JOINING SHEET METAL PRODUCTS

FIELD OF THE INVENTION

The invention relates to a product made from sheet metal, a method for forming a product made of sheet metal and a method for joining products made of sheet metal together. The invention finds particular but not exclusive application in joining building elements and/or building components formed of sheet steel together and, for instance, has use in the fabrication and/or erection of metal framed buildings, wall frames and partitions, roof trusses, and metal panels and sheets,

BACKGROUND OF THE INVENTION

Metal framed buildings and dwellings have been known in the art for some time.

The wall frames of such structures typically comprise spaced apart upright studs extending between horizontal roof and floor structural members, and substantially horizontal noggings disposed between adjacent ones of the studs. The wall frames support metal roof trusses forming the τoof structure of the building or dwelling, and the studs, Hoggings and trusses are often fabricated by roll-forming steel strip. Buildings of this type are commonly roofed and cladded with metal panels and sheets having a ribbed cross-section providing structural support to the panels and sheets. The metal panels and sheets are typically fastened to the wall studs and roof trusses by self-tapping screws. Clinch joints have been used in the past to fasten overlapping metal sheets and in the fabrication of frame elements for use in the construction of the frame of such buildings and dwellings. Conventionally, the clinches are formed by a co-operating male punch and female die. the punch plasticly deforming the sheet metal forward of the punch into the die cavity and laterally swaging the displaced metal such that mechanical inter-engagement of the overlapping metal sheets i$ effected thereby holding the sheets together.

Various clinching apparatus with co-operating punches and dies are known in the art including apparatus which utilise a rotary punch and die set. Such clinching apparatus arc adapted to form a row of spaced apart clinches along the overlapping metal sheets, in use, the clinches are formed by driving the clinching tool along the metal sheets or by feeding the $heets between the rotary punch and die $et. An example of a clinching apparatus is described in International Patent Application No. PCT/AU91/00120, The formation of the clinches in the required location requires careful alignment of both the clinching apparatus and the overlapping sheet metal work pieces, and support of the work pieces during the clinching process. This is particularly the case when a row of clinches along the overlapping metal sheets is formed. Further examples of clinching dies and types of clinch joins are described in Australian Patent No. 675590 and Australian Patent Application No, 50457/93.

SUMMARY OJF THE INVENTION

Broadly stated, the present invention relates to pre-formiπg connection sites in a. product made of sheet metal for alignment and subsequent forming of joins with corresponding connection sites formed in one or more other products made of sheet metal. In one aspect of the invention there is provided a product made from sheet metal, such as sheet steel, the product having opposite races and one or more than one connection site comprising a section displaced from the plane of the sheet forming a protrusion in one of its faces and a recess in the other face, the protrusion being adapted to form a join with a corresponding connection site provided on another product to fasten the products together upon the connection sites being driven together deforming the protrusion in a recess of the connection site of the other product. in another aspect of (he invention there is provided a method for forming a product made from sheet metal, such as sheet steel, the product having opposite faces and one or more than one connection site, which method includes displacing one or more than one section of the sheet from the plane of the sheet forming a protrusion of the connection site in one of its races and a recess in the other face, the protrusion being adapted to form a join with a corresponding connection site provided on another product

to fasten the products together upon the connection sites being driven together deforming the protrusion in a recess of the connection site of the other product.

The method can further comprise forming spaced apart slits in the sheet disposed alongside relative to one another, and displacing the section of the sheet metal between the slits out of the plane of the sheet to provide respective of the protrusions. In at least one embodiment, a pair of slits that are substantially parallel with respect to each other arc formed in the sheet. Alternatively, the slits can be formed in the sheet as the interposed section of the sheet is displaced during the formation of the protrusion.

Moreover, in one or more embodiments, the displaced section is in the form of a button.

In another aspect, there is provided a method for joining together two products made from sheet metal, such as sheet steel, the products having one or more than one connection site comprising a section displaced from the plane of the sheet, and the method comprising: (a) positioning the products together so that the connection sites on each sheet are aligned and ne$t one in another; and

(b) driving respective of the nested connection sites together deforming one of the displaced sections within the other to form at least one join.

The method is particularly suitable for joining products in the form of building elements together.

