Note: Descriptions are shown in the official language in which they were submitted.
CA 02532429 2006-O1-10
1 "VERTICALLY ACTUABLE ROOF COVER FOR A SPA"
2
3 FIELD OF THE INVENTION
4 Embodiments of the invention relate to spa covers and more
particularly to spa covers which are moveable vertically between a position
6 directly atop the spa and a position elevated above the spa to act as a roof
7 structure during spa use.
8
9 BACKGROUND OF THE INVENTION
It is known to cover hot tubs or spas to prevent contamination due
11 to environmental debris, such as leaves, pollens and the like, to prevent
12 excessive evaporation when the spa is not in use and to act as a safety
measure
13 to prevent animals, small children and the like from falling into the water
when
14 unsupervised.
Most conventional spa covers are fabric covered foam structures
16 which rest atop the spa when the spa is not in use and which are removed,
17 either by sliding off the tub or by folding at a middle and lifting to a
position away
18 from the top of the tub, such by a support frame wherein the cover is
suspended
19 vertically in the folded position adjacent a side of the tub. The fabric
covers may
be susceptible to chemical vapors, such as chlorine, are prone to tearing at
21 seams exposing the foam layers to the elements and to the steam and vapors
22 from the tub and are generally susceptible to normal wear and tear
necessitating
23 multiple replacements during the life of the average spa.
24 It is known to provide fixed structures built around the hot tub to
provide an element of protection for use during inclement weather or to
prevent
CA 02532429 2006-O1-10
1 excessive exposure to the sun. Most often the structure is independent of
the
2 cover and remains in a fixed position around the tub, the roof portion being
fixed
3 above the spa to permit use of the spa. While these structures may meet the
4 needs of the user by providing a rigid or semi rigid roof structure, they
add
additional expense by requiring a spa cover to be used as well.
6 Conventional spa covers are not designed to handle the weight of
7 a person or persons resting on the cover. As the spa covers are typically
flat
8 however, individuals may be encourage to walk or otherwise provide undue
9 weight on the cover, such as when shoveling snow from a deck in which the
spa
is recessed, which results in damage not only to the cover but to the spa
itself.
11 Others have attempted to provide domed rigid or semi-rigid cover
12 structures which, like the conventional cover, reside atop the spa when in
use
13 and which are pivoted or slid laterally away from the spa when the spa is
to be
14 used.
It is known to provide a vertically actuable cover to a swimming
16 pool or a spa. US Patent 3,566,420 to Peterson et al teaches hydraulic
actuators
17 used to raise and lower a cover from a swimming pool and US Patent
6,718,566
18 to Wilson teaches a plurality of telescoping and threaded sections which
are
19 used to raise and lower a cover over a spa.
There remains interest in the industry to find reliable, relatively
21 simple and inexpensive lift systems for raising and lowering roof
structures over
22 spas, which can act to replace a conventional spa cover when in a lowered,
spa
23 engaging position and which act as a roof when in the raised position.
24
2
CA 02532429 2006-O1-10
1 SUMMARY OF THE INVENTION
2 A cover assembly for a structure, such as a spa, is vertically
3 actuated between a lowered position atop the spa to an elevated position
above
4 the spa where the cover acts as a roof over the spa. The actuation of the
cover
is accomplished using actuation members which support the cover and which
6 employ unique lifting means, such as a rack and pinion system or a tension
7 member and rotatable guides, powered by a motor. The lifting means are
8 housed within telescoping tubular members which act to provide an aesthetic
9 covering for the lifting means and which may or may not form a part of the
lifting
means structure.
11 In a broad aspect therefore, a vertically-actuable cover assembly
12 for a structure comprises: a cover; and two or more actuation members for
13 supporting the cover, the two or more actuation members being actuable
14 between a lowered position atop the structure to an elevated position above
the
structure so as to act as a roof thereover, wherein the two or more actuation
16 members further comprise: a first lift structure mounted on a base fixed
relative
17 to the structure; a second lift structure operatively connected to the
first lift
18 structure and actuable to be raised and lowered for raising and lowering
the
19 cover; a third upper lift structure operatively connected to the second
lift
structure; a rotatable guide supported adjacent a top end of the second lift
21 structure; a cable connected between the first structure and extending
about the
22 rotatable guide for connection to a bottom end of the third lift structure;
and drive
23 means for driving the second lift structure to be lifted and lowered
relative to the
24 first lift structure, wherein the rotatable guide is lifted and lowered by
the second
3
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1 lift structure so as to passively cause the cable to lift the upper lift
structure
2 relative to the second lift structure.
