AU2006200327A1 - Connector for Structural Members - Google Patents

Description

P/00/011 28/5/91 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Actual Inventor Address for service is: Formsteel Pty Ltd Martin Charles Holland WRAY ASSOCIATES Level 4, The Quadrant 1 William Street Perth, WA 6000 Attorney code: WR Invention Title: "Connector for Structural Members" The following statement is a full description of this invention, including the best method of performing it known to me:- -2- "Connector for Structural Members" Field of the Invention This invention relates to a connector for structural members, and more particularly to a connector for joining structural members at least one of which comprises timber.

The connector according to the invention has been devised particularly, although not necessarily solely, for use in the construction of trusses, and more particularly prefabricated trusses.

Background Art Traditionally, fabricated trusses comprise truss members which are either entirely timber or entirely metal.

With timber trusses, gang nail plates can be used for joining the timber truss members together. Typically, a gang nail plate comprises a metal plate with rows of sharp points that are driven into the timber truss members to secure them together.

Typically, a timber truss is prefabricated on a jig at which the various truss members are placed in position and then pinned together. Gang nail plates are then installed at joints between the truss members from one side of the truss.

The truss is then turned over and gang nail plates installed at the joints from the other side of the truss.

It is against this background that the present invention has been developed.

Disclosure of the Invention According to a first aspect of the invention there is provided a connector for joining structural members at least one of which comprises timber, the connector -3comprising a metal plate having a portion thereof presenting a plurality of points projecting from one face of the plate and a further portion thereof without points to which a further structural member can be fixed.

In such applications, the further structural member may comprise timber or metal.

Fixing of the further structural member to the further portion of the plate can be performed in any appropriate way. The further structural member may, for example, be mechanically fixed such as by nails or screws. In certain other applications, where the further structural member comprises metal, it can be fixed by a bonding process such as welding.

According to a second aspect of the invention there is provided a truss constructed using a connector according to the first aspect of the invention.

According to a third aspect of the invention there is provided a truss comprising a timber chord, a metal web, and a connector for joining the web and chord, the connector comprising a metal plate having a first portion presenting a plurality of points which project from one face thereof and which are driven into the timber chord, the metal plate having a second portion without points to which the metal web is fixed.

In one arrangement, the metal web is fixed to the metal plate by being bonded thereto such as by welding.

In another arrangement, the metal web is fixed to the metal plate by at least one mechanical fixing such as a nail or screw.

The metal web preferably has an end thereof configured for fixing to the metal plate.

Where, for example, the metal web is of tubular construction, the end of the tubular web can be deformed to provide a tab for attachment to the metal plate.

The tab may be aligned with the central longitudinal axis of the chord.

Alternatively, the tab can be offset laterally from the central longitudinal axis of the chord. The lateral offsetting can be such that the tab is aligned with a longitudinal edge of the chord.

In an alternative arrangement, the web may comprise a channel having two side portions and a bridge portion extending therebetween. In such a case, the channel may be notched at one end thereof by removal of a section of the bridge portion to provide a recess in which the chord can be accommodated, with sides of the notch in the channel located to the sides of the chord, and at least one notch side being joined to the chord through the connector.

The present invention further provides an automated system for cutting members of a truss and applying one or more connectors to the members, the automated system comprising a feed path, along which lengths of timber are conveyed in their longitudinal direction, the feed path incorporating an in-feed table, a measuring station, a first cutting station, a plating station, a second cutting station and a kick-off table.

Preferably the feed path comprises a continuous conveyor belt for carrying the lengths of timber in end to end relationship without any gaps therebetween.

Preferably the measuring station comprises a measuring wheel in rolling engagement with the timber being conveyed along the feed path for measuring lengths thereof and providing such information as necessary to the cutting and plating stations.

Preferably the first cutting station cuts the timber into prescribed lengths in addition to cutting any required notches.

Preferably the plating station includes a plating machine for applying one or more nail connectors to the cut timber.

The present invention further provides a plating machine for manufacturing a connector as herein before described.

The plating machine may comprise: at least one plating mechanism which feeds a strip of material to a stamping device, the stamping device punching apertures into prescribed portions of the strip to form a plurality of sharp points protruding from one face of the strip; a cutter into which the stamped strip is fed, wherein the cutter cuts the strip as necessary to form the required connector; an application location at which the connector is presented to a timber component with its points in contact therewith; and a press whereby the connector is driven into the timber such that its points are embedded therein.

