Note: Descriptions are shown in the official language in which they were submitted.
CA 02665232 2009-05-04
HEAT EXCHANGE SYSTEM
FIELD OF THE INVENTION
[0001] The present invention relates a novel heat exchange system. More
particularly, the invention relates to a heat exchange system for use with
bathing
apparatus, including showers, bathtubs and whirlpools, that is easy to
install,
maintain and clean.
BACKGROUND OF THE INVENTION
[0002] Heat exchange systems for use with showers or other bathing apparatus
are
known in the art. They are used to recover heat from hot or warm waste water.
In
each of these systems, the spent water flows on one side of a heat exchanger
before
flowing out into the drainage system. Incoming cold water flows on the other
side of
the heat exchanger element and is thereby preheated before being mixed in a
mixer
with hot water or before entering a hot water heating device to be heated
further.
[0003] Sample patent applications and patents in the field include the
following:
Canadian Patent Application No. 2,566,351; Canadian Patent Application No.
2,559,296; United States Patent Application Publication No. 2004/0194916;
International Patent Application No. PCT/SE00/01548; International Patent
Application No. PCT/US2007/019689; International Patent Application
No.PCT/GB2008/002129; UK Patent GB 2 052 698; German Patent No. DE
3319638; German Patent No. DE 3804534; German Patent No. DE 3919544;
German Patent No. DE3932871; German Patent No. DE 4406971; German Patent
No. DE 8600554; German Patent No. DE 19723148; German Patent No. DE
29709630; German Patent No. DE 29717073; German Patent No. DE 29806939;
German Patent No. DE 29815304; German Patent Publication No. DE
202007007907; and Dutch Patent No. NL 1014215.
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[0004] In many instances, the heat exchanger is installed beyond the drain of
the
bathing apparatus and thus comes into with warm waste water after the water
has
flowed through the drain. There are a number of disadvantages with this kind
of
arrangement. First, heat that might otherwise have been captured is dissipated
as it
goes through the drain. Secondly, installing a heat exchanger beyond a drain
unit
requires the expertise of a professional plumber, as it is usually connected
directly to
the plumbing system in one manner or another. Finally, heat exchangers of this
type
can be inconvenient to clean, repair or replace, because they are not readily
accessible.
[0005] In addition, many heat exchange devices that are currently available
are
based on a coil system of some kind. Over time, the accumulation of dirt and
minerals from the waste water can impede the efficiency of such devices. In
some
cases, their complexity can make maintenance and repair difficult.
[0006] The present invention seeks to overcome some of the limitations of heat
exchangers that are currently available.
SUMMARY OF THE INVENTION
[0007] Advantageously, the system of present invention has a simple and clean
design, allowing for ready access to the heat exchange element for
maintenance,
repair and replacement. It is also easy to install in a bathing apparatus and
therefore
does not necessarily require the intervention of a plumbing professional.
[0008] The present invention provides a heat exchange device to recover hot
water
from bathing apparatus. The invention has particular, but not exclusive,
application
to showers.
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[0009] The basic features of the invention include: (a) a shower or bathtub
base; and
(b) a heat exchange plate made of a conductive material. The heat exchange
device
may further include (c) a cover positioned over the heat exchange plate that
serves
as a standing platform for the bather and that compliments the shower or
bathtub
base. The base further includes a draining element through which used water is
evacuated from the shower or bathtub.
[0010] The heat exchange plate is positioned at the bottom of the shower or
bathtub
base, usually flush with the bottom surface. In one embodiment, the bather is
in
direct contact with the heat exchanger, either partially or completely, when
using the
bathing apparatus.
[0011] As stated above, the heat exchanger may optionally be concealed by a
cover,
which is manufactured in a shape and size that is suitable to cover the
opening
created by the base. The cover is made of a non-conductive material. In a
specific
embodiment, the base, heat exchange plate and cover all have a square or
rectangular geometric shape.
[0012] Most of the water originating from of the showerhead or faucet of the
bathing
apparatus flows on top of the heat exchanger before reaching the drainage
system.
The heat exchanger may be covered either fully or partially with a non-
conductive
material.
