[0001] The present invention relates to a tent frame comprising a hub from which extends
a plurality of limbs, respective ends of some of which are secured to the hub by way
of respective pivots, constituting a first set of pivots, having respective pivot
axes which are generally parallel to one another.
[0002] One such previously proposed tent frame is described and illustrated in
EP 1445400 A1. In the construction of tent frame described therein, the said first set of pivots
are located on a first part of the hub, and a plurality of limbs extend from a second
part of the hub and are secured to that part of the hub by way of respective pivots,
constituting a second set of pivots, having respective pivot axes which are also generally
parallel to one another. The first and second parts of the hub are pivoted relative
to one another, and sheet material is attached to the limbs of the tent frame so that
when the two parts of the hub are pivoted to bring the axes of the said second set
of pivots parallel to those of the said first set, the sheet material is opened out
to form a canopy supported by the limbs of the frame, and the pivot axes of the first
set of pivots are substantially parallel to those of the second.
[0003] A disadvantage of this construction is the strength required to pivot the two parts
of the hub relative to one another in this fashion to erect the tent. For this purpose
respective recesses are formed in the two parts of the hub, into which recesses are
inserted the ends of respective levers to enable considerable force to be exerted
on the two parts of the hub to bring them together in the foregoing fashion. A latch
pivoted to a formation on one of the hub parts is then swung round to latch onto a
corresponding formation on the other part of the hub to secure the hub parts together
in such an erect condition of the frame, whereupon the levers are removed. Such a
construction is therefore relatively expensive and complex, and requires a relatively
awkward assembly procedure.
[0004] The present invention seeks to provide a remedy.
[0005] Accordingly, a first aspect of the present invention is directed to a tent frame
having the construction set out in the opening paragraph of the present specification,
characterised in that respective ends of at least two of the said plurality of limbs
are secured to the hub by way of respective pivots, constituting a second set of pivots,
enabling the said at least two of the said plurality of limbs to be pivoted about
respective axes which are transverse, or have a component which is transverse, of
the pivot axes of the said first set of pivots whilst the frame is unfolded into an
erect condition and whilst it is folded for stowage, the pivots of the first and second
set of pivots being fixed in position relative to one another even when the limbs
are pivoted about their respective pivots.
[0006] This enables a relatively simple and inexpensive construction of tent frame to be
made, in such a fashion that its erection is relatively simple.
[0007] The said first set of pivots may be spaced apart around the hub.
[0008] This provides an even distribution of the support for sheet material when such material
is attached to the tent frame.
[0009] The said second set of pivots may be located together on one side of the hub.
[0010] This again facilitates a relatively easy erection of the tent frame.
[0011] The said second set of pivots may have fixed pivot axes which are set at an angle
relative to one another so that the associated limbs are splayed when the tent frame
is in an erect condition.
[0012] The said second set of pivots may have respective pivot axes which are orthogonal
to those of the first set. This results in a relatively low force being required initially
to open out the frame.
[0013] The pivots of the said first set of pivots may comprise respective pins extending
through respective inner ends of the associated limbs.
[0014] This provides a relatively inexpensive way of manufacturing those pivots.
[0015] The pivots of the said second set of pivots may comprise axle portions of the hub
embraced by generally circular portions on the sides of respective end portions of
the associated limbs.
[0016] Alternatively the hub may be provided with respective cams for at least two limbs
attached to the hub by way of universal pivots constituting or being included in the
said second set of pivots.
[0017] The cams may be such as to generate a movement of the said at least two limbs when
the frame is unfolded, which movement is such that the limbs splay away from one another
as the latter are rotated about their respective pivots through a first part of such
movement at a greater rate than in a second part of that movement.
[0018] This increases the extent to which the taughtness of sheet material is spread evenly
across the dome it is beginning to form when attached to the frame.
[0019] The tent frame may comprise a further limb arranged centrally in relation to the
other limbs of the tent frame, which further limb is fixed relative to the hub.
[0020] Such a fixed central limb may be in the same position relative to the hub for both
the erect condition of the tent frame and the collapsed condition of the tent frame.
[0021] The said second set of pivots may be arranged between two pivots of the said first
set of pivots.
[0022] Such a construction lends itself more readily to erection of the tent frame.
