US 3478480 A
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Description (OCR text may contain errors)
w. E. SWE NSON THIN STONE SUPPORTING AND ANCHORING SYSTEM Nov. 18, 1969 2 Sheets-Sheet 1 Filed June 17, 1968 n llllllllll ll+r l l l I I l l I l I l .IIL,
ITIOZ/VfXS Nov. 18, 1969 w. E. SWENSON 3,478,480
THIN STONE SUPPORTING AND ANCHORING SYSTEM Filed June 17, 1968 2 Sheets-Sheet 2 I .v I l I I I i I I I l H g j TL F :v j I I 1 :1" i "19 m I I I I I l l I 550 I I awavroxz, MLLMM E. .S'WEMS'OA/ ITTOZVEKS' United States Patent THIN STONE SUPPORTING AND ANCHORING SYSTEM William E. Swenson, 6807 Capstan Drive, Annandale, Va. 22003 Filed June 17, '1968, Ser. No. 737,515
Int. Cl. E04b 2/30, 2/02; E04c 2/04 US. Cl. 52-396 11 Claims ABSTRACT OF THE DISCLOSURE A system for supporting and anchoring contiguous slabs of material for forming a building facing is provided wherein vertical bars carry angle brackets, each having a horizontal leg to provide repeating cantilever supporting points for said slabs. The upper and lower operative edges of said slabs are provided with semicircular kerfs which cooperate with an anchoring disc on the brackets. A strip of resilient material is positioned between the stone slab and the supporting leg of the angle bracket whereby the slab is isolated from expansion and contraction as well as vibration stresses. Clearance space within the semicircular kerfs of the lower edge of the stone is filled with mortar for stability and resilient compound is utilized within the clearance space of the kerfs of the upper edge to insure the necessary movement and flexure of the slab.
The present invention relates to building construction, and more particularly, to a supporting and anchoring system for a thin material facing for a building.
In modern day large office or apartment building construction, it has been proposed to construct a building of reinforced concrete and then form the exterior of the building, as well as parts of the interior, such as the lobby, with a facing of contiguous, thin slabs of marble, granite or the like. This type of construction obviously lessens the total expense of the stone facing of a given building in that less stone is needed per square foot of area to be covered without in any way aflecting the architectural beauty of the building. Thin stone facings further reduce the cost of construction because 1) installation is generally faster and requires less labor than the old method of laying stone with mortar; (2) the reinforced structure of the building may be designed to support less dead weight since the total weight of the stone is greatly reduced; and (3) the facing, although permanently installed for the life of the building, is relatively easy to dismantle for reuse without damage to the individual stone slabs when the building is to be razed to make way for even more efiicient use of the land.
Previously, several systems have been proposed by which thin stone slabs may be mounted as a permanent building facing in an attempt to gain the above advantages; an exemplary system being disclosed by the patent to J. S. Zibell 3,234,702, dated Feb. 15, 1966, and entitled Anchoring System for the Installation of Slabs on Vertical and Overhead Surfaces. While such systems have proven to be generally acceptable in providing a building with a stone facing more economically than before, they have been subject to certain shortcomings and disadvantages.
First, in all of the systems of which I am aware it is required that each of the stone slabs be provided with extended kerfs or grooves along the upper and lower operative edges thereof. In some cases, such as in the Zibell system, the grooves must extend along the entire length of the edges of the slab to receive the cantilever supporting and anchoring member. This groove materially weakens the stone along these edges due to the reduction in thickness of the stone so that if there is the slightest weak- 3,478,480 Patented Nov. 18, 1969 ice ness or fault in the stone adjacent said edges, or if the stone is accidentally bumped against the building structure or other fixed object, breakage is likely to occur. The weakening of the stone slabs is particularly pronounced and critical at the corners due to lack of reinforcement along the edge at the end of the groove. As will be realized, if one of these operative edges of a slab is thus broken, the slab must be scrapped thus having an adverse 'atfect on the cost of the installation.