[0013] The heat exchange system may include a dam that serves to control the
flow
of the waste water to the drain of the bathing apparatus. By slowing down the
flow,
the warm waste water is kept in contact with the heat exchange plate for a
longer
duration, enhancing heat transfer. Other elements may be substituted for or
used
with the dam to achieve this purpose, such as channels or dividing elements,
as
would be appreciated by a person of skill in the art.
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[0014] In any embodiment, the heat exchanger is part of the bathing apparatus
and
the entire assembly is water tight.
[0015] Other objects, advantages and features of the present invention will
become
apparent upon reading of the following non-restrictive description of
embodiments
thereof, given by way of example only with reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 shows (A) an assembled view of a first embodiment of the heat
exchange system of the present invention and (B) an exploded view of this
system;
[0017] Figure 2 shows (A) an alternative assembled view of the heat exchanger
system shown in Figurel, and (B) an exploded view of this system;
[0018] Figure 3 shows (A) a second alternative assembled view of the heat
exchanger system shown in Figurel, and (B) an exploded view of this system;
[0019] Figure 4 shows (A) a third alternative assembled view of the heat
exchanger
system shown in Figurel, and (B) an exploded view of this system;
[0020] Figure 5 shows a second embodiment of the heat exchange system of the
present invention, wherein: (A) is a top plan view of the system, (B) is a
side view of
the system taken along line A-A of Figure 5(A); and (C) is an exploded view of
the
system;
[0021] Figure 6 shows an alternative to the embodiment shown in Figure 5,
wherein:
(A) is a top plan view of the system, (B) is a side view of the system taken
along line
A-A of Figure 6(A); and (C) is an exploded view of the system;
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[0022] Figure 7 shows a second altemative to the embodiment shown in Figure 5,
wherein: (A) is a top plan view of the system, (B) is a side view of the
system taken
along line A-A of Figure 7(A); and (C) is an exploded view of the system;
[0023] Figure 8 shows a third alternative to the embodiment shown in Figure 5,
wherein: A) is a top plan view of the system, (B) is a side view of the system
taken
along line A-A of Figure 8(A); (C) is a side view of the system taken along
line B-B;
(D) is a side view of the system taken along line C-C of Figure 8(A); (E) is a
perspective view of the system fully assembled; and (F) is a perspective view
of the
system without its cover;
[0024] Figure 9 shows a third embodiment of the heat exchange system of the
present invention; wherein: (A) is a top plan view of the system, (B) is a
side view of
the system taken along line A-A of Figure 9(A); and (C) is a perspective view
of the
system fully assembled;
[0025] Figure 10 shows an alternative to the embodiment shown in Figure 9,
wherein:
(A) is a top plan view of the system, (B) is a side view of the system taken
along line
A-A of Figure 10(A); and (C) is an exploded view of the system; and
[0026] Figure 11 shows a fourth embodiment of the heat exchange system of the
present invention, wherein: (A) is a top plan view of the system, (B) is a
side view of
the system taken along line A-A of Figure 11(A); and (C) is a perspective,
partially
exploded view of the system.
DETAILED DESCRIPTION OF THE INVENTION
As will be described more particularly below, the invention comprises four
embodiments, and these embodiments can include additional features.
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[0027] Referring now to Figure 1, there is shown a first embodiment of the
invention
wherein the heat exchange system is generally designated by the number 10. The
system comprises a bathing apparatus 2, illustrated here as a tray-like
element that is
convenient for a shower. The system further comprises a heat exchange element
4,
which is in the general form of a plate, and a gasket 3 for sealing the heat
exchanger
within the bathing apparatus. In order to allow waste water to be eliminated
from the
bathing apparatus 2, a drain 8 is provided.
[0028] In operation, the heat exchange element 4 is connected to a cold water
source
(not shown). When warm from the showerhead or warm waste water from the bather
falls onto the heat exchange element 4, heat from the water is captured by the
heat
exchange element and used to warm the cold water that flows through the body
of
the heat exchanger element, in keeping with heat exchange principles known in
the
art. The cold water, which has now been partially heated by the captured
energy
from the waste water, exits from the heat exchanger (not shown), where it is
directed
to a mixer or to a hot water tank, once again in keeping with heat exchange
principles
known in the art.
