U.S. patent application number 14/126559 was filed with the patent office on 2014-08-28 for heat exchanger, shower tray and method for producing a shower tray.
This patent application is currently assigned to JOULIA AG. The applicant listed for this patent is Marcel Aeschlimann, Christopher Rast, Christoph Rusch, Reto Schmid, Martin Sigrist. Invention is credited to Marcel Aeschlimann, Christopher Rast, Christoph Rusch, Reto Schmid, Martin Sigrist.
Application Number | 20140237714 14/126559 |
Document ID | / |
Family ID | 46320718 |
Filed Date | 2014-08-28 |
United States Patent
Application |
20140237714 |
Kind Code |
A1 |
Rusch; Christoph ; et
al. |
August 28, 2014 |
HEAT EXCHANGER, SHOWER TRAY AND METHOD FOR PRODUCING A SHOWER
TRAY
Abstract
A shower tray having a heat exchanger that is arranged beneath
the shower tray for recovering heat from waste water in order to
heat up clean water, wherein a first heat-exchanger surface is in
contact with the waste water and a second heat-exchanger surface is
in contact with the clean water, and the first heat-exchanger
surface forms the floor, or part of the floor, of the shower tray.
The shower tray here is produced from one metal material and, in
the region of the tray floor, beneath the shower tray, a base plate
made of some other metal is fastened on the tray floor, so as to
form a heat-conducting connection to the tray floor is formed
substantially over the entire surface of the base plate. Beneath
the base plate, tubes are connected to the base plate in an
integral manner. The tubes form the second heat-exchanging
surface.
Inventors: |
Rusch; Christoph; (Nidau,
CH) ; Aeschlimann; Marcel; (Ligerz, CH) ;
Rast; Christopher; (Gunten, CH) ; Schmid; Reto;
(Bern, CH) ; Sigrist; Martin; (Bern, CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rusch; Christoph
Aeschlimann; Marcel
Rast; Christopher
Schmid; Reto
Sigrist; Martin |
Nidau
Ligerz
Gunten
Bern
Bern |
|
CH
CH
CH
CH
CH |
|
|
Assignee: |
JOULIA AG
Biel
CH
|
Family ID: |
46320718 |
Appl. No.: |
14/126559 |
Filed: |
June 7, 2012 |
PCT Filed: |
June 7, 2012 |
PCT NO: |
PCT/CH2012/000127 |
371 Date: |
March 26, 2014 |
Current U.S.
Class: |
4/598 ; 156/278;
205/207 |
Current CPC
Class: |
A47K 3/40 20130101; F28D
7/082 20130101; F28F 2275/025 20130101; C25D 11/04 20130101; F28F
1/00 20130101; C25D 7/00 20130101; F28D 21/0012 20130101 |
Class at
Publication: |
4/598 ; 205/207;
156/278 |
International
Class: |
A47K 3/40 20060101
A47K003/40; C25D 7/00 20060101 C25D007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 17, 2011 |
CH |
1034/11 |
Jan 11, 2012 |
CH |
59/12 |
Claims
1. A shower tray with a heat exchanger, wherein the heat exchanger
is arranged below the shower tray for a heat recovery from waste
water for heating fresh water, wherein a first heat exchanger
surface is in contact with the waste water and a second heat
exchanger surface is in contact with the fresh water, and the first
heat exchanger surface forms the base or a part of the base of the
shower tray, wherein the shower tray is manufactured of aluminium
or an aluminium alloy.
2. The shower tray according to claim 1, wherein the second heat
exchanger surface is formed by pipes or by one or more plates,
which are connected by way of a material-fit connection to the base
of the shower tray.
3. The shower tray according to claim 2, wherein the pipes are
composite pipes with an outer layer of aluminium or an aluminium
alloy and with an inner layer of copper or a copper alloy.
4. The shower tray according to claim 3, wherein the shower tray
and the outer side of the pipes are anodised.
5. The shower tray according to claim 4, wherein an edge region of
the shower tray comprises a reinforced coating, in particular a
layer produced by powder coating with aluminium oxide, or a paint
layer.
6. The shower tray according to claim 2, wherein the pipes are
welded to the base of the shower tray by way of welding spots
produced by way of laser welding.
7. The shower tray according to claim 6, wherein the welding spots
in each case have a contact region between the pipe and the base,
with a diameter of less than 2 mm and/or a distance between the
middle points of the welding spots in the region between 1.5 mm and
2.5 mm, in particular at 2 mm.
8. The shower tray according to claim 1, wherein the shower tray is
shaped by a forming process, in particular by way of deep-drawing
or by way of hydroforming or by way of superplastic
deformation.
9. The shower tray according to claim 1, with a cover, wherein the
shower tray comprises: a first edge and a second edge of the shower
tray, wherein the first and the second edge lie opposite one
another, and wherein an inclined support region for supporting the
cover is present at the first edge, and an undercut edge region is
present at the second edge of the shower tray which lies opposite
the first edge.
10. The shower tray according to claim 1, comprising reinforcement
profiles which are arranged on the lower side of the base of the
shower tray, said profiles having a U-shape with arms that are
fixedly connected to the lower side of the base of the shower tray
and through which profile one or more of the pipes lead.
