AU2022279450A1 - A timber connector and related methods - Google Patents

Abstract

A connector comprising a connector body including a first region and a second region which are joined by a resilient transition region. The second region of the body extends laterally of the first region, in a first lateral direction, such that the second region and the first region together bound an angle. Flexing of the resilient transition region permits rotation of the second region relative the first, in order to increase the size of the angle. The connector body further comprises at least one penetrator. The at least one penetrator is adapted to penetrate a timber joist. The at least one penetrator extends from, and laterally of, said first region in a second lateral direction which substantially opposes the first lateral direction.

Description

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A TIMBER CONNECTOR AND RELATED METHODS

The present invention relates to apparatus and methods for joining timber, such as elongate timber joists.

Background

During the construction of timber structures it is often necessary to connect elongate joists, often extending orthogonally relative to one another, but sometimes in different configurations. Typically metallic joiners are affixed to the joists in order to secure the joints between them, and resist loads applied to the structure. Typically several metallic joiners are needed at each joint to connect the joists, and to ensure that the joint can withstand loads acting in different directions. It can be inconvenient and time-consuming to place and affix all of the metallic joiners required to construct the joint, and the multiple joiners required for each joint can add to the cost of construction. If the joiners are not positioned accurately and secured tightly then there may be a degree of slack in the joint, and this can enable the joists to move relative to one another and weaken the joint and/or structure. It is therefore an object of the present invention to provide a connector and/or a method of connection which at least partially ameliorates at least some of the abovementioned disadvantages or which at least provides the public with a useful choice.

Summary of Invention

In a first aspect the present invention may be said to be a method of forming a butt joint of a first joists to a second joist using a connector that comprises a connector body formed from a single piece of plate material that includes a first region and a second region joined by a resilient transition region, wherein said second region of the body extends laterally of the first region in a first lateral direction such that the second region and the first region together bound a acute angle, and wherein flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle from the relaxed acute angle, and wherein said connector body further comprises at least one penetrator formed from the single piece of plate material and adapted to penetrate a timber joist, extending from, and laterally of, said first region in a second lateral direction which substantially opposes the first lateral direction, said method comprising the steps of:

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positioning the second region against a longitudinal face of a first joist to which the second joist is to butt prior to, during or after the connector is penetratingly fixed to the second joist by the at least one penetrator, achieving said fixing as aforesaid and subsequently to said positioning step, driving at least one fastener through the second region into a longitudinal face of the first joist, against which the connector attached second joist butts, the driving leaving the plate material in flex from its relaxed acute angle. Also herein described is a connector, comprising a connector body including a first region and a second region joined by a resilient transition region, wherein said second region of the body extends laterally of the first region, in a first lateral direction, such that the second region and the first region together bound an acute angle, and wherein flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle, and wherein said connector body further comprises at least one penetrator adapted to penetrate a timber joist, extending from, and laterally of, said first region in a second lateral direction which substantially opposes the first lateral direction. In some embodiments the connector is that for a joint of timber joists. In some embodiments the size of the acute angle is between 80 degrees and approaching 90 degrees (for example 83 degrees, 85 degrees or 88 degrees). In some embodiments flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle to a size approaching 90 degrees, and in some embodiments beyond 90 degrees (for example up to 95 degrees, up to 100 degrees, up to 105 degrees, up to 110 degrees, up to 120 degrees or up to 140 degrees). In some embodiments said transition region defines a bend. In some embodiments wherein at least one of the first region and second region are of planar form. In some embodiments said first region and/or said second region are of plate form. In some embodiments the connector body is formed from a single piece of plate material. In some embodiments wherein said at least one penetrator has been punched or folded from the material of the first region of the body. In some embodiments said at least one penetrator is located distal from the transition region. In some embodiments said at least one penetrator is located along a perimeter edge of the first region of the body, being the edge which is distal-most from the transition region.

