Note: Descriptions are shown in the official language in which they were submitted.
~124~s
The present invention relates to methods and apparatus for
bending softened multiple channel tubing particularly adapted for
whirlpool systems and, more particularly for use in such systems which
are adapted for use in conventional bathtub installations.
This application is a division of Canadian patent application
Serial No. 332,319, filed on July 23, 1979.
Recently, travelers, businessmen, skiers, golfers, tennis
players and other sportsmen have become increasingly aware of the
benefits of a whirlpool bath in which water is agitated to create an
invigorating whirlpool motion. The swirling waters of a whirlpool bath
are believed by many to calm frayed nerves, ease the pain of aching
muscles, and soothe sore feet. In recognition of the increasing popu-
larity of whirlpool baths, many motels, hotels, and inns are installing
in-room whirlpool baths in an effort to gain a competitive edge. How-
ever, in order to be profitable, and therefore result in a true compe-
titive edge, such whirlpool baths must be simple to install, operate,
and service.
Some known whirlpool baths, e.g. the one disclosed in Jacuzzi
U.S. Patent No. 3,571,820, include a number of jet assemblies spaced
around the outer periphery of a bathtub for agitating water in the
bathtub. In these known whirlpool baths, water and air supply piping
systems, including several pieces of pipe joined together by elbows
and T-fittings, are used to supply each of the jet assemblies with
water and air, respectively, i.e., separat`e air supply and water supply
pipes. The installation of the elbows and T-fittings increases con-
struction time and costs, in terms of both materials and labor. The
elbows and T-fittings also complicate repairs and replacement.
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112~9'75
Everston U.S. Patent No. 3,263,678 discloses a
therapeutic bathtub having a plurality of aspirating fit-
tings designed specifically to diffuse finely divided air
bubbles throughout the water in the bathtub. Thus, the
aspirating fittings perform a function, i.e., the diffusion
of finely divided bubbles, which is different than and may
be performed in addition to the conventional function of
providing agitated water to produce a whirlpool bath. Never-
theless, the aspirator fittings are supplied water and air
from a piping network in which several individual pieces of
pipe are interconnected by elbows and T-fittings.
Efforts have been made to avoid the problems and
disadvantages resulting from the use of elbows and T-
fittings in whirlpool systems. For instance, in Mathis U.S.
Patent No. 3,890,656, there is disclosed a whirlpool jet
for bathtubs which purportedly eliminates the use of T-
fittings by making all water and air pipe connections
directly to a corresponding water jet outlet. However,
because the water jet outlets described and claimed in the
Mathis patent are actually T-fittings, which have been
designed to perform a jetting function, the water jet
outlets of each pair of adjacent outlets are connected by
separate pieces of water and air supply pipes. The pro-
vision of several pieces of pipe not only complicates
installation, thereby increasing initial construction time
and costs, but also complicates repairs and replacements
resulting in increased maintenance costs. Furthermore, inas-
much as the individual outlets are permanently cemented to
the water and air supply pipes, the outlets are totally
incapable of quick and easy on-site removal independently
of the water and air supply pipes for inspection, cleaning
and replacement purposes.
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Many of the disadvantages and shortcomings of the whirlpool
baths and other devices discussed above are overcome by utilizing new
and improved piping arrangements for use in a whirlpool system which
normally includes a plurality of outlets spaced around the interior of
a water receptacle, e.g. a bathtub, a water supply channel connected
to a source of water, and an air supply channel connected to a source
of air. If the channels are adjacent channels of a single piece of
multiple channel tubing, the tubing can be made economically from a
suitable thermoplastic material which is extruded in a continuous
straight length. One aspect of the present invention provides a
method for bending the thermoplastic multiple channel tubing, whereby
the shape of the length of tubing can be matched with the outer contour
of a bathtub. In accordance with a broad aspect of this invention, a
method is provided for bending thermoplastic, multiple channel tubing
having a predetermined cross-sectional shape and a partition of a pre-
determined shape which separatés the tubing into a multiplicity of
channels, comprising the steps of inserting the tubing into a hot liquid
bath, maintaining ,the tubing in the bath until the tubing is bendable,
bending the tubing into a desired shape, and supporting the softened
2~ tubing, including the partition, during the bending step so as to sub-
stantially maintain the predetermined cross-sectional shape of the
tubing while also substantially maintaining the predetermined shape of
the partition as well as its proper orientation with respect to the
rest of the tubing.
