Note: Descriptions are shown in the official language in which they were submitted.
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HAMMOCK
Field of the Invention
The present invention relates to hammocks.
Backqround of the Invention
Hammocks provide a surface suspended between upright structures (e.g.
trees, posts, etc.) on which a person may lie suspended above the ground.
Hammocks are typically constructed of a sheet of material, often flexible
(e.g. canvas,
netting, ropes, etc.) gathered at the ends and suspended from upright
structures by
ropes, straps or like means.
One drawback of traditional hammocks is known as hammock sag, whereby the
middle of the hammock sags below the ends creating a curved supporting
surface.
Such a surface is uncomfortable for an occupant as it does not follow the
natural
profile that the person's body will take when lying down. Furthermore,
traditional
hammocks provide no lumbar support or support under the knees and they are
unstable and prone to tipping.
There have been a number of attempts to provide so-called self-leveling
hammocks in an effort to ameliorate the problem. For example, Brazilian
hammocks
provide an extra wide sleeping surface so that a person may lie diagonally.
Such
hammocks require extra material and an occupant must be careful not to move
into a
non-diagonal position. USP 6,701,549, USP 645,805, USP 249,403, USP 202,814,
US 200210042951 and US 200410006820 ali describe various ways of compensating
for hammock sag. None of these has been wholly successful at providing a
comfortable, stable sleeping surface in a portable, easy to set-up hammock.
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Summary of the Invention
A hammock comprising: a bed formed from a blank of flexible fabric, the blank
defined by opposed ends and opposed sides, the ends and sides of the blank
coinciding with opposed ends and opposed side edges of the hammock
respectively,
each side of the blank tapering inwardly from the ends, each end of the blank
having a
notch having opposed edges of equal length; the opposed edges of each notch
tapering inwardly from the end towards an apex, a seam attaching the opposed
edges
of each notch to form the bed from the blank; cross-braces proximal the ends
of the
hammock, each cross-brace connected to the side edges of the hammock at
connection points opposed across the bed from one side edge to the opposite
side
edge, the fabric hanging underneath the cross-braces so that an occupant may
rest
level on the bed fully under the cross-braces; and, connecting means at each
end of
he hammock for connecting the hammock to suspending means for suspending the
hammock between upright structures.
The flexible fabric may comprise any suitable flexible material, for example;
fabrics comprising polyester, canvas, nylon, etc. Fabrics may be sheets of
closely
woven fibers or loosely woven nets or meshes. The fabric may comprise two or
more
separate fabrics linked together or, preferably, the fabric comprises a single
piece:
Preferably, the flexible fabric comprises a strong, lightweight, waterproof
fabric, for
example a polyester or polyesterlnylon blend.
The bed may be formed from a blank of the flexible fabric cut into a shape and
then attached in a manner to form the bed of the hammock. The blank is defined
by
opposed ends and opposed sides. The opposed sides each taper inwardly from the
ends towards a middle portion of the blank. Thus, the ends of the blank are
wider than
the middle portion. Each end has a notch cut out with opposed edges of the
notch
tapering inwardly from the end toward an apex. The opposed edges of each notch
preferably meet at the apex on a longitudinal axis on a centerline of the
blank.
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To form the bed from the blank, the opposed edges of each notch are attached
to form a seam. The seam may be created, for example, by sewing, gluing or
stapling
the opposed edges together. As a result, the fabric forms the bed of he
hammock in
which the ends of the blank coincide with opposed ends of the hammock and the
sides
of the blank coincide with opposed side edges of the hammock. Since the fabric
must
be folded in order to create the seams, the bed acquires a three-dimensional
structure
and the side edges meet at the ends to form a rim all around the bed.
The sides of the blank taper inwardly towards the middle portion. The opposed
sides may follow a straight line to the middle portion and then turn to become
parallel.
