Abstract:
A method of forming a composite panel with a facade comprising a planar arrangement of thin discrete facers on a body of structural backing material. The method comprises the steps of providing a horizontal casting bed, providing a plurality of facers each with a chamfer at a corner between side and rear walls. Arranging the plurality of facers in abutting relationship atop the casting bed and in a selected pattern in a face down planar configuration so that the chamfers on the facers open upwardly and define narrow elongated sealant channels at joints between contiguous facers. Depositing a sealant in the channels and pouring concrete as a structural backing material atop the facers, the rear surfaces of the facers and the concrete adhering to form a composite panel.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention is directed to a method of forming a composite panel with a facade comprising a planar arrangement of thin discrete facers on a body of a structural backing material.  
         BACKGROUND OF THE INVENTION  
         [0002]    Composite concrete and other panels have been in use for a number of years but have not been entirely satisfactory. A bare concrete panel, for example, may be found lacking aesthetically or in other characteristics such as resistance to certain chemicals, durability, high heat gain from the sun, dirt or grime resistance, etc. Accordingly, a number of methods have been proposed to provide finishes for the front surfaces of panels in order to improve their aesthetic and architectural appearance or other properties.  
           [0003]    For example, a number of different methods have been tried to cast in place or otherwise adhere discrete facing units or “facers” on the front surfaces of panels in finished concrete structures. As is well known, different methods have been employed in holding individual facers in a desired pattern, usually in a common horizontal plane, while concrete is cast over and about them so as to at least partially embed them in a wall or other panel. Facers such as thin concrete units manufactured on masonry block machines may be employed in accordance with the present invention together with bricks, tiles, natural stone, concrete pavers, etc. to provide a visually pleasing appearance or to meet functional or other requirements.  
           [0004]    In manufacturing composite walls, it has been a conventional practice to provide various types of forms, grids etc. in securing the facers in position prior to placing concrete or other structural material thereover. However, such methods have not been wholly satisfactory. For example, leakage of concrete between facers may result in concrete adhering to the faces of the latter and in substantial added expense in subsequent removal thereof. Such prior methods have failed to achieve economic advantage due to complicated and tedious manual steps involved in assembling and removing forms, grids, etc. Obviously, grouting between facers is also required in some designs when the panel is complete.  
           [0005]    It is a general object of the present invention to provide a simplified method for making high quality composite walls and other panels at economic advantage and which yet results in a clean aesthetically pleasing final appearance or improved functional surface of the facer surfaced wall or other panel.  
           [0006]    A further object of the invention resides in a method of making a composite panel which obviates the need for grouting between facers on the panel.  
           [0007]    A still further object is to provide a simplified method which requires minimum manpower and yet provides a panel pleasing in appearance or improved functional surface and which exhibits a high degree of structural integrity.  
         SUMMARY OF INVENTION  
         [0008]    In fulfillment of the foregoing objects and in accordance with the present invention, a method of forming a composite wall or other panel with a planar arrangement of thin discrete facers on a structural backing material comprises the steps of providing a flat preferably horizontal casting bed which may be of either a rigid or deformable material. The ability of the casting bed to deform allows the arrangement of facers accurately in a common plane despite irregularities which may occur on the front faces thereof. Plastic foam or other similar materials may be employed in forming such a casting bed but a fine particulate material in the form of sand is presently preferred with a horizontal casting bed. When facers with smooth flat faces lacking significant irregularities are employed, a rigid or hard surface casting bed may of course be employed preferably with heavy paper, plastic sheet or thin plastic foam thereover.  
           [0009]    A plurality of facers each with a chamfer, bevel, or other recess along at least a major portion of the corner between its&#39; side walls, end walls and rear wall are provided and arranged with the facers in tight abutting relationship and face down on the casting bed. Various geometric patterns may be employed but the facers are in all cases positioned in a face down attitude and in a common plane, so that the aforesaid chamfers or other recesses open rearwardly or upwardly to define narrow elongated channels at the joints between all contiguous facers. Certain of the channels with two adjacent opposing chamfers may take “V” configurations in cross-section while others with only one chamfer may take one half (½) “V” configurations in cross-section.  
           [0010]    The chamfers or other recess forming configurations provide narrow elongated arcuate, angular or vertical surfaces which are engaged by concrete or other backing material to form a seal which prevents water from thereafter seeping behind the facers. In the absence of such a seal, subsequent freezing and thawing may loosen and even cause facers to break away from the structural backing material.  