11. A method for manufacturing a shower tray, comprising the steps
of shaping an aluminium blank by way of a forming process into the
shape of the shower tray; welding or soldering pipes, which at
least at their outer side consist of aluminium or an aluminium
alloy, onto the lower side of the tray base of the shower tray;
anodising the shower tray and the pipes.
12. The method for manufacturing a shower tray according to claim
11, comprising the further steps of: connecting the pipes to
manifolds, or to transition pipes into manifolds, in regions of
connections between the pipes and the manifolds or transition
pipes, manufacturing an electrical insulation layer on the outer
side of these regions.
13. The method for manufacturing a shower tray according to claim
11, wherein the method is carried out repeatedly and thereby shower
trays with differently far extended, outer edge regions are
manufactured, wherein such outer edge regions connect to edge
regions of a recess of the shower tray.
14. A shower tray with a heat exchanger, wherein the heat exchanger
is arranged below the shower tray for a heat recovery from waste
water for heating fresh water, wherein a first heat exchanger
surface is in contact with the waste water, and a second heat
exchanger surface is in contact with the fresh water, and the first
heat exchanger surface forms the tray base or a part of the tray
base, wherein the shower tray is manufactured of a steel alloy, and
a base plate of a metal that is different from the steel alloy is
fastened in the region of the tray base below the shower tray, to
the tray base, and a thermally conductive connection to the tray
base is formed by way of this essentially over the complete surface
of the base plate, and in turn pipes, below this base plate, are
connected to the base plate by way of a material-fit connection, in
particular by way of welding or soldering, and these said pipes
form the second heat exchanger surface.
15. The shower tray according to claim 14, wherein the base plate
is fastened by way of welding or adhesive bonding on the lower side
of the tray base.
16. The shower tray according to claim 15, wherein adhesive bonding
is accomplished via an adhesive layer provided by an adhesive
film.
17. The shower tray according to claim 16, wherein the adhesive
film has added aggregates or is strewn with aggregates, for
improving its thermal conductivity.
18. The shower tray according to claim 15, wherein adhesive bonding
is accomplished by an an epoxy resin that includes added aggregates
for improving its thermal conductivity.
19. The shower tray according to claim 14, wherein the metal of the
base plate and the metal of the pipes is copper or a copper
alloy.
20. The shower tray according to claim 14, in which wherein the
metal of the base plate and the metal of the pipes at least on the
outer side of the pipes is aluminium or an aluminium alloy.
21. The shower tray according to claim 20, wherein the pipes are
composite pipes with an outer layer of aluminium or an aluminium
alloy and with an inner layer of copper or a copper alloy.
22. The shower tray according to claim 14, wherein the shower tray
on the upper side is provided with an enamel layer, is not
enamelled on the lower side, and comprises ribs on the lower side,
said ribs providing for mechanical stabilisation of the shape of
the tray base.
23. A shower tray according to claim 22, in which the enamel layer
has added metal particles that improve thermal conductivity of the
enamel layer.
24. The shower tray according to claim 23, wherein the metal
particles are of stainless steel and are rust-free, in particular
of CrNi steel.
25. A method for manufacturing a shower tray, comprising the steps
shaping a steel blank by way of a forming process, into the shape
of the shower tray; fastening, in particular welding or soldering
on ribs, for the stabilisation of the shape of a tray base of the
shower tray, enamelling the shower tray; bonding a base plate with
pipes attached thereon, onto the lower side of the tray base, or
bonding the base plate onto the lower side of the tray base and
subsequently attaching the pipes to the base plate.
26. The method for manufacturing a shower tray according to claim
25, comprising the following steps for enamelling the shower tray:
enamelling the shower tray with the ribs, and, by way of this,
forming an enamel layer on the lower side of the tray base;
removing the enamel layer on the lower side of the tray base.
27. A semifinished product for manufacturing a shower tray
according to claim 11, comprising a plane base plate with pipes
which are welded thereon, wherein the base plate essentially has a
rectangular contour, and the pipes are arranged outside this
contour for connection of manifolds.
28. The semi-finished product according to claim 27, wherein the
base plate comprises cut-outs for receiving ribs of the shower
tray.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to heat exchangers
and, more particularly, to a shower tray as well as to a method for
manufacturing a shower tray.
[0003] 2. Description of Related Art
[0004] Such a shower tray is known, for example, from WO
2010/088784 A1 of the same applicant. The heat exchanger comprises
a plane cover plate as a run-off surface, over which waste water
runs off The cover plate is formed from chrome steel, forms the
base of the shower tray and can be integrally formed with the
shower tray. The plate either consists of two layers, of which the
one is profiled and is placed below the other, by which means
meandering channels are defined between the plates, or pipes
through which water to be heated flows, are soldered against a
plate.
[0005] DE 44 06 971 shows a shower tray, on whose lower side
channels, through which cold water flows, are attached by way of
welding on pipes (tubes) or profiles.
[0006] NL 1031082 shows a heat exchanger below a shower tray, with
which pipes are soldered via a narrow web onto a run-off
surface.
[0007] WO 2009/030503 describes the manufacture of thermal solar
collectors, with which heat fluid pipes are welded onto an absorber
plate with a laser.
[0008] GB2420973 shows a shower tray with a heat exchanger with an
undercut tray wall, into which an elastic region of an insertable
tray base snaps. In another embodiment, a further undercut region
of the tray edge can cooperate with projections of the tray base,
in order with a rotation of the tray base, to lock or release
this.
