat hull,
is positioned in place in the hull and secured therein by
application of a layer or layers of glass fiber-reinforced resin
over the stringer member and adjacent portions of the hull. A floor
member is secured to the upper surface of the stringer member and a
subsequent layer or layers of glass fiber-reinforced resin applied
over the floor member and joints between the floor member and the
hull giving a continuous, uninterrupted surface. Additional
floation may be provided by injecting an expanding foam into one or
more of the hollow spaces defined by the boat hull, floor member
and stringer members. Motor mounts may be made an integral part of
the stringer member where desired.
Inventors: |
Livingston; David T. (Seattle,
WA) |
Assignee: |
Reinell Boats, Inc.
(Marysville, WA)
|
Family
ID: |
23646227 |
Appl.
No.: |
05/415,567 |
Filed: |
November 14, 1973 |
Current U.S.
Class: |
114/357 |
Current CPC
Class: |
B63B
5/24 (20130101) |
Current International
Class: |
B63B
5/00 (20060101); B63B 5/24 (20060101); B63b
005/00 () |
Field of
Search: |
;9/6,6.5 ;114/.5F |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Blix; Trygve M.
Assistant Examiner: Goldstein; Stuart M.
Attorney, Agent or Firm: Seed, Berry, Vernon &
Baynham
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A custom-molded stringer member for positioning in the interior
of a glass fiber-reinforced resin hull of a boat to provide
stiffening for the hull of the boat and support for the floor and
transom of the boat, comprising:
a stringer member including (1) one or more molded, rigid,
synthetic foam beams extending essentially parallel to the length
of hull of the boat having an essentially planar upper surface and
a lower surface adapted to fit the contour of the hull of the boat
and (2) one or more rigid cross braces extending between the beams,
each having a planar upper surface and a lower surface adapted to
fit the contour of the hull of the boat,
one or more layers of glass fiber-reinforced resin over the
stringer member and intersection of the stringer member with the
hull of the boat for securing the stringer member to the boat hull
and making it an integral part thereof,
a floor member adhered to the upper surface of the stringer member,
and
one or more layers of glass fiber-reinforced resin laid over the
floor member and intersection between the floor member and boat
hull.
2. The stringer system of claim 1 including one or more layers of
glass fiber-reinforced resin between the boat hull and the lower
surface of the stringer member for bonding the stringer member to
the boat hull at points of contact thereof.
3. The stringer member of claim 1 wherein the upper surface of the
beams and cross braces includes a molded in situ exposed wood
member providing stiffening to the stringer member and means of
adhering the floor member thereto.
4. The stringer member of claim 1 including molded-in-place bilge
drain tubes extending the width of the beams and cross braces for
draining water from the interior of the hull.
5. The stringer system of claim 1 wherein the rear portion of each
of the parallel beams of the stringer includes molded-in-situ
structural motor mounts.
6. A glass fiber-reinforced resin boat comprising:
a molded, glass fiber-reinforced resin hull,
a custom-molded stringer member of rigid, synthetic foam secured in
the boat hull providing stiffening for the hull and support for the
floor and transom of the boat, the stringer member including (1)
molded, rigid, synthetic foam beams extending essentially parallel
to the the length dimension of the hull of the boat having a planar
upper surface and a lower surface adapted to fit the contour of the
interior of the hull of the boat and (2) integral, molded, rigid
foam cross braces extending between the beams connecting the beams
together,
one or more layers of glass fiber-reinforced resin applied over the
beam and cross braces and the intersection between the beams, cross
braces and the hull for securing the stringer member to the hull to
form an integral part thereof, and
a floor member secured to the stringer member and supported
thereby.
7. The boat of claim 6 including one or more layers of glass
fiber-reinforced resin over the floor member for sealing the
intersection between the floor member and the hull and providing a
continuous, uninterrupted upper surface.
8. The boat of claim 7 wherein one or more of the hollow spaces
defined by the floor member, hull, cross braces and beams of the
stringer member is filled with an expanding synthetic foam
providing additional flotation for the boat.
