Patent Description:
The present invention relates to glazed panel wall constructions, such as curtain walls, storefronts, and the like and more specifically, to a pressure plate for retaining glazing panels in place against a frame in a weather-tight manner.

Glazing systems for curtain walls, storefront framing systems, and the like are known wherein a pressure plate retains a glazing panel in place against a frame member, such as a mullion. The mullions are anchored to the building and run between the floor slabs in a window wall application or past the floor slabs in a curtain wall application. Typically, a pair of gaskets is installed within grooves in the pressure plate, which is then fastened to the outer face of the frame member by screws. The gaskets bear against adjacent glazing panels, providing a seal against air and water leakage. A third gasket installed near the center of the pressure plate between the pressure plate and the frame member may also be utilized to provide an additional weather and thermal barrier, e.g., to prevent water and air from migrating from one side of the
mullion to the other and providing a thermal barrier between the pressure plate and the mullion. This type of glazing system is labor-intensive to install, requiring multiple separate components to be assembled. Over time, the gaskets may shrink, compromising the integrity of the installation.

A co-extruded pressure plate made from polymer materials is disclosed in <CIT> as an alternative to the more common use of multiple separate gaskets with a metal pressure plate. In order for the pressure plate to be extruded integrally with the gaskets, it must be made of a material that is compatible with the elastomeric gaskets. It is challenging to utilize a compatible combination of currently available polymers for co-extrusion that have sufficient strength through the temperature extremes experienced by buildings for this application. Fiberglass pultrusions have been proposed for pressure plate applications to reduce thermal transfer, but are not as strong and or as easy to fabricate as aluminum pressure plates. Aluminum alloy pressure plates have desirable mechanical and manufacturing properties, despite having greater thermal conductivity. Aluminum provides the integrity and stiffness to maintain clamping pressure during all extremes of weather that are experienced by the exterior of a building. Alternative glazing systems to those presently known therefore remain desirable for different applications and requirements. <CIT> discloses a glazing system comprising: infills; a pressure strip; and seals intermediate the infills and the pressure strip, wherein an insulating body is arranged between the seals.

The disclosed subject matter relates to a pressure plate assembly, according to claim <NUM>, for holding a glazing unit to a frame member, including: an elongated metal plate; and an elongated composite plate formed from a material having a thermal conductivity less than the metal plate, the composite plate and the metal plate aligned and coupled together to form a pressure plate assembly, the pressure plate assembly fastened to the frame member with the composite plate proximate the
frame member and the metal plate distal to the frame member, the pressure plate assembly pressing the glazing unit toward the frame member. According to the invention the pressure plate assembly has a pair of gaskets.

In another embodiment, the composite plate has a central isolator attached to and extending longitudinally and parallel to the composite plate along a length thereof.

In another embodiment, the composite plate has at least one rib extending therefrom toward the metal plate and the metal plate has a slot receiving the rib therein to couple the composite plate to the metal plate.

According to the invention, the composite plate has a pair of ledges extending along opposing side edges of the composite plate, the ledges embracing the metal plate there between.

In another embodiment, further including a cap, the cap attaching to the pressure plate assembly distal to the frame member.

In another embodiment, the frame member has a tongue and the pressure plate assembly has at least one aperture therein and further comprising a threaded fastener, the threaded fastener extending through the at least one aperture and being threadedly received in the tongue, the threaded fastener pushing the pressure plate assembly toward the glazing unit.

In another embodiment, further including a cap with peripheral edges, the cap covering the pressure plate assembly, the pressure plate assembly having a pair of opposed grooves, the opposed grooves receiving corresponding ones of the peripheral edges of the cap.

In another embodiment, the ledges are disposed at an acute angle relative to the composite plate and point in a converging direction.

According to the invention, each ledge has a land at a tip thereof extending toward the metal plate.

In another embodiment, the ribs have teeth disposed at an orientation that resists withdrawal of the ribs from engagement with the slot.

In another embodiment, the isolator abuts against the tongue dividing the space between adjacent glazing units.

In another embodiment, the composite plate has a pair of extensions extending from the isolator.

In another embodiment, further including a pair of ribs extending from a surface of the composite plate in a perpendicular direction, the ribs running lengthwise along the composite plate parallel to edges of the composite plate and the metal plate has a pair of receivers, the receivers receiving the pair of ribs, the metal plate nesting between the ledges.

In another embodiment, the metal plate has a central offset, the offset receiving a portion of the isolator therein while the pair of extensions abut flat portions of the metal plate on either side of the central offset.

In another embodiment, the central offset has a thicker wall than the flat portions of the metal plate.

In another embodiment, the gaskets and the isolator are adhered to the pair of extensions by an adhesive.

In another embodiment, the gaskets and the isolator are co-extruded with the pair of extensions.