[0009] As a whole, the construction height is too high and the
cleaning too difficult with existing heat exchangers of this type.
The cleaning is also technically relevant, since the cleanliness of
the heat exchanger has a large influence on the efficiency of the
heat exchanger. Moreover, the manufacture is complicated and the
material weight very large.
SUMMARY OF THE INVENTION
[0010] It is therefore the object of the invention, to create a
shower tray of the initially mentioned type that has a
comparatively small construction height and is simple to clean. A
further object is to provide a suitable manufacturing method for
such a shower tray.
[0011] According to a first aspect of the invention, thus a shower
tray with a heat exchanger is present, wherein the heat exchanger
is arranged below the shower tray for a heat recovery from waste
water, for heating fresh water, wherein a first heat exchanger
surface is in contact with the waste water, and a second heat
exchanger surface is in contact with the fresh water, and the first
heat exchanger surface forms the base or a part of the base of the
shower tray. Thereby, the shower tray is manufactured of aluminium
or of an aluminium alloy. Metal alloys which have a weight
component of at least 80% aluminium are considered as aluminium
alloys. Hereinafter, when one speaks of aluminium, this is also to
be understood as an aluminium alloy. It is also possible to
manufacture the tray from a metal with a thermal conductivity of
above 100 W/(mk).
[0012] In one embodiment, the second heat exchanger surface is
formed by pipes (tubes), which are connected to the base of the
shower tray by way of a material-fit connection, in particular
welding or soldering
[0013] In further embodiments, instead of pipes, intermediate
spaces are present between the base and one or more plates, for
example of metal. Thereby, the intermediate spaces form channels
for leading the fresh water, as described in the already mentioned
WO 2010/088784, which is herewith included by way of reference, in
particular with its FIGS. 2-6 and 9 and the respective description
parts.
[0014] It is the case with all embodiments: in order to effect a
good heat transfer, a turbulent flow should be present in the pipes
or the channels. For this reason, the inner diameter of the pipes
is kept small, or the inner side of the pipes is profiled, which
for example can also be effected by way of deforming the pipes from
the outside. The flow resistance of the pipes increases by way of
such measures, which is why several pipes are led in parallel.
Thereby, the length of the pipes is essentially the same.
[0015] In one embodiment, the pipes are composite pipes (or dual
pipes) with an outer layer of aluminium or of an aluminium alloy
and with an inner layer of copper or a copper alloy. Copper alloys
which have a weight component of at least 50% copper are considered
as copper alloys. Hereinafter, a copper alloy is also meant when
one speaks of copper.
[0016] In another embodiment, a copper pipe is welded onto the tray
base of aluminium, in particular by way of laser welding. For this,
a weldable anodising layer is formed on the tray base preferably
beforehand.
[0017] In one embodiment, the shower tray and the outer side of the
pipes are anodised. The pipes are closed with a cap, for example,
during the anodisation, so that the copper layer in the pipes is
not dissolved by the anodisation bath. Preferably, the anodising is
effected after the welding, by which means the welding procedure is
simplified. The other way round however would make the connection
of the pipes to connection elements of copper after the anodising
more complicated, since the occurrence of a galvanic element is to
be prevented.
[0018] In one embodiment, an edge region of the shower tray
comprises a further or a reinforced coating, in particular a layer
produced by powder coating, for example with aluminium oxide, or
paint layer. An increased abrasion resistance can be achieved in
the edge region by way of this.
[0019] In one embodiment, the complete shower tray comprises a
coating that permits a corrosion protection or wear protection,
and/or a wetting of the surface (hydrophilic coating).
[0020] In another embodiment, the shower tray is shaped by way of a
forming process, in particular by way of deep-drawing or
hydroforming or by way of superplastic deformation. It can
additionally also be formed by bending and welding individual
sections of the shower tray.
[0021] The use of aluminium as a base material leads to a series of
advantageous that synergistically complement one another and that
improve the efficiency and the manufacturability. [0022] The
connection by way of soldering or welding can be designed more
simply by way of the same material being used for the tray base and
the pipes. A laser welding of a good quality is particularly
possible. The quality and service life of the device are improved
by way of this. [0023] The thermal conductivity of aluminium of
comparatively high, which improves the efficiency. [0024] The
anodic passivation of aluminium--in contrast to a coating with
paint or enamel--leads to a hydrophilic, thin protective layer with
a good heat transfer, which improves the efficiency. [0025]
Aluminium pipes in the field of sanitation can also be used due to
the use of composite pipes with an inner coating or an inner casing
of copper. Due to the fact that these pipes at the outside are of
aluminium, they can be connected to the tray base of aluminium,
before both are anodised together. If the pipes were not of
aluminium, the tray base would have to be anodised already before
the connection to the pipes, which in turn renders the welding more
difficult. [0026] Aluminium can be formed better than steel. With
this, the run-off region can be designed in a narrower manner, by
which means the active surface of the heat exchanger becomes larger
than is possible for example with a steel tray of a similar shape.