Alternatively, the sides may be scalloped along all or a portion of their
length provided
the sides taper inwardly from the ends to the middle portion. Preferably, the
sides are
selectively scalloped. Scalloping the sides of the blank changes the amount of
tension
experienced by various portions of the bed once the seams are formed. In this
way,
the bed can be contoured to improve support in key areas. For example, lumbar
and
knee support may be designed into the bed. Thus, altering the overall shape of
the
blank affects the way in which the hammock ultimately supports an occupant.
Forming the bed in the manner described above provides a bed upon which an
occupant may rest in a level position. If the fabric is sufficiently long, the
sides of the
blank sufficiently tapered and the notches cut sufficiently deep, the entire
height of a
person may be supported on the level bed with room at each end of the hammock
for
deep storage compartments. The weight of the occupant on the bed is suspended
and
supported along the side edges of fihe hammock in a manner similar to a
suspension
bridge. The bed can provide level support as well as lumbar and knee support
resulting in a more comfortable position for the occupant. The bed provides a
lower
center of gravity with respect to the side edges of the hammock providing
greater
stability even when the occupant moves around on the bed.
To keep the side edges of the hammock from caving-in, cross-braces may span
the hammock from one side edge to the opposed side edge. Two or more cross-
braces may be used. Preferably, two cross-braces proximal each end of the
hammock
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are used. Each cross-brace is connected to the side edges of the hammock at
connection points opposed across the bed from one side edge to the opposite
side
edge. The fabric hangs underneath the cross-braces so that an occupant may
rest
level on the bed fully under the cross-braces. The cross-braces are not
connected to
the fabric all along their length so that an occupant can rest beneath the
cross-braces.
The cross-braces function to separate the sides of the hammock and are not
needed
to support the fabric and the occupant. The cross-braces may be collapsible to
facilitate set up, take down and storage of the hammock. The cross-braces may
comprise any suitably rigid material, for example, wood, metal (e.g. aluminum
or
magnesium alloy), plastic, plastic composites, etc.
The sides of the blank or the side edges of the hammock may be reinforced to
provide a stiffer rim for the hammock. The rim should still be flexible, but
making the
sides or side edges stiffer provides for stronger support for the occupant's
weight and
stronger connection points for the cross-braces. Reinforcement may be
accomplished, for example, by using additional, stiffer material attached to
the sides or
side edges, or by attaching ropes, cables, wires, rods, etc, to the sides or
side edges:
Attachment may be conveniently accomplished by sewing, stapling, gluing, etc:
Preferably, reinforcement comprises additional material (e.g. seat belt
material) sewed
onto or into the sides of the blank prior to forming the bed. Preferably,
reinforcement
is curved along the side edges between the cross-braces.
Connecting means at each end of the hammock are present for connecting the
hammock to suspending means. Suspending means are used to suspend the
hammock between upright structures. Preferably, the connecting means are
located
at the ends of the hammock where the side edges meet. These points may be
further
reinforced. Connecting means may be, for example, loops, rings, buckles or
hooks
attached directly to the hammock or to straps, ropes, cables or the like
attached to the
hammock. In a preferred embodiment, an excess length of strap is sewn onto the
side
edges of the hammock all around the rim to reinforce the side edges; with the
excess
length forming loops at each end of the hammock. Hooks, buckles or rings may
be
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further connected to the loops. The hammock may be suspended between upright
structures by means of suspending means, for example ropes, straps, cables and
the
like. One end of the suspending means is connected to the connecting means
while
the other end is connected to the upright structure. Upright structures may
be, for
5 example, trees, posts, walls with hooks, etc. Buckles, knots, hooks or other
securing
means may be used to secure the suspending means to the upright structure
andlor
connecting means.
A unique arrangement for connecting the hammock to the suspending means is
also disclosed herein. In order to facilitate putting up and taking down the
hammock, a
quick-change connection system is desirable. To this end, a cargo hook having
a
hook portion and a ring portion is provided. The cargo hook acts as an
intermediate
connecting structure between the connecting means of the hammock and the
suspending means. In this arrangement, the connecting means is a loop of
flexible
material and the suspending means is a rope, strap or cable having a loop at
one end.