By a variant thereof the direction of bending is substanti-
ally parallel to the partition.
By another variant, the direction of bending is substantially
perpendicular to the partition.
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By a still further variant, the supporting step includes
providing a plurality of holes through the tubing, including the par-
tition, at predetermined locations along the length of the tubing and
prior to the softening thereof, inserting a pég through each of said
holes after softening of the tubing, and clamping the tubing in the
vicinity of each of the holes after the softening of the tubing.
In other words, by an embodiment of the method of this inven-
tion, the tubing is maintained in a bath of hot liquid, e.g. triethyl-
ene glycol heated to 230-260-F., until the thermoplastic mater-
ial becomes soft and bendable. As long as the thermoplastic materialremains soft, the tubing can be bent into almost any desired shape or
configuration. If the multiple channel tubing includes a pair of
channels separated by a thermoplastic partition, the softened tubing
is supported during the bending and cooling of the tubing so as sub-
stantially to maintain the original cross-sectional shape of the tub-
ing, as well as the shape of the partition and its proper orientation
with respect to the rest of the tubing.
A further aspect of the present invention involves apparatus
adapted to maintain the cross-sectional shape of the softened tubing.
The apparatus also maintains the shape of the partition and its proper
orientation with respect to the rest of the tubing.
By one broad aspect thereof, apparatus is provided which
is useful in bending softened multiple channel tubing having a pre-
determined cross-sectional shape and a partition of a predetermined
shape which separates the tubing into a multiplicity of channels, com-
prising supporting means for supporting the softened tubing, includ-
ing the partition, so as to substantially maintain the predetermined
cross-sectional shape of the softened tubing while also substantially
maintaining the predetermined shape of the partition as well as its
proper orientation with respect to the rest of the tubing.
`,~
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In one embodiment, the apparatus includes a first member
positioned on one side of the tubing and a second mem~er positioned on
an opposite side of the tubing, the members having surfaces with a con-
tour which substantially matches at least a portion of the cross-sec-
tional shape of the tubing.
By a variant thereof one of the members includes a projecting
member removably extending through the other member, the projecting
member removably extending through the second member, the projecting
member cooperating with the second member to maintain the shape of
the partition and its proper orientation with respect to the rest of the
tubing.
For a more complete understanding of the invention, reference
may be had to the following description of the exemplary embodiments
taken in conjunction with the accompanying drawings, in which:
Figure 1 is a perspective view of one embodiment of a whirl-
pool system constructed in accordance with an aspect of the invention
described in the above identified parent application;
Figure 2 is a partial cross-sectional view of a first exem-
plary embodiment of a connector assembly constructed in accordance with
an aspect of the invention described in the above ident~fied parent
application;
Figure 3 is a cross-sectional view of a nozzle utilized in
the connector assembly illustrated in Figure 2;
Figure 4 is a partial elevational view of a second exemplary
embodiment of a whirlpool system constructed in accordance with an
aspect of the invention described in the above identified parent
application;
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Figure 5 is a cross-sectional view of a second exemplary
embodiment of a connector assembly constructed in accordance with an
aspect of the invention described in the above identified parent appli-
cation;
Figure 6 is a cross-sectional view of a third exemplary
embodiment of a connector assembly constructed in accordance with an
aspect of the invention described in the above identified parent
application;
Figure 7 is a cross sectional view of a fourth exemplary
embodiment of a connector assembly constructed in accordance with an
aspect of the invention described in the above identified parent appli-
cation;
Figure 8 is a cross-sectional view of a fifth exemplary
embodiment of a connector assembly constructed in accordance with an
aspect of the invention described in the above identified parent
application;
Figure 9 is a cross-sectional view of a sixth exemplary
embodiment of a connector assembly constructed in accordance with an
aspect of the invention described in the above identified parent
application;
Figure 10 is a perspective view of a third exemplary embodi-
ment of a whirlpool system constructed in accordance with an aspect
of the invention described in the above identified parent application;
and
Figure 11 is an exploded view of a clamp assembly useful
in bending dual channel tubing in accordance with one aspect of the
present invention.
