AU5606299A - A cavity wall panel system - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 0o oo *e o*

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Applicant: A CAVITY WALL PANEL SYSTEM DIMITRIOS TRAMBAS The following statement is a full description of this invention, including the best method of performing it known to me: 1 VAT C:\WINWORD\VIOLET\CHRIS\ODELETEXPIPiCOMODOC A CAVITY WALL PANEL SYSTEM The present invention relates to a cavity wall panel system, particularly but not exclusively for the construction of insulated wall panels for refrigerated containers, such as refrigerated storage rooms and refrigerated vehicles.

Cavity wall panel systems are widely used in the construction of insulated wall panels, and consist essentially of an inner skin and an outer skin separated by a number of spacing brackets between which inner and outer skins an insulating 10 material is introduced to provide effective thermal insulation across the panel.

Typically the inner skin is made from sheet stainless steel as it may come into contact with wet or corrosive matter, whilst the outer skin may be made from standard carbon steel. The insulating material which fills the intervening cavity is typically an expandable foam polyurethane product injected between the inner 15 and outer skins once the latter have been fixed into their relative positions by means of the spacing brackets.

Typically the spacing brackets comprise double-flanged metallic structural members such as Z- or U- beam components. The opposed flanges of these 20 components are fixed respectively to the inner and outer skins by means of pop rivets. A disadvantage to this construction is that the pop riveting process results in the undesirable piercing of the inner and outer skins. It is possible as an initial fabrication stage to spot weld the spacing brackets to either the inner or the outer skin, but then it becomes impractical to spot weld the brackets to the other of the skins as the welding equipment must be introduced into the panel cavity, which is typically of a width of only a few centimetres. In any event, spot welding within the panel cavity does not readily lend the fabrication process to continuous production.

It is an aim of the present invention to provide a new cavity wall panel system which is simple to fabricate but which palliates the inconvenience of the prior art.

According to the invention there is provided a cavity wall panel system including: a first sheet component having at least one first securing bracket projecting therefrom; a second sheet component having at least one second securing bracket projecting therefrom; locking means; said at least one first securing bracket and said at least one second securing bracket being selectively mutually engagable by means of said locking means introduced therebetween when said first and second sheet components 10 are brought into adjacent relationship, thereby to restrain the subsequent *o separation of said first and second sheet components.

a In a preferred form, the locking means includes at least one rod-like locking element and said at least one first securing bracket and said at least one second 15 securing bracket include closed loop elements through which said at least one °rod-like locking element can be passed.

In one embodiment, said at least one first securing bracket and said at least one second securing bracket include a plurality of elongate elements of generally 20 undulating form. They may be of zig-zag, corrugated, fluted or other form. Said elongate elements may be approximately evenly spaced across said first and said second sheet components. Preferably additional ones of said elongate elements are provided towards the periphery of said first and said second sheet components.

The cavity wall panel system of the invention may include a material to be introduced between said first and said second sheet components once these latter have been brought into adjacent relationship.

According to a further aspect of the invention there is provided a container including wall panels constructed from the cavity wall panel system as described hereinbefore.

According to a yet further aspect of the invention there is provided a method for fabricating cavity wall panels including the steps of: providing a first sheet component having at least one first securing bracket projecting therefrom; providing a second sheet component having at least one second securing bracket projecting therefrom; bringing said first and said second sheet component into adjacent relationship; 10 introducing a locking means between said sheet components to selectively mutually engage said at least one first securing bracket and said at least one second securing bracket thereby to restrain the subsequent separation of said l* *l* first and second sheet components.

15 The invention will now be described by way of illustrative example with reference to the accompanying drawings, in which like reference numerals designate like features and in which: Fig. 1 shows the prior art and is a sectional view of a cavity wall panel of typical construction; 20 Fig. 2 shows a sectional view of a cavity wall panel system according to the S"present invention; and Fig. 3 shows diagramatically a side elevation of one panel component of the cavity wall panel system of Fig. 2.

Referring to Fig. 1 of the drawings, a conventional cavity wall construction comprises an inner skin 10 and an outer skin 20 mutually separated and connected by a number of spacing brackets 30. The inner skin 10 is made from rolled sheet stainless steel whilst the outer skin 20 is made from rolled sheet carbon steel. The spacing brackets 30 are formed from steel Z-beam members as shown, the opposed flanges of each member being respectively fixed to the inner and the outer skins by means of pop rivets The embodiment of the invention depicted in Fig. 2 comprises in similar manner an inner skin 10 and an outer skin 20. Two sets of pressed steel brackets 50; are associated respectively with the inner skin 10 and outer skin 20, each set of brackets consisting of a number of continuous strips of rolled steel of regular zigzag elongate form as shown. In fabrication, each strip 50; 60 is brought into contact with the appropriate skin 10;20 and fixed in place, ideally by spot welding, at the evenly spaced points of contact 51;61, the strips being arranged parallel to and spaced from one another (Fig. This results in two independent unitary panel components: an inner skin 10 with its associated set of brackets 50 and an 10 outer skin 20 with its associated set of brackets To construct the wall panel, the two skins 10;20 are brought together with the sets of brackets 50;60 orientated parallel to one another and such that each bracket of one set can be introduced into the space between the parallel brackets of 15 the other set. As can be seen from Fig. 2, the outermost projecting parts 52;62 of the two opposed sets of brackets 50;60 can therefore interdigitate, the closest separation of the steel skins 10;20 thus being determined by the distance between the outmost projecting parts 52;62 of each set of brackets and the skin 10;20 to which it is fixed.

