Abstract:
The present disclosure concerns roof racks made substantially of cardboard or plastic, systems for carrying cargo onto a car&#39;s roof comprising such roof racks, kits for constructing such roof-rack systems and methods of installing such roof-racks onto a roof of a car.

Description:
TECHNOLOGICAL FIELD 
       [0001]    The present invention concerns roof racks, e.g. made substantially of plastic or cardboard. 
       BACKGROUND ART 
       [0002]    References considered to be relevant as background to the presently disclosed subject matter are listed below:
       WO 10/024754   WO 97/49574   US 2010/0230452   U.S. Pat. No. 8,534,516   AU 2002300174       
 
         [0008]    Acknowledgement of the above references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter. 
       BACKGROUND 
       [0009]    Roof racks are typically mounted onto the roof of a car and are used for carrying over-sized cargo during transportation. Often, these roof racks need to be fixedly installed onto the car&#39;s roof and the type and geometry of the carrier is typically unique to each car model or manufacturer. 
         [0010]    As such custom installation is often costly and complex, car owners do not typically install such carriers, and often find themselves in situations which require the use of such carriers. Several portable roof rack systems are known, most of which are such that are structured from rigid foams (see, for example WO 10/024754, U.S. Pat. No. 8,534,516 and AU 2002300174) or metal-made foldable systems (for example of the type described in US 2010/0230452). Such systems, however, are often voluminous and therefore problematic for storage in a car-trunk when not in use. Other known systems comprise flexible structures that need to be inflated prior to use (such as those described, for example, in WO 97/49574), often requiring the use of compressed air. 
         [0011]    Therefore, there is a need for a versatile carrier, which will be suitable for installation on the roof of different car models that is easily constructed, installed onto and detached from the car&#39; roof by the user when needed, and conveniently stored when not in use. 
       GENERAL DESCRIPTION 
       [0012]    The present disclosure provides a disposable and/or recyclable roof-rack system, comprising weight-supporting structures which are made substantially of cardboard or plastic. The weight-supporting structures are formed out of cardboard or plastic sheets, typically by folding each of the elements of the structure from a single, pre-shaped, sheet of cardboard or plastic, followed by simple assembly of the elements to form the weight-supporting structure. The present disclosure thus provides a roof rack that is quickly and simply assembled by the user, does not require any custom installation, and may be conveniently removed from the car&#39;s roof and disposed-of or recycled after usage. 
         [0013]    Thus, in one of its aspects, this disclosure provides a weight-supporting structure, that comprises (i) a crossbar that defines a longitudinal axis, and (ii) at least one first and one second generally prismatic support elements. As noted, each of the crossbar and the prismatic support elements may be made substantially out of cardboard or plastic. 
         [0014]    In some embodiments, the crossbar is made of cardboard and the prismatic support elements may be made of plastic. In other embodiments, the crossbar is made of plastic and the prismatic support elements may be made of cardboard. In some other embodiments, the crossbar and the prismatic support elements may be made of cardboard or plastic. 
         [0015]    Each of the first and second prismatic support elements has (i) a planar internal member that defines a vertical plane, the plane separating the support element into substantially mirror-image longitudinal units, said internal member being vertically oriented and normal to said longitudinal axis, and (ii) an opening. 
         [0016]    The crossbar comprises at least two longitudinal beam elements, each of which having a top edge. The top edges of the beams are adjacent one another, and the beams are arranged so as to define a longitudinal prismatic gap between them. The crossbar is slidably received in the openings of the first and second prismatic support elements, to thereby form the weight-supporting structure. 
         [0017]    Without wishing to be bound by theory, the weight-supporting structure is designed to bear and distribute compression loads applied from the top side of the structure. Therefore, when loading a top surface of the prismatic support elements, part of the load is borne (i.e. supported) by the planar internal member, while another part of the load is distributed via the prismatic structure and channeled to the crossbar. The shape of the crossbar allows distribution of the load transferred from the support elements, i.e. from the top edge of the crossbar to bottom edges of the beam members. 
         [0018]    In some embodiments, each of the support elements has a generally rectangular cross-section or a trapezoid cross-section, typically an inverted-trapezoid cross section. Each of the first and second support elements has a top surface and a bottom surface, which, in some embodiments, are dimensioned so that the top surface has an area larger than the area of the bottom surface. 
