U.S. patent application number 11/917893 was filed with the patent office on 2009-05-07 for solar collector and mounting bracket.
This patent application is currently assigned to VKR HOLDING A/S. Invention is credited to Per Jacobsen, Brent Moller, Johnny Nygaard.
Application Number | 20090114209 11/917893 |
Document ID | / |
Family ID | 35840069 |
Filed Date | 2009-05-07 |
United States Patent
Application |
20090114209 |
Kind Code |
A1 |
Moller; Brent ; et
al. |
May 7, 2009 |
Solar Collector and Mounting Bracket
Abstract
A solar collector with a rectangular frame (1), preferably made
of extruded or rollformed metal, containing an absorber plate (3),
an insulating layer (2) beneath the absorber plate (3), and a cover
pane (4) spaced above the absorber (3). Absorber tubing (3b.3c) is
attached to the rear side of the absorber plate. The absorber (3)
is secured to the frame (1) by mounting brackets (11a,11b) that
engage the absorber tubing (3b,3c) and allow for substantially
unhindered thermal expansion and contraction of the absorber. The
collector can be integrated or roof mounted on a pitched roof, or
may be installed on a flat roof by means of a mounting frame.
Inventors: |
Moller; Brent; (Gentofte,
DK) ; Jacobsen; Per; (Horsens, DK) ; Nygaard;
Johnny; (Hedensted, DK) |
Correspondence
Address: |
CROCKETT & CROCKETT, P.C.
26020 ACERO, SUITE 200
MISSION VIEJO
CA
92691
US
|
Assignee: |
VKR HOLDING A/S
Horsholm
DK
|
Family ID: |
35840069 |
Appl. No.: |
11/917893 |
Filed: |
June 16, 2005 |
PCT Filed: |
June 16, 2005 |
PCT NO: |
PCT/EP2005/006460 |
371 Date: |
July 14, 2008 |
Current U.S.
Class: |
126/569 |
Current CPC
Class: |
F16L 3/18 20130101; F16L
3/1041 20130101; Y02E 10/44 20130101; F24S 25/00 20180501; F24S
2025/011 20180501; F24S 40/80 20180501; F24S 80/40 20180501; Y02B
10/20 20130101; F16L 3/20 20130101; Y02E 10/47 20130101; F24S 10/75
20180501; F24S 80/30 20180501 |
Class at
Publication: |
126/569 |
International
Class: |
F24J 2/00 20060101
F24J002/00 |
Claims
1. A solar collector comprising: a frame (1), preferably made of
extruded or rollformed metal, an absorber plate (3a), absorber
tubing (3b) secured to the rear side of the absorber plate, an
insulating layer (2) beneath the absorber plate, a cover pane (4)
spaced above the absorber, four or more mounting brackets
(11a,11b,11c,11d) for connecting the absorber (3) with the frame
(4), said mounting brackets engage the absorber tubing (3b),
whereby a first mounting bracket (11a) engages the absorber tubing
(3b) in a manner that does not allow any displacement between the
first bracket and said absorber tubing, a second mounting bracket
(11b) engages the absorber tubing (3b) in a manner that allows
displacement between the second bracket and said absorber tubing
only in a first direction in the plane of the absorber plate to
allow for thermal expansion and contraction of the absorber plate
(3a) in said first direction, a third mounting bracket (11c)
engages the absorber tubing (3b) in a manner that allows
displacement between the third bracket and said absorber tubing
only in a second direction in the plane of the absorber plate (3a)
that is substantially transverse to the first direction to allow
for thermal expansion and contraction of the absorber plate in said
second direction, and a fourth mounting bracket (11d) engages the
absorber tubing (3b) in a manner that allows displacement between
the fourth bracket and said absorber tubing in both the first and
second direction to allow for thermal expansion and contraction of
the absorber plate (3a) in said first and second direction.
2. A solar collector according to claim 1, wherein the mounting
brackets (11a,11b,11c,11d) are rectangularly spaced apart.
3. A solar collector according to claim 1, wherein the first
mounting bracket (11a) and the fourth mounting bracket (11d) are
disposed diagonally opposite to one another.
4. A solar collector according to claim 3, wherein the second
mounting bracket (11b) and the third mounting bracket (11c) are
disposed diagonally opposite to one another.