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In some embodiments there are at least two penetrators extending from, and laterally of, said first region. In some embodiments said penetrators are located at opposing edges of the first region. Also herein described is a connector, comprising a connector body including a first region and a second region joined by a resilient transition region, wherein said second region of the body extends laterally of the first region, in a first lateral direction, such that the second region and the first region together bound an angle, and wherein flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle, and wherein said connector body further comprises at least one penetrator adapted to penetrate a timber joist, extending from, and laterally of, said first region in a second lateral direction which substantially opposes the first lateral direction. In some embodiments the connector is a connector for a joint of timber joists disposed at an angle relative to one another. In some embodiments the angle bounded by the first and second regions of the connector is less than the angle between the joists to be joined. In some embodiments the flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle. In some embodiments prior to flexing the angle is an acute angle. In some embodiments the angle bounded by the first and second regions of the connector is up to 15 degrees less than the angle between the joists to be joined. In some embodiments the angle bounded by the first and second regions of the connector is 5 or 10 degrees less than the angle between the joists to be joined. In some embodiments said first region and/or said second region are of planar form. In some embodiments said first region and/or said second region are of plate form. In some embodiments the connector body is formed from a single piece of plate material. In some embodiments said penetrator has been punched or folded from the material of the first region of the body. In some embodiments said at least one penetrator is located distal from the transition region. In some embodiments said at least one penetrator is located along a perimeter edge of the first region of the body, being the edge which is distal-most from the transition region.

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In some embodiments there are at least two penetrators extending from, and laterally of, said first region. In some embodiments said penetrators are located at opposing edges of the first region. Also herein described is a connector formed from a resilient plate material to define two substantially planar regions connecting through a bend axis of the plate material, the bend being obtuse/acute thereby to define an 'obtuse' face and an 'acute' face of each substantially planar region; wherein at least one of said substantially planar regions has at least one integral timber penetrator drivable in its region's acute face to obtuse face direction. In some embodiments the connector is that for a joint of timber joists. In some embodiments the size of the acute angle is between 80 degrees and approaching 90 degrees (for example 83 degrees, 85 degrees or 88 degrees). In some embodiments under flexing the size of the angle increases so it approaches or reaches 90 degrees. In some embodiments under flexing the size of the angle increases so it approaches or reaches 95 degrees. In some embodiments prior to flexing the angle is not an acute angle, and wherein the size of the angle increases up to 95 degrees. In some embodiments prior to flexing the angle is not an acute angle, and wherein the size of the angle increases up to an angle between 95 degrees and 140 degrees. In some embodiments under flexing the size of the angle increases by an amount less than 10 degrees. In some embodiments under flexing the size of the angle increases by an amount less than 15 degrees. In some embodiments said penetrator has been punched or folded from the material of the planar region. In some embodiments said at least one penetrator is located distal from the bend. In some embodiments said at least one penetrator is located along a perimeter edge of the one or other of the planar regions, being the edge which is distal-most from the bend. In some embodiments the planar region has at least two integral timber penetrators. In some embodiments said penetrators are located at opposing edges of the planar region.

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Also herein described is a butt joint of joists wherein a plate connector has integral penetrators penetrating a longitudinal face of one joist from one plate region of the connector, and has at least one integral and/or non-integral penetrator penetrating an orthogonal longitudinal face of the second joist to hold a second plate region thereto in a state of flex from an obtuse/acute relaxed transition from the first plate region into the second plate region. In some embodiments the connector is a connector as previously described. Also herein described is a butt joint of joists wherein a plate connector has integral penetrators penetrating a longitudinal face of one joist from one plate region of the connector, and has at least one integral and/or non-integral penetrator penetrating an adjacent longitudinal face of the second joist to hold a second plate region thereto in a state of flex from an obtuse/acute relaxed transition from the first plate region into the second plate region. Also herein described is a connector formed from a resilient plate material to hold in juxtaposition two joist members to form or forming a butt joint, the connector comprising a first plate region to lie against a longitudinal face of a first of said joist members, a second plate region extending from the first plate region at an angle by a bend from the first plate region, and at least one plate penetrator bent from at least one perimeter of, or punched from part of, the first plate region; the connector allowing the opposing obtuse side of the acute bend to be positioned against, or adjacent, the second of said joist members, the at least one penetrator of the first plate region then to be forced into the first of the joist members, and then the second plate member to be fixed to said second of the joist members to lie against, or closely adjacent, a longitudinal face of the second of the joist members. In some embodiments the two joist members to be held in juxtaposition are disposed at an angle relative to each other, the angle between the joists being greater than the acute angle of the bend of the plate material. In some embodiments an engagement of the at least one penetrator of the first plate region and a fixing of the second plate member to their respective joist members leaves the plate material in flex away such that the acute angle of the bend is increased. In some embodiments the connector is a connector as previously described. Also herein described is a joint of a timber structure comprising a first elongate joist and a second elongate joist aligned so as to extend in orthogonal directions relative to one another, and further comprising a resilient connector affixed to and connecting perpendicular longitudinal faces of the first and second joists,