The loops of the connecting means and the suspending means may be successively
threaded through the ring portion of the cargo hook and looped over the hook
portion
to form quick, secure and easily reversed connections to the cargo hook.
Preferably, connection of the hammock's connection means to the cargo hook
is performed last so that the hammock may be disconnected from the cargo hook
without having to disconnect the suspending means from the cargo hook. In this
way;
the hook is less likely to get lost as it can be stored while remaining
attached to the
suspending means. Additionally, the hammock can then be quickly folded and
stored
without the hook since the hook may damage the fabric of the hammock if it is
stored
together with the hammock. Also, the suspending means with the hook can be
removed and/or replaced without affecting the hammock.
A special securing means for securing the suspending means to the upright
structure may be used. With most hammocks, the suspending means is a rope,
cable
or strap that is tied around the upright structure (e.g. a tree, post, etc.)
and knotted in
place. Such an arrangement is difficult to do and undo and is not amenable to
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adjustment once secured. In many instances, it is desirable to be able to
adjust the
length of the suspending means without having to undo it from the upright
structure.
To this end, the suspending means is preferably a flat strap with a cam buckle
that
permits adjustment of the strap without removing the strap from the upright
structure.
In operation the strap is normally wrapped around the upright structure and an
end of
the strap fed through an opening in the housing of the cam buckle. Normally;
the end
of the strap that is fed through is the one closest to where the buckle will
be so that
time is not wasted feeding great lengths of strap through the buckle. However,
when a
cargo hook is connected to one of the strap, only one end of the strap is
free, unless
the cargo hook is removed, which is also a waste of time.
Since there is great variability in the possible distances between upright
structures, great lengths of strap are required to ensure that the hammock can
be set
up in many different places. Thus, a quick and simple way of introducing the
buckle to
or removing the buckle from any location along the strap is greatly desired.
To
facilitate this, the cam buckle is advantageously provided with a narrow slot
in the
housing so that the strap can be fed edgewise into the opening of the housing.
In this
way, the cam buckle can be quickly and easily introduced on and/or removed
from the
strap at any location along the strap, greatly decreasing the time required to
sef up
and to take down the hammock.
The hammock of the present invention may also be provided with a bug screen
and/or a tent. The bug screen may take the form of a mesh tube open at both
ends
that slides over and surrounds the hammock. The bug screen may also comprise
additional sections that overlap with the mesh tube and close off one or both
ends in
order to completely enclose the hammock. The bug screen may be attached to the
hammock or the tent, for example with VeIcroT"", snaps, ties, etc., to help
keep the bug
screen in place once it is set up.
The tent may comprise several overlapping sections that fit around the
hammock. The bug screen and the tent may be used in combination and a single
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supporting system supports the bug screen and the tent, whether they are used
separately of together.
The bug screen and the tent are supported by a supporting system that
comprises two or more side supports, one or more ridge supports and two or
more
suspension supports. Preferably two side supports, one for each side, one
ridge
support and two suspension supports, one for each end, are used. The supports
are
preferably straps. One end of each side support, one end of the ridge support
and one
end of one of the suspension supports meet and are connected at a nexus
located at
one end of the supporting system. A similar nexus is present at the other end
of the
support system. When the support are straps, the nexus may be a ring structure
to
which the straps are attached. The suspension supports are secured to upright
structures to keep the support system off the ground and in position to
support the bug
screen andlor tent around the hammock.
The side andlor ridge supports may be adjustable to increase or decrease
tension on the bug screen andlor tent that they support. This facilitates
entering and
exiting the hammock when the tent is used since the tent is preferably
tensioned to
provide more space when the hammock is occupied, but is preferably not
tensioned
when the occupant is entering and exiting the hammock so that the tent does
not get
in the way. The side and/or ridge supports may further have one or more
pockets
attached thereto for storing items.