5. A solar collector according to claim 1, wherein the absorber
tubing (3b) includes tube sections that extend in the first
direction and tube sections that extend in the second
direction.
6. A solar collector according to claim 5, wherein said first
mounting bracket (11a) engages both a tube section that extends in
the first direction and a tube section that extends in the second
direction.
7. A solar collector according to claim 1, wherein said second
mounting bracket (11b) slidably engages a tube section that extends
in the first direction to allow for displacement between said tube
section and the second mounting bracket in the first direction.
8. A solar collector according to claim 1, wherein said third
mounting bracket (11c) slidably engages a tube section that extends
in the second direction and loosely engages a tube section that
extends in the first direction to allow for displacement between
said tube sections and the third bracket in the second
direction.
9. A solar collector according to claim 1, wherein said fourth
mounting bracket (11d) loosely- and slidably engages a tube section
that extends in the first direction or in the second direction to
allow for displacement between said tube section and the fourth
bracket in the first and second direction.
10. A solar collector according to claim 1, wherein said four or
more mounting brackets (11a,11b,11c,11d) are substantially
identical to one another.
11. A solar collector according claim 1, comprising a mounting
bracket (11a,11b,11c,11d), for engaging one or more tube sections
of said solar collector, said mounting bracket comprising two tube
engaging members (12,13) that can be fixed to engage a tube section
in at least two positions, a first position in which the tube
section is slidably engaged and a second position in which the tube
section is loosely engaged to allow displacement between the tube
section and the mounting bracket in a direction transverse to the
tube section axis.
12. A solar collector according to claim 11, wherein at least one
of said tube engaging members (12,13) is forked so as to embrace a
second tube section that extends transversely from the first tube
section.
13. A solar collector according to claim 11, further comprising a
base plate (15) for attaching the mounting bracket to the frame of
the solar collector, wherein said base plate (15) is provided with
three or more frame facing protrusions (19) to minimize the contact
area between the frame and the base plate (15).
14. A solar collector according to claim 13, wherein through going
bores in the base plate (15) coincide with the protrusions.
15. A solar collector according to claim 13 or 44, wherein the base
plate (15) and a first of the tube engaging members (12) are
integrally connected to one another by a connecting part (16) that
is at an angle with the base plate and the second tube engaging
member (13) being securable relative to the first tube engaging
member (13).
16. A solar collector according to claim 15, wherein the connecting
part (16) comprises a substantially flat plate section, at least a
part of the oppositely disposed free edges (17) of the flat plate
section being bent over to reinforce the mounting bracket.
17. A solar collector according to claim 16, wherein said free edge
(17) is bent over to obtain a substantially U-shaped cross-section
in which a flat plate part (14) of the second tube engaging member
is slidably received.
18. A solar collector according to claim 17, wherein the flat plate
section (14) that is integral with the first tube engaging member
is provided with one through going bore (18) and the flat plate
part of the second tube engaging member is provided with two
through going bores (18) that overlap with the through going bore
of the flat plate section in two distinct positions, whereby the
tube engaging members (12,13) slidably engage the tube section in
one of the two distinct positions and the tube engaging members
(12,13) loosely engage the tube section in the other of the two
distinct positions.
19. A solar collector according to claim 18, wherein a pop rivet,
bolt or similar fastener is received in the through going bores
(18) to fasten the second tube engaging member (13) in either of
the two distinct positions.
20. A solar collector according to claim 11, wherein said tube
engaging members (12,13) are at least partially curved with a
radius equal to or slightly larger than the tube section to be
engaged.
21. A solar collector according to claim 11, wherein at least a
part of the mounting bracket is made of a material with a
relatively low thermal conductivity, such as stainless steel, to
reduce heat loss via the mounting bracket to the frame.
Description
[0001] The present invention relates to solar collectors and
mounting brackets, in particular solar collectors that include a
rectangular frame, preferably made of extruded or rollformed metal,
containing an absorber plate, an insulating layer beneath the
absorber plate, and a cover pane spaced above the absorber.
Absorber tubing is attached to the rear side of the absorber plate.
The collectors can be integrated or roof mounted on a pitched roof,
or may be installed on a flat roof by means of a mounting
frame.