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wherein said connector is affixed in a state of flex to exert a force on the second joist, said force acting to resist movement of the second joist relative the first joist in a first direction parallel to the elongate axis of the first joist, and wherein said connector further resists relative movement of the joists in a direction perpendicular to said first direction. In some embodiments the resilient connector comprises the connector as previously described. In some embodiments the connector has a body formed entirely from a single piece of plate material. In some embodiments the connector is a connector as described above. In some embodiments said joint is a perpendicular butt joint of said first and second joists. In some embodiments the joint is configured such that at least two longitudinal faces of said first and second joists are co-planar. In some embodiments the joint further comprises a second resilient connector affixed to an opposed longitudinal face of the first joist from that to which the first resilient connector is affixed. In a further aspect the invention can be said to broadly consist in a butt joint of a timber structure comprising a first elongate joist connected at an end region to a second elongate joist, and further comprising a resilient connector affixed to and connecting adjacent longitudinal faces of the first and second joists, said faces defining an angle between them, said connector having first and second plate regions joined through a resilient bend of a plate material, wherein the connector has at least one integral penetrators penetrating a longitudinal face of one joist from one plate region of the connector, and has at least one fastener penetrating an adjacent longitudinal face of the second joist to hold a second plate region thereto such that the resilient bend is assumed into a state of flex from a relaxed condition, and wherein, in the relaxed condition, the angle defined by the bend is less than the angle between the adjacent longitudinal faces of the first and second joists. In some embodiments the angle defined by the bend in its relaxed condition is up to 15 degrees less than the angle between the adjacent longitudinal faces of the first and second joists. In some embodiments the angle defined by the bend in its relaxed condition is between 5 and 10 degrees less than the angle between the adjacent longitudinal faces of the first and second joists. In some embodiments the connector is a connector as described above.

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In some embodiments a connector substantially as described herein with reference to any one or more of the figures. In some embodiments the joint is configured such that at least two longitudinal faces of said first and second joists are co-planar. Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings. As used herein the term "and/or" means "and" or "or", or both. As used herein "(s)" following a noun means the plural and/or singular forms of the noun. As used herein the term "joist" refers generally to elongate members used in timber construction, and includes beams, nogging, purlins, studs, braces and other like members. As used herein the term "comprising" means "consisting at least in part of". When interpreting statements in this specification which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present. Related terms such as "comprise" and "comprised" are to be interpreted in the same manner. This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.)

Description of Drawings

The invention will now be described by way of example only and with reference to the drawings in which: Figure 1 shows a typical arrangement for the construction of a timber structure wherein a series of elongate joists are connected to one another so as to extend in orthogonal directions relative to one another; Figure 2 shows a side on cross-sectional view detailing a butt joint of the arrangement shown in Figure 1; Figure 3 shows a front isometric view of a connector; Figure 4 shows a rear isometric view of the connector of Figure 3; Figure 5 shows a top view of the connector of Figure 3; Figure 6 shows an alternative embodiment of a connector;

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Figure 7 shows the connector of Figures 3 to 5 in use, with a first region of the connector having been affixed to a longitudinal face of a first joist of the butt joint; Figure 8 shows the connector of Figure 7, with a second region of the connector having been affixed to a longitudinal face of the second joist of the butt joint; and Figure 9 shows the connector of the previous Figures being used to connect joists in an alternative orthogonally extending arrangement.