Further, in the Zibell and other prior systems, the supporting and anchoring members have been of a configuration or shape which requires an engagement with the groove in the stone that has proven to be diflicult in practice to match during installation, thus requiring a large amount of tedious and time consuming guiding and coaxing by the installer. Furthermore, in the systems wherein the members are continuous and require engagement along their entire length with the slabs as described above, an imperfection or accidental bending of one of the mating legs of the supporting and anchoring members during handling results in the entire member having to be replaced, thereby frurther adding to the cost of the installation. Lastly, in prior art systems known to me, the stone slabs are supported by direct contact with the metal supporting and anchoring members, thus greatly increasing the chances of the facing being weakened or cracked under the reoccurring forces of differential expansion or contraction caused by temperature changes and the forces of vibration to which buildings are commonly subjected; the latter including not only possible earthquakes and tremors, but also vibrations which have become a problem only in recent years, such as those resulting from adjacent freeway traffic or shock waves of jet aircraft.
Accordingly, it is a primary object of the present invention to provide a sup-porting and anchoring system of the type described which overcomes the foregoing shortcomings and disadvantages.
It is another object of the present invention to provide a supporting and anchoring system and novel brackets for use therewith for installing thin stone facings which require only the formation of spaced, semicircular kerfs in the operative edges of the stones so as not to materially weaken the same.
It is still another object of the present invention to provide an improved supporting and anchoring system which allows easier and more accurate installation including final adjustment and plumbing of the slabs.
It is still another object of the present invention to provide a system for supporting and anchoring thin stone slabs wherein the stones are resiliently supported and are capable of the required movement and flexure so as to prevent deleterious stresses being transmitted to the slabs as a result of expansion and contraction and/or vibrations.
Briefly describing the system of the present invention. a. plurality of vertical fastening bars or struts are attached to the building structure and define multiple columns for receiving thin stone slabs which together form the facing of the building. These bars thus form the foundation of the present system, however the specific construction of the same forms no part of the present invention so that they can be selected from any one of several different fabricated steel members suitable for the required load bearing function; one such bar being manufactu'red under the trade name Versabar by Versabar Corp., Jersey City, NJ. A series of spaced angle brackets, each with an outwardly projecting horizontal leg, are carried by each fastening bar to provide repeating supporting and anchoring points on the building structure. In the preferred embodiment illustrated for purposes of disclosing the invention, a pair of horizontally adjacent brackets are utilized to support and anchor a slab along the lower operative edge thereof; the same pair of brackets serving to anchor the upper operative edge of the adjacent slab below.
In accordance with a salient feature of the present invention, to perform the anchoring function each of the slabs is provided with semicircular kerfs formed in the upper and lower operative edges thereof, which kerfs correspond to opposite semicircular portions of a disc fixed on the supporting leg of the angle brackets. With this innovation, it will be realized that several advantages over the prior art discussed above have been gained.
First, the necessity for an extended groove along the edges of the slab with its attendant weakening effect has been eliminated. The spaced, semicircular kerfs in the stone which are substituted therefor have been found not to materially weaken the edge in which it is formed since solid stone is left at both sides for reinforcement. Further, a kerf having a semicircular configuration as in the pres ent invention, has been found to have the least adverse effect on the strength of a stone that might be imperfect since the inner face of the kerf is curved and therefore any line faults which might exist in the stone adjacent the operative edges are not as likely to correspond with the outline of said kerf. In short, all of these factors resulting from the use of the semicircular kerf of the present invention advantageously reduce the likelihood of breakage of the stone along the operative edges to make for a more efiicient and reliable system.