         [0019]    According to some embodiments, each of the mirror-image longitudinal units has a prismatic cross-section. Within the context of the present disclosure, the term prismatic denotes a closed shape formed of 3 or 4 sides perpendicular to an imaginary 3- or 4-sided polygonal base, such that a cross-section parallel to the imaginary base is of triangular, rectangular or trapezoid form. 
         [0020]    In some embodiments, each of the mirror-image longitudinal units has a right-angle (about 90°) trapezoid cross-section. Typically, the mirror-image longitudinal units are adjacent one another, thereby forming the planar internal member. 
         [0021]    According to some embodiments, each of said prismatic support elements is formed out of a single sheet of cardboard or plastic. 
         [0022]    According to some other embodiments, each of the support elements may be formed by folding a single sheet of cardboard or plastic. 
         [0023]    The term cardboard is meant to encompass a paper product that comprises (i) at least one low-density layer made of paper, heavy duty paper or cardboard (for ease of reference the term paper, will be used hereinafter to refer collectively to paper, heavy duty paper or cardboard) arranged to define a plurality of cells or voids, e.g., formed by corrugated, fluted or otherwise loosely packed paper sheets or strips that define a plurality of voids there between, and comprising (ii) one or more liner cardboard sheets lined at one side or both sides of the low-density layers (namely sandwiching the low-density layer between them). Examples of such cardboard panels are such known as corrugated (or fluted) cardboard, which consists of a fluted or corrugated paper panel(s) or strip and one or two flat linerboards at one or both (i.e. sandwiching) sides of the fluted or corrugated paper; and may also be such referred to as honeycomb cardboard. Such materials are widely used in the manufacture of boxes and shipping containers. The corrugated or honeycomb cardboard panels may be single-walled or multi-walled cardboard panel. These terms are also meant to encompass heavy-duty cardboard of various strengths, ranging from a simple arrangement of a single thick panel of paper to complex configurations featuring multiple corrugated, honeycomb and other layers, or fiber-reinforced cardboard. 
         [0024]    The term plastic is meant to encompass a polymeric-based product. A plastic sheet used for construction of the weight-support structure may be a solid plastic sheet (i.e. a sheet having a uniform density along its entire cross-section), or a corrugated, fluted or honeycombed plastic sheet (i.e. a sheet in which a plurality of directional voids are defined), as well as fiber-reinforced plastic. 
         [0025]    It is also contemplated that where the weight-supporting structure is made of cardboard, different types of cardboard may be utilized to form the various elements of the structure. Namely, the crossbar may be formed from one type of cardboard, e.g. corrugated cardboard, while the support elements may be made of another type of cardboard, e.g. heavy duty cardboard. Similarly, where the weight-supporting structure is made of plastic, different types of plastic sheets may be utilized to form the various elements of the structure. 
         [0026]    The term sheet, whether referring to a cardboard or a plastic sheet, means a planar or substantially planar piece of material with a broad surface that is substantially thin as compared to its length and width. The sheet may be a uniform piece but may also, for example, be made of two or more planar pieces glued or otherwise adhered together to form a larger and/or thicker sheet that is formed into the structure&#39;s different components. 
         [0027]    The various elements of the structure may be formed out of a cardboard or plastic sheet having a uniform thickness; however it is also possible that the crossbar will be formed from a sheet having a first thickness, while the support elements will be formed out of a sheet having a second, different thickness. 
         [0028]    The term formed (or any of its linguistic variations) means to denote the act of giving form or shape to the cardboard or plastic sheet, namely forming the sheet into a final element in the structure. Such forming comprises, for example, folding the sheets into the shape of the elements. 
         [0029]    The first and second beam elements may, by some embodiments, be integral with each other. 
         [0030]    The term integral means that the sheet portions that are used in the formation of the crossbar are all portions of a single, formed sheet. Thus, by some embodiments, the crossbar is formed out of a single sheet of material, such that the two beam elements are integral one with the other. Typically, the crossbar is formed by folding a single sheet of cardboard or plastic. 
         [0031]    In order to provide versatility in installation, the each of said first and second prismatic support elements may, by some embodiments, be slidably displaceable along the crossbar&#39;s longitudinal axis. This allows a user to adjust the distance between the prismatic support elements according to the dimensions and curvature of the car&#39;s roof. 