[0023] With such a construction, the other pivots of the said second set of pivots, viewed
in a direction perpendicular to an imaginary line joining the midpoints of the said
two pivots of the said first set of pivots, are within those midpoints.
[0024] This again affords an even distribution of support for sheet material when it is
attached to the tent frame.
[0025] The said at least two limbs may be retained in their splayed condition by one or
more braces, for example by a rod or bar which may be removeably attached between
and to each of those limbs.
[0026] According to a second aspect of the present invention, there is provided a tent frame
comprising a hub from which extends a plurality of limbs, respective ends of which
are secured to the hub by way of respective pivots, so that each leg is pivotable
between a stow position and an extended position it adopts when the frame is in use,
characterised in that at least one of the limbs can be retained in its extended position
by means of interengaging parts respectively mounted on the hub and the hub end of
the said at least one of the limbs, at least one of those interengaging parts being
slidable between a first position, in which it accommodates movement of the other
of those parts whilst the said at least one of the limbs is brought into its extended
position, and a second position in which it engages the said other of those parts
to retain the said at least one of the limbs in its extended position.
[0027] Such a construction enables the speedy erection and collapse of the tent frame.
[0028] The said at least one of the interengaging parts may be spring-loaded towards the
said second position, so that upon movement of the said at least one of the limbs
towards its extended position, the said one of those interengaging parts is slid by
the said other of those interengaging parts to its said first position, and so that
upon the said at least one of the limbs reaching its extended position, the said one
of those interengaging parts snaps back to its second position so that those two parts
can engage one another in such a manner as to retain the limb in its extended position.
[0029] This further facilitates speedy erection and collapse of the tent frame.
[0030] According to a third aspect of the present invention, there is provided a tent frame
comprising a hub from which extends a plurality of limbs, respective ends of which
are secured to the hub by way of respective pivots, so that each limb is pivotable
between a stow position and an extended position it adopts when the frame is in use,
in which at least one of the limbs is provided with a slider coupled to the said at
least one of the limbs in such a manner as to be slidable therealong away from and
towards the hub, there being two cross-members pivotally connected to the slider and
extending therefrom to respective pivots on respective ones of the limbs which are
on opposite respective sides of the said at least one of the limbs, whereby when the
limbs are moved to their extended positions, the slider can slide along the limb on
which it is provided away from the hub so that the cross-members retain the said respective
ones of the limbs at a splay angle relative to the said at least one of the limbs.
[0031] Such a construction ensures a desired splay angle between the said at least one of
the limbs and those two limbs on opposite sides thereof, and as a result ensures a
desired degree of tensioning of any tent fabric supported by the frame.
[0032] The slider may be retained in the position it adopts when the limbs are in their
extended positions by means of a clip, pin, latch or over-centre mechanism.
[0033] The present invention extends to a tent comprising a tent frame made in accordance
with the present invention together with sheet material supported by the frame.
[0034] The construction of the tent frame is such that such sheet material can remain on
the frame during stowage, during its use as a tent, and whilst the tent is being erected
and whilst the tent is being collapsed. Thus the sheet material never has to be removed
from the frame. The unfolding of the frame results in the sheet material being spread
out into a canopy supported by the frame during use, and folding up of the frame results
in the sheet material also being folded up for stowage. This therefore provides for
efficient and speedy changeover from the folded condition of the tent to the unfolded
condition, and vice versa.
[0035] Examples of tent frames made in accordance with the present invention will now be
described in greater detail with reference to the accompanying drawings, in which:
Figure 1 shows a perspective view of the underside of a hub and limb portions of a
tent frame embodying the present invention;
Figure 2 shows a perspective view from above of the tent frame shown in Figure 1,
together with part of sheet material supported by the frame;
Figures 3a to 3e show respectively an underneath view, a perspective view from above
and to one side, a top view, an end view and a side view of the tent frame shown in
Figures 1 and 2 in a condition just after unfolding of the frame has commenced;
Figures 4a to 4e, 5a to 5e, 6a to 6e and 7a to 7e show views corresponding to Figures
3a to 3e for successive conditions of the frame as it is unfolded;
Figure 8 is a diagram illustrating the movement of limbs of the frame shown in Figures
1 to 7e between a folded condition of the frame and an unfolded condition of the frame;
Figures 9 to 16 show views which correspond to those of Figures 1 to 8, of a second
embodiment of the present invention;
Figures 17 to 23 show views which correspond to those of Figures 1 to 7, of a third
embodiment of the present invention; and
Figures 24 to 27 show respective perspective views of successive stages in the collapsing
of the tent frame shown in Figures 17 to 23.