Also, a savings is realized in the cost of preparing the stone in accordance with the present invention since the semicircular kerfs along one operative edge of the stone may be formed simultaneously by merely bringing the stone into engagement with a pair of properly spaced rotary saws with no lateral movement of the stone along the edge being required. In addition, the semicircular anchoring disc portions of the disc on the bracket correspond to the cooperating kerfs so as to give the maximum interface engagement for the anchoring function. Furthermore, this relationship greatly enhances the ease of installation since the mating curved surfaces of the kerf and the disc may cooperate with each other for a guiding effect as the stabs and the brackets are placed in position with respect to each other during installation.
The lower supporting edges of each of the slabs are provided with clearance cutouts in the areas corresponding to the angle members with a strip of resilient material being positioned in each of the cutouts so that the support for the slabs is resilient. Each individual slab is thus capable of movement and fiexure as required by any differential expansion or contraction between said slab and said building and is effectively insulated from vibrations imparted to the building by the various sources mentioned above.
Means are provided for roughly adjusting both the vertical and horizontal position of each bracket so that each slab may be properly positioned during installation. Preferably, a clearance space is provided between the semicircular kerfs and the discs of the brackets so that each of the slabs may also be finally adjusted in the horizontal plane and plumbed in an advantageous manner after the brackets have been locked in place. Thus, the clearance space is sufiicient on all sides of the circular disc to allow for any anticipated final adjustment of the stone slab by simply applying the necessary force to move the slab as required while visually checking the alignment and plumbed position.
After the final adjusted position has been reached, according to the invention, a compressible mortar is used to fill the clearance space of the kerfs along the lower edge so that the slab is stabilized at the point of support, but at the same time is not rigidly anchored which would destroy the effectiveness of the above described resilient mounting. A mixture of two parts cement o one part ground limestone has been found to be particularly adapted for this purpose of obtaining maximum stability without rigidity. The clearance space between the kerf and the disc in the upper edge of the slab is filled with a resilient material, such as a synthetic rubber base caulking compound, whereby the slabs are also resiliently anchored along their upper edge to further insure the allowance of the necessary movement and flexure of the individual slabs.
Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description, wherein I have shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by me of carrying out my invention. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modification in various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.
In the drawings:
FIGURE 1 is a perspective view of one environment in which the anchoring and supporting system of the present invention may be utilized, namely a typical mullion;
FIGURE 2 is a front view of another type of installation, namely a planar wall;
FIGURE 3 is a top view of one-half of the mullion of FIGURE 1 showing details of the system of the present invention in a mullion installation;
FIGURE 4 is a side view of the system of the present invention as shown in either FIGURE 1 or 2, with details of a suitable installation adjacent the ground floor and the roof being included;
FIGURE 5 is an enlarged perspective view of a supporting and anchoring bracket constructed in accordance with the principles of the present invention;
FIGURE 6 is an enlarged cross-secti0nalview taken along line 6-6 of FIGURE 3 showing the manner in which the bracket of FIGURE 5 engages the adjacent stone slabs;
FIGURE 7 is a cross-sectional view taken along line- 77 of FIGURE 6 also showing the relationship between the bracket of the invention and the stone slabs; and
FIGURE 8 is a partial edge view of a stone slab prepared in accordance with the present invention.
Proceeding with a more detailed description of the present invention, reference is now made to FIGURE 1 wherein is shown a typical installation in the form of a mullion 10 in which the supporting and anchoring system of the present invention may be utilized. As is conventional, the mullion 10 is positioned between windows 11, 12 and includes a plurality of contiguous slabs S. To form the mullion 10, the slabs S are arranged in multiple vertical columns disposed at an angle to each other. The slabs S may be generally described and are referred to herein as being thin, this term being known in the art as describing facing slabs in the neighborhood of one inch in thickness. Usually the slabs S are of marble, granite, or any other suitable stone for forming a building facing; however, it should be understood that while the system is particularly well adapted for stone installations and has certain important advantages in this field, other building materials in slab form, such as metal or wood, could be erected by using the inventive concepts of the present system if desired. As illustrated, the slabs S may be rectangular, or in the alternative, may be any other shape consistent with good bullding design.
