Abstract:
The present invention provides a structural element for the construction of log type houses. The structural element comprises structural portions, preferably made of aluminum, and insulating material. The insulation coefficient of the structural element may be adapted to the local climate. Furthermore, the structural element is less sensible to temperature and humidity variations than wood, preventing possible cracks to appear between adjacent structural elements.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present patent application claims the benefits of priority of commonly assigned Canadian Patent Application No. 2,631,455, entitled “Structural Element for the Construction of Log Type Houses” and filed at the Canadian Intellectual Property Office on May 16, 2008. 
       FIELD OF THE INVENTION 
       [0002]    The present invention generally relates to structural elements, and more particularly to a structural element for the construction of log type houses. 
       BACKGROUND OF THE INVENTION 
       [0003]    Conventional building techniques, featuring, for example, wood frame, precast and/or concrete block construction are relatively complicated and labor intensive. As a result, construction costs continue to escalate. 
         [0004]    Traditional log homes remain popular as an alternative to more common building techniques. Nonetheless, wood log construction can also be intricate and time consuming. The individual logs must be precisely cut and shaped. Often a considerable amount of material is wasted in the construction process. The configurations and layouts available using log construction are also quite limited. And because traditional log homes are composed of wood, they are very susceptible to fire damage. 
         [0005]    Log homes have been in existence and common use for centuries. Originally, log cabins were built in wooded areas where there was a large supply of wooden logs from trees. Because log homes are still considered versatile, energy efficient structures, many modern improvements have been made to the log home. The majority of the improvements attempt to minimize the amount of labor involved in erecting a log home while improving the overall integrity of the structure. 
         [0006]    A problem with the structures disclosed above is that most of them require a great deal of on-site construction and labor. In the areas where log homes are very popular, the weather tends to limit the amount of building time available in a given year. Another disadvantage is that many of those structures do not use real wood logs, but instead use building panels that simulate the appearance of a log home. Therefore, what is needed is a structural element that may be prefabricated and that do not need any special or unusual skills or tools to construct a log house or the like. 
       OBJECTS OF THE INVENTION 
       [0007]    A first object of the present invention is to provide a structural element for the construction of a log house or the like. 
         [0008]    A second object of the present invention is to provide a structural element which is prefabricated and inexpensive. 
         [0009]    A third object of the present invention is to provide a structural element with which it is easy to construct a log house or the like with no need to use special tool or with no need to have unusual skills. 
         [0010]    Other and further objects and advantages of the present invention will be obvious upon an understanding of the illustrative embodiments about to be described or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice. 
       SUMMARY OF THE INVENTION 
       [0011]    The aforesaid and other objectives of the present invention are realized by generally providing an insulated structural element for the construction of log like houses or the like, the structural element having a cross-section, the structural element being adapted to be disposed one on top of another one, the cross-section of the preferred structural element comprising a L-shaped top surface, a L-shaped bottom surface, a first portion extending between the top surface and the bottom surface, a second portion extending between the top surface and the bottom surface and wherein the cavities formed by the top surface, the bottom surface, the first portion and the second portion are filled with an insulating material. 
         [0012]    The structural element of the present invention is used to construct walls of log houses or the like. As used herein, the word ‘log’ refers to any structural element having a general configuration which is log like and not limited to logs made of wood. The structural elements are disposed one on top of other as usually seen in log houses. The log like structural element comprises structural portions and insulating material. The insulation coefficient of the structural element of the present invention may be adapted to a plurality of climate by varying the insulation properties of the insulating material. This is a notable advantage compared to logs made from wood, more particularly in extreme climates to control the internal temperature of the log house. Indeed, in colder climates such as in the northern parts of America and Europe, a higher insulation coefficient may be choosen. 
         [0013]    Another advantage is that the structural element of the present invention is not as sensible as a wood log to the variations of volume following the variations of temperature and of humidity rates. This minimizes the risk of openings or cracks that appear between adjacent logs thus improving the insulation properties of the log house. 
         [0014]    To provide good structural properties to the wall of the log house, internal portions may be added into the structural element. For example, the structural element may further comprises a third portion and a fourth portion extending from the bottom surface and the top surface, the upward extremities of the third portion and the fourth portion being perpendicular to the top surface. Other examples are detailed in the preferred embodiment section and are not limited to these examples. The internal portions are made preferably from the same material as the external portions. External portions are preferably made from aluminum because it is light and easy to shape but other materials may be used. The different portions may be glued together or welded to improve the structural integrity of the structural element. 
