Information
-
Patent Grant
-
6314904
-
Patent Number
6,314,904
-
Date Filed
Wednesday, October 11, 200023 years ago
-
Date Issued
Tuesday, November 13, 200122 years ago
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Inventors
-
-
Examiners
Agents
- Weins; Michael J.
- Semprebon; Jeffrey E.
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
A collapsible canoe has a frame which includes a pair of gunwales connected together at each end by a gunwale terminator, a thwart separating the gunwales, a series of ribs connected to the gunwales, a keel stringer and supplemental bottom stringers traversing the ribs, and a pair of stem elements attached to the keel stringer. The collapsible canoe also has a skin covering the frame which has two gunwale sleeves which engage the gunwales, side panels attached to the gunwale sleeves, a bottom panel attached to the side panels, and a pair of terminator panels connecting the side panels to each other and to the bottom panel. The skin may be tensioned by inflatable compartments between the frame and the skin. The skin may alternatively be tensioned by the ribs. In one embodiment, a prong attached to each stem element engages a slot in each terminator panel to stabilize the stem elements with respect to the gunwale terminators. In another embodiment, a strap attached to each terminator panel is adjustably engaged with an anchor member which is affixed to each stem element to stabilize the stem elements with respect to the gunwale terminators.
Description
FIELD OF THE INVENTION
The present invention relates to a collapsible canoe which facilitates assembly without compromising the integrity of the assembled canoe.
BACKGROUND OF THE INVENTION
Collapsible canoes have been available for many years. One early canoe which was well suited for packing is described in U.S. Pat. No. 4,290,157. More recently, collapsible canoes which offer improvements on the design of the '157 canoe have been developed and marketed by ScanSport, Inc. Another collapsible canoe is described in U.S. Pat. Nos. 5,615,634 and 5,964,178.
FIGS. 1 through 4
illustrate a prior art collapsible canoe
10
which represents an earlier design marketed by ScanSport, Inc. The collapsible canoe
10
has a frame
12
which includes a pair of gunwales
14
, each having a bow end
16
and a stern end
17
. A pair of gunwale terminators
18
connect the bow ends
16
of each of the gunwales
14
together and connect together the stem ends
17
of each of the gunwales
14
.
The frame
12
also includes a series of ribs
20
, each attached to the gunwales
14
with gunwale-engaging clips
22
, one of which is shown in detail in FIG.
2
. At least one thwart
24
is connected to the gunwales
14
to maintain a separation therebetween. In the collapsible canoe
10
illustrated, the thwart
24
is attached to the rib
20
′, and is connected to the gunwales
14
thereby.
The frame
12
has a keel stringer
26
, which traverses the ribs
20
. The frame
12
also has supplemental bottom stringers
28
which traverse the ribs
20
and are symmetrically disposed with respect to the keel stringer
26
. The keel stringer
26
and supplemental bottom stringers
28
are engaged by stringer-engaging clips
30
on the ribs
20
, and define a bottom region of the frame
12
. The stringer-engaging clips
30
limit lateral motion of the keel stringer
26
and the supplemental bottom stringers
28
along the ribs
20
, while allowing longitudinal motion normal to the ribs
20
.
A pair of stem elements
32
(only one of which is visible) are slidably engaged with and terminate the keel stringer
26
. Each of the stem elements
32
extends up to one of the gunwale terminators
18
. The supplemental bottom stringers
28
terminate at bottom stringer terminators
34
(as better shown in
FIG. 3
) which are affixed to the stem elements
32
. In combination, the stringer-engaging clips
30
and bottom stringer terminators
34
maintain the supplemental bottom stringers
28
in position.
The collapsible canoe
10
has a skin
36
which covers the frame
12
. In the view of
FIG. 1
, the skin
36
is shown partially cut away to better show the structure of the collapsible canoe
10
. The frame
12
supports the skin
36
, and also is supported thereby, since the elements of the frame
12
are, for the most part, not secured to each other. Such cooperation between the frame
12
and the skin
36
reduces the number of connectors needed for assembly of the collapsible canoe
10
to simplify assembly and disassembly.
The skin
36
has a pair of gunwale sleeves
38
which engage the gunwales
14
of the frame
12
to secure the skin
36
to the frame
12
. Tension of the skin
36
secures the gunwales
14
to the gunwale-engaging clips
22
on the ribs
20
. The skin
36
also has a pair of side panels
40
which may be formed integrally with the gunwale sleeves
38
, but which are preferably constructed as separate elements to better accommodate the curvature of the frame
12
and to allow the use of a lighter weight fabric for the side panels
40
to minimize weight. A bottom panel
42
is attached to the side panels
40
. The side panels
40
are attached to the bottom panel
42
and to each other at two end seam regions
44
(only one of which is shown).
Means for tensioning the skin
36
are provided by a pair of inflatable compartments
46
which reside between the side panels
40
and the frame
12
when the collapsible canoe
10
is assembled. The inflatable compartments
46
, when inflated, help maintain the skin
36
tautly in place on the frame
12
. The inflatable compartments
46
are preferably removably attached to the skin
36
to facilitate replacement if damaged.
In the collapsible canoe
10
, each stem element
32
is provided with means for securing one of the gunwale terminators
18
to the stem element
32
. The means for securing one of the gunwale terminators
18
to the stem element
32
are provided by a gunwale terminator securing strap
47
in combination with a vertical stop
48
, as better shown in FIG.
4
. The gunwale terminator securing strap
47
is attached to the stem element
32
, passes over the stem element
32
and around the gunwale terminator
18
, and is secured to the vertical stop
48
with snaps
49
. The vertical stop
48
is in turn affixed to the stem element
32
. The gunwale terminator securing strap
47
binds the gunwale terminator
18
to the stem element
32
to secure it thereto, and the vertical stop
48
limits motion of the gunwale terminator
18
with respect to the stem element
32
as well as securing the gunwale terminator securing strap
47
.