Another typical installation in which the supporting and anchoring system of the present invention could be used is illustrated in FIGURE 2, and comprises a planar wall 13 also constructed of multiple columns of the stone slabs S. Accordingly, it should be realized by those skilled in the art that the present system is adapted to any situation wherein a thin stone facing is to be applied to a building structure.
For ease of description and since the details of the system of the invention are the same in any selected installation, only the supporting and anchoring system of the present invention as applied to the mullion will be specifically described hereinafter. Thus, as can be seen in FIG- URES l and 3, the mullion 10 comprises a plurality of vertically extending fastening bars or struts to which are attached angle brackets 16, which, in turn, support and anchor the slabs S in a manner to be discussed in detail later. The bars 15 and brackets 16 are preferably used in pairs for the typical size stone used for facing which may, for example, be approximately one and one-half feet wide and five feet long and weigh approximately 100 pounds. However, it is to be understood that any desired number of the supporting and anchoring brackets 16 could be utilized in accordance with the broad concepts of the present invention. For example, if the slab S being installed is narrow and light in weight, it is contemplated that only one vertically extending bar 15 and bracket 16 combination might be used per column of facing; whereas, on the other hand, three or more are contemplated as possibly being utilized to advantage for oversized slabs.
As illustrated and mentioned above, the bars 15 may be of the Versabar type and are attached in a typical fashion to each of the horizontal floors of a building structure, such as the floor F shown in FIGURE 3. One suitable arrangement for this purpose includes a support angle 17 attached to the thickness of the floor F by means of a mounting track 18 encased therein. Also as shown in FIGURE 3, the windows 11, 12 may typically have a window frame 20 which is maintained in the proper spaced relationship to the adjacent stone slab S by means of any number of spacer clips 21. It should be emphasized that these features covering the actual attachment and positioning of the bars 15 on the building structure are not critical and have been illustrated merely to show the environment of one use of the system of the present invention.
Referring now briefly to FIGURE 4, a cross-sectional view of a column of the stone slabs S is shown and the general manner in which the brackets 16 support and anchor said slabs S can be seen. Note, in particular, that each bracket 16 supports and anchors the slab above by operative engagement with the lower edge thereof, designated by the reference numeral 22, and also anchors the adjacent slab below along upper edge 23. Thus, to form the column, the bar 15 extends the full height of the building between ground floor G and roof R with the brackets 16 defining vertically spaced supporting and anchoring points between the slabs S. At the bottom and top of the column, specially adapted brackets 16' are utilized to engage the single adjacent slabs, which brackets 16' will be described in detail and more clearly understood after consideration of the novel construction of the brackets 16 that follows.
As illustrated in FIGURES 5 and 6, the bracket 16 comprises an angle member 24 including a horizontal leg 25, which forms the cantilever type support for the stone slab S, and a vertical leg 26 which through an elongated aperture 26a is attached to the bar 15. Fixed to the outer limit edge of the leg is a disc 27 forming upper and lower semicircular portions 28, 29, respectively, which, as will presently be explained, cooperate in anchoring relationship with the respective edges 22, 23 in adjacent ones of the slabs S.
The angle member 24 is preferably selected from a conventional stock size angle in accordance with the particular weight of stone being installed; the desired length of the bracket 16 being gained by merely cutting the stock angle into the selected length. If desired or necessary, the angle member 24 can be custom fabricated by merely bending a fiat plate into the form of an angle and then cutting the same into the selected lengths as before. The
disc 27 is preferably selected from the same material as the angle member 24 and attached to the leg 25 by welding across the center (note FIGURE 6). For rust resistance, all of the parts of the supporting and anchoring system, including this bracket 16, are galvanized after fabrication, or if desired, all of the parts may be fabricated of suitable rust resistant metal, such as stainless steel.