An improvement of the efficiency also takes place with this. [0027]
Moreover, sharper contours in the four corners of the shower tray
can be shaped, so that according to one embodiment, no cutting and
welding or no further elements as "gap fillers" are necessary for
the installation. [0028] Aluminium is more than 3 times lighter
than copper and somewhat less than 3 times lighter than steel, and
this leads to a very significant saving of weight for the transport
to the building or installation site and also additionally
simplifies the installation for the precise positioning of the
tray.
[0029] The combination of hydroforming for shaping the tray, and
anodising as a surface treatment is advantageous: drawing traces on
the upper side of the tray which arise with normal forming with a
male and female die, would have to be subsequently treated or be
laminated by a material-depositing method (coating, painting).
Essentially no such drawing marks arise on hydroforming a tray (or
not in a region where they disturb), and thus an anodisation can
take place, without the trough surface having to be subjected to
post-treatment.
[0030] On forming, in particular by way of hydroforming, different
variants of shower trays can be manufactured in the same shape.
These variants have the same shape of the recess with the shower
base and the heat exchanger, but differently large outer edge
regions as standing surfaces around these. A set of shower trays
having different variants can be manufactured in this manner.
[0031] A further advantage of the manufacture by way of
hydroforming is that undercut portions can be shaped in a
particularly simple manner, thus without the use of slides.
[0032] In one embodiment, the shower tray comprises a cover (lid),
and moreover a first edge and a second edge, wherein the first and
the second edge lie opposite one another, and wherein an inclined
support region for supporting the cover is present on the first
edge, and an undercut edge region is present on the second edge of
the shower tray which lies opposite the first edge. The cover due
to the inclination in the support region is pressed into the
undercut region when loaded. Preferably, no undercut regions are
present in the support region, and the cover can be lifted upwards
without further ado. In contrast, in the undercut region, the cover
cannot be lifted without previously pulling the cover in the
horizontal direction towards the second edge, out of the undercut
region.
[0033] In one embodiment, reinforcement profiles are arranged on
the lower side of the shower tray. The shower tray can be designed
thinner and lighter by way of this. The reinforcement profiles can
be welded to the shower tray or bonded to this. The reinforcement
profiles can have a U-profile and thus encompass or bridge one or
more of the pipes. This necessitates the reinforcement profiles
being attached on the shower tray after attaching the pipes.
[0034] Preferably, the following steps are carried out for
manufacturing a shower tray: [0035] shaping an aluminium blank by
way of a forming process, into the shape of the shower tray, in
particular by way of hydroforming; [0036] optionally: forming, in
particular bending, and welding individual sections of the blank;
[0037] welding on or soldering on pipes which at least on their
outer side consist of aluminium, onto the lower side of a tray
base; [0038] coating surfaces or the complete outer surface and/or
anodising the shower tray and the pipes (wherein the pipe ends are
preferably covered on anodising, above all if the pipes of
aluminium comprise a layer of copper on the inner side); [0039]
optionally, attaching the reinforcement profiles;
[0040] The method in one embodiment can comprise the further steps:
[0041] connecting the pipes onto manifolds or onto transition pipes
into manifolds, of a metal that is different to the outer material
of the pipes; [0042] in regions of connections between the pipes
and the manifolds or transition pipes, manufacturing an electrical
insulation layer on the outer side of these regions.
[0043] This insulation layer prevents a flow of charge carriers in
the region between the outer layer of the pipes (for example
aluminium) and the manifolds or transition pipes (for example of a
copper alloy) and the formation of a galvanic element in the case
that this region should become contaminated and/or moist. The
transition pipes, for example, are of copper. The insulation layer,
for example, is formed by a shrink hose or by a coating in the
region of the connection between the manifolds or transition pipes
and a section of the pipes or their outer (aluminium) layer.
[0044] The method for manufacturing a shower tray, in particular
with the use of hydroforming, can be carried out in a repeated
manner, wherein shower trays with outer edge regions extended to a
differently far extent are manufactured, wherein such outer edge
regions connect to edge regions of a recess of the shower tray.
These outer edge regions form a standing surface after the
installation of the shower tray. Thus shower trays for showers with
differently large standing surfaces can be manufactured with the
same forming tool.
[0045] According to a second aspect of the invention, thus a shower
tray with a heat exchanger is present, wherein the heat exchanger
is arranged below the shower tray for a heat recovery from waste
water for heating fresh water, wherein a first heat exchanger
surface is in contact with the waste water and a second heat
exchanger surface is in contact with the fresh water, and the first
heat exchanger forms the tray base or a part of the tray base.
Thereby, the shower tray is manufactured of a steel alloy, and a
base pate, also called sheet plate or heat exchanger plate, of a
different material is fastened in the region of the tray base below
the shower tray, on the tray base, by which means a thermally
conductive connection to the tray base is formed essentially over
the compete surface of the base plate. Again, pipes are connected
to this base plate by way of a material-fit connection, below this
base plate, in particular by way of welding or soldering, wherein
these pipes form the second heat exchanger surface.
[0046] Preferably, the heat exchanger plate is fastened on the
lower side of the tray base by way of a fixed connection,
preferably by way of a bonding or welding method, for example with
a bonding film or by way of an epoxy resin. The welding method can
be friction welding. The epoxy resin can have added aggregates for
increasing its thermal conductivity.
