Note: Descriptions are shown in the official language in which they were submitted.
CA 02494472 2005-O1-27
1
82704.902
Collapsible Fabric Structures
The present specification relates to collapsible,
fabric structures, for example, tents, children~s play
structures, tunnels and shade structures having an
igloo/dome tent shape.
to A foldable tent structure having an igloo/dome tent
shape is known from US Patent 2,167,219. It discloses
a foldable tent with a generally circular base made
from four rod segments. Two further arcuate rods are
provided hinged to the base rods to support a fabric ,
canopy. The structure is erected by folding out the
structure like a fan and linking the rods of the base
together to form a continuous loop.
A problem with the structure is that it is bulky to
2o carry as the arcuate rods that support the canopy are
long, rigid, semi-circular rods. If the rods were
removed from the fabric canopy then they would be
difficult to feed back into their locating fabric
- pockets.
The present invention presents a solution to this
problem by providing a structure of similar external
shape that can be readily assembled from a more
compact storage configuration, for example, a storage
3o configuration suitable for shipping and marketing of
the product.
Igloo/dome tents which use collapsible rods, for
example, made of fibre reinforced resins, have become
3s popular for camping and these can take many forms. At
a campsite it is necessary to assemble the collapsible
rods into long flexible frame members which are then
CA 02494472 2005-O1-27
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fed into sleeves or pockets that connect the fabric of
the tent to the frame members. The fabric induces a
curve in the frame members and it can be difficult to
feed these members into the sleeves or pockets because
of friction and snagging. The base of the structure
can also lack form at this stage and this can also
make it difficult to insert the frame members. In
some instances, users may peg out the base of their
tent to assist with the insertion of the frame
1o members.
.:
Other igloo/dome tents have become available recently
that are based on frame members in the form of
coilable loops. In many instances these can self-
erect upon release from their storage configuration
with little or no intervention by the camper. US-A-
4,858,634, US-A-5,163,461, US-A-5,337,772 and US-A-
6,363,955 are examples of these. These tent
structures, however, are complicated and expensive to
2o manufacture. In addition, many users are not able to
follow the instructions to collapse these structures
back into their most compact configuration in which
they are coiled up into a loop a third of the size of
the expanded loop structure. Users may also lose the
instructions after purchase and not be able to figure
out how to fully collapse the structures. This non-
coiling is particularly a problem with play structures
intended for indoor use that are of a much smaller
scale than the adult equivalents, as their partially
3o folded condition where the frame members are simply
folded together and not coiled may be seen ast"small
enough", for example, to store behind a sofa or in a
cupboard.
Therefore a problem recognised in the present
invention with these more technical structures is that
their more intricate construction is often not being
CA 02494472 2005-O1-27
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used properly by the end user and so represents
unnecessary complication which can confuse the end
user.
According to a first invention there is provided a
collapsible fabric structure in the form of an igloo/
dome tent having a base frame member and at least two
additional canopy supporting frame members extending
as arches from common points on the base frame member
to to support the fabric canopy of the tent, wherein the
canopy supporting frame members each comprise a
plurality of rods that are connected together and fed
into means (for example sleeves, loops or pockets)
which locate the fabric to the frame members and force
the frame members into an arcuate form, and wherein
the base frame member comprises a resilient member in
the form of a loop which extends around substantially
the perimeter of the structure to expand the base upon
release from a collapsed configuration.
An advantage of the structure of the present invention
is that the loop base frame member provides form to
the structure prior to the insertion of the canopy
~ supporting frame members. This makes it easier for
the user to locate the frame members in the sleeves,
loops or pockets and slide them into the fabric
structure.
The user will also be familiar with the way the rods
of the canopy supporting frame members connect
together and feed into the sleeves, loops or pockets
of the fabric structure from existing igloo/dome tent
structures. After use, these frame members can be
extracted leaving the fabric structure with just a
resilient loop frame member in its base. The presence
of just a single coilable member, rather than two or
more coilable frame members, means that the tent can
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be coiled up into a more compact configuration with
greater ease and this may be within the capability of
the user even after the instructions have been lost.