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llZ4!375
The Overall System
The whirlpool system shown in Figure 1 includes a number
of outlets 10 which are spaced apart around the periphery of a bath-
tub 12. Each of the outlets 10 extends through a sidewall 14 of the
bathtub 12 below a predetermined water level line and is connected
to a continuous loop of dual channel tubing 16 by a connector assem-
bly 18. The loop of dual channel tubing 16 has a shape which gener-
ally matches the outer contour of the bathtub 12.
A pump 20, driven by a motor 22, receives water from the
bathtub 12 through a return line 24, which communicates with the
interior of the bathtub 12 below its predetermined water level line.
Water under pressure is supplied from the pump 20 to one channel of
the dual channel tubing 16 through a flexible hose 26 and a saddle .
clamp type connector 28. Another saddle clamp type con-
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l~Z4975
nector 30 is connected by a flexible hose 32 to an air
port 34 located above the predetermined water level line of
the bathtub 12, so that the port 34 will always be open to
the atmosphere for supplying air to the other channel of
the dual channel tubing 16 at atmospheric pressure.
Other exemplary embodiments of the whirlpool
system of Figure 1 are illustrated in Figures 4 and 10. The
various elements illustrated in Figures 4 and 10 which cor-
respond to elements described above with respect to
Figure 1 have been designated by corresponding reference
numerals increased by 100 and 200, respectively. The embodi-
ments of Figures 4 and 10 operate in the same manner as the
embodiment of Figure 1, unless it is otherwise stated.
Referring now to Figure 4, a pump 120 and a com-
pressor 136 are driven by a double-ended motor 122, so that
air at greater than atmospheric pressure can be supplied to
one channel of dual channel tubing 116 through a supply
line 138 and a saddle clamp type connector 130. Alter-
natively, the pump 120 and the compressor 136 can be driven
by a pair of separate motors. The pressure of the air can
be regulated from inside the bathtub 112 by a conventional
air pressure regulator 140 communicating with the supply
line 138. Supplying air under pressure via the compressor
136, the supply line 138, and the regulator 140 eliminates
the need for the flexible hose 32 and the port 34 of the
embodiment of Figure 1.
The whirlpool system shown in Figure 10 includes
dual channel tubing 216 and a number of connector assem-
blies 218 removably mounted to the dual channel tubing 216,
which therefore acts as a header. Because the dual channel
tubing 216 is located at one end of a bathtub 212, the
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connector assemblies 218 are relatively remote from at
least some outlets 210, each of which is connected to a
corresponding one of the connector assemblies 218 by a
flexible hose 242 or any other suitable conduit. The loca-
tion of the dual channel tubing 216 can be changed
depending upon the configuration of the overall whirlpool
system.
A saddle clamp type connector 244 replaces the
saddle clamp type connectors 28 and 30 of the embodiment
shown in Figure 1. More particularly, the saddle clamp type
connector 244 has an upper clamp member 246, which connects
a pump 220 to one channel of the dual channel tubing 216,
and a lower clamp member 248, which connects an air port
234 to the other channel of the dual channel tubing 216.
The Nozzle Ty e Connector Assembly Embodiments
p
Referring now to Figures 2 and 3, there is shown
dual channel tubing 310. It has a cylindrical shape,
although any other suitable shape may be used, and a
partition 312 extending across the interior of the tubing
310 to form an air channel 314 and a water channel 316.
Although the partition 312 is shown extending across a
diameter of the dual channel tubing 310, the partition 312
may extend across any chord of the tubing 310.