[0047] In one embodiment, the shower tray comprises an enamel layer
on the upper side, and is not enamelled on the lower side, wherein
ribs for the mechanical stabilisation of the shape of the tray base
are arranged on the lower side. These ribs for example are about 10
mm high and stabilise the tray base during the enamelling: they
prevent a warping, which would bulge out the tray base to the top
or to the bottom, whereupon the waste water would no longer run off
over the tray base in a uniform manner.
[0048] In one embodiment, the enamel layer has added aggregates
(additives) for improving its thermal conductivity, in particular
added metal particles. These, for example, are rust-free of
stainless steel (also called Inox), in particular CrNi steel.
Although such steels seen per se are poor heat conductors, as
aggregates on enamelling they surprisingly lead to an improvement
of the thermal conductivity of the enamel.
[0049] Such an enamel layer can also be applied independently of
the application of the heat exchanger, for example, for coating
cooking utensils. According to a further aspect of the invention,
an enamel layer is created that has a comparatively high thermal
conductivity.
[0050] The shower tray according to the first aspect of the
invention can be understood and realised completely independently
of a shower tray according to the second aspect of the
invention.
[0051] Individual elements of the first or second aspect however,
where technically realisable, can be transferred to the respective
other aspect, and produce the same effect there.
[0052] The method for manufacturing a shower tray of a steel alloy
comprises the following steps [0053] shaping a steel blank by way
of forming process, into the shape of the shower tray; [0054]
optionally: forming, in particular bending, and welding individual
sections of the blank; [0055] fastening, in particular welding on
or soldering on ribs for stabilising the shape of the tray base;
[0056] enamelling the shower tray; [0057] bonding a base plate with
pipes attached thereto, onto the lower side of the tray base, or
bonding the base plate onto the lower side of the tray base and
subsequent attachment of the pipes on the base plate.
[0058] Preferably, the ribs are coated, in particular by way of
painting, in a further step for the corrosion protection.
[0059] According to one embodiment of the invention, the following
steps are carried out for enamelling the shower tray [0060]
enamelling the shower tray with the ribs, and the formation of an
enamel layer by way of this; [0061] removing the enamel layer on
the lower side of the tray base; for example, by sand blasting.
[0062] One avoids the lower side being coated at a high temperature
with a thick scale layer, by way of the lower side (with the ribs)
also being enamelled.
[0063] According to an alternative embodiment of the invention, the
following steps are carried out for enamelling the shower tray:
[0064] enamelling only the upper side of the shower tray (thus the
surface lying opposite the ribs), and further regions of the shower
tray, but not the surface onto which the base plate is to be
bonded; [0065] possibly machining the lower side of the tray base
for removing the scaled layer; for example, by way of sand
blasting.
[0066] According to a further aspect of the invention, a
semifinished product for manufacturing the shower tray is created.
This comprises a plane base plate with pipes welded thereon.
[0067] In one embodiment, the base plate comprises cut-outs for
leading through ribs of the shower tray.
[0068] With both aspects of the invention, thus with the shower
tray as well as with the semifinished product, the heat exchanger
for example has a width of between 50 cm and 150 cm and a length
between 50 cm and 150 cm. The width and length according to one
embodiment are at least approximately equal to 75 cm.
[0069] The term "shower tray" in this application is understood to
comprise the term "bath tub". In a further embodiment, the shower
tray is thus a bath tub. In this case, the heat exchanger for
example has a width of between 20 cm and 70 cm and a length between
80 cm and 200 cm.
[0070] A pipe distance between the pipes of the heat exchanger
which run in parallel is 1 cm to 5 cm or 2 cm to 5 cm, in
particular at least approximately 2.4 cm (measured from pipe middle
to pipe middle), in the embodiments of both aspects of the
invention. In contrast to pipes of heat exchanger in solar
collectors, where greater temperature gradients are present, the
pipe distance in particular is smaller than 7 cm. Moreover,
likewise in contrast to pipes of heat exchangers in solar
collectors, for example the distances between welding spots are
also about 2 mm (from middle to middle of the welding spots),
wherein for example the welding spots themselves have a diameter of
less than 2 mm, and the pipe diameters are smaller, i.e. with inner
diameters of between 4 mm and 10 mm, in particular 4.75 mm.
[0071] In the embodiments of both aspects of the invention,
manifolds, to which the pipes are connected, are arranged outside
the run-off surface. In this manner it is possible for an as large
as possible surface of the run-off surface to act as a heat
exchanger.
[0072] In embodiments of both aspects of the invention, the
gradient of the tray base for example is between 3% and 4.5%, in
particular 3.5%. This applies to the tray base in the assembled
condition. This therefore also applies to the angle between the
upper edges of the tray and the tray base, amid the assumption that
the edges of the tray are to be assembled horizontally. A
particularly good heat transfer results with this gradient,
unexpectedly better than with a smaller angle, such as 2% for
example.
[0073] Further preferred embodiments are to be deduced from the
dependent patent claims. Thereby, features of the method claims
according to context can are combinable with the device claims and
vice versa.