There may be two plating mechanisms located on opposed sides of the timber feed path Preferably the strip material is supplied from a coil from which metal is unwound.

Preferably the timber is fed through the plating station under the driving influence of drive wheels disposed at intervals along the feeding length of the plating station.

The plating machine may further comprise a measuring wheel arrangement for measuring linear movement of the timber through the plating station.

The present invention further provides a method of manufacturing and applying one or more connectors to a structural member comprising the steps of: -6passing a length of timber along a feed path to a measuring station through which a prescribed length of timber is passed to a first cutting station; cutting the timber to form the prescribed length; forming a connector with the prescribed projections, and aligning the connector adjacent the timber at the desired location; passing the timber and connector through a press whereby the press causes the projections of the connector to be embedded in the timber such that the connector is secured to the timber.

Brief Description of the Drawings The invention will be better understood by reference to the following description of two specific embodiments thereof, preceded by a brief description of a conventional gang nail plate. The descriptions will be made with reference to the accompanying drawings in which: Figure 1 is a schematic view of a conventional (prior art) gang nail plate; Figure 2 is a schematic view of a connector according to a first embodiment; Figure 3 is a schematic view of a connector according to a second embodiment; Figure 4 is a schematic side view of a truss assembly constructed using connectors according to the first and second embodiments; Figure 5 is a fragmentary view of a part of the truss of Figure 4, showing a joint between two chords; -7- Figure 6 is a fragmentary view of a further part of the truss of Figure 4, showing a joint between a chord and two webs; Figures 7 to 10 inclusive illustrate various cross-sectional shapes of steel webs which can be employed in the construction of the truss of Figure 4; Figure 11 is a fragmentary schematic view illustrating a joint between a steel web of channel section and a timber chord; Figures 12 and 13 illustrate two cross-sectional shapes of tubular steel webs; Figure 14 is a fragmentary schematic view illustrating one type of joint between a steel tubular web and a timber chord; Figure 15 is a fragmentary schematic view illustrating another type of joint between a steel tubular web and a timber chord; Figures 16 to 20 are various schematic views illustrating truss joints which can be constructed utilising connectors according to the invention; Figure 21 is a schematic view of a system for automated production of trusses utilising connectors according to the invention; and Figure 22 is a schematic view of a plating machine forming part of the system illustrated in Figure 21.

Best Mode(s) for Carrying Out the Invention In the construction of a truss in which the chords and webs are of timber, it is common to use a conventional gang nail plate, a typical example of which is illustrated in Figure 1 of the drawings. The conventional gang nail plate 1 comprises a metal plate 2 configured to provide rows of sharp points 3 projecting from one side of the plate. The rows of sharp points 3 are formed by punching -8apertures into the plate 2 from the opposed side of the plate to that from which the points 3 project. In Figure 1, the punched apertures are visible. In use, the gang nail plate 1 is used to join timber truss members together, typically in edge or butt jointing configuration. The gang nail plate 1 is positioned so as to overlay the abutting sections of the timber truss members and then is pressed or hammered so that the points penetrate the two truss members, with the result that the metal plate provides a joint therebetween.

Referring now to Figures 2 to 15, the twq embodiments of the invention shown in the drawings are directed to connectors 10 for interconnecting truss members to provide a truss.

The connectors 10 comprise a connector 11 according to a first embodiment and a connector 12 according to a second embodiment. The two connectors 11, 12 are described in their use in the construction of a truss 15, as shown in Figure 4.

The truss 15 comprises an upper chord 17 and a lower chord 18 both of timber, and webs 19 of metal such as steel. The chords 17, 18 and the webs 19 cooperate to provide a triangulated assembly.

Because the truss 15 has chords 17, 18 of timber and webs 19 of metal, it is not possible to use conventional gang nail plates, a typically example of which is illustrated in Figure 1 as mentioned above.

Referring now to Figure 2 of the drawings, the connector 11 according to the first embodiment comprises a metal plate 20, having a first portion 21 and a second portion 22. The first portion 21 is provided with a plurality of projecting points 23 arranged in rows, somewhat similar to an arrangement of points on a conventional gang nail plate. The second portion 22 is without points, simply presenting a planar face.

