Patent Publication Number: US-9422727-B2

Title: Panel joint and seal

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of and claims priority to U.S. Ser. No. 13/275,002 filed Dec. 17, 2011, which claims priority to U.S. Ser. No. 10/793,944 filed Mar. 8, 2004, which issued as U.S. Pat. No. 8,037,657 on Oct. 18, 2011, which claims priority to Swedish Application No. 0300642 filed Mar. 11, 2003. 
    
    
     The present invention relates to sealing of a joint comprising glued edges. Prefabricated surface elements which at their edges are provided with groove and tenon are well known nowadays. As these are very easy to install, it is possible for the normal handy man to achieve this. Such elements can be constituted of massive wood, fibre board or particle board. These are often provided with a surface layer, such as lacquer or some sort of laminate. The boards are most often installed by gluing them together via their groove and tenon. It is desired to join the separate elements so closely that the joint becomes practically invisible, which increases the moisture resistance radically. The usable life of the installed elements are hereby also increased. It is essential that glue is used excessively in order to achieve a tight joint. Any gaps will make it possible for moisture to penetrate the joint with subsequent swelling of the core material closest to the joint. The glue also have to be used to an amount that it is spill out trough the joint on the decorative side of the surface elements. The superfluous glue will of course have to be wiped off before beginning to set, which is very time consuming. 
     One way of solving the problem is available on the market for some time now through different types of so-called click or snap-lock floor boards where no glue is to be used. The installation of such floor boards has become much swifter as no glue is required and the locking systems will in most cases provide adequate mechanical strength keeping the floor boards together. The problems with these type of surface elements are that relatively small spills of fluids like water may cause great damage on the installed surface elements as well as sub walls and especially subfloors as the fluid will run through the joints rather rapidly due to the capillary effect. It is, of course, possible to use glue on these snap-lock type of elements as well although the problem with the time consuming cleaning during installation would remain. 
     It has, through the present invention, been made possible to solve the above mentioned problems so that self sealing surface elements can be achieved. Accordingly the invention relates to a joint for panels, the panels comprising a core, a decorative upper surface and edges provided with joining means for positioning the panels towards one another. Predetermined portions of the edges are provided with a layer of polymer. The panels are joined to one another by use of the joining means where the polymer forms a seal in the joint preventing penetration of water into the joint wherein a highly water resistant unit of a plurality of panels is founed. 
     The panels are according to one embodiment of the invention provided with male and female edges, the male edges being intended to being joined with the female edges. According to another embodiment of the invention at least two of the edges arranged on opposite sides of the panel are provided with female edges which are joined together by means of a separate profile having two mail edges. 
     According to one preferred embodiment of the invention predetermined parts of mating surfaces of the male edges and female edges respectively are each provided with the layer of polymer. It is advantageous to coat at least the parts of the edges closest to the upper decorative surface as this will protect the core material from absorbing moisture and spills from above. 
     It is suitable to choose a polymer for the mating surfaces which migrates and merges to form a unit. There are a number of known polymers which have this property. It is advantageous to use a polymer with good storage stability and which do not dry out or form skin before the installation. 
     As an example of a polymer which may be used can be mentioned contact glue which normally is of a nitril rubber type. The disadvantage with this polymer system is that it dries out and crystallise rather quickly, and is therefore not the best of choices. It might however be used if reactivated in connection to the assembly by adding a solvent or by heating the joint. 
     Another example of a polymer which is suitable is non-curing thermoplastic sealants like a butyl rubber. One specific example of such a polymer which has shown to be useful is Bostic® Butyl 1124. It is also possible to use polymers like ethyl-vinyl-acetate (EVA) or polymer blends containing EVA. 
     It is also possible to use natural resins like for example natural bitumen and also different types of oil distillate like technical bitumen. 
     It is advantageous if the polymer is water repellent. 
    
    
     
       The invention is described further in connection to enclosed drawing showing different embodiments of the invention whereby; 
         FIG. 1  shows a first embodiment of adjacent edges of two panels to be joined according to the present invention. 
         FIG. 2  shows a second embodiment of adjacent edges of two panels to be joined according to the present invention. 
         FIG. 3  shows a third embodiment of adjacent edges of two panels to be joined according to the present invention. 
         FIG. 4 a -4 c    shows a special embodiment of adjacent edges of two panels to be joined according to the present invention. 
         FIG. 5  shows a rectangular panel of the present invention. 
     