[0036] The tent frame 10 shown in Figures 1 and 2 comprises a hub 12 from which extend a
plurality of limbs 14 and 15. Only portions of each limb 14,15 which are closer to
the hub 12 are shown in Figures 1 and 2. A first set of these limbs 14 are connected
to the hub 12 by way of respective pivots 16. Each pivot 16 comprises a pin 18 which
has its opposite ends fixed to respective flanges 20 and 22 of the hub 12 so that
each pin extends from one flange 20 to the other flange 22. An inner end of the associated
limb 14 is provided with the through-hole (not shown) which extends through it and
through which extends the associated pin 18. This enables the limb 14 to swing about
its associated pivot 16. Furthermore, from this described construction it will be
appreciated that the pivots 16 constitute a first set of pivots of the frame 10 the
pivot axes of which are parallel to one another.
[0037] Viewing the hub 12 along a median bisector thereof, the set of pivots 16 comprises
two outermost pivots of the set, the other two pivots of which appear to be within
those outer pivots when viewed in that direction.
[0038] A second set of limbs of the frame 10 constituted by the limbs 15 are attached to
the hub 12 by way of respective pivots 24 constituting a second set of pivots located
between the outermost pivots of the set of pivots 16.
[0039] Each pivot 24 comprises a bar (not shown) of the hub 12 which is of circular cross-section
and which extends between two portions of the hub 12 in a direction which is orthogonal
to the pins 18. A connector 26 of each pivot 24 comprises a tubular portion 28 which
receives one end of its associated limb 15 in such a fashion as to be fixed relative
thereto, with a portion 30 of the limb 15 extending beyond the tubular portion 28
within the hub 12 when the frame is in the extended condition shown in Figures 1 and
2. Each connector 26 further comprises a ring portion 32 which surrounds its associated
bar of the hub 12 so as to be rotatable thereabout.
[0040] As shown in Figures 1 and 2, this particular illustrated frame 10 has three limbs
15 with three respective pivots 24. The bar of the central one of these pivots 24
is generally parallel to an imaginary line connecting the outermost pivots 16 of the
first set of pivots. The bar of each of the other pivots 24 is on a slight slant relative
to the central bar so that the limbs 15 are splayed apart from one another in a direction
away from the hub 12 when the frame 10 is in the extended condition shown in Figures
1 and 2.
[0041] Figure 2 also shows a portion of sheet material 34 which is attached to the limbs
14 and 15.
[0042] Figures 3 to 7 show the frame 10 in successive stages of being unfolded from a stowage
condition shown in Figure 3 to an unfolded condition shown in Figure 7 in which the
combination of the frame 10 and the sheet material 34 constitute a tent, with the
limbs 14 and 15 curving in a manner not shown so that they extend outwardly from the
hub 12 and then downwardly towards the ground with the sheet material 34 adopting
the shape of a dome to constitute a cover of the tent.
[0043] Thus it will be seen that as the frame 10 is unfolded, each limb 14 and 15 swings
about its respective pivot relative to the hub 12. As the limbs 14 are fanned out
from a position in which they are generally parallel to one another in the folded
stowaway condition to a position in which they are spread outwardly from the hub 12
in a star formation, the limbs 15 rotate about their respective pivots 26 between
a position in which they are generally parallel to the limbs 14, about pivot axes
which are at right angles to those of the set of limbs 14, to a position in which
those portions of all the limbs 14 and 15 which are close to the hub 12 are in the
same general imaginary plane as one another. Furthermore, all the limbs fan out from
the hub 12 and from one another, the spacing between the limbs 15 which are now splayed
relative to one being slightly less than the spacing between the limbs 14. These limbs
15 support an entrance (not shown) to the tent.
[0044] As the limbs 14 and 15 of the frame 10 are unfolded, so the sheet material 34 which
is attached to these limbs is also spread out into a dome formation. It therefore
remains attached to the limbs 14 and 15 throughout the unfolding procedure.