The critical interrelationship between the bracket 16 and the edges 22, 23 of the slabs S is best shown in FIG- URES 6-8. First, semicircular kerfs 35, 35a are formed in the upper and lower edges 22, 23 of the slab S, respectively; the positioning being preferably halfway between the opposite faces of the stone (see FIGURE 8). Of importance is the fact that the kerfs 35, 35a have a semicircular configuration which has been found to provide the least amount of weakening of the edges of the stone whereby chipping of the stone during handling and installation is greatly reduced. This is so since, as can be seen in FIGURE 8, the areas adjacent the ends of the kerfs 35, 35a are solid for reinforcement of the stone in the load bearing areas adjacent the bracket 16. Furthermore, since the inner faces of the kerfs 35, 35a are curved from end to end, there are no unnecessary sharp edges that might form a weakened point where a crack in the stone is likely to be formed. Still further, any preexisting straight line faults in the stone would not be followed by and thus made critical by the formation of the kerfs 35, 35a because of the curved configuration. Finally, as will be realized from viewing FIGURE 8, the kerfs 35, 35a extend over only a short distance of the operative edges 22, 23 so that the major part of said edges 22, 23 is not weakened in any manner, and particularly by being spaced from the corners of the stone, which have in the past been highly susceptible to being chipped, a major disadvantage of the prior art has been alleviated.
As best shown in FIGURES 6 and 7, there is provided a clearance space between the kerfs 35, 35a and the corresponding portions 28, 29 of the disc 27. The main reason for this is to allow the relative position between the stone slab S and the bracket 16 to be finally positioned and plumbed after the initial position of the bracket 16 has been located. Thus, space for final adjusting movement of the slab S toward and away from the building is provided by clearance on opposite sides of the disc 27, which adjusting movement is indicated by the double arrows 37, 38 in FIGURE 6. Similarly, clearance is provided between the sides of the kerfs 35, 35a and thedisc 27, as is best shown in FIGURE 7, for sideways final adjusting movement of the slab S as indicated by the arrows 39, 40.
The kerfs 35, 3511 are selected to have centers 41, 41a which are spaced outwardly away from the respective edges 22, 23 for a specific reason. In particular, this offset positioning of the centers 41, 41a means that the kerfs 35, 35a are more closely spaced to the disc 27 at the top than at the sides, as is clearly shown in FIGURE 7. While any desired ratio could be used, the desired results have been found to be obtainable with a design for two times more space at each side than at the top; i.e., one-half inch at each side as opposed to one-quarter of an inch at the top. This allows sufficient sidewise adjusting movement in the direction of the arrows 39, 40 while retaining the depth of the cut into the edges 22, 23 of the stone at a minimum. An advantage in forming the kerfs 35, 35a also flows from this arrangement in that the kerfs 35, 35a can be formed by merely moving the slab S relative to a rotating saw blade having a radius equal to that defined by the radial distance between the kerfs 35, 35a and their respective centers 41, 41a until the desired depth of cut is reached. Theshaft of the rotary saw used is thus spaced from the edges 22, 23 so that there is no interference with the stone. Also, of course, since the kerfs 35, 35a do not extend along the length of the edges 22,
23, no lateral movement of the stone relative to the saw is necessary, thus making the stone preparation more economical.
The lower edge 22 of the stone slab S is, in addition, formed with a shallow cutout 45 extending along the rear of said slab S, as shown in FIGURE 8. This cutout 45 is selected to be slightly longer than the width of the bracket 16 so that, as shown in FIGURE 7, a resilient strip 46 may be positioned between the horizontal leg 25 and the slab S to form a resilient interface therebetween. It will be realized that since the disc 27 is mounted at the outer limit of the leg 25, the entire load bearing function is performed through the resilient strip 46 so that the slab S is isolated from vibration of the building. Furthermore, any differential lateral expansion or contraction of the slab S wth respect to the building, i.e., in the direction of the arrows 39 (see FIGURE 7), is absorbed by this resilient connection thereby obviating any danger of damage to the slab S.