         [0032]    In a structure of this disclosure, the crossbar may comprise cardboard or plastic having longitudinal hollow channels or longitudinal hollow flutes (e.g. corrugated cardboard or corrugated plastic). By some embodiments, the longitudinal hollow channels or longitudinal hollow flutes are parallel to the longitudinal axis of the crossbar. 
         [0033]    The weight-supporting structure may further comprise at least one coating layer, which may be, for example, a liquid impermeable coating layer, a water-repelling coating layer, a paint layer, and others. The outer surface of the structure may be printed with different labels, barcodes, textures, etc. 
         [0034]    In some embodiments, the weight-supporting structure may further comprise means for increasing the friction between the support (i.e. prismatic) elements and the rood of the car once the roof-rack is mounted onto car&#39;s roof, as explained further below. 
         [0035]    According to some embodiments, the weight-support structure of this disclosure is capable of supporting a weight of at least 20 Kg/44 lbs, at least 50 Kg/110 lbs., or even at least 75 Kg/165 lbs. 
         [0036]    In another aspect, there is provided a system for carrying cargo on a car&#39;s roof, the system comprises a weight-supporting structure as described herein, and attachment means for attaching the weight-supporting structure to the car&#39;s roof. In some embodiments, the system may comprise at least two weight-supporting structures and a corresponding number of attachment means (e.g. at least two such means). 
         [0037]    In some embodiments, the attachment means permits detachable fitting of the weight-support structure to the roof of the car, i.e. the attachment means does not require custom installation onto the car&#39;s roof. Non-limiting examples of such attachment means are a ratchet belt, a lashing belt, a lashing strap, a strap with fasteners (or buckles), a lashing strap fitted with hooks, etc. 
         [0038]    The attachment means is, by some embodiments, fitted through the longitudinal prismatic gap defined between the beam elements of the crossbar. In other embodiments, the attachment means is associated with (i.e. adhered, glued) to a one of the surfaces defining said longitudinal prismatic gap. 
         [0039]    In order to fasten the cargo onto the weight-supporting structures, the system may, by some embodiments, further comprise additional strapping means. The additional strapping means are typically, but not exclusively, fitted through the longitudinal prismatic gap defined between the beam elements. 
         [0040]    In another aspect, the present disclosure provides a kit for constructing a roof-rack system to be attached onto a roof of a car, the kit comprising at least one first sheet having a first set of fold lines, the first sheet being shaped for folding into a crossbar, such that when folded, the crossbar defines a longitudinal axis, and comprises at least two longitudinal beam elements, each of which having a top edge, the top edges of the beams being adjacent one another, the beams being arranged so as to define a longitudinal prismatic gap between them; at least two second sheets having a second set of fold lines and a set of cut-outs, each being shaped for folding into a prismatic support element, such that when folded, (i) the prismatic support element having a planar internal member defining a vertical plane separating the support elements into substantially mirror-image longitudinal elements, said internal member being vertically oriented and normal to said longitudinal axis, and (ii) the cut-outs are aligned to form an opening in each of the prismatic support elements for slidably receiving said crossbar; and optionally comprises attachment means. The first and second sheets being made of cardboard or plastic. 
         [0041]    The folding lines in the sheets may, by some embodiments, be constituted by perforations patterned in line forms, line areas of a reduced thickness, line areas formed out of non-reinforced cardboard or plastic, pre-stressed line areas, etc. 
         [0042]    The kit may further comprise instructions for use, which may typically, though not exclusively, be printed onto the surface of the sheets. 
         [0043]    In other embodiments, the kit may further comprise means for increasing the friction between the support elements and the rood of the car once the weight-support structure is mounted onto car&#39;s roof. Such means may include, for example, stickers having an external surface designed for increasing the friction between the support elements and the car&#39;s roof, which may be applied to the bottom surface of the support elements that comes into contact with the car&#39;s roof. In another example, the friction-increasing means are an integral part of the second sheets, from which the support elements are folded, and positioned such that once folded into its final shape, the friction-increasing means will be integral with the surface of the support elements that is designed to come into contact with the car&#39;s roof. 
         [0044]    In some embodiments, the weight-supporting structure is disposable. In other embodiments, the weight-supporting structure is recyclable. In further embodiments, the weight-supporting structure may be unfolded after use for ease of storage. 