BRIEF DESCRIPTION OF THE DRAWINGS
[0074] The subject-matter of the invention is explained in more
detail hereinafter by way of preferred embodiment examples which
are represented in the accompanying drawings. In each case
schematically are shown in:
[0075] FIG. 1 a shower tray in a first embodiment;
[0076] FIG. 2 a shower tray in a second embodiment;
[0077] FIG. 3 a cross section of the construction of a heat
exchanger with a shower tray of aluminium
[0078] FIGS. 4 and 5 cross sections of the construction of a heat
exchanger with a shower tray of steel;
[0079] FIG. 6 a shower tray with a projection for the arrangement
of a run-off;
[0080] FIG. 7 a base plate with heat exchanger pipes;
[0081] FIGS. 8 and 9 a shower tray in a third embodiment;
[0082] FIG. 10 variants of edge regions to a shower tray; and
[0083] FIG. 11 a shower tray with an undercut edge region.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0084] The reference numerals applied in the drawings and their
significance are listed conclusively in the list of reference
numerals. Basically, the same parts are provided with the same
reference numerals in the figures.
[0085] FIG. 1 shows a shower tray 10 in a first embodiment in an
exploded drawing. The shower tray 10 is designed as a heat
exchanger 1, by way of a tray base 12, over which waste water flows
during showering, being connected in a thermally conductive manner
to pipes 14, through which fresh water is led. The pipes 14 for
this extend over an as large as possible part of the tray base 12.
The fresh water is fed to the pipes 14 through a feed conduit 22
and a first manifold 21, and there is distributed to several (two,
three, four, five, six or more) parallel pipes 14, flows in the
counter direction to the waste water or in the same direction
through meandering pipes 14 to a second manifold 21. Thereby, the
pipes 14 are led to one another in an essentially equidistant
manner, by which means a balanced heat transfer over the surface
takes place. In the shown embodiment, the pipes 14 are distanced to
one another in the region, in which they run transversely to the
gradient of the tray base 12, as well as in the region, in which
they run parallel to the gradient. The distance of the pipes 14 is
between 20 mm and 30 mm, for example 24 mm (measured from middle to
middle). The sections of the individual pipes 14 between the
manifolds 21 are all equally long, so that their flow resistance
and thus also their flow is essentially the same. Transition pipes
20 can be arranged at the transition between pipes 14 and manifolds
21 for reasons of manufacturing technology. On operation of the
shower, the waste water flow over a slightly inclined cover 4 to
one side of the shower tray 10 to a run-in region 33, and from this
in turn, in a manner distributed over the width of the tray base
12, over the tray base 12 to a run-off region 34 and from there to
a run-off 35. An edge region 32, which is preferably led around the
shower tray 10, is designed obliquely with an angle of between
about 40.degree. to 70.degree.. Height-adjustable feet 132 can be
present for setting the level of the shower tray 10 on
installation. The cover 4 is designed with a corresponding
inclination at its cover edge 342. The edge region 32 on account of
this forms a seat that is trapezoidal in cross section, for a cover
4, and centres this cover in the shower tray 10.
[0086] FIG. 2 shows a shower tray in a second embodiment in an
exploded drawing. With regard to the function, the same elements
are present in a somewhat different design than with FIG. 1.
Additionally present: the tray base 12 comprises webs or ribs 31
for reinforcement. A sheet-metal plate, hereinafter called base
plate, 13 is arranged between the tray base 12 and the pipes 14.
This base plate 13 comprises cut-outs 23 that correspond to the
position of the ribs 31, i.e. are cut-out in each case in the
region of a rib 31, so that the base plate 13 can be fastened
flatly onto the lower side of the tray base 12. Bent-down or
integrally formed side walls 37 can be present at the edge of the
shower tray 10.
[0087] FIG. 3 shows a cross section of the construction of a heat
exchanger with a shower tray 10 of aluminium, as a rule an
aluminium alloy. The shower tray is preferably manufactured as one
piece by way of a forming process, in particular inner high
pressure forming (hydroforming), and/or by way of cutting, bending
and welding, and thus the tray base 12 is also of this material.
Warm waste water 145 flows over the tray base 12 in operation.
Beneath the tray base 12, pipes 14 with fresh water 144, for
example in an arrangement according to FIG. 1 or 2, are welded in
particular by way of laser welding, or soldered, directly against
the lower side of the tray base 12. Contact regions of soldering
locations or welding spots 143 thereby have a diameter d of
preferably less than 2 mm. The distance between welding spots 143,
for example, is at least approximately 1 mm (along the direction of
the pipe). In one embodiment, the distance of the welding spots
lies in the region between 1.5 mm and 2.5 mm, in particular at 2 mm
(in each case measured from the middle of a welding spot up to the
middle of the next welding spot). An improved heat transfer results
with this. A greater distance worsens the efficiency of the heat
exchanger and smaller distance does not improve it significantly.
The diameter of a welding spot is thereby preferably smaller than 2
mm, in particular approx 1 mm
[0088] In one embodiment, the pipes 14 are manufactured of
aluminium or of an aluminium alloy. Preferably they are moreover
coated on the inner side, for example with polyethylene (PE). In
another embodiment, the pipes 14 are composite pipes (bimetal
pipes, composite pipes, dual pipes) with an outer wall or an outer
layer 141 of aluminium or of an aluminium alloy and with an inner
wall or inner layer 142 of copper or a copper alloy, for example of
copper deoxidised by phosphorous (Cu-DHP). Exemplarily applied
composite pipes have a wall thickness of approx. 0.55 mm aluminium
(alloy) and 0.25 mm copper (alloy) with an outer diameter of
approx. 6.5 mm (1/4'' inch; 6.35 mm) The inner diameter is thereby
approx. 4.75 mm.