The strip 46 of resilient material is preferably a synthetic rubber, such as butyl rubber, which is highly resistant to abrasive wear and moisture; however, it is to be realized that any type of rubber, plastic or the like material consistent with the objectives of the present invention could be used. The strip 46 is preferably positioned in the cutout by attachment with a suitable adhesive, such as an epoxy resin, prior to installation so that proper alignment within said cutout 45 and opposite the leg 25 is certain.
The clearance space within the kerf 35 in the lower edge 22 may be filled with a mortar to gain an additional advantage of stabilization of the slab S adjacent the load bearing area of the stone. The mortar 50 must be compressible and not rigid to allow the necessary movement in the direction of the arrow 39 upon the above described expansion and contraction. A suitable mortar mixture that has been discovered as being useful in this respect comprises two parts cement to one part ground limestone, which mixture gives maximum stability but allows the desired slight compressing action as needed. It should be noted that due to the increased clearance spaces at the ends of the kerf 35 sufiicient mortar thickness is assured for this necessary movement. Further, since the edge face of the disc 27 is relatively thin, such compression of the mortar 50 is allowed without difiiculty; whereas, excellent stability of the slab S toward and away from the building (arrows 37, 38, FIGURE 6) is gained through the large interface area with the mortar 56 (defined by the extent of the faces of the disc 27) and through a restricted space for the mortar 50 of only approximately one-eighth of an inch in these locations.
The clearance space within the kerf 35a of the upper edge 23 may in a similar manner be filled with a suitable material to secure the final position of the stone. In this instance, it is presently contemplated that a resilient compound best suits the purposes of the invention for anchoring the stone along said upper edge 23 so that this nonload bearing portion of the slab S is capable of freer movement, as is desired. One operative embodiment contemplated by the present invention is to fill this clearance space with a synthetic rubber compound 51 which when in position sets up to retain the stone in the selected plumbed position but which allows the desired freedom of movement and flexure of the stone. Many suitable materials, such as commercial grade butyl rubber compound, can be utilized for this purpose.
As previously mentioned, the angle brackets 16' for the bottom and top stone S in a column, as shown in FIGURE 4, are modified versions of the bracket 16 previously described herein. That is, in the bracket 16 the lower semicircular portion 29 of the disc 27 has been cut off, preferably a slight distance below the center of said disc 27, as denoted by dashed line 53 in FIGURE 5. As shown in FIGURE 4, the angle bracket 16' engages and supports the lowermost stone slab S exactly as before, with the 8 kerf 35 mating with the upper portion 28 of the disc 27 and the clearance space being filled with the mortar 50 to stabilize said slab S. The uppermost modified bracket 16' is inverted from the position shown in FIGURE 5 so that the upper portion 28 engages the kerf 35a in the slab S. Again, as before, the clearance space within this kerf 35a is filled with the rubber compound 51 so that the upper edge of the stone is resiliently located. It should be realized that with this arrangement, all of the kerfs 35, 35a of the slabs S in any one column of the mullion 10 are formed exactly alike and are in the same relative position with respect to the corners to gain maximum economy during cutting of the stones and to avoid the possibility of misplacement in the column during installation.
To seal the interior of the building from outside Weather, suitable rubber sealing rods 55 are positioned in all of the horizontal joints between the adjacent slabs S (note FIGURE 4 and 6). As shown, the disc 27 on each of the brackets 16 acts as a backup stop to the insertion of the rods 55 so that the depth of insertion is constant. As shown in FIGURE 4, the brackets 16' are also operative for this purpose in that the retained length of the lower portion 29 above the line 53 serves as the backup for the sealing rod 55 along the horizontal joints between the mullion 10 and the ground floor G and the roof R. On the outside of the rods 55, a layer of conventional caulking 56 can now be applied with the sealing rods 55 serving as a backup to insure uniformity of depth along all of the horizontal seals to enhance not only the weather-tightness of the mullion 10 but also to insure an attractive exterior. Similar vertical joints 57 between the adjacent slabs S, and the window frame 20 and the adjacent slab S, may be formed.