    
    
       FIG. 1  shows, in cross-section, two adjacent edges according to a first embodiment of the invention. The panels  1  are provided with a first assembly joining member  10 ′ on a male edge  2 ′ while a female edge  2 ″ is provided with a second assembly joining member  10 ″. The female edge  2 ″ is arranged on a side opposite to the male edge  2 ′. The first assembly joining member  10 ′ is provided with a lower snapping web  26  arranged on the lower side of a tongue. The lower snapping web  26  is intended to interact with a recess  27  arranged on a lower cheek  28  arranged on the second assembly joining members  10 ″ so that two joined adjacent panels  1  are locked against each other in a horizontal direction. The lower cheek  28  forms a lower surface of a groove  30  in the female edge  2 ″. 
     The joint between a male and a female edge  2 ′ and  2 ″ respectively of two joined panels  1  further comprises contact surfaces which are constituted by the lower snapping web  26  and recess  27 , the tongue  29  and groove  30  as well as upper male and female mating surfaces  25 ′ and  25 ″ respectively. These upper male and female mating surfaces  25 ′ and  25 ″ respectively are provided with recesses in which a polymer sealer  31  is applied. This polymer is suitably a non-curing thermoplastic elastomeric sealant which will merge over the edge once assembled so that the two separate polymer sealers  31  will fuse over time to form one elastic seal. It is also possible to utilise other thermoplastic elastomers where only one of the upper mating surfaces  25 ′ or  25 ″ respectively are provided with a polymer sealer  31  comprising a plasticiser while the other upper mating surface  25 ′ or  25 ″ respectively is provided with a polymer sealer  31  lacking this plasticiser. Once the panels are joined and the polymer sealer  31  of the two mating surfaces  25 ′ and  25 ″ respectively, are in contact, the plasticiser will start to migrate and a glue-like effect will be obtained. It is also possible to use an expansion agent in the polymer sealer which will improve the elastic properties of the seal. 
     The polymer sealer  31  is primarily used for sealing the joint, thereby improving the water and moisture resistance of an installed surface comprising panels according to the invention. The assembly joining members  10 ′ and  10 ″ respectively will give the mechanical strength of the joint. 
     The joint between two joined panels  1  also comprises cavities which are formed between the surfaces of the assembled joint. These cavities will give room for any loose particles that inevitably will be present in the joint. These particles may otherwise obstruct the installation in different ways, like causing so-called proud edges locally. 
       FIG. 2  shows, in cross-section, two adjacent edges according to a second embodiment of the invention. The embodiment shows similarities with the embodiment shown in  FIG. 1 . The panels  1  are provided with a first assembly joining member  10 ′ on a male edge  2 ′ while a female edge  2 ′ is provided with a second assembly joining member  10 ″. The female edge  2 ″ is arranged on a side opposite to the male edge  2 ′. The first assembly joining member  10 ′ is provided with a lower snapping web  26  arranged on the lower side of a tongue. The lower snapping web  26  is intended to interact with a recess  27  arranged on a lower cheek  28  arranged on the second assembly joining members  10 ″ so that two joined adjacent panels  1  are locked against each other in a horizontal direction. The lower cheek  28  forms a lower surface of a groove  30  in the female edge  2 ″. 
     The joint between a male and a female edge  2 ′ and  2 ″ respectively of two joined panels  1  further comprises contact surfaces which are constituted by the lower snapping web  26  and recess  27 , the tongue  29  and groove  30  as well as upper male and female mating surfaces  25 ′ and  25 ″ respectively. These upper male and female mating surfaces  25   1  and  25 ″ respectively are provided with recesses in which a polymer sealer  31  is applied. This polymer is suitably a non-curing thermoplastic elastomeric sealant which will merge over the edge once assembled so that the two separate polymer sealers  31  will fuse over time to form one elastic seal. In order to ensure a good initial pressure over the joint between the two polymer sealers  31 , at least one of them is provided with a number of narrow, protruding lips  31 ′. These narrow, protruding lips  31 ′ will make the need of a narrow matching and manufacturing tolerance in respect of the thickness of the two polymer sealers  31  less critical. It will hereby be possible to avoid problems caused by having applied polymer sealers  31  that are too thick. This would otherwise cause problems during installation and could also cause the polymer sealers  31  to being squeezed up on top of the laminate where the abundant polymer sealer  31  is easily removed. Nevertheless, it is desired to avoid this extra operation in the installation process. It is further possible to use an expansion agent in the polymer sealer which will further improve the elastic properties of the seal. 
     The polymer sealer  31  is primarily used for sealing the joint, thereby improving the water and moisture resistance of an installed surface comprising panels according to the invention. The assembly joining members  10 ′ and  10 ″ respectively will give the mechanical strength of the joint. 
     The joint between two joined panels  1  also comprises cavities which are formed between the surfaces of the assembled joint. 
