1. Field of the Invention
The present invention relates to glazed structures and more particularly to glazed structures using semi-rigid plastic panels as the glazing material.
2. Description of the Prior Art
Semi-rigid plastic panels, particularly of polycarbonate, are widely used as a glazing material in building structures such as roofs and walls. It is relatively lightweight and is quite versatile in that it is able to accommodate a degree of bending and can therefore be incorporated into a curved roof or curved wall. One common method of securing the panels is by screwing directly to underlying support structure usually by means of self-drilling screws which incorporate a sealing washer to prevent water penetration at the point of penetration of the screw through the panel. However systems which do not require penetration of the panel are to be preferred. One such system which avoids the need for penetration by individual self-drilling screws and which permits significantly faster installation, uses plastic panels with an upstanding lip extending along each of its two longitudinal edges. The adjacent lips of two adjacent panels are fastened together by a connector channel which is a snap-fit over the two lips. A system of this type which is now extensively used in Australia and many other countries is sold under the trade mark DANPALON of Dan-Pal, Upper Galilee, Israel. The DANPALON system principally uses multi-cell polycarbonate panels having a core formed by three or more layers of elongate cells running the length of the panel or alternatively the panel may be solid sheet of appropriate thickness, for example 4 mm.
In the existing DANPALON system, the glazing panels are secured to underlying support structure, such as purlins, extending widthwise of the panels by brackets which are screwed to the structure and which interfit with the upstanding lips of adjacent panels. When the connector channel is applied to the two lips, the channel also retains the lips against the brackets to thereby ensure that the panels are securely fastened at that point to the underlying structure. Accordingly a very secure and watertight fastening can be achieved without penetration of the panels and without the use of applied sealants or adhesives.
While the system described above is an effective system, when used on large roof spans for example (typically those in excess of 4 metres), a significant under-structure is required to provide adequate structural support. This not only adds to the expense of the structure but may also adversely affect its aesthetics.
Moreover, although the fastening system using the connecting channels does facilitate installation while providing a watertight connection between the adjacent panels, nevertheless the brackets by which the panels are held to the underlying support structure are required to be individually attached to the structure by being screwed to the structure and this in itself can be a relatively time consuming exercise.
According to the present invention there is provided a glazed structure comprising glazing panels arranged side-by-side with adjacent longitudinal edges of pairs of adjacent panels being supported by a bar common to both panels and extending lengthwise of the two edges, each of the adjacent edges having an upstanding lip and the bar including an integral T-section extension from a panel-support surface of the bar, with the upstanding lips of the two panels lying between the support surface and the transverse flange of the T-section extension at respective sides of the central flange of the T-section extension, and a connector applied over the projecting lips to hold the lips captive within the T-section extension and thereby to secure the longitudinal edges of the panels to the bar.
Further according to the invention there is provided a glazed structure comprising semi-rigid glazing panels of plastic material arranged within the structure with longitudinal edges of pairs of adjacent panels in side-by-side relation and each longitudinal edge including an integral upstanding lip, each pair of adjacent panels within the structure being supported at their adjacent longitudinal edges by an outwardly facing surface of a longitudinally-extending support bar whereby the two adjacent edges of the two panels are supported by that bar along their entire length, the bar including a retaining flange parallel to the said surface of the bar but spaced outwardly therefrom with the two lips being located between the retaining flange and said surface, and a connector channel applied over the retaining flange and the outer sides of the two lips to retain the lips between the retaining flange and the said surface of the bar and thereby securing the edges of the two adjacent panels to the bar.
Still further according to the invention there is provided a glazed structure comprising bars which provide structural support arranged in parallel relation, semi-rigid glazing panels arranged within the structure with longitudinal edges of pairs of adjacent panels being supported by a said bar which is common to both panels and which extends lengthwise of the two panels, each of the adjacent edges having an upstanding lip and the bar including an integral T-section extension from a panel-support surface of the bar, with the upstanding lips of the two panels lying between the support surface and the transverse flange of the T-section extension at respective sides of the central flange of the T-section extension, and a connector applied over the projecting lips to hold the lips captive within the T-section extension and thereby to secure the longitudinal edges of the panels to the bar.
Still further according to the invention, there is provided a bar intended for use in a glazing system as defined above, the bar having a portion of hollow section with an outer surface providing a panel-support surface of the bar and a T-section extension projecting from the surface to act in conjunction with a connector to retain the lips of the panels, the portion of hollow section and the extension being integrally formed as an extrusion.