3 The cover is supported on a plurality of actuation members,
4 typically one at each corner of the cover, having one or more motors. In a
preferred embodiment, a plurality of electric motors are connected through a
6 single circuit so as to co-ordinate the actuation members to support and
7 vertically actuate the cover.
8 Preferably, stops are formed at top and bottom ends of the
9 telescoping tubular members to limit the upward travel of the telescoping
members within each other to prevent the telescoping members from becoming
11 disconnected during elevation of the cover and to lift the intermediate
member
12 with the upper tubular member.
13 In one embodiment, a rack and pinion lifting system is used
14 wherein the first lift structure is a pinion or worm gear mounted on a
rotatable
shaft, the second lift structure is a rack and the third lift structure is the
upper
16 telescoping member which supports the cover. An electric motor drives the
shaft
17 to rotate the worm gear which in turn engages the rack to be lifted and
lowered
18 along with the structures connected thereto. A cable is connected between
the
19 rack and an upper telescoping member, which forms part of the lifting
structure
and upon which the cover is supported, for assisting in raising and lowering
21 cover. The cable is guided by a pulley which is connected at a top end of
the
22 rack. As the rack is moved so is the pulley at the top of the rack which
causes
23 the cable to passively lift or lower the upper telescoping member to raise
and
24 lower the cover. Limit switches act to stop the motor when the cover has
reached
the elevated or lowered position.
4
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1 In an alternate embodiment, a tension cable and rotatable guide
2 system is used wherein the first lift structure is a housing mounted on a
base for
3 telescopically housing a linearly extending member and the drive means is a
4 tension member which is driven about a plurality of rotatable guides which
are
positioned at the top and bottom of the housing and the top and bottom of the
6 second lift structure. One of the rotatable guides, preferably the guide at
the
7 bottom of the housing, is driven by a motor. The third lift structure is a
linearly
8 extending member telescopically housed in the second lift structure and to
which
9 the cover is connected
In a preferred embodiment the tension member is a chain or belt
11 and the rotatable guide are sprockets. Further a biasing means, such as a
12 hydraulic cylinder is provide to assist in lifting the second lift
structure. The pulley
13 over which the cable extends is rotatably connected by a bracket adjacent
the
14 top of the second lift structure and further to a hydraulic arm of the
hydraulic
cylinder. The cylinder arm is driven upwards as the chain lifts the second
lift
16 structure thus reducing the load on the motor.
5
CA 02532429 2006-O1-10
1 BRIEF DESCRIPTION OF THE DRAWINGS
2 Figure 1 is a perspective view of a spa cover according to one
3 embodiment, shown in a raised position;
4 Figure 2 is a perspective view according to Fig. 1 shown in a
lowered position;
6 Figure 3a is a longitudinal sectional side view of an actuation
7 mechanism for raising and lowering the spa cover, shown in the lowered
8 position;
9 Figure 3b is a longitudinal sectional side view according to Fig. 3a,
shown in the raised position;
11 Figure 4a is a longitudinal sectional front view according to Fig. 3a,
12 in the lowered position;
13 Figure 4b is a longitudinal sectional front view according to Fig. 3a,
14 in the raised position;
Figure 5 is a detailed view of an embodiment of the actuation
16 mechanism, more particularly a worm gear and rack;
17 Figure 6 is a perspective view of the worm gear and rack of Fig. 5
18 shown in the lowered position and illustrating an alternate embodiment for
19 connection of the upper tubular member
Figure 7 is a schematic sectional view of an embodiment of an
21 actuation mechanism having two telescoping tubular members, the upper
tubular
22 member being connected to the rack;
23 Figure 8 is a schematic section view of an embodiment of the
24 invention according to Figs. 3a-4b having three telescoping tubular
members,
6
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1 the upper tubular member being connected passively to the rack through a
cable
2 and pulley;
3 Figure 9 is a schematic of a circuit for independently operating of a
4 plurality of gear motors for rotationally powering worm gears;
Figure 10 is a schematic of a circuit for operating the plurality of
6 gear motors according to Fig. 9, in series;
7 Figure 11 is a schematic of another embodiment of the actuation
8 mechanism, more particularly a tension member and rotational guide system,
9 shown in a raised position, the telescoping tubular members having been
removed for clarity;
11 Figure 12 is a schematic of the embodiment according to Fig. 11, in
12 a lowered position;
13 Figure 13 is a partial perspective view of the embodiment of Fig. 11
14 illustrating the telescoping arrangement of the lift structures in the
actuation
means; and
16 Figure 14 is an end view of the actuation means according to Fig.
17 11, the tension member removed for clarity.