While the gunwale terminator securing strap
47
and the vertical stop
48
provide means to secure the gunwale terminator
18
to the stem element
32
, it has been found that such securing means are not necessary. Upwards forces on the stem element
32
, which are discussed in greater detail below, in combination with tension in the skin
36
, serve to secure the stem element
32
with respect to the gunwale terminator
18
, making the securing of these elements together by employing additional frame elements unnecessary. Elimination of such additional frame elements simplifies fabrication and assembly/disassembly of the collapsible canoe
10
.
FIGS. 5 through 8
illustrate the bow end of another prior art collapsible canoe
50
which represents a more recent model marketed by ScanSport, Inc., and which offers several improvements over the collapsible canoe
10
discussed above. These improvements, which are discussed in greater detail below, may be summarized as follows. The collapsible canoe
50
eliminates the means to secure the gunwale terminator to the stem element and instead connects the gunwale terminator and stem element together using hardware which is identical to that which connects the ribs to the gunwales, which facilitates fabrication of the collapsible canoe
50
. The skin of the collapsible canoe
50
is provided with terminator panels at the ends, minimizing leakage of the skin. Finally, the collapsible canoe
50
is provided with inflatable compartment support rods which improve the appearance.
The overall layout of the collapsible canoe
50
is similar to that of the collapsible canoe
10
. The stern end of the collapsible canoe
50
(not shown) is similar to the bow end which is illustrated. The collapsible canoe
50
again has a frame
52
which includes a pair of gunwales
54
, each having a bow end
56
and a stern end (not shown). A gunwale terminator
58
connects the bow ends
56
of each of the gunwales
54
together.
The frame
52
also includes a series of ribs
60
, each of which is attached to the gunwales
54
with gunwale-engaging clips
62
. At least one thwart
64
is connected to the gunwales
54
to maintain a separation between the gunwales
54
. In the collapsible canoe
50
, the thwart
64
is attached to the rib
60
′, which in turn is attached to the gunwales
54
.
The frame
52
has a keel stringer
66
and supplemental bottom stringers
68
which traverse the ribs
60
and are engaged by stringer-engaging clips
70
on the ribs
60
. A stem element
72
terminates the keel stringer
66
, and extends up to the gunwale terminator
58
. The supplemental bottom stringers
68
terminate at bottom stringer terminators
74
which are affixed to the stem element
72
.
The collapsible canoe
50
has a skin
76
which covers and supports the frame
52
.
FIG. 7
is an exploded view of the skin
76
. The skin
76
has a pair of gunwale sleeves
78
which engage the gunwales
54
of the frame
52
, a pair of side panels
80
attached to the gunwale sleeves
78
, and a bottom panel
82
which is attached to the side panels
80
. Preferably, the bottom panel
82
is provided with a bottom foam lining
83
to minimize abrasion.
A terminator panel
84
attaches the side panels
80
to each other and to the bottom panel
82
. In the collapsible canoe
50
, the terminator panel
84
is formed by an extension of the bottom panel
82
, to which the side panels
80
are attached. It should be appreciated that the terminator panel
84
could be a separate element, such as a heat sealable tape applied over a seam connecting the side panels
80
and bottom panel
82
together.
Referring again to
FIGS. 5 and 6
, means for tensioning the skin
76
are again provided by a pair of inflatable compartments
86
which reside between the side panels
80
and the frame
52
when the collapsible canoe
50
is assembled. The inflatable compartments
86
, when inflated, help maintain the skin
76
tautly in place on the frame
52
. In the collapsible canoe
50
, an inflatable compartment support rod
88
is provided on either side of the collapsible canoe
50
to provide longitudinal support for the inflatable compartments
86
to improve the appearance of the collapsible canoe
50
.
In the collapsible canoe
50
, the stem element
72
is connected to the gunwale terminator
58
by the gunwale-engaging clip
62
′, which is shown in greater detail in FIG.
8
. The gunwale engaging clip
62
′ limits motion between the gunwale terminator
58
and the stem element
72
, but does not secure these elements to each other. As discussed above, securing the stem element
72
to the gunwale terminator
58
is not necessary, since tension of the skin
76
maintains the gunwale terminator
58
secured with the stem element
72
.
It has been found that both the collapsible canoe
10
and the collapsible canoe
50
suffer from stresses on the skin (
36
,
76
) which can cause damage to the gunwale sleeves (
38
,
78
). This problem is discussed with regard to the collapsible canoe
50
in reference to
FIGS. 5 through 8
.
When the collapsible canoe
50
is assembled, the gunwales
54
are inserted into the gunwale sleeves
78
, exiting at sleeve ends
90
, and are connected together by the gunwale terminator
58
. The keel stringer
66
, with the stem element
72
attached thereto, is placed in the skin
76
and the gunwale-engaging clip
62
′ is engaged with the gunwale terminator
58
. Each supplemental bottom stringer
68
is attached to one of the bottom stringer terminators
74
. The ribs
60
are then installed by engaging the gunwale engaging clips
62
of the rib
60
with the gunwales
54
, the gunwale-engaging clips
62
being secured in such engagement by the tension of the skin
76
. The supplemental bottom stringers
68
are then moved toward the keel stringer
66
and maintained in position by the stringer engaging clips
70
.
As the supplemental bottom stringers
68
are moved toward the keel stringer
66
, they exert force on the stem element
72
via the bottom stringer terminators
74
, forcing the stem element
72
into the terminator panel
84
of the skin
76
. As shown in
FIG. 6
, the angle of the stem element
72
is less than 90°. As the stem element
72
is forced into the terminator panel
84
with a longitudinal force F
1
, the angle of the stem element
72
causes a substantial upwards force F
2
.
