CA1298690C - Apparatus for attaching roofing membrane to a structure - Google Patents

Abstract

Abstract of the Disclosure A roof membrane anchoring system in accordance with the present invention includes an anchoring plate with a roof engaging surface and a top surface that can be attached to an existing structure. The anchoring plate has an axial opening therein into which a lip extends. An insert is inserted into the axial opening in the anchoring plate once a roofing membrane is inserted into the axial opening in the plate. The insert has a greatest diametrical dimension. The anchoring system is designed to assume a first state wherein the greatest diametrical dimension of the insert is slightly less than the inside diameter of the axial opening and slightly greater than the inside diameter of the lip extending into the axial opening and a second state wherein the greatest diametrical dimension of the insert is slightly less than the inside diameter of the lip which extends into the axial opening.

Description

6~005-307 3~Z~9~

APPARATUS FOR ATTACHING ROOFING MEMBRANE TO A STRUCTURE
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CROSS REFERENCE TO RELATED APPLICATION

:' :~' :~ Back round of the Invention : . This invention relates to an apparatus for attaching roofing membrane to a structure, and more particularly to an apparatus that does not require puncturing of the ~: roofing membrane.
There are a wide variety of roofing systems used for various types of buildings. For larger buildings with generally flat roof surfaces or domed surfaces, flexible ::~ sheet material, for example, EPDM rubber membrane, is becoming increasingly popular due to its many well known ~; advantages. This membrane-type roofing is attached to the ~ structure by basically four different systems. The first : system is an adhered system wherein the entire qurface is coated with suitable cement and the membrane is then :

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~9 stretched across the surface with separate layers of membrane being overlapped and cemented to form a watertight barrier. This system is very time consuming and expensive due to the cost of cement and the labor in applying the cement. In the partially adhered system bonding takes place at only special plate areas and at the overlap between the sheeting material. This system suffers from many of the same deficiencies as the adhered system. In a ballast system, membrane is laid on top of the roof and a layer of small stones is placed across the roof to hold the membrane to the roof. There are two separate types of mechanically fastened systems. One system incorporates battens which are arranged over the overlapping portions of the sheeting material and then secured to the roof with a layer of membrane being placed over the battens and adhered to the batten and the underlying membrane to form a watertight barrier. A
second type of mechanical fastening system incorporates anchors which are spaced across the roof and the membrane is then anchored at specific locations to the roof. Many of these anchoring systems require penetration of the roof membrane in the process of anchoring the membrane to the structure. Thus, an additional sealing component must be added increasing the time and expense necessary for attaching the membrane to the roof. Some anchoring systems have been adapted to eliminate the need for penetrating the roofing membrane. However, these anchoring systems are either complicated and require hardware that must be manufactured at considerable expense or can be easily damaged when workers are required to walk across the roof.
Various methods and devices for attaching roofing membrane to a structure are disclosed by the following group of patent references. Each reference pertains in ~;~9~6~0 one way or another to attaching roofing membrane to a surface though some references are believed to be more relevant to the present invention than others. It is believed by the applicant that the following references are illustrative of the many anchoring systems currently - available.
Patent No. Patentee 4,519,175 Resan ~,543,758 Lane 4,502,256 Hahn 4,520,606 Francovitch 4,455,804 Francovitch 1,609,328 Fed. Rep. of Germany 2,330,901 France Resan discloses a lubricated roofing membrane fastener which does not require that the roofing membrane be penetrated in order to attach it to the structure.
However, Resan does not disclose the precise invention claimed in this application and suffers from being easily tripped over or having the cover 35 kicked off when workers are required to cross the roof.
Lane discloses a rail and cap strip for securing rubber roof membrane to a deck without fastener penetrations. Lane appears to be a combination of a batten system and anchor system. The only relevancy to the present invention is that no penetration of the membrane is required.
Hahn discloses an arrangement for securing a flexible web to a walling means. The invention disclosed in Hahn does not require penetration of the flexible web and that is believed to be the extent of the relevancy to the present invention. Hahn requires a substantial portion of : :