           [0011]    In addition to the foregoing, sealant may be placed in the elongated recesses or channels and may also take a variety of forms. For example, elongated unitary sealing members, hardenable liquids, or fine particulate materials such as sand may be used, the latter being presently preferred. A castable structural backing material such as concrete or other cementitious material is then placed or poured rearwardly of the facers and both conforms to and adheres to the rear surfaces thereof as it cures and hardens. A composite wall or other panel is thus formed and may then be moved to its operative position. For example, if the panel takes the form of a tilt-up wall formed horizontally, an upward swinging movement through 90° may be effected from its horizontal casting bed.  
           [0012]    Generally, the facers have a rectangular configuration and the rear corners thereof are beveled or chamfered at corners between each end wall and their rear walls and at least one side wall and rear wall corner. Chamfers or other recesses may take various configurations viewed in cross-section including rectangular and arcuate, but a flat angularly inclined surface extending between adjacent right angularly related side or end and rear facer surfaces is preferred. When a sealant such as sand is employed, a subsidiary method step may take the form of depositing sand on the rear surfaces of the facers and sweeping the same into the sealant channels with the remainder of the facer rear surfaces being cleaned for good adhesion of the concrete.  
           [0013]    Preferably, the rear surfaces of the facers are also provided with integral rearwardly and upwardly projecting structural connecting means which are enveloped during the pouring of concrete and thereafter firmly embedded in the cured concrete for enhanced structural integrity of the wall or other panel. Such walls or other panels are found to be substantially stronger than walls or panels without facers and may even approach the strength of monolithic concrete walls or panels of equal overall thickness. The connecting means presently take the form of a series of spaced apart parallel ribs integral with the bodies of the facers. Further, the ribs are preferably formed as shown with dove-tail configurations in cross-section defining complementary generally dove-tail grooves therebetween.  
           [0014]    Still further in accordance with the preferred form of the invention, a plurality of spring clips are provided to interconnect the aforementioned ribs. Some of the clips may be installed in interconnecting relationship on aligned ribs of contiguous facers arranged in end-to-end relationship and others on contiguous half ribs arranged in side-by-side relationship on adjacent facers in like relationship. The clips are preferably of generally dove-tail configuration viewed in cross-section with short opposing side legs defining entry openings for the dove-tailed ribs. Further, the legs of each clip are inwardly inclined toward the mouth of the clip opening so that the clips may be snapped into firm embracing engagement on the ribs in relative movement toward the ribs. Thereafter the clips serve to urge facers and especially the side-by-side facers firmly together in abutting engagement to prevent concrete leakage downwardly there-between.  
           [0015]    Further, the clips also maintain the facers in a common plane preventing accidental or unintended displacement of individual facers. Still further, the clips aid in urging facers having uneven front surfaces and facers improperly positioned toward a common plane.  
           [0016]    A tool of appropriate design may also be provided for ease of convenience in the assembly of the clips on the ribs.  
           [0017]    Finally, a plurality of upstanding anchors may be provided with base portions mounted on the ribs of the facers and supports for horizontal reinforcing members such as “re-bars” may also be provided with the latter also mounted on rear surfaces of the facers in engagement with ribs and inter-rib grooves. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]    [0018]FIG. 1 is a side view of a “facer” constructed in accordance with the present invention.  
         [0019]    [0019]FIG. 2 is a front view of the facer of FIG. 1.  
         [0020]    [0020]FIG. 3 is a view taken from the end of the facer.  
         [0021]    [0021]FIG. 4 is a perspective view of the rear surface of the facer.  
         [0022]    [0022]FIG. 5 is a side view of a partially constructed wall with facers disposed atop a casting bed of sand in abutting relationship and with one-half (½) “Y” sealant channels between facers.  
         [0023]    [0023]FIG. 6 is a fragmentary enlarged view of a facer joint taken from FIG. 5.  
         [0024]    [0024]FIG. 7 is a view similar to FIG. 5 but with sand disposed in the sealant channels.  
         [0025]    [0025]FIG. 8 is a fragmentary enlarged view of an inter-facer joint as in FIG. 6 but with sand deposited in the sealing channel.  
         [0026]    [0026]FIG. 9 is a side view similar to FIG. 5 and  7  but with concrete deposited atop the facers.  
         [0027]    [0027]FIG. 10 is a fragmentary enlarged view of a facer joint as illustrated in FIG. 9.  