[0029] Use of a heat exchange system as described above results in energy
conservation and is thus ecological sound. The simplicity of the heat exchange
system exemplified here has several advantages. It facilitates cleaning and
maintenance of the bathing system and, in distinction to what is currently
available
commercially, is very simple to install and/or replace.
[0030] The heat exchange element 4 is conveniently shown as a plate or plate-
like
structure having a relative large surface area. The surface area and the
thickness of
the plate may be altered or otherwise designed with a view to increasing
surface area
exposure to warm shower or waste water to maximize the efficiency of the heat
exchange. While illustrated as a rectangle in Figure 1, the heat exchange
element 4
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can in practice assume any geometry that is required to fit within the shape
of a
desired bathing apparatus.
[0031] The heat exchange element 4 may be made of any heat conductive
material,
including, without limitation, any metal, concrete or stones, composites
comprising a
polymer, or a conductive material, like graphite.
[0032] Figure 2 shows an alternative version of the heat exchange system
illustrated
in Figure 1. In this version, a non-conductive material 9, shown here as a
series of
circles, is applied on the surface of the heat exchange element 4 and serves
as a
barrier between the bather and the heat exchange element. It will be
appreciated
that the shape, size, configuration and/or pattern of the non-conductive
material 9
is(are) limited only by creativity. The non-conductive material can be made of
wood,
rubber, plastic or any other synthetic material that is suitable for the
desired purpose.
It may in some instances serve the dual purpose of preventing the bather from
slipping while in the bathing apparatus.
[0033] Figure 3 shows a slightly modified version of the heat exchange system
illustrated in Figures 1 and 2. In this specific version, two small "dams" or
dam-like
elements 12 have been introduced in the bottom of the bathing apparatus in the
vicinity of the drain 8 in order to control water flow through the controlled
opening 14.
Warm shower or waste water remains in contact with the heat exchange element 4
for a longer duration than in the absence of the dams 12, which enhances heat
transfer from the water to the heat exchange element.
[0034] A number of dams or dam-like elements 12 can be introduced into a
bathing
apparatus 2 so as to create one, or more than one, controlled opening(s) 14.
This
allows the discharge of warm waste water to be controlled, and therefore
allows
modulation of the effective heat transfer. The dams or dam-like elements 12
may be
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integral to the bathing apparatus 2 or added to said bathing apparatus as
separate
elements thereto.
[0035] Figure 4 is yet another modified version of the heat exchange system
illustrated in Figures 1-3. This version combines the dams or dam-like
elements 12
of the heat exchange system of Figure 3 with the non-conductive material 9 of
Figure
2.
[0036] Turning now to Figures 5 to 8, an alternative embodiment of the
invention is
presented. As illustrated in Figure 5, this embodiment consists of a heat
exchange
system 20 comprising a bathing apparatus 22, a heat exchange element 24 and a
cover 29. This cover is positioned over the heat exchange element and serves
to
enclose the bathing apparatus 22. A drain 28 is included in the base of the
bathing
apparatus to allow the warm shower or waste water to leave the system. The
heat
exchange element optionally includes one or more spacers 25, as illustrated in
Figures 5 to 8. The spacers create a distance between the heat exchange
element
and the cover 29.
[0037] The cover 29 is made of any non-conductive material. Suitable non-
conductive materials include, without limitation, plastic, composite
materials, wood or
wood-like materials or materials including wood (which may optionally be
imbibed
with a preservative, such as Accoya or a resin-impregnated material), bamboo,
organic materials, glass or ceramic . The cover 29 may optionally include
openings
or the equivalent thereof to enhance water flow from the cover's surface to
the
25 heat exchange element 24. These openings 30 are also used to assist in the
lifting
of the cover from the bathing apparatus for cleaning or maintenance purposes.
[0038] Figure 6 shows a slightly different embodiment from that appearing in
Figure 5
wherein two "dams" or dam-like elements 32, similar to those in Figures 3 and
4,
30 have been included to control water flow to the drain. A controlled opening
(not
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shown) analogous to that in Figures 3 and 4 serves to delay flow of the shower
and
waste water towards the drain.