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the anchoring means to remain above the web material allowing the anchor to be damaged or tripped over when workers are required to walk across the roof.
Francovitch '606 discloses a roof membrane and anchoring system using dual anchor plates. FIGS. 5-9 disclose anchoring mechanisms which do not require the penetration of the roofing membrane. Also Francovitch discloses a low profile anchoring system which, to a certain extent, alleviates some of the problems inherent with other anchoring systems.
Francovitch '804 discloses a membrane anchor. The relevancy of '804 is believed to be limited to disclosure of a plate in FIGS. 1-5 which has the same general outward shape as the anchoring plate component of the present invention.
The German patent discloses a wide variety of methods and apparatus for attaching sheeting material to a structure such as a tunnel. FIG. 9 illustrates a three-part device which does not require penetration of the sheeting material. However, it appears that the device is inserted in a bore drilled into the surface and therefore would require substantial time in placing the device. Additionally, the device disclosed in FIG. 9 does not incorporate the use of compression cuts in order to ease the insertion of the cap within the anchor plate.
The French patent illustrates an anchoring mechanism which uses a cap that is inserted into a hole in the structure with the cap being compressible to be inserted into the hole and then expandable to remain secured within the hole. The French patent requires a large hole to be drilled or bored in the existing structure, and apparently in the roofing membrane, so that any failure of the anchoring mechanism would almost invariably lead to leaks in the roof of the structure.

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From the foregoing, it is clear that none of the references cited specifically solves all of the problems inherent in anchoring mechanisms for ro~fing systems.
Additionally~ none of the cited references either incorporate or suggest the combination of all of the elements of the present invention.

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Summar~ of the In~ention The present invention provides an anchoring system for securing a roof membrane to a structure, the anchoring system comprising an anchoring plate formed to include a membrane-receiving chamber, means for fastening the anchoring plate to the structure, a cap configured to fit in the membrane-receiving : chamber, the cap including an inner member positioned to trap a roof membrane disposed in the membrane-receiving chamber between the anchoring plate and the cap and an outer member, the inner member being formed to include at least one compression cut situated to lie in the membrane-receiving chamber of the anchor-ing plate upon placement of the cap therein and arranged to permit flexure of the inner member in a radially outward direction, the cap being formed to include a central aperture extending through the outer and inner members and having a plug-receiving opening . in the outer member, and a plug including means positioned in the central aperture for flexing the inner member in a radially out-ward direction toward the anchoring plate to establish a locked connection between the cap and the anchoring plate so that a roof membrane is retained in the membrane-receiving chamber without penetrating the roof membrane.
The invention also provides an anchoring system for securing a roof membrane to a structure, the anchoring system comprising an anchoring plate formed to include a chamber, means for fastening the anchoring plate to the structure, a cap having an inner end positioned in the chamber to engage a roof membrane ' ~
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- 6a - 6~005-307 inserted kherein and an outer end, the cap being formed to in-clude a first interior wall defining a central aperture extending in an axial direction through the inner and outer ends and having a first diameter, a second interior wall defining an upwardly opening cylindrical cavity having a second diameter greater than the first diameter, and an axially outwardly facing annular lip extending in a radial direction between the first and second interior walls, and a plug including a body member configured to fit in the central aperture and flange means situated in the up-wardly opening cylindrical cavity for engaging the axially outwardly facing annular lip to position the body member in close-fitting engagement with the inner end of the cap to urge the inner end of the cap in a radially outward direction toward the anchoring plate so that a roof membrane disposed in the chamber is trapped therebetween without penetrating the roof membrane.
The invent~ion further provides an anchoring system for securing a roof membrane to a structure, the anchoring system comprising an anchoring plate formed to include a cap-receiving chamber, means for fastening the anchoring plate to the structure, a cap including a first interior wall defining an outer aperture having a first diameter, a second interior wall defining an inner aperture having a second diameter less than the first diameter, and a necked-down frustoconical wall defining a passageway lying between the outer and inner apertures and cooperating to provide a plug-receiving cavity in the cap, and a plug situated in the plug-receiving chamber, the plug including means for urging the . ~