Referring now to Figure 3 of the drawings, the connector 12 according to the second embodiment also comprises a first portion 21 incorporating points 23 and a second portion 22 without points. In this embodiment, the second portion 22 is -9divided into two sub-portions 22a and 22b, and the first portion 21 is arranged around the two sub-portions 22a and 22b.

In each embodiment, the first portion 21 incorporating the points 23 is adapted to be secured to a respective one of the timber chords 17, 18 by having the points 23 driven into the chords in a similar fashion to a conventional gang nail plate.

The second portion 22 has a further connector, or alternatively a steel web, fixed thereto, as will become apparent later.

Figure 5 illustrates a connection between the upper chord 17 and the lower chord 18, using connectors 11, 12 according to the first and second embodiments in combination. Specifically, the connector 12 according to the second embodiment is fixed to the upper chord 17 by having the points 23 thereof driven into the chord. This is preferably done prior to assembly of the truss. The connector 11 according to the first embodiment is secured to the lower chord 18 by having the points thereof driven into the lower chord, with the second portion 22 thereof projecting beyond the side of the chord so as to overlay the second portion 22 of the connector 12. Mechanical fixings 28 such as nails are then driven through the second portion 22 of the first connector 11 and into the sub-portions 22a and 22b of the second connector 12. The two chords 17, 18 are thus interconnected by the connectors 11 and 12 being mechanically fixed together. The nails 28 also of course embed into the upper chord 17.

Referring now to Figure 6 of the drawings, there is shown a connection between two webs 19 and the lower chord 18 using a connector 12 according to the second embodiment. The connector 12 according to the second embodiment is fixed to the lower chord 18 by having the points thereof driven into the chord.

This is preferably done prior to assembly of the truss. The steel webs 19 are then fixed to the connector 12, one web being mechanically fixed to sub-portion 22a thereof and the other web being mechanically fixed to sub-portion 22b thereof. The mechanical fixing is achieved by way of nails 29 driven through the steel webs 19, as well as the intervening sub-portions 22a and 22b, and into the timber chord 18. With this arrangement, the fixing provides a connection between the metal of the steel web 19 and the metal of the connector 12, as well as also being embedded in the timber of the chord 18. This provides a superior connection than merely driving mechanical fixings (eg. nails) through the steel web directly into the timber of the lower chord without the intervening metal plate of the connector therebetween, which when present assists in maintaining the integrity of the timber.

The steel webs 19 can be of any appropriate profile.

The steel webs may, for example, be of channel configuration, several typical examples of which are illustrated in Figures 7 to 10 of the drawings. In each case, the web 19 comprises two side portions 33 and an bridge portion therebetween.

At the end of the web 19 to be secured to the chord 18, a notch 37 is formed to receive the chord 18, the notch 37 being created by removing the adjacent end section of the bridge portion 35. In this way, the side 37a of the notch 37 defined by the adjacent side portions 33 can be positioned one to each side of the chord.

One of the notch sides 37a thus overlays the connector 12 in readiness to receive the mechanical fixings. In certain situations, it may desirable to provide two connectors 12 one on each side of the chord, thereby allowing both sides of the notch 37 to be fixed to the chord, strengthening the connection between the chord and the web. Such an arrangement is shown in Figure 11.

In another arrangement, the web 19 can be of tubular cross-section, typical examples of which are illustrated in Figure 12 where the web is of rectangular cross-section and Figure 13 where the web is of circular cross-section.

In such an arrangement, the web can be secured to the chord 18 in an offset relationship, as illustrated in Figure 14, where mechanical fixings 41 are inserted through the sidewall of the tubular web and into the timber chord 18, with a connector 12 therebetween.

-11 Where it is desired for the chord 18 and the web 19 to be co-planar, the side wall of the chord at the end thereof can be deformed by lateral compression to produce a tongue 43 which is fixed to the chord 18 by mechanical fixings 45 with a connector 12 in between, as shown in Figure While the embodiments have been described in which fixing of the metal webs to the metal plates 13 by way of mechanical fixing, it should be appreciated that other fixing arrangements are possible. For example, the metal components may be bonded by way of welding.

Various other connections between truss elements (chords and webs) are illustrated in Figures 16 to 20 using connectors according to embodiments of the invention. In particular figures 16 and 20 depict various configurations of timber members 17a connected together using connectors 10 whilst figures 17, 18 and 19 depict various configurations of timber members 17a and metal webs 19a connected together using connectors 10. In the configurations shown in figures 16, 17, 18 and 20 the connectors 10 vary between those having large or dense first portions 21, which incorporate the plurality of projecting points 23, and those in which the first portions 21 are not as spansive.