         [0045]    According to another aspect, there is provided a method of installing a roof-rack onto a roof of a car, the method comprising:
       providing a weight-supporting structure as herein described;   providing an attachment means for attaching the weight-supporting structure to the car&#39;s roof;   fitting the attachment means through the longitudinal prismatic gap formed in the weight-supporting structure;   positioning the weight-supporting structure onto the car&#39;s roof; and   fastening the attachment means to the car&#39;s roof.       
 
         [0051]    A further aspect provides a method of installing a roof-rack onto a roof of a car, the method comprising:
       providing a kit as herein described;   folding said first sheet along the first set of fold lines to form said crossbar;   folding each of said second sheets along the second set of fold lines to form said prismatic support elements;   sliding the crossbar into the openings formed in the prismatic support elements to form said weight-supporting structure;   fitting an attachment means through the longitudinal prismatic gap formed in the weight-supporting structure;   positioning the weight-supporting structure onto the car&#39;s roof; and   fastening the attachment means onto the car&#39;s roof.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0059]    In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: 
           [0060]      FIG. 1  shows a system according to an embodiment of this disclosure, installed onto a car&#39;s roof. 
           [0061]      FIG. 2A  is an isometric view of a weight-supporting structure according to an embodiment of this disclosure. 
           [0062]      FIG. 2B  shows an attachment means for attaching the weight-supporting structure of  FIG. 2A  to the car&#39;s roof. 
           [0063]      FIG. 3  is a side view of the structure of  FIG. 2A  from the direction noted by arrow III. 
           [0064]      FIG. 4  is a side view of the structure of  FIG. 2A  from the direction noted by arrow IV. 
           [0065]      FIGS. 5A-7  show the folding sequence for constructing the structure of  FIG. 2A  according to an embodiment of this disclosure. 
           [0066]      FIGS. 8A-8C  show the mounting sequence of a structure of  FIG. 2A  onto a car&#39;s roof. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0067]    Turning to  FIG. 1 , two weight-supporting structures  100  are shown, installed onto a roof  10  of a car  20 . As will be further explained below, the weight-supporting structures  100  are positioned on the car&#39;s roof and held in place by attachment means  200 , which are fitted through the weight-supporting structures. Although only two weight-supporting structures are shown in  FIG. 1 , it is contemplated that more than two structures may be used, typically depending on the weight of the cargo  30  to be carried and supported, as well as the dimensions of the car&#39;s roof. 
         [0068]    As noted above, the weight-supporting structures may be made of cardboard, plastic or a combination thereof. An example may be corrugated cardboard or corrugated plastic. 
         [0069]      FIG. 2A  shows in detail the weight-supporting structure  100 . The weight-supporting structure comprises a crossbar  102  and two prismatic support elements,  104  and  106 . As noted above, the crossbar and the prismatic support elements are made substantially out of cardboard or plastic, and are each typically formed, as will be explained further below, out of a single folded sheet of material (i.e. cardboard or plastic). 
         [0070]    Each of the support elements  104  and  106 , includes a planar internal member  108  and  110 , respectively, as can also be seen in  FIG. 3  (showing the view from the direction of arrow III). Each of the planar internal members  108  and  110  defines a vertical plane separating each of the support elements  104  and  106  into substantially mirror-image longitudinal units  104   a,    104   b  and  106   a,    106   b  respectively. The planar internal members  108 ,  110  function to support a part of the mechanical load exerted by the cargo to be supported, while another part of the load is transferred to the crossbar, as will be explained below. As can be better seen in  FIG. 3 , the internal members  108  and  110  are substantially parallel to one another, and are both normal to a longitudinal axis  112  defined by the crossbar  102 . Openings  114  and  116  are formed in each of the support elements  104  and  106 , respectively, and are dimensioned to be slightly larger than the cross section dimensions of the crossbar, such that the crossbar may be slidably fitted through the openings, to form the weight-supporting structure. 
         [0071]    It is of note that the slight difference is dimensions between the cross-section of the crossbar and the dimensions of the openings  114 ,  116  allows for a snug fit of the crossbar into the support elements while maintaining a degree of freedom to change the distance between the support elements to afford versatility and adaptability to different roof dimensions and configurations. 
         [0072]    By some embodiments, shown in  FIGS. 2A and 3 , each of the support elements has an inverted trapezoid shape, having a generally planar upper surface  118  and a generally planar bottom surface  120 . The upper and bottom surfaces  118 ,  120  are parallel one to the other. The surface area of upper surface  118  is larger than the area of the bottom surface  118 , to allow support of the mechanical load applied by the cargo baggage weight, and its efficient transfer to the car&#39;s roof and the crossbar. It will be appreciated by a person of skill that the support elements may also have different cross-sectional shapes, such as rectangular or trapezoid. 