[0045] After use, the tent may be folded up in stages also illustrated in Figures 3 to 7,
but in reverse order, with the sheet material 34 being folded up as a result of the
limbs 14 and 15 being folded together, so that the sheet material remains attached
to the limbs 14 and 15 in the folded up stowaway position ready for the next unfolding
of the tent when it is next erected.
[0046] It will be appreciated that when the tent is in its unfolded, erected condition,
what is now the upper side 36 of the hub 12 now has sheet material 34 (not shown in
Figure 1) taught just below it and against it with the ends 30 of the limbs 15 remaining
recessed in the hub 12.
[0047] The limbs 15 may be retained in their splayed condition by means of one or more braces,
comprising one or more cross-bars or rods (not shown) extending between and attached
to one or more of the limbs 15.
[0048] The paths 38 of respective points on the three limbs 15 outwardly of the hub 12 as
the limbs are unfolded are shown diagrammatically in Figure 5, so that those points
are generally adjacent to one another at a first end 40 of each path 38, when the
frame 10 is in the folded condition, and travel through a near semicircular path so
as to be spaced apart from one another, at the other ends 42 of the paths, in the
unfolded condition with the limbs 15 splayed apart from one another.
[0049] The embodiment of the present invention shown in Figures 9 to 16 is substantially
the same the embodiment shown in Figures 1 to 8, except in the following respects.
[0050] Firstly, the flanges 20 and 22 are reduced at portions of the hub 12 between the
pivots 16. Secondly, a fifth limb 14a is rigidly fixed to the hub 12, and extends
along a median bisector of the hub 12. Thirdly, the two outer pivots of the set of
pivots 24 are constituted by ball and socket joints, or universal joints, to give
the associated limb a greater degree of freedom in its ability to be pivoted about
the pivot 24. Fourthly, portions 60 of the hub 12 define respective guide cams for
the outer pivots 24 such that the movement of points of the set of limbs 15 which
are located outwardly of the hub 12 follow the paths represented diagrammatically
in Figure 16. It will be seen from this Figure that the limbs 15 are splayed apart
more rapidly during the first portion of the paths 38 near to the ends 40 thereof
than they are during the remainder of those paths 38. This reduces the rate of splaying
as the limbs 15 are swung outwardly once the tent is in a relatively unfolded condition
to increase the extent to which the taughtness of the sheet material 34 is spread
evenly across the dome it is beginning to form.
[0051] The embodiment of the present invention shown in Figures 17 to 27 is substantially
the same the embodiment shown in Figures 9 to 16, except in the following respects.
[0052] Firstly, the hub end of the centre of the three legs or limbs 15 is reinforced by
a connector 50 which has a tubular portion 52 which receives a hub end of the centre
leg 15, and trunnions 54 through which a cylindrical bar (not visible in the Figures)
extends from one support block portion 56 of the hub 12 on one side of the connector
52 to another support block portion 56 of the hub 12 on the other side of the connector
52. This construction provides a pivot between the centre leg or limb 15 and the hub
12. A centre support 58 of the hub 12 through which the bar passes is also provided
to add strength to the pivot construction.
[0053] On the upper side of the connector 50 there is provided a hollow arched portion 60
which is open in the direction of the hub 12 and which can be seen more clearly in
Figures 18 and 27. This portion 60 has transverse serrations or teeth (not shown)
on the interior of its upper arcuate wall. It forms the first part of a snap-action
locking device.
[0054] The second part of the snap-action locking device is provided by a slidable block
62 secured slidably on the hub 12. The block 62 is formed with an arcuate recess 64
which accommodates a part of the arched portion 60, and a forwardly protruding tongue
portion 66 which is visible in Figures 25, 26 and 27. The tongue portion 66 has an
upper curved surface 68 as viewed in cross-section, and this upper curved surface
68 has transverse serrations or teeth and has the same radius of curvature as that
of the interior of the arched portion 60. The slidable block 62 is slidable towards
and away from the front edge of the block 12 and is urged by a spring (not shown)
into a forward position further from the rear leg or limb 14a.
[0055] Further transverse serrations or teeth (not shown) are also provided on the underside
of the tongue portion 66 to engage with transverse serrations or teeth (not shown)
on the block 12 when the tent frame is in use.