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- 6b - 64005-307 cap toward the anchoring plate to establish a locked connection therebetween so that a roof membrane disposed in the cap-receiving chamber between the cap and the anchoring plate is retained securely therein without penetrating the roof membrane.
There may be at least one protrusion extending from the bottom surface of the anchoring plate which will penetrate insulation on the roof being covered to prevent the anchoring plate rom rotating when it is attached to the roof by linear fastenérs.
The anchoring plate may have fastening holes the~ethrough to allow affixation to the roof with linear fasteners. The fastening holes may have wings and caps with tabs sized to fit within the wings may be inserted in the fastening holes to prevent the linear fasteners from backing out of the roof.
There are many possible variations of the insert, one of which is a cap that has a disk-shaped top and a cylindrical body with a circumferential protrusion at the bottom of the cylindrical body. Compression cuts are located in the apparatus to allow the apparatus to attain a first state and a second state.
In the first state, the outside diameter of the cylindrical body is slightly less than the inside diameter of the lip in the axial opening of the anchoring plate. In the second state, the greatest diametrical dimension of the cylindrical body and the circum-ferential protrusion is slightly less than the inside diameter of the lip in the axial opening in the : ., ~2~69~

anchoring plate. When the cap is inserted into the anchoring plate, the apparatus conforms to the first state. One variation of the present invention incorporates a cavity which extends through the cylindrical body and the disk to form a ring type cap which is inserted into the anchoring plate and then a plug having a diameter approximately equal to the diameter of the cylindrical opening is inserted into the ring cap, thereby locking the cylindrical body in the first state.
Further embodiments of the invention include a base plate as described above and an insert capable of attaining two states. In the first state, the greatest radial dimension of the insert is slightly less than the inside diameter of the axial opening but slightly greater than the inside diameter of the lip in the axial opening.
In the second state, the greatest radial dimension of the insert is slightly less than the inside diameter of the lip in the axial opening, thereby allowing insertion of the insert into the axial opening. After the roofing membrane is stretched across the roof and a portion of the membrane is inserted in the axial opening of the base plate, the insert, in the second state, is inserted in the axial opening and expanded to the first state in which it i~ locked to secure the roofing membrane to the structure. Among the various designs of the insert are:
an O-ring and a plug that, when inserted in the O-ring, expands the O-ring to the first state and locks it therein; a disk of rubber or like material sandwiched between two inflexible disk-shaped plates so that when the plates are compressed toward each other the rubber material expands from the second state to the first state;
and a C-ring or snap-ring that is compressible from the first state to the second state b~ an appropriate force and which returns to the first state when the force is no ~298~

longer applied.
One object of the present invention is to provide a low profile system for attaching roofing membranes to structures~
A second object of the present invention is to provide a system for attaching roofing membrane to an existing structure which does not require penetration of the membrane.
A further object of the present invention is to provide a low cost and economical system for attaching roofing membrane to an existing structure.
Yet another object of the present invention is to provide a system for attaching roofing membrane to an existing structure which does not require extensive modification to the existing structure.
~ elated objects and advantages of the present invention will be apparent from the following description.

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_9_ Brief Description of the Drawings :;
FIG. l is a cross-.sectional view of an anchoring plate in accordance with the present invention.
FIG. 2 is a partial top view of the anchoring plate of FIG. 1.
FIG. 3 is a top view of a first cap in accordance with the present invention.
FIG. 4 is a side view of the cap of FIG. 3.
FIG. 5 is a cross-sec-tional view along lines 5-5 of FIG. 3.
FIG. 6 is a top view of a second cap in accordance with the present invention.
FIG. 7 is a cross-sectional view of a plug to be used with the cap of FIG. 6.
FIG. 8 is a cross-sectional view of the cap of FIG. 6.
FIG. 9 is a cross-sectional view of the system described in the present invention during insertion of the cap into the anchoring plate.
; FIG. lO is a cross-sectional view of one embodiment of the present invention when the roofing membrane is completely anchored to the structure.
FIG. 11 is a blown-up view of a portion of FIG. 10.
FIG. 12 is a top view of an additional embodiment of an anchoring plate in accordance with the present invention.
FIG. 13 is a cross-sectional view along line 13-13 of FIG. 12 and also includes a cross-sectional view of an additional cap and plug arrangement.
FIG. 14'is a partial bottom view of the anchoring ; plate of FIG. 12.
FIG. 15 is a cross-sectional view of a separate embodiment of an anchoring plate in accordance with the ~ present invention.
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FIG. 16 is a cross-sectional view of one embodiment of an insert in accordance with the present invention.
FIG. 17 is a top view of an embodiment of an insert in accordance with the present invention.
FIG. 18 is a cross-sectional view of an insert in accordance with the present invention.
FIG. 19 is a cross-sectional view of the FIG. 18 insert with the insert in a first state.
FIG. 20 is a top view of an insert in accordance with the present invention.