Detailed Description of the Invention

Figure 1 shows a typical arrangement for the construction of a timber structure, wherein a series of elongate joists are connected to one another so as to extend in orthogonal directions relative to one another. Typically the joists are of rectangular cross section, each having four longitudinal faces. At certain points of the structure, an end region of a first joist 200 will be connected at a longitudinal face 301 of a second joist 300, so as to form a perpendicular butt joint 100 with the second joist 300 extending in a direction perpendicular to the elongate direction 102 of the first joist 200. The butt joint 100 needs to resist relative movement of the first and second joists 200,300 in the shear direction 101, shown in Figure 2. The butt joint 100 also needs to resist relative movement of the first and second joists 200,300 in the elongate direction 102 of the first joist 200 shown in Figure 1. Typically support in the shear direction 101 is provided by metallic joiners 103, such as those shown in Figures 1 and 2, which take the form of a metallic plate with a perpendicular bend. The plate is fixed to the adjacent longitudinal faces 201, 301 by fasteners which extend into the first and second joists 200,300. Typically support in the elongate direction 102 of the first joist 200 is provided by metallic strips 104 which extend between co-planar longitudinal faces 202,302 of the first and second joists 200,300 as shown in Figure 1. In some embodiments, an advantage of the present invention may be in providing for the joint 100 to be secured in both the shear direction 101 and the elongate direction 102 of the first joist 200 by a single connector 400 component. The manner in which this is achieved is described below. In some embodiments there is a connector with a connector body 401, with a first region 500 (which is in use to affix to a longitudinal face 201 of the first joist 200), and a second region 700 projecting transversely of the first region 500. The connector 400 may be formed, at least in part, from a resilient plate material, such that there is a bend at a transition region 600 of the plate between the first and second regions 500,700. There may be an acute angle 601, marked in Figures 3 and 5, between the first and second regions 500,700 about the bend axis 603. Accordingly there may be a

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corresponding obtuse angle 602, as marked in Figures 3 and 4, between the first and second regions 500,700 about the bend axis 603. In some embodiments the size of the acute angle is between 80 degrees and approaching 90 degrees (for example 83 degrees, degrees or 88 degrees). As shown in Figure 5, the connector 400 may have an acute face 501 of the first region 500 and an acute face 701 of the second region 700 which bound the acute angle 601. The connector 400 may also have an obtuse face 502 of the first region 500 and an obtuse face 702 of the second region 700 which bound the obtuse angle 602. Figures 3 to 5 show the connector body 401 with the resilient transition region in a relaxed condition. However the resilient transition region 600 may be able to flex, permitting the second region 700 to rotate about the bend axis 603 so as to increase the size of the acute angle 601. The transition region 600 may flex enough to permit the acute angle 601 to approach 90° without causing any non-resilient deformation of the connector body 401. In some embodiments the transition region may flex enough to permit angle 601 to become obtuse without causing any non-resilient deformation of the connector body 401. For example angle 601 may be able to increase up to 95 degrees, up to 100 degrees, up to 105 degrees, up to 110 degrees, up to 120 degrees or up to 140 degrees when the connector body 401 is brought into a state of flex. The connector 400 may have one or more penetrators 503 to penetrate into the joist and assist with affixing the connector 400. As can be seen in Figure 5, the second region 700 of the body 401 projects laterally of the first region 500. The penetrators 503 may project out from the body 401 in the laterally opposite direction. Preferably there are at least two penetrators 503 to provide the required resistance to loading of the joint 100. The penetrators 503 may be adapted to be driven into the longitudinal face of the first joist 200 in a direction perpendicular to the elongate direction 102 so as to resist movement of the connector in that direction 102. For example, penetrators 503 may project from the obtuse face 502 of the first region 500 as shown in Figures 3 to 5. The penetrators 503 may have, at least in part, a pointed or wedge-shaped profile, as seen in Figures 3 to 5, to aid penetration. The penetrators 503 may be located at the first region 500 some distance distal from the transition region 600. As an example the penetrators 503 may be located at opposed edges of the first region 500, seen in Figures 3 and 4. As a further example the penetrators 503 may be located on an edge of the first region 500 distal most from the transition region 600, seen in Figure 6. In some embodiments the first and second regions 500,700, and penetrators 503, may all be cut from a single piece of plate material and folded into place. Optionally the penetrators 503 could be punched from the plate. This allows for a simplified manufacturing procedure.