Having thus described the mechanical structure of the apparatus of the present invention, step-'by-step analysis of the installation of thhe stone slab S into the form of a mullion 10 can be made. The first step is to install the bars 15 along the entire length of the building by attachment to the individual floors F as described above, as well as by securement to conventional end sleeves 60, 61 attached to the ground floor G and the roof R, respectively. Starting at the ground floor G, the necessary bracket or brackets 16' are attached to the bar 15. This may be done in any suitable manner such as through the use of a bolt 62 (see FIGURE 6) which passes through the aperture 26a and is fastened on the interior of the bar 15 by a special nut 63, which is adapted for vertical sliding movement along said bar 15. As the bolt is drawn into position, suitable slotted shims 64 are placed between the front face of the bar 15 and the rear of the bracket 16. These shims 64 determine the rough adjustment of the spacing of the slab S from the building. The lateral position of the bracket 16' is next determined by movement of the same with respect to the bolt 62 along the slotted aperture 26a. Once this has been accomplished, the bolt 62 is drawn down tight in a locked position whereby the rough adjusted position of the bracket 16' has been located.
The next bracket 16 above is attached with the necessary bolt 62, nut 63 and shims 64, and lightly tightened above in readiness for use at the upper edges of the slab ,S. The lower edge 22 of the slab S is then moved into position toward the building and into rough mating engagement of the kerfs 35 with the upper portion 28 of the disc 27 on the bracket 16'. If the slab S is not brought down exactly centered on the disc 27, that is, if the centered position of the disc 27 and the kerf 35 as shown in FIGURE 7 is not obtained immediately, the installer need only shift the slab S back and fourth until the disc 27 does locate the kerf 35. As the parts come together, the curved surfaces serve to guide the slab S into position and thereby controllably lower the resilient strip 46 into load bearing relationship with the leg 25 of the bracket 16. Once the disc 27 mates with the kerf 35 the installer shifts the stone S until the final aligned horizontal position is reached.
The upper edge 23 of the stone S is next brought up adjacent the building to a plumbed position and then the bracket or brackets 16 are brought down into engagement with the kerfs 35a by temporarily loosening the bolts 62. As the brackets 16 are brought down, the curved surfaces of the kerfs 35 serve to guide the disc 27 into the proper horizontal position by movement of the bracket 16 with respect to the bolt 62 by means of the slotted aperture 26a. The installer then visually locates the disc 27 both horizontally and vertically (spaced slightly above the upper edge 23 of the slab S below as shown in FIGURE 6) and tightens the bolts 62 into locked position. Now, the final plumbed position of the stone S is determined and holding this position the mortar 50 and the rubber compound 51 are inserted in the respective kerfs 35, 35a to complete installation of the first slab S. From here the next slab S above is positioned on the bracket 16 by mating the upper portion 28 of the disc 27 and the installation process just described is repeated. At the top slab S adjacent the roof R because of the restriction of space, it is desirable to first place the upper portion 28 of disc 27 into position within the kerf 35a before bringing the slab S into the plumbed position and then attach the bolt 62 to the bar from the interior side of the mullion 10.
From the foregoing description of the present invention, it will now be clear to those skilled in the art that real results and advantages over the prior art are obtained by the described system. That is, the use of semicircular kerfs 35, 35a in conjunction with the anchoring disc 27 provides a system wherein the strength of the upper and lower edges 22, 23 of a slab S are not materially'weakened. Further, each slab S is individually and resiliently supported by the resilient strip 46 so that the eifects of expansion and contraction as well as vibration are eliminated; i.e., each slab S being capable of the required movement and fiexure resulting from these forces. Furthermore, an additional advantage is the provision of clearance spaces between the anchoring disc 27 and the kerfs 35, 35a for gaining final alignment and plumbing of the slabs S; such spaces being respectively filled with the mortar 50 to stabilize the lower edge 22 of the slab S and with a resilient rubber compound 51 to insure the required fiexure and movement at the upper edge 23.