At each location where a connector assembly 318
is to be inserted through the dual channel tubing 310, a
pair of holes 320, 322 is provided, the hole 320 being
formed in the top of the tubing 310 diametrically opposite
the hole 322, which is formed in the bottom of the tubing
310. Another hole 324, having a diameter substantially
equal to the diameter of the hole 320 but somewhat less
than the diameter of the hole 322, is formed in the par-
tition 312 and aligned with the holes 320, 322, so that a
nozzle 326 can be inserted therethrough.
112~9~5
The nozzle 326, which forms a part of a corres-
ponding connector assembly 318, includes a small diameter
portion 330, which extends through the holes 320, 324 and
the water channel 316, and a large diameter portion 332,
which extends through the hole 322 and into the air channel
314. An 0-ring 334 interposed between the partition 312 and
a shoulder 336 formed at the juncture of the small diameter
portion 330 and the large diameter portion 332 forms a
fluid-tight seal between the air channel 314 and the water
channel 316.
A fluid passageway 338 (see Fig. 3) runs the
length of the nozzle 326 and communicates with the air
channel 314 and the water channel 316 through an air inlet
opening 340 and a water inlet opening 342, respectively. To
facilitate drainage of water from the dual channel tubing
310, the bottoms of the air inlet opening 340 and the water
inlet opening 342 are at an elevation substantially no
higher than the elevation of the bottoms of the air chan-
nel 314 and the water channel 316, respectively. The por-
tion of the passageway 338 between the air inlet opening340 and the water inlet opening 342 includes a venturi 344
(see Fig. 3) designed to enhance the mixing of water and
air in the passageway 338 and to speed the flow of water
and air through the passageway 338.
The free end of the small diameter portion 330
extends upwardly through the hole 320 formed in the top of
the dual channel tubing 310 and is provided with an exter-
nally threaded portion 346 designed to threadedly engage an
internally threaded cap 348. By removing the cap 348,
access may be had to the passageway 338 for the purposes of
inspection and cleaning.
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llZ~9~'5
An 0-ring 350, disposed about the free end of the
small diameter portion 330, seals the hole 320 formed in
the top of the dual channel tubing 310. The 0-ring 350 is
held in sealing engagement against the top of the tubing
310 by a jaw member 352, slidably received on the free end
of the small diameter portion 330 of the nozzle 326, and a
lock nut 354, having an internally threaded portion (not
shown) which threadedly engages the externally threaded
portion 346 of the free end of the small diameter portion
330, for forcing the jaw member 352 into positive engage-
ment with the 0-ring 350.
The free end of the large diameter portion 332 of
the nozzle 326 extends downwardly through the hole 322 in
the bottom of the dual channel tubing 310. An externally
threaded portion 356 provided on the free end of the large
diameter portion 332 threadedly engages an internally
threaded portion (not shown) formed in the vertical end 358
of a relatively rigid elbow 360. The horizontal end 362 of
the elbow 360 has in internally threaded portion 364 which
threadedly engages an externally threaded portion 366
formed on a stem portion 368 of an outlet 370. Although the
elbow 360 is shown as having a 90 bend, the bend can be
more or less than 90 depending upon the designs and
relative positions of the nozzle 326 and the outlet 370.
Moreover, the elbow 360 could be replaced by a flexible
hose or any other suitable connecting device.
An 0-ring 372, disposed about the free end of the
large diameter portion 332, seals the hole 322 formed in
the bottom of the dual channel tubing 310. The 0-ring 372
is held in sealing engagement against the bottom of the
tubing 310 by a jaw member 374, which is slidably received
llZ~975
on the free end of the large diameter portion 332 and
forced into positive engagement with the 0-ring 372 by a
lock nut 376 threadedly engaged on the free end of the
large diameter portion 332.
A fluid-tight seal is also formed between the
outlet 370 and a sidewall 382 of a bathtub 384 by an O-ring
386, a gasket 388, and a lock nut 390. The 0-ring 386 is
disposed about the stem portion 368 of the outlet 370
between the outlet 370 and the sidewall 382. The gasket 388
and the lock nut 390 are also disposed about the stem
portion 392, but on the opposite side of the sidewall 382
from the 0-ring 386. The lock nut 390 threadedly engages
the externally threaded portion 366 of the stem portion 368
so as to force the 0-ring 386 and the gasket 388, both of
which can be made of rubber or any other suitable material,
into sealing engagement with the sidewall 382 of the bath-
tub 384.