9. A method of providing support for the floor in a boat and
stiffening for the hull and transom of a boat of glass
fiber-reinforced resin construction comprising:
providing a boat hull of glass fiber-reinforced resin
construction,
providing a custom-molded stringer member of rigid, molded
synthetic foam having molded, rigid, synthetic foam beams extending
essentially parallel to the length dimension of the hull of the
boat having a planar upper surface and a lower surface adapted to
fit the contour of the inner hull of the boat connected by
integral, molded, foam cross braces,
positioning the one-piece stringer member in place in the hull of
the boat,
securing the stringer member in place in the hull by application of
one or more layers of glass fiber-reinforced resin over the
stringer member and its intersection with the hull of the boat,
securing a floor member to the upper surface of the stringer
member, and
sealing the joints between the hull and the floor member.
10. The method of claim 9 wherein sealing includes applying one or
more layers of glass fiber-reinforced resin over the entire floor
member and its intersection with the hull of the boat to provide a
continuous, uninterrupted surface.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a system for providing floor support and
stiffening for boat hulls of glass fiber-reinforced resin
construction, to boats incorporating such a system and to the
method of installing the stringer system in a boat hull.
2. Prior Art Relating to the Disclosure
Boat hulls of glass fiber-reinforced resin construction are in
common use today. A conventional method used by boat manufacturers
for both stiffening the molded hull of the boat and providing
support for the floor of the boat has been to individually
construct structural framing of wood or plywood for each individual
hull, using jigs where possible. Such a procedure is time
consuming, wasteful of raw material and expensive because of the
labor cost and materials involved.
SUMMARY OF THE INVENTION
This invention is directed to a stringer system providing support
for a floor of a boat and stiffening for the hull and transom of
the boat. The system eliminates the structural framing
conventionally used, reduces the time of installation and reduces
labor costs significantly.
It is an object of this invention to provide a custom-molded
stringer member of rigid synthetic foam useful in conjunction with
a molded, glass fiber-reinforced resin hull of a boat.
It is a further object of this invention to provide custom-molded
stringer member of rigid foam for stiffening the molded hull of a
glass fiber-reinforced resin construction and providing support for
the floor of the boat.
It is a further object of this invention to provide a method of
stiffening the hull of a boat and of providing structural support
for the floor of the boat by utilizing a custom-molded rigid foam
stringer member.
The stringer member includes molded, rigid, synthetic beam members
extending essentially parallel to the hull of the boat having an
essentially planar upper surface and a lower surface adapted to fit
the contour of the interior of the hull of the boat, the parallel
beams connected by cross braces of integrally molded foam or other
suitable material. The stringer member is positioned in the boat
and secured therein with a layer or layers of glass
fiber-reinforced resin applied over the beams and cross braces of
the stringer and the intersection between the hull and the stringer
member to secure the stringer member in place. A floor member is
then adhered to the upper surface of the stringer member and an
additional layer or layers of glass fiber-reinforced resin applied
over the entire surface of the floor member and the seam between
the floor member and the boat hull to provide a continuous,
uninterrupted surface. The stringer member serves (1) as an index
to locate the floor and interior components of the boat, (2)
support the floor, (3) enclose fuel tank, (4) incorporate bilge
drains, (5) provide storage space, ( 6) provide additional
flotation and (7) provide stiffening for the hull and transom.
Additional flotation is added to the boat by injecting an expanding
foam into the hollow chambers defined by the boat hull, the
parallel beams and cross braces of the stringer member and the
floor member. Integral motor mounts may be provided as a part of
the stringer member near the rear of the boat for mounting of a
motor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a molded boat hull of glass
fiber-reinforced resin construction illustrating the stringer
member in position in the boat hull;
FIG. 2 is a vertical cross-section along line 2--2 of FIG. 1;
FIG. 3 is a vertical cross-sectional view along section line 3--3
of FIG. 2;
FIG. 4 is a perspective view of the stringer member illustrating
the top side thereof;
FIG. 5 is a perspective view of the stringer member of FIG. 4
illustrating the underside thereof; and
FIG. 6 is a perspective view of a stringer member modified to
include a motor mount for an inboard engine.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 - illustrate a molded boat hull 10 of conventional glass
fiber-reinforced resin construction with the stringer system
installed therein. The system described herein is useful with any
configuration of boat hull, although it will be described for
purposes of the application with respect to the boat hull
illustrated. To provide stiffening for the boat hull and support
for the floor member and transom of the boat, a custom-made,
stringer member 20 of rigid, expanded foam construction is
positioned in the hull of the boat and secured therein. The
stringer member 20 is illustrated by FIGS. 4 and 5. The stringer
member consists of two parallel beams of expanded foam 21 connected
at spaced intervals by integral cross braces 22, which may be of
expanded foam or other suitable material. The parallel beams and
cross braces have an essentially planar upper surface for receiving
the floor member for the boat. The lower surface of the beams and
cross braces is contoured to fit the particular boat hull in which
the stringer member is to be used. Wood strips 23 are molded in the
upper surface of the beams and cross braces as illustrated by FIG.