7
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1 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
2 Having reference to Figs. 1 and 2, a cover apparatus 1 for a
3 structure 2, such hot tub or spa, comprises a cover 3 supported on actuation
4 members 4, typically positioned at each corner of the spa 2. The actuation
members 4 elevate the cover 3 from a lowered position, wherein the cover 3
6 rests atop or adjacent a top edge 5 of the spa 2, to a raised position,
wherein the
7 cover 3 is supported over the spa 2 to act as a roof.
8 As shown in Figs. 3a,3b and 11, the actuation members 4
9 comprise a first lift structure 30 mounted on a base 13 fixed relative to
the
structure 2. A second lift structure 19 is operatively connected to the first
lift
11 structure 30 and is actuable to be raised and lowered relative thereto for
raising
12 and lowering the cover 3 supported thereon. A third upper lift structure 15
is
13 operatively connected to the second lift structure 19 and actuable to be
raised
14 and lowered relative thereto. A rotatable guide, such as a pulley 23, is
supported
adjacent a top end of the second lift structure 19 and a first flexible
tension
16 member such as a cable 16 is connected between the first structure 30 or
the
17 base 13 and extending about the rotatable guide 23 for connection to a
lower
18 end 21 of the third lift structure 15. Drive means 40, powered by a motor
31, is
19 provided for driving the second lift structure 19 to be lifted and lowered
relative to
the first lift structure 30 and in doing so lifts the rotatable guide 23 to
passively
21 cause the cable 16 to lift the upper lift structure 15 relative to the
second lift
22 structure 19.
23 As shown in Fig. 3a-6 and in one embodiment, the actuation
24 members 4 comprise a rack and pinion system 10 for raising and lowering the
cover 3. Each actuation member 4 is housed within two or more telescoping
8
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1 tubular members 11. The tubular members 11 may be, but are not limited to
2 being circular, rectangular or square in cross-section. Further, the tubular
3 members can form a part or all of the lift structures 30, 19 15 or shroud
same.
4 Preferably, each actuation member 4 is housed within three telescoping
tubular
members 11, a lower tubular member 12 secured to the base 13, an
6 intermediate tubular member 14 and an upper tubular member 15 upon which
7 the cover 3 is supported. The rack and pinion system 10 is connected thereto
for
8 active actuation of at least the second lift structure 19 and with it the
intermediate
9 tubular member 14. The upper tubular member acts is the third lift structure
15
and is connected thereto through cable 16 which is anchored, at a first end
17, to
11 the base 13 or to an upper end 18 (Fig. 6) of a rack 19 of the rack and
pinion
12 system 10 for movement therewith and, at a second end 20, to a lower end 21
of
13 the upper tubular member 15. The cable 16 is guided at an upper end 22 of
the
14 rack 19 by the pulley 23.
With reference to Figs. 7 and 8, preferably, a stop 24a is formed at
16 an upper end 25 of the lower tubular member 12 for engaging a stop 24b at a
17 lower end 26 of the intermediate tubular member 14 for retaining the
18 intermediate telescoping tubular member 14 in the lower telescoping tubular
19 member 12 and to prevent the intermediate tubular member 14 from being
pulled
aut of the lower tubular member 12, when the cover apparatus 1 is actuated to
21 the raised position. Similarly, a stop 24c is formed at an upper end 28 of
the
22 intermediate member 14 for engaging a stop 24d at the lower end 21 of the
23 upper tubular member 15 for retaining the upper tubular member 15 within
the
24 intermediate tubular member 14 during actuation to the elevated position.
9
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1 Best seen in Figs. 6-8, the rack and pinion system 10 comprises a
2 worm gear 30 which is rotatably connected to the drive means 40, such as an
3 electric gear motor 31, by a rod 32. The worm gear 30 is rotated to raise
and
4 lower the rack 19. For an actuation member 4 having two telescoping tubular
members 11 (Fig. 7), rack 19 directly raises upper telescoping member 15. In
the
6 case of an actuation member 4 having three telescoping tubular members 11
7 (Fig. 8), the rack 19 raises and lowers the upper telescoping member 15 via
the
8 cable 16, the upper tubular member 15 raising and lowering the intermediate
9 tubular member 14 through engagement of the stops 24c,24d. As shown in Fig.
6, the cable 16 is connected at the second end 20 to a ring 33 which is used
for
11 mounting the cable 16 inside the lower end 21 of the upper tubular member
15.