If preferred, the structure may instead be simply
folded in half for storage purposes. The loop base
frame member is sufficiently resilient to allow the
loop to be folded in two. The arch-like canopy
supporting frame members hinge about the fold line,
to where the ends of these frame members meet the base
frame member ~a't the common points, so as to fold flat
against each other like the pages of a book. A
fastener, for example, in the form of Velcro, a tie, a
buckle, a push fastener, button, etc., may be provided
i5 to secure the structure in this partially collapsed
configuration.
The resilience of the base loop frame member means
that the structure is self-opening from this partially
2o collapsed configuration and provides some tension into
the fabric canopy. Preferably this is sufficient to
allow the structure to be used indoors, i.e., without
the aid of tent pegs. However, ties or pockets for
sand, for example, may also be provided to secure the
25 structure to the ground in the case of outdoor use.
These may also serve to pull the structure slightly
tauter.
Preferably the structure has a coilable member in the
3o form of a fibre reinforced resin wire, more preferably
an epoxy based wire, and in particular one iri~which at
least the surface layer of fibre is~wound helically
around the core of the wire. The wire is preferably
between 1 and 4 mm in diameter, more preferably 2-3
35 mm, and readily deformable to allow it to be coiled
easily. It is also envisaged that a resilient strip,
e.g., of steel can be used to form the loop, although
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this is seen as less desirable for play structures
than the fibre reinforced resin wire because it may
present a sharp edge in the base which could hurt a
young child and can be more difficult to coil up.
5
The base may be generally circular or a more complex
ornamental shape, for example, including features to
replicate the appearance of a flower, animal, insect,
bird etc. However more preferably the base has a
to substantially oval perimeter with major and minor
axes. In such arrangements the structure will fold
about the minor axis to bring the ends of the
structure (the ends of the major axis) together.
Where a more complex ornamental shape is adopted, the
base frame member may extend around the perimeter of
the design, or more preferably in an oval shape within
but still relatively close to the edge of the
structure. For example, petals of a flower design
could be created by providing additional curved areas
of fabric extending out from the base frame member.
Preferably the base of the structure can be coiled
into three loops once the canopy supporting members
have been removed. This will reduce the base to
approximately one third of its size. Fastening means,
for example, snap fasteners, straps, ties, Velcro,
zips etc may be provided to retain the structure in a
fully collapsed configuration. This can help hold the
structure in a compact form for ease of putting it
3o away into a storage bag.
Preferably the ends of three arch-like canopy
supporting frame members meet substantially where the
base frame member crosses the minor axis of the
elliptical base (the "common points"). The frame
members do not need to contact each other, though they
do need to be sufficiently close to transfer forces to
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hold the canopy in an expanded configuration. In such
arrangements there would be a central arch disposed
substantially perpendicular to the base and second and
third arches disposed to each side dividing the right
angle between the central arch and the base.
Arrangements are also envisaged where four or more
arch-like canopy supporting members are provided.
The structure may also include additional arch or
io other frame members that are hinged to the base at
positions betvteen a central fold line (the minor axis)
and an end of the base (an end of a major axis), for
example, as supports for doorways. Arch frame members
on one side of a centre line, e.g., the minor axis of
an oval base, should all hinge and fold flat in the
same direction, and all arch members on the other side
should all hinge and fold flat in the opposite
direction during folding together of the opposing end
portions.
The arch frame members may be made of a similar
material to the loop frame member. However,
conventional fibre reinforced resin rods, for example,
of between 2 to 4 mm in diameter and between 30 to 60
mm in length, are adequate for the purpose and provide
a cost effect solution to supporting the fabric
canopy. Connectable rods of this type, for example,
fitted with sleeves to provide male/female connections
are known from existing tent structures and so will be
3o familiar to the user in terms of assembly and
disassembly of the frame members. The ends of the
frame members may be fitted with pads to reduce
snagging and their respective receiving pockets may be
reinforced to prevent wear.
Preferably the base of the structure includes a floor
panel so that the interior space is enclosed from
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above and below. However, for certain applications it
may be desirable to dispense with the whole or a
portions) of the floor panel, for example, toy
structures where it is desirable to reduce
manufacturing costs or to provide amusement features.
In at least one of the ends, and preferably in both
ends, an entrance is provided to give access to the
interior. Entrances are preferably closable with a
1o door that can be fastened in its closed position.