In another embodiment, a glazing system for holding glazing units to a frame member, includes: an elongated metal plate; and an elongated composite plate formed from a plurality of polymers having a thermal conductivity less than the metal plate, the composite plate having a pair of gaskets and a central isolator attached to and extending longitudinally and parallel to the composite plate along a length thereof, the composite plate and the metal plate aligned and coupled together to form a pressure plate assembly, the composite plate having a pair of ribs extending therefrom toward the metal plate and the metal plate having a pair of slots receiving the pair of ribs therein to couple the composite plate to the metal plate, the composite plate having a pair of ledges extending along opposing side edges of the composite plate, the ledges embracing the metal plate there between, wherein the frame member has a tongue and the pressure plate assembly has a plurality of apertures therein and further comprising a plurality of threaded fasteners, the threaded fasteners extending through corresponding ones of the plurality of apertures and being threadedly received in the tongue, the threaded fastener pushing the pressure plate assembly toward the glazing unit, a cap with peripheral edges, the cap covering the pressure plate assembly, the pressure plate assembly having a pair of opposed grooves, the opposed grooves receiving corresponding ones of the peripheral edges of the cap, the pressure plate assembly fastened to the frame member with the composite plate proximate the frame member and the metal plate distal to the frame member, the pressure plate assembly pressing the glazing unit toward the frame member.

In another embodiment, the composite plate has a pair of extensions extending from the isolator and the metal plate has a central offset, the offset receiving a portion of the isolator therein while the pair of extensions abut flat portions of the metal plate on either side of the central offset, the central offset having a thicker wall than the flat portions of the metal plate and wherein the gaskets and the isolator are co-extruded with the pair of extensions.

In another embodiment, the ledges are disposed at an acute angle relative to the composite plate and point in a converging direction. According to the invention, each ledge has a land at a tip thereof extending toward the metal plate, and each of the gaskets covers an outside surface of a corresponding one of the ledges, surmounts an upper edge of the ledge and returns in a downward direction on an inside surface of the ledge, including the land, the gaskets sealing between the metal plate and the lands. The isolator may abut against the tongue dividing the space
between adjacent glazing units.

For a more complete understanding of the present disclosure, reference is made to the following detailed description of exemplary embodiments considered in conjunction with the accompanying drawings.

<FIG> show a pressure plate assembly <NUM> in accordance with an embodiment of the present disclosure and which includes a metal plate <NUM> and a composite plate <NUM>. The pressure plate assembly <NUM> is an elongated member that extends along the edges of glazing panels <NUM>, <NUM> (<FIG>), e.g., in the vertical, or horizontal directions, parallel to the mullions. The glazing panels <NUM>, <NUM> can be other than rectilinear, e.g., the pressure plate assembly <NUM> may be at an oblique angle relative to the horizontal or vertical. The metal plate <NUM> may be formed, e.g., extruded from an aluminum alloy, e.g., a <NUM> or <NUM> aluminum alloy. The composite plate <NUM> has a pair of extensions <NUM>, <NUM> that may be made, e.g., extruded, from a rigid polymer, such as, glass filled polypropylene, nylon or polyamide. The extensions <NUM>, <NUM> extend laterally (in the width direction) from a central thermal isolator <NUM> that may be made, e.g., extruded, from a flexible polymer, such as thermal plastic elastomer (TPE). The extensions <NUM>, <NUM> and the isolator <NUM> are elongated and capable of running parallel to the metal plate <NUM> when it is positioned over the edge of glazing panels <NUM>, <NUM> and running the length (or width) of the panels <NUM>, <NUM>. As depicted, there are two separate extensions <NUM>, <NUM> that attach to the isolator <NUM>. In an alternative embodiment, the extensions <NUM>, <NUM> and/or isolator <NUM> may be part of a single extrusion that extends across the entire width of the composite plate <NUM>. The extensions <NUM>, <NUM> each have a straight portion <NUM>, <NUM>, a ledge <NUM>, <NUM> and a rib 16R, 18R with retainer teeth 16RT, 18RT, respectively. The ribs 16R, 18R are received in slots 12S1, 12S2 provided in receivers 12R1, 12R2 of the metal plate <NUM>. The retainer teeth 16RT, 18RT have an orientation allowing insertion, but resisting withdrawal from the slots 12S1, 12S2. The receivers 12R1, 12R2 have a U-shaped cross-sectional shape and have outer grooves 12G1, 12G2 for receiving the gripping edges of a cap <NUM> as described below in reference to <FIG>. The receivers 12R1, 12R2 have rounded edges and tapered surfaces 12T1, 12T2 to facilitate slipping the cap <NUM> and ledges <NUM>, <NUM> thereover.