       FIG. 3  shows, in cross-section, two adjacent edges according to a third embodiment of the invention. The panels  1  are provided with a first vertical assembly joining member  10 ′ on a male edge  2 ′ while a female edge  2 ″ is provided with a second vertical assembly joining member  10 ″. The female edge  2 ″ is arranged on a side opposite to the male edge  2 ′. The first vertical assembly joining member  10   1  is provided with mainly vertical lower cheek surfaces  21  arranged parallel to the closest edge  2 . The lower cheek surfaces  21  are intended to interact with mainly vertical upper cheek surfaces  22  arranged on the second vertical assembly joining members  10 ″ so that two joined adjacent panels  1  are locked against each other in a horizontal direction. The first vertical assembly joining member  10 ′ is moreover provided with a snapping hook  23  while the second vertical assembly joining member  10 ″ is provided with a matching undercut  24 , which by being provided with mainly horizontal locking surfaces limits the vertical movement between two joined adjacent panels  1 . 
     The joint between a male and female edge  2 ′ and  2 ″ respectively of two joined panels  1  further comprises contact surfaces which are constituted by the locking surfaces of the under cuts  23  and hooks  24 , the mainly vertical upper cheek surfaces  22 , lower cheek surfaces  21  as well as upper mating surfaces  25 . 
     The joint between a male and a female edge  2 ′ and  2 ″ respectively of two joined panels  1  further comprises contact surfaces which are constituted by the lower snapping web  26  and recess  27 , the tongue  29  and groove  30  as well as upper male and female mating surfaces  25 ′ and  25 ″ respectively. These upper male and female mating surfaces  25 ′ and  25 ″ respectively are provided with recesses in which a polymer sealer  31  is applied. This polymer is suitably a non-curing thermoplastic elastomeric sealant which will merge over the edge once assembled so that the two separate polymer sealers  31  will fuse over time to form one elastic seal. It is also possible to utilise other thermoplastic elastomers where only one of the upper mating surfaces  25 ′ or  25 ″ respectively are provided with a polymer sealer  31  comprising a plasticiser while the other upper mating surface  25 ′ or  25 ″ respectively is provided with a polymer sealer  31  lacking this plasticiser. Once the panels are joined and the polymer sealer  31  of the two mating surfaces  25 ′ and  25 ″ respectively, are in contact, the plasticiser will start to migrate and a glue-like effect will be obtained. As described in connection to  FIG. 2  above it is also possible to provide at least one of the two polymer sealers  31  with one or a number of narrow, protruding lips  31 ′ in order to ensure a good initial pressure over the joint between the two polymer sealers  31 , These narrow, protruding lips  31 ′ will make the need of a narrow matching and manufacturing tolerance in respect of the thickness of the two polymer sealers  31  less critical. It is further possible to use an expansion agent in the polymer sealer which also will improve the elastic properties of the seal. 
     The polymer sealer  31  is primarily used for sealing the joint, thereby improving the water and moisture resistance of an installed surface comprising panels according to the invention. The assembly joining members  10 ′ and  10 ″ respectively will give the mechanical strength of the joint. 
     The joint between two joined panels  1  also comprises cavities which are formed between the surfaces of the assembled joint. These cavities will give room for any loose particles that inevitably will be present in the joint. These particles may otherwise obstruct the installation in different ways, like causing so-called proud edges locally. 
     It is according to a special embodiment of the invention possible to use one type of joint on two of the edges  2 , arranged on opposite sides, while remaining, adjacent edges  2  are provided with a second type of joint. It is accordingly possible to use the joint shown in figure one or two on the long side edges  41  of a rectangular panel  1  (see  FIG. 5 ), while the short side edges  42  are provided with a joint as shown in figure three. It is of course also possible to use the same type of joint on all edges  2  of the panel  1 . The panel  1  may of course also have other shapes than being rectangular. 
       FIGS. 4 a , 4 b  and 4 c    shows, in cross-section, a special embodiment of the invention.  FIG. 4 a    shows two adjacent edges before assembly while  FIGS. 4 b  and 4 c    shows the same edges assembled. The embodiment shows similarities with the embodiment shown in  FIG. 1 . The panels  1 , as best viewed in  FIG. 4 a   , are provided with a first assembly joining member  10 ′ on a male edge  2 ′ while a female edge  2 ″ is provided with a second assembly joining member  10 ″. The female edge  2 ′ is arranged on a side opposite to the male edge  2 ′. The first assembly joining member  10 ′ is provided with a lower snapping web  26  arranged on the lower side of a tongue. A web recess  26 ′ is located behind the lower snapping web  26 . The lower snapping web  26  is intended to interact with a recess  27  arranged on a lower cheek  28  arranged on the second assembly joining members  10 ″ so that two joined adjacent panels  1  are locked against each other in a horizontal direction. The lower cheek  28  forms a lower surface of a groove  30  in the female edge  2 ″. A flexible insert  27 ′ is located in the recess  27 . This flexible insert  27 ′ is located between the recess  27  and the lower snapping web  26  and will allow a limited movement in horizontal direction between the panels. The web recess  26 ′ will leave space for the flexible insert  27 ′ to bulge out when being compressed. 