         [0015]    The insulating material is preferably a foam type so that the structural has good insulating properties and is still light weighted. The foam may be of the expandable foam type such as, for example, urethane. The foam may also be provided in block form, the blocks having a shape that is complementary to the cavities of the structural element and that are inserted into the structural element. 
         [0016]    The structural element may be made by folding a metal sheet or by assembling a plurality of portions together. In both case, the structural element may be welded or glued at the junction of different portions. The structural element may also be made by forming a tubular section in which sections may be inserted to improve the structural integrity. The structural element may also be extruded. There are many glues available for metals, and more particularly for aluminum there are glues in the family of, for example, epoxy (ex: Hysol™), polyurethane, acrylic, or silicon. 
         [0017]    Problems with thermal bridges can be readily overcome or minimize by using methods known in the art. One example is detailed in the preferred embodiments section. 
         [0018]    Because the structural element is constructed, it is possible to create almost any profile, such as rounded-like logs. The structural element may comprise built-in clapboard so the external look of the log house is different from the log house type. 
         [0019]    It is also possible to laminate actual wood strips onto the outside of the structural elements to create a wood log appearance. 
         [0020]    It is very easy to construct a log house with the structural element of the present invention. There is no need to have the unusual skills or tools usually needed for the construction of log house because the structural elements are ready to use and just have to be installed one on top of the others. 
         [0021]    The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The above and other objects, features and advantages of the invention will become more readily apparent from the following description, reference being made to the accompanying drawings in which: 
           [0023]      FIG. 1  is a cross-sectional view of a first embodiment of the present invention. 
           [0024]      FIG. 2  is a top view of the metal sheet used which is folded to create the structural element of the embodiment shown in  FIG. 1 . 
           [0025]      FIG. 3  is a perspective view of the embodiment shown in  FIG. 1 . 
           [0026]      FIG. 4  is a cross-sectional view of a variation of the embodiment shown in  FIG. 1 , wherein the sides of the structural element are rounded. 
           [0027]      FIG. 5  is a cross-sectional view of the a variation of the embodiment shown in  FIG. 1 , where the structural element further comprises a clapboard. 
           [0028]      FIGS. 6 and 7  are a front view and a perspective view of an end cap. 
           [0029]      FIG. 8  is cross-sectional view showing another embodiment of the present invention. 
           [0030]      FIG. 9  is cross-sectional view showing another embodiment of the present invention. 
           [0031]      FIG. 10  is a schematic view illustrating a method to construct or produce the structural element of the present invention by press-forming. 
           [0032]      FIG. 11  is a perspective view of an embodiment of the structural element. 
           [0033]      FIG. 12  is a top view showing the metal sheet used to construct or produce the embodiment of the structural element shown in  FIG. 11 . 
           [0034]      FIGS. 13   a  to  13   c  are a front view and two perspective views, respectively, showing a method to construct or produce the structural element of the present invention. 
           [0035]      FIG. 14   a  is a side view showing the structural element. 
           [0036]      FIG. 14   b  is a perspective view showing the structural element of the present invention with an end cap. 
           [0037]      FIG. 15  is a perspective view showing structural elements as used to construct a wall. 
           [0038]      FIG. 16  is a perspective view showing a structural element on which a strip of wood laminate is applied. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0039]    A novel structural element will be described hereinafter. Although the invention is described in terms of specific illustrative embodiment(s), it is to be understood that the embodiment(s) described herein are by way of example only and that the scope of the invention is not intended to be limited thereby. 
         [0040]      FIG. 1  illustrates the structural element of the present invention. The structural element has a generally L-shaped element with a top surface  120  and a bottom surface  122 , the top surface  120  and the bottom surface  122  are L-shaped and are connected by two portions, a first portion  160  and a second portion  162  extending between them. The structural element is adapted to be disposed on the top of another structural element, the top surface  120  and the bottom surface  122  having a complementary shape. 
         [0041]    A vertical portion  105  extends between the top surface  120  and the bottom surface  122 . A third portion  110  and a fourth portion  112  extend between the top surface  120  and the bottom surface  122 , their upward extremities being perpendicular to the top surface  105 . The cavities  132 ,  134 ,  136  and  138  are filled with an insulating material (not shown). 