A moderate amount of upwards force F
2
is desirable, since it maintains the gunwaleengaging clip
62
′ engaged with the gunwale terminator
58
. However, it has been found that the upwards force F
2
of the stem element
72
frequently causes stress on the gunwale sleeves
78
, since the upwards force F
2
is transferred to the gunwales
54
via the gunwale engaging clip
62
∝ and the gunwale terminator
58
. This stress on the gunwale sleeves
78
may be great enough to cause failure at the sleeve ends
90
when the collapsible canoe
50
is used in extreme conditions, such as in whitewater rapids and the like. Such failure of the gunwale sleeves
78
has even been found despite additional stitching and reinforcement of the sleeve ends
90
.
Again, while not shown, it should be noted that an identical situation exists at the stern end of the collapsible canoe
50
.
FIG. 9
is a perspective view of a collapsible canoe
100
such as described in U.S. Pat. Nos. 5,615,634 and 5,964,178, which represents a still more recent development. The collapsible canoe
100
differs from the collapsible canoes discussed above in that it employs a free-standing, isotropically secure frame
102
which is intended to provide structural integrity which is independent of the skin. The frame
102
includes a pair of gunwales
104
, each having a bow end
106
and a stem end
108
. A pair of gunwale terminators
110
connect the bow ends
106
and the stem ends
108
of each of the gunwales
104
together.
As part of the securing system to provide a free-standing, isotropically secure frame
102
, a pair of stem elements
112
are each attached to a keel stringer
114
and extend up to a stem end
116
which is provided with means for securing one of the gunwale terminators
110
to the stem end
116
. The means for securing one of the gunwale terminators
110
to the stem end
116
are provided by a gunwale fastener
118
and securing strap
120
, which are better shown in the detail view of FIG.
10
.
The frame
102
also includes a series of ribs
122
, each of which is secured to the gunwales
104
by rib-gunwale lockconnectors
124
, one of which is shown in detail in
FIGS. 11 and 12
. The lockconnectors
124
each have a lockconnector male part
126
which is affixed to the gunwale
104
and a lockconnector female part
128
which is affixed to the rib
122
. The rib
122
is installed by fitting the lockconnector female part
128
into engagement with the lockconnector male part
126
and pivoting the rib
122
to lock the lockconnector male part
126
and the lockconnector female part
128
together, as shown in FIG.
12
. The interlocking of the lockconnector male part
126
and the lockconnector female part
128
provides a secure connection of the rib
122
to the gunwale
104
.
The keel stringer
114
is secured to the ribs
122
, as are several longitudinal stringers
130
positioned on the bottom and sides of the frame
102
. The frame
102
also has thwarts
132
which are affixed to a selected subset of the ribs
122
to stabilize the gunwales
104
.
The collapsible canoe
100
has a skin
134
which covers the frame
102
and is supported thereon. The skin
134
has a pair of gunwale sleeves
136
which engage the gunwales
104
of the frame
102
to secure the skin
134
to the frame
102
. The skin
134
also has a pair of side panels
138
attached to the gunwale sleeves
136
, and a bottom panel
140
which is attached to the side panels
138
. The side panels
138
are attached to each other and to the bottom panel
140
at a bow seam region
142
and a stem seam region
144
.
In the collapsible canoe
100
of the '634 patent, the skin
134
is provided with anti-flex covers
146
which are bonded to the side panels
138
on either side so as to form envelopes. A multi-chambered anti-flex air bladder
148
resides in each of the envelopes formed by the anti-flex covers
146
, and the anti-flex air bladders
148
are inflated to provide means for tensioning the skin
134
. The combination of the anti-flex covers
146
and the anti-flex air bladders
148
is also intended to provide greater rigidity to the collapsible canoe
100
. Since the anti-flex covers
146
must be bonded to the side panels
138
in order to anchor the anti-flex air bladders
148
to the skin
134
, fabrication of the skin
134
is complicated and more expensive.
The frame
102
of the collapsible canoe
100
of the '634 patent is intended to be a free-standing, isotropically secure structure, which is achieved through the securing of the elements of the frame
102
together. While the frame
102
of the '634 patent may provide enhanced rigidity and structural integrity which is independent of the skin
134
, such is of limited value, since the skin
134
must always be part of the collapsible canoe
100
, and securing of the frame elements can be achieved through interaction between the skin
134
and the frame
102
. Failure of the skin
134
will still make the collapsible canoe
100
unseaworthy. The difficulty and cost of fabrication of the collapsible canoe
100
is increased by the large number of connectors which are required to secure the frame elements together. Additionally, the large number of connectors greatly complicates assembly and disassembly of the collapsible canoe
100
. Furthermore, the connectors are typically affixed to the frame members with rivets or pins, and the large number of holes required to accommodate multiple connectors being so attached significantly weakens the structural elements of the frame
102
.
In addition to the disadvantages set forth above, the collapsible canoe
100
may still be liable to failure of the gunwale sleeves
136
. While the frame
102
is intended to be free-standing and somewhat rigid, the '634 patent teaches that the rigidity of the collapsible canoe
100
may be adjusted by varying the pressure in the anti-flex air bladders
148
, indicating that there is still a significant amount of flexibility in the frame
102
. This flexibility may tend to cause upwards forces F
2
on the stem elements
118
, which again are transmitted to the gunwale sleeves
136
in the manner discussed above with regard to the collapsible canoe
50
, and again may result in failure of the gunwale sleeves
136
.
Thus, there is a need for a collapsible canoe which provides ease of fabrication, assembly, and disassembly, which overcomes the problems of failure of the gunwale sleeves due to upwards forces of the stem elements.