Preferably such an entrance and door has an arcuate
edge with the base of the door remaining connected to
the base of the structure. This creates a partial
disc shaped mat when the door is opened and resting on
is the ground. In addition to the aesthetics, such an
arrangement avoids the creation of a potential trip
hazard for a young child. This may be important in a
structure having entrances in opposite ends and
functioning as a tunnel for the child to run or crawl
2o down. The floor panel may include additional detail
to continue features provided on the door, for
example, to give the appearance of a full disc at the
entrance to the structure. This may incorporate a
spiral pattern as an amusement feature for a child. A
- 25 zip may be provided as a means for closing the door or
other fastening means such as Velcro, snap fasteners,
ties, etc., may be used instead. A second entrance
and door may be provided of the same or a different
shape. An additional resilient member, e.g., in the
3o form of an arch, may be incorporated into the door
entrance to support the fabric when the door ~s open.
The term "fabric" is intended to cover any sheet-like
flexible material that might be used for such a
35 structure, for example, a woven fabric, film, netting,
transparent or coloured sheet material. The structure
may include windows of transparent or coloured
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material and may include openings and other features
as amusement features.
The new structure has great applicability for use as
play structures, for example, in the form of play
tents or tunnels. The structure can also be used in
full size structures for grown-ups.
The first invention uses the resilience of a flexible
to coilable frame member in the base of the structure to
open up the structure into an erected configuration.
The present specification also concerns other
structures having substantially the same shape, which
through a function of the base, also expand into an
erected structure.
One problem identified with the structures of US-A-
4,858,634, US-A-5,163,461 and US-A-5,337,772 is that
because of the position of the frame members and the
distribution of forces within the fabric of structure,
the entrances have to be located within the saddle of
the upper frame member. As a result, the base of the
entrance can present a trip hazard, for example, when
the structure is being used by a young child.
.
A solution to this problem is taught in US-A-
6,363,955. This discloses a further self-erecting
fabric structure having a coilable loop frame member
in a base and two additional frame members extending
3o at right angles to the base to support an upper canopy
of fabric. The two additional supports are also in
the form of loops and hinge with respect to the base
during erection of the structure. The resilience of
the base loop frame member is sufficient to extend the
end portions into a substantially planar arrangement,
and in so doing pulling the additional loops upright
and the fabric of the tent taut. The base of the
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structure is elliptical and the two additional frame
members hinge about axes which are parallel to the
minor axis but spaced approximately midway between the
minor axis and the ends of the structure that extend
in the direction of the major axis. Straps or webs of
fabric connecting these additional loops to the ends
of the base pull the loops into their substantially
upright configuration to hold the fabric in a tunnel
shape.
However a problem with this arrangement is that it
still requires straps to be present and a hinge to
extend across the entrance to the structure which
could pose trip hazards for young children or be
uncomfortable on their knees as they are crawling
through the structure.
Thus from a second invention disclosed herein, there
is provided a collapsible fabric structure in the form
2o of an igloo/dome tent having at least two canopy
supporting frame members extending as arches from
common points on a base of the structure to support
the fabric canopy of the tent, wherein the base
comprises an air chamber. Preferably the base can be
inflated to expand the structure from a storage
configuration to an erected configuration. In all
the embodiments of this invention, the inflated base
acts as a tensioning element to pull the fabric canopy
taut. It is also comfortable on the knees of young
3o children as they are crawling through the structure
and provides an amusement feature. For the ;
embodiments where poles are inserted after inflation
of the base, the air chamber provides the base with
necessary form and rigidity to make insertion of the
rods simpler, as with the first invention.
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The air chamber is inflated to give the base rigidity.
It is this rigidity and form that pulls the rest of
the structure into an erected configuration in a
similar way to inflatable bouncy castles. The air
5 chamber also acts as a mattress to provide a play
structure in the form of a tent that children can
sleep in or play in comfortably.
Apart from the replacement of the coilable base frame
1o member with an inflatable mattress, the second
invention is ~'ubstantially the same as the first
invention and the comments made above in relation to
the first invention apply equally to the second.
The base will need to be of about 4 to 15 cm thick,
preferably about 10 cm thick to accommodate the air
chamber. In one embodiment the air chamber is made of
plastic and retained within a fabric pocket of the
base of the structure. In another embodiment the air
2o chamber is an integral part of the structure. In yet
another embodiment, the air chamber is a fabric coated
material that is fixed to the rest of the structure.