[0056] When the centre leg or limb 15 is pivoted relative to the hub into its extended position,
the arcuate portion 60 of the connector 50 engages the slidable block 62 of the hub
12 and urges it rearwardly. When the centre leg 15 is in its fully extended position,
the arcuate portion 60 of the connector 50 clears the upper forward edge of the tongue
66 so that the slidable block 62 snaps forward into a position in which the tongue
66 extends within the hollow arcuate portion 60 of the connector 50. Only a very slight
downward movement of the centre leg or limb 15 will now be allowed before the teeth
of the tongue 66 and the teeth of the arcuate portion 60 of the connector 50 interengage
to prevent further such downward movement.
[0057] To collapse the tent from the erect condition of the tent frame as shown in Figure
24, the centre leg or limb 15 is urged upwardly to disengage the serrated teeth of
the arcuate portion 60 of the connector 50 from those of the tongue 66 so that the
slidable block 62 can be slid rearwardly as shown in Figure 25. The centre leg or
limb 15 is now free to be lowered to the collapsed or stow position as shown in Figures
26 and 27.
[0058] Secondly, the centre leg or limb 15 is provided with a flat 70 running along its
length. A slider 72 shown for example in Figure 21a surrounds the centre leg 15 and
is provided with a corresponding flat (not shown) which engages the flat 70 to prevent
rotation of the slider 72 around the centre leg 15. However, the slider 72 is free
to slide along the centre leg 15 towards and away from the hub as shown for example
in Figures 21a, 22a and 23a. Respective cross-members 74 and 76 are pivotally attached
at respective ends thereof to the slider 72 by respective pivots 78 and 80 and are
pivotally attached at their other ends to respective outer ends of the outer two legs
or limbs 15 by respective pivots 82 and 84. The pivots 78, 80, 82 and 84 are universal
joints to facilitate the degree of freedom of movement required. A latch (not shown)
may hold the slider 72 at its position in which the two cross-members 74 and 76 are
substantially collinear. In this way they retain the outer legs or limbs 15 at a desired
angle relative to the centre leg 15, and the sheet material or fabric 34 of the tent
is maintained at a desired tension.
[0059] With such a construction, as the frame is changed from its stow condition to its
erect condition, the centre leg or limb 15 is raised, and the attachment of the sheet
material or fabric 34 of the tent to the frame causes the outer legs or limbs to raise
accordingly. Once the centre leg has been snapped into its fully extended position,
the cross-members can be brought into alignment with one another by sliding the slider
72 fully to its latched position, so the the sheet material or fabric 34 of the tent
is fully stretched, and the canopy (not shown) over the tent entrance is properly
shaped.
[0060] As with the previously described embodiments, the legs or limbs 15 of the second
set of legs or limbs of the tent frame are shorter than those legs or limbs 14 of
the first set, although this is not evident from the Figures because they only show
parts of the legs or limbs 14. With such a construction, the fabric 34 of the tent
forms a canopy over an entrance (not shown) of the tent when the frame is in its erected
condition.
[0061] Numerous variations and modifications may occur to the reader without taking the
resulting construction outside the scope of the present invention. For example, there
may be only two limbs 15 instead of the three illustrated in the Figures. Furthermore,
the limbs 15 do not necessarily curve when the tent is in the unfolded, erect condition.
There may be more or fewer limbs 14 than those illustrated.
1. A tent frame (10) comprising a hub (12) from which extends a plurality of limbs (14,15),
respective ends of some of which are secured to the hub (12) by way of respective
pivots (16), constituting a first set of pivots, having respective pivot axes which
are parallel to one another, characterised in that respective ends of at least two (15) of the said plurality of limbs (14, 15) are
secured to the hub (12) by way of respective pivots (24), constituting a second set
of pivots, enabling the said at least two (15) of the said plurality of limbs (14,
15) to be pivoted about respective axes which are transverse, or have a component
which is transverse, of the pivot axes of the said first set of pivots (16) whilst
the frame (10) is unfolded into an erect condition and whilst it is folded for stowage,
the pivots (16, 24) of the first and second set of pivots being fixed in position
relative to one another even when the limbs (14, 15) are pivoted about their respective
pivots (16, 24).