In this disclosure, there is shown and described only the preferred embodiment of the invention, but, as aforementioned, it is to be understood that the invention is capable of various changes or modifications within the scope of the inventive concept.
1. A supporting and anchoring system for a building facing including a plurality of contiguous slabs each having upper and lower operative edges comprising fastening means attached to said building, a plurality of spaced angle brackets carried by said fastening means each having one leg thereof extending outwardly from said building, said one leg being positioned in a horizontal plane for engaging the lower edge of one of said slabs in cantilever supporting relationship, a substantially circular disc fixed on said one leg and extending perpendicular thereto, said disc presenting first and second semicircular portions extending above and below said horizontal plane, respectively, substantially semicircular kerfs formed in said upper and lower edges of said slab and positioned corresponding to said first and second semicircular portions, said first portion engaging the kerf in the lower edge of said slab and said second portion engaging 'the kerf in the upper edge of the adjacent slab below in anchoring relationship, whereby said slabs are supported and anchored without materially weakening of said upper and lower edges of said slabs.
2. The combination of claim 1 wherein is provided at least a pair of said brackets in said horizontal plane to support said slabs at spaced points.
3. The combination of claim 1 wherein is further pro vided a clearance cutout extending along said lower edge of said slab in the area substantially corresponding to said angle member and a strip of resilient material in said cutout for engagement with said one leg of said angle member, whereby said slabs are resiliently supported for movement and flexure as required.
4. The combination of claim 3 wherein said clearance cutout is provided only along the rear of said lower edges, and said disc is positioned at the outer limit of said one leg whereby said leg engages said slab in load bearing relationship only along said resilient strip.
5. The combination of claim 1 wherein is provided a clearance space between said kerfs and the corresponding semicircular portions to allow for final adjustment and plumbing of said slabs.
6. The combination of claim 5 wherein said clearance space of said kerf in said lower edge is filled with compressible mortar to surround said first semicircular portion for stabilizing said slabs along said lower edge.
7. The combination of claim 6 wherein said mortar comprises a mixture of substantially two parts cement to one part ground limestone for maximum stability without rigidity.
8. The combination of claim 5 wherein resilient material fills said clearance space of said kerf in said upper edge to surround said second semicircular portion, whereby said slabs are resiliently anchored along said upper edge.
9. The combination of claim 1 wherein the center axis of each of said kerfs is spaced from the corresponding edge in the direction away from the kerf to allow for increased adjustment in the horizontal plane.
10, The combination of claim 1 wherein said kerfs are spaced from the corners of said slabs for minimum weakening of said edges.
11. A supporting and anchoring bracket for thin facing slabs having substantially semicircular kerfs formed in the upper and lower operative edges thereof, comprising an angle member having one leg for engaging said lower edge of one slab in supporting relationship, and a substantially circular disc mounted on said one leg and extending perpendicular thereto, said disc presenting first and second semicircular portions extending above and below said leg for respectively engaging kerfs in the lower edge of one slab and in the upper edge of an adjacent slab below in anchoring relationship, whereby said slabs may be supported and anchored without materially weakening of said upper and lower edges of said slabs.
References Cited UNITED STATES PATENTS 581,940 5/1897 Pelton 52509 1,552,392 9/1925 Cowing 52573 2,132,547 10/1938 ,Sohn 52379 X 2,413,183 12/1946 Hosbein 52714 X 2,860,504 11/1958 Sinner et al. 52509 X 3,319,983 5/1967 Zibell 52488 X FOREIGN PATENTS 118,080 6/1930 Austria.
488,794 1/ 1954 Italy.
ALFRED C. PERHAM, Primary Examiner US. Cl. X.R.