         [0073]    As can also be seen in  FIG. 4  (which is a view of the weight-supporting structure from the direction of arrow IV), crossbar  102  comprises two longitudinal beam elements  122 ,  124 , each of which having a top edge  126  and  128 , respectively. The top edges  126  and  128  of the beams are adjacent one another, and the beams are arranged, i.e. angled one versus the other, so as to define a longitudinal prismatic gap  130  between them. Each of the beam elements  122 ,  124  typically have a generally triangular cross-section. The arrangement of the beams one with respect to the other allows for efficient load distribution exerted from the direction of the top edges, once the weight-supporting structure is loaded with luggage/baggage/cargo to be carried. 
         [0074]    In order to affix the weight-supporting structure onto a roof of a car, attachment means are used, such as that shown in  FIG. 2B . The exemplary attachment means  200  shown in  FIG. 2B  includes a strap  202  and fastening means  204  at one or both edges of the strap. For attaching the weight-support structure onto the car&#39;s roof, a user slides the strap  202  through the longitudinal prismatic gap  130  formed in the weight-support structure, leaving both ends of the strap to hang out of the ends of gap  130 . After positioning the weight-support structure in the desired position, i.e. across the width dimension of the car&#39;s roof (as can also be seen in detail in  FIGS. 8A-8C ), the edges of the strap are passed through the car&#39;s open windows, then the fastening means  204  are connected in order to apply tension onto the strap. In some embodiments, the attachment means is in the form of a ratchet belt, allowing adjustment of the tension applied onto the strap. 
         [0075]    The weight-support structure may be stored in a flat-pack prior to use. When required, the weight-support structure can be assembled by simply folding each of the structure&#39;s elements into shape, followed by assembling the weight-support structure.  FIGS. 5A-5E, 6A-6D and 7  show the sequence of folding and assembling of the crossbar, the support elements and the weight-support structure, respectively. 
         [0076]    As can be seen in  FIGS. 5A-5C , the crossbar may be formed from a single sheet of cardboard or plastic  300 , onto which a set of fold-lines is formed. The user first folds sections  302  about fold-line  304 , as shown by arrows  306  ( FIG. 5A ). Another fold is then made along fold-lines  308  in the direction of arrows  310  ( FIG. 5B ), followed by another fold along fold-lines  312  in the direction of arrows  314  ( FIG. 5C ). These folding actions result in the formation of the two beam elements  122 ,  124 , which are then folded about fold-lines  316  in the direction of arrows  318  ( FIG. 5D ), to bring edges  126  and  128  of the beams adjacent one, thereby forming the crossbar ( FIG. 5E ). 
         [0077]    Each of the prismatic support elements is formed out of a single sheet of cardboard or plastic, as can be seen in  FIGS. 6A-6D . The following description will relate to the formation of prismatic support element  104 , however it is to be understood that the formation of prismatic support element  106  is carried out similarly. Sheet  400  is pre-formed with cut-outs  402 . The cut-outs are designed to match the shape of the crossbar&#39;s cross-section, and are dimensioned to be slightly larger than the crossbar&#39;s cross-section, in order to allow the crossbar to be slidably fitted into openings. The cut-outs the may be such that are hollow, or may be pre-punched into the sheet such that a user needs to take out the complementary shape in order to expose the cut-out ( FIG. 6A ). Sheet sections  404  are folded along fold-lines  406  in the direction of arrows  408  ( FIG. 6B ), and then along fold-lines  410  in the direction of arrows  412 . This results in the mirror-image longitudinal units  104   a  and  104   b.  The mirror-image units are then folded along fold lines  414  in the direction of arrows  416  ( FIG. 6C ), to bring faces  418  and  420  into close proximity, thereby forming the planar internal member  108  ( FIG. 6D ). It is of note that the cut-outs  402  are positioned such that, once folded into the final support element shape, the cut-outs are aligned to define opening  114 . 
         [0078]    Once all elements are formed, the crossbar  102  is fitted into the openings  114  and  116 , and the distance between support elements  104  and  106  can be adjusted as required, as seen in  FIG. 7 .