An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings in which:
The system of the preferred embodiment of the invention is based on the DANPALON system and, indeed, is able to use the panels and connector channels of the DANPALON system but uses a different form of underlying support which both enables larger spans to be achieved without the need for additional underlying support structure and also avoids the need for individual brackets for securing the panels. It is however to be understood that the invention is not confined in scope to the use of DANPALON panels and connectors. Accordingly the invention is suitable for use with other glazing panels having upstanding lips along their longitudinal edges for co-operation with connectors which fit over the two adjacent lips of two adjacent panels.
In the system of the invention, each pair of adjacent panels 2 is supported along the entire length of their adjacent longitudinal edges by a support bar 10 which extends longitudinally of the panels 2. The bar 10 is profiled to enable it to traverse a large span without the need for underlying support structure along its length. This is achieved by forming the main structure of the bar as a hollow section 12 reinforced along its outer side (the side to which the glazing panels 2 are applied) by an integral extension 14 of T-section. It will be understood that this T-section extension 14 acts in conjunction with the outer side of the hollow section 12 substantially in the manner of an I-beam to provide substantial reinforcement against bending deflection of the bar 10 under the applied loading of the glazing panels. In the particular form shown, the hollow section 12 of the bar 10 is tubular, specifically rectangular, although other sections which provide the required strength against deflection and which have a substantially planar outer surface against which the edges of the two panels 2 will rest, can be used. The bar 10 can readily be formed by extrusion, for example in aluminium or other suitable alloy or metal and the extruded bar can be roll-formed to a required curvature if it is to be used within a curved arched roof structure as illustrated by way of example in
The T-section extension 14 in addition to strengthening the bar 10 to provide a greater span length, also acts as the means for securing the panels 2 to the bar without the need for additional brackets. For this purpose, the spacing between the outer transverse flange 14a of the extension 14 and the outer face of the hollow section 12 corresponds to the depth of the upstanding lip 4 along the longitudinal edge of the panel so that the lip 4 can fit beneath, and be held captive by, the underside of the flange 14a. It is however to be noted that the upstanding lip 4 is not a tight fit under the flange 14a but instead a small gap is left, possibly of the order of 1 to 2 mm, to allow for thermal expansion of the plastic panel under elevated temperatures. The lateral projection of the transverse flange 14a to each side of the central flange 14b of the extension 14 also corresponds approximately to the width of the lip 4.
When the connector channel 6 is applied over the two adjacent lips 4 which abut against the opposite sides of the central flange 14b, the ribs 6a along the sides of the connector channel 6 will snap-lock with the ribs 4a on the lips 4 to ensure that the lips 4 are anchored to the extension 14 and hence are positively locked to the bar 10. This is the condition shown in
In a practical form of the preferred embodiment in which the bar 10 is designed for use with DANPALON multi-cell panels whereby the lateral projection of the transverse flange 14a corresponds to the width of the upstanding lips 4 on those panels, the bar 10 is also suitable for use with DANPALON panels of solid structure in which the lips are thinner than those of the multi-cell panels. This is achieved by the use of L-section insert strips 16 laid along the outer side of the bar 10, as shown in
Further components of the system are illustrated in
The panels 2 with the integral upstanding lips 4 may be produced in a number of standard widths which are cut to required length for use. Although it is desirable to design the structure so that each section of the structure can accommodate a complete panel of standard width, in some situations an end section of the structure may be of a width less than a standard width. In that case the glazing panel for use in that section can be cut to the required width leaving a small excess portion which can be manually bent upwardly to form a projecting lip by partially cutting through the thickness of the panel to facilitate bending. That lip can then be secured to the extension 14 of the end-most bar 10 in the structure using the connector channel as previously described.
As mention previously, although the preferred embodiment is particularly suitable for use with existing DANPALON panels, which are polycarbonate panels and connector channels, the embodiment is not confined specifically to use with those panels and the associated connector channels. Other glazing panels formed from polycarbonate sheeting or other suitable plastic sheeting and having upstanding lips along their longitudinal edges may alternatively be used; likewise other forms of connector which fit over the lips to secure the lips to the bar to provide a watertight seal can be used.
It will be understood that the system in accordance with the invention in addition to permitting increased roof spans without the need for intermediate underlying support structure, also obviates the need for the incorporation of individual brackets to secure the panels to the structure as the function of the brackets is now fulfilled by the T-section extension which forms an integral part of each support bar. Accordingly installation time and costs are significantly reduced.
Although the preferred embodiments have been described principally in relation to roof structures, it is to be understood the invention in its preferred embodiments is applicable to other structures such as wall structures. Although the structure can have curvature achieved by bending the support bars, the structure can be substantially planar in form.
The embodiment has been described by way of example only and modifications are possible within the scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
2005201266 | Mar 2005 | AU | national |