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In some embodiments the connector 400 may have plate-form first and second regions 500,700 to lie substantially flush with the longitudinal faces that they are joining. However it will be appreciated that differing forms could be used without substantially affecting the function of the connector 400, for example there could be additional flanges or stiffening ribs projecting from the first and/or second regions 500,700. Below is set out a sequence for joining joists using the connector 400 described above. This is described with reference to Figures 7 and 8. The first and second joists 200, 300 may be bought into a butt joint 100 configuration. The first region 500 of the connector 400 may be positioned on a longitudinal face 201 of the first joist 200. The connector 400 may be positioned with the bend axis 603 of the transition region 600 close to the junction between the adjoining longitudinal faces 201,301 of the first and second joists 200,300. The penetrators 503 may serve to lightly tack the connector 400 into position. When the desired positioning has been achieved, the penetrators 503 can be driven into the joist to affix the first region 500 to the longitudinal face 201. The first region 500 may also have apertures for inserting fasteners 703. The fasteners 703 (for example screws or nails) can extend into the joist in order to hold the first region 500 to the longitudinal face 201, thus preventing the first region 500 of the connector 400 from being able to be pulled away from the joist. The second region 700 can then be affixed to an adjacent longitudinal face 301 of the second joist 300. For example, the second region 700 may have apertures for inserting fasteners 703 (for example screws and nails) that can extend into the second joist 300. As the fasteners 703 are inserted, they press on the second region 700 of the connector 400 and the transition region 600 of the connector 400 flexes to permit the second region 700 of the connector 400 to be drawn towards the longitudinal face of the second joist 300. As an alternative, in some embodiments it may be possible to first affix the second region 700 to the second joist 301, and then subsequently hammer or press the penetrators 503 of the first region 500 into the face 201 of the first joist affix the first region 500. In either case, the acute bend of the transition region 600 makes it possible to fit the body 401 of the connector snugly into the 90 degree junction between the joists before the connector 400 is fixed into place. The acute angle 601 increases as the connector is fixed into place, and thus the connector 400 is affixed in a state of flex. Because the connector 400 is affixed in a state of flex, the connector body 401 takes up any slack or play that might otherwise be afforded. And thus a tidy and secure connection may be achieved.

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Shown in Figure 8, as the increase in angle 601 is against the bias of the resilient transition region 600, the connector exerts a force on the second joist 300 which pulls the second joist 300 back towards the end of the first joist 200 in the elongate direction 102. The connector is preferably affixed in a state of flex, such that the angle 601 between the first and second regions is around 90 degrees (for example, the angle may be between 90 and 95 degrees). With the first and second regions 500,700 of the connector 400 affixed to the adjacent longitudinal faces 201,301 of the joists (the condition shown in Figure 8) the butt joint 100 is supported to resist movement in both the shear direction 101 and the elongate direction 102 of the first joist 200. In some embodiments a corresponding connector 400 may be applied to the opposing longitudinal face 203 of the first joist 200 (marked on Figure 8) to evenly apply force to the second joist on either side of the butt joint 100. Although in the sequence above it has been described that the joists should be positioned prior to affixing the connector 400, it would also be possible to affix at least one region (500 or 700) of the connector 400 to a longitudinal face of one of the joists as a step prior to positioning of the joists. For example this could be done before the joists are brought to site. With reference to the exemplary embodiment shown in Figures 7 and 8, it would be possible to supply the first joist 300 with the first region 500 of the connector affixed to a longitudinal face 201 (and optionally a second connector affixed to an opposing longitudinal face 203). The joists 200,300 could then be assembled into their orthogonal configuration on site, and the second region(s) 700 of the connector(s) 400 could be affixed to secure the joint 100. While previous examples of the present invention are described in relation to the securing of butt joints, it will be appreciated that the invention could similarly be applied to other types of joints where there is a requirement for first and second joists 200,300 to be connected to one another so as to extend an orthogonal directions relative to one another. An example of such an alternative configuration of the joists is shown in Figure 9. It will be appreciated that in this configuration the connector 400 serves to resist against relative movement of the joists in the direction of the arrows shown as 101 and 102. While previous examples of the present invention are described in relation to the securing of perpendicular butt joints, it will be appreciated that the invention could similarly be applied to other types of butt joints (for example oblique butt joints) where the joists are joined at angles at other than 90 degrees. In these embodiments the bend through the transition region 600 may be less (for example 5 or 10 degrees less, or up to degrees less) than the angle between the two longitudinal faces of the joists to which the connector 400 is to be affixed so that the connector assumes a state of flex when