Referring now to Figures 6 and 9, there are shown
two further embodiments of the exemplary connector assembly
embodiment of Figures 2 and 3. The various elements illus-
trated in Figures 6 and 9 which correspond to elements
described above with respect to Figures 2 and 3 have been
designated by corresponding reference numerals increased by
100 and 200, respectively. Unless otherwise stated, the
further embodiments operate in the same manner as the
embodiment of Figures 2 and 3.
In the embodiment of Figure 6, a horizontally
extending nozzle 426 has a small diameter portion 430 which
communicates with a water channel 416 but does not extend
therethrough. The interior end of a passageway 438
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extending through the nozzle 426 functions as a water
inlet, thereby replacing the water inlet opening 432 of the
embodiment of Figures 2 and 3. An outlet 470 is adapted to
threadedly engage a threaded portion 456 on the nozzle 426.
An 0-ring 472, jaw member 474, gasket 488, and lock nut 476
are positioned between a sidewall 482 of a bathtub 484 and
the outer circumferential surface of a continuous loop of
dual channel tubing 410 to form a water-tight seal for an
opening in the side of the tubing 410. The lock nut 476
forces the 0-ring 472 into sealing engagement with the dual
channel tubing 410. Another 0-ring 486 and a gasket 488 are
forced into sealing engagement with the sidewall 482 of the
bathtub 484 by the outlet 470. Although the direct con-
nection of the nozzle 426 with the outlet 470 eliminates
the elbow 360 of the embodiment of Figures 2 and 3, it
necessitates arranging the water channel 416 alongside an
air channel 414, rather than above it.
The embodiment of Figure 9 also includes a con-
tinuous piece of dual channel tubing 510 having a water
channel 516, which is arranged alongside an air channel
514. Because the elbow 360 of the embodiment of Figures 2
and 3 is dispensed with, an outlet 580 is internally
threaded so that it can threadedly engage an externally
threaded portion 556 on the free end of a large diameter
portion 532 of a nozzle 526. O~rings 572, 586, jaw member
574, gasket 588, and lock nut 576 form a water-tight seal
for an opening 522 in the side of the tubing 510 and an
opening in a sidewall 582 of a bathtub 584.
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The Saddle Clamp Type Connector Assembly Embodiments
As shown in Figure 5, a saddle clamp 610 includes
a pair of clamp members 612, 614. The saddle member 612 is
positioned on the upper side of a piece of dual channel
tubing 616, the saddle member 614 being positioned on the
lower side of the tubing 616 substantially diametrically
opposite the saddle member 612.
The saddle member 612 has holes 618 passing com-
pletely therethrough. The holes 618 are aligned with blind
bores 620 in the adjacent surface of the saddle member 614.
The holes 618 and the bores 620 are internally threaded so
as to receive externally threaded bolts 622 which maintain
the saddle members 612 and 614 clamped about the tubing
616. The bolts 622 also permit the position of the saddle
members 612, 614 to be adjusted with respect to each other.
The saddle member 614 includes a passageway 624
extending therethrough below the dual channel tubing 616. A
water inlet opening 626 communicates between a water chan-
nel 628 of the tubing 616 and the passageway 624. The
passageway 624 also communicates with an air channel 630
through an air inlet opening 632 in the saddle member 614.
The portion of the passageway 624 between the water inlet
opening 626 and the air inlet opening 632 includes a
venturi 634 for enhancing the mixture of water and air and
for speeding the flow of the water and air through the
passageway 624. The end of the passageway 624 nearest the
air inlet opening 632 is internally threaded so as to
receive an externally threaded portion of an outlet (not
shown) mounted in the sidewall of a water receptacle, such
as a bathtub. A plug 636 has an externally threaded portion
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638 which threadedly engages an internally threaded portion
of the passageway 624 at the opposite end thereof. An
0-ring 640 is disposed about a shank portion 642 of the
plug 636 to provide a water-tight seal.