The tube-shaped bug screen may be fitted over the side and ridge supports like
a sock fit over a foot. The side and ridge supports keep fabric of the bug
screen from
collapsing in on the occupant of the hammock. The tent may be used together
with or
separately from the bug screen. When used with the bug screen, the tent fits
over the
bug screen so that the bug screen is inside the tent.
The tent preferably comprises several separate overlapping covers, e.g. a foot
cover, a head cover, a ridge vent cover and one or more mesh vents. The foot
and
head covers are generally tube-shaped and fit over the supporting system and
around
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the hammock. The foot and head covers meet and overlap proximal the middle of
the
hammock thereby completely surrounding the hammock. The foot andlor head
covers
may have one or more vents. Preferably, there is both a top and a bottom vent.
The
ridge vent cover preferably fits over the foot and head covers and is able to
cover or
be removed from the top event when desired. The covers may be connected
together,
for example, by means of snaps, ties or VeIcroT"".
A door is provided in the tent to permit an occupant to enter and exit the
hammock. The door advantageously arises from the use of separate foot and head
covers. The foot andlor the head cover may be provided with a flap that may be
moved to open a portal in a side of the tent proximal where the foot and head
covers
overlap. Preferably, the flap is equipped with means, for example, snaps, ties
or
VeIcroT"", for securing the flap in a closed position.
Advantageously, the tent is adaptable to be a stretcher, particularly if the
ridge
support is sufficiently rigid, for example if the ridge support is a pole.
The hammock and its components together with the bug screen, tent and
supporting system may be sold as a kit. Instructions for set up and take down
may
accompany the kit. The kit may include a rain fly.
A hammock of the present invention offers a number of advantages over prior
art hammocks. The hammock is more portable, being easier to put up and take
down
and lighter in weight. It is more stable permitting an occupant to move around
without
fear of tipping and permitting an occupant to sleep on his/her side. The
hammock is
more comfortable as it provides a I~vei surface, with the added benefit of
lumbar and
knee support. The deep storage spaces at the ends of the hammock permit an
occupant to store gear in the hammock off the ground, and out of the rain if a
tent
embodiment is used. The tent embodiment provides a quick, light weight way of
getting out of the rain. Interior ventilation adjustment permits ventilation
without having
to exit the hammock. That the tent and bug screen are separate structures from
each
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other and the hammock permits the use of the hammock with or without the tent
or
bug screen, and permits the owner of the hammock to upgrade at a later date.
Further features of the invention will be described or will become apparent in
the course of the following detailed description.
Brief Description of the Drawings
In order that the invention may be more clearly understood, embodiments
thereof will now be described in detail by way of example, with reference to
the
accompanying drawings, in which:
Fig. 1 is a side view of a hammock of the present invention suspended between
two trees;
Fig. 2 is a side schematic view of the hammock of Fig. 1 having a person lying
therein;
Fig. 3A is a schematic view of the hammock of Fig. 1 showing lines of support;
Fig. 3B is a schematic view of a prior art hammock showing lines of support;
Fig. 4A is a plan view of a blank for forming a bed of the hammock depicted in
Fig. 1;
Fig. 4B is a side schematic view of the blank of Fig. 4A after being sewn
along
opposed edges of each notch;
Fig. 5 is a side view of the hammock of Fig. 1 in combination with a tent
having
an open door;
Fig. 6 is a side view of the hammock of Fig. 1 in combination with a tent
having
an closed door;
Fig. 7 is a side schematic view of an alternate embodiment of a tent for use
with
a hammock of Fig. 1;
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Fig. 8 is a plan view of blanks for forming a foot cover, a head cover, a
ridge
vent cover and a mesh vent for the tent depicted in Fig. T;
Fig. 9A is a perspective view of a cargo hook having a suspending strap
threaded therethrough;
5 Fig. 9B is an alternate perspective view of the cargo hook of Fig. 9A with
the
suspending strap in a suspending orientation;
Fig. 10A is a perspective view of the cargo hook of Fig. 9B with a hammock's
connecting loop threaded therethrough;
Fig. 10B depicts the cargo hook of Fig. 10A with the connecting loop hooked
10 over the cargo hook;
Fig. 10C is the cargo hook of Fig. 10B with the suspending strap and the
connecting loop in their fully supporting positions;
Fig. 11 is a perspective view of a cam buckle of the present invention;
Fig. 12A is a perspective view of a suspending strap being inserted into the
cam
buckle of Fig. 11; and,
Fig 12B depicts the cam buckle in Fig. 12A with the suspending strap threaded
therein and surrounding a post.