BACKGROUND ART
[0002] WO 2004/111550 discloses such a type of solar collector. The
absorber is simply inserted in the frame or another housing. The
absorber is held in place by the connection of the absorber tubes
to the frame, but it is also known to hold the absorber in place by
imbedding the absorber in the insulation material.
[0003] Neither method for securing the absorber is ideal. A stiff
connection between the absorber tubes and the frame cannot provide
for the required flexibility, which is needed to deal with the
large temperature variations and the consequent expansions and
contractions in order to avoid tensions and damages.
[0004] Absorbers that are simply placed on the insulation layer,
e.g. stone wool, and have flexible connections between the absorber
tubes and the frame, are known to have problems with the absorber
plate getting displaced during transport or during mounting of the
solar collector on a roof or the like.
[0005] EP 1 243 874 discloses a type of solar collector in which
the absorber is secured to the frame by resilient fasteners. The
resilient fasteners reduce the risk of displacement during
transport or mounting, but do not quite eliminate the problem.
Further, this solution requires that several mounting tubes are
added to the absorber construction to provide an engagement point
for the resilient fasteners.
DISCLOSURE OF THE INVENTION
[0006] On this background, it is an object of the present invention
to provide a solar collector in which the absorber is secured in a
reliable and flexible manner. This object is achieved in accordance
with claim 1 by providing solar collector comprising a frame,
preferably made of extruded or rollformed metal, an absorber plate,
absorber tubing secured to the rear side of the absorber plate, an
insulating layer beneath the absorber plate, a cover pane spaced
above the absorber, four or more mounting brackets for connecting
the absorber with the frame, said mounting brackets engage the
absorber tubing, whereby a first mounting bracket engages the
absorber tubing in a manner that does not allow any substantial
displacement between the first bracket and said absorber tubing, a
second mounting bracket engages the absorber tubing in a manner
that allows displacement between the second bracket and said
absorber tubing only in a first direction in the plane of the
absorber plate to allow for thermal expansion and contraction of
the absorber plate in said first direction, a third mounting
bracket engages the absorber tubing in a manner that allows
displacement between the third bracket and said absorber tubing
only in a second direction in the plane of the absorber plate that
is substantially transverse to the first direction to allow for
thermal expansion and contraction of the absorber plate in said
second direction, and a fourth mounting bracket engages the
absorber tubing in a manner that allows displacement between the
fourth bracket and said absorber tubing in both the first and
second direction to allow for thermal expansion and contraction of
the absorber plate in said first and second direction.
[0007] The first mounting bracket fixes the position of the
absorber to the frame, and the risk of the absorber plate getting
displaced during transport or mounting of the solar collector is
substantially eliminated. The other mounting brackets allow a
substantially unhindered thermal expansion of the absorber plate,
and this there amount of tension an stress that could otherwise be
caused during the large day/night summer/winter and stagnation
temperatures fluctuations to which a solar collectors are
exposed.
[0008] The mounting brackets may be rectangularly spaced apart, and
the absorber tubing preferably includes two parallel tubes with a
preferably larger diameter that are interconnected by a plurality
of preferably lesser diameter tubes extending between the large
diameter tubes in a direction substantially transverse to the large
diameter tubes. Preferably, the larger diameter tubes extend in the
first direction, whereas the lesser diameter tubes extend in the
second direction.
[0009] The first mounting bracket and the fourth mounting bracket
are preferably disposed diagonally opposite to one another. The
second mounting bracket and the third mounting bracket are
preferably disposed diagonally opposite to one another.
[0010] The first mounting bracket may engage both a tube section
that extends in the first direction and a tube section that extends
in the second direction, preferably there where the two tubes are
connected to one another.
[0011] The second mounting bracket may slidably engage a tube
section that extends in the first direction to allow for
displacement between said tube section and the second mounting
bracket in the first direction.
[0012] The third mounting bracket may slidably engage a tube
section that extends in the second direction and loosely engages a
tube section that extends in the first direction to allow for
displacement between said tube sections and the third bracket in
the second direction.
[0013] The fourth mounting bracket may loosely- and slidably engage
a tube section that extends in the first direction or in the second
direction to allow for displacement between said tube section and
the fourth bracket in the first and second direction.
[0014] Preferably, the four or more mounting brackets are
substantially identical to one another.
[0015] It is yet another object of the present invention to provide
a mounting bracket for use in a solar collector that assets in
overcoming the problems describer above.