[0039] Figure 7 shows another variation of the heat exchange systems
illustrated in
Figures 5 and 6. In this version, a series of discontinuous dividers 34, or
the
equivalent thereof, have been included within the bathing apparatus 22. The
purpose of these discontinuous dividers 34 is to keep warm shower and waste
water
within the confines of the bathing apparatus for a longer time in order to
enhance
heat transfer to the heat exchange element 24. The buoys or equivalent thereof
may
be an integral part of the bathing apparatus 24 (i.e., cast at the same time
as the
bathing apparatus itself) or otherwise attached as a separate element to the
bathing
apparatus.
[0040] Figure 8 shows yet another variation of the heat exchange systems shown
in
Figures 5 and 6.. This variation is very similar to that shown in Figure 7,
but includes
a water channel 36 that surrounds the opening of the bathing apparatus 22
where the
heat exchange element 24 is positioned. Warm shower or waste water accumulates
in this channel 36 in proximity to the heat exchange element 24. As a result,
the
warm shower or waste water remains in contact with the heat exchange element
for a
longer time, enhancing heat transfer and thereby increase the overall
efficiency of the
heat exchange system.
[0041] Figures 9 and 10 show a third embodiment of the heat exchange system of
the
present invention. In this embodiment, the heat exchange system 50 comprises a
bathing apparatus 54 that is made of a conductive material. The bathing
apparatus
is the heat exchange element in this particular embodiment. The bathing
apparatus
54 may be comprised of one or more elements, wherein each element is made of a
conductive material. As shown in Figure 9, a surface 56 is made of the same
conductive material as the bathing apparatus 54, or of a different conductive
material,
but is fully attached to the bathing apparatus. This surface 56 is optionally
covered,
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partially or totally, with a non-conductive material. A gasket or other
sealing means
may be optionally included in order to ensure that the bathing apparatus is
water-
tight.
[0042] In the variation of this embodiment of the invention shown in Figure
10, a
surface 57 is made of a non-conductive material. This surface 57 is removable
from
the bathing apparatus 54 and is made of a non-conductive material, or of a
conductive material that is partialiy or totally covered with a non-conductive
material.
[0043] As shown in Figure 9, the heat exchange system 50 further includes a
drain
58. Alternatively, as shown in Figure 10, water from the shower may flow in a
channel 59 running between the surface 57 and the bathing apparatus 54. The
drain
58 is located beneath the surface in this version of the embodiment of the
invention.
[0044] Figure 11 shows a fourth embodiment of the heat exchange system of the
present invention. In this embodiment, the heat exchange system 70 comprises a
bathing apparatus 72 and one or more heat exchange elements 74. The top of the
bathing apparatus 76 may be fully integrated with its base, or optionally, a
separate
cover. The heat exchange elements are not flat like those in the other
embodiments
of the invention but consist of rectangles whose width, height and length can
be
modified so as to increase effective surface area and hence promote heat
exchange.
This embodiment may offer a solution that is more suitable to the styles of
certain
baths and showers.
[0045] As with the embodiment shown in Figures 9 and 10, the embodiment of the
invention shown in Figure 11 comprises a cover 76 made of a non-conductive
material. This cover can include an opening 78 that is positioned either in
the cover
76 or in the bathing apparatus 72. Once again, this opening facilitates access
to the
system for cleaning and maintenance purposes.
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[0046] In any embodiment, the heat exchanger is part of the bathing apparatus
and
the entire assembly is water tight.
[0047] The embodiments of the invention all have the advantage of simplicity.
Installing a heat exchange system as described above can be conveniently done
in
an existing bathing system or in a new one. Features of the invention, such as
the
limited number of components and their ability to be removed from each other
in a
relatively easy manner, allowing for ready cleaning, maintenance and
replacement.
[0048] In addition, the selection of embodiments allows for even greater
flexibility.
Depending on the style and function of the bathing apparatus, a heat exchange
system can be selected to best accomplish heat exchange.
[0049] The above-described embodiments of the invention are intended to be
examples only. Variations, alterations and modifications can be made to the
particular embodiments described herein by those of skill in the art without
departing
from the scope of the invention, as defined in the appended claims.
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