Descri tion oE the Preferred Embodiment P
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to descr;be the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
Referring to FI&S. 1, 2, 9, 10, 12, 13, 14 ~ 15, there are illustrated various views of various embodiments of an anchoring plate 20, 20A & 20B (hereinafter referred to collectively as 20 unless otherwise specified) for attachment to a structure 22 (FIGS. 9 and 10) such as the roof of a large building. Anchoring plate 20 is a disk 24 with a bottom surface 26 which may be hollowed out, as in anchoring plate 20A (FIG. 14), or which may be substantially planar as in 20 or 20B, and a top surface 28 which may be radiused as in anchoring plates 20 ~ 20A. As can be seen from the drawings, when the top surface is convexly radiused there is a substantially thicker center portion with the anchoring plate 20 being thinner near the peripheral edge 30. Extending circumferentially around the peripheral edge is a thin planar ring 32 which extends between the peripheral edge 30 and peripheral edge of the radiused top surface 28. There is an axial opening 34 at the center of anchoring plate 20 which is cylindrical.
For purposes of convenience in describing the invention, axial opening 34 is defined as that part of the opening at the center of disk 24 wi~h the greatest inside diameter.

If axial opening 34 extended through the top surface with no structure extending into the axial opening, it would appear from the top view to be illustrated as dotted line 36 in FIGS. 2 & 12. However, axial opening 34 does not extend through the top surface 28 as a lip 38 extends radially into axial opening 34 from the radiused top surface 28. Lip 38 extends into axial opening 34 around the entire circumference of axial opening 34 as is best illustrated in FIGS. 2 & 12. Lip 38 has a cyliT~drical side surface ~0 and a ring-shaped bottom surface 42. A
bottom flange 44 may also extend radially into axial opening 34 as in FIG. 1. Bottom flange 44 has a ring-shaped top surface 46. Therefore, it should be understood that bottom flange 44 extends radially into axial opening 34 around the entire circumference of axial opening 34. When a bottom flange 44 is incorporated into the anchoring plate, a channel 48 is defined by ring-shaped bottom surface 42 of lip 38, ring-shaped top surface 46 of bottom flange 44 and radial axial opening 34O Extending through the lower surface 50 of axial opening 34, there is an axial attachment hole 52 through which an appropriate linear fastener 54 (FI&S. 9 and 10) may be inserted to attach anchoring plate 20 to structure 22. It should be understood that the choice of linear fastener 54 will depend upon the type of structure to which the anchoring plate is to be attached. Among the typical types of linear fasteners 54 are nails, screws, and rivets, however, any appropriate linear fastener for the type of structure 22 may be incorporatedO A plurality of alternate attachment holes 56 are also provided.
Testing of the anchoring plate 20 illustrated in FIGS.
1-3 and 9-10 has revealed that in extreme conditions the linear fastener 54 may back out of the structure slightly, thereby allowing the anchoring plate 20 to rotate about i ~ 6 linear fastener 54 if secured only through attachment hole 52. rrwO problems may arise from such a situation. First, if the anchoring plate 20 rotates, additional stresses are put on the sheeting material 58 received in opening 34.
These stresses may cause sheeting material 58 to tear, destroying the watertight integrity of a roof attached to a structure with this system. Second, if the linear fastener backs out of the structure sufficiently, the head of the linear fastener may penetrate the roofing membrane.
To prevent rotation of anchoring plate 20, a pair of protrusions 65 may be incorporated into the underside of the anchoring plate 20A as in FIG. 13. These protrusions engage the structure 22 and penetrate into any insulation covering the structure to prevent rotation of the anchoring plate.
As is illustrated in FIGS. 12 & 13, attachment hole 52 and alternate attachment holes 5~ may have an inside diameter 53 in that portion of the attachment hole closest to the top surface which is large enough to accommodate the head of a linear fastener and an inside diameter 55 closer to the bottom surface of the anchoring plate which is smaller than the head of a linear fastener. A wing 57 which is cut into the body of the anchoring plate as illustrated may extend radially from the portion of the attachment hole with the greater inside diameter. An anchor hole cap 59 with a cylindrical body 61 (sized to be snugly received in greater inside diameter of the attachment hole 52 or alternate attachment holes 56) and a tab 63 ~sized to be received in wing 57) may be iDserted into the anchoring plate to reduce the possibility that the linear fastener 54 will back out of the structure and penetrate a roofing membrane 58 layed over the anchoring plate.
Referring to FIGS. 3-11 and 13, there is illustrated a .