SUMMARY OF THE INVENTION
The present invention is a collapsible canoe which overcomes the problems discussed above. The collapsible canoe shares many features in common with prior art collapsible canoes, and has a frame which includes a pair of gunwales, each having a bow end and a stem end. A pair of gunwale terminators connect the bow ends and the stem ends of each of the gunwales. At least one thwart is connected to the gunwales to maintain a separation therebetween. The frame also includes a series of ribs, each supported against the gunwales by gunwale-engaging clips. A keel stringer and supplemental bottom stringers traverse the ribs. A pair of stem elements are attached to and terminate the keel stringer, each being configured such that, when attached to the keel stringer, a stem end region of the stem element resides in close proximity to one of the gunwale terminators. The supplemental bottom stringers terminate at each end in a bottom stringer terminator which is affixed to one of the stem elements.
The collapsible canoe has a skin which covers the frame and is supported thereon. The skin has a pair of gunwale sleeves which engage the gunwales of the frame to secure the skin to the frame. The skin also has a pair of side panels which attach to the gunwale sleeves or may be formed integrally therewith, and a bottom panel which is attached to the side panels. Preferably, the bottom panel is provided with a bottom foam lining to minimize abrasion of the bottom panel. A pair of terminator panels connect the side panels to each other and to the bottom panel at each end of the collapsible canoe.
Means for tensioning the skin are provided. In one embodiment, the means for tensioning the skin are provided by a pair of inflatable compartments which are similar to those discussed above with respect to the prior art collapsible canoes (
10
and
50
). Again, it is preferred to provide an inflatable compartment support rod on either side of the collapsible canoe to provide longitudinal support for the inflatable compartments.
In another embodiment, the means for tensioning the skin are provided by sizing the ribs and the skin such that the ribs tension the skin as they are installed by being pivoted to a vertical position. In this embodiment, side stringers are employed which are engaged by stringer-engaging clips attached to the ribs. Preferably, the side panels are provided with a side foam lining to minimize abrasion of the side panels.
Means for stabilizing the stem elements with respect to the gunwale terminators are also provided. The means for stabilizing the stem elements attach to the stem elements of the frame and to the terminator panels of the skin to prevent upward movement of the stem end regions with respect to the terminator panels. This stabilizes the stem elements with respect to the gunwale terminators, since the gunwale terminators are stabilized with respect to the terminator panels by their engagement with the gunwale sleeves. Since upward motion of the stem end regions relative to the terminator panels is prevented, any upward force F
2
of the stem elements will be transferred to the terminator panels of the skin, rather than being accommodated by the gunwale terminators which stresses the gunwale sleeves. The terminator panels are typically constructed sufficiently strong as to be able to readily accommodate such upward forces.
In one preferred embodiment, the means for stabilizing the stem elements is provided by a pair of prongs, each of which is affixed to one of the pair of stem elements. Preferably, the prong is attached to the stem element at the stem end region. A slot is provided in each of the terminator panels, positioned to engage one of the prongs. Engagement between the prong and the slot stabilizes the prong by preventing upward movement of the prong relative to the slot, thereby stabilizing the stem elements with respect to the gunwale terminators.
In another preferred embodiment, the means for stabilizing the stem elements is provided by a pair of straps attached to the pair of terminator panels, in combination with means for fastening the pair of straps to the pair of stem elements. The strap passes over the gunwale terminator and the stem end region of the frame and is tightly secured with respect to the stem element such that the strap prevents upward motion of the stem end region with respect to the terminator panel, thereby stabilizing the stem elements with respect to the gunwale terminators.
Preferably, the means for fastening the pair of straps to the pair of stem elements are provided by anchoring means affixed to each of the stem elements in combination with means for adjustably engaging the straps with the anchoring means. Means for adjustably engaging the straps allow adjustability to accommodate slight manufacturing variations in the skin.
Because upward forces F
2
of the stem elements are transferred to the terminator panels of the skin, there is no requirement to connect the gunwale terminator to the stem elements. However, it is preferred for the stem elements to each be provided with a gunwale terminator cradle which is configured to supportably engage one of the gunwale terminators to prevent upward movement of the stem end region relative to the gunwale terminator. Such engagement of the stem element with the gunwale terminator allows stresses due to upward forces F
2
of the stem element to be shared by the terminator panel and the gunwale sleeves. This minimizes the stresses on either element, and provides an extra degree of safety through redundancy. In the case of failure of the terminator panel, the stem element will be maintained in position temporarily by the gunwale sleeves, gunwales, and gunwale terminator until the collapsible canoe can be brought back to land and repaired.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is an isometric view illustrating a prior art collapsible canoe having a frame covered by a skin. The frame has a pair of gunwales connected together by gunwale terminators. The frame also has stem elements, each secured to one of the gunwale terminators by a gunwale terminator securing strap.
FIG. 2
is a detail view of the frame of the collapsible canoe shown in
FIG. 1
, showing the connection of a rib to one of the gunwales. A gunwale-engaging clip supports the rib against the gunwale, and the gunwale and the rib are secured together by tension of the skin.
FIG. 3
is a detail view of a bottom stringer terminator employed in the collapsible canoe illustrated in
FIGS. 1 and 2
.
FIG. 4
is an enlarged view of the region
4
of
FIG. 1
, showing details of the connection of one of the stem elements to one of the gunwale terminators.
FIG. 5
is a section view showing one end of another prior art collapsible canoe which is similar to the collapsible canoe shown in
FIGS. 1 through 4
. In this collapsible canoe the frame has a stem element which engages the gunwale terminator but is not secured thereto. The collapsible canoe also employs a skin having terminator panels at the ends and employs inflatable compartment support rods to improve the appearance of the collapsible canoe.
FIG. 6
is a view of section
6
—
6
of
FIG. 5
, showing forces on the stem element which can cause failure of gunwale sleeves of the skin which engage the gunwales of the frame.