[0089] The shower tray 10 and thus also the tray base 12 and the
pipes 14 are preferably anodised (eloxised), in particular
hard-anodised, and by way of this are wear-resistant and at the
same time thermally conductive. The edge of the tray that is
visible next to the cover 14, additionally to the anodising, can be
coated or painted in a different colour. Alternatively to
anodising, the tray base 12 can be painted at least on the waste
water side, thus the upper side, preferably with a hydrophilic
paint.
[0090] On anodising the composite pipes 14, these are closed at the
ends when manufacturing the shower tray 10, so that the inner layer
of copper is not dissolved in the anodising bath.
[0091] FIG. 10 schematically shows shower trays 10 with different
variants of outer edge regions 36. Such variants are manufacturable
in the same shape by way of forming, in particular hydroforming The
shape of the recess of the tray with the tray base 12 and the heat
exchanger 1 is the same with this variant, and an outer edge region
16 connecting to the recess is designed in a manner extending
differently far in one or more directions. Given an assembled
shower tray 10, these outer edge regions 36 are essentially
horizontal and form a stepping surface. Variants can be
manufactured in this manner for example, with which the base area
is 90 cm times 90 cm (standard size), or 90 cm times 120 cm, or 90
cm times 140 cm. What are not shown are optional lateral additional
regions which are bent downwards, in order to form side walls 37
such as in the embodiment of FIGS. 8-9, for example.
[0092] In an alternative embodiment, the shower tray 10 is
rust-free of stainless steel, in particular CrNi steel, and the
pipes 14 of copper or a copper alloy are welded on. Such an
arrangement however has a reduced efficiency as a heat
exchanger.
[0093] FIG. 4 shows a cross section of the construction of a heat
exchanger with a shower tray 10 of steel, as a rule from enamelled
steel. The shower tray 10 is preferably manufactured as one piece
by a forming process and/or by cutting, bending and welding, and
thus the tray base 12 is also of this material. Warm waste water
145 flows over the tray base 12 in operation. Pipes 14 with fresh
water 144, for example in an arrangement according to FIG. 1 or 2,
are welded, in particular by laser welding, or soldered, against
the lower side of a base plate 13, below the tray base 12. Contact
regions of solder locations or welding spots 143 thereby have a
diameter d of preferably less than 2 mm. Standards for potable
water can be adhered to by way of this. The base plate 13 in turn
is bonded against the tray base 12 by way of an adhesive layer 15.
A cover layer, typically paint or enamel layer 16 is deposited on
the upper, i.e. water-water-side of the tray base 12.
[0094] The material of the base plate 13 and pipes 14 is preferably
essentially the same or of the same type, thus for example in each
case aluminium (alloy) or in each case copper (alloy). They can be
more easily connected to one another by way of this, in particular
by way of welding or soldering. In the case that the material is
aluminium or an aluminium alloy, the pipes 14 for example are
composite pipes, as described above, thus are of aluminium or an
aluminium alloy at least at the outer side of the pipes.
[0095] The adhesive or bonding layer 15 on the one hand effects a
compensation of different expansion of the tray base 12 and base
plate 13 on heating, and on the other hand the heat transfer from
the tray base 12 to the pipes 14. The bonding layer 15 according to
one variant is formed by a bonding film, i.e. by a bonding material
which is provided as a thin layer or foil, for example of a
thermoplastic material. It can have added aggregates or be strewn
with aggregates (on one or both sides), for improving its thermal
conductivity, in order to improve the thermal conductivity of the
bonding foil. Such aggregates for example are powder of a metal
(aluminium, copper, etc . . . ) or of a carbide or boride (SiC,
TiC, TiB.sub.2).
[0096] According to another variant, the adhesive layer 15 is an
epoxy resin which can likewise have added one of the mentioned
materials as an aggregate for improving the thermal conductivity.
FIG. 5 accordingly shows a variant of FIG. 4 with metal particles
151 in the bonding layer 15.
[0097] In the case that the cover layer is an enamel layer 16, then
according to one embodiment, the parent substance for the enamel
layer 16 is provided with a material for improving the thermal
conductivity before the enamelling.
[0098] According to one embodiment of the invention, this material
is a rust-free stainless steel (Inox), in particular a CrNi
steel.
[0099] Exemplary embodiments for thermally conductive enamel layers
are: [0100] Example 1: mixture of commercially available ground
enamel slip and 50% by weight of stainless steel powder Cold 100.
Result after burning-in (baking) at 850.degree. C. on a shower
tray: the layer thickness was 150 .mu.m and the surface was melted
smoothly. The adhesion according to EN 10209 Annex D was at 1. Cold
100 is a material with 19.1% Ni, 20% Cr and 6.3% Mo. [0101] Example
2: mixture of commercially available, acid-resistant direct enamel
and 30% by weigh of stainless steel powder 304 LHD. Result after
baking at 830.degree. C. on a shower tray: the layer thickness was
100 .mu.m and the surface was smoothly melted. The adhesion
according to EN 10209 Annex D was 1. 304 LHD is a material with
11.8% Ni and 19% Cr. [0102] Example 3: mixture of commercially
available titanium white [vitreous] enamel and 20% by weight of 316
LHD. The result after baking at 820 .degree. C. on a shower tray:
the layer thickness of the titanium white enamel was 150 .mu.m. The
surface was melted smoothly and slightly coloured by way of the
stainless steel particles. 316 LHD is a material with 12.7% Ni, 17%
Cr and 2.2% Mo. [0103] Example 4: mixture of commercially available
ground enamel and 70% by weight of stainless steel powder 434 LHC.