Description of Preferred Embodiments
Referring to Fig. 1, hammock 1 of the present invention is suspended off the
ground between two trees 2. Hammock 1 comprises level bed 5 made of a durable
waterproof polyester fabric. Side edges 6,7 of the hammock are reinforced with
seat
belt material to provide a stiffer yet flexible support for the fabric
including bed 5.
Hammock 1 is shown with side strap 51 having pocket 5~.
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Referring to Fig. 2, a side schematic view of hammock 1 has a person 41 lying
therein. Bed 5 of hammock 1 provides excellent lumbar support at 8 and knee
support
at 9 while permitting person 41 to lie in a generally level position below
cross-braces
(not shown) connected to side edge 6 at points 13,14. Storage compartments
10,11 in
bed 5 are located at the head end and foot end of the hammock.
Fig. 3 compares hammock 1 (Fig. 3A) to a prior art hammock 100 (Fig. 3B). In
hammock 1, fabric of bed 5 is supported from side edges 6,7 and is connected
to
cross-braces 17,18 only at ends 21,22,23,24 of the cross-braces. The fabric
thus lies
underneath cross-braces 17,18 and a person can lie flat under the cross-
braces. In
contrast, fabric of bed 105 of prior art hammock 100 is attached all along
cross-braces
117,118. Therefore, a person lying in hammock 100 cannot lie flat and must
assume a
V-shape. Lines of force are shown in broken lines. In hammock 1, the lines of
force
on bed 5 are from side to side; thus, bed 5 is supported from side edges 6,7,
not
cross-braces 17,18. In contrast, prior art hammock 100 has lines of force from
end to
end; thus, bed 105 is supported from cross-braces 117,118. Cross-braces 17,18
function to separate side edges 6,7 and do not support bed 5. Therefore, cross-
braces 17,18 may be collapsible having breakdown joints 25,26 to facilitate
packing
and storage of the hammock.
Referring to Fig. 4, the hammock of the present invention is can be further
distinguished from prior art hammocks, including other so-called self-leveling
hammocks by virtue of fihe way in which the bed is made from a blank of
fabric. Fig:
4A depicts a blank 30 of polyester fabric having opposed ends 31,32 and
opposed
sides 33,34. Each side 33,34 of blank 30 tapers inwardly from ends 31,32. Each
end
31,32 has a notch having opposed edges 35,36 and 37,38. Edge 35 is equal in
length
to edge 36. Edge 37 is equal in length to edge 38. Edges 35,36 are not equal
in
length to edges 37,38. The opposed edges of each notch taper inwardly from the
ends towards apexes 39,40. Sides 33,34 are scalloped. Such scalloping provides
the
lumbar and knee support once seams are sewn attaching edge 35 to edge 36 and
edge 37 to edge 38 to form the bed from blank 30. Ends 31,32 at 45 are not
sewn
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together. Fig. 4A depicts a side view of bed 5 once seams 43,44 are sewn.
Sides
33,34 are reinforced by sewing seat belt material along the sides. One
continuous
length of seat belt material sewed together at its ends is used to provide
stiffened side
edges of the hammock. Since the ends at 45 are not sewn together, loops at
each
end are formed bounded by the seat belt material and the seams. Such loops are
used to connect the hammock to suspending means.
Referring to Figs. 5 and 6, a hammock is shown in combination with a tent 60.