Hence, in another aspect of the invention there is provided a method for fastening a product in the form of a building element made of sheet metal to at least one other building element made of sheet metal, each building element having opposite faces, and the method comprising: providing the product, the product having one or more connection sites comprising a section displaced from the plane of the sheet forming at least one protrusion projecting from one of its faces and a recess in the other face, the protrusions being located for alignment with otic or more recesses of respective connection sites provided in an opposite face of the other element, and the connection sites being adapted to form at least one join with the connection sites of the other element to fasten the elements together;

aligning respective of the connection sites of the product and the other element together such that the protrusions nest in the recesses of the other element; and driving the aligned connection sites together deforming the nested protrusions in the recesses of the other element to form the at least one join. The one or more connection sites of the fir$t building element can be provided along at least one zone of the first element The at least one zone can be an outer edge margin alongside one edge of the element, a middle zone, and/or or an opposite outer edge margin alongside an opposite edge of the element,

Respective of the zones of the building element can have a plurality of the connection sites spaced apart from one another therealong.

In at least some embodiments, the product is fastened to a plurality of other building elements, and each zone of the product is fastened by one of the connection sites to one of the other elements, respectively. Typically, the zones of the product comprise opposite edge margins of the product, In another aspect of the invention there is provided a method for fabricating a product in the form of a building element made of sheet metal for being fastened to at least one other building element made of sheet metal in the erection of a building structure, the product having opposite faces, and the method comprising forming in the sheet metal at least one connection site comprising a section displaced from the plane of the sheet providing a protrusion projecting from one of its faces and a recess in the other face, the protrusion being provided in a pre-determined location for alignment with a respective recess of a connection site in an opposite race of the other element, and the protrusion being adapted to nest in the recess of the other element when the connection sites are in alignment and to form a join fastening the product and the other element together upon the nested protrusion being deformed when the aligned connection sites are driven together.

In still another aspect of the present invention there is provided a product in the form of a building element made of sheet metal for being fastened to at least one other building element made of sheet metal in the erection of a building structure, the product having opposite faces and at lea$t one connection site comprising a section displaced from the plane of the sheet forming a protrusion projecting from one of its faces and a recess in the other face, the protrusion being provided in a pre-determined location for

alignment with a respective recess of a corresponding connection site in an opposite said face of the other element, and the protrusion being adapted to nest in the recess of the other element when the connection sites are in alignment and to form a join fastening the product and. the other element together upon the nested protrusion being deformed when the aligned connection sites are driven together.

The product can have a roll-formed cross-sectional profile. The connection sites can be formed in the product before, during or after the roll forming of the product. In at least some embodiments, the product is passed through the nip of a rotary punch and die set forming at least one row of the connection sites along the product. The product can, for instance, be a metal panel, sheet, bracket, support member, studj frame element, roof truss element or any other component made from sheet steel in a building structure. The other building element(s) can be a further a metal panel, sheet, bracket, support member, stud, frame element, roof truss element or any other component of the building structure that is made of sheet steel. Tn at lea$t some embodiments the product is a metal panel or sheet and the other element(s) is a frame element(s) of the building structure. The frame elemetit(s) to which the metal panel or sheet is fastened by respective of the connection sites can be in position in the wall frame of the building structure prior to the metal panel being fastened to the frame by respective of the connection sites. The frame can be completed or only partiall y erected.

Accordingly, in another aspect of the invention there is provided a method for roofing or cladding a metal frame of a building structure, comprising: providing at least one metal sheet or panel made from sheet material having opposite side faces and one or more connection sites comprising a section displaced from the plane of the sheet forming a protrusion projecting from one of its feces and a recess in the other face, the protrusion being provided in a predetermined location for alignment with a respective recess of a corresponding connection site formed in an Opposite face of at least one frame element of the metal frame, the frame element being made of sheet metal; aligning respective of the connection sites of the panel with the connection sites of (he frame element such that the protrusions nest in the recesses of the frame element; and

driving the aligned connection sites together deforming the nested protrusions to form at least one join, fastening the panel to the frame element.

The join can be any type of join formed by deformation of a protrusion in the recess of the corresponding connection site of the other building element, In at least some embodiments, the join is a clinch join. The deformation of the protrusion can be achieved by punching the protrusion using a hand held punch. An anvil can also be placed behind the other product to facilitate deformation of the protrusion. The anvil can be any tool or implement suitable for the purpose. In addition, the join may be formed without shearing of the periphery of the protrusion although in some embodiments, the periphery of the protrusion will be sheared as the protrusion is deformed.