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cap 60 which is inserted into anchoring plate 20 to secure the roofing membrane 58 (FIGS. 9 and 10) to anchoring plate 20~ ~eferring more particularly to FIGS. 3-5, a cap 60 of a first embodiment is illustrated. Cap 60 consists of a resilient plastic cylindrical body 62 having a top end 64 and bottom end 660 Cylindrical body 62 has an outer wall 68 and an inner wall 70. Cylindrical body 62 has a longitudinal axis 72 about which inner wall 70 defines a concentric downwardly opening cylindrical cavity 74. Attached to the bottom end 66 is a V-shaped protrusion 76 which extends radially beyond the outer wall 68 around the entire circumference of cylindrical body 62. V-shaped protrusion 76 tapers inwardly from its top 75 to its bottom 77. A plurality of compression cuts 78 extend through the cylindrical body and the protrusion 76. Attached to the top end 64 of the cylindrical body 62 is a disk 80 which has an outside diameter 99 (FIG. 11) greater than the greatest diametrical dimension 97 of cylindrical body 62 and protrusion 76. This disk 80 may be constructed with the radiused corners 82.
Referring to FIGS. 6-8, there is illustrated a second embodiment of a cap 60 in accordance with the present invention. This cap also has a resilient plastic cylindrical body 62 with a top end 64 and a bottom end 66 as well as an outer wall 68, an inner wall 70 and a longitudinal axis 72. However, this cap differs in that downwardly opening cylindrical cavity is also an upwardly opening cylindrical cavity 83 which is concentric about longitudinal axis 72. Since the cavity extends through what was the disk 80 in the first embodiment, in the second embodiment, there is a ring 84 attached to the top end 64 of the resilient cylindrical body 62.
Additionally, there is a plug 86 sized to fit within the cylindrical cavity 83.

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FIG. 15 illustrates an additional embodiment of cap 60A. This embodiment is made of flexible rubber and is basically the same design as the previously described embodiment. Cap 60A differs from the previously described embodiments in that the compression cuts do not extend through protrusions 76, but onl~ through the cylindrical body 62. Also protrusions 76A are rounded rather than V-shaped as in the previous cap. These differences reduce the likelihood of accidental puncture and make cap 60A the preferred embodiment of the insert.
The plug ~6 has a taper 88 near the bottom 90 of the side walls 87 to ease the insertion of the plug into the cylindrical cavity 83. Additionally, in the bottom 90, there is a recess 92 of sufficient size to accommodate the head of the linear fastener 54. The plug 86 is of a length sufficient to allow the top surface 91 to be flush with the top surface 89 of ring 84 when the plug is inserted into cap 60 as is best illustrated in FIG. 10.
FIGS. 16-20 illustrate alternative embodiments of an insert to be placed within the anchoring plates 20, 20A
and 20B as previously described. Each of these embodiments provides for locking a roofing membrane witbin the anchoring plate through various methods. FIGS. 16 &
17 illustrate the use of a rubber 0-ring lOlA & B which would be inserted into the axial opening in the anchoring plate after a roofing membrane is inserted in the opening. Upon insertion of rubber 0-ring 101, the 0-ring is then expanded and locked in a position where it engages lip 38 and thereby secures membrane within the anchoring plate. Expansion of the O-ring is caused by a plug 102A
or plug 102B of appropriate design. With an O-ring like that illustrated in lOlA where the interior surface of the O-ring is smooth, a tapered plug such as 102A would be inserted into the 0-ring to expand the O-ring. Plug 102A

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may have notches 103 for seating of the 0-ring lOlA
therein, thereby locking the O-ring in an expanded state.
~ ith O-ring lOlB, there are double ratchet teeth 104 and 105 inside the O-ring. Plug 102B has ratchet teeth 106 on its outside diameter. Plug 102B is inserted in O-ring lOlB and is rotated slightly until tooth 106 on th plug rides up tooth 104 on the O-ring and dops within the notch separating tooth 104 from tooth 105. This slight rotation of the plug expands the 0-ring and increases the outside diameter of the 0-ring allowing it to be locked within the axial opening in the anchoring plate. Slot 107 is placed in the plug to allow the plug to be rotated by a straight blade screwdriver. A square, hex or Phillips hole may be incorporated instead of slot 107. A
configuration of the inside of O-ring lOlB and the outside configuraticn of plug 102B may be of various design so as to provide for the expansion of 0-ring lOlB.
FIG. 18 illustrates a compression plug 110 which may be inserted in axial opening of the anchoring plate.
Compression plug 110 consists of a block or disk 112 of rubber or synthetic material sandwiched between two plates 114 constructed oE rigid material such as steel. Plates 114 are arranged relative to one another so that a compression means 115, such as a nut and bolt, connect the two plates 114. As compression means 115 is used to bring plates 114 closer together, the block or disk 112 of synthetic material is deformed so that the outside dimension of plug 110 is increased. This increase in outside dimension causes the plug 110 to be locked in the axial opening of the anchoring plate, thereby securing the roofing membrane to the anchoring plate. Plug 110 is shown in a compressed state in FIG. 19.
FIG. 20 illustrates yet another insert Eor use in securing a roofing membrane to the anchoring plate. A