The air chamber may also be removable from the rest of
the structure and connected to the structure by a
releasable connection, for example velcrQ~, press
fasteners, buttons, ties, straps and buckles, etc. In
still yet a further embodiment, the tent of the first
invention is provided with releasable connections to
attach an inflatable chamber to the base of the
structure.
a
Such an arrangement can also be achieved without the
base frame member and therefore according to yet a
further aspect this invention there is provided a
collapsible fabric structure in the form of an
igloo/dome tent comprising a fabric canopy, at least
two canopy supporting frame members extending as
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arches from common points on a base of the structure
to support the fabric canopy of the tent and a base
comprising an inflatable air chamber, wherein the
canopy supporting frame members and the canopy are
secured to the base by releasable connections so that
the base can be separated from the frame members and
canopy for storage purposes. In one arrangement, the
structure has the canopy supporting frame members
which pivot about the common points in relation to the
io base, wherein one side of the fabric canopy (i.e., a
portion extending from one common point around one end
of the base to the other common point) is provided
with releasable connections for detaching the fabric
canopy from the base. With one side detached from the
base, the fabric canopy can be folded down onto the
base by rotating the arches about their common points,
in a similar way to folding down a hood of a car.
An advantage of this embodiment, is that the
inflatable air chamber provides rigidity and form to
the structure. Once inflated, attachment of the
additional tent components is a relatively simple task
and it would be easy for the average person to work
out how to erect and disassemble the structure even if
the instructions had become lost. For his invention,
preferably the arches are semi-circular and the base
is circular.
For the second invention it has been found more
3o . preferable to use the helically bound fibre reinforced
epoxy wires or rods described above than the more
conventional tent pole materials. Other variants
include making the fabric canopy in two halves that
are connected at a suitable halfway point, for example
a central arch member. In this way, on the second
invention, the two halves can be connected to the
inflated base if they are not already fitted, and the
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canopy erected through manually pulling together the
two halves of the canopy together until the canopy is
pulled substantially taut against the rigidity of the
base.
A further development disclosed herein provides a
self-erecting, collapsible, fabric structure
comprising a base and a canopy of fabric to define an
interior within, the base having a resilient frame
Io member in the form of a loop extending around a
periphery the.~'eof, the base being substantially
elliptical and foldable about its minor axis such that
the end portions of the structure can be folded
together to collapse the structure, wherein the canopy
is supported by at least two additional frame members
which are in the form of arches that extend from the
base, the ends of each arch frame member being
positioned substantially on the minor axis such that
the arches are capable of hinging with respect to the
2o base so that they fold flat when the end portions of
the base are folded together.
The structure is self-erecting in the sense that it
will pop open into an expanded configuration upon
release from a collapsed configuration. .The base loop
frame member is resilient and therefore resists any
deflection out of a plane or neutral position. This
resilience provides a force on the rest of the
structure which is sufficient to expand it from a
3o collapsed configuration into an expanded configuration
and to pull the fabric of the canopy sufficiently taut
for use as a play structure. This development may
incorporate any of the features described in
connection with the other tents.
The present invention, in a broad aspect, then,
provides a tent comprising at least a frame and
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12a
a canopy, said frame comprising a base member
defining an outer periphery, and at least a pair
of arch members spanning said base member, said
base member being captive in said canopy, around
a :Lower peripheral edge thereof, and said arch
members being captive in said canopy over said
base member said canopy being dimensioned so as
to maintain tautness between said base member
and said arches.
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Certain preferred embodiments will now be described in
greater detail by way of example only and with
reference to the accompanying drawings, in which:
s Figure 1 shows a perspective view of a preferred
arrangement of the frame members for the tent with the
fabric canopy removed;
Figure 2 shows a side elevation of the tent of Figure
1 in cross-section;
Figure 3 shows an end view of the tent of Figure 1;
Figure 4 shows a side view of a second embodiment;
is
Figure 5 illustrates the construction of the base of
the tent of Figure 4;
Figure 6 shows the underside of the base of the tent;
Figure 7 shows the base with the fabric canopy stowed;
Figure 8 shows the erected tent viewed from one end;
Figure 9 shows the tent viewed from the Qther end; and
Figure 10 shows the tent from the opposite side to
that in Figure 4.