Tent 60 completely surrounds the hammock and the tent has flap 69 that serves
as a
door. The door may be open {Fig. 5) or closed (Fig. 6).
Referring to Fig. 7, in an alternate embodiment, tent 80 comprises overlapping
sections. Generally tubular toot cover 81 and generally tubular head cover 82
that
surround the hammock (not shown) overlap in region 88. Foot cover 81 comprises
bottom vent 86 and top vent 87. Bottom vent 86 is covered by a mesh vent
cover.
Top vent 87 is covered by ridge vent cover 83. Foot cover 81, head cover 82
and ridge
vent cover 83 are held together by VeIcroT"" 85. Generally tubular bug screen
70 open
at both ends surrounds the hammock and is between the hammock and tent 80.
Fig. 8 depicts blanks for forming the various parts of the tent depicted in
Fig. 7.
The foot cover is formed from foot cover blank 301 by finishing edges 302a and
302b
on a sewing machine and sewing edges 310 and 311 together so that blank 301
folds
along fold line 315. Edges 303 and 304 are sewed together and edges 305 and
306
are sewed together. Edges 307a and 307b form one edge when edges 303 and 304
are sewn together and edges 308a and 308b form one edge when edges 305 and 306
are sewn together. Edges 307a,b and 308a,b are sewed to edges 352 and 353,
respectively, of mesh vent cover 351. The mesh vent cover covers the bottom
vent
which is formed by an airspace between edges 307a,b and 308a,b. An airspace
between edges 302a and 302b provides for the top vent, which is located under
the
ridge vent cover when the tent is set up.
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Still referring to Fig. 8, the head cover is formed from head cover blank 321
by
sewing edge 322 to edge 323 and edge 324 to 325. Sewing edge 322 to edge 323
creates a single edge from edges 326a and 326b, and sewing edge 324 to edge
325
creates a single edge from edges 327a and 327b. Single edge 326a,b is sewed to
single edge 327a,b. Edge 328 is sewed to edge 329 so that head cover blank 321
is
folded along fold line 335. Edges 330a and 330b are finished on a sewing
machine.
Still referring to Fig. 8, the ridge vent cover is formed from two ridge vent
cover
blanks 341 and 342 by sewing edge 343 to edge 344. All other edges are
finished on a
sewing machine.
Figs. 9 and 10 illustrate how the hammock of the present invention may be
connected to suspending means. As seen in Fig. 9A and 9B, flat suspending
strap 99
having a loop in one end is inserted through ring portion 92 of cargo hook 90
and then
looped around hook portion 91 of cargo hook 90. Cargo hook 90 is then nested
within
the loop of suspending strap 99 to provide further access to ring portion 92
(see Fig.
9B). As seen in Figs. 10A-10C, loop 94 formed by side edges 6,7 of the hammock
is
then inserted through ring portion 92 of cargo hook 90 and looped over hook
portion
91. The hammock is now connected to suspending strap 99 by means of cargo hook
90 as depicted in Fig. 10C. Since loop 94 was last to be inserted, it is first
to be
removed, thus cargo hook 90 can remain connected to suspending strap 99 for
storage when the hammock is taken down.
Figs. 11-12 depict a way in which suspending strap 99 is secured to an upright
strucfiure. Cam buckle 200 is provided having slot 205 through which an edge
of
suspending strap 99 may be inserted in order to insert the strap into aperture
210 of
cam buckle 200. Thus, strap 99 can be wrapped around upright structure 220 at
the
appropriate length and quickly inserted into cam buckle 200 without having to
feed
strap 99 through aperture 210 all the way from an end of the strap. Unwrapping
suspension strap 99 from upright structure 220 is just as easily done in
reverse.
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Other advantages which are inherent to the structure are obvious to one
skilled
in the art. The embodiments are described herein illustratively and are not
meant to
limit the scope of the invention as claimed. Variations of the foregoing
embodiments
will be evident to a person of ordinary skill and are intended by the inventor
to be
encompassed by the following claims.