FIG. 7
is an exploded view of the portion of the skin at the bow end of the collapsible canoe illustrated FIG.
5
. The terminator panel in this embodiment is provided by an extension of the bottom panel.
FIG. 8
is detail view of the region
8
of
FIG. 6
, showing additional details of the stem and the gunwale terminator.
FIG. 9
is a perspective view of another prior art collapsible canoe, which has a free-standing, standing, isotropically secure frame covered by a skin.
FIG. 10
is a detail view of a portion of the frame of the prior art collapsible canoe shown in
FIG. 9
, showing the connection of a stem element to a gunwale terminator. The stem element is secured to the gunwale terminator by a gunwale fastener and a securing strap to provide an isotropically secure connection.
FIG. 11
is a detail view showing male and female parts of a rib-gunwale lockconnector which is employed in the collapsible canoe shown in
FIG. 9
to secure the ribs to the gunwales. The male female parts are shown prior to being locked together.
FIG. 12
is a detail view showing the male and female parts of the rib-gunwale lockconnector shown in
FIG. 11
after they have been locked together.
FIG. 13
is a section view of one embodiment of the present invention, which corresponds to the view shown in FIG.
6
. In this embodiment, the stem element is provided with a prong which engages a slot in a terminator panel of the skin. The slot is positioned to stabilize the prong, thereby stabilizing the stem element with respect to the gunwale terminator. Inflatable compartments are provided for tensioning the skin.
FIG. 14
is a detailed view of the region
14
of
FIG. 13
, showing details of the prong and the slot.
FIG. 15
is a view which corresponds to the view of
FIG. 14
, showing details of another embodiment of the present invention. In this embodiment, the stem element is provided with both a gunwale terminator cradle for supporting the gunwale terminator and a prong which engages a slot in the terminator panel.
FIG. 16
is a partial view of the embodiment shown in FIG.
15
. This embodiment employs auxiliary ribs which may optionally replace a selected subset of the ribs in order to change the handling characteristics of the collapsible canoe.
FIG. 17
is a view of one of the ribs of the collapsible canoe shown in
FIGS. 15 and 16
, along with a corresponding one of the auxiliary ribs.
FIG. 18
is a section view of another embodiment of the present invention. In this embodiment, a strap is attached to the terminator panel, and means for fastening the strap to the stem element are provided. This embodiment also employs ribs which are sized to provide means for tension as they are installed.
FIG. 19
is a detailed view of the region
19
of
FIG. 18
, showing details of the strap and the stem element. A detaching buckle connected to an anchor strap provides means for fastening the strap respect to the stem element.
FIG. 20
is a view of an alternative embodiment to that shown in FIG.
19
. In this embodiment, a D-ring attached to the stem element provides anchoring means, while a ladderlock lock buckle provides means for adjustably engaging the strap with the D-ring.
FIG. 21
is a view of a portion of a skin which may be employed as an alternative to the skins shown in
FIGS. 13 through 15
. In this embodiment, the side panels are attached to each other and to the bottom panel at an end seam. A heat sealable tape is applied over the end seam to provide a terminator panel. A slot is provided in the terminator panel and in the end seam, for engaging a prong such as is shown in
FIGS. 14 and 15
.
BEST MODE FOR CARRYING THE INTO PRACTICE
FIG. 13
is a section view showing one end of a collapsible canoe
200
forming one embodiment of the present invention, the view corresponding to the view shown in FIG.
6
. It should be appreciated that the other end of the collapsible canoe
200
is similar to the end shown. The collapsible canoe
200
shares many features in common with the prior art collapsible canoe
50
discussed above. The collapsible canoe
200
has a frame
202
which includes a pair of gunwales
204
(only one of which is shown), each having a bow end
206
and a stern end (not shown). A gunwale terminator
208
connects the bow ends
206
of the gunwales
204
together. Similarly, although not shown, another gunwale terminator
208
connects the stern ends of the gunwales
204
together. A series of ribs
210
are attached to the gunwales
204
by gunwale-engaging clips
212
. A thwart
214
is connected to the gunwales
204
to maintain a separation between the gunwales
204
. Again, in the embodiment shown, the thwart
214
is attached to the rib
210
′.
A keel stringer
216
traverses the ribs
210
and is centrally positioned with respect to the gunwales
204
. The frame
202
also has supplemental bottom stringers
218
which traverse the ribs
210
. Again, the ribs
210
are provided with stringer-engaging clips
220
to maintain the keel stringer
216
and the supplemental bottom stringers
218
in position. A stem element
222
terminates the keel stringer
216
, and extends up to a stem end region
224
which resides near the gunwale terminator
208
. The supplemental bottom stringers
218
terminate at bottom stringer terminators
226
which are attached to the stem element
222
.
The collapsible canoe
200
has a skin
228
having a pair of gunwale sleeves
230
(only one of which is shown) which engage the gunwales
204
of the frame
202
. A pair of side panels
232
(one of which is only partially shown) attach to the gunwale sleeves
230
. A bottom panel
234
is attached to the side panels
232
, and a terminator panel
236
connects the side panels
232
to each other and to the bottom panel
234
.
Means for tensioning the skin are provided by a pair of inflatable compartments
238
(one of which is shown) which are similar to the inflatable compartments
86
discussed above.