Construction of trusses using connectors according to the invention is particularly conducive to an automated system.

An example of an automated system appropriate for construction of trusses using connectors according to the invention is illustrated in Figures 21 and 22.

The automated system has provision for cutting timber to length in the appropriate configuration to provide timber components for a truss, and also provision for applying connectors at appropriate locations on the timber components. This will be explained in more detail later. Further, the system has provision for forming the necessary connectors for each truss component by way of an automated process, also as will be explained in more detail later.

-12- Referring now to Figure 21 of the drawings, there is illustrated schematically an automated system 50 comprising a feed path 51 along which lengths of timber are conveyed in their longitudinal direction between an in-feed table 53 and a kick-off table 55. The feed path 51 comprises a continuous conveyor belt for carrying the lengths of timber in end to end relationship without any gaps therebetween.

Between the in-feed table 53 and kick-off table 55 there is provided, in sequence, a measuring station 57, a first cutting station 59, a plating station 61 and a second cutting station 63.

The measuring station 57 comprises a measuring wheel 65 in rolling engagement with the timber being conveyed along the feed path 51 for measuring lengths thereof and providing such information as necessary to the cutting and plating stations.

The first cutting station 59 comprises a mitre saw capable of cutting the timber into prescribed lengths and also cutting notches as required within the lengths of timber. The mitre saw is capable of rotation through 900 as necessary in order to achieve required cutting profiles.

The plating station 61 includes a plating machine 67 for applying gang nail connectors to the cut timber.

The plating machine 67 is shown in more detail in Figure 22 of the drawings and comprises two plating mechanisms 68, 69 on opposed sides of the timber path 51.

Each plating mechanism 68, 69 comprises a supply of material 71 from which the connectors are formed. In the present case, the supply of material 71 comprises a coil 72 from which metal in strip form is unwound and fed to a stamping device 73 which punches apertures into the strip to form sharp points in the strip. The points are formed in the pattern and position required for the connector being -13formed. The stamping device 73 is conveniently hydraulically operated, although of course any other appropriate power source may be employed.

The stamped strip is then fed to a cutter 75 which cuts the strip as necessary to form the required connector. The connector so formed is then fed to an application location 77 at which the connector is presented to particular timber component for which it is intended with its points in contact therewith. The connector then advances (with the timber with which it is in contact) to a press 79 at which it is driven into the timber such that its points are embedded therein. In this example, the press 79 comprises a roller press, with the roller 81 thereof pressing upon the connector to drive it into engagement with the timber.

The timber advances through the plating station 61 under the driving influence of a plurality of pairs of drive wheels 83 disposed at intervals along the feeding length of the plating station. As illustrated in the drawing, the drive wheels of each pair are disposed on opposed sides of the timber.

A measuring wheel arrangement 85 measures linear movement of the timber through the plating station 61.

From the plating station 61 the timber components are advanced to the second cutting station 63 at which compound mitre cuts can be made according to specific requirements, such as hips.

From the foregoing, it is evident that the present embodiments each provide a simple yet highly effective connector which can be used for joining structural members where at least one is of timber. While the connectors according to the embodiments can be used for joining two or more timber structural members together, they are particularly convenient for joining structural members where one is of timber and the other is of metal. The ability to fix timber and metal structural members together is particularly advantageous.

It should be appreciated that the scope of the invention is not limited to the scope of the embodiments described.

-14- Modifications and improvements can be made without departing from the scope of the invention.

Obviously in constructing a truss the members of that truss may be made solely from, or a combination of metal, timber, plastic or any other suitable material.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims (27)

1. A connector for joining structural members at least one of which comprises timber, the connector comprising a metal plate having a portion thereof presenting a plurality of points projecting from one face of the plate and a further portion thereof without points to which a further structural member can be fixed.

2. The connector according to claim 1 wherein the further structural member comprises timber or metal.

3. The connector according to claim 1 or 2 wherein the further structural member is fixed to the further portion of the plate.

4. The connector according to claim 3 wherein the further structural member is mechanically fixed to the further portion of the connector, such as by nails or screws. The connector according to claim 3 wherein the further structural member comprises metal, the further structural member can be fixed to the connector by a bonding process, such as welding.