2. A tent frame (10) according to claim 1, characterised in that the pivots (24) of the said second set of pivots are located together on one side
of the hub (12).
3. A tent frame (10) according to claim 1 or claim 2, characterised in that the pivots (24) of the said second set of pivots have fixed pivot axes which are
set at an angle relative to one another so that the associated limbs (15) are splayed
when the tent frame (10) is in an erect condition.
4. A tent frame (10) according to claim 1 or claim 2, characterised in that the hub (12) is provided with respective cams (60) for at least two limbs (15) attached
to the hub (12) by way of universal pivots constituting or being included in the said
second set of pivots (24).
5. A tent frame (10) according to claim 4, characterised in that the cams (60) are such as to generate a movement of the said at least two limbs (15)
when the frame (10) is unfolded, which movement is such that the limbs (15) splay
away from one another as the latter are rotated about their respective pivots (24)
through a first part of such movement at a greater rate than in a second part of that
movement.
6. A tent frame (10) according to any preceding claim, characterised in that it comprises a further limb (14a) arranged centrally in relation to the other limbs
(14, 15) of the tent frame (10), which further limb (14a) is fixed relative to the
hub (12).
7. A tent frame (10) according to claim 6, characterised in that the fixed central limb (14a) is in the same position relative to the hub (12) for
both the erect condition of the tent frame (10) and the collapsed condition of the
tent frame (10).
8. A tent frame (10) according to any preceding claim, characterised in that the said second set of pivots (24) are arranged between two pivots of the said first
set of pivots (16).
9. A tent frame (10) comprising a hub (12) from which extends a plurality of limbs (14,
15), respective ends of which are secured to the hub (12) by way of respective pivots
(16, 24), so that each limb (14, 15) is pivotable between a stow position and an extended
position it adopts when the frame (10) is in use, characterised in that at least one of the limbs (15) can be retained in its extended position by means
of interengaging parts (66, 60) respectively mounted on the hub (12) and the hub end
of the said at least one of the limbs (15), at least one of those interengaging parts
(66) being slidable between a first position, in which it accommodates movement of
the other (60) of those parts whilst the said at least one of the limbs (15) is brought
into its extended position, and a second position in which it engages the said other
of those parts (60) to retain the said at least one of the limbs (15) in its extended
position.
10. A tent frame (10) according to claim 9, characterised in that at least one (66) of the interengaging parts is spring-loaded towards the said second
position, so that upon movement of the said at least one of the limbs (15) towards
its extended position, the said one of those interengaging parts (66) is slid by the
said other of those interengaging parts (60) to its said first position, and so that
upon the said at least one of the limbs (15) reaching its extended position, the said
one of those interengaging parts (66) snaps back to its second position so that those
two parts (66, 60) can engage one another in such a manner as to retain the limb (15)
in its extended position.
11. A tent frame (10) comprising a hub (12) from which extends a plurality of limbs (14,
15), respective ends of which are secured to the hub (12) by way of respective pivots
(16, 24), so that each limb (14, 15) is pivotable between a stow position and an extended
position it adopts when the frame (10) is in use, characterised in that at least one of the limbs (15) is provided with a slider (72) coupled to the said
at least one of the limbs (15) in such a manner as to be slidable therealong away
from and towards the hub (12), there being two cross-members (74, 76) pivotally connected
to the slider (72) and extending therefrom to respective pivots (82, 84) on respective
ones of the limbs (15) which are on opposite respective sides of the said at least
one of the limbs (15), whereby when the limbs (14, 15) are moved to their extended
positions, the slider (72) can slide along the limb (15) on which it is provided away
from the hub (12) so that the cross-members (74, 76) retain the said respective ones
(15) of the limbs at a splay angle relative to the said at least one of the limbs
(15).
12. A tent frame (10) according to claim 11, characterised in that the slider (72) can be retained in the position it adopts when the limbs (14, 15)
are in their extended positions by means of a clip, pin, latch or over-centre mechanism.
13. A tent frame (10) according to any one of claims 9 to 12, characterised in that tent frame (10) has one or more of the additional features set out in claims 1 to
8.
14. A tent comprising a tent frame (10) as claimed in any preceding claim together with
sheet material (34) supported by the frame (10).