Means for stabilizing the stem element
222
with respect to the gunwale terminator
208
are provided in the collapsible canoe
200
. As shown in the detail view of
FIG. 14
, the means for stabilizing the stem element
222
are provided by a prong
240
, which is affixed to the stem end region
224
of the stem element
222
, and a slot
242
in the terminator panel
236
. The slot
242
is positioned to engage the prong
240
. When the prong
240
and the slot
242
are so engaged, upward movement of the prong
240
relative to the slot
242
is prevented, thereby stabilizing the prong
240
with respect to the slot
242
. This stabilization of the prong
240
stabilizes the stem element
222
to which it is attached with respect to the terminator panel
236
, thereby stabilizing the stem element
222
with respect to the gunwale terminator
208
, which is itself stabilized with respect to the terminator panel
236
by the engagement of the gunwales
204
with the gunwale sleeves
230
and the tension in the skin
228
. Any upward force F
2
of the stem element
222
is transferred to the terminator panel
236
by the engagement of the prong
240
with the slot
242
.
It should be noted that, in the collapsible canoe
200
, the gunwale terminator
208
is not directly connected to the stem element
222
. Such direct connection is not necessary, since upward forces F
2
of the stem element
222
are accommodated by the terminator panel
236
, rather than by the gunwale terminator
208
. Such an arrangement avoids stresses on the gunwale sleeves
230
, but failure of the terminator panel
236
may result in a loss of structural integrity of the collapsible canoe
200
. The construction of the terminator panel
236
is typically sufficiently strong as to avoid being prone to failure, but an arrangement where failure of the terminator panel
236
can be accommodated may be desirable for use in extreme conditions, such as uses where the terminator panel
236
is exposed to severe abrasion.
FIG. 15
is a view which corresponds to the view of
FIG. 14
, illustrating a portion of a collapsible canoe
250
which provides redundancy in accommodating upward forces. The collapsible canoe
250
again has a pair of gunwales
252
(only one of which is shown), each having a bow end
254
connected to a gunwale terminator
256
. A stem element
258
extends up to a stem end region
260
near the gunwale terminator
256
. A gunwale terminator cradle
262
is provided on the stem end region
260
. The gunwale terminator cradle supportably engages the gunwale terminator
256
to prevent upward motion of the stem element
258
with respect to the gunwale terminator
256
.
The collapsible canoe
250
has a skin
264
having a pair of gunwale sleeves
266
(only one of which is shown) attached to a pair of side panels
268
, which in turn are connected together by a terminator panel
270
.
Means for stabilizing the stem element
258
with respect to the gunwale terminator
256
are provided by a prong
272
, which in this embodiment is affixed to the gunwale terminator cradle
262
, and a slot
274
in the terminator panel
270
which is positioned to engage the prong
272
. The engagement of the stem element
258
with the gunwale terminator
256
and the prong
272
with the slot
274
allows stresses due to upward forces F
2
of the stem element
258
to be shared by the terminator panel
270
and the gunwale sleeves
266
. This minimizes the stresses on either element, and provides an extra degree of safety through redundancy. If the terminator panel
270
fails, the stem element
258
is maintained in position by the gunwale sleeves
266
, the gunwales
252
, and the gunwale terminator
256
until the terminator panel
270
can be repaired.
FIG. 16
is a view of one end of the frame elements of the collapsible canoe
250
. The collapsible canoe
250
differs further from the collapsible canoe
200
in that the collapsible canoe
250
has both a series of ribs
280
, and a set of auxiliary ribs
282
, one of which is shown in phantom in FIG.
16
. The set of auxiliary ribs
282
correspond to a subset of the ribs
280
, and may be substituted for the corresponding ribs
280
to alter the shape of the collapsible canoe
250
.
FIG. 17
compares a rib
280
′ with its corresponding auxiliary rib
282
′. To assure that the skin
264
remains correctly fitted to the ribs
280
and auxiliary ribs
282
of the collapsible canoe
250
, it is necessary for the rib
280
′ and the rib
282
′ to both have a common rib length L. However, while the rib length L of both the rib
280
′ and the auxiliary rib
282
′ is the same, the rib
280
′ defines a first beam B
1
and a first depth D
1
, while the auxiliary rib
282
′ defines a second beam B
2
and a second depth D
2
which are respectively different from the first beam B
1
and the first depth D
1
.
Since the handling characteristics of the collapsible canoe
250
are largely dependent on the beam and depth, altering these dimensions alters the handling characteristics of the collapsible canoe
250
. In the example illustrated, the first beam B
1
is greater than the second beam B
2
, and the first depth D
1
is less than the second depth D
2
. These relative dimensions make the collapsible canoe
250
broader and more stable when the ribs
280
are exclusively employed, and narrower and faster when the selected subset of the ribs
280
have been replaced by auxiliary ribs
282
. For use with inexperienced canoeists, exclusive use of the ribs
280
provides a stable configuration of the collapsible canoe
250
which is less liable to capsizing. For more skilled canoeists, who may demand greater performance, use of the auxiliary ribs
282
in place of the corresponding ribs
280
provides a configuration of the collapsible canoe
250
which offers greater speed with less stability. It has been found practical for the first beam B
1
to be up to about three inches greater than the second beam B
2
, and the first depth D
1
to be up to about 1½ inches less than the second depth D
2
. These changes in the relative dimensions provide a significant change in handling characteristics while maintaining the fit of the skin
264
.
It should be noted that, as indicated in
FIG. 16
, it is not necessary to replace all of the ribs
280
with auxiliary ribs
282
. Typically, only the ribs
280
which reside in the central regions of the collapsible canoe
250
will be replaced with auxiliary ribs
282
. It has been found that in a fourteen foot model of the collapsible canoe
250
having eight ribs
280
, only the four central ribs
280
need be replaced with auxiliary ribs
282
to alter the handling characteristics. Similarly, in a fifteen foot model having nine ribs
280
, only the central five ribs
280
need be replaced with auxiliary ribs
282
. Thus, the auxiliary ribs
282
allow a user to effectively have two different collapsible canoes
250
, with different handling characteristics, with little more weight or storage space requirements than a single collapsible canoe
250
, since only a small number of auxiliary ribs
282
are added.