4 to provide stiffening for the stringer member as well as to
provide means for attachment of the floor member to the stringer
member by staples, nails, adhesive or other suitable means.
The lower or undersurface of the parallel beams includes
projections 24 which are designed to index with the strakes 11 of
the molded hull as illustrated by FIG. 3. Plastic bilge drain tubes
25 are molded in place at the rear of the beams and in each one of
the cross braces as illustrated to provide drainage to the rear of
the boat hull in the event of any leakage. Molded-in-place ledges
may be provided to support the motor as illustrated in FIG. 4 for
using an inboard-outboard engine.
The stringer member is made by initially fabricating a mold of the
stringer member so that the stringer produced will fit the contour
and design of the particular boat hull in which it is to be
utilized. Once the mold is made, the interior thereof is coated
with a suitable release agent and strips of plywood or other
suitable material are laid in the portion of the mold corresponding
to the upper surface of the stringer member. Plastic bilge drain
pipes 25 are inserted in the mold where necessary and an expanding
foam, such as a polyurethane foam, is injected into the mold to
fill it. After a suitable curing time, the mold is opened and the
stringer member removed. The particular foaming resin does not form
a part of this invention -- any suitable resin system may be used.
A preferred resin system is a polyurethane foam made by mixing a
resin component with a catalyst and blowing agent and injecting the
mixed foaming resin immediately into the mold wherein the foam
expands to fill the mold. The curing time of the resin generally
ranges from 30 to 60 minutes.
Once the stringer member has been made, it is positioned in place
in the hull of the boat and secured therein. The member may be
secured to the hull by first applying a layer 26 of glass
fiber-reinforced resin over those areas of the hull where the beams
and cross braces of the stringer member will rest and, while the
resin is still uncured, positioning the stringer member in place.
After the stringer member is positioned in place, one or more
layers of glass fiber-reinforced resin are applied over the beams
and cross braces of the stringer member and the seams between the
stringer member and the boat hull to effectively bond the stringer
member in place in the hull. If desired, a combination of chopped
glass and woven glass, woven glass alone, or chopped glass alone
admixed with resin may be employed, depending on the desires of the
building and the boat design.
A floor member 27 of plywood or other suitable material cut to fit
the boat hull is laid over the stringer member and secured thereto
by inserting staples, nails or other suitable fastening elements
through the floor member into the strips of wood 23, which form an
integral part of the beams and cross braces of the stringer member.
Prior to positioning the floor member in place, a bead 28 of glass
fiber-reinforced resin may be run along the portion of the hull
contacting the floor member (FIG. 3) to effectively bond the floor
member to the hull. After the floor member is secured in place, one
or more layers 29 of glass fiber-reinforced resin may be applied
over the entire floor and the seams between the floor and the hull
of the boat or applied only at the seams between the hull and the
floor member.
If the stringer system described is to be used with a boat hull for
mounting of an inboard motor, integral motor supports 30 can be
formed in the rear portions of the parallel beams as illustrated by
FIG. 6.
Prior to application of the layer or layers 29 of glass
fiber-reinforced resin over the floor, additional flotation may be
added to the boat by cutting one or more openings in the floor
member and injecting an expanding foam into one or more of the
hollow chambers 30 and 31 formed by the boat hull, beams and cross
braces of the stringer member, and floor member. The expanding foam
fills the hollow chamber or chambers and provides additional
flotation capacity for the boat hull.
One of the hollow chambers, such as the middle chamber 31, may be
used to hold a gasoline tank or be used for storage space.
The stringer system described eliminates the necessity of
individually building structural framing for each boat hull and
provides stiffening for the hull and support for the floor member
and transom of the boat. Once a particular boat hull is designed, a
mold is made for the stringer system to fit that particular boat
hull and the stringer members fabricated quickly and at much less
cost than necessary with individual framing systems for each boat
hull. All of the sequential steps for securing the stringer to the
hull can be accomplished without prior curing of the previous step,
thus reducing the overall installation time.
* * * * *