12 Preferably, each actuation member 4 is powered by an electric
13 gear motor 31. Most preferably, all of the gear motors 31 a, 31 b, 31 c, 31
d are
14 connected through a single circuit so that when the circuit is activated,
all of the
actuation members 4 are caused to move at the same time. Limit switches 40
16 are positioned on the rack and pinion system 10 to stop the gear motor 31
when
17 the cover 3 has reached the lowered or the raised position. As shown in
Figs. 9
18 and 10, the gear motor limit switches 40 may be independent (Fig. 9) or in
series
19 (Fig.10).
In an alternate embodiment as shown in Figs. 11-14, the first lift
21 structure 30 is an upwardly linearly extending lower housing which is
connected
22 to the base 13. Best seen in Fig. 14, the second lift structure 19 is an
23 intermediate linearly extending member which is housed telescopically
within the
24 lower housing 30 and the third lift structure 15 is an upper, linearly
extending
member which is housed telescopically within the intermediate member 19.
CA 02532429 2006-O1-10
1 The drive means 40 comprises a durable, flexible tension member
2 41, such as a chain or belt and a plurality of rotational guides 42, such as
3 sprockets or pulleys. At least one of the rotational guides is connected to
a motor
4 31, such as an electric gear motor for driving the tension member 41
thereabout.
The tension member 41 is arranged in a figure 8 having two
6 rotational guides 42 in one loop and two rotational guides 42 in the other
loop.
7 Actuation causes the one loop to be displaced relative to the other loop,
raising
8 one lift structure relative to the other.
9 As shown in Figs. 11 and 12, the tension member 41, such as a
UNIFLEXT"" belt available from Jason Industrial Inc. of Fairfield NJ, 07004,
USA,
11 is connected at either end 43, 44 to the intermediate member 19 and passes
12 about rotational guides 42 positioned at a top 45 and bottom 46 of the
lower
13 housing 30 (a first loop) and at a top 47 and bottom 48 of the intermediate
14 member 19 (A second loop). As the motor 31 drives the at least one
rotational
guide 42, the intermediate member is raised (Fig. 11 ) and lowered (Fig. 12).
16 As in the previously described embodiment, the cable 16 is
17 connected to the lower end 21 of the upper member 15. The pulley 23 is
18 connected to the intermediate member 19 through a bracket 49. As the
19 intermediate member 19 is raised and lowered, the pulley 23 is also raised
and
lowered causing the length of the cable 16 between the pulley 23 and lower end
21 21 to shorten as the intermediate member 19 raises, causing cable 16 to
22 passively raise and lower the upper member 15.
23 In a preferred embodiment, best seen in Figs. 13 and 14, a slot 50
24 is formed along the length of the intermediate member 19 to accommodate
connection of the cable 16 to the lower end 21 of the upper member 15 and to
11
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1 permit movement of the upper member 15 relative to the intermediate member
2 19 for telescoping therein. At least an upper stop 51 is formed along the
slot 50
3 to assist in preventing the upper member 15 from lifting out of the
intermediate
4 member 19.
As shown in Fig. 14, the actuation members 4 in this embodiment
6 are housed within telescoping tubular members 11 so as to aesthetically
cover
7 the lift structures 30, 19 and 15. An upper, lower and intermediate
telescoping
8 member (not shown) are connected to one or more of the lift structures 30,
19,
9 15 so as to move with the lift structures 30, 19, 15 as each are raised and
lowered. For example, the upper telescoping member may be connected to the
11 first lift structure 30 so that when the first lift structure 30 is lifted
the upper
12 telescoping member is raised at the same time. More preferably, the upper
13 telescoping member is further connected to the intermediate telescoping
14 member so that the intermediate telescoping member is passively raised to
cover the second lift structure 19 when the first and second lift structures
30, 19
16 are raised.
17 Optionally, as shown in Figs. 11-14 and in a preferred embodiment,
18 a biasing means 60, such as a hydraulic cylinder, is connected between the
19 lower housing 30 and the intermediate member 19 for assisting in lifting
the
intermediate member 19 to reduce load of the full weight of the cover 3 on the
21 motor 31. Preferably, an actuating arm 61 of the hydraulic cylinder 60,
such as a
22 standard size 10 gas spring available from Industrial Gas Springs Ltd. of
23 Mitcham, Surrey, CR4 4HR, United Kingdom, is connected to the intermediate
24 member 19 through the bracket 49.
12
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1 In a preferred embodiment, the cover 3 is a substantially rigid,
2 domed pyramidal-shaped cover manufactured of a foam core and having a fabric
3 covering such as is known in the industry to provide protection and
insulation as
4 is also known with conventional spa covers. Further, the domed shape is
particularly advantageous for spas which are enclosed in a deck structure to
6 prevent persons or animals from walking or lying on the cover 3 and to
minimize
7 the amount of snow buildup on the cover 3 in snow-prone climates.
13