FIGS. 18 and 19
illustrate another embodiment of the present invention, a collapsible canoe
300
, and correspond respectively to the views of
FIGS. 13 and 14
. The collapsible canoe
300
again has a frame
302
having a pair of gunwales
304
(one of which is shown), each having a bow end
306
and a stern end (not shown). A gunwale terminator
308
connects the bow ends
306
and the stem ends of each of the gunwales
304
together. The frame
302
also has a series of ribs
310
and athwart
312
.
A keel stringer
314
and supplemental bottom stringers
316
traverse the ribs
310
. A stem element
318
terminates the keel stringer
314
. The supplemental bottom stringers
316
terminate at bottom stringer terminators
320
. Side stringers
322
(only one of which is shown) are provided, which also traverse the ribs
310
. Stringer engaging clips
324
on the ribs
310
engage the keel stringer
314
, the supplemental bottom stringers
316
, and the side stringers
322
to maintain them in position relative to the ribs
310
.
The collapsible canoe
300
has a skin
326
having a pair of gunwale sleeves
328
(one of which is shown), a pair of side panels
330
(one of which is only partially shown), a bottom panel
332
, and a terminator panel
334
. Preferably, the bottom panel
332
is provided with a bottom foam lining
336
, while the side panels
330
are each provided with a side foam lining
338
to minimize abrasion of the skin
326
.
Means for tensioning the skin
326
are provided by the ribs
310
. When installed, the ribs
310
are each engaged with the gunwales
304
at an angle, as indicated in phantom. Typically the side stringer
322
is positioned to engage the stringer-engaging clips
324
on the rib
310
at this point. The rib
310
is then pivoted to a vertical position, gradually increasing the tension of the skin
326
as the rib
310
approaches the vertical position. Locking clips
339
are preferably mounted to a subset of the supplemental bottom stringers
316
. Such locking clips
339
are known in the art, and engage the corresponding stringer-engaging clips
324
on each rib
310
to maintain each rib
310
in its vertical position.
It should be noted that the ribs
310
must be carefully sized relative to the skin
326
in order to provide the means for tensioning the skin
326
. Optionally, an alternate set of ribs could be employed which are smaller in size than the ribs
310
, and inflatable compartments (not shown) could be employed to provide the means for tensioning the skin
326
. The option of using two or more separate sets of different sized ribs allows modifying the shape and handling characteristics of the collapsible canoe
300
.
Means for stabilizing the stem element
318
with respect to the gunwale terminator
308
are provided. In the collapsible canoe
300
, the means for stabilizing the stem element
318
are provided by a strap
340
attached to the terminator panel
334
in combination with means for fastening the strap
340
to the stem element
318
. In the embodiment illustrated, the means for fastening the strap
340
include anchoring means affixed to the stem element
318
in combination with means for adjustably engaging the strap
340
with the anchoring means.
The anchoring means are provided by an anchor strap
342
which is attached to the stem element
318
. The means for adjustably engaging the strap
340
with the anchor strap
342
are provided by a detaching buckle
344
.
The detaching buckle
344
has a buckle female part
346
and a buckle male part
348
, which are detachably engaged with each other. Such detaching buckles are known in the art, and it is preferred for the detaching buckle
344
to have an activating button
350
for causing detachment of the buckle female part
346
from the buckle male part
348
. The buckle female part
346
is attached to the strap
340
, while the buckle male part
348
is adjustably engaged by an anchor strap
342
. The strap
340
passes over the gunwale terminator
308
, and the buckle female part
346
and buckle male part
348
are engaged with each other. The anchor strap
342
is threaded through the buckle male part
348
and adjusted with respect to the buckle male part
348
to tightly secure the strap
340
and the buckle female part
346
with respect to the stem element
318
. Once the position of the anchor strap
342
with respect to the buckle male part
348
is adjusted, the buckle female part
346
and the buckle male part
348
may be readily attached or detached from each other without further adjustment, facilitating assembly and disassembly of the collapsible canoe
300
.
The fastening of the strap
340
to the stem element
318
prevents upward motion of the stem element
318
with respect to the terminator panel
334
, thereby stabilizing the stem element
318
with respect to the gunwale terminator
308
. Preferably, the stem element
318
is provided with a gunwale terminator cradle
352
for engaging the gunwale terminator
308
.
FIG. 20
is a view which corresponds to the view of
FIG. 19
, illustrating a portion of a collapsible canoe
300
′ which employs an alternative means for securing the strap
340
. In this embodiment, the means for fastening the strap
340
again include anchoring means affixed to the stem element
318
combined with means for adjustably engaging the strap
340
with the anchoring means.
The anchoring means in this embodiment are provided by a D-ring
360
which is attached to the stem element
318
. The means for adjustably engaging the strap
340
with the D-ring
360
are provided by a ladder-lock buckle
362
which is adjustably engaged by the strap
340
.
To fasten the strap
340
with respect to the stem element
318
, the strap
340
is threaded through the ladder-lock buckle
362
, passed through the D-ring
360
, and then rethreaded through the ladder-lock buckle
362
. The ladder-lock buckle
362
is configured to taughtly engage the strap
340
when it is so threaded, in the manner which is well known in the art.
FIG. 21
is a view of a portion of a skin
400
which may be employed as an alternative to the skins (
228
,
264
) shown in
FIGS. 13 through 15
. The skin
400
has a pair of gunwale sleeves
402
(only one of which is shown), a pair of side panels
404
attached to the gunwale sleeves
402
, and a bottom panel
406
which is attached to the side panels
404
.
In the skin
400
, the side panels
404
are attached to each other and to the bottom panel
406
at an end seam
408
. A terminator panel
410
is provided by a heat sealable tape applied over the end seam
408
, and serves to secure the side panels
404
to each other and to the bottom panel
406
.