The building structure can, for instance, be a dwelling, warehouse, shed, barn, workshop, factory or other type of building structure such as a fence or partition wall. Advantageously, one or more embodiments allow products in the form of building elements to be fastened together during the erection of the building structure. The building elements can be fastened together solely by respective of the joins. However, supplementary fastening means can also be employed. For instance, a suitable adhesive can be used in the join to assist in fastening the elements together following the formation of the joins. Alternatively, or as well, a fastener can be driven through respective of the joins to further secure the elements to one another. It is a further advantage that in one or more embodiments, the pre-formed connection sites assist in correct alignment of the elements relative to each other. The nesting of the connection sites also assists in retaining the elements together pending formation of the joins. This may allow for ease of roofing or cladding metal framed building structures and in the erection of wall frames, roof trusses, partition walls and the like which can result in time and thereby cost savings. The joins may, therefore, be formed without the need for highly skilled workers or specialized equipment.

All publications mentioned in the specification are herein incorporated by reference. Any discussion of documents, acts, materials, devices, articles or the like which has been included in this specification is solely for the purpose of providing a context for the invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field

relevant to the invention as it existed in Australia or elsewhere before the priority date of this application.

Throughout this specification the word "comprise", or variations thereof Such as "comprises" or "compiling", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The features and advantages of the invention will become further apparent from the following detailed description of non-limiting embodiments.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Figure IA and IB show schematic cross-sectional views of aligned connection sites in overlapping products made of metal sheet before and after the formation of a join fastening the products together; Figures 2 A and 2B are schematic cross-sectional views of further embodiments of aligned connection sites in overlapping metal sheets before and after the formation of a join fastening the products together;

Figures 3A and 3B are schematic cross-sectional views of still further embodiments of aligned connection sites in overlapping metal products before and after the formation of a join fastening the sheets together; and

Figures 4A to 4C are schematic plan views illustrating alternative possible shapes of the protrusions of connection sites of the upper product of Fig. 3A.

DETAILED DESCRIPTION OF EMBODIMENTS OF TME INVENTION

The invention is further described below by reference to products made from sheet metal, a method of forming a product made from sheet metal and a method of joining such a product to another product made of sheet metal and in particular, to fastening a product in the form of a sheet steel panel to another product being a steel frame element of the metal frame of a building structure, Tn the present embodiments, the frame elements are upright wall studs of the metal frame Of the building structure. The building structure for present purposes is a warehouse although it will also be

understood the building structure could for instance be a shed, factory, fence or the like as described above.

The metal panel has opposite $ide margins each of which is provided with a row of spaced apart connection sites comprising deformations formed by sections displaced from the plane of the panel for forming clinch joins with a row of corresponding connection sites provided on the wall stud. Each of the wall studs comprises opposite longitudinal flanges connected together by a web portion which is generally typical of such sheet metal studs.

As indicated in Fig. IA, the connection sites of the metal panel and wall stud each comprise a protrusion in one face and a recess in the opposite face thereof, formed by displacing a section of the panel from the plane of the panel. The protrusions of the metal panel 2 are indicated by the numeral 4 and are initially aligned with respective of the recesses 6 ^" of the wall studs 8 such that the protrusions and recesses of the panel and studs nest one in the other. A hand held punching tool is then used to punch the respective protrusions of the panel into the recesses of the wall studs to form clinch joins fastening the panel to the studs as generally illustrated in Fig. 1 B. As illustrated, the protrusions and recesses of each the panel and stud have substantially complementary cross-sectional profiles. Under the driving action of the punch, the periphery of the protrusions is sheared effecting inter-engagement of the panel and wall stud building elements fastening them together. The punch can be any suitable tool adapted for insertion into the recess 10 of protrusions 4 for forming the clinch joins upon an impact force being applied to the punch by a hammer.

Alternative possible forms of the connection sites are illustrated in Figs. 2A and 2B. As will also be understood, in this embodiment the connection sites of the panel and wall stud include mating dimples 12 and 14 each provided by displacing a section of the respective metal sheet from the plane of the sheet whereby a slit in the sheet is formed either side of the dimple. In use, the dimples 12 and 14 are driven outwardly under the action of the punch 16 and are each flattened, swaging the displaced metal laterally to form the clinch join (see Fig. 2B). It will be understood that in ihi$ embodiment, each protrusion 12 of the panel 2 is nested in the recess of a corresponding connection site of the wall $tud a$ described above, the dimples being defined in the protrusion of the panel and the floor of the recess of the wall stud _> respectively.