Gaskets <NUM>, <NUM> made from an elastomeric material such as TPE, flexible polyvinyl chloride, DuPont Alcryn®, or other suitable elastomer are formed, e.g., co-extruded, on the extensions <NUM>, <NUM> proximate the ledges <NUM>, <NUM> on surfaces 16D, 18D distal to the ribs 16R, 18R, respectively. In another embodiment, the gaskets <NUM>, <NUM> may be separately formed and then adhered to the extensions <NUM>, <NUM> by an adhesive or thermal welding. The gaskets <NUM>, <NUM> have varying thickness over the width thereof and faces 22F, 24F permitting increased contact area with a glazing panel (<FIG>) in response to increased pressure, preferentially starting to seal at the outer edges 22E, 24E and then forming a wider sealing area in an inward direction (toward the central isolator <NUM> in the width direction). Hollows <NUM> and <NUM> in the gaskets <NUM>, <NUM> make them more compliant and responsive to increased pressure. In a similar way, the face 20F of the thermal isolator <NUM> has a V-shaped configuration and a hollow <NUM> that makes the thermal isolator <NUM> more compliant when pressed against a frame member <NUM> (<FIG>). The gaskets <NUM>, <NUM> extend along an outer surface 16Q, 18Q of the ledges <NUM>, <NUM>, surmount an end 16T, 18T of the ledges and extend along an upper inner surface 16I, 18I of the ledges <NUM>, <NUM>. The ledges <NUM>, <NUM> have a land (prominence) 16P, 18P at the ends thereof. The ledges <NUM>, <NUM> are disposed at an angle A relative to the straight portions <NUM>, <NUM> and converge inwardly. When the ribs 16R 18R are pressed fully into the slots 12S1, 12S2, terminal surfaces 22T, 24T of the gaskets <NUM>, <NUM> are substantially parallel to and proximate to the grooves 12G1, 12G2.

The metal plate <NUM> has a central offset 12C between flat portions 12F1, 12F2. The offset 12C may have a greater wall thickness than the flat portions 12F1, 12F2 to provide greater rigidity for the metal plate <NUM>. The offset 12C also accommodates a portion of the thermal isolator <NUM>, such that the body of the thermal isolator <NUM> can accommodate the inner ends 16E, 18E of the extensions <NUM>, <NUM> therein, while the extensions <NUM>, <NUM> abut against the flat portions 12F1, 12F2 of the metal plate <NUM>. The registration of the offset 12C with the thermal isolator <NUM>, the ribs 16R, 18R with the slots 12S1, 12S2 and the ledges <NUM> and <NUM> embracing the metal plate <NUM> proximate the receivers 12R1, 12R2, all contribute to establishing a predetermined relative orientation between the metal plate <NUM> and the composite plate <NUM>.

The composite plate <NUM> may be pre-assembled in a manufacturing facility rather than at the job site. Similarly, the composite plate <NUM> and the metal plate <NUM> may be assembled to form the pressure plate assembly <NUM> in a manufacturing facility. Alternatively, the composite plate <NUM> and the metal plate <NUM> may be assembled to form the pressure plate assembly <NUM> in the field, since assembly may be accomplished by a press-fit. In one alternative, the composite plate <NUM> and the metal plate <NUM> may be adhered to one another by an adhesive. The parts of the composite plate <NUM>, such as a extensions <NUM>, <NUM>, the thermal insulator <NUM> and the gaskets <NUM>, <NUM> may be produced separately and then assembled and adhered to one another using adhesives or thermal (plastic) welding. In another alternative, the parts of the composite plate <NUM>, such as extensions <NUM>, <NUM>, the thermal insulator <NUM> and the gaskets <NUM>, <NUM> may be produced and adhered to one another simultaneously by co-extrusion. Co-extrusion techniques are known to those skilled in the art wherein pellets of the different polymers, e.g. flexible polyvinyl chloride and glass-reinforced polyvinyl chloride, are placed in separate screw presses, heated, and forced as molten material through separate cavities of an extrusion press. The different polymers are forced through different ports of an extrusion die and brought together as they exit the die to form a unitary extrusion (co-extrusion).

In another alternative, the composite plate <NUM> may be produced by additive manufacturing (3D printing) methods.