A slot
412
is provided in the terminator panel
410
, and also extends through the end seam
408
. The slot
412
is positioned for engaging a prong such as the prongs (
240
,
272
) shown in
FIGS. 14 and 15
.
While the novel features of the present invention have been described in terms of particular embodiments and preferred applications, it should be appreciated by one skilled in the art that substitution of materials and modification of details obviously can be made without departing from the spirit of the invention.
Claims
- 1. A collapsible canoe comprising:a pair of gunwales, each having a bow end and a stern end; a pair of gunwale terminators which are configured to engage said bow ends and said stern ends; a series of ribs connected to said pair of gunwales by gunwale-engaging clips; at least one thwart which engages said pair of gunwales to maintain a separation therebetween; a keel stringer which traverses said series of ribs; supplemental bottom stringers which traverse said series of ribs; a pair of stem elements which attach to said keel stringer and extend to said pair of gunwale terminators; bottom stringer terminators which are affixed to said pair of stem elements and which engage said supplemental bottom stringers; a skin having, a pair of gunwale sleeves, each of which slidably engages one of said pair of gunwales, a pair of side panels which attach to said pair of gunwale sleeves, a bottom panel attached to said pair of side panels, and a pair of terminator panels which secure said pair of side panels with respect to each other and said bottom panel; means for tensioning said skin; and means for stabilizing said pair of stem elements with respect to said pair of gunwale terminators, which attach to said pair of stem elements and to said pair of terminator panels.
- 2. The collapsible canoe of claim 1 wherein said pair of terminator panels are provided by extensions of said bottom panel, to which said pair of side panels are attached.
- 3. The collapsible canoe of claim 1 wherein said means for tensioning said skin comprises:inflatable compartments positioned between said pair of side panels and said series of ribs.
- 4. The collapsible canoe of claim 3 wherein said means for tensioning said skin further comprises:a pair of inflatable compartment support rods which slidably engage said series of ribs and reside between said supplemental bottom stringers and said pair of gunwales.
- 5. The collapsible canoe of claim 1 further comprising:a set of auxiliary ribs which may be optionally employed in place of a selected subset of said series of ribs, each of said set of auxiliary ribs corresponding to one of said ribs of said selected subset of said series of ribs, each of said set of auxiliary ribs having a rib length L which is shared by said corresponding one of said ribs.
- 6. The collapsible canoe of claim 1 wherein said means for tensioning said skin is provided by sizing said series of ribs relative to said skin such that said ribs tension said skin as they are pivoted into position.
- 7. The collapsible canoe of claim 6 further comprising:locking clips attached to at least one of said supplemental bottom stringers, said locking clips engaging said ribs when said ribs are pivoted into position to maintain said ribs in such position.
- 8. The collapsible canoe of claim 7 further comprising:a pair of side stringers which slidably engage said series of ribs and reside between said supplemental bottom stringers and said pair of gunwales.
- 9. The collapsible canoe of claim 8 wherein each of said pair of side panels comprises:a side foam lining of a compliant material.
- 10. The collapsible canoe of claim 1 wherein said means for stabilizing said pair of stem elements further comprises:a prong fixably attached to each of said pair of stem elements; and a slot positioned in each of said pair of terminator panels, said slot being positioned so as to engage one of said prongs to stabilize said prong, thereby stabilizing said pair of stem elements with respect to said pair of gunwale terminators.
- 11. The collapsible canoe of claim 10 wherein said means for stabilizing said pair of stem elements further comprises:a gunwale terminator cradle provided on each of said pair of stem elements, said gunwale terminator cradle being configured to supportably engage one of said pair of gunwale terminators.
- 12. The collapsible canoe of claim 1 wherein said means for stabilizing said pair of stem elements further comprises:a pair of straps attached to said pair of terminator panels; and means for fastening said pair of straps to said pair of stem elements.
- 13. The collapsible canoe of claim 12 wherein said means for fastening said pair of straps to said pair of stem elements further comprises:anchoring means affixed to each of said pair of stem elements; and means for adjustably engaging each of said pair of straps with said anchoring means.
- 14. The collapsible canoe of claim 13 wherein said anchoring means further comprises:an anchor strap affixed to each of said pair of stem elements, and further wherein said means for adjustably engaging each of said pair of straps with said anchoring means further comprises:a pair of detaching buckles, each having, a buckle first part which is attached to one of said pair of straps, a buckle second part which is adjustably engaged by one of said anchor straps, and means for detachably engaging said buckle first part and said buckle second part with each other.
- 15. The collapsible canoe of claim 13 wherein said anchoring means further comprises:a D-ring affixed with respect to each of said pair of stem elements, and further wherein said means for adjustably engaging each of said pair of straps with said anchoring means further comprises:a pair of ladder-lock buckles, each of which is adjustably engaged with one of said pair of straps.
- 16. The collapsible canoe of claim 1 wherein said pair of side panels are attached to each other and to said bottom panel at end seams, further wherein said pair of terminator panels are provided by heat sealable tape applied over said end seams.
- 17. The collapsible canoe of claim 16 wherein said means for stabilizing said pair of stem elements further comprises:a prong fixably attached to each of said pair of stem elements; and a slot positioned in each of said pair of terminator panels and extending through one of said end seams, said slot being positioned so as to engage one of said prongs to stabilize said prong, thereby stabilizing said pair of stem elements with respect to said pair of gunwale terminators.
- 18. The collapsible canoe of claim 17 wherein said means for stabilizing said pair of stem elements further comprises:a gunwale terminator cradle provided on each of said pair of stem elements, said gunwale terminator cradle being configured to supportably engage one of said pair of gunwale terminators.
US Referenced Citations (4)