         [0042]    The embodiment shown in  FIG. 1  may be made by folding the metal sheet shown in  FIG. 2 . The metal sheet  200  is folded along the horizontal lines illustrated in  FIG. 2  to create the structural element of  FIG. 1 . Glue may also be applied where the surfaces of the metal sheet are in contact ( 150 ,  152 ,  154 ). 
         [0043]    The  FIG. 4  shows an embodiment similar to the one presented in  FIG. 1 , except that the sides are rounded, providing a different look. The structural element is preferably welded along its length at the intersection of the different portions such as indicated by the welding cords  142 ,  144 ,  146  and  148 . 
         [0044]    In  FIG. 5 , a clapboard portion  210  is added to the structural element to give another look. The clapboard portion  210  illustrated is shown as being vertical once installed but it may be oriented differently. The clapboard portion  210  is preferably integral to the structural element although it could be an add-on made of the same or different material as the structural element. It could even be made out of real wood. 
         [0045]      FIGS. 6 and 7  show an end cap used to cover the extremities of the structural element. The end cap has a shape that is complementary to the shape of the cooperating structural element. The end cap may be fixed to the structural with, for example, glue or be welded to it. The lines illustrated  280  on the end cap may be added to simulate a wood beam. 
         [0046]    In  FIGS. 8 and 9 , transversal portions are added to the structural element. In  FIG. 8 , substantially horizontal portions  202  and  204  are extending between the top surface  120  and the bottom surface  122 . In  FIG. 9 , there are vertical portions  206  and  208  extending between the top surface  120  and the bottom surface  122 . 
         [0047]      FIG. 10  illustrates another method to produce the structural element of the present invention. The tube  300  is pressed to obtain the desired external shape of the structural element  302 . The internal portion  304  is then inserted in the external portion  300  and preferably welded to it as shown by the welding cords  310 ,  312 ,  314  and  316 . The internal portion  302  illustrated may be composed by a plurality of parts. These parts may be assembled and welded before they are inserted in the external portion or after. It is to be understood that it is possible to have other configurations for the internal portion. 
         [0048]      FIG. 12  shows another embodiment of the present invention. The structural element  352  is made by folding a metal sheet  350  shown in  FIG. 11  along the horizontal lines. The structural element  352  is preferably welded as shown by the welding cords  360 . 
         [0049]    In  FIGS. 13   a  to  13   c,  another method is shown for the construction of the structural element. The structural element  406  is made from a first part  402  and a second part  404 . To minimize problems caused by thermal bridges, non-conductive elongated parts  420  and  422  are fixed to the second part  404 . The elongated parts  420  and  422  are made from a material such as polyamide, for example, and may be reinforced with fibreglass. Receiving elongated parts  424  and  426 , adjacent to the first part  402 , are adapted to receive the elongated parts  420  and  422 . Prior to join the first part  402  to the second part  404 , an adhesive is applied on the elongated parts  420  and  422  and/or (depending of the instructions for the adhesive used) on the receiving elongated parts  424  and  426 . As previously mentioned in the summary, the adhesive may be, but not limited to, an epoxy or polyurethane. The receiving elongated parts  424  and  426  may be added to the first part  402  or may be unitary with the first part  402 . As shown in  FIG. 13   c,  the thermal flux is stopped or minimized at the junctions  410  and  412  of the elongated parts  420  and  422  and the receiving elongated parts  424  and  426 . 
         [0050]    The structural element shown in  FIGS. 14   a,    14   b  and in  FIG. 15  comprises two inverted ‘V’ notches  502  and  504  allowing the structural elements to be disposed one on the other. Indeed, the notches  502  and  504 , which are transversal, have a shape which is complementary to the shape of the top surface  510  of the structural element  500 . The notches may be done by, for example, sawing the structural element to create the desired shape for the notches. The structural element  500  of  FIG. 14   a  and  14   b  comprises an end cap  154 . When the structural elements are stacked one on the other, to seal the opening made by sawing the structural element, a seal joint may be add between adjacent structural elements. The openings could also be sealed prior to be assembled by applying a layer of sealing material such as epoxy. In an other embodiment, a plate having a complementary shape is welded to the structural element, closing the opening created by sawing the notches. 
         [0051]    The structural element  525  shown in  FIG. 16  is covered by a strip of wood laminate  530 . The strip of wood laminate  530  is fixed on the structural element  525  with methods known in the art, such as with an adhesive adapted for wood laminate and aluminum (for a structural element made of aluminum). 
         [0052]    While illustrative and presently preferred embodiment(s) of the invention have been described in detail hereinabove, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art.