[0016] This object is achieved in accordance with claim 11 by
providing mounting bracket for use in a solar collector for
engaging one or more tube sections, the mounting bracket comprising
two tube engaging members that can be fixed to engage a tube
section in at least two positions, a first position in which the
tube section is slidably engaged and a second position in which the
tube section is loosely engaged to allow displacement between the
tube section and the mounting bracket in a direction transverse to
the tube section axis.
[0017] At least one of said tube engaging members can be forked so
as to embrace a second tube section that extends transversely from
the first tube section. This allows the bracket to engage the
tubing at a connection point between two tube sections.
[0018] The mounting bracket may further include a base plate for
attaching the mounting bracket to the frame of the solar collector,
wherein said base plate is provided with three or more frame facing
protrusions to minimize the contact area between the frame and the
base plate. By reducing the contact area the heat loss at the
connection between the mounting bracket and the frame is minimized.
Through going bores in the base plate may coincide with the
protrusions, so that fasteners such a pop-rivets or bolts and nuts
can be applied there though and through corresponding bores in the
frame.
[0019] The base plate and a first of the tube engaging members are
preferably integrally connected to one another by a connecting part
that is at an angle with the base plate and the second tube
engaging member being securable relative to the first tube engaging
member. The connecting part may comprise a substantially flat plate
section, and at least a part of the oppositely disposed free edges
of the flat plate section can be bent over to reinforce the
mounting bracket. The free edge may be bent over to obtain a
substantially U-shaped cross-section in which a flat plate part of
the second tube engaging member is slidably received.
[0020] The flat plate section that is integral with the first tube
engaging member can be provided with one through going bore and the
flat plate part of the second tube engaging member can be provided
with two through going bores that overlap with the through going
bore of the flat plate section in two distinct positions, whereby
the tube engaging members slidably engage the tube section in one
of the two distinct positions and the tube engaging members loosely
engage the tube section in the other of the two distinct positions.
A pop rivet, bolt or similar fastener can be received in the
through going bores to fasten the second tube engaging member in
either of the two distinct positions.
[0021] The tube engaging members are preferably at least partially
curved with a radius equal to or slightly larger than the tube
section to be engaged.
[0022] At least a part of the mounting bracket can be made of a
material with a relatively low thermal conductivity, such as
stainless steel, to reduce heat loss via the mounting bracket to
the frame.
[0023] Further objects, features, advantages and properties of the
solar collector and mounting bracket according to the invention
will become apparent from the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In the following detailed portion of the present
description, the invention will be explained in more detail with
reference to the exemplary embodiments shown in the drawings, in
which:
[0025] FIG. 1 is a cutaway perspective view of a solar collector
according to the invention,
[0026] FIGS. 2a to 2c are partial cross-sectional views of the
solar collector of FIG. 1 at different temperatures,
[0027] FIG. 3 is a cross sectional view through the collector in
the plane of the absorber plate, illustrating mounting brackets
holding the absorber tubing,
[0028] FIGS. 4a and 4b are cross sectional views transverse to the
plane of the absorber to illustrate a detail of the engagement
between the mounting bracket and the absorber tubing, and
[0029] FIGS. 5a and 5b are perspective views showing the mounting
bracket in detail.
DETAILED DESCRIPTION
[0030] A preferred embodiment of the invention will be described
specifically with reference to a flat plate collector assembly
although it is understood that other absorber types may be employed
with a minimum change in construction.
[0031] FIG. 1 shows by way of illustrative example a flat plate
solar energy collector. Seen in cutaway perspective view of FIG. 1
the solar collector has a frame 1, an insulation layer 2, an
absorber plate 3 and a cover pane 4. The frame, the insulation
layer and the cover pane form a case with an enclosure. The
enclosure is used to provide support for the absorber, and to
protect the collector from heat loss due to wind, plus the
important function of keeping moisture from rain, snow and dew out
of the collector.
[0032] The insulation layer 2 is made of a rigid foam urethane
(PUR) or polyisocyanurate (PIR). These materials have an excellent
insulation value per unit of thickness and are easy to handle
because they are very light. They have also a higher compression
resistance than e.g. mineral wool based insulation materials.