The result after baking at 850.degree. on a shower tray: the
adhesion according to EN 10209 Annex D was 2. The surface was
uniformly smooth. 434 LHC is a material with 16.8% Cr and 1.0%
Mo.
[0104] With the manufacture of the enamel layer, at least of a
ground enamel layer, the shower tray 10 must be enamelled as a
whole. Ribs 31 can be welded or soldered on below the tray base 12,
in order to prevent a deformation of the shower tray 12 at the high
temperatures (850.degree. C.) on enamelling. The lower side of the
tray base 12 is sand blasted, or the enamel layer removed in
another manner before bonding on the base plate 13 with the pipes
14. The ribs 31 finally receive a new corrosion protection in place
of the removed enamel layer.
[0105] FIG. 6 shows one embodiment, in which the run-off 35 is
arranged next to the run-off surface 17 acting as a heat exchanger.
The run-off surface 17 in particular forms a rectangle (or a circle
or an oval), and the run-off is not arranged within this
rectangular shape (or a circle or oval). Thus the complete run-off
surface 17 is available as a heat exchanger surface. Moreover, a
more regular leading of the for example meandering pipes over the
run-off surface is possible, since there is no interruption of the
rectangular (or circular or oval-shaped) surface due to the
run-off. The heat transfer is improved by way of this.
[0106] FIG. 7 accordingly shows a base plate 13 with an essentially
rectangular contour, wherein the pipes 14 are arranged essentially
outside this contour for the connection of manifolds 21
(dashed).
[0107] The run-off 35 in particular can be arranged at a projection
18 of the shower tray 10, so that the base mass of the shower tray
10 is not affected. On installation of the shower tray, for example
a suitable opening in the wall 19, for example a lightweight
construction wall, behind which conduits are led, is merely to be
provided in the region of the projection 18. The run-off region 34
is a channel or recess, which leads the waste water to the run-off
35. A projection 18 and the further features described here with
regard to the FIGS. 6 and 7 can be combined with other features of
the embodiment according to FIG. 1 as well as FIG. 2.
[0108] FIGS. 8-9 show a shower tray in a third embodiment in a plan
view and a lower view. The individual elements, inasmuch as not
described otherwise, are designed as with the embodiment of FIG. 1,
in particular with a tray of aluminium or an aluminium alloy. A
contrast with regard to FIG. 1 is the fact that the shower tray has
no pronounced run-off channel towards the run-off, but a transverse
gradient or drop, for example in the shape of a triangle. The tray
base can have a gradient of 3.5% in the main flow direction. A
further contrast to the embodiment of FIG. 1 is that here
additional reinforcement profiles 131 are present, which are
fixedly connected to the lower side of the tray base 12, in
particular by way of bonding, soldering or welding. In the shown
embodiment, the reinforcement profiles 131 for reasons of
manufacturing technology are bonded onto the lower side of the tray
base 12, for example with an epoxy adhesive. The reinforcement
profiles 131 comprise a U-profile with additional flanges that form
the connection to the tray base. The reinforcement profiles 131
each at the two ends of the two arms of the U-profile (seen in
cross section) are connected to the lower side of the tray base.
The reinforcement profiles 131 extend parallel to sections of the
pipes 14 and thereby encompass one or more of the pipes 14. The
pipes 14 thus lead through the U-profile of the reinforcement
profiles 131. The reinforcement profiles 131 stiffen the tray base
and this permit these to be designed of thinner material. Moreover,
the reinforcement profiles 131 serve as a protection of the pipes
14 from damage on the building side, for example on putting down
the heat exchanger onto an uneven surface. Connections 24 for the
feed and discharge of water to/from the heat exchanger are for
example arranged next to one another on the same side wall 37.
[0109] FIG. 11 shows a shower tray 10 with an undercut edge region
38. This lies opposite a bevelled support region 39. These two
regions form a seat for the cover 4. The edge is recessed in an
undercut manner in the undercut region 38 at a side of the shower
tray 10, seen in a in a cross sectional plane running
perpendicularly to the edge. It forms an indentation by way of
this, in which the edge of the cover 4 lies. The result of this is
that the cover 4 at this location cannot be moved perpendicularly
upwards, but for this must be firstly pulled out of the indentation
a little, in the direction of the opposite side of the tray. This
in turn, with a loading of the cover 4 on the opposite side,
prevents the cover from slipping down in the support region, being
tilted as a whole and lifted at the side with the indentation. The
support region with respect to the normal (in the assembled
condition of the tray, wherein the upper edge of the tray runs
horizontally) has an inclination between 30.degree. and 80.degree.,
in particular 45.degree. and 70.degree. and especially of
60.degree.. The cover 4 thus lies on the support region 39 and can
be lifted there without further ado. The cover 4 on loading is
pressed into the indentation due to the inclination of the support
region 39. The design of the edge regions according to FIG. 11 can
be combined with all described variants of shower tray, in
particular with this of FIG. 1, 2 and 8 or 9.
* * * * *