         [0028]    [0028]FIG. 11 is enlarged fragmentary view of a facer joint as in FIG. 6 but with an Y-shaped sealant channel.  
         [0029]    [0029]FIG. 12 is similar to FIG. 11 but with sand deposited in the channel as a sealant.  
         [0030]    [0030]FIG. 13 is a view similar to FIG. 11 and  12  but with structural material deposited atop the facers.  
         [0031]    [0031]FIG. 14 is a perspective view of a plurality of facers positioned in face down abutting relationship and partially forming the front section of a panel, spring clips being mounted on ribs which project upwardly from the facers.  
         [0032]    [0032]FIG. 15 is an enlarged perspective view showing an individual spring clip.  
         [0033]    [0033]FIG. 16 is a top view of an alternative clip.  
         [0034]    [0034]FIG. 17 is a perspective view of the spring clip of FIG. 16.  
         [0035]    [0035]FIG. 18 is a side view of the spring clip of FIG. 16, 17.  
         [0036]    [0036]FIG. 19 is a side view of an anchor adapted to be mounted on a back surface of a facer.  
         [0037]    [0037]FIG. 20 is an opposite side view of the anchor of FIG. 19.  
         [0038]    [0038]FIG. 21 is a perspective view of the anchor of FIGS. 19 and 20.  
         [0039]    [0039]FIG. 22 is a top view of the anchor.  
         [0040]    [0040]FIG. 23 is a top view of a “chair” for supporting elongated concrete reinforcing members or “re-bars”.  
         [0041]    [0041]FIG. 24 is a perspective view of the re-bar chair of FIG. 23.  
         [0042]    [0042]FIG. 25 is a side view of the chair.  
         [0043]    [0043]FIG. 26 is another side view better showing an upwardly open groove for receiving and supporting a re-bar.  
         [0044]    [0044]FIG. 27 is a perspective view showing a number of facers with chairs mounted thereon as in FIGS.  23 - 26 , the chairs being shown with their legs spring mounted in the dove-tail grooves of the facers.  
         [0045]    [0045]FIG. 28 is a side view showing the chair supporting right angularly arranged re-bars.  
         [0046]    [0046]FIG. 29 is an enlarged perspective view showing a chair mounting a pair of right angularly arranged re-bars.  
         [0047]    [0047]FIG. 30 is a top view of a chair having three mounting grooves arranged in alignment with three opposite grooves; thus, three re-bars being accommodated in right angular arrangement with three additional re-bars.  
         [0048]    [0048]FIG. 31 is a perspective view of the re-bar chair of FIG. 30.  
         [0049]    [0049]FIG. 32 is a first side view of the re-bar chair of FIGS. 30 and 31.  
         [0050]    [0050]FIG. 33 is a second and opposite side view of the chair.  
         [0051]    [0051]FIG. 34 is a perspective view of the chair of FIGS.  30 - 33  with a single re-bar mounted thereon in each right angular direction and with the base portion of the chair mounted in embracing relationship on ribs on the back of a facer.  
         [0052]    [0052]FIG. 35 is a perspective view similar to FIG. 34 but with a base portion of the chair entered in and engaging the opposite side-walls of an inter-rib groove.  
         [0053]    [0053]FIG. 36 is a perspective view showing a number of facers with a large chair having three aligned grooves in one direction and five aligned grooves in right angular arrangement therewith.  
         [0054]    [0054]FIG. 37 is a side view of a tool for installing spring clips with an associated clip shown in an expanded condition.  
         [0055]    [0055]FIG. 38 is a similar view of the same tool with the clip in a contracted position.  
         [0056]    [0056]FIG. 39 is a perspective view illustrating operation of the tool in respect to a spring clip.  
         [0057]    [0057]FIG. 40 is a top view of the tool of FIGS.  37 - 39 ; and  
         [0058]    [0058]FIG. 41 is a perspective view of an insulated panel constructed in accordance with the method of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0059]    Referring now particulary to FIGS.  1 - 4 , a facing unit or “facer” is illustrated generally therein at  10  in a presently preferred form. As mentioned above, facers may take a wide variety of forms including thin concrete units capable of formation in a masonry block machine, conventional bricks, concrete pavers, natural stone, etc. The facer  10  shown is of the concrete type formed in a masonry block machine and has a decorative face of pleasing appearance as best illustrated in FIG. 2. The facer also has beveled or chamfered corners  12 ,  12  between the end walls and rear wall and along one side wall and rear wall corner. The opposite rear wall and side wall corner is devoid of a bevel or chamfer as best illustrated in FIGS.  3 , and  4 , this due to the inability of a block machine to conveniently form chamfers on all four rear corners of a facer.  