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simple C-ring or snap-ring 116 made of spring metal or like ma~erial may be compressed from the first state to a second state and inserted in axial opening in the anchoring plate. When the compression force on the C-ring or snap-ring 116 is released, the C-ring or snap-ring returns to the first state and thereby locks the membrane in the axial opening of the anchoring plate.
The interrelationship between the anchoring plate 20 and the cap 60 is best illustrated in FIGS. 9, 10 and 11.
As can be seen from FIG. 11, the outside diameter 93 of cylindrical body 62 is slightly less than the inside diameter 94 of cylindrical side surface of lip 38. The distance 95 between the bottom oE the disk 80 or ring 84 to the top of the protrusion 76 is slightly greater than the thickness 96 of the lip 38. The greatest dia~etrical dimension 97 of the cylindrical body 62 and the protrusion 76 is slightly less than the inside diameter 98 of axial opening 34. The outside diameter 99 of disk 80 or ring 84 is substantially greater than the inside diameter 94 of cylindrical side surface 40 of lip 38. These measurements are critical in order for the anchoring system to function properly. The utility of the compression cut 78 is best illustrated in FIGS. 9 and 10. Compression cut 78 is designed to allow the cylindrical body 62 of cap 60 to assume a first state illustrated in FIGS . 8, 4, 5, 10 and 11, wherein the sides 79 of the cut are parallel to one another. Additionally, the cap 60 can assume a second state best illustrated iD FIG. 9 wherein the sides 79 of the cylindrical compression cut 78 converge toward bottom end 66 of the resilient cylindrical body 62. In the second state, the greatest diametrical dimension 97 of cylindrical body 62 and protrusion 76 is diminished to be slightly less than the inside diameter 94 of cylindrical side surface 40 of lip 38. This allows for the cap 60 to .

2 ~ 6 be inserted into anchoring plate 20 after membrane 58 has been extended across the anchoring plate 20 and inserted into axial opening 34. Once the cap 60 is completely inserted into axial opening 34, the cylindrical body 62 resumes its first state and the sides 79 of the compression cut 78 are once again parallel (as illustrated by the dotted lines in FIG. 10) and the protrusion 76 is received in channel 48. At this time, if the second embodiment or third embodiment of cap 60 is used, plug 86 may be inserted into cylindrical cavity 83 and thereby lock cylindrical body 62 into the first state so that the cap 60 cannot be inadvertently knocked out of the anchoring plate 20. Plug 86 and cylindrical cavity 83 may be designed so that plug 86 is driven into cylindrical cavity 83 or so that either or both plug 86 and cylindrical cavity 83 will have threads 100 which will allow the plug 86 to be screwed into cylindrical cavi~y 83. These threads 100 are illustrated by the dotted lines in FIGS. 7 and 8, while a smooth sided plug 86 and cylindrical cavity 83 are illustrated in the remainder of the drawings illustrating the second and third embodiments of cap 60. As can be seen from FIGS. 9 and 10, the use of compression cut 78 and of the particular design of both the anchoring plate 20 and caps 60 allows the membrane 58 to be secured to the anchoring plate 20 which is secured to the structure 22 without membrane 58 being penetrated in any way so that the watertight integrity of membranP 58 is maintained.
FIG. 10 best illustrates that the anchoring system of the present invention is very low profile and therefore cannot be easily damaged by workers walking on the roof after or during installation. Anchor plate 20, because of radiused top surface 28, results in only slight and gradual deviation of the roof surface. Cap 60 does not ~%915 6~(~

protrude greatly beyond the roof membrane as only the thin ring 84 or disk 80 of cap 60 is not received within axial opening 34. Because so little of cap 60 protrudes above roofing membrane 58, there is very little chance that a blow sufficient to dislodge cap 60 could be administered by the foot of a worker walking on the roof.
It is envisioned that cap 60 and anchoring plate 20 may be manufactured or molded from a wide variety of materials. One material which is envisioned is a hard plastic because it is sufficiently flexible to be compressed, through the use of compression cuts 78, into the second state, yet rigid enough that once cap 60 and anchoring plate 20 are snapped together there will be secure attachment of roofing membrane 58 to structure 22.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.