3o In Figure 1 there is shown a perspective view of a
preferred tent 1 structure according to the first
invention. The fabric canopy for the tent 1 has been
omitted for clarity. The structure in its most basic
form consists of a base frame member 2 and at least
two canopy supporting frame members 3 (in the
embodiment illustrated there are three) extending from
common points 4 of the base frame member 2.
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The base frame member 2 may consist of resilient metal
strip formed into a loop. The nature of the strip
profile means that the loop has a neutral position
when it is flat. Bending the loop out of this plane
is resisted by the resilience of the strip, which is
forced to bend and deflect to allow deflection out of
the plane. In the present invention, this resilience
provides the force to keep the structure in its
to erected or substantially erected configuration. In
other embodiments, a fibre reinforced member (wire or
rod) is used in place of the steel strip. Such
members tend to have a circular profile, which while
this has an effect on the deflection characteristics
because of the isotropic properties of the material,
it is preferred from the point of view of not
presenting a sharp edge at a location where a small
child could be crawling over. The most preferred
material of this type is manufactured by a company
2o called Sportex and takes the form of an epoxy wire
reinforced with longitudinal glass fibre or other
material and bound at its surface with a helically
wound thread. It has good all-round bend
characteristics without suffering from delamination
after repeated deflection. .
The base frame member 2 is preferably housed within a
sleeve that extends around the periphery of a floor
panel that forms the base of the tent 1. The
3o periphery constrains the base frame member 2 into a
circular form, or more preferably an oval shape as
shown with major axis A-A and minor axis B-B. The
floor panel (not shown) is preferably cut so that it
is pulled taut by the base frame member 2.
Three canopy supporting frame members (arches) 3 are
provided. A central arch 3 is positioned in a
CA 02494472 2005-O1-27
substantially upright configuration and two further
arches 3 are positioned either side inclined at an
angle a to the first one. The angle a is preferably
between 30 to 60 degrees and more preferably about 45
s degrees. All three canopy supporting frame members 3
are preferably of the same size and arranged to pivot
about their free ends 5 at the common points 4. In
this way the two inclined arches 3 can be pivoted
between a storage configuration where they are stacked
to flat side by side against the central arch, and an
erected configuration as shown in Figure 1 where they
are inclined to the central arch by an angle a.
The canopy supporting frame members 3 can be made of
15 any suitable frame material. It is preferred to use
conventional glass fibre rod material which has been
cut into transportable lengths and which can be joined
together to form the arches during the erection of the
tent from a cost point of view. Conventional metal
2o sleeves can be used as suitable connectors for this.
A set of rods may also be joined together by a length
of elastic material running through the middle of the
rods. Alternatively more exotic material such as the
helically bound rods described above can be used. In
such an embodiment, due to the bendability of the
material, the frame members 3 may consist of single
lengths of wire that remain housed within sleeves of
the structure during erection and collapsing of the
tent into a compact size for shipping.
Preferably the frame members 2,3 are housed w~.thin
sleeves sewn into the fabric canopy. However, as is
already known in the art, loops, pockets or any other
suitable feature may be used to secure the fabric to
the frame members 2,3. The sleeves may include
reinforced pockets at their ends to protect against
wear from the free ends 5 of the arches 3.
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The free ends 5 of the arches 3 are shown close
together at the common points 4 so that the points of
pivot allow the arches 3 to be folded flat against
each other and to provide a neat arrangement. However
the term "common point" 4 is used in a broad sense, in
that it is possible for the free ends 5 to be slightly
more spaced apart and for the arches to fold
approximately flat, but a better effect is achieved
1o when the free ends are positioned closer together and
so this is preferred. To collapse the tent 1 into a
storage configuration, the two ends of the base are
folded together like closing a book. If it is desired
to collapse the structure further then the arches 3
can be dismantled and the base frame member 2 coiled
into three loops. In the embodiments where coilable
material is used for the arches, then it may be
possible to leave these arches in place when coiling
up the structure.
As shown in Figure 1, two additional canopy supporting
frame members 6 are provided spaced from the free ends
5 of the other three arches 3. These secondary arches
,, 6 provide support to design features, for example a
doorway. These may be made of finer gauge material
than the primary arches 3. The arches are preferably
of a size and in a position where when they fold flat
against the central arch they adopt substantially the
same profile to provide a neat arrangement for
3o storage.