Further alternative forms of connection sites are illustrated in Figs. 3 A and 3B. In this instance, respective of the protrusions 4 comprise a raised button \ 8 received in the recess of a corresponding connection site provided in the wall studs 8. Punching the buttons 18 again flattens the buttons, swaging the displaced metal laterally into inter- 5 engagement with the studs fastening the panel to the studs. Different possible profiles for buttons 18 are illustrated in Figs. 4A to 4B. The shaded regions in Figs. 4A and 4C indicate lateral movement of the displaced metal effecting the inter-engagement of the panel with the stud when the buttons are punched.

Typically, each wall stud will be provided with two adjacent rows of recesses 6

\ 0 therøalong, One row being provided for fastening one of the edge margins of one panel 2 to the stud and the other row for fastening an opposite edge margin of an adjacent panel 2 to the stud. The rows of recesses 6 are sufficiently spaced apart from each other on (he stud to permit overlapping of the edge margins of the adjacent panels 2 and thereby cladding of the wall frame of the building structure. If necessary, further rows of metal

15 panels 2 can be fastened one above another to the wall studs of the metal frame as necessary to complete the cladding of building structure.

In some embodiments, the formation of the clinch joins will be sufficient to fixedly secure the metal panels to the frame. In other embodiments, a suitable adhesive can be used in the joins to assist in fastening the panels and studs together following 0 formation of the clinch joins. In addition, once the clinch joins have been formed, fasteners in the form of self-tapping screws or the like can be driven through the clinch joins to further secure the panels and wall studs together. In this instance, adhesive may or may not be used in the join. Moreover, at least some forms of the protrusions of the panels 2 can be provided with centrally located holes 22 through which the screws are 5 driven into the wall studs 8 (see Figs. 4A and 4B).

While protrusions and recesses 4 and 6 having a number of different profiles have been exemplified, it will be understood the protrusions can have any suitable profile for forming a clinch join in accordance with invention. Similarly, the roof frame of the building structure can be roofed with metal sheets in the same manner. In this 0 instance, the roof trusses of the roof frame are provided with pre-formed recesses for forming clinch joins with the protrusions of the metal sheeting.

The roof trusses and wall studs of the building structure will typically have a galvanised coating and the steel sheets used for cladding and/or roofing the building structure will generally have a thickness of between 0.85 mm and 1.2 mm. The sheets will also normally have a galvanised or zinc and aluminium alloy coating for protection against corrosion, and can have an outer paint finish.

Ia some applications, a further row of connection sites can be formed along a central zone of the metal $heet$ in addition to the outer zones defining the outer edge margins of the sheets for the formation of clinch joins with a corresponding roof truss or wall stud in the situation where the metal sheet is to be fastened to three consecutive wall studs or roof trusses. In this instance, the roof trusses or wall studs will be provided with a central further row of connection $ite$ located for alignment with the connection sites provided in the central zone of the metal sheet.

The connection sites can be pre-formed in the wall studs and metal sheets using any suitable method for subsequent alignment of the metal sheets with the wall studs for formation of the clinch joins. In at least some forms, the connection sites will be formed by feeding galvanised sheet steel through the nip of one or more rotary punch and die sets to form the required rows of the connection sites. The formation of the connection sites can involve forming slits either side of the section to be displaced from the plane of the sheet metal to facilitate formation of the protrusion in the sheet. Generally, the slits will be substantially parallel with respect to one another. The slits can be formed in the sheet metal prior to the displacement of the section between the slits or as the displacement of the section occurs.

Although methods embodied by the invention find particular application in the roofing or cladding of metal framed building structures, the invention is not limited thereto. For instance, the metal panels and sheets 2 can be fastened together by aligning pre-formed connection sites provided in each of the panels or sheets, and punching the nested connection sites together to form clinch joints as described above. Similarly, this method of fastening can be used to fasten one frame element of the metal frame of the building structure to another frame element. For example, a noggin g with opposite end flanges provided with protrusions as described above can be fastened in position between adjacent wall studs 4 in this way, the protrusions of the Hogging being located

for alignment with corresponding recesses of connection sites provided on the wall studs.

Moreover, nested protrusions of the sheet metal building elements can be driven together with the use of pliers or other like hand tool, or with the use of a clinching tool adapted for the purpose. An anvil can also be pressed behind the element receiving the protrusion to provide a reaction force to a punch impact. The anvil can be a pair of pliers, the side or face of the head of a hammer, or any other suitable tool or implement.

Accordingly, while a number of embodiments have been described, it will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention without departing from the spirit or scope of the invention as broadly described. The present embodiments arc, therefore, to be considered in all respects as illustrative and not restrictive.