[0033] The upper surface of the insulation layer 2 is covered with
a reflective silver foil and provided with a recess sized to be
able to receive the absorber 3. The absorber 3 is received in the
in the recess and except for its upper side surrounded by the
insulation layer 2.
[0034] As shown in FIG. 2a the absorber comprises an absorber plate
3a and an absorber tubing 3b that channels the medium, typically
water, used to transport the collected thermal energy. The absorber
plate 3a and the copper tubing 3b may suitably consist of steel,
copper or aluminum sheet or tubing, respectively.
[0035] The absorber plate 3a is provided with a semi-selective or a
selective coating to improve the heat absorbing capacity of the
absorber plate 3a.
[0036] The solar collector may also be provided with a backsheet 5
to protect the insulation layer 2 from weather influences and to
increase the rigidity of the construction. The backsheet is
suitably formed by a plastic sheet or film material weaker than the
frame material, e.g. polypropylene sheet or aluminum foil. A
backsheet can be altogether avoided if the bottom side of the
insulation layer is coated.
[0037] The frame 1 comprises four side panels that are part of one
rollformed sheet material profile. The sheet material is suitably
made of sheet metal, preferably pre-painted aluminum.
[0038] The side panels 1 are substantially shaped as a U-profile
with an upper inwardly directed latch 1a and a lower inwardly
directed latch 1b. The upper latch 1a is provided with an
upstanding rim 1c.
[0039] The details of the frame construction and the type of
insulation material are however not crucial for the present
invention, and the frame could alternatively be made from extruded
metal (aluminum) or from wood and a back sheet. A layer of mineral
wool can be sued instead of rigid foam as insulation material.
[0040] The upstanding rim 1c acts as a spacer that supports the
cover pane 4 and maintains a distance between the upper surface of
latch 1a and the bottom surface of the cover pane 4 during fitting
of the cover pane. A continuous EPDM neoprene gasket 7 is placed on
the upstanding rims 1c. The gasket 7 is in sealing abutment with a
peripheral zone of the bottom surface of the cover pane 4 to form a
moisture barrier protecting the enclosure and to insulate the cover
pane 4 thermally from the side panels 1.
[0041] The gasket is provided on its outwardly facing side with a
flexible dam 7a. The flexible dam 7a is arranged to define a hollow
space between the rim and the dam itself. The hollow space allows
the flexible dam to move unhindered. The gasket is provided on its
inwardly facing side with a flap 7b extending over the insulation
layer and under the absorber 3. The flap protects the silver foil
and the insulation layer from the sides of the absorber plate
3a.
[0042] When the gasket has been placed on the rim 1c, the cover
pane 4 is placed on top of the gasket 7 and the space between the
upper side of the latch 1a and the bottom surface of the cover pane
4 is filled with a flexible adhesive sealant such as a silicone
based sealant in liquid form. The flexible dam 7a serves as a
barrier preventing the liquid flexible adhesive sealant from
entering the cavity when it is applied.
[0043] When the sealant has cured it forms a flexible layer that
securely attaches the cover pane 4 to the side panels.
[0044] The layer of flexible adhesive sealant also forms a second
moisture barrier protecting the enclosure. The enclosure is thus
protected from moisture by a two-stage barrier, thus, reducing the
likeliness of leakage significantly.
[0045] The layer of flexible adhesive sealant attaches the cover
pane 4 to the side panels so that the cover pane 4 becomes an
integral bearing part of the construction that contributes to the
overall stability and stiffness of the solar collector. There is
therefore no need for capstrips and thus there is no risk of water
or snow to remain caught at the transition between the cover pane
and the capstrip.
[0046] FIG. 2a illustrates the cross-section of the solar collector
at room temperature. Since this is the temperature at which the
cover pane was fitted to the frame there are no discrepancies in
length between the aluminum frame and the tempered glass cover
pane.
[0047] FIG. 2b illustrates the cross-section of the solar collector
at a high temperature such as may e.g. occur during stagnation,
i.e. when the heat transporting medium is not flowing so that the
heat is not transported away. The cover pane has expanded more than
the frame with the temperature raise. The difference in length is
compensated for by an outwardly directed shear deformation of the
layer of flexible adhesive sealant 8.
[0048] FIG. 2c illustrates the cross-section of the solar collector
at a low temperature such as may e.g. occur in a cold winter night.