The saddle member 612 has an internally threaded
opening 644 which communicates at one end with the air
channel 630 of the tubing 610. An externally threaded plug
646 is threadedly received in the opening 644, so that the
air channel 630 may be selectively opened and closed to the
atmosphere.
Figures 7 and 8 illustrate further exemplary
embodiments of the connector assembly of Figure 5. The
various elements illustrated in Figures 7 and 8 which cor-
respond to elements described above with respect to Fig-
ure 5 have been designated by corresponding reference
numerals increased by 100 and 200, respectively. The embodi-
ments of Figures 7 and 8 operate in the same manner as the
embodiment of Figure 5, unless it is otherwise stated.
Referring to Figure 7, a water inlet opening 726
of a passageway 724 communicates with the interior of a
water supply conduit 750. An air inlet opening 732 communi-
cates between the passageway 724 and the interior of an air
supply conduit 752.
As shown in Figure 8, a piece of dual channel
tubing 816 is flanked on either side by saddle members 812,
814. The tubing 816 includes a partition 860 which extends
across the interior thereof along a diameter or any other
chord. An aperture 862 in the partition 860 permits a water
channel 828 on one side of the partition 860 to communicate
with an air channel 830 on the other side of the partition
860, the aperture 862 acting as a venturi for enhancing the
mixture of water and air and for speeding the flow of water
and air out of the tubing 816 and through a passageway 824
provided in the saddle member 814.
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llZ497S
A vertical opening 842 in the saddle member 814
connects the air channel 830 to the a-tmosphere. A plug 844
threadedly received in the opening 842 permits the selec-
tive opening and closing of the air channel 830 to the
atmosphere.
A horizontal internally threaded opening 870 in
the saddle member 812 communica-tes with a water channel 828
of the tubing 816. A plug 872 has an externally threaded
opening 870 in the saddle member 812 for permitting access
to the water channel 828. An O-ring 876 disposed about a
shank portion 878 of the plug 872 forms a water-tight seal.
Method of Bending Dual Channel Tubing
When a piece of dual channel tubing, like the
dual channel tubing described above, is extruded in a
single straight length of thermoplastic material, the
tubing must be bent in order to match the contour of a
water receptacle, such as a bathtub. One especially advan-
tageous method of bending such tubing involves using a
Greenlee No. 850 PVC Bender which is filled with triethy-
lene glycol. After the triethylene glycol is heated toabout 230-260F., the dual channel tubing is inserted i~to
the bath and maintained therein until the thermoplastic
material is sufficiently soft so as to render the tubing
bendable. The tubing can then be bent, either in a direc-
tion perpendicular to or parallel to the partition ex-
tending across the interior of the tubing.
If difficulties are encountered in maintaining
the original shape of the softened tubing, including the
partition, during its cooling, the following procedure,
which is described below with reference to Figure 11, may
be followed. Referring to Figure 11, dual channel tubing
* ~fo~é~
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1124975
910 has a partition 912 whi.ch runs the length thereof. At
predetermined locations, corresponding to the locations
where a connector assembly will be attached to the tubing,
three aligned holes 914, 916, 918 are formed in the tubing
910 prior to its softening. The holes 914, 916 are formed
in opposite sides of the tubing 910, the other hole 918
being formed in the partition 912.
Either prior to, simultaneously. with or imme-
diately after the bending of the tubing 910 into a desired
. shape, a peg 920, which extends upwardly from a lower
saddle member 92~ of a saddle clamp 924, is inserted
through the holes 914, 916, 918, and into a hole 926 in an
upper saddle member 928 of the saddle clamp 924 to he~p
maintain the original shape of the partition 912 as well as
its proper orientation with respect to. the rest of the
tubing 910. The saddle members 922 and 928 are then clamped
over the outer surface of the tubing to help maintain its
- original cross-sectional shape, thereby :aiding in the sup-
port of the softened partition 912.
The tubing 910 can be cooled at room temperature.
Alternatively, cooling of the tubing 910 can be expedited
by passing a cool fluid, such as air or water, in and/or
around the softened tubing 910;
