AU2011355592B2

AU2011355592B2 - A sealing arrangement for a solar collector enclosure

Info

Publication number: AU2011355592B2
Application number: AU2011355592A
Authority: AU
Inventors: Glen BOLITHO; Gregory Chapman; Joseph REARDON
Original assignee: Rheem Australia Pty Ltd
Current assignee: Rheem Australia Pty Ltd
Priority date: 2011-01-12
Filing date: 2011-12-22
Publication date: 2015-10-29
Anticipated expiration: 2031-12-22
Also published as: WO2012094699A1; NZ613066A; AU2011355592A1

Abstract

A sealant channel arrangement for forming a seal between first and second bodies having complementary interface surfaces includes an open channel 6.098 formed in the interface surface of the first body, and a sealant injection aperture 6.096 in the form of a through hole accessible from the opposite side from the first interface surface. When the two bodies are assembled, the interface surface 6.048 of the second body forms a cover over the channel. A purge point 6.100 is arranged to be visible when the two components are assembled.

Description

1 A SEALING ARRANGEMENT FOR A SOLAR COLLECTOR ENCLOSURE Field of the invention [001] This invention relates to a sealing arrangement for forming a seal on components of an enclosure. [002] The invention will be described in the context of a weather seal for a solar collector enclosure. Background of the invention [003] Solar collector panels generally include a heat transfer fluid circuit having risers and headers enclosed in a box with a transparent lid, usually of glass or other transparent material, to permit the solar energy to impinge on the risers. The enclosure can be made of a number of components, such as side panels and corner mouldings. This invention can be used in conjunction with solar collector enclosures such as that described in our co-pending applications of even date, entitled A SOLAR COLLECTOR VENTILATION ARRANGEMENT of Australian patent application number 2011355593, and A SOLAR COLLECTOR DRAINAGE ARRANGEMENT of PCT patent publication number WO 2012/094698 Al. [004] It is desirable to provide a means for providing a substantially weather tight seal between the structural components of the enclosure. Summary of the invention [005] The present invention provides a sealing arrangement for sealing first and second members each having a corresponding first or second overlapping interface portion, a sealant channel being formed on the interface surface of the second interface portion, and a sealant injection aperture formed in the first or second member and providing access to the sealant channel for the injection of sealant into the sealant channel, the sealing arrangement further including an overflow recess adapted to receive sealant from at least one purge point located at an end of the sealant channel. [006] The overlapping interface portions can be planar. [007] The first and second members can be held together by engagement means which hold the first and second members together. [008] The engagement means can include a slide arrangement.

2 [009] The slide arrangement can include at least one channel in one member, and at least one conforming slide profile on the other member adapted to slide within the corresponding channel. [010] At least part of the purge point can be visible when the first and second members are assembled. [011] The attachment means can be a snap-fit arrangement. [012] The present invention also provides a sealant injection channel adapted to receive a sealant to form a seal between a first body and a second body having complementary first and interface areas, the sealant channel being a first open channel formed in the first interface surface, and having an injection aperture in the from of a through hole communicating with the opposite side of the first interface surface, wherein the sealing arrangement further includes an overflow recess adapted to receive sealant from at least one purge point located at an end of the sealant channel. [013] The sealant can be flowable. [014] The sealant can be thixotropic. [015] The second interface surface can form a cover over the channel. [016] At least part of the purge point can be visible when the first and second bodies are assembled. [017] The sealant injection channel can include a second sealant channel transverse to, and intersecting the first sealant channel. [018] The second sealant channel can be a keyway. [019] The second sealant channel can be shallower than the first sealant channel. [020] The sealing arrangement can include one or more air purge pathways in fluid communication with the sealant channel. [021] The air purge pathways can be sufficiently narrow to prevent substantial ingress of sealant into the air purge pathways, providing a self-limiting flash. [022] The sealant can also be an adhesive.

3 [023] The viscosity of the sealant and the width of the purge pathways can limit penetration of the sealant into the air purge pathways. Factors influencing viscosity include the specific batch, temperature, and humidity. [024] The present invention further provides a corner moulding for an enclosure, including such a sealant arrangement. [025] The present invention also provides an enclosure including such a corner moulding, and a wall formed of an extrusion, the corner moulding being the first body, and the wall extrusion being the second body. Brief description of the drawings [026] An embodiment or embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [027] Figure 1 is a schematic illustration of a solar collector. [028] Figure 2 is a partial section view of a solar collector having pipe risers. [029] Figure 3 is a partial section view of a solar collector having an alternative collector panel. [030] Figure 4 illustrates a novel extrusion adapted for forming the walls of a solar collector enclosure according to an embodiment of the invention. [031] Figure 5 illustrates a corner assembly according to an embodiment of the invention adapted for use with the extrusion of Figure 4. [032] Figure 6 is a partial illustration of the seal duct arrangement according to an embodiment of the invention. . [033] Figure 7 is an enlarged partial view of a section of a corner moulding and wall extrusion according to an embodiment of the invention. [034] Figure 8 is a cut-away illustration of the corner of a solar collector enclosure according to an embodiment of the invention. [035] Figure 9 shows detail of the edge of a base plate sealed in position. [036] The numbering convention used in the drawings is that the digits to the left of the full stop indicate the drawing number, and the digits to the right of the full stop are the element reference numbers. Where possible, the same element reference number is used in different drawings to indicate corresponding elements.

4 [037] It is understood that, unless indicated otherwise, the drawings are intended to be illustrative rather than exact representations, and are not necessarily drawn to scale. The orientation of the drawings is chosen to illustrate the features of the objects shown, and does not necessarily represent the orientation of the objects in use. Detailed description of the embodiment or embodiments [038] Illustrated in Figure 1 is a simplified illustration of a solar collector. 1.002 having an enclosure box 1.004. The box includes side walls 1.006 with a peripheral seat 1.010 for a glass cover (not shown). The glass is sealed to the box around the peripheral seat. [039] In Figure 1, the heat transfer path includes an upper and lower header 1.018, 1.016 and a plurality of riser pipes 1.014 providing a fluid path between the hollow headers. An inlet for the heat transfer fluid is provided at 1.022, and an outlet for the heated heat transfer fluid is provided at 1.020. Similar arrangements can be used for both direct and indirect heat transfer fluid systems. [040] Solar collectors are exposed to ambient weather conditions, and it is desirable to inhibit the ingress of water into the enclosure. In an embodiment of the invention, the enclosure is formed using extrusions for the walls and moulded corner pieces to join the wall extrusions. The wall extrusions and corner mouldings need to be provided with a weatherproof seal arrangement [041] Figure 2 illustrates a section of a first embodiment of a solar collector. The wall extrusion 2.024 (described in detail in Figure 4) includes an external overhang 2.040 which can serve for use in lifting the collector by installers when installing the collector on a roof or other location, and an external channel 2.025 which can be used for fixing the collector assembly to its mount or mounting structure. [042] The overhang also provides impact protection for the edge of the toughened glass cover and can shield external portions of grommets and rubber fittings to reduce weathering thereof. [043] The glass cover 2.034 is seated on a peripheral seat provided by the wall extrusion 2.024 and channel and cooperating corner assemblies such as those illustrated in Figure 5, and is sealed thereto. [044] The risers 2.014 in this embodiment are located under and in thermal contact with an absorber plate 2.032. Thus the solar energy can pass through the 5 glass 2.034 and impinge on the absorber plate 2.032 from whence the heat is thermally conducted to the risers 2.014 for delivery to the outlet header. [045] A base plate or panel 2.026 closes off the lower side of the enclosure. The extrusion 2.024 includes a channel 4.056 for receiving the edges of the base plate or panel 2.026, and the corner assemblies (illustrated in Figure 5) also include seats 5.087 for the corners of the base plate or panel 2.026. [046] Insulation 2.028 is provided between the collector risers 2.014 and the base plate or panel 2.026. [047] In Figure 3 is an alternative assembly where multiple risers are formed in a unitary manner in a plate 3.038, which is assembled in much the same way as in the preceding description except that the absorber plate 2.032 is not required as the riser plate 2.038 has an upper surface which serves the same function. [048] Figure 4 illustrates the wall extrusion profile. The wall 4.048 has upper formations including: external overhang 4.040 forming a corner cap attachment (channel A); internal glass seat seal formations 4.042; internal corner cap attachment channel 4.044 (channel B); the top of channel 4.044 forms a glass seat rim 4.045; internal corner wall attachment channel 4.046 (channel C); internal corner wall attachment channel 4.052 (channel D); base plate receiving channel 4.056; external fixing channel 4.050. [049] Figure 5 illustrates a corner assembly according to an embodiment of the invention. The corner assembly includes a cap 5.070 and a wall segment 5.082. The cap and wall segment are adapted to conform to the shape of the wall extrusions and its recesses. [050] The cap 5.070 includes an overhang 5.072 which forms a continuation of the extrusion overhang 4.040. In addition the cap overhang 5.072 includes a projection 5.074 which is adapted to be a close fit within the underside of the extrusion overhang 4.040. The cap 5.070 includes a second projection 5.076 which is likewise adapted to fit under channel 4.044 of the extrusion.

6 [051] The cap also includes a glass seat 5.080 and seal formations 5.078. The cap wall 5.079 extends downward below the glass seat and transversely thereto. [052] The corner wall segment includes a pair of intersecting walls 5.084, 5.086 with projecting spigots 5.088, 5.090, 5.092, 5.094 adapted for insertions in the channels C & D of the wall extrusion. The lower spigots 5.092, 5.094 include drain channel slots. [053] A sealant injection point 5.096 communicates with a sealant channel 5.098 so that sealant can be injected into the sealant channel when the corner assembly is joined to the wall extrusions. A purge point 5.100 is provided at the top of the sealant channel and the end of the purge point is located so that the end of the purge point is visible beyond the edge of the extrusion, providing a view point to observe the purge point to determine when the sealant channel is full. A similar sealing injection point, sealant channel and purge point are provided on corner wall 5.086. [054] The base plate channel 5.087 accommodates the corner of the base plate inserted in the base plate channel 4.056 of the wall extrusion. [055] The cap 5.070 and corner wall segment 5.082 can include a snap fit arrangement to attach the cap to the corner wall segment. [056] The corner moulding of Figure 5 is adapted for attachment with the wall extrusion of Figure 4. To that end, the corner moulding includes upper engagement projection 5.088 adapted for sliding insertion in channel 4.046 of the wall extrusion of Figure 4, and lower engagement projection 5.090 adapted for sliding insertion in channel 4.052 of the wall extrusion of Figure 4. When the corner moulding and wall extrusion are assembled, the sealant channel is within the interface between the wall segment 4.048 of the wall extrusion, and the wall segment 5.084 of the corner moulding, forming a substantially closed channel, while the sealant injection point 5.096 is accessible from the inside of the enclosure so that silicone or other sealant can be injected into the sealant channel via the sealant injection point. [057] Figure 6 is a partial view of a corner moulding showing the sealant injection point 6.096 and sealant channel 6.098. The sealant injection point 6.096 is a through hole in the wall 6.084. The sealant channel 6.098 runs the full height of the wall terminating at the top in a cutaway 6.102 and an adjoining purge point 6.100. The lower end of the sealant channel terminates in a second cutaway 6.104.

7 [058] A shallower transverse channel 6.106, 6.108 transects the upright sealant channel 6.098 above the cutaway 6.104 to provide a keyway for rib 4.055 (Figure 4) to limit grabbing between the plastic corner moulding and the aluminium extrusion. When the wall extrusion and corner moulding are assembled, the transverse channel is within the wall of the channel 6.052, so a transverse sealing/bonding strip may be formed between the corner moulding and the wall extrusion, in addition to that formed by upright channel 6.098. [059] A raised bead or raised edge 6.110 forms an abutment for the end of the wall extrusion when the extrusion and moulding are assembled together. The abutment is located so that the end of the purge point 6.100 projects beyond the edge of the wall extrusion so that the purge point can be observed so as to determine when the sealant emerges at the purge point. The sealant channel and the sealant injection point are dimensioned so that the sealant will flow in both directions to arrive at the cutaways at about the same time. Preferably, to ensure a full seal, the sealant should arrive at purge point 6.100 after it has reached the lower cutaway 6.104. The extrusion wall 6.048 forms a cover over the sealant channel 6.098 when the extrusion and moulding are assembled. This substantially confines the sealant within the channel 6.098 along the length of the channel. [060] The top of the wall 6.084 and the end 6.103 of the cap (dotted outline) together with the end of the wall extrusion can be shaped to provide an overflow recess fed from the purge point 6.100. This allows for variations in the viscosity of the sealant and other variables such as the sealant pump pressure. In this embodiment, the top of the wall is chamfered at 6.101, and the cap has a cutout at 6.103. [061] Figure 7 is a close up detailed illustration of the lower wall extrusion 7.024 and corner moulding 7.084. The wall extrusion channel 7.052 receives the corner moulding projection 7.090 in a sliding fit. The dimensions of the wall extrusion and the corner moulding are such as to leave gaps 7.114 and 7.116. These gaps provide an air purge path so that, as the sealant is injected into the sealant channel, the air can escape from the sides of the sealant channel via these gaps. This ensures a good surface contact area between the two bonded substrates (extrusion and moulding) at the strongest areas of the shapes of both components and also ensures a full weather seal between the two substrates. This gap also permits optimum thermal expansion provision on the structural joint, i.e., provision for greater movement/elongation in silicone reduces strain on the silicone joint. This also assists in limiting overfill to provide a clean joint between substrates.

8 [062] The projecting key 7.055 in the wall extrusion channel 7.052 and the mating keyway 7.119 in the corner moulding perform a number of functions. First, the key and keyway control the gaps 7.114, 7.116. They also act as a guide mechanism to assist the corner block to engage squarely. The keyway arrangement also assists in preventing the corner moulding from grabbing on the cut edge of the aluminium profile. The keyway also has the benefit of 'locking in' the corner block upon full insertion. The keyway feature can be modified in an aluminium die to relax or increase the clearance. [063] The air purge gaps can be sufficiently narrow so that the viscosity of the sealant prevents significant ingress of the sealant into the air purge pathways. [064] The sealant also acts as an adhesive to bond the corner moulding and wall extrusion together. [065] Figure 8 is a cutaway partial view illustrating detail of the sealant channel. Figure 8 illustrates the corner assembly with walls 8.084, 8.086 and wall extrusions 8.024. A cut away section of the base 8.026 is shown assembled into the base retention slots 8.056. Water which enters the enclosure, for example under the glass seal in the event of a seal failure or by water condensed from air inside the collector, will run down the inner wall of the wall extrusion and accumulate in the extrusion channel such as 8.052. The engagement spigots 8.090, 8.094 engage the corresponding channels in the wall extrusions so the entrance to the drainage channels such as 8.150 are directed to the extrusion engagement channels such as 8.052 to receive water which has collected in the extrusion channels 8.052 and divert it to the exterior of the enclosure via aperture 8.152 and recess 8.154. As Figure 8 shows, the channels 8.150 communicate from the interior of the enclosure across the sealant channels 8.098 to the external aperture 8.152. The sealant runs across the bottom of the attachment projection 8.090 in the lower cutaway 8.104 of the sealant channel. The lower cutaway 8.104 opens out to permit sealant to contact the mating surface of the wall extrusion channel such as 7.052 in Figure 7. [066] Should the external aperture 8.152 become obstructed or if the flow is too great for a single outlet, the water will be retained by dam wall 8.160 and flow around the bend to the next drain channel in spigot 8.094. Because there is a similar drainage feature at each corner of the enclosure, the diversion via the dam 8.160 will provide at least two additional drainage paths, one at either end of the extrusion wall to which the flow from the first drainage channel has been diverted.

9 [067] The drainage path shown in Figure 8 includes an upright segment formed by the recess 8.154 and a transverse segment formed by the drainage channel 8.150. As the upright segment faces downward, this assists in preventing ingress of water via the drainage path. The bend in the path formed by the intersection of the upright segment and the transverse segment also assists in preventing water ingress. [068] Figure 9 shows detail of an edge of the base plate 9.026 sealed into the base plate channel 9.056. The base plate 9.026 can be assembled into the frame as follows. The frame, including four wall extrusions and four corner mouldings, can be loosely aligned with the connection spigots of the corner mouldings partially inserted into their respective channels or slots in the wall extrusions, but not yet pushed home. The base plate 9.026 can then be seated on the base plate 9.056 channel steps of 9.060 the wall extrusions and the complementary continuations of the step on the corner mouldings. A bead of sealant 9.310 of a predetermined size can be applied in the base channel 9.056 and the extensions in the corner moulding, or the sealant can be applied to the periphery of the base plate so it will enter the base plate channels on assembly. The frame can be then be pushed home by, for example first pushing the opposed long sides inward. This causes the base plate 9.026 to be pushed into the base plate channels 9.056. Because the edges of the base plate 9.026 engage the respective base plate channel entrance tapers 9.304 on both wall extrusions, the base plate 9.026 is automatically aligned laterally. As the edges of the plate 9.026 enter the channel 9.056, the sealant 9.310 is pressed into the channel by the base plate 9.026, and the sealant 9.310 also provides some viscous or resilient resistance to the edges of the base plate 9.026 and this can also assist in the alignment of the base plate 9.026, resulting in the sealant bead shown at 9.310 of Figure 9. Pushing the wall extrusions inward also causes these wall extrusions to fully engage with the corner mouldings. The other two opposed sides can then be pushed home so the base plate 9.026 enters the base plate channels 9.056 on these wall extrusions in the same way. Thus the base plate assembly process automatically aligns the base plate 9.026 and seals the base plate 9.026 in the base plate channels 9.056 of the wall extrusions and the corner mouldings as shown in Figure 9. [069] Once the base plate has been assembled, the glass cover can be sealed by assembly robot equipment as follows: 1. The finished collector tray is held against a datum and jigged square; 2. A "J" -shaped insert (Skirt-Trim profile) is clipped into channel 4.044 (B) of the 10 aluminium profile; 3. A robot lays down a consistent volume and size of sealant bead around the perimeter of the collector panel at a specific location on glazing silicone seat/bed 4.042; 4. The glass is picked up with manipulator and measure checked via sensors to ensure glass is within specification tolerance and the coordinate position is automatically adjusted to place glass centrally and firmly onto collector panel tray/silicone bead. [070] In this specification, reference to a document, disclosure, or other publication or use is not an admission that the document, disclosure, publication or use forms part of the common general knowledge of the skilled worker in the field of this invention at the priority date of this specification, unless otherwise stated. [071] In this specification, terms indicating orientation or direction, such as "up", "down", "vertical", "horizontal", "left", "right" "upright", "transverse" etc. are not intended to be absolute terms unless the context requires or indicates otherwise. These terms will normally refer to orientations shown in the drawings unless the context requires otherwise. [072] Where ever it is used, the word "comprising" is to be understood in its "open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is the sense of "consisting only of'. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear. [073] It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text. All of these different combinations constitute various alternative aspects of the invention. [074] While particular embodiments of this invention have been described, it will be evident to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments and examples are therefore to be considered in all respects as illustrative and not restrictive, and all modifications which would be obvious to those skilled in the art are therefore intended to be embraced therein.

Claims

1. A sealing arrangement for sealing first and second members each having a corresponding first or second overlapping interface portion, a sealant channel being formed on the interface surface of the second interface portion, and a sealant injection aperture formed in the first or second member and providing access to the sealant channel for the injection of sealant into the sealant channel; wherein the sealing arrangement further includes an overflow recess adapted to receive sealant from at least one purge point located at an end of the sealant channel.

2. A sealing arrangement as claimed in claim 1, wherein the overlapping interface portions are planar.

3. A sealing arrangement as claimed in claim 1 or claim 2, including engagement means which hold the first and second members together.

4. A sealing arrangement as claimed in claim 3, wherein the engagement means include a slide arrangement.

5. A sealing arrangement as claimed in claim 4, wherein the slide arrangement includes at least one channel in one member, and at least one conforming slide profile on the other member adapted to slide within the corresponding channel.

6. A sealing arrangement as claimed in any one of claims 1 to 5, wherein at least part of the purge point is visible when the first and second members are assembled.

7. A sealing arrangement including a sealant injection channel adapted to receive a sealant to form a seal between a first body and a second body having complementary first and interface areas, the sealant channel being a first open channel formed in the first interface surface, and having an injection aperture in the form of a through hole communicating with the opposite side of the first interface surface; wherein the sealing arrangement further includes an overflow recess adapted to receive sealant from at least one purge point located at an end of the sealant channel. 12

8. A sealing arrangement as claimed in claim 7, wherein the second interface surface forms a cover over the channel.

9. A sealing arrangement as claimed in claim 6 or 8, wherein at least part of the purge point is visible when the first and second bodies are assembled.

10. A sealing arrangement as claimed in any one of claims 1 to 9, including a second sealant channel transverse to, and intersecting the first sealant channel.

11. A sealing arrangement as claimed in claim 10, wherein the second sealant channel is a keyway.

12. A sealing arrangement as claimed in claim 10 or 11, wherein the second sealant channel is shallower than the first sealant channel.

13. A sealing arrangement as claimed in any one of the preceding claims, including one or more air purge pathways in fluid communication with the sealant channel.

14. A sealing arrangement as claimed in claim 13, wherein the air purge pathways are sufficiently narrow to inhibit substantial ingress of sealant into the air purge pathways.

15. A sealing arrangement as claimed in any one of the preceding claims, wherein the sealant is also an adhesive.

16. A corner moulding for an enclosure, the moulding including a sealing arrangement as claimed in any one of the preceding claims.

17. An enclosure including a corner moulding as claimed in claim 16, and a wall formed of an extrusion, the corner moulding being the first body, and the wall extrusion being the second body. 13

18. A solar collector enclosure including a sealing arrangement as claimed in any one of claims 1 to 15.