         [0060]    Connecting means for co-operation with concrete or other structural backing on the rear surface of the facer preferably take the form of integral dove-tail ribs as shown. A single centrally located full rib  14  is shown in FIG. 1 and partial, substantially half ribs  16 ,  16 , are also shown in FIG. 1. at the sides of the facer. Dove-tail grooves  18 ,  18  are defined between ribs as best illustrated in FIGS. 1 and 4.  
         [0061]    Referring now to FIGS.  5 - 10 , the method of the invention is illustrated sequentially. In FIG. 5 a plurality of facers  10 ,  10  are shown positioned in abutting face down relationship and in a common plane atop casting bed  20 . The casting bed  20  may be rigid or deformable as mentioned. Foam plastic and other materials may be employed in a deformable bed but fine particulate material, such as sand, is preferred and is shown in FIGS.  5 - 10 . Form members  22 ,  22  establish the peripheral limits of the casting bed. Channels defined between facers are at least one-half (½) “Y” configurations viewed in cross-section and may accommodate sealant as mentioned. As best illustrated in FIG. 6 a chamfer  12  on a right hand facer forms a one-half (½) “Y” channel with the straight face of a left hand facer adjacent thereto.  
         [0062]    In FIGS. 7 and 8, a sealant has been introduced to the channels  24  and may comprise a fine particulate material, preferably sand as mentioned above. This may be conveniently accomplished by depositing sand atop the backs of the facers, sweeping the same into the sealant channels  24 ,  24  and concurrently sweeping the sand away to clean the backs of the facers for good adherence to the concrete.  
         [0063]    [0063]FIGS. 9 and 10 illustrate the facers  10 ,  10  with a cementitious structural member cast thereabove, conforming to and adhering thereto. Concrete is preferably employed as mentioned but various other materials capable of being cast in situ may also be used. As best illustrated in FIG. 10, the concrete is formed about the ribs  14 ,  16  and at the joints therebetween. The concrete also engages and forms a seal with the walls of the chamfers and with an elongated narrow vertical surface  25  between the chamfers and the bottoms of the grooves. This prevents water seepage behind the facers which might otherwise result in loosening and “fall off” of the same over time. Downward penetration of the concrete between facers during pouring and curing is prevented by the sand  26  which forms a seal between the facers as stated.  
         [0064]    In FIGS.  11 - 13 , joints  24   a ,  24   a  are shown between facers  10 ,  10 . The “Y” shaped sealant channels result where adjacent facers are provided with identical opposing chamfers  12 ,  12 . The method employed is of course identical with regard to FIGS.  5 - 10 . That is, sand is introduced to the channels as shown at  26 . The excess sand may be swept clean and the concrete or other cementitious material  28  then poured and allowed to cure and harden as shown in FIG. 13, the sand  26  serving its sealing function in each of the channels as stated.  
         [0065]    In FIG. 14, a plurality of facers  10  are shown in a partially complete panel in association with optional spring clips  30 ,  30 . The spring clips  30 ,  30  each have a dove-tail configuration complementary to the cross-section of the ribs  14 ,  16 . That is, a single central rib  14  can be interconnected with a second rib  14  in end-to-end relationship as shown. Further, end ribs  16 ,  16  in side-by-side relationship can also be readily interconnected by a clip  30  as shown. Clips  30 ,  30  may be entered about a single rib  14  or a pair of adjacent end ribs  16 ,  16  in relative endwise movement and positioned as desired to serve their interconnecting function. Preferably, however, the clips  30 ,  30  are urged downwardly over the ribs in a snap action with opposite legs  32 ,  32  first being spread apart and then contracting to firmly embrace the ribs.  
         [0066]    FIGS.  16 - 18  illustrate a second form of the clips at  30   a  and it will be observed that each of the clip configurations includes openings as at  34  and  34   a . The openings  34  and  34   a  allow concrete to penetrate and adhere to the ribs during pouring and subsequent curing.  