<FIG> is a cross-sectional view of the pressure plate assembly <NUM> holding glazing panels <NUM>, <NUM> against a frame member <NUM>, such as a mullion. An attachment tongue <NUM> with a race 36R (slot for accommodating fasteners) extends from front plate 34P of the frame member <NUM>. The fastener, e.g., a threaded bolt <NUM> retains the pressure plate assembly <NUM> and presses it against the glazing panels <NUM>, <NUM> when the bolt <NUM> is tightened. Apertures extend through the pressure plate assembly <NUM> (including through the metal plate <NUM>, the composite plate <NUM> and the isolator <NUM>) at intervals along its length, e.g., every <NUM> inches, to accommodate a plurality of bolts <NUM>. In the instance where the composite plate <NUM> and the metal plate <NUM> are matched in length, the holes in the composite plate <NUM> (in the isolator) may be pre-formed such that when terminal edges of the metal plate <NUM> and the composite plate <NUM> are aligned and they are pressed together to assemble the plate assembly <NUM>, the holes for the fasteners will align. In another alternative, the holes through the composite plate <NUM> may be made, e.g., by drilling after the metal plate <NUM> and the composite plate <NUM> are assembled together. In a further alternative, the holes through the composite plate (through the isolator <NUM>) can be made when the fastener <NUM> is inserted, i.e., by the fastener <NUM> making its own hole by piercing through the isolator <NUM> when the pressure plate assembly <NUM> is installed. Inner gaskets <NUM>, <NUM> intermediate between the glazing panels <NUM>, <NUM> and the frame member <NUM>, provide a weather seal, thermal insulation and cushioning of the glazing panels <NUM>, <NUM>.

A cap <NUM> may be placed over the pressure plate assembly <NUM> to provide a finished look and improve thermal and weather resistance. The cap <NUM> is made from a material, such as an aluminum alloy or a polymer that has a degree of elasticity sufficient to allow the cap <NUM> to deform, permitting the edges 44E to slip over the metal plate <NUM>, and enter and grip the grooves 12G1, 12G2. In one embodiment, the gasket surfaces 22T and 24T may seal against the edges 44E of the cap <NUM> to reduce air and water intrusion into the space under the cap <NUM>, providing a weather and thermal barrier. The pressure plate assembly <NUM> aids in reducing thermal transfer and weather infiltration through and around the cap <NUM> as indicated diagrammatically by arrow T1, through the pressure plate assembly <NUM>, (T2), between the glazing units <NUM>, <NUM> and the pressure plate assembly <NUM> (T3), through the glazing units <NUM>, <NUM> and pressure plate assembly <NUM> (T4) and by convection on either side of the tongue <NUM> (T5 and T6).

An aspect of the present disclosure is to produce a pressure plate assembly <NUM> that combines the beneficial attributes of a aluminum pressure plate (metal plate <NUM>) with those of a co-extruded polymer pressure plate (composite plate <NUM>), which features the gaskets <NUM>, <NUM> and the central thermal isolator <NUM>. The metal plate <NUM> provides the structural support associated with traditional pressure plates, while the composite plate <NUM> provides the desired sealing and thermal isolation properties, while simultaneously allowing easy and reliable installation. The composite plate <NUM> (with lower thermal conductivity) is integrated into a single unit (is unitized), providing a continuous, uninterrupted thermal barrier across its width and across the width of the metal plate <NUM>, which is embraced by the ledges <NUM>, <NUM>. When the composite plate <NUM> is assembled to the metal plate <NUM> and occupies a position between the metal plate <NUM> and the frame member <NUM>, it reduces thermal transfer there between. The composite plate <NUM> insures proper positioning of the isolator <NUM> and gaskets <NUM>, <NUM> when first installed, firmly holding same in position relative to the metal plate <NUM>. The integral composite plate <NUM> also resists shrinkage and movement of the isolator <NUM> and gaskets <NUM>, <NUM> relative to the extensions <NUM>, <NUM> and the metal plate <NUM> after installation, thereby preserving weather-tightness and extending the useful life of the glazing system. The reduction in the number of parts required to assemble the glazing system simplifies assembly and reduces the inventory storage and processing required for a system with a greater number of parts, as well as, the staging required in preparing for an installation.

Claim 1:
A pressure plate assembly (<NUM>) for holding at least one glazing unit (<NUM>, <NUM>) to a frame member (<NUM>), comprising:
(A) an elongated metal plate (<NUM>); and
(B) an elongated composite plate (<NUM>) formed from a material having a thermal conductivity less than the metal plate, the composite plate and the metal plate aligned and coupled together to form the pressure plate assembly, the pressure plate assembly configured to be fastened to the frame member with the composite plate proximate the frame member and the metal plate distal to the frame member, the pressure plate assembly configured to press at least one glazing unit toward the frame member,
wherein the composite plate has a pair of gaskets (<NUM>,<NUM>),
wherein the composite plate has a pair of ledges (<NUM>, <NUM>) extending along opposing side edges of the composite plate, the ledges embracing the metal plate therebetween, wherein each ledge has a land (16P, 18P) at a tip thereof extending toward the metal plate,
the pressure plate assembly being characterized in that each of the gaskets:
covers an outside surface (16Q, 18Q) of a corresponding one of the ledges;
surmounts an upper edge (16T, 18T) of the ledge; and
returns in a downward direction on an inside surface (16I, <NUM>) of the ledge,
wherein the gaskets form a seal between the metal plate and the lands.