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Claims (10)

1. An anchoring system for securing a roof membrane to a structure, the anchoring system comprising an anchoring plate formed to include a membrane-receiving chamber, means for fastening the anchoring plate to the structure, a cap configured to fit in the membrane-receiving chamber, the cap including an inner member positioned to trap a roof membrane disposed in the membrane-receiving chamber between the anchoring plate and the cap and an outer member, the inner member being formed to include at least one compression cut situated to lie in the membrane-receiving chamber of the anchoring plate upon placement of the cap therein and arranged to permit flexure of the inner member in a radially outward direction, the cap being formed to include a central aperture extending through the outer and inner members and having a plug-receiving opening in the outer member, and a plug including means positioned in the central aperture for flexing the inner member in a radially outward direction toward the anchoring plate to establish a locked connection between the cap and the anchoring plate so that a roof membrane is retained in the membrane-receiving chamber without penetrating the roof membrane.

2. The anchoring system of claim 1, wherein the inner member is formed to include a plurality of elongated channels arranged to lie in circumferentially spaced relation about an interior wall defining the central aperture and configured to open into the central aperture.

3. The anchoring system of claim 1, wherein an axially inner portion of the central aperture is formed in the inner member, the inner member includes a circular interior wall defining a boundary of the axially inner portion, and each compression cut is an elongated channel formed in the inner member to have an axially extending opening in the circular interior wall so that each channel opens into the axially inner portion of the central aperture.

4. An anchoring system for securing a roof membrane to a structure, the anchoring system comprising an anchoring plate formed to include a chamber, means for fastening the anchoring plate to the structure, a cap having an inner end positioned in the chamber to engage a roof membrane inserted therein and an outer end, the cap being formed to include a first interior wall defining a central aperture extending in an axial direction through the inner and outer ends and having a first diameter, a second interior wall defining an upwardly opening cylindrical cavity having a second diameter greater than the first diameter, and an axially outwardly facing annular lip extending in a radial direction between the first and second interior walls, and a plug including a body member configured to fit in the central aperture and flange means situated in the upwardly opening cylindrical cavity for engaging the axially outwardly facing annular lip to position the body member in close-fitting engagement with the inner end of the cap to urge the inner end of the cap in a radially outward direction toward the anchoring plate so that a roof membrane disposed in the chamber is trapped therebetween without penetrating the roof membrane.

5. The anchoring system of claim 4, wherein the cap is formed to include a plurality of elongated channels and each channel has a side opening formed in the first interior wall and a top opening formed in the axially outwardly facing annular lip.

6. The anchoring system of claim 4, wherein the first interior wall of the cap is formed to include interruptions therein.

7. The anchoring system of claim 4, wherein the cap is formed to include a plurality of compression cuts extending in an axial direction longitudinally through the inner member.

8. An anchoring system for securing a roof membrane to a structure, the anchoring system comprising an anchoring plate formed to include a cap-receiving chamber, means for fastening the anchoring plate to the structure, a cap including a first interior wall defining an outer aperture having a first diameter, a second interior wall defining an inner aperture having a second diameter less than the first diameter, and a necked-down frustoconical wall defining a passageway lying between the outer and inner apertures and cooperating to provide a plug-receiving cavity in the cap, and a plug situated in the plug-receiving chamber, the plug including means for urging the cap toward the anchoring plate to establish a locked connection therebetween so that a roof membrane disposed in the cap-receiving chamber between the cap and the anchoring plate is retained securely therein without penetrating the roof membrane.

9. The anchoring system of claim 8, wherein the cap is formed to include a plurality of compression cuts extending longitudinally through the first interior wall and the necked-down frustoconical wall.

10. The anchoring system of claim 8, wherein the first interior wall of the cap is formed to include interruptions therein.