The cover pane has contracted more than the frame with the
temperature fall. The difference in length is compensated for by an
inwardly directed shear deformation of the layer of flexible
adhesive sealant 8.
[0049] Flexible adhesive sealants such as silicon based sealant can
well endure such deformation and still maintain good adhesion to
the cover pane and the frame both at low and high temperatures.
Because of the low elasticity modus of the flexible adhesive
sealant the shear forces acting on the cover pane and the frame are
negligible.
[0050] As shown in FIG. 3, the absorber tubing includes two
horizontally (horizontal as in FIG. 3) directed tubes 3c with a
larger diameter that are interconnected by a plurality of
vertically (vertical as in FIG. 3) directed lesser diameter tubes
3b extending between the large diameter tubes in a direction
substantially transverse to the large diameter tubes 3c.
[0051] Although not shown, all tubing 3b and 3c may be of equal
diameter.
[0052] The lower (low as in FIG. 3) of the two larger diameter
tubes 3c is connected via a section of flexible tubing 9a to a
bracket 10a that is secured to the frame 1 and includes a conduit
(not shown) extending to the outside of the frame 1 for connection
to external tubing or a juxtaposed collector (not shown).
[0053] The higher (high as in FIG. 3) of the two larger tubes 3c is
connected via a section of flexible tubing 9b to a bracket lob that
is secured the frame 1 and includes a conduit (not shown) extending
to the outside of the frame 1 for connection to external tubing or
a juxtaposed collector.
[0054] The flexible tubing sections 9a and 9b ensure that the
absorber plate 3a and absorber tubing 3c can thermally expand and
contract without any tension building up at the connection between
the absorber tubing 3b,3c and the frame 1.
[0055] Four mounting brackets 11a,11b,11c,11d support the absorber
3. These four mounting brackets are identical in construction, but
can engage the absorber tubing in four different ways. The mounting
brackets 11a,11b,11c,11d are rectangularly spaced apart and extend
from the frame 1 to engage the absorber tubing 3b,3c. The mounting
brackets 11a-11d are configured to be able to engage the larger
diameter tubing 3c either slidably, thereby allowing displacement
between the larger diameter tubing 3c and the mounting bracket in
the direction of the tube axis, or loosely, thereby allowing both a
limited displacement between the tube and the mounting bracket
transversely to the tube axis and unlimited displacement in the
direction of the tube axis. The brackets are configured to be able
to engage simultaneously a larger diameter tube either slidably or
loosely and a lesser diameter tube slidably at a point where the
two tube types are connected to one another at substantially right
angles. The engagement structure of the mounting bracket will be
described in more detail further below with.
[0056] The first mounting bracket 11a engages the absorber tubing
in the left lower corner (left and lower as in FIG. 3) at a point
where the leftmost lesser diameter tube 3b connects to the lower
larger diameter tube 3c. The first mounting bracket engages both
the large diameter tube 3c and the lesser diameter tube 3b, thereby
ensuring that the absorber 3 cannot be displaced relative to the
frame 1.
[0057] The second mounting bracket 11b engages the absorber tubing
in the right lower corner (right and lower as in FIG. 3), and only
engages the lower larger diameter tube 3c in a slidable manner so
to allow for movement of the lower tube 3c relative to the second
bracket 11b in the direction of arrow X. Thus, thermal expansion of
the absorber 3 in the direction of arrow X can take place
substantially unhindered by the connection between the frame 1 and
the absorber 3 formed by the second mounting bracket 11b.
[0058] The third mounting bracket 11c engages the absorber tubing
in the upper left corner (upper and left as in FIG. 3), and both
engages the upper larger diameter tube 3c and the left first lesser
diameter tube 3b. The third bracket 11c engages the leftmost lesser
diameter tube 3b in a slidable manner (slidable in the direction of
the tube axis, i.e. in the direction of arrow Y). The third bracket
loosely engages the upper tube 3c to so as to allow for a limited
amount of movement of the upper tube 3c relative to the third
bracket in the direction of arrow Y. Thus, thermal expansion of the
absorber 3 in the direction of arrow Y can take place substantially
unhindered by the connection between the frame 1 and the absorber 3
formed by the third mounting bracket 11c.