         [0067]    The installation of the clips may be accomplished manually or with the aid of a tool  36  illustrated in FIGS.  37 - 40 . The tool  36  has manually operable handles  38 ,  38  pivotally connected at  40  and opposing operating arms  42 ,  42  each with a small lip  44 . The lips  44 , 44  extends outwardly and engage small hooklike members  46 ,  46  at the ends of the legs of a clip  30 . The hooklike members face inwardly and the lips  44 ,  44  on the tool engage the hooks and spread the legs  32 ,  32  of the clips for easy movement of the same about a rib. Once a clip has been positioned about the rib the tool may be released to allow the legs to spring inwardly and snap into firm embracing relationship with one or more ribs. FIG. 38 shows the release of the clip and the operative movement of the tool is illustrated in FIG. 39. Once the clips have been installed as shown in FIG. 14, pouring of the concrete may be initiated as described above.  
         [0068]    The clips  30 ,  30   a  may be employed to ensure firm abutting engagement of the facers in the embodiment described above with a sealant disposed in the recesses or channels at facer joints. Further, that satisfactory results may be achieved with the clips in some cases even without sealant disposed in the channels between facers. That is, the forces provided by the clips bringing the facers into firm engagement may result in facer joints which are sufficiently tight to prevent penetration of the concrete through the joints and the resulting undesirable flow of small quantities of concrete onto the front surfaces of the facers. These conditions may prevail when facers with particularly smooth surfaces are employed. Further, it may be possible to eliminate both the sealant and the clips in certain situations. Here again, abutting facers with exceptionally smooth side surfaces may result in joints sufficiently tight to prevent concrete penetration.  
         [0069]    A product known as Self Compacting Concrete not requiring vibration may be employed to advantage particularly in this latter method embodiment as a structural backing material. In the absence of vibration, as required with conventional concrete for uniformity and the filling of small voids such as the sealant channels, there is considerable less likelihood of penetration or leakage through the facer joints.  
         [0070]    In addition to the foregoing, “anti bonding agents” and “retarders” may be applied to the front surfaces of the facers. This facilitates or may completely eliminate cleaning of the facers as a final step in the process of making the walls or other panels of the present invention.  
         [0071]    In certain applications, additional structural integrity and strength may be required in connecting the facers to the structural backing material of the panel. FIGS.  19 - 22  illustrate an anchor employed for such purposes. In FIG. 36 the anchor is shown in operative position on a facer prior to the casting of concrete thereabout. The anchor has a base portion  48  adapted to enter and be retained in a groove  18  as illustrated in FIG. 36. Upstanding portion  50  is adapted to be embedded in the concrete and, thereby provide structural strength firmly interconnecting the facers and the structural backing. As shown, the base portion takes a generally Z shape with opposing legs  52 ,  52  adapted to enter a groove  18  and engage the opposing ribs defining the groove. The upper portion  50  of the anchor includes an integral arm which extends horizontally with the anchor mounted on the facers and which is also embedded in the concrete as mentioned. “A chair” for supporting elongated reinforcing members, commonly known as “re-bars”, is illustrated in FIGS.  23 - 29  at  54 . The chair  54  has four (4) legs and defines a pair of right angularly arranged upwardly open grooves  56 ,  56  at an upper portion thereof. Legs  58 ,  58  enter the grooves  18 ,  18  as best illustrated in FIGS. 27 and 29 and may be of flexible construction so as to snap into position. The reinforcing members or “re-bars” may then be mounted in the grooves  56 ,  56  prior to pouring the concrete so that the re-bars are thereafter embedded in the concrete.  
         [0072]    FIGS.  30 - 35  illustrate a re-bar chair for supporting six ( 6 ) re-bars in a three (3) each right angular arrangement and FIG. 6 a five (5) and three (3) right angular arrangement.  
         [0073]    In FIG. 41 an insulated panel is illustrated in cross-section and comprises a plurality of facers  106 ,  106  in planar arrangement as described above. A relatively thin layer of concrete  50  is then cast over the facers with a conventional insulating panel  52  disposed thereabove. Finally, a heavier layer of concrete  54  is cast atop the insulating panel with transverse connectors  56 ,  56  embedded in the concrete and preferably extending from the thin layer of concrete  50  through the insulating panel  52  and into the heavier layer of concrete  54 .  
         [0074]    As will be apparent from the foregoing, a method has been provided for forming a composite panel of groutless construction in an extremely simple and yet highly efficient manner. The method may obviously be employed at economic advantage in the construction of composite tilt-up walls, precast and other panels having a wide variety of facial characteristics with a minimum of manual labor and an aesthetically pleasing and/or functionally improved end result.