Figure 2 is a side elevation viewing the structure in
cross section along the major axis A-A. As shown, the
fabric canopy 7 is supported by the arches to create a
dome or igloo shape tent (a tent of substantially
hemispherical shape). The fabric canopy 7 is pulled
taut over the arches 3 by the resilience of the base
CA 02494472 2005-O1-27
17
frame member 2, the resilience urging the ends of the
tent 1 (the portion of the perimeter lying on the
major axis A-A) back into the neutral planar position.
The resilience should be sufficient to provide a
useable structure for indoor use. However, the tent 1
may also be provided with loops for tent pegs to allow
outdoor use too, and these may pull the fabric canopy
tauter. Pockets may also be provided for filling with
sand for use on a beach as an alternative to tent
to pegs. The fabric canopy 7 may incorporate different
materials, for example, netting or transparent
material to provide windows, and may incorporate
openings for children to view out of or climb out of.
Figure 3 illustrates the tent when viewed from one end
looking down the major axis A-A. In this figure a
doorway 8 can be seen, with the fabric immediately
adjacent the doorway 8 supported by one of the
secondary arches 6. As shown, preferably a semi-
2o circular doorway 8 is provided with a zip fastener 9
extending around the perimeter to close the door. The
door 8, when fully unzipped, can fold down flat like a
draw bridge, hinging about an axis perpendicular to
the major axis along the junction with the base.
' 25 Preferably within the tent 1, a design is.provided in
this doorway to mimic the semi-circular door shape and
create a disc. Preferably this disc incorporates a
swirl pattern which is only visualised properly when
the door 8 is open.
Figure 4 shows an alternative tent 11 having a base 12
and three canopy supporting frame members (or arches)
13. The base 12 comprises an inflatable air chamber
20 which is shown more clearly in Figure 5. In the
same way as the first embodiment, the three arches 13
meet at a common point 14 on the base 12. This allows
the arches 13 to pivot with respect to the base 12 so
CA 02494472 2005-O1-27
18
that they can fold together to collapse the structure.
As can be seen in the figure, the tent 11 may
incorporate a range of different materials to increase
interest for a child.
In one envisaged arrangement, the fabric canopy 17 is
integral with the base 12 and the arches 13 are formed
from helically bound fibre reinforced epoxy rods. The
arches 13 are sufficiently flexible to allow the
l0 structure to be folded up without first having to
remove these rods. Erection of the structure consists
of simply inflating the base 12 with a pump, the air
pressure within the base 12 being enough to unfold and
expand the structure, and then pull the fabric canopy
17 taut. It is possible to use conventional rods if
preferred, however these have the disadvantage that
they cannot be coiled up into a smaller size for
storage and therefore would need to be removed to
reduce the collapsed tent to a smaller size.
An alternative method of erection is illustrated using
Figures 5 through to 8. In Figure 5 an inflatable
chamber 20 of approximately circular form is shown in
the top of the figure. The base 22 of the tent 21 is
shown in the bottom of the figure in an inverted
configuration. To erect the tent 21, the air chamber
is inflated to create an air mattress. This is then
placed within the fabric envelope of the base 22
through the slot 28 to create the inflated base as
3o shown in Figure 6. The base 22 is then flipped over
so that it is the correct way up as shown in y~igure 7.
Around a portion of the perimeter of the base 22 are
positioned releasable fasteners 29 in the form of
Velcro~ strips. To erect the structure, the fabric
canopy 27 is pulled from its collapsed configuration
shown in Figure 7 in a direction which is
perpendicular to the plane of the arches 23 to cause
CA 02494472 2005-O1-27
19
the arches 23 to rotate about their free ends 25
located at the common points 24, and into the erected
configuration illustrated in Figure 8. The releasable
fasteners 29 are then secured to corresponding
portions of Velcro° on the fabric canopy 27 to hold it
in position.
As shown in Figure 8, the tent 21 may be provided with
a doorway 28 which can be circular, triangular (see
l0 Figure 9) or other shape.
Figure 10 shows the tent 21 from the opposite side
shown in Figure 4. Access to the valve of the air
chamber 20 is provided at 30. In this way it is
possible to simply deflate the air chamber and fold
the arches 23 together to fold up the tent 21 for
storage.