To mutually secure the two panel components elongate cylindrical securing bars are then introduced into the longitudinal spaces provided by the overlap of the interdigitating outermost projecting parts 52;62 of the two sets of brackets 50;60 as shown in Fig. 2. This prevents the subsequent separation of the two panel components, the furthest possible separation of the steel skins 10;20 then being determined by the diameter of the securing bars 70. The securing bars 70 are preferably made of nylon material, but may be made from any material with suitable mechanical properties.

The final step of fabricating the cavity wall panel is the introduction of an expandable foam polyurethane cavity filler product into the cavity 80 between the skins 10;20.

6 The drawing of Fig. 3 shows the inner panel component, comprising the inner skin and its set of parallel steel brackets 50 illustrated in side elevation. The positions of the counterpart steel brackets 60, fixed to outer skin 20, are depicted by broken lines. In the particular panel design shown a set of two closely-spaced brackets are provided close to the upper edge of the panel at 85mm separation, the remaining brackets being mutually spaced by approximately 300mm.

Similarly the opposed outer panel component features two closely-spaced brackets close to the lower edge of the panel at 85mm separation, the remaining S 10 brackets being mutually spaced by approximately 300mm. The construction illustrated has brackets of about 30mm width, spot welded to the skin at 192mm centers (the repeating linear distance of the zig-zag form). Neighbouring nylon securing bars are therefore separated by 192mm. The securing bars are of circular section of 12mm diameter. In securing together the two panel 15 components full length nylon bars 701 are threaded through the sets of opposed brackets adjacent the panel edges to secure the lateral edges, whilst shorter nylon bars 702 are threaded through the first three brackets 50;60 as shown to secure the upper and lower edges of the panel.

20 The closer spacing of the steel brackets 50;60 and the presence of the full length l nylon bars 701 give particular rigidity to the panel around its periphery. However, it is evident that the spacing of the brackets may be uniform and/or full length nylon bars may be introduced through the brackets across the width of the panel.

The design and spacing of the brackets as well as the arrangement, length and spacing of the nylon bars may be selected depending on the particular application envisaged for the resulting panel.

Many modifications to the construction described may be envisaged. The invention has been described and illustrated with reference to a double-walled cavity wall panel, but clearly a multiple layer panel may be envisaged with internal skins being provided with sets of brackets on both sides and securing bars being introduced in each of the plurality of resulting cavities.

Depending on the application the orientation of the sets of brackets may be vertical, horizontal or otherwise. The steel skins need not be planar but may be curved or corrugated. Both the brackets and the securing bars may be of any suitable cross section and may be perforated if desired in order to reduce weight and more readily allow the flow of insulating material introduced between the skins. The brackets have been described above as of zig-zag elongate form, but may be of any other form which affords the alternating arrangement of parts of the brackets when the two skins are brought together, in order to permit the introduction of the securing rods to restrain the skins from subsequent separation.

S. 10 For example, the brackets may be of an elongate undulating form, such as corrugated or fluted, or may be formed of a series of individual projecting V- or U- O shaped elements. Many alternative configurations may be contemplated.

It is to be noted that in addition to affording the mutual restraint of the two skins 15 the brackets serve to provide more effective stiffening reinforcement to the steel skins to which they are fixed than would be available in a conventional cavity wall panel.

OV 0.: It is understood that various modifications, alterations and/or additions may be 20 made to the embodiments specifically described and illustrated herein without departing from the spirit and scope of the invention.

Claims (8)

1. A cavity wall panel system including: a first sheet component having at least one first securing bracket projecting therefrom; a second sheet component having at least one second securing bracket projecting therefrom; locking means; said at least one first securing bracket and said at least one second securing bracket being selectively mutually engagable by means of said locking 10 means introduced therebetween when said first and second sheet components *are brought into adjacent relationship, thereby to restrain the subsequent separation of said first and second sheet components.

2. A cavity wall panel system according to claim 1, said locking means 15 including at least one rod-like locking element and said at least one first securing bracket and said at least one second securing bracket including closed loop elements through which said at least one rod-like locking element can be passed.

3. A cavity wall panel system according to claim 2, wherein said at least one 20 first securing bracket and said at least one second securing bracket include a plurality of elongate elements of generally undulating form, such as zig-zag, corrugated or fluted form.

4. A cavity wall panel system according to claim 3, wherein said elongate elements are approximately evenly spaced across said first and said second sheet components.

A cavity wall panel system according to claim 3 or claim 4, wherein additional ones of said elongate elements are provided towards the periphery of said first and said second sheet components.

6. A cavity wall panel system according to any preceding claim, including a material to be introduced between said first and said second sheet components once these latter have been brought into adjacent relationship.

7. A container including wall panels constructed from the cavity wall panel system according to any preceding claim.

8. A method for fabricating cavity wall panels including the steps of: providing a first sheet component having at least one first securing bracket 10 projecting therefrom; :.::-providing a second sheet component having at least one second securing bracket projecting therefrom; bringing said first and said second sheet component into adjacent relationship; 15 introducing a locking means between said sheet components to selectively mutually engage said at least one first securing bracket and said at least one second securing bracket thereby to restrain the subsequent separation of said Get* e: first and second sheet components. S0 DATED: 25 October, 1999 PHILLIPS ORMONDE FITZPATRICK Attorneys for: DIMITRIOS TRAMBAS