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affixed. For example, where the connector 400 is to be affixed to joists butt jointed at a 135 degree angle, then the size of the angle 601 bounded by the first 500 and second 700 plate regions may be less than 135 degrees (for example 125 or 130 degrees) when the connector is in its relaxed state with no flexing of the resilient transition region 600. Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth. Although the invention has been described by way of example and with reference to particular embodiments, it is to be understood that modifications and/or improvements may be made without departing from the scope or spirit of the invention.

Claims (10)

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1. A connector formed from a resilient plate material to hold in juxtaposition two joist members to form or forming a butt joint, the connector comprising a first plate region to lie against a longitudinal face of a first of said joist members, a second plate region extending from the first plate region at an angle by a bend from the first plate region, and at least one plate penetrator bent from at least one perimeter of, or punched from part of, the first plate region; the connector allowing the opposing obtuse side of the acute bend to be positioned against, or adjacent, the second of said joist members, the at least one penetrator of the first plate region then to be forced into the first of the joist members, and then the second plate member to be fixed to said second of the joist members to lie against, or closely adjacent, a longitudinal face of the second of the joist members, wherein the two joist members held in juxtaposition are disposed at an angle relative to each other, the angle between the joists being greater than the acute angle of the bend of the plate material and wherein an engagement of the at least one penetrator of the first plate region and a fixing of the second plate member to their respective joist members leaves the plate material in flex away such that the acute angle of the bend is increased.

2. A method of forming a butt joint of a first joists to a second joist using a connector that comprises a connector body formed from a single piece of plate material that includes a first region and a second region joined by a resilient transition region, wherein said second region of the body extends laterally of the first region in a first lateral direction such that the second region and the first region together bound a acute angle, and wherein flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle from the relaxed acute angle, and wherein said connector body further comprises at least one penetrator formed from the single piece of plate material and adapted to penetrate a timber joist, extending from, and laterally of, said first region in a second lateral direction which substantially opposes the first lateral direction, said method comprising the steps of: positioning the second region against a longitudinal face of a first joist to which the second joist is to butt prior to, during or after the connector is penetratingly fixed to the second joist by the at least one penetrator, achieving said fixing as aforesaid and subsequently to said positioning step, driving at least one fastener through the second region into a longitudinal face of the first

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joist, against which the connector attached second joist butts, the driving leaving the plate material in flex from its relaxed acute angle.

3. The method as claimed in claim 2, wherein the angle bounded by the first and second regions of the connector is less than the angle between the joists to be joined.

4. The method as claimed in anyone of claims 2 or 3 wherein flexing of the resilient transition region permits rotation of the second region relative the first in order to increase the size of the angle.

5. The method as claimed in anyone of claims 2 to 4 wherein the size of the acute angle is between 80 degrees and approaching but not 90 degrees.

6. The method as claimed in anyone of claims 2 to 5 wherein under flexing the size of the angle increases so it approaches or reaches 90 degrees.

7. The method as claimed in anyone of claims 2 wherein both the first region and second region are of planar form.

8. The method as claimed in anyone of claims 2 to 7 wherein said at least one penetrator has been punched or folded from the material of the first region of the body.

9. The method as claimed in claims 2 to 8 wherein said at least one penetrator is located distal from the transition region.

10. The method as claimed in claim 9 wherein said at least one penetrator is located along a perimeter edge of the first region of the body, being the edge which is distal-most from the transition region.