6. A truss constructed using a connector according to any one of claims 1 to

7. A truss comprising a timber chord, a metal web, and a connector for joining the web and chord, the connector comprising a metal plate having a first portion presenting a plurality of points which project from one face thereof and which are driven into the timber chord, the metal plate having a second portion without points to which the metal web is fixed.

8. The truss according to claim 7 wherein the metal web is fixed to the metal plate by being bonded thereto such as by welding. -16-

9. The truss according to claim 7 wherein the metal web is fixed to the metal plate by at least one mechanical fixing such as a nail or screw. truss according to claim 7, 8 or 9 wherein the metal web preferably has an end thereof configured for fixing to the metal plate.

11.The truss according to claim 10 wherein the metal web is of tubular construction, the end of the tubular web is deformed to provide a tab for attachment to the metal plate.

12.The truss according to claim 11 wherein the tab is aligned with the central longitudinal axis of the chord.

13.The truss according to claim 11 wherein the tab is offset laterally from the central longitudinal axis of the chord.

14.The truss according to claim 13 wherein the lateral offset is such that the tab is aligned with a longitudinal edge of the chord. truss according to any one of claims 7 to 10 wherein the web comprise a channel having two side portions and a bridge portion extending therebetween.

16.The truss according to claim 15 wherein the channel is notched at one end thereof by removal of a section of the bridge portion to provide a recess in which the chord can be accommodated, with sides of the notch in the channel located to the sides of the chord, and at least one notch side being joined to the chord through the connector.

17.An automated system for cutting members of a truss and applying one or more connectors to the members, the automated system comprising a feed path, along which lengths of timber are conveyed in their longitudinal direction, the feed path incorporating an in-feed table, a measuring -17- station, a first cutting station, a plating station, a second cutting station and a kick-off table.

18.The automated system according to claim 17 wherein the feed path comprises a continuous conveyor belt for carrying the lengths of timber in end to end relationship without any gaps therebetween.

19. The automated system according to claim 17 or 18 wherein the measuring station comprises a measuring wheel in rolling engagement with the timber being conveyed along the feed path for measuring lengths thereof and providing such information as necessary to the cutting and plating stations. automated system according to claim 17, 18 or 19 wherein the first cutting station cuts the timber into prescribed lengths in addition to cutting any required notches.

21.The automated system according any one of claims 17 to 20 wherein the plating station includes a plating machine for applying one or more nail connectors to the cut timber.

22.A plating machine for manufacturing a connector according to claim 1.

23.The plating machine according to claim 22 comprising: at least one plating mechanism which feeds a strip of material to a stamping device, the stamping device punching apertures into prescribed portions of the strip to form a plurality of sharp points protruding from one face of the strip; a cutter into which the stamped strip is fed, wherein the cutter cuts the strip as necessary to form the required connector; -18- an application location at which the connector is presented to a timber component with its points in contact therewith; and a press whereby the connector is driven into the timber such that its points are embedded therein.

24.The plating machine according to claim 23 wherein there are two plating mechanisms located on opposed sides of the timber feed path The plating machine according to claim 23 or 24 wherein the strip material is supplied from a coil from which metal is unwound.

26. The plating machine according to any one of claims 23 to 25 wherein the timber is fed through the plating station under the driving influence of drive wheels disposed at intervals along the feeding length of the plating station.

27.The plating machine according to any one of claims 23 to 26 further comprising a measuring wheel arrangement for measuring linear movement of the timber through the plating station.

28.A method of manufacturing and applying one or more connectors to a structural member comprising the steps of: passing a length of timber along a feed path to a measuring station through which a prescribed length of timber is passed to a first cutting station; cutting the timber to form the prescribed length; forming a connector with the prescribed projections, and aligning the connector adjacent the timber at the desired location; -19- passing the timber and connector through a press whereby the press causes the projections of the connector to be embedded in the timber such that the connector is secured to the timber.

29.A connector as substantially herein described with reference to figures 2 to 22. truss as substantially herein described with reference to figures 2 to 22.

31.A plating machine as substantially herein described with reference to figure 22.

32.An automated system as substantially herein described with reference to figure 21.

33.A method of manufacturing and applying one or more connectors as substantially herein described. Dated this Twenty Fifth day of January 2006. Formsteel Pty Ltd Applicant Wray Associates Perth, Western Australia Patent Attorneys for the Applicant