Membrane Anchor

The present invention relates to an anchor for membrane used as a roofing material to prevent moisture from entering a structure such as a building.

It is conventional to apply membranes to roofs in order to prevent the entry of moisture into the structure of which the roof forms a part. These membranes are made of a synthetic, rubber-like material which is flaccid and waterproof and typically are 3/64" thick; they are supplied in rolls of 100' length and vary in width from 4'6" to 45'.

There have been four systems utilized for fastening the membranes. In the adhered system, a suitable cement is applied to the substructure surface and the rubber-like membrane applied over it; there is an overlap of one membrane sheet with the next, so as to provide a water impervious lap joint. A partially adhered method or system is used, wherein the bonding of the membrane takes place at special plate areas or locations. The ballasted system involves the holding down of the membrane with a layer of small stones. There is also used a mechanically fastened system, in which battens or other strips are placed on the membrane and are adhered, with complex systems for connecting the batten and sealing it. The batten is a strip of rubber or plastic material and is utilized in order not only to hold the sheet down against wind forces which might tend to lift it (as do the other systems) but also prevents or retards creeping movement of the sheet due to expansion and contraction. The seal utilized with the batten strip is a small membrane sheet which entirely covers the batten strip and which is glued down over the entire strip. All of the foregoing systems suffered either from expense of installation, or expense of materials, or both.

The present invention is directed to an anchor for a membrane, such as a rubber or rubber-like membrane sheet applied over a roof substrate. The anchor comprises a disc of rubber or rubber-like material, being resilient and water impervious. The disc has a relatively thick central region and an outwardly tapering peripheral region. An axial opening is provided at the center of the disc, and the lower surface of the disc is provided with annular grooves in the central region. Recesses are provided in the upper and lower surfaces in surrounding relationship to the axial opening. The lower surface of the disc, in the unstressed state, is inclined upwardly from the edge of the disc, to the juncture of the central and peripheral regions. A linear fastener is passed through the opening, with its head located in the recess in the upper surface. Sealing material may be deposited over the head, to prevent entry of moisture, and sealing material is deposited in the grooves, prior to the application of the disc to the membrane, to form a barrier against the inward penetration of moisture.

FIG. 1 is a cross-sectional view of a membrane anchor in accordance with the present invention, taken on the line A--A of FIG. 2.

FIG. 2 is a plan view of the membrane anchor of FIG. 1, showing the lower surface.

FIG. 3 is a plan view of the membrane anchor, showing the upper surface.

FIG. 4 is an enlarged view of one half of the membrane anchor as shown in FIG. 1.

FIG. 5 is a cross-sectional view showing a membrane anchor installed.

Referring now to the drawings, wherein like or corresponding references numerals are used to designate like or corresponding parts throughout the several views, there is shown in FIG. 1 a membrane anchor 1 of disc formation, and made of a resilient, water impervious material which is of a rubber or rubber-like substance. In the upper surface, located centrally, is a recess 2, and in the lower surface, there are a pair of annular grooves 3a and 3b. Extending axially through the center of the membrane anchor 1 is an opening 5 which communicates with the recesses 2 and 4.

FIG. 2 clearly shows the concentric annular grooves 3a and 3b on the lower surface of the membrane anchor 1, the recess 4 and the opening 5, while FIG. 3 clearly discloses the opening 5 and recess 2 in the upper surface.

As shown in FIG. 4, the membrane anchor 1 has a central region which is of uniform thickness, and it is in this region that the continuous annular grooves 3a and 3b are located, as well as the opening 5 and the surrounding recesses 2 and 4. The membrane anchor 1, adjacent and outwardly of the thicker central region, has a peripheral region which is of outwardly tapering thickness, the upper surface of the outer region being inclined downwardly towards the edge of the membrane anchor or disc 1, while the lower surface is inclined upwardly from the edge of the disc, when the disc is not stressed, to the juncture of the two regions. The angle of upward inclination is indicated by reference numerals 6 and will be seen to be a slight angle of a few degrees. The peripheral region is of substantially the same thickness as the central region at the juncture between them.

Referring to FIG. 5, there is shown the membrane anchor in installed position, in place on and engaging a membrane 10, which is supported by any conventional substrate member or members 11 and 12. A linear fastener 9 extends through the opening 5, and is of a type suitable for the particular substrate with which the membrane 10 is used. The head of the linear fastener 9 is in the upper recess, and a mass of sealing material is placed over the head of fastener 9, in engagement with the head of fastener 9 and the membrane anchor or disc 1. Prior to placing the membrane anchor or disc 1 against membrane 10, sealing material, such as mastic, generally designated by the numeral 7, will have been placed in the annular grooves.

To use the membrane anchor of the present invention, mastic or other sealing material is applied so as to fill the annular grooves, and then the membrane anchor is placed in position, engaging the membrane 10. The linear fastener 9 is then put in place: if it is a nail, it is driven in place, or it may by a type of blind fastener or screw fastener, depending upon the material of the substrate. There results a pushing downwardly of the central region, causing it to bear with substantial pressure against the membrane 10. This causes the mastic or sealing material 7 to flow outwardly, spreading to a certain extent outwardly towards the disc edge, thereby providing a seal against the entry of moisture towards the fastener 9. In addition, there is deflection of the peripheral region, due to the angle of inclination 6 of the lower surface and the resilient quality of the membrane anchor 1, thereby providing a hold down force over a very substantial area by the membrane anchor 1. Thereafter, the sealant mass 8 is applied, to prevent entry of moisture at the head of fastener 9.

The membrane anchors as shown in FIG. 5 may be applied at spaced locations, such as on four-foot centers. As a result, the herein disclosed membrane anchor and related elements provide a system which is economical to manufacture and economical to install, while providing great hold down characteristics for the membrane and, also, preventing the entry of moisture.