[0059] The fourth mounting bracket 11d engages the absorber tubing
in the upper right corner (upper and right as in FIG. 3). Only the
upper larger diameter tube 3c is engaged loosely by the fourth
third bracket 11d, thereby allowing displacement of the absorber in
the direction of both the X and Y arrow. Thus, thermal expansion of
the left part of the absorber 3 in the direction of arrow Y and in
the direction of arrow Y can take place substantially unhindered by
the connection between the frame 1 and the absorber 3 formed by the
fourth mounting bracket 11d.
[0060] FIG. 4a shows a cross-sectional view through the first
mounting bracket 11a in a plane at right angles with the tube axis
of the large diameter tubes 3c. The mounting bracket 11a is secured
with a base plate 15 to the frame 1. The base plate 15 is at a
right angle with a connecting part 16 that further extends into a
curved first tube engaging member 12. The mounting bracket 11a
includes further a second curved tube engaging member 13. The
second tube engaging member 13 includes a flat plate part 14 that
is secured to the connecting part 16. The second tube engaging
member can be secured in a two positions to obtain the above
described slidable or loose engagement. In FIG. 4a the second tube
engagement member is in the position that gives a slidable
engagement. The first tube engagement member 12 is forked and the
lesser diameter tubing 3a is embraced by the fingers of the
fork.
[0061] FIG. 4b shows a cross-sectional view through the third
mounting bracket 11c in a plane at right angles with the tube axis
of the large diameter tubes 3c. The third mounting bracket 11c is
identical to the first mounting bracket 11a, except that the second
tube engaging member 13 is secured in the position for engaging the
larger diameter tube 3c in a loose manner.
[0062] FIG. 5a shows the mounting bracket 11a-11d in a perspective
view with the second tube engaging member in the slidable
engagement position. FIG. 5b shows the mounting bracket 11a-11d in
a perspective view with the second tube engaging member in the
loose engagement position. These Figs. show the recess 22 in the
forked first tube engaging member in which a lesser diameter tube
3b can be received. The base plate 15 is provided with three frame
facing protrusions 19 to minimize the contact area between the
frame 1 and the base plate 15. By reducing the contact area the
heat loss at the connection between the mounting bracket 11a-11d
and the frame 11 is minimized. Through going bores in the base
plate 15 coincide with the protrusions, and fasteners such a
pop-rivets or bolts and nuts are applied there though and through
corresponding bores in the frame 1 to fasten the mounting bracket
11a-11d to the frame 1.
[0063] The connecting part 16 includes substantially flat plate
section 21, with oppositely disposed bend over free edges 17 that
serve to reinforce the mounting bracket 11a-11d. The free edges 17
create a U-shaped cross-section in which the flat plate part 14 of
the second tube engaging member 13 is slidably received.
[0064] The flat plate section 21 is provided with one through going
bore (cannot be seen in the Figs.) and the flat plate part 14 of
the second tube engaging member 13 is provided with two through
going bores 18 that overlap with the through going bore of the flat
plate section 21 in two distinct positions. The tube engaging
members 12,13 slidably engage the larger diameter tube 3c in one of
the two distinct positions and the tube engaging members loosely
12, 13 engage the larger diameter tube 3c in the other of the two
distinct positions. A pop rivet, bolt or similar fastener is fitted
in the through going bores 18 to fasten the second tube engaging
member 13 in either of the two distinct positions.
[0065] The tube engaging members 12,13 are at least partially
curved with a radius equal to or slightly larger than the larger
diameter tubes 3c. The mounting brackets 11a-11d, or at least a
part thereof, are made of stainless steel, or other suitable
material with a relatively low thermal conductivity to reduce heat
loss via the mounting bracket to the frame 1.
[0066] The same mounting bracket 11a-d is used to engage the
absorber tubing in different ways: [0067] The mounting bracket can
fork or slide. [0068] In addition it can be secured (pop riveted)
in a closed or open situation for sliding and loose engagement with
the absorber tubing.
[0069] Very large absorbers can be supported by 6, 8 or mere
brackets, that engage the absorber tubing with an individually
determined amount of freedom in displacement between the mounting
bracket and the absorber tubing in accordance with the particular
requirement at the point of engagement.
[0070] Although the present invention has been described in detail
for purpose of illustration, it is understood that such detail is
solely for that purpose, and variations can be made therein by
those skilled in the art without departing from the scope of the
invention.
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