     The joint between a male and a female edge  2 ′ and  2 ″ respectively of two joined panels  1  further comprises contact surfaces which are constituted by the lower snapping web  26  and recess  27 , the tongue  29  and groove  30  as well as upper male and female mating surfaces  25 ′ and  25 ″ respectively. These upper male and female mating surfaces  25 ′ and  25 ″ respectively are provided with recesses in which a polymer sealer  31  is applied. This polymer, which suitably also is used when manufacturing the flexible insert  27 ′, is suitably a non-curing thermoplastic elastomeric sealant which will merge over the edge once assembled so that the two separate polymer sealers  31  will fuse over time to form one elastic seal. In order to ensure a good initial pressure over the joint between the two polymer sealers  31 , at least one of them is provided with a number of narrow, protruding lips  31 ′. These narrow, protruding lips  31 ′ will make the need of a narrow matching and manufacturing tolerance in respect of the thickness of the two polymer sealers  31  less critical. It will hereby be possible to avoid problems caused by having applied polymer sealers  31  that are too thick. This would otherwise cause problems during installation and could also cause the polymer sealers  31  to being, squeezed up on top of the laminate where the abundant polymer sealer  31  is easily removed. Nevertheless, it is desired to avoid this extra operation in the installation process. It is further possible to use an expansion agent in the polymer sealer which will further improve the elastic properties of the seal. 
     The polymer sealer  31  is primarily used for sealing the joint, thereby improving the water and moisture resistance of an installed surface comprising panels according to the invention. The assembly joining members  10 ′ and  10 ″ respectively will give the mechanical strength of the joint. 
     The polymer sealer  31  together with the flexible insert will allow a limited movement between two adjacent panels  1  with a maintained seal protecting from penetration of moisture. The amount of movement allowed is easily adjusted through the dimensions of the recess  27 , polymer sealer  31  and flexible insert  27 ′. It is advantageous to use the invention as described in connection to  FIG. 4 a - c    on for example floor boards where the core material is made of a wood based material like fibre board, particle board, chip board, oriented strand board or massive wood. It is common knowledge among artisans that wood based materials will expand and contract depending on moisture content. This implies that a floor will be smaller in winter time when the moisture content in air at room temperature is lower than in late summer when the moisture content is high. This is observed by most people during the winter time when gaps often occur in wood flooring. The invention as described in connection to  FIG. 4 a - c    will absorb this moisture propelled expansion and contraction. Typically around 1 mm per meter of floor will be more than enough to absorb. As one typical width of floor panels is 200 mm a sufficient movement allowed in a long side edge joint would be around ±0.1 mm. It is possible to use the joint described in  FIG. 4 a - c    only on the long sides, the short sides or on all sides. It is also possible to use the herein described device on special places like doorways and the like or on every other or every third row of panels. 
     Referring now to  FIG. 4 b    showing the assembled panels  1  from  FIG. 4 a   . The joint is in a stretched state in  FIG. 4 b   . This is the typical state the joint will be in during longer periods of very dry conditions. The flexible insert  27 ′ is compressed while the polymer sealer  31  is slightly stretched. 
     Referring now to  FIG. 4 c    showing the assembled panels  1  from  FIG. 4 a   . The joint is in a compressed state in  FIG. 4 c   . This is the typical state the joint will be in during longer periods of very humid conditions. The flexible insert  27   1  is unloaded while the polymer sealer  31  is compressed. 
     The joint shown in  FIG. 4 a - c    will make normal dilation devices abundant and will make it possible to achieve door passages and very large surfaces without having to use any dilation devices. 
     The visible part of the polymer sealer can be dyed or lacquered to match the floor surface or to create any desired accent. It is also possible to provide it with a thin flexible foil or laminate provided with a printed decor. It is furthermore possible to provide the visible part of the polymer sealer with a printed decor directly on top of the visible surface. One known method for achieving this is the method of transfer printing. It is furthermore advantageous to at least blunt the edges of the upper surface closest to the polymer sealer. 
     It is also possible to provide the joint as shown in  FIG. 3  with a flexible insert  27 ′ to achieve flexibility in this joint as well. This flexible insert  31 ′ is then suitably arranged on the mainly vertical upper cheek surfaces  22 . 
     The invention is not limited by the embodiments shown since